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This application is a division of application Ser. No. 07/452,896, filed Dec. 19, 1989, now abandoned.
FIELD OF THE INVENTION
This invention relates to solid film-forming compositions for use in coating foods and pharmaceuticals and the like. More particularly, the invention is concerned with such film-forming compositions which are dispersible in aqueous media.
BACKGROUND OF THE INVENTION
It is well known in the art to envelop solid pharmaceutical materials, tablets, granules and seeds, for example, in a film covering as protection against oxidation, moisture, light, abrasion, rough handling, etc. The film should be free of roughness, irregularities, cracks or mottled colorations. Film smoothness is important as an aid in swallowing. A hard, shiny surface is desirable for an attractive appearance. Of course, films and coating compositions for ingestion must be edible or physiologically compatible.
Film-forming compositions for coating pharmaceutical tablets preferably contain as the film-forming element, a film-forming resinous material, either naturally occurring or synthetic. Normally, such compositions are applied as a liquid coating formulation comprising a liquid carrier medium having dispersed or dissolved therein the film-forming components. The liquid medium can be an organic solvent or water or a combination of both. Water is preferred owing to the risk of fire and toxicity from organic solvents. Also having to comply with governmental safety standards pertaining to the transportation and handling of industrial chemicals is another minus factor against solvent use.
Generally speaking, application of the liquid coating formulation is effected by spraying dry pharmaceutical forms in rotation in a coating pan or in a fluidized air bed. After evaporation of the liquid medium, the film coated pharmaceuticals are recovered.
As a commercial product, liquid coating compositions are unsatisfactory because of the high transportation costs due to the weight of the liquid carrier. Clearly, it is more practical and economical to ship coating compositions in dry form which can be reconstituted with the appropriate solvent or liquid by the pharmaceutical customer. For this, a readily dispersible product is desirable which can be reconstituted by simple mixing or stirring.
It is known in the prior art to prepare dry coating formulations by grinding a polymer powder with pigment particles and grinding the mixture further to give a fine powder. However, when this is stirred into water, the polymer tends to agglomerate resulting in a nonuniform dispersion which, unless permitted to solvate for an extended period of time, gives poor coatings due to the presence of lumps and fish eyes.
An improved coating system is described in U.S. Pat. Nos. 4,543,370 and 4,683,256 assigned to the Colorcon Corporation. According to these documents, a pharmaceutical coating composition is produced by high intensity blending of polymer and pigment particles in the presence of a plasticizer. The resulting powder is mixed with water to form a coating dispersion which is applied to tablets. On drying, a uniform film is said to be produced on the tablets. The coating can also be applied as a solution in an organic solvent.
The dry coating compositions of the Colorcon patents consist of separate individual particles of pigment and polymer. Although the vigorous dry blending produces a fine powder, its heterogeneous nature is readily discernible under the scanning electron microscope.
SUMMARY OF THE INVENTION
A technique has now been found whereby solid, water dispersible film-forming compositions which are of a homogeneous nature can be realized and the provision and preparation of said compositions together with film coated pharmaceuticals and the like prepared therewith constitutes the object and purpose of the invention.
The solid water dispersible film-forming compositions of the invention comprise freeze-dried particles of a water-soluble, film-forming polymer produced by freeze-drying an aqueous solution of the polymer. Normally, the polymer solution will contain a plasticizer and pigment which subsequently appear homogeneously distributed in each of the freeze-dried particles derived from the polymer solution. On mixing the homogeneous film-forming composition with water, there is produced an aqueous film-forming coating dispersion comprising a solution of the water-soluble polymer in which are suspended any particulates such as pigments, colorants or the like. As understood herein, the term "dispersion" includes the aqueous polymer solution alone or in combination with suspended matter. The aqueous coating dispersion can be applied to various articles such as a pharmaceutical or food substrate. After drying, there remains a smooth homogeneous film envelope on the so-coated object.
DETAILED DESCRIPTION OF THE INVENTION
In carrying out the invention, there is first prepared an aqueous solution of water-soluble polymer, to which is added plasticizer and optionally a pigment. After thoroughly blending the ingredients a homogeneous liquid is produced. This generally contains a solids content of from about 5% to about 40%, preferably about 10% to about 20%. Of the solids, about 50% to about 90%, preferably about 80% to about 90% is polymer; about 2% to about 40%, preferably about 5% to about 10% is plasticizer and about 0% to about 20%, preferably about 5% to about 7.5% is pigment; all percentages are on a 100% by weight basis.
The so prepared polymer solution is subjected to freeze-drying. In the procedure employed herein, the polymer solution is frozen in bulk by placing it in large trays followed by crushing or pulverizing of the resultant frozen mass to the desired particle size. The frozen particles are then dried under vacuum with controlled heat to remove moisture and thereby produce dried polymer particles. Freeze-drying is a well known industrial technique for removing water and moisture from an aqueous substrate; see Chemical and Process Technology Encyclopedia by Douglas M. Considine, Editor-in-Chief; McGraw-Hill Book Company, pages 523-527.
The freeze-dried (lyophilized) pulverulent film-forming composition of the invention consists mainly of highly porous, sponge-like particles having a bulk density of the order of about 100 mg/ml to 400 mg/ml. However, particle size is not critical except insofar as it affects the rate of dispersion, larger particles requiring a longer time to undergo dispersion than smaller particles.
The lyophilized powder in the above produced particle sizes is dispersed in water, using ordinary mixing or agitation means, such as a variable speed propeller mixer, to give an aqueous, film-forming coating composition. Mixing time to obtain a homogeneous dispersion is of the order of about 15 to about 30 minutes. Exemplary particle size ranges from about 75 to 850 microns, preferably, about 60 to 50 microns.
Viscosity of the dispersion is a function of polymer type, concentration and molecular weight. By varying these parameters, dispersions having a wide range of viscosities can be realized. Viscosities (Brookfield RVT, Spindle #3 at 20 rpm) of the film-forming dispersions of the invention are typically in the neighborhood of 300 to 700 cps. The compositions are stable and do not settle out or agglomerate over a 24 hour period.
Microscopic examination of the freeze-dried particles reveals their homogeneous nature; none of the individual components making up the particle can be discerned. It is believed that this homogeneity at the particle level accounts for superior suspension stability of the dispersion and improved smoothness of the film coatings as compared with film coatings made from dry blends of polymer and pigment.
So far as can be ascertained, any number of water-soluble polymers are suitable in practicing the invention. Such polymers should, of course, be capable of providing films of sufficient durability and stability. Film flexibility can usually be controlled by incorporating a plasticizer in the polymer. The suitability of a particular polymer is easily established by casting and examining test films for their coating properties.
Water-soluble, film-forming polymers generally meeting the aforedelineated criteria include the known types exemplary members of which are hydroxypropyl methylcellulose, hydroxypropyl cellulose, polyvinylpyrrolidone, sodium carboxymethylcellulose, hydroxyethylcellulose, methylcellulose, and sodium ethylcellulose sulfate and mixtures thereof.
An especially suitable and most preferred water-soluble polymer is water-soluble cellulose acetate produced by the partial hydrolysis of cellulose acetate. It is a known material which is extensively documented in the patent and technical literature; see for instance, U.S. Pat. No. 3,482,011 to Bohrer and assigned to Celanese Corporation. The polymer is available in various viscosity grades from the Hoechst-Celanese Corporation, Charlotte, N.C. 28232. Films obtained with water-soluble cellulose acetate are clear, flexible, strong and durable. Tests on pharmaceutical forms coated with the pigmented polymer showed excellent preservation of cores against heat and humidity.
Water-soluble cellulose acetate employed herein is preferably a mixture of low and medium viscosity types to provide a polymer blend from which aqueous polymer dispersion can be prepared having the aforementioned viscosity in the 300 to 700 cps. range.
Any of the pigments commonly used in making coating dispersions for coating tablets and the like are suitable for inclusion in the dry film-forming compositions of the invention. Examples are FD&C and D&C lakes, titanium dioxide, magnesium carbonate, talc, pyrogenic silica, iron oxides, channel black and insoluble dyes. Also satisfactory are natural pigments such as riboflavin, carmine 40, curcumin and annatto; pigments are optional ingredients which can be omitted.
Plasticizers for the water-soluble polymer in the coatings of the invention include polyethylene glycols (PEG) having a molecular weight range of about 200 to about 4000, acetylated monoglyceride, glycerin, propylene glycol, triethyl citrate, acetyl triethyl citrate, triacetin; preferred plasticizers are glycerin and PEG 400.
The film-forming composition can be used to coat pharmaceuticals such as tablets, seeds, granules, pellets, soft and hard gelatin capsules and the like.
The aforementioned pharmaceutical dosage forms comprise drug classes such as multivitamins, multivitamins with minerals, prenatal vitamins, vitamins A and D, B 1 , B 2 , B 6 , B 12 , and vitamin B complex with vitamin C. Additional drug classes include:
Analgesics--acetaminophen, aspirin, ibuprofen, ketoprofen and the like, indomethacin, naproxen, acetaminophen with codeine and acetaminophen with propoxyphene napsylate.
Antibiotics--erythromycin, cephalosporins, etc.
Antiepileptics--phensuximide, phenytoin sodium and valproate sodium.
Antihistamines--chloropheniramine maleate, diphenhydramine hydrochloride, triprolidine hydrochloride, etc.
Cough and Cold Drugs--dextromethorphan hydrobromide, ephedrine sulfate, quaifenesin, phenylpropanolamine hydrochloride, promethazine hydrochloride, and pseudoephedrine hydrochloride.
Cardiovascular Drugs--captopril, chlorthiazide and hydrochlorthiazide, diltiazem, nadolol, papaverine hydrochloride, procainamide hydrochloride, propranolol hydrochloride, quinidine gluconate, quinidine sulfate, etc.
Electrolytes--potassium chloride.
Gastrointestnal Drugs--cimetidine, loperamide hydrochloride and ranitidine.
Respiratory Drugs--albuterol sulfate, aminophylline, theophylline, etc.
The following nonlimiting examples in which all parts are by weight unless otherwise stated, illustrate the invention.
EXAMPLE 1
______________________________________DRY FILM-FORMING COATING POWDER(A) Formula CompositionComponents Suspension Solids %______________________________________WSCA*, low viscosity (15%) 2963.0 444.5 59.3WSCA, medium viscosity (10%) 2222.3 222.2 29.6PEG 400 33.3 33.3 4.4Sepisperse ®, AP3027** 190.2 50.0 6.7Water 591.2 -- -- 6000.0 g 750.0 g 100.0______________________________________ *Water-soluble cellulose acetate **Sepisperse ® AP3027 is a commercial aqueous pigment dispersion manufactured by Seppic, Paris, France. It contains 26.3% by weight pigmen solids and 7.5% pigment solids were used based on total polymer solids.
(B) Preparation
1. Low viscosity LV (15% by weight) and medium viscosity MV (10% by weight) water-soluble cellulose acetate (WSCA) solutions are prepared separately. 2. The solutions are mixed (standard variable speed propellor-type mixer) for 60 to 120 minutes, covered and allowed to stand overnight to ensure complete hydration of the polymer. 3. Appropriate amounts of each polymer solution are combined and mixed to achieve the desired polymer ratio. In the case of this example, the polymer ratio of LV:MV is 2:1. 4. With continued mixing, water-soluble PEG 400 is added to the LV:MV WSCA polymer solution. 5. With continued mixing, Sepisperse® aqueous pigment dispersion is added to the plasticized polymer solution. 6. Water is added to the suspension to adjust the solids in the final composition to 12.5% by weight and the composition is mixed thoroughly. 7. The composition is then lyophilized by conventional freeze drying process.
(C) Film-Forming Coating Dispersion
The above obtained freeze-dried product (in powder form) can easily be redispersed in water to form a composition suitable for coating tablets and the like.
Procedure for dispersing (mixing) the freeze-dried powder is as follows:
1. With a variable speed propellor-type mixer, freeze-dried powder is added to water and mixed for 15 to 30 minutes to form a uniform dispersion.
2. In the case of this example, the concentration of solids in the coating dispersion is 12.5% by weight.
3. Following conventional tablet coating procedures as described below, the dispersion from step 2. is applied to standard acetylsalicylic acid (ASA) tablets at a film loading of 3% based on the coated tablet weight.
______________________________________Spray Coating Equipment______________________________________Pan 24" Accela-CotaBaffles 4 straight & 4 mixingPump Masterflex 7562-10Pump heads Two 7015Spray guns Two SS 7310-1/4 JAUFluid caps 1.0 mmAir caps 134255-45° SS______________________________________Spray Coating Conditions Range______________________________________Batch size (kg) 10Spray rate (ml/min/gun) 15-16Atomizing air (Bar) 1.5Gun distance (inches) 6 at 45°Air temperature (°C.)Inlet 60-75Exhaust 36-40Bed temperature (°C.) 32-35Pan rotation (rpm) 10Tablet bed warming (min. 10jogging)Total coating time (min.) 65-80Post dryingInlet air temperature (°C.) 60Drying time (min.) 20Tablet weight gain (wt/wt %) 2.7-3.0______________________________________
EXAMPLE 2
The procedure of Example 1 was repeated except that glycerin was used as the plasticizer. Comparable results were obtained.
EXAMPLE 3
The procedure of Example 1 was repeated except that hydroxypropylmethylcellulose (HPMC E-5) was substituted for the water-soluble cellulose acetate. The formulation was made up as follows:
______________________________________ g Solids %______________________________________HPMC E-5 (15%)* 5185.3 777.79 88.89PEG 400 38.9 38.85 4.44Sepisperse ® AP3027 224.5 58.36 6.67Water 1551.3 -- -- 7000.0 875.0 100.0______________________________________ *Viscosity 4 to 6 cps of a 2% solution in water. | A water dispersible film-forming particulate composition for use in coating pharmaceuticals and foods or the like, produced by freeze-drying an aqueous solution of a water-soluble polymer, a plasticizer, and optionally a pigment, is described. The product mixes readily with water to form an aqueous dispersion which is applied in the conventional manner to solid pharmaceutical forms. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation-In-Part of U.S. patent application Ser. No. 10/968,318, filed Oct. 18, 2004, which is based on and claims priority to U.S. patent application Ser. No. 10/221,638, filed Jan. 7, 2003, now U.S. Pat. No. 7,147,734, which is based upon International Patent Application PCT US01/07831, filed Mar. 13, 2001, which, in turn, is based on and claims priority to U.S. Patent Application Ser. No. 60/188,979, entitled Bi-Lofted Fire Combustion Modified Batt filed on Mar. 13, 2000.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO A MICROFICHE APPENDIX
[0003] Not applicable.
FIELD OF THE INVENTION
[0004] Disclosed herein are fire combustion modified batts and methods for forming such batts. More particularly, the fire combustion modified batts disclosed herein comprise a blend of nonwoven fibers and charred thermoplastic fibers, such as oxidized polyacrylonitrile (PAN) or FR rayon fibers. The methods include forming a blend of the nonwoven fibers and charred thermoplastic fibers into a web. The charred thermoplastic fibers are fire resistant, and when blended with nonwoven fibers, are relatively easily processed into a batt. A second blend of nonwoven fibers can be formed into a web and layered with the web of charred thermoplastic fibers and nonwoven fibers to form the batt. The fibers of the batt are bonded together with heat, resin or other suitable bonding means and are compressed and cooled to set the batt. The fire combustion modified batt is useful as a fire barrier layer and filling in bedding, upholstery and vehicle and aircraft seats, as insulators for apparel, appliances, walls, aircraft walls, vehicle walls and ducting, as barriers to separate control systems from a heat source, and as components in fire safety gear such as race driver suits, oven and welding mitts, and the like.
BACKGROUND
[0005] Fire retardant barriers are desirable for a wide variety of applications. Products for household and public occupancies such as health care facilities, convalescent care homes, college dormitories, residence halls, hotels, motels and correctional institutions are sometimes governed by regulations which require certain fire resistant characteristics, particularly in bedding and upholstery. Fire barrier components are also needed in apparel, fire safety gear, vehicle and aircraft seating and walls, as insulators for appliances, walls, ducting, as barriers to separate sensitive controls from a heat source and other similar applications where fire safety is a concern. Effective fire barriers minimize the amount and rate of heat released from the barrier upon contact with fire. The rate of beat released is an indication of the intensity of the fire generated from the fire barrier material as well as how quickly the fire spreads. Slowing the spread of fire advantageously increases the amount of response time for a fire victim to safely escape and a fire department to successfully extinguish the fire.
[0006] In the bedding, upholstery and other industries, foams and nonwoven fibers are used in mattresses, sofas, chairs, and seat cushions, backs and arms. Traditionally, urethane foam has been combined with other types of cushioning materials such as cotton batting, latex rubber, and various nonwoven fibers in order to impart desirable comfort, loft and durability characteristics to a finished product. However, urethane foam is extremely flammable and must be chemically treated or coated to impart fire resistant properties to the foam. Alternatively, neoprene foam is used in bedding and upholstery products as it is relatively fire resistant. Both neoprene foam and urethane foam which have been treated for fire resistancy are relatively expensive.
[0007] Synthetic and natural nonwoven fibers also have demonstrated usefulness in the construction of mattresses and upholstery. Such fibers are inherently lightweight and therefore easy to ship, store and manipulate during processing. When subjected to open flame, many synthetic fibers, particularly polymer fibers and specifically dry polyester fibers, tend to melt and drip rather than burn. In addition, polymer fibers can be coated for fire resistance. For example, polymer fibers which have been treated for fire resistance are identified in the industry under the names Trevira FR, Kevlar and Nomex and are considered to be non-flammable.
[0008] Correctional institutions typically use three types of cushion cores for mattresses. The cushion cores include foam, densified synthetic nonwoven fiber which has a density of about 1.5 pounds per cubic foot or greater, and cotton batting. Left untreated, cotton fibers are extremely flammable and burn rapidly. Cotton can, however, be chemically treated, typically with boric acid, to impart fire resistant properties to the cotton. Correctional institutions with heightened fire safety concerns may require their mattresses to meet certain fire safety standards. In these cases, the cushion cores are comprised of neoprene foam or cotton batting which has been treated with boric acid. However, cotton is extremely moisture absorbent. Thus, mattresses comprised of cotton are difficult to maintain in a hygienic condition. Furthermore, cotton mattresses are relatively heavy.
[0009] Oxidized polyacrylonitrile (PAN) fibers, while fire resistant, are difficult to process into batts for use as a barrier layer or filling, particularly in bedding and upholstery applications. The fibers are relatively low in weight and specific gravity making traditional carding methods for forming batts difficult. In addition, oxidized PAN fibers are so-called dead fibers as they have relatively little resilience and loft and are incompressible. In certain applications, in particular for bedding and upholstery, a oxidized PAN fiber batt may be unsuitable where comfort and loft are desired. Oxidized PAN fibers are also black in color and thus may be unsuitable in applications which require a light color beneath a light decorative upholstery or mattress layer.
SUMMARY
[0010] Through significant time and effort, it has been found that the difficulties associated with providing a fire barrier layer could be avoided by the method and batt of the present invention. As will be appreciated by one skilled in the art, the novel method and batt are applicable to a wide variety of products, including as barrier layers and filling materials in bedding and upholstery, as wraps for and replacements of cushion and arms in furniture, vehicle and aircraft seats, as insulators for apparel, appliances, walls, vehicle walls, aircraft walls, ducts and to separate sensitive controls from a heat source, and as components in fire safety gear such as oven or welding mitts, and the like.
[0011] In one aspect, a high loft fiber batt disclosed herein is formed from a blend comprising charred thermoplastic fibers and about 10-15 percent by volume polyester binder fibers, wherein the fiber batt is suitable for use as a fire barrier layer. In an embodiment, the blend of the fiber batt comprises at least 15 percent by volume of the charred thermoplastic fibers. The blend may further comprise at least 15 percent by volume polyester carrier fibers. In an embodiment, the blend comprises about equal amounts by volume of the charred thermoplastic fibers and the polyester carrier fibers. The charred thermoplastic fibers may be selected from the group consisting of oxidized polyacrylonitrile fibers and FR rayon fibers.
[0012] In another aspect, a high loft fiber batt disclosed herein is formed from a blend of at least 15 percent by volume charred thermoplastic fibers, at least 15 percent by volume polyester carrier fibers, and about 10-15 percent by volume polyester binder fibers. In an embodiment, blend forming the fiber batt comprises about equal amounts by volume of the charred thermoplastic fibers and the polyester carrier fibers. The charred thermoplastic fibers may be selected from the group consisting of oxidized polyacrylonitrile fibers and FR rayon fibers.
[0013] In yet another aspect, a high loft fiber batt disclosed herein comprises a blend of about equal amounts by volume of charred thermoplastic fibers and polyester carrier fibers, wherein the fiber batt is suitable for use as a fire barrier layer. In an embodiment, the blend further comprises about 10-15 percent by volume polyester binder fibers.
[0014] Many different products may use the fiber batt as a fire barrier layer thereof. In various embodiments, the products may be selected from the group consisting of vehicle seating, aircraft seating, vehicle wall insulation, aircraft wall insulation, bedding, upholstery and furniture. An aircraft or a vehicle may also use the fiber batt as a fire barrier layer thereof.
[0015] The method of forming the fiber batts disclosed herein comprises blending carrier and binder nonwoven fibers and charred thermoplastic fibers, such as oxidized polyacrylonitrile (PAN) fibers or FR rayon fibers, to form a substantially homogeneous blend of the fibers. The binder fibers have a relatively low melting point and the carrier fibers have a relatively high melting point. While the homogeneous mixture can be any of a number of suitable blends, in one embodiment, the binder fiber can be anywhere in the range of about 5 percent to 50 percent by volume of the blend. The relative percent volume of charred thermoplastic fibers to carrier fibers in the remaining blend volume ranges anywhere from 15 percent to 85 percent. In a preferred embodiment, the relative volume of charred thermoplastic fibers to carrier fibers is about 50 percent to 50 percent. Thus, for a blend having 10 percent by volume of binder fibers and a 50 to 50 percent relative volume of charred thermoplastic fibers to carrier fibers, the volume of charred thermoplastic fibers and carrier fibers in the blend is 45 percent each.
[0016] The blended fibers are formed into a batt by using a garnett machine, cross layers, an air layer or any other suitable batt forming apparatus. In a garnett and cross laying process, the blend of fibers are formed into a web for transporting along a conveyor moving in the machine direction. Successive web layers are layered in the cross direction onto the conveyor in an progressive overlapping relationship by moving one or more reciprocating cross-lappers carrying the web back and forth between a first side of the conveyor and an opposing second side.
[0017] The batt is positioned on an air permeable support and a vacuum is applied through the air permeable support and batt from a first side of the batt to an opposing second side of the batt. The vacuum pressure is sufficient to substantially compress the web into a desired thickness or loft and at a desired density. In an alternative embodiment, the batt is compressed between opposing counter rotating rollers proximate the machine direction and spaced apart a predetermined distance to reduce the thickness and increase the density of the batt. Heat is applied to the web structure at a temperature sufficient to soften the binder fibers but low enough to avoid melting the carrier fibers. The plastic memory of the softened binder fibers is released in their compressed configuration and the fibers fuse to themselves and to the other web fibers to form a batt having interconnected and fused fibers. The batt is cooled in its compressed state to reset the plastic memory of the binder fibers and form a thermal bonded batt having a density and thickness substantially the same as induced in the batt by the vacuum pressure or compression.
[0018] In products which require additional loft, compressibility, resilience and comfort or a light color beneath decorative upholstery, a mattress quilt or other covering for aesthetic purposes, an additional web comprising nonwoven fibers which are light in color can be formed. A surface of the nonwoven web is disposed to a surface of the blended charring fiber web to form a batt which is heated, compressed and cooled together. Alternatively, the charring fiber web and the nonwoven web can be heated, compressed and cooled separately and then disposed together to form the batt.
[0019] The thermal bonded batt has a wide variety of applications in products, depending on its charring fiber content and the density of the batt. For example, a batt having a density of less than 1.5 pounds per cubic foot, defined herein as a high loft batt, can be used as a fire barrier layer in mattresses and border panels of mattresses and as a wrap for or an additional layer to cushion seats, backs and arms in furniture, vehicle and aircraft seats. Such high loft batts may also be used in applications such as insulation for aircraft walls and vehicle walls, and otherwise used in aircraft and vehicle applications. In mattresses and seats having a light colored decorative covering, the batt comprising a layer of nonwoven fibers would be positioned with the light colored nonwoven layer proximate the decorative covering to shield it from the dark color charring PAN fibers. The thermally bonded high loft batt is also suitable as an insulation lining in apparel and fire safety gear such as, for example, in fire fighter jackets and oven mitts for welding or industrial furnace purposes. Further, the high loft batt is suitable as a fire barrier air filter and as an insulator for appliances such as hot water tanks and furnaces. Wall insulation and insulation in recreational vehicle wall cavities are also suitable applications of the high loft batt.
[0020] Batts formed from the method of the present invention having a density of about 1.5 pounds per cubic foot or greater, defined herein as densified, are suitable as a replacement to cushion backs, seats and arms in furniture, vehicle and aircraft seats. The densified batts are also suitable in toppers and filling in mattresses, as well as replacements for mattress cores, such as, for example, the foam or inner springs in mattresses, particularly for use in public occupancies and correctional institutions. Additionally, densified batts are suitable for insulation lining in apparel and safety gear such as race driver suits, and as insulation for walls, furnace wall insulation, and ducting insulation. Densified batts are particularly suitable for sound deadening and thermal transfer applications.
[0021] In yet another embodiment of the method of the present invention, a resin is used to bond carrier fibers and charred thermoplastic fibers to form a fire combustion modified batt of the resent invention. In this embodiment, carrier fibers having a relatively high melting point are blended with the charred thermoplastic fibers to form a homogeneous mixture. While the homogeneous mixture can be any of a number of suitable blends, the charred thermoplastic fibers can be in the range of about 15 percent to 100 percent by volume of the batt and, accordingly, the volume of carrier fibers would be from 85 percent to a negligible amount. Thus, for a blend having 85 percent charred thermoplastic fibers, the volume of carrier fibers would be about 15 percent. The blended charring and carrier fibers can be formed into a web generally according to the garnett method for forming the thermally bonded web described herein. An air laying machine can also be used. Generally, the fibers are introduced into an air stream which carries the fibers to an air permeable support such as a perforated drum which is rotating. Accumulation of the fibers onto the drum surface results in a web formation. A vacuum is applied through the web from one side of the web to the other and through said air permeable support sufficient to reduce the thickness and increase the density of the web throughout the thickness of the web to form a batt. The batt is saturated with a heat curable resin which can additionally comprise fire resistant properties to enhance the fire resistance of the batt. Heat is applied at a temperature sufficient to cure the resin and fuse the fibers to form a batt having a density and thickness substantially the same as during the heating step. For products requiring additional loft, compressibility, resilience and comfort or a light color, a web comprising nonwoven fibers can be formed. A surface of the nonwoven web is disposed to a surface of the charring fiber web to form a batt which is saturated with a resin and heated to cure the resin. Alternatively, the charring fiber web and the nonwoven web can be separately saturated with resin, heat cured and then bonded together by suitable bonding applications. In addition, a relatively thin layer of a nonwoven fiber which is light in color can be bonded to the resin bonded batt for aesthetic purposes where loft, compression and comfort is not required.
[0022] While the resin bonded batt can be high loft, preferably it is a densified batt having a density of about 1.5 pounds per cubic foot or greater. Preferably, the batt is relatively thin, having a thickness in the range of approximately ⅛ inch to approximately 1 inch. The resin bonded densified batt can be used as a fire barrier layer in a mattress, such as for example, directly below the ticking, under the quilt backing, under the quilt panels or borders and above the inner springs. Other suitable applications include as dust covers in mattresses and furniture. The densified resin bonded batt is also suitable as a wrap for cushion seats, backs and arms and for deck padding for furniture and curtain backing material. Further applications include wraps for hot water tanks and furnaces and fire and heat shields in building and vehicle walls.
[0023] While heat and resin bonding methods are discuss, other methods for bonding the fibers of the web to form the batt of the present invention are suitable, such as, for example, needle punching, hydro-entangling and mechanical bonding, and are within in the scope of the present invention.
[0024] The invention is more particularly shown and described in the accompanying drawings and materials included herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] For a more complete understanding of the present invention, and for further details and advantages thereof, reference is now made to the following Detailed Description of the Drawings taken in conjunction with the accompanying drawings, in which:
[0026] FIG. 1 provides a schematic flow chart of a method according to an embodiment of the present invention.
[0027] FIG. 2 provides a schematic top plan view of the processing line for forming a batt according to an embodiment of the method of the present invention.
[0028] FIG. 3A provides a schematic side view of a thermal bonding apparatus according to an embodiment of the method of the present invention.
[0029] FIG. 3B provides a schematic side view of another embodiment of a thermal bonding apparatus according to the method of the present invention.
[0030] FIG. 4 provides a perspective top view of an embodiment of a batt formed from the method of the present invention.
[0031] FIG. 5 provides a perspective top view of another embodiment of a batt formed from the method of the present invention.
[0032] FIG. 6 provides a schematic flow chart of a method according to another embodiment of the present invention.
[0033] FIG. 7 provides a perspective top view of further embodiment of a batt formed from the method of the present invention.
[0034] FIG. 8A is a side cut away view of a traditional mattress.
[0035] FIG. 8B is a side cut away view of a mattress comprising embodiments of batts formed from the method of the present invention.
[0036] FIG. 9 is a side view of a mattress border comprising an embodiment of a batt formed from the method of the present invention.
NOTATION AND NOMENCLATURE
[0037] Certain terms are used throughout the following description and claims to refer to particular components thereof. This document does not intend to distinguish between components that differ in name but not in function.
[0038] In the detailed description and the claims that follow, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . ”.
[0039] The term “inherent-type FR fibers” generally refers to those fibers that resist combustion as a result of an essential characteristic of the fiber.
[0040] The term “non-inherent-type FR fibers” generally refers to those fibers that are generally considered to be non-FR but have been treated with a suitable fire retardant chemical to render the fibers flame resistant.
[0041] The term “charred thermoplastic fibers” generally refers to FR fibers that carbonize into a charred fiber but will maintain a stable physical structure when exposed to flame. Both inherent-type FR fibers and non-inherent-type FR fibers may be charred thermoplastic fibers.
[0042] The term “FR rayon” generally refers to inherent-type FR rayon fibers or non-inherent-type FR rayon fibers.
DETAILED DESCRIPTION
[0043] The method for forming a fire combustion modified batt of the present invention comprises a process for bonding web fibers together to form a batt. The bonding processes discussed herein include a thermal bonding process and a resin saturated curing process. However, other methods may be suitable for bonding web fibers together to form a fire combustion modified batt and thus are within the scope of the invention. For example, needle punching, hydro entangling and mechanical bonds are suitable.
[0044] Turning first to the thermal bonding process which is representatively and schematically illustrated in FIG. 1 , the method comprises the step of blending nonwoven fibers and charred thermoplastic fibers, such as oxidized polyacrylonitrile (PAN) fibers or FR rayon fibers, to form a first web blend. For purposes of illustrating the process and not by way of limitation, the charred thermoplastic fibers of the present invention may be oxidized PAN fibers, such as those marketed under the product name Pyron® by Zoltek Corporation. The oxidized polyacrylonitrile (PAN) fibers are produced from an acrylic precursor. Specifically, the Pyron® brand oxidized PAN fiber is a stabilized form of polyacrylonitrile (PAN) fiber. The stabilization is an oxidation process that converts the polyacrylonitrile (PAN) fiber from a thermoplastic state to a thermoset state.
[0045] The discussion herein illustrates generally the method for forming, and the composition of a particular type of charred thermoplastic fibers, specifically, oxidized PAN fibers, but is not a limitation to the scope of the invention. Other methods and compositions may be suitable for the present invention as would be understood by one skilled in the art. Generally, several types of acrylic polymers with variations in their composition have been used for the production of oxidized PAN fibers. The exact composition of a particular acrylic precursor varies widely. Generally, however, the composition contains a minimum of 85% acrylonitrile and a maximum of 15%, but preferably no more than 8%, comonomers such as methyl methacrylate, methyl acrylate, vinyl acetate, vinyl chloride, and other monovinyl compounds.
[0046] In addition to acrylic as a precursor for the production of carbon fibers, rayon and pitches are also used. The details of the conversion processes used for different precursors are not the same, although their essential features are similar. Generally, the processes involve a stabilizing treatment to prevent melting or fusion of the fiber, a carbonizing treatment to eliminate the non-carbon elements and a high temperature graphitizing treatment to enhance the mechanical properties of the final carbon fiber.
[0047] In the case of PAN fibers, stabilization is carried out by controlled heating of the precursor fiber in an oxidizing atmosphere, for example, in air in the temperature range of about 180° C. to 300° C. The heating rate is usually 1-2° C./minute. However, other temperature ranges and heating rates may be appropriate. Shrinkage can be minimized by stretching the fibers along their axis during the low-temperature stabilization treatment Stretching also produces oxidized PAN fibers with a high degree of preferred orientation along the fiber axis. The stabilization process produces changes in chemical structure of the acrylic precursor such that the product becomes thermally stable to subsequent high temperature treatments. During this process, the fibers change in color to black. The black fibers are carbonized in an inert atmosphere at high temperatures, for example at 1000 to 1500° C. with a slow heating rate to avoid damage to the molecular order of the fiber. The fibers are given a graphitizing treatment at high temperatures for example, above 2000° C. to 3000° C., to improve the texture of the fiber and to enhance the Young's modulus. The strength and the modulus of the fibers can also be improved by hot stretching.
[0048] Generally, the physical characteristics of oxidized PAN fibers are its black color, a moisture content of about 4 to 9 percent, an average fiber diameter of about 11 to 14 microns, a fiber tensile strength of about 180 to 300 Mpa, a fiber elongation of about 18 to 28 percent, a fiber density of about 1.36 to 1.38 g/cc and a fiber length of about 4 to 15 cm. In addition, in the case of Pyron®, the oxidized PAN fibers are thermally stable up to 600° F. The physical and chemical properties may vary depending on the specific manufacturing process.
[0049] The nonwoven fibers of the first blend for the present invention include carrier fibers and binder fibers. The fibers can be natural or synthetic. For example, thermoplastic polymer fibers such as polyester are suitable synthetic fibers. Other fibers can be used depending upon the precise processing limitations imposed and the characteristics of the batt which are desired at the end of the process. For purposes of illustrating the process and combustion modified batt and not by way of limitation, the carrier fiber is KoSa Type 209, 6 to 15 denier, 2 to 3 inches in length, round hollow cross section polyester fiber. Alternatively, the carrier fiber is KoSa Type 295, 6 to 15 denier, ⅕ to 4 inches in length, pentalobal cross section polyester fiber. Other nonwoven fibers are suitable as carrier fibers for the present invention and are within the scope of this invention.
[0050] The binder fiber has a relatively low predetermined melting temperature as compared with the carrier fiber. As used herein, however, the term melting does not necessarily refer only to the actual transformation of the solid polyester binder fibers into liquid form. Rather, it refers to a gradual transformation of the fibers or, in the case of a bicomponent sheath/core fiber, the sheath of the fiber, over a range of temperatures within which the polyester becomes sufficiently soft and tacky to cling to other fibers within which it comes in contact, including other binder fibers having its same characteristics and, as described above, adjacent polyester fibers having a higher melting temperature. It is an inherent characteristic of thermoplastic fibers such as polyester that they become sticky and tacky when melted, as that term is used herein. For purposes of illustrating the process and fire combustion modified batt and not by way of limitation, the binder fiber is KoSa Type 254 Celbond® which is a bicomponent fiber with a polyester core and a copolyester sheath. The sheath component melting temperature is approximately 230° F. (110° C.). The binder fiber, alternatively, can be a polyester copolymer rather than a bicomponent fiber.
[0051] While the homogeneous mixture of nonwoven fibers and charred thermoplastic fibers such as oxidized PAN fibers can be any of a number of suitable fiber blends, for purposes of illustrating the process and first blend, the mixture is comprised of binder finders in an amount sufficient for binding the fibers of the blend together upon application of heat at the appropriate temperature to melt the binder fibers. In one example, the binder fibers are in the range of approximately 5 percent to 50 percent by total volume of the blend. Preferably, the binder finders are present in the range of approximately 10 percent to 15 percent for a high loft batt, and in the range of approximately 15 percent to 40 percent for a densified batt, as those characteristics are discussed below. The relative percent volume of charred thermoplastic fibers to carrier fibers in the remaining blend volume ranges anywhere from 15 percent to 85 percent. In the preferred embodiment, the relative volume of charred thermoplastic fibers to carrier fibers is about 50 percent to 50 percent. Thus, for example, a blend having 10 percent by volume of binder fibers and a 50 to 50 percent relative volume of charred thermoplastic fibers to carrier fibers, the volume of charring PAN fibers and carrier fibers in the blend is 45 percent each. In another example, the volume of charred thermoplastic fibers and carrier fibers in the blend is 45 percent each. In a further example, the volume of charred thermoplastic fibers and carrier fibers having a 50 to 50 percent relative volume is 40 percent each in a blend having 20 percent by volume of binder fibers. In a further example, a blend having 20 percent binder fibers and a 75 percent to 25 percent relative volume mix of charred thermoplastic fibers to carrier fibers, the volume of charred thermoplastic fibers and carrier fibers is 60 percent and 20 percent, respectively. Blends having other percentages of binder, carrier and charred thermoplastic fibers are also within the scope of the invention.
[0052] Referring back to FIG. 1 , the method further comprises an optional step of blending a homogenous second blend of carrier and binder fibers to form a second web. The fibers can be the same as or similar to those of the first web discussed herein, such as, for example, polyester fibers. Other synthetic or natural fibers can be used depending upon the precise processing limitations imposed and the characteristics of the second web which are desired at the end of the process. While the homogeneous mixture of carrier and binder fibers can be any of a number of suitable fiber blends, for purposes of illustrating the process and second blend, the mixture is comprised of binder finders in the range of approximately 10 percent to 20 percent by volume and carrier fibers in the range of approximately 90 to 80 percent by volume. Preferably, the binder finders and carrier fibers are present in the range of approximately 10 percent to 15 percent and approximately 90 to 85 percent by volume, respectively.
[0053] Referring to FIG. 2 , a schematic top plan view of the general processing line 10 for forming a batt of the present invention is illustrated. The following example is directed to the formation of a web in general and thus is applicable to forming both the first web comprising charred thermoplastic fibers such as oxidized PAN fibers and nonwoven fibers and the second web of nonwoven fibers. As discussed above, fibers are blended in a fiber blender 12 and conveyed by conveyor pipes 14 to a web forming machine or, in this example, three machines 16 , 17 , 18 . A suitable web forming apparatus is a garnett machine. An air laying machine, known in the trade as a Rando webber, or any other suitable apparatus can also be used to form a web structure. Garnett machines 16 , 17 , 18 card the blended fibers into a nonwoven web having a desired width and deliver the web to cross-lappers 16 ′, 17 ′, 18 ′ to cross-lap the web onto a slat conveyor 20 which is moving in the machine direction. Cross-lappers 16 ′, 17 ′ 18 ′ reciprocate back and forth in the cross direction from one side of conveyor 20 to the other side to form the web having multiple thicknesses in a progressive overlapping relationship. The number of layers which make up the web is determined by the speed of the conveyor 20 in relation to the speed at which successive layers of the web are layered on top of each other and the number of cross-lappers 16 ′, 17 ′, 18 ′. Thus, the number of single layers which make up the web can be increased by slowing the relative speed of the conveyor 20 in relation to the speed at which cross layers are layered, by increasing the number of cross-lappers 16 ′, 17 ′ 18 ′ or both. Conversely, a fewer number of single layers can be achieved by increasing the relative speed of conveyor 20 to the speed of laying the cross layers, by decreasing the number of cross-lappers 16 ′, 17 ′, 18 ′ or both. In the present invention, the number of single layers which make up the first web of charring and nonwoven fibers and the second web of nonwoven fibers can be approximately the same or can vary depending on the desired characteristics of the fire combustion modified batt of the present invention. Accordingly, the relative speed of the conveyor 20 to the speed at which cross layers are layered and the number of cross-lappers 16 ′, 17 ′, 18 ′ for forming the first web and the second web may be different.
[0054] Referring back to FIG. 1 , the process of the present invention further comprises disposing a surface of the first web in a conforming relationship to a surface of the second web to form the fire combustion modified batt.
[0055] While there are a variety of thermal bonding methods which are suitable for the present invention, one such method comprises holding the batt by vacuum pressure applied through perforations of first and second counter-rotating drums and heating the batt so that the relatively low melting temperature binder fibers in the first web and the second web soften or melt to the extent necessary to fuse the low melt binder fibers together and to the charring and carrier fibers in the first and second webs. Alternatively, the batt moves through an oven by substantially parallel perforated or mesh wire aprons to melt the low temperature binder fibers.
[0056] Referring to FIGS. 2 and 3A , a vacuum pressure method generally comprises using counter-rotating drums 40 , 42 having perforations 41 , 43 , respectively, which are positioned in a central portion of a housing 30 . Housing 30 also comprises an air circulation chamber 32 and a furnace 34 in an upper portion and a lower portion, respectively, thereof. Drum 40 is positioned adjacent an inlet 44 though which the batt is fed. The batt is delivered from the blending and web forming processes described herein by means of an infeed apron 46 . A suction fan 50 is positioned in communication with the interior of drum 40 . The lower portion of the circumference of drum 40 is shielded by a baffle 51 positioned inside drum 40 so that the suction-creating air flow is forced to enter drum 40 through perforations 41 which are proximate the upper portion of drum 40 as it rotates.
[0057] Drum 42 is downstream from drum 40 in housing 30 . Drums 40 , 42 can be mounted for lateral sliding movement relative to one another to facilitate adjustment for a wide range of batt thicknesses (not shown). Drum 42 includes a suction fan 52 which is positioned in communication with the interior of drum 42 . The upper portion of the circumference of drum 42 is shielded by a baffle 53 positioned inside drum 42 so that the suction-creating air flow is forced to enter drum 42 through perforations 43 which are proximate the lower portion of drum 42 as it rotates.
[0058] The batt is held in vacuum pressure as it moves from the upper portion of rotating drum 40 to the lower portion of counter rotating drum 42 . Furnace 34 heats the air in housing 30 as it flows from perforations 41 , 43 to the interior of drums 40 , 42 , respectively, to soften or melt the relatively low melting temperature binder fibers in the first and second webs to the extent necessary to fuse the low melt binder fibers together and to the charring and carrier fibers in the first and second webs.
[0059] REFERRING TO FIG. 3B , in an alternative thermal bonding process, the batt enters housing 30 ′ by a pair of substantially parallel perforated or mesh wire aprons 60 , 62 . Housing 30 ′ comprises an oven 34 ′ which heats the batt to soften or melt the relatively low melting temperature binder fibers in the first and second webs to the extent necessary to fuse the low melt binder fibers together and to the charring and carrier fibers in the first and second webs.
[0060] Referring back to FIGS. 2 , 3 A and 3 B, the batt is compressed and cooled as it exits from housing 30 , 30 ′ by a pair of substantially parallel first and second perforated or wire mesh aprons 70 , 72 . Aprons 70 , 72 are mounted for parallel movement relative to each other to facilitate adjustment for a wide range of batt thicknesses (not shown). The batt can be cooled slowly through exposure to ambient temperature air or, alternatively, ambient temperature air can forced through the perforations of one apron, through the batt and through the perforations of the other apron to cool the batt and set it in its compressed state. The batt is maintained in its compressed form upon cooling since the solidification of the low melt temperature binder fibers in their compressed state bonds the fibers together in that state.
[0061] Referring to FIGS. 1 and 2 , the cooled batt moves into cutting zone 80 where its lateral edges are trimmed to a finished width and it is cut transversely to the desired length of batt.
[0062] Referring TO FIGS. 4 and 5 , an example of batt 100 and batt 200 formed by the thermal bonding method of the present invention is illustrated. Batt 100 is comprised of first web 110 having nonwoven fibers 112 and charred thermoplastic fibers such as oxidized PAN fibers 114 , and second web 120 having nonwoven fibers 122 as discussed previously. Batt 200 is comprised of first web 210 having nonwoven fibers 212 and charred thermoplastic fibers such as oxidized PAN fibers 214 . The weight, density and thickness 102 , 202 of batt 100 , 200 , respectively, are determined by, among other factors, the process of compressing the batt as it is cooled. The ratio of batt density to batt thickness 102 generally dictates whether batt 100 is a high loft batt or a densified bat. For purposes herein, a densified batt has approximately a 2 to 1 or greater ratio of weight in ounces per square foot to thickness in inches. Accordingly, a densified batt has a density of approximately 1.5 pounds per cubic foot or more. Batts have less than a 2 to 1 ratio of weight to thickness and less than 1.5 pounds per cubic foot density are defined herein as high loft bats. For illustration purposes, batt 100 is a high loft batt while batt 200 is densified. Tables I, II and III provide examples of various weights and corresponding thicknesses of batts processed by the thermal bonding method of the present invention.
[0000]
TABLE I*
Weight
Thickness
(oz/sq. ft.)
(inches)
¼-½
½
½-¾
¾
¾-1
⅞
1-1¼
1¼
1¼-1½
1½
1½-1¾
1¾
1¾-2
2
2-2¼
2¼
2¼-2¾
2¾
2¾-3
3
3-3½
3½
3½-4
4
*Suitable blends for the weights and thicknesses in Table I are thermally bonded batts having bicomponent low melt binder fibers in the amount of approximately 10 percent to 20 percent by total volume of the blend. The remaining blend volume comprises a relative percent volume of charred thermoplastic fibers to carrier fibers in the range of approximately 15 percent to 85 percent by relative volume.
[0000]
TABLE II*
Weight
Thickness
(oz/sq. ft.)
(inches)
⅜-¾
¼
¾-1½
½
1⅛-2¼
¾
1⅜-2⅜
⅞
1½-3
1
1⅝-3⅜
1⅛
1⅞-3¾
1¼
2¼-4½
1½
2⅝-5¼
1¾
3-6
2
3¼-6⅜
2⅛
3⅜-6¾
2¼
3¾-7½
2½
4⅛-8¼
2¾
4½-9
3
*Suitable blends for the weights and thicknesses in Table II are thermally bonded batts having bicomponent low melt binder fibers in the amount of approximately 10 percent to 20 percent by total volume of the blend. The remaining blend volume comprises a relative percent volume of charred thermoplastic fibers to carrier fibers in the range of approximately 15 percent to 85 percent by relative volume. The batts are compressed to a ratio of weight (ounces per square foot) to thickness (inches) in the range of about 1.5 to 1 ratio up to about 3 to 1 ratio.
[0000]
TABLE III*
Weight
Thickness
(oz/sq. ft.)
(inches)
4-6¼
3⅛
4⅛-6½
3¼
4⅜-7
3½
4⅝-7½
3¾
5-8
4
5⅛-8¼
4⅛
5¼-8½
4¼
5⅝-9
4½
5⅞-9½
4¾
6¼-10
5
6⅜-10¼
5⅛
6½-10½
5¼
6⅞-11
5½
7¼-11½
5¾
7½-10½
6
7⅝-10⅝
6⅛
7⅞-11
6¼
8⅛-11⅜
6½
8½-10⅛
6¾
8¾-10½
7
8⅞-10⅔
7⅛
9-10⅞
7¼
9⅜-11¼
7½
9⅝-11 1/16
7¾
10-12
8
*Suitable blends for the weights and thicknesses in Table III are thermally bonded batts having bicomponent low melt binder fibers in the amount of approximately 10 percent to 20 percent by total volume of the blend. The remaining blend volume comprises a relative percent volume of charred thermoplastic fibers to carrier fibers in the range of approximately 15 percent to 85 percent by relative volume. The batts are compressed to a ratio of weight (ounces per square foot) to thickness (inches) in the range of about 1.25 to 1 ratio up to about 2 to 1 ratio.
[0063] Referring to FIG. 6 , the method for forming the fire combustion modified batt comprising resin bonding process is representatively and schematically illustrated. Charred thermoplastic fibers, such as oxidized PAN fibers or FR rayon fibers, and carrier fibers are blended to form a first web. Low melt temperature binder fibers are not required as a heat curable binder material is used. The charred thermoplastic fibers and carrier fibers of the blend for the thermal bonding process are suitable for this application as well. For example, Pyron® is a suitable charring fiber, specifically an oxidized PAN fiber, and thermoplastic fibers such as polyester, and more specifically, KoSa Type 209 or KoSa Type 295 are suitable carrier fibers. However, other synthetic and natural fibers can be used depending upon the precise processing limitations imposed and the characteristics of the batt which are desired at the end of the process. While the mixture of charred thermoplastic fibers and carrier fibers in the first web for the resin bonding method can be any of a number of suitable fiber blends, for purposes of illustrating the process, the first blend is comprised of charred thermoplastic fibers, such as oxidized PAN fibers or FR rayon fibers, in the range of approximately 15 percent to 100 percent by volume and corresponding carrier fibers in the range of approximately 85 percent to a negligible amount.
[0064] Referring back to FIG. 5 , the resin bonding method can also optionally comprise a second blend of carrier nonwoven fibers to form a second web. The nonwoven fibers can be the same as or similar to those blended with the charred thermoplastic fibers discussed above, such as, for example, polyester thermoplastic polymer fibers. Other synthetic or natural fibers can be used depending upon the precise processing limitations imposed and the characteristics of the second web which are desired at the end of the process.
[0065] The resin bonding method further comprises forming a first web and a second web, from first and second blends, respectively, using web forming machines such as garnetts, cross-lappers or air laying apparatus. The method also comprises the step of disposing a surface of the first web in a conforming relationship to a surface of the second web to form the batt. While the second nonwoven web provides a lighter color to a surface of the batt and may impart additional loft and comfort, alternatively, a relatively thin layer of a nonwoven facing material may be suitable for reinforcement to the first web of charring and carrier fibers. The web and batt forming steps for the resin bonding method are generally similar to those for the thermal bonding process which details are discussed above. An air laying machine can also be used. Generally, the fibers are introduced into an air stream which carries the fibers to an air permeable support such as a perforated drum which is rotating. Accumulation of the fibers onto the drum surface results in a web formation. A vacuum is applied through the web from one side of the web to the other and through said air permeable support sufficient to reduce the thickness and increase the density of the web throughout the thickness of the web to form a batt.
[0066] Referring back to the schematic of FIG. 6 , heat curable resin is applied to the batt for bonding the web fibers. While there are a variety of applications, generally resin in the form of liquid is sprayed while froth resin is extruded onto the batt. Alternatively, the batt is fed or dipped into a bath of resin. Resins suitable for the present invention are curable by heat and can be any of a variety of compositions. Generally, the resin is comprised of latex or acrylic binders. Additionally, the resin can comprise fire resistant chemicals which further enhance the fire resistance of the finished batt.
[0067] In the application of liquid resin, as the batt moves along a conveyor in the machine direction, the resin is sprayed onto the batt from one or more spray heads which move in a transverse or cross direction to substantially coat the batt. Froth resin is extruded onto the batt using a knife or other means. The batt could also be fed through or dipped into a resin bath. The applied resin is crushed into the batt for saturation therethrough by nip rollers which are disposed along the transverse direction of the conveyor to apply pressure to the surface of the batt. Alternatively, the resin is crushed into the batt by vacuum pressure applied through the batt. The batt moves into an oven heated to a temperature which cures the resin. The batt exits the oven and is cooled. The batt is maintained substantially in its oven state upon cooling since the heat cures the resin which bonds the fibers of the batt together in this state. The batt moves into a cutting zone where its lateral edges are trimmed to a finished width and it is cut transversely to the desired length.
[0068] Referring to FIG. 7 , an example of batt 300 formed by the resin saturated bonding method of the present invention is illustrated. Batt 300 is comprised of first web 310 having carrier fibers 312 and charred thermoplastic fibers 314 and a relatively thin nonwoven layer 320 . The weight, density and thickness 302 of batt 300 are determined by, among other factors, the heating process which cures the resin and fixes the web in this state. Batt 300 can be high loft or densified depending on the processing conditions and the desired batt characteristics. As discussed herein, a densified batt has approximately a 2 to 1 or greater ratio of weight in ounces per square foot to thickness in inches which, in terms of density is approximately 1.5 pounds per cubic foot or more. For illustration purposes, batt 300 is densified. Table IV provides examples of various weights and corresponding thicknesses of batts processed by the resin bonding method of the present invention.
[0000]
TABLE IV*
Weight
Thickness
(oz/sq. ft.)
(inches)
¼-¾
⅛-¼
¾-1½
¼-½
1½-3
½-1
*Suitable blends for the weights and thicknesses in Table IV are resin bonded batts having from 15 percent oxidized PAN fibers up to 100 percent and the remaining volume of polymer carrier fibers.
[0069] Referring to FIGS. 8A and 8B , side views of a traditional mattress and one which incorporates the thermal and resin bonded batts of the present invention are provided. In the construction of a traditional mattress 400 , upper structure 420 positioned over the coil structure 440 includes a quilt panel 422 comprising a cover or ticking 424 , a layer of fiber 426 and a quilt backing 428 . Ticking 424 , fiber layer 426 and quilt backing 428 are stitched together and form quilt pattern 423 . The quilt panel 422 provides loft, comfort and resilience to the mattress 400 . Upper structure 420 of the mattress 400 further comprises a layer of foam filling 430 which imparts durability to the mattress 400 as the foam is relatively stiff as compared to a fiber layer. An insulator 432 separates the foam filling 430 from the coils 440 to minimize the wear of the foam filling 430 which coils 440 may impart. The lower structure positioned under the coil structure 440 is a mirror image of the upper structure 440 and thus is not shown.
[0070] Referring to FIGS. 4 , 5 , 7 and 8 B, mattress 400 ′ which incorporates the fire combustion modified batts of the present invention is shown. Quilt panel 422 ′ of upper structure 420 ′ is comprised of ticking 424 , a resin bonded densified batt 300 having the light colored nonwoven layer 320 proximate the ticking 424 , a thermally bonded high loft batt of charring and nonwoven fibers 110 and a resin bonded densified batt 310 which replaces quilt backing 428 . The resin bonded batt 300 provides fire resistant properties to the mattress near its surface where a flame is likely to contact while providing a light color for aesthetic purposes. The thermal bonded high loft fire combustion modified batt 110 provides sufficient loft, comfort and resilience to effectively replace the fiber layer 426 of the traditional mattress quilt panel 422 while imparting additional fire resistance to the mattress. Upper structure 420 ′ of mattress 400 ′ further comprises a thermally bonded densified batt 200 which replaces foam filling 430 to impart durability to mattress 400 ′. Insulator 432 is replaced with resin bonded batt 310 to enhance the fire resistant properties of mattress 400 . A second thermally bonded densified batt 200 replaces the coil structure 440 .
[0071] Referring to FIG. 9 , a mattress border 500 constructed of a thermally bonded high loft batt 100 of the present invention is provided. Border 500 further comprises ticking 502 , a foam layer 504 and a quilt backing 506 . Batt 100 has a layer 120 of carrier and binder fibers 122 which is proximate ticking 502 and layer 110 of charred thermoplastic fibers 114 and carrier and binder fibers 112 which is proximate the foam layer 504 . Ticking 502 , batt 100 , foam layer 504 and quilt backing 506 are stitched together and form quilt pattern 508 . The thermal bonded high loft fire combustion modified batt 100 provides loft, comfort and resilience to the border while providing fire resistant properties to the border and a light color layer 120 of carrier and binder fibers 122 proximate ticking 502 for aesthetic purposes.
[0072] The thermal and resin bonded batts formed from the methods of the present invention offer substantial advantages as fire barrier layers in a wide variety of products, particularly as mattress components described above. Fire tests conducted on three mattresses which incorporate various batts of the present invention were conducted under the State of California Technical Bulletin 129 Flammability Test Procedure for Mattresses for Use in Public Building, October 1992. A brief description of the test is as follows. A mattress is placed on a support system. Flames from a multi hole burner (fueled by propane at the rate of 12 1/min) impinge on the side of the mattress for a period of 180 seconds. Test observations are made. The tests were performed on mattresses comprising the fire combustion modified batts to determine, among other things, the burning behavior of the mattresses by measuring the response time which the fire barrier layers would provide to a fire victim to safely escape and a fire department to successfully extinguish the fire.
[0073] In a first test, a traditional mattress comprising a quilt panel of ticking, a polyester fiber layer, a urethane foam layer and a quilt backing, two layers of foam and an insulator proximate the coil structure was tested under the California Technical Bulletin 129 . The test ended after 1 minute 27 seconds when unsafe escalating combustion was noted. In a second test, a thermally bonded high loft batt replaced the polyester fiber layer beneath the ticking of a mattress described under the first test. The thermally bonded high loft batt was comprised of a first layer of approximately 10 to 15 percent by volume of binder polyester fibers and the remaining volume was a 50 to 50 percent by volume blend of Pyron® oxidized PAN fibers and polyester carrier fibers. The batt further comprised a second layer of approximately 10 to 15 percent by volume of binder polyester fibers and the remaining volume was carrier polyester fibers. The weight of each layer was approximately 0.5 ounce per square inch for a total batt weight of about 1 ounce per square inch. The second test ended after 18 minutes 40 seconds before unsafe escalating combustion was noted. Thus, the use of a fire barrier layer in a mattress as described in the second test effectively increased the time by 17 minutes 13 seconds over the traditional mattress of the first test. This increase could provide valuable time for a fire victim to escape or a fire department to extinguish the fire.
[0074] In a third test, a densified resin bonded batt replaced the insulator proximate the coil structure of the traditional mattress of the first test. The densified batt was comprised of 50 percent by volume of oxidized PAN fibers and 50 percent by volume of polyester fibers and weighed about ¾ ounces per square foot. The third test ended after 30 minutes 43 seconds before unsafe escalating combustion was noted. Thus, the use of a densified batt formed from the method of the present invention substantially increases the time over the traditional mattress of the first test by 29 minutes 16 seconds.
[0075] The thermal and resin bonded batts formed from the methods of the present invention offer substantial advantages as fire barrier layers in other products as well. For example, a thermally bonded fire combustion modified batt having a density of less than 1.5 pounds per cubic foot, a high loft batt, can be used as a wrap for or an additional layer to cushion seats, backs and arms in furniture, vehicle and aircraft seats. In seats having a light colored decorative covering, the batt comprising a layer of nonwoven fibers would be positioned with the light colored layer proximate the decorative covering to essentially hide the dark color oxidized PAN fiber. The thermally bonded high loft batt is also suitable as an insulation lining in apparel and fire safety gear such as, for example, in fire fighter jackets and oven mitts for welding or industrial furnace purposes. Further, the high loft batt is suitable as a fire barrier air filter and as an insulator for appliances such as hot water tanks and furnaces. Insulation for aircraft walls, automobile walls, building walls and recreational vehicle wall cavities are also suitable applications of the high loft batt.
[0076] Thermal bonded batts formed from the method of the present invention having a density of about 1.5 pounds per cubic foot or greater, densified batts, are suitable as a replacement to cushion backs, seats and arms in furniture, vehicle and aircraft seats. The densified batts are also suitable as replacements for mattress cores, such as, for example, the foam or inner springs in mattresses, particularly for use in public occupancies and correctional institutions. Additionally, densified thermally bonded batts are suitable for insulation lining in apparel and safety gear such as race driver suits, and as insulation for walls, furnaces and ducting applications. Densified thermally bonded batts are particularly suitable for sound deadening and thermal transfer applications.
[0077] Resin bonded batts, preferably densified batts which are relatively thin, having a thickness in the range of approximately ⅛ inch to approximately ½ inch, have applications as dust covers in mattresses and furniture. Densified resin bonded batts are also suitable as wraps for cushion seats, backs and arms and for deck padding for furniture and curtain backing material. Further applications include wraps for hot water tanks and furnaces and fire and heat shields in building and vehicle walls.
[0078] 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. Those skilled in the art will readily see other embodiments within the scope of the invention. Accordingly it is to be understood that the method for forming fire combustion modified batts of the present invention has been described by way of illustration only and not limitation. | A high loft fiber batt is formed from a blend comprising charred thermoplastic fibers and about 10-15 percent by volume polyester binder fibers, wherein the fiber batt is suitable for use as a fire barrier layer. Another embodiment of a high loft fiber batt is formed from a blend of at least 15 percent by volume charred thermoplastic fibers, at least 15 percent by volume polyester carrier fibers, and about 10-15 percent by volume polyester binder fibers. Still another embodiment of a high loft fiber batt comprises a blend of about equal amounts by volume of charred thermoplastic fibers and polyester carrier fibers, wherein the fiber batt is suitable for use as a fire barrier layer. These high loft fiber batts may be used as a fire barrier layer in various different products, including seating and insulation for vehicles and aircraft, bedding, upholstery and furniture. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a structure for expanding or contracting the waist and hip area of an article of clothing having a certain type of waist pocket that is located at the side seam of the garment, with the lowest end of the pocket opening being fastened with an elastic material to allow the waist band to expand while permitting the garment to look properly tailored.
[0003] 2. Description of the Background of the Invention
[0004] There are numerous attempts to create pants which have adjustable or expandable waist structures. The problem has been addressed in numerous patents in the United States. See U.S. Pat. Nos. 1,078,950, Nov. 1913 to Peine; 2,569,853 October 1951 to Grue; 2,599,983 June 1952 to Fanning; 3,098,238 July 1963 to Diamond; 4,596,055 June 1986 to Aach; 5,067,176 November 1991 to Carabillo; 5,544,366 August 1996 to Kato; 6,880,175 B2 April 2005 to Tajima.
[0005] The typical waist expansion structure has had various problems which have made the structure unattractive to consumers. Problems encountered have included shortening of packet depth when expansion of the waist occurs, opening of the pocket excessively allowing contents to be dropped, and what is believed to be the most critical that of puckering of fabric at the pocket area. The puckering problem has made the expanding waist structure unattractive by bringing attention to the very area you did not want examined, and further gives the appearance that the garment is not fitting properly.
[0006] In consideration of these drawbacks, and particularly the resolving of the puckering problem, it is an object of this invention to provide the ability to expand and contract the waist area of a pants garment without puckering of the material in the pocket area.
SUMMARY OF THE INVENTION
[0007] According the present invention, there is provided a waist expanding and contracting structure comprising a waist structure having a front, back and side parts; the front part having a fastener for opening and closing the pants; the side portions having an arrangement whereby it can move two to two and one-half inches at the pocket seam, and is joined with a semi-rigid plastic restraint in the waistband that is affixed to one end of an elastic material which has its other end anchored within the waistband. The movement of the inner portion of the pants are pivoted at the bottom edge of the pocket opening, which is affixed on the inside by an elastic component which can expand in both axises to allow it to accept an angular flexing without any or minimal distortion. The pivoting occurring at the bottom of the pocket opening results in the need for only minor distortion, if any, to the elastic fastening which keeps the outer pocket fabric free from puckering.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 illustrates the side of the pants or garment showing the area where the expansion/contraction structure is located at the pocket seam.
[0009] FIG. 2 illustrates the wire grid and hook assembly which allows expansion/contraction at the waistband by discrete increments.
[0010] FIG. 3 illustrates the pants/garment waistband.
[0011] FIG. 4 illustrates the side pocket seam and the use of a multidirectional elastic joint.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] The innovation is now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding thereof. It may be evident, however, that the innovation can be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate a description thereof.
[0013] The present invention overcomes the disadvantages of the prior art by incorporating a elastic fabric connection at the joining of the pocket to the pants seam and elongating the pocket length to permit the garment to look properly tailored without puffing of the pocket.
[0014] In FIG. 1 we see a view of the side pocket area of the pants or garment 101 . The waistband 111 which is constructed of fabric which is folded over to create a pocket into which a semi-rigid material is placed, attached to the body of a garment 113 , is allowed to contract or expand at the location of the side pocket seam and entrance, the right side 102 meeting the left side 103 .
[0015] To keep the waistband stable and prevent pulling or puckering of fabric, a piece of semi-rigid material such as plastic 104 is placed within the waistband 111 and travels from the left to right side of the pocket seam where the expansion/contraction will occur. The semi-rigid plastic 104 is covered in fabric so as not to be observable. The protruding edge of the semi-rigid plastic 104 is preferably rounded 110 , to allow ease in movement of the semi-rigid plastic through the waistband interior. At contracted position the right side of the pocket opening 102 will be close to or in contract with the left side 103 . The semi-rigid plastic 104 within the waistband 112 will be fully contained within the waistband. The semi-rigid plastic 104 is attached to an elastic band 105 which has one end attached 109 to the semi-rigid plastic 104 and the other end affixed 108 to the body of the waistband 111 . Accordingly, as the waistband is expanded the semi-rigid plastic will allow the waistband to enlarge by moving out of the interior of the waistband stretching the elastic band 105 . The pocket seam will move from the location at 103 to the location 106 or 107 as the waistband is enlarged.
[0016] The movement occurring at the location of the side pocket makes the increase in size to appear as part of the original appearance of the garment. In FIG. 4 we see a detail of the pocket seam 402 being the right and outer side of the pocket and 403 being the left side which will slide beneath the right side 402 . It should ne noted that the pocket length is increased from the standard six inch length to a preferred length of seven inched. This differential in length, which should be between six and one half inches and seven and one half inches, although virtually unrealized by the user of the garment reduces the angular rotation needed for the rotational effect by almost twenty percent. In the expanded positions 406 and 407 the pocket area, due to the pocket elongation, has only to meet the reduced rotation of about fifteen degrees and will appear undisturbed to an observer who will be unable to distinguish the shift in position. The use of a multi-directional elastic 408 , at the joint of the lower edge of the pocket 409 , between the left seam 403 and right seam 402 allows the fabric to shift position rotationally while keeping the fabric flat and presentable. Further, the outer pocket edge 402 does not pucker and distort, keeps a flat appearance. In FIG. 2 an alternate embodiment is shown by using a wire grid 202 in the waistband 201 , which is sewn in 203 , with a hook 205 affixed to the waistband 206 which hook is connects to the grid 202 at various locations. The prior embodiment used the elastic band 105 to allow expansion, but it creates a constant tension which some consumers do not find comfortable. The alternate embodiment using the hood and wire grid allows for adjustment without use of the elastic band. FIG. 2 shows the wire grid 202 and hook 205 in a closed position 204 for the pants or garment.
[0017] FIG. 3 shows the front of the waistband 301 with the front closure 302 . The pants or garment lining is preferably of a nylon to give moving parts greater ability to movably slide as there is less friction encountered. It should be noted that as another embodiment the elastic member 105 can be utilized in conjunction with the wire grid shown in FIG. 2 by having the located at the connection 109 to the rigid material 104 . This would allow a setting of waist size that would be set while allowing variation to occur continuously from the elastic member 105 .
[0018] What has been described above includes examples of the claimed subject matter. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the claimed subject matter, but one of ordinary skill in the art may recognize that many further combinations and permutations of the claimed subject matter are possible. Accordingly, the claimed subject matter is intended to embrace all such alterations, modifications and variations that fall within ‘the spirit and scope of the appended claims. Furthermore to the extent that the term “includes” is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim. | A garment or pants construction that allows the waist of the garment or pants to expand by concealed elastic or fixed settings which enlarge the waistband at the pocket opening. The pocket opening being elongated and using elastic material at the lower end of the pocket opening so that the rotation caused at the changing of the waist size does not cause observable puckering or distortion to the fabric. | 0 |
This is a continuation-in-part application of my copending application, entitled "Load Coil Package With Offset Mounting" and identified as U.S. Ser. No. 877,384, now abandoned filed Nov. 17, 1969.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improved package for encapsulated electrical components, and more particularly, an improved package for encapsulated electrical components used in conjunction with voice frequency cables.
2. Description of Prior Art
To improve the electrical characteristics of cables, such as voice frequency cables used in the telephone communication systems, the cables are spliced at selected intervals and connected with various electrical components, such as load coils. These components are spliced in series with the conductors of a cable at access enclosures or buried plant pedestals, which are generally small and inaccessible. Because of these space limitations it is common practice to encase the plurality of electrical components in one package and then to encapsulate the entire package for protection. One undesirable consequence of encapsulating the entire package is that if one component becomes faulty the entire package must be replaced.
Heretofore, encapsulated electrical components mounted within the enclosure had their terminals disposed vertically relative to the mount centers of the package, so that the terminals were not presented conveniently to the installer. Thus, it was necessary for the installer to "reach around" in the enclosure to make the required splice connections between the cables and the terminals.
Moreover, presently available encapsulated packages have fixed mounting centers and since a plurality of packages are mounted within the same enclosure, each package being mounted separately, it is sometimes difficult to align the mounting studs of the package with the mounting holes of a mounting standard within the enclosure.
Thus, there is a need for an improved package for encapsulated electrical components which is easier to install in access enclosures, buried plant pedestals or in other locations wherein a number of such packages are mounted in a small space.
SUMMARY OF THE INVENTION
Accordingly, this invention provides a new and improved package for encapsulated electrical components which makes installation and routine service easier and therefore, reduces costs. The package comprises a plurality of individually encapsulated electrical components enclosed in a single case which includes a slot through which the leads or terminals of the individual electrical components are accessed. In addition, an adjustable mounting arrangement is provided for the package to minimize the amount of time and effort required by the installer to mount the assembly in the access enclosure. Moreover, the mounting centers are offset rather than normal to the slot through which the coil terminals are accessed in order that the package can be oriented in such a fashion that the leads or terminals face the installer as he connects the leads to the cables. The package also includes a removable lead guard which encloses the coil leads and yet provides easy access to the leads.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of an encapsulated load coil, with the casing partially cut away to show the coil;
FIG. 2 is a partially sectioned side view of the coil shown in FIG. 1;
FIG. 3 is a view of a package made in accordance with the invention, partially assembled, which shows how the individual load coil terminals are offset relative to the bolts which mount the assembly;
FIGS. 4 and 5 are views of a package with different embodiments of removable lead guards provided in accordance with this invention;
FIG. 6 shows a mounting arrangement for a plurality of packages; and
FIG. 7 shows a mounting bar for use in the arrangement shown in FIG. 6.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, a load coil 20 includes a winding 21 wound on, as shown in FIG. 2, a magnetic core 22. The coil 21 is enclosed within a plastic case 23 which includes a body porton 24 and a cover 25. The coil 21 has two sections which are electrically equivalent so that when the coil sections are inserted in series with each side of a two-conductor cable, the impedance characteristic of the cable remains balanced and the effects of longitudinal noise are minimized. The leads of the coil are extended to the outside of the case 23 by two pair of twisted leads 26 and 27. The load coil 20 is completely self-contained and is encapsulated within its own case 23.
The load coil 20 forms no part of this invention and is used to help describe the invention. This invention resides in the package for carrying a plurality of encapsulated electrical components such as load coil 20. For example, other encapsulated electrical components that could be encased are line built-out capacitors, line built-out lattice networks, impedance compensators and gas tube protectors. Each of these electrical components are well-known in the voice transmission field. Built-out capacitors are used to simulate the capacitance of a missing cable. A lattice network of capacitor and resistors balance the line to accommmodate a mixture of wire gauges. Junction impedance compensators, which include an inductor and four capacitors, function as a compensating device for interconnecting cables of different impedance characteristics. Gas tube protectors protect load coils situated in high density lighting areas. There are of course a number of other transmission devices that could be encased in a package constructed in accordance with the principles of the invention.
FIG. 3 shows a partially assembled view of a package 30 in which is contained a plurality of individually encapsulated load coils, such as coil 20 shown in FIGS. 1 and 2, in an end-to-end relation. The coils are contained within a hollow cylindrical plastic case 31 which includes a main body portion 32 and two end covers 33 and 34. With one of the end covers, for example cover 33, removed, a plurality of load coils, such as coil 20, are slid into the case with the magnetic cores of the coils, aligned along the central axis of the case 31. The case 31 has a slot 36 which extends along a line parallel to the central axis of the case 31 for providing access to the coils contained within the case. The slot 36 is long enough to permit the leads of all the load coils to be passed through the slot to the outside of the case and routed to one end thereof as shown in FIG. 4, whereby electrical connections can be made to the coils.
The case is of a flexible elastic material, for example, plastic, so that if it is necessary to replace any one of the coils, such as coil 20, the coil 20 can be quickly removed from the case by pulling the coil through the slot 36 without removing the end covers 33 and 34. To facilitate this technique for coil replacement, the width of the slot 36 is made approximately five to ten per cent less than the diameter of load coil 20. In this way, an individual coil may be serviced without disturbing any of the other coils of the assembly.
A portion of the case body 32 on one side of the slot 36 is rolled back to form a flange 39 which is used to prevent sharp bending of the lead wires 26 and 27 of the coils. For mounting the package 30, a mounting means is provided comprising a guide track 54 and a pair of mounting bolts 55 and 56 with square heads in sliding engagement with the guide track 54.
The position of the headed mounting bolts 55, 56 is adjustable relative to one another to simplify the mounting of the load coil assembly within the enclosure. The heads of the bolts 55 and 56, positioned within the guide track 54 are movable within the track 54 along the length of the case. Thus, the mounting centers for the package 30 are not fixed, but are adjustable whereby the mounting of the package 30, particularly in hard-to-reach locations, is made easier.
The slot 36 through which the leads of the coils pass to the outside of the case, is disposed along a line parallel to the longitudinal axis of the case, and the mounting centers of the assembly as defined by the longitudinal axis of bolts 55 and 56, are offset relative to a line which lies in a plane which passes through the longitudinal axis of the case and the center of the slot 36. Thus, when the package 30 is bolted to a mounting standard (not shown), the coil leads will always be facing the installer.
Each end such as cover 33 includes a guide member 37 which engages the mounting guide track 54 to position the cover 33 on the case. One or both of the end covers 33 and 34 may be permanently attached to the case body 32 by heating to form a bond between the covers 33 and 34 and the case body 32 or by using a suitable adhesive.
In FIG. 4, there is shown a second embodiment illustrated as package 40 which includes a lead guard 41. The guard 41 includes hooked end portions 44 and 45 which are slidably engageable with the flanges 46 and 47, respectively, on the case 43. With an end cover 48 of the case 43 removed, the lead guard 41 is slipped over the slot 50 and the exposed portions of the coils 51, including leads 52, so that when the guard 41 is in place, the slot 50 is covered and the coils 51 are enclosed. When the cover 48 is replaced, the guard 41 is held in place by the end covers 48 and 49. Through the use of the removable lead guard 41, the coil leads 52 are protected and yet can be quickly exposed by removing an end cover, such as 48, and sliding off the lead guard 41.
The center portion 42 of the lead guard 41 is bowed away from main body of the case 43 to accommodate a plurality of layers of wires, shown generally at 52. The installer may bring half of the wires out from the end of the guard 41 adjacent cover 48, or the end adjacent cover 49. Package 40 also includes mounting members 55-56 which provides adjustment centers for mounting the package.
A third embodiment of a package constructed in accordance with the present invention is shown in FIG. 5. The package 57 is similar to the package 40 of FIG. 4 but uses a flat lead guard 50. Case 43 and covers 48 and 49 and other features of the package 57 that are similar to those of the package 40 of FIG. 4 have been given the same reference numeral. The flat lead cover 58 is generally used when only a few load coils are encased and fewer leads 60 are to be protected.
Referring to FIG. 6, there is shown an arrangement for mounting three packages 68, 69 and 70, to a standard 65, through the use of a mounting bar 67, shown in FIG. 7. Load coil packages 68-70 may be similar to assemblers 40, and 57 described above and include lead guards 80-82 or may be without lead guards as is the load coil package 30 of FIG. 3.
The mounting bar 67, which may be aluminum, is formed with "T-shaped members" 71, 71 and 73, formed integrally on junction 75. The dimensions of the "T-shaped" members 71-73 are commensurate with the dimensions of the guide tracks 83, 84 and 85 of the cases of packages 68-70, respectively. The mounting bar 67 includes a track 77 formed by a "C-shaped" channel member 78 formed integrally with the mounting bar 67. The mounting bar 67 permits three packages 68-70 to be held together and be mechanically interconnected and mounted on a standard 65 as a single assembly by the use of the headed bolts slidably movable in track 77. Only one mounting bar 67 is required to hold the three packages 68-70 together. The mounting bar 67 could be modified to hold more than three packages together for mounting.
As can be seen in the front view of the assembly shown in FIG. 6, when the load coil packages 68-70 are mounted together by means of bar 67, the lead access areas, indicated by lead guards 80, 81 and 82 of the load coil packages 68-70, are all disposed so as to be readily accessible from the front of the access enclosure. | .[.A package for holding a plurality of encapsulated electrical components comprising a cylindrical case having a lengthwise slot through which the leads of the components extend, and an adjustable mounting means carried by the case which is offset from the lengthwise slot..].
.Iadd.In a telephone communication system there is provided a plurality of individual encapsulated electrical components for improving the voice transmission which are held in electrical disconnected relationship and in an end-to-end relation in an elongated hollow, flexible elastic case having a continuous slot with the width of the slot and the elasticity of the flexible case cooperating to allow a selected electrical component to be manually removed through the slot. An electrical component assembly which is capable of being disposed within the case and a mounting bar for mounting a plurality of the electrical component packages are also disclosed. .Iaddend. | 7 |
This application claims Paris Convention priority from DE 199 02 629.7 filed Jan. 23, 1999 the complete disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
The invention concerns a light for a vehicle having a reflector, at least one neon lamp and a cover plate.
DE 94 13 286 U1 describes an auxiliary brake light for an automobile which is disposed on the inside rear shelf of the vehicle and is directed towards the rear window. A curved fluorescent tube can be disposed within the lighting housing. Although fluorescent tubes can effect a very high light yield, the neon lamp is visible as a bright stripe and the light intensity decreases rapidly with distance. In addition, the connector elements must be covered with additional components. Another disadvantage is that, for insertion or exchange of the fluorescent tubes, either the cover plate has to be removed or the entire lamp must be dismounted.
WO-A-98 12 471 describes a rear light in which a plurality of fluorescent tubes are disposed in front of the reflector.
SUMMARY OF THE INVENTION
Departing from DE 94 13 286 U1 it is the underlying purpose of the invention to provide a light in which a neon lamp can be easily inserted and with which the neon lamp can be exchanged in a simple fashion.
This purpose is achieved in accordance with the invention with a light of the above mentioned kind in that the reflector is provided with a shield for the direct light travelling towards the cover plate.
This shield prevents the neon lamp from being visible through the cover plate as a bright stripe. In addition, this shield prevents the neon lamp from blinding other drivers and passengers due to its high light intensity and associated light density. The illumination and the overall lighting effect is thereby improved. Possible lights include rear lights, brake lights, blinkers, backup lights etc.
A preferred improvement provides that the neon lamp can be inserted into the reflector from the backside thereof. The reflector has an opening having a shape adapted to that of the neon light through which the neon light can be completely or partially inserted into the reflector from the rear, i.e. from the backside. This has the substantial advantage that the cover plate must not be detached from the reflector in order to insert or exchange the neon lamp and the cover plate can even be permanently mounted to the reflector. An additional advantage of the light in accordance with the invention, is that the neon lamp can be easily attached to the reflector from inside the vehicle and even optionally without the use of tools. In another embodiment, the neon lamp can be inserted from the front.
A further improvement provides that the shield is configured to reflect light at the side facing the neon lamp, in particular, to deflect the light towards the reflector. The light directly incident from the neon lamp onto the shield is deflected by the shield, in particular by its reflector, towards the main reflector of the lamp so that this light can be utilized and is not destroyed behind the cover.
In accordance with the invention, the shield is connected to the reflector via one or a plurality of braces. The braces have the advantage that the large length of the neon lamp is associated with nearly no shadowing.
The shield is advantageously formed on the reflector and is preferentially integral therewith. In this fashion, the shield and the reflector can be simultaneously evaporation coated and must not be subsequently processed further. The integral configuration has the additional advantage that the shield is exactly positioned in or on the reflector.
In an embodiment of the invention, the shield is partially permeable to light so that a black stripe is not produced in the cover. The partial optical permeability of the shield can thereby be selected in such a fashion that the intensity of the light passing through the shield is as large as the intensity of the light reflected from the reflector.
An improvement provides that the shield has a surface structure on the side facing away from the neon lamp and/or is tinted. This facilitates optical or design effects.
In an additional embodiment, the reflector has a corrugated or stepped reflector surface. Instead of a parabolic shape, the corrugated reflector can reflect the light towards the cover plate in dependence on the configuration of the corrugations. This can also be achieved using a stepped reflector surface.
The back side of the reflector preferentially has holding elements and or plug contacts for the neon lamp. The plug contacts for the neon lamp are thereby covered so that no additional covering is necessary. The holding elements can be used to precisely position and mount the tubes of the neon lamp. The tubes can e.g. directly seat on the holding elements.
Further advantages, details and features of the invention can be extracted from the dependent claims as well as from the following description in which particularly preferred embodiments are described in detail with reference to the drawing. The features disclosed in the description and the claims and shown in the drawing can be important to the invention individually or collectively in arbitrary combination.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a plan view of a reflector having a schematically indicated neon lamp;
FIG. 2 shows a cut through the reflector II—II in accordance with FIG. 1;
FIG. 3 shows a cut III—III through the reflector in accordance with FIG. 1, showing plug contacts;
FIG. 4 shows a cross section through a first embodiment of a rear light;
FIG. 5 shows a cross section through a second embodiment of a rear light; and
FIG. 6 shows a cross section through a third embodiment of a rear light.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The embodiment FIG. 1 shows a reflector, indicated in its entirety with 1 , comprising two reflector shells 2 and 3 . The reflector shell 2 is shown in an enlarged representation in FIG. 2 . As can be seen in FIG. 2, both reflector shells 2 and 3 are curved with a parabolic shape so that the light from a neon lamp 4 is deflected into substantially parallel beams 5 (FIG. 2 ). The neon lamp 4 has two connector elements 6 and 7 and comprises a curved section 8 . The reflector 1 comprises covers 9 through 12 proximate the connector elements 6 and 7 as well as in the region of the curved section 8 which cover the connector elements 6 and 7 and the curved section 8 .
A shield 13 and 14 extends between each of the covers 9 and 11 as well as 10 and 12 . Linear sections 15 and 16 of the neon lamp 4 are covered by the shields 13 and 14 in a direction of a cover plate (not shown). This prevents the neon lamp 4 light from being directly incident on the cover plate. In addition, the neon lamp 4 cannot be seen from the outside, i.e. through the cover plate. The shields 13 and 14 are connected to the reflector shells 2 via narrow braces 17 . The width of the braces 17 is selected in such a fashion that only negligible regions of the linear section 15 and 16 of the neon lamp 4 are covered. The braces 17 also firmly connect the shields 13 and 14 are to the reflector shells 2 and 3 so that they can be handled together therewith.
Output openings are located between the shield 13 and the reflector shell 2 as well as between pairs of braces 17 through which the light from the neon lamp 4 can escape to be incident on the reflector surface 18 where it is deflected into substantially parallel beams 4 . The light incident on the side of the shield 13 facing the neon lamp 4 is deflected by a second reflector 19 so that this light likewise passes through the openings and can be used. Towards this end, this reflector 19 has a light deflecting geometry.
As can also be seen in FIG. 2, the braces 17 seat on the surface of the neon lamp 4 to thereby hold the neon lamp 4 in a defined position.
FIG. 3 shows the two reflector shells 2 and 3 in a sectional representation. The two covers 9 and 11 cover the two connector elements 6 and 7 of the neon lamp 4 .
FIG. 4 shows a section of a first embodiment of the invention in accordance with FIGS. 2 and 3. One can clearly see that the rear side of the reflector 1 is accessible after removal of a cover shell 20 from the rear light 24 . Light bulbs 21 and 22 as well as elements 23 for power supply are disposed on the cover shell 20 . The back side is covered by a cap having an integral fluorescent lamp ballast 26 . After the cap 25 is removed, the neon lamp 4 is freely accessible and can be inserted into and removed from the back side of the reflector 1 . Exchange of the neon lamp 1 is thereby simple and straight forward.
FIG. 5 shows a second embodiment with an additional recepticle 27 , provided between the two reflector shells 2 and 3 , for a linear section of a neon lamp 4 . FIG. 6 finally shows a third embodiment with which the reflector 1 has a corrugated reflector surface 18 , wherein the corrugated contours are configured in such a fashion that they deflect the light incident thereon towards the cover plate 28 in substantially parallel beams 5 . This allows individual design goals to be taken into consideration.
In any event and in all embodiments, the neon lamp 4 is covered by shields 13 and 14 so that the radiation from the neon lamp 4 is not directly incident on the cover plate 28 . | The invention concerns a light having a reflector, at least one neon lamp, and a cover plate, wherein the light is provided with a shield for shielding the direct light of the neon lamp travelling towards the cover plate. | 5 |
BACKGROUND OF THE INVENTION
[0001] Modem looms place increasing demands on the precision of components. This applies especially to the heddle shafts. They are operating at very high speeds during the weaving operation. It is absolutely necessary that heddle shafts are guided in a sufficiently precise manner to avoid added stress. However, it is an essential prerequisite that the heddle shafts themselves are manufactured in a sufficiently precise manner. Additionally, they must be constructed in such a way that the side struts may be simply disassembled for the insertion of heddles and re-assembled thereafter by having the original precision. Multiple changing of components in weaving mills has the consequence that shaft rods and side struts will be mixed up. Components being manufactured with higher precision solve this problem only to a small degree since larger differences from one production lot to the other is unavoidable. A novel constructional solution is thereby necessary. Comer edge connections from prior art do not, however, fulfill the requirements.
[0002] Various attempts are known from the prior art. Since it may be assumed that precise alignment of side struts was not the object of the proposed solution at the time of their creation, one must not be surprised that the precision reached up to now is not sufficient for current demands. According to that disclosed in Swiss patent 427 688 there cannot be achieved sufficient precision merely because of the tolerance or play which the bolt requires within the threads. As disclosed in U.S. Pat. No. 3,180,367 the bolts 22 shown therein would need to be dowel bolts fitted into correspondingly precise borings. However, such a solution is not achievable because of the stress that is currently placed on heddle shafts. The marginal portions 13 according to this prior art patent are either no longer in existence or they must not be weakened anymore by longitudinal borings. The invention disclosed in Japanese patent 56-39 478 has no elements that would make sufficiently precise alignment possible. The same applies for Japanese patent 56-14 3286 and Russian patent 105 143.
[0003] A solution for this problem is proposed in Japanese patent 37-31581. However, this is inapplicable for modem heddle shafts based on a completely different shaft profile in its design.
SUMMARY OF THE INVENTION
[0004] It is therefore an object of the present invention to propose a comer connection for a heddle shaft that assures simple and precise alignment of side struts and shaft rods in one place at all times, and which additionally fulfills present demands in total to which the heddle shafts are exposed. The invention allows the exchange of side struts and shaft rods with one another while nevertheless maintaining the necessary precision during, assembly without extraordinary measures. The main objective is to achieve an alignment of the side struts and the shaft rods in one plane in a simple and repeatable manner.
[0005] A corner connection of a heddle shaft is provided according to the invention whereby on or in the shaft rod there is at least a first guide surface provided, which extends nearly parallel to the longitudinal axis of the shaft rod and which engages with a positive fit a second guide surface extending along a projection of the side strut at least nearly parallel to the shaft rod or perpendicular to the side strut.
[0006] The solution according to the invention has also the object to provide a comer connection which allows simple detachment of side struts and which always assures the same positioning precision of components during assembly. The positioning precision relates thereby to the twisting of components against one another and their alignment in one plane. Positioning is achieved according to the invention whereby guide surfaces are placed on the ends of the shaft rods and on each projection of the side strut, respectively, which ensures precise positioning as soon as said guide surfaces engage one another. The same precision in positioning is also achieved after detachment of the connection and reassembly of the components.
[0007] In a preferred embodiment, guide surfaces required for the side struts are placed directly on the projection of the side strut, which engages the shaft; whereby the guide elements, having the cooperating guide surface (s), are mounted or attached in or on the shaft rod by means of rivets, for example. The guide surfaces of the elements on the shaft rod are designed in the shape of ridges, whereas the ones on the counter-support are designed as grooves, for example. An exactly converse configuration is possible, of course, and it would not change the inventive effect. This effect is achieved in that the guide surfaces interlock with positive fit.
[0008] The projection of the side strut is inserted into the shaft rod to couple the shaft rod to the side strut. The guide surfaces of all components come thereby into contact with one another. The guide elements attached to the shaft rod may be drawn together by means of a tensioning bolt to secure the coupling whereby the side struts are held by clamping of their projections. A slot may be placed parallel to the longitudinal axis of the shaft rod and between the two guide elements to achieve the necessary flexibility on the shaft rod. In addition, one of the guide elements may be provided with threads for a tensioning bolt. The projection of the side strut may be provided with a cavity on the inside, extending parallel to the plane of the assembled shaft whereby the space of the cavity extending cross-wise to the plane is slightly larger than the diameter of the bolt. The depth of the cavity is sized in such a manner that the tensioning bolt may be rotated freely in the assembled condition of the side strut and shaft rod. This cavity, which is open toward the shaft rod, makes it possible to separate the side strut from the shaft rod while the tensioning bolt is slightly loosened so that the tensioning bolt does not have to be completely unscrewed from the threads and removed from the shaft rod. Loosening of the tensioning bolt is thereby prevented. Assembly of the side strut and shaft rod is possible in the same fashion. The bolt has to be rotated only slightly thereby.
[0009] Additional preferred embodiments of the comer connection defined in the invention are characterized in the dependent claims.
[0010] The invention is now explained in more detail by examples in reference to accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 is a front elevational view an embodiment of the corner connection according to the invention;
[0012] [0012]FIG. 2 is a view similar to FIG. 1 of another embodiment of the corner connection of the invention;
[0013] [0013]FIG. 3 and FIG. 4 are perspective views of the so-called stop element of FIG. 1 and FIG. 2, respectively;
[0014] [0014]FIG. 5 is a sectional view taken substantially along the line A-A of FIG. 1, rotated 180°, showing the guide surfaces provided for interlocking with positive fit;
[0015] [0015]FIG. 6 is an expanded view, in perspective, of the elements of FIG. 3 and FIG. 4 together with a side strut;
[0016] [0016]FIG. 7 is a schematic front elevational view of a heddle shaft comprising shaft rods and side struts incorporating the invention; and
[0017] [0017]FIG. 8 is a view similar to FIG. 6 of an alternatively structured side strut.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Shown in FIG. 1 is a hollow heddle shaft 1 , partly broken away, onto which the heddle shaft support bar 9 is attached. A side strut 2 , partly broken away, has a projection 11 extending into an end of hollow shaft 1 for engagement between two guide elements, which are firmly arranged in or on the shaft 1 , having a stop element 3 and a threaded plate 4 . The projection 11 of the side strut is arrested between stop element 3 and threaded plate 4 , which are attached in or on the shaft rod 1 , whereby the stop element 3 is urged toward the threaded plate 4 . This is made possible because the shaft rod has a specific flexibility by the provision of a slot 6 at the end section of the shaft rod. The stop element 3 is provided additionally with a machined surface 10 (see also FIG. 3), which serves to position the side strut 2 in longitudinal direction of the profile of shaft 1 . According to the embodiment in FIG. 1, there is also a drive element 7 attached to the side strut 2 by means of riveting 8 .
[0019] [0019]FIG. 2 shows a corner connection configured essentially the same as in FIG. 1, whereby the stop element 3 ′ is designed considerably larger so that a drive element 7 ′ for the heddle shaft may be fastened directly to stop element 3 ′ instead of being fastened to side strut 2 as in FIG. 1, for example. Also, the tensioning bolt 5 may be arranged at an angle to the longitudinal axis of the shaft profile 1 instead of vertically as shown in FIG. 1.
[0020] [0020]FIG. 3 is a perspective view of a typical embodiment of a guide element or stop element 3 according to FIG. 1 shown rotated 180°. The positioning elements or surfaces 10 and 14 are clearly visible. The surface 10 is essentially a stop surface for the side strut. The function of guide element 14 is explained in more detail in FIG. 5, stop element 3 being identified therein by reference numeral 20 for clarification.
[0021] Holes 13 may extend through stop element 3 for use as rivet holes for attachment of stop element 3 in the cavity of shaft rod 1 . Other fastening means such as welding or gluing may be used, depending on the type of material used. Hole 12 serves as a passage for a tensioning bolt 5 according to FIG. 1.
[0022] [0022]FIG. 4 is a perspective view of a typical embodiment of a guide element or stop element 3 ′ shown in FIG. 2. The positioning elements 10 ′ and 14 ′ are better visible therein. The surface 10 ′ is essentially a stop surface for the side strut. The function of element 14 ′ is explained in more detail in FIG. 5 and it is identified therein by reference numeral 22 for clarification.
[0023] Holes 13 ′ may extend through element 3 ′ for use as rivet holes for attachment of stop element 3 ′ in the cavity of the shaft rod 1 . Other fastening means such as welding or gluing may be used, depending on the type of material used. The through hole 12 ′ serves as a passage for tensioning bolt 5 according to FIG. 2.
[0024] [0024]FIG. 5 shows a schematic cross-sectional view taken through the positioning element of the corner connection of the invention along the line A-A in FIG. 1. The sectioned stop 14 of the stop element 3 from FIG. 3 is identified by reference numeral 20 for clarification. It is provided with the surfaces 23 and 23 ′ for positioning in a Y-direction and with the surfaces 24 and 24 ′ for positioning in an X-direction of the guide or stop element 3 of FIG. 3.
[0025] The surfaces 25 and 25 ′ of section 21 serve as counterparts that respectively come into contact with the surfaces 23 and 23 ′, and surfaces 26 and 26 ′ of section 21 respectively come into contact with surfaces 24 and 24 ′. The surfaces 28 and 28 ′ as well as 27 and 27 ′ are also located on section number 21 , which is a section through the projection 11 of the side strut 2 according to FIG. 1. And, surfaces 28 and 28 ′ as well as 27 and 27 ′ make contact with the cooperating surfaces 30 and 30 ′ or 29 and 29 ′, respectively, which extend in a longitudinal direction on threaded plate 4 according to FIG. 1, which is identified here in the section by reference numeral 22 .
[0026] The surfaces 30 and 30 ′ on the sectioned threaded plate serve for positioning in a Y-direction the projection 11 of the side strut 2 according to FIG. 1 and the surfaces 29 and 29 ′ for positioning in an X-direction, the projection being identified by reference numeral 21 in the cross-section.
[0027] The aforedescribed positioning surfaces acting between projection 11 and threaded plate 4 and stop element 3 of FIG. 1 are the same in shape and function as the positioning surfaces acting between projection 11 and threaded plate 4 and stop element 3 ′ of FIG. 2.
[0028] With sufficiently large contact areas of the surfaces 23 , 23 ′; 24 , 24 ′, 25 , 25 ′ and 26 , 26 ′, the symmetrically arranged surfaces 27 , 27 ′; 28 , 28 ′; 29 , 29 ′ and 30 , 30 ′ may be eliminated. Since precise machining of the surfaces becomes, nevertheless, more difficult and costly with its increasing size, the configuration shown in cross-sectional view in FIG. 5 is preferred.
[0029] The cooperating surfaces 23 , 23 ′ or 30 , 30 ′ as well as 24 , 24 ′ or 29 , 29 ′ reliably prevent twisting of the side strut relative to the shaft rod—even when these surfaces are small in size. This is an important function since an even surface of the entire shaft layout can be assured only through this function. All embodiments known from prior art, having projections on the side strut engaging the cavity of the shaft rod, do not fulfill this requirement since sufficiently precise machining inside the cavity of the shaft rod would have been very difficult and very costly. The guide elements may, according to the invention, be manufactured in a precise manner with simple means and may, above all, be reproduced in large numbers at low manufacturing cost.
[0030] An additional un-illustrated embodiment of the surfaces 24 , 24 ′; 26 , 26 ′; 29 , 29 ′ and 27 , 27 ′ is possible whereby these surfaces are angled to facilitate dovetail engagement between sections 21 , 20 and 21 , 22 .
[0031] The embodiment shown in FIG. 2 is preferably used when drive elements 7 ′ are to be fastened to the outer end of the shaft rod 1 . In that case, the shape of the stop element 3 ′ assures that the drive forces, which act upon element 7 ′, are directly transferred to the side strut 2 or its projection 11 so that the shaft profile 1 does not have to transfer such force and be additionally stressed thereby. The same application can also be used with a bolt 5 , which is arranged perpendicular to the longitudinal axis of the shaft rod 1 as shown in FIG. 1, as long as this is allowed by the position of the drive element. This will always be the case whenever the distance to the side strut 2 is sufficiently large.
[0032] [0032]FIG. 6 is a perspective illustration of the elements 3 and 4 from FIG. 2—together with a perspective and somewhat simplified illustration of the side strut 2 with a projection 11 thereof to clarify interlocking of the three elements. The cavity 18 for the bolt 5 is also visible therein. The depth of the cavity is at the most about three-fourths the length of projection 11 .
[0033] [0033]FIG. 7 is a schematic illustration of a heddle shaft comprising top and bottom shaft rods 1 and 1 ′ and the side struts 2 and 2 ′. The present invention relates to the connection of the shaft rods 1 and 1 ′ to the side struts 2 and 2 ′.
[0034] Shaft rod 1 may be of shaped aluminum or steel. And, side strut 2 may be of shaped aluminum or steel pipe. Further, the side strut may be of unitary construction as shown in FIGS. 1 and 2, or may be constructed of parts welded together as at 31 shown in FIG. 8. Otherwise, the shaft rod and/or the side strut may be of a fiber-reinforced synthetic material or a combination of various metals and fiber-reinforced synthetic material, without departing from the invention. | In a connection of a shaft rod to a side strut of a heddle shaft there is at least one guide surface provided in or on the shaft rod. The guide surface extends substantially parallel to the longitudinal axis of the shaft rod. The guide surface engages with a positive fit to a second guide surface extending along a projection of the side strut substantially parallel to the shaft rod or perpendicular to the side strut. | 3 |
RELATED CASES
The present application is related to U.S. patent application Ser. No. 11/030,649, filed Jan. 6, 2005 and entitled “Rocket Propelled Barrier Defense System,” now abandoned, which is a continuation-in-part of U.S. patent application Ser. No. 12/082,237, filed Apr. 9, 2008 and entitled “Rocket Propelled Barrier Defense System,” now U.S. Pat. No. 8,122,810, all of which are incorporated herein by reference.
TECHNICAL FIELD
This invention relates generally to defensive systems for use against ballistic threats and missiles. Specifically the invention relates to ultra-rapid aiming and launching of defensive countermeasures including non-fratricidal countermeasures into the flight path of oncoming threats such as ballistic missiles and Rocket-Propelled Grenades (RPGs).
BACKGROUND
The threat posed by small ballistic weapons such as rocket-propelled grenades (RPGs) and shoulder fired missiles is significant and well documented. Attacks are routine and result in substantial losses of lives and equipment. The constant threat of RPG attack is a significant tactical advantage for insurgent forces. Other missile types, such as the Soviet SA series, and shoulder-fired Stinger are serious threats worldwide. Emerging threats such as the so-called “lob bomb” are similar in nature to the RPG and add a new dimension to this problem.
While attacks on vehicles on the ground are most prevalent, aircraft are also frequently targeted. The RAND corporation has published a report entitled “Protecting Commercial Aviation Against the Shoulder-Fired Missile Threat” (J. Chow, et al.), which is incorporated herein by reference, provides a comprehensive survey of existing and future missile threats as well as the existing countermeasures. The report concludes that there is a pressing need for a practical, reliable defense system for use against these threats. The threat is greatest for military aircraft. RPG and other shoulder-fired missile attacks on military aircraft are common, and include attacks on both fixed-wing and VTOL hovering aircraft.
Detecting Threats
Much work has been done on vehicle-mounted systems for the detection and localization of ballistic threats after they have been fired and are traveling toward their prospective target vehicle or aircraft. In general these systems rely on infra-red detectors and/or microwave radar to detect the firing of an RPG or a bullet. The systems generally provide the host vehicle with data on the type of threat and the direction that it was fired from. U.S. Pat. No. 6,980,151 to Mohan, “System and Method for Onboard Detection of Ballistic Threats to Aircraft,” describes a radar system and signal processing method for detection of missiles. U.S. Pat. No. 7,046,187 to Fullerton, et al, “System and Method for Active Protection of a Resource,” describes the use of an ultrawideband radar for threat detection. Commercially developed threat detection systems, such as Mustang Technologies “Crosshairs” RPG detection countermeasure system and Radiance Technologies “WeaponWatch” system, provide warning and directional data on fired threats. The major objective of these systems is to enable the target vehicle to quickly and accurately return fire in response to an attack. For example, in the case of a sniper attack, the target vehicle could fire back at the precise location that the bullet came from, hopefully preventing additional shots from being fired on the host vehicle. Return fire could be accomplished by, for example, a gun mounted in a turret that is aimed automatically by a system that utilizes the threat directional data provided by the threat warning system. Such a system allows rapid return fire in the case of an attack.
In the case of attack by RPG however, the objective of a defensive system should be to not only return fire, but to fire one or more countermeasures into the pathway of the approaching RPG thus stopping the RPG before it hits the target vehicle. The term “countermeasure” as used herein is broadly construed to reference any type of projectile that is capable of stopping, deflecting, or detonating an RPG or other ballistic missile or projectile before it hits its intended target. The term “projectile” in this case is construed to reference an object that can be propelled, fired and/or launched in any conventionally understood manner.
Therefore, in addition to rapid detection and data processing of a threat, which the above systems generally provide, the key to achieving an effective projectile defense system is a system that aims and fires countermeasures very quickly. For example, a typical RPG attack occurring from a range of about 50 meters allows less than one-half second between the time the RPG is fired until it strikes its target. From this it may be seen that extremely rapid aiming and firing of countermeasures is a key and primary inventive step for any missile defense system. Methods common in the art, such as turrets that rotate via ring gears and motors, or fast linear actuators, are incapable of aiming countermeasures in the timeframes outlined above. Moreover, vehicles and aircraft require defensive coverage throughout a full 360-degrees of azimuth as well as some degree of elevation. Size, weight, systemic, and cost constraints will optimally require this coverage from a single launcher system. Finally, RPG or other types of missile attacks may occur simultaneously, from different directions and/or different elevations. Existing turret-type defensive launcher systems, no matter how fast acting, can not aim at two different targets simultaneously. U.S. Pat. No. 7,190,304 to Carlson, “System for Interception and Defeat of Rocket Propelled Grenades and Method of Use,” describes a combined IR and radar RPG detection system for tactical vehicles and a means for deploying one or more countermeasures, but fails to address the above aiming requirements. Carlson discloses methods of minor course corrections for the countermeasures, but it is not likely that these methods will compensate for large aiming discrepancies. Moreover, steerable countermeasures are much more expensive and complex than countermeasures that are essentially of the point-and-shoot type. Lastly, countermeasures, relying on maneuvering will exclude some types of simple countermeasures that have been demonstrated to be effective against RPGs, such as pellet-type defensive countermeasures. U.S. Pat. No. 7,202,809 to Schade, et al., “Fast Acting Active Protection System” discloses a multi-barrel recoilless gun as the means for aiming and launching countermeasures. Schade, however does not teach how such a gun system is able to physically aim countermeasures in the extremely short timeframe described above. Moreover the system in Schade cannot engage multiple threats simultaneously or nearly simultaneously.
Several complete RPG defense systems have been proposed or are in development. Sometimes referred to as Active Protection Systems (APS), these systems generally use either an explosive kill missile or a 360-degree hail of shot pellets to defeat RPGs. While these systems can be effective, there is serious concern for collateral damage with the use of such systems. Ideally, a defensive system that deploys non-explosive countermeasures to defeat RPG's will greatly reduce the potential for unintended harm to innocent bystanders as well as friendly forces and their assets. Moreover, explosions and hails of pellets are inconsistent with the needs of an RPG defense system that is intended for aircraft deployment. An aircraft-suitable system needs to utilize a carefully-directed countermeasure to avoid damage to itself and other aircraft or dismounted troops in the vicinity. Other deficiencies in existing systems include the inability to engage multiple targets simultaneously and/or in rapid succession, and in some cases the need to reload and service the system after only a single attack. While the technology for detecting RPG attacks appears to be a reality, methods for safely and effectively delivering defensive countermeasures are largely unknown.
There is, therefore, a need for an improved RPG countermeasure delivery system for use in conjunction with available and future detection and warning systems. The system should be capable of delivering non-fratricidal RPG countermeasures, or delivering other countermeasure types in a precisely aimed manner. The system should be adaptable to ground vehicles as well as aircraft, and should be capable of engaging multiple threats simultaneously from different directions and elevations.
SUMMARY OF THE INVENTION
One object of the present invention is to provide an aiming and firing system that covers 360 degrees of azimuth and a substantial elevation coverage while providing very fast aiming throughout this range of coverage.
Another object of the invention is to provide a system that may be deployed in several defensive situations, such as ground vehicles, aircraft, and fixed emplacements.
A further object of the present invention is scalability and the option to adapt the basic platform to various sizes and counter munitions. This is achieved through the simplicity of the mechanical design and the fact that the control scheme is the same regardless of the type of munitions employed.
The present invention provides many advantages over existing munitions launch systems. One advantage is the ability to aim and fire a defensive munitions on a millisecond time scale, thus enabling systems for defense against RPG attack. A further advantage is the ability to deliver multiple individual countermeasures into the pathway of an approaching missile, thus increasing countermeasure effectiveness and defeat probability. This advantage is key to the use of a non-fratricidal flexible-barrier type countermeasure.
Another advantage of the present invention is the ability to provide defensive coverage through 360 degrees while using a single installed unit while maintaining the requisite aiming and firing speed.
Another advantage of the system is the ability to deploy new types of barrier countermeasures such as rocket-towed barriers (RTB's).
Another advantage of the present invention is the ability to deploy existing munitions in a safer manner that reduces fratricidal effects. An example being the deployment of pellet-type (shotgun) RPG countermeasures that are typically fired outward in all directions. Relying on the current system, such counter measures, can be aimed and fired directionally, thus protecting persons and objects not directly in the line with the countermeasure.
Another advantage of the present invention is the ability to defend against simultaneous attack from different directions. The disclosed system can fire countermeasures simultaneously in multiple directions because it effectively has several barrels pointing everywhere at once. A further advantage of such a configuration, is the ability to engage multiple simultaneous attacks occurring at different elevations, such as in the case of simultaneous attack of a ground vehicle from the street level as well as from a rooftop. Such an advantage is accomplished by utilizing a two-tiered rotating array system in which the lower tier is elevated at street level, while the upper tier is elevated to point at the roof.
Yet another advantage of the invention is the ability to defend against multiple attacks without requiring reloading. Assuming a system carrying 16 individual countermeasures, and further assuming that a single RPG attack requires 4 countermeasures to achieve a certainty of defeat; the system is capable of repelling 4 separate attacks before it requires reloading.
Another advantage of the present invention is the option of arming some or all of its launchers or launch tubes with RPG's, thereby providing the capability to deliver return fire. Alternately, other types of weapons, such as guns or cannons may be mounted or interspersed with the countermunitions launch tubes
Other systems, methods, features, and advantages of the invention will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such systems, methods, features, and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is further described in the accompanying drawings. Components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
FIG. 1 is a perspective view of an embodiment the system of the present invention;
FIG. 2 is a perspective view of an alternate embodiment the system of the present invention;
FIG. 3 is a perspective view of a mounting and launcher partial assembly in accordance with an embodiment of the present invention;
FIG. 4 is a perspective view of a launcher tube and elevation adjusting partial assembly in accordance with an embodiment of the present invention;
FIG. 5 is a perspective view of a single rocket-towed countermeasure in stowed condition in accordance with an embodiment of the present invention;
FIG. 6 is a perspective view of a single tow rocket and launch carrier in accordance with an embodiment of the present invention; and
FIG. 7 is an alternative embodiment of the invention that provides for a smaller more compact size.
DETAILED DESCRIPTION
The invention addresses the above need by providing a rapid aiming and launch system that can fire a variety of countermeasures (CMs). In one exemplary embodiment, the system comprises an array of launchers or launch tubes radially affixed to a central hub. Each launcher or launch tube may carry a countermeasure, which can be one of several types. The central hub rotates on a mounting base, allowing any launcher to be directed at any point on a 360 degree azimuth. The system controls rotation via a motor and an encoder tracks the angular position of the launchers. Individual launchers or launch tubes are supported by brackets with a pivot that allows adjustment in elevation. The launchers or launch tubes are ideally connected via a slew ring arrangement to an actuator that controls the elevation of the launchers and is also under system control via linear encoder. The exemplary system may carry more than one array of launchers in a tiered arrangement. All tiers may be affixed to the common rotational hub and rotate together. Alternatively, each tier may rotate at a different rotational speed. Further, each tier is independently adjustable in elevation via its own slew ring and actuator. Slew rings may be arranged centrally in the hub and may be individually connected via concentric tubes. Firing signals to the countermeasures in the launchers or launch tubes may be conveyed to the rotating assembly via slip ring or inductive coupling within the hub.
The exemplary system receives data from a separate threat warning system such as one outlined above. The data would minimally consist of the approach direction (azimuth) and elevation of an approaching threat, such as a RPG or other ballistic projectile. The exemplary system compares the threat approach vector with the angular location of the countermeasure array, and selects the appropriate the individual countermeasure array element (launchers or launch tube) for firing. The angular location of array elements is available via the rotary encoder affixed to the rotating array structure. The exemplary system then rotates the array, via a motor, to bring a CM element onto the desired firing vector and simultaneously adjusts the CM array, via linear actuator, to the correct intercept elevation. The CM is fired and the system may rotate the next CM element into firing position if more countermeasures are required.
An exemplary method consists of operating the system with the hub and radial countermeasure arrays in continuous rotation. In this embodiment, the need to start and stop the rotation during aiming is eliminated, thereby significantly speeding up the process, and allowing for an extremely rapid fire defensive response. Such quick response is a key requirement for defense against close-range RPG attack, where the total time from weapon launch to target contact may be less than one-half second. Because of the limited response window, aiming needs to be almost instantaneous. As will be noted by those skilled in the art, the exemplary method also allows for the simultaneous engagement of multiple attacks from different directions within the same, or differing, time constraints.
Further, in continuous rotation mode the exemplary system receives threat approach data as indicated by one of the systems above. The CM arrays rotates continuously at a known angular rate of speed. The instantaneous angular position of the rotating array elements (launchers or launch tubes) are know to the system via encoder, as is the slew rate (rate of angular travel). Further, the time required for a particular CM to launch and accelerate onto a desired travel vector is also a known parameter of the system. Upon detection and receipt of a threat signal the exemplary system will select the particular array element, i.e., launch tube, that can be brought to fire on the desired intercept heading in the shortest time. This element is the one that is nearest to the correct firing angle, but still having enough angular travel remaining to allow for the short time interval required for all firing system latencies, such as propellant ignition. The embodied system computes the exact firing point, allowing for latencies, such that the CM will depart on the desired intercept heading as the array rotates through that heading. The firing of additional CMs for this intercept heading is simply a matter of repeating the process for CMs behind the first one that was firing.
A typical example will further illustrate the operation and advantages of the invention. In the case of a system employing rocket-towed barrier (RTB) countermeasures, a typical CM array may have 8 countermeasures arranged at 45 degree intervals radially around the plane of revolution. A system may have two or more such arrays arranged in tiers. The non-fratricidal RTB countermeasure is separately described in U.S. patent application Ser. No. 11/030,649 to Glasson, and is incorporated herein by reference. The countermeasure arrays rotate continuously at a fixed speed around their mounting axis. A rotary encoder tracks the angular position of the array, and thus the exact pointing vector of every CM on the array is continuously available to the system's aiming and launch processor. Since there are several equally spaced CMs on the array, the maximum time interval required to bring a CM to bear on any azimuth point is the rotational speed, divided by the number of CMs in the array. If the array rotates at 60 revolutions per minute and there are 8 CMs arranged radially; the maximum aiming latency for any point in the circle would be ⅛ seconds, or 125 milliseconds. This aiming latency is referred to as the segment delay. The embodied system could be optimally configured such that the segment delay for the CM in use is matched to the firing latencies for that particular CM type. This may be done by simply adjusting the rotational velocity (up) to shorten or (down) to lengthen the segment delay. In this way the maximum aiming delay can be calibrated to no more than the time it takes for the countermeasure to fire and leave its stowed position. It will be apparent to those skilled in the art that much faster aim and launch speeds are possible with faster-launching countermeasures.
Utilizing the present invention, countermeasure launch latencies can be reduced through the design of fast-igniting propellant configurations, or explosive ejection charges. The exemplary system can deliver a barrier countermeasure into the path of an oncoming RPG within 125 milliseconds of the launch request, and additional barriers every 125 ms thereafter. Or a fill rate of 8 barrier countermeasures per second into the flight path of an approaching threat. In this mode the elevation adjustment is made as before, via a slew ring bearing connection in the center of each rotating array. The elevation adjustments are accomplished via fast-acting linear actuators, which are common in the art. Exemplary types include a small-bore hydraulic cylinder powered by an accumulator and controlled by servo valves, a lead screw electric actuator suitably configured for fast operation, or optimally, a double-acting solenoid actuator. Since any elevation adjustments will be small, the use of a short range actuator is enabled. This in turn enables the use of simple actuators that are capable of meeting the speed demands of an RPG defense system. Typical double-acting solenoids are capable of 100 Hz actuation rates and have only one moving part.
In the following drawings like numbers are used to depict like elements of the various drawings. FIG. 1 shows an exemplary embodiment of a system in accordance with the present invention. System 100 discloses rotating hub 101 , launchers 102 , and guns 104 . As depicted in FIG. 1 launchers 102 are radially arranged about hub 101 in multiple tiers to provide for 360 degrees of countermeasure protection. While system 100 depicts launchers 102 as tubes, it should be appreciated by those skilled in the art that it is not limited to tubes, and that depending on the preferred countermeasures deployed other configurations are possible. For example, launchers 102 may be open rails, brackets, clamps or other countermeasure housings and holding fixtures without departing from the spirit of the invention. Further, guns 104 are not limited to traditional munitions and may be any type of offensive weapon that a user wishes to deploy in response to a detected threat.
FIG. 2 shows an alternative embodiment of the present invention. System 200 contains rotating hub 101 , launchers 102 , upper support arms 105 and lower support arms 106 . Although not part of the launch system, a typical countermeasure 107 is shown inserted into launchers 102 .
Depending on the specific deployment desired, system 200 may be mounted by rotating hub 101 atop or vehicle, ship or under an aircraft. Additionally, rotating hub 101 provides the mounting means for upper support arms 105 and lower support arms 106 . Upper support arms 105 and lower support arms 106 provide support and a mounting point for launchers 102 . Launchers 102 are pivotally mounted at pivot 117 in the support arms 105 and 106 , providing elevation adjustment with respect to the plane of rotation of rotating hub 101 . In operation, rotating hub 101 provides 360 degree countermeasure coverage, while pivotally mounted launchers 102 provide elevated coverage.
FIGS. 3 and 4 depict a partial assembly of a hub 101 , launchers 102 , and elevation adjusting means as shown. FIG. 3 shows upper support arms 105 and lower support arm 106 fixed to hub 101 and providing support for the two levels of tubes 102 . Upper slot 108 in hub 101 provides an aperture for elevation adjustment arm 119 as shown in FIG. 4 . FIG. 4 depicts the assembly with hub 101 removed for ease of viewing. FIG. 4 depicts an exemplary embodiment of the apparatus for adjusting elevation while allowing rotation of hub 101 and launchers 102 . FIG. 4 discloses tube 102 , plate 110 , link 111 , slew ring 112 , arm 119 , and tube 114 passing through the inner race of bearing 116 and extending through and fixed to the inner race of bearing 113 . Also depicted are slew ring 115 , bearing 116 pressed into the center bore of slew ring 115 , and tube 118 extending through and fixed to the inner race of bearing 116 .
Each tube 102 is closed at the back end by plate 110 . Plate 110 has an arm 119 extending backwards to provide a connection to the elevation adjusting parts. Link 111 connects arm 119 to slew ring 112 , in the upper portion and to slew ring 115 in the lower portion of FIG. 4 .
The slew rings 112 and 115 have different inner diameters to allow for multiple slew rings on a single axis. Each slew ring has a bearing pressed into its center bore. Bearing 113 in the upper slew ring 112 has a smaller inner diameter than bearing 116 , which is pressed into the center bore of slew ring 115 . A larger tube 118 extends through and is fixed to, the inner race of bearing 116 . A smaller tube 114 passes through the inner race of bearing 116 then extends through and is fixed to, the inner race of bearing 113 . The slew rings, bearings, and tubes are preferably located along the axis of hub 101 . Movement of tube, 114 or 118 , with respect to the vertical direction of FIG. 4 , results in pivoting motion of tubes 102 around a pivot 117 in lower support 105 and upper support 106 and provides aiming adjustment of the defensive system.
FIG. 5 depicts an exemplary a rocket-towed barrier countermunition. An exemplary countermunition is shown in the stowed position as it would reside within tube 102 . Tube 102 is removed from FIG. 5 for clarity. The barrier 120 is shown folded and doubled with a tow rocket 121 nested in the center of the barrier. Guide rods 122 provide nesting and uniform stowage to the rocket-towed barrier 120 within tube 102 , and help to guide the barrier out of tube 102 during launch. Plate 110 is provided with a sprue 123 to direct rocket exhaust gases upward.
FIG. 6 depicts an exemplary tow rocket 121 in the stowed position within a launch tube 102 . Tube 102 has been removed for reasons of clarity. Guide rods 125 hold the rocket in a proper orientation and provide guidance as it is launched. Plate 110 is provided with holes 126 to facilitate the mounting of guide rods 125 and 122 . As will be appreciated by those skilled in the art, other munitions and countermeasures, and other mounting and launching configurations, may be utilized without departing from the spirit of the invention.
FIG. 7 discloses an alternative embodiment of the present invention. System 700 contains launch array 701 , containing sixteen launch tubes 702 arranged in two tiers. Each launch tube 702 contains a cap 703 , pellets 704 , wadding 705 , and an explosive charge 706 . An exemplary launch tube 702 is shown away from the assembly.
In this compact embodiment, pellet countermeasures 704 are dispensed in a highly directed way and consecutive shots from multiple launch tubes 702 may be deployed thereby increasing the efficiency of the countermeasure while decreasing the probability of causing collateral damage. In operation system 700 after detecting a threat and determining the proper launcher 702 to respond to the threat, positions the proper launcher 702 , and launches pellets 704 in the general vicinity of the threat by igniting explosive charge 706 behind wadding 705 , thereby causing pellets 704 to launch from the tube 702 in the area of the threat.
While FIG. 7 is depicted with sixteen launch tubes 702 in two tiers, it will be appreciated by those skilled in the art that different numbers of launch tubes and different geometries are possible without departing from the nature of the invention. Further as will also be appreciated, system 700 may be deployed with or without elevation adjustment and may utilize other types of munitions and is not limited to pellet-type countermeasures.
A system and method for rapid aiming and firing of weapons and defensive countermeasures in accordance with the present invention provides defensive coverage for vehicles, ships, and aircraft and mounts a variety of weapons or countermeasures in outwardly-facing arrays. The system rotates continuously and a high speed processor receives data from a threat warning system and selectively fires a weapon or countermeasure in response to an attack.
Those skilled in the art will readily recognize numerous adaptations and modifications which can be made to system and method for rapid aiming and firing of weapons and defensive countermeasures of the present invention which will result in an improved system, yet all of which will fall within the scope and spirit of the present invention as defined in the following claims. Accordingly, the invention is to be limited only by the following claims and their equivalents. | A system and method for rapid aiming and firing of weapons and defensive countermeasures against rocket-propelled grenades or other ballistic devices suitable for use on aircraft, ground vehicles, and ships. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improvement in double-block cumulative multi-draft wire drawing machines.
2. Description of the Prior-Art
In wire drawing machines of the above-mentioned type, the wire is drawn through a succession of stations. Each station includes upper and lower blocks and a spinner carrying a transfer sheave. The blocks and spinner are rotatable relative to each other about a common axis. The lower block is driven to pull wire through a die, with the thus drawn wire then being accumulated temporarily as a plurality of windings on the lower block. The wire then passes from the lower block via the spinner-mounted transfer sheave to the upper block where it is again temporarily accumulated as a plurality of windings before leaving the station to either be passed through a subsequent die or to be finally accumulated on a spool as finished wire.
In order to control the tension of the wire passing between the lower and upper blocks, the spinner is driven, either by an externally contracting drive band which frictionally grips the lower block, or by a motor driving through a V-belt. The direction of rotation of the upper block is either opposite to that of the lower block, or non-existent, depending on whether the blocks are accumulating. The spinner may rotate in either direction, or it may remain motionless.
The rate of wire accumulation on the blocks varies according to the relative drafting practice between stations. While the spinner is motionless, the lower block is passing wire around the transfer sheave and onto the upper block as fast as the wire is coming onto the lower block, and the upper block is passing wire to the next station as fast as it is being received from the lower block. If the succeeding station requires more wire than is being supplied to the lower block, it will pull accumulated wire from the upper block, which in turn will pull accumulated wire from the lower block. However, only one-half the amount required will be pulled from the lower block's accumulation. The other half will be made up from the upper block's accumulation through rotation of the spinner. The wire accumulation is being decreased during this type of operation, with the spinner being rotatably driven in a direction opposite to that of the lower block.
When the succeeding station demands less wire than that being drawn into the lower block, there will be an excess of wire being passed from the lower block to the upper block. In this case, the spinner is rotatably driven in the same direction as that of the lower block, thereby causing one-half of the excess accumulation to go to the lower block and one-half to go to the upper block.
Although this type of machine operates in a generally satisfactory manner, difficulties have been experienced with the manner in which the spinners are driven. For example, the externally contracting drive bands can be adjusted only when the machine is stopped. Thus, tension control of the wire passing from the lower to the upper blocks is largely a matter of trial and error with each adjustment necessitating a machine shutdown. While the V-belt drive offers an improvement in this respect in that it can be adjusted to control tension while the machine is in operation, because the belt is located externally of the blocks, it is exposed to the path of wire movement and is frequently severed when a wire break occurs. Thus, both spinner driving systems are a source of problems.
SUMMARY OF THE PRESENT INVENTION
The present invention has as dual objectives the provision of a spinner drive which can be adjusted while the machine is in operation, and which is not susceptible to being damaged in the event of a wire break.
In a preferred embodiment of the invention to be described hereinafter in more detail, these objectives are achieved by providing means for controllably shifting the spinner axially into and out of frictional contact with the lower block, thereby imparting to the spinner the degree of frictional drive required for a particular operating condition.
Preferably, the spinner is yieldably urged away from the lower block by a separating means which conveniently may comprise a compression spring or other like resilient component, with the control means acting in opposition to the separating means to urge the spinner against the lower block.
Preferably, the control means will comprise an annular piston-cylinder assembly with appropriately arranged thrust bearings.
These and other objectives, features and advantages will be described hereinafter in more detail in connection with the accompanying drawings, wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial perspective view, with portions broken away, of a wire drawing machine embodying the present invention; and
FIG. 2 is a partial cross-sectional and side-elevational view of the upper and lower blocks and spinner at one of the machine stations.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring initially to FIG. 1, a portion of a typical double block cumulative multi-draft wire drawing machine is shown comprising successive stations S 1 , S 2 , and S 3 . Each station operates to pull wire through a respective associated die D 1 , D 2 , and D 3 . For example, and with reference to station S 1 , wire is pulled through die D 1 onto a lower block 10 driven by a drive shaft 12. The shaft 12 carries a worm wheel 14 meshing with a worm gear 16 on a power shaft 18. The power shaft is driven in a conventional manner by a motor and gear box (not shown). The lower blocks of each station are driven through similar sets of worm wheels and worm gears by the same power shaft, with the gear ratios of each set being selected to accommodate the gradually increasing wire speed resulting from the successive drawing operations.
After being drawn through die D 1 the wire is temporarily accumulated as a plurality of windings on the lower driven block 10 before passing via a spinner-mounted transfer sheave 20 onto an upper block 22 where it again is temporarily accumulated as a plurality of windings before leaving the station by passing around another sheave 24 to the next die box D 2 which is associated with the succeeding station S 2 where the operation is again repeated.
Referring now to FIG. 2, it will be seen that the lower block 10 is mounted on the drive shaft 12 for rotation therewith, there being a key or other equivalent connection (not shown) being provided therebetween. A spinner 26 is journalled for rotation on the shaft 12 by means of a pair of roller bearings 28a, 28b. The roller bearings 28a, 28b are axially separated by a sleeve 29 which is free to slide axially along with the inner bearing races on shaft 12. The inner race of the lower roller bearing 28a rests against a flanged collar 30 which is axially movable on the shaft and acted upon by a coiled spring 32 via a thrust bearing 34. The bottom of the spring is seated at the base of a notch 36 in the lower block 10. The spring 32 acts as a separating means for yieldably urging the spinner 26 axially away from the lower block 10 to maintain a spacing therebetween as at 38. The upper face 40 of the lower block 10 carries a replaceable brake shoe 42 which is opposed by a contact face 44 on the underside of the spinner 26. If desired, it would of course be possible to reverse the relative positions of the brake shoe 42 and contact face 44, i.e., to mount the brake shoe on the underside of the spinner and to locate the contact face on the top of the lower drum. The transfer sheave 20 is mounted in a known manner on the spinner 26 for rotation therewith.
The inner hub 45 of the upper block 22 is journalled for rotation on the drive shaft 12 by means of a pair of roller bearings 46a, 46b which are axially separated by a sleeve 48. The inner races of the roller bearings 46a, 46b and the intermediate sleeve 48 also are free to slide axially on the drive shaft. A thrust bearing 50 is interposed between the spinner 26 and a skirt 52 on the inner hub 45 of the upper block 22.
A cylinder head 54 is mounted to the upper end of the drive shaft 12. The cylinder head defines an annular cylinder chamber 56 containing an annular piston 58. A thrust bearing 60 is interposed between the lower end of the piston 58 and the inner hub 45 of the upper block 22. The cylinder chamber 56 communicates via a radial passageway 62 with a circumferential groove 64 in the drive shaft 12. The drive shaft groove 64 in turn communicates via a radial bore 66 with an axial passageway 68. Passageway 68 communicates with a conventional rotary coupling 70 connected to a conduit 72. A suitable control medium, for example compressed air received from a remotely located valve at a central control panel, may be applied via conduit 72, coupling 70, and the communicating passageways 68, 66, 64 and 62 to the cylinder chamber 56, thereby urging the piston 58 downwardly with a force adequate to overcome the opposing force of spring 32. This will result in the upper block 22 and the spinner 26 being shifted downwardly to bring the spinner's face 44 into frictional contact with the brake shoe 42 on the lower drum 10. When this occurs, the spinner will be driven by the lower drum, with the drive force being proportional to the force being exerted by the piston 58. However, the upper drum 22 will continue to rotate freely with respect to the spinner 26 and piston 58 because of the interposition of thrust bearings 50, 60 respectively therebetween.
In light of the foregoing, it will be appreciated that the driving force being imparted to the spinner 26 by the lower drum 10 can be controlled by varying the force being exerted by piston 58. This can be accomplished while the machine is in operation, and from a remote control location. The brake shoe 42, spring 32, piston 58, and other associated components all are positioned at locations which are not exposed to damage in the event of a wire break. Thus, the present invention represents a marked improvement over the arrangements conventionally employed to drive the spinners. | In a wire drawing machine having at least one station with upper and lower blocks and an associated spinner carrying a transfer sheave, the blocks and spinner being rotatable relative to each other about a common axis defined by a drive shaft to which the lower block is drivingly connected, the improvement comprising controllably shifting the spinner axially on the drive shaft into and out of frictional contact with the lower block. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority of U.S. Provisional patent application Serial No. 60/332,076 filed Nov. 21, 2001.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to rotating drilling head systems in which an elastomer seals around and grips a rotating drill pipe during drilling operations.
[0004] 2. Description of the Related Art
[0005] Oil and gas wells are typically drilled by use of a rotating drill pipe with a drill bit at the lower end. Drilling fluids are pumped down the drill pipe and out the drill bit. The drilling fluid returns to the surface, along with cuttings, through the annulus around the drill pipe. In many cases, the pressure at the upper end of the drill pipe annulus is atmospheric. The weight of the drilling fluid is controlled to provide a hydrostatic pressure at the earth formations that is greater than the formation pressure to prevent blowouts.
[0006] In some cases, however, it is advantageous to isolate the pressure at the upper end of the drilling fluid column from atmospheric pressure. For example, in highly deviated well, a lightweight drilling fluid may be used that is not heavy enough to prevent upward flow in the well due to formation pressure. A drilling head at the upper end of the well controls the pressure. Drilling head systems use an elastomeric element to seal the drilling head against the rotating drill pipe during drilling operations. In some rotating drilling head systems, the seal is formed by the natural resiliency of the elastomeric element against the drill pipe while others use hydraulic pressure to deform the seal element. In U.S. Pat. No. 6,016,880, hydraulic pressure to energize an elastomeric gripper element that is located above an elastomeric primary seal. The gripper grips the drill pipe to cause the gripper and primary seal to rotate with the drill pipe. The gripper also serves as a secondary seal in the event of leakage of the primary seal.
[0007] The primary seal of the '880 patent and in other prior art normally comprises an elastomeric seal with a tapered exterior that is exposed to drilling fluid pressure. The drill string has enlarged tool joint sections at the end of each drill pipe that must pass through the interior of the seal. The drilling fluid pressure and movement of the drill pipe through the seal causes extrusion of the seal, which limits the life of the seal.
SUMMARY OF THE INVENTION
[0008] A stripper assembly for sealing around a drill pipe has an annular elastomeric seal member with an inner passage for receiving drill pipe. The seal member has an upper end, a lower end and an outer sidewall. A rigid outer support member extends around and is bonded to an exterior portion of the sidewall of the seal member. An annular rigid lower support member bonded to the lower end of the seal member around the inner passage. The seal member is exposed to drilling fluid pressure, causing a lower portion of the sidewall to deform the seal member inwardly around a drill pipe.
[0009] In the preferred embodiment, the seal member, along with the support members, is mounted inside a cartridge housing. The housing has upper and lower ends an a cylindrical outer wall. The outer wall has at least one hole for admitting drilling fluid. The upper end and lower ends of the seal member engage the upper and lower ends of the cartridge housing. A portion of the outer sidewall of the seal member engages the outer wall of the housing.
[0010] Preferably, the seal member is configured to define a cavity at upper portion of its outer sidewall. The cavity spaces part of the seal member inward from the cartridge housing while not under drilling fluid pressure. The seal member deforms into this cavity while under drilling fluid pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] So that the manner in which the described features, advantages and objects of the invention, as well as others which will become apparent, are attained and can be understood in detail, more particular description of the invention may be had by reference to the embodiments thereof that are illustrated in the drawings, which drawings form a part of this specification. It is to be noted, however, that the appended drawings illustrate only typical preferred embodiments of the invention and are therefore not to be considered limiting of its scope as the invention may admit to other equally effective embodiments.
IN THE DRAWINGS
[0012] [0012]FIG. 1 is an orthogonal view of a rotating drilling stripper constructed in accordance with the present invention.
[0013] [0013]FIG. 2 is a cross section of the rotating drilling stripper of FIG. 1.
[0014] [0014]FIG. 3 is an orthogonal view of the housing of the rotating drilling stripper of FIG. 2.
DETAILED DESCRIPTION
[0015] [0015]FIG. 1 shows a rotating drilling stripper 10 constructed in accordance with the present invention. Stripper 10 is used in drilling operations and is preferably a lower portion of cartridge 12 (partially shown) of a rotating drilling head. Stripper 10 rotates with rotating portion of cartridge 12 , but the present invention would permit a rotational connection between them. In the embodiment of FIG. 1, cartridge 12 and stripper 10 are generally located very near the drilling rig floor. The primary function of stripper 10 is to provide a seal near the upper end of the well annulus through which drilling fluids return.
[0016] The drilling head includes a drilling head housing 13 that is coupled to well casing (not shown) that extends some distance below the surface into the well bore, as well as some distance above the surface, approximately to the drilling rig floor. Cartridge 12 and stripper 10 are inside housing 13 . Housing 13 forms the outer boundary of the well annulus where housing 13 is present. Cartridge 12 has a rotatable inner sleeve 14 and a stationary outer sleeve 17 .
[0017] A gripper element (not shown), such as shown in U.S. Pat. No. 6,016,880, is mounted to inner sleeve 14 above seals 15 and, when supplied with hydraulic fluid pressure, will grip drill pipe 26 to cause inner sleeve 14 and stripper 10 to rotate with drill pipe 26 . Seals 15 seal between inner and outer sleeves 14 , 17 . Lubricant is circulated via passages 19 . Lateral outlet 21 of housing 13 below seal 15 is in fluid communication with the annulus to return the drilling fluid from the annulus to the pump (not shown) for recirculation.
[0018] Stripper 10 mounts to cartridge 12 below seals 15 by conventional means. For example, stripper 10 can be attached to cartridge 12 by passing threaded bolts through a flanged end of cartridge 12 into threaded holes (not shown) in housing 16 of stripper 10 .
[0019] [0019]FIG. 2 shows a stripper 10 having a cartridge housing 16 . Housing 16 must be constructed of very strong material such as steel to withstand large mechanical loads. FIG. 3 shows housing 16 comprises a cylindrical wall 18 and upper and lower ends 20 , 22 , respectively. Ends 20 , 22 each have an axial opening 24 of sufficient diameter to accommodate a drill pipe 26 , including the connecting portion 28 of drill pipe 26 , referred to as tool joints 28 . Cylindrical wall 18 has holes 30 along its lower portion to allow passage of fluids into the lower interior region of housing 16 .
[0020] Stripper 10 further comprises a seal unit 32 , as shown in FIG. 2. Seal unit 32 comprises a rigid upper support or retainer 34 , a seal 36 , and a rigid lower support or retainer 38 . Upper retainer 34 is a structural support element onto which seal 36 is secured, such as by bonding. The upper retainer 34 shown in FIG. 2 generally conforms to the shape of the upper portion of housing 16 . Upper retainer 34 has a cylindrical shell 40 of slightly smaller diameter than wall 18 , and, similar to housing 16 , has an upper end cap 42 with an axial opening 24 to accommodate drill pipe 26 . The portion of end cap 42 nearest drill pipe 26 is slightly thicker than the other portion of end cap 42 , forming a circular support shoulder 44 . Shell 40 extends down along the interior of wall 18 , but stops short of holes 30 . The lowermost end of shell 40 tapers quickly to an edge 46 terminating on the interior of wall 18 above holes 30 . Upper retainer 34 is attached to housing 16 using conventional means such as screws or bolts (not shown). Housing 16 preferably can be conveniently opened and closed to permit access to its interior region, permitting installation or replacement of seal unit 32 . This can be done using various conventional means such as a flange (not shown) connecting end 20 or end 22 to wall 18 , or by placing such a flange in the midsection of wall 18 above holes 30 .
[0021] Seal 36 is preferably made from an essentially incompressible elastomer such as cast urethane or treated natural rubber. Although incompressible, seal 36 is deformable. The embodiment of seal 36 in FIG. 2 is cylindrically symmetric, but has many facets that are most easily described by tracing the cross sectional perimeter of the surface of seal 36 . Beginning at edge 46 of shell 40 and extending upward nearly to end cap 42 , the outermost surface of seal 36 abuts and is bonded to the inner surface of shell 40 . The outer surface of seal 36 stops short of end cap 42 , however, and turns radially inward before continuing upward again until it meets and bonds to end cap 42 . This forms an annular cavity or recessed area 48 having an approximately rectangular cross section bounded by seal 36 , shell 40 , and end cap 42 .
[0022] Continuing along the cross sectional perimeter of seal 36 , the upper end of seal 36 extends radially inward along end cap 42 until it meets shoulder 44 . The upper end of seal 36 extends down and then radially inward to wrap around and conform to shoulder 44 . Where the surface of seal 36 abuts shell 40 , end cap 42 , and shoulder 44 , it adjoins and is held fast by bonding material.
[0023] From shoulder 44 , the surface of seal 36 tapers simultaneously downward and inward to form an upper transition surface 50 . At the inward end of upper transition surface 50 , the surface of seal 36 turns and extends downward nearly the entire length of seal 36 to form a cylindrical sealing surface 52 . Cylindrical sealing surface 52 is slightly smaller in diameter than drill pipe 26 . At the downward end of sealing surface 52 , the surface tapers simultaneously downward and outward to form lower transition surface 54 . Lower transition surface 54 terminates in abutting contact with end 22 of housing 16 . For additional structural support, lower retainer 38 is bonded to seal 36 with bonding material along the lowermost portion of lower transition surface 54 . Lower retainer 38 has an inner diameter greater than the inner diameter of seal 36 and slightly greater than the outer diameter of the connecting joints 28 of drill pipe 26 .
[0024] The remaining portion of the surface of seal 36 extends a very short length outward along end 22 before quickly turning upward and continuing outward until it intersects tip 46 , thus returning to our beginning point. The sloped length of seal 36 from end 22 to tip 46 forms a tapered bearing surface 56 . Bearing surface 56 presents a frustoconical surface to the drilling fluid.
[0025] Stripper 10 effects a seal through a friction fit between sealing surface 52 and the drill pipe 26 that passes through stripper 10 . Energy to maintain the seal is provided by upwardly-directed flowing fluids that enter housing 16 through openings 30 . In conventional drilling, drilling fluids are forced down through the hollow interior of drill pipe 26 to the drill bit and into the well bore, whereupon the fluid, still under pressure, returns to the surface in the annular region between the drill pipe 26 and the well bore.
[0026] While the present invention can be used in such conventional drilling operations, the more modern trend, at least for geologic formations that may be damaged by the pressure exerted by the drilling fluid, is to use underbalanced drilling. Underbalanced drilling relies on overburden pressure to supply the impetus for fluids within the well bore to rise to the surface. Thus, in underbalanced drilling, fluids may rise through the interior of drill pipe 26 as well as the annular region between the drill pipe 26 and the well bore. The present invention is particularly suited for application in underbalanced drilling. In underbalanced drilling, as in conventional drilling, pressurized fluid enters housing 16 through openings 30 .
[0027] Sealing surface 52 is the portion of seal 36 that actually effects the seal against drill pipe 26 in response to the pressure from the drilling fluid impinging on bearing surface 56 . The pressurized fluid that enters into the lower portion of the interior region of housing 16 through holes 30 bears against bearing surface 56 . There is a functional relationship between the pressure bearing on bearing surface 56 and the pressure transferred across sealing surface 52 . The greater the area of bearing surface 56 , the greater the pressure transferred across sealing surface 52 .
[0028] However, one cannot simply maximize the area of bearing surface 56 to produce the maximum sealing pressure on sealing surface 52 . The drill pipe 26 passing through stripper 10 , and particularly a tool joint 28 , tends to tear seal 36 along or adjacent to sealing surface 52 , often at the intersection of sealing surface 52 and upper transition surface 50 . Excess sealing pressure exacerbates the problem because sealing surface 52 tends to deform into the region between the drill pipe 26 and shoulder 44 , or the drill pipe 26 and lower retainer 38 . During those periods in which drill pipe 26 is rapidly removed or inserted (tripping in or tripping out), the frictional force between the drill pipe 26 and sealing surface 52 can cause sealing surface 52 to heat up and weaken. As the tool joint 28 passes by, it tends to lop off the extruded portion, ruining the sealing surface 52 . Transition surfaces 50 , 54 are designed to assist the passage of the drill pipe 26 , particularly the tool joints 28 , by allowing the tool joints 28 to impinge on a tapered surface, giving seal 36 an opportunity to deform out of the path of the drill pipe 26 and tool joints 28 as they pass through stripper 10 .
[0029] Cavity 48 provides a chamber into which seal 36 can deform when pressure is applied to it. By deforming into cavity 48 , seal 36 is less likely to deform into the region between the drill pipe 26 and shoulder 44 , or the drill pipe 26 and lower retainer 38 , and be lopped off or torn by the passing drill pipe 26 or tool joint 28 . Thus, as bearing surface 56 transfers the pressure from the pressurized fluid into seal 36 , seal 36 may change its shape, but its volume is essentially constant and there is no significant energy loss through seal 36 .
[0030] If the expected fluid pressure for a given drilling program is known in advance, such as in an exploitation field, one can select a stripper 10 having a bearing surface 56 just large enough to form an effective seal between sealing surface 52 and the drill pipe 26 . By using just enough pressure to form an effective seal, and no more, the detrimental effects of overpressuring seal 36 are minimized and the life of seal 36 is extended.
[0031] The present invention offers many advantages over the prior art. Placing seal unit 32 inside housing 16 allows for the pre-assembly of strippers having variously sized seals 36 for different drilling environments. It allows for regulating the amount of surface area exposed to the drilling fluid by changing the dimensions of bearing surface 56 . Thus, pressures can be regulated by choosing a seal with a bearing surface 56 optimally sized to accommodate expected drilling pressures. By reducing the pressure applied by the sealing surface 52 onto the drill pipe 26 , the frictional force between them and unwanted extrusion is reduced. That increases the useful lifetime of seal 36 . The useful lifetime of seal 36 is also increased by incorporating a cavity around seal 36 , thereby reducing the likelihood of seal 36 deforming into the region between the drill pipe 26 and shoulder 44 , or the drill pipe 26 and lower retainer 38 , and being lopped off or torn by the passing drill pipe 26 or tool joint 28 .
[0032] While the invention has been particularly shown and described with reference to a preferred and alternative embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. For example, the outer sidewall retainer 34 and upper shoulder 44 need not be connected together. Upper shoulder 44 and lower retainer 38 could be formed in the interior of cartridge housing 16 , and the outer sidewall of seal 36 could be bonded to the interior of housing 16 . However, such would not allow housing 16 to be readily reused with a different seal member. | A stripper assembly for sealing around a drill pipe includes an outer housing having a lateral outlet. The outer housing is mounted at an upper end of a well for receiving an upward flow of drilling fluid and diverting the drilling fluid through the lateral outlet. An inner member is rotatably mounted in the outer housing. A rigid cartridge housing is mounted to the inner member for rotation therewith. The cartridge housing is open to drilling fluid. An annular elastomeric seal member is located in the cartridge housing. The cartridge housing limits upward, downward and outward movement of the seal member as it deforms against the drill pipe due to drilling fluid pressure. | 4 |
CROSS-REFERENCED TO RELATED CASES
This application claims the priority of German patent application Serial No. 199 13 421.9 filed Mar. 25, 1999. The disclosure of the above-referenced German patent application, as well as that of each U.S. and foreign patent and patent application mentioned in the specification of the present application, is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to improvements in methods of and apparatus for transferring rod-shaped commodities which serve to filter tobacco smoke and carry and/or contain pulverulent, granular or otherwise configurated and/or dimensioned ingredients, e.g., particles of charcoal embedded in rod-like fillers of acetate fibers, crepe or the like. More specifically, the invention relates to improvements in methods of and in apparatus for transporting tobacco smoke filtering rods or plugs, which carry confined and/or adherent solid particles, or compel loose particles to advance, along an elongated path from a sender of a file of successive rods to a receiving station.
It is customary to advance a file of successive rod-like filters, normally filters of multiple unit length, along an elongated path which is defined by an elongated pneumatic conveyor in the form of a conduit. If the filters contain and/or carry solid particles, such as granules of charcoal, a certain percentage of solid particles becomes separated from the filters; this results in highly undesirable contamination of the conduit and/or of the parts at the receiving station. Stray particles of charcoal or the like are particularly undesirable at the receiving station because the operation of parts at such station is likely to be adversely affected to a progressively increasing degree unless the apparatus is equipped with suitable means for intercepting stray particles and/or those particles which are likely to become separated from the filters. Attempts to intercept, collect and evacuate solid particles from the path for successive filter rods of a file of such commodities are disclosed, for example, in commonly owned British specification No. 1 410 473 published Oct. 15, 1975 and in U.S. Pat. No. 5,556,236 granted Sep. 17, 1996. The means for admitting granules of charcoal and/or other solid particles can include so-called AC machines (distributed by the assignee of the present application) which sprinkle solid particles onto a running tow of filter material (e.g., acetate fibers).
OBJECTS OF THE INVENTION
An object of the invention is to provide a novel and improved apparatus which can gather and evacuate stray solid particles and/or readily separable solid particles from the path for filter rods for tobacco smoke with a degree of efficiency and reliability exceeding that of heretofore known apparatus.
Another object of the invention is to provide a novel and improved apparatus whose operation is not affected by the rate of delivery of filter rods from a sender to a receiving station.
A further object of the invention is to provide an apparatus which can reliably intercept, gather and dispose of stray solid particles ahead of the station which receives successive filter rods of a file of such commodities and which accommodates devices likely to be adversely affected by stray particles of charcoal or the like.
An additional object of the invention is to provide an apparatus which can intercept and evacuate high percentages of or all solid particles from the path for filter rods of unit or multiple unit length without affecting the quality (such as the configuration) of filter rods.
Still another object of the invention is to provide a novel and improved method of evacuating solid particles (such as granules of charcoal or dust of charcoal and/or other solid additives which enhance the filtering action of the filter rods and/or the flavor of tobacco smoke) from the path for advancement of a series of successive filter rods from a sender (e.g., a filter rod making machine) to a receiving station, e.g., a station which gathers filter rods preparatory to admission into the magazine of a filter tipping machine.
SUMMARY OF THE INVENTION
The invention is embodied in an apparatus for transporting tobacco smoke filtering rods (e.g., filter rod sections of twice, four times or six times unit length), which carry solid particles (such as fragments of charcoal) along an elongated path extending from a sender to a receiving station. The improved apparatus comprises a pneumatic conveyor which defines at least a portion of the elongated path and includes a section provided with openings serving to establish communication between the aforementioned portion of the path and a collecting chamber, and means for propelling (by way of the openings) at least some of the solid particles which become separated from the filtering rods not later than in the aforementioned portion of the path.
The conveyor preferably includes an elongated conduit and the openings can constitute slots provided in the conduit in the aforementioned portion of the path; such slots can extend at least substantially radially of the conduit.
The propelling means can comprise a source of pressurized gaseous fluid (e.g., compressed air) and means for directing gaseous fluid furnished by the source into the conveyor in the regions of the openings.
The conduit of the pneumatic conveyor can include a series of successive annular components which define the aforementioned portion of the path; the openings are then disposed between the successive annular components of the conduit and preferably constitute circumferentially complete slots.
The means for propelling pressurized gaseous fluid from the aforementioned source into the conveyor in the regions of the openings can comprise a pipe or duct receiving pressurized fluid from the source and extending along the aforementioned portion of the path; such duct has outlets (e.g., in the form of orifices or ports) serving to direct jets of pressurized fluid toward at least some of the openings. The duct is preferably closely adjacent to and can serve as a support for the collecting chamber and/or for the aforementioned annular components of the conduit.
The aforementioned portion of the path is or can be at least substantially vertical, and the conveyor is preferably arranged to convey the rods downwardly at least in the at least substantially vertical portion of the path. The particle-collecting chamber of such apparatus is or can be designed and mouted in such a way that it includes an upper portion above and a lower portion below the openings, and an outlet (such as a tubular extension of the lower portion) for collected particles. The chamber can at least partially surround the conveyor in the region of the aforementioned portion of the path.
Another feature of the invention resides in the provision of a method of transporting rod-shaped tobacco smoke filters, which carry solid particles along an elongated path from a sender to a receiving station. The method comprises the steps of directing into a predetermined portion of the path a plurality of jets of a pressurized gaseous fluid to thus expel from such predetermined portion of the path solid particles which are separated and/or separable from the filters, collecting the expelled particles in a chamber which is outwardly adjacent the predetermined portion of the path, and evacuating collected particles from the chamber.
The predetermined portion of the path is or can be at least substantially vertical, and the method can further comprise the step of conveying the filters downwardly into and through the predetermined portion of the path.
The evacuating step can include discharging collected particles from the chamber by gravity flow.
Still further, the method can comprise the step of braking successive filters downstream of the predetermined portion of the path.
The particles can include or constitute fragments of charcoal.
The method can also include the step of establishing a plurality of openings (e.g., in the form of arcuate or annular slots) for the expulsion of solid particles from the predetermined portion of the path into the chamber.
The pressurized fluid is or can be compressed air.
Still further, the method can comprise the step of changing the orientation of filters between the predetermined portion of the path and the receiving station.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved apparatus itself, however, both as to its construction and the modes of assembling and operating the same, together with numerous additional is important and advantageous features and attributes thereof, will be best understood upon perusal of the following detailed description of certain presently preferred specific embodiments with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partly schematic elevational view of an apparatus which embodies one form of the present invention, certain parts at the receiving station being shown in a vertical sectional view; and
FIG. 2 is a greatly enlarged partly sectional view of a section of the pneumatic conveyor, of the particle collecting chamber and of the means for propelling solid particles into the collecting chamber.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring first to FIG. 1, there is shown an apparatus which comprises a sender 1 of a file of successive rod-shaped filters 6 , a pneumatic conveyor including an elongated conduit 2 defining an elongated path for the file of filters 6 , and a receiving station 3 for temporary storage and/or other treatment (such as changing the orientation) of successive filters. The station 3 accommodates or follows a braking or decelerating device 4 which reduces the speed of successive filters 6 being delivered by the conduit 2 , and an accelerating device 7 which follows the braking device 4 and serves to accelerate successive filters 6 ahead of an orientation and direction changing unit including two endless belts or bands 24 (only is one shown in FIG. 1 ).
The apparatus of FIG. 1 can constitute a modified version of the apparatus known as FILTROMAT and distributed by the assignee of the present application. For example, the so-called FILTROMAT 3 can be set up to deliver up to and even in excess of 2500 tobacco smoke filters per minute and can manipulate acetate, crepe, charcoal and dual filters; furthermore, such apparatus are or can be equipped with automatic cleaning means and with a facility for automatic detection and removal of defective rod-shaped filters.
Referring again to FIG. 1, a portion of the elongated path between the braking device 4 and the accelerating device 7 is defined by an elongated arcuate guide 8 having an at least substantially U-shaped cross-sectional outline and an open upper side which is overlapped by a flexible resilient cover 9 of sheet metal or the like. An advantage of such guide is that it can change the direction of movement of successive rod-shaped filters 6 from vertically downwardly (see the upper arrow 16 ) to horizontally (see the lower arrow 16 ) within a small area and without affecting the condition (such as the shape) of successive filters.
The braking unit 4 upstream of the guide 8 comprises upstream pulleys 12 a , 14 a and downstream pulleys 11 a , 13 a , a first endless belt or band 17 a which is trained over the pulleys 11 a , 12 a , and a second endless belt or band 18 a trained over the pulleys 13 a , 14 a. The confronting vertical inner stretches or reaches of the belts 17 a , 18 a engage and decelerate successive filters 6 which are delivered by the pneumatic conveyor including the conduit 2 . The distances between the pulleys 11 a , 13 a and the associated pulleys 12 a , 14 a (i.e., the lengths of the confronting inner reaches of the belts 17 a , 18 a ) are selected in such a way that these belts can reliably engage and decelerate but do not affect the shapes and/or other desirable characteristics of the oncoming filters 6 .
The construction of the accelerating device 7 is analogous to (and can be identical with) that of the braking device 4 , and its parts are denoted by similar reference numerals except that the characters a are replaced with characters b. The difference between the devices 4 and 7 is that the belts or bands 17 b , 18 b of the device 7 serve to accelerate the oncoming filters before such filters reach the endless belts 24 . The means for driving the pulleys 11 a- 14 a at a relatively low speed comprises a prime mover 23 (e.g., an electric motor) and a transmission including a chain or toothed belt 19 a and sprocket wheels or toothed pulleys 21 a , 22 a coaxial with the pulleys 11 a , 13 a , respectively. The means for driving the pulleys is 11 b- 14 b at a relatively high speed comprises the motor 23 (or a discrete second prime mover) and a second transmission including a chain or a toothed belt 19 b and sprocket wheels or toothed pulleys 21 b , 22 b coaxial with the pulleys 11 b , 13 b , respectively. The belts 17 a , 18 a serve to transmit torque from the pulleys 11 a , 13 a to the associated pulleys 12 a , 14 a, and the belts 17 b , 18 b serve to transmit torque from the pulleys 11 b , 13 b to the associated pulleys 12 b , 14 b. As already mentioned above, the belts 17 a , 18 a of the braking device 4 serve to decelerate the filters 6 descending in the conduit 2 , and the belts 17 b , 18 b of the device 7 serve to accelerate the filters arriving from the device 4 along the guide 8 .
The endless belts 24 at the receiving station 3 are trained over pairs of pulleys 26 , 27 (only one of these pairs can be seen in FIG. 1 ). The purpose of the belts 24 is to advance successive oncoming (accelerated) filters 6 sideways (upwardly) into a magazine or reservoir (not shown), e.g., into the magazine of a filter tipping machine (such as a machine known as MAX and distributed by the assignee of the present application) wherein the filters are assembled with plain cigarettes, cigars or cigarillos to form filter-tipped smokers' products. A MAX-type filter tipping machine is described, for example, in commonly owned U.S. Pat. No. 5,135,008 granted Aug. 4, 1992.
The pulleys 27 for the belts 24 are driven by a prime mover (not shown) through the intermediary of a transmission including an endless toothed belt or chain 29 and a toothed pulley or sprocket wheel 28 .
A horizontal guide 31 is provided at the receiving station 3 to steer successive accelerated filters 6 from the device 7 against a wedge-like deflector 32 serving to raise the leaders of successive filters 6 into contact with the confronting reaches of the endless belts 24 so that such belts can move the filters sideways and upwardly into the aforementioned magazine of the filter tipping machine.
In accordance with a feature of the present invention, a section 34 of the conduit 2 upstream of the braking device 4 (i.e., upstream of the receiving station 3 ) cooperates with a unit which serves to propel any loose solid particles 43 (see FIG. 2) which continue to adhere to the external surfaces of the filters 6 and/or which are already separated from the filters into a collecting chamber 33 . The latter can at least partially surround the section 34 and its lower portion has an outlet 42 for evacuation (e.g., by gravity flow) of collected solid particles 43 into a bin or the like, not shown.
The illustrated section 34 of the conduit 2 is a separately produced assembly of vertically aligned annular components 37 which are at least partially separated from is each other by openings 36 in the form of arcuate or circumferentially complete radially extending annular slots 36 . The propelling device which serves to expel loose solid particles 43 from the section 34 of the conduit 2 into the chamber 33 comprises a source 41 of pressurized gaseous fluid (e.g., compressed air), a duct 39 which serves to guide a stream of pressurized fluid upwardly and along the section 34 , and outlets 38 in the form of radial orifices provided in the duct 39 to direct jets of pressurized fluid into and across the section 34 by way of the adjacent openings or slots 36 . This results in the expulsion of loose solid particles 43 from the section 34 and into the collecting chamber 33 . The duct 39 can serve as a carrier for the annular components 37 of the section 34 and/or for the collecting chamber 33 .
The source 41 can include an air compressor or an accumulator (not shown).
The operation of the improved apparatus is as follows:
When the apparatus is in use, the sender 1 supplies a file of successive filters 6 into the conduit 2 wherein the filters advance lengthwise toward the receiving station 3 . During such travel, successive filters 6 advance through the section 34 of the conduit 2 before they enter the braking device 4 . The source 41 supplies pressurized pneumatic fluid into the duct 39 which causes the outlets or orifices 38 to discharge jets of pressurized fluid into the neighboring slots 36 . Such jets expel stray solid particles, as well as those solid particles which are readily separable from the descending filters 6 , from the section 34 of the conduit 2 and into the collecting chamber 33 . The particles 43 which are expelled from the section 34 impinge upon the confronting walls of the chamber 33 and descend toward and into the outlet 42 . The top portion of the chamber 33 is located above the uppermost opening 36 , and the bottom portion of the chamber (together with the outlet 42 ) is located beneath the lowermost opening 36 of the illustrated section 34 .
The filters 6 which descend beyond the section 34 of the conduit 2 are force-lockingly engaged and decelerated by the belts 17 a , 18 a of the braking device 4 . Such filters are devoid of loosely adhering solid particles 43 . Braking of the filters 6 by the device 4 results in the accumulation of a column of superimposed filters above the belts 17 a , 18 a. Such column rests upon and exerts a considerable downwardly oriented force upon the filter 6 which happens to be engaged and braked by the belts 17 a , 18 a . However, and since the lengths of the confronting inner reaches of the belts 17 a , 18 a are selected with a view to force-lockingly engage at least a major portion of a filter 6 advancing through the braking device 4 and actually supporting a column of superimposed filters, such filter can be properly decelerated by the belts 17 a , 18 a without undergoing any, or any appreciable, deformation.
It is often sufficient to utilize a braking device wherein the length of the confronting inner reaches of the belts 17 a , 18 a is less (even considerably less) than or exceeds the length of a filter, depending for example upon the length and weight of the filters supplied by the sender 1 .
Successive filters 6 which advance downwardly beyond the braking device 4 enter and slide along the arcuate guide 8 on their way toward and into the accelerating device 7 . The confronting inner reaches of the belts 17 b , 18 b engage and accelerate successive filters 6 in a direction toward the deflector 32 . Such acceleration ensures that the filters 6 advancing along the guide 31 are out of contact with the neighboring (preceding and next-following) filters so that a filter which is deflected at 32 is not interfered with by the next-following filter. The belts 24 transport successive filters 6 sideways and upwardly into the aforementioned magazine or to any other selected destination.
An important advantage of the improved method and apparatus is that the structure which is shown in FIG. 2 (or an equivalent thereof) is capable of relieving the interior of the section 34 of the conduit 2 and the filters 6 advancing toward the braking device 4 of loose solid particles 43 when the filters descend into the section 34 at a relatively low or at a higher or much higher speed. This greatly reduces the likelihood of undesirable stoppages for the purpose of cleaning the braking device 4 , the guide 8 and/or the accelerating device 7 .
Another advantage of the improved method and apparatus is that the interior of the collecting chamber 33 need not be maintained at an elevated pressure because the particles 43 which are in the process of entering or have already entered this chamber can be evacuated automatically, i.e., by gravity feed.
A further advantage of the improved method and apparatus is that the expulsion of solid particles from the path leading from the sender 1 to the receiving station 3 can be effected in a surprisingly short portion (section 34 ) of the conduit 2 .
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic and specific aspects of the above outlined contribution to the art of transporting filter rods and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the appended claims. | Apparatus for transporting rod-shaped tobacco smoke filters, which contain and/or carry particles of charcoal and/or other particulate tobacco smoke filtering and/or flavoring material, wherein a sender directs a series of successive filters lengthwise into a pneumatic conduit extending toward or into a receiving station. A section of the conduit ahead of the receiving station is provided with openings communicating with a collecting chamber. A duct which extends along the section of the conduit is provided with orifices serving to direct jets of a pressurized gaseous fluid into the openings to thus expel loose particles and/or particles adhering to the external surfaces of filters into the collecting chamber. The latter discharges collected particles by gravity flow. | 0 |
FIELD OF THE INVENTION
This invention relates to a chair arranged to support a person thereon such that the person may be inverted for therapeutic purposes.
BACKGROUND
Inversion devices such as inversion chairs and tables are known for therapeutic purposes and particularly for the treatment of a person's spine to relieve pain and tension from the spine by inverting the person supported thereon. These devices generally comprise a frame and a support pivotally mounted on the frame such that a person may be supported thereon for pivotal movement between an upright position and an inverted position. The devices generally require a person to pivot themselves in a rearward direction from the upright position to the inverted position such that the person faces upward as they are pivoted. This often results in a situation where the person is pivoted in an uncontrolled manner which may result in injury as there is no fixed support structure within reach of the person as they are pivoted. This rearward rotation can also cause significant disorientation.
One inversion device known as the Bac-Trac, provides a frame which supports a lap pad above the ground for pivotal movement about a horizontal axis. In use, a person stands adjacent the frame such that the lap pad extends laterally across their waist. The person then pivots themselves forwardly with the pad about the horizontal axis while being supported entirely by the unstable mounted lap pad. A laterally extending safety bar is arranged to extend across the back of the person's knees once the person has inverted themselves about the horizontal axis. The lap pad however, is arranged to pivot freely in either direction and requires significant strength and control on the part of the user to guide themselves through the inversion as the device provides no support to the person other than across the waist and across the back of the knees. This type of inversion is unsuitable for persons who are not already considerably fit.
SUMMARY
According to one aspect of the present invention there is provided an inversion chair for inverting a person supported thereon, the chair comprising:
a frame;
a seat pivotally mounted on the frame for pivotal movement between an upright position and an inverted position in which the seat is substantially inverted relative to the upright position, the seat being arranged to support the person thereon;
a restraint coupled to the seat and being arranged to restrain the person within the seat as the seat is pivotally displaced from the upright position to the inverted position; and
a stop member restricting rearward pivotal rotation of the seat from the upright position to the inverted position;
whereby the seat rotates forwardly and faces downwardly as the seat is displaced from the upright position to the inverted position.
The inversion chair allows a person to be inverted from the upright position to the inverted position by pivoting the chair in a forward direction. By pivoting the chair forwardly, a fixed supporting structure such as the frame of the chair or the ground beneath the chair is within reach of the person in the chair during the entire movement between the upright and inverted positions. This allows the movement to be executed in a controlled manner for reducing possible risk of injury as a result of the chair tipping in an uncontrollable manner. Furthermore, forward rotation is a more natural movement that rearward rotation, resulting in less mental resistance to the inversion process and thus better relaxation is achieved for optimal results for both disabled and able bodied users.
There may be provided a locking member mounted on the frame arranged to engage the stop member, the locking member being selectively separable from the frame to permit displacement of the seat in both forward and rearward directions in relation to the frame when the locking member is removed.
Preferably there is provided various mounting locations for the locking member each corresponding to a relative orientation of the seat in relation to the frame.
For use as a rocking therapy, there may be provided a rearward locking member mounted on the frame arranged to engage the stop member in a reclined position in which the seat extends at a rearward incline in relation to the upright position and a forward locking member mounted on the frame arranged to engage the stop member in a forward inclined position in which the seat extends at a forward incline in relation to the upright position. The seat is thus arranged to pivot freely between the reclined position and the forward inclined position. Rocking therapy involves rocking forward and back to relieve the constant pressure on the spine.
To be used for drafting and the like, there may be provided a forward locking member mounted on the frame arrange to engage the stop member in a forward inclined position in which the seat extends at a forward incline in relation to the upright position, the locking member being arranged to restrict displacement of the seat in relation to the frame. A person may then be supported on the chair at a forward incline in relation to a substantially level table top. Additional restraints may be used for securing the legs and upper torso of the person in the chair when the seat is inclined forwardly when drafting and the like.
For use as an inversion chair, there may be provided an upper locking member mounted on the frame arranged to engage the stop member in the upright position for restricting rearward pivotal movement of the seat in the upright position and a lower locking member mounted on the frame arranged to engage the stop member in the inverted position for restricting rearward pivotal movement of the seat in the inverted position.
The frame preferably includes a lift mechanism arranged to raise the seat in the inverted position.
When the frame comprises a plurality of legs supporting the seat thereon, the lift mechanism preferably comprises an actuator associated with each leg for selectively extending a length of the leg to raise the seat. Alternatively, the pivot supporting the seat on the frame may be adjustable in relation to the ground by mounting the seat pivot on a track or the like which is supported on the frame. The seat may then be displaced vertically in relation to the frame which supports the seat above the ground.
A damper may be mounted between the seat and the frame for providing limited resistance to the relative pivotal movement therebetween.
The damper may comprise a pair of bushings pivotally supporting the seat on the frame. Suitable materials for the bushing include metal and carbon materials. Other forms of dampers may include fluid displacement type dampers and the like. A cam lock may also be provided for selecting the desired amount of resistance to pivotal movement. A damper would not be required in an automatically operated embodiment.
When using a damper in a manually operated embodiment, the seat is also preferably biased towards the upright position by a spring or other similar mechanism.
There may be provided a locking member arranged to secure the seat in the upright position.
The restraint preferably comprises a laterally extending support arranged to be secured across a lap of a person supported in the seat wherein the support includes an adjustable mounting mechanism arranged to mount the support at various spacings in relation to the seat.
A drive mechanism is preferably coupled between the seat and the frame controlling pivotal movement of the seat in relation to the frame. The drive mechanism preferably includes controls mounted on the seat which are arranged to be accessible to a person supported in the seat through a full range of motion of the seat in relation to the frame. The drive mechanism allows complete control of the inversion process by disabled persons without assistance or supervision being required. The drive mechanism preferably further includes an integral stop mechanism providing limits to the amount of rotation permitted and the direction of rotation permitted depending upon the angular position of the seat in relation to the frame.
The drive mechanism may include a seat lift mechanism arranged to raise the seat in the inverted position in relation to the upright position automatically as the seat is displaced between the upright position and the inverted position by the drive mechanism.
According to a further aspect of the present invention there is provided a method of inverting a person comprising;
providing a chair which is supported for pivotal movement about a substantially horizontal chair axis;
sitting the person on the chair to face in a forward direction;
restraining the person to the chair; and
pivoting the chair about the chair axis in the forward direction from an upright position to an inverted position in which the chair is inverted about the chair axis in relation to the upright position such that the person faces downwardly as the chair is pivoted.
The method preferably includes restricting pivotal movement of the chair in a rearward direction when the chair is in the upright position.
A damper on the chair may be used to partially resist pivotal movement of the chair.
Pivotal movement of the chair is preferably biased towards the upright position.
The method may further include lifting the chair before it is pivoted into the inverted position.
Locking the chair in the inverted position may be desirable for ensuring the person in the chair is supported in a stable manner in the inverted position.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, which illustrate exemplary embodiments of the present invention:
FIG. 1 is a side elevational view of the chair in an upright seated position;
FIG. 2 is a side elevational view of the chair in an inverted position;
FIG. 3 is a partly sectional front elevational view of the chair;
FIG. 4 is a top plan view of a lap bar for use with the chair;
FIG. 5 is a sectional view of a pivot mount which supports the chair;
FIG. 6 is a side elevational view of the chair in a reclined position;
FIG. 7 is a side elevational view of the chair in a forward inclined position;
FIG. 8 is an isometric view of an alternative chair and lap pad design; and
FIG. 9 is a partly section side elevational view of an automated embodiment of the chair.
DETAILED DESCRIPTION
Referring to the accompanying drawings, there is illustrated an inversion chair generally indicated by reference numeral 10 . The inversion chair is arranged to support a person 12 thereon such that the person may be inverted for purposes of treating the spine of the person.
The chair 10 includes a frame 14 having a pair of upright and spaced apart sides 16 . Each side 16 includes a pair of leg members 18 which are mounted, spaced apart in a generally upright orientation. The leg members are connected at a top end by an upper crossbar 20 which extends at a forward and downward incline between the respective top ends of the leg members. A lower crossbar 22 mounts between each pair of leg members 18 at a location spaced below the corresponding upper crossbar 20 . The sides 16 formed from steel angles which have been bent, welded and appropriately finished.
The leg members 18 each comprise an extendable actuator. This may include an air driven piston cylinder or a hydraulic piston cylinder arrangement, either of which are arranged to be selectively extended for raising the chair as desired.
Each side 16 of the frame 14 includes frame panel 28 which is mounted between the upper and lower crossbars. Each frame panel 28 is arranged to mount a pivot mount 30 on an inner face thereof. The pivot mounts 30 are arranged to pivot about a horizontal chair axis 32 extending between the pivot mounts.
A seat 34 is mounted on the pivot mounts 30 for pivotal movement about the chair axis 32 relative to the frame 14 . The seat 34 includes a seat bottom 36 which is supported on a pair of seat supports 38 which are mounted adjacent a bottom face of the seat bottom. The seat supports 38 are parallel and spaced apart and mount a pair of back supports 40 on a rearward end thereof to extend generally upward therefrom. The back supports 40 are parallel and spaced apart members which support a seat back 42 thereon. A pair of arm supports 44 are mounted on the respective back supports 40 spaced upwardly from the seat supports 38 to extend generally forward from the back supports. The arm supports 44 are connected at a forward end to the respective forward ends of the seat supports 38 by a pair of front supports extending therebetween.
A pair of seat panels 48 are mounted on the respective sides of the seat 34 . Each seat panel 48 , extends between a corresponding arm support 44 and a corresponding seat support 38 . The seat panels 38 are perforated panels which are arranged to couple to the respective pivot mounts 30 for pivotally supporting the seat 34 on the frame. At least one of the seat panels 48 is removable with the use of fasteners such that the seat may easily be installed on the frame 14 upon assembly of the chair.
In a stationary upright position, the seat bottom 36 is arranged to extend at an upward angle at approximately 5 degrees from a rearward end to a forward end. The seat bottom is covered with a layer of fabric bonded to dense foamed neoprene which in turn is bonded to moulded 25 millimeter thick hardwood plywood.
In the upright position the seat back 42 is arranged to extend at an upward and rearward incline of approximately 78.5 degrees from horizontal. The seat back is also covered in fabric which is contoured over a 15 millimeter layer of soft foam bonded to a 19 millimeter layer of contoured hardwood plywood. A lower portion 50 of the seat back 42 is arranged to curve inwardly towards the person for providing additional support to the lower back. An upper portion 52 of the seat back is arranged to curve rearwardly and then forwardly adjacent the top end for supporting the shoulders and neck of a person in the chair.
A lap restraint 54 , is mounted between respective sides of the seat for supporting the person in the seat in an inverted position in which the seat is inverted in relation to the upright position about the chair axis. The lap restraint includes a pair of upper lap bars 56 secured adjacent a bottom face of respective arm supports 44 . A lower lap bar 58 is mounted spaced below each upper lap bar 56 by a respective lap panel 60 . The upper and lower lap bars are connected at a forward end on the respective front supports of the seat, The upper and lower lap bars are connected at a rearward end by a respective rear lap bar 62 , the supports and bars forming the seat 34 and the lap restraint 54 are formed from steel angles similarly to the frame 14 .
A lap pad 64 is provided for coupling between the lap panels 60 . The lap panels are perforated with numerous vertically and horizontally spaced apart mounting apertures for adjustably mounting the lap pad thereon. The lap pad 64 comprises a generally rectangular 25 millimeter thick hardwood plywood. A set of 4 barrel bolts 66 are mounted adjacent respective corners of the lap pad to extend laterally outward from respective sides 68 of the pad. The barrel bolts 66 are arranged to be received in corresponding mounting apertures in the respective lap panels.
A top side of the lap pad 64 is finished with a 6 millimeter particle board layer covered with a plastic laminant. A bottom side of the lap pad is covered by a 25 millimeter layer of dense upholstery foam followed by a 25 millimeter layer of medium dense upholstery foam. A cloth cover covers the two foams while a perimeter vinyl T conceals the edge of the plywood.
The leg members 18 are finished with an easily gripping surface to further provide control to the person as the person pivots themselves from the upright position to the inverted position.
The chair and chair axis are arranged such that both the center of mass of the chair and the center of mass of a person sitting in the chair are adjacent the chair axis. In this arrangement, the chair and the person remain balanced about the chair axis as the person is inverted with the chair about the chair axis. This provides minimal resistance to the rotation of the chair for optimal control of the rotation by the person in the chair with little effort required on the part of the person for further reducing risk of injury.
Each pivot mount 30 includes an axle 80 supported on the corresponding frame panel and a housing 82 mounted on the seat. The housing 82 is rotatably supported on the axle 80 and includes a bushing 84 which supports the housing on the axle. The bushing 84 acts as a damper to partially resist rotation of the seat in relation to the frame. A spring 86 is mounted between the axle 80 on the frame and the housing 82 on the seat. The spring 86 is arranged to bias the seat towards the upright position to assist a person in the inverted position in returning to a normal upright and seated position.
A stop 88 is mounted on the housing 82 for pivotal movement with the seat about the chair axis. The stop 88 includes an aperture therein arranged to receive a locking member 92 therethrough for securing the relative orientation of the seat to the frame. The locking member is arranged to be selectively separable from the frame to permit the seat to be secured at any one of numerous relative positions.
The frame panel 28 on each side includes a plurality of locking apertures spaced circumferentially about the chair axis for receiving one or plural locking members therethrough. The locking apertures 90 are in alignment with the aperture in the stop 88 so as to permit the locking member 92 to be inserted therethrough. Insertion of the locking member into one of the locking apertures 90 without inserting the locking member into the aperture in the corresponding stop 88 arranges the locking member to engage the stop 88 for limiting relative pivotal movement in one direction only.
In this arrangement the chair may be used as a seat shown in FIG. 1, as an inversion chair as shown in FIG. 2, as rocking chair as shown in FIG. 6 or in a working position as illustrated in FIG. 7 . In the seated position of FIG. 1 the locking member 92 is received through the aperture in the stop 88 and one of the locking apertures 90 corresponding to the seat and the person therein being generally upright.
When used as an inversion chair, upper and lower locking members 94 and 96 are inserted through respective locking apertures 90 which correspond to the end of travel of the seat when engaged with the stop 88 in the respective upright and inverted positions.
Similarly when used as a rocking chair, forward and rearward locking members 98 and 100 are mounted in respective locking apertures 90 to engage the stop 88 defining the end of travel of the seat's pivotal movement between a reclined position shown in FIG. 6 and a forward inclined position similar to that of FIG. 7 . Further to the use as a rocking chair insertion of either of the forward or rearward locking members 98 and 100 through the corresponding aperture in the stop 88 on the pivot mount may selectively lock the seat in either one of the respective reclined or forward inclined positions. As illustrated in FIG. 7 the forward inclined position is particularly useful when working at a drafting table for example.
The chair as illustrated in the accompanying drawings is suitable for inverting a person supported thereon in a safe and controllable manner. A person first sits in the seat facing in a forward direction as illustrated in FIG. 1 and is restrained in the chair by the lap restraint illustrated in FIG. 4 . The upper lock member 94 ensures that the seat is restricted from pivoting rearward and thus the person is inverted by pivoting the seat forwardly about the chair axis in the forward direction so as to face downwardly as the chair is pivoted. The damper and spring member on the pivot mount assist in pivoting the seat in a controlled manner.
Before pivoting the chair into the inverted position the leg members 18 are preferably extended as illustrated in FIG. 2 in relation to FIG. 1 . The arrangement of the extendable leg members provides that the seat is at a suitable sitting height when used in the seated position of FIG. 1 while providing sufficient head room when extended and the chair is pivoted into the inverted position of FIG. 2 . It may be desirable to use the lower locking member 96 inserted through the aperture in the stop 88 to lock the seat in the inverted position of FIG. 2 .
The forward rotation of the seat from the upright position to the inverted position ensures that a fixed supporting structure either in the form of the frame of the chair or the ground is always within reach of the person using the chair. For example a person may first shuffle their feet along the ground to pivot the chair in a forward direction until the leg members 18 are within grasp. At this point the person may grab the leg members using their hands for further controlling the pivotal movement of the seat as their feet are raised from the ground. The person continues to urge the chair to pivot forward from the upright position until the chair is completely inverted at which point the person may easily reach out over their heads and touch the ground below them as illustrated in FIG. 2 to control the pivotal movement of the seat in relation to the frame.
An alternative seat 100 and lap restraint 102 is illustrated in FIG. 8 . The seat 100 is arranged to be supported by respective pivot mounts 104 on opposing sides of the chair for pivotal movement on a frame (not shown) similarly to the previous embodiment. The lap restraint 102 includes a tubular member 106 mounted to extend perpendicularly upward from each side of the bottom 108 of the seat 100 . A lap pad 110 is arranged to extend laterally across a lap of a person supported in the seat 100 for mounting between the tubular members 106 .
A mounting bar 112 extends laterally across a top side of the lap pad 110 and includes respective mounting portions 114 extending downward from each end of the mounting bar 112 at a respective end of the lap pad 110 . The mounting portions 112 are arranged to be slidably received within the respective tubular members 106 on each side of the seat 100 .
A spring loaded protrusion 116 on each mounting portion 112 is arranged to be depressed as the corresponding mounting portion is inserted within its respective tubular member 106 and then subsequently is deflected to project outwardly through one of numerous co-operating mounting apertures 118 in the tubular member 106 to secure the lap pad in place. The mounting apertures 118 are mounted at various vertical spacings along the respective tubular members 106 such that the lap pad may be mounted at any one of numerous heights in relation to the seat 100 by selecting which pair of co-operating mounting apertures 118 are arranged to receive the respective pair of protrusions 116 therethrough in a mounted position. Depressing the protrusions 116 release them from the respective apertures 118 for removal of the lap pad or to adjust the height of the lap pad.
An automatically operated embodiment is illustrated in FIG. 9 wherein there is provided chair 130 having a seat 132 pivotally supported on a frame 134 as in previous embodiments. The chair 130 includes a drive mechanism 136 coupled between the seat 132 and the frame 134 controlling pivotal movement of the seat in relation to the frame.
The drive mechanism 136 is enclosed within a housing built integrally with the frame 134 of the chair and includes an electric drive motor 138 . The motor 138 includes drive gear 140 which is arranged to drive the rotation of a driven gear 142 coupled to rotate with the seat 132 . Upon activation of the motor, the drive gear 140 rotates the driven gear 142 and the seat 132 together between the respective upright and inverted positions.
The drive mechanism 136 includes respective up and down controls 144 mounted on an arm rest 146 of the seat which is arranged to be inverted with the seat. The controls 144 are thus arranged to be accessible to a person supported in the seat through a full range of motion of the seat in relation to the frame. The controls include a forward actuation button 148 and a rearward actuation button 150 for selectively controlling forward and rearward pivotal movement of the seat in relation to the frame when the respective button is depressed for the duration of the rotation desired. Releasing either button 148 or 150 will stop the motor and thus brake the pivotal movement of the seat so that the seat may be stopped at any one of various position between the upright and inverted positions.
The drive mechanism further includes various modes of operation including rocking therapy in which the seat is automatically driven between the forward and rearward inclined positions and inversion in which the seat is automatically inverted forwardly in relation to the upright position a predetermined degree of rotation wherein the seat is restricted from further rotation by an integral stop mechanism which is adjustable to a range of desired angular rotations.
The drive mechanism also includes a seat lift mechanism in the form of actuators 152 on each leg of the frame 134 as described in the first embodiment. Upon activation of the drive mechanism to invert the seat 132 , the controls 144 are arranged to raise the seat in the inverted position in relation to the upright position automatically as the seat is displaced between the upright position and the inverted position by the drive mechanism. The chair is thus arranged to support the seat at a normal sitting height for use as a conventional chair while providing sufficient head room when used for inversion.
While various embodiments of the present invention have been described in the foregoing, it is to be understood that other embodiments are possible within the scope of the invention. The invention is to be considered limited solely by the scope of the appended claims. | A method and apparatus is provided for inverting a person for various therapeutic purposes. The apparatus comprises a chair which is pivotally supported about a horizontal axis between various positions having different relative inclinations. When used for inversion, a stop is mounted on the chair to restrict rearward pivotal movement of the person from an upright position to an inverted position. The method thus includes pivoting the person forwardly from the upright position to the inverted position in which the person is substantially inverted in relation to the upright position. The chair may further include a damper and a biasing device for dampering the pivotal displacement of the chair and biasing the chair to the upright position. A lift mechanism may further be used for raising the chair in the inverted position. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part (CIP) of U.S. patent application Ser. No. 14/509,990, filed Oct. 8, 2014, which claims the priority of U.S. Provisional Patent Application No. 61/888,162, filed Oct. 8, 2013, the disclosures of which are incorporated herein by reference and to which priority is claimed.
FIELD OF THE INVENTION
The invention generally relates to the fields of civil engineering, hydraulic engineering, and soil and water conservation. More specifically, the invention relates to a manufactured device to prevent scour around hydraulic structures.
BACKGROUND
Removal of river bed substrate around bridge pier and abutment footings, also known as scour, presents a significant cost and risk in the maintenance of many bridges throughout the world. Bridge scour at the foundations of bridge piers and abutments is one of the most common causes of highway bridge failures. It has been estimated that 60% of all bridge failures result from scour and other hydraulic-related causes (Hunt, 2009). In 1973, a study by the US Federal Highway Administration (FHWA) was conducted to investigate 383 bridge failures caused by catastrophic floods, and it concluded that 25 percent involved pier damage and 72 percent involved abutment damage (Richardson and Davies, 2001). This has motivated research on the causes of scour at bridge piers and abutments (Ettema et al., 2004) and led bridge engineers to develop numerous countermeasures that attempt to reduce the risk of catastrophe. Unfortunately, all such countermeasures currently in existence and practice are temporary responses that cannot endure throughout the lifetime of the bridge and do not prevent the formation of scouring vortices, which are the root cause of local scour. Consequently, sediment such as sand and rocks from around the foundations of bridge abutments and piers is loosened and carried away by the flow during floods, which may compromise the integrity of the structure. When these temporary scour countermeasures are used for at-risk bridges, expensive monitoring technologies and support professionals are required to enable sufficient time for implementing contingency plans when failure is likely. Even designing bridge piers or abutments with the expectation of some scour is highly uncertain, since a study (Sheppard et al., 2011) showed huge uncertainties in scour data from hundreds of experiments. Other than the innovation of Simpson et al. (U.S. Pat. No. 8,348,553), none of the conservative current bridge pier and abutment footing or foundation designs prevents scouring vortices, so the probability of scour during high water or floods is present in all of those designs.
The bridge foundations in a water current (WC), such as piers (P) and abutments (A), change the local hydraulics drastically because of the generation of large-scale unsteadiness and shedding of coherent vortices, such as horseshoe vortices, by the piers and abutments. FIG. 1 is a sketch of the horseshoe vortex (HV) formed around the base of a bridge pier (P) hydraulic structure by a separating boundary layer. The horseshoe vortex (HV) has high lift and shear stress and triggers the onset of sediment scour and a scour hole (SH) is formed as shown in FIG. 1 .
The flow field around a vertical-wall abutment (A) is highly three-dimensional and involves strong separated vortex flow around the abutment as shown in FIG. 2 . A separation bubble (SB) is formed at the upstream corner of the abutment. Unsteady shed wake vortices (WV) are created due to the separation of the flow at the abutment corners. These wake vortices (WV) are very unsteady, are oriented approximately vertical and have low pressure at the vortex cores. These vortices act like small tornadoes, lifting up sediment from the sediment bed (SB) and creating a large scour hole (SH) behind the abutment (A) and a downstream scour hole (DSH). The down flow (DF) at the front of the abutment is produced by the large vertical stagnation pressure gradient of the approaching flow. The down flow rolls up and forms the primary vortex (PV) as shown in FIG. 2 , which is similar to the formation of the horseshoe vortex around a single bridge pier. FIGS. 3 and 4 show the flowfield (FF) past a wing-wall abutment (A) and spill-through abutment (A), respectively, where deep contraction scour can occur due to vortices, high turbulence (HT), and flow separation zones (FS).
Bridge scour is comprised of three components: long-term aggradations and degradation of the river bed, general scour at the bridge, and local scour at the piers or abutments (Lagasse et al. 2001). The structural countermeasures are used primarily to minimize local scour, such as extended footings, scour collars, pier shape modifications, debris deflectors, and sacrificial piles, all of which are only marginally effective. A number of collar devices (Titman, U.S. Pat. No. 3,529,427; de Werk, U.S. Pat. No. 4,279,545; Larsen, U.S. Pat. No. 3,830,066; Larsen, U.S. Pat. No. 3,844,123; and Pedersen, U.S. Pat. No. 3,859,803) encircle the lower end of hydraulic structures, but do not prevent scour on the downstream side of the structure. A similar anti-scour apparatus comprising an upper and a lower collar was patented by Loer (U.S. Pat. No. 4,717,286). Larsen (U.S. Pat. No. 4,114,394) describes the use of a sheet or sack housing film material, which is secured around a hydraulic structure with cables. All of the above collar devices would only have a local effect and local scour will still happen around the vicinity of the collar, as shown by Tian et al. (2010) in work performed in the flume at Applied University Research (AUR). In U.S. Pat. No. 5,839,853 (Oppenheimer and Saunders), one structure of vortex generators, located upstream of the hydraulic structure, is specified to produce a pair of stream-wise vortices that move toward the free surface and protect the hydraulic structure from the impact of oncoming debris. Another structure of vortex generators is positioned directly in front of the hydraulic structure to prevent the streambed from scouring by counteracting the horseshoe vortex (also sometimes called the necklace vortex) formed by separation at the hydraulic structure nose if there was no control. Simpson (2001) showed that this counteracting mechanism fails as a scour countermeasure.
For abutments, Barkdoll et al. (2007) reviewed the selection and design of existing bridge abutment countermeasures for older bridges, such as parallel walls, spur dikes located locally to the abutment, and horizontal collar-type plates attached to the abutment. Two similar collar devices (Lee et al., U.S. patent Ser. No. 10/493,100; Mountain, U.S. patent Ser. No. 11/664,991) are comprised of a number of interlocking blocks or bags in a monolayer or multilayer on the stream bed around abutments. However, these horizontal collar type scour countermeasures are only marginally effective as shown in the flume test results of Tian et al. (2010). The scour hole at the upstream abutment corner is eliminated, but the downstream scour hole due to the wake vortex shedding becomes more severe. In another approach to prevent streambed scour of a moving body of water, a scour platform is constructed by placing an excavation adjacent to the body of water (Barrett & Ruckman, U.S. Pat. No. 6,890,127). The excavation is covered with stabilizing sheet material, filled with aggregate, and extends up or downstream a desired length. However, the local scour around the excavation is inevitable, especially when the excavation is exposed to a moving body of water.
With the above prior art, Simpson et al. (U.S. Pat. No. 8,348,553) proved through model-scale and full-scale tests and disclosed a manufactured three-dimensional convex-concave fairing with attached vortex generators, for hydraulic structures such as bridge piers and abutments, whose shape prevents the local scour problem around such hydraulic structures even when the inflow is at an angle of attack to the hydraulic structure ( FIGS. 5 and 6 ). The Simpson et al. device is effective at preventing vortices that cause substrate transport for a large range of river flow conditions and bed substrate materials because it fundamentally alters the way the river flows around the pier.
FIG. 5 shows flow around the Simpson et al. device streamlined bridge pier fairing that remains attached without the formation of vortices. The convex-concave pier fairing nose (CCPFN) is located below the faired pier nose (FPN) and prevents the formation of vortices, as does the faired side (FS). The vortex generators (VG) cause the near wall flow to be energized before it moves over the downstream convex-concave fairing (DCCF) that is below the faired downstream stern (FDS).
FIG. 6 shows a retrofit to an abutment with a faired abutment nose (FAN), a faired convex-concave abutment nose (FCCN), a faired abutment side (FS), vortex generators (VG), a downstream convex-concave fairing, using interlocking key (IK) sections. That device is a conventionally made concrete or fiber-reinforced composite, or combination of both, vortex generator equipped hydrodynamic fairing that is fit or cast over an existing or new hydraulic structure around the base of the structure and above the footing. The vortex generators (VG) are positioned so as to energize decelerating near-wall flow with higher-momentum outer layer flow. The result is a more steady compact separation and wake and substantially mitigated scour inducing wake vortical (WV) flow as shown by a computational fluid dynamics (CFD) simulation ( FIG. 7 ).
SUMMARY OR THE INVENTION
Discussed are several practical refinements, extensions, additions, and improvements to the manufactured three-dimensional continuous convex-concave fairing with attached vortex generators that was disclosed by Simpson et al. (U.S. Pat. No. 8,348,553), which is incorporated herein by reference. The benefits include actual manufacturing cost reductions, as well as cost reductions by reducing the frequency and complexity of monitoring practices for bridges and elimination of temporary fixes that require costly annual or periodic engineering studies and construction to mitigate scour on at-risk bridges. The probability of bridge failure and its associated liability to the public is substantially avoided since the root cause of local scour is prevented.
In an extension to Simpson et al. (U.S. Pat. No. 8,348,553), in addition to the concrete or fiber-reinforced composite, or combination thereof, hydrodynamic fairing disclosed in Simpson, the present invention in practice is a cast-in-place, pre-cast, or sprayed (“shotcrete”) concrete, metal, or composite, or combinations thereof, hydrodynamic fairing that is fit or cast over one or more existing or new hydraulic structures around the base of these structures and above and around their footings. Molds for the concrete or composite fairing are made from wood and other natural materials, metal or composite materials, or combinations thereof. Such a properly designed fairing prevents scouring vortex formation for both steady and unsteady flows, including oscillatory tidal flows. The vortex generators are constructed of cast-in-place, pre-cast, or sprayed (“shotcrete”) concrete, metal, or composite, or combinations thereof. The product is manufactured using existing metal, concrete, and composite materials technologies well known to those skilled in the art. As such, the product can be produced at minimal cost and with high probability of endurance over a long future period.
While the shape of the Simpson et al. device for bridge piers and abutments is continuously three-dimensional, it can be approximated by piece-wise continuously varying slope and concave-convex-curvature surfaces within definable tolerances that produce the same effects as continuously varying slope and concave-convex-curvature surfaces. The term “piece-wise continuously varying” has a well-known mathematical meaning. As used herein, “piecewise continuously varying” is consistent with that well-known mathematical meaning and means that the surface is formed from an assembly of a plurality of smaller continuously varying slope and curvature surfaces, where discontinuities in slope and/or curvature occur at the intersections of the smaller continuously varying slope and curvature surfaces. In a preferred embodiment, the surface is composed of sections or pieces that individually have curvature in one direction at one location on the surface and intersect adjacent pieces or sections to form the total surface. No scouring vortices are produced with either the continuously varying slope and curvature fairing surface or a piece-wise continuously varying slope and curvature fairing surface, but the piece-wise continuously varying slope and curvature version can be manufactured at a much lower cost.
Therefore, one aspect of the present invention relates to hydraulic structure fairings, preferably having at least one vortex generator thereon. The fairing is installed around the perimeter of the hydraulic structure and extends vertically from the stream bed to a height above the stream bed. The fairing provides a faired shape in a direction of flow and includes streamlined nose and stern fairings, at least one of which has a convex shape along its horizontal planes and concave shape along its vertical planes. The convex and concave shapes intersect at each point on the surface of the streamlined nose and/or stern. Connecting the nose and stern along the direction of flow are side fairings. The nose and/or stern fairings form piecewise continuously varying slope and concave-convex curvature surfaces. The fairings are made of smaller individual pieces with continuously varying slope and curvature surfaces. When the smaller pieces are assembled, they form the fairing with piecewise continuously varying slope and curvature surfaces of the fairing.
Another aspect of the present invention relates to additional types of abutments than shown by experiments by Simpson et al. (U.S. Pat. No. 8,348,553). In addition to the square-cornered abutments discussed in that patent, tests prove that the fairing and vortex generators of the present invention also prevent scouring vortices for wing-wall and spill-through abutments.
In general, as described by Simpson et al. (U.S. Pat. No. 8,348,553), a single fully three-dimensional shape-optimized fairing with the help of vortex generators will prevent scour for a range of angles between the on-coming river flow and the pier centerline from −20° to +20°, with 0° angle defined as where the flow is aligned with the pier centerline axis or side of an abutment. The present invention provides, for bridge piers and abutments, larger angles of attack of up to 45°. Nose and tail sections on a pier may form a dogleg shape and the fairings and vortex generators prevent flow separations.
A further aspect of the present invention relates to improvements for bridge piers and abutments downstream of a bend in a river where there is large-scale swirling approach flow produced by a river bend. The fully three-dimensional shape is modified to meet the requirement of the design that the stream-wise gradient of surface vorticity flux must not exceed the vorticity diffusion or transport rate in the boundary layer, thus preventing the formation of a discrete vortex. Another requirement is that a minimal size of the fairing be used to meet the requirement that the stream-wise gradient of surface vorticity flux must not exceed the vorticity diffusion or transport rate in the boundary layer.
When a pier is in close proximity to an adjacent pier or abutment, the flow between the two hydraulic structures is at a higher speed than if they were further apart. This means that at the downstream region of the pier or abutment there will be a greater positive or adverse stream-wise pressure gradient, which will lead to more and stronger flow separation and scouring vortices. To reduce this separation and possibilities for scour, a more gradual fairing or tail may be used.
As stated by Simpson et al., one can generalize the use of vortex generators for various cases and applications. First, the vortex generators, such as the low drag asymmetric vortex generator disclosed by Simpson et al., should be located on the sides of the fairing well upstream of any adverse or positive pressure gradients and only in flow regions where there are zero pressure gradients or favorable or negative pressure gradients that will persist downstream of the vortex generator for at least one vortex generator length. This results in a well-formed vortex without flow reversal that can energize the downstream flow and prevent separation of the downstream part of the fairing. Second, the vortex generator should be at a modest angle of attack angle of the order of 10 to 20 degrees. Multiple vortex generators may be used on the sides of the fairing, as shown in FIGS. 5 and 6 . The height and maximum width of the vortex generators need not be greater than the thickness of the approaching turbulent boundary layer upstream of the location of the vortex generators. The spacing between the vortex generators up the side of the fairing should be at least twice the maximum width of the vortex generator or twice the length of the vortex generator times the sine of the angle of attack, whichever is larger.
In another further aspect of the present invention, the fairing and vortex generator design features have been expanded for use around the foundation in order to further protect the foundation from the effects of contraction scour, long term degradation scour, settlement and differential settlement of footers, undermining of the concrete fairing segments, and effects of variable surrounding bed levels. Scour of the river bed away from the fairing protected pier or abutment (open-bed scour) will occur first and the river bed level will be lowered away from the pier or abutment. If the front of the foundation of a pier or abutment is exposed to approach flows, then a foundation horseshoe or scouring vortex is formed at the front which will cause local scour around the pier or abutment.
A ramp, preferably a curved ramp, may be placed in front of and attached to the foundation of a fairing protected pier to prevent the formation of the foundation horseshoe vortex and scour around an exposed foundation. A further innovation uses a vortex generator in front of each leading edge corner of the ramp, which will create a vortex that brings available loose open-bed scour materials toward the pier or abutment foundation to protect the pier or abutment. A third innovation uses vortex generators mounted on the sides of the foundation to bring more available loose open-bed scour materials toward the pier or abutment foundation to protect further the pier or abutment.
The innovative scour prevention devices in this present invention belong to the structural countermeasure category. Unlike the conventional, and prior-art before Simpson et al., structural countermeasures, the present scour countermeasure devices are based on a deep understanding of the scour mechanisms of the flow and consideration of structural and hydraulic aspects (Simpson 2001). A hydraulically optimum pier fairing constructed from any permanent solid material, whether for a straight-ahead, swirling, or curved inflow, prevents the formation of highly coherent vortices around the bridge pier or abutment and reduces 3D separation downstream of the bridge pier or abutment with the help of vortex generators, curved leading edge foundation ramp, and tail section.
In addition, these results show that the smooth flow over the pier or abutment produces lower drag force or flow resistance and lower flow blockage because low velocity swirling high blockage vortices are absent. As a result, water moves around a pier or abutment faster above the river bed, producing a lower water level at the bridge and lower over-topping frequencies on bridges during flood conditions for any water level, inflow turbulence level, or inflow swirling flow level. While tested both at model and full scale, there is no place for debris to become caught or no debris build up in front or around a pier or abutment with the fairing and vortex generator of the present invention. In cases where river or estuary boat or barge traffic occurs, the fairing can be constructed to withstand impact loads and protect piers and abutments.
The present invention addresses the FHWA's Plan of Action on scour countermeasures (Hydraulic Engineering Circular No. 23, commonly ‘HEC-23’), such as avoiding adverse flow patterns, streamlining bridge elements, designing bridge pier foundations to resist scour without relying on the use of riprap or other countermeasures, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.
FIGS. 1-4 (labeled “prior art”) show bridge piers and abutments with no prevention of scouring vortices.
FIG. 5 shows the continuous surface fairing (Simpson et al. prior art) at the bottom of a bridge pier with calculated flow streamline patterns.
FIG. 6 shows a continuously varying slope and curvature surface fairing (Simpson et al. prior art) and its components for a vortex preventing design for the bottom of a bridge abutment.
FIG. 7 shows the wall flow pattern from computational fluid dynamics (CFD) simulations at the downstream end of the continuously varying slope and curvature surface fairing (Simpson et al. prior art) for the approach flow aligned with the pier centerline or the straight-ahead case.
FIG. 8 shows surface oil flow results for the modified wing-wall abutment model with vortex generators (VGs). Flow is from right to left. The upward streaks show that the fairing and vortex generator cause the flow to move up the wing-wall abutment. The gray region is produced by a mixture of the oil flow material and waterborne substances at the free surface.
FIG. 9 illustrates the bed level change contours at streamwise X and spanwise Y locations after and before a flow around the wing-wall abutment model with length L into the flow without the fairing and VGs of the present invention.
FIG. 10 shows the bed level change contours at streamwise X and spanwise Y locations after and before flow around the fairing protected modified wing-wall model (length L=159 mm) with vortex generators with no scour observed at any location.
FIG. 11 shows surface oil flow results for a fairing and VGs with modified sharp-leading edge (SLE) spill-through abutment model with 8 upstream VGs. The flow moves up the abutment as it moves downstream, bringing low speed fluid from the bottom of the river and preventing scour. The gray region is produced by a mixture of the oil flow material and waterborne substances at the free surface.
FIG. 12 illustrates bed level change contours at streamwise X and spanwise Y locations after and before flow around the untreated spill-through abutment model (L=159 mm). Note the dark blue scour hole.
FIG. 13 shows bed level change contours at streamwise X and spanwise Y locations after and before flow around the fairing with modified sharp edge spill-through model with VGs (L=229 mm).
FIG. 14 is a top view of the fairing for a 45° dogleg configuration.
FIG. 15 a is an upstream view showing location of VGs on a pier model front right and rear left sides used in 45 degree high angle-of-attack AUR flume tests.
FIG. 15 b is a downstream view of AUR model used in 45° high angle-of-attack AUR flume tests with a laser sheet showing no scour downstream of the model.
FIG. 16 shows the flow downstream of a 90° river bend from computational fluid dynamics (CFD); near-wall streamlines start at X/D=−4 and Y/D=0.13, where X/D and Y/D are streamwise X and spanwise Y locations divided by the pier width D.
FIG. 17 is a top view of flow downstream of a 90° river bend from computational fluid dynamics (CFD); near-wall streamlines start at X/D=−4 and Y/D=0.13, where X/D and Y/D are streamwise X and spanwise Y locations divided by the pier width D.
FIG. 18 shows a cross-section of the swirling secondary flow from CFD downstream of a 90° bend at the streamwise X divided by the pier width D or X/D=−0.30, but upstream of a pier; river surface flow at top of figure moves toward outer river bank on right; near-wall flow moves toward inner river bank on left.
FIG. 19 shows the gravel level after model flume test for a H=12.7 mm high foundation elevation for a pier of width D (H/D=⅙) without a leading edge ramp and a scour hole at corner of foundation due to horseshoe vortex around foundation; note laser sheet for gravel surface measurement.
FIG. 20 shows the gravel level after flume test for a H=12.7 mm high foundation elevation for a pier of width D (H/D=⅙) with a 19 mm high straight-sided curved leading edge ramp buried 6.4 mm in the gravel; note no scour around foundation.
FIG. 21 illustrates that a vortex generator at left upstream ramp ( 7 A) corner creates a counterclockwise (CCW) vortex that brings open-bed scour gravel toward the foundation. Here individual sections or pieces of surface ( 1 A), ( 1 B), ( 1 C), ( 1 D), ( 1 F), and ( 1 G) individually have a continuously varying slope and curvature surface and intersect adjacent pieces or sections to form the piecewise continuously varying slope and concave-convex-curvature surface of the nose.
FIG. 22 shows an example of a pier in close proximity to adjacent piers or abutments with scour at the downstream of the fairing with VGs model without a tail. Laser light sheet shows scour hole downstream of the pier on both sides of centerline and a scour mound along the centerline.
FIG. 23 shows much lower scour around the fairing with VGs model with the tail for the same flume run time as in FIG. 22 .
FIG. 24 is a drawing of a full-scale sheet metal retrofit fairing with VGs for a pier ( 6 A) with a piece-wise continuously varying slope and concave-convex curvature surface, with individual sections or pieces of nose surface ( 1 A), ( 1 B), ( 1 C), ( 1 D), ( 1 E), ( 1 F), ( 1 G), ( 1 H), ( 1 I), and ( 1 J); for the side of the pier ( 2 A); and the stern or tail, with individual sections or pieces of surface ( 4 A), ( 4 B), ( 4 C), ( 4 D), ( 4 E), ( 4 F), ( 4 G), ( 4 H), ( 4 I), and ( 4 J), within definable tolerances that produce the same effects as a continuously varying slope and concave-convex-curvature surface. The leading edge ramp ( 7 A) and pier foundation protecting VGs ( 3 B) mounted on leading edge plate ( 7 B) and ( 3 C) mounted on ( 1 E) and ( 2 A) protect the foundation from open-bed scour.
FIG. 25 illustrates an example of a stainless steel piece-wise continuous surface retrofit fairing for a pier ( 6 A) consisting of individual sections or pieces of surface ( 1 A), ( 1 B), ( 1 C), ( 1 D), ( 1 E), ( 1 F), ( 1 G), ( 1 H), ( 14 and ( 1 J) for the nose and with VGs ( 3 A) (all shown in black) for the side ( 2 A). VGs ( 3 A) create vortices that bring low-speed flow up to prevent scour.
FIG. 26 is a drawing of a full-scale sheet metal retrofit fairing with VGs for a wing-wall abutment ( 6 B) with piece-wise continuously varying slope and concave-convex curvature surfaces consisting of individual sections or pieces of surface ( 1 L), ( 1 M), ( 1 N), ( 1 O), ( 2 B), ( 4 M), ( 4 N), and ( 4 O) within definable tolerances that produce the same effects as a continuously varying slope and concave-convex-curvature surface. VG ( 3 A) reduce the flow separation and free-surface vortex effects while VG ( 3 B) on leading edge horizontal plate ( 7 C 1 ) that is connected to vertical plate ( 7 C 2 ) and VG ( 3 C) protect the foundation from open-bed scour.
FIG. 27 shows an example of a stainless steel piece-wise continuously varying slope and curvature surface retrofit fairing for a wing-wall abutment consisting of individual sections or pieces of surface ( 1 M), ( 1 N), ( 1 O), and ( 2 B) within definable tolerances that produce the same effects as a continuously varying slope and concave-convex-curvature surface. VGs ( 3 A) reduce the flow separation and free-surface vortex effects.
FIG. 28 is a drawing of a full-scale sheet metal retrofit fairing with VGs for a spill-through abutment ( 6 C) with piece-wise continuously varying slope and concave-convex curvature surfaces consisting of individual sections or pieces of surface ( 1 P), ( 1 Q), ( 1 R), ( 2 C), ( 4 P), ( 4 Q), and ( 4 R) within definable tolerances that produce the same effects as a continuously varying slope and concave-convex-curvature surface. VGs ( 3 A) reduce the flow separation and free-surface vortex effects while VG ( 3 B) mounted on leading edge horizontal plate ( 7 D 1 ) connected to vertical plate ( 7 D 2 ) and VG ( 3 C) protect the foundation from open-bed scour.
FIG. 29 is a drawing of a full-scale sheet metal retrofit fairing with VGs for a dogleg pier, which consists of a main pier ( 6 A) with curved nose ( 9 A), curved stern ( 9 B), and piece-wise continuous surfaces ( 5 A), ( 8 A), ( 10 A), and ( 10 D). The piece-wise continuously varying slope and concave-convex curvature surfaces for the fairing nose, consisting of individual sections or pieces of surface ( 1 A), ( 1 B), ( 1 C), ( 1 D), ( 1 E), ( 1 F), ( 1 G), ( 1 H), ( 1 I), and ( 1 J); for the side of the pier ( 2 A), ( 10 B), and ( 10 C); and the tail with individual sections or pieces of surface ( 4 A), ( 4 B), ( 4 C), ( 4 D), ( 4 E), ( 4 F), ( 4 G), ( 4 H), ( 4 I), and ( 4 J) within definable tolerances that produce the same effects as a continuously varying slope and concave-convex-curvature surface. Leading edge ramp ( 7 A) and pier foundation protecting VGs ( 3 B) mounted on leading edge plate ( 7 B) and ( 3 C) mounted on ( 1 E) and ( 2 A) protect the foundation from open-bed scour.
FIG. 30 is a drawing of a full-scale sheet metal retrofit fairing with VGs for a pier with a piece-wise continuously varying slope and curvature tail or stern. The pier consists of a main pier ( 6 A) with curved pier nose ( 9 A) and curved pier stern ( 9 B). Piece-wise continuously varying slope and concave-convex curvature surface for the fairing nose, containing individual sections or pieces of surface ( 1 A), ( 1 B), ( 1 C), ( 1 D), ( 1 E), ( 1 F), ( 1 G), ( 1 H), ( 1 I), and ( 1 J); for the side of the pier ( 2 A); and the tail, with individual sections or pieces of surface ( 4 S), ( 4 T), and ( 4 U), within definable tolerances that produce the same effects as a continuously varying slope and concave-convex-curvature surface. The leading edge ramp ( 7 A) and pier foundation protecting VGs ( 3 B) mounted on leading edge plate ( 7 B) and ( 3 C) mounted on ( 1 E) and ( 2 A) protect the foundation from open-bed scour.
FIG. 31 is a perspective top view drawing of concrete forms for the piece-wise continuously varying slope and curvature fairing during construction of a new pier: ( 11 A) for the nose, ( 12 A) for the sides, and ( 13 A) for the stern.
FIG. 32 shows an example of steel forms 11 A and 12 A for the piece-wise continuously varying slope and curvature fairing for construction of a new concrete pier 6 A.
FIG. 33 is a perspective view drawing of concrete forms for the piece-wise continuously varying slope and curvature fairing during construction of a new wing-wall abutment ( 6 D): ( 12 C) for the nose, ( 11 B) for the upstream bend, ( 12 B) for the sides, ( 13 B) for the downstream bend, ( 12 D) for the stern, ( 14 A) for the upstream corner fairing, and ( 14 B) for the downstream corner fairing.
FIG. 34 shows an example of steel concrete forms ( 11 B), ( 12 B), ( 12 C), and ( 14 A) for the piece-wise continuously varying slope and curvature fairing for construction of a new wing-wall abutment ( 6 D).
FIG. 35 is a drawing of a finished new construction wing-wall abutment ( 6 D) with the piece-wise continuously varying slope and curvature concrete fairing containing continuously varying slope and curvature pieces ( 1 T), ( 2 D), ( 2 E), ( 2 F), ( 4 W), ( 5 B), and ( 5 C). VGs ( 3 A) reduce the flow separation and free-surface vortex effects while VG ( 3 B) mounted on leading edge horizontal plate ( 7 E 1 ) connected to vertical plate ( 7 E 2 ) and VG ( 3 C) protect the foundation from open-bed scour.
FIG. 36 is a perspective view drawing of steel concrete forms for the piece-wise continuously varying slope and curvature fairing during construction of a new spill-through abutment ( 6 E): ( 16 A) for the nose, ( 11 C) for the upstream bend, ( 12 E) for the sides, ( 13 C) for the stern bend, ( 16 B) for the stern, ( 14 C) for the upstream corner fairing, and ( 14 D) for the downstream corner fairing.
FIG. 37 shows an example of steel concrete forms ( 16 A), ( 11 C), ( 12 E), and ( 14 C) for the piece-wise continuously varying slope and curvature fairing for construction of a new spill-through abutment ( 6 E). VGs ( 3 A) are shown mounted on the abutment for flow separation and surface vortex control.
FIG. 38 is a drawing of a finished new construction spill-through abutment ( 6 E) with the piece-wise continuously varying slope and curvature concrete fairing containing continuously varying slope and curvature pieces ( 1 U), ( 1 V), ( 1 W), ( 1 X), ( 2 G), ( 4 U), ( 4 V), ( 4 W), ( 4 X), ( 5 D) and ( 5 E). VGs ( 3 A) are mounted on the abutment for flow separation and surface vortex control while VG ( 3 B) mounted on leading edge horizontal plate ( 7 F 1 ) connected to vertical plate ( 7 F 2 ) and VG ( 3 C) protect the foundation from open-bed scour.
DETAILED DESCRIPTION
Because bridge piers and abutments are the most common hydraulic structures, in the following description bridge piers and abutments are used as examples. The local vortex preventing scour countermeasure devices and methods described herein may be extended to other like hydraulic substructures. The present invention relates to fairings, preferably together with a vortex generator (VG), for preventing scour in the vicinity of a hydraulic structure. The fairing contains a piece wise continuously varying slope and concave-convex curvature surface. The piecewise continuously varying slope and curvature surface is made of a plurality of smaller surfaces that are assembled to form the piecewise continuously varying slope and curvature surface. Each of the plurality of smaller surfaces itself is a continuous surface. When the smaller surfaces are assembled to form the fairing surface, discontinuities in slope and curvature occur at their intersection, thus giving rise to the piecewise continuously varying slope and curvature fairing surface. The piecewise continuously varying slope and curvature fairing is generally composed of a nose section, side sections, and stern section. The nose section is the upstream most section; the stern section is the downstream most section, and the side sections connect the nose and stern sections on either side of the hydraulic structure.
The piecewise continuously varying slope and convex-concave fairing may be formed on the hydraulic structure as a retrofit or a new construction. A retrofit is a surface that is added on to an existing hydraulic structure to reduce scouring. A new construction is a surface that is constructed as part of the original hydraulic structure. The fairing surface may be formed from various materials, such as concrete, steel, sheet metal, fiberglass, etc. For a retrofit, individual smaller surfaces may be formed, e.g., by casting or molding, and transported to and assembled on the hydraulic structure. Here, the individual smaller surfaces may be premanufactured and interlock using matching keys or alignment surfaces among individual premanufactured elements. For new construction, the hydraulic structure is designed with the piecewise continuously varying slope and curvature fairing and constructed along with the hydraulic structure. In new construction, the piecewise design allows the mold to be built in smaller sections for easy transport to and assembly at the construction site. The fairing surface may be constructed of cast-in-place concrete, pre-cast concrete, sprayed concrete, metal, composite, fiber reinforced polymers, or combinations thereof.
Referring to the drawings, especially FIGS. 24, 26, 28, 29, 30, 35, and 38 , which show global views of several embodiments of the present piecewise continuously varying slope and curvature fairing surface. The components of the piecewise continuously varying slope and curvature fairing surface include one or more of the following:
a. Smaller continuously varying slope and curvature surfaces ( 1 A) to ( 1 X) are assembled together to form the nose section of the piecewise continuously varying slope and curvature fairing. As illustrated in FIG. 24 , each of the individual smaller continuously varying slope and curvature surfaces ( 1 A), ( 1 B), ( 1 C), ( 1 D), ( 1 E), ( 1 F), ( 1 G), ( 1 H), ( 1 I), ( 1 J) individually has curvature in one direction at one location on each surface and intersect adjacent pieces to form the piecewise continuously varying slope and concave-convex-curvature surface of the nose section ( FIGS. 24, 29 , an 30 ). Smaller continuously varying slope and curvature surfaces ( 1 L), ( 1 M), ( 1 N), and ( 1 O) apply to a retrofit to a wing-wall abutment ( FIG. 26 ) while ( 1 P), ( 1 Q), and ( 1 R) apply to a retrofit to a spill-through abutment ( FIG. 28 ). New concrete finished surfaces ( 1 T) and ( 1 U), ( 1 V), ( 1 W), and ( 1 X) apply to new wing-wall ( FIG. 35 ) and spill-through abutments ( FIG. 38 ), respectively. b. Smaller continuously varying slope and curvature surfaces ( 2 A) through ( 2 G) form the side section(s) of the piecewise continuously varying slope and curvature fairing. c. ( 3 A) through ( 3 C) are specially designed vortex generators with ( 3 A) being a vortex generator assembly, ( 3 B) being a leading edge vortex generator, and ( 3 C) being a foundation vortex generator. d. Smaller continuously varying slope and curvature surfaces ( 4 A) through ( 4 AA) form the stern section of the piecewise continuously varying slope and curvature fairing. As illustrated in FIG. 24 , each of the individual smaller continuously varying slope and curvature surfaces ( 4 A), ( 4 B), ( 4 C), ( 4 D), ( 4 E), ( 4 F), ( 4 G), ( 4 H), ( 4 I), ( 4 J) individually has curvature in one direction at one location on each surface and intersect adjacent pieces or sections to form the piecewise continuously varying slope and concave-convex-curvature surface of the stern section ( FIGS. 24 and 29 ). Sections ( 4 M), ( 4 N), and ( 4 O) apply to a retrofit to a wing-wall abutment ( FIG. 26 ), while ( 4 P), ( 4 Q), and ( 4 R) apply to a retrofit to a spill-through abutment ( FIG. 28 ). Sections ( 4 S), ( 4 T), and ( 4 U) apply to a faired tail assembly ( FIG. 30 ). New concrete finished surfaces ( 4 T) and ( 4 X), ( 4 Y), ( 4 Z), and ( 4 AA) apply to new wing-wall ( FIG. 35 ) and spill-through abutments ( FIG. 38 ), respectively. e. ( 5 A) through ( 5 D) are a faired or curved cylindrical pier or abutment surface. Here, ( 5 A) is a pier nose in a dogleg retrofit ( FIG. 29 ). Sections ( 5 B) and ( 5 C) are curved corners for a new construction wing-wall abutment ( FIG. 35 ), while sections ( 5 D) and ( 5 E) are curved corners for a new construction spill-through abutment ( FIG. 38 ). f. ( 6 A) through ( 6 E) are existing or new bridge piers or abutments ( FIGS. 24, 26, 28, 29, 30, 35, and 38 ). g. ( 7 A) is a foundation leading edge ramp ( FIGS. 24, 29, and 30 ). The ramp ( 7 A) is positioned to prevent the formation of a horseshoe vortex that would scour the sides of the foundation. h. ( 7 B) through ( 7 F 2 ) are upstream leading edge horizontal and vertical plates on which leading edge vortex generators ( 3 B) are mounted. ( 7 B) is a horizontal plate used on a pier nose (leading edge plate) ( FIGS. 24, 29, and 30 ). The leading edge plate 7 B is positioned so that the VGs ( 3 B) can be located upstream of the side edge of the leading edge ramp ( 7 A). ( 7 C 1 ), ( 7 D 1 ), ( 7 E 1 ), and ( 7 F 1 ) are upstream leading edge horizontal plates for abutments ( FIGS. 26, 28, 35, 38 ). ( 7 C 2 ), ( 7 D 2 ), ( 7 E 2 ), and ( 7 F 2 ) are vertical plates mounted to abutment foundations on which the horizontal plates are attached ( FIGS. 26, 28, 35, 38 ). i. ( 8 A) is a cylindrical pier downstream surface ( FIG. 29 ). j. ( 9 A) and ( 9 B) are existing cylindrical pier nose ( 9 A) or stern ( 9 B) ( FIGS. 24 and 30 ). k. ( 10 A), ( 10 B), ( 10 C) and ( 10 D) are continuously varying slope and curved pier nose or tail extensions ( FIG. 29 ). These nose or tail extensions are added to the pier ( 6 A) to provide a piece-wise continuously varying slope and curvature surface to the s-shape of the final structure. l. ( 11 A), ( 11 B), and ( 11 C) are molds for new construction piece-wise continuously varying slope and curvature three-dimensional convex-concave pier or abutment hydraulic structure nose or leading edge fairing ( FIGS. 31-34 and 36-37 ). m. ( 12 A), ( 12 B), ( 12 C), ( 12 D), and ( 12 E) are molds for new construction piece-wise continuously varying slope and curvature cylindrical curved side fairings for piers or abutments ( FIGS. 31-34 and 36-37 ). n. ( 13 A), ( 13 B), and ( 13 C) are molds for new construction piece-wise continuously varying slope and curvature three-dimensional convex-concave pier or abutment hydraulic structure stern or downstream fairing ( FIGS. 31, 33, and 36 ). o. ( 14 A), ( 14 B), ( 14 C), and ( 14 D) are molds for new construction piece-wise continuously varying slope and curvature three-dimensional convex-concave abutment hydraulic structure corner fairing ( FIGS. 33-34 and 36-37 ). p. ( 16 A) and ( 16 B) are molds for new construction piece-wise continuously varying slope and curvature leading edge and trailing edge fairings for abutment hydraulic structures ( FIG. 36 ).
The VGs ( 3 A, 3 B, or 3 C) used here are each a tetrahedron-a polyhedron composed of four triangular faces, three of which meet at each vertex. This shape is chosen specifically because it acts to deter build-up of debris that is present in flood conditions. The tetrahedron design of Simpson et al. (U.S. Patent Application Publication No. 2011/0315248 which is incorporated herein by reference) may be appropriate for the present invention. Other kinds of vortex generators used to control boundary layer separation are described, e.g., by Wheeler (U.S. Pat. No. 5,058,837, which is incorporated herein by reference may also be used in the present invention, but may snag debris, whereas the Simpson et al. VGs will not. The VGs may be constructed of cast-in-place concrete, pre-cast concrete, sprayed concrete, metal, composite, fiber reinforced polymers, or combinations thereof. VGs are always positioned in regions of zero or negative streamwise pressure gradients in order to create a stream-wise vortex. The VGs are placed at locations where: (1) they can be effective in creating stream-wise vortices that bring higher velocity fluid toward the surface wall, e.g. VGs 3 A; or (2) they can be effective to create stream-wise vortices that bring river bed materials close to the foundation, e.g. VGs ( 3 B and 3 C). The VGs ( 3 A) are located at least one vortex generator length upstream of where the stream-wise pressure gradients become positive. The spacing between them must be great enough that they allow the vortex on an adjacent VG to form, generally at least ½ of a VG length. They cause higher velocity fluid to move toward the wall and mix and energize the near-wall fluid. This more energetic fluid will move further along a streamlined surface than otherwise, thus producing a smaller less energetic and scouring downstream separation vortex. This reduced rear or stern separation has lower downstream velocities and much less downstream scour. The VG ( 3 B) is initially buried under the surrounding river bed material in front of the pier nose. Under intense scouring conditions, such as during floods or other high-flow-speed events, this river bed material in front of the nose of the pier is scoured away, revealing the VGs ( 3 B). Each VG ( 3 B) then generates a stream-wise vortex that pulls river-bed material toward the foundation of the pier, thereby protecting the foundation from further scour. Likewise, the VG 3 C is initially buried under the surrounding river bed material and mounted on the side of the nose ( 1 E). Under intense scouring conditions, such as during floods or other high-flow-speed events, this river bed material on the side of the nose of the pier is scoured away, revealing the 3 C VG. The 3 C vortex generator then generates a stream-wise vortex that pulls river-bed material toward the foundation of the pier, thereby protecting the foundation from further scour. The VG ( 3 C) is located at least 2 VG lengths downstream of VG ( 3 B).
As best shown in FIGS. 24-38 , the exemplary embodiments are drawn to pier structures ( FIGS. 24-25, 29-32 ) and abutments structures ( FIGS. 26-28 and 33-38 ). The exemplary pier may be a straight pier ( FIGS. 24-25 and 30-32 ) or dogleg pier ( FIG. 29 ). The straight pier may have a stern section that is a mirror image of the nose section ( FIG. 24 ). In that embodiment, the piecewise continuously varying slope and curvature nose and stern section may be made of similarly shaped smaller continuously varying slope and curvature surfaces. Here, smaller continuously varying slope and curvature surfaces ( 1 A) and ( 4 A) are similar, ( 1 B) and ( 4 B) are similar, ( 1 C) and ( 4 C) are similar, etc. Preferably, however, the upstream end of the nose section contains a ramp ( 7 A) attached to upstream surface ( 1 A), more preferably with vortex generators ( 3 B) attached to the upstream corners of the ramp ( 7 A). No ramp is needed down stream of stern section.
In an alternative embodiment, as illustrated in FIG. 30 , the stern section contains a tapered shape rather than a rounded shape of the nose section. This tapered shape is formed by smaller continuously varying slope and curvature surfaces ( 4 S), ( 4 T), and ( 4 U). The tapered stern reduces the stream-wise positive pressure gradient and reduces the possibility of a massive separation that will result in scour downstream. In a narrow surrounding channel, as shown in FIG. 23 , without the tapered stern there would be greater stream-wise positive pressure gradients than if there was no narrow channel, with greater separation and scour. Also with the tapered stern, a smaller continuously varying slope and curvature surface ( 4 S) rises to a height higher than the nose and side sections of the piecewise continuously varying slope and curvature fairing. The smaller continuously varying slope and curvature surface ( 4 S) does not need to be as high as the pier ( 6 A); it just needs to be high enough to keep the flow downstream of the stern ( 9 B) in FIG. 30 from coming down to the river bed. The smaller continuously varying slope and curvature surfaces ( 4 T and 4 U) are also positioned to produce lower positive pressure gradients, weaker separations, and less scour.
In another embodiment, as illustrated in FIG. 29 , the pier may be retrofitted to contain a dogleg shape. For piers that have a large angle of incidence to the on-coming river flow, there are separations at the nose and the stern of the pier with huge scouring vortices. The nose ( 5 A) of the dogleg is aligned with the on-coming flow direction to prepare the flow to encounter the vortex generators ( 3 A) shown in FIG. 29 . With the dogleg pier, the nose and stern sections are constructed similarly as for the straight pier discussed above. However, to form the dogleg, pier nose sections ( 10 A) and ( 10 B) and pier stern sections ( 10 C) and ( 10 D) are also added. The pier nose section ( 10 A) is added to the nose of the pier ( 6 A); and the pier nose section ( 10 B) are added between the side section ( 2 A) and the smaller continuously varying slope and curvature surfaces ( 1 F), ( 1 G), ( 1 H), ( 1 I), ( 1 J). In addition, a front pier nose section ( 5 A) is also added in front of the pier nose section ( 10 A). The stern section is also formed symmetrical to the nose section. In a preferred embodiment, the dogleg pier also contains a ramp ( 7 A) attached to upstream surface ( 1 A), more preferably with vortex generators ( 3 B) attached to the upstream corners of the ramp ( 7 A). The VGs energize the flow so that when it moves around to the original side of the pier it will have less separation. A similar VG arrangement would be located on the opposite (hidden and unseen in FIG. 29 ) wall, just upstream about one VG length from the end of the stern ( 9 B).
The exemplary abutments may be a wing-wall abutment ( FIGS. 26-27 and 33-35 ) or a spill-through abutment ( FIGS. 28 and 36-38 ). As best illustrated in FIGS. 26 and 35 , the piecewise continuously varying slope and curvature fairing surface for the wing-wall abutment includes smaller continuously varying slope and curvature surfaces ( 1 L), ( 1 M), ( 1 N), ( 1 O) forming the leading edge of the fairing; side section surfaces ( 2 B); and smaller continuously varying slope and curvature surfaces ( 4 M), ( 4 N), ( 4 O) forming the trailing edge of the fairing. A leading edge horizontal plate ( 7 C 1 ) and a vertical plates ( 7 C 2 ) may be mounted to the abutment foundations upstream of the piecewise continuously varying slope and curvature fairing, preferably for mounting of the leading edge VG ( 3 B).
As best illustrated in FIGS. 28 and 38 , the piecewise continuously varying slope and curvature fairing surface for the spill-through abutment includes smaller continuously varying slope and curvature surfaces ( 1 P), ( 1 Q), ( 1 R) forming the leading edge of the fairing; side section surfaces ( 2 C); and smaller continuously varying slope and curvature surfaces ( 4 P), ( 4 Q), ( 4 R) forming the trailing edge of the fairing. A leading edge horizontal plate ( 7 D 1 ) and a vertical plates ( 7 D 2 ) may be mounted to the abutment foundations upstream of the piecewise continuously varying sloe and curvature fairing, preferably for mounting of the leading edge VG ( 3 B).
As mentioned above the piecewise continuously varying slope and curvature fairing surface may be retrofitted on to an existing hydraulic structure or be a new construction. As a retrofit, the individual smaller continuously varying slope and curvature surfaces may be formed, e.g. by stamped sheet metals, and attached to the hydraulic structure using fasteners, such as screws, rivets, anchors, etc. Once installed, the individual smaller continuously varying slope and curvature surfaces cooperate to form the piecewise continuously varying slope and curvature fairing surface.
For a new construction, a mold is generally built around the hydraulic structure and concrete is poured into the mold to form the piecewise continuously varying slope and curvature fairing surface. Exemplary molds are shown in FIGS. 31-32 for a straight pier, FIGS. 33-34 for a wing-wall abutment, and FIGS. 36, 37 for a spill-through abutment.
Without further description, it is believed that one of ordinary skill in the art can, using the preceding description and the following illustrative examples, make and utilize the devices and practice the methods of the present disclosure. The following examples re given to illustrate the present disclosure. It should be understood that the disclosure is not to be limited to the specific conditions or details described in the examples.
Examples of Scour-Vortex-Preventing Fairing and Vortex Generator Concepts for Wing-Wall and Spill-Through Abutments
Applications to more types of abutments than shown by the experiments by Simpson et al. are given. In addition to the square-cornered abutments discussed in that patent, scale model tests prove that the piece-wise continuously varying slope and curvature fairing with the help of vortex generators prevent scouring vortices for wing-wall and spill-through abutments. Research by Sheppard et al. (2011) using hundreds of sets of scour data and sponsored by the National Co-operative Highway Research Program (NCHRP) shows that model scale bridge scour experiments produce much more severe scour depth to pier size ratios than the scour depth to pier size ratios observed for full-scale cases due to scale effects. Thus, all of the model scale flume tests presented here show more scour than at full scale (Simpson 2013). As explained below, FIGS. 8-13 show the key results that the fairing and VG products prevent the formation of scouring vortices and scour for wing-wall and spill-through abutments. FIG. 8 shows surface oil flow results for a fairing for a wing-wall abutment with VGs. The mixture of yellow artist oil paint and mineral oil flows with the skin friction lines. Streaks of this mixture are first painted about perpendicular to the flow direction on a black painted surface. The right to left flow causes some oil to be carried downstream in a local flow direction, which can be observed against the black painted surface. FIG. 8 clearly shows that the effects of the fairing and VG products are to bring lower velocity flow up from the flume bottom and prevent the scour around the bottom of the abutment.
FIG. 9 shows the deep scour holes for the same wing-wall abutment without fairing and VG. This figure shows that when there is no scour protection by the use of the piece-wise continuously varying slope and curvature fairing and VGs, there will be considerable scour. Here X is the stream-wise location, Z is the spanwise location, and L is the dimension of the abutment into the flow. With a fairing modified wing-wall abutment with VGs, there is not only no scour around the model base, but there is no open bed scour hole farther downstream of the model around X/L=2 as shown in FIG. 10 . This is due to the effect of VGs on the surface vortex which caused the scour hole farther downstream of the model for the untreated case. The VGs generate counter-rotating vortices which diffuse and reduce the strength of the free-surface generated vortex. No scour occurred around the contraction and near the base of the modified wing wall with VGs. No open bed scour was observed.
Some flow and scour depth results are given for a flume test for a faring modified spill-through abutment with VGs. This test has been performed under the same flow conditions and flume geometry as for the spill-through abutment without fairing and VGs.
FIG. 11 is a surface oil flow for this case that clearly shows that the fairing and VG products bring lower velocity flow up from the flume bottom and prevent scour around the bottom of the abutment (Simpson et al. 2013). FIG. 12 shows the deep scour holes for the unmodified spill-through abutment. With a fairing modified spill-through abutment with VGs, FIG. 13 shows no scour around the upstream contraction and near the base of the modified spill-through abutment due to the fairing. Although there is still a very minor scour at the downstream of the model, its max depth (−0.02 L) is much lower than that for an untreated abutment. The downstream open bed scour due to the free surface vortex has been greatly reduced.
Example for Bridge Piers and Abutments at High Angles of Attack—45 Deg Dogleg Configuration
Here an extension is disclosed for bridge piers and abutments at larger angles of attack of up to 45°. Nose and tail extension sections on a pier form a dogleg shape ( FIG. 14 ) and vortex generators prevent separations. The centerline of the piece-wise continuously varying slope and curvature curved pier nose and tail extensions and the nose and tail of the fairing are aligned with the on-coming flow direction. VGs are used to energize the near-wall flow upstream of the adverse pressure gradient regions around the pier and prevent separation and scour.
Model scale experiments in the AUR flume were performed that confirm that this design prevents scour. The VGs are attached on both front and rear fairings as shown in FIGS. 15 a and 15 b . The VGs are 76 mm long and 19 mm high. The free-stream velocity is 0.58 m/s and the flow speed near the VGs on the fairings is about 0.61 m/s, which caused scour when the VGs were not used. As shown in the photos below, there is no scour around the model.
Manufacturing and installation processes and methods would be the same as for bridges at lower angles of attack that do not need the dogleg. However there are increases in costs due to the addition of the additional components required for the stainless steel dogleg on a pier (Simpson 2013).
Example of Fairing with VG for a Swirling River Downstream of a Bend
Here, another extension is disclosed for bridge piers and abutments downstream of a bend in a river where there is large-scale swirling approach flow produced by the river bend. The fully three-dimensional shape is modified from the straight ahead case to meet the first requirement of the design that the stream-wise gradient of surface vorticity flux must not exceed the vorticity diffusion or transport rate in the boundary layer, thus preventing the formation of a discrete vortex. Another requirement is that a minimal size of the fairing be used that meets the first requirement.
FIGS. 16-18 show results for a thick upstream inflow boundary layer. The pier is located downstream of a 90° river bend. Pier model width D is 0.076 m wide with a 27.5 mps flow. The inflow boundary layer thickness=0.25 m. The near-river bottom flow moves toward the inner curved river bank under the large pressure gradient between the inner and outer river banks. The near free-surface flow moves toward the outer curved river bank under the effect of flow inertia. A large stream-wise vortex across the entire river is produced by the end of the curved section of the river.
This swirling flow is the upstream inflow to the pier. This inflow allows one to modify the nose shape from the straight ahead case shape and meet the vorticity flux requirement mentioned above. There is no separation or rollup of a discrete vortex that will cause scour.
Example Foundation Scour Vortex Prevention Device: The Curved Leading Edge Ramp
Aspects of the fairing and VG design features have been expanded by using a curved leading edge ramp in front of a pier or abutment foundation in order to further protect the foundation from the effects of contraction scour, long term degradation scour, settlement and differential settlement of footers, undermining of the concrete faring segments, and effects of variable surrounding bed levels. This leading edge ramp prevents undermining of the foundation when the fairing and VG products are installed on a pier or abutment.
First, when the fairing and VG design features are installed on a bridge pier or abutment, the fairing prevents any scouring horseshoe vortex formation and down flow of higher velocity water from upstream and the VGs cause low speed water flow near the river bottom next to the pier or abutment to move up the pier or abutment, as shown in FIGS. 8 and 11 . Thus, the velocities, shearing stresses on the bottom of the pier or abutment, and pressure gradients will be lower than without the fairing and VG. Presumably the surrounding river bed will be at the same height or level as the top edge of the fairing at the bottom of the pier or abutment after installation. As all AUR flume studies have shown, under these conditions scour of the open bed material occurs at a lower river speed before scour of the material around the base of the fairing occurs.
What this means is that scour of the river bed away from the fairing protected pier or abutment will occur first and that the river bed level will be lower away from the pier or abutment. If a pier or abutment foundation is exposed, it will still have a higher immediate surrounding river bed level than farther away. Even so, it is desirable to further arrest scour around the foundation to prevent high speed open bed scour from encroaching on the river bed material next to the foundation.
Second, if the front or upstream part of the foundation of a pier or abutment is exposed to approach flows, then a foundation horseshoe or scouring vortex is formed at the front which will cause local scour around the pier or abutment. This suggests that a curved ramp be mounted in front of the foundation to prevent the formation of this foundation horseshoe vortex. Additional components around the sides of the foundation are also another consideration, but because they do not produce a flow that moves up the fairing, they will not produce any benefit.
Based on these facts, flume tests were conducted with 3 foundation leading edge ramp configurations: (1) an exposed rectangular foundation with no front ramp protection, (2) an upstream curved foundation ramp with trapezoidal spanwise edges to produce a stream-wise vortex to bring open bed materials toward the foundation, and (3) a curved upstream foundation ramp with straight span-wise edges. Gravel A, which is the smallest gravel used in the AUR flume and has a specific gravity of 3.7 and the size of 1.18-1.4 mm, are distributed around the faring model for each test.
Flume tests for scour depth were made for these 3 cases with H=12.7 mm high foundation elevation (H/D=⅙) with gravel A around the foundation with or without a leading edge ramp (Simpson 2013). These tests were done with a flow speed of 0.6 mps at which the pea gravel in the open bed begins to be carried downstream. Without a ramp, as expected, the scour occurred at the front corners of the model due to the front foundation horseshoe vortex, as shown in FIG. 19 . There is gravel accumulation along the pier side near the location of VGs on the fairing on the pier, which is caused by the horseshoe vortices and downstream upflow generated by these VGs.
For the H=12.7 mm high foundation (H/D=⅙) with a curved ramp and trapezoidal sides, the scour occurs at the front corner of the ramp and more gravel accumulates along the pier side around the VGs (Simpson 2013). Furthermore, there is a gravel mound at the downstream model edge. The gravel carried from the upstream are accumulated along the pier side and at the pier end. Therefore, the tested trapezoidal front ramp is not effective to reduce or prevent the scour at the upstream end of the foundation when the edge of the foundation is higher than the surrounding bed.
For the H=12.7 mm high elevation (H/D=⅙) with 19 mm high curved straight-sided ramp, scour around the front of the foundation is not detectable ( FIG. 20 ) since the ramp is submerged 6.4 mm and the blunt nose of the ramp is not exposed to the flow. The scour hole and mound along the side is also minimized. The scour hole along the pier side is away from the pier foundation several piers heights and the gravel accumulate on the pier side downstream of the VG. This is a desired result since no gravel next to the foundation is removed. To the contrary, downstream of the VGs gravel from the open bed is brought toward the foundation edge, which serves to further protect the foundation from further scour. Results for a 19 mm high foundation produced very similar results (Simpson 2013). In summary, all of these foundation tests show that a leading edge straight-sided curved ramp prevents scour around a foundation when there is open bed scour.
Example of Initially Submerged Pier and Abutment Vortex Generators to Protect a Foundation from Open-Bed Scour
In addition to the curved leading edge ramp mentioned above, a further innovation to protect a foundation from open-bed scour uses a vortex generator at 20° angle of attack in front of each leading edge corner of the ramp, which will create a vortex that brings available loose open-bed scour materials toward the pier or abutment foundation to protect the pier or abutment, as shown in FIG. 21 for a pier. Like for the ramp, when there is no high velocity flow and the curved leading edge ramp ( 7 ) is covered with river bed material, the vortex generators ( 3 B) are also covered with bed material. When the water flow speed approaching the pier or abutment is large enough to cause open-bed scour, the bed material over the curved leading edge ramp and the vortex generators will eventually be removed exposing both the ramp and vortex generators. Both the curved leading edge ramp and the vortex generators create vortices that bring loose open-bed material toward the foundation to further protect it from scour.
Another innovation uses VGs ( 3 C) mounted on the sides of the foundation to bring more available loose open-bed scour materials toward the pier or abutment foundation to protect further the pier or abutment. These VGs are initially submerged below the surface of the river bed, but are exposed when there is high velocity flow and open-bed scour. Properly oriented, they create vortices that bring open-bed scour material towards the foundation for protection.
Example Pier and Abutment Stern or Tail Fairings to Further Prevent Scour
When a pier is in close proximity to an adjacent pier or abutment, the flow between the two hydraulic structures is at a higher speed than if they were further apart. This means that at the downstream region of the pier or abutment there will be a greater positive or adverse stream-wise pressure gradient, which will lead to more and stronger flow separation ( FIG. 22 ). To reduce this separation and possibilities for scour, a more gradual fairing or tail can be used, as shown in FIG. 23 for a pier. A similar more gradual fairing can be used for abutments.
The test with a narrow flume width was conducted without a tail first in order to compare with the tail case. The upstream free-stream flow is 0.56 m/s and the flow speed is about 0.66-0.67 m/s between the model and the side wall. After 50 minutes the scour holes downstream of the model are symmetric on each side of the centerline and are caused by the separated vortices from the rear fairing, as shown in FIG. 22 . The corresponding scour deposition mound is located along the centerline. A video clip was recorded for this scour development.
A tail is attached to the rear fairing as shown in FIG. 23 in order to prevent the separation from the rear fairing which causes this scour hole at the downstream of the model. The tail in this example is a NACA0024 airfoil that is 76 mm thick which is the width of the model pier, 178 mm long and 203 mm high.
The tail on the model was tested with the same flume conditions as without a tail, 0.56 m/s free-stream velocity and 0.66-0.67 m/s between the model and the side wall. After a 50 minutes run with the same flow speed as before, there are only very minor scour holes generated at the downstream of the model.
Examples of Additional Construction and Mold Materials and Piece-Wise Continuous Concave-Convex Curvature Surfaces
In an extension to Simpson et al., in addition to the concrete or fiber-reinforced composite, or combination thereof, hydrodynamic fairing disclosed in that patent, the present invention in practice is a cast-in-place, pre-cast, or sprayed (“shotcrete”) concrete, metal, or composite material, or combinations thereof, hydrodynamic fairing that is fit or cast over one or more existing or new hydraulic structures around the bases of these structures and above and around their footings. Molds for the concrete or composite fairing are made from wood and other natural materials, metal or composite materials, or combinations thereof. Such a properly designed fairing, as described by Simpson et al., prevents scouring vortex formation for both steady and unsteady flows, including oscillatory tidal flows. The product is manufactured using existing metal, concrete, and composite materials technologies well known to professionals. As such, the product can be produced at minimal cost and with high probability of endurance over a long future period.
While the shape of the fairing for bridge piers and abutments is fully three-dimensional, as described in detail by Simpson et al., it can be approximated by piece-wise continuously varying slope and concave-convex-curvature surfaces within definable tolerances that produce similar scouring vortex prevention effects as continuously varying slope and concave-convex-curvature surfaces. No scouring vortices are produced in either case, but the piece-wise continuously varying slope and curvature version can be manufactured at a much lower cost.
Retrofit Bridge Pier and Abutment Fairing
An attractive manufacturing alternative for a retrofit bridge fairing uses stainless steel (SS) or even weathering steel. Stainless steel was considered for both the double curvature end sections and the cylindrical sides of the fairing. Its corrosion resistance gives it a lifetime of 100 years even in seawater environments, using a proper thickness, construction methods, and type of SS. It is an effective way to reduce weight and the cost associated with casting custom reinforced concrete structures. Another benefit is that the SS VGs can be welded directly onto the side sections instead of having to be integrated into the rebar cage of a reinforced concrete structure.
Typical example costs for each of these manufacturing approaches were developed from current cost information and quotations from concrete and steel fabricators. It is clear that stainless steel is the best choice for bridge retrofits.
FIGS. 24 and 25 show a full-scale sheet stainless steel retrofit with pier fairing with piece-wise continuously varying slope and concave-convex-curvature surfaces within definable tolerances that produce the same effects as continuously varying slope and concave-convex-curvature surfaces. FIG. 26-30 show full-scale sheet stainless steel retrofit fairings with piece-wise continuously varying slope and concave-convex-curvature surfaces for a wing-wall and spill-through abutments. These fairings and VGs for a dogleg pier and a pier with a tail fairing are within definable tolerances that produce the same effects as continuously varying slope and concave-convex-curvature surfaces. Bulkheads under the sheet-metal skin support the piece-wise continuously varying slope and concave-convex curvature surface.
FIGS. 24, 29, and 30 show the leading edge ramp ( 7 ) for piers. FIGS. 24-30 show scour preventing vortex generators 3 A, 3 B, and 3 C for piers and abutments.
New Construction
In the case with new construction, essentially the difference between the way cast-in-place bridge piers and abutments are constructed currently without the fairing and in the future with the fairing products, is that steel forms for the concrete are used, as shown in FIGS. 31-34, 36, and 37 for piers and abutments. All standard currently used concrete construction methods and tools can be used. During the bridge design phases, the bridge pier or abutment foundation or footer top surface width and length would need to be large enough to accommodate the location of the concrete fairing on top. Rebar needed for the fairing would be included in the foundation during its construction. Stainless steel rebar for welding to the stainless steel vortex generators mounting plates on the surface need to be used for specific locations.
Standard methods for assembling forms and pouring the concrete will be used, as discussed in ACI 318-11. The contractor simply needs to replace the currently used forms for the lowest level of the pier or abutment above the foundation with the fairing forms. The fairing steel forms can be mounted and attached to the foundation forms. The tops of the steel fairing forms on opposite sides of a pier can be attached together with steel angle to completely contain the concrete for the foundation and the fairing. Like current methods, after the fairing and foundation concrete has cured sufficiently, the fairing and foundation forms would be removed. Currently used forms for the next higher portions of the pier or abutment can then be mounted in place for further cast-in-place concrete. Estimated incremental costs of adding the fairing to new construction for additional rebar, concrete, labor, fairing forms, and transportation of forms for various width pier construction shows that the new construction cost is about ⅓ of retrofit costs, so the best time to include the fairing on piers is during new construction.
Although certain presently preferred embodiments of the invention have been specifically described herein, it will be apparent to those skilled in the art to which the invention pertains that variations and modifications of the various embodiments shown and described herein may be made without departing from the spirit and scope of the invention. Accordingly, it is intended that the invention be limited only to the extent required by the appended claims and the applicable rules of law.
REFERENCES
American Concrete Institute (ACI) Committee 318 . “ACI 318-11 : Building code requirements for Structural Concrete .” ACI Standard, 2011.
Barkdoll, B. D., Ettema, R., and B. W. Melville, Countermeasures to Protect Bridge Abutments from Scour , NCHRP Report 587, pp. 1-3, 2007.
Ettema, R., Yoon, Byungman, Nakato, Tatsuaki and Muste, Marian, A review of scour conditions and scour - estimation difficulties for bridge abutments , KSCE Journal of Civil Engineering, Volume 8, Number 6, Pages 643-65, 2004.
Lagasse, P., Zevenbergen, L., Schall, J., and Clopper, P., Bridge Scour and Stream Instability Countermeasures . FHWA Technical Report Hydraulic Engineering Circular (HEC)-23, (3.10˜11 pages 66-67), 2001.
Hunt, B., Monitoring Scour Critical Bridges , NCHRP Synthesis 396, pages 1-2, 2009.
Richardson, E. V. and Davies, S. R. Evaluating scour at bridges . FHWA NHI 01-001 HEC-18, Federal Highway Administration, US DOT, Washington, D.C., section 1.1, 2001.
Sheppard, D. M., Demir, H., and Melville, B., Scour at Wide Piers and Long Skewed Piers , NCHRP-Report 682, page 26, 2011.
Simpson, R. L., Full - Scale Prototype Testing and Manufacturing and Installation Plans for New Scour - Vortex - Prevention scAUR™ and VorGAUR™ Products for a Representative Scour - critical Bridge , NCHRP-IDEA Report 162, 2013.
Simpson, R. L., Junction Flows , Annual Review of Fluid Mechanics, Vol. 33, pp. 415-443, 2001.
Tian, Q. Q., Simpson, R. L., and Lowe, K. T., A laser - based optical approach for measuring scour depth around hydraulic structures, 5 th International Conference on Scour and Erosion, ASCE, San Francisco, Nov. 7-11, 2010. | Several practical refinements, extensions, additions, and improvements to the manufactured three-dimensional continuous convex-concave fairing with attached vortex generators are provided. The piecewise continuously varying slope and curvature fairings provide manufacturing cost reductions, as well as cost reductions by reducing the frequency and complexity of monitoring practices for bridges and elimination of temporary fixes that require costly annual or periodic engineering studies and construction to mitigate scour on at-risk bridges. The probability of bridge failure and its associated liability to the public is totally avoided since the root cause of local scour is prevented. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention is in the technical field of Medicine. More particularly, the present invention is in the technical field of medicine where there is need to gain access to target location, body cavity or vessel lumen by inserting a needle. Currently one of the more common ways to gain access to target location is to insert needle in the body. Those needles could be sharp or blunt ended based on the target location and purpose of use. It is a very common practice to use a needle system with cannula and stylet (Wiley, 2012) or one with a side aperture. (Richard Kulkashi, 1992) Upon insertion to desired area, the stylet is removed and location confirmed by either the flow of desired fluid (e.g. spinal fluid in spinal cord placement, pleural fluid in pleural placement, blood in vascular placement) or injecting contrast or similar material (e.g. contrast injection in peritoneal cavity to confirm peritoneal placement) into the needle port.
[0002] This process of placing the needle at target site is followed by the objective of carrying out the procedure e.g. collect samples (spinal fluid, pleural fluid) or inject drugs (peritoneal space) or pass a wire to secure the access to location (in blood vessels or other body cavities). Most of the current needles in market have openings at the end (e.g. Hawkins needle) which, after removal of the stylet could injure the underlying organs (e.g. due to unexpected movements by operator as connecting/disconnecting syringe or movements by patient subject as with breathing or coughing). There are also needles currently available in market with side opening but they do not allow passage and withdrawal of wire through the side openings as they have sharp edges on side openings or are angled which is not ideal for movement of wire in and out of needle. (Walter A. Z0hmann, 2003; Peter John Crocker, 2005; Johnson, 1987)
[0003] The above-described needles are far from ideal. Generally speaking the following steps involved using current needle design with cannula during needle placement to target location: a) insertion of needle into tissue, b) removal of stylet, c) attachment of syringe to needle port, d) injection of contrast/aspiration of fluid thru the port to confirm location, e) detachment of syringe from port, f) insertion of desired wire thru port to gain and secure access to target location, and g) removal of needle over the wire, leaving one end of the wire securely at target location. Performing these multiple steps has its own limitations, namely: a) longer the procedure time as multiple steps are need to be performed (removing stylet, hooking/unhooking syringes), b) Increase risk of procedure complications (organ/vessel perforation/injury) due to risk of needle movement while performing any of the above steps or movement by patient, c) complications arising while removing wire from the needle due to wire getting stuck in needle or breaking inside the patient's body due to wire getting caught because of direction of needle aperture, d) increased complexity of the procedure as multiple discrete steps needs to be followed sequentially, and, e) increased chances of error due to increased complexity (e.g. injection of medicine instead of contrast to confirm location, insertion of wire without confirming location while needle is not in right location etc.) Using a Veress needle in an above described method to gain access to peritoneal sac, there is a 15% first pass failure rate, 0.3% morbidity rate, and 0.07% mortality rate, principally from either failing to fully penetrate into the peritoneum or puncturing vital organs and vessels. (U.S. Pat. No. 8,608,697 B2, 2013)
[0004] Previously needles have been described which use stylet, where the stylet has to be removed after insertion. (Young, 1982; Anderson, 1991; Teves, 1988). These needle designs would cause problems as once the stylet is removed, the pointed hollow needle tip would rest on the tissue. During the process of attaching/detaching syringe or movement by operator or patient, the pointed hollow needle tip could lead to complications, including damage to the tissue or organs around the needle tip.
[0005] Another type of needle (Johnson, 1987) has also been described with side aperture and blunt tip. This needle would provide the needed blunt end but would not facilitate passage of wire or similar structure to and from the needle lumen due to the angle or the aperture or wire being caught in the aperture. Even when those holes are created towards the end of the needle, their deflection angle is not conducive enough to permit smooth passage of wire. Given that those holes are punched onto the lateral surface of the needle, it would potentially lead to the wire getting catch on it and/or break it, further leading to another complication for its use.
[0006] This invention seeks to provide an improved type of tissue needle by allowing the two primary functions of the needle (i.e. tissue penetration and fluid transfer) while also allowing passage of wire and hence simplifying the entire process of needle insertion and gaining access to target location without the disadvantages and compromises forced by existing needle designs.
SUMMARY
[0007] The present invention addresses the above and other needs by providing a needle having no stylet, a side aperture at the insertion end, and which permits transfer of fluid, gas and substances like wire thru it, all by simplifying and reducing the multiple steps of the overall procedure as described above.
[0008] In one embodiment of the needle, the needle body has a blunt end with side aperture partially covering the tip, designed and directed in a way that it would permit the passage and withdrawal of wire from the needle. The location of the aperture to partially cover the tip would also be conducive to remove needle over the wire without the distal end of needle getting stuck in tissue upon withdrawal of needle. The needle could also have a solid body at the needle tip portion after last aperture so that it facilitates movement of wire in and out of the aperture and not letting the wire getting caught within the needle conduit portion whereby the margins of the aperture are smoothened.
[0009] In one embodiment, the needle has two ports at the top. One to attach a syringe and other to possibly run a wire once the position of the needle tip portion is confirmed at target location without the need to detach the syringe at the first port. It is thus a feature of the present invention to provide a needle which has the composite properties of reducing the time and complexity of doing the procedure and provide better stability and functionality to the needle system and potentially simplifying the process and reducing the complications.
[0010] It is yet another feature of the present invention to provide a needle which can be used in combination with a wire which may be inserted and rapidly deployed to secure access to the target location such that the side aperture has two sections connected to two different ports respectively and each connected to a syringe and a wire respectively so that upon insertion, the syringe can be used to confirm the locations of needle tip followed by deployment of the wire.
[0011] In many embodiments, the distal tip of the needle comprises a tapered profile, and the distal tip of the needle may comprise an atraumatic needle tip.
[0012] In some embodiments, the needle may comprise indicia over the proximal portion thereof. The indicia may indicate the position of the distal end of the needle relative to the marks. The indicia may comprise a scale form printed or etched on a surface of the needle. In specific embodiments, the indicia may comprise a color change on the needle.
[0013] In one embodiment of the needle, the needle body has a blunt end with side aperture just proximal to the tip, designed and directed in a way that it would permit the passage and withdrawal of wire from the needle. The location of the aperture to be just proximal to the tip would be conducive to create just enough space by the needle tip being pushing the tissue, so as to allow for the passage of the wire. The needle could also have a solid body at the needle tip portion after last aperture so that it facilitates movement of wire in and out of the aperture and not letting the wire getting caught within the needle conduit or aperture portion, whereby the margins of the aperture are smoothened.
[0014] In some embodiments, the needle may have a stylet placed from one port while a syringe attached to another port, while both are connected to the common conduit area whereby as soon as needle is placed, the stylet removed from first port and location confirmed by injection of contrast in second port followed by insertion of wire in the first port to secure location at target tissue location.
[0015] In specific embodiments, at least the needle or various components of the needle may comprise of tungsten, rhenium, tantalum, palladium, tungsten-carbide, stainless steel, molybdenum-rhenium, molybdenum or cobalt-chromium.
[0016] Thus, the present invention provides an improved needle which can be used advantageously in multiple different procedures where access to tissue, vessel lumen or cavity is needed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings, wherein:
[0018] FIG. 1 shows, in accordance with the present invention, the system comprising the needle in a front elevation view.
[0019] FIG. 2 shows a right side elevation view of the needle illustrated in FIG. 1 ;
[0020] FIG. 3 is a left side elevation view of needle illustrated in FIG. 1 ;
[0021] FIG. 4 is a section taken generally along line C-C thereof in FIG. 1 ;
[0022] FIG. 5 a is a section taken generally along line A-A in FIG. 1 ;
[0023] FIG. 5 b is a section taken generally along line A-A in FIG. 1 also representing the movement of wire within the needle
[0024] FIG. 5 c is a section taken generally along line A-A in FIG. 1 depicting the angle of the direction of the aperture opening.
[0025] FIG. 6 is a tip view (view from the needle tip where the longitudinal axis of the needle body projects into and behind the page) of the needle illustrated in FIG. 1
[0026] FIG. 7 is the detailed view ‘B’ of the needle tip illustrated in FIG. 1
[0027] FIG. 8 shows another embodiment of invention of FIG. 1
[0028] While invention will be described in connection with a certain preferred embodiment, it will be understood that it is not intended to limit this invention to that particular embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0029] The following description is of the best mode presently contemplated for carrying out invention's work. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of the current embodiment. The present invention provides, in one aspect, an improved needle that may be used in various applications such as abdominal cavity insertion or lumbar puncture. It will be appreciated by those skilled in the art that the needle of the present invention is not limited to aforementioned applications but may be used for other applications that utilizes needle, such as, for example, pleural fluid tapping.
[0030] One version of the invention is better understood, with reference to the figures. Turning now to the drawings, FIGS. 1, 2 and 3 show various external views of the needle, generally designated 10 , in accordance with the present invention FIG. 1 shows a perspective front view of an embodiment of a three-dimensional form of a needle comprising of a tip portion ( 20 ) incorporating at least a tip ( 21 ), at least one aperture ( 22 ), conduit portion ( 30 ) incorporating at least one barrel section ( 32 ) in fluid communication ( 31 ) with the aperture ( 22 ) on one end and one or more port ( 40 ) on the other end. The lateral aperture ( 22 ) is designed and placed towards the tip ( 21 ) so as to help with the passage of wire as described below. The needle being relatively solid and strong while it could provide a rounded atraumatic point ( 21 ) to prevent organ damage.
[0031] The needle is suitable for use in many types of applications involving the transfer of fluids, gases or a combination thereof or inserting wire to secure access to target location. Such substances may be liquids or gases, including solutions, colloids, and suspensions of particulate matter in fluids or gases or materials like wire, polymers or a combination of above. The advantageous properties of the needle in construction and composition that make it strong but relatively atraumatic in use, causing less damage to the tissue it penetrates, make it suitable for transferring fluids to and from bodies, or run wires to and from bodies, as well as many other applications that will become evident to a broad range of users.
[0032] Gaseous, fluidic or solid materials are transferred from port ( 40 ) through the conduit portion ( 31 ) which in turn is connected to the aperture ( 22 ) and vice versa. It will be understood that one of more port ( 40 ) may act as an inlet or outlet for material, which may move in either direction through the conduit portion ( 31 ). Referring now to FIG. 4 , it shows a cross section view at point C-C of the needle 10 as shown in FIG. 1 . The cross section comprises of the conduit portion ( 31 ) and barrel section ( 32 ). It will be understood that the conduit may take other embodiments, such as being comprised of more than one passage. Multiple passages may be concentrically disposed of side-by-side.
[0033] In use, the needle penetrates the skin and tissue which seals on the barrel ( 32 ) above the aperture, as it passes through it. When the needle has penetrated to the target location the fluid is injected into the conduit portion ( 31 ) via port or substance seen flowing out of the port ( 40 ) to confirm location. The fluid or air could also be sucked out of the target location by applying negative pressure at the port ( 40 ).
[0034] Referring now to FIGS. 5 a , 6 and 7 , these show a side view, point view and a front view respectively, of an embodiment of needle tip portion ( 20 ) which can be made of metal or a suitable plastics or polymer or an alloy or a combination of such materials, and comprises a needle tip ( 21 ) and an aperture ( 22 ) close to it. The needle tip ( 21 ) can be blunt or sharp. In use, the needle tip ( 21 ) penetrates the skin and there is preferably a minimum tissue cutting and displacement by the needle ( 10 ) itself. In use the small hole formed in skin and tissue by the tip ( 21 ) is smoothly extended along the path and elongate section with minimum of sharp edges or sharp changes in direction to catch or snag tissue. The needle tip portion ( 20 ) can be made of one or more different materials where the separate parts are joined together. The rounded end tip ( 21 ) is a surprisingly efficient means of atraumatic insertion and opening up tissue as the needle tip ( 21 ) penetrates the tissue. Preferably the needle comprises of a blunt point at a distal end as illustrated herein. However, the scope of the Invention includes that the distal end includes alternative shapes (e.g. sharp or pointed based on desired use) depending on the intended use.
[0035] Referring now to FIGS. 5A, 5B and 5C , there shows a plan side view of an embodiment of needle tip portion ( 20 ) which comprises a needle tip ( 21 ) and an aperture ( 22 ) formed in it. The aperture is placed and angled in such a way that when a wire or similar structure is passed into the conduit portion ( 31 ) it would facilitate the passage of wire through the aperture ( 22 ). The same aperture shape and angle would also help facilitate the removal of the wire from the aperture ( 22 ) and conduit ( 31 ) without getting the wire caught or kinked by the aperture edges ( 23 ) or direction of aperture opening (Angle E). Generally the conduit portion ( 31 ) leading up to the aperture ( 22 ) is angled (Angle E) at more than 110 degree angle to the axis of the needle to facilitate the movement of wire or similar structure without getting it kinked or caught on the aperture edges ( 23 ). The position of the aperture ( 22 ) closer to the needle tip ( 21 ) would also facilitate the removal of the needle over the wire without the distal end of the needle after the last aperture getting stuck in tissue upon withdrawal of needle. It will be understood that the aperture ( 22 ) may take other embodiments, such as being more than one aperture on the needle end and multiple apertures may be disposed concentrically or side-by-side.
[0036] Referring now to FIG. 6 , shows a view from the end point ( 20 ) of the needle tip ( 21 ) perpendicular to the side view in FIG. 2 . From the viewer's perspective the longitudinal axis of the needle tip projects into and behind the page. This figure captures the idea that the aperture ( 22 ) is placed closer to the needle tip ( 21 ) so that it partially includes the tip so that upon tissue penetration still rendering the needle atraumatic while facilitating the exit of wire very close to the tip portion which is in line with the current longitudinal axis of the needle.
[0037] Referring now to FIG. 8 , shows a plan view of a further embodiment of a three-dimensional form of the invention and in which there is a needle tip portion ( 20 ) incorporating at least a needle end ( 21 ), at least one aperture ( 22 ) for substance transfer, conduit portion ( 30 ) incorporating at least one barrel section ( 32 ) in fluid communication ( 31 ) with aperture ( 22 ) on one end and diverging into two barrel sections ( 32 a and 32 b ) leading to their respective ports ( 40 a and 40 b ) on the other end. The syringe can be mounted through one port ( 40 a ) and a wire or similar material passed thru another port ( 40 b ). Such an embodiment would permit passage of wire thru port ( 40 b ) to the conduit portion ( 31 ) to the aperture ( 22 ) as soon as the aperture ( 22 ) location is confirmed at target location by injection of contrast material or fluid or flow of fluid through port ( 40 a ) without the need to disconnect the syringe from the first port ( 40 a ).
[0038] Preferably the needle is comprised of a stainless steel or polymeric material. The needle may need reinforcement component that can be made of materials such as stainless steel, tungsten, elgiloy, platinum molybdenum, iridium or nitinol and/or other metals. It could also comprise alloys, e.g. platinum-iridium, molybdenum-rhenium, tungsten-rhenium, platinum-tungsten and/or other alloys. The materials could also be polymers such as Kevlar, Dacron, PEEK and/or other polymers. The needle can also comprise of at least one separate component made of one or more different materials and which the separate parts are joined together and made of different materials as mentioned above. Preferably the material is suitable for injection molding or compression molding of any type, for example fluid-assisted molding, two-shot molding, thermoplastic or thermosetting molding. The needle can be made by process steps comprising closing the tip of needle ( 20 ), forming a primary angle onto tip porting ( 20 ), processing by mechanical or chemical means to shape and smoothen the conduit portion ( 31 ) leading up to the aperture ( 22 ) and the edges of the tip and all apertures. Preferably the process includes the steps of providing a surface to reduce friction and/or retain lubricant at the surface. It can include using laser welding the different parts of the needle.
[0039] In some embodiments, the needle could comprise of polymer, with or without, a metal stylet to provide inner strength, while being less brittle and being less traumatic to the penetrated tissue. Such polymer needle would also require more cycles and/or force to break than a stainless steel needle. Also, known injection molding or folding techniques can make the polymer needle easier to manufacture.
[0040] The scope of the invention is not limited to having a single port and aperture in a needle tip as shown in FIGS. 1 thru 3 . Other embodiments are within the scope, including one shown in FIG. 8 . The scope of the invention includes that even further embodiments that are not illustrated in this document, including a plurality of apertures and a plurality of ports with various combinations of connections.
[0041] For many uses the needle has a length of 2 to 200 mm. The needle can be used with any injection device such as a syringe, pen, etc. and the length of the needle is chosen for the application of the needle. Examples of use are to add or remove substance during procedures including paracentesis, pleurocentesis, and lumbar puncture, gaining access to any body cavities like abdomen, pleural, spinal or into any blood vessels. It would also include but not limited to sub-cutaneous, intra-muscular, intra-venous, into bone, into joint, into eye, into any organ, and for any tissue penetration. The needle can also be used to add or remove substance for medicinal or diagnostic or other purposes for human or animal or other applications.
[0042] While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.
[0043] In broad embodiment, the present invention is that of a needle ( 10 ) suitable for use in many types of applications comprising of a needle tip portion ( 20 ), a barrel portion ( 30 ) and the port portion ( 40 ). Such a needle would benefit by providing atraumatic insertion while also facilitating insertion and removal of fluids and gases and more importantly allowing passage of wire and similar structure and thus simplifying the entire process of gaining access to target location, reducing the overall time needed to perform the procedures (as fewer steps involved) and reducing chances of complications and error by reducing and simplifying the steps involved.
[0044] While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The invention should therefore not be limited by the above described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention.
REFERENCES
[0000]
Anderson, R. W. (1991, May 28). U.S. Pat. No. 5,019,039.
Johnson, G. W. (1987, Dec. 1). U.S. Pat. No. 4,710,180 A.
Pelu Tran, K. T. (2013, Dec. 17). U.S. Pat. No. 8,608,697 B2.
Peter John Crocker, M. A. (2005, Aug. 11). U.S. Pat. No. 0,177,117 A1.
Richard Kulkashi, M. P. (1992, Mar. 24). U.S. Pat. No. 5,098,388.
Teves, L. Y. (1988, Jan. 26). U.S. Pat. No. 4,721,506.
Walter A. Z0hmann. (2003, May 6). U.S. Pat. No. 6,558,353 B2.
Wiley, C. W. (2012, May 8). U.S. Pat. No. 8,172,802 B2.
Young, R. (1982, Jan. 5). U.S. Pat. No. 4,308,875. | A needle suitable for use by inserting thru tissue for gaining access to target location. A needle is provided which has improved functionality and reducing complexity of procedure. The needle is comprised of an end with side aperture towards the tip portion, which is connected via conduit portion to the needle port. In one embodiment, the needle is comprised of a hollow needle with a port and a distal atraumatic end towards which there is a single aperture on the side wall, wherein a wire can be moved within the needle without damaging the wire. In other embodiment, the needle is comprised of a hollow needle with more than one port connected to tip portion towards which there are multiple apertures on the side wall, wherein a contrast or fluid injected from one port and wire can be inserted and removed from another port of the needle. | 0 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates in general to sewing machines, and in particular to a new and useful material feed device for sewing machines which includes upper and lower feed dogs, a presser foot, and means for adjusting the movements of the feed dogs and the pressure of the presser foot.
A machine is disclosed in U.S. Pat. No. 3,808,995, that is intended for sewing together sections of clothing in which, in addition to ungathered seam segments, the differential puckering or gathering of an armhole, for example, required to fit a sleeve into a finished article of clothing is also produced in the different segments of the circumference of the sleeve, in other words, ungathered seam segments alternate with seam segments with differing degrees of gather. The differential feed values can be predetermined by corresponding adjustment of the stitch guide for the size of the feed motion of the feed dog. All seam segments are sewn by this sewing machine with the same contact pressure of the presser foot adjusted to an average value based on experiential values.
Although it is known in the trade that with certain types of sewing work the best results can be obtained only with just the right pressure by the presser foot, e.g., gathered sewing must be done at very low pressure, while during ungathered segments a considerable heavier pressure is required, with conventional machines no arrangements have been made to adapt the contact pressure to the given type of sewing operation.
U.S. Pat. No. 2,544,029 does disclose a presser foot control device in which, besides a toggle lever bar operable by the usual toggle lever for reducing the contact pressure and raising the presser foot from the material, a second toggle lever, operable counter to the first toggle lever, is provided on the toggle lever bar by means of which and as needed, when sewing over cross-seams, for example, the angle position of an eccentric supporting the presser bar spring can be changed and the pressure of the presser foot thus be increased and then subsequently reduced again. The alteration and selection of the right contact pressure, however, in each case is left up to the skill and flair of the seamstress, who cannot be expected to find precisely the right adjustment required in each case repeatedly and in alternation. The operating results therefore vary a great deal.
SUMMARY OF THE INVENTION
The object of the present invention is to equip a sewing machine with a differential feed such that first of all, the feed-in of excess material can be executed with reduced contact pressure by the presser foot, the evenness of the gathers being thus improved, such that the material to be gathered is subjected merely to a negligible braking effect by the presser foot, and in the second place, that simultaneously with the adjustment for synchronization of the feed motion of the feed dogs, the contact pressure can be increased for sewing together the sections of clothing without displacement and for gathering and for securely "fastening" the end of the seam.
Accordingly an object of the present invention is to provide a material feed device for a sewing machine which comprises an upper and a lower feed dog, stitch guide means operatively connected to the feed dogs for adjusting their feed motions, adjusting means connected to the stitch guide means for controlling the stitch guide means to change the adjustment of the feed dog motions, a presser foot mounted for engagement against the lower feed dog, first pressure means operatively connected to the presser foot for pressing the presser foot against the lower feed dog, and second pressure means operatively connected to the presser foot and to the adjusting means for exerting additional pressure on the lower feed dog which is dependent on the feed motion of the feed dogs produced by control of the adjusting means.
A further object of the present invention is to form the adjusting means as a control cam which is operatively engageable with an air valve that operates in synchronism with the adjustment of movement for the feed motions, the control cam being rotatable to control the second pressure means.
A still further object of the invention is to mount the control cam at an adjustable angle on the adjusting means, the adjusting means comprising a rotatable disc for one of the feed dogs.
This makes it possible to coordinate precisely the operation of the air valve and the adjustment of the one stitch guide with each other.
A still further object of the invention is to provide a material feed device for a sewing machine which is simple in design, rugged in construction and economical to manufacture.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings
FIG. 1 is a diagrammatic, simplified depiction of a sewing machine with an upper and a lower feed dog, adjustable independently of one another, with a device for controlling one stitch guide and an extra pressure device;
FIG. 2 is a diagrammatic depiction of the feed dog and presser foot mechanism in disassembled condition; and
FIG. 3 is a pneumatic switching diagram for the extra pressure device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The sewing machine indicated by dash-dotted lines and designated 1 in FIG. 1 is an overcast sewing machine with an upper feed dog 2 and a lower feed dog 3. The lower feed dog 3 is adjustable to an average value of its feed stroke and the upper feed dog 2 is adjustable to a greater need motion by a device to be described below. Referring to FIGS. 1 and 2, the upper feed dog 2 is attached to a support bar 5 by a screw 4. A crank pin 6 of a swing shaft 7 extends through a hole in the opposite end of the support bar 5 of the upper feed dog 2. The connection is secured against axial movement by a spring clip 8.
The swing shaft 7 leads through a hole in a bearing lug 10 projecting from an adjusting level 11 and turnable within a bearing sleeve 9 and a slotted boss 12 on a forked lever 13. A crank 14 is clamped on the end of the swing shaft 7 by a screw 15. The forked lever 13 is clamped on the bearing lug 10 of the adjusting lever 11 by a screw 16. In the crank 14 is mounted a crank pin 17 that is connected by a connecting rod 18 to the link pin 19 of a slide guide 20. The connecting rod 18 is secured against axial movement on the pins 17 and 19 in each case by a spring clip 21.
In a groove 22 in the slide guide 20, a curved guide 24 which is attached to a swing shaft 23, moves. The curved guide 24 has a lever arm 25 that is linked to an eccentric bar 26, whose other end surrounds an eccentric 28 attached to a drive shaft 27.
To shift the slide guide 20 on the curved guide 24 and hence to change the feed motion of the upper feed dog 2, a cover plate 29 is screwed onto the slide guide 20 with screws 30, the cover plate 29 having a bearing pin 31 for a slide block 32 that can move in the guide fork 33 of the fork lever 13 and is secured on the bearing pin 31 by a screw 34 with an intervening washer 35.
As the shaft 27 turns, horizontal feed motions are transmitted to the upper feed dog 2 by this drive connection. Associated with the adjusting bar for the upper feed dog 2 are an extension 37 firmly attached to the adjusting lever 11 by screws 36, onto which extension is screwed a stop screw 42 that passes through a curved slot 38 in a stationary scale plate 39 and secured by a washer 40 and a nut 41, as well as a ball tie rod 44 connected to the free end of the extension 37 via a ball pin 43 and connected to an adjusting disc 46 via a ball pin 45.
In order to transmit the requisite lifting motions to the support bar 5 and hence to the upper feed dog 2, a crank 47 is attached to the oscillating drive shaft 23, a pin 48 being firmly fixed in the free end of the crank 47 and reaching under the support bar 5. In order to dampen noise, the bent free end of a leaf spring 49 screwed to the underside of the support bar lies against the pin 48.
By means of these drive connections, the upper feed dog performs elliptical operating motions.
The support bar 5 with the upper feed dog 2 is pressed downwardly with an adjustable pressure by a compression spring 50. The compression spring 50 is mounted on a presser bar 52 capable of shifting within a housing 51 and having on its lower end a press roller 53 that can turn around a peg 54 and rests on the support bar 5. The compressed length of the compression spring 50 can be changed by means of an adjusting screw 55 that screws into the housing 51 in order to change the force of the spring. The adjusting screw 55 can be locked by means of a knurled nut 56.
The upper feed dog 2 and the lower feed dog 3 work together to move the material by means of a toothed grip. Feed dog 3 is attached by means of a screw 57 to the free end of a support bar 58 that is linked at its other end to a crank 60 attached to a shaft 59 subject to an oscillating drive. By means of this drive connection, horizontal feed motions are transmitted to the support bar 58 and the lower feed dog 3.
An eccentric 63 extends into a forked opening 61 on the support bar 58. Eccentric 63 is attached to a rotating shaft 62, whereby the customary lifting motions are communicated to the support bar 58 and the lower feed dog 3. A combination of the feed and lift motions results in elliptical operating motions of the feed dog 3.
The presser foot 64, whose sole 65 has a slot 66 to allow the upper feed dog 2 to pass through, serves to press the material against the lower feed dog 3. The sole 65 is linked to a shank 67 that grips onto a pin 68 on the presser foot support 69. The presser foot support 69 can pivot around a link pin 70 in a mounting 72 attached to a shaft 71. In addition to the mounting lever 72, a lever 73 is clamped onto the shaft 71, the lever having a pin 74 on its free end that reaches under the support bar 5 of the upper feed dog 2. When the shaft 71 turns, the upper feed dog 2 and the presser foot 64 are raised.
In a fashion similar to that in which the upper feed dog 2 is pressed downwards with an adjustable contact pressure by the pressure device 50 through 56, the presser foot 64 is also acted on by another pressure device, labelled with the same reference numbers for the sake of simplicity.
In addition to this pressure device, the presser foot 64 is provided with an extra pressure device in the form of a single acting pneumatic cylinder 75, whose working piston 76 can be actuated counter to the action of a compression spring 77. The piston rod 78 connected to the working piston 76 bears a fork head 79 that is linked to an angle plate 80 on the presser foot support 69.
To control the pneumatic cylinder 75, a control cam 82 with two screws 84 guided in curved longitudinal slots 83 in the control cam 82 is mounted at an adjustable angle on the adjusting disc 46 turnably mounted on a stationary supporting angle plate 81. When the adjusting disc 46 is in a given angular position, the switching lever 85 of a 2/2-way air valve 86 is activated by the control cam 82. The valve is thus moved oounter to the action of a restoring spring 87 (FIG. 3) from a switching position "0" to a switching position "1", so that the air coming from a pressure source 88 flows through the lines 89 and 90 hooked into this switching position of the valve 86, to the pneumatic cylinder 75, whose working piston 76 and hence the presser foot support 69 via the piston rod 78, the forked head 79 and the angle plate 80 are subjected to additional pressure.
The adjusting disc 46, which is connected to an indicator 91 of the actual angle for the disc, is driven by an electric motor 92 which receives its control order following a request by actuation of the keys of a selection device 93 with a keyboard of a control device 94. The selection device is connected by one line 95 to the actual value indicator 91 and by another line 96 to the control device 94, which is in turn connected by one line 97 to the actual value indicator 91 and by another line 98 with the electric motor 92.
For gathered sewing, a separating plate 99 that can be introduced between the layers of material to be sewn is provided that is mounted on a support arm 100 that is supported on a bearing piece 101 fixed to the sewing machine housing, the arm being capable of pivoting around a link pin 102.
The sewing maching works as follows:
Since the sewing machine is primarily used for gathered sewing, the contact pressure of the presser foot 64 is so far reduced at the adjusting screw 55 for the spring 50 that the upper layer of material to be gathered is subject only to a negligible braking effect by the presser foot 64.
In preparation for the sewing process, the separating plate 99 is pivoted away to the side, the upper feed dog 2 and the presser foot 64 are raised by turning the shaft 71 with the associated presser foot support 69 and the lever 73 whose pin 74 reaches under the support bar 5, the layers of marerial to be sewn are positioned, and the separating plate 99 is pivoted in between the layers of material, when the upper layer of material is supposed to be gathered and then sewn together with the lower layer of material.
The feed motion of the lower feed dog 3 is adjusted for this purpose with the aid of a conventional stitch guide, to a constant median value, in contrast to which the upper feed dog 2 can be adjusted by pressing keys "1" through "9" of the selection device 93 to perform nine increasingly larger feed motions. By these means, adjustments for nine different degrees of gathering are available. By pressing key "0", synchronous adjustment of the feed motions of both feed dogs 2 and 3 is accomplished. This is the case when the layers of material are to be sewn together without gathers. Whichever of the ten available adjustments is selected at any given time is indicated on a lighted display on the selection device 93.
The selected switching pulse of keys "0" through "9", e.g. "9", brings about via the control device 94, a preparatory adjustment of the actual value indicator 91 and the start-up of the electric motor 92, which turns the adjusting disc 46 to an angle corresponding to the selected positon "9". As soon as that angle position is reached, the actual value indicated 91 gives a signal to the control device 94, and the electric motor 92 is shut off.
When the adjusting disc 46 is turned, it also turns, via the ball tie rod 44 and the extension 37, the adjusting lever 11 and with it the bearing lug 10 on which the forked lever 13 is mounted. Via the forked lever 13 and the slide block 32 the slide guide 20 is then moved along the curved guide 24 into a position that corresponds to the feed motion of the upper feed dog 2 requested by pressing key "9". As is state of the art with such sliding stitch guides, the size of the feed motion communicated to the feed dog is dependent on the distance of the slide guide 20 along the curved guide 24 from the shaft 23 on which curved guide 24 driven by the rotating shaft 27 by means of the eccentric 28 via the eccentric rod 26 in an oscillating drive is mounted.
Now that the sewing machine 1 has been switched on, the swinging motion communicated by the curved guide 24 is transmitted via the link pin 19 of the slide guide 20, the connecting rod 18 and the crank pin 17 to the crank 14 and hence to the swinging shaft 7. The motion is then transmitted as horizontal feed motions via the crank pin 6 to the support bar 5 and hence to the upper feed dog 2. The size of those motions, as already said, is greater than the mean value of the feed motions communicated to the lower feed dog 3 by the swing shaft 59 via the crank 60 of its support bar 58, so that a given excess of the upper layer of material is moved forward and a given degree of gather is thus created.
In addition to the feed motions, the requisite lift motions are communicated to the lower feed dog 3 by the eccentric 63 on the shaft 62 and to the upper feed dog 2 via the crank 47 on the swing shaft 23 and the pin 48 that reaches under the support bar 5.
The degree of gather in the upper layer of material can be changed at any time the machine is at rest by pressing one of keys "1" through "9" on the selection device 93. The slide guide 20 is then shifted by the electric motor 92 via the adjusting disc 46 as described above into another position on the curved guide 24, whereupon the size of the feed motion communicated to the upper feed dog 2 is changed.
Since all gathered sewing is performed with very low pressure by the presser foot 64, the amount of excess material called for can be more precisely controlled, and the gathers come out more even.
In order to sew together the layers of material without shifting gathering during certain seam segments, for which purpose much stronger pressure by the presser foot 64 is required, and the separating plate 99 is pivoted out to the side, the ungathered segments being usually marked when the material is cut out, as are the gathered segments as well, the synchronous adjustment of the feed motions of both feed dogs 2 and 3 is started by pressing the "0" key on the selection device 93. The adjusting disc 46 is thereupon turned by the electric motor 92 so that in the requisite adjustment of the slide guide 20 along the curved guide 24 the control cam 92 on the adjusting disc 46 presses down the switching lever 85 of the air valve and the air valve 86 thereupon moves from the locked-void position "0" to the flow-through switching position "1". In the flow-through switching position "1" the working piston 76 of the pneumatic cylinder 75 is subjected via lines 89 and 90 to pressurized air. This has the effect that the presser foot 64 is pressed downwardly with extra pressing force via the piston rod 74 acting on the presser foot support 69. By increasing the pressure acting on the presser foot, shifting of the layers of material with respect to one another is effectively prevented, and empty stitching when the material passes out of the stitching location is better controlled.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | A sewing machine with adjustable upper and lower feed dogs is for sewing together sections of clothing in which ungathered segments of seams alternate with seam segments with differing degrees of gather. The spring-held presser foot is coordinated with a pneumatic cylinder as an additional mechanism of increasing contact pressure during the sewing of ungathered segments of seams. The cylinder is operable by a control cam connected to an adjusting mechanism for a stitch guide of one of the feed dogs. When sewing gathered segments, the pressure of the presser foot is greatly reduced, whereas the pressure is increased during the sewing of gathered seam segments and through a "fastening" step at the end of the seam. | 3 |
FIELD OF THE INVENTION
[0001] The present application relates generally to the use of home audio video display devices (AVDD) such as TVs as sensor monitors.
BACKGROUND OF THE INVENTION
[0002] Current sensors, such as household environmental sensors, light sensors, and motion sensors, typically have individual displays associated with each sensor to display data from each sensor. Present principles recognize that the displays are often small and/or low-quality, making the displays difficult to read, understand, and ascertain useful information from, among other things.
[0003] Also understood herein, the displays are typically positioned in close proximity to its respective sensor such that multiple displays associated with different sensors are often not located in the same general location of, e.g., a personal residence. Thus, a need has arisen to aggregate the information produced by one or more sensors in a single location for convenient viewing, rather than requiring multiple displays scattered in different locations to the display data and/or information and thereby making monitoring of the data and/or information from the sensors burdensome.
SUMMARY OF THE INVENTION
[0004] An audio video display device (AVDD) system includes a display and a processor controlling the display. The AVDD also includes a computer readable storage medium accessible to the processor and programmed with instructions that cause the processor to establish communication with at least one sensor. The instructions also cause the processor to receive information from the sensor conforming to an application programming interface (API) provided by a manufacturer of the AVDD to an entity affiliated with the sensor, or sent from the AVDD to the sensor and then present the information from the sensor on the display in accordance with the API.
[0005] If desired, the API can define, relative to the information from the sensor, content in the information from the sensor to be presented on the display, where the content is to be presented on the display, and when the content is to be presented on the display. As indicated above, in some embodiments the API may be provided by a manufacturer of the AVDD to an entity affiliated with the sensor, while in other embodiments API may be sent from the AVDD to the sensor. Even further, in some embodiments the API is sent from the AVDD to the sensor only in response to a viewer-input command.
[0006] In accordance with present principles, the sensors may be selected, though not required to be exclusively selected, from a group of sensors consisting of environmental sensors, ambient light sensors, door position sensors, window covering position sensors, pool heater energization sensors, motion sensors, and valve position sensors. Though present principles are described in reference to a personal residential environment, it is to be understood that the same principles may be applied to sensors and monitoring equipment in, e.g., a hospital or a public security environment as well.
[0007] If desired, the content can include alpha-numeric information only, an icon only, or both an icon and alpha-numeric information. Moreover, in some embodiments the system also includes the sensor. The sensor includes a processor accessing the API and sending the information to the AVDD in accordance with the API.
[0008] In another aspect, a method includes establishing communication between an audio video display device (AVDD) including a display and at least one sensor. The method then includes receiving information from the sensor(s) conforming to an application programming interface (API) provided by a manufacturer of the AVDD to an entity affiliated with the sensor(s), or sent from the AVDD to the sensor(s). According to the method, the information from the sensor(s) is then presented on the display in accordance with the API.
[0009] In yet another aspect, an audio video display device includes a display and a processor controlling the display. The device also includes a computer readable storage medium accessible to the processor and programmed with instructions that cause the processor to establish communication with at least one sensor. The instructions then cause the processor to receive information from the sensor(s) conforming to a software interface understandable by the AVDD. Thereafter, the instructions cause the processor to present the information from the sensor(s) on the display in accordance with the interface.
[0010] In other aspects, multiple sensors are monitored simultaneously to determine if an event has occurred (e.g., a combination of medical sensors; or home automation sensors indicating sound, movement, etc., that suggests a break in). A system according to present principles may re-send the sensor information to the cloud, to either facilitate processing, or to be made available to a third party for monitoring the sensor data (parents concerned about a child's security, home security company, medical professionals, etc.).
[0011] The details of the present invention, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a block diagram of an example system, showing a home AVDD communicating with several example sensors for presenting information from the sensors on the AVDD;
[0013] FIG. 2 is a flow chart of example logic the AVDD can execute;
[0014] FIG. 3 is a schematic diagram showing the data structure of an example application programming interface (API) that may be pushed by the AVDD to the various sensors automatically when the viewer selects to connect to discovered sensors, or that may be published by a manufacturer of the AVDD to sensor manufacturers so that the sensor manufacturers may pre-program their sensors with the API;
[0015] FIGS. 4-10 illustrate example screen shots from the AVDD presenting example information from various sensors shown in FIG. 1 ;
[0016] FIG. 11 is a block diagram of another example system; and
[0017] FIG. 12 is a flow chart of alternate sensor-driven discovery logic.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] Referring initially to FIG. 1 , a block diagram of an example system including an audio video display device (AVDD) communicating with several example sensors for presenting information from the sensors on the AVDD is shown. It is to be understood that an AVDD in accordance with present principles may be a home AVDD such as, but not limited to, a TV. In some embodiments the TV may further be an Internet TV. Notwithstanding the foregoing, it is to be further understood that still other audio-video display devices may be used in accordance with present principles, such as smart phones, tablet computers, notebook computers, other types of computers, etc.
[0019] Thus, a non-limiting system 10 includes an audio video display device (AVDD) 12 . The AVDD 12 includes a TV tuner 14 that receives TV programming and/or data and/or content for presentation on the AVDD 12 . Further, the TV tuner 14 communicates with a processor 16 accessing a tangible computer readable storage medium 18 such as, but not limited to, disk-based or solid state storage. It is to be understood that the processor 16 can execute logic in accordance with present principles. The AVDD 12 may also include a non-limiting TV signal input 20 allowing the AVDD 12 to connect to, e.g., a television head end, cable communication link, or satellite communication link for receiving TV programming and/or data or content for presentation on the AVDD 12 . Additionally, the AVDD 12 can output audio on one or more speakers 22 .
[0020] Continuing in reference to FIG. 1 , it is to be understood that the AVDD 12 can connect to the Internet using an internet interface 23 such as built-in wired or wireless modem that communicates with the processor 16 to, e.g., send and receive data over the internet “I” or receive streaming video. Without limitation, the Internet interface may be a Wi-Fi interface. Wireless telephony interfaces may also be used. The Internet “I” includes computers, typically servers, and data storage, along with communication switches.
[0021] Regardless of the source of the content, video is presented under control of the processor 16 on a display 24 , such as a high definition TV (HDTV) flat panel display. In some embodiments, the display 24 may be a touch screen display. Also, user commands to the processor 16 may be wirelessly received from a remote commander (RC) 26 using, e.g., RF or infrared.
[0022] The AVDD 12 shown in FIG. 1 also has a sensor communication interface 30 that communicates with the processor 16 to execute the functions and logic in accordance with present principles, among other things. It is to be understood that the sensor communication interface 30 can also establish communication with one or more communication interfaces of respective sensors in accordance with present principles. FIG. 1 therefore shows various exemplary sensors with respective communication interfaces for communicating with the sensor communication interface 30 of the AVDD 12 .
[0023] Thus, an irrigation valve position sensor assembly 32 includes a communication interface 34 that can communicate with the sensor communication interface 30 to send information sensed or gathered or the like by a valve position sensor 36 . Note that while the interfaces 30 , 34 are shown as separate components in addition to the Internet interface 23 , it is to be understood that the communication interfaces between the AVDD 12 and the sensors may be via Internet interfaces such as Wi-Fi interfaces. Or, the interfaces may be short range interfaces such as sonic interfaces, IR interfaces, or Bluetooth interfaces. Thus, information from the sensors herein may be sent to the “cloud” (e.g., Internet “I”) to facilitate processing of the sensor data and then sent back to the AVDD, and/or to facilitate making the data available to a third party for monitoring of the data and providing output signals and alarms to, e.g., wireless computing devices of parents for home/child security, medical professionals, etc.
[0024] The information pertains to the operation and/or status of one or more irrigation valves 38 . The valve position sensor assembly 32 also includes a processor 40 communicating with the communication interface 34 . In non-limiting embodiments, the processor 40 may cause the valve position sensor 36 to sense and/or gather information regarding the operation of the irrigation valves 38 , and/or may receive information from the valve position sensor 36 regarding the operation of the irrigation valves 38 . If desired, the processor 40 may store the information from the valve position sensor 36 on a storage medium 42 . Regardless of whether the information is stored on the storage medium 42 , the processor 40 , being in communication with the communication interface 34 , can provide the information from the valve position sensor 36 to the communication interface 34 and cause the communication interface 34 to send the information to the sensor communication interface 30 of the AVDD 12 so that the AVDD 12 can present the information.
[0025] FIG. 1 also shows a window covering position sensor assembly 44 that includes a window covering position sensor 46 for sensing the position and/or movement of a window covering, a pool heater sensor assembly 48 that includes a pool heater sensor 50 for sensing the status and/or operation of a pool heater and even the temperature of a pool, and a door position sensor assembly 52 that includes a door position sensor 54 for sensing information pertaining to the operation and/or status of a door 60 such as a residential garage door. Also shown in FIG. 1 is an environment sensor assembly 62 that includes an environment sensor 64 for sensing, e.g., the household temperature and humidity of the residence in which the AVDD 12 is disposed. FIG. 1 also includes a motion sensor assembly 66 that includes a motion sensor 68 for sensing motion and a light sensor assembly 70 that includes a light sensor 72 for sensing light.
[0026] It is to be understood that the assemblies 44 , 48 , 52 , 62 , 66 , and 70 include respective processors 74 , 76 , 78 , 80 , 82 , and 84 for causing each assembly's respective sensor to sense, gather, and/or receive information from the respective sensor in accordance with present principles. The respective processors 74 , 76 , 78 , 80 , 82 , and 84 also communicate with respective sensor communication interfaces 98 , 100 , 102 , 104 , 106 , and 108 in accordance with present principles to send information sensed, gathered, and/or received or the like from each assembly's respective sensor to the sensor communication interface 30 of the AVDD 12 for presentation thereon. It is to be understood that the communication interfaces referenced herein, including the interfaces 30 , 34 , 98 , 100 , 102 , 104 , 106 , and 108 may support and/or include a universal serial bus (USB) connection, wired TCP/IP, WiFi TCP/IP, and/or built-in RF transceivers (such as ZWAVE, ZigBee, etc.) in non-limiting embodiments. Furthermore, if desired, the respective processors 74 , 76 , 78 , 80 , 82 , and 84 of the assemblies 44 , 48 , 52 , 62 , 66 , and 70 may store the information from the respective sensors on respective storage mediums 86 , 88 , 90 , 92 , 94 , and 86 .
[0027] One or more biometric sensors 109 may also be provided and may send signals representing biometric parameters of a person to the AVDD. A biometric sensor typically may include a processor “P”, computer memory “M”, and communication interface “CI” according to principles above. Non-limiting examples of biometric sensors include heart rate sensors, temperature sensors, blood pressure sensors, blood sugar sensors, and the like.
[0028] Moving now to FIG. 2 , a flow chart of example logic an AVDD, such as the AVDD 12 , executes in accordance with present principles is shown. Beginning with block 110 , in an example embodiment one or more sensors such as the irrigation valve sensor or the pool heater sensor referenced above can be discovered through device discovery principles known in the art, although in other embodiments a user can enter sensor communication information into the AVDD to establish communications manually. E.g., the sensors may be discovered based on wireless signals emitted by a sensor within a particular radius of a given location, such as a personal residence. Moving from block 110 to block 112 , the logic prompts a user of the AVDD to decide to connect to the one or more sensors that were discovered at block 110 . If the user provides input, e.g. via a remote commander such as the RC 26 described above, in response to the prompt commanding the AVDD to connect to the discovered sensors, the logic continues to block 114 .
[0029] At block 114 , the logic “pushes” and/or provides an application programming interface (API) from the AVDD to the sensor(s). However, it is to be understood that in some embodiments, the API may be provided by a manufacturer of the AVDD to an entity affiliated with the sensor(s) in accordance with present principles, rather than having the AVDD push the API to the sensors. In such an embodiment, the sensor(s) and/or their processors are already capable of providing information in the desired API when the sensor is discovered back at block 110 . Thus, in non-limiting embodiments an entity affiliated with the sensor(s) may be, e.g., a sensor manufacturer vending sensor(s) already being able to provide information in the appropriate API. In other instances, e.g., an entity affiliated with the sensor may be a third party such as a sensor technician that provides and/or pushes the API to the sensor when installing the sensor at a particular location (and thus prior to being discovered by the AVDD in accordance with present principles).
[0030] Continuing in reference to FIG. 2 , at block 116 the logic receives information back from the sensor(s). Concluding FIG. 2 at block 118 , the information from the sensor(s) is displayed on the AVDD in accordance with the API.
[0031] Thus, it is to be understood that one or more sensors such as but not limited to the sensors described herein include respective processors accessing the API and sending the information to an AVDD such as the AVDD 12 in accordance with the API. To reiterate, sensors in accordance with present principles may include, but are not limited to, environmental sensors, ambient light sensors (such as photodiodes in monitored rooms or areas), door position sensors, window covering position sensors, pool heater energization sensors, motion sensors (such as the motion sensor(s) described in U.S. Pat. No. 7,755,052, incorporated herein by reference), valve position sensors, biometric sensors, and/or other sensors including simple switch sensors.
[0032] Now referring to FIG. 3 , a schematic diagram showing a data structure of an exemplary API that may be pushed and/or provided by the AVDD to various sensors automatically when the viewer selects to connect to discovered sensors, or that may be published by a manufacturer of the AVDD to sensor manufacturers so that the sensor manufacturers may pre-program their sensors with the API, is shown. It is to be understood that the API defines, relative to the information from the sensor, content in the information from the sensor to be presented on a display of an AVDD, such as the display 24 referenced above. In some embodiments the API also defines when and where the content is to be presented on the display.
[0033] Thus, as may be appreciated from FIG. 3 , a data structure 120 includes various parameters, such as whether an icon from a sensor should be presented, whether an icon from an AVDD such as the AVDD 12 should be presented, and/or whether alpha-numeric information from the sensor should be presented. Accordingly, content parameters 122 can include types of content to be presented, such as one or more icons and/or alpha-numeric information. Furthermore, in some embodiments the content may include, e.g., only one icon or only alpha-numeric information. As may also be appreciated from FIG. 3 , the data structure 120 may also include parameters 124 regarding where and/or how content should be presented. For example, content may be presented in a full-screen mode such that only the content is displayed, or in, e.g., a bottom portion of the display or a top portion of the display such that the content may be simultaneously displayed with unrelated content such as a television program or motion picture.
[0034] In addition to the above, the data structure 120 may also include parameters 126 regarding when the content from the sensors should be presented. For example, content may be presented only upon receipt of the content or information, and/or receipt of a message containing the content and/or information. Accordingly, in non-limiting embodiments extensible markup language (XML) messaging may be used such that, e.g., the XML is used to encapsulate the content, information, and/or message. Alternatively or in addition to the above, content may be presented at predetermined intervals, such as, e.g., every 5 minutes or every hour. Thus, FIG. 3 shows that the data structure 120 includes a parameter for both presenting content upon receipt and at least one reminder, such as five minutes after the content is received. If desired, reminders can also be repeatedly presented at predetermined intervals. Furthermore, in some embodiments audio alerts and/or audible content pertaining to information and/or content received from the sensor(s) may be presented on the AVDD through, e.g., the speakers 20 , in lieu of or in addition to presentation of visual content.
[0035] Now in reference to FIGS. 4-10 , illustrative exemplary screen shots from an AVDD presenting information and/or content from various sensors such as those referenced above are shown. Thus, FIG. 4 shows that live video may be displayed along with a visual indication on the bottom portion of a display, such as the display 24 referenced above, that an irrigation system such as lawn sprinklers is on, being based on information received from a valve position sensor. FIG. 5 shows that live video may be displayed along with a visual indication on the bottom portion of the display that window blinds are opening, being based on information received from a window coverings position sensor. FIG. 6 shows that live video may be displayed along with a visual indication on the bottom portion of the display that a pool heater is on, being based on information received from a pool heater sensor. FIG. 7 shows that live video may be displayed along with a visual indication on the bottom portion of the display of non-limiting environmental statistics such as temperature and humidity levels, being based on information received from an environment sensor. FIG. 8 shows that a visual indication may be presented on the display indicating, e.g., an “intruder alert” based on the motion of a person sensed by a motion sensor.
[0036] Continuing in reference to the exemplary screen shots disclosed herein, FIG. 9 shows that live video may be displayed along with a visual indication on the bottom portion of the display that the garage door of the residence where the AVDD is disposed is opening, being based on information received from a door position sensor. Concluding with FIG. 10 , live video may be displayed along with a visual indication including an icon on the bottom portion of the display that a light has been turned on in another room of a personal residence in which the AVDD is disposed, being based on information received from a light sensor.
[0037] Additionally, note that a user of an AVDD such as the AVDD 12 may choose whether or not to display information and/or content from the sensors in accordance with present principles. Thus, for example, a user interface may be presented on the AVDD allowing a user to enable presentation of the information and/or content from one or more sensors, or to disable presentation of the information and/or content. Furthermore, it is to be understood that one AVDD presenting information and/or content may, e.g. using Internet capabilities, forward the information and/or content to other AVDDs for presentation thereon. Thus, for example, an AVDD such as a TV may present a user interface to a user allowing the user to forward information and/or content from one or more sensors from the TV to the user's laptop computer or smart phone so that the information and/or content may still be monitored by a user when not viewing the TV.
[0038] FIG. 11 shows an alternate system in which an AVDD 12 a may communicate with one or more sensors 32 a along a direct communication path, which portion of the system can be identical in operation and configuration to the system shown in FIG. 1 . In addition, a home automation platform (HAP) 150 such as, for example, a computer with processor, computer readable medium, display, input device, etc. may receive information from the sensor 32 a along an aggregate path and provide aggregated sensor information to the AVDD 12 a as shown. Thus, when the sensor 32 a is a power sensor such as a current sensor, information from it can be aggregated over a period of time, e.g., 24 hours, by the HAP 150 and then the aggregated sensor information, in this example, total power usage for the past 24 hours, can be presented on the AVDD 12 a along with current power use provided from the sensor 32 along the direct path as shown.
[0039] Furthermore, the HAP 150 (or a sensor or the AVDD or a cloud server) can aggregate data from multiple sensors and provide that aggregated data to the AVDD 12 a. For example, the HAP 150 may provide to the AVDD 12 a for display data indicating that a thermostat has reached a threshold and is activating a climate control unit such as a heater or air conditioner in response, as indicated by a climate control sensor, that the fan associated with the unit is at a particular speed as indicated by a fan speed sensor, and that the current room temperature as sensed by a temperature sensor is at a particular value. In essence, the HAP 150 correlates input from different but related sensors and provides that input to the AVDD for convenient simultaneous presentation of the various inputs from the different but related sensors. Furthermore, the provision of the HAP 150 facilitates the AVDD working with legacy sensors that may not have the capability to execute the API discussed above but that can communicate with the HAP 150 using legacy protocols different from the above-discussed API, with the HAP 150 then communicating with the AVDD using the above-discussed API.
[0040] In some examples, one or more of the devices above (e.g., the HAP or AVDD) monitor plural sensors as described and output an event only if two or more sensor outputs meet “event” criteria. For example, a sound sensor and a motion sensor may both output signals representing the presence of moving humans and animals, and an event “intruder alert” may be generated only responsive to both sensor signals indicating an intruder, i.e., only in response to the sound sensor outputting a signal indicating noise or human speech above (or below) a threshold and the motion sensor indicating a moving object. Responsive to only one sensor outputting a signal indicating an intruder, the “intruder alert” may not be presented, e.g., on the AVDD, in audible and/or visible form. The intruder alert may be sent to the cloud (Internet) for provisioning of the alert to, e.g., a wireless device registered in the cloud to the owner of the premises in which the sensors are disposed, and/or to law enforcement agencies.
[0041] As a further example, a “medical alert” may be generated by, e.g., the HAP or AVDD responsive to two or more biometric sensors outputting signals satisfying a medical alert threshold, but not responsive to only a single biometric sensor outputting such a signal. For example, a “medical alert” may be output (locally and/or to the cloud) responsive to two or more biometric sensors outputting signals satisfying “alert” thresholds. Thus, a medical alert may be generated only responsive to both a heart rate sensor indicating a pulse in excess of a threshold and a temperature in excess of a threshold, but not responsive to only a single biometric sensor outputting a signal indicating a medical emergency.
[0042] FIG. 12 illustrates that device discovery may be initiated on the sensor side, commencing at block 152 . When a sensor discovers the AVDD it may request to be added to the AVDD's sensor group at block 154 , and if the AVDD accepts the sensor at decision diamond 156 , the AVDD assumes control of communication with the sensor at block 158 . This may include presenting an onscreen instruction to the user to take particular action with respect to the sensor, e.g., operating a button or key on the sensor in a particular fashion to authenticate the sensor to the AVDD. The AVDD can then accept further communication from the sensor.
[0043] On the other hand, if the AVDD does not accept sensor communication at decision diamond 156 the logic flows to block 160 in which the sensor waits in standby for future instructions, if any, from the AVDD.
[0044] While the particular HOME AUDIO VIDEO DISPLAY DEVICE (AVDD) AS SENSOR MONITOR is herein shown and described in detail, it is to be understood that the subject matter which is encompassed by the present invention is limited only by the claims. | Method, computer storage device, and system that establish communication with at least first and second sensors, receive information from the sensors, and determine whether the information from the first sensor satisfies a first alert threshold. It is also determined whether the information from the second sensor satisfies a second alert threshold. Responsive to a determination that the information from the first sensor satisfies the first alert threshold and that the information from the second sensor does not satisfy the second alert threshold, an alert signal is not generated. On the other hand, responsive to a determination that the information from the first sensor satisfies the first alert threshold and that the information from the second sensor satisfies the second alert threshold, the alert signal is generated for output thereof to a display device. | 6 |
CROSS REFERENCE TO RELATED PATENT APPLICATION
The present patent application claims the right of priority under 35 U.S.C. §120 and is a Continuation-In-Part of U.S. patent application Ser. No. 09/098,817, filed Jun. 17, 1998 now abandoned.
FIELD OF THE INVENTION
The invention is directed to a thermoplastic molding composition, which contains ABS and polycarbonate and to articles molded therefrom, and more particularly to metal plated articles molded therefrom.
SUMMARY OF INVENTION
A thermoplastic molding composition containing a major amount of polycarbonate and a lesser amount of butadiene based graft polymer is disclosed. The inventive composition is especially suited for the preparation of a molded article wherein at least some of its surface is metallized by an electroless plating process. The thus plated article is characterized in its improved heat resistance and excellent adhesion of its metal plating.
BACKGROUND OF INVENTION
Thermoplastic molding composition containing polycarbonates and ABS polymers have been known for some time, see for example DE-A 1 170 141 which describes the favorable processing properties of such molding compositions. Also relevant are U.S. Pat. Nos. 3,130,177, 3,162,695 and 3,852,393 and British Patent No. 1,253,226.
Also known are thermoplastic molding compositions containing polycarbonate and acrylate based plating modifiers (U.S. Pat. No. 4,828,921) or ABS which are suitable for electroless metal plating. In general, the polycarbonate content in these compositions is kept low as it has long been recognized that the presence of polycarbonate in relatively high amounts is the cause of difficulties in electroless metal-plating (see U.S. Pat. Nos. 5,198,096 and 5,087,524). On the other hand, the heat resistance of the composition is directly related to the polycarbonate level. Blends containing a higher content of polycarbonate feature better thermal performance. The art has long sought a molding composition that would combine good heat resistance with good plating characteristics. The composition of the present invention addresses this goal. Special processes for electroless plating of polycarbonate have been described in U.S. Pat. Nos. 5,087,524 and 5,198,096.
Processes for electroless plating have been disclosed in U.S. Pat. No. 4,125,649 and in the Encyclopedia of Polymer Science and Technology, Vol. 8, both incorporated by reference herein.
DETAILED DESCRIPTION OF THE INVENTION
The thermoplastic molding composition of the invention comprises:
A) 51 to 90 parts by weight of an aromatic polycarbonate;
B) a positive amount up to 30 parts by weight of a rubber free vinyl copolymer of 50 to 99 percent B.1 and 1 to 50 percent B.2, the percents being relative to the weight of the copolymer, where B.1is at least one member selected from the group consisting of styrene, α-methyl styrene, nucleus-substituted styrene, and methyl methacrylate and where B.2 is at least one member selected from the group consisting of acrylonitrile, methyl methacrylate, maleic anhydride, N-alkyl-substituted maleic imide and N-aryl-substituted maleic imide;
C) 5 to 30 parts by weight of a first graft polymer containing 10 to 90 percent of a first graft phase C.1 and 10 to 90 percent of a first graft base C.2, said percents relative to the weight of said first graft polymer, where said first graft phase C.1 comprise
C.1.1 50 to 99 percent relative to the weight of said first graft phase of at least one member selected from the group consisting of styrene, α-methyl styrene, nucleus-substituted styrene, C 1-8 alkyl methacrylate and C 1-8 alkyl acrylate, and
C.1.2 1 to 50 percent relative to the weight of said first graft phase of at least one member selected from the group consisting of acrylonitrile, methacrylonitrile, C 1-8 alkyl methacrylate, C 1-8 alkyl acrylate, maleic anhydride, C 1-4 alkyl substituted maleic imide and phenyl-N-substituted maleic imide,
and where said first graft base comprise a crosslinked, particulate elastomer selected from the group consisting of butadiene and copolymers of butadiene with other ethylenically unsaturated monomers having an average particle diameter (d50 value) of 0.05 to 0.5 microns;
D) 1 to 15 parts by weight of a second graft polymer containing 78 to 95 percent of a second graft phase D.1 and 5 to 22 percent of a second graft base D.2, said percents relative to the weight of said second graft polymer, where said second graft phase D.1 comprise
D.1.1 65 to 85 percent relative to the weight of said second graft phase of at least one member selected from the group consisting of styrene, α-methyl styrene, nucleus-substituted styrene, C 1-8 alkyl methacrylate and C 1-8 alkyl acrylate, and
D.1.2 15 to 35 percent relative to the weight of said second graft phase of at least one member selected from the group consisting of acrylonitrile, methacrylonitrile, C 1-8 alkyl methacrylate, C 1-8 alkyl acrylate, maleic anhydride, C 1-4 alkyl substituted maleic imide and phenyl-N-substituted maleic imide,
and where said second graft base comprise a non-crosslinked elastomer selected from the group consisting of polybutadiene and copolymers of butadiene with at least one member selected from the group consisting of styrene, isoprene and C 4-8 alkyl acrylate having a weight average molecular weight of 50,000 to 250,000 g/mole and where the second graft polymer has a weight average particle diameter of 0.6 to 20 microns; where the sum of A)+B)+C)+D) totals 100 resin, and
E) 0.1 to 4 parts per 100 parts resin of a wax containing at least one ester group having a weight average molecular weight of 300 to 5000 g/Mol and a melting point below 400° C.
In a preferred embodiment, the components of the inventive composition are present in the following amounts:
Component A—55 to 85 parts by weight,
Component B—2 to 20 parts by weight,
Component C—10 to 30 parts by weight,
Component D—2 to 10 parts by weight, and
0.2 to 3 parts of Component E.
In a most preferred embodiment, the components of the inventive composition are present in the following amounts:
Component A—65 to 80 parts by weight,
Component B—2 to 5 parts by weight,
Component C—10 to 25 parts by weight,
Component D—2 to 10 parts by weight, and
0.2 to 3 parts of Component E.
Preferably, the first graft polymer comprise 30 to 80 percent of C.1 and 70 to 20 percent of C.2.
In a yet additionally preferred embodiment, component D contains 94 to 80 percent of a second graft phase D.1, and 6 to 20 percent by weight of a second graft base D.2.
Component A
Suitable polycarbonate resins for preparing the copolymer of the present invention are homopolycarbonates and copolycarbonates and mixtures thereof.
The polycarbonates generally have a weight average molecular weight of 10,000 to 200,000, preferably 20,000 to 80,000, and their melt flow rate, per ASTM D-1238 at 300° C., is about 1 to about 65 g/10 min., preferably about 2 to 15 g/10 min. They may be prepared, for example, by the known diphasic interface process from a carbonic acid derivative such as phosgene and dihydroxy compounds by polycondensation (see German Offenlegungsschriften 2,063,050; 2,063,052; 1,570,703; 2,211,956; 2,211,957 and 2,248,817; French Patent 1,561,518; and the monograph by H. Schnell, “Chemistry and Physics of Polycarbonates”, Interscience Publishers, New York, N.Y., 1964, all incorporated herein by reference).
In the present context, dihydroxy compounds suitable for the preparation of the polycarbonates of the invention conform to the structural formulae (1) or (2).
wherein
A denotes an alkylene group with 1 to 8 carbon atoms, an alkylidene group with 2 to 8 carbon atoms, a cycloalkylene group with 5 to 15 carbon atoms, a cycloalkylidene group with 5 to 15 carbon atoms, a carbonyl group, an oxygen atom, a sulfur atom, —SO— or —SO 2 or a radical conforming to
e and g both denote the number 0 to 1;
Z denotes F, Cl, Br or C 1 -C 4 alkyl and if several Z radicals are substituents in one aryl radical, they may be identical or different from one another;
d denotes an integer of from 0 to 4; and
f denotes an integer of from 0 to 3.
Among the dihydroxy compounds useful in the practice of the invention are hydroquinone, resorcinol, bis-(hydroxyphenyl)-alkanes, bis-(hydroxyphenyl)-ethers, bis-(hydroxyphenyl)-ketones, bis-(hydroxyphenyl)-sulfoxides, bis-(hydroxyphenyl)-sulfides, bis-(hydroxyphenyl)-sulfones, α,α-bis-(hydroxyphenyl)-diisopropyl-benzenes, as well as their nuclear-alkylated compounds and dihydroxydiphenyl cycloalkanes. These and further suitable aromatic dihydroxy compounds are described, for example, in U.S. Pat. Nos. 5,227,458; 5,105,004; 5,126,428; 5,109,076; 5,104,723; 5,086,157; 3,028,356; 2,999,835; 3,148,172; 2,991,273; 3,271,367; and 2,999,846, all incorporated herein by reference.
Further examples of suitable bisphenols are 2,2-bis-(4-hydroxy-phenyl)-propane (bisphenol A), 2,4-bis-(4-hydroxyphenyl)-2-methyl-butane, 1,1-bis-(4-hydroxyphenyl)-cyclohexane, α,α′-bis-(4-hydroxy-phenyl)-p-diisopropylbenzene, 2,2-bis-(3-methyl-4-hydroxyphenyl)-propane, 2,2-bis-(3-chloro-4-hydroxyphenyl)-propane, bis-(3,5-dimethyl-4-hydroxyphenyl)-methane, 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)-propane, bis-(3,5-dimethyl-4-hydroxyphenyl)-sulfide, bis-(3,5-dimethyl-4-hydroxy-henyl)-sulfoxide, bis-(3,5-dimethyl-4-hydroxyphenyl)-sulfone, dihydroxyenzophenone, 2,4-bis-(3,5-dimethyl-4-hydroxyphenyl)-cyclohexane, α,α′-bis-(3,5-dimethyl-4-hydroxyphenyl)-p-diisopropylbenzene and 4,4′-sulfonyl diphenol.
Examples of particularly preferred aromatic bisphenols are 2,2-bis-(4-hydroxyphenyl)-propane, 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)-propane, 1,1-bis-(4-hydroxyphenyl)-cyclohexane and 1,1-bis-(4-hydroxy-phenyl)-3,3,5-trimethylcyclohexane.
The most preferred bisphenol is 2,2-bis-(4-hydroxyphenyl)-propane (bisphenol A).
The polycarbonates of the invention may entail in their structure units derived from one or more of the suitable bisphenols.
Among the resins suitable in the practice of the invention are phenolphthalein-based polycarbonates, copolycarbonates and terpolycarbonates such as are described in U.S. Pat. Nos. 3,036,036 and 4,210,741, both incorporated by reference herein.
The polycarbonates of the invention may also be branched by condensing therein small quantities, e.g., 0.05 to 2.0 mole % (relative to the bisphenols) of polyhydroxy compounds.
Polycarbonates of this type have been described, for example, in German Offenlegungsschriften 1,570,533; 2,116,974 and 2,113,374; British Patents 885,442 and 1,079,821 and U.S. Pat. No. 3,544,514. The following are some examples of polyhydroxyl compounds which may be used for this purpose: phloroglucinol; 4,6-dimethyl-2,4,6-tri-(4-hydroxy-phenyl)-heptane; 1,3,5-tri-(4-hydroxyphenyl)-benzene; 1,1,1-tri-(4-hydroxy-phenyl)-ethane; tri-(4-hydroxyphenyl)-phenylmethane; 2,2-bis-[4,4-(4,4′-dihydroxydiphenyl)]-cyclohexyl-propane; 2,4-bis-(4-hydroxy-1-isopropy-lidine)-phenol; 2,6-bis-(2′-dihydroxy-5′-methylbenzyl)-4-methyl-phenol; 2,4-dihydroxybenzoic acid; 2-(4-hydroxyphenyl)-2-(2,4-dihydroxy-phenyl)-propane and 1,4-bis-(4,4′-dihydroxytriphenylmethyl)-benzene. Some of the other polyfunctional compounds are 2,4-dihydroxy-benzoic acid, rimesic acid, cyanuric chloride and 3,3-bis-(4-hydroxyphenyl)-2-oxo-2, 3-dihydroindole.
In addition to the polycondensation process mentioned above, other rocesses for the preparation of the polycarbonates of the invention are olycondensation in a homogeneous phase and transesterification. The suitable processes are disclosed in the incorporated herein by reference U.S. Pat. Nos. 3,028,365; 2,999,846; 3,153,008 and 2,991,273.
The preferred process for the preparation of polycarbonates is the interfacial polycondensation process.
Other methods of synthesis in forming the polycarbonates of the invention such as disclosed in U.S. Pat. No. 3,912,688, incorporated herein by reference, may be used.
Suitable polycarbonate resins are available in commerce, for instance, Makrolon FCR, Makrolon 2600, Makrolon 2800 and Makrolon 3100, all of which are bisphenol based homopolycarbonate resins differing in terms of their respective molecular weights and characterized in that their melt flow indices (MFR) per ASTM D-1238 are about 16.5 to 24, 13 to 16, 7.5 to 13.0 and 3.5 to 6.5 g/10 min., respectively. These are products of Bayer Corporation of Pittsburgh, Pennsylvania.
A polycarbonate resin suitable in the practice of the invention is known and its structure and methods of preparation have been disclosed, for example, in U.S. Pat. Nos. 3,030,331; 3,169,121; 3,395,119; 3,729,447; 4,255,556; 4,260,731; 4,369,303; 4,714,746 and 5,227,458, all of which are incorporated by reference herein.
Component B
The rubber-free, thermoplastic vinyl copolymer component B of the present invention, contains
B.1) 50 to 99 percent relative to the weight of the copolymer of at least one member selected from the group consisting of styrene, alpha-methyl styrene, nucleus-substituted styrene and methylmeth-acrylate and
B.2) 1 to 50 percent relative to the weight of the copolymer of at least one member selected from the group consisting of acrylonitrile, methyl methacrylate, maleic anhydride, N-alkyl-substituted maleic imide and N-aryl-substituted maleic imide.
The weight average molecular weight (as determined by light scattering or sedimentation) of the copolymer of component B is in the range of 15,000 to 200,000.
Particularly preferred ratios by weight of the components making up the copolymer B are 60 to 95 percent of B.1 and 40 to 5 percent of B.2. Particularly preferred copolymers B include those of styrene with acrylonitrile, optionally with methyl methacrylate; copolymers of alpha.-methyl styrene with acrylonitrile, optionally with methyl methacrylate and copolymers of styrene and alpha.-methyl styrene with acrylonitrile, optionally with methyl methacrylate.
The copolymers of component B are known and the methods for their preparation, for instance, by radical polymerization, more particularly by emulsion, suspension, solution and bulk polymerization are also well documented in the literature. The source of B in the claimed composition may be the ungrafted portion of components C and/or D and/or specifically added copolymer.
Component C
The first graft polymer contains 10 to 90 percent of a first graft phase C.1 and 10 to 90 percent of a first graft base C.2, said percents relative to the weight of said first graft polymer. The first graft phase C.1 comprises
C.1.1 50 to 99 percent relative to the weight of said first graft phase of at least one member selected form the group consisting of styrene, α-methyl styrene, nucleus-substituted styrene, C 1-8 alkyl methacrylate and C 1-8 alkyl acrylate, and
C.1.2 1 to 50 percent relative to the weight of said first graft phase of at least one member selected from the group consisting of acrylonitrile, methacrylonitrile, C 1-8 alkyl methacrylate, C 1-8 alkyl acrylate, maleic anhydride, C 1-4 alkyl substituted maleic imide and phenyl-N-substituted maleic imide.
The first graft base comprise a crosslinked, particulate elastomer elected from the group consisting of butadiene and copolymers of butadiene with other ethylenically unsaturated monomers having an average particle diameter (d50 value) of 0.05 to 0.5 microns.
The first graft polymer of the inventive composition is well known in the art and is commercially available. A general description of such graft polymers is included in “Methoden der Organischen Chemie” (Houben Weyl), Vol. 14/1, Georg Thieme Verlag, Stuttgart 1961, pages 393-406 and in C. B. Bucknall, “Toughened Plastics”, Appl. Science Publishers, London, 1977, incorporated herein by reference. Suitable graft polymers have been disclosed in U.S. Pat. Nos. 3,564,077; 3,644,574 and 3,919,353, which are incorporated herein by reference.
Particularly preferred first graft polymers C may be obtainable by grafting of at least one (meth)acrylate and/or acrylonitrile and/or styrene as the first grafted phase onto a first graft base containing butadiene polymer having a gel content of at least 50% by weight (as measured in toluene), the degree of grafting (the degree of grafting is the weight ratio of graft monomers grafted on to the graft base and the monomers which were not grafted and is dimensionless) being between 0.15 and 10. In addition to butadiene units, the graft base may contain up to 50% by weight, based on the weight of the butadiene units, of other ethylenically unsaturated monomers, such as styrene, acrylonitrile, esters of acrylic or methacrylic acid containing 1 to 4 carbon atoms in the alcohol component (such as methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate), vinyl esters and/or vinyl ethers. The preferred graft base contains only polybutadiene.
Since the graft monomers do not have to be completely grafted onto the graft base in the grafting reaction, the first graft polymer C in the context of the invention is also understood to include products which are obtained by polymerization of the graft monomers in the presence of the graft base.
The average particle sizes (d 50) is the diameter above which 50% by weight of the particles and below which 50% by weight of the particles lie. It may be determined by ultracentrifuge measurement (W. Scholtan, H. Lange, Kolloid Z. und Z. Polymere 250 (1972), 782-796).
The gel content of the graft base may be determined in dimethyl formamide. (M. Hoffmann, H. Kromer, R. Kuhn, Polymeranalytik I und II, Georg Thieme-Verlag, Stuttgart, 1977).
The first graft polymer may be produced by known methods, such as bulk, suspension, emulsion or bulk suspension polymerization, preferably by emulsion polymerization.
The average particle size (d 50) of the first graft polymer component C of the present invention is about 0.05 to 0.5 microns, preferably 0.1 to 0.4 microns.
Component D
Component D, a second graft polymer is present in an amount of 1 to 15 parts by weight.
It contains 78 to 95 percent of a graft phase D.1 and 5 to 22 percent of a graft base D.2, the percents being relative to the weight of the second graft polymer. The graft phase D.1 comprise
D.1.1 65 to 85 percent relative to the weight of the graft phase of at least one member selected from the group consisting of styrene, alpha.-methyl styrene, nucleus-substituted styrene, C 1-8 alkyl methacrylate and C 1-8 alkyl acrylate, and
D.1.2 15 to 35 percent relative to the weight of the graft phase of at least one member selected from the group consisting of acrylonitrile, methacrylonitrile, C 1-8 alkyl methacrylate, C 1-8 alkyl acrylate, maleic anhydride, C 1-4 alkyl substituted maleic imide and phenyl-N-substituted maleic imide.
and where said second graft base comprise a crosslinked elastomer selected from the group consisting of polybutadiene and copolymers of butadiene with at least one member selected from the group consisting of styrene, isoprene and C 4-8 alkyl acrylate having a weight average molecular weight of 50,000 to 250,000 g/mole and where the second graft polymer has a weight average particle diameter of 0.6 to 20 microns;
In a preferred embodiment, the graft phase contains 80 to 94 percent of D.1.1 and 6 to 20 percent of D.1.2. In a further preferred embodiment, the graft base D.2 is present at an amount of 8 to 18 percent relative to the weight of the second graft polymer.
The second graft polymer of the invention, Component D, is largely similar to component C with a few important differences as these are noted above. This second graft polymer is also well known in the art and is commercially available. This graft has been extensively described in the literature, for instance in, “Methoden der Organischen Chemie” (HoubenWeyl), Vol. 14/1, Georg Thieme Verlag, Stuttgart, 1961, which is incorporated herein by reference.
Particularly preferred second graft polymer D may be obtainable by grafting of at least one (meth)acrylate and/or acrylonitrile and/or styrene as the grafted phase onto a graft base containing butadiene polymer. In addition to butadiene units, the graft base of Component D may contain up to 50% by weight, based on the weight of the butadiene units, of other ethylenically unsaturated monomers, such as styrene, isoprene or C 4-8 alkyl acrylate. The preferred graft base contains only polybutadiene or poly (butadiene-styrene) copolymer.
Since the graft monomers do not have to be completely grafted onto the graft base in the grafting reaction, the graft polymer D is also understood to include products which are obtained by polymerization of the graft monomers in the presence of the graft base.
The weight average particle size of the second graft polymer, component D, of the present invention is about 0.6 to 20.0 microns, preferably 0.6 to 5 microns, most preferably 0.6 to 1.6 microns.
The second graft polymer may be produced by known methods, such as suspension, bulk or mass graft polymerization. A preferred method entails mass or suspension graft polymerization of the comonomers of the grafted phase, for instance, styrene and acrylonitrile, in the presence of polybutadiene.
In a preferred embodiment, Component D contains 10 to 16% by weight of graft base, which contains only polybutadiene. The weight average molecular weight (GPC) of the free SAN in the styrene/-acrylonitrile graft polymer is in the range from 50,000 to 150,000 and the grafted polybutadiene has a weight average particle size in the range of from 0.6 to 1.6 microns.
Component E
Component E of the inventive composition is a wax which melts below 400° C. Waxes suitable in the practice are well known and are available in commerce. Chemically, these are compounds which are esters of a high molecular weight fatty acid with a high molecular weight alcohol, including mixtures of such esters. The molecular weight, weight average, or, where applicable, formula of the suitable waxes is in the range of 300 to 5000 g/mole. The alcohol component of the ester group is selected from among aliphatic, linear or branched, mono, bi-, or polyfunctional alcohols with more than two carbon atoms, preferably 3 to 22 carbon atoms, the acid component being mono-, di-, or polyfunctional aliphatic acids with more than 3 carbon atoms, preferred more than 5 carbon atoms. These compounds are known and are widely used as additives to polymeric molding compositions for their release function. Preferred compounds are the reaction products of C 4 to C 8 alcohols and C 6 to C 18 acids. Examples of preferred type esters are butylstearate, butyladipate and dioctyladipate.
Component E is present in the inventive composition in an amount of 0.1 to 4 parts per 100 resin of the total of A, B, C and D.
In addition, the composition of the invention may advantageously contain other additives such as plasticizers, antioxidants, plating additives, silicone oil, stabilizers, flame-retardants, fibers, mineral fibers, mineral fillers, dyes, pigments and the like.
The preparation of the inventive composition follows conventional rocedures which are well known in the art. Usually, however, they are extrusion blended or compounded in a high intensity blender such as a Banbury Mixer or twin-screw extruder.
The invention is now described with reference to the following examples which are for the purposes of illustration only and are not intended to imply any limitation on the scope of the invention.
EXAMPLES
Components Used:
Polycarbonate—A linear polycarbonate based on bisphenol A having a melt viscosity of 4.5 grams per 10 minutes at 300° C. with 1.2 kg load; ASTM D 1238.
ABS-1 and ABS-2—prepared by the graft emulsion polymerization of styrene and acrylonitrile in a weight ratio of S/AN of about 70:30 in the presence of polybutadiene. ABS-1 and ABS-2 contained, respectively, 60 and 38 percent by weight of polybutadiene. The weight average molecular weights of the ungrafted SAN polymer fraction (GPC per ASTM Method D 3536-76) were respectively 80,000 and 100,000 g/mole. The ABS polymer is recovered from the emulsion by conventional coagulation, filtration and washing. The grafted polybutadiene has an average particle size of 0.3 to 0.2 micrometer measured as a d50 value measured by Photon Correlation Spectroscopy using a Brookhaven Instrument Company BI-90 Particle Size.
ABS-3—prepared by the graft suspension polymerization of styrene and acrylonitrile in a weight ratio of 72:28 in the presence of polybutadiene.
ABS-3 contains 14% by weight of polybutadiene. The weight average molecular weight determined by GPC of the free SAN in the styrene/acrylonitrile graft polymer was 110,000 g/mole and the grafted polybutadiene had an average particle size of 0.8 microns
SAN-1—a copolymer of styrene and acrylonitrile made by continuous bulk polymerization. The copolymer contains 75.5 weight % styrene and 24.5 weight % acrylonitrile.
Each of the exemplified compositions contained 0.2 parts of butyl stearate per 100 resin of the total of A, B, C and D.
An extrusion process physically blended the components of the polymer blends of each example. This was carried out in a 34 mm Leistritz twin-screw extruder (24:1 L:D screw; 250 revolutions per minute; at 260° C.). A commercial antioxidant having no criticality in the present context was included in the compositional makeup at a level of 0.1% by weight. The die temperature was 260° C. The extruded material is passed through a water bath and pelletized.
The pelletized material is then injection molded into specimens for testing.
Electroless plating was carried out by the process described below:
Specimens tested for peel strength were prepared in the following manner:
Chromic Acid/Sulfuric Acid Etching
10
minutes at 68° C.
Dead Rinse
1
minute
Cold Water Rinse
2
minutes
Neutralizer-Shipley PM 954
4
minutes at 40° C.
Cold Water Rinse
1
minute
Activator-MacDermid D-34 C
4
minutes at 40° C.
Cold Water Rinse
1
minute
Accelerator-Shipley PM 964
2
minutes at 52° C.
Cold Water Rinse
1
minute
Electroless Copper-Shipley 251
10
minutes at 40° C.
Cold Water Rinse
Copper Strike
3
minutes @ 1 volt at 28° C.
3
minutes @ 2 volts
2
minutes @ 3 volts
Acid Copper
120
minutes @ 40
amps/square foot at 28° C.
The plate adhesion was measured in accordance with ASTM method B533-85 and Vicat temperature was measured in accordance with the procedure described in ASTM standard 1525.
The examples shown below illustrate the plate adhesion and heat performance.
In Example 1 (control) (not according to the invention) the heat resistance, determined as Vicat Temperature, is very high, yet the plate adhesion is very poor. In Example 5 (control) (not according to the invention) the adhesion is very good, yet the heat resistance is unacceptably low. Examples 2 and 4 demonstrate the invention where both heat resistance and adhesion are improved.
1
2
3
4
5
Poly-
70
70
70
70
50
carbonate
ABS-1
14
ABS-2
20
20
16
25
ABS-3
5
10
10
10
SAN-1
16
5
4
15
Plate Adhesion
0.26
6.2
4.5
6.0
5.8
(lbs/in)
Vicat Temperature
140
141
140
141
129
(° C.)
Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the nvention except as it may be limited by the claims. | A thermoplastic molding composition comprising, (A) an aromatic polycarbonate; (B) a single rubber-free copolymer, e.g., of styrene and acrylonitrile; (C) a first graft polymer; (D) a second graft polymer; and (E) a wax, is described. The single rubber-free copolymer (B), and first and second graft polymers (C) and (D) are prepared from a specific selection of graft phases and graft bases. The graft base of the first graft polymer (C) comprises a crosslinked, particulate elastomer having an average particle diameter of 0.05 to 0.5 microns. The second graft polymer (D) has an average particle diameter of 0.6 to 20 microns. The thermoplastic compositions of the present invention are well suited for the preparation of molded articles that may be metalized over at least a portion of their surface by means of an electroless plating process. Such electroless plated articles are characterized as having improved heat resistance and adhesion of the metal plating. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional application of Ser. No. 09/878,947 filed on June 13, 2001, and now Patent No. ______.
BACKGROUND OF THE INVENTION
[0002] The invention is directed to a door or lid which is normally hinged to a washer opening to define a top-loading or a front-loading washer. Conventionally such doors or lids have been made of metal with or without a glass panel through which the interior of the washer can be viewed.
DESCRIPTION OF THE RELATED ART
[0003] U.S. Pat. No. 4,695,420 granted on Sep. 22, 1987 and assigned to Caterpillar, Inc. makes reference to the desirability of injection molding plastic articles having a variety of complex shapes and sizes including panels and doors of vehicles or equipment enclosures, such as cab doors. Such cab doors were originally manufactured by utilizing a flat rigid frame fabricated from metal to which is unitized a window in what is termed a costly and time-consuming operation. The window or glazing is floated in a soft gasket channel isolated from the frame to reduce shock-loads and thermal stresses induced by varying coefficients of thermal expansion between the metal frame and the glazing/glass panel. It is believed that the process just described is workable because the window panes in all cases are sheets of transparent plastic material, such as polycarbonate and acrylic with the preferred material being a polycarbonate having a silicone hard coat applied thereto to make the polycarbonate glazing or window pane more scratch-resistant. The silicone hard coat on the peripheral edge is removed by sanding or grinding to assure good bonding between the eventually molded frame and the polycarbonate glazing.
[0004] With the advent of excellent molding qualities of modern plastic materials, an effort was made to form a door by first manufacturing a pre-shaped pane of transparent glass and subsequently integrally molding the latter into a door frame as the window thereof. Following this process, the window pane was distorted and wavy and the door frame had a tendency to warp. However, by utilizing a high modulus plastic material, such as polyurethane and a shrink-reducing filler material, undesired high temperature rise from exothermic reaction was moderated, particularly when a catalyst was added in sufficient amounts to control the weight of the reaction and the heat evolution. Also, by heating the glass and forming the frame by reaction injection molding, both the frame and the glass window pane thermally contract similarly absent window pane buckle and with bonding of the edges of the glass window pane to the frame.
[0005] Glass and specifically tempered glass have heretofore never been provided with an injection molded polymeric/copolymeric frame to form a door or lid, and particularly a washer lid. However, injection-molding polymeric/copolymeric material as an encapsulation or border to form a shelf is well known, as is evidenced by U.S. Pat. No. 5,273,354 granted on Dec. 28, 1993; U.S. Pat. No. 5,362,145 granted on Nov. 8, 1994; U.S. Pat. No. 5,403,084 granted on Apr. 4, 1995; U.S. Pat. No. 5,429,433 granted on Jul. 4, 1995; U.S. Pat. No. 5,441,338 granted on Aug. 15, 1995; U.S. Pat. No. 5,454,638 granted on Oct. 3, 1995; U.S. Pat. No. 5,540,493 granted on Jul. 30, 1996 and U.S. Pat. No. 5,735,589 granted on Apr. 7, 1998.
[0006] Other patents dealing with glass to which material is injection molded normally include windshields to which a gasket is molded and/or cured in situ so as to encapsulate a marginal peripheral edge of the windshield. Typical of such window assemblies and methods of forming the same are found in such patents as U.S. Pat. No. 4,778,366 granted on Oct. 18, 1998; U.S. Pat. No. 4,688,752 granted on Aug. 25, 1987 and U.S. Pat. No. 4,732,553 granted on Mar. 22, 1988.
[0007] Other patents which were located during the search of the instant invention include U.S. Pat. No. 4,543,283 granted on Sep. 22, 1987; U.S. Pat. No. 3,843,982 granted on Oct. 29, 1974; U.S. Pat. No. 6,146,574, granted on Nov. 14, 2000 and U.S. Pat. No. 4,336,301 granted on Jun. 22, 1982.
SUMMARY OF THE INVENTION
[0008] The present invention is specifically directed to a door or lid for a washer, but contrary to the door of U.S. Pat. No. 4,695,420, the transparent panel is constructed from tempered glass and an open frame-like encapsulation is preferably a polymeric/copolymeric synthetic plastic material in the form of acrylonitrile/styrene/acrylate polymer blended with mica glass beads at a ratio of substantially 70%-30% to 90%-10% by weight, but preferably 80%-20% by weight. The latter specifics of the blended material which is injection molded to form the open frame-like encapsulation achieves a much lower shrink ratio and elasticity, as compared to polypropylene which is normally used in the injection molding of a tempered glass substrate to form a shelf (not a door). Since tempered glass or a similar glass substrate has virtually a zero coefficient of expansion, the same obviously will not expand or contract in relationship to the expansion or contraction of conventional polymeric/copolymeric material, such as polypropylene. Consequently, typical “weld lines” created in the injection molded open frame-like encapsulation or border tend to fracture, particularly as such parts experience temperatures varying between −30° F. to +104° F. However, through the utilization of the specific blended materials latter defined at the ratios stated, such fracture has been essentially eliminated and the washer door or lid of the present invention achieves unexpected longevity, absent deterioration, and aesthetic characteristics at competitive prices, particularly at higher price-ranged washers.
[0009] The aesthetics of the washer lid are also enhanced by designing the exterior of the frame-like encapsulation which is exposed to the consumer as a relatively smooth, unbroken surface except as might otherwise be desired by a washer manufacturer who might specify a recess in the outer surface for reception of a decal, label or the like carrying trademark or other information. The interior of the washer lid which is less susceptible to scrutiny because of it being opened essentially only when the washer is being loaded or unloaded is engineered to include structural characteristics necessary for optimum functionality of the washer lid including, for example, an internally stepped relatively thick inner periphery of the frame-like encapsulation which securely grips and reinforces the peripheral edge of the tempered glass panel, an outboard depending peripheral skirt achieving exterior peripheral rigidity of the frame-like encapsulation, an indiscrete handle portion along an underside of a front wall of the encapsulation which is essentially unobservable when the washer lid is closed, a reinforced corner for a switch actuator, and opposite rear corners rigidly supporting hinges which are utilized to hinge the washer lid to an associated washer opening for movement between open and closed positions thereof.
[0010] With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 is a fragmentary top perspective view, and illustrates a washer with a washer lid or door of the present invention hinged thereto in its closed position.
[0012] [0012]FIG. 2 is a fragmentary perspective view of the washer of FIG. 1, and illustrates the washer lid in its open position.
[0013] [0013]FIG. 3 is a bottom plan view of the washer lid or door, and illustrates a tempered glass panel bonded by an open frame-like encapsulation formed of one-piece injection molded polymeric/copolymeric plastic material.
[0014] [0014]FIG. 4 is a fragmentary cross sectional view through a corner portion of two identical rear corners of the washer lid, and illustrates a generally L-shaped hinge defined by a mounting portion and a pintle portion with the former being fastened to a depending peripheral skirt of the frame-like encapsulation and the pintle portion passing through a slot of the depending peripheral skirt.
[0015] [0015]FIG. 5 is an exterior fragmentary side elevational view of the hinge of FIG. 4, and illustrates the details thereof.
[0016] [0016]FIG. 6 is an interior fragmentary side elevational view of the hinge of FIG. 4.
[0017] [0017]FIG. 7 is a fragmentary bottom plan view of a forward corner of the frame-like encapsulation, and illustrates a switch actuator seated upon reinforcing ribs projecting from a top panel of the frame-like encapsulation and being secured to the peripheral skirt by fasteners.
[0018] [0018]FIG. 8 is an outside fragmentary side elevational view of the forward corner illustrated in FIG. 7, and illustrates details of the switch actuator.
[0019] [0019]FIG. 9 is a fragmentary cross sectional view of the peripheral skirt of the corner of FIG. 7, and illustrates further details of the switch actuator.
DETAILED DESCRIPTION OF THE INVENTION
[0020] A washer 10 is illustrated in FIGS. 1 and 2 of the drawings and includes a conventional washer body 11 having an interior tub or chamber 12 including an upper frame 13 to which is hinged a novel washer lid or door 20 of the present invention. The upper frame 13 defines an upstanding inner peripheral wall 14 (FIGS. 2 and 4) at opposite rear corners (unnumbered) which the upper frame 13 is provided with openings 15 (FIG. 4) for hinging the washer lid 20 thereto in a manner to be described more fully hereinafter.
[0021] A conventional agitator (not shown) is mounted in the tub or chamber 12 and reciprocates arcuately in a conventional fashion. A conventional safety switch or “ON”/“OFF” switch 18 (FIG. 2) is carried by and beneath an apertured horizontal frame portion 16 of the upper frame 13 of the washer 10 , and is switched “on” and “off” by the washer lid 20 in a manner to be described more filly hereinafter.
[0022] The washer lid or door 20 includes a tempered glass panel 21 of a predetermined peripheral configuration defined by a substantially continuous peripheral edge 22 . The glass panel 21 further includes opposite inner and outer surfaces 23 , 24 , respectively, bridged by the peripheral edge 22 . A peripheral portion 25 of the glass panel 21 is defined by the peripheral edge 22 and immediately adjacent surface portions of the opposite inner and outer surfaces 23 , 24 , respectively.
[0023] An open frame-like encapsulation or border 30 is formed as a one-piece of injection molded polymeric/copolymeric synthetic plastic material. The polymeric/copolymeric synthetic plastic material is preferably acrylonitrile-styrene-acrylate polymer blended with mica glass beads at a ratio of substantially 70%-90% of the polymer and substantially 30%-10% of the mica glass beads, respectively, by weight. The preferable range by weight of the blend is substantially 80% of the polymer to substantially 20% of the mica glass beads. The latter ranges of the polymer and the mica glass beads achieve an extremely low shrink ratio and elasticity, as compared to polypropylene. As the injection molded blended polymer of the open frame-like encapsulation 30 cools, its virtually minimal shrink ratio parallels the almost zero coefficient of expansion of the tempered glass panel 21 . Consequently, weld lines of the injection molded frame-like encapsulation 30 will not fracture, particularly when subject to temperature anywhere between −30° F. to 140° F.
[0024] The open frame-like encapsulation 30 includes an outer peripheral portion 31 and an inner peripheral portion 32 with the inner peripheral portion 32 entirely encapsulating the glass panel outer peripheral portion 25 including the peripheral edge 22 and immediately adjacent surface portions of the opposite inner and outer surfaces 23 , 24 , respectively. The frame-like encapsulation 30 further includes an inner or lower surface 34 and an outer or upper surface 35 defining therebetween the overall inner and outer surface configurations of the frame-like encapsulation 30 and the wall thickness thereof. The frame-like encapsulation inner surface 35 is stepped (FIG. 2) at the frame-like inner peripheral portion 32 and defines thereat a relatively thicker wall thickness than the wall thickness at the outer peripheral portion 31 . However, the outer surface 34 has a configuration which is substantially continuous and unstepped which presents an aesthetic appearance to the washer lid 20 when in the closed position (FIG. 1), and all remaining injection-molded characteristics are formed along the inner surface 35 and are hidden from view (FIG. 1) except, of course, when the washer lid 20 is opened (FIG. 2).
[0025] The outer peripheral portion 31 of the washer lid 20 is defined as continuously downward depending peripheral wall or skirt which is smooth and unbroken except along a front edge (unnumbered) of the frame-like encapsulation 30 . At the front edge (FIGS. 1 - 3 ) of the frame-like encapsulation 30 a curved wall portion 38 (FIGS. 2 and 3) of the depending skirt 31 is recessed inwardly and opens concavely outwardly to define a handgrip recess 40 in association with an overlying ledge or lip 39 of the frame-like encapsulation 30 . In order to open the washer lid 20 , a person merely inserts one or more fingers within the handgrip area 40 (FIG. 1) and lifts upwardly against the ledge 39 to pivot the washer lid 20 from the position shown in FIG. 1 to the position shown in FIG. 2.
[0026] The frame-like encapsulation 30 also includes substantially identical corner portions 50 , 50 (FIGS. 1 and 4) defined by the peripheral skirt 31 with a radius (unnumbered) of each corner portion 50 including an elongated curved slot or opening 52 (FIGS. 4 and 5). Two bosses 53 , 54 project inwardly of the peripheral skirt 31 and each includes a respective bore 55 , 56 . Hinge means in the form of a hinge pin 60 is associated with each corner portion 50 and is of a generally L-shaped configuration defined by a pintle portion 61 connected by a radius portion 62 to a mounting portion 63 which includes respective flattened recessed portions 64 , 65 seated upon and receiving therein the bosses 53 , 54 , respectively. Threaded fasteners 64 ′, 65 ′ are fed through bores (unnumbered) of the bosses 53 , 54 and are threaded into threaded openings (unnumbered) of the flattened portions 64 , 65 , respectively, of the mounting portion 63 of each hinge 60 thereby rigidly attaching each of the hinges 60 to the peripheral skirt 31 adjacent an associated one of the rear corner portions 50 . The pintle portions 61 of the hinge pins 60 lie in coaxial relationship to each other and project in opposite directions. Each pintle portion 61 is fitted in one of the openings 15 (FIG. 4) of the inner peripheral wall 14 of the upper frame 13 of the washer body 11 to thereby permit pivoting movement of the washer lid 20 between the positions shown in FIGS. 1 and 2 of the drawings.
[0027] At the corner portion 50 adjacent the hand recess 40 (FIGS. 3, 7, 8 and 9 ), a one-piece molded switch-actuator mechanism 69 defined by a mounting block 70 having a switch actuator leg 71 rests upon four substantially parallel relatively spaced reinforcing ribs 72 which project downwardly from the inner surface 34 of the frame-like encapsulation 30 . The peripheral skirt 31 in the area of the ribs 72 includes two bores 74 through which pass fasteners 75 which are threaded into the mounting block 70 to rigidly secure the same in the manner illustrated in FIGS. 7 through 9 of the drawings. The leg 71 of the switch-actuating mechanism 69 is aligned with the safety “ON”/“OFF” switch 18 to close the latter when the washer lid 20 is closed (FIG. 1) and open the latter when the washer lid 20 is open (FIG. 2) to respectively start and stop the washer agitator (not shown) in a conventional manner.
[0028] A substantially inwardly directed flange 85 is located at each of the front corners 50 , 50 of the washer lid 20 in spaced relationship to the inner surface 34 (FIGS. 3, 7 and 9 ). The flange 85 illustrated at the upper left hand corner 50 of FIG. 3 includes an opening 86 carrying a rubber or similar flexible stop (not shown) which contacts and rests upon the horizontal frame portion 16 of the upper frame 13 of the washer body 11 when the washer lid 20 is in the closed position thereof (FIG. 1). The leg 71 of the switch-actuating mechanism 69 passes through and is radially supported by the opening 86 of the flange 85 (FIGS. 7 and 9).
[0029] As is most readily apparent from FIG. 1 of the drawings, the washer lid 20 presents an extremely aesthetic appearance to the overall washer 10 due to the relatively smooth and unbroken upper/outer surface 35 of the encapsulation 30 . Even in the open position (FIG. 2) of the washer lid 20 , the interior of the washer lid 20 is relatively aesthetic in appearance since the hinges 60 , 60 are unobtrusive, as is the design and location of the switch block 69 which is partially hidden by the flange 85 (FIG. 7). However, most important is the fact that, even though the panel 21 is constructed from glass, the specific blend of the polymer and the mica glass beads from which the frame-like encapsulation 30 is injection molded achieves an intimate bond between the components, absent fracture or weakening of the encapsulation 30 due to the similarities between the low shrink ratios and elasticities of these materials. Since the tempered glass panel 21 has almost a zero coefficient of expansion, there will obviously not be any material of the expansion or contraction of the same relative to the injected polymeric/copolymeric material of the encapsulation 30 at temperatures ranging between −30° F. to −140° F., temperatures which heretofore would cause injection molded polypropylene to fracture. Hence, a strong, durable and aesthetic acceptable washer lid 20 is achieved by the present invention, though usage is as other than a washer lid is well within the breadth of the present disclosure.
[0030] Although a preferred embodiment of the invention has been specifically illustrated and described herein, it is to be understood that minor variations may be made in the apparatus without departing from the spirit and scope of the invention, as defined by the appended claims. | A washer door or lid as defined by a tempered glass panel bordered by an open frame-like encapsulation of one-piece injection molded polymeric/copolymeric synthetic plastic material. The latter material is preferably acrylonitrile/styrene/acrylate polymer blended with mica glass beads at a ratio of substantially 70%-30% to 90%-10% by weight, but preferably 80%-20% by weight. Further specifics of the washer lid include a relatively thick inner periphery of the encapsulation which securely grips and reinforces an outer peripheral edge of the tempered glass panel, a rigid outer peripheral skirt, an indiscrete handle, a reinforced hand corder for a switch actuator and opposite rear corners carrying hinges for securing the washer lid to an associated washer opening. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part under 35 U.S.C §120 of U.S. Ser. No. 13/575,007, filed Jul. 24, 2012 and published on Nov. 22, 2012 as US20120292889 A1, the entire content of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention generally relates to manually driven carrier vehicles, such as carts, hand trucks, dollies, and strollers and, more particularly, to a folding chassis therefor capable of traversing obstacles.
BACKGROUND OF THE INVENTION
[0003] Various manually driven carrier vehicles, for example, hand trucks, carts and strollers, are commonly used for moving objects that are otherwise inconvenient for a person to carry due to size and/or weight, or for transporting infants and toddlers. Often, these carts and strollers have foldable chassis for ease of storage and transportation when not in use. These carriers typically have a telescoping or folding handle, a folding chassis, and wheels set into a predetermined position. Such carts and strollers often have limited capability to traverse rough or uneven terrain because the portability requirement in the folded state limits the range of possible wheel diameters, which, in turn, limits suspension responsiveness. This is because the efforts of moving a cart or a stroller at a given coefficient of friction depend inversely on ratios of wheel to axle diameters and the wheel diameter to height of an obstacle. Other carriers, besides having a telescoping or folding handle and a folding chassis, utilize removable wheels of relatively large size as means to improve terrain trafficability, yet reduce overall dimensions in the folded state. However, removing the wheels requires additional time and complicates handling and storage of the carrier, particularly after use on wet or muddy surfaces.
[0004] Thus, conventional folding carts and strollers, in addition to be able to transport a predetermined load, are designed primarily for convenient handling and portability when folded. However, these known carts and strollers, independently of any trade-offs between the convenience of use and the size in the folded state, are difficult to handle when moving over an irregular terrain, curbs, stairs, and other obstacles. Carrier chassis better capable of dealing with uneven surfaces are inconvenient to store or transport when folded.
[0005] Therefore, it is desirable to provide a folding carrier chassis capable of moving over a rough terrain, including curbs, stairs, and spongy soil. Additionally, it is desirable to have such carrier chassis be foldable relatively flat to provide for ease of storage and transportation. Further, such chassis should preferably be easily folded without disassembling.
SUMMARY OF THE INVENTION
[0006] The present invention relates to a manually driven carrier vehicle having a foldable chassis configured for moving over uneven, soft or spongy surfaces and surmounting obstacles as well as climbing up and down (i.e. “walking”) over curbs, and stairs, that is easy to handle, convenient to use, and folds flat. Particularly, in its various embodiments and implementations, the invention provides for a decreased pressure applied by the chassis onto an underlying terrain, improved stability, decreased pull/push forces especially for moving over the irregular terrain, and improved portability when folded. As a result, when implemented, the carrier according to various embodiments of the present invention facilitates broader participation in outdoor activities by enabling physically handicapped persons to transport their belongings anywhere easily.
[0007] Generally, in one aspect, the invention focuses on a folding chassis that includes a frame having a reference plane, an arm having a first axis and a second axis, said arm being attached rotatable to said frame around the first axis and configured for attaching rotatable, around the second axis, a wheel arrangement having a diameter at least equal to a half of a width of said frame, wherein said arm is configured to pivot between at least a first position and a second position of said wheel arrangement, wherein, in the first position, said wheel arrangement is generally perpendicular to said reference plane and wherein, in the second position, said wheel arrangement is adjacent and parallel to said reference plane.
[0008] In some embodiments, said first axis is positioned at acute angles to said reference plane and to a plane perpendicular to said reference plane. For example, said first axis can be positioned at a first angle to said reference plane in a range from about 15 to 55° and at a second angle to a plane perpendicular to said reference plane in a range from about 30 to 75°.
[0009] In some embodiments, said wheel arrangement includes at least one wheel. In other embodiments, said wheel arrangement includes a plurality of wheels rotatable around axes parallel to said second axis. For example, said plurality of wheels may include three wheels positioned symmetrically relative to said second axis. Also, in various embodiments, said wheel arrangement in the second position is positioned such that it does not exceed a height of said frame.
[0010] In some embodiments, the folding chassis includes a platform configured to pivot from been generally perpendicular to said frame to been generally adjacent and parallel to said frame. Said arm and said platform can be configured to pivot simultaneously from the first position of said wheel arrangement and said platform been generally perpendicular to said frame to said wheel arrangement and said platform been generally adjacent and parallel to said reference plane and said frame respectively. Said arm and said platform can be connected by gear segments.
[0011] In some embodiments, the folding chassis further includes a support pivotally attached to said platform and linked to said frame and said platform, wherein said support configured to pivot between supporting said platform been generally perpendicular to said frame and been generally adjacent and parallel to said platform been generally adjacent and parallel to said frame. For example, said support can be biased to pivot from an intermediate position to one of the end positions.
BRIEF DESCRIPTION OF DRAWINGS
[0012] In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention.
[0013] FIGS. 1A and 1B depict respectively a perspective view of an embodiment of a cart chassis in unfolded state according to present invention and magnified partial view of elements of the chassis.
[0014] FIGS. 2A-2C depict respectively perspective, back, and side views o he embodiment shown in FIG. 1A in a partially folded state.
[0015] FIGS. 3A-3D depict respectively perspective, magnified partial, back, and side views of the embodiment shown in FIG. 1A in a folded state.
[0016] FIG. 4 depicts perspective view of another embodiment of the cart chassis in unfolded state according to present invention.
[0017] FIGS. 5A-5C depict respectively perspective, back, and side views of the embodiment shown in FIG. 4 in a folded state.
[0018] FIG. 6A and 6B depict respectively a perspective view of an embodiment of hand-truck chassis in unfolded state according to present invention and magnified partial view of elements of the chassis.
[0019] FIGS. 7A-7D depict respectively perspective, magnified partial, back, and side views of the embodiment shown in FIG. 6 in a partially folded state.
[0020] FIGS. 8A-8D depict respectively perspective, magnified partial, back, and side views of the embodiment shown in FIG. 6 in a folded state.
[0021] FIG. 9 depicts a perspective view of yet another embodiment of the cart chassis in unfolded state according to present invention.
[0022] FIGS. 10A-10D depict respectively perspective, magnified partial, back, and side views of the embodiment shown in FIG. 9 in a folded state.
DETAILED DESCRIPTION
[0023] In the following detailed description, for purposes of explanation and not limitation, representative embodiments disclosing specific details are set forth in order to provide a thorough understanding of the present teachings. However, it will be apparent to one having ordinary skill in the art having had the benefit of the present disclosure that other embodiments according to the present teachings that depart from the specific details disclosed herein remain within the scope of the appended claims. Moreover, descriptions of well-known apparatuses and methods may be omitted so as to not obscure the description of the representative embodiments. Such methods and apparatuses are clearly within the scope of the present teachings. Set forth for better clarity in symmetrical structures, like reference characters may generally refer to like functioning mirrored parts as well as the same parts.
[0024] Referring to FIGS. 1A-3D , in one embodiment, a generally symmetrical chassis 110 of a cart 100 includes a bridge 111 that supports a telescoping frame 112 with a handle 113 and has knuckles 114 and 115 at its opposite ends. The knuckles 114 and 115 are mirror images of each other and may be integral parts of the bridge 111 or separate components attached thereto. Each of the knuckles 114 and 115 includes an element 117 for pivoting a platform 118 and an element 119 holding axles 120 that are pivoting axes of respectively arms 121 and 122 . The elements 117 and 119 may be holes or pins as integral parts of each of the knuckles 114 and 115 or attached components. The elements 117 are coaxial and the axles 120 in the elements 119 form acute angles with a reference plane (not shown) of the frame 112 , the symmetry plane, and the platform 118 . As used herein, the reference plane is a plane defined by axes of the elements 117 and general proximity to the frame 112 surface. For example, although the frame 112 is shown as a flat structure it may be not so, in which case the reference plane would be a design feature defining dimensions of the cart 100 in the folded state. For a flat frame, the reference plane may be parallel to the frame surface. The angle to the platform 118 as shown in FIGS. 1A and 1B may be in a range from about 30 to about 75°, preferably about 60°, and the angle to the reference plane of the frame 112 may be in a range about from 15 to 55°, preferably about 35°.
[0025] With continued reference to FIGS. 1A-3D , gear segments 123 attached to the platform 118 coaxially with the elements 117 . A support 124 may be hinged at a distal end of the platform 118 . Links 125 may connect the support 124 with levers 126 attached pivotally to the platform 118 and connected to the bridge 111 by links 127 . The links 125 and 127 are connected to the levers 126 pivotally as well. In the unfolded state of the chassis 110 , three pivot axes of the levers 126 and the links 127 are aligned in a straight line that prevents the platform 118 from folding. Springs 128 may be placed between the bridge 111 and the links 127 in such manner that the platform 118 and the support 124 through the links 127 and the levers 126 would be biased from an intermediate position to one of either folded or unfolded positions.
[0026] The arms 121 and 122 are mirror images of each other and each may comprise hinge elements, for example holes, defining an axis of pivoting around the axle 120 , a gear segment 129 meshed with the corresponding gear segment 123 , an element 130 for attaching a wheel arrangement 135 and a catch 131 for engaging the platform 118 in the unfolded position. The element 130 , as an axis of rotation, may be a stationary or rotational axle, a flange or, as shown in this embodiment, a boss with a hole and a latch 132 for a quick disconnect of an axle 133 inserted rotatable through side plates 134 . Multiple wheels 136 may be arranged rotatable between the side plates 134 , constituting a wheel arrangement 135 having a diameter. As used herein, the diameter of the wheel arrangement 135 is understood to mean a diameter of the smallest circle circumscribing the outer reach of the wheels in the wheel arrangement when rotated about the axle 133 . Methods and means of fixing positions of one part relative to another well known in the art so, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function described above.
[0027] In order to fold the chassis 110 , the support 124 is pushed toward the bridge 111 that, through the links 125 , rotates the levers 126 bringing the common pivot of the levers 126 and the links 127 out of alignment and rotates the platform 118 toward the bridge 111 . Rotation of the platform 118 causes rotation of the arms 121 and 122 toward the bridge 111 through gear segments 123 and 129 . In the folded state, the arms 121 and 122 are generally aligned with the bridge 111 with the wheel arrangements 135 positioned side by side and adjacent and parallel to one side of the bridge 111 while the support 124 is generally adjacent and parallel with the platform 118 , which is generally adjacent and parallel to another side of the bridge 111 . It should be noted that the elements 130 with the wheel arrangements 135 relative to the knuckles 114 and 115 may be positioned higher in the folded state than in unfolded.
[0028] Referring to FIGS. 4-50 , in another embodiment, the cart 200 differs from the cart 100 described above in that respect that each of wheel arrangements 201 may consist a single wheel placed on the axle 133 and an optional support extender 202 may be added to the support 124 in order to level the platform 118 .
[0029] Referring to FIGS. 6A-8D , in yet another embodiment of the present invention, a generally symmetrical chassis 310 of a hand truck 300 comprise a bridge 311 that supports a telescoping frame 312 with a handle 313 and has knuckles 314 and 315 at its opposite ends. The knuckles 314 and 315 are mirror images of each other and may be integral parts of the bridge 311 or attached components. Each of the knuckles 314 and 315 comprise an element 317 for pivoting a platform 318 , a rotatable gear segment 323 , and an element 319 holding axles 320 that are pivoting axes of respectively arms 321 and 322 . The elements 317 and 319 may be holes or pins as integral parts of each of the knuckles 314 and 315 or attached components. The elements 317 are coaxial while the axes 320 in the elements 319 form acute angles with a reference plane (not shown) of the frame 312 , the symmetry plane, and the platform 318 . As used herein, the reference plane is a plane defined by axes of the elements 317 and general proximity to the frame 312 surface.
[0030] The angles to the platform 318 as shown in FIGS. 7A and 8B may be in a range from about 30 to about 75°, preferably about 60°, and the angle to the reference plane of the frame 312 may be in a range about from 15 to 55°, preferably about 35°. Positions of the knuckles 314 and 315 relative to the bridge 311 are mirror images of respective positions of the knuckles 114 and 115 relative to the bridge 111 in the previous embodiments.
[0031] The platform 318 includes rockers 324 with cam followers 325 positioned symmetrically and configured to engage slotted levers 328 attached to the gear segments 323 . The rockers 324 are attached to extensions 326 with stoppers 327 , which may interact with the knuckles 314 and 315 and the arms 321 and 322 respectively.
[0032] The arms 321 and 322 are mirror images of each other and each may include hinge elements, for example holes, defining an axis of pivoting around the axle 320 , a gear segment 329 meshed with the corresponding gear segment 323 , an element 330 for attaching a wheel arrangement 335 , and a stopper 331 for engaging the frame 312 in the unfolded position. The element 330 , as an axis of rotation, may be a stationary or rotational axle, a flange or, as shown in this embodiment, a boss with a hole and a latch (not shown) for a quick disconnect of an axle 333 inserted rotatable through side plates 334 . Multiple wheels 336 may he placed rotatable between the side plates 334 . A diameter of the wheel arrangement 335 is understood to mean a diameter of the smallest circle circumscribing the outer reach of the wheels in the wheel arrangement when rotated about the axle 333 . Methods and means of fixing positions of one part relative to another well known in the art so, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function described above.
[0033] In the unfolded position, the elements 317 may stop extensions 326 that limits pivoting of the platform 318 to being generally perpendicular to the frame 312 , and, with the elements 330 generally coaxial, the arms 321 and 322 are set between the stoppers 327 of the platform 318 from one side and the frame 312 from another. In order to fold the chassis 310 , the platform 318 is rotated toward the frame 312 . Rotation of the platform 318 causes rotation of the arms 321 and 322 toward the bridge 311 through the cam followers 325 , the levers 328 and the gear segments 323 and 329 . In the folded state, the arms 321 and 322 are generally aligned with the bridge 311 with the wheel arrangements 335 positioned side by side and adjacent and parallel to one side of the bridge 311 while the platform 318 is generally adjacent and parallel to another side of the bridge 311 . It should be noted that the elements 330 with the wheel arrangements 335 positioned relative to the knuckles 314 and 315 lower in the folded state than in unfolded.
[0034] Referring to FIGS. 9-10D , in yet another embodiment of the present invention, a generally symmetrical chassis 410 of a cart 400 includes a frame 412 with a handle 413 and has knuckles 414 and 415 at its opposite ends. The knuckles 414 and 415 are mirror images of each other and may be integral parts of the frame 412 or attached components. Each of the knuckles 414 and 415 includes an element 417 for pivoting a platform 418 and an element 419 holding axles 420 that are pivoting axes of respectively arms 421 and 422 . The elements 417 and 419 may be holes or pins as integral parts of each of the knuckles 414 and 415 or attached components. The elements 417 are coaxial and the axles 420 in the elements 419 form acute angles with a reference plane (not shown) of the frame 412 , the symmetry plane, and the platform 418 . As explained previously with reference to FIGS. 1A-3C , as used herein, the reference plane is a plane defined by axes of the elements 417 and general proximity to the frame 412 surface. The angles to the platform 418 as shown in FIGS. 10A -10D may be in a range from about 30 to about 75°, preferably about 60°, and the angle to the reference plane of the frame 412 may be in a range about from 15 to 55°, preferably about 35°.
[0035] Gear segments 423 attached to the platform 418 coaxially with the elements 417 . A support 424 may be attached pivotally to the platform 418 and to links 425 that as well attached pivotally to the frame 412 . In the unfolded state of the chassis 410 , three pivot axes of the support 424 and the links 425 are aligned in a straight line that prevents the platform 418 from folding. The platform 418 may be biased from an intermediate position to one of either folded or unfolded positions through the support 424 and/or the links 425 .
[0036] Links 426 attached pivotally to the frame 412 and the handle 413 define positioning of the handle 413 while a latch 427 may lock the handle 413 in unfolded state.
[0037] The arms 421 and 422 are mirror images of each other and each may comprise hinge elements, for example holes, defining an axis of pivoting around the axle 420 , a gear segment 429 meshed with corresponding gear segment 423 , an element 430 for attaching a wheel arrangement 435 , and a catch 431 for engaging the platform 418 in the unfolded position. The element 430 , as an axis of rotation, may be a stationary or rotational axle, a flange or, as shown in this embodiment, a boss with a hole and a latch (not shown) for a quick disconnect of an axle 433 inserted rotatable through side plates 434 . Multiple wheels 436 may be arranged rotatable between the side plates 434 , constituting a wheel arrangement 435 having a diameter. As used herein, the diameter of the wheel arrangement 435 is understood to mean a diameter of the smallest circle circumscribing the outer reach of the wheels in the wheel arrangement when rotated about the axle 433 . Methods and means of fixing positions of one part relative to another well known in the art so, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function described above.
[0038] In order to fold the chassis 410 , the support 424 is pushed toward the frame 412 , which rotates the link 425 bringing the pivot axes of the support 424 and the links 425 out of alignment, and rotates the platform 418 toward the frame 412 . Rotation of the platform 118 causes rotation of the arms 421 and 422 toward the frame 412 through gear segments 423 and 429 . In the folded state, the arms 421 and 422 are generally aligned with the frame 412 with the wheel hubs 435 positioned side by side and adjacent and parallel to one side of the frame 412 while the support 424 may be generally adjacent to the platform 118 , which may be generally adjacent and parallel to another side of the frame 412 . It should be noted that, relative to the knuckles 414 and 415 , the elements 430 with the wheel hubs 435 may be positioned higher in the folded state than in unfolded. Following unlatching the latch 427 , the handle 413 may be rotated about 180° with the links 426 rotated about 270° to overlap the platform 418 .
[0039] Consequently, in its various embodiments, the present invention provides the versatile folding chassis for easily moving over all kinds of terrain, traversing curbs, as well as ascending or descending stairs. Furthermore, the invention provides that such chassis folds relatively flat for better handling and storage in the folded state.
[0040] While several inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the inventive teachings is/are used. For example, a removable track may be fitted over the wheels 151 of each of the hubs 150 for moving over a sandy or spongy terrain. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto; inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.
[0041] Accordingly, as indicated above, the foregoing embodiments of the invention are examples and can be varied in many ways. Such present or future variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be apparent to one skilled in the art are intended to be included within the scope of the following claims.
[0042] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms. | Disclosed is a folding chassis of manually driven carrier vehicles, for example, hand trucks, carts, and strollers, capable of moving over uneven, soft or spongy surfaces and surmounting obstacles. The chassis includes a frame having a reference plane and an arm having a first axis and a second axis, said arm being attached rotatable around the first axis to said frame and configured for attaching rotatable, around the second axis, a wheel arrangement having a diameter at least equal to a half of a width of said frame. Said arm is configured to pivot between at least a first and a second positions of said wheel arrangement, wherein, in the first position, said wheel arrangement is generally perpendicular to said reference plane and wherein, in the second position, said wheel arrangement is adjacent and parallel to said reference plane. | 1 |
[0001] This invention relates to a heating system for a liquid conveyor system, particularly for a urea supply system of a catalytic converter of an internal combustion engine.
[0002] A catalytic converter requires urea as ammonia supplier. Motor vehicles accordingly have a urea tank as a standard in which urea solution is stored for the catalytic converter. In frosty weather, the urea solution can freeze up so that a heating system is required to defrost the urea solution as quickly as possible so that the urea required for catalytic converter operation can be made available.
[0003] It is the objective of the invention to show an economical way of how a catalytic converter of an internal combustion engine can be put faster into working condition at temperatures below freezing.
[0004] This problem is solved by a heating system for a liquid conveyor system, particularly for a urea supply system of a catalytic converter of an internal combustion engine, comprising at least one first heater for defrosting a liquid, and at least one filter heater for heating a filter for liquid filtering; the filter heater is formed by a heating section—designed as a resistance heating element—of an electrical connecting line of the first heater.
[0005] The first heater may be, for example, a tank heater for heating a liquid tank and/or a pump heater for heating a conveyor pump of the liquid conveyor system. It is preferred in any case that the heat output of the first heater is higher than the heat output of the filter heater. It is possible here that the liquid conveyor system comprises a plurality of first heaters—for example, one tank heater and one pump heater—and/or a plurality of filters with filter heaters. In that case, it is generally favorable that the heat output of the first heaters is selected respectively higher than the heat outputs of the filter heater or filter heaters.
[0006] It was found within the scope of the invention that, even when a pump and/or a tank heater is used, a fairly long time can frequently pass until liquid urea solution can be provided to a catalytic converter since the urea ice particularly contained in a urea filter defrosts only slowly. In this respect, a heating system according to the invention can provide an extremely economical remedy since the filter is heated with a filter heater formed by a connecting line—designed as a resistance heating element—of the first heater designed as a tank or pump heater. The costs of a separate heater insert for the filter can thus be saved, and no additional connecting lines for the filter heater are required.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Additional details and advantages of the invention are explained on the basis of exemplary embodiments with reference to the enclosed drawings. Identical and corresponding components are partly designated with matching reference symbols. The features described in the following can be used individually or in combination to create preferred embodiments of the invention. In the Figures:
[0008] FIG. 1 shows a schematic presentation of an exemplary embodiment of a heating system according to the invention;
[0009] FIG. 2 shows a schematic presentation of another exemplary embodiment of a heating system according to the invention; and
[0010] FIG. 3 shows a schematic presentation of a urea supply system with another exemplary embodiment of a heating system according to the invention.
DETAILED DESCRIPTION
[0011] FIG. 1 shows a section of a urea supply system for a catalytic converter of a motor vehicle. The system comprises a dual urea tank in which a first part comprises an only indirectly heated storage tank 1 and a second part a defrosting vessel 3 heated by the tank heater 4 . In the exemplary embodiment shown, the defrosting vessel 3 is provided within the storage tank 1 ; however, it can basically also be provided outside. A one-piece design is also possible in which the storage tank 1 is directly heated.
[0012] The heating system shown in FIG. 1 concerns an insert 11 for a storage tank 1 of a motor vehicle. The insert 11 comprises a defrosting vessel 3 for fast defrosting of a part of the urea volume stored in the storage tank 1 ; also, a filter housing in the form of a filter cup 5 . 1 for the reception of a filter element 5 . 2 , a tank heater 4 for defrosting urea ice in the defrosting vessel 3 , and connecting lines 12 , 13 by means of which a heating current can be conducted through a PTC heating element (not shown) included in the tank heater 4 .
[0013] The filter 5 is heatable by means of a filter heater 14 which is formed by a heating section of the connecting line 12 , the heating section being designed as a resistance heating element. The same heating current thus always flows through the filter heater 14 as well as through the tank heater 4 . Consequently, the PTC heating element of the tank heater 4 automatically limits the heat output of the tank heater 4 as well as of the filter heater 14 , and overheating is impossible since PTC heating elements (positive temperature coefficient) show a sudden increase in their electric resistance when a threshold temperature is exceeded.
[0014] The heating section 14 is formed by a resistance wire, preferably of a heating conductor alloy, for example an FeCrAl alloy. The use of a polymer resistance material is also possible—a PTC polymer, in particular. The resistance wire used has an electric resistance of at least 0.2 Ωmm 2 /m, preferably at least 0.6 Ωmm 2 /m, particularly preferable at least 1.2 Ωmm 2 /m, in the exemplary embodiment shown of 1.44 Ωmm 2 /m. The heating section 14 is embedded by extrusion in the filter cup 5 . 1 made of plastic by injection molding, preferably in its bottom, and it is arranged in a plurality of windings, preferably in a meandering or coil form. Also possible is a resistance heating element in the form of interlacing of a resistance material.
[0015] In the heating system 11 shown, the filter cup 5 . 1 is connected with a tank cover for the defrosting vessel 3 . A preferred one-piece design can do without a sealing point between tank cover and filter cup. It is here particularly advantageous when filter cup 5 . 1 and defrosting vessel 3 form a unit, according to FIG. 1 , which is inserted in the storage tank 1 and thereby closes an opening of the storage tank 1 .
[0016] The insert 11 is part of a urea supply system which comprises, aside from the storage tank 1 , a pump 6 including pressure control and valve by means of which urea solution can be pumped via the intake lines 2 and 10 through the filter 5 via the connecting line 15 into the supply line 7 leading to the catalytic converter. In frosty weather, urea solution contained in the defrosting vessel 3 is first defrosted and then pumped via the intake line 10 into the filter 5 and from there to the connecting line 7 . The capacity of the defrosting vessel 3 is dimensioned such that the urea solution contained therein is sufficient to start up a catalytic converter. After the urea solution in the defrosting vessel 3 has been completely defrosted, the heat generated by the tank heater 4 is also automatically supplied to urea solution outside of the defrosting vessel 3 and thus the entire contents of the storage tank 1 is defrosted so that urea solution can be pumped through the intake line 2 into the filter 5 .
[0017] To support the defrosting process in the defrosting vessel 3 , the defrosted urea solution can be returned via the return line 8 into the defrosting vessel 3 so that the heat generated by the heater 4 is distributed better in the defrosting vessel 3 . Furthermore, the liquid passage opening 9 forms an overflow so that an excess of heated urea solution can escape from the defrosting vessel 3 and get into the surrounding interior space of the tank 1 .
[0018] The intake line 10 is a plastic tube which passes as an intake duct through the tank heater 4 . Preferably, the intake line 10 is also heatable so that the urea solution frozen therein can be quickly defrosted. In the exemplary embodiment shown in FIG. 1 , intake line heating is realized such that, closely adjacent to the intake line 10 , the connecting line 12 is provided and, in the corresponding section, it is also designed as a resistance heating element, particularly as a resistance wire. The connecting line 12 thus has a thermoconducting connection with the intake line 10 so that heat generated by the connecting line 12 can be used for defrosting urea solution in the intake line 10 . The connecting line 12 may be adjacent to the intake line 10 or be coiled around it. A series connection is thus provided of tank heater 4 , filter heater 14 and intake line heating. Due to the self-regulating effect of the PTC heating element of the tank heater 4 , the filter heater 14 as well as the intake line heating are accordingly protected against overheating.
[0019] In the exemplary embodiment shown, only the connecting line 12 is designed as a resistance heating element. Yet, it is also possible to design the connecting line 13 as a resistance heating element as well to thus heat the intake line 10 and/or the filter 5 therewith. For example, one section of a connecting line can serve as filter heating and one section of the other connecting line as intake line heating.
[0020] The exemplary embodiment shown in FIG. 2 essentially differs from the exemplary embodiment described on the basis of FIG. 1 that the intake line 10 —through which urea solution from the defrosting vessel 3 can be drawn into the filter 5 —is designed as a thin stainless steel tube, preferably of V4A steel, and serves as a resistance heating element. The intake line 10 thus simultaneously presents the tank heater 4 .
[0021] The intake line 10 is arranged in the defrosting vessel 3 in a plurality of windings, preferably spiraling or meandering windings, and projects at its upper end with one also preferably coiled section into the filter 5 . The specific resistance of the metal tube forming the intake line 10 is preferably at least 0.2 Ωmm 2 /m, in particular, at least 0.6 Ωmm 2 /m, and 0.75 Ωmm 2 /m in the exemplary embodiment shown.
[0022] When a heating current is conducted through the metal tube forming the intake line 10 , this will result in its heating up and thus in the defrosting of the urea solution surrounding the intake line 10 in the defroster vessel 3 and the filter 5 . The section of the intake tube 10 projecting into the filter here serves not only as a filter heater 14 for heating the filter 5 but also as a connecting line of the tank heater 4 . The metal tube forming the intake line 10 may be designed in one piece or may have a plurality of sections connected by couplings, for example plug-in couplings; said sections may be different in design with regard to material and diameter.
[0023] To avoid overheating of the intake tube 10 , a temperature sensor 16 is provided in a thermoconducting connection to the intake tube, preferably fastened on the intake tube. It is particularly favorable to provide the temperature sensor 16 underneath the filter 5 since no urea solution generally surrounds the intake tube 10 there and the risk of overheating is therefore the highest. In case of overheating, the plastic of the filter cup 5 . 2 and the sealing point at the passage of the intake tube 10 might be damaged.
[0024] For both exemplary embodiments, it is favorable during operation when a heat output of approx. 10 to 30 watt is released by the filter heater, and a heat output of at least 50 watt, preferably 70 watt to 150 watt, by the tank heater.
[0025] To be able to supply liquid urea solution even faster to a catalytic converter, the heating system described can be integrated into a urea supply system in which the supply line 7 and/or the connecting line 15 are also heated. Such line heating can be particularly favorably effected such that corrosion-resistant metal tubes, preferably of stainless steel, are used for the corresponding lines through which a heating current is conducted for defrosting the urea solution so that the metal tubes heat up as resistance heating elements.
[0026] FIG. 3 is a schematic presentation of a urea supply system for a catalytic converter of a motor vehicle. The urea supply system comprises as a first part a urea tank 1 with a filter which are heated by a heating system essentially corresponding to the heating system described on the basis of FIG. 1 . The heating system of the first part is the tank heater 4 as the first heater for defrosting liquid.
[0027] The urea supply system shown in FIG. 3 comprises as a second part a conveyor module 20 by means of which urea solution can be pumped from the urea tank 1 , 3 to a catalytic converter 30 . The conveyor module 20 includes a conveyor pump 21 and a heating system which comprises, as a first heater, a conveyor module heater 25 and additionally a filter heater 28 for heating a filter 24 belonging to the conveyor module. The conveyor module 20 furthermore comprises a dosing valve 22 which is preferably heated, same as the pump 21 , by the conveyor module heater 25 . By means of the dosing valve 22 , the urea solution supplied via the connecting line 7 is distributed to the supply line 32 leading from the filter 24 to the injection nozzle 29 of the catalyzer 30 , and to a return line 31 leading to the urea tank 1 , 3 .
[0028] As another component, the conveyor module 20 comprises a control unit 23 which can control, for example, the pump 21 , the dosing valve 22 , as well as the heating system.
[0029] The most important function of the conveyor module heater 25 is the defrosting of liquid in the pump 21 in frost conditions so that the conveyor module heater 25 is a pump heater in the exemplary embodiment shown. The conveyor module heater 25 preferably contains a PTC heating element and can be provided, for example, in a housing of the pump 21 or of the conveyor module 20 . In the schematic presentation of FIG. 3 , the conveyor module heater 25 seems to be provided at a considerable distance from the conveyor pump 21 . This schematic presentation has been chosen for better clarity; however, in this respect, it does not correspond with the actual conditions. The conveyor module heater 25 is preferably provided close to the conveyor pump 21 and has a good thermoconducting connection with the conveyor pump 21 via thermal bridges. Suitable thermal bridges can be particularly formed by housing parts.
[0030] The filter heater 28 is designed like the filter heaters 14 of the exemplary embodiments described on the basis of FIGS. 1 and 2 . The filter heater 28 is thus formed by a heating section—designed as a resistance heating element—of the connecting line 26 of the conveyor module heater 25 . Reference is also made to the corresponding description of FIG. 1 with regard to further details, for example in terms of the preferred materials or the arrangement of the heating section. Like the filter in the exemplary embodiment explained in the preceding part, the filter 24 preferably comprises a filter housing—for example, a filter cup—in which the filter heater 28 can be embedded.
[0031] It is particularly advantageous to design not only the heating section—forming the filter heater 28 —of the connecting line 26 of the conveyor module heater 25 from resistance wire but to use such resistance wire for the complete connecting line 26 of the conveyor module 20 . Accordingly, in the exemplary embodiments shown, the connecting line 12 , 26 is formed by a resistance wire which extends up to the first heater 4 , 25 . The heater section of the connecting line 12 , 26 forming the filter heater 14 , 28 comprises windings so that the major part of the connecting line 12 , 26 is provided in the filter 5 , 24 and, consequently, the heat output released by the connecting line is released for the major part in the filter 5 , 24 .
[0032] The maximum power of the conveyor module heater 25 amounts to approx. 30 to 40 W in operation; the maximum power of the filter heater 28 to approx. 20 W to 40 W. At temperatures below freezing, the electric resistance of the first heater 4 , is preferably higher than the electric resistance of the filter heater 14 , 28 . | The invention relates to a heating system for a liquid conveyor system, particularly for a urea supply system of a catalytic converter of an internal combustion engine, comprising at least one first heater ( 4 ) for defrosting a liquid, and at least one filter heater ( 14 ) for heating a filter ( 5 ) for liquid filtering, wherein the filter heater ( 14 ) is formed by a heating section—designed as a resistance heating element—of an electrical connecting line ( 12 ) of the first heater ( 4 ). | 1 |
CROSS REFERENCE TO RELATED APPLICATION
This application is related to U.S. Ser. No. 539,607 filed concurrently herewith and entitled "METHOD FOR CONNECTING TWO PARTS WHICH CANNOT BE DIRECTLY WELDED TOGETHER".
FIELD OF THE INVENTION
This invention relates to a heat exchanger and, more particularly, to a heat exchanger which includes a member or wall of steel plate which can be hollow and have a cavity for guiding a liquid heat carrier medium, and at least one heat-conducting baffle plate which is heat-conductively connected to the steel member and projects therefrom.
BACKGROUND OF THE INVENTION
Such heat exchangers have the advantage that the heat-emitting surface area in a heating element (or the heat-absorbing surface area in an absorber of a heat pump) is substantially increased in comparison with a heat exchanger which includes only the steel wall or hollow member. The effect of the heat baffle plate increases as the heat flow in the member increases. This heat flow depends on one hand on the specific heat conductivity and on the other hand on the cross section of the member.
In a conventional heat exchanger of the above-mentioned type, the heat baffle plate is made of steel. The use of a steel baffle plate evolved because the manufacture of a heat-conducting connection can be created very inexpensively by directly welding together the heat baffle plate and the steel member. Of course, the efficiency of heat baffle plates of steel is limited because of the relatively poor heat conductivity of this material, and because for weight and cost reasons the heat baffle plate can only be of a moderate thickness and heat conduction is proportional to the sheet-metal plate thickness.
A basic purpose of the invention is to provide a heat exchanger of the above-mentioned type in which the efficiency of the heat baffle plate is substantially increased for a given plate thickness. In a further development of the basic thought of the invention, advantageous heat-conducting connections between the steel member and the heat baffle plate are provided.
SUMMARY OF THE INVENTION
This purpose is attained according to the invention by providing a heat exchanger of the foregoing type in which the heat baffle plate is made of a metal having a heat conductivity which is greater than the heat conductivity of steel, the heat baffle plate being either soldered to the steel member or held against the steel member by means of a member which is welded to the steel member.
The specific heat conductivity of common steel is approximately 40 W/mK (wherein W is in watts, m is in meters and K is in degrees Kelvin), and of rust-free fine steel only approximately 15 W/mK, while the specific conductivity of aluminum is approximately 200 W/mK, or in other words about five times the specific heat conductivity of common steel. This means that, for a given plate thickness, an aluminum plate will carry five times the heat that a steel plate will. Through this, the efficiency of the heat baffle plate is substantially increased, and therewith the efficiency of the heat exchanger. The combination of a wall of steel and a heat baffle plate of aluminum is also not a problem with respect to corrosion. It is true that aluminum and steel lie apart in the electrochemical series of the metals, but this is not a problem because an electrolyte is not as a rule present between the steel member and the heat baffle plate. Should an electrolyte appear at times in the case of an unfavorable installation, for example in the form of sweat, then this is by no means a danger for the fluid tightness of a hollow steel member, since the aluminum will be sacrificed and thus at most the aluminum baffle plate becomes corroded, but not the hollow steel member. The inventive combination is also advantageous when compared with known heating elements of aluminum, since the heating water comes into contact only with the hollow steel member and therefore steel pipes and also copper pipes can be connected directly to the heat exchanger. The interpositioning of plastic sections in the line to be connected, as is necessary in consideration of corrosion when using aluminum heat exchangers, is thus not needed when using the inventive heat exchanger. The invention also makes it possible to construct the heat baffle plate substantially longer than is sensible when using a steel baffle plate, because larger amounts of heat can be transported to regions of the baffle plate which are remote from the point of contact with the steel member, so that there still exist temperature differences with respect to the surrounding air which permit a significant heat exchange. The invention is not limited to the use of aluminum as a good heat-conducting material. Other metals with good heat conductivity can also be used, in particular many aluminum alloys and copper.
According to a further development of the invention, a steel plate engages the baffle plate, which steel plate in places extends through openings in the baffle plate and is there welded to the steel member. With this connecting technique, it is possible to utilize a very advantageous and inexpensive welding method, even though aluminum and other well heat-conducting materials cannot themselves be welded to steel. Exact alignment of the steel plate can be made substantially easier through the provision of cooperating structural parts on the steel plate and the heat baffle plate.
Prepunched holes in the heat baffle plate have the advantage that a joining by casting of the heat baffle plate is not needed and a particularly long lasting connection between the steel plate and the steel member can be created. In particular, when the steel plate is indented by a welding electrode, one achieves, even in the case of large tolerances for the hole diameters and spacings, a fixed and thus good heat-conducting engagement of the heat baffle plate with the steel member. The heat baffle plate can also be melted to create the openings, through which the advantage is obtained that the steel plate which is placed thereon has a particularly intensive and secure contact with the heat baffle plate, and through which also a particularly good heat transfer from the steel member to the heat baffle plate is achieved. When the openings in the heat baffle plate are to be created by melting during welding, the melting point of the baffle plate must be lower (at least 50° C. lower) than the melting point of steel. This condition is met by aluminum and aluminum alloys. The melting of openings in the heat baffle plate can be achieved without an additional operation if welding electrodes are used for this and, after the melting through, also effect the welding of the steel plate to the steel member. In other types of fastening, the melting point of the heat baffle plate can be higher, for example higher than the melting point of steel. The steel plate preferably has approximately the same thickness as the heat baffle plate. In another embodiment, the steel plate is not needed, for which reason this embodiment is particularly inexpensive. Here too, it is possible to use welding electrodes both for melting openings through the heat baffle plate and for creating the subsequent weld. According to a further feature, a steel holding plate is provided between the steel member and the heat baffle plate. This can then be connected in the usual manner to the steel member by welding, for example spot welding, and can have a particularly favorable surface for facilitating fastening of the heat baffle plate thereon.
According to a further development of the invention, the heat baffle plate is supported by a form-locking engagement thereof with recesses provided in the steel wall or in the holding plate which is welded to said steel member. This connection is also possible despite the fact that aluminum and steel cannot be welded together. Particularly advantageous in this type of connection is the use of the holding plate. The holding plate can easily be changed to have a shape which is suited for fastening the heat baffle plate thereto. The holding plate can be connected to the hollow member by spot welding. It can in general be more easily provided with a shape which is suited for the mounting of the heat baffle plate than is possible with the steel member itself. The heat transfer occurs in this case from the steel member to the holding plate and then to the heat baffle plate. In particular, the holding plate also has a heat-conducting function.
The heat baffle plate preferably has no surface coating. This is possible because aluminum is corrosion-resistant even without a surface coating. This is advantageous for the heat exchange with the surroundings, since the heat-conductivity resistance which a surface coating usually produces does not exist.
Thicknesses of between 0.3 and 0.5 mm give the baffle plate a relatively good physical stability and have a heat conductivity which corresponds with that of a steel plate having a thickness of between 1.5 and 2.5 mm. Because of the high specific conductivity, however, it is also possible to use a baffle plate which is thinner than 0.3 mm. In this case, a protected arrangement of the baffle plate is advantageous in order to avoid deformation thereof.
The inventive heat exchanger can be realized both with several individual heat baffle plates and also with one or more long, bent baffle plates. Because of the good heat conductivity, it can be advantageous in both embodiments to shape each heat baffle plate so that the heat-absorbing or heat-emitting surface area thereon is as large as possible.
A connection of materials which cannot be welded to one another is often possible by soldering. Thus the invention also includes a heat exchanger in which the baffle plate is connected directly to the steel member by a soldering connection and has a better heat conductivity than steel.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention are illustrated in the drawings, in which:
FIG. 1 is a fragmentary perspective view of a heat exchanger which embodies the present invention, including a wall of a hollow steel member with several bent heat baffle plates secured thereon;
FIG. 2 is a fragmentary top view of the heat exchanger according to FIG. 1 showing a bent heat baffle plate;
FIGS. 3 to 6 are fragmentary top views similar to FIG. 2 of respective variations of the heat baffle plate of FIG. 2;
FIG. 7 is a fragmentary sectional top view of the embodiment of FIG. 1 in the region of the fastening of the heat baffle plate on the hollow steel member, showing a steel plate which is placed thereon and has a portion received in a perforation in the heat baffle plate;
FIG. 8 is a fragmentary sectional top view similar to and showing a variation of FIG. 7, during the manufacture of which openings are melted through the heat baffle plate;
FIG. 9 is a fragmentary sectional top view similar to and showing a variation of FIG. 7, in which the fastening of the heat baffle plate is effected by means of embedded steel particles;
FIG. 10 is a perspective view of an alternative embodiment of the heat exchanger of FIG. 1, in which a long, bent metal plate is used as the baffle plate;
FIG. 11 is a fragmentary sectional top view of the heat exchanger of FIG. 10 prior to the fastening of the heat baffle plate to the hollow steel member;
FIG. 12 is a fragmentary sectional top view similar to FIG. 11 and showing the completed fastening of the heat baffle plate to the hollow steel member;
FIG. 13 is a fragmentary sectional end view of the heat exchanger according to FIG. 10 prior to the fastening (and thus corresponds to FIG. 11);
FIG. 14 is a fragmentary sectional end view of the heat exchanger of FIG. 10 after the fastening (and thus corresponds to FIG. 12);
FIG. 15 is a fragmentary sectional top view of a further alternative embodiment of the heat exchanger of FIG. 1, in which different height baffle plates are illustrated;
FIG. 16 is a fragmentary sectional top view of a heat exchanger with two hollow steel members and long, bent heat baffle plates which are secured on the hollow steel members;
FIG. 17 is a fragmentary sectional top view of a further embodiment of the heat exchanger of FIG. 1, in which the heat baffle plate is supported by form-locking engagement thereof with a holding plate provided on the hollow steel member;
FIG. 18 is a fragmentary sectional top view similar to FIG. 17 of a further embodiment in which a connection to a holding plate according to FIGS. 7 to 13 is provided;
FIG. 19 is a fragmentary sectional top view similar to FIG. 7, which shows a heat baffle plate connected to a steel wall by a soldering connection; and
FIG. 20 is a fragmentary sectional top view similar to FIG. 19, illustrating a soldering point which is localized by embossing of the heat baffle plate.
DETAILED DESCRIPTION
The heat exchanger according to FIG. 1 has a hollow steel member 1 and heat baffle plates 2 which are connected heat-conductingly with the hollow steel member 1. The heat baffle plates 2 are bent to be L-shaped, as is illustrated in FIG. 2. The hollow member 1 is made of steel and can, for example, include two cuplike parts which are welded together at their edges, similar to the parts 26 and 27 shown in FIGS. 13 and 14. The heat baffle plates 2 are made of a different material having a heat conductivity which is greater than the heat conductivity of steel. Particularly well suited for this are aluminum and aluminum alloys. It is assumed hereinafter that, in the illustrated exemplary embodiments, heat baffle plates of aluminum are used. Aluminum and steel, as is known, cannot be welded together. In order to create therebetween a good heat-conducting connection, the following constructions are therefore used.
In FIGS. 1 and 2, each heat baffle plate has a leg 2a which is parallel to the hollow steel member 1 and a leg 2b which projects from the hollow steel member 1 perpendicular thereto. As shown in FIG. 7, the leg 2a has holes 3 therethrough. A sheet-metal strip 4 rests on the side of the leg 2a remote from the steel member 1. The sheet-metal strip 4 is a steel plate and has, in the region of each hole 3, a depression 5 which on the other side of the plate forms a boss which projects through the associated hole 3 and is connected to the hollow steel member 1 by spot-welding. The welding zone is identified with reference numeral 6.
The leg 2a is fixedly secured to and pressed against the hollow steel member 1 by the steel plate 4, and in this manner a good heat-conducting connection is created. The welding is done by means of conventional spot-welding electrodes 7 and 8 which are movable toward and away from each other and, during the welding, contact the hollow member 1 and plate 4.
The electrodes 7, 8 are illustrated in the pulled-back condition in FIG. 7. During the welding operation, the electrode 8 is pressed against the steel plate 4 and the electrode 7 against the hollow steel member 1. The electrode 8 also produces the indentation or depression 5 in the plate 4. Prior to actuation of the electrode 8, the plate 4 is flat in the region of each hole 3 in the leg 2a.
In the embodiment according to FIG. 8, a similar steel plate 4 is used for fastening the leg 2'a of the heat baffle plate to the steel member 1, but prepunched holes in the leg 2'a do not exist here. The plate 4 is connected to the steel wall of the hollow member 1 by causing the leg 2'a to have a hole melted through it at the welding point during the welding. In particular, a hole 9 is created, the wall 9a of which is not cylindrical, but has approximately the shape of a cone frustum. The sheet-metal strip 4 is here too indented or depressed (at 10), but the indentation is flatter. Since the formation of the hole 9 is done by melting, one obtains a hole wall 9a which conforms to the shape of the indentation 10, through which a particularly intensive and secure contact is created. The actual welding point is identified here with reference numeral 11. To create the weld, spot-welding electrodes 7 and 8 are again used, which are illustrated in FIG. 8 in a slightly pulled-back position.
In the embodiment according to FIG. 9, steel particles 12 are embedded into the leg 2"a of the baffle plate. These steel particles 12 are welded to the steel member 1, for example the wall of a hollow member. During the creation of the weld, the steel particles 12, which can consist of a waste material, are sprinkled over the leg 2"a. By pressing with the electrodes 7 and 8, and by the welding current heating up the material of the heat baffle plate, the baffle plate is softened and the particles 12 are pressed into the soft material. The particles 12 of steel have a substantially higher melting point than the aluminum baffle plate. Finally, at least some of the particles 12 come into contact with the steel member 1, so that a welding together takes place. The welding points are identified here with reference numeral 13. The embodiment according to FIG. 9 has the advantage that special steel plates of the type used in the embodiments according to FIGS. 7 and 8 are not needed.
FIGS. 3 to 6 illustrate further shapes for heat baffle plates. FIG. 3 illustrates a U-shaped heat baffle plate 20, which has a bight or web 20a and spaced, parallel, outwardly projecting legs 20b, 20c. The web 20a can be connected to a hollow steel member in the same ways discussed in connection with FIGS. 7 to 9. FIG. 4 illustrates a heat baffle plate 21 with a flat leg 21a and a sinuously curved leg 21b. The leg 21a can be secured to the steel member 1 in any manner already described. The sinuous shape of the leg 21b results in an enlargement of its surface area, for a given length, in comparison with a straight leg. Due to the good heat conduction in aluminum, such a surface area enlargement is advantageous.
FIG. 5 illustrates a heat baffle plate 22 with a hat-shaped cross section. This differs from the shape according to FIG. 3 in that bent edge portions 22c and 22d are provided at the outer ends of the legs 22a and 22b, which also causes the surface area to be enlarged. FIG. 6 illustrates a heat baffle plate 23 with a fastening leg 23a, a support leg 23b which extends outwardly at a right angle thereto, and a tubular part 23c of rectangular cross section which is provided at the outer end of the leg 23b. This heat baffle plate can also be secured in a manner like the other heat baffle plates. Again, a relatively large surface area is achieved by providing the tubular part 23c.
A heat exchanger illustrated in FIGS. 10 to 14 has, in place of several individual heat baffle plates, a long baffle plate 14 which is bent to a rectangular or squared-off sinuous or S-shape, and is secured on a hollow steel member 15. The fastening of the baffle plate 14 to the member 15 is preferably carried out in the same manner discussed already in connection with FIG. 7.
The heat baffle plate 14 rests with heat-transmitting regions 16 thereof against the hollow member 15. A loop 17 exists between each adjacent pair of such contact regions, which loops give heat off to the surrounding air (in the case of a heating element) or absorb heat from the surrounding air (in the case of a heat absorber). A strip 18 of steel plate rests against each heat-transmitting area 16, which plate 18 during the creation of the connection is pressed through holes which are provided in the heat-transmitting areas 16 of the baffle plate.
FIGS. 11 and 13 illustrate the condition prior to welding. In this condition, the steel-plate strips 18 are still flat. FIGS. 12 and 14 illustrate the condition after the welding. In this respect, FIGS. 12 and 14 correspond to FIG. 7. In order to make proper alignment of the sheet-metal strips 18 with the baffle plate easier, the baffle plate has at every heat-transmitting area 16 a boss or elevation 24 which is aligned with a corresponding recess 25 in the steel plate 18. FIG. 14 illustrates the condition after the welding. It is also possible to press the elevation and recess 24 and 25 flat during the welding. However, this does not have to be done.
The hollow steel member 15 is composed of two cups or parts 26 and 27 which have their outer edges secured to each other. It is stated at this point that the member on which the baffle plate is secured need not necessarily be a hollow member. For example the steel-plate wall, on which the baffle plate is secured could also be electrically heated, for which a hollow member which can carry a flowable heat-carrying medium is not needed.
The height of the baffle plate loops 17 is identified with b in FIG. 11, and the thickness of the baffle plate with a. For a given sheet-metal thickness a, the height b can be substantially greater for an aluminum baffle plate than would be sensible if the baffle plate were made of steel. Because of the substantially better heat conductivity of aluminum, even for a relatively large height b a lot more heat can be conducted into the outer portions of the loops, so that there still exists a significant temperature difference compared with the surrounding air.
FIG. 15 illustrates an embodiment which in most respects corresponds to the embodiment according to FIGS. 10 to 14. FIG. 15 shows that it is possible to secure, on one steel wall 28, baffle plates 29, 30 or 31 having various respective heights h 1 , h 2 and h 3 . Here again, fastening is effected with steel plates 32. The width of the different height baffle plates is the same, so that for all of these baffle plates the same steel wall 28 can be used. The selection of the appropriate baffle plate then occurs according to the particular temperature differences and the desired output of the heat exchanger.
FIG. 16 illustrates another way of bending baffle plates so that a relatively large surface area is achieved. FIG. 16 illustrates walls of two hollow steel members 33 and 34 which have secured on the sides thereof which face one another heat baffle plates 35. The heat baffle plates 35 have heat-transmitting regions 36 which engage the hollow members 33 and 34. These are also secured by means of steel-plate strips 37 which are welded to the associated hollow member. The baffle plates 35 have loops 38 which project outwardly from the hollow steel member between adjacent heat-transmitting regions 36. The loops 38 are formed by bends in the baffle plates 35 which, in the outermost portions thereof, have a rectangular recess 39 which gives them a squared-off S-shape which substantially enlarges their surface area and thus the contact surface for the surrounding air. Also in this manner, the good heat conductivity of aluminum can be fully utilized. This construction is also advantageous if the maximum height of the heat baffle plate is predetermined and a large surface area for the heat baffle plate is desired.
FIG. 18 illustrates an embodiment in which a holding plate 41 of steel is secured on a steel wall 40, to which plate 41 the actual heat baffle plate 42 of aluminum is then connected.
The holding plate 41 has a squared-off S-shape and is connected at fastening regions 43 by means of spot weldings 44 to the steel wall 40. Loops 45 thereof extend outwardly between the fastening areas 43, which loops 45 each have a flat outer wall 45a which is connected to the heat baffle plate 42. The baffle plate 42 is constructed to correspond to FIGS. 10 to 14, and is secured in the same manner by means of steel-plate strips 18. In this embodiment, the holding plate 41 has a heat-conducting function, since it must transmit heat between the steel wall 40 and the heat baffle plate 41. The holding plate 41 also has air circulating around it, so that it can directly give off or absorb heat.
In the embodiment according to FIG. 17, a holding plate 47 is secured on a steel wall 46. The holding plate 47 serves to clamp a heat baffle plate 48. The holding plate 47 has fastening portions 49 which are connected to the steel plate 46 by spot weldings 50. This is possible through the use of the same materials for the parts 46 and 47.
The fastening plate 49 is bent to have spaced recesses or grooves 51 which each have spaced side walls, each side wall being bent to define grooves or undercut sections 52, 53. The heat baffle plate 48 which consists of aluminum has an approximately squared-off S-shape. The portions of the baffle plate 48 adjacent the steel plate 46 have projections 54 and 55 which engage the undercut sections 52 and 53.
The mounting can, for example, be done in such a manner that the heat baffle plate 48 is moved into the grooves 51 in a direction normal to the plane of the drawing. Also, it is possible to effect a deformation such that, for a direction of movement parallel to the plane of the drawing, the portions of the baffle plate adjacent the steel plate 46 can be placed into the grooves. Such a deformation is indicated by the dash-dotted lines 56.
In the embodiment according to FIG. 17, and in the case of heat emission from the steel wall 46, heat is first guided through the holding plate 47. Heat is then guided into the heat baffle plate 48 at the contact points with the holding plate 47 in the region of the grooves 51. To achieve good heat transmission, it is desirable that as much of the heat baffle plate 48 as possible engage without clearance the holding plate 47.
FIGS. 19 and 20 illustrate the manufacture of a heat exchanger in which the heat baffle plate is connected to the steel wall by means of a soldering connection. In FIG. 19, the steel wall is identified with reference numeral 61 and the heat baffle plate with reference numeral 60. The heat which is needed for the soldering is provided by electrodes 7', 8' and is conducted through the sheet-metal plates 60 and 61. A soldered point 64 is thus formed. The size of the soldered point 64 is determined by the shape of the electrode 7', which in this case is of relatively small diameter.
In FIG. 20, the steel wall is identified with reference numeral 63 and the heat baffle plate with reference numeral 62. The heat baffle plate 62 has an indentation or depression 65 in one side thereof at the soldering point, which produces a boss on the opposite side thereof which engages the steel wall 63 prior to the start of the soldering operation. During the creation of the soldering connection, current is conducted through the plates 62, 63 from the electrodes 7", 8' and thus the heat needed for the soldering is produced. The soldering starts in the area of the boss 65 which, during the course of the soldering, is pressed flat so that the heat baffle plate 62 engages the steel plate 63 without any space therebetween. Since in the arrangement according to FIG. 20, the soldering point is localized by the provision of the boss 65, the upper electrode 7" can have a substantially greater diameter than the soldering point.
Although particular preferred embodiments of the invention have been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention. | A heat baffle plate of aluminum or another good heat-conducting metal is secured on a steel member. Since aluminum cannot be welded to steel, connections are utilized which result in a good heat-conducting connection but without direct welding. For example, a steel plate can be placed over a portion of the heat baffle plate and then be welded through openings in the aluminum plate to the steel member. The baffle plate can alternatively be supported by a form-locking engagement with a holding plate of steel which is welded to the steel member. The better heat conductivity of the aluminum baffle plate causes the heat emission or heat absorption to be substantially increased for a given structural arrangement in comparison to a heat baffle plate of steel. | 8 |
[0001] The present application claims priority under 35 U.S.C. §119 to Japanese Patent Applications No. 2009-126126 filed on May 26, 2009, and No. 2010-117169 filed on May 21, 2010. The content of the application is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a vibration actuator and an electric device.
[0004] 2. Description of the Related Art
[0005] There has been a vibration actuator wherein an vibrating element is made to vibrate using an electromechanical conversion element, and a moving element is made to rotate by these vibrations. In such an vibration actuator, a bearing is used in order to hold the moving element so as to be rotatable with respect to the vibrating element (for example, refer to Japanese Unexamined Patent Publication No. Hei 10-319300). Thus far, metal has been used as the material for this bearing.
SUMMARY OF THE INVENTION
[0006] However, when using metal as the bearing material, the cost becomes high, and the weight increases.
[0007] A problem to be solved by the present invention is to provide a vibration actuator which has favorable characteristics.
[0008] The present invention solves the above described problem by the following means.
[0009] According to the first aspect of the present invention, there is provided a vibration actuator comprising: a vibration portion which contacts a relative movement portion, and which produces necessary vibration for a relative movement of the relative movement portion; a first member which is provided so as to hold the relative movement portion between the first member and the vibration portion, and which moves relative to the vibration portion in response to movement of the relative movement portion with respect to the vibration portion; a second member which faces the first member via a rolling member, and which supports the first member so that the first member is movable relative to the vibration portion; and a pressing member which gives rise to a pressing force between the second member and the vibration portion so that the vibration portion and the relative movement portion are in contact with each othercome in contact with each other; and wherein the first member comprises a plastic substance.
[0010] The first member may comprise a connection portion which is capable of connecting to the outside, at an outer circumferential face in a direction of relative movement of the vibration portion and the relative movement portion, and in a direction orthogonal to the direction of the pressing force.
[0011] The connection portion may be a gear which transmits power.
[0012] The relative movement portion and the vibration portion may relatively rotate about a central rotation axis.
[0013] The rolling member may be provided between an outer circumferential face of the second member and an inner circumferential face of the first member.
[0014] The first member may face the second member in a direction of relative movement of the vibration portion and the relative movement portion, and a direction orthogonal to a direction of the pressing force.
[0015] The rolling member may be provided between the first member and the second member, when seen in a direction of the pressing force.
[0016] The vibration actuator may further comprise a vibration absorption member provided between the relative movement portion and the first member when seen in a direction of the pressing force.
[0017] The first member may be made of plastic.
[0018] The second member may comprise a plastic substance.
[0019] The rolling member may be a metal sphere.
[0020] The rolling member may be held by a retainer made of plastic.
[0021] According to the second aspect of the present invention, there is provided an electric device comprising the above mentioned vibration actuator.
[0022] Further, the above constitution may be suitably improved, or at least partially substituted with other constitutional elements.
[0023] According to the present invention, it is possible to provide a vibration actuator and electric device having favorable characteristics.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a conceptual drawing explaining the camera of one embodiment of the present invention;
[0025] FIG. 2 is a longitudinal cross section drawing of an ultrasonic motor;
[0026] FIG. 3 is a longitudinal cross section drawing of an ultrasonic motor according to the second embodiment of the present invention;
[0027] FIG. 4 is an enlarged drawing of the bearing portion in FIG. 3 ; and
[0028] FIG. 5 is a longitudinal cross section drawing of the ultrasonic motor according to the third embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
First Embodiment
[0029] Below, the first embodiment of the present invention will be explained with reference to the drawings and the like. Further, in each of the following drawings, in order to facilitate the explanations and understanding, an XYZ Cartesian coordinate system is established. In this coordinate system, in the position of the camera when photographing an image in the landscape orientation with the photographer making the optical axis A horizontal (below referred to as the normal position), the direction towards the left side as seen by the photographer is the X-plus direction. Further, in the normal position, the upwards direction is the Y-plus direction. Furthermore, in the normal position, the direction towards the subject is the 1-plus direction.
[0030] FIG. 1 is a conceptual drawing explaining the camera 1 of the first embodiment. In the camera 1 of the first embodiment, an ultrasonic motor 10 is provided as an example of the vibration actuator.
[0031] The camera 1 is provided with a camera body 2 having an image sensor 8 , and a lens barrel 3 . The lens barrel 3 is an interchangeable lens which is detachable from the camera body 2 . Further, in the present embodiment, the lens barrel 3 is shown by an example which is an interchangeable lens, but without being limited to this, for example, the lens barrel may be one which is integrated with the camera body.
[0032] The lens barrel 3 is provided with the focusing lens 4 , cam tube 5 , idler gear 6 , ultrasonic motor 10 , and a case body 7 which encases them.
[0033] In the first embodiment, the ultrasonic motor 10 is disposed in the annular space between the cam tube 5 and the case body 7 . The ultrasonic motor 10 is a driving source which drives the focusing lens 4 during the focusing operation of the camera 1 . The ultrasonic motor 10 rotationally drives the cam tube 5 via the idler gear 6 engaged with the output gear 10 G of the ultrasonic motor 10 .
[0034] The cam tube 5 is provided to be movable in a direction parallel to the optical axis OA (Z axis direction) in the case body 7 , by rotational operation by the ultrasonic motor 10 .
[0035] The focusing lens 4 is held at the cam tube 5 . Then, focus point adjustment is carried out by moving in the optical axis OA direction by movement of the cam tube 5 by the driving of the ultrasonic motor 10 .
[0036] Further, while not shown in the drawings, the lens barrel 3 is provided with a plurality of lens groups in addition to the focusing lens 4 .
[0037] In FIG. 1 , a object image is imaged at the imaging face of the image sensor 8 by the lens group including the focusing lens 4 provided in the lens barrel 3 . The imaged object image is converted to an electric signal by the image sensor 8 , and imaging data is obtained by A/D conversion of this signal.
[0038] Next, the ultrasonic motor 10 as the first embodiment is explained in detail with reference to FIG. 2 .
[0039] FIG. 2 is a longitudinal (in the axial direction) cross section drawing of the ultrasonic motor 10 .
[0040] The ultrasonic motor 10 is provided with a support shaft 11 which is disposed to pass through its center, an vibrating element 12 , a rotating body 13 which is rotationally driven by the vibrating element 12 , a support body 14 which supports the vibrating element 12 , and a bearing 20 which supports the rotating body 13 so as to freely rotate. Further, the ultrasonic motor 10 is provided with a pressing spring 15 which pressure-energizes the vibrating element 12 towards the rotating body 13 , and a stopping washer 16 which regulates the position of the pressing spring 15 with respect to the support shaft 11 . In the present embodiment, the vibrating element 12 is a fixed side, and is formed so that does not rotate with respect to the support shaft 11 , while it rotationally drives the rotating body 13 with respect to the support shaft 11 .
[0041] The support shaft 11 is a shaft of a predetermined diameter, and at one end (the Z axis plus side) the flange 11 A having a large diameter is formed. At the other end of the support shaft 11 , the stopping washer 16 is mounted. The stopping washer 16 is provided so as to be unable to move towards the Z axis minus side by engaging with a retaining ring 17 which is an E ring or the like mounted at the outer end side of the support shaft 11 .
[0042] The vibrating element 12 is a member whose overall form is hollow, and is constituted by the elastic body 12 A and the piezoelectric body 12 B which is joined to the elastic body 12 A.
[0043] The elastic body 12 A is formed as a hollow annulus whose outer form is approximately circular, of a metal material having a high degree of resonance acuteness. The elastic body 12 A has a comb tooth portion 12 Aa, a base portion 12 Ab, and a flange portion 12 Ac, and the like.
[0044] The comb tooth portion 12 Aa has a plurality of grooves of a predetermined width in the circumferential direction with a predetermined spacing and to a predetermined depth, formed from a face of the side facing the rotating body 13 of the elastic body 12 A. The front face of the comb tooth portion 12 Aa (the face of the elastic body 12 A which faces the rotating body 13 ) press-contacts the rotating body 13 and is the driving, face 12 Ad which drives the rotating body 13 , and a lubricant surface treatment such as Ni—P (nickel-phosphorous) plating or the like is usually applied thereto. Further, the reason for providing the comb tooth portion 12 Aa is to bring the neutral plane of the progressing wave arising at the driving face 12 Ad by the expansion and contraction of the piezoelectric body 12 B as close as possible to the piezoelectric body 12 B side, an in this way to amplify the amplitude of the progressing wave of the driving face 12 Ad.
[0045] The base portion 12 Ab is the part on the opposite side of the comb tooth portion 12 Aa of the elastic body 12 A (on the Z axis minus side in the drawing) on which the grooves of the comb tooth portion 12 Aa are not formed, and is continuous in the circumferential direction of the elastic body 12 A.
[0046] The flange portion 12 Ac is a portion of a small diameter which protrudes to a predetermined thickness at the inner circumference side of the elastic body 12 A. By this flange body 12 Ac, the vibrating element 12 is supported at the support body 14 .
[0047] The piezoelectric body 12 B has an approximately plate-like shape, and is joined by an adhesive to the face of the base portion 12 Ab side of the elastic body 12 A (the side of the elastic body 12 A at the opposite side to the rotating body 13 ).
[0048] The piezoelectric body 12 B is an electromechanical conversion element which converts electrical energy into mechanical energy. Further, in the present embodiment, a piezoelectric element is used as the piezoelectric body 12 B, but it is also possible to use an electrostrictive element or the like.
[0049] The piezoelectric body 12 B is provided with two electrodes, not shown in the drawing, for inputting a driving signal.
[0050] The flexible printed circuit board 12 C is disposed at the face at the opposite side of the elastic body 12 A of the piezoelectric body 12 B.
[0051] The wiring of the flexible printed circuit board 12 C is connected to the electrodes of the piezoelectric body 12 B.
[0052] The flexible printed circuit board 12 C has the function of providing a driving signal to the piezoelectric body 12 B. Progressing waves are generated at the driving face of the elastic body 12 A when the elastic body 12 A is excited by the expansion and contraction of the piezoelectric body 12 B, by the driving signal provided from this flexible printed circuit board 12 C. In the present embodiment, a four wave progressing wave is generated.
[0053] The rotating body 13 is a member which is rotationally driven by the progressing wave arising at the driving face 12 Ad of the elastic body 12 A.
[0054] The rotating body 13 is formed with an approximately discoid shape of a light metal such as aluminum or the like, and has a contact face 13 A which has an approximately annular shape and contacts the vibrating element 12 (the driving face 12 Ad of the elastic body 12 A), and a joining portion 13 B which has a cylindrical shape with a small diameter and joins to the bearing 20 (outer wheel 22 ). The contact face 13 A is given a surface treatment of alumite or the like to increase the abrasion resistance.
[0055] The joining portion 13 B of the rotating body 13 fits at the joining portion 22 A of the outer wheel 22 of the later described bearing 20 via the damping member 18 and is joined without allowing rotation relative to the outer wheel 22 .
[0056] The support body 14 which supports the vibrating element 12 has a main body portion 14 A of a predetermined outer diameter, a support portion 14 B which fits at the flange portion 12 Ac of the vibrating element 12 , and a pressing flange 14 C having a large diameter, which is formed between the main body portion 14 A and the support portion 14 B and exhibits an approximately discoid shape. Further, a mounting hole 14 D which fits the support shaft 11 so as to be slidably movable is formed at the central portion of the support body 14 .
[0057] The support body 14 fits the support shaft 11 at the mounting hole 14 D, and its support portion 148 fits to the flange portion 12 Ac of the vibrating element 12 , and in this way, the vibrating element 12 is concentrically supported about the support shaft 11 .
[0058] A pressing spring 15 is disposed between the pressing flange 14 C of the support body 14 and the stopping washer 16 mounted at the shaft end of the support shaft 11 .
[0059] The pressure spring 15 is a coil spring which gives rise to an elastic return force by compressive deformation, and it is disposed such that the main body portion 14 A of the support body 14 is fit at its inner circumference. Further, this elastic return force pressure-energizes the pressing flange 14 C (namely the support body 14 ) in a direction away from the stopping washer 16 .
[0060] The bearing 20 is provided with the inner wheel 21 , the outer wheel 22 , and the ball 23 disposed between the inner wheel 21 and the outer wheel 22 , and is constituted to allow free relative rotation between the inner wheel 21 and the outer wheel 22 with low friction by the rolling of the ball 23 .
[0061] The outer wheel 22 is provided with the joining portion 22 A at its inner circumference, which is joined with the rotating body 13 . Further, the output gear 10 G is formed at the outer circumference of the outer wheel 22 . In other words, the outer wheel 22 has the function of supporting the rotating body 13 , and the function of outputting the rotational power of the rotating body 13 to the outside.
[0062] The inner wheel 21 of the bearing 20 is fit to the support shaft 11 without allowing relative rotation, and one end face thereof (the Z axis plus side) abuts the flange 11 A of the support shaft 11 .
[0063] The joining portion 138 of the rotating body 13 is fit to the joining portion 22 A of the outer wheel 22 of the bearing 20 , and joined thereto via the damping member 18 . In this way, the bearing 20 supports the rotating body 13 so as to be freely rotatable. Further, the constitution of this bearing 20 will be explained later in more detail.
[0064] The damping member 18 is a member of approximately annular shape having a predetermined thickness and formed of an elastic body such as rubber or the like.
[0065] The damping member 18 is disposed between the end face of the joining portion 13 B of the rotating body 13 , and the end face of the joining portion 22 A of the outer wheel 22 of the bearing 20 , and joins the two without allowing relative rotation. The damping member 18 has the function of making the rotating body 13 and the outer wheel 22 of the bearing 20 integrally rotatable by its viscoelasticity, and the function of absorbing the vibrations of the rotating body 13 so that they are not transmitted to the outer wheel 22 . The damping member 18 is formed of, for example, butyl rubber, silicon rubber, propylene rubber, and the like.
[0066] In an ultrasonic motor 10 constituted as above, the vibrating element 12 is pressure-energized towards the rotating body 13 by the elastic return force of the pressing spring 15 via the support body 14 , and the driving face 12 Ad is press-contacted to the contact face 13 A by a predetermined force. Then, when two alternating current driving waveforms having different phases are input to the two electrodes of the piezoelectric body 12 B of the vibrating element 12 , a progressing wave is generated at the rotating body 13 side of the elastic body 12 A by the deformation of the piezoelectric body 12 B. The rotating body 13 (contact face 13 A) which press-contacts the vibrating element 12 (driving face 12 Ad) is friction driven to rotate by these progressing waves. The rotations of the rotating body 13 are transmitted to the outer wheel 22 of the bearing 20 via the damping member 18 , and the outer wheel 22 , namely the output gear 10 G, rotates, and the rotational power is output to the outside.
[0067] Next, a more detailed explanation will be given of the bearing 20 of the first embodiment.
[0068] As mentioned above, the bearing 20 is provided with the inner wheel 21 , the outer wheel 22 , and the ball 23 . Further, the bearing 20 is disposed at the right side (Z axis minus side) in FIG. 2 of the flange 11 A with the inner wheel 21 fit to the support shaft 11 without allowing relative rotation, and receives the energizing force (the energizing force which pushes the vibrating element 12 to the rotating body 13 ) of the pressing spring 15 acting via the vibrating element 12 and the rotation body 13 , and supports the rotating body 13 so as to be freely rotatable.
[0069] Namely, at the Z axis minus side of the bearing 20 , the rotating body 13 , the vibrating element 12 , the support body 14 , and the pressing spring 15 are disposed in series in the axial direction of the support shaft 11 , and the pressing force generated from the pressing spring 15 which presses the vibrating element 12 to the rotating body 13 is act on the outer wheel 22 .
[0070] The inner wheel 21 is an annular shape having an inner diameter portion into which the support shaft 11 can fit, and is formed with a predetermined thickness in the radial direction. At its outer circumference, there is formed in the circumferential direction an inner rolling face 21 A where the ball 23 rolls.
[0071] The inner rolling face 21 A is formed with an arc-shaped cross sectional form conforming to the spherical surface of the ball 23 , and has the radial inner face portion 21 Ar which faces the outer side in the radial direction, and the thrust inner face portion 21 As orthogonal to the Z axis and which faces the Z axis minus direction.
[0072] The outer wheel 22 has a shape which is annular in outline, but as explained above, the output gear 10 G is formed at its outer circumference. At the inner circumference of the outer wheel 22 , the joining portion 22 A with which the rotating body 13 is joined, and the outer rolling face 22 B on which the ball 23 rolls, are respectively formed in the circumferential direction.
[0073] The joining portion 22 A has a recessed shape with a circular inner diameter into which the joining portion 13 B of the rotating body 13 can be inserted and fit, and is open at the side where the rotating body 13 of the outer wheel 22 is disposed (the Z axis minus side).
[0074] The outer rolling face 22 B is formed with an arc-shaped cross sectional form conforming to the spherical surface of the ball 23 , and has the radial outer face portion 22 Br which faces the inner side of the radial direction, and the thrust outer face portion 22 Br orthogonal to the Z axis and which faces the Z axis plus side. Namely, the outer wheel 22 is integrally formed with a portion (the joining portion 22 A) which holds the rotating body 13 .
[0075] The ball 23 is a rollable sphere interposed between the inner rolling face 21 A of the inner wheel 21 , and the outer rolling face 22 B of the outer wheel 22 , and a plurality are disposed around the whole circumference between the inner wheel 21 (inner rolling face 21 A) and the outer wheel 22 (outer rolling face 22 B).
[0076] Here, the inner wheel 21 and outer wheel 22 are manufactured of a substance having plasticity, in particular a plastic material which is easily moldable. However, without being limited to this, they may also be, for example, a thermoplastic material, a resin, a celluloid, a high polymer material and the like.
[0077] The inner wheel 21 and the outer wheel 22 are respectively formed by injection molding or the like of a plastic material. As the plastic material, for example, polyacetal, polyether ether ketone, polybutylene terephthalate, polycarbonate and the like may be used.
[0078] On the other hand, the ball 23 is formed of a metal material such as a stainless alloy steel or the like, or a material such as a ceramic or the like. The outer wheel 22 has a lower hardness than the ball 23 , and a higher flexibility than the ball 23 .
[0079] In the bearing 20 with the above constitution, the outer wheel 22 can relatively rotate with respect to the inner wheel 21 mounted and fixed to the support shaft 11 , by the rolling of the balls 23 .
[0080] The power (thrust force Fs) by the energizing of the pressing spring 15 in the Z axis direction via the rotating body 13 , as well as the driving counterforce (radial force Fr) in a direction orthogonal to the rotation axis (=Z axis direction) when the output gear 10 G outputs the rotational power to the outside, act on the outer wheel 22 of the bearing 20 .
[0081] The thrust force Fs acts on the thrust inner face portion 21 As of the inner rolling face 21 A of the inner wheel 21 via the ball 23 , from the thrust outer face portion 22 B of the outer rolling face 22 B of the outer wheel 22 . In this way, the bearing 20 receives the thrust force Fs with the thrust inner face portion 21 As, and the outer wheel 22 is smoothly rotatable.
[0082] Further, the radial force Fr acts on the radial inner face portion 21 Ar of the inner rolling face 21 A of the inner wheel 21 via the ball 23 , from the radial outer face portion 22 Br of the outer rolling face 22 B of the outer wheel 22 . In this way, the bearing 20 receives the radial force Fr at the radial inner face portion 21 Ar, and the outer wheel 22 is smoothly rotatable without eccentricity.
[0083] In this way, the bearing 20 is provided with both functions of a thrust bearing and a radial bearing.
[0084] As described above, the bearing 20 is able to stably and rotatably support the rotating body 13 while resisting the thrust force Fs by the pressing spring 15 acts on the outer wheel 22 via the rotating body 13 . Further, it is able to allow the outer wheel 22 to stably rotate, preventing eccentricity, while resisting the radial force Fr arising when the output gear 10 G engages with and drives the gears of the side of the load to be driven. As a result, it is possible to output to the outside the rotational force with little fluctuation in speed, via the outer wheel (output gear 10 G).
[0085] In the present embodiment, the inner wheel 21 and outer wheel 22 of the bearing 20 are formed of a plastic material. Because of this, the outer wheel 22 and the output gear 10 G can be integrally formed, and can be manufactured at low cost. If the inner wheel 21 and the outer wheel 22 of the present embodiment were, for example, formed of metal as in the conventional manner, gear machining and cutting machining would be necessary, which would incur greatly higher costs. If they were constituted of different materials and assembled, the costs would also increase because of the increased number of parts and assembly stages. This does not occur in the present embodiment. Further, the constitution can be made light. In addition, what the ball 23 contacts is the inner wheel 21 and the outer wheel 22 , which are made of plastic, thus there is no mutual contact of metals, and it is possible to design the bearing 20 to be quiet when operating.
[0086] Further, in the present embodiment, the joining portion 22 A which joins to the rotating body 13 is formed at the inner diameter side of the outer wheel 22 which has the output gear 10 G formed on its outer diameter side. In this way, the overall length of the ultrasonic motor 10 can be shortened. In contrast, if the joining portion 22 A were not provided and the outer wheel 22 and the rotating body 13 were disposed in series, in order to maintain the same tooth width of the output gear 10 G as in the present embodiment, the length of the ultrasonic motor 10 in the axial direction would have to be increased. In the present embodiment, it is possible to compactly constitute an ultrasonic motor 10 having an output gear 10 G with a wide facewidth.
Second Embodiment
[0087] Next, the second embodiment of the present invention will be explained with reference to FIG. 3 and FIG. 4 .
[0088] FIG. 3 is a cross sectional drawing of the ultrasonic motor 110 according to the second embodiment. FIG. 4 is a an enlarged drawing of a portion of the bearing 120 of FIG. 3 .
[0089] The ultrasonic motor 110 shown in FIG. 3 , in the same way as in the first embodiment, is used for an application such as the rotational driving of a cam tube 5 of a lens barrel 3 , but in the present embodiment it is constituted in a ring shape.
[0090] Further, the bearing 120 in the ultrasonic motor 110 of the present embodiment is constituted in approximately the same way as the bearing 20 in the previously described first embodiment, and detailed explanations of identical constituent elements are omitted.
[0091] The ultrasonic motor 110 is provided with a support ring 111 , an vibrating element 112 , a rotating body 113 , a bearing 120 , a pressing portion 115 , and a fixing ring 116 . Further, the ultrasonic motor 110 is provided with the first damping member 112 , the second damping member 119 , and the like.
[0092] The vibrating element 112 is provided with the elastic body 112 A and the piezoelectric body 112 B.
[0093] The elastic body 112 A is a member of approximately annular shape, and at one end face, the piezoelectric body 112 B is provided, and at the other face, the comb tooth portion 112 Aa is formed, wherein a plurality of grooves are cut and formed. A progressing wave is generated by the vibrations of the piezoelectric body 112 E at the tip end faces of the comb tooth portion 112 Aa, which form the driving face 112 Ad which drives the rotating body 113 .
[0094] The piezoelectric body 112 B has the function of converting electrical energy into mechanical energy. This piezoelectric body 1128 has electrodes, not shown in the drawings, which are connected to the flexible printed circuit board, and is excited by driving electric power provided from this flexible printed circuit board.
[0095] The rotating body 113 is member having an approximately annular shape, and has the contact face 113 A having an approximately annular shape and which contacts the vibrating element 112 (the driving face 112 Ad of the elastic body 112 A), and the joining portion 113 B having a cylindrical shape which joins to the bearing 120 (the outer wheel 122 ).
[0096] In the rotating body 113 , the joining portion 113 B is fit with the joining portion 122 A of the outer wheel 122 of the bearing 120 described later, and thus is joined without allowing rotation relative to the outer wheel 122 via the first damping member 118 .
[0097] The first damping member 118 is a member of an approximately annular shape formed using rubber or the like. This first damping member 118 has the function of making the rotating body 113 and the outer wheel 122 of the bearing 120 integrally rotatable by its viscoelasticity, and the function of absorbing vibrations of the rotating body 113 so that they are not transmitted to the outer wheel 122 .
[0098] The bearing 120 , in the same way as the bearing 20 in the first embodiment described above, is provided with the inner wheel 121 , the outer wheel 122 , and the ball 123 disposed between the inner wheel 121 and the outer wheel 122 , and is constituted such that the inner wheel 121 and outer wheel 122 can freely rotate relative to each other with low friction by the rolling of the ball 123 .
[0099] However, the joining portion 122 A of the outer wheel 122 , to which the rotating body 113 is joined, is at the outer circumference side of the outer wheel 122 , and the joining portion 113 B of the rotating body 113 is fit to the outer circumference.
[0100] Further, at the outer circumference of the outer wheel 122 , the output projection 110 P protrudes. The output projection 110 P engages with, for example, a fork shaped engaging member provided at a member to be driven, and has the function of rotationally driving a member to be driven via the engaging portion.
[0101] Namely, the outer wheel 122 has the function of supporting the rotating body 113 , and the function of outputting to the outside the rotational driving force of the rotating body 113 .
[0102] At the bearing 120 , the inner wheel 121 is fit to the support ring 111 without allowing relative rotation, and one end face (at the Z axis plus side) is provided so as to abut the flange 111 A of the support ring 111 .
[0103] At the joining portion 122 A of the outer wheel 122 of the bearing 120 , the joining portion 113 B of the rotating body 113 is fit, and is joined via the first damping member 118 . In this way, the bearing 120 supports the rotating body 113 so as to be freely rotatable.
[0104] The inner rolling face 121 A of the inner wheel 121 of the bearing 120 has a radial inner face portion 121 Ar and a thrust inner face portion 121 As, and the outer rolling face 122 B of the outer wheel 122 has a radial outer face portion 122 Br and a thrust outer face portion 122 Bs. In this way, the bearing 120 is able to receive either of the thrust force Fs or the radial force Fr.
[0105] Further, the inner wheel 121 and the outer wheel 122 of the bearing 120 are respectively formed by injection molding or the like by a plastic material. As the plastic material, for example, polyacetal, polyether ether ketone, polybutylene terephthalate, polycarbonate and the like can be used.
[0106] On the other hand, the ball 123 is formed of a material such as a stainless alloy steel or a ceramic or the like.
[0107] The pressing portion 115 is a part which generates a pressing force to press-contact the vibrating element 112 and the rotating body 113 , and is provided with the pressure plate 115 A and a plurality of (two in the present embodiment) plate springs 115 B. The pressure plate 115 A receives the elastic return force generated by the plate springs 115 B, and is a plate having an approximately annular shape.
[0108] Between the pressing portion 115 and the vibrating element 112 , the second damping member 119 is provided.
[0109] The second damping member 119 is formed of a non-woven fabric or felt or the like. This second damping member 119 is a member which prevents transmission of the vibrations of the vibrating element 112 to the pressing portion 115 side, and is provided between the piezoelectric body 112 B and the pressing plate 115 A.
[0110] The fixing ring 116 has a disc-shaped major diameter, and is provided at the end portion of the support ring 111 . The fixing ring 116 is a member which receives the counter force of the pressing force by the pressing portion 115 which makes the vibrating element 112 press-contact the rotating body 113 . Further, the fixing ring 116 has the function of coupling the ultrasonic motor 11 with the rotation of an external operating means (for example, a focus operation ring, zoom operation ring or the like), not shown in the drawings.
[0111] At the rear face side (the z axis minus side) of the fixing ring 116 , the electric power supply portion 130 is formed.
[0112] The electric power supply portion 130 is connected to the piezoelectric body 112 B of the vibrating element 112 via the flexible printed circuit board 131 , and provides driving electric power to the piezoelectric body 112 B via the flexible printed circuit board 131 .
[0113] In the ultrasonic motor 110 constituted as above, the vibrating element 112 is pressure energized towards the rotating body 113 by the pressing force of the pressing portion 115 , and the driving face 112 Ad is press-contacted with a predetermined force with the contact face 113 A. Then, when two alternating current driving waveforms having different phases are applied to the two electrodes of the piezoelectric body 112 B of the vibrating element 112 , a progressing wave is generated at the rotating body 113 side of the elastic body 112 A by the deformation of the piezoelectric body 112 B. The rotating body 113 (contact face 113 A) which press-contacts the vibrating element 112 (driving face 112 Ad) is friction driven by this progressing wave and rotates. The rotation of the rotating body 113 is transmitted to the outer wheel 122 of the bearing 120 via the first damping member 118 , and the outer wheel 122 , namely the output projection 110 P rotates (revolves) and outputs the rotation power to the outside.
[0114] The bearing 120 is able to stably and rotatably support the rotating body 113 while resisting the thrust force Fs by the pressing portion 115 applied to the outer wheel 122 via the rotating body 113 . Further, it is able to allow the outer wheel 122 to stably rotate, preventing eccentricity, while resisting the radial force Fr arising when the output projection 110 P drives the member to be driven. As a result, it is possible to output to the outside the rotational force with little fluctuation in speed, via the outer wheel (output projection 110 P).
[0115] Further, in the same way as for the above described first embodiment, the inner wheel 121 and the outer wheel 122 of the bearing 120 are formed of a plastic material. Because of this, the constitution can be light, and further, it is possible to integrally mold the output projection 110 P protruding at the outer circumference as described above, and it can be manufactured at low cost.
Third Embodiment
[0116] Below, the third embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a longitudinal (axial direction) cross section drawing of the ultrasonic motor 210 of the third embodiment.
[0117] The third embodiment is approximately the same as the second embodiment, but differs in the point that the balls 123 are held by the retainer 125 . The other parts are the same as for the second embodiment, and thus are assigned the same reference numbers, and explanations thereof are omitted.
[0118] The retainer 125 is an annular member extending along the entire circumference of the gap between the inner wheel 121 and the outer wheel 122 . Further, as shown in FIG. 5 , in the retainer 125 , a cross section parallel to the central axis of the retainer 125 is inclined by a prescribed angle with respect to this central axis. Namely, the retainer 125 has a shape wherein a part of the side face of a cone has been cut out to a predetermined width. The side face of the retainer 125 is provided with a plurality of holes, and the balls 123 are rotatably held in these holes.
[0119] The retainer 125 is made of plastic, and is formed by injection molding or the like. As the plastic material, for example, polyacetal, polyether ether ketone, polybutylene terephthalate, polycarbonate and the like can be used.
[0120] According to the present embodiment, the balls 123 are held by the retainer 125 , thus the spacing of the balls 123 is held constant, and it is possible to prevent the balls from contacting each other. In this way, because the balls do not contact each other, there is no generation of contact sounds arising from the balls rubbing with or colliding against each other. Accordingly, it is possible to achieve further silencing of the ultrasonic motor 210 when operating.
[0121] Further, because the retainer 125 can be manufactured of plastic, its manufacturing cost can be made low. In addition, the number of the balls 123 can be reduced and the assembling operation becomes simple and easy.
[0122] The above embodiments have the following effects.
[0123] (1) In the ultrasonic motor 10 , 110 , or 210 , the outer wheel 22 or 122 is made of a substance having plasticity such as a plastic material or the like, and has a lower hardness and higher flexibility than the balls 23 or 123 which are constituted of a metal material or the like. Because of this, when the ultrasonic motor 10 , 110 , or 210 is driven, the outer wheel 22 or 122 and the balls 23 or 123 contact stably and flexibly, and thus the driving of the ultrasonic motor 10 , 110 or 210 can be designed to be stable and quiet.
[0124] (2) In the ultrasonic motor 10 , 110 , or 210 , for the bearing 20 or 120 rotatably supporting the rotating body 13 or 113 , the inner rolling face 21 A or 121 A of the inner wheel 21 or 121 has the radial inner face portion 21 Ar or 121 Ar, and the outer rolling face 22 B or 122 B of the outer wheel 22 or 122 has the radial outer face portion 22 Br or 122 Br, and because of this, the outer wheel 22 or 122 can be rotated stably while preventing eccentricities, while resisting the radial force Fr. Further, the outer wheel 22 is formed of a plastic material. Because of this, the degree of freedom in shaping is high, and complex shapes can be also integrally molded, and can be manufactured at low cost.
[0125] (3) At the outer circumference of the outer wheel 22 or 122 of the bearing 20 or 120 , the output gear 10 G or output projection 110 P which outputs rotational power to the outside is provided. Because of this, there is no need to provide a separate member for output, and the constitution can have a low cost by reducing the number of parts and the number of assembly steps.
[0126] (4) In the bearing 20 or 120 which rotatably supports the rotating body 13 or 113 , the inner rolling face 21 A or 121 A of the inner wheel 21 or 121 has the thrust inner face portion 21 As or 121 As, and the outer rolling face 22 B or 122 B of the outer wheel 22 has the thrust outer face portion 22 Bs or 122 Bs, and because of this, the outer wheel 22 or 122 can be supported to be stably rotatable while resisting the thrust force Fs by the pressing spring 15 or pressing portion 115 operating on the outer wheel 22 or 122 via the rotating body 113 .
[0127] (5) By disposing the damping member 18 or 118 between the outer wheel 22 or 122 of the bearing 20 or 120 , and the rotating body 13 or 113 , the vibrations of the rotating body 13 or 113 are absorbed and is it possible to suppress their transmission to the outer wheel 22 .
[0128] (6) The inner wheel 21 or 121 of the bearing 20 or 120 is formed of a plastic material. Because of this, the degree of freedom in shaping is high, and complex shapes can also be integrally molded, and can be manufactured at low cost.
[0129] (7) The camera 1 carries out focus point adjustment by moving the cam tube 5 by the driving of the ultrasonic motor 10 or 110 . By this means, smooth focus point adjustment is possible.
[0130] (8) Furthermore, in the case of the constitution wherein the balls 123 are held by the retainer 125 , there is no generation of contact noise arising from the balls 123 rubbing against or colliding with each other, and it is possible to achieve further silencing of the ultrasonic motor 210 . Further, by manufacturing the retainer 125 of plastic, the manufacturing costs can be reduced.
(Modifications)
[0131] The present invention is not limited to the above explained embodiments, and many modifications and variations such as those shown below are possible, and these are also within the scope of the present invention.
[0132] (1) In the embodiments, explanations were given showing as an example an ultrasonic motor 10 or 110 where the rotating body 13 or 113 rotates as an vibration actuator. However, as the form of the vibration actuator, this is not a limitation, and it may be an ultrasonic motor having a form wherein the support shaft rotates, or an ultrasonic motor of a linear type.
[0133] (2) In the embodiments, explanations were given showing as an example an ultrasonic motor 10 or 110 as a vibration actuator, but without being limited to this, for example, it may also be a vibration actuator using vibrations outside of the ultrasonic region.
[0134] (3) In the embodiments, an example is shown where the ultrasonic motor 10 or 110 is used as a driving source for the focus point adjustment of the lens barrel 3 , but without being limited to this, for example, it may also be a driving source of a zooming operation of a lens barrel 3 , or a driving source of a hand shake correction mechanism which corrects hand shake by driving a part of the imaging system of the camera. Furthermore, it may also be applied to a video camera, a mobile phone, or the like.
[0135] (4) In the third embodiment, an explanation was given for an example wherein the balls 123 of the second embodiment are held by the retainer 125 , but without being limited to this, for example, the balls 23 in the first embodiment may also be held by a retainer.
[0136] Further, the embodiments and modifications may be used in appropriate combinations, but detailed explanations are omitted. Further, the present invention is not limited by the embodiments explained above. | A vibration actuator comprising: a vibration portion which contacts a relative movement portion, and produces necessary vibration for a relative movement of the relative movement portion; a first member provided to hold the relative movement portion between the first member and the vibration portion, and moves relative to the vibration portion in response to movement of the relative movement portion with respect to the vibration portion; a second member which faces the first member via a rolling member, and supports the first member so that the first member is movable relative to the vibration portion; and a pressing member which generate a pressing force between the second member and the vibration portion so that the vibration portion and the relative movement portion are in contact with each othercome in contact with each other; and wherein the first member comprises a plastic substance. | 8 |
FIELD OF THE INVENTION
This invention is aimed at providing a stiff wire rack, sometimes referred to as a laundry tub caddy, for household use which is located in and hangs onto the sides of a tub such as a laundry tub or a sink and is adjustable in width to accommodate different size sinks or tubs.
BACKGROUND OF THE INVENTION
Stiff wire racks are used in industry and in the home for a variety of purposes. Typically, in the home the rack may be used in a kitchen sink for holding dishes to dry after they have been washed. Other uses in the home may be in a laundry tub for holding cleaning supplies used for doing the laundry or for holding articles to dry after they have been washed. Typically, as an example, a wire rack in the laundry tub might be used for holding paint brushes for drying after they have been washed and/or the paint can and cleaning materials.
In the above-described uses and in other cases for domestic or household use, the wire racks which are commercially available for sitting into a tub or sink are of single size so are not adaptable for use in different size tubs or sinks. Therefore, the homeowner may need a number of different wire racks for use in a sink or a laundry tub when the tubs are of different dimensions. Also, this means that the vendors of the stiff wire racks have to carry a number of different size units to accommodate purchasers for the different size tubs and sinks that are in the purchasers' homes.
SUMMARY OF THE INVENTION
A stiff wire rack is made of two identical support members, one generally overlaying the other. Clips hold corresponding wires of each of the support members together while permitting them to be slidably moved with respect to one another. In this fashion the wire rack can be adjusted in size to accommodate different sized laundry tubs or sinks. At one end of each of the two sections are upstanding hanger members which are hingedly or pivotally attached at one end to the support members and are hooked at their other ends to engage the upper edge of the tub or sink to hold the rack in place within the confines of the tub.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial break-away perspective view of an embodiment of the invention;
FIG. 2 is a view illustrating the invention in place in a tub or sink;
FIG. 3 is an underside view of the support members;
FIG. 4 is a perspective view of a support member; and
FIG. 5 is a sectioned view of a clip for holding the support members together.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A wire rack or laundry tub caddy 10 rests inside a laundry tub or kitchen sink 11 and has a pair of horizontal stiff wire bottom support bases 12 for holding cleaning supplies or the like and upwardly extending left and right side hanger members 13 which have hooks 14 at their upper ends to engage the top edge 17 of a tub or sink 11 to hold the rack in place.
The bottom supports 12 are virtually identical sections and are constructed in a conventional fashion out of crossed stiff wires 15 . Preferably wires 15 are coated with some type of plastic for appearance and for protection against wear or rust. The two sections 12 A and 12 B rest one over the other with the respective wires 15 in contact with one another. A set of clips 16 generally in a C shape are spaced along the wires 15 to engage and hold together respectively corresponding wires of the two sections 12 A and 12 B so that they are held together but at the same time allowing them to be slidably moved left or right or sideways with respect to one another, as illustrated in the drawings. In this fashion, then, the bottom supports 12 can be adjusted as required to fit into tubs or sinks of various sizes.
The upward extending hanger members 13 are curled at 19 for pivotal attachment at their lower ends to respective ends of the bottom support members 12 . Preferably the lower ends of members 13 are curved upward to engage crosswires 15 at the ends of the horizontal support members 12 to provide the pivotable engagement At their upper ends hanger members 13 have hooks 14 for grasping the top edges 17 of sink or tub 11 to hold the rack in place within the confines of the sink or tub.
The front and back sides of the horizontal support or base member 12 may have upstanding walls 18 made out of stiff wire to keep anything resting on the base members from falling off the front or back edges. | A stiff wire rack for hanging in a laundry tub or sink is adjustable to accommodate tubs or sinks of various sizes. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the invention
This invention relates to a product having corrosion inhibiting properties consisting essentially of the reaction product of a triflouroethanol with a monocyclohexylamine, hereinafter referred to as "a cyclohexylamine," or a mixture of a cyclohexylamine and a dicyclohexylamine; a composition having corrosion inhibiting properties consisting essentially of a liquid carrier and disposed therein the reaction product of a triflouroethanol with a cyclohexylamine or with a mixture of a cyclohexylamine and a dicylohexylamine; a combination of a solid body carrying thereon a product having corrosion inhibiting properties consisting essentially of the reaction product of a triflouroethanol with a cyclohexylamine or with a mixture of a cyclohexylamine and a dicyclohexylamine; and a process for inhibiting corrosion of a metal surface by contacting the same with the reaction product of a triflouroethanol with a cyclohexylamine or with a mixture of a cyclohexylamine and a dicyclohexylamine.
2. Description of the Prior Art
The susceptibility of a metal surface to corrosion in the presence of water or in an atmosphere containing acidic components is well known. Thus the surfaces of metallic components in a closed system are susceptible to corrosion upon standing over a long period of time. For example, in an automobile engine, when not in use over a long period of time, as when the same is being transported, the inner surfaces thereof can be corroded because of the condensation of water or water vapor thereon or, if the engine has been previously operated, because of the acidic corrosion materials produced therein. It is common in shipping or storing items having metallic parts, such as heat exchangers, pipes, hydraulic cylinders, automotive parts, gasoline and diesel engines and the like, to coat the same with a mineral oil and then to wrap the coated item to form a closed container to reduce corrosion. However, coatings can flow from the verticle surfaces of such metal members so treated, as a function of time, temperature and gravity, to expose such surfaces to corrosion as a result of water and moisture formation on such surfaces, and acidic atmospheres contained therein.
In U.S. Pat. Nos. 3,558,513 and 3,663,618 to Maurice S. Baseman reaction products of hexaflouroisopropanol with cyclohexylamine, dicyclohexylamine or mixtures of the two have shown to posses corrosion inhibiting properties. However, the reaction products in these patents are crystalline materials. They are shown therein to be soluble in many carriers, for example, petroleum oil, tricresyl phosphates, mineral oil and water. Unfortunately, when these reaction products from such carriers are used, they will sublime from the surface of the carrier and recrystallize on any adjacent metal surface and form irregular coatings thereon, resulting in reduced corrosion protection thereon, or for example in a gasoline or diesel engine such recrystallization will result in clogging holes and and openings, such as fuel injector ports, resulting in unsatisfactory operation in such engines.
I have found in the present invention that the susceptibility of metal surfaces, in an open or closed system, to corrosion in the presence of condensed water or in an atmosphere containing acicic components, for example, from the combustion of a fuel, such as gasoline or a diesel fuel, can be inhibited or substantially reduced by the mere expedient of contacting such metal surface with the reaction product of a triflouroethanol with (1) a cyclohexylamine or (2) a mixture of a cyclohexylamine and a dicyclohexylamine.
SUMMARY OF THE INVENTION
I have found that the novel reaction product of a triflouroethanol with a cyclohexylamine or with a mixture of cyclohexylamine and a dicyclohexylamine posses corrosion inhibiting properties. These reaction products can be prepared simply by mixing a triflouroethanol with a cyclohexylamine or with a mixture of a cyclohexylamine and a dicyclohexylamine at ambient temperatures and pressures, for example, 72° F. and 14.7 pounds per square inch gage. The reaction proceeds rapidly, within about two to three minutes, with evolution of heat, and within a short time, for example, fifteen to twenty minutes, the reaction product returns to ambient temperature. The reaction product remains a liquid during the reaction period and after completion of the reaction. In use the product will volatalize at ambient conditions to form a corrosion inhibiting continous film on any metal body enclosed with the product in the vicinity thereof.
When the triflouroethanol is reacted with the cyclohexylamine to produce the novel reaction product, the triflouroethanol can be in the range of about 25 to about 75 parts by weight and the cyclohexylamine can range from about 75 to 25 parts by weight. Preferably they are admixed in the range of about 50 parts by weight each, that is in about stoichiometric amounts.
I have found that the product of a triflouroethanol with a dicyclohexylamine alone, though novel, will not function as a corrosion inhibitor in contact with a metal surface under test conditions as noted herein. However, I have also found, as stated above, that the novel reaction product of a triflouroethanol with a mixture of a cyclohexylamine and a dicyclohexylamine will function as a corrosion inhibitor in contact with a metal surface. When a triflouroethanol is reacted with a mixture of a cyclohexylamine and a dicyclohexylamine to form a reaction product that will function as a corrosion inhibitor, the triflouroethanol can be in the range of about 25 to about 75 parts by weight and the combined cyclohexylamine and dicyclohexylamine can range from about 75 to about 25 parts by weight, and preferably about 50 parts by weight of triflouroethanol and 50 parts by weight of the mixture of the cyclohexylamine and the dicyclohexylamine, with the latter mixture being composed of about 25 to about 85 weight percent of the cyclohexylamine and about 15 to about 75 weight percent of the dicyclohexylamine, and about preferably 50 to about 75 weight percent of the cyclohexylamine and about 50 to 25 weight percent of the dicyclohexylamine. As an example, using 2,2,2-triflouroethanol as the triflouroethanol and cyclohexylamine or dicyclohexylamine as the reactant therewith, I believe the novel products produced herein are cyclohexylammonium 2,2,2-triflouroethoxide, [CF 3 CH 2 O - ] [(C 6 H 11 )NH 3 + ] and dicyclohexylammonium 2,2,2-triflouroethoxide [CF 3 CH 2 O - ] [(C 6 H 11 ) 2 NH.sub. 2 + ], respectively.
It is within the purview of my invention that one or more triflouroethanols, such as 2,2,2-triflouroethanol; 2,2,1-triflouroethanol; and 2,1,1-triflouroethanol can be reacted with cyclohexylamine or the mixture of cyclohexylamine and dicyclohexylamine to prepare the novel product therein. In a prefered embodiment, I use 2,2,2-triflouroethanol. Similarly, it is within the purview of my invention that not only the unsubstituted mono and the dicyclohexylamine can be reacted with the above triflouroethanols to obtain the novel products herein, but also cyclohexylamines and dicyclohexylamines wherein the hydrogens on the ring can be replaced with one or more normal or branched alkyls having from 1 to 6 carbon atoms, preferably methyl, cyclic alkyls and phenyl. Specific examples of cyclohexylamines that can be used include cyclohexylamine (CHA), methyl (CHA), isopropyl (CHA), phenyl (CHA), 1,3-dimethyl (CHA); examples of dicyclohexylamines that can be used include cyclohexylamine (DCHA), 2-methyl (DCHA), 3-isopropyl (DCHA), 1-phenyl (DCHA), 2,2-dimethyl (DCHA), 10-isobutyl (DCHA), 1,10-diethyl (DCHA), 2-hexyl (DCHA), 12-isopropyl (DCHA), 1-methyl, 8-ethyl (DCHA), 3-pentyl, 11 ethyl (DCHA), 4-methyl, 5-cyclohexyl (DCHA), 1,3,7-trimethyl (DCHA), 1,2,3,8,10,11-hexamethyl (DCHA), etc.
The novel reaction products defined above can be used as corrosion inhibitors, since they are liquids; they can also vaporize to form continuous films on metal surfaces to protect the same.
In one embodiment the novel reaction products defined above can be applied to any solid body, either as a coating thereon or as an impregnant, and said solid body can serve as a carrier thereof. Such solid bodies can include paper, cloth, felt of cotton, wool, rayon or nylon, plastics such as polyethylene, polyurethane, polyvinyl acetate, polyvinal chloride and the like. Such solid bodies carrying the novel reaction products can therefore serve as a base from which the novel reaction products can volatilize therefrom to form vapors that can condense on a adjacent metal surface to function as a corrosion inhibitor. Additionally, some of these solid bodies carrying the novel reaction products, for example, a fiberous material, such as paper or cloth, can be used as a wrapping or a cover for ferrous metals to be stored or transported to prevent rusting thereof.
In a preferred embodiment, the novel reaction products can be disolved in many suitable liquid carriers, including water, but particularly in an oleaginous vehicle, preferably a relatively non-volatile fluid having a viscosity between about 60 to 1,000 saybolt universal seconds (SUS), and preferably between about 60 to about 800 (SUS) at 25° C. Suitable vehicles include petroleum hydrocarbon oils, such as paraffinic and naphthenic oils; kerosene and gasoline; greases; hydraulic fluids; vegetable oils, such as castor oil and soybean oil; synthetic oils, such as long chain esters of dibasic acids, for example bis(2-ethylhexyl) sebacates, and the like, and neopentyl polyols, known as Mobil Jet Oil II, and sold by Mobil Oil Corp., defined in military specifications as MIL-L-23699. The amount of the novel reaction product carried by the liquid carriers can vary over a wide range, for example from about 0.1 weight percent to more than 10 weight percent, preferably from about 0.2 weight percent to about 3 weight percent, based on the weight of the carrier.
The novel composition defined above, including the liquid carrier, particularly when the liquid carrier is an oleagenois vehicle, is especially effective when the same is used in a closed system or container, such as defined above, to protect the metal surfaces in such a system from corrosion. In such case, the novel reaction product will tend to volatilize until the free space in the closed system or container is saturated therewith. The vapors will then coat the metal surface, or if the metal surface is wet with water, will displace or permeate the same, thereby to provide a corrosion inhibiting coating thereon. Since the free space is confined, the novel reaction product cannot easily escape therefrom and therefore will be available for extremely long periods of time, for example, up to a year and even more, to exert its anticorrosion properties on the metal surface. The closed system can be any system, relatively permanent, as in an internal combustion engine, or semipermanent, as in a package used in shipping metal parts.
The metal surfaces protected by the novel reaction products herein include steel, cast iron, copper, brass, and aluminum.
The novel reaction products or novel compositions carrying the same can include other carrier liquids such as synthetic polyesters, for example, diethylene glycoladipate, monohydric alcohols, such as ethyl or propyl alcohol, and glycols, admixed in any and all proportions with each other, silicone oils, such as dimethyl polysiloxanes, and flourocarbon liquids. These additional carrier fluids can be used with at least about 0.1 weight percent and as high as about 10 weight percent of the novel reaction product. Additionally, nitrites, nitrates, phosphates, and chromates as inhibitors can be present.
DESCRIPTION OF PREFERRED EMBODIMENTS
The following will further illustrate the invention defined and claimed herein.
EXAMPLE NO. 1
Ten grams of 2,2,2-triflouroethanol were admixed with 10 grams of cyclohexylamine at 72° F. and at atmospheric pressure in a glass test tube having a height of 125 millimeters and a diameter of 25 millimeters. An exothermic reaction resulted raising the temperature from 72° F. to 127° F. over a period of about 2 minutes. After about 15 minutes the temperature of the resulting reaction product returned to 72° F. The reaction product was a water white clear liquid having a boiling point of 250° F. (Cottrell Boiling Point Apparatus), a flash point of 145° F. to 150° F. (Cleveland Open Cup), and the pour point was approximately 6° F. (ASTM D97).
EXAMPLE NO. 2
Ten grams of 2,2,2-trifluorethanol were admixed with a mixture composed of 7.5 grams of cyclohexylamine and 2.5 grams of dicyclohexylamine at 72° F. and atmospheric pressure in a test tube similar to that used in Example No. 1. An exothermic reaction resulted, raising the temperature from 72° F. to 113° F. over a period of about 2 minutes. After about 15 minutes the temperature of the resulting reaction product returned to 72° F. The reaction product was a water white clear liquid having a boiling point of approximately 215° F. (Cottrell Boiling Point Apparatus), a flash point of 140° F. to 145° F. (Cleveland Open Cup), and the pour point was approximately 45° F. (ASTM D97).
EXAMPLE NO. 3
The procedure of Example No. 2 was repeated except that the reactants consisted of 7.8 grams of 2,2,2-trifluorethanol and 12.8 grams of dicyclohexylamine. An exothermic reaction resulted, raising the temperature from 72° F. to 131° F. over a period of about 2 minutes and resulting in the formation of a solid body of crystalline material. After about 20 minutes the temperature of the reaction product returned to 72° F., with the crystalline material still being present. The boiling point of the reaction product was approximately 250° F. (Cottrell Boiling Point Apparatus), the flash point was 180° F. (Cleveland Open Cup), and the melting point was 117° F. (capillary tube).
The vapor phase testing in the following Examples No. 4 to Example No. 6 was carried out using apparatus proposed by ASTM Task Group C-II (Vapor Phase Test Apparatus available from Koehler Instrument Co., Inc., Bohemia, N.Y.; composed of the following: 1018 steel coupons 1 inch long and 0.5 inch diameter; a teflon sleeve 21/2 inches long having an internal diameter of 3/4 inch, a tapered neck 250 milliliter glass flask; and a specimen cup for holding the test oil 2 and 3/4 inches long and 1 inch in diameter with 11 holes each 1 millimeter in diameter, spaced equidistant from each other in the wall of the cup, 1 and 1/8 inch from the bottom of the cup, to admit water vapors therein. A stainless steel specimen holder approximately 4 inches long and 3/8 inches in diameter, and threaded on one end to screw in the test coupon and having on the other end an inlet and an outlet port, which can be attached to tubes for the introduction of circulating water), was used. The steel specimen holder was inserted into the teflon sleeve, the steel coupon was screwed into one end of the stainless steel holder, with a teflon washer applied thereon to prevent slipping of the coupon through the teflon sleeve, and the oil specimen cup was slipped over the teflon sleeve and held tight by an "O" ring, so that the test coupon did not touch the test oil. This apparatus was then placed in the flask where the teflon sleeve formed an air-tight seal with the tapered neck of the flask. Hoses were attached to the inlet and outlet ports on the other end of the stainless steel holder and cooling water was circulated therein. The flask was then lowered into a heated water bath and held in place with clamps.
EXAMPLE NO. 4
A reaction product was prepared using 50 parts by weight of cyclohexylamine and 50 parts by weight of 2,2,2-trifluorethanol following the procedure of Example No. 1. A mixture was prepared using the above reaction product and Military Specification Oil, MIL-L-21260, Grade 30, Lubricating Oil, Internal Combustion Engine, Preservative and Break In such that the resulting mixture contained 0.3 weight percent of the reaction product. Two grams of this mixture was placed in the test cup of the proposed ASTM apparatus described above. Two grams of the neat oil, MIL-L-21260, were placed in another test cup of the proposed ASTM apparatus. The test samples were placed in a water bath and held at 130° F. for 16 hours. Cooling water, maintained at 70° F., was circulated through the steel test coupon holder. At the end of the 16 hour period, 5 milliliters of distilled water was placed in the apparatus flask. The above conditions were then maintained for another six hours. At the end of the six hour period the steel coupons were removed and examined for corrosion. The specimen over the neat oil was heavily rusted, while the specimen over the cup with the novel reaction product defined above was essentially free from rust.
EXAMPLE NO. 5
A reaction product was prepared using 50 parts by weight of 2,2,2-trifluoroethanol and 50 parts by by weight of a mixture composed of 75 weight percent cyclohexylamine and 25 weight percent dicyclohexylamine following the procedure of Example No. 2. A mixture was prepared using the above reaction product and Kendall 10W-30W Motor Oil, such that the resulting mixture contained 0.5 weight percent of the above reaction product. Two grams of this mixture were placed in the specimen cup of the proposed ASTM apparatus described above. Two grams of the Kendall 10W-30W Motor Oil neat were placed in another specimen cup. The flasks were held at 130° F. for 16 hours with cooling water maintained at 70° F. circulated to the steel specimen holder. At the end of this period, five milliliters of distilled water were added to the flask and the test was continued for an additional six hours. At the end of the six hour period, the steel coupons were removed and examined for signs of rusting. The steel coupon in the neat oil was found to be heavily rusted, while the coupon in the cup containing the oil and the reaction product was essentially free from rust.
EXAMPLE NO. 6
The work described in Example No. 4 was repeated, except that the reaction product was prepared using 36 parts by weight of 2,2,2-trifluoroethanol and 64 parts by weight of dicyclohexylamine. As in Example No. 4, the MIL-L-21260, Grade 30 Lubricating Oil contained 0.3 weight percent of the above reaction product. The results of this test indicated no significant difference between the use of the neat oil and the oil containing the above reaction product, for in each case the test specimens were both heavily rusted.
The results obtained in Examples No. 4, 5, and 6 are quite unusual. when the triflouroethanol was reacted with the cyclohexylamine in Example No. 4, the reaction product proved to be an excellent vapor phase corrosion inhibitor for metals, while in Example No. 6 the reaction product of the triflouroethanol with the dicyclohexylamine proved to be an ineffective corrosion inhibitor in the vapor phase. And yet when the reaction product of Example No. 5 using the triflouroethanol and both of the amines were used, excellent corrosion inhibiting properties in the vapor phase was found to be the case. This may be due to the fact as evidenced by Example No. 3, that the reaction product of triflouroethanol and the dicyclohexylamine alone is a crystalline material. When both cyclohexylamine and dicyclohexylamine are used in the reaction with triflouroethanol, apparantly the components of the reaction product relate synergestically with each other to form the clear, water-white product of Example No. 2.
EXAMPLE NO. 7
A mixture was prepared composed of 150 milliliters of distilled water and 0.3 weight percent thereof of the reaction product of Example No. 1. This mixture was placed in a jar 4 inches high and having a diameter of 3.25 inches. Another similar jar contains only 150 milliliters of distilled water. Submerged in each jar was a polished 1020 steel panel 2.5 inches high, 1.25 inches wide and 1/8 inch thick. The lid was screwed onto each jar and the edges of the jar and the lid were sealed with contact tape. The jars were then placed into an electric oven and held therein at 130° F. for 16 hours. At the end of this time the steel panels were removed and examined for rusting. The specimen submerged in the water containing the reaction product of Example No. 1 was essentially free from rusting, while the specimen in the neat water showed numerous rust spots.
Obviously many modifications and variations of the invention, as hereinabove set forth, can be made without departing from the spirit and scope thereof and therefore only such limitations should be imposed as are indicated in the appended claims. | A product having corrosion inhibiting properties consisting essentially of the reaction product of a triflouroethanol with a cyclohexylamine or with a mixture of cyclohexylamine and a dicyclohexylamine; a composition having corrosion inhibiting properties consisting essentially of a carrier liquid and disposed therein the reaction product of a triflouroethanol with a cyclohexylamine or with a mixture of a cyclohexylamine and a dicyclohexylamine; a combination of a solid body carrying thereon a product having corrosion inhibiting properties consisting essentially of the reaction product of a triflouroethanol with a cyclohexylamine or with a mixture of a cyclohexylamine and a dicyclohexylamine; and a process for inhibiting corrosion of metal surface by contacting the same with the reaction product of a triflouroethanol with a cyclohexylamine or with a mixture of a cyclohexylamine and a dicyclohexylamine. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
BACKGROUND OF THE INVENTION
[0003] This invention relates to pour spouts for containers of fluid, and more particularly to pour spouts which permit transfers of fluid (liquid) based on the influence of gravity at multiple flow rates, and without the risk of spills or overflow.
[0004] It is desirable to avoid overfilling of fuel to internal combustion engines in lawnmowers, tractors, personal water craft, chain saws and power tools, outboard motors, ATV recreational vehicles and even automobiles. Spilled fuel presents health and safety risks to people and the environment in general. As a result, many states have now passed environmental legislation which regulates pour spouts which can be used in conjunction with volatile fuels and other liquids.
[0005] The opportunity for spills have various causes. First, often times the gas tanks in the aforementioned internal combustion engines have very narrow openings which requires precise pouring and/or a facilitating pour spout or funnel to prevent spills.
[0006] Many times spills occur because the operator of the pour spout does not know when the receiving vessel is full. In these cases, overflows occur before pouring can be terminated.
[0007] Yet another cause of spills is the ineffective venting of the container from which the fluid is being transferred. The result of ineffective venting is an uneven fluid flow, and even in some cases surging of the fluid. Surges can cause splashing and an uneven flow makes it extremely difficult to predict fluid levels in the receiving vessel.
[0008] Another problem encountered by gravity influenced pour spouts is airlock caused by improper venting. Airlock occurs as a result of improper venting in combination with specific volume and viscosity parameters of the fluid being transferred. Such a condition can result in fluid which will not pour even when the container is inverted. This problem, while annoying, can normally be resolved by turning the container right side up again. However, this only increases the opportunity for spills.
[0009] Examples of prior spill-proof pour spouts include U.S. Pat. Nos. 4,598,743, 4,834,151, 5,076,333, 5,249,611, 5,419,378, 5,704,408, and 5,762,117. These pour spouts all have the following drawbacks; they do not provide multiple flow rate options and they do not provide childproof locks. The present invention solves these and other problems.
SUMMARY OF THE INVENTION
[0010] One object of the present invention is to provide a pour spout for a container of fluid which will preclude the overflow of any receiving vessel into which the fluid is transferred.
[0011] Another object of the present invention is to provide a pour spout for a container which will eliminate spills when transferring fluid from the container to a receiving vessel.
[0012] Another object of the present invention is to provide a spill-proof pour spout that allows fluid to be transferred from a container to a receiving vessel at various flow rates.
[0013] Finally, it is an object of the present invention to provide a spill-proof pour spout with a childproof safety lock which prevents children from accidently spilling, pouring or dumping fluid from a container.
[0014] To achieve the foregoing objectives, the present invention provides, in a first embodiment, a pour spout for transferring fluid from a container to a vessel. The pour spout comprises a base having an inner sleeve extending outwardly therefrom, a conduit member located in the inner sleeve, and an outer sleeve slidingly engaging the inner sleeve. The conduit member has a fluid tube, an air tube and an end cap. The outer sleeve is in a first closed position wherein the outer sleeve contacts the end cap preventing fluid flow from the pour spout. The pour spout can only be opened by rotating the outer sleeve to a first or second indexed position. By rotating the outer sleeve relative to the inner sleeve, the outer sleeve is adapted to be slid to a first open position permitting fluid to flow at a first flow rate through the fluid tube and out of the pour spout. By further rotating the outer sleeve, the outer sleeve is adapted to be slid to a second open position permitting fluid to flow at a second flow rate through the fluid tube at a second flow rate and out of the pour spout.
[0015] In a second embodiment, there is provided a pour spout for transferring fluid from a container to a vessel. The pour spout comprises a base having an inner sleeve extending outwardly therefrom, a conduit member located in the inner sleeve and an outer sleeve slidingly engaging the inner sleeve. The conduit member has a fluid tube, a first air tube, a second air tube and an end cap. A biasing member urges the outer sleeve into an initial closed position that precludes the transfer of fluid through the pour spout. The base has a protrusion which coacts with the outer sleeve and a plurality of slots in the outer sleeve to facilitate an initial closed position, a first open position and a second open position. The outer sleeve also has a shoulder for coacting with the vessel to slide the outer sleeve relative to the inner sleeve from the closed position to either a first or a second open position.
[0016] These and other aspects and attributes of the present invention will be discussed with reference to the following drawings and accompanying specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] [0017]FIG. 1 is a cross-sectional view of a pour spout according to one embodiment of the present invention;
[0018] [0018]FIG. 2A is a first elevational view of a pour spout according to one embodiment of the present invention in a closed position;
[0019] [0019]FIG. 2B is a first elevational view of the pour spout shown in FIG. 2A in a first open position;
[0020] [0020]FIG. 2C is a first elevational view of the pour spout shown in FIGS. 2A and 2B in a second open position;
[0021] [0021]FIG. 3A is a second elevational view of the pour spout shown in the first open position of FIG. 2B;
[0022] [0022]FIG. 3B is a second elevational view of the pour spout shown in the second open position of FIG. 2C;
[0023] [0023]FIG. 4 is an elevational view of the pour spout shown in FIGS. 2 A- 2 C without the outer sleeve and bias member;
[0024] [0024]FIG. 5 is an elevational view of the base of the pour spout shown in FIGS. 1 - 4 ;
[0025] [0025]FIG. 6 is an elevational view of the outer sleeve of the pour spout shown in FIGS. 1 - 3 ;
[0026] [0026]FIG. 7 is a top plan view of the outer sleeve shown in FIG. 6;
[0027] [0027]FIG. 8 is an elevational view of the conduit member shown in FIGS. 1 - 4 ;
[0028] [0028]FIG. 9 is a cross-sectional view of the two-piece fluid and air tube taken along line a-a in FIG. 8;
[0029] [0029]FIG. 10 is an elevational view of the back channel of the two-piece fluid and air tube shown in FIG. 9;
[0030] [0030]FIG. 11 is an enlarged cross-sectional view of the back channel of the two-piece fluid and air tube taken along line b-b in FIG. 10;
[0031] [0031]FIG. 12 is an elevational view of the air tube cover of the two-piece fluid and air tube shown in shown in FIGS. 8 and 9;
[0032] [0032]FIG. 13 is an enlarged top plan view of the air tube cover shown in FIG. 12;
[0033] [0033]FIG. 14 is an elevational view of a second embodiment of the conduit member;
[0034] [0034]FIG. 15 is an elevational view of a pour spout having the conduit member shown in FIG. 14 in a first open position;
[0035] [0035]FIG. 16 is an elevational view of a pour spout having the conduit member shown in FIG. 14 in a second open position; and
[0036] [0036]FIG. 17 is an elevational view of a third embodiment of the conduit member.
DETAILED DESCRIPTION OF THE INVENTION
[0037] While this invention is susceptible of embodiment in many different forms, there is shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated.
[0038] Referring to FIGS. 1 - 13 there is shown a spill-proof pour spout 10 according to a preferred embodiment of the present invention. As shown in FIG. 1, the spill-proof pour spout 10 includes a base 20 having an inner sleeve 30 extending outwardly therefrom. A conduit member 40 is located in the inner sleeve 30 and includes a fluid tube 50 , a first and a second air tube 60 , 61 (see FIG. 9) and an end cap 70 . An outer sleeve 80 engages the inner sleeve 30 and is held in a normally closed position by a biasing member 90 , such as a spring or elastomeric member. In the normally closed position, the outer sleeve 80 is biased against the end cap 70 by the biasing member 90 , thereby preventing flow through the fluid tube 50 . The outer sleeve 80 is rotatably and slidably moveable with respect to the inner sleeve 30 to facilitate multiple positions of the pour spout 10 . In a preferred embodiment, the pour spout 10 is positionable in three indexed positions, a locked position as shown in FIG. 2A, a low flow position as shown in FIG. 2B, and a high flow position as shown in FIG. 2C. It is to be understood, however, that the pour spout 10 can be provided with numerous other positions, including additional positions for additional flow rates.
[0039] When describing the functionality of the spill-proof pour spout 10 of the present invention, it will be presumed that the pour spout 10 is attached to a fluid-filled container, such as, for example, a gasoline container, and a user of the pour spout is attempting to transfer fluid from the container to a receiving vessel having a receptacle into which the spout can be inserted.
[0040] As shown in FIGS. 2 A- 2 C, the outer sleeve 80 also includes a first slot 110 , a second slot 120 and a third slot 130 . The base 20 includes a protrusion 140 that cooperates with the slots 110 , 120 , 130 in the outer sleeve 80 to facilitate indexable positioning of the pour spout 10 . The outer sleeve 80 is rotatable with respect to the inner sleeve 30 so that the protrusion 140 can be aligned with one of the slots 110 , 120 , 130 . The first slot 110 facilitates a locked position. The outer sleeve 80 includes a detent 141 that maintains the protrusion 140 within the slot 110 in a locked position. The pour spout 10 can be unlocked when a sufficient force is applied to the outer sleeve 80 with respect to the inner sleeve 30 to allow the protrusion 140 to slide past the detent 141 . Once unlocked, the outer sleeve 80 can be rotated with respect to the inner sleeve 30 to allow alignment of the protrusion 140 with one of the slots 120 , 130 , which, in turn, allows the inner sleeve to be slid into an open position. As shown in FIGS. 3A and 3B, the outer sleeve 80 of the pour spout 10 includes a shoulder 100 having a lip 101 . The shoulder 100 of the outer sleeve 80 coacts with the receptacle of the receiving vessel to permit the outer sleeve 80 to slide relative to the inner sleeve 30 into an open position when pressure is applied to the spout 10 by the user. As shown in FIGS. 2B and 3A, a low flow open position is achieved when the outer sleeve 80 is slid such that the protrusion 140 is held against an end surface 142 of the slot 120 . In similar fashion, as shown in FIGS. 2C and 3B, a high flow position is achieved when the outer sleeve 80 is slid such that the protrusion 140 is held against an end surface 143 of the slot 130 .
[0041] It should be noted that in the locked position, the outer sleeve 80 is maintained in the normally biased closed position against the end cap 70 . In order to allow the protrusion 140 to rotate past the detent 141 , a plastic material may be utilized that allows some flexion of the detent and/or protrusion. Additionally, an elastomeric compression type seal may be utilized below the end cap 70 that will allow the outer sleeve 80 to be slidably pushed against the end cap just enough to further compress the seal and allow the protrusion to rotate past the detent 141 .
[0042] Referring now to FIGS. 4 and 5, in the preferred embodiment illustrated, the base 20 has a larger diameter than the inner sleeve 30 which extends outwardly from one end of the base 20 . This creates a step 150 that extends radially around one end of the base 20 . As shown in FIG. 1, the biasing member 90 in the preferred embodiment is a spring that is disposed around the inner sleeve 30 , with one end of the spring 90 resting on the step 150 . Referring once again to FIG. 5, at the end of the inner sleeve 30 opposite the base 20 , there is a notched portion 160 which receives the conduit member 40 as will be explained further below. The other end of the base 20 has a connector flange 25 that cooperates with a threaded collar of a container (not shown) to facilitate connection of the pour spout 10 to the container.
[0043] As shown in FIG. 6, the outer sleeve 80 is comprised of a first hollow tube portion 83 and a second hollow tube portion 84 . The first hollow tube portion 83 has a larger diameter than the second hollow tube portion 84 , thereby creating an inner annular step 85 around the outer sleeve 80 . The shoulder 100 extends from one end of the first hollow tube portion 83 of the outer sleeve 80 . The opposite end of the first hollow tube portion 83 of the outer sleeve 80 includes the slots 110 , 120 , 130 . As shown in FIG. 1 , when the outer sleeve 80 is placed over the inner sleeve 30 and biasing member 90 , the biasing member 90 is confined between, and bears against, the step 150 in the base 20 and the inner annular step 85 of the outer sleeve 80 . As mentioned above, the biasing member 90 keeps the pour spout 10 in a normally closed position with the second hollow tube portion 84 of the outer sleeve 80 forming a seal with the end cap 70 of the conduit member 40 . A top plan view of the outer sleeve 80 is shown in FIG. 7.
[0044] In the preferred embodiment shown in FIGS. 8 and 9, the conduit member 40 includes the first and the second air tubes 60 , 61 , the fluid tube 50 and the end cap 70 . In this particular embodiment, the air tubes 60 , 61 form discrete channels that are separate from the fluid tube 50 . Alternatively, a single air tube can be utilized. A tip portion 41 of the conduit member 40 is exposed when the outer sleeve 80 is slid to either the first (See FIG. 2B) or the second (See FIG. 2C) open position. Referring to FIG. 1, in the tip portion 41 of the conduit member 40 , the fluid tube 50 diffuses to form a fluid discharge opening 51 adjacent the end cap 70 . As shown in FIGS. 8 and 9, a first air vent aperture 170 is in the tip portion 41 of the conduit member 40 and communicates with the first air tube 60 . The first air vent aperture 170 is transverse to the first air tube 60 and has the same diameter as the first air tube 60 . A second air vent aperture 180 is also located in the tip portion 41 of the conduit member 40 and communicates with the second air tube 61 . The second air vent aperture 180 is transverse to the second air tube 61 and has the same diameter as the second air tube 61 .
[0045] When the outer sleeve 80 is slid to the first open position (See FIGS. 2B and 3A), the end cap 70 and the second hollow tube portion 84 of the outer sleeve 80 no longer form a seal preventing fluid from flowing through the pour spout 10 . Instead, the second air vent aperture 180 and the fluid discharge opening 51 of the conduit member 40 are exposed to the ambient atmosphere (i.e., within the vessel). Air flows from the air vent aperture 180 through the second air tube 61 allowing fluid to flow from the container through the fluid tube 50 and out the fluid discharge opening 51 as a result of a pressure differential between the atmosphere and the pressure developed in the container. This venting means also allows for an even air to fluid volume displacement resulting in an even rate of fluid flow.
[0046] When the outer sleeve 80 is slid to the second open position (See FIGS. 2C and 3B), the first and second air vent apertures 170 , 180 and the fluid discharge opening 51 are exposed to the ambient atmosphere. Air flows from air vent apertures 170 , 180 through air tubes 60 , 61 allowing fluid to flow from the container through the fluid tube 50 and out the fluid discharge opening 51 . Because the pressure differential is greater when both air vent apertures are exposed, the fluid flow rate in the second open position of the pour spout 10 is greater than the fluid flow rate in the first open position of the pour spout 10 .
[0047] In a preferred embodiment illustrated in FIGS. 10 - 13 , the conduit member 40 is constructed of two separate pieces for ease of manufacture: a fluid and air tube back channel 190 and an air tube cover 200 . Back channel 190 includes the fluid tube 50 , fluid discharge opening 51 , end cap 70 . A divider wall 191 runs from the end cap 70 to the opposite end of the back channel 190 . The divider wall 191 separates the fluid tube 50 from the air tubes 60 , 61 . However, in the preferred embodiment, a portion of the diameter of air tubes 60 , 61 are formed in the divider wall 191 . The portions of the air tubes 60 , 61 formed in the divider wall 191 are designated 60 ′, 61 ′ in FIGS. 10 - 11 . In addition, the back channel 191 has a plurality of slots 193 and recessed grooves 194 for receiving tabs 201 and catches 202 from the air tube cover 200 . The remaining portions of the air tubes 60 , 61 are formed in the air tube cover 200 and are designated 60 ″, 61 ″ in FIG. 13. The air tube cover 200 includes the air vent apertures 170 , 180 . The air vent apertures 170 , 180 are transverse to and intersect the semi-formed air tubes 60 ″, 61 ″. When assembled, the tabs 201 and catches 201 are inserted in the slots and snap fitted into the recessed grooves 194 . FIG. 9 illustrates the assembled two-piece conduit member 40 .
[0048] Another embodiment of the present invention is shown in FIGS. 14 - 16 . In this embodiment, there is only a single air tube 60 in the conduit member 40 . As a result there is also only a single air vent aperture 170 . The diameter of the air vent aperture 170 is the same as the air tube 60 . With reference specifically to FIG. 15, when the outer sleeve 80 is slid into the first open position, a first portion of the air vent aperture 170 is exposed. As shown in FIG. 16, the entire air vent aperture 170 is exposed in the second open position. Alternatively, a greater portion of the air vent aperture 170 may be exposed in the second position compared to that of the first position. In all other respects, the embodiment illustrated in FIGS. 14 - 16 is the same as the embodiment illustrated in FIGS. 1 - 13 and discussed above.
[0049] In yet another embodiment illustrated in FIG. 17, there is a single air tube 60 in the conduit member 40 . However, rather than having a single air vent aperture 170 , there are first and second air vent apertures 170 , 180 which communicate with the single air tube 60 . The first and second air vent apertures 170 , 180 are transverse to, and have the same diameter as, the air tube 60 . In the first open position, only the first air vent aperture 170 is exposed. In the second open position, the first and second air vent apertures 170 , 180 are exposed. Alternatively, in each of the positions, only a portion of the air vent apertures 170 , 180 are exposed. In all other respects, the embodiment illustrated in FIGS. 14 - 16 is the same as the embodiment illustrated in FIGS. 1 - 13 and discussed above.
[0050] It should be noted that for all of the embodiments described, when an air vent aperture is exposed in a particular indexed position of the outer sleeve 80 , it may be partially covered by the outer sleeve 80 . The resulting partial exposure of an air vent aperture regulates the intake of air through the associated air tube(s), thereby governing the flow rate. By changing the amount in which the air vent aperture is exposed, pour spout designs having various multiple flow rate positions can be achieved. Thus, for certain flow rates, a given air vent aperture may not be fully exposed to the ambient atmosphere.
[0051] It should also be noted that the indexed positioning of the outer sleeve can be achieved through means other than a slot and protrusion combination. For example, a series of detents can be provided on either the outer surface of the inner sleeve or the inner surface of the outer sleeve that coact with a corresponding protrusion on an opposing surface. Such an arrangement would be within the skill of one of ordinary skill in the mechanical arts.
[0052] From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims. | A spill-proof pour spout for transferring fluid from a container to a vessel comprising a base having an inner sleeve extending outwardly therefrom, a conduit member located in the inner sleeve, and an outer sleeve slidingly engaging the inner sleeve. The conduit member has a fluid tube, and air tube and an end cap. The outer sleeve is in a first closed position wherein the outer sleeve contacts the end cap preventing fluid flow from the pour spout. The pour spout can only be opened by rotating the outer sleeve to a first or second indexing position. By rotating the outer sleeve either clockwise or counterclockwise relative to the inner sleeve, the outer sleeve is adapted to be slid to a first open position permitting fluid to flow at a first flow rate through the fluid tube and out of the pour spout. By further rotating the outer sleeve either clockwise or counterclockwise, the outer sleeve is adapted to be slid to a second open position permitting fluid to flow at a second flow rate through the fluid tube at a second flow rate and out of the pour spout. | 1 |
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates in general to forming an impression of a foot for the modeling of footwear and foot appliances. More specifically, the present invention relates to forming a foot impression of a foot in a dynamic state that simulates the gait cycle that occurs in human ambulation.
2 Prior Art
It is desirable to form an impression of the human foot for making molds for footwear and foot-related appliances. It is a difficult task because of the foot's mobility and variety of tissue densities. A testament of this difficulty is the percentage of the population that are ironically intolerant of their footwear and appliances.
In order to provide background information so that the invention may be completely understood and appreciated in its proper context, reference is made to a number of prior art practices and patents as follows:
A common trade practice as taught by Langer Biomechanics Group of 12 E Industry Ct., Deer Park, N.Y. 11729, and others, molds the foot in plaster gauze and a technician holds the foot suspended in a position while the plaster cures. The method does not perform as the present invention because of the potential for inconsistencies in determining a position to hold the foot. Also, there is no weightbearing on the foot, which inherently would change the foot's shape compared to the suspended, non-weightbearing state.
Another common trade practice as marketed by Hersco Arch Products, 138 E 26th St., NYC, N.Y. 10010, and others, is to press the foot in a crystalline foam block that crushes and compresses to the pressures of the foot. The foot can be pressed into the block in a variety of manners, including one simulating the gait cycle; however, the method does not perform as the present invention because the crystalline foam gives way under very slight pressure; therefore, there is no support or resistance. If the foot is held and pressed lightly into the foam, the mold is essentially the same as the Langer suspended method. It likewise shares the faults of the Langer method. If the foot is not held and is allowed to press into the block with full weightbearing, the lack of resistance and support in the crystalline foam will allow the foot to spread into a flattened or incorrect position against the flat surface on which the block is resting.
Denis, U.S. Pat. No. 4,603,024 discloses molding of the foot in a block of modeling clay. The method does not perform as the present invention for the same reasons as Hersco and Langer. Although clay molds differently than crystalline foam, by viscously displacing as opposed to crushing, clay that is in a consistency to mold the foot will show the same faults in molding.
Another common trade practice, as marketed by Peterson Laboratories, One Mill St., Parish, N.Y. 13131, and others, makes an impression of the foot in a thin thermoplastic sheet while standing or being pressed on a foam cushion. The method does not perform as the present invention because compressed foam rubber cells are connected to adjoining cells and distort these adjoining cells, even if there is no direct pressure on the adjoining cells. This distortion creates uneven pressures on the surface of the foot and puts inaccurate contours into the mold. In addition to the inaccurate contours, inconsistencies will result with varied bodyweights on the same cushion.
Another common trade practice as marketed by Superfeet, 1852 Peace Portal Dr., Blaine, Wash. 98239 and N.W. Podiatric Laboratory, 1091 Fir Ave., Blaine, Wash. 98230, makes a mold or impression of the foot in thermoplastic or thermocork sheets or plaster gauze by applying the mold medium to the foot by vacuum-bag suction. The vacuum-bagged foot is then placed in a shoe or against a flat surface and held in a position until the mold medium cures. The method does not perform as the present invention, for the same reasons stated in the Langer case. Also, pressing the foot against a flat surface or shoe distorts the natural contour of the foot.
Another common trade practice as marketed by Riecken Orthotic Lab, 401 N. Green River Rd., Evansville, Ind. 47715, makes a mold of the foot in thermowax sheet by pressing, wiggling and digging the foot and accompanying mold medium into a box of sand. The method does not perform as the present invention, because the motions of the foot that force it into the sand are not normal ambulatory foot motions and create an unnatural and inaccurate contour.
Arefit of 1931 Las Plumas Ave., San Jose, Calif. 95133, computer images an impression of the foot by placing it on a bed of digitally read plunger rods that extend out of a flat surface. This method does not perform as the present invention for the same reasons as stated above for Hersco and Superfeet/N.W. Podiatric. Also, the foot contour is affected by the flat surface.
Foot Image Technology of 1620 SW Overturf, Bend, Oreg. 97702, computer images the foot with an optical image scanner while the foot is placed on a flat glass plate. This method does not perform as the present invention because the foot contour is affected by the flat glass plate. Also, for an image to be converted into a three-dimensional model, or mold, a designer/programmer must interpret the data from the image and convert this into tool paths. This interpretation is subject to error.
Tekscan of 451 D St., Boston, Mass. 02210, computer images the foot with a bed of force sensors placed on a flat surface and read by a computer. The foot may be applied to the bed in any manner, including gaited; however, the method does not perform as the present invention. The bed senses force-variance over the foot's surface, so three-dimensional surfaces are possible to image; however, as in the Foot Image Technology case, a programmer/designer must interpret the force levels into three-dimensional surfaces to create a model or mold. This interpretation is subject to error. Also, the foot contour is affected by its contact surface.
Whatever the precise merits, features and advantages of the above-cited references, none of them achieves or fulfills the purposes of the present invention. None of the above cited references generates a bodyweight supporting, pressure-equalized impression of the foot while it is dynamically functioning in a gait-simulated manner. All of the above cited references are subject to inaccurate impressions because of artificial influences such as designer's misinterpretations, technicians mis-held positions, flat impression or contact surfaces, distorted impression surfaces, over weightbearing or under weightbearing.
SUMMARY OF THE PRESENT INVENTION
It is an object of the present invention to achieve greater functional-accuracy and consistency in creating foot impressions for modeling of footwear and foot related appliances that generate user satisfaction.
Another object of the invention is to provide a method of forming a bodyweight-supporting, pressure-equalized impression of the foot generated by an apparatus that creates a dynamic state to the foot, simulating the gait cycle of human ambulation. The present invention accomplishes this objective by capturing an impression of the foot in a thin layer of impressionable material as the foot is moved in simulated ambulation. The ambulation is simulated on a gait simulation apparatus which comprises a container partially filled with granular particles and having a planar, elongate insert that is partially inserted within the granular particles. The insert is removable by pulling and when the insert is removed, the granular particles shift to fill the volume previously occupied by the insert. The subject foot and the impressionable material are placed on the gait simulation apparatus and bodyweight is applied to the foot. The apparatus supports the bodyweighted foot and impressionable material with granular particles in a loose state. Friction between the particles stabilizes and prevents movement. The insert is pulled out of the granular particles causing the particles, accompanying foot and impressionable material to shift as they fill the volume previously occupied by the insert. Friction between the particles is broken upon the shifting allowing the foot and mold material to progressively settle into a new supported position that provides a very even pressure upon the entire foot surface, regardless of tissue density. The movement of the foot simulates the human gait cycle characteristic of progressive heel to toe surface contact with a simultaneous adduction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevation view of the apparatus of the present invention to make an impression of a foot in a dynamic state that simulates the human gait cycle.
FIG. 2 is a plan view of the base platform of the above mentioned apparatus.
FIG. 3 is a plan view of the above mentioned apparatus.
FIG. 4 is an exploded section view of the molding box of the above mentioned apparatus.
FIG. 5 is a plan view of the elastic lid of the above mentioned apparatus.
FIG. 6 is a side elevation view of the above mentioned apparatus, except for the left side of the base platform which is sectioned off.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of the present invention will now be described in connection with FIGS. 1-6. With references now to the figures wherein like reference characters designate like or similar parts throughout the several views.
FIG. 1 is a front elevation view of the apparatus of the present invention to make an impression of a foot in a dynamic state that simulates the human gait cycle. The impression is done in the molding box 1 of the base platform 3. The base platform 3 is divided into three parts and is intended for the client, whose feet are the subject, to stand on. The client will stand on the top left side 13 of the base platform 3 while the right foot is placed on the central molding box 1. In turn, the client will stand on the top right side 14 of the base platform 3 while the left foot is placed on the central molding box 1. The two top sides 13 and 14 of the base platform 3 are at a higher elevation than the molding box 1 for the purpose of directing more weight to the foot on the molding box 1. The center of the base platform 3 has a molding box 1 containing granular particles 8 in a loose state (FIGS. 3 and 4), preferably silica sand in grade thirty. When a client's foot is gently placed on the leveled surface of the particles 8, the client will find that when weight is placed upon the foot, the particles 8 are firm and stable with very little deflection; so the surface of the particles 8 at the beginning remains essentially flat. This is believed to be due to friction between the granular particles 8. The present invention creates a downward vertical motion to the foot and particles 8 which begins at the heel and continuously progresses forward past the toes. The present invention also creates an adduction twist motion to the whole foot by internally pivoting the entire molding box 1 simultaneously along with the progressive downward vertical motion. The progressive heel-to-toe ground contact with simultaneous adduction twist is characteristic of a foot's motion during the human gait cycle. The part of the foot that is in motion is accompanied by the particles 8 that were initially supporting the foot. Once the particles 8 are put into motion, the initial friction between the granular particles 8 is broken, allowing the foot and particles 8 to settle together in a new anatomically supportive position. It is believed that because the particles 8 are in a loose state and have had the initial friction that binds them together broken, they are easily displaced by the pressure of the foot until the friction between the particles creates a uniform resistance that is equal to the pressure; a point upon which the motion of the foot ceases because it is supported with uniform pressure. The new anatomically supported position is generated progressively, beginning at the heel and continuing forward past the toes. The motion that the present invention generates in the foot, a downward vertical drop progressing from heel toward and past the toes with an adduction twist is considered a gait-simulated motion because, although the foot goes through the dynamics of its gait, the client remains in a stationary position on the base platform 3. This is so that an impression can be achieved that records the shape of the foot as it progressed through the gait-simulation.
A thin, uniform-thickness layer of impressionable material 15 that transforms into a hardened state is placed directly to the foots plantar surface. The foot is placed on the particles 8 of the present invention with the impressionable material 15 between the foot and the particles 8. When the gait-simulated motion occurs and the foot achieves a new anatomically supported position, the impressionable material 15 captures an impression of the foot and duplicates its exact position. To prevent particles 8 from clinging to the impressionable material 15, an elastic membrane 2 (FIG. 5) is used between the impressionable material 15 and the particles 8. The elastic membrane 2 is preferably of latex rubber and is mounted with a frame around its perimeter to form a convenient lid, that is placed upon the molding box 1. The elastic membrane 2 also has a U shaped marking 16 on its surface to indicate correct foot placement, directly above and to the rear of the sliding insert 6. Another membrane 7, is installed below the particles 8 to separate the particles 8 from the moving parts of the molding box 1. This is illustrated in FIG. 4. This separating membrane 7 is also flexible but is preferably made of low friction polyethylene film. It is adhered to the molding box by a spleen 17 into a groove 18 on an inside perimeter of the molding box 1. In the front of the molding box 1 is an opening 12 through which the sliding insert 6 is inserted. When completely inserted, only the handle end of the insert 6 extends from the molding box 1 (FIG. 6). This end has a cutout 19 that forms a handle so that one's hand may be inserted for a grip to pull out the sliding insert and generate the gait-simulated motion to the foot that is the subject. The sliding insert 6 is preferably about 0.75 inch thick and of high density polyethylene. The empty volume that is remaining at the end of the sliding insert 6 as it is extended out of the molding box 1 is what generates the vertical downward motion to the particles 8 and foot. The end 20 of the sliding insert 6 is beveled at a forty-five degree angle so that the foot is dropped gently and also so that the sliding insert 6 is easily slid back into the molding box 1. All top edges of the sliding insert 6 are rounded and smoothed to reduce friction. On the bottom surface of the sliding insert 6 a torsional tracking groove 9 is routed in the shape of a Y (FIG. 3). The torsional tracking groove 9 controls the adduction twist of the gait-simulated motion. A steel guide pin 10 is firmly mounted to the base structure 3 (FIG. 2). The guide pin 10 passes through a cutout 4 in the molding box 1 that is large enough to allow movement of the molding box 1 without the guide pin 10 touching the sides of the cutout 4. The guide pin 10 inserts through the cutout 4 in the molding box 1 into the tracking groove 9 on the sliding insert 6 (FIG. 6). The molding box 1 is mounted to the base platform 3 with a ball bearing turntable 11 between them (FIGS. 2 and 6). The pivot point of the turntable 11 is situated approximately where the ankle joint is positioned on the foot to be molded. When the sliding insert 6 that is inserted into the molding box 1 is put into motion, the tracking groove 9 that is snugly fitted over the fixed guide pin 10 controls the twist motion that will pivot the entire molding box on the low-friction turntable 11, thus inducing a twist motion to the foot that is on the molding box 1. When the insert 6 is inserted completely into the molding box 1, the guide pin 10 is at the end of either the right or left tip of the Y shaped tracking groove 9. The tips of the Y are one inch off center of the sliding insert 6 which produces approximately five degrees of toe-out angle when in the fully inserted position. At first motion of the sliding insert 6 the tracking groove 9 is straight, which allows the heel to drop simulating first heel strike, as motion progresses toward the mid-foot the guide pin 10 is in the curved section of the tracking groove 9 and has begun the internal adduction twist to the molding box 1. As the motion reaches the toes, the guide pin 10 is in the bottom, single-slot part of the tracking groove 9, which straightens out again for the final toe-off portion of the simulated gait, and ends the internal twist. The molding box 1 finishes the movement in a straight ahead angle with no toe-out. When the sliding false bottom 6 is returned to the molding box 1 in preparation for the other foot to be molded, the guide pin 10 is guided to the opposite tip of the Y tracking groove 9 to present the proper toe-out position for the other foot. To prevent any side-to-side movement of the sliding insert 6, lateral resistance blocks 5 (FIG. 3), are attached to the bottom of the molding box 1 on both sides of the sliding insert 6.
It is believed that the pressure-equalized, anatomically supported position that is achieved by the invention creating a vertical downward motion in a foot progressively from heel to toe combined with a simultaneous internal adduction twist will generate excellent functionally-accurate molds of the foot to model footwear and appliances that generate user satisfaction. It is also believed that the invention can produce results of high consistency because: 1) a standard amount of weight (natural bodyweight) is placed on the foot to be molded; 2) a standard amount of motion is generated in the foot; 3) there is no technician contact with the foot that could misplace its position; and 4) the procedure is simple, reducing the chances for technician error.
ALTERNATE EMBODIMENTS
An alternate embodiment of the invention would be as described in the preferred embodiment except for the twist motion being abduction instead of adduction.
Another alternative would be as described in the preferred embodiment except for the motion would begin at the toes and progress past the heel. Opposite of the motion in the preferred embodiment.
Another alternate embodiment would be as described in the preferred embodiment except eliminating any twist.
Another alternate embodiment would be as described in the preferred embodiment except the guide pin 10 would be a motor driven guide gear, and the tracking groove 9 would be toothed to mesh with the gear. In this alternative the movement of the insert would be motorized.
Six other alternate embodiments, as listed below, are as described in the preferred embodiment except for the manner of causing the particles 8 to shift and break their friction. Another exception would be that the twist motion, if included, would also need to be achieved in another manner. In the following six alternatives it is assumed that the twist motion, if included, is motorized with electronic on and off switches that coordinate the correct timing of the twist in the gait cycle.
1. Causing the particles 8 to shift when a device inserted within the particles expands or contracts. An example of this would be elastic air chambers.
2. Causing the particles 8 to shift when a device inserted within the particles 8 shrinks or stretches. An example would be a progressive stretch membrane.
3. Causing the particles 8 to shift when accordion folded slats that are inserted within the particles are progressively unfolded.
4. Causing the particles 8 to shift when devices that are inserted within the particles 8 are progressively agitated or vibrated.
5. Causing the particles 8 to shift when vertically mobile blocks, bars or pins that are inserted within the particles 8 are moved in a progressive pattern.
6. Causing the particles to shift when a wave is generated in a planar surface that is inserted within the particles.
Another alternate embodiment would involve comparison studies between foot impressions generated with the preferred embodiment of the present invention and three dimensional foot information generated with various apparatus on a computer. In this alternative a correction factor would be applied to the original computer information so that the corrected computer information would duplicate an impression generated on the preferred embodiment of the present invention.
Another alternate embodiment would be as described in the preferred embodiment except for the capturing of the foot impression would be accomplished by a multitude of three-dimensional computer sensors imbedded in the separating membrane 7.
The foregoing description of the preferred embodiment of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto. | A method of forming a bodyweight supporting, pressure-equalized impression of the foot, generated by an apparatus that creates a dynamic state to the foot, simulating the gait cycle of human ambulation. The foot and impressionable material are placed on granular particles within a container. The container is mounted to a base with a turntable between them. A planar, elongate insert is partially inserted within the granular particles. The base has a guide pin that fits through an opening in the container into a track in the insert. The insert is removable by pulling and when the insert is removed the granular particles and accompanying foot shift to fill the volume previously occupied by the insert. The shifting movement begins at the heel of the foot and continues progressively past the toes. Also, as the insert is removed the container pivots on the turntable in adduction. The inserts track slides along the guide pin controlling the amount and timing of the twist. The impressionable material captures an impression of the foot as it progressively settles into a new supported position in a manner that simulates the human gait cycle. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to apparatus for applying liquid coating material on a moving web of paper, and in particular to an apparatus of the trailing blade type which has an improved structure for applying very uniform coat weights of material on a web of paper.
Conventional coaters of the trailing blade type include means for applying coating material to a paper web that is usually supported and carried by a resilient backing roll, together with a flexible coater or doctor blade located on the trailing side of the applicator, which serves to doctor or level the applied coating. In general, an excess of coating material is applied onto the web and the coater blade then meters or removes the excess while uniformly spreading the coating onto the web surface.
In recent years it has become desirable to produce papers having a minimum amount of coating. To achieve low coat weights with conventional trailing blade equipment it is necessary to increase the pressure of the coater blade against the web, which results in a high rate of wear of the blade and necessitates more frequent blade replacement. High blade pressure also increases the possibility of web breaks and streaking caused by foreign particles caught between the blade and web.
Conventional coaters employ a relatively long dwell or soak time, which is the time interval between initial application and final blading of the coating. As a result, the water portion of the coating composition, as well as the water soluble or dispersible materials contained therein, migrate into the moving web at a more rapid rate than the pigment and eventually cause an undesirable imbalance in the coating constituents and their rheological properties. Long soak periods are also incompatible with the application of successive web coats without intervening drying, because the successive coats tend to migrate into and contaminate the previous coat.
The foregoing problems are discussed in U.S. Pat. No. 3,348,526, issued to Neubauer, wherein a narrow stream of coating is extruded onto an inverted trailing blade that defines a nip region with a supported web. The coating application is such that the coating material is unpressurized after leaving an orifice and being supported on the blade, and the leading side of the coating material stream is exposed to the environs in the zone of application. Since the coating is bladed substantially immediately after application, soak times are kept to a minimum.
To overcome the disadvantages of the aforementioned applicators in applying lightweight coatings on paper, there has been developed a short dwell time applicator as disclosed in U.S. Pat. No. 4,250,211, issued to Damrau et al and assigned to the assignee of the present invention. In that applicator, coating material is introduced in excess into a relatively narrow application zone for being applied on a web carried therethrough. A forward wall of the applicator defines a relatively narrow gap with the web at the upstream end of the application zone, and excess material in the zone overflows through the gap and forms therein a liquid seal, so that coating material in the zone and as applied to the web is maintained under pressure. The speed of the web is adjusted for a relatively short dwell time, and a flexible coater blade doctors the web at the downstream end of the zone, thereby removing excess material from the web and uniformly spreading the material on the web. In consequence of the short dwell time of the pressurized application of coating material on the web, an appropriate yet lightweight amount of coating may be applied without need for high blade pressures.
A requirement in use of conventional applicators, as well as an applicator of the type disclosed in U.S. Pat. No. 4,250,211, is that coating material must be uniformly distributed to the web, so that the coating material is applied very uniformly and doctored evenly to produce a uniform coat weight on the web. Nonuniformity in weight of the coating material impairs the quality of the resulting coated paper, and may even render it unsatisfactory for its intended purpose.
SUMMARY OF THE INVENTION
In accordance with one aspect of the invention, there is provided an improved applicator for applying coating liquid to a moving web of paper. The applicator is of a type including an elongate body defining an elongate chamber therein with an elongate opening thereto positionable adjacent to and transversely across the web, and means for introducing coating liquid under pressure into the chamber for being directed through the opening and onto the web. The improvement is characterized in that the chamber is generally teardrop shaped, has a curved wall opposite from the opening and front and rear walls which converge from the curved wall toward the opening.
The means for introducing comprises an elongate and tubular distribution header in and longitudinally along the chamber and having a plurality of spaced and longitudinally aligned outlet passages, and means for flowing coating liquid under pressure into opposite ends of said distribution header. The curved chamber wall is preferably semicircular, and the distribution header is rotationally oriented so that the outlet passages direct coating liquid toward and against the curved wall, which deflects the coating liquid for flow around opposite sides of the distribution header and through the chamber to and through the opening.
In accordance with another aspect of the invention, there is provided an improved applicator for applying coating liquid to a moving web of paper, wherein the applicator is of a type comprising an elongate body having front and rear relatively movable walls, a base wall between the front and rear walls and end walls at opposite ends thereof. The front, rear, base and end walls define a chamber therebetween and ends of the front and rear walls, generally opposite from the base wall, are spaced apart and define an elongate opening from the chamber positionable adjacent to and transversely across the web, and means is provided for introducing coating liquid under pressure into the chamber for being directed through the opening and onto the web. The improvement is characterized in that the front wall is movable relative to and away from all of the rear, base and side walls to open the chamber, and an integral and resilient seal means is between the front wall and each of the end and base walls for sealing the front wall thereto when the same are moved together to close the chamber.
In accordance with a further aspect of the invention, in an applicator of the general type there is provided a plurality of conduits extending longitudinally along the body for conveying a heat transfer fluid in contact with the body, and means for flowing a temperature controlled heat transfer fluid through the conduits to selectively thermally deflect the body to maintain the elongate opening straight between opposite ends thereof despite bowing or lateral deformations that would occur in the absence of the heat transfer fluid, so that very uniform coat weight profiles may be maintained.
The foregoing and other objects, advantages and features of the invention will become apparent upon a consideration of the following detailed description, when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional, side elevation view of a short dwell time applicator for applying a liquid coating material to a moving web of paper, illustrating the configuration and arrangement of an improved coating material supply chamber and distribution header for very uniformly distributing coating material into an application zone and onto a web of paper moving through the zone to produce a very uniform coat weight on the web;
FIG. 2 is similar to FIG. 1, except that a front wall of the applicator is shown in an open position accommodating access to the chamber for cleaning the same, and
FIG. 3 is a partial cross-applicator view taken substantially along the lines 3--3 of FIG. 2, illustrating further details of the distribution header and chamber, as well as an improved seal structure for establishing a fluid tight connection with the front wall when it is closed.
DETAILED DESCRIPTION
The drawings illustrate an applicator or coater portion of a paper coating machine, which embodies the teachings of the present invention. Referring to FIG. 1 the applicator, indicated generally at 20, is elongate and extends parallel to and coextensively with a movable support or backing roll 22 which rotates in the direction shown by an arrow 24 and supports a web of paper 26 during its travel through an application zone. The applicator has rear and front walls 28 and 30 forming a coating material supply chamber 32 therebetween for reception of liquid coating material under pressure, and the walls converge upwardly toward one another and define a narrow outlet orifice or metering slot 34 which extends upwardly adjacent to, transversely across and facing the web support surface of the roll 22.
The applicator also includes a main support beam, indicated generally at 36, extending parallel to and coextensively with the backing roll 22. The applicator rear wall 28 defines a front wall of the main beam, which also has a top wall 38 formed into an upwardly extending lip at its forward end. A flexible doctor or coater blade 40 at the downstream end of the application zone is held against a rearward surface of the lip by a pneumatic tube 42 contained within a channel in a support member 44, and the tube is expandable by the introduction of fluid under pressure therein to press against the blade. The blade extends upwardly into engagement with the web 26 supported on the backing roll and serves to meter and level the coating applied on the surface of the web. A tip 46 of the blade is urged or loaded against the web by a second pneumatic tube 48 contained within a channel in an upper support member 50, and the amount of coating applied to the web is influenced by the force of the blade tip against the web.
The front wall 30 is pivotally mounted relative to the rear wall 28 to permit the chamber 32 to be opened for cleaning, as shown in FIG. 2. To that end, the front wall is curved rearwardly at 52, beneath the curve the wall is connected by a hinge 54 to a lower applicator wall 56, and a lower end of the front wall is connected by a hinge 58 to a piston rod 60 of a pneumatic cylinder 62. The cylinder in turn is pivotally connected by a bracket 64 to a main beam bottom wall 66, whereby actuation of the cylinder pivots the front wall between a position closing the chamber (FIG. 1) and a position opening the chamber (FIG. 2).
An elongate orifice plate holder 68 extending transversely of the applicator is mounted on an upper end of the front wall 30 and defines with the front wall and upwardly opening elongate slot 70. An elongate orifice plate 72 is received within the slot transversely of the applicator, rests at its lower end on the bottom of the slot and is releasably secured in the slot by a pneumatic tube 74 received in a channel through the orifice plate holder. The orifice plate converges toward the roll supported web, and has a free upper edge 76 which is juxtaposed to but spaced slightly from the web, such that a space or gap 78 between the edge and the web at a forward, leading or upstream end of the application zone is relatively small and less than one inch. As will be described, excess coating material introduced into the application zone from the chamber 32 and through the metering slot 34 overflows from the zone through the gap 78 and forms a liquid seal in the gap at the forward end of the zone, thereby enabling pressurized application of coating material onto the web in the zone. A splash plate 80 extending downwardly and outwardly from a forward edge of the orifice plate holder guides liquid coating material flowing through the gap into a trough (not shown) for collection and recirculation.
The two side ends of the coating material supply chamber 32 are sealed by end plates 82 and 84 having respective brackets 86 and 88 for mounting the end plates to the rear wall 28 (FIG. 3). At the two side ends of the application zone, the spaces between the coater blade 40 and the orifice plate 72 are sealed off by edge dams 90 (only one of which is shown), which seal with the upper ends of the front wall 30 and forward lip of the wall 38, as well as with the orifice plate, doctor blade and roll supported web 26, thereby to define a generally closed coating material application zone 92 downstream from the metering slot 34 and between the web, doctor blade and gap 78.
To the extent described, the applicator is generally of the type disclosed in detail in aforementioned U.S. Pat. No. 4,250,211, issued to the assignee of the present invention, the teachings of which are incorporated herein by reference. For a more specific description of the applicator, reference is made to that patent.
In operation of the applicator to the extent described and as taught by U.S. Pat. No. 4,250,211, coating liquid is introduced into the chamber 32 under sufficient pressure and in sufficient quantity to completely fill the chamber, the metering slot 34 and the application zone 92 defined by the doctor blade 40, the orifice plate 72 and the end dams 90, to cause a continuous, copious flow of coating material reversely of the direction of web travel through the narrow space or gap 78 defined between the upper edge 76 of the orifice plate and the web. This forms a liquid seal between the edge and the web and causes the coating liquid to be applied to the web in a very narrow transverse band under a constant positive pressure. The copious excess of coating liquid that flows through the gap 78 reversely of the direction of web travel forms a nonabrasive liquid seal with the web at the upstream or forward end of the coating application zone; causes the coating liquid in the zone to be maintained under pressure and to be applied to the web under pressure; seals off the forward edge of the zone against entry of air and foreign matter; strips air from the high speed web and prevents such air from causing streaks or skips in the coating on the web; and causes the coater blade 42 to doctor the coating liquid while the liquid is held under pressure.
In paper coaters of the short dwell time type such as described above and in U.S. Pat. No. 4,250,211, it is important that the applicator incorporate a coating material supply chamber and a coating material distribution header of a design such that coating material is uniformly distributed to and applied on the web and doctored evenly to produce a uniform coat weight. Accordingly, in accordance with one aspect of the invention the coating material supply chamber 32 is of generally teardrop shape and defined within the front wall 30 and an elongate J-shaped member extending transversely of the applicator. The J-shaped member has a planar rear wall 94 abutting the rearward wall 28 and a semicircular lower wall 96 which terminates at an elongate support 98 having an upper semicircular surface 100 which continues the curve of the bottom wall 96. The inside walls of the chamber 32 are smooth to prevent coating buildup, and the tapered side walls 94 and 30 lead into the metering slot 34, the result being that the opposing converging walls tend to gradually accelerate the flow of coating material to the metering slot.
In addition to the teardrop shape of the chamber 32, according to another aspect of the invention there is provided an improved distribution header within the chamber. The distribution header, which is tubular, elongate and extends transversely through the chamber, receives coating liquid under pressure at its opposite ends through supply lines 104 and 106 (FIG. 3), and has a plurality of spaced outlet openings or passages 108 formed therethrough longitudinally therealong. Taken in conjunction with the size and spacing of the outlet openings, on narrow coaters of approximately 200 inches and narrower a three inch diameter distribution header has been found to be sufficient, while with wider coaters on the order of 300 inches the distribution header may need to be about five inches in diameter to convey the larger flows of coating material and uniformly distribute the coating on the web. The semicircular chamber wall 96 and surface 100 are concentric throughout their extent with the distribution header, and the distance between the concentric surfaces is on the order of 0.375" to 0.500", depending on the viscosity of the coating material used. It is contemplated that the dimension would be about 0.375" for low viscosity coating materials (e.g., 3000 cps at 20 RPM Brookfield) and about 0.500" for high viscosity coating materials (e.g., 8000 cps at 20 RPM Brookfield). However, it has been found that a 0.375" dimension is usually optimum.
The distribution header 102 is preferably rotationally oriented within the chamber 32 so that the outlet openings 108 discharge coating material downwardly against the circular bottom wall 96. In consequence, the flow of coating material from the distribution header is uniformly spread out and distributed to opposite sides of the header, and flows around the header into the upper tapered portion of the chamber and thence through the metering slot 34 into the application zone 92 for being very uniformly applied onto the paper web and doctored evenly. The downwardly directed flow also flushes the concentric surfaces to maintain the chamber continuously scoured and clean during operation.
The spacing between the distribution header outlet openings 108 is normally about 10.75" center to center, although the dimension can vary about 1.0" depending on the coating material formulation and rheology used. The diameter of the openings preferably ranges from about 0.625" to 0.875", although the use of 0.750" diameter openings has been found to be particularly advantageous. All of the openings need not be of the same diameter, and several may be either larger or smaller toward the center of the distribution header to facilitate uniform distribution with some coating formulations. The distribution header is rotatably adjustable within the chamber 32 to direct the flow of coating material from the openings in any direction radially outwardly from the header, although it is contemplated that in normal operation of the applicator the direction of discharge will usually be downward. Opposite ends of the distribution header are provided with collars 110 and 112, which can be removed to accommodate lateral removal of the distribution header from the chamber through the end plates should there be a need to change the size of the outlet openings or their spacings.
A further aspect of the invention relates to a structure for sealing the movable front wall 30 with each of the end plates 82 and 84 and the elongate support 98 to seal the chamber 32, and to that end seal retaining grooves 114, 116 and 118 are respectively formed in and along the front faces of the end plates 82 and 84 and the elongate support 98. As seen in FIG. 3, the three grooves are continuous and together are generally U-shaped or configured as an open sided rectangle, and from FIGS. 1 and 2 it is seen that the grooves lie in a common plane and opposite side walls of each groove define a generally triangular protuberance. The grooves are adapted to receive a unitary, U-shaped and square cross sectioned elastomer seal 120, such as of neoprene or Buna N, and the shape of the grooves are such that they hold or grasp the sides of the seal and retain it without need for adhesives or retaining devices. Consequently, a continuous square cross section seal strip 120 inserted into the grooves 114, 116 and 118 provides a fluid tight connection between the movable front wall, the end plates and the elongate support without need for joints or splices in the seal. The seal strip preferably has a continuous circular passage formed therethrough along its length to facilitate insertion of the seal into the grooves, and the result is that the structure provides a simplified, fluid tight seal for the coating material supply chamber when the front wall is closed, so that in operation of the applicator there is no or at most minimal leakage of coating material from the chamber.
As is known, because of the relatively large transverse extent of paper coating applicator, if there are slight deviations in manufacturing the same or perhaps as a result of heating during use, it often happens that the applicator deflects or bows between its side ends, resulting in nonuniform doctor blade pressure on the paper web and attendant nonuniform coating material weight. Accordingly, the invention also contemplates providing two channels 122 and 124 along and adjacent to a lower inner surface of a back wall 126 of the main beam 36, and a pair of channels 128 and 130 along and adjacent to the upper end of the rearward wall 28. Means (not shown) are also provided for introducing cooled and/or heated fluid medias into the various channels, so that by controlling the temperature of the medias the applicator and main beam can be deflected in a controlled manner to obtain an applicator straightness from side to side of the web and thereby produce uniform coat weights even with wide coater heads. Although not shown, similar channels may be provided along the top and bottom main beam walls 38 and 36 to also enable controlled deflection of the main beam along a plane generally perpendicular to the plane of deflection afforded by the channels 122, 124, 128 and 130.
While embodiments of the invention have been described in detail, various modifications and other embodiments thereof may be devised by one skilled in the art without departing from the spirit and scope of the invention, as defined in the appended claims. | An improved paper coating applicator has a body portion defined by forward and rearward relatively movable walls defining a chamber therebetween with an elongate opening thereto positionable generally below, adjacent to and transversely of a paper web, the chamber receiving coating liquid and directing the same generally upwardly through the opening and onto the web. According to one aspect of the improvement, the chamber and a distribution header for introducing coating material therein are of a design enhancing a very uniform application of coating material onto the web. In another aspect, a unique seal structure provides a secure, fluid tight connection between the front and rear walls. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present non-provisional U.S. patent application claims the benefit of the filing of provisional U.S. patent application Ser. No. 60/527,261 filed 3 Dec. 2003 and having the same title as the present document, the contents of said provisional application are hereby incorporated herein in their entirety.
[0002] This application also relates to and hereby incorporates by reference the contents of three non-provisional U.S. patent applications; namely, application Ser. No. 10/376,981 filed 28 Feb. 2003 (Atty Dkt. P-10805.00) entitled “METHOD AND APPARATUS FOR ASSESSING LEFT VENTRICULAR FUNCTION AND OPTIMIZING CARDIAC PACING INTERVALS BASED ON LEFT VENTRICULAR WALL MOTION;” application Ser. No. 10/377,207 filed 28 Feb. 2003 (Atty Dkt. P-11229.00) which received a Notice of Allowance mailed 5 Nov. 2004 and is entitled “METHOD AND APPARATUS FOR OPTIMIZING CARDIAC RESYNCHRONIZATION THERAPY BASED ON LEFT VENTRICULAR ACCELERATION;” application Ser. No. 10/803,570 filed 17 Mar. 2004 (Atty Dkt. P-11471.00) entitled “APPARATUS AND METHODS OF ENERGY EFFICIENT, ATRIAL-BASED BI-VENTRICULAR FUSION-PACING;” and application Ser. No. 10/631,551 filed 30 Jul. 2003 (Atty Dkt. P-10306.00) entitled “METHOD OF OPTIMIZING CARDIAC RESYNCHRONIZATION THERAPY USING SENSOR SIGNALS OF SEPTAL WALL MOTION.”
FIELD OF THE INVENTION
[0003] The present invention relates to the field of cardiac therapy. In particular, the present invention provides methods and apparatus for optimizing an atrioventricular (A-V) interval based on measuring or obtaining one or more physiologic parameters of a patient. The parameters may be obtained using echocardiographic equipment and the like to enhance cardiac therapy delivery, such as a dual chamber pacing therapy and cardiac resynchronization therapy (CRT), among others.
BACKGROUND OF THE INVENTION
[0004] Those skilled in the art of diagnosing cardiac ailments have long understood that certain patients, in particular heart failure (HF) patients, suffer uncoordinated mechanical activity wherein the myocardial depolarization and contraction of the atria and ventricles (i.e., right and left) occur in an uncoordinated fashion. Such uncoordinated motion can cause a decrease in stroke volume and/or cardiac output (CO), among other detrimental effects. Recently a variety of techniques have been proposed and practiced for minimizing such uncoordinated motion.
[0005] These prior art techniques for minimizing uncoordinated myocardial motion include CRT optimization. One known way to attempt to optimize CRT delivery involves Doppler echocardiographic imaging of ventricular contractions while adjusting interventricular pacing stimulus delivery (i.e., V-V timing). The optimized V-V timing is the interventricular timing that produces the least amount of visibly perceptible dyssynchrony. For successful CRT delivery, the A-V intervals typically are programmed to a magnitude less than the intrinsic atrial-to-ventricular (P-R) interval for a given subject to help ensure bi-ventricular CRT delivery.
[0006] An apparatus for delivering CRT includes implantable pulse generator (IPG) with or without high-energy cardioversion/defibrillation therapy capability. An IPG adapted for CRT delivery typically includes three medical electrical leads coupled to myocardial tissue. A first lead typically coupled to the right atrium, a second lead typically coupled to the right ventricle, and a third lead typically coupled to the left ventricle (often via the coronary sinus or great vein). That is, the third lead couples to a location on the free wall of the left ventricle.
[0007] Thus, as is known in the art, based at least in part on acute echocardiographic measurement an IPG configured for CRT delivery provides only a limited ability to adjust operative A-V and to a slightly greater degree, V-V intervals. Thus, a need exists in the art for appropriately optimizing electrical cardiac pacing stimulus delivery between the atria and the left ventricle (LV) and/or the right ventricle (RV) in an effort to enhance hemodynamics and other benefits of optimized pacing therapy delivery. When successfully and optimally delivered, certain pacing therapies, such as bi-ventricular CRT, are known to increase CO and may, over time, cause a phenomenon known in the art as “reverse remodeling” of the LV and RV (and/or other beneficial) physiologic changes to the patient's heart.
SUMMARY OF THE INVENTION
[0008] The present invention addresses the above described needs by providing means for predicting appropriately timed electrical stimulation of one or both ventricular chambers based on inter-atrial delay and/or characteristics (measured or estimated) of the left ventricular (LV) chamber (e.g., filling characteristics, end-diastolic volume or “LVEDV,” end-systolic volume or “LVESV,” etc.). The present invention provides for quickly and easily optimizing the atrio-ventricular (A-V) pacing intervals to enhance cardiac resynchronization therapy (CRT) delivery, among other advantages.
[0009] Although some practitioners optimize the A-V interval in all of their patients following their reception of a CRT device, the majority of practices send their patient for optimization only if they do not clinically respond to the therapy with a nominal device setting. A major issue that remains is that of reimbursement for the optimization procedures, since in the U.S. echocardiographic optimizations are typically only reimbursed for needed A-V optimization following a three-month (90-day) post-implant time-frame. Additionally, the inventive approach presented herein complements the practice wherein patients are initially screened using echocardiography to determine if they would respond to CRT (presence of mechanical dyssynchrony). During the same echocardiography session, the inter-atrial mechanical delay and LV volume measurements (or estimates) can readily be utilized to program A-V timing for a CRT device following implant.
[0010] One feature of the present invention provides an algorithmic approach to determining which patients may benefit from a programmed A-V interval different than a nominal setting (e.g., other than 100 ms), and provides a suggested A-V interval for these patients. A premise behind the invention is an assumption that a patient has an A-V of 100 ms (the average in the MIRACLE trial). Then, by adding or subtracting from that nominal, assumed value—based on current or recently obtained patient cardiac information (e.g., dimensions, inter-atrial delays, etc.) computation (or look-up) of a corrected, operative A-V interval results.
[0011] By way of background, the MIRACLE trial data was acquired in blinded fashion in which patients were individually optimized based on maximizing trans-mitral filling. The final histogram of the programmed A-V delays for the entire population resembles a Normal distribution centered at an A-V interval of 100 ms. The standard deviation of the A-V delay was 20 ms. Due in part to measurement uncertainties, the inventors posit that alteration of an A-V interval by 20 ms or less has minimal impact on patient outcome or clinical response, although refining, or tuning, operative A-V intervals by less than 20 ms is considered within the metes and bounds of the present invention. That is, considerable debate exists regarding the importance of A-V intervals, with one extreme of the debate essentially believing in leaving the device settings at a nominal setting (e.g., 100 ms), and the other extreme of the debate believing that periodic automatic A-V interval adjustment is necessary to account for rest and elevated cardiac states. From retrospective analysis of the MIRACLE and MIRACLE ICD data, 66% of patients were set at 100+/−20 ms (mean +/−1 std. dev.). A relevant question therefore becomes whether patients at the extremes can be identified and pacing interval timing programmed more appropriately. The approach of setting the A-V timing by placing patients into discrete “bins” of A-V settings may be of clinical importance versus a nominal A-V=100 ms approach. Based on retrospective data analysis of the MIRACLE trial database, LV size and inter-atrial delays were major factors in determining the final optimal A-V timing interval. Patients with long inter-atrial mechanical delays had significantly longer A-V delays. Patients with smaller LV dimensions at baseline had significantly longer A-V delays.
[0012] The algorithm operates using data regarding incidence (and duration) of inter-atrial delays (mechanical or electrical), estimate of relative LV size, and optionally filling characteristics of the atrial and/or ventricular chambers. The algorithm can be used to calculate an operative A-V delay interval based on an original nominal setting (e.g., setting of 80 ms, 90 ms, 100 ms, 110 ms, etc.) and either adding or subtracting increments of A-V timing based on the physiologic information collected for a given patient. Alternatively, the operative A-V delay interval can be generated iteratively. In its simplest form, a constant amount could be added or subtracted from the nominal setting if one or more of the parameters of interest puts the patient in the upper or lower quartile of cardiac performance.
[0013] In addition, in a more advanced version of the algorithm according to the present invention, a linear or higher order formula can be employed to compute the amount of shortening or lengthening of the A-V interval based on the extent (or magnitude) of ventricular size or inter-atrial delay. These two measures and others can be employed in combination and need not be sequentially implemented (as depicted hereinabove). Such use could include multiparametric equations or more simply for example, a multidimensional so-called “lookup table” (LUT) or other data structure capable of correlating discrete parameters in which an optimal A-V interval (or adjustment thereof) is listed or “mapped” for each combination of the parameters (e.g., inter-atrial delay, ventricular size, chamber filling time, etc.). Such a LUT can be used to correlate discrete heart rate (or ranges of heart rate) to further refine, or tune, the operative A-V delay interval. Thus implemented the algorithm can be embodied in software on a programmer and prompt the clinician or user for echocardiographic- or electrical-derived data relating to the inter- or intra-atrial delay, LV dimensions (e.g., LVEDV, LVESV, etc.). This data would then be processed by a processor running the program to generate an optimal A-V interval based on a model derived from a physiologically similar patient population.
[0014] In one embodiment, one generalized technique according to the present invention utilizes baseline echocardiographic data (or any baseline physiologic data) to predict optimal device programming based on a known model derived from a specific patient population, such a clinical trial (e.g., the MIRACLE trial, MIRACLE ICD trial).
[0015] In one form of the present invention, an inter-atrial mechanical delay is measured automatically by electrode pairs operatively coupled to an implantable medical device (e.g., P-wave duration from a far field ECG, intra-atrial conduction delay if two atrial leads available) the device then calculates a suggested A-V interval based on the detected inter-atrial delay. According to this form of the invention, continuous or interative A-V interval tuning can be performed while a patient performs activities of daily living (ADL) such as sleeping, sustained physical exertion, driving, etc. With respect to measuring inter-atrial delay a right atrial (RA) lead and a LV lead disposed through the coronary sinus with at least one electrode adjacent the left atria (LA) can be used to sample and adjust A-V interval timing based on essentially real-time data acquisition.
[0016] In one form of the invention, a properly-timed single ventricular pacing stimulus produces bi-ventricular synchrony (sometimes called “fusion-based CRT delivery”). Depending at least in part upon the conduction status of a patient, such fusion-based pacing may require what was termed pre-excitation of one ventricle (e.g., the LV) as further described in the co-pending application Ser. No. 10/803,570 to Burnes and Mullen, cross-referenced above and incorporated by reference in its entirety herein.
[0017] Thus, the present invention provides novel methods and apparatus implemented to minimize uncoordinated cardiac motion, among other advantages.
[0018] With respect to the closed-loop CRT optimization methods and apparatus, in addition to detecting (diagnosing) cardiac mechanical dysfunction using echocardiographic techniques and using data that correlates LVEDV, LVESV, filling characteristics and/or inter-atrial delay with A-V interval provides automatically optimized, dynamically-adjustable CRT pacing modalities. In essence, one basic embodiment of the present invention provides A-V interval timing to maximize the benefits afforded by chronic CRT delivery.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 depicts an exemplary implantable, multi-chamber cardiac pacemaker coupled to a patient's heart via transvenous endocardial leads.
[0020] FIG. 2 is a schematic block diagram of the multi-chamber pacemaker of FIG. 1 capable of delivering a resynchronization therapy.
[0021] FIG. 3 is a flow chart providing an overview of a method for optimizing cardiac pacing intervals.
[0022] FIG. 4 is a flow chart summarizing steps included in a method for determining an optimal A-V interval.
DETAILED DESCRIPTION OF THE INVENTION
[0023] As indicated above, the present invention is directed toward providing a method and apparatus for optimizing ventricular function and selecting cardiac pacing intervals for the purposes of restoring ventricular synchrony based on inter- and/or intra-atrial delay, ventricular filling characteristics and/or physiologic dimensions of one or both ventricles. The present invention is useful in optimizing atrial-ventricular, inter-atrial and inter-ventricular pacing intervals during cardiac resynchronization therapy (CRT) used for treating heart failure. The present invention is also useful in selecting pacing parameters used during temporary pacing applied for treating post-operative uncoordinated cardiac chamber (e.g., atrial and/or ventricular) motion. As such, the present invention may be embodied in an implantable cardiac pacing system including a dual chamber or multichamber pacemaker and associated set of medical electrical leads. Alternatively, the present invention may be embodied in a temporary pacing system including an external pacing device with associated temporary pacing leads.
[0024] FIG. 1 depicts an exemplary implantable, multi-chamber cardiac pacemaker 14 in which the present invention may be implemented. The multi-chamber P 20171 . 00 PATENT pacemaker 14 is provided for restoring ventricular synchrony by delivering pacing pulses to one or more heart chambers as needed to control the heart activation sequence. The pacemaker 14 is shown in communication with a patient's heart 10 by way of three leads 16 , 32 , 52 . The heart 10 is shown in a partially cut-away view illustrating the upper heart chambers, the right atrium (RA) and left atrium (LA) and septal wall (SW) disposed therebetween, and the lower heart chambers, the right ventricle (RV) and left ventricle (LV) and the septal wall (SW) disposed therebetween, and the coronary sinus (CS) extending from the opening in the right atrium laterally around the atria to form the great cardiac vein 48 including branches thereof.
[0025] The pacemaker 14 , also referred to herein from time to time as an implantable pulse generator (IPG) or an implantable cardioverter-defibrillator (ICD), is implanted subcutaneously in a patient's body between the skin and the ribs. Three transvenous-endocardial leads 16 , 32 , 52 connect the IPG 14 with the RA, the RV and the LV, respectively. Each lead has at least one electrical conductor and pace/sense electrode. A remote indifferent can electrode 20 is formed as part of the outer surface of the housing of the IPG 14 . The pace/sense electrodes and the remote indifferent can electrode 20 can be selectively employed to provide a number of unipolar and bipolar pace/sense electrode combinations for pacing and sensing functions.
[0026] The depicted bipolar endocardial RA lead 16 is passed through a vein into the RA chamber of the heart 10 , and the distal end of the RA lead 16 is attached to the RA wall by an attachment mechanism 17 . The attachment mechanism may be active or passive as is known in the art and as may be later developed. A helix or tined lead may be used as is known in the art, to adapt the distal end of a lead for relatively permanent fixation to myocardial tissue. The bipolar endocardial RA lead 16 is formed with an in-line connector 13 fitting into a bipolar bore of IPG connector block 12 that is coupled to a pair of electrically insulated conductors within lead body 15 and connected with distal tip RA pace/sense electrode 17 and proximal ring RA pace/sense electrode 21 provided for achieving RA pacing and sensing of RA electrogram (EGM) signals.
[0027] In accordance with a triple chamber embodiment of the present invention, a coronary sinus lead 52 capable of stimulating the left ventricle is preferably of a relatively small size and diameter such that it may be passed through the coronary sinus and entering a vessel branching from the great cardiac vein and able to be steered to a left ventricular pacing site.
[0028] The depicted positions of the leads and electrodes shown in FIG. 1 in or about the right and left heart chambers are approximate and merely exemplary. Furthermore, it is recognized that alternative leads and pace/sense electrodes that are adapted for placement at pacing or sensing sites on or in or relative to the RA, LA, RV and LV may be used in conjunction with the present invention.
[0029] Bipolar, endocardial RV lead 32 passes through the RA into the RV where its distal ring and tip RV pace/sense electrodes 38 , 40 are adapted for fixation to myocardial tissue by a distal attachment mechanism 41 . The RV lead 32 is formed with an in-line connector 34 fitting into a bipolar bore of IPG connector block 12 that is coupled to a pair of electrically insulated conductors within lead body 36 and connected with distal tip RV pace/sense electrode 41 and proximal ring RV pace/sense electrode 38 provided for RV pacing and sensing of RV EGM signals.
[0030] In the illustrated embodiment of a triple chamber IPG capable of delivering CRT, a unipolar or bipolar or multipolar endocardial LV CS lead 52 is passed through the RA, into the CS and further into a cardiac vein to extend the distal LV CS pace/sense electrode 50 alongside the LV chamber to achieve LV pacing and sensing of LV EGM signals. The LV CS lead 52 is coupled at the proximal end connector 54 fitting into a bore of IPG connector block 12 . A small diameter unipolar lead body 56 is selected in. order to lodge the distal LV CS pace/sense electrode 50 deeply in a cardiac vein branching from the great cardiac vein 48 .
[0031] In a four chamber embodiment, LV CS lead 52 could bear a proximal LA CS pace/sense electrode positioned along the lead body to lie in the larger diameter coronary sinus adjacent the LA for use in pacing the LA or sensing LA EGM signals. In that case, the lead body 56 would encase an insulated lead conductor extending proximally from the more proximal LA CS pace/sense electrode(s) and terminating in a bipolar connector 54 .
[0032] FIG. 2 is a schematic block diagram of an exemplary multi-chamber IPG 14 , such as that shown in FIG. 1 , that provides delivery of a resynchronization therapy and is capable of processing atrial and/or ventricular signal inputs. The IPG 14 is preferably a microprocessor-based device. Accordingly, microprocessor-based control and timing system 102 , which varies in sophistication and complexity depending upon the type and functional features incorporated therein, controls the functions of IPG 14 by executing firmware and programmed software algorithms stored in associated RAM and ROM. Control and timing system 102 may also include a watchdog circuit, a DMA controller, a block mover/reader, a CRC calculator, and other specific logic circuitry coupled together by on-chip data bus, address bus, power, clock, and control signal lines in paths or trees in a manner known in the art. It will also be understood that control and timing functions of IPG 14 can be accomplished with dedicated circuit hardware or state machine logic rather than a programmed microcomputer.
[0033] The IPG 14 includes interface circuitry 104 for receiving signals from sensors and pace/sense electrodes located at specific sites of the patient's heart chambers and delivering cardiac pacing to control the patient's heart rhythm and resynchronize depolarization of chambers of a patient's heart. The interface circuitry 104 therefore includes a therapy delivery system 106 intended for delivering cardiac pacing impulses under the control of control and timing system 102 . Delivery of pacing pulses to two or more heart chambers is controlled in part by the selection of programmable pacing intervals, which can include atrial-atrial (A-A), atrial-ventricular (A-V), and ventricular-ventricular (V-V) intervals.
[0034] Physiologic input signal processing circuit 108 is provided for receiving cardiac electrogram (EGM) signals for determining a patient's heart rhythm. Physiologic input signal processing circuit 108 additionally can receive signals related to intra- or inter-atrial delay and processes these signals and provides signal data to control and timing system 102 for further signal analysis and/or storage. For purposes of illustration of the possible uses of the invention, a set of lead connections are depicted for making electrical connections between the therapy delivery system 106 and the input signal processing circuit 108 and sets of pace/sense electrodes located in operative relation to the RA, LA, RV and/or LV.
[0035] Control and timing system 102 controls the delivery of bi-atrial, bi-ventricular, or multi-chamber cardiac pacing pulses at selected intervals intended to improve heart chamber synchrony. The initial delivery of pacing pulses by IPG 14 may be programmed to nominal settings or provided according to programmable pacing intervals, such as programmable conduction delay window times as generally disclosed in U.S. Pat. No. 6,070,101 issued to Struble et al., incorporated herein by reference in its entirety, or programmable coupling intervals as generally disclosed in above-cited U.S. Pat. No. 6,473,645 issued to Levine. Selection of the programmable pacing intervals while a patient is ambulatory is preferably based on intra-, inter-atrial delay and/or based upon clinical evidence of ventricular filling characteristics or dimensions of ventricular chamber (i.e., chamber volume) as described herein.
[0036] The therapy delivery system 106 can optionally be configured to include circuitry for delivering cardioversion/defibrillation therapy in addition to cardiac pacing pulses for controlling a patient's heart rhythm. Accordingly, as previously mentioned medical electrical leads in communication with the patient's heart can also advantageously include high-voltage cardioversion or defibrillation shock electrodes.
[0037] A battery 136 provides a source of electrical energy to power components and circuitry of IPG 14 and provide electrical stimulation energy for delivering electrical impulses to the heart. The typical energy source is a high energy density, low voltage battery 136 coupled with a power supply/POR circuit 126 having power-on-reset (POR) capability. The power supply/POR circuit 126 provides one or more low voltage power (Vlo), the POR signal, one or more reference voltage (VREF) sources, current sources, an elective replacement indicator (ERI) signal, and, in the case of a cardioversion/defibrillator capabilities, high voltage power (Vhi) to the therapy delivery system 106 . Not all of the conventional interconnections of these voltages and signals are shown in FIG. 2 .
[0038] Current electronic multi-chamber pacemaker circuitry typically employs clocked CMOS digital logic ICs that require a clock signal CLK provided by a piezoelectric crystal 132 and system clock 122 coupled thereto as well as discrete components, e.g., inductors, capacitors, transformers, high voltage protection diodes, and the like that are mounted with the ICs to one or more substrate or printed circuit board. In FIG. 2 , each CLK signal generated by system clock 122 is routed to all applicable clocked logic via a clock tree. The system clock 122 provides one or more fixed frequency CLK signal that is independent of the battery voltage over an operating battery voltage range for system timing and control functions and in formatting uplink telemetry signal transmissions in the telemetry I/O circuit 124 .
[0039] The RAM registers included in microprocessor-based control and timing system 102 may be used for storing data compiled from sensed EGM signals, wall motion signals, and/or relating to device operating history or other sensed physiologic parameters for uplink telemetry transmission upon receipt of a retrieval or interrogation instruction via a downlink telemetry transmission. Criteria for triggering data storage can be programmed via down linked instructions and parameter values. Physiologic data, including septal wall motion data, may be stored on a triggered or periodic basis or by detection logic within the physiologic input signal processing circuit 108 . In some cases, the IPG 14 includes a magnetic field sensitive switch 130 that closes in response to a magnetic field, and the closure causes a magnetic switch circuit 120 to issue a switch closed (SC) signal to control and timing system 102 which responds in a magnet mode. For example, the patient may be provided with a magnet 116 that can be applied over the subcutaneously implanted IPG 14 to close switch 130 and prompt the control and timing system to deliver a therapy and/or store physiologic data. Event related data, e.g., the date and time and current pacing parameters, may be stored along with the stored physiologic data for uplink telemetry in a later interrogation session.
[0040] Uplink and downlink telemetry capabilities are provided to enable communication with either a remotely located external medical device or a more proximal medical device on or in the patient's body. Stored EGM data (and data derived therefrom), as well as real-time generated physiologic data and non-physiologic data can be transmitted by uplink RF telemetry from the IPG 14 to the external programmer or other remote medical device 26 in response to a downlink telemetered interrogation command. As such, an antenna 128 is connected to radio frequency (RF) transceiver circuit 124 for the purposes of uplink/downlink telemetry operations. Telemetering both analog and digital data between antenna 128 and an external device 26 , also equipped with an antenna 118 , may be accomplished using numerous types of telemetry systems known in the art for use in implantable devices.
[0041] The physiologic input signal processing circuit 108 includes at least one electrical signal amplifier circuit for amplifying, processing and in some cases detecting sensed events from characteristics of the electrical sense signal or sensor output signal. The physiologic input signal processing circuit 108 may thus include a plurality of cardiac signal sense channels for sensing and processing cardiac signals from sense electrodes located in relation to a heart chamber. Each such channel typically includes a sense amplifier circuit for detecting specific cardiac events and an EGM amplifier circuit for providing an EGM signal to the control and timing system 102 for sampling, digitizing and storing or transmitting in an uplink transmission. Atrial and ventricular sense amplifiers include signal processing stages for detecting the occurrence of P-waves and R-waves, respectively, and providing atrial sense or ventricular sense event signals to the control and timing system 102 . Timing and control system 102 responds in accordance with its particular operating system to deliver or modify a pacing therapy, if appropriate, or to accumulate data for uplink telemetry transmission in a variety of ways known in the art. Thus the need for pacing pulse delivery is determined based on EGM signal input according to the particular operating mode in effect. The operative A-V intervals for pacing pulse delivery can vary based on heart rate, sensed level activity (e.g., via a piezoelectric crystal, accelerometer, etc.), detected inter-atrial delay, filling characteristics and/or measured ventricular chamber volume.
[0042] FIG. 3 is a flow chart providing an overview of a method for optimizing cardiac pacing intervals according to the present invention. Method 200 begins at step 205 , wherein LVEDV, LVESV, filling characteristics and/or measured intra-atrial delay (e.g., measured via ECG, or electrogram—EGM, or using Doppler ultrasound, or mechanically monitored or detected). As is known in the art, these values are readily obtained using known echocardiographic techniques. At step 210 , an optimal A-V interval is determined based upon the values obtained in step 205 . Depending on the dual chamber or multichamber pacing system being used, a right A-V interval or a left A-V interval or both may be determined. For the embodiment shown in FIG. 1 , an optimal RA to LV interval is determined. However, in other embodiments, the left atrial-left ventricular interval is optimized based on the value obtained in step 205 to ensure optimal filling of the LV. At step 215 , the A-V interval is automatically adjusted to the optimal A-V interval determined at step 210 .
[0043] Optionally, at step 220 the optimal V-V interval is determined for bi-ventricular or atrio-biventricular pacing modes. A method for optimizing the V-V interval can be used that relies upon accelerometer sensors coupled to the LV or the ventricular septum and the like (as described and depicted in the co-pending applications incorporated hereinabove). At optional step 225 , the V-V interval is automatically adjusted to the optimal V-V interval determined at step 220 . After adjusting the V-V interval, an optional step 230 may be performed to re-optimize the A-V interval. Verification of the provisionally determined optimal A-V interval is made by re-determining the optimal A-V interval during biventricular pacing at the newly optimized V-V interval. The A-V interval may be re-adjusted accordingly if a different A-V interval is identified as being optimal during pacing at the optimal V-V interval.
[0044] FIG. 4 is a flow chart summarizing steps included in a method for determining an optimal A-V interval for use in method 200 of FIG. 3 . Method 300 begins at step 305 by setting the A-V interval to a desired nominal value. For example, a nominal A-V interval setting of 100 ms may be used. At step 310 , any intra-atrial delay present is monitored and characterized using, for example, non-invasive echocardiographic equipment, surface-based ECG equipment and/or internal electrogram (EGM) monitoring techniques. For example, in the embodiment depicted at FIG. 4 , inter-atrial delay is declared present if a P-wave duration exceeds about 100 ms or the RA activates more than 60 ms prior to the LA activation. However, other values and techniques may be used. As depicted in FIG. 4 , in the event that intertribal delay is deemed present, then at step 315 the A-V interval is incremented upward (as depicted 40 ms is added to the A-V interval). If no inter-atrial delay is present then at step 320 no change to the A-V interval occurs and the method proceeds to step 325 . At step 325 , an LVEDV value is obtained (e.g., measured or otherwise determined). If the LVEDV value exceeds a threshold value (i.e., 275 ml as shown in FIG. 4 ), then at step 330 the A-V interval is decremented by an amount (e.g., 40 ms). If the LVEDV value does not exceed the threshold value, then at step 335 no change is made. Also, a different or additional initial A-V interval may be used than the 100 ms value described above. In addition, the method depicted in FIG. 4 may be iteratively applied, periodically or otherwise anytime that one or more of LVEDV, LVESV and/or inter-atrial delay information is available for a given patient. Furthermore, one or more mechanical sensors may be used to confirm that physiologically appropriate A-V intervals are being used.
[0045] In a patient with intact atrioventricular conduction, the method depicted and described with respect to FIG. 4 may include patient's intrinsic A-V interval as a factor in setting the initial A-V interval (at step 305 ). This may be very useful in the event that the patient is receiving so-called fusion pacing based on intrinsic atrial activation. In order to allow intrinsic A-V conduction, the A-V interval is set at a maximum setting or a setting longer than the intrinsic A-V conduction time. The intrinsic A-V conduction time may be determined by measuring the interval from an atrial pacing pulse to a subsequently sensed R-wave. Remaining test A-V intervals may be applied at decreasing increments from the intrinsic A-V interval. Alternatively, test A-V intervals may be applied randomly ranging from 0 ms to the intrinsic A-V interval. If atrioventricular conduction is not intact, a set of test A-V intervals may be selected over a predefined range, for example a range from 0 ms to on the order of 250 ms.
[0046] While not depicted, sustaining a stable heart rate during the data acquisition interval is performed may be beneficial. Heart rate instability, such as the presence of ectopic heart beats or other irregularities, can produce anomalous mechanical (motion) data. As such, the heart rate preferably stays within a specified range. In one embodiment, heart rate stability may be verified by determining the average and standard deviation of the cardiac cycle length during the data acquisition period. The cardiac cycle length may be determined as the interval between consecutive ventricular events including ventricular pacing pulses and any sensed R-waves. If the average cardiac cycle length or its standard deviation falls outside a predefined range, the data is considered unreliable.
[0047] When method 300 is executed by an external pacing system, the obtained data relating to LVEDV, LVESV and/or inter-atrial (electrical or mechanical) delays may be displayed in real-time or stored and presented following an optimization procedure. When method 300 for identifying an optimal A-V interval is executed by an implanted device, the obtained data may be stored for later uplinking to an external device for display and review by a physician.
[0048] The optional steps 220 , 225 , 230 of FIG. 3 for determining an optimal V-V interval are now briefly described. The optimal A-V interval is programmed to an optimal setting determined according to method 300 of FIG. 4 . The V-V interval is set to a test interval and a range of test intervals are predefined and may be delivered in a random, generally increasing, or generally decreasing fashion. A range of test intervals may include intervals that result in the right ventricle being paced prior to the left ventricle and intervals that result in the left ventricle being paced prior to the right ventricle. A set of exemplary test intervals includes right ventricular pacing 20 ms and 40 ms prior to left ventricular pacing, simultaneous left and right ventricular pacing (a V-V interval of 0 ms), and left ventricular pacing 20 ms and 40 ms prior to the right ventricle. After each of a plurality of test V-V intervals are applied, the optimal V-V interval is identified as having the least amount of extraneous or dysschronous motion. When the V-V interval is determined using an external pacing system in a clinic having echocardiographic imaging and measurement equipment, ventricular volumes, ventricular wall motion and/or septal wall motion data may be displayed in real-time or stored and presented during optimization procedures. When identifying an optimal V-V interval using an implanted device, the volume data and/or wall motion data may be stored for later uplinking to an external device for display and review by a physician. After identifying the optimal V-V interval, the V-V interval setting may be automatically adjusted or programmed.
[0049] When the methods of the present invention are implemented in an implantable device, stored data available through uplink telemetry to an external device can be displayed and/or reviewed by a physician. When such methods are implemented in an external device, a display of cardiac function data may be updated periodically an intra- or inter-atrial delay characteristic changes.
[0050] Thus, a method and apparatus have been described for optimizing a cardiac therapy. The methods described herein may advantageously be applied in numerous cardiac monitoring or therapy modalities including chronic or acute applications associated with implantable or external devices. In addition, certain of the methods and apparatus operated according to the present invention can be operated using computer processors operating pursuant to instructions stored on a computer readable medium. Accordingly, all diverse types of computer readable medium and other substrates capable of producing control signals for operating structure according to the invention are included with the scope of the invention. | Determining an optimal atrioventricular interval is of interest for proper delivery of cardiac resynchronization therapy. Although device optimization is gradually and more frequently being performed through a referral process with which the patient undergoes an echocardiographic optimization, the decision of whether to optimize or not is still generally reserved for the implanting physician. Recent abstracts have suggested a formulaic approach for setting A-V interval based on intrinsic electrical sensing, that may possess considerable appeal to clinicians versus a patient average nominal A-V setting of 100 ms. The present invention presents a methods of setting nominal device settings based on entering patient cardiac demographics to determine what A-V setting may be appropriate. The data is based on retrospective analysis of the MIRACLE trial to determine what major factors determined baseline A-V settings. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
This is a division of application Ser. No. 829,755 Filed Sept. 1, 1977, now U.S. Pat. No. 4,098,889.
BACKGROUND OF THE INVENTION
Adenosine diphosphate, hereafter called ADP, is a principal factor in the aggregation of blood platelets. Platelet aggregation in the blood stream of a mammal can lead to the formation of a thrombus. Agents which interfere with ADP-induced platelet aggregation are of use as antithrombotic drugs.
SUMMARY OF THE INVENTION
The present invention relates to novel 2-(aminoalkylthio)-N,N'-p-phenylenebissulfonamides, novel intermediates, pharmaceutical compositions, and methods of use for the inhibition of ADP-induced platelet aggregation. The compounds may be represented by the general formula ##STR1## wherein n represents the integer 1, 2, or 3; R represents an alkyl having from 1 to about 3 carbon atoms or phenyl; and R' represents an alkyl having from 1 to about 4 carbon atoms or the two R' groups taken together with the adjacent nitrogen represent a 6-membered heterocyclic ring, as for example piperidinyl, and which may optionally contain an oxygen in the 4-position of the ring whereby morpholinyl residue is formed.
Compounds represented by the above general formula have been found to be effective in the inhibition of blood platelet aggregation and are useful as antithrombotic drugs in mammals.
The invention also includes the pharmaceutically-acceptable salts of the 2-(aminoalkylthio)-N,N'-p-phenylbissulfonamides described herein. As used in the specification and claims, the term "pharmaceutically-acceptable salts" refers to non-toxic acid addition salts of the compounds, the anions of which are relatively innocuous to animals at dosages consistent with good platelet aggregation inhibition so that the beneficial effects of the free base are not vitiated by the side effects ascribable to the anions. Pharmaceutically-acceptable salts include those derived from mineral acids such as hydrochloric and sulfuric acids and from organic acids such as lactic, maleic, succinic, fumaric, glutaric, citric, malic, p-toluenesulfonic, methanesulfonic and tartaric acids, and the like.
In general, the compounds of the present invention may be administered in daily dosages of from about 5.6 micromoles to about 400 micromoles of active ingredient per kilogram of body weight as platelet aggregation inhibiting agents. The compounds are administered internally to a mammal either orally or parenterally by subcutaneous, intravenous or intraperitoneal injection or the like, or by implantation or the like, oral administration being preferred. The effective blood platelet aggregation inhibiting amount of the compounds of the invention to be administered internally to a mammal, that is the amount which is effective to substantially inhibit the aggregation of blood platelets, can vary depending upon such factors as the animal treated, the particular compound administered, the period of administration, and the method of administration.
DETAILED DESCRIPTION OF THE INVENTION
Compounds falling within the scope of the present invention may be prepared using one of two methods. The first method is illustrated in Example 1 below. In general, compounds are synthesized by this method through the 1,4-addition of an aminoalkylthiol to a quinoneimide. In situations where the simple 1,4-addition is unsatisfactory due to competing side reactions, the second method as illustrated in Examples 2 and 3 may be used. In the second method, a 2-xanthyl-N,N'-p-phenylenebissulfonamide is saponified to form a 2-mercapto-N,N'-p-phenylenebissulfonamide. The mercaptan is then alkylated by a selected aminoalkylhalide. The general reaction sequence may be represented as follows: ##STR2## wherein X represents a halide and R, R', and n are as defined above.
In forming the compositions of the invention, the active ingredient is incorporated in a pharmaceutical carrier. The term "pharmaceutical carrier" refers to pharmaceutical excipients and includes nutritive compositions such as a solid or liquid foodstuff. In the present specification and claims, "pharmaceutical excipient" refers to known pharmaceutical excipients which are substantially non-toxic and non-sensitizing at dosages consistent with good platelet aggregation inhibiting activity. A preferred pharmaceutical carrier is a surface active dispersing agent.
Suitable solid pharmaceutical carriers which can be employed for formulating the compositions of the invention include starch, lactose, glucose, sucrose, gelatin, microcrystalline cellulose, powdered licorice, powdered tragacanth, malt, rice flour, silica gel, magesium stearate, magnesium carbonate, hydroxypropyl methyl cellulose, chalk and the like, and compatible mixtures thereof. In the preparation of solid compositions, the active ingredient can be triturated with a solid pharmaceutical carrier or mixtures thereof, or otherwise mechanically milled to obtain a uniform mixture. The mixtures can be compressed into tablets or filled into capsules by known procedures, or they can be employed as powders or the like. The solid compositions generally contain from about 0.02 to about 90, inclusive, percent by weight of the active ingredient.
Among the liquid pharmaceutical carriers which can be utilized are ethyl alcohol, propylene glycol, polyethylene glycols, peanut oil, corn oil, water, saline solution, glycerine and water mixtures, glucose syrup, syrup of acacia, mucilage of tragacanth and the like, and compatible mixtures thereof.
The compositions can also contain the active ingredient in admixture with surface-active dispersing agents and, optionally, an inert carrier. Suitable surface-active dispersing agents include natural phosphatides such as lecithin, natural gums such as gum acacia and gum tragacanth, condensation products of ethylene oxide with fatty acids, such as polyoxyethylene stearate, condensation products of ethylene oxide with fatty alcohols such as heptadecaethyleneoxycetanol and esters or partial esters of fatty acids with a hexitol or hexitol anhydride, and their condensation products with ethylene oxide, such as sorbitan monooleate, polyoxyethylene sorbitan monooleate and polyoxyethylene sorbitan monooleate. Such compositions can be in the form of emulsions, suspensions or dispersible powders or granules, and the compositions containing surface-active dispersing agents can also be in the form of tablets, capsules, or the like.
The pharmaceutical compositions described above can also contain, in addition, sweetening agents such as sugar, saccharin or the like, flavoring agents such as carmel, preservatives such as ethyl p-hydroxybenzoate, antioxidants such as ascorbic acid and suitable coloring materials.
The 2-(aminoalkylthio)-N,N'-p-phenylenebissulfonamide compounds can also be incorporated in a foodstuff such as, for example, butter, margarine, edible oils and the like. The active compounds can also be prepared in the form of a nutritive composition in which the active ingredient is mixed with vitamins, fats, proteins or carbohydrates and the like, or mixtures thereof. Such compositions can be prepared in liquid form such as emulsions or suspensions, as well as in solid form. The nutritive compositions are adapted to be administered as the total diet. The nutritive compositions preferably contain from 0.02 to about 2 percent of the active ingredient when administered as the total diet. The compositions can contain higher concentrations of the active ingredient when administered as a supplement.
The active ingredients can also be formulated as concentrated compositions which are adapted to be diluted by admixture with liquid or solid foodstuffs. The concentrated compositions are prepared by mechanically milling or otherwise mixing the active ingredient with an inert carrier such as silica gel, soluble casein, starch or the like, or mixtures thereof. The concentrated compositions can also include additional ingredients such as vitamins, preservatives, antioxidants and flavoring agents. Such compositions contain from 5 to about 90 percent of active ingredient.
The following examples serve to further illustrate the present invention but are not to be construed as a limitation thereon.
EXAMPLE 1
Preparation of 2-(2-(Diethylamino)ethylthio)-N,N'-p-phenylenebismethanesulfonamide Hydrochloride
A solution containing 13.1 grams (0.05 mole) of p-quinonebismethanesulfonimide in 650 ml of acetone was treated with 8.5 grams (0.05 mole) of 2-(diethylamino)ethanethiol hydrochloride, two drops of triethylamine and one milliliter of water under stirring at a temperature of 45°C. The reaction mixture was allowed to stand at ambient temperature for 65 hours after which the solvent was removed by evaporation in vacuo. The crude product identified in the title remained as a gray solid. Two recrystallizations from nitromethane yielded while crystals of the title compound with a melting pint of 176°-176.5°C.
Elemental analysis showed carbon 39.1%, hydrogen 6.03% and nitrogen 9.87% as compared to calculated values of carbon 38.92%, hydrogen 6.07% and nitrogen 9.73%.
Other compounds falling within the scope of the present invention were also prepared using the simple 1,4 -addition of an aminoalkylthiol to a quinoneimide as illustrated in Example 1. These compounds were as follows:
2-(2-(4-Morpholinyl)ethylthio)-N,N'-p-phenylenebismethanesulfonamide, m.p. 188°-189° C.
2-(2-isopropylamino)ethylthio)-N,N'-p-phenylenebismethanesulfonamide, m.p. 73.5°-75.5° C.
2-(2-(dimethylamino)ethylthio)-N,N'-p-phenylenebismethanesulfonamide, m.p. 162.5°-163.5° C.
Free bases as prepared above may be converted to the desired pharmaceutically-acceptable salt by simple acidification using a preselected acid as described above.
EXAMPLE 2
Preparation of 2-(2-(Diethylamino)ethylthio)-N,N'-p-phenylenebisbenzenesulfonamide Hydrochloride
A solution containing 30.0 grams (0.06 mole) of 2-xanthyl-N,N'-p-phenylenebisbenzenesulfonamide and 250 ml of 10% aqueous sodium hydroxide was heated on a steam plate for about two and one half hours. The reaction mixture was cooled and acidified with 6N hydrochloric acid. The white precipitate that formed was collected on a filter and recrystallized wet from glacial acetic acid to give a pale yellow solid. The intermediate product, 2-mercapto-N,N'-p-phenylenebisbenzenesulfonamide, was recrystallized a second time from glacial acetic acid. The melting point was found to be 179.5°-181.5°C. Elemental analysis found carbon 51.4%, hydrogen 3.89%, and nitrogen 6.89% compared to calculated values of carbon 51.41%, hydrogen 3.84%, and nitrogen 6.66%.
A solution was prepared containing 4.21 grams (0.01 mole) of the mercaptan intermediate prepared above in 150 ml of absolute alcohol. While the resulting solution was stirred at 55°C., 1.50 grams (0.01 moles) of 2-(diethylamino)ethyl chloride was added. Following this addition, the reaction vessel was removed from the hotplate and with continued stirring was allowed to cool at ambient temperature over a period of about 30 minutes. The reaction mixture was cooled to about 5° to 10°C. in an ice bath. The title compound formed as a white crystalline solid and was filtered off, then dried. The product had a melting point of 188.5°-190° C.
Elemental analysis found carbon 52.09%, hydrogen 5.41% and nitrogen 7.61% as compared to calculated values of carbon 51.82% hydrogen 5.43% and nitrogen 7.56%.
EXAMPLE 3
Preparation of 2-(2-(1-Piperidinyl)ethylthio)-N,N'-p-phenylenebismethanesulfonamide Hydrochloride
Potassium ethyl xanthate (19.3 grams, 0.120 mole) was added at room temperature to a stirred suspension of 26.2 grams (0.10 mole) of p-quinonedimethanesulfonimide in 500 ml of glacial acetic acid. After about ten minutes, the yellow color disappeared and the 2-xanthyl-N,N'-p-phenylenebismethanesulfonamide precipitated as a white solid. This was collected on a filter, washed with glacial acetic acid and then with ether, and finally dried in vacuo over potassium hydroxide. The xanthyl-intermediate was recrystallized from ethanol. Elemental analysis found carbon 34.2%, hydrogen 4.21% and nitrogen 7.12% as compared to calculated values of carbon 34.45%, hydrogen 4.20% and nitrogen 7.29%. The melting point was 174.5° C.
A solution of 68.6 g (0.178 mole) of 2-xanthyl-N,N'-p-phenylenebismethanesulfonamide in 430 ml of 10% aqueous sodium hydroxide was heated on the steam plate at 90°-95°C. for 50 minutes, poured into ice water and acidified with 6 N hydrochloric acid. The resulting white precipitate was dissolved in hot ethanol, and the solution treated with decolorizing charcoal. The hot mixture was filtered to remove the charcoal and the filtrate was allowed to cool, giving 46.0 g of the crude intermediate as a white solid, m.p. 169°-175° C. Recrystallization of the crude substance from water gave the pure intermediate 2-mercapto-N,N'-p-phenylenebismethanesulfonamide as a very pale yellow, crystalline solid, m.p. 174°-176° C.
Elemental analysis found carbon 32.4%, hydrogen 4.04% and nitrogen 9.55% as compared to calculated values of carbon 32.42%, hydrogen 4.08% and nitrogen 9.45%.
To a solution containing 8.9 g (0.030 mole) of 2-mercapto-N,N'-p-phenylenebismethanesulfonamide dissolved in 500 ml of ethanol at 60° C. was added 4.7 g (0.032 mole) of 2-(1-piperidinyl)ethyl chloride with stirring. The reaction flask was then removed from the heat, and the mixture was allowed to cool to room temperature. At the end of a period of 15 hours the precipitated white solid product (8.9 g) was collected on a filter and dried. Recrystallization from a mixture of nitromethane and dimethylformamide gave the title compound as white crystals, m.p. 218°-218.5° C. dec.
Elemental analysis found carbon 40.7%, hydrogen 5.86% and nitrogen 9.62% as compared to calculated values of carbon 40.57%, hydrogen 5.90% and nitrogen 9.46%.
EXAMPLE 4
Measurement of platelet aggregation in vivo was carried out using the technique described by Broersma et al., Thomb. Diath. Haemorrhag. 29, 201 (1973). Such determinations are based upon the measurement of the blood pressure proximal to a filter with 53 micron openings through which arterial blood flows. Platelet aggregation partially obstructs the filter with time causing a change in the pressure which is proportional to the degree of platelet aggregation (thrombosis).
Fasted male beagle dogs were anesthetized with sodium pentobarbital (35 mg/kg), heparinized (16.5 μ/kg, intravenous) and tested for platelet function using aggregometry. Compounds were administered orally in 0.5% Methocel.sup.(R) (Dow) solutions having the pH adjusted to about 7. Thrombus formation was observed using the filter occlusion technique outlined above. Platelet count, hemocrit, blood pressure, and heart rate were also measured.
Using the above techniques, the compound 2-(2-(dimethylamino)ethylthio)-N,N'-p-phenylenebismethanesulfonamide was found to reduce ADP-induced blood platelet aggregation by 60% in the dog at a dosage of 80 mg/kg of body weight. At the same dosage level, the compound 2-(2-(morpholinyl)ethylthio)-N,N'-p-phenylenebismethanesulfonamide hydrochloride reduced blood platelet aggregation by 43%. The compound 2-(2 -(morpholinyl)ethylthio)-N,N'-p-phenylenebismethanesulfonamide reduced ADP-induced platelet aggregation by 42% at 40 mg/kg. The preferred compound was 2-(2-(diethylamino)ethylthio)-N,N'-p-phenylenebismethanesulfonamide hydrochloride which was found to reduce ADP-induced platelet aggregation by 45% at 20 mg/kg. The same compound was found to completely block collagen-induced platelet aggregation at 40 mg/kg.
The other compounds falling within the scope of the invention while generally less active than the preferred embodiments described above also displayed significant ADP-induced platelet aggregation inhibition. | Novel antithrombotic 2-(aminoalkylthio)-N,N'-p-phenylenebissulfonamides, a method for inhibiting blood platelet aggregation, and pharmaceutical compositions. | 2 |
This application is a divisional of application Ser. No. 10/061,203, filed on Feb. 4, 2002, now U.S. Pat. No. 6,664,337 which is a divisional under 37 C.F.R. §1.53(b) of prior application Ser. No. 09/254,510 filed on Mar. 9, 1999, now abandoned, for which priority is claimed under 35 U.S.C. §120. Application Ser. No. 10/061,203 is the national phase of PCT International Application No. PCT/JP97/03098 filed on Sep. 4, 1997 under 35 U.S.C. §371. The entire contents of each of the above-identified applications are hereby incorporated by reference. This application also claims priority of Application No. 237720/1996 filed in Japan on Sep. 9, 1996 under 35 U.S.C. §119.
FIELD OF THE INVENTION
The present invention relates to a method for stabilizing a fluorine-containing polymer. In particular, the present invention relates to a method for stabilizing a fluorine-containing polymer by treating a fluorine-containing polymer which has unstable chain ends and/or unstable bonds in the backbones under specific conditions.
PRIOR ART
In the case of, for example, emulsion copolymers of tetrafluoroethylene and hexafluoropropylene, bubbles or voids may be formed from volatile materials in products produced by melt processing. The volatile materials are generated from the unstable chain ends and unstable backbones of the polymers, when heat or shear force is applied to the polymers.
The kinds of unstable chain end groups vary with polymerization methods, and the kinds of polymerization initiators and chain transfer agents. For example, carboxylic acid terminal groups are formed, when a conventional persulfate salt (e.g. ammonium persulfate, potassium persulfate, etc.) is used as a polymerization initiator in emulsion polymerization. It is known that such carboxylic acid terminal groups are the sources for volatile materials in the melt processing. Depending on the conditions in the melt processing, groups such as olefinic groups (—CF═CF 2 ), acid fluoride groups (—COF) and the like are formed at the chain ends. These end groups may cause bubbles or voids in the final products of the polymers.
Backbones which may generate volatile materials may be bonds between comonomers other than tetrafluoroethylene (TFE), as U.S. Pat. No. 4,626,587 describes. In the case of tetrafluoroethylene-hexafluoropropylene copolymers (FEP), the unstable bonds in the backbones are bonds between hexafluoropropylene monomers (HFP). This is confirmed form the fact that, when a gas generated by heating and melting FEP around 400° C. is analyzed, a molar ratio of HFP to TFE in the generated gas is about two times larger than that in the polymers.
U.S. Pat. No. 4,626,587 proposes the removal of unstable chain end groups and unstable bonds in the backbones, which may be the cause of bubbles or voids found in the final products of fluorine-containing polymers, by the application of a shear force with a twin-screw extruder. However, the use of a twin-screw extruder can remove the unstable bonds in the backbones because of the large shear force of the extruder, but hardly stabilizes the unstable end groups because of the too short residence time. In addition, it is very difficult to remove coloring which appears because of the severe melting conditions, and the residues of polymerization initiators or contamination. Thus, additional stabilization treatment such as fluorination with other equipment is necessary after the treatment with the twin-screw extruder. Furthermore, molded articles should be treated at a temperature lower than the melting point of the polymer, when the unstable end groups are stabilized after melt molding, since the shapes of the molded articles should be maintained.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method for effectively removing unstable end groups and unstable bonds in backbones from fluorine-containing polymers and also coloring, in the melt kneading step.
The above object can be achieved by a method for improving the thermal stability of a fluorine-containing polymer comprising melt kneading a melt-processable fluorine-containing polymer with a kneader which has a residence time of at least 10 minutes, a usable volume ratio (usable space in a container/space in a container) of larger than 0.3, and a power factor K of less than 8000, the power factor K being represented by the formula:
K=Pv/μ/n
2
wherein Pv is a power requirement per unit volume (W/m 3 ), μ is a melt viscosity (Pa.s), and n is a rotation speed (rps).
DETAILED DESCRIPTION OF THE INVENTION
A kneader used in the method of the present invention is distinguished from the above twin-screw extruder in that the kneader has a longer residence time than the extruder, that is, the residence time is usually at least 10 minutes, preferably between 10 and 120 minutes, and that the structures (e.g. usable volume ratios, etc.) and the power factors are different between them.
The conventional twin-screw has a usable volume ratio (usable space in a container/space in a container) of 0.3 or less, while a kneader which is preferably used in the present invention, that is, a so-called “surface renewal type kneader” has a usable volume ratio of larger than 0.3, preferable at least 0.5. Herein, a usable space in a container means the space volume of a container in which paddles, a shaft, and the like are equipped, while a space in a container means a space volume of a container not having paddles, a shaft, or the like.
The twin-screw extruder has a power factor K, which is defined by the above formula, in the range between 8,000 and 12,000, while the surface renewal type kneader has a power factor of less than 8,000, often 7,000 or less. The surface renewal type kneader has self-cleaning properties, and high piston flow properties in continuous operation.
Typical examples of the surface renewal type kneaders include HVR, SCR and NEW-SCR (all manufactured by Mitsubishi Heavy Industries, Ltd.), BIBOLACK (manufactured by Sumitomo Heavy Machinery and Industries, Ltd.), HITACHI EYEGLASS-PADDLE POLYIMERIZER and HITACHI GATE-PADDLE POLYMERIZER (manufactured by Hitachi Ltd.), AP-MACHINE and NEW AP-MACHINE (manufactured by LIST), and the like.
Examples of the fluorine-containing polymers which are stabilized by the method of the present invention include melt-processable copolymers comprising at least two monomers selected from the group consisting of tetrafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ethers, ethylene, vinylidene fluoride and chlorotrifluoroethylene; vinylidene fluoride homopolymer; chlorotrifluoroethylene homopolymer; and the like.
The perfluoroalkyl vinyl ethers include a vinyl ether of the formula:
CF 2 ═CFO(CF 2 ) m F
wherein m is an integer of 1 to 6, and
a vinyl ether of the formula:
CF 2 ═CF(O—CF 2 CF(CF 3 )) n OC 3 F 7
wherein n is an integer of 1 to 4.
In particular, when a fluorine-containing polymer, which is treated by the method of the present invention, is a tetrafluoroethylene-hexafluoropropylene copolymer (FEP), it preferably comprises 72 to 96 wt. % of tetrafluoroethylene and 4 to 28 wt. % of hexafluoropropylene. When a fluorine-containing polymer is a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), it preferably comprises 92 to 99 wt. % of tetrafluoroethylene and 1 to 8 wt. % of a perfluoroalkyl vinyl ether. When a fluorine-containing polymer is a tetrafluoroethylene-ethylene copolymer (ETFE), it preferably comprises 74.5 to 89.3 wt. % of tetrafluoroethylene and 10.7 to 25.5 wt. % of ethylene.
These polymers may comprise other monomers in an amount such that the inherent properties of each copolymer do not deteriorate. Examples of the other monomers include hexafluoropropylene (when the fluorine-containing polymer does not comprise hexafluoropropylene), perfluoroalkyl vinyl ethers (when the fluorine-containing polymer does not comprise a perfluoroalkyl vinyl ether), ethylene (when the fluorine-containing polymer does not comprise ethylene), vinylidene fluoride (when the fluorine-containing polymer does not comprise vinylidene fluoride), and chlorotrifluoroethylene (when the fluorine-containing polymer does not comprise chlorotrifluoroethylene).
The melt processable fluorine-containing polymers are preferably prepared by emulsion or suspension polymerization. When the polymers are FEP, PFA, and copolymers of tetrafluoroethylene, hexafluoropropylene and a perfluoroalkyl vinyl ether, they have a melt viscosity in the range between 0.1 and 100 kpa.s at 372° C.
The method of the present invention is carried out preferably at a temperature in the range between 200 and 450° C.
The method of the present invention requires a residence time of at least 10 minutes to achieve the desired effects. When the residence time is less than 10 minutes, it is difficult to obtain a fluorine-containing polymer having sufficient heat stability and no coloring.
The kneader used in the method of the present invention may be a batch apparatus or a continuous apparatus, and preferably has good self-cleaning properties, and good piston flow properties in continuous operation. When these properties of the kneader are insufficient, it may take a long time for obtaining all the charged raw materials in the desired states.
The polymer is preferably discharged from the kneader in the continuous operation with a single-screw extruder which has a vent for removing gasses which are dissolved in the molten polymer.
For effectively removing the unstable end groups and unstable bonds in the backbones from the fluorine-containing polymers and improving the heat stability of the polymer, one or more of the following additional procedures may be combined with the above described fundamental conditions of the method of the present invention:
a) Supplying pure fluorine gas, or fluorine gas which is diluted to a suitable concentration, in a sufficient amount for removing all the unstable end groups into a kneader;
b) Supplying water or steam in a sufficient amount for removing all the unstable end groups into a kneader;
c) Adding salts or bases comprising alkali metals or alkaline earth metals, ammonia, amines or their salts, or alcohols to the fluorine-containing polymers, and then charging the polymer into a kneader;
d) Adding salts or bases comprising alkali metals or alkaline earth metals, ammonia, amines or their salts, or alcohols to the fluorine-containing polymers, prior to or during any step of the method of the present invention;
e) Allowing the fluorine-containing polymers in contact with inert gas for a sufficient time prior to the charging of the polymer in a kneader for removing substantially all the absorbed or adsorbed oxygen in the polymer, and then supplying the polymer in a kneader.
The treatment of the present invention can remove almost all the unstable end groups and unstable bonds in the backbones, and convert the unstable end groups to stable perfluoromethyl end groups (—CF 3 ), difluorohydride end groups (—CF 2 H), acid amide end groups (—CONH 2 ) and methyl ester end groups (—COOCH 3 ).
The amount of unstable end groups and stable end groups can be quantitatively measured by infrared spectrometry. Such a measuring method is disclosed in U.S. Pat. Nos. 3,085,083 and 4,675,380, the disclosures of which are hereby incorporated by reference, and JP-A-4-20507. The number of end groups can be measured as the number per 10 6 carbon atoms by this measuring method.
The amount of materials which volatilize during the melt processing of the polymers can be assayed by the measurement of a volatile index, that is, a VI value, which is known. The measuring method of a VI value will be explained below.
Ten grams of a polymer sample is charged in a heat resistant container, and placed in a glass vessel which is connected with a vacuum line.
The vessel is evacuated to a reduced pressure of 2 mmHg or less, and inserted in a high temperature block kept at 380° C. to achieve thermal equilibrium.
The pressure change is recorded every ten minutes over 60 minutes, and a VI value is calculated in accordance with the following formula:
VI =( P 40 −P 0 )× V/ 10/ W
wherein P 0 and P 40 are a pressure prior to the insertion in the high temperature block and a pressure after 40 minutes from the insertion in the high temperature block, respectively, V is the volume (ml) of the vessel, and W is the weight (g) of the sample.
The volatile index is preferably less than 25. When the volatile index is larger than 25, bubbles or voids, which cause troubles in the melt processing, may form.
The degree of coloring depends on the severity of melting conditions, residues of polymerization initiators, and presence of contamination. The main cause for the coloration is supposed to be carbon atoms which appear in the polymers at a temperature of 200° C. or higher. This supposition may be reasonable, since the degree of coloration has substantially perfect correlation with the number of unpaired electrons on the carbon atoms of the sample polymers, when the number of unpaired electrons on the carbon atoms of the sample polymers having different degrees of coloring is measured by ESR.
The polymers have substantially no coloring, when the number of unpaired electrons on the carbon atoms is between 0 and 1×10 14 spins/g, preferably 5×10 13 spins/g or less, in terms of a spin density, which is measured by ESR at 77K. The method of the present invention can easily achieve such a spin density level.
The method of the present invention can effectively remove the unstable end groups and unstable bonds in the backbone during melt kneading, and provide colorless fluorine-containing polymers while avoiding the complicated conventional method which comprises removing the unstable bonds in the backbones with a twin-screw extruder, and then removing unstable end groups with other equipment, as disclosed in U.S. Pat. No. 4,626,587.
Now, the present invention will be illustrated by the following examples.
EXAMPLE 1
A FEP powder, which had been prepared by emulsion polymerization using ammonium persulfate (APS), had a melt viscosity of 2.8 kPa.s, and contained 12 mole % of HFP, was treated as follows, and then the kinds and numbers of end groups of the obtained FEP, and a volatile index were measured.
The above FEP powder (1 kg) was charged in a surface renewal type kneader having an internal volume of 1 liter, a usable volume ratio of 0.82 and a power factor K of 225 (“BIBOLACK” manufactured by Sumitomo Heavy Machinery and Industries, Ltd.), and kneaded for 40 minutes at 380° C. and 50 rpm, while passing pure water at a rate of 2.0 g/min. and an air at a rate of 0.3 NL/min.
The obtained polymer was a milk-white one with transparency.
The kinds and amounts of the end groups and the volatile indexes (VI) of the FEP powder before and after the treatment are shown in Table 1. Almost all the unstable end groups were removed, and the volatile index was lower after the treatment.
The amount of unpaired electrons on the carbon atoms of the polymer after the above treatment is shown in Table 1 in terms of a spin density measured by ESR at 77K. The spin density was very low.
Substantially all the unstable end groups were removed, and also the volatile index (VI) was low.
EXAMPLE 2
FEP powder was treated in the same manner as in Example 1 except that the internal air of the kneader was thoroughly replaced with nitrogen gas after the charging of the FEP powder, no water was added during the treatment, and a fluorine gas which was diluted with nitrogen to a concentration of 7.6 mole % was passed at a rate of 0.3 NL/min. in place of air, and the treating period of time was 60 minutes.
After the treatment, the fluorine gas in the internal space of the kneader was thoroughly replaced with nitrogen gas, and then the content was discharged from the kneader. The FEP powder after treatment was milk-white.
The kinds and amounts of the end groups and the volatile indexes (VI) of the FEP powder before and after the treatment are shown in Table 1. Almost all the unstable end groups were removed, and the volatile index was lower after the treatment.
The amount of unpaired electrons on the carbon atoms of the polymer after the above treatment is shown in Table 1 in terms of a spin density measured by ESR at 77K. The spin density was very low.
TABLE 1
Example 1
Example 2
Before
After
Before
After
treatment
treatment
treatment
treatment
End
—COF
0
0
groups
(groups/
—COOH (m)
131
2
131
3
10 6 C.
—COOH (d)
677
5
677
4
atoms
VI
>100
4.2
>100
4.5
Spin density (spins/g)
—
2.7 × 10 13
—
2.2 × 10 13
Comparative Example
The same FEP powder as one used in Examples 1 and 2 was pelletized with a single-screw extruder having a screw diameter of 50 mm and a L/D ratio of 30 at a cylinder temperature of 380° C. The pellets were fluorinated with fluorine gas, which had been diluted with nitrogen gas to a concentration of 7.6 mole %, in an autoclave at 185° C. The volatile index was measured with varying the fluorination time. The results are shown in Table 2.
It is found that the fluorination time of about 8 hours is necessary for achieving a volatile index of 25 or less.
The amount of unpaired electrons on the carbon atoms of the polymer just after the extrusion was as high as 4.5×10 15 spins/g in terms of a spin density measured by ESR at 77K.
TABLE 2
Fluorination time (hrs)
VI
0
48
2
35
3
29
6
26
8
23 | A melt-processable fluorine-containing polymer is melt kneaded with a kneader which has a residence time of at least 10 minutes, a usable volume ratio (usable space in a container/space in a container) of larger than 0.3, and a power factor K of less than 8000, the power factor K being represented by the formula: K=Pv/μ/n 2 in which Pv is a power requirement per unit volume (W/m 3 ), μ is a melt viscosity (Pa.s), and n is a rotation speed (rps), to effectively remove terminal groups and bonds in the backbones, which are unstable during melt kneading, from the melt-processable fluorine-containing polymer, and obtain a colorless fluorine-containing polymer. | 2 |
BACKGROUND OF THE INVENTION
The present invention concerns a device for closing a structure such as, for example, a munitions compartment of a rocket. This device can be ejected upon command, so that the structure is opened at the desired moment.
Current military strategy used to neutralize vital enemy installations such as, for example, landing areas, entails two stages:
in the first stage, a rocket with munitions is either sent above the zone to be neutralized by means of a launching tube or is jettisoned from an aircraft;
in the second stage, the munitions are ejected on command.
Methods for releasing munitions are widely known and shall not be described below. The invention relates to the closing of the compartments by means of devices that can be released upon command.
Such devices exist. A known device consists of a hatch, embrittled in certain places and fixed to the compartment at other places. An outward thrust from the compartment is given at the embrittled portions which break and then go beyond the fuselage of the rocket. The aerodynamic drag coefficient (hereinafter marked Cx) of this rocket is then modified and this difference in Cx causes the hatch to be partially torn away. Since the hatch is only partially torn away, the opening of the compartment is not adequately controlled and there is the risk that pieces of the hatch may hamper the passage of the munitions.
SUMMARY OF THE INVENTION
An object of the present invention is to remove this drawback. The invention concerns an ejectable closing device for a structure, such as a munitions compartment for example, which is not broken but dismantled when it is ejected. The structure is closed by a lid held in position by locking means. A thrust of the locking means, outward from the structure, releases the lid of these locking means and then completely expels the lid preferably by triggering spring devices.
the lid of the device according to the invention being totally expelled, the opening of the structure is perfectly controlled and reproducible.
More precisely, an object of the present invention is an ejectable closing device for a structure, said device comprising:
a lid;
means for outward thrusting from said structure, said device further comprising:
means to lock said lid;
means to transmit said thrust to said locking means, said thrust being capable of releasing said lid from said locking means and, then, of causing the complete expulsion of said lid.
BRIEF DESCRIPTION OF THE DRAWINGS
Specific features and various embodiments of the invention will emerge from the following description, illustrated by the appended figures, of which:
FIG. 1 shows a cross-section of a rocket comprising three devices according to the invention;
FIG. 2 is a partial section of a first embodiment of the device according to the invention before it is ejected;
FIG. 3 is a partial section of the device of FIG. 2 at the start of its ejection;
FIG. 4 is a partial section of the device of FIG. 2 at the end of its ejection;
FIG. 5 is a partial section of a second embodiment of the device according to the invention;
FIG. 6 is a partial section of a third embodiment of the device according to the invention.
In these various figures, the same references refer to the same elements.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description will be made, as an example with reference to an application of the device, according to the invention, to the closing of a rocket compartment containing munitions.
the rocket comprises a cylindrical part 24 in which munitions compartments are located. FIG. 1 shows an example of a configuration of a cylindrical part 24 of this type. The rocket has three compartments 23, for example identical compartments, each containing one piece of munition 21. The compartments 23 are closed by lids 1 located on the edge of the cylindrical part 24, the longitudinal edges of these lids 1 being fixed, according to the invention, by means 22 (the transversal edges of these lids are fitted into the part 24). The cylindrical part 24 has as many means 22 as it has lids 1. Each means 22 holds two different lids 1 and, reciprocally, two opposite longitudinal edges of a given lid 1 are held by two different means 22. hereinafter, the fixing of only one longitudinal edge of a lid 1 by a single unit 22 shall be described.
FIG. 2 shows a section of a first embodiment of the device according to the invention, comprising a lid 1, only one part of which is sketched in the figure, and means 22 which is entirely shown. This figure illustrates the configuration of the device before it is ejected. The edge 8 of the lid 1 is held by the means 22 comprising:
a part 2, called a "key", fitted inside the edge 8 and clamping the external part of this edge 8, thus locking the lid 1;
means to thrust the key 2 and the edge 8 outwards from the structure, said thrusting means comprising an inflatable membrane 3. A part 10 of the membrane 3 is fixed, for example, by bonder to the edge 7 of the compartment 23. This edge 7 has the shape of a cup to the bottom of which the part 10 is bonded;
means for transmitting this thrust, comprising a rigid small bar 4 and a spring leaf 5; the small bar 4 is located between the key 2 and the membrane 3; the spring 5 is compressed between the small bar 4 and the edge 8 of the lid 1 throughout the period between the assembly of the device and the ejection of this same device; the spring is said to be "prestressed" between the small bar 4 and the internal part of the edge 8;
a screw 6 for fixing the key 2 to the small bar 4; this fixing means holds the device in position before it is ejected.
The edge 8 of the lid 1 has a bulge 28 which presses against the edge 7 of the compartment 23. A seal 13 located between the edges 8 and 7 gives imperviousness to the closing of the compartment 3 as it is not desirable for the munitions to get wet or damp.
FIGS. 3 and 4 illustrate the ejection of the device of FIG. 2.
This type of ejection is triggered by the inflation of the membrane 3 which is connected, for example, to a pyrotechnical gas generator, not shown in FIGS. 2 to 4. Techniques for inflating membranes designed to give thrust of any kind are known per se and shall, therefore, not be described herein. In becoming inflated, the membrane 3 exerts a thrust which is radial (with respect to the edge 7 of the compartment 23) and centrifugal 9 (with respect to the cylindrical part 24 of the rocket).
the thrust 9 is exerted on the small bar 4, thus compressing the spring 5 as shown in FIG. 3. The shape of the small bar 4 enables the key 2 to come apart from the edge 8. In FIG. 3 the key 2 has almost become unfixed.
As soon as the key 2 gets unfixed, the spring 5 is released and thus expels the edge 8 of the lid 1 as shown by the arrows 11 in FIG. 4. According to the embodiment described, the seal 13 remains fixed to the edge 8 when this edge is expelled. The membrane 3 continues to get inflated and thrusts the elements 4, 5, 2 and 6 in the direction of the arrow 9. The situation obtained is shown in FIG. 4: the device is dismantled. The rocket is preferably subjected to a rotation on its axis in a way known to those skilled in the art, the resultant centrifugal force making it possible, in particular, to boost the ejection of the above-mentioned elements. The various elements then go beyond the rocket fuselage, thus modifying its Cx. This difference in Cx causes, firstly, the lid 1 and, secondly, the elements 2, 6, 4 and 5 to be torn away. Only the membrane 3 remains at least partially fixed to the edge 7 of the compartment 3, but it in no way hampers the ejection of the munitions.
FIG. 5 shows a section of a second embodiment of the device according to the invention before it is ejected. The second embodiment differs from the first one through the fact that the edge 7 of the compartment 13 has a shoulder 12. The spring 5 is pre-stressed between the small bar 4 (as in the case of FIG. 2) and this shoulder 12 (instead of the edge 8 of the lid 1), thus providing greater releasing force in the spring 5 than is the case in the first embodiment.
The device of FIG. 5 works like that of FIG. 2 except as regards the spring 5. This spring is first compressed by the radial and centrifugal thrust caused by the inflation of the membrane 3 (as in FIG. 3); once the key gets unfixed, the spring 5 is released from the shoulder 12 (unlike in FIG. 3) and expands, pushing on the edge 8 of the lid 1 (as in FIG. 4).
FIG. 6 shows a section of a third embodiment of the device according to the invention before it is ejected. The third embodiment differs from the second one in that it has a monobloc small bar consisting of a rigid part 34 and an elastic part 35 instead of the rigid small bar 4 and the spring leaf 5. The parts 34 and 35 respectively fulfil the same functions as the elements 4 and 5 of FIG. 6. Nevertheless, the elastic part 35, unlike the spring 5 is not at all compressed before the ejection of the device. Consequently, its elasticity is in no risk of being reduced through excessively prolonged prestress, given that military equipment is sometimes stored for long periods. The device of FIG. 6 is therefore more reliable than that of FIG. 5 or that of FIGS. 2, 3 and 4. | Disclosed is a device designed to close a munitions compartment of a rocket and to be ejected just before the munitions so as to open the compartment. This device has a lid locked with a key and an inflatable balloon used to release the lid from the key and to dismantle the device without breaking it, by completely expelling the lid. | 5 |
BACKGROUND
[0001] The present disclosure relates to plating deposition processes and equipment, and more particularly, to a method and masking assembly for selectively depositing a plating on a turbine airfoil while preventing deposition of the plating on a dovetail of the airfoil.
[0002] Gas turbine engines, such as those that power modern commercial and military aircraft, generally include a compressor section to pressurize an airflow, a combustor section to burn hydrocarbon fuel in the presence of the pressurized air, and a turbine section to extract energy from the resultant combustion gases.
[0003] Turbine section blades typically include an airfoil which extends into the hot core gases which result from the combustion of fuel in the upstream combustor section. Because of the high temperatures and corrosive effects of such gases on the airfoil s, standard practice may include application of a protective plating that provide insulation from the high temperatures and corrosive effects.
[0004] A root opposite the airfoil attaches the blade to a rotor disk of the engine and is not in need of protection from the high temperatures and corrosive effects of the hot core gases. The root often has a fir-tree shape that is assembled into a corresponding slot in a rotor disk such that after a prolonged time period, the root may exhibit a fatigue-related phenomenon referred to as fretting. Fretting has been found to be exacerbated by plating. Thus, in order to achieve the desired properties in the various s of the turbine airfoil to maximize service life only the airfoil is plated.
[0005] One method to plate only the airfoil is to segregate the airfoil with a mask that protects the root and platform underside before insertion into the plating solution. An operator manually inserts the airfoil into a mask. Installation may be relatively difficult and time consuming as the operator usually requires two hands and a wood table as leverage to wiggle the airfoil into the mask. As a gas turbine engine may contain upwards of eighty airfoils in one stage and multiple different stages, masking turbine components may be time consuming and expensive.
SUMMARY
[0006] A system to install a component into a mask of a gas turbine engine according to one disclosed non-limiting embodiment of the present disclosure includes a movable base and a drive movable along an axis with respect to said movable base.
[0007] In a further embodiment of the foregoing embodiment, the drive supports an insertion cup. In the alternative or additionally thereto, in the foregoing embodiment the insertion cup includes a semi-spherical. In the alternative or additionally thereto, in the foregoing embodiment the insertion cup is non-metallic.
[0008] In a further embodiment of any of the foregoing embodiments, the drive is a linear motor.
[0009] In a further embodiment of any of the foregoing embodiments, the system includes a lubrication mister directed toward said movable base.
[0010] In a further embodiment of any of the foregoing embodiments, the movable base is movable in an X-direction and Y-direction, said Z-direction defined along said axis.
[0011] In a further embodiment of any of the foregoing embodiments, the movable base includes a mask support movable with respect to a housing.
[0012] In a further embodiment of any of the foregoing embodiments, the movable base includes a mask support spring connected and biased between the housing and the mask support.
[0013] A method of masking a component of a gas turbine engine according to another disclosed non-limiting embodiment of the present disclosure includes pressing a component into a mask supported on a movable base.
[0014] In a further embodiment of the foregoing embodiment, the method includes permitting rotational movement of the movable bases.
[0015] In a further embodiment of any of the foregoing embodiments, the method includes permitting tilting movement of the movable bases.
[0016] In a further embodiment of any of the foregoing embodiments, the method includes pressing the component in a Z-direction and permitting movement of the movable bases in an X-direction and Y-direction.
[0017] In a further embodiment of any of the foregoing embodiments, the method includes spraying the component with a lubricant solution.
[0018] In a further embodiment of any of the foregoing embodiments, the method includes pressing the component with a semi-spherical insertion cup.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Various features will become apparent to those skilled in the art from the following detailed description of the disclosed non-limiting embodiment. The drawings that accompany the detailed description can be briefly described as follows:
[0020] FIG. 1 is a perspective view of a turbine component;
[0021] FIG. 2 is a top perspective view of the turbine component partially inserted into a mask;
[0022] FIG. 3 is a bottom perspective view of the turbine component fully inserted into the mask;
[0023] FIG. 4 is a schematic view of a system to press the turbine component into a mask;
[0024] FIG. 5 is a schematic view of a movable base of the system to press the turbine component into the mask;
[0025] FIG. 6 is an expanded schematic view of a spring bias of the movable base;
[0026] FIG. 7 is a top view of the movable base;
[0027] FIG. 8 is a schematic view of a insertion cup;
[0028] FIG. 9 is a schematic partially disassembled view of the movable base of the system to press the turbine component into the mask; and
[0029] FIG. 10 is a flowchart of the method of masking a turbine component.
DETAILED DESCRIPTION
[0030] FIG. 1 schematically illustrates a turbine component 10 that requires plating of only a thereof The turbine component 10 , for example a turbine rotor blade, includes an airfoil 12 , a platform 14 and a root 16 . The turbine component 10 is manufactured of a high temperature superalloy. It should be understood that not all turbine components as defined herein may be identical to that illustrated, and that other turbine components such as vanes and static structure that require a of the component to be masked will also benefit herefrom.
[0031] The turbine component 10 is plated along the airfoil 12 , as the airfoil 12 is subjected to a core flow of corrosive, oxidative gases that impinge the airfoil 12 at temperatures in excess of 2400 degrees F. (1,315 degrees C.). The root 16 need not be plated and the platform 14 is segregates the airfoil 12 and the root 16 . The root 16 also includes openings 18 to cooling passages to communicate a coolant through the airfoil 12 to thermally combat the core flow. The root 16 may be a fir-tree, dovetail, or other convoluted shapes which is precision machined to fit within a correspondingly shaped slot in a rotor disk assembly (not shown). Because of the precision machining, the addition of even small amounts of plating may adversely affect the tight tolerances in the assembly process. In addition, the plating materials may instigate fretting and thereby undesirably effect the fatigue life of the root 16 .
[0032] With reference to FIG. 2 , the root 16 of the turbine component 10 may be protected from a plating operation by a mask 20 that, in one disclosed non-limiting embodiment, is a resilient material that is generally block-shaped in the disclosed non-limiting embodiment but may be of other shapes and configurations. The mask 20 closely fits onto the airfoil 12 and the platform 14 to shield desired of the turbine component 10 from exposure to the plating materials. That is, the mask 20 includes an internal shape that closely mirrors (and may be an interference fits with) the airfoil 12 and the platform 14 contours ( FIG. 3 ). Since the mask 20 is loaded into a fixture (not shown), the root 16 is segregated and thereby protected from the plating process.
[0033] With reference to FIG. 4 , a system 30 facilitates installation of the turbine component 10 into the mask 20 . The system 30 generally includes a movable base 32 , a drive 34 , an insertion cup 36 , a lubricating mister 38 and a controller 40 . The drive 34 is operable to press the turbine component 10 into the mask 20 . It should be appreciated that alternative or additional subsystems may be provided.
[0034] The movable base 32 includes a housing 42 and a mask support 44 which is resiliently mounted within the housing 42 . The housing 42 may be semi-cylindrical with a cylindrical portion 43 and a radially extending base 45 from which the cylindrical portion 43 extends (see FIG. 5 ). The housing 42 includes a load/unload opening 47 that is generally mimicked by the mask support 44 . In the disclosed non-limiting embodiment, an opening 46 includes a load/unload opening 47 to facilitate loading and unloading of the mask 20 . The opening 46 and the load/unload opening 47 may be of various sizes and orientations so as to facilitate operator interaction with the mask 20 .
[0035] A resilient biasing member 48 ( FIGS. 6 and 7 ) such as a multiple of springs or a bladder resiliently position the mask support 44 within the housing 42 . The mask support 44 is at least partially enclosed by a cover 50 attached to the housing 42 with fasteners 51 to constrain movement of the mask support 44 in the X-direction, Y-direction, and Z-direction.
[0036] The drive 34 in the disclosed non-limiting embodiment is a variable speed linear motor. The insertion cup 36 is mounted to the drive 34 to provide a non-metallic semi-spherical engagement surface for contact with the turbine component 10 . The insertion cup 36 prevent damage to the turbine component 10 and permits some relative movement between the turbine component 10 and the mask 20 as the turbine component 10 “wiggles” into the mask 20 under the linear force applied by the drive 34 . The drive 34 may provide variable speed in that the insertion cup 36 is moved relatively rapidly under control of the controller 40 until contact with the turbine component 10 then reduces speed to carefully drive the turbine component 10 into the mask 20 . The drive 34 generates, in one example, less than approximately 10 pounds of force.
[0037] The lubricating mister 38 is directed toward the mask 20 to selectively apply a mist of a lubricant such as a soap solution to the mask 20 in response to the controller 40 . The lubricating mister 38 facilitates insertion of the turbine component 10 into the mask 20 as the as the turbine component 10 is “wiggled” into the mask 20 under the linear force applied by the drive 34 .
[0038] With reference to FIG. 9 , a multiple of bumpers 52 accommodate unequal movement of the mask support 44 in the direction that the drive 34 presses—the Z-direction. The bumpers 52 may be rubber pucks that deform to accommodate the movement of the mask support 44 . That is, the drive 34 presses along an L axis that is oriented in the Z-direction such that straight-line pressure on the turbine component 10 will result in contact between the mask support 44 and all the bumpers 52 . The complex internal shape of the mask 20 which corresponds to the root 16 , however, results in the linear force applied by the drive 34 to displace the mask support 44 in the X-direction and the Y-direction as the turbine component 10 “wiggles” into the mask 20 as the mask support 44 and thereby the mask 20 moves to accommodate this motion in combination with the insertion cup 36 . The multiple of resilient biasing member 48 resiliently positions the mask support 44 within the housing 42 in the X-direction and the Y-direction while the bumpers accommodate movement in the Z-direction as the turbine component 10 “wiggles” into the mask 20 .
[0039] With reference to FIG. 10 , an operator initially pre-loads the turbine component 10 partially into the mask 20 . That is, the airfoil 12 is placed into the mask 20 which is mounted into the movable base 32 . The drive 34 is then actuated. In response to the controller 40 , the insertion cup 36 is moved relatively rapidly under control of the controller 40 until contact with the turbine component 10 then the controller 40 reduces speed of the drive to carefully drive the turbine component 10 into the mask 20 . Once the turbine component 10 is pressed fully into the mask 20 , the drive 34 retracts in response to the controller 40 and the operator may remove the completed masked component from the movable base 32 . The disclosed process eliminates any potential for ergonomic effect upon the operator, allows for consistent masking, eliminates variation in the masking process. It should be appreciated that the disclosed process is readily applicable to other component insertion which may require some “wiggle”.
[0040] It should be understood that relative positional terms such as “forward,” “aft,” “upper,” “lower,” “above,” “below,” and the like are with reference to the normal operational attitude of the vehicle and should not be considered otherwise limiting.
[0041] It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be understood that although a particular component arrangement is disclosed in the illustrated embodiment, other arrangements will benefit herefrom.
[0042] Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present disclosure.
[0043] The foregoing description is exemplary rather than defined by the limitations within Various non-limiting embodiments are disclosed herein, however, one of ordinary skill in the art would recognize that various modifications and variations in light of the above teachings will fall within the scope of the appended claims. It is therefore to be understood that within the scope of the appended claims, the disclosure may be practiced other than as specifically described. For that reason the appended claims should be studied to determine true scope and content. | A system to install a mask onto a component of a gas turbine engine includes a drive movable along an axis with respect to a movable base. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a 371 of PCT/DE99/03491, filed Oct. 28, 1999.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a motor vehicle with a memory device for storing vehicle operating data. More particularly, the present invention relates to correlating vehicle operating data with distance traveled by the vehicle for diagnostic and maintenance purposes.
2. Description of the Related Art
Vehicles with memories for storing data have become known for example through German Patent Publication No. DE 19639296. For such a vehicle, the energy loss resulting from clutch slippage is added up and stored in a memory device.
This has the disadvantage that the stored data characterize only a snapshot of the condition of the vehicle. During the vehicle's time in a repair shop, for instance, only the current condition can be read from memory.
The purpose of the invention is to provide a vehicle of the above-described kind with improved functionality. Improvements are intended particularly with regard to diagnostics.
SUMMARY OF THE INVENTION
That purpose is accomplished in accordance with the invention with a motor vehicle of the above-described kind by providing a device for determining the distance traveled by the vehicle, and by associating the stored data of the vehicle data with the data of the distance traveled by the vehicle and storing those data together as paired values in a storage unit.
It has proven particularly useful if the vehicle is equipped with at least one driving motor and/or a clutch and/or a transmission. It is also useful if the clutch can be actuated automatically or if, in another embodiment in accordance with the invention, the transmission can be actuated automatically.
Furthermore it can also be beneficial if the clutch is actuated manually or if, in another beneficial embodiment, the transmission is actuated manually.
Is it also advantageous if a device is incorporated, which determines the lost energy resulting from clutch slippage. This can be provided, for example, by determining the energy loss from slippage in an electronic computer unit by integration of the product of the transmittable clutch torque M K and the clutch slippage (N M -N K ), where N M is the engine rotational speed and N K is the transmission input rotational speed.
In doing so it has proven useful to provide a device that determines the engine rotational speed N M or another value representing that value. It is also useful to provide a device that determines the transmission input rotational speed N K , or another value representing that value. Furthermore it is beneficial if a device is provided that determines the torque M K that is transmitted by the clutch, or another value representing that value.
In accordance with the invention it is beneficial if the stored data can be used for the determination of adaptive values. For example, stored information relating to the energy loss or the power loss of the transmission can be used to calculate the wear of the friction linings of a clutch and thereby to adapt the engagement point of the clutch as an adaptive value based on the wear of the clutch linings.
It can also prove beneficial in accordance with the invention to utilize the stored data for failure evaluation and/or failure-warning purposes. For example, storage of the energy loss or the power loss of the transmission can be used to calculate the wear of the friction linings of a clutch and thereby the remaining wear reserve of the clutch, and it can also be used to issue a warning signal that indicates the wear condition when a critical limit value has been reached.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will be further explained with the help of the drawings, in which:
FIG. 1 is a diagrammatic representation of a motor vehicle drive train; and
FIG. 2 is a block diagram of a motor vehicle control unit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 diagrammatically shows a motor vehicle 1 with a drive unit or engine 2 , such as an internal combustion engine or a hybrid drive arrangement with an internal combustion engine and an electric motor. A clutch 3 and a transmission 4 are provided in the drive train and a drive shaft 5 extends from the transmission and which through a differential 6 drives two drive shafts 7 a and 7 b , which, in turn, drive the driven wheels 8 a and 8 b . The clutch 3 is shown as a dry, friction clutch with a pressure plate 10 , a clutch disk 11 , a clutch release bearing 12 , and clutch shift fork 13 , and is assembled with a flywheel. The clutch shift fork 13 is actuated through an actuator 15 including a master cylinder 16 , a pressure-fluid conduit, such as an hydraulic conduit 17 , and a slave cylinder 18 . The actuator 15 is equipped with a relief bore 21 , which is connected with a reservoir 22 for the pressure fluid. The actuator 15 is depicted as a pressure-fluid-actuated actuator, which has an electric motor 19 that actuates the master cylinder piston through a mechanism, so that the torque transmission system can be engaged and disengaged by means of the pressure-fluid conduit 17 and the slave cylinder 18 . The actuator 15 can also be actuated with just an electric motor or just with hydraulics.
Actuator 15 includes a control unit 15 a having control electronics a computer unit for controlling or regulating actuation of the clutch and/or a transmission by means of an actuator. The power electronics and/or the control electronics can be arranged within the actuator housing. However, those elements can also be provided within separate housings.
Actuation of a transmission or, for example, of a brake by means of such an actuator is not explicitly shown in FIG. 1, but it can also be performed with such an actuator. That would mean that at least one additional actuator of the kind of actuator 15 should be incorporated.
The motor vehicle 1 with the transmission 4 includes a gearshift lever 30 . A gear recognition sensor 31 and/or a shift intention sensor 32 is arranged on the gear shift lever, or on the transmission, and it detects manual actuation of the gear shift lever and thus recognizes a shift intention of the driver based on the movement of the shift lever and/or based on the applied force. Furthermore, the vehicle is equipped with a rotational speed sensor 33 , which detects the rotational speed of the transmission output shaft or of the drive wheels, respectively. Furthermore, a throttle valve sensor 34 is incorporated, which detects the throttle valve position, as well as a rotational speed sensor 35 , which detects the engine rotational speed.
The gear recognition sensor 31 directly or indirectly detects the position of the transmission internal shift elements or the gear selected in the transmission, so that by means of a signal from sensor 31 at least the selected gear is registered by the control unit. Furthermore, in the case of an analog sensor, the movement of the transmission internal shift elements can be detected, so that early recognition of the next selected gear can occur.
FIG. 2 shows a block connection diagram representing the inventive apparatus. In the control unit 15 a a signal receiving unit 50 is provided, which receives the incoming signals from various sensors and/or other electronic units. Signal receiving unit 50 receives, for example, the signals of the rotational speed of the engine (N M ) and that of the transmission input shaft (N K ) or signals representing those values. In unit 50 , for example, the performance loss V is determined based on the slippage os=engine rotational speed N M −transmission input rotational speed N K and based on the torque M K transmitted by the clutch. With regard to this feature reference is made to German Patent Publication No. DE 196 02 006, the contents of which are expressly included as part of the disclosure content of the present application.
A sensor 90 for determining the distance traveled by the vehicle, such as a tachometer or odometer, transmits a signal S representative of the distance traveled to the unit 50 or to a memory 60 . The memory receives the pair of performance loss and distance traveled values (V, S) and stores them. That storage process can be performed continuously for a specified time, or for a continuous specified distance S. The distance traveled S is determined, for example, through the addition or integration of an input value S roh , such as wheel rotational speed or drive shaft rotational speed.
A control unit 51 can, for example, be utilized for the determination of the set point value V soll for actuation of a clutch, brake, or transmission, for example, for determining an adaptive value corresponding with the pair of values (V, S) stored in memory 60 , and to calculate the current set point value V soll .
Memory 60 can be a read-write memory, an EPROM, or an EEPROM, which are typically used in computer units.
The vehicle data, such as the distance traveled, the rotational speed, or other data, can also be transmitted, for example, through a data bus, such as a CAN-bus, by other electronic units, such as the motor control, an ABS control, or other units, to the control unit 15 a.
The data in memory 60 are readable and further processable for testing and diagnostic purposes.
If, for example, the energy loss or the transmission loss is above a limit value due to slippage in the area of the clutch, a visual, or acoustic, or another form of signal can be generated, and can signal to the driver that a wear condition has been reached that makes a replacement or maintenance necessary in the future.
By means of the invention, it is useful in the case of motor vehicles to control an engine, an automated clutch, an automated clutch and/or an automated transmission, and/or an anti-lock system for brakes (ABS), and to utilize control units equipped with extensive sensors and operating data recording devices in order to determine the current operating data of the vehicle as comprehensively as possible. In that way the energy loss or transmission loss in the area of the clutch and/or in the area of a transmission, or other adaptive values or actuation values, can be recorded for a clutch or a transmission or their actuation devices.
Motor vehicles are generally equipped with engine controls, which record/detect among other things the torque produced by the engine as well as the rotational speed of the engine. In addition, a wheel rotational speed, or a signal representative of it, can be included, for example, to determine the driving speed and/or to control an anti-lock system of the vehicle's brakes. When these data are further transmitted to the control unit 15 a , the slippage of the clutch can be determined.
For the torque transmittable by the clutch, such as the clutch torque, the pedal travel can be utilized, for example, wherein by means of a clutch characteristic curve, in which the clutch torque is given as a function of the pedal travel, the transmittable torque can be determined from the pedal travel.
In another embodiment of the invention the simplified assumption can be made that the engine torque is approximately equal to the torque transmittable by the clutch.
In the case of installation of the clutch between the engine and the transmission, with the clutch engaged the transmission input speed is directly linked with the engine rotational speed, whereby when the clutch slips the transmission input speed can possibly deviate slightly from the engine rotational speed.
The transmission output shaft speed or the drive wheel speed is numerically dependent upon the transmission input speed through the gear ratio, so that based on information about the gear ratios or the transmission output shaft speed, the transmission input speed can be determined. The clutch slippage can thus be calculated from the related data.
In this connection reference is again made to German Patent Publication No. DE 196 02 006.
By calculating the energy loss based on the slippage in the area of the clutch linings and/or by calculating the power loss, the wear of the friction linings of the clutch can be determined through a characteristic curve, in which the power loss and the wear of the friction linings in millimeters are plotted. When the wear of the friction linings of the clutch reaches the extent of the wear reserve of new clutch linings, the driver of the vehicle can be alerted to the wear situation with a warning signal.
It can also prove beneficial, however, to store other adaptive parameters, such as the engagement point of the clutch, as a function of the distance traveled by the vehicle.
When in a repair shop or during another opportunity for vehicle diagnosis, the time-related development or the development of adaptive parameters with regard to the distance can be evaluated.
This allows conclusions for relevant vehicle characteristics so that timely measures can be initiated.
The patent claims submitted with the application are formulation suggestions without prejudice for obtaining further patent protection. The applicant reserves the right to claim additional features that have so far been disclosed only in the description and/or drawings.
Based on the stored data, the wear of the clutch or of other components can also be calculated and from it the resulting current engagement point of the clutch can be determined. The engagement point GP is the actuation path of the clutch at which the clutch begins to transmit torque.
References made in the sub-claims to previously mentioned features point out further developments of the object of the main claim through features of the respective sub-claim; they should not be understood as a waiver for achieving independent protection of the object for the features of the referenced sub-claims.
The objects of these sub-claims however also form independent inventions, which have formulations that are independent from the objects of the previous claims.
The invention is also not limited to the embodiment(s) of the description. Within the framework of the invention numerous alterations and modifications are possible, especially such variations, elements and combinations and/or materials that represent an invention, for example by combining or altering individual features and/or elements or procedures that are described in connection with the general description and the embodiments as well as in the claims and that are contained in the drawings and that lead to a new object or new procedures and/or procedural sequences through features that can be combined, including to the extent that they relate to manufacturing, testing and operational procedures. | A vehicle including a device for determining vehicle operational data and for determining distance traveled by the vehicle. A memory is provided for storing the operational data together with the distance traveled as paired values for subsequent diagnostic and maintenance purposes. Signals representative of engine rotational speed, transmission input rotational speed, and torque transmitted by the clutch are sensed for determining clutch performance loss values, and the performance loss values are stored in the memory as paired values along with the vehicle distance traveled. | 5 |
TECHNICAL FIELD
[0001] The present invention relates to a method for preparing a culture medium used for culturing a plant tissue and a method for culturing a plant tissue, as well as a sterilizing agent, a microbicidal agent, and a culture medium composition for culturing a plant tissue.
BACKGROUND ART
[0002] Normally, in the culturing of a plant tissue, either a culture medium in the form of a gel or solid prepared by adding a gelling agent (e.g. agarose or gellan gum) to a culture solution, or a liquid culture medium which contains no gelling agent is used. The culture medium is contained in a culture vessel, and in this state, the medium is subjected to a sterilizing treatment, after which the plant tissue is placed in the culture medium under a sterile environment (this task is hereinafter called the “inoculation”) and the culturing of this plant tissue is performed in an incubation room. Such a procedure is necessary since, if germs are allowed to enter the culture vessel, the germs will multiply due to sugar and other nutrients in the culture medium and consequently impede the growth of the plant tissue.
[0003] Normally, the sterilization of the culture medium and the culture vessel is performed with a high pressure steam sterilizer (autoclave), while the inoculation of the plant tissue is performed in a sterile room (clean bench). Accordingly, after the sterilization, the culture medium or the like must be removed from the autoclave and transferred to the sterile room. This task is cumbersome since it requires a great amount of care to avoid entry of the germs. Another problem is that the capacity of the autoclave or sterile room limits the amount of plant tissue that can be cultured, so that it is impossible to simultaneously culture a large amount of plant tissue.
[0004] Accordingly, a method by which a plant tissue can be easily cultured, even outdoors, without using a high pressure steam sterilizer and sterile room has been researched and developed.
[0005] For example, Non Patent Literature 1 (which is an academic paper put forth by the present inventor and other authors) discloses a simple method for culturing a plant tissue using a plurality of kinds of agents including a chlorine microbicide. This method includes the steps of heating a culture medium to boiling temperature to dissolve the medium, adding agents a plurality of times to the dissolved medium to sterilize the medium, immersing the culture vessel and the plant body in a liquid containing a microbicidal agent to kill bacteria, and culturing the plant body under a normal environment. According to a report in Non Patent Literature 1, the thereby obtained sterilizing or microbicidal effect is approximately comparable to those obtained by using a high pressure steam sterilizer and sterile room.
CITATION LIST
Non Patent Literature
[0000]
Non Patent Literature 1: Yoichi Mizuta, Kiyoaki Miyasaka, Yusuke Muraishi, and Motoaki Doi, “Ooto-kureebu To Kuriin Benchi Wo Mochiinai Kan-i Soshiki Baiyou Ni Okeru Biseibutsu Osenritsu No Teigen (Reduction of Microbial Contamination Rate in a Simple Tissue Culturing Method without Using Autoclave and Clean Bench)”, Horticultural Research (Japan), Vol. 9, Additional Volume 2, September, 2010, p. 298
SUMMARY OF INVENTION
Technical Problem
[0007] However, the plurality of kinds of agents used in the previously described method cannot be previously mixed. Therefore, it is necessary to separately weigh each of those agents immediately before adding them to the culture medium or immersing the culture vessel and the plant body in a liquid. Clearly, such a task is complex and troublesome.
[0008] The problem to be solved by the preset invention is to provide a method for preparing a culture medium for culturing a plant tissue and a method for culturing a plant tissue in which the sterilizing or microbicidal treatment can be easily performed and yet the plant tissue can be grown to approximately the same extent as in the case of using an autoclave and a clean bench, as well as a sterilizing agent for a culture medium for culturing a plant tissue, a microbicidal agent for a plant body, and a culture medium composition for culturing a plant tissue.
Solution to Problem
[0009] A method for preparing a culture medium for culturing a plant tissue according to the present invention developed for solving the previously described problem includes the successive processes of:
[0010] boiling a culture medium;
[0011] adding a first sterilizing agent composed of a plurality of kinds of powdery agents to the culture medium at a point in time in the boiling process;
[0012] adding a second sterilizing agent composed of a single kind of agent to the culture medium at the end of the boiling process, and dispensing the culture medium into a culture vessel; and
[0013] cooling the dispensed culture medium.
[0014] The present invention is characterized in that the first sterilizing agent to be added at a point in time in the process of boiling the culture medium is composed of a plurality of kinds of powdery agents, and the second sterilizing agent to be added at the end of the boiling process is composed of a single agent. The mixing of the different powdery agents does not alter the nature of those agents. Therefore, the first sterilizing agent can be previously prepared.
[0015] The “point in time in the boiling process” does not need to be earlier than the “end of the boiling process”; they may be at the same point in time. If the “point in time in the boiling process” coincides with the “end of the boiling process”, the first and second sterilizing agents may be previously mixed. In this case, the method for preparing a culture medium for culturing a plant tissue according to the present invention will be substantially identical to the method including the successive processes of:
[0016] boiling a culture medium;
[0017] adding a sterilizing agent composed of a plurality of kinds of powdery agents to the culture medium at a point in time in the boiling process, and subsequently dispensing the culture medium into a culture vessel; and
[0018] cooling the dispensed culture medium.
[0019] The agents composing the first sterilizing agent should preferably contain one or more substances selected from the group of sucrose fatty acid esters, nisin, natamycin, ε-polylysine, protamines, citrate, and hypochlorite, among which sucrose fatty acid esters and nisin are particularly preferable. Glycerin fatty acid esters may also be contained in addition to or in place of the sucrose fatty acid esters.
[0020] The agent composing the second sterilizing agent should preferably contain one or more substances selected from the group of captan, oxolinic acid, and hypochlorite. For the first and second sterilizing agents, agents or substances which are officially designated as food additives or agricultural chemicals should preferably be used.
[0021] A method for culturing a plant tissue according to the present invention developed for solving the previously described problem includes the processes of:
[0022] immersing a culture vessel containing a solid or semisolid culture medium in a first microbicidal composition solution containing a chlorine microbicide for a predetermined period of time;
[0023] immersing a plant tissue in a second microbicidal composition solution for a predetermined period of time; and
[0024] inoculating the plant tissue removed from the second microbicidal composition solution in the culture medium contained in the culture vessel removed from the first microbicidal composition solution, and culturing the plant tissue in the culture medium.
[0025] As the culture medium contained in the culture vessel to be immersed in the first microbicidal composition solution, the culture medium prepared by the previously described method can be preferably used.
[0026] The first microbicidal composition solution should preferably contain an agent containing sucrose fatty acid esters, in addition to the chlorine microbicide. The second microbicidal composition solution should preferably contain agents which respectively contain sucrose fatty acid esters, captan, oxolinic acid and natamycin. In this case, the agents containing the sucrose fatty acid esters and natamycin should preferably be products officially designated as food additives, while both the agent containing captan and the agent containing oxolinic acid should preferably be products officially designated as agricultural chemicals.
[0027] Furthermore, the first microbicidal composition solution may also contain CMIT (e.g. ZonenC or Kathon) in addition to the previously mentioned substances.
[0028] A sterilizing agent for a culture medium for culturing a plant tissue according to the present invention is characterized by being composed of a powdery agent containing at least sucrose fatty acid esters and nisin.
[0029] A culture medium composition for culturing a plant tissue according to the present invention is characterized by containing the previously mentioned sterilizing agent and a powdery culture-medium component.
[0030] A microbicidal agent used for culturing a plant tissue according to the present invention is an agent to be used for a microbicidal treatment of a plant body or culture vessel, characterized by being composed of a plurality of kinds of powdery agents mixed together.
Advantageous Effects of the Invention
[0031] In the method for preparing a culture medium for culturing a plant tissue according to the present invention, since the first sterilizing agent and the second sterilizing agent can be previously prepared, it is possible to easily kill bacteria in a culture vessel and culture medium without having to perform a cumbersome task. Furthermore, by using the obtained culture medium, the plant tissue can be grown to approximately the same extent as in the case of using an autoclave and a clean bench.
[0032] In the method for culturing a plant tissue according to the present invention, the microbicidal treatment can be easily performed by merely immersing the culture medium and the plant tissue in the first and second microbicidal composition solutions, respectively. The plant tissue cultured by this method can grow to approximately the same extent as in the case of using an autoclave and a clean bench.
[0033] The sterilizing agent for a culture medium for culturing a plant tissue, the microbicidal agent for a plant body, and the culture medium composition for a plant tissue according to the present invention previously contain necessary components for the sterilization of a culture medium or the microbicidal treatment of a plant body. Therefore, by using this agent or composition, the sterilization of the culture medium and the microbicidal treatment of the plant body can be easily performed.
BRIEF DESCRIPTION OF DRAWINGS
[0034] FIG. 1 illustrates a procedure for sterilizing a solid culture medium (two-time dosing mode).
[0035] FIG. 2 illustrates a procedure for sterilizing a solid culture medium (one-time dosing mode).
[0036] FIG. 3 illustrates a procedure for sterilizing a solid culture medium (medium-component mixture mode).
[0037] FIG. 4 illustrates a culturing procedure using a solid culture medium.
[0038] FIG. 5 illustrates a culturing procedure using a liquid culture medium.
[0039] FIG. 6 shows an experimental result showing the influence of the agent concentration on the growth of plants.
[0040] FIG. 7 shows an experimental result showing the influence of the combination and concentrations of agents on the sterilization of a culture medium.
[0041] FIG. 8 shows an experimental result showing the influence of the combination and concentrations of agents in the culture medium on the microbial recontamination after solidification.
[0042] FIG. 9 shows an experimental result showing the influence of the concentrations and combination of agents in the inoculating process on the sterilizing effect.
[0043] FIG. 10A shows an experimental result showing the occurrence rate of microbial contamination.
[0044] FIG. 10B shows an experimental result showing the occurrence rate of microbial contamination.
[0045] FIG. 11 shows the result of a comparative experiment on the growth of explants.
[0046] FIG. 12 shows the result of a comparative experiment showing how the growth of explants changes depending on the method used for sterilizing a liquid culture medium.
[0047] FIG. 13 shows the result of an experiment on a change in the occurrence rate of the microbial contamination in the liquid culture.
[0048] FIG. 14 shows the result of an experiment on the occurrence rate of the microbial contamination of a liquid culture medium after sterilization.
[0049] FIG. 15 shows the result of an experiment on present examples and comparative examples.
DESCRIPTION OF EMBODIMENTS
[0050] The method for culturing a plant tissue and the method for preparing a culture medium for culturing a plant tissue according to the present invention are hereinafter described with reference to specific examples. Initially described are a method for sterilizing a culture medium and a method for the microbicidal treatment of a culture vessel. The following tables 1-5 respectively show the kinds of agents, culture vessels, culture-medium compositions, inoculated bacteria, and explants, all of which were used in the sterilization examples, etc.
[0000]
TABLE 1
Used Agents
Brevity
Product
Product
Main Component
Code
Name
State
Name
Content
Manufacturer
Food
SE-L
RYOTO
Viscous
Sucrose
280
g/kg
Mitsubishi-
Additives
Sugar Ester
liquid
monolaurate
Kagaku Foods
LWA-1570
SE-P
RYOTO
Powder
Sucrose
800
g/kg
Mitsubishi-
Sugar Ester
monopalmitate
Kagaku Foods
P-1670
Nata
Natamycin
Powder
Natamycin
950
g/kg
A and Z Food
Additives Co.,
Ltd.
Nisin
Nisaplin
Powder
Nisin A
25
g/kg
Danisco
Imp
Impact N
Powder
Salmine
60
g/kg
Asama
Chemical Co.,
Ltd.
Ly
Egg-white
Powder
Egg-white
950
g/kg
A and Z Food
lysozyme
lysozyme
Additives Co.,
Ltd.
Agricultural
Cl
Chemichlon G
Grain
Available chlorine
700
g/kg
Nippon Soda
Chemicals
in hypochlorous
Co., Ltd.
acid
Cap
Orthocide-
Powder
Captan
800
g/kg
Sankei
80
Chemical Co.,
Ltd.
Ox
Wettable
Powder
Oxolinic acid
200
g/kg
Sumika Agro
powder
Manufacturing
STARNER
Co., Ltd.
Environmental
Zc
ZonenC
Water-
5-chloro-2-
133.6
g/L
Chemicrea
Disinfectants
soluble
methylmethyl-4-
Inc.
liquid
isothiazolinone
PHMB
Supermill88
Water-
polyhexamethylene
40
g/L
Epro
soluble
biguanide
Corporation
liquid
[0000]
TABLE 2
Culture Vessel
Specification
Test tube
A glass tube measuring 23 mm in inner diameter and 150 mm in length,
with a polypropylene (PP) molten plug. Capacity for culture medium,
25 mL
Plastic case
A PP case measuring 155 mm in width, 250 mm in length and 200 mm
(for solid culture medium)
in depth, with a 20-L polyethylene bag fitted therein and sealed by tying
its top. Capacity for culture medium, 1 L.
Plastic case
A PP case measuring 155 mm in width, 250 mm in length and 200 mm
(for liquid culture medium)
in depth, with a 45-L polyethylene bag fitted therein and sealed by
folding it in half and tying its top. Capacity for culture medium, 5 L.
[0000]
TABLE 3
Culture Medium
Composition
Remarks
Common
Raw water: tap water
Features
Granulated sugar, 15 g/L
Gelling Agent
Gellan gum, 2 g/L
Only used for solid culture media.
Salt
Otsuka-A
Otsuka House 1 Gou + Otsuka House 2 Gou
Composition
MS
Murashige & Skoog's inorganic salt and EDTA
Knop
Knop's salt, Murashige and Skoog's micro nutrients, and
EDTA
Additive
+Y&P
Bact Yeast Extract (2.5 g/L) and Bact Tripton (5 g/L)
Organic
+oatmeal
7.5 g/L
Substance
+mashed potato
7.5 g/L
+coconut milk
75 g/L
+coconut water
75 g/L
+potato
75 g/L, peeled, and ground with a mixer to fluid state
+banana
75 g/L, peeled, and ground with a mixer to fluid state
+beef liver
75 g/L, peeled, and ground with a mixer to fluid state
[0000]
TABLE 4
Inoculated
Bacteria
(Brevity
Code)
B5
A bacterial suspension of B5 strain, presumed to be
Bacillus subtilis , containing 10 10 cfu · mL −1 of spores
Gst
A bacterial suspension of Geobacillus stereothermophyros
ATTC7953 containing 10 8 cfu · mL −1 of spores
S3
A bacterial suspension of S3 strain, presumed to be Serratia
sp., containing 10 12 cfu · mL −1 of viable bacteria
An
A conidial powder of a filamentous fungus, presumed to be
Aspergillus niger complex. The conidial powder contains
3 × 10 6 CFU/mg of conidia.
[0000]
TABLE 5
Name
(Breed)
Abbreviated Name
Condition
Weight Per Piece
Potato
One node of potato
One node of plant cultured in vitro,
0.008-0.015
g/explant
“May
(without leaves)
without leaf blades
Queen”
One node of potato
One node of plant cultured in vitro, with
0.015-0.03
g/explant
(with leaves)
leaf blades
Potato shoot
The entire plant cultured in vitro, with
0.15-0.3
g/explant
the underground part removed
Chrysanthemum
One node of
One node of plant cultured in vitro,
0.02-0.04
g/explant
“Piato”
chrysanthemum
without leaf blades
(without leaves)
One node of
One node of plant cultured in vitro, with
0.1-0.2
g/explant
chrysanthemum
leaf blades
(with leaves)
Chrysanthemum
The entire plant cultured in vitro, with
2-4
g/explant
shoot
the underground part removed
Carnation
One node carnation
One node of carnation cultured in vitro
0.15-0.3
g/explant
“Francesco”
Saintpaulia
Saintpaulia
One leaf blade of plant cultured in vitro
0.01-0.025
g/explant
“Polar Star”
Taro
Taro
A few nodes including terminal bud of
0.1-0.3
g/explant
“Eguimo”
plant cultured in vitro
Northern
Northern
A plant cultured in vitro
0.02-0.04
g/explant
Maidenhair
maidenhair fern
Fern
prothallium
[0051] [Sterilization of Solid Culture Medium]
(1) Sterilization of Culture Medium in Solidifying Process
[0052] Solid culture media were sterilized by the following methods (1-1) through (1-3). A solid culture medium obtained by those methods is hereinafter called the “sterilized solid culture medium.”
[0053] (1-1) A method in which the culture medium is sterilized by separately adding two doses of sterilizing agents in the process of solidifying the culture medium. (This method is hereinafter called the “two-time dosing mode.” See FIG. 1 .)
[0054] 1. A culture medium is heated and boiled.
[0055] 2. A first sterilizing agent (whose composition will be described later) is added to the dissolved culture medium.
[0056] 3. The boiling state is maintained for three minutes.
[0057] 4. After a second sterilizing agent (whose composition will be described later) is added, the culture medium is dispensed into culture vessels and cooled at room temperature to solidify it.
[0058] (1-2) A method in which the culture medium is sterilized by adding one dose of sterilizing agent in the process of solidifying the medium. (This method is hereinafter called the “one-time dosing mode.” See FIG. 2 .)
[0059] 1. A culture medium is heated and boiled.
[0060] 2. After a first sterilizing agent (whose composition will be described later) is added to the dissolved culture medium, the medium is dispensed into culture vessels and cooled at room temperature.
[0061] (1-3) A method in which sterilizing agents are previously mixed in the culture-medium components. (This method is hereinafter called the “medium-component mixture mode.” See FIG. 3 .)
[0062] 1. An amount of tap water is heated and boiled.
[0063] 2. A mixture of sterilizing agents and all the culture-medium components is dissolved by pouring hot water of 90° C. or higher onto that mixture.
[0064] 3. After the culture medium is completely dissolved, the medium is dispensed into culture vessels and cooled at room temperature.
[Method of Inoculating (Culturing) Explant]
(1) Culturing on Solid Culture Medium (See FIG. 4 )
[0065] 1. An explant is immersed in a first microbicidal liquid and is subsequently removed from the liquid and drained. The first microbicidal liquid is previously prepared by dissolving, in an amount of tap water, one or more agents selected from the following agents: 2000 mg/L of P-1670 (SE-P2000), 2000 mg/L of Nisaplin (Nisin2000), 500 mg/L of wettable powder STARNER(Ox500), 10000 mg/L of Natamycin (Nata10000), 10000 mg/L of Orthocide-80 (Cap1000), and 20000 mg/L of Impact N (Imp20000).
[0066] 2. A sterilized solid culture medium contained in the culture vessels is immersed in a second microbicidal liquid, which contains one or both of the following agents: 2000 mg/L of P-1670 (SE-P2000) and 1400 mg/L of Chemichlon G (Cl1400).
[0067] 3. The culture vessels are removed from the second microbicidal composition liquid and turned upside down to drain the remaining liquid.
[0068] 4. The explant obtained in Step 1 is inoculated on the culture medium in the culture vessels obtained in Step 3, and is cultured in a standard laboratory.
(2) Culturing in Liquid Culture Medium (See FIG. 5 )
[0069] 1. A polyethylene bag is placed in a plastic case, and a culture solution is poured into the polyethylene bag.
[0070] 2. A microbicidal agent is added to and dissolved in the culture solution. The microbicidal agent is one or more of the following agents: 10 mg/L of P-1670 (SE-P10), 10 mg/L of Nisaplin (Nisin10), 2 mg/L of wettable powder STARNER (Ox2), 50 mg/L of Natamycin (Nata50), 50 mg/L of Orthocide-80 (Cap50), 100 mg/L of Impact N (Imp100), 100 mg/L of egg-white lysozyme (Ly100) and 7 mg/L of Chemichlon G (Cl7).
[0071] 3. A germ-free explant is inoculated in the culture solution obtained in Step 2, and is cultured in a normal laboratory.
[0072] The specific results of the experiments are hereinafter described.
[0073] [Influence of Agent Concentration on Growth of Plant]
[0074] The influence of a change in the concentrations of the agents used for sterilizing the culture medium on the growth of plants was investigated. The result is shown in FIG. 6 . The culture condition in this experiment was as follows:
[0075] Culture medium components: solid culture medium dosed with Otsuka-A
[0076] Culture period: 30 days
[0077] Number of plant bodies: 10
[0078] Numerical values: average±standard deviation
[0079] Sterilizing method: one-time dosing mode
[0080] Inoculating method (Culturing method): the method shown in FIG. 4 was used, with SE-P2000Cl140/SE-P2000Cl140 as the first/second microbicidal liquids, respectively.
[0081] In FIG. 6 , the “Autoclave (Conventional Method)” indicates comparative examples, in which an explant which had undergone a microbicidal treatment in an autoclave was placed in a liquid culture medium and cultured in a clean bench.
[0082] As can be seen in FIG. 6 , P1670 (SE-P) and LWA1570 (SE-L) did not negatively affect the growth of the plant when their concentration in the culture medium was 5 g/L or lower.
[0083] The natamycin agent (Nata) did not negatively affect growth when its concentration was 100 mg/L or lower. The reason why P1670 (SE-P) was added with the natamycin agent was because using only natamycin allows nonnegligible contamination by spore-forming bacteria.
[0084] Nisaplin (Nisin) did not negatively affect growth when its concentration was 500 mg/L or lower.
[0085] Wettable powder STARNER (Ox) did not negatively affect growth when its concentration was 2 mg/L or lower.
[0086] Chemichlon G (Cl) did not negatively affect growth when its concentration was 14 mg/L or lower. The concentration of the available chlorine in 14 mg/L of Chemichlon G is 10 mg/L.
[0087] Based on these results, the upper limits of the concentrations of the agents used in each sterilizing agent or microbicidal liquid were determined.
[Influence of Concentrations and Combination of Agents on Sterilization of Culture Medium]
[0088] The sterilization effect on bacteria inoculated in the solid culture medium was investigated. The culture condition was as follows:
[0089] Culture period: 30 days
[0090] Culture condition: 40° C., in the dark
[0091] Number of test tubes used in the measurement: 50
[0092] Numerical values: microbial contamination rate (the percentage of the tubes in which microbial colonies were formed)
[0093] Inoculated amount: 1 mL per 1 L of the culture medium
[0094] The result is shown in FIG. 7 . A comparison between LWA1570 and P1670 in FIG. 7 demonstrates that P1670 produces a higher degree of sterilization effect. The following facts can also be realized: Some kinds of culture media cannot be sterilized even if the agent concentration is increased; Chemichlon G must not be simultaneously added with LWA1570 or P1670; and Chemichlon G must not be added before the addition of LWA1570 or P1670.
[0095] In particular, Chemichlon G should be added within 3-15 minutes from the addition of P1670 or Nisaplin. Though the procedure of preparing the culture medium becomes slightly complex, this method allows the agent to be composed of only food additives. This method is also advantageous in that there is no need to use an oxolinic acid agent (wettable powder STARNER) which has significantly adverse effects on plants. When P1670, Nisaplin and wettable powder STARNER are combined, all of these agents can be simultaneously added.
[0000] [Influence of Concentrations and Combination of Agents in Culture Medium on Microbial Recontamination after Solidification]
[0096] A sterilized culture medium (Otsuka-A solid culture medium) was placed in 50 test tubes held in a tube stand and kept intact on a standard laboratory table (at temperatures of 14-24° C.), and the temporal change in the degree of microbial colony formation was investigated.
[0097] The result is shown in FIG. 8 .
[0098] FIG. 8 demonstrates that no colony was formed on the culture medium sterilized with P1670, Nisaplin and Chemichlon G when the vessels were sufficiently sealed so as to prevent newly invasion of microbes (i.e. the sterilization is sufficient).
[0099] However, when the vessels were not sufficiently sealed, a considerable amount of microbes reentered and formed colonies.
[0100] When P1670, Nisaplin and wettable powder STARNER were used, newly invasion of bacteria was decreased. When Natamycin was also used in addition to those agents, newly invasion of filamentous fungi was also dramatically decreased, although open storage of the culture was not possible.
[0101] However, the open storage was made possible by further adding ZonenC. It was also found that, when Natamycin was not added, the open storage was impossible even when ZonenC was added.
[0102] [Influence of Concentrations and Combination of Agents in Inoculating Process on Sterilizing Effect]
[0103] An experiment was conducted to determine how the sterilizing effect after inoculation is related to the concentrations and combination of the agents used in the microbicidal liquid for explants and the microbicidal liquid for culture vessels. The experimental condition was as follows:
[0104] Solid culture medium: dosed with Otsuka-A
[0105] Sterilizing method: autoclave
[0106] Method of inoculation of bacteria: on culture medium surface [as for “B5” and “S3”, 50 μL per test tube of the bacterial suspension was dropped onto the surface of the culture medium; and as for “An”, 10 mg per test tube of either a conidial powder or a conidial powder diluted with a-starch to a predetermined dilution ratio was poured onto the culture medium]; or on explant [as for “B5” and “S3”, the explant was immersed in the bacterial suspension (whereby 10 μL per explant was attached); and as for “An”, the explant was coated with either a conidial powder or a conidial powder diluted with a-starch to a predetermined dilution ratio (whereby 5 mg per explant was attached)]
[0107] Explant: potato
[0108] Inoculation method: the method shown in FIG. 4
[0109] Culture period: 14 days
[0110] The result is shown in FIG. 9 . From the result obtained by treating the culture vessel with Chemichlon G (Cl2800) without inoculating any explant, it has been determined that the formation of “An” colony could not be prevented even when the concentration of the available chlorine was increased to a high level of 2000 mg/L.
[0111] When P-1670 (SE-P) was added, the colony formation could be prevented by immersing the culture vessel in a liquid containing 700 mg/L or higher amounts of Chemichlon G (equivalent to 500 mg/L or higher amounts of available chlorine).
[0112] Furthermore, when Orthocide (Cap), wettable powder STARNER (Ox), Natamycin (Nata) or the like was added at low concentrations, the colony formation could be prevented even with a liquid whose Chemichlon-G concentration was decreased to 140 mg/L (equivalent to 100 mg/L of available chlorine).
[0113] When bacteria were inoculated on the explant, it was impossible prevent the colony formation by immersing the explant in the same microbicidal liquids as used in the case where no explant was inoculated.
[0114] The colony formation could not be prevented even when the inoculating concentration was decreased by a factor of one thousand.
[0115] “B5” could be sterilized by treating the explant with a microbicidal liquid containing 200 mg/L or higher amounts of wettable powder STARNER (Ox). However, this liquid could not prevent the formation of “An” and “S3” colonies. The formation of “S3” colony could be prevented to some extent by treating the explant with a microbicidal liquid which contained 10000 mg/L or higher amounts of Orthocide-80 (Cap). However, this liquid could not prevent the formation of “An” and “B5” colonies. The formation of “An” colony could be prevented to some extent by treating the explant with a microbicidal liquid which contained 10000 mg/L or higher amounts of Natamycin (Nata). However, this liquid could not prevent the formation of “S3” and “B5” colonies. When all of the three kinds of agents were added, the three kinds of bacteria could be prevented from forming colonies (for “An”, this effect could be obtained when its inoculating concentration was decreased by a factor of one hundred or more). Such a tendency barely changed even when the kind of microbicidal liquid for treating the culture vessel was altered.
[0116] Adding Nisaplin (Nisin) and Salmine lowered the microbicidal effect on “An”, rather than improving it.
[0117] [Occurrence Rate of Microbial Contamination]
[0118] The occurrence rate of contamination by external microbes after inoculation was investigated for various combinations of the sterilizing method for culture media, treatment liquid for explants, and treatment liquid for culture vessels. The list in FIG. 10A shows the kinds of sterilizing composition, microbicidal liquid and other information on each experiment. FIG. 10B shows the occurrence rate of microbial contamination.
[0119] The information in these figures demonstrates that the microbial contamination can be prevented by appropriately determining the kinds of agents and their concentrations. In particular, the contamination of the potato, which is prone to being contaminated by microbes in the inoculating process, could be suppressed by increasing the agent concentrations.
[Comparison of Growth of Explants]
[0120] Based on the previously described results, sterilizing compositions and microbicidal liquids were prepared by appropriately combining the agents with concentrations determined so as to avoid adverse effects on the growth of explants. Using those compositions and liquids, explants were actually cultured and their growths were compared. The culture condition was as follows:
[0121] Culture vessel: test tube
[0122] Culture medium: Otsuka-A, solid
[0123] Culture condition: cultured for 30 days, with one explant in each test tube
[0124] Number of measurements: 10 test tubes
[0125] The result is shown in FIG. 11 . As can be seen in FIG. 11 , for most of the plants, whichever methods were used for the culturing and medium sterilization did not significantly affect their growth. However, Saintpaulia and northern maidenhair fern prothallium, both of which are sensitive to agents, could not be inoculated without a clean bench. It is most likely that, for such plants, not only the microbicidal liquid applied to the explant but also ZonenC contained in the culture medium is also harmful. It should be noted that Saintpaulia, northern maidenhair fern prothallium and the like could also be successfully cultured by omitting the addition of ZonenC to the culture medium or diluting the microbicidal liquid used in the explant-inoculating process.
[0126] [Comparison of Growth of Explants Due to Difference in Method of Sterilization of Liquid Culture Medium]
[0127] Concerning the liquid culture, an experiment was conducted to investigate a change in the growth of explants depending on the method of sterilizing the liquid culture medium. Explants were placed in a liquid culture medium dosed with Otsuka-A and cultured for 30 days. The result is shown in FIG. 12 . From FIG. 12 , the following facts have been established: Impact N does not adversely affect growth when its concentration is 500 mg/L or lower; Orthocide-80 does not adversely affect growth when its concentration is 50 mg/L or lower; and Chemichlon G, when its concentration is 7 mg/L or lower, can produce a sufficient sterilizing effect for achieving a growth which equals or even exceeds the growth achieved by the autoclaving method.
[0128] [Difference in Occurrence Rate of Microbial Contamination in Liquid Culture]
[0129] The microbial contamination rate was compared between the case of inoculating bacteria in the culture medium and the case of inoculating bacteria on the explant.
[0130] The inoculating concentration of the bacteria, the kind of plant body, etc. were as follows:
[0131] Culture medium: As for “B5” and “S3,” 1 mg/L was added to the culture medium. As for “An”, 0.1 g/L of its conidial powder was added.
[0132] Plant body: An explant (potato shoot) which had been immersed in a culture solution of “B5” or “S3” was inoculated, or an explant coated with diluted conidospores of “An” was inoculated.
[0133] Number of measurements: 5 bags, each sample
[0134] The result is shown in FIG. 13 . As can be seen in FIG. 13 , in the case of the liquid culture medium, similarly to the solid culture medium, the microbes inoculated in the culture medium showed a higher contamination rate than those inoculated on the explant. The microbial contamination rate by “An” was particularly high, which proves that this type of contamination is difficult to prevent.
[0135] [Occurrence Rate of Microbial Contamination of Liquid Culture Medium after Sterilization]
[0136] The contamination rate by external bacteria after sterilization of a liquid culture medium was investigated. In any cases, the result was obtained under the condition that the inoculation of explants was performed in a common room with no bacteria inoculated. The result is shown in FIG. 14 . As can be seen in FIG. 14 , adding the egg-white lysozyme was not necessary to prevent microbial contamination. The microbial contamination rate increased when any one of the following agents was omitted: SE-P, Nisin, Ox, Nata, Cap, Imp10 and Cl7.
[0137] Specific examples of the present invention and the comparative examples will be hereinafter described. The culture medium and culture vessel used for the culturing as well as other information are as follows:
(1) Culture Medium
[0138] A culture medium dosed with Otsuka-A (not diluted)+ammonium sulfate (0.5 g/L), sucrose (15 g/L) and gellan gum (2 g/L)
[0139] Yeast extract (2.5 g/L), peptone (5 g/L) and other ingredients (75 g/L, crushed with a mixer) were added to the culture medium.
(2) Culture Vessel
[0140] A test tube with an inner diameter of 23 mm, with a plastic molten plug
(3) Amount of Culture Medium
[0141] 30 mL, with one explant inoculated in each culture vessel
(4) Culture Condition
[0142] “20° C.+Explant”: white fluorescent lamp 30 μmol/m 2 ·s, 16-hour day length, day/night temperature=23° C./20° C.
[0143] “38° C.”: 38-40° C. in the dark
(5) Culture Period
[0144] For approximately 30 days from the day after the culture medium was prepared
(6) Explant
[0145] A piece (one or two nodes) of a cultured plant body of potato or chrysanthemum
(7) Number of Cultured Plants
[0146] 50 pieces (25 pieces of potato and 25 pieces of chrysanthemum )
(8) Inoculated Thermoduric Spore and Its Density
[0147] Thermoduric spores of B5 strain (presumed to be Bacillus subtilis ) were inoculated at a density of 1×10 10 CFU per 1 L of culture medium.
[0148] The culturing was performed either in the one-time dosing mode or in two-time dosing mode.
Example 1
[0149] The process steps in this example are as follows:
[0150] 1. After the culture medium is heated and boiled, a first sterilizing agent composed of a mixture of SE-P (0.2 g/L) and nisin (0.2 g/L) is added to the dissolved culture medium. Both SE-P and nisin are powdery agents.
[0151] 2. The boiling state is maintained for two minutes.
[0152] 3. After Cl (3 mg/L) as a second sterilizing agent is added, the culture medium is dispensed into the culture vessels and cooled at room temperature to solidify it.
Example 2
[0153] This example is the same as Example 1 except that the boiling is continued for five minutes. The process steps are as follows:
[0154] 1. After the culture medium is boiled, a first sterilizing agent composed of a mixture of SE-P (0.2 g/L) and nisin (0.2 g/L) is added.
[0155] 2. The boiling state is maintained for five minutes.
[0156] 3. After Cl (3 mg/L) is added, the culture medium is dispensed into the culture vessels and cooled at room temperature.
Example 3
[0157] This example is the same as Example 1 except that the boiling is continued for 10 minutes. The process steps are as follows:
[0158] 1. After the culture medium is boiled, a first sterilizing agent composed of a mixture of SE-P (0.2 g/L), nisin (0.2 g/L) and A (5 mg/L) is added.
[0159] 2. The boiling state is maintained for 10 minutes.
[0160] 3. After Cl (2 mg/L) is added, the culture medium is dispensed into the culture vessels and cooled at room temperature.
Example 4
[0161] This example is the same as Example 1 except that the boiling is continued for 30 minutes. The process steps are as follows:
[0162] 1. After the culture medium is boiled, a first sterilizing agent composed of a mixture of SE-P (0.2 g/L) and nisin (0.2 g/L) is added.
[0163] 2. The boiling state is maintained for 30 minutes.
[0164] 3. After Cl (2 mg/L) is added, the culture medium is dispensed into the culture vessels and cooled at room temperature.
[0165] Comparative Examples are hereinafter described. The process steps in Comparative Examples are basically the same as those of Examples 1-4 except that each of the two kinds of agents was individually weighed and added after the culture medium is boiled as well as after the continued boiling is completed.
Comparative Example 1
[0166] 1. After the culture medium is heated and boiled, Cl (1.4 mg/L) and SE-L (0.5 g/L) are individually weighed and added.
[0167] 2. The boiling state is maintained for three minutes.
[0168] 3. After Cl (1.4 mg/L) and nisin (0.2 g/L) are individually weighed and added, the culture medium is dispensed into the culture vessels and cooled at room temperature.
Comparative Example 2
[0169] This example is the same as Comparative Example 1 except that SE-L (which is one of the agents added to the culture medium after the culture medium is boiled) is changed to SE-P which also contains sucrose fatty acid esters. The process steps are as follows:
[0170] 1. After the culture medium is heated and boiled, Cl (1.4 mg/L) and SE-P (0.2 g/L) are individually weighed and added.
[0171] 2. The boiling state is maintained for three minutes.
[0172] 3. After Cl (1.4 mg/L) and nisin (0.2 g/L) are individually weighed and added, the culture medium is dispensed into the culture vessels and cooled at room temperature.
Comparative Example 3
[0173] In this example, all of the four kinds of agents are added after the culture medium is boiled, and the obtained culture medium is immediately dispensed into the culture vessels. The process steps are as follows:
[0174] 1. After the culture medium is heated and boiled, Cl (3 mg/L), SE-P (0.2 g/L) and nisin (0.2 g/L) are individually weighed and added.
[0175] 2, The culture medium is dispensed into the culture vessels and cooled at room temperature.
Comparative Example 4
[0176] In this example, the entire amount of Cl is added earlier, while SE-P is added later. The process steps are as follows:
[0177] 1. After the culture medium is heated and boiled, Cl (3 mg/L) is weighed and added.
[0178] 2. The boiling state is maintained for five minutes.
[0179] 3. After SE-P (0.2 mg/L) and nisin (0.2 g/L) are individually weighed and added, the culture medium is dispensed into the culture vessels and cooled at room temperature.
[0180] Using the culture media prepared by the methods of Examples 1-4 and Comparative Examples 1-4, the culturing was performed for 30 days by the previously described culturing method. The result is shown in FIG. 15 .
[0181] In Comparative Examples 1 and 2 (which are conventional culture-medium sterilization methods developed by the present inventor), there was no test tube in which a colony of spore-forming bacteria was formed, which demonstrates that sufficient sterilizing effects can be obtained by those methods. However, the agents used in Comparative Examples 1 and 2 cannot be previously mixed. Specifically, SE-L used as the source of SE in Comparative Example 1 is a viscid liquid. Although nisin is a powdery agent, its nature may possibly alter if it is previously mixed, since Cl, which is to be simultaneously added, is a strong oxidizing solid. In Comparative Example 2, SE-P used as the source of SE is a powdery agent and cannot be previously mixed as well, since Cl, which is to be simultaneously added, is a strong oxidizing solid. Accordingly, it is necessary to perform the cumbersome task of individually weighing and adding the two kinds of agents in the boiling phase as well as after the continued boiling.
[0182] By contrast, Comparative Example 3 is an example in which all the agents are simultaneously added in order to decrease the amount of labor. However, in this example, colonies of spore-forming bacteria were formed in some of the culture media, which means that the sterilizing effect was lower than Comparative Examples 1 and 2.
[0183] On the other hand, in Examples 1-4, the two agents (SE-P and nisin) to be added in the boiling phase are powdery agents and can be previously mixed. Furthermore, there is only one kind of agent to be added after the continued boiling. Therefore, in terms of the number of times of weighing the agents and the adding task, Examples 1-4 are superior to Comparative Examples 1 and 2. As for the sterilizing effect, which was measured by the number of test tubes in which colonies of spore-forming bacteria were formed, Example 1 (with a boiling period of two minutes) was inferior to Comparative Examples 1 and 2, but was superior to Comparative Example 3. Examples 2, 3 and 4 with longer boiling periods of 5, 10 and 30 minutes, respectively, produced even higher sterilizing effects: colonies of spore-forming bacteria were formed only on the culture medium to which banana was added. In particular, in Examples 2 and 3, the colony formation ratio of the spore-forming bacteria on the banana-added culture medium was as low as 5×10 −10 . Thus, it has been proved that sufficient sterilizing effects can be obtained.
[0184] In any of the previous examples, food additives were used as the agents for sterilizing culture media. It is also possible to use agricultural chemicals. Furthermore, the following variations are also possible.
<Variation 1>
[0185] 1. After the culture medium is boiled, 0.25 mg/L of a mixed agent composed of P-1670, Nisaplin, natamycin, wettable powder STARNER (agricultural chemical) and dextrin mixed at a ratio by weight of 100:100:10:1:39 is added.
[0186] By this Variation 1, the amount of bacteria entering the culture medium after the cooling and solidifying step can be decreased, so that the culture vessel does not need to be sealed when it is stored.
<Variation 2>
[0187] 1. A mixture of 0.25 g/L of a mixed agent (composed of P-1670, Nisaplin, natamycin, wettable powder STARNER (agricultural chemical) and dextrin mixed at a ratio by weight of 100:100:10:1:39), 20 g/L of granulated sugar, 2 g/L of gellan gum, 1.5 g/L of Otsuka House 1 Gou and 1 g/L of Otsuka House 2 Gou is prepared. Subsequently, 1 L of boiled water is poured onto 25 g/L of the obtained mixture and thoroughly stirred to dissolve the mixture.
[0188] According to this Variation 2, a sterilized culture medium can be created by simply pouring hot water onto an amount of powder.
<Variation 3>
[0189] This is a culture medium sterilization method suitable for performing the liquid culturing at room temperature. In this method, 0.25 g/L of a mixed agent (composed of P-1670, Nisaplin, natamycin, Impact N, Orthocide-80 and wettable powder STARNER (agricultural chemical) mixed at a ratio by weight of 4:4:20:51:20:1) and 7 mg/L of Chemichlon G are added to a culture medium having an approximately room temperature, and the culture medium is sealed.
[0190] By this method, a plant culture medium having a simple composition mainly containing typical salts, vitamins and plant growth regulators can be sufficiently sterilized if the degree of contamination by thermoduric spores is not higher than approximately 10000 CFU/L.
<Variation 4>
[0191] This is a method for sterilizing a plant tissue (a plant piece or plant body), which uses agricultural chemicals and food additives. Specifically, a plant tissue is immersed in an aqueous solution containing P-1670 (1 g/L), natamycin (10 g/L), wettable powder STARNER (10 g/L) and Orthocide-80 (10 g/L). Subsequently, the plant tissue is introduced in a culture medium sterilized by the method of Example 5 or Variation 1, and the vessel is sealed. In the case of Example 5, the culture medium is immersed together with its vessel in a solution containing 1 g/L of P-1670 and 1.43 g/L of Chemichlon G (hypochlorite).
[0192] By this method, plants with almost any degree of external contamination can be sterilized.
<Variation 5>
[0193] This is a method for sterilizing a plant tissue, which uses food additives. Specifically, a plant is immersed in an aqueous solution of P-1670 (1 g/L), natamycin (10 g/L) and Nisaplin (10 g/L). Subsequently, the plant is introduced in a culture medium sterilized by the method of Examples 5 or Variation 2, and the vessel is sealed. In the case of Example 5, the culture medium is immersed together with its vessel in a solution containing P-1670 (1 g/L) and Chemichlon G (1.43 g/L).
[0194] The degree of sterilization by this method is sufficiently high to perform the sterile culturing of an explant without using a clean bench. | A culture medium for culturing a plant tissue includes: boiling a culture medium; adding a first sterilizing agent composed of a plurality of kinds of powdery agents to the culture medium; adding a second sterilizing agent composed of a single kind of agent to the culture medium; dispensing the culture medium into a culture vessel; cooling the dispensed culture medium; making the cooled culture medium and a plant tissue wet with a plurality of kinds of liquid agents; and introducing the plant tissue in the culture medium. By this invention, a method for preparing a culture medium for culturing a plant tissue and a method for inoculating a plant tissue can be provided in which the sterilizing or microbicidal treatment can be easily performed and yet the plant tissue can be grown to approximately the same extent as in the case of using an autoclave and a clean bench. | 2 |
CROSS-REFERENCES
[0001] This application is related to U.S. provisional application No. 60/593,267, filed Dec. 30, 2004, entitled “Hinge”, naming Kevin J. Schoolcraft and Daniel J. Van Epps, Jr., as the inventors. The contents of the provisional application are incorporated here by reference in their entirety, and the benefit of the filing date of the provisional application is hereby claimed for all purposes that are legally served by such claim for the benefit of the filing date.
BACKGROUND
[0002] This invention relates generally to a mobile communication device, and more particularly to a mobile terminal used in a wireless communication system wherein the mobile terminal includes two body portions which are relatively rotatable and a hinge for connecting the two body portions of the mobile terminal.
[0003] A mobile terminal is used for sending and receiving information in a wireless communication system, such as a mobile telephone in a cellular telephone system. A mobile telephone typically includes a display and input mechanisms, such as keypads, buttons, and the like, which are used to control the mobile telephone. The display is used for viewing information and the input mechanisms typically provide for data entry, as well as control of any multi-media interface including the display.
[0004] A mobile terminal may be adapted to fold in order make the mobile terminal more compact when not in use. One type of folding mobile terminal is sometimes referred to as a “flip phone”, wherein the housing of the mobile telephone includes two body portions pivotally joined at one end such that one body portion serves as a “flip” cover. In this arrangement, the body portions of the housing are moveable between an open position and a closed position. In the open position, the display and a keypad are visible and accessible. In the closed position, the display and keypad are substantially concealed.
[0005] Another type of folding mobile telephone is sometimes referred to as a “jackknife phone”. A jackknife phone has a housing including two body portions joined at their ends which pivot about an axis perpendicular to the longitudinal plane of the housing. This configuration has the advantage of allowing for the display to always be on the outside of the mobile telephone. However, the mechanical and electrical connections between the body portions is complex. Specifically, the wiring and connectors for several dozen small wires electrically connecting the electronic components in the two body portions must pass through a mechanical hinge joining the body portions. Because of the small size of the hinge, a plurality of smaller connectors are used. Flat flexible cable is difficult to use in this application because bending of the flat cable can lead to damage.
[0006] For the foregoing reasons, there is a need for a mobile terminal for use in a wireless communication system which functions as a jackknife phone and is adapted to allow efficient assembly and electrical connection of the component parts of the mobile terminal.
SUMMARY
[0007] According to the present invention, a hinge is provided for use in a mobile terminal including at least two body portions. The hinge comprises a first hinge portion defining an opening and having a slot extending from the periphery of the first hinge portion to the opening, and a second hinge portion defining an opening and having a slot extending from the periphery of the second hinge portion to the opening. The first hinge portion is adapted to be secured to one of the two body portions, and the second hinge portion is adapted to be secured to the other of the two body portions. The first hinge portion and the second hinge portion are rotatably connected such that the openings are aligned. The first and second hinge portions are relatively rotatable between a first position where the slot in the first hinge portion and the slot in the second hinge portion are aligned for allowing access to the openings of the first and second hinge portions from the exterior of the hinge, and a second position where the slot in the first hinge portion and the slot in the second hinge portion are not aligned and the openings of the first and second hinge portions cannot be accessed from the exterior of the hinge.
[0008] Also according to the present invention, a mobile is provided and comprises a first housing member, a second housing member, and first and second hinge portions each defining an opening and having a slot extending from their periphery to the openings. The second hinge portion is rotatably connected to the first hinge portion such that the openings are aligned. The first and second hinge portions are relatively rotatable between a first position where the slot in the first hinge portion and the slot in the second hinge portion are aligned for allowing access to the openings of the first and second hinge portions from the exterior of the hinge, and a second position where the slot in the first hinge portion and the slot in the second hinge portion are not aligned and the openings of the first and second hinge portions cannot be accessed from the exterior of the hinge. The first hinge portion is secured to the first housing member the second hinge portion is secured to the second housing member such that the housing members are rotatable about an axis transverse to the longitudinal axis of the housing.
[0009] Further according to the present invention, a method is provided for connecting a first housing member of a mobile terminal and a second housing member of the mobile terminal such that the first and second housing members are rotatable an axis transverse to the longitudinal axis of the housing members. The method comprises the steps of providing a hinge including a first hinge portion defining an opening and having a slot extending from the periphery of the first hinge portion to the opening, and a second hinge portion defining an opening and having a slot extending from the periphery of the second hinge portion to the opening. The second hinge portion is rotatably connected to the first hinge portion such that the openings are aligned. Next, the relative position of the first hinge portion and the second hinge portion is selected such that the slot in the first hinge portion and the slot in the second hinge portion are aligned for allowing access to the openings of the first and second hinge portions from the exterior of the hinge. An electrical connector is disposed into the openings through the slots in the first hinge portion and the second hinge portion, and the first hinge portion rotated relative to the second hinge portion such that the slot in the first hinge portion and the slot in the second hinge portion are not aligned for capturing the electrical connector in the hinge. The first hinge portion is secured to the first housing member, and the second hinge portion is secured to the second housing member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] For a more complete understanding of the present invention, reference should now be had to the embodiments shown in the accompanying drawings and described below. In the drawings:
[0011] FIG. 1 is a front perspective view of an embodiment of a mobile terminal according to the present invention in a folded position.
[0012] FIG. 2 is a front perspective view of the mobile terminal shown in FIG. 1 with the mobile terminal in an open position.
[0013] FIG. 3 is a front perspective of an embodiment of a hinge for use with a mobile terminal according to the present invention.
[0014] FIG. 4 is a front perspective exploded view of the hinge as shown in FIG. 3 .
[0015] FIG. 5 is a rear perspective view of the hinge as shown in FIG. 3 .
[0016] FIG. 6 is a rear perspective exploded view of the hinge as shown in FIG. 5 .
[0017] FIG. 7 is a cross-section view of the hinge as shown in FIG. 3 taken along line 7 - 7 of FIG. 3 .
[0018] FIG. 8 is a front elevation view of the hinge as shown in FIG. 3 in a first position with the slots of parts comprising the hinge aligned.
[0019] FIG. 9 is a front elevation view of the hinge as shown in FIG. 8 in a second position.
[0020] FIG. 10 is a perspective view of the hinge as shown in FIG. 3 in place on a housing of a mobile terminal shown in phantom.
[0021] FIG. 11 is a front elevation view of the hinge as shown in FIG. 3 in a position on a mobile terminal shown in phantom and corresponding to the folded position of the mobile terminal as shown in FIG. 1 .
[0022] FIG. 12 is a front elevation view of the hinge as shown in FIG. 3 in a position on a mobile terminal shown in phantom and corresponding to the open position of the mobile terminal as shown in FIG. 2 .
DESCRIPTION
[0023] Certain terminology is used herein for convenience only and is not to be taken as a limitation on the invention. For example, words such as “upper,” “lower,” “left,” “right,” “horizontal,” “vertical,” “upward,” and “downward” merely describe the configuration shown in the FIGs. Indeed, the components may be oriented in any direction and the terminology, therefore, should be understood as encompassing such variations unless specified otherwise.
[0024] As used herein, the term “keypad” is used to mean any type of input device including a touch sensitive area or areas, which may include predefined key positions or a gesture area. Further, the term “keypad” is not intended to be limited to a keypad based on contacting switch technology. Rather, “keypad” as contemplated by this disclosure is intended to refer to any type of input technology that might be referred to as such, including a non-contacting type more typically referred to as a “touchpad” in which the proximity of conductive bodies is sensed.
[0025] Referring now to the drawings, wherein like reference numerals designate corresponding or similar elements throughout the several views, a mobile terminal according to the present invention is shown in FIGS. 1 and 2 and generally designated at 20 . The mobile terminal 20 is adapted for use in a wireless communication network and, in the embodiment shown, the mobile terminal 20 is a cellular telephone, which may be conventional except as otherwise provided in this description. The mobile terminal 20 comprises a housing 22 which may be of any desired size and shape; however, as described above, the trend is toward a smaller mobile terminal 20 . The housing 22 contains electronic components that are operable to transmit and receive telecommunication signals, as is known in the art, and for operating other functions of the mobile terminal 20 .
[0026] Referring to FIGS. 1 and 2 , the housing 22 includes an upper portion 24 and a lower portion 26 . The upper portion 24 of the housing 22 includes an ear piece 28 , or speaker, for emitting sound and a display 30 for displaying alphanumeric text and graphics and other images. The lower portion 26 of the housing 22 includes a microphone 32 for inputting sound and a keypad apparatus 34 including alphanumeric and function keys 36 that can receive tactile input. The upper portion 24 and the lower portion 26 of the housing 22 are electrically connected so that the user can use the keypad 34 for tactile input to enter data, make telephone calls, interact with an image on the display 30 , or otherwise control operation of the mobile terminal 20 . Various other controls may also be provided on the housing 22 , such as special purpose keys (not shown) that control one or more functional aspects of the mobile terminal 20 . For example, in a mobile terminal 20 including a camera function, one of the special purpose keys can act as a shutter release button. Because there are many types of mobile terminal housings 22 and associated components that are well known in the art and that may be utilized to practice the present invention, a more detailed description of these components is not required. It is understood that the present invention is not directed to any particular style of housing.
[0027] The upper portion 24 and the lower portion 26 of the housing 22 are joined adjacent their ends such that the upper portion 24 and the lower portion 26 are relatively rotatable in a horizontal plane through a possible range of up to about 360°. In this configuration, the housing 22 functions as a “jackknife phone”, wherein the upper portion 24 and the lower portion 26 of the housing 22 are moveable between a closed position, shown in FIG. 1 , and an open position shown in FIG. 2 . In the closed position, the inner surface of the upper portion 24 of the housing 22 is in close and complementary registration with the inner surface of the lower portion 26 of the housing 22 such that the keypad 34 is substantially concealed. Because the display 30 is coincident with the outer surface of the upper portion 24 of the housing 22 , the display 30 is visible whether the mobile terminal 20 is in the closed or the open position. In the open position, both the display 30 and the keypad 34 are visible and accessible to a user.
[0028] An embodiment of a hinge assembly for use with a mobile terminal 20 according to the present invention is shown in FIGS. 3-7 and generally designated at 40 . The hinge assembly 40 comprises a base plate 42 , a spacer 43 , a pivot plate 44 , a key ring 46 , a wave spring 48 , a retainer 50 and a split grommet 52 .
[0029] The base plate 42 is a generally rectangular plate and defines a central opening 54 having opposed linear edges 53 . The opening 54 is centered in a recess 57 formed in the inner surface of the base plate 42 . A linear slot 55 extends from the periphery of the base plate 42 and opens into the central opening 54 . A plurality of mounting ears 56 are spaced around the periphery of the base plate 42 . In the embodiment shown in the FIGs., four mounting ears 56 are located at the corners of the base plate 42 . Each of the mounting ears 56 has a mounting hole 58 for receiving a threaded fastener (not shown). A detent 60 integral with the periphery of the base plate 42 extends inwardly from between the lower mounting ears 56 .
[0030] The spacer 43 is a hollow, generally cylindrical element having a linear longitudinal slot 62 along one side. Lips 61 , 63 extend axially from each end of the spacer 43 . The cross-section of the lip 61 at the inner end of the spacer 43 corresponds to the shape of the central opening 54 in the base plate 42 . The inner end lip 61 of the spacer 43 is non-rotatably fixed in the central opening 54 of the base plate 42 by swaging, press fit, or other suitable means, such that the slot 62 in the spacer 43 is aligned with the slot 55 in the base plate 42 . The spacer 43 projects inwardly from the base plate 42 .
[0031] The pivot plate 44 is also a generally rectangular plate and defines a central circular opening 64 for rotatably receiving the spacer 43 . A linear slot 66 extends from the periphery of the pivot plate 44 and opens into the central opening 64 . A plurality of mounting ears 68 are spaced around the periphery of the pivot plate 44 . In the embodiment shown, four mounting ears 68 are located at the corners of the pivot plate 44 . Each of the mounting ears 68 has a mounting hole 70 for receiving a threaded fastener (not shown). Two inwardly projecting tangs 72 are punched into the pivot plate 44 at circumferentially spaced locations adjacent to the central opening 64 .
[0032] The key ring 46 is a circular member and defines a central circular opening 74 for rotatably receiving the spacer 43 . The key ring 46 has a slot 78 that opens into the circular opening 74 . A bell-shaped projection 76 radially extends from the periphery of the key ring 46 . The key ring 46 slidingly fits in a fence 73 on the inner surface of the pivot plate 44 such that the projection 76 on the key ring 46 is free to rotate between the tangs 72 .
[0033] The wave spring 48 is a thin C-shaped member and has curved bends at opposed points to impart elasticity to the spring 48 . The wave spring 48 defines a central opening 80 that corresponds to the exterior surface of the spacer 43 for non-rotatably receiving the spacer 43 . The ends 83 of the wave spring 48 include outturned flanges 81 . When joined, a gap 82 defined between the ends 83 of the wave spring 48 is aligned with the slots 55 , 62 in the spacer 43 and the base plate 42 .
[0034] The retainer 50 is a circular member and defines a central opening 84 . A slot 86 in the retainer 50 opens into the central opening 84 . The cross-section of the lip 63 at the outer end of the spacer 43 corresponds to the shape of the central opening 84 in the base plate 50 . The outer end lip 63 of the spacer 43 is non-rotatably fixed in the central opening 84 of the retainer 50 by swaging, press fit, or other suitable means, such that the slot 86 in the retainer 50 is aligned with the slot 62 in the spacer 43 , and thus the gap 82 in the wave spring 48 and the slot 55 in the base plate 42 . It is understood, therefore, that the base plate 42 , the spacer 43 , the wave spring 48 and the retainer 50 rotate together relative to the pivot plate 44 and the key ring 46 , with the slots 55 , 62 , 86 in the base plate 42 , the spacer 43 , and the retainer 50 and the gap 82 in the wave spring 48 permanently aligned. The retainer 50 includes a plurality of circumferentially spaced, inwardly projecting flanges 88 around the periphery of the retainer 50 for receiving the wave spring 48 . A portion of the periphery of the retainer 50 is removed from each side of the slot 86 for receiving the flanges 81 on the ends 82 of the wave spring 48 .
[0035] The wave spring 48 is disposed between the pivot plate 44 and the retainer 50 . The wave spring 48 exerts an elastic force in a longitudinal direction on the pivot plate 44 for biasing the pivot plate 44 into the base plate 42 such that the fence 73 and the key ring 46 are slidingly received in the recess 57 in the base plate 42 . The wave spring 48 functions to generate friction against the pivot plate 44 for providing some resistance to movement as the hinge 40 is rotated.
[0036] The split grommet 52 is a hollow cylindrical element and is preferably formed from rubber. The grommet 52 includes a body portion 90 having a radial flange 92 at one end and a linear longitudinal slot 94 along one side. As seen in the FIGs., the grommet 52 is received in the spacer 43 such that the flange 92 engages against the outer lip 63 of the spacer 43 .
[0037] Although not shown in the FIGs., it is understood that the upper portion 24 and the lower portion 26 of the housing 22 each have various electric circuits therein. For example, the upper portion 24 may be equipped with circuitry for operation of the display 30 , the speaker 28 and the like, and the lower portion 26 may be equipped with a main board having circuitry for operation of the mobile terminal 20 . Electrical wires, or a flexible printed circuit, used for connecting the electric circuitry in the upper portion 24 with the electric circuitry in the lower portion 26 of the housing 22 pass between the housing portions via through-holes at the point of connection of the hinge 40 to the housing 22 , as is known in the art. The electrical wires and flexible printed circuit are not shown to add clarity to the FIGs.
[0038] Referring to FIG. 8 , during assembly of the mobile terminal 20 , the pivot plate 44 and key ring 46 are rotated relative to the other parts comprising the hinge assembly 40 for aligning the slot 66 in the pivot plate 44 with the slot 55 in the base plate 42 . As described above, the slot 55 in the base plate 42 is permanently aligned with the slot 62 in the spacer 43 , the gap 82 in the wave spring 48 and the slot 86 in the retainer 50 . Thus, as seen in FIG. 8 , a passage 100 is created from the periphery of the hinge assembly 40 to the central opening through the hinge 40 as defined by the interior of the spacer 43 . It is understood that the grommet 52 is similarly rotated such that the slot 94 is also aligned with the passage 100 . This allows the user to slip the electrical wires or flexible printed circuit into the central opening of the hinge assembly 40 . The pivot plate 44 and the key ring 46 are then rotated relative to the other parts comprising the hinge assembly 40 until the hinge assembly is in the position shown in FIG. 9 , thereby capturing the wires or printed circuit in the spacer 43 in the hinge assembly 40 . The grommet 52 may then be rotated relative to the spacer 43 to misalign the slit in the grommet 52 and the slot 55 in the base plate 42 . It is understood that the grommet 52 rotates freely in the spacer 43 and thus functions to hold the wires in the hinge assembly 40 even if the hinge assembly 40 is again rotated to the FIG. 9 position.
[0039] The hinge assembly 40 is then installed on the mobile terminal 20 . Referring to FIG. 10 , the base plate 42 is secured to the upper portion 24 of the housing 22 such that the opening through the hinge 40 aligns with the through-hole in the upper portion 24 . The pivot plate 44 is secured to the lower portion 26 of the housing 22 such that the opening through the hinge 40 aligns with the through-hole in the lower portion 26 . In one embodiment, the pivot plate 44 fits in a corresponding recess which may be provided on outer surface of the lower portion 26 of the housing 22 . When installed, the hinge assembly 40 allows the housing portions 24 , 26 to be relatively slidingly rotated between the closed position ( FIG. 11 ) and the open position ( FIG. 12 ). From the closed position, the housing portions 24 , 26 may be rotated in either direction to the open position. Depending on the direction of rotation, there may be some lost motion between the pivot plate 44 and the key ring 46 . When one of the tangs 72 engages the projection 76 on the key ring 46 , the pivot plate 44 and the key ring 46 rotate together until the projection 76 engages the detent 60 on the base plate, which is at the open position of the mobile terminal 20 . The key ring 46 and the detent 60 function as a stopper for restricting the range of rotation of the housing portions 24 , 26 to 180° in either direction. The cylindrical central opening through the spacer 43 prevents twisting of the wires or flexible circuit.
[0040] Although the present invention has been shown and described in considerable detail with respect to only a few exemplary embodiments thereof, it should be understood by those skilled in the art that we do not intend to limit the invention to the embodiments since various modifications, omissions and additions may be made to the disclosed embodiments without materially departing from the novel teachings and advantages of the invention, particularly in light of the foregoing teachings. For example, a hinge according to the present invention is suitable for use in a number of portable and non-portable electronics devices and applications. Accordingly, we intend to cover all such modifications, omission, additions and equivalents as may be included within the spirit and scope of the invention as defined by the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a crew may be equivalent structures. | A hinge for use in a mobile terminal comprises a first hinge portion defining an opening and having a slot extending from the periphery of the first hinge portion to the opening, and a second hinge portion defining an opening and having a slot extending from the periphery of the second hinge portion to the opening. The first hinge portion is one body portion of the mobile terminal, and the second hinge portion is secured to the other body portion. The hinge portions are rotatably connected such that the openings are aligned. The hinge portions are relatively rotatable between a first position where the slot in the first hinge portion and the slot in the second hinge portion are aligned, and a second position where the slot in the first hinge portion and the slot in the second hinge portion are not aligned and the openings cannot be accessed from the exterior of the hinge. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the process and the products obtained by a partial removal of carbon from coal ash which is used in the production of concrete. The carbon removed, through a thermal process of Partial Carbon Burn-Out (PCBO) can no longer reduce the activity of air entraining agents, which increase the stability, the number and the size of air voids in the concrete. The presence of appropriate air voids improves the freeze-thaw resistance of concrete.
2. Description of the Prior Art
Concrete consists of a cement binder, a pozzolanic material such as fly ash which will react with a mineral alkali, an aggregate material and sufficient water to cause the cement to set and bind the components into a hardened and durable material. A pozzolanic material reacts with calcium hydroxide, a by-product of Portland cement hydration to form compounds having the cementitious properties.
Unburned carbon in fly ash has a broad particle size distribution ranging from coarse char (>75 μm) to very fine soot sized (=40 nm) amorphous carbon particles that has a very high surface area (Gao, Y. M., H. S. Shim, R. H. Hurt, E. M. Suuberg, N. Yang, “Effects of Carbon on Air Entrainment in Fly Ash Concrete: Role of Soot and Carbon Black”, Energy & Fuels 11, 457, 1997). The very fine unburned carbon in fly ash has properties similar to that of activated carbon and as such has an affinity for molecules that have hydrophobic moieties, such as air entraining agents.
The durability of concrete to freeze-thaw cycles is dependent on its level of air entrainment. When water freezes its volume increases 9%. If concrete is fully saturated, all air voids are filled with water, the tensile stresses generated by the freezing water are sufficient to cause cracking and deterioration. Concrete has excellent strength in compression but its tensile strength is approximately 7%-10% of the compressive strength. When concrete begins to freeze the expanding ice forces water into the unfrozen regions of the cement binder—this movement of water creates large hydraulic pressures and generates tensile stress.
Many factors affect the durability of concrete to cycles of freezing and thawing: the cement binder content; amount and type of pozzolan; water to cement ratio; quality of the aggregates; and, the presence of air voids with an optimum spacing and size distribution.
Air is naturally entrapped in concrete through the folding and shearing action of mixing the cement paste. The entrapped air voids are large and not stable in concrete unless air entraining agents are used. Air entraining agents are surface active agents or surfactants. These agents reduce the surface tension of water, which tends to promote the fragmentation of large air voids into smaller ones, and to stabilize air voids by collecting at the water interface and forming a film.
The unburned carbon residue present in fly ash has a high adsorptive capacity for air entraining agents. The time dependent adsorption of air entraining agents causes a loss of entrained air during mixing and placement, and ultimately affects durability of the concrete by degrading the air void system.
LOI (Loss On Ignition) is a measure of the residual combustible material, primarily carbon in the coal ashes. There are several processes in commercial use that aim to reduce the LOI of moderate to high LOI fly ashes significantly to a level below 3% by weight. These include methods employing electrostatic separation or by carbon combustion. It should be noted that carbon makes up most of the measured LOI (to within about 10%) but more particularly it is the adsorption capacity of fly ash for air entraining agents and not the LOI, that is the ultimate criteria for whether the fly ash is commercially useful.
U.S. Pat. No. 5,399,194 describes a thermal treatment for fly ash in a fluid bed between 800 and 1300° F., or (426 and 700° C.) while U.S. Pat. No. 5,160,539 describes the use of a fluid bed to reduce the LOI in a temperature range from 1300 to 1800° F. or 700 to 982° C. and is clearly designed to eliminate as much carbon as possible.
SUMMARY OF THE INVENTION
One object of the invention is to provide a process for producing a coal ash having a low adsorption affinity for air entraining agents in concrete. This process comprising a partial combustion of a carbon residue of the feed coal ash wherein a fine carbon fraction of said carbon residue that is responsible for adsorption of air entraining agents in concrete is combusted, while leaving a non-combusted carbon fraction with a lower adsorption capacity for air entraining agents; and a recovery of the coal ash product.
It is another object of this invention to provide a method for inhibiting adsorption characteristics of coal ash bearing a carbon residue. The method comprising combusting an adsorbing fraction of said carbon residue responsible for adsorption of air entraining agents in concrete, while leaving non-adsorbing carbon of said carbon residue un-combusted in said coal ash.
Another object of the invention is a coal ash product which has low levels of a fine carbon fraction responsible for adsorbing air entraining agents in concrete. The fly ash product for use in concrete, is produced by a partial combustion of a carbon residue of a feed coal ash wherein the fine carbon fraction of said carbon residue responsible for adsorption of air entraining agents in concrete is combusted, while leaving a non-combusted carbon fraction of non-air entrainment agent absorbing carbon in the coal ash product.
Yet another object of the invention is a concrete product. The concrete product having a cement binder, an aggregate, and an air entraining agent characterized in that it includes, a coal ash product which has low levels of a fine carbon fraction responsible for adsorbing air entraining agents in concrete produced by, a partial combustion of a carbon residue of a coal ash wherein the fine carbon fraction of said carbon residue responsible for adsorption of air entraining agents in concrete is combusted, while leaving a non-combusted carbon fraction of non-air entrainment agent absorbing carbon in the coal ash product, which are all mixed together with water to produce said concrete product.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
When concrete contains sufficient cement (>225 kg/m 3 ) and the water to cement ratio is less than 0.55:1, the concrete will be durable providing that an air entraining agent is used to generate an air void system consisting of very fine bubbles (50 to 200 μm). The average distance from any point in the cement paste or the spacing factor, must not be more than 200 μm from the nearest air void in order to protect the cement paste. The air voids in air entrained concrete relieve the pressure (i.e. tensile stresses) by accommodating the hydraulic pressure produced by the expansion of water at lower temperatures and prevent damage to the concrete. Air entrained concrete that has adequate strength and is appropriately saturated with air will withstand hundreds of freezing and thawing cycles without dilating or losing strength.
Air entraining agents promote the adhesion of air voids to the surface of hydrating cement grains which further stabilizes the air void in the cement paste. In general, as the dosage of the air entraining agent increases, the air content increases up to a maximum value, after which additional increases in air entraining agent do not increase air content significantly. The dosage rate of air entraining agent required to achieve a target air content is dependent on the type of air entraining agent, concrete temperature, concrete materials, such as sand, cement, fly ash, and mixture proportions.
The adsorption of air entraining agents by the carbon contained in coal ashes, reduces their concentration in solution, which in turn causes the destabilization of air voids. Under such conditions air voids coalesce into larger voids, with some rising to the surface and being lost. The remaining fewer and coarser air voids are much less effective in protecting the concrete because of their low surface area.
Regardless of the actual mechanism of air entrainment, a certain concentration of air entraining agent is required to achieve an air content of 5% to 8% in concrete. Normal cement hydration absorbs a portion of the air entraining agent, which causes the air content of the concrete to decline with time.
There are various air entraining agents available and may contain a metal cation and an non-polar organic group. Typical air entraining agents include: neutralized Vinsol resin, sodium abietate, sodium oleate and sodium dodecylbenzene sulfonate.
The ASTM C618-01, test method for the “Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use as a Mineral Admixture in Concrete”, stipulates for both Class C and Class F fly ashes a maximum Loss-On-Ignition (LOI) of 6%. Experience has shown that with certain fly ashes, the entrainment and maintenance of an air void system is difficult and in some cases impossible, despite meeting the requirements of ASTM C618-01. Though Class C fly ashes have much less unburned carbon than Class F fly ashes they can also have difficulties entraining and maintaining an air void system. Class C fly ash is typically produced from lignite and sub-bituminous coal and contain higher quantities of lime (CaO), which in addition to having pozzolanic properties gives Class C fly ash cementitious properties as well. Class F fly ash is produced from the combustion of bituminous and anthracite coals, with far lower lime levels and little to no cementitious properties.
Unburned carbon in fly ash is either amorphous or crystalline, and the relative amounts of the two depend on the coal and combustion conditions in the boiler. Both types of carbon absorb air entraining agents but the amorphous carbon portion of the fly ash absorbs the air entraining agents, at a higher rate, dramatically reducing their concentration in solution. The very fine carbon in the ash has a high surface area and behaves like activated carbon and is responsible for adsorbing the air entraining agents. Coarse carbon has a lower surface area and adsorbs less of the air entraining agents.
The amorphous carbon has a higher surface area and is more polar relative to crystalline carbon (R. Hill, S. Sarkar, R. Rathbone, J Hower, Cement Concrete Research, Vol.27(2),pp 193-204, 1997). The fraction of amorphous carbon in fly ashes varies from source to source, and can vary within the same source. The ASTM C618-01 Loss-On-Ignition method does not provide information on the amount of amorphous carbon in fly ash and therefore alternative methods, such as the ASTM C311 mortar method or foam index are required to determine the air entraining agent adsorbing affinity of the fly ash. The method proposed here is a modified foam index method.
The foam index method was originally developed by Dodson and further modified by Menninger (R. Helmuth, “Fly Ash in Cement and Concrete”, Portland Cement Association, 1987, pp 80-81). The original method consists of adding 50 ml of water to 16 grams of Portland cement and 4 grams of fly ash (Class F) in a 125 ml glass jar. The mixture is shaken vigorously for 1 minute and then a diluted air entraining agent, such as neutralized Vinsol resin, is added drop-wise, in increments of 1 to 5 drops. After each addition of air entraining agent solution, the jar is shaken vigorously for 15 seconds. The foam layer is observed for stability over a period of 45 seconds and if no significant collapse of the foam occurs then the number of drops of air entraining agent solution used is the foam index value. The foam index value corresponds approximately to the apparent saturation point where most of the active adsorption sites on the fly ash carbon are covered with air entraining agent molecules. If the slurry is left to stand and shaken again the foam stability will decrease with time, indicating that equilibrium has not been reached. Therefore, it is important to obtain the foam index value at approximately the same time and to limit the amount of time allowed for the determination.
For the purposes of the invention the foam method has been modified and consists of the following steps: 5 grams of fly ash is added to 70 ml. of distilled water containing 0.3 ml. 25% sodium citrate solution; the suspension is titrated with a solution of 0.2% sodium lauryl sulfate (SLS) solution until a stable foam layer is obtained after shaking vigorously 20 times after each incremental addition of sodium lauryl sulfate solution; the volume of the titrated solution is the value taken for the foam index. A foam index value of 0.8 ml was found to be the average value for commercially saleable Class F fly ash and the target for Partial Carbon Burn-Out.
The modified foam index method was developed for use with Class F fly ash which has an LOI between 2% and 5%. ASTM C618-01 limits the LOI value to a maximum of 6% (12% if concrete data is available showing that air can be entrained and that this level has been accepted by the user), but in many cases it is difficult to achieve and maintain the specified air contents in concrete containing Class F fly ash that has an LOI greater than 3%. Class C fly ash has an LOI in the range of 0.1 to 1.5%+ and ordinarily do not exhibit problems with air entrainment. Nevertheless, significant changes in air entrainment and stability problems are occasionally experienced with many Class C fly ashes. The usual indicators of fly ash quality, such as color and LOI, do not provide sufficient information on the quality of Class C fly ashes. The foam index method, on the other hand, can detect such changes where the fly ash is not noticeably darker, the LOI is normal, but the foam index indicates a high adsorption capacity. The thermal treatment of this invention does not substantially change the color of the fly ash product.
EXAMPLE 1
Baseline values of foam index for raw fly ash samples from Hatfield, Fort Martin and Wateree are given in Table 1.
TABLE 1
Typical Foam Index Values for Marketable Fly Ash
Source -
Carbon
Modified Foam Index
Date Code
Content, %
0.2% SLS, mls
HFX00308
0.8
HFX91230
1.11
0.9-1.0
HFX91215
1.96
0.9
HFX91206-1
1.41
0.7
HFX91122
1.26
0.6
FMX91216
1.98
0.9
FMX00216
.83
0.6
FMX91207
1.73
0.7
Wateree
2.78
0.6-0.7
Notes:
5 ml used samples with the modified foam method described. HF and FM designate Hatfield and Fort Martin, respectively SLS = sodium lauryl sulfate
The fly ashes from Lakeview Power Plant in Ontario and Fort Martin in West Virginia, were considered and compared. Typically, fly ash has a particle size distribution such that approximately 75% of the mineral fraction is minus 45 μm, 45-50% is less than 20 μm, and about 25% is below 10 μm. Fly ashes from different sources are reasonably similar with some variations from source to source and as a function of how fine the coal was ground and the combustion process used.
The Lakeview and Fort Martin fly ashes show a total measured carbon content, with 5 and 10% of the carbon less than 10 μm and 20-25% minus 20 μm and 50% of the carbon is less than 45 μm.
With the surface area inversely proportional to diameter of the particle this in effect means that a greater percentage of surface area resides in the fine carbon fraction, this important property is linked to this invention.
The Partial Carbon Burn-Out trials were conducted using a pilot scale fluidized bed reactor and the fly ash from Pleasants W.Va. Initially, the fluidized bed reactor was operated at a temperature range of between 750 and 850° C. to determine the optimum operating temperature. The temperature obtained were measured immediately above the fluidized bed.
According to the results obtained in this program, thermal processing through the process of Partial Carbon Burn-Out (PCBO) with a pilot scale circulating fluid bed reactor was examined. PCBO was effective in reducing the adsorption capacity of the carbon in the fly ash. The fly ash product recovered after the partial carbon burn-out, experienced only an incomplete or interrupted combustion, as it still contained the majority of original carbon residue. This interruption is a distinct feature of the invention. The adsorption capacity of the carbon for air entraining agents was reduced by 55 to 70% in the temperature range of 700 to 850° C. This is an 11% reduction of LOI, from 4.05% to 3.58%.
Although the PCBO process of this invention was conducted in a compact circulating fluidized bed reactor, other solid and gas contactors can be foreseen. The solid and gas contactor may include specialized fluidized bed features alone or in combination that include circulation, classification and separation of solids, and with a bed such as a pacted bed, an expanded bed, a catalytic bed, a fixed bed alone and in combination.
The reduction in the adsorptive capacity of the carbon for air entraining agents is due to the destruction of the finer particles of carbon which with their smaller size and higher surface areas are eliminated first. As the carbon content decreases, the foam index falls more rapidly than expected. It may also be, that the reduction in the adsorptive capacity of the remaining carbon for air adsorbing agents is also affected by the modification through oxidation of the surface of the unburned carbon. Oxidation of the surface causes the formation of carboxylate or carbonyl species on the surface, which increases its polarity (negative). The greater negative charge reduces the affinity of the surface for air entraining agents, which is evidenced by the reduction in the foam index.
The results of Example 1 are presented in Table 2.
TABLE 2
Effects of PCBO on the Carbon, SO 3 Content and
Foam Index vs Above Bed Temperature ° C. [Pleasants Fly Ash]
Modified
Foam
Above
Index
Carbon
Bed
0.2%
% De-
Content
% De-
Sulfur
% De-
Temp. ° C.
SLS, ml
crease
%
crease
Content
crease
Feed
2.0
4.05
0.92
750
1.2
40
3.68
9
0.44
52
800
0.9
55
3.63
10
0.40
56
850
0.6
70
3.58
11
0.37
60
Approximately 10% of the total carbon in a the fly ash tested is responsible for 60 to 70% of the adsorption capacity exhibited by the fly ash for air entraining agents. This carbon fraction is very fine and also enriched with sulfur. A fly ash with a low affinity for air entraining agents can be consistently produced with the partial carbon burn out (PCBO) process, with a pilot scale fluidized bed reactor.
The sulfur in the unburned carbon originates from two sources;
unburned coal, which tends to be coarse; and
from the partially combusted and very fine carbon.
The authors propose that the fine carbon may adsorb and/or react with the SO 2 in the hot flue gases, which elevates the level of SO 3 in this carbon fraction. It is known that the adsorption capacity of activated carbon can be improved by the addition of sulfur compounds during the activation process. A similar phenomenon may also occur during the combustion of coal.
As the carbon is combusted by the PCBO process of this invention, there is a concomitant reduction in the sulfur content in the form of SO 3 . There is a non-linear relationship between the SO 3 content of the carbon and adsorption capacity.
Interestingly, there are circumstances where fly ash also contains unacceptable amounts of ammonia from air emission control mechanisms. A separate benefit of this invention is the case where the ammonia content in the ash from a NO x reduction treatment is high. Residual ammonia contamination of 600 ppm or higher can be significantly reduced by heat treatment at lower temperature, with a fluidized bed reactor and rendered benign. By raising the temperature of the ammonia containing fly ash to 450° C. the ammonia is reduced from 600 ppm to less than 40 ppm, well within acceptable limits for commercial use of the fly ash in concrete.
EXAMPLE 2
Fly ashes were treated in an extended run of the pilot scale fluidized bed reactor. These runs consisted of operating the fluidized bed reactor for 18 hour at 830° C. The results of these tests are given in Table 3. They indicate that the PCBO process consistently produces fly ash with low affinity to air entraining agents, as indicated by a low foam index value.
TABLE 3
Extended Run: 18 Hours at 830° C. (1526° F.)
[Pleasants fly ash]
Modified
Foam Index
0.2% SLS,
%
Carbon %
%
Sample ID
ml
Decrease
Weight %
Decrease
Comments
Feed
2.1
4.05
Very slow
end point
Sample #4
0.7
67
3.40
16
Fast end
point
Sample #5
0.7
67
3.38
16
Fast end
point
Sample #6
0.7
67
3.22
20
Fast end
point
Note:
samples #4, #5 and #6 represent last 6 hours of extended run. | Concrete's durability to freeze-thaw cycles is dependent on its level of air entrainment, the appropriate level of which is achieved with the aid of surface active or air entraining agents. These agents promote the fragmentation of large air voids into smaller ones and stabilize air voids in the concrete. The carbon matter found in fly ash when used as a pozzolanic component of concrete, adsorbs the air entraining agents, reduces the air voids and concrete's ability to withstand many freeze-thaw cycles. This invention teaches a process for a partial removal of the carbon from the coal ash, used in concrete, through a partial combustion of only a fine carbon fraction of the carbon residue of the coal ash responsible for adsorbing the air entraining agents, in a reactor with a controlled ignition system. The process of the invention thus limits the adsorption of the air entraining agents and improves the freeze-thaw properties of the concrete produced. | 8 |
This is a continuation of application Ser. No. 08/553,573, filed Nov. 27, 1995, now U.S. Pat. No. 5,807,518.
FIELD OF THE INVENTION
The present invention relates to a friction material designed for fitting to a device using friction in a liquid medium, and the method of producing such a friction material and the device to which it is fitted.
More particularly, such a friction material takes the form of a flat ring or a truncated cone and the device to which it is fitted is a clutch or brake disc, notably for an automatic gear box or associated therewith, operating in oil, or a synchronisation ring or cone for a manually-operated gearbox also operating in oil, such a device being installed in a vehicle.
BACKGROUND OF THE INVENTION
The friction materials used up to now for the aforementioned applications are of three types: materials of the paper type, sintered materials and graphite-containing moulded materials.
The materials of the paper type consist essentially of cellulose fibres impregnated with resin.
Such materials are obtained by a wet method using a normal paper-making process, that is to say by dispersing cellulose fibres in an aqueous solution containing a resin, then spinning and drying.
Such a method necessarily involves using short fibres, with an average length below one millimeter.
Materials of this type have the drawback of degrading very rapidly as soon as their temperature reaches 150° C., which is the case when the device that is equipped with the friction material must, within a small space, transmit or absorb high torques at speeds which, in practice, are growing ever higher.
This situation now arises by virtue of, on the one hand, the increasing power of thermal engines and, on the other hand, the reduction in the size of the devices for transmitting engine torque, which make it necessary to increase the gripping pressure of the friction devices.
Sintered materials do not exhibit the above described drawback but, unlike with materials of the paper type, the coefficients of friction obtained are low.
Moreover, these materials generate damaging vibrations and noises.
Materials of the graphite-containing moulded type have a relatively high cost price and do not permit stable transmission of a torque.
SUMMARY OF THE INVENTION
The aim of the invention is to overcome the aforementioned drawbacks by proposing a friction material for a liquid medium which has in particular a high, stable coefficient of friction, a high resistance to heating at high working pressures, and good resistance to wear.
A friction material for a liquid medium, according to the invention, is characterized in that it consists of a mat of fibres impregnated with a thermosetting resin, and in that the fibres have a length of at least 12 mm.
According to other characteristics taken separately or in combination:
the average length of the fibres is at most 120 mm;
the fibres are chosen from the group of fibres of glass, wool, cotton, ceramic, polyacrylonitrile, preoxidized polyacrylonitrile and aramid;
fillers in powder form are incorporated into the mat, comprising all or some of the following elements or compounds: copper, rockwool, carbon (coke and/or reduced-powder carbon fibres, graphite), zirconium silicate, iron sulphide, alumina, rubber and diatoms;
fillers in the form of pulps are incorporated into the mat, comprising all or some of the following compounds: pulps of glass, aramid, acrylic and phenolic fibres;
the resin of the thermosetting type includes a polar solvent, preferably aqueous;
the thermosetting resin has latex and/or fillers in powder form added to it which comprise all or some of the following elements or compounds: copper, rockwool, carbon (coke and/or reduced-powder carbon fibres, graphite), zirconium silicate, iron sulphide, alumina, rubber and diatoms.
The method of producing the friction material according to the invention is characterized by the following steps:
a) a mixture of fibres of the same nature or of different natures as defined above is produced in a mixer;
b) the mixture is carded to form a card web;
c) the card web is lapped;
d) the lap thus formed is needled;
e) the needled mat is impregnated with a thermosetting resin; and
f) the impregnated mat is dried.
According to other characteristics taken independently or in combination:
between steps b) and c) above, fillers in powder form as defined above are sprinkled on the card web;
before step e) the thermosetting resin has fillers as defined above added to it;
step e) is preceded by an operation of impregnation of the needled mat by means of a dilution or dispersion in a liquid of the fillers as defined above;
the carding is effected by means of a wool-type card;
the needling operation is preceded by a preliminary needling operation;
the resin impregnation is effected by soaking in a tank containing the resin in solution or dispersed in water; drying is preceded by a squeezing or hydroextraction operation;
after or during drying, the mat is wound up.
As a variant, the method is characterized by the following operations;
a) a mixture of fibres of the same nature or of different natures, as defined above, is produced in a mixer;
b) the mixture is carded to form a card web;
c') fillers in powder form as defined above, and a resin in powder form, are sprinkled on the card web;
d') the mat is pressed while being brought to an appropriate temperature to ensure the flow of the resin.
In order to produce a device coated with friction material, the method according to the invention is as follows:
g) a ring, or as a variant a plurality of sectors forming a ring, is cut out from the mat produced as indicated above;
i) the ring or plurality of sectors forming a ring is placed in the bottom of a mould;
j) a metal support is placed in the mould on the ring or on the plurality of sectors forming a ring;
k) where appropriate, a second ring or a plurality of sectors forming a ring is placed on the metal support, opposite the ring or the plurality of sectors forming a ring;
l) the mould is closed, shims being disposed so as to control and limit the movement of a piston closing the mould;
m) heating under pressure is effected in the mould, thereby also ensuring the adhesion of the ring, and where applicable of the second ring, to the metal support;
n) the mould is opened and the device covered with the friction material is cooled.
As a variant, step g) is replaced by a step h) identical thereto, but conducted between steps d) and e) above.
According to other characteristics of the invention, taken independently or in combination:
the mould and piston have a flat bottom;
the bottom of the mould is grooved;
the mould and the piston are in the shape of a truncated cone;
the shims limiting the movement of the piston are sized so that the porosity of the friction material is between 20% and 70%;
the heating temperature is between 130° C. and 220° C.
Other characteristics and advantages of the product and of the method will appear from a reading of the description that follows, of example embodiments and implementations of the invention, in relation to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
in FIG. 1 is a functional diagram of a first part of the installation designed for the implementation of the method according to the invention;
in FIG. 2 is a functional diagram of a second part of this installation;
in FIG. 3 is a diagram illustrating the cutting out of friction rings and sectors;
in FIG. 4 is a series of graphs summarizing the results of comparative tests.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Four fibre mats (examples A, B, C, D) are produced from the following compositions by weight of fibres:
FIBERS
EXAMPLES
A
B
C
D
GLASS
- Parts
20
—
20
—
COTTON
- Parts
—
30
—
—
CERAMIC
- Parts
10
10
10
—
PAN (polyacrylonitrile or
- Parts
10
—
10
20
preoxidized)
The average length of the fibres used is as follows:
glass fibres: 50 mm;
cotton fibres: 18 mm;
ceramic fibres: 12 mm;
PAN fibres: 42 mm.
Referring to FIG. 1, the above fibres or mixtures of fibres, produced in a mixer, are introduced into the hopper 1 of a feed device 2 for a wool-type card 3 which has a feed chute 4 .
In examples C and D, fillers in powder form are sprinkled at the discharge from the card 3 , on the card web formed, by means of a sprinkling device 5 .
The fillers in powder form have the following composition (composition by weight referred to the parts by weight of the above fibres):
EXAMPLES
Fillers IN POWDER FORM
A
B
C
D
COPPER
—
—
—
10
POWDERED ROCKWOOL
—
—
—
10
GRAPHITE
—
—
10
—
COKE
—
—
10
—
The card web is then lapped by means of a lapper 6 , and the lap thus formed undergoes a needling process in two phases: preliminary needling by a preliminary needler with rollers 7 and needling by a needler 8 .
The mat of needled nonwoven material thus produced is, in the example depicted, wound on a roll 9 at the discharge from the first part of the installation.
The roll 9 is carried into a second part of the installation shown in FIG. 2, and is paid out for the remainder of the process of producing a friction material.
As a variant (not shown), the second part of the installation follows immediately on from the first part and the needled nonwoven mat is not wound up.
The needled mat is fed into a cutting station 10 where rings 11 or sectors 12 as depicted in FIG. 3 or any other shape that the friction material is to take are cut out.
The part of the mat that is not cut out, also called a skeleton, is directed to a winder 13 , for subsequent recycling.
The cut-out shapes 11 or 12 are conveyed into an impregnating bath 14 containing one or more resins of the thermosetting type in solution or dispersed in water.
The impregnating bath 14 is of the following composition by weight, expressed in parts, in a manner consistent with the proportions indicated previously for fibres and fillers.
EXAMPLES
IMPREGNATING BATH
A
B
C
D
WATER-BASED RESIN
60
60
—
—
RESOL-BASED RESIN
—
—
40
60
In general, the following types of resin can be used:
phenolic plastic resins (resol or novolak);
aminoaldehyde resins (urea formaldehyde, melamine formaldehyde or combinations thereof);
epoxy (epoxide) resins;
polyimide resins.
At the end of impregnation, squeezing takes place, firstly in the bath (conveyor 16 ) and outside the bath (rollers 17 ).
As a variant, not shown, the cut-out shapes 11 , 12 undergo, after soaking in the impregnating bath, a hydroextraction operation.
The cut-out shapes 11 , 12 are then introduced into an infrared drying tunnel 18 , and then packaged.
As a variant, the operation of cutting out the shapes is carried out after impregnation, squeezing and/or hydroextraction and drying.
In the latter case, the impregnated mat can be wound up in order to be transported to a cutting station as shown in FIG. 3 .
Each cut-out shape, a ring or plurality of sectors forming a ring, is placed in a mould which has, depending on the equipment for which the friction material is intended, a bottom which is flat or in the form of a truncated cone or any other shape, grooved or otherwise.
A metal support is placed in the mould on the ring or plurality of sectors forming a ring.
Where appropriate, a second ring or a plurality of sectors forming a ring is placed on the metal support, opposite the ring or the plurality of sectors forming a ring.
The mould is closed, shims being disposed so as to control and limit the movement of a piston closing the mould.
Heating under pressure is effected in the mould, which moreover ensures the adhesion of the ring, and where applicable of the second ring, to the metal support.
The mould is opened and the device coated with the friction material is cooled.
Advantageously, the shims limiting the movement of the piston are sized so that the porosity of the friction material is between 20% and 70% and the heating temperature is between 130° C. and 220° C.
In order to effect comparative tests with a known friction material of the paper type, two samples of friction material (clutch disc) are produced with the following composition by weight:
cellulose fibres: 30% (length: 2 to 20 mm);
phenolic resin: 31%
diatoms: 23%
aramid fibres: 10% (length: 6 to 20 mm)
quartz: 5%
sodium sulphate: 1%
Four series of three clutch friction discs produced in accordance with the invention from the compositions of the above examples A, B, C and D and two series of three clutch friction discs of the paper type having the above compositions underwent endurance tests under the conditions indicated hereinafter.
Three discs from the same series, corresponding to the same embodiment, were placed in a testing machine of the type defined by the standard SAE II (US standard).
The test was effected in an oil bath brought to 114° C. A circulation of oil was also provided with a flow rate of between 2 and 3 liters per minute.
The test included three series of cycles.
Each cycle consisted of braking, until it stopped, a centrifugal mass previously launched at a rotation speed of 3600 revolutions per minute.
After each cycle the centrifugal mass was relaunched at the speed indicated above.
A 30 second time interval was provided between each cycle start.
The first series comprised 50 cycles where the unit-area pressure of the gripping of the discs was 0.5 Mpa, the inertia being 0.213 m 2 .kg.
The second series comprised 2400 cycles where the unit-area pressure of the gripping of the discs was 1.5 Mpa, the inertia being 0.501 m 2 .kg.
The third series was identical to the first.
The graphs in FIG. 4 represent the evolution of the dynamic friction coefficient of each of the six samples during the endurance cycles defined previously.
It will be observed that at between 500 and 800 cycles, a paper lining is destroyed while the friction material according to the invention remains intact after 2500 cycles (end of tests).
Furthermore, a remarkable stability will be observed in the coefficient of friction of the material according to the invention during the cycles, at a level very close to that of a paper-type material.
Variant embodiments can be used.
In particular, fillers in the form of pulps can be incorporated into the mat, notably pulps chosen from amongst the group of pulps of glass, aramid, acrylic and phenolic fibres.
It is, moreover, entirely possible to incorporate the fillers into the liquid resin instead of, or in addition to, sprinkling them onto the mat.
The fillers can also be diluted or dispersed in a suitable liquid constituting a first impregnating bath for the mat, a second impregnation then being provided so as to ensure the addition of resin.
Furthermore, it is possible to use a solid resin, in the form of a powder, which is sprinkled onto the mat at the same time as the fillers. This mat is then pressed to the correct thickness at 60° C. for 2 secs; in this variant, there is no needling or impregnation. | A friction material for a liquid medium, according to the invention, consists of a fibre mat impregnated with a thermosetting resin, the fibres having a length of at least 12 mm. The method of producing such a material includes the following steps:
a) a mixture of fibres of the same nature or of different natures is produced in a mixer;
b) the mixture is carded to form a card web;
c) the card web is lapped;
d) the lap thus formed is needled;
e) the needled mat is impregnated with a thermosetting resin. | 3 |
TECHNICAL FIELD
The present invention relates to a dual type constant velocity universal joint which is formed by integrating two pieces of constant velocity universal joints and which is mainly used for a drive axle of a vehicle. In particular, the present invention relates to a dual type constant velocity universal joint which is preferable for use as a constant velocity universal joint for a drive axle of a rough-terrain crane vehicle, farm tractor or the like that requires a large steering angle.
BACKGROUND ART
Conventionally, in many drive axles for farm tractors or the like that require a large steering angle, the differential gear output shaft is coupled to the wheels via a constant-velocity type double Cardan joint. While a double Cardan joint requires a long axial length and a large outer diameter, it can have an intersection angle exceeding 50°. The constant-velocity type double Cardan joint is ordinarily lubricated by grease that has been filled in an axle housing. In the meantime, a drive axle of a large vehicle such as a rough-terrain crane vehicle adapted to on-road driving uses one constant velocity universal joint of Rzeppa-type or ball-fixed type (hereinafter sometimes referred to as “BJ” or “BJ-type”) with bellows boot to simplify the mechanism (see Patent Document 1). The BJ type includes an outer ring on which a curved track groove is formed in an axial direction on a spherical inner diameter surface, an inner ring on which a curved track groove is formed in an axial direction on a spherical outer diameter surface, a plurality of balls for torque transmission disposed in ball tracks that are formed through coordination between the track groove of the outer ring and the track groove of the inner ring corresponding thereto, and a cage provided with pockets for holding the balls.
When a constant velocity universal joint of BJ-type is used for a drive shaft, an axle section (driven shaft) that integrally extends from one end of the outer ring in an axial direction is coupled to a wheel bearing, and a shaft (drive shaft) that is spline engaged with a shaft hole of the inner ring is coupled to a slide-type constant velocity universal joint. When there is an angular displacement between the two axes, that is, between an axle section of the outer ring and a shaft of the inner ring, the balls housed in the pockets of the cage are always held in an angle bisecting plane of any operating angle, whereby constant velocity of the joint can be maintained. The operating angle herein refers to an angle created by the axle section of the outer ring and the shaft of the inner ring.
In the meantime, a drive axle of a large vehicle such as a rough-terrain crane vehicle includes, in a section inside of the wheel hub, a so-called hub reduction including a reducer such as a planetary gear mechanism to prevent large drive torque from acting on the BJ-type constant velocity universal joint.
Patent Document 1: Japanese Patent Laid-open Publication No. Heisei 4-358970
DISCLOSURE OF THE INVENTION
Problems to be Solved by the Invention
The drive axle including a BJ with a bellows boot must allow a large angle exceeding 30° when steering the wheels. Accordingly, such a drive axle has a longer axial direction length of the boot and a larger outer diameter than an ordinary drive axle. In the case of a rough-terrain crane vehicle including a hub reduction, the number of revolutions when the vehicle is driving straight at a high speed exceeds 1300 rpm. A synergetic effect of the high speed revolution and the large diameter of the BJ causes a problem that the boot swells and is deformed. To address this, although improvement is being made mainly on the shape of the bellows boot and on the material thereof to increase hardness of the bellows boot, such improvement is not enough to inhibit deformation of the boot. There are increasing cases where the problem of deformation of the boot cannot be solved merely by improvement of the shape and material of the bellows boot because of the relationship between the required BJ size and the number of revolutions.
In addition, in the case of a drive axle using one BJ, when excessive torque caused by sudden start or the like acts thereon in the case where the operating angle of the BJ has increased, damage can occur at a portion where the ball guiding groove is shallow. In other words, when the operating angle of the BJ has increased, the ball moves to the rear side of the ball guiding groove. The rear side of the ball guiding groove has a smaller groove depth. Accordingly, a contact ellipse of the ball in the ball guiding groove pushes out an edge of an edge chamfer of the ball guiding groove. When a large load accompanying excessive torque acts on the ball under this state, the outer spherical surface of the inner ring in the vicinity of the ball guiding groove rises and thus it is deformed. When the outer spherical surface of the inner ring is deformed, operability of the joint may sometimes be reduced or a chamfer edge of the ball guiding groove may be chipped. To prevent such damage, the outer diameter of the BJ must be increased.
Furthermore, there is a structural restriction in a drive axle using one BJ also that a king pin center, which is the center of steering rotation of the wheel, must match the center of the angled bending of the BJ (that is, the intersection of the 2 axes; the axle section of the outer ring and the shaft of the inner ring).
An object of the present invention is to provide a constant velocity universal joint which can inhibit deformation of a boot at a high speed revolution, which can have an operating angle exceeding 50° without increasing the size of the outer diameter size of the BJ, and which does not require precise position alignment with a king pin center.
Means for Solving the Problems
To solve the foregoing problem, the present invention includes two constant velocity universal joints. Each constant velocity universal joint includes: a cylindrical outer ring in which a plurality of guiding grooves that extend in an axial direction are formed on a spherical inner circumferential surface; an inner ring in which a plurality of guiding grooves that extend in an axial direction are formed on a spherical outer circumferential surface; balls for torque transmission each of which is disposed in each of a plurality of ball tracks which are formed through coordination between the guiding grooves of the outer ring and the guiding grooves of the inner ring; and a cage for holding the balls. The outer rings are coaxially integrated with back to back, and a portion between the outer circumferential surface on the opening side of the outer ring and a shaft connected to the inner ring is covered with a boot having a metal ring.
The dual type constant velocity universal joint according to the present invention uses a boot having a metal ring (of diaphragm type) in place of a conventional bellows boot. Therefore, the problem of deformation of the boot when rotating at a high speed can be resolved. Specifically, in the case where the reference axis diameter of the shaft to be coupled to the inner ring of the BJ is 2 inches, the maximum number of revolutions of a conventional bellows boot at the operating angle 0° would be approx. 1300 rpm. However, no problem of deformation will occur in the BJ according to the present invention which uses a boot having a metal ring, even when the number of revolutions is 2000 rpm or higher.
In addition, since the dual type constant velocity universal joint according to the present invention includes two BJs, the dual type constant velocity universal joint as a whole can actualize twice as large as the operating angle of one BJ. Specifically, tightening of two BJs of a compact disc type in an axial direction by a bolt enables reduction of the operating angle per BJ to 18° or less. As a result of this, even at an operating angle at which a part of a contact ellipse of the ball would push out the chamfer of the guiding grooves of the inner ring in a conventional joint, deformation of the chamfer of the guiding groove caused by load torque can be prevented without increasing the size of the outer diameter of the BJ.
To coaxially integrate the outer rings back to back, for example, a disk-shaped adapter flange having a center through-hole is sandwiched between two outer rings and a bolt is inserted in the two outer rings and the adapter flange to integrate them. Alternatively, two outer rings may be formed on opposite sides of a cylindrical component which has been integrated.
Advantage of the Invention
As described above, by integrating two constant velocity universal joints, the present invention can actualize an operating angle or an intersection angle that is twice as large as the dual type constant velocity universal joint as a whole. For example, in the case where the operating angle or the intersection angle for one constant velocity universal joint is 35°, the intersection angle which is twice as large as it, that is 70°, can be actualized as a whole. As a result of this, the operating angle is approximately half of the case where one constant velocity universal joint is used. In addition, deformation of the guiding grooves because the contact ellipse thereof has pushed out is also more advantageously prevented, whereby the size reduction of the constant velocity universal joint can be achieved.
In addition, adoption of a boot having a metal ring can inhibit formation of a boot when rotating at a high speed. Accordingly, the dual type constant velocity universal joint is preferable for a drive axle of a rough-terrain crane vehicle mounted with a hub reduction.
Use of two constant velocity universal joints eliminates the necessity of precise position alignment of the king pin center, which is the steering center of the wheel, with the bending center of the joint. Therefore, freedom in the design of a drive axle increases.
Use of a disc-type constant velocity universal joint and of a boot having a metal ring enables a compact joint which is short in an axial direction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal sectional view of a dual type constant velocity universal joint according to a first embodiment of the present invention in the state where the operating angle is 0°;
FIG. 2 is a longitudinal sectional view of the state where the joint has become close to the maximum operating angle;
FIG. 3 is a longitudinal sectional view of a dual type constant velocity universal joint according to a second embodiment of the present invention in the state where the operating angle is 0°;
FIG. 4 is a longitudinal sectional view of the case where one of the joints has the operating angle of 32°; and
FIG. 5 is a cross sectional view showing a surface pressure in the guiding groove of the inner ring.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be hereinafter described with reference to FIGS. 1 to 5 . FIGS. 1 and 2 show a first embodiment of a dual type constant velocity universal joint according to the present invention. FIG. 1 shows the state where the operating angle is 0°, and FIG. 2 shows the state where the operating angle is 32°. The dual type constant velocity universal joint has a structure formed by integrating two ordinary fixed-type constant velocity universal joints of same specifications. The constant velocity universal joint uses balls 4 as torque transmission component. A differential gear-side shaft 3 is connected to one of the joints, and a wheels-side shaft 10 is connected to the other joint. A distal end of the wheels-side shaft 10 is connected to a sun gear of a hub reduction. A slinger 9 is attached to the wheels-side shaft 10 . The outer diameter surface of the slinger 9 makes contact with a lip section of an oil seal for preventing leakage of lubricant from a planetary gear of the hub reduction.
For the sake of convenience, the embodiment will now be described with reference to mainly a one-side half of one side half the dual type constant velocity universal joint, that is, one of the two constant velocity universal joints. The one-side half of the dual type constant velocity universal joint, as shown in FIG. 2 , includes a cylindrical outer ring 1 , an inner ring 2 , the shaft 3 , the balls 4 for torque transmission, a cage 5 and a boot 8 . In the cylindrical outer ring 1 , six curved guiding grooves 1 b are formed in an axial direction on an inner diameter spherical surface 1 a thereof. In the inner ring 2 , six curved guiding grooves 2 b are formed in an axial direction on an outer diameter spherical surface 2 a thereof. The inner ring 2 includes a spline (or serration) hole 2 c . One end of the shaft 3 is engaged with the spline hole 2 c . Each of the balls 4 for torque transmission is disposed in each of 6 ball tracks that are formed through coordination between the guiding grooves 1 b of the outer ring 1 and the guiding grooves 2 b of the inner ring 2 . The cage 5 holds the balls 4 . The boot 8 is disposed between the outer circumferential surface on the opening side of the outer ring 1 and the outer circumferential surface of the shaft 3 ( 10 ). Although both the numbers of the guiding grooves 1 b , and of the guiding grooves 2 b are herein set as 6, they may sometimes be increased to 7, 8, 9, 10, or any preferable number.
The outer ring 1 has a structure formed by integrating the individual outer rings 1 of the two constant velocity universal joints. Specifically, the two outer rings 1 are coaxially integrated in the state where they are matched back to back with the opening sides thereof (on the shafts 3 , 10 side) facing outwards. The insides of the right and left outer rings 1 are connected with each other. The term “integrated” herein includes both the case of connecting two outer rings 1 that have been made as separate bodies to integrate them (in the first embodiment) and the case of complete integral molding from a common material (in the second embodiment). In the first embodiment, the two outer rings 1 are integrated with the adapter flange 11 being sandwiched therebetween. When the dual type constant velocity universal joint is used for a drive axle, the center in the width direction of the adapter flange 11 substantially matches an axis of rotation of the king pin.
The adapter flange 11 is a disk-shaped component which has a center through-hole 11 a . Cylinder sections for position alignment 11 b , 11 b are formed in the peripheral part of the adapter flange 11 such that they project leftwards and rightwards. The size of the cylinder sections 11 b , 11 b is matched with that of the outer diameter of the outer ring. Bolt insertion holes 11 c are formed at a plurality of locations in circumferential direction in a section inside of the cylinder section 11 b . The peripheral part of the outer ring at a portion where the ball guiding grooves 1 b are located is thinner, and the bolt insertion holes 11 c are formed at a portion excluding such thin portion, that is, at a plurality of locations at equal intervals in circumferential direction between the guiding grooves. After the positions of the bolt insertion holes 11 c are aligned a bolt 12 is inserted thereinto, and a nut 13 is screwed into the distal end of the bolt 12 . Numerals 14 , 15 denote spring washers.
The outer circumferential surface of the outer ring 1 is a cylindrical surface 11 d around the axis line of the outer ring 1 as the center. A metal ring 16 of the boot 8 is engaged with the cylindrical surface 11 d on the opening side. The metal ring 16 includes bolt insertion ports 16 a at equal intervals in circumferential direction, and the metal ring 16 is tightened to the side surface of the outer ring 1 by the bolt 12 when the two outer rings 1 , 1 are connected to the adapter flange 11 by the same bolt 12 . The metal ring 16 includes a large diameter section 16 b , a flange section 16 c and a small diameter section 16 d . The large diameter section 16 b is engaged with the outer circumferential surface of the outer ring 1 . The flange section 16 c abuts with the side surface of the outer ring 1 . The small diameter section 16 d projects in the direction to be separated from the outer ring 1 . A liquid packing is interposed between the flange section 16 c and the side surface of the outer ring 1 for preventing leakage of grease enclosed in the interior of the joint. A large diameter end 8 a of the disk-shaped boot 8 is integrated through vulcanization with the small diameter section 16 d of the metal ring 16 . A small diameter end 8 b of the disk-shaped boot is engaged with a ring-shaped concave section 3 a ( 10 a ) that is formed on the outer circumferential surface of the shaft 3 ( 10 ). A band 17 is fixed to the outer circumferential surface of the small diameter end 8 b . The disk-shaped boot 8 has a structure, with a U-shaped cross section, in which the large diameter end 8 a and the small diameter end 8 b are opposite to each other in radial direction.
The distal end of the shaft 3 is engaged with the spline hole 2 c of the inner ring 2 . At the same time, relative movement of the shaft 3 with the inner ring 2 is restricted by a rectangular circlip 19 and a round circlip 18 that are engaged with the ring-shaped grooves 3 c , 3 b , respectively. A center hole 3 d ( 10 d ) is formed on the distal end surface of the shaft 3 ( 10 ) for centering when lathing the shaft 3 ( 10 ).
Each of the right and left the constant velocity universal joints has a structure which is called as Rzeppa type, ball-fixed type, or double-offset type as a single unit. In the state where the operating angle is 0° as shown in FIG. 1 , the respective centers O 1 , O 2 with radials R 1 , R 2 of the guiding grooves 1 b , 2 b of the outer ring 1 and the inner ring 2 are offset with respect to the common center O (that is, the center of the joint) of the inner diameter spherical surface 1 a of the outer ring 1 and of the outer diameter spherical surface 2 a of the inner ring 2 in opposite axial directions by an equal distance f. As a result of this, the ball track that is formed through coordination between the guiding grooves 1 b and the guiding grooves 2 b corresponding thereto has a wedge shape that is opened toward the opening side of the joint.
The cage 5 is formed of an annular component. The outer circumferential surface thereof is referred to as an outer diameter spherical surface 5 a that makes a sliding contact with the inner diameter spherical surface 1 a of the outer ring 1 , and the inner circumferential surface thereof is referred to as an inner diameter spherical surface 5 b that makes a sliding contact with the outer diameter spherical surface 2 a of the inner ring 2 . Windows 6 are formed through penetration by grinding, milling or the like on the peripheral wall of the cage 5 . The number of the windows 6 is the same as the number of the balls 4 . The windows 6 , which are for example rectangular, are formed at equal intervals in circumferential direction of the cage 5 .
The dual type constant velocity universal joint according to the present invention is configured as described above. In the state where the outer ring 1 and the inner ring 2 creates the operating angle 0° as shown in FIG. 1 , the ball 4 is held in a plane which includes the center O of the joint and which is perpendicular to the rotational axis line due to the offset effect of respective curvature centers O 1 , O 2 of the guiding groove 1 b of the outer ring 1 and of the guiding groove 2 b of the inner ring 2 , respectively, and torque is transmitted in this state.
Next, in the state where the outer ring 1 and the inner ring 2 at the opposite sides of the dual type constant velocity universal joint are bent to the limit operating angle θ, the dual type constant velocity universal joint as a whole actualizes the operating angle 2θ. The torque transmission balls 4 of each joint are aligned in the plane that bisects the angle θ by the cage 5 , which ensures maintaining constant velocity of both joints.
In the case where the dual type constant velocity universal joint is used for a drive axle, the center in the width direction the adapter flange is substantially positioned at the rotational center of the king pin as described above. However, the joint of the present invention is a dual type constant velocity universal joint that is formed by connecting two BJs. Accordingly, unlike a conventional joint using only one BJ, there is no need for precise position alignment with the axis rotation of the king pin.
FIG. 3 shows a second embodiment of the present invention, in which an outer ring 1 ′ is of an integrated type and the adapter flange 11 as described before has been omitted. In other words, two outer rings are formed on opposite sides of an integrated cylindrical component. The metal ring 16 of the boot 8 is fixed to the side surface of the outer ring 1 ′ by a hexagonal socket bolt 20 . Other elements are the same as those in the first embodiment. Therefore, the same numerals are provided to portions corresponding to the portions in FIG. 1 and FIG. 2 , and the description thereof will be omitted. In the meantime, the state in the case where one of the BJs of the second embodiment has the operating angle 32° is shown in FIG. 4 . In this state, a disadvantageous situation is generated in which the ball 4 at the rear side of the joint moves to a shallow portion at the rear of the guiding groove 1 b , thereby the guiding groove 1 b being easily deformed.
The surface pressure at a ball contact point in the guiding groove 2 b of the inner ring 2 will now be described. FIG. 5 slightly exaggeratedly shows the relationship between a contact ellipse 21 and a ball contact point surface pressure curve P ball . The resultant force of the ball contact point surface pressures is expressed as P. The relationship of force relationship shown in FIG. 5 is common to the first embodiment as described above and the second embodiment. With respect to the ball 4 expressed commonly, the outer diameter spherical surface 2 a of the inner ring 2 when the operating angle is 0° is expressed in by the solid line. Meanwhile, the outer diameter spherical surface 2 a when the operating angle of a conventional joint using one BJ is 32° is expressed by the dashed line. It is the relationship between the ball 4 at the rear side of the joint and the guiding groove 1 b in FIG. 4 that the dotted line indicates.
The outer diameter spherical surface 2 a when the operating angle 32° of the joint of the present invention is shown by the dashed-dotted line. In the case where a conventional joint has the operating angle 32°, a shoulder section of the contact ellipse 21 of the ball 4 pushes out a chamfer 22 of the guiding groove 2 b . As a result of this, a large load in accordance with excessive torque acts on the ball 4 , whereby an edge load 23 causes the outer diameter spherical surface 2 a of the inner ring in the vicinity of the ball guiding groove 2 b to rise to deform. Such deformation of the outer diameter spherical surface 2 a of the inner ring may cause reduced operability of the joint or cause chipping of the edge of the chamfer 22 of the ball guiding groove 2 b . According to the dual type constant velocity universal joint of the present invention, since the joint uses two BJs, each BJ requires only half of the operating angle the dual type constant velocity universal joint requires as a whole. Therefore, even when the same operating angle 32° is granted, the outer diameter spherical surface 2 a of the inner ring 2 is located at the position as shown by the dashed-dotted line, and accordingly, there is a leeway in the depth of the guiding groove 2 b . Therefore, substantially no edge load is generated, which can suppress deformation caused by rising of the outer diameter spherical surface 2 a of the inner ring.
Although the embodiments of the present invention have been so far described, the present invention is not limited to the above-described embodiments, and various modifications can be made based on the technical idea as described in the scope of the claims.
INDUSTRIAL APPLICABILITY
A dual type constant velocity universal joint of the present invention is not limited to use in drive axles of rough-terrain crane vehicles or farm tractors. It can also be applicable to drive axles of various vehicles and to industrial machines that require high operating angles. | A dual type constant velocity universal joint solves the problems of greasing work efficiency and lubricating ability of a double Cardan Joint. The dual type constant velocity universal joint includes two constant velocity universal joints. Each constant velocity universal joint includes: a cylindrical outer ring in which a plurality of guiding grooves that extend in an axial direction are formed on a spherical inner circumferential surface; an inner ring in which a plurality of guiding grooves that extend in an axial direction are formed on a spherical outer circumferential surface; balls for torque transmission each of which is disposed in each of a plurality of ball tracks which are through coordination between the guiding grooves of the outer ring and the guiding grooves of the inner ring; and a cage 5 for holding the balls. The outer ring are coaxially integrated with back to back, and a place between the outer circumferential surface on the opening side of the outer ring and shafts connected to the inner ring is covered with a boot having a metal ring. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to a device and method for detecting Helicobacter Pylori in human subjects.
BACKGROUND OF THE INVENTION
[0002] It has been known for some time that infection by Helicobacter pylori ( H pylori ) may increase the risk of a subject suffering from illnesses such as gastritis and duodenitis, and from peptic and duodenal ulcers, Detection of H pylori is therefore desirable to determine whether patients have, or have increased risk of having, such illnesses, and to enable appropriate treatment to be given.
[0003] [0003] H pylori produces ammonia and carbon dioxide by the action of a urease on urea in bodily fluids, and various tests have been proposed to detect H pylori by detecting the products of this reaction.
[0004] A test which is currently in use involves administering 13 C-labelled urea to the subject and subsequently testing carbon dioxide in the subject's breath for the presence of 13 C. However, testing for 13 C requires a sample to be sent away for laboratory testing, which is slow and relatively expensive.
[0005] Various methods are known for diagnosing the presence of H pylori in human subjects. In U.S. Pat. No. 4,947,861 it was proposed to detect the presence of ammonia in a subject's breath following oral administration of urea. The method comprises collecting a sample of alveolar air at least ten minutes after administration of the urea, passing the air over an alkaline hygroscopic material to remove water vapour, and passing the dried alveolar air to a sensor which indicates the presence of amonia. The sensor described is a glass tube filled with a granular material that changes colour as ammonia is passed through it. DE 299 02 593 U1 describes the use of an electronic “nose” for detecting infection by H pylori, and other conditions such as lactose intolerance, enzyme shortages, bacterial or viral infections. The electronic nose produces a fingerprint which is compared with a stored databank to produce a diagnosis. U.S. Pat. No. 5,719,052 describes a method and apparatus for collecting gas from a subject's stomach by stimulating the subject's vomiting reflex.
[0006] International Patent Application WO 97/3035 describes various chemical indicators which change colour in the presence of ammonia to provide a visible indicator of ammonia in a subject's breath.
[0007] It is desirable to have a detection device and method for detecting H pylori which is non-invasive, speedy, and which can be used by a patient or other person without medical supervision.
SUMMARY OF THE INVENTION
[0008] According to a first aspect of the present invention there is provided a method for detecting the presence of Helicobacter pylori in the gastroenteral tract of a subject, the method comprising the steps of
[0009] a) obtaining a volume of gas from the lungs and/or stomach of the subject;
[0010] b) dividing the said volume of gas into first and second substantially equal portions;
[0011] c) causing or permitting the first said portion of gas to come into intimate contact with a first electronic or electrochemical ammonia sensor connected to means for measuring the electrical resistance of the said first sensor;
[0012] d) causing or permitting the second said portion of gas to come into intimate contact with ammonia absorbing means rand then into intimate contact with a second electronic or electrochemical ammonia sensor connected to means for measuring the electrical resistance of the said second sensor;
[0013] e) measuring the resistance of the first and second sensors when in contact with the said portions of gas;
[0014] f) comparing the said resistances of the sensors to produce a compared value; and
[0015] g) producing a visible output signal to indicate a positive or negative diagnosis of Helicobacter pylori infection according to whether or not the compared value exceeds a predetermined threshold value.
[0016] The method is non-invasive, and it can be speedy and easy for a patient or other subject to salt-administer. It is not necessary to administer urea to the subject prior to carrying out the method.
[0017] An antacid (for example magnesium hydroxide) may be administered orally prior to testing, This will promote conversion of ammonium ions in the stomach to gaseous ammonia. If the antacid is a carbonate or bicarbonate (for example sodium bicarbonate), it will also produce carbon dioxide to facilitate eructation.
[0018] A pair of similar sensors are provided, each in its own chamber. The gas is distributed substantially equally between the two chambers, but one chamber has an ammonia-absorbing barrier through which gas passes before coming into contact with the sensor. Electronics means compare the difference between or ratio of resistances of the two sensors and express the result as a visible output. The output could be numeric, but is preferably in the form of a signal corresponding to either a positive or a negative diagnosis. For example, a green light or a red light could be illuminated.
[0019] To further increase the sensitivity of the device, the gas could be passed through an alkaline desiccant (for example solid sodium hydroxide) in known manner, to remove water vapour (and some carbon dioxide) before the gas enters the chambers.
[0020] A preferred sensor comprises a film of polypyrrole, which is connected by electrodes to a suitable meter. Methods of making polypyrrole films suitable for use in the invention are described in GB 2 234 515 and EP 0 206 133. The film preferably has a thickness in the range 50 to 250 μm.
[0021] According to another aspect of the present invention there is provided a detection device for measuring ammonia content in gas from a subject's lungs and/or stomach, the device comprising:
[0022] a) a first chamber and a second chamber, each of which has an entrance opening for receiving the said gas, and each of which houses an electronic or electrochemical ammonia sensor connected to means for measuring the electrical resistance of the sensor;
[0023] b) the entrance openings of the chambers being connected to an inlet, the arrangement being such that incoming gas from the inlet will be divided into two substantially equal portions, each of which will pass through a corresponding entrance opening;
[0024] c) means for comparing the resistance of both sensors to produce a compared value;
[0025] d) means for producing a visible output signal according to whether the compared value exceeds a predetermined threshold value; and
[0026] e) wherein the second chamber is provided with means for absorbing ammonia, located between the entrance opening thereto and the sensor therein whereby at least some gas which enters the second chamber through the entrance opening will pass through the ammonia-absorbing means
[0027] Although the term “ammonia-absorbing means” is used herein for convenience, it will be understood that this term includes any means which remove ammonia from the gas. Thus, the term includes amonia adsorbents and materials which chemically combine with ammonia.
[0028] A preferred ammonia sensor comprises a film of polypyrrole, connected by electrodes to a suitable meter.
[0029] In a preferred embodiment, each chamber is provided with an exit vent to facilitate the passage of gas therethrough.
[0030] To reduce the volume of “dead space” in the chambers, they may optionally be constructed to be expandable, for example by having elastic walls, by being of telescopic construction, or by having a movable plunger, like a syringe. By reducing dead space, and therefore dilution of the gas portions, the sensitivity of the method can be increased.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] The invention will now be further described, by way of example, with reference to the following drawings in which:
[0032] [0032]FIG. 1 is a schematic representation of one chamber of an amonia detection device in accordance with an aspect of the present invention;
[0033] [0033]FIG. 2 is a graph showing change in resistance of the device of FIG. 1, for different subjects;
[0034] [0034]FIG. 3 is a graph of response against time for the device of FIG. 1;
[0035] [0035]FIG. 4 is a schematic representation of an ammonia detection device in accordance with the present invention; and
[0036] [0036]FIG. 5 shows changes in electrical resistance measurement results for subjects under a defined test protocol.
DETAILED DESCRIPTION
[0037] The experimental device for detecting gaseous ammonia shown in FIG. 1 comprises a chamber 2 in which is housed an ammonia sensor 4 , The sensor 4 comprises a polypyrrole film 16 , about 50 μm thick, which changes its electrical resistance in the presence of ammonia. The film 16 is carried on a pcb-type conductive board, for example Veroboard™, which has been etched to remove conductive material completely across the middle of the sensor 4 , so that the two ends 18 of the board are not in electrical contact with each other. An insulating film of PEEK is disposed between the film 16 and the conductive board. The film 16 is in electrical contact at opposed edges with each conductive end portion 18 The end portions 18 are each connected by wires 14 to a meter 6 which measures electrical resistance across the film 16 . In practice, a corresponding chamber will be provided, illustrated in FIG. 4, which is of similar construction but which includes an ammonia-absorbing material. This provides a corrected baseline value.
[0038] The inside of the chamber 2 is maintained at 100% humidity and sealed by clingfilm, in this example Nescofilm™. When the device is used in the method of the invention, a sample of gas 24 from a subject's lungs and/or stomach is collected in a syringe B and introduced into the chamber 2 via a needle 10 . The meter 6 records the electrical resistance of the polypyrrole film 16 before the gas 24 is introduced into the chamber 2 , and again after the gas has been introduced. The meter 6 then compares the resistances to produce a compared value and lights up an LED 20 or 22 according to whether the compared value is above or below a predetermined threshold. The meter 6 may measure the difference in resistance, or a ratio of resistances. The threshold value is calibrated to be just below the value produced by samples from test subjects known to be infected with H pylori. If the LED 22 lights up, showing a value which corresponds to infection, the subject knows to seek appropriate treatment or confirmatory alternative testing.
[0039] [0039]FIG. 2 shows test results for two groups of control subjects, one group known to be H pylori negative and the other H pylori positive. In each case, a 10 ml sample of gas 24 was collected and introduced into a chamber of about 10 to 15 ml volume. The film 16 was 10 mm square. The two sets of results on the left are for a breath test only, and the two sets of results on the right (the ‘belch test’) are for gas collected from subjects' stomachs, following ingestion of sodium bicarbonate in water. In each case, there is a clear threshold between the measured resistance for the negative and positive groups.
[0040] The same test conditions were used to check the response of sensors over time, but using a known concentration (100 ppm) of ammonia in air. The sensors were maintained at 100% humidity. The results are shown in FIG. 3, with percentage change in resistance being plotted against the time (days) in which the sensor 4 was maintained in the chamber 2 prior to the measurement being taken. For all times up to 60 days, the percentage change was at least 15%.
[0041] The device shown in FIG. 4 comprises a first chamber 2 a housing a first sensor 16 a, and a second chamber 2 b housing a second sensor 16 b. The chambers 2 a and 2 b are formed from an inner tubular member 34 and an outer tubular member 36 with a gas-tight seal 38 therebetween Because the tubular members 34 , 36 are telescopically nested together, the chambers 2 can expand as gas is introduced into them, thereby reducing dead space. The chambers 2 and sensors 16 are of identical shape and construction. The first chamber has an entrance opening which is substantially occupied by a first porous frit 28 , and the second chamber has an entrance opening which is substantially occupied by a second porous frit 30 . The frits 28 , 30 are arranged and composed such that each provides substantially the same resistance to the passage of gas 24 which is provided through a common entrance opening 32 , for example by a subject breathing through that entrance. Each chamber may optionally be provided with a vent opening ( 40 ) to facilitate the flow of gas through the chambers. The second frit 30 is provided with means for absorbing ammonia, for example sodium dihydrogen phosphate or copper sulphate crystals, so that at least some of the ammonia (and preferably substantially all of the ammonia) which may be present in gas 24 blown into the second chamber 2 b is absorbed in the second frit 30 and does not reach the second sensor 16 b. The first frit 29 does not significantly absorb ammonia, so that ammonia which is present in gas 24 blown into the first chamber 2 a reaches the first sensor 2 a.
[0042] Both sensors 16 are connected by wires (not shown) to an integral meter 6 . The meter 6 is optionally provided with means (not shown) for detecting gas flow in the chambers 2 . A first LED 26 on the meter 6 lights up when it detects the passage of gas 24 . The meter 6 measures the resistance of both sensors and produces a compared value which is the ratio of the resistances. The meter 6 displays a visible output accordingly, by illuminating (green) LED 20 corresponding to a negative test for H pylori, or (red) LED 22 corresponding to a positive test.
[0043] Based on data from in vitro studies, five healthy H. pylori -negative volunteers (determined by the 13 C breath test) were studied. In this work, the polypyrrole film was fabricated by dip coating a colloidal suspension of poly(pyrrole), after chemical oxidation of the pyrrole monomer, on an acrylic sheet using known methods (Ratcliffe NR. Poly(pyrrole)-based sensor for hydrazine and ammonia. Analytica Chimica Acta 1990; 239:257-262; Ratcliffe NR. The simple preparation of a conducting and transparent poly(pyrrole) film. Synthetic Metals 1990; 38:87-92).
[0044] The resultant film, approximately 50 nm thick, has a surface topography (revealed by transmission electron and atomic force microscopy) composed of spheres in intimate contact with each other. The volunteers were studied twice in random order on two separate days after an overnight fast; once after ingestion of an empty gelatin capsule and once after ingestion of a capsule containing 10 mg of NH 4 Cl. Three additional volunteers were studied only after ingestion of NH 4 Cl. Ten minutes after the capsule (a time sufficient for capsule degradation according to pharmacopoeia standards and our own in vitro observations), each subject swallowed a mixture of 15 ml of Milk of Magnesia® (BCH Ltd, Nottingham: containing 415 mg of Mg(OH) 2 per 5 ml) and 50 ml of water and, a further ten minutes later, drank 100 ml of sparkling water to ‘drive off’ any NH 3 . Mouth air samples (10 ml) were collected into a syringe at baseline (before the capsule); immediately prior to the Milk of Magnesia®/water mixture; and, finally, ten minutes after the 100 ml of sparkling water. These samples were individually expelled into a vial containing the NH 3 sensor linked to a multimeter (measuring resistance) as described above Pilot studies suggested, in contrast to in vitro data, that cold (4° C.) sparkling water was superior to still water, so the former was used in all in vivo studies.
[0045] Five patients (three males and two females) who tested positive for H. pylori with at least one clinically-validated test (e, g, 13 C breath test, serology) underwent the same procedure but without taking NH 4 Cl.
[0046] In vivo studies: H. pylori -negative subjects FIG. 5 summaries the changes in sensor chemoresistivity of mouth air in H. pylori -negative subjects who had ingested 10 mg NH 4 Cl or an empty gelatin capsule. FIG. 5 shows changes in electrical resistance for subjects exposed to mouth air from H pylori-negative subjects (“negative” controls), H pylori -negative subjects after ingestion of 10 mg ammonia chloride (“positive controls”) and H pylori -positive patients. On average, NH 3 levels detected in mouth air after ingestion of the NH 4 Cl-containing capsule, but prior to administration of the Milk of Magnesia/water mixture, were almost twice those seen after ingestion of the placebo. Furthermore, these data were obtained without the subjects necessarily belching.
[0047] In vivo studies: H. pylori -positive patients Five H. pylori -positive patients underwent the test protocol without taking the NH 4 Cl-containing capsule. The results are also shown in FIG. 5. Pre-protocol NH 3 levels in the patients' mouths were higher than the baseline levels measured in the H. pylori -negative subjects who ingested NH 4 Cl (“positive controls”) Furthermore, even higher levels were recorded in the four patients in whom the test protocol produced a belch.
[0048] None of the healthy volunteers or the H. pylori -positive patients experienced any adverse effects from the study.
[0049] The device and method of the present invention can detect sub-ppm concentrations of NH 3 in ‘endogenous’ mouth air, and can provide a point-of-care diagnostic test for Helicobacter pylon without the need for patients to ingest urea, and with the results being immediately available to the attending physician. Furthermore, the conditions necessary for the bacteria-associated NH 4 + to be converted to NH 3 and liberated through the oral cavity can be achieved through the use of an established antacid and cold, sparkling water with no adverse reactions amongst the small number of healthy subjects and H. pylori -positive patients so far tested.
[0050] Studies in the healthy volunteers clearly showed that NH 3 levels in mouth air after ingestion of 10 mg NH 4 Cl were generally higher than in the same subjects tested without ingestion of NH 4 Cl (FIG. 5). This difference was evident irrespective of whether or not the subjects belched. Removing the requirement to belch is seen as a significant advantage for a diagnostic test as, in a study with a larger number of normal subjects, only a proportion were induced to belch reliably under our current protocol.
[0051] Given the small number of subjects tested, there is some overlap in the data between those who ingested NH 4 Cl and those given the placebo. However, the data in FIG. 5 show markedly higher levels of mouth NH 3 in the overnight fasted H. pylori -positive patients than in either group of controls, Thus, the patients had higher baseline (without the need to belch) NH 3 levels than the healthy subjects even after the latter had ingested 10 mg NH 4 Cl. Furthermore, four of the five patients did belch and, in each case, this was associated with even higher mouth NH 3 levels. All these in vivo data were acquired without any subject or patient being required to ingest urea. The data also suggest that intra-gastric levels of NH 3 in patients with H. pylori infection are considerably higher than those attained by the ingestion of 10 mg of NH 4 Cl.
[0052] The invention provides a rapid, point-of-care diagnostic test for H. pylori based on the chemiresistive detection of NH 3 in mouth air. The proposed test does not require patients to ingest urea, and appears to be possible on ‘endogenous’ mouth air without the need for the patient to belch or even to ingest the antacid/water mixture. Additionally, the test method uses neither stable nor radioactive isotopes thus obviating the need to send samples to a central laboratory for analysis, and overcoming difficulties associated with radioisotopes.
[0053] While the invention has been described with reference to specific embodiments thereof, it is to be understood that the invention is not limited to the described embodiments. Many variants may be made within the spirit and scope of the invention. | A method for detecting Helicobacter pylori in a subject's gastroenteral tract involves measuring a change in resistance of an electronic or electrochemical sensor, notably a polypyrrole film, on exposure to gas from the subject's lungs and/or stomach. Depending on the magnitude of the change (if any) a positive or negative result is indicated visually by electronics means. Two sensors are used, one of which receives a sample of gas which has passed through an ammonia-absorbing means to provide a corrected baseline value for the ammonia. The invention also provides apparatus suitable for carrying out the method. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of International Patent Application No. PCT/CN2013/073012, filed on Mar. 21, 2013, which claims priority to Chinese Patent Application No. 201210076286.2, filed on Mar. 21, 2012, both of which are hereby incorporated by reference in their entireties.
TECHNICAL FIELD
The present invention relates to a field of communication technologies, and particularly, to a method and a device for determining a transmission power.
BACKGROUND
A wireless heterogeneous network (Heterogeneous Network, HetNet for short) is generally composed of various networks, such as a Macro cell, a Pico cell, a Femto cell, and the like. The different cells in the HetNet network may share the same radio resource. However, when different cells send downlink signals to respective pieces of user equipment (UE) using the same radio resource, signal interference may occur between the different cells, and thus user experience is degraded.
When a serving base station of an aggressor cell transmits a downlink signal on the same radio resource, the transmission power used on the same radio resource will affect the cell capacity of the aggressor cell and a victim cell. Specifically, when the aggressor cell transmits the downlink signal on the same radio resource at a lower transmission power, the capacity of the victim cell could increase by sacrificing the capacity of the aggressor cell itself, on the contrary, when the aggressor cell transmits the downlink signal on the same radio resource at a higher transmission power, the aggressor cell would increase its own capacity by sacrificing the capacity of the victim cell. Up to now, there is no effective solution to set the transmission power used by the serving base station of the aggressor cell on the same radio resource so that a reasonable compromise between the cell capacities of the aggressor cell and the victim cell can be guaranteed.
SUMMARY
An aspect of the present invention provides a method for determining a transmission power, including: receiving, by a power determining device, capacity information of a first cell sent by a serving base station of the first cell, wherein the capacity information of the first cell corresponds to a transmission power preset by a serving base station of a second cell on a specific resource of the second cell, and the specific resource is a radio resource shared by the first cell and the second cell; and determining, by the power determining device, a transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell.
Another aspect of the present invention provides a power determining device, including: a receiver and a first processor, wherein the receiver is configured to receive capacity information of a first cell sent by a serving base station of the first cell, the capacity information of the first cell corresponds to a transmission power preset by a serving base station of a second cell on a specific resource of the second cell, the specific resource is a radio resource shared by the first cell and the second cell, and the first processor is configured to determine a transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell.
Still another aspect of the present invention provides a method for determining a transmission power, including: sending, by a serving base station of a first cell, capacity information of the first cell to a serving base station of a second cell, wherein the capacity information of the first cell corresponds to a transmission power preset by the serving base station of the second cell on a specific resource of the second cell, the specific resource is a radio resource shared by the first cell and the second cell; and the first capacity information is used by the serving base station of the second cell to determine a transmission power used on the specific resource of the second cell.
Another aspect of an embodiment of the present invention provides a base station, including: a transmitter, configured to send capacity information of a first cell to a serving base station of a second cell, wherein the capacity information of the first cell corresponds to a transmission power preset by the serving base station of the second cell on a specific resource of the second cell, the specific resource is a radio resource shared by the first cell and the second cell, and the first capacity information is used by the serving base station of the second cell to determine a transmission power used on the specific resource of the second cell.
With the above-mentioned technical solution provided in the present invention, the power determining device receives the capacity information of the first cell sent by the serving base station of the first cell, and determines the transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell, and thus the capacity of the first cell (i.e. victim cell) can be guaranteed.
BRIEF DESCRIPTION OF DRAWINGS
To illustrate technical solutions in embodiments of the present invention more clearly, a brief introduction on the accompanying drawings which are needed in the description of the embodiments of the present invention will be given below. The accompanying drawings described below are only some of the embodiments of the present invention.
FIG. 1 is a schematic flow chart illustrating a method for determining a transmission power as provided by a specific embodiment of the present invention;
FIG. 2 is a schematic flow chart illustrating a method for determining a transmission power as provided by a specific embodiment of the present invention;
FIG. 3 is a schematic flow chart illustrating a method for determining a transmission power as provided by a specific embodiment of the present invention;
FIG. 4 is an apparatus schematic block diagram illustrating a power determining device as provided by a specific embodiment of the present invention;
FIG. 5 is an apparatus schematic block diagram illustrating a power determining device as provided by a specific embodiment of the present invention;
FIG. 6 is an apparatus schematic block diagram illustrating a power determining device as provided by a specific embodiment of the present invention;
FIG. 7 is an apparatus schematic block diagram illustrating a base station as provided by a specific embodiment of the present invention;
FIG. 8 is an apparatus schematic block diagram illustrating a base station as provided by a specific embodiment of the present invention; and
FIG. 9 is a schematic diagram illustrating a system for determining a transmission power as provided by a specific embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
To make the objectives, technical solutions, and advantages of the present invention more clear, embodiments of the present invention are hereinafter described in detail, with reference to the accompanying drawings.
Referring to FIG. 1 , an embodiment provides a method for determining a transmission power, and includes the following content.
At 101 , a power determining device receives capacity information of a first cell sent by a serving base station of the first cell, wherein the capacity information of the first cell corresponds to a transmission power preset by a serving base station of a second cell on a specific resource of the second cell, and the specific resource is a radio resource shared by the first cell and the second cell.
At 103 , the power determining device determines a transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell.
With the above-mentioned technical solution provided by the present embodiment, a power determining device receives capacity information of a first cell sent by a serving base station of the first cell, and determines a transmission power used by a serving base station of a second cell on the specific resource of the second cell according to the capacity information of the first cell, and thus the capacity of the first cell can be guaranteed.
In the embodiment of the present invention, a victim cell is referred to as the first cell and an aggressor cell is referred to as the second cell, and the radio resource shared by the first cell and the second cell is referred to as the specific resource. In the following embodiments, the serving base station of the first cell may be referred to as the first base station for short and the serving base station of the second cell may be referred to as the second base station for short.
Specifically, in the above 103 , that the power determining device determines the transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell, includes that the power determining device calculates an average capacity of the first cell according to the capacity information of the first cell, and determines the transmission power used by the serving base station of the second cell on the specific resource of the second cell. More specifically, that the power determining device determines the transmission power used by the serving base station of the second cell on the specific resource of the second cell, includes that the power determining device determines a maximum transmission power at which the average capacity of the first cell satisfies a predetermined capacity threshold, and takes the maximum transmission power as the transmission power used by the serving base station of the second cell on the specific resource of the second cell.
In a process of implementation, assume that the power determining device receives capacity information of first cells sent by N first base stations, and assume that the transmission powers preset by the second base station on the specific resource of the second cell are P 1 , P 2 , P 3 , and P 4 . For example: the capacities of the first cell calculated by the first base station No. 1 are C 1 ( 1 ), C 2 ( 1 ), C 3 ( 1 ) and C 4 ( 1 ), which have a one-to-one correspondence with transmission powers P 1 , P 2 , P 3 , and P 4 preset by the second base station on the specific resource of the second base station; the capacities of the first cell calculated by the first base station No. 2 are C 1 ( 2 ), C 2 ( 2 ), C 3 ( 2 ) and C 4 ( 2 ), which have a one-to-one correspondence with the transmission powers P 1 , P 2 , P 3 , and P 4 preset by the second base station on the specific resource of the second cell; the capacities of the first cell calculated by the first base station No. N are C 1 (N), C 2 (N), C 3 (N) and C 4 (N), which have a one-to-one correspondence with the transmission powers P 1 , P 2 , P 3 , and P 4 preset by the second base station on the specific resource of the second cell.
The power determining device calculates the average capacities of the N first cells which correspond to the transmission powers P 1 , P 2 , P 3 and P 4 preset by the second base station on the specific resource of the second cell respectively, and for P 1 , the average capacity of the N first cells is:
C ( P 1 ) = L k N ∑ k = 1 N C 1 ( k ) ,
wherein L k is a load factor of the first cell No. k. In a process of implementation, the first base station and the second base station exchange their load information when establishing an X2 connection. The second base station receives the load information sent by the first base station, and parses the load information to obtain the load factor of the first cell. The average capacities of the N first cells corresponding to the remaining P 2 , P 3 and P 4 are calculated in a similar manner.
The power determining device determines the maximum transmission power at which the average capacity of the N first cells satisfies a predetermined capacity threshold (Cthreshold), and takes the maximum transmission power as the transmission power used by the serving base station of the second cell on the specific resource of the second cell. For example, assuming P 1 <P 2 <P 3 <P 4 , and that the average capacities of the N first cells corresponding to P 1 and P 2 satisfy the predetermined capacity threshold Cthreshold, the power determining device preferentially selects P 2 as the transmission power used by the serving base station of the second cell on the specific resource of the second cell. That is, while the threshold of the average capacity of the N first cells is satisfied, the larger transmission power may enable a larger capacity of the second cell.
In the above-mentioned embodiment, the power determining device receives the capacity information of the first cell sent by the serving base station of the first cell, the transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell, so that the average capacity of the first cell is larger than a certain capacity threshold, and thus the capacity of the first cell is guaranteed.
In an optional embodiment, the above-mentioned embodiment may further at 102 , the power determining device obtains capacity information of the second cell, wherein the capacity information of the second cell corresponds to the transmission power preset by serving base station of the second cell on the specific resource of the second cell. The 101 and 102 may be executed simultaneously or there is no limitation on the order by which those two steps are executed.
In this case, the above 103 could be: 103 ′, the power determining device the transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell and the capacity information of the second cell. With the above-mentioned optional embodiment, the maximization of the total capacity of the first cell and the second cell can be guaranteed.
In a process of implementation, the method of the above-mentioned optional embodiment, specifically includes: the first base station sends the capacity information of the first cell to the second base station or a control node, wherein the capacity information of the first cell corresponds to the transmission power preset by the second base station on the specific resource of the second cell; after receiving the capacity information of the first cell, the second base station or the control node obtains the capacity information of the second cell, wherein the capacity information of the second cell also corresponds to the transmission power preset by the second base station on the specific resource of the second cell; after that, the second base station or the control node determines the transmission power used by the second base station on the specific resource of the second cell according to the capacity information of the first cell and the capacity information of the second cell, to guarantee that the total capacity of the first cell and the second cell may be maximized.
In an embodiment of the present invention, the control node includes but is not limited to a mobility management entity (MME), a network management node OAM (Operation, Administration, Maintenance), or an operation support system (OSS) in a core network. In an embodiment of the present invention, the control node may also be a base station different from the first base station and the second base station.
In an embodiment of the present invention, the specific resource may include one or more of time domain resource, frequency domain resource and space domain resource, wherein the time domain resource, the frequency domain resource or the space domain resource may include but not limits to a single carrier, a set of carriers, a single almost blank subframe (ABS), a set of ABSs, a single physical resource block, a set of physical resource blocks, a single beam or a set of beams.
In an embodiment of the present invention, the transmission power on the specific resource generally has 8 optional step values, in particular, is determined by the pre-configured configuration parameters Pa and Pb together. Pb is set for a cell (is cell-specific), Pa is set for a user equipment in the cell (is UE-specific), and specifically, the configuration of the configuration parameters of the transmission power on the specific resource may be as follows:
PDSCH-ConfigCommon: : =SEQUENCE{
referenceSignalpower
INTEGER(−60..50),
p-b
INTEGER (0..3) //configuration of
configuration
parameter Pb
}
PDSCH-ConfigDedicated::=SEQUENCE{
p-a
ENUMERATED{
db−6,db−4dot77,db−3,db−1dot77,
db0,db1,db2,db3}
//configuration of
configuration
parameter Pa, 8 step values in total
}
For the application scenario of the enhanced Inter-Cell Interference Coordination (eICIC) mechanism, the specific resource is a single ABS subframe or a set of ABS subframes. Specifically, as the specific resource, the single ABS or the set of ABS subframes is preset by the second base station, for example, the second base station designates an ABS subframe or a set of subframes as ABS subframe(s), and the setting condition of the ABS subframe(s) may be identified by an ABS subframe pattern.
In an embodiment of the present invention, the ABS subframe pattern (ABS Pattern) f(m) also identifies the proportion of the number of the ABS subframes set by the second base station to the total number of the subframes. For example, the ABS subframe pattern includes pattern ⅛, 2/8, 3/20 or the like, wherein the pattern ⅛ indicates that one of the eight subframes is set as the ABS subframe by the base station of the aggressor cell, the pattern 2/8 indicates that two of the eight subframes are set as ABS subframes by the base station of the aggressor cell, and similarly, the pattern 3/20 indicates that three of the twenty subframes are set as the ABS subframes by the base station of the aggressor cell. Specifically, the setting condition of the ABS subframes is shown as follows:
FDD patterns;
(1/8,1,ABS)
[10000000,......] // the ABS subframe is
indicated by 1, and the non-ABS subframe is indicated by 0
(2/8,2,ABS)
[11000000,......] // the ABS subframe is indicated
by 1, and the non-ABS subframe is indicated by 0
(3/20,1,MBSF)
[1000010000 1000000000] // the ABS
subframe is indicated by 1, and the non-ABS subframe is indicated by 0.
Then, in order to guarantee that the total capacity of the first cell and the second cell may be maximized, it is necessary to determine the transmission power used by the second base station on a single ABS or a set of ABSs. Specifically referring to FIG. 2 , a method for determining a transmission power includes the following content.
At 201 , a first base station determines a second cell. Specifically, the first base station determines the second cell according to measurement information of each of the neighboring cells reported by a user equipment served by the first cell, wherein the measurement information may include but not limits to a reference signal receiving power (Reference Signal Receiving Power, RSRP) or a channel quality indicator (Channel Quality Indicator, CQI).
In implementation of an embodiment of the present invention, the first base station configures the user equipment served by the first cell to measure the RSRP of each of the neighboring cells; the first base station receives the RSRPs of each of the neighboring cells reported by the user equipment served by the first cell; then, the first base station averages the RSRPs of a same neighboring cell reported by the user equipment served by the first cell, obtains the average RSRP of each of the neighboring cells, and takes the neighboring cell with maximum average RSRP as the second cell.
In addition, in implementation of an embodiment of the present invention, the first base station may configure the user equipment served by the first cell to measure the CQI of the neighboring cell, and when the first base station calculates the average RSRP of each of the neighboring cells, the first base station may average the RSRPs of a same neighboring cell reported by the user equipment, served by the first cell, whose channel quality indicator (Channel Quality Indicator, CQI) is less than a first predetermined value, to obtain the average RSRP of each of the neighboring cells, so as to reduce the computation and improve the efficiency of determining the second cell.
Alternatively, in implementation of an embodiment of the present invention, the first base station configures the user equipment served by the first cell to measure the RSRP of each of the neighboring cells; the first base station receives the neighboring cells whose RSRPs are larger than a second predetermined value reported by the user equipment served by the first cell; then the first base station does statistics on the occurrence probability of each of the neighboring cells reported by the user equipment served by the first cell, and takes the neighboring cell with the largest occurrence probability as the second cell.
In addition, in implementation of an embodiment of the present invention, the first base station may configure the user equipment served by the first cell to measure the CQI of each of the neighboring cells, and when the first base station does statistics on the occurrence times of each of the neighboring cells, the first base station may only do statistics on that of the neighboring cells reported by the user equipment, served by the first cell, whose CQI is less than the first predetermined value, so as to reduce the computation and improve the efficiency of determining the second cell.
Of course, in implementation of an embodiment of the present invention, the first base station may configure the user equipment served by the first cell to measure and report the CQI of the neighboring cell, and determine the second cell according to the CQI reported by the user equipment. The determining manner is the same as the method for determining the second cell according to the RSRPs reported by the user equipment served by the first cell, and thus will not be described redundantly herein.
At 202 , the first base station calculates capacity information of the first cell corresponding to a transmission power preset by the second base station on the specific resource of the second cell, wherein the capacity information may include but not limit to capacity or frequency spectrum efficiency.
In an embodiment of the present invention, the transmission power preset by the second base station on the specific resource of the second cell could be: the transmission power of the second base station on the specific resource of the second cell pre-negotiated by the first base station and the second base station through an X2 interface when the X2 interface is established between the first base station and the second base station.
In addition, in an embodiment of the present invention, the transmission power preset by the second base station on the specific resource of the second cell could be the transmission power of the second base station on the specific resource of the second cell set by the first base station.
Specifically, that the first base station calculates the capacity information of the first cell which corresponds to the transmission power preset by the second base station on the specific resource of the second cell may include: calculating the capacity information of the first cell which corresponds to the transmission power preset by the second base station on the specific resource of the second cell according to the measurement information of the current cell and the neighboring cells reported by the user equipment served by the first cell, wherein the measurement information may include but not limit to an RSRP or a CQI.
In an embodiment of the present invention, when there are a plurality of transmission powers preset by the second base station on the specific resource of the second cell, there are also a plurality of pieces of capacity information of the first cell which have a one-to-one correspondence with the transmission powers preset by the second base station on the specific resource of the second cell.
In implementation of an embodiment of the present invention, if the capacity information of the first cell is a capacity of the first cell, the first base station may calculate pieces of capacity information of the first cell which have a one-to-one correspondence with a plurality of transmission powers preset by the second base station on the specific resource of the second cell according to the measurement information of the current cell and the neighboring cells reported by the user equipment served by the first cell by using calculation manners as follows:
Manner 1: if the first base station schedules each of the user equipments served by the first cell on a specific resource of the first cell respectively in a round robin (Round Robin, RR) scheduling manner, and the specific resource is a single ABS or a set of ABSs, then each of a plurality of transmission powers preset by the second base station on the specific resource of the second cell is taken as a current power in turn, and the capacity of the first cell corresponding to the current power is calculated, specifically including: calculating the capacity obtained by each of the user equipments scheduled on the specific resource of the first cell according to the measurement information of the current cell and the neighboring cells reported by each of the user equipments served by the first cell, and then calculating the capacity of the first cell corresponding to the current power according to the capacity obtained by each of the user equipments scheduled on the specific resource of the first cell.
In an optional embodiment, taking the measurement information being RSRP as an example, calculating the capacity obtained by each of the user equipments scheduled on the specific resource includes:
When a user equipment UEn served by the first cell is scheduled on the specific resource of the first cell, that is, when the first base station sends downlink signal to the UEn by using the specific resource in the first cell. As an optional embodiment, the following Equation 1 may be used to calculate the capacity obtained by the UEn scheduled on the specific resource of the first cell.
C
n
ABS
(
m
,
x
)
=
log
2
{
1
+
RSRP
i
∑
k
=
0
,
k
≠
m
K
x
k
RSRP
k
+
x
*
RSRP
m
}
(
Equation
1
)
Before explaining every item in Equation 1, it is to be noted that the second cell determined in step 201 is a strong aggressor cell of the first cell, and in implementation, in addition to strong interference from the second cell, the first cell may be weakly interfered with by other cells. Herein, the cells other than the second cell which interfere with the first cell are referred to as third cells. In an embodiment of the present invention, in order to further guarantee the capacity of the first cell, besides considering the strong interference from the second cell, the interference from the third cell is also considered.
Furthermore, before the first base station calculates the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell, the first base station obtains information about the ABS subframe set by the second base station, and obtains information about the ABS subframe set by a serving base station of each cell in the third cells respectively, wherein the information about the ABS subframe includes but is not limited to an ABS subframe pattern.
Specifically, the first base station receives the information about the ABS subframe (ABS information) sent by the second base station through the X2 interface established with the second base station, and receives the information about the ABS subframe sent by the serving base station of each cell in the third cells through the X2 interface established therebetween.
Hereinafter, every item in Equation 1 is described in detail, and in particular C n ABS (m,x) is the capacity obtained by the UEn scheduled on the specific resource of the first cell; RSRP i is the RSRP of the current cell (i.e. the first cell) reported by the UEn; RSRP k is the RSRP of the neighboring cell, in particular, the kth cell in the third cells, reported by the UEn; RSRP m , is the RSRP of the neighboring cell, in particular, the second cell, reported by the UEn; X k is the ratio of the transmission power used by the serving base station of the kth cell in the third cells on the specific resource of the kth cell with respect to the transmission power of the reference signal (Reference Signal, RS) sent by itself.
In an embodiment of the present invention, the first base station determines whether or not the specific resource set by the second base station is the ABS subframe set by the serving base station of the kth cell, according to the previously obtained ABS subframe information set by the second base station and the ABS subframe information set by the serving base station of the kth cell. If the specific resource set by the second base station is not the ABS subframe set by the serving base station of the kth cell, then X k =1. If the specific resource set by the second base station is the ABS subframe set by the serving base station of the kth cell, then the first base station may receive the X k sent by the serving base station of the kth cell through the X2 interface which has been established with the serving base station of the kth cell. The X in Equation 1 is the ratio of the current power with respect to the transmission power at which the second base station sends the RS, wherein the current power is one of the configurable eight step values of the transmission power described above.
After calculating the capacity obtained by each of the user equipments served by the first cell scheduled on the specific resource of the first cell according to Equation 1, the first base station adds up the capacity obtained by each of the user equipments on the specific resource of the first cell to get an average value, and obtains the capacity of the first cell corresponding to the current power. In an optional embodiment, in particular, the following Equation 2 may be used to calculate the capacity of the first cell corresponding to the current power:
C
i
Pico
(
m
,
x
)
=
1
N
∑
n
=
0
N
C
n
ABS
(
m
,
x
)
(
Equation
2
)
In Equation 2, C i pico (m,x) is the capacity of the first cell corresponding to the current power; N is the total number of the user equipments served by the first cell, and since the user equipments served by the base station have been registered in the base station, the first base station may be aware of the total number of the user equipments served by the first cell; C n ABS (m,x) is the capacity of the first cell obtained by the user equipments served by the first cell scheduled on the specific resource of the first cell.
In implementation of this embodiment, when the measurement information is a CQI, the method for calculating the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell includes: obtaining the frequency spectrum efficiency corresponding to the reported CQI directly according to a CQI reported by the user equipment served by the first cell on the specific resource of the first cell; then processing, e.g. averaging, weightedly averaging, or the like, the frequency spectrum efficiency corresponding to the CQI reported by all the user equipments, to obtain the processed frequency spectrum efficiency of the first cell, and takes it as the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell.
Manner 2: if the first base station schedules the user equipment served by the first cell on the specific resource or non-specific resource of the first cell in a round robin (Round Robin, RR) scheduling manner, the specific resource is a single ABS or a set of ABSs, and the non-specific resource is a single non-ABSs or a set of non-ABSs, then each of a plurality of values of transmission power preset by the second base station on the specific resource of the second cell is taken as a current power in turn, and the capacity of the first cell corresponding to the current power is calculated, specifically, including: calculating the capacity obtained on the specific resource of the first cell by each of the user equipments scheduled on the specific resource of the first cell according to measurement information of the current cell and the neighboring cells reported by each of the user equipments scheduled on the specific resource of the first cell; and calculating the capacity obtained on the non-specific resource of the first cell by each of the user equipments scheduled on the non-specific resource of the first cell according to measurement information of the current cell and the neighboring cells reported by each of the user equipments scheduled on the non-specific resource of the first cell; then calculating the capacity of the first cell corresponding to the current power, according to the capacity obtained on the specific resource of the first cell by each of the user equipments scheduled on the specific resource of the first cell and the capacity obtained on the non-specific resource of the first cell by each of the user equipments scheduled on the non-specific resource of the first cell.
In an optional embodiment, taking the measurement information being RSRP as an example, the calculating manner, in which the obtained capacity on the specific resource of the first cell by each of the user equipments scheduled on the specific resource of the first cell is calculated, may refer to Equation 1, and thus will not be described redundantly herein.
In another optional embodiment, taking the measurement information being RSRP as an example, the following Equation 3 may be used to calculate the capacity obtained on the non-specific resource of the first cell by each of the user equipments scheduled on the non-specific resource of the first cell:
C
n
non
-
ABS
(
m
,
x
)
=
log
2
{
1
+
RSRP
i
∑
k
=
0
K
RSRP
k
}
(
Equation
3
)
In Equation 3, C n non-ABS (m,x) is the capacity obtained on the non-specific resource by the UEn scheduled on the non-specific resource of the first cell; RSRP i is the RSRP of the current cell, i.e. the first cell, reported by the user equipment scheduled on the non-specific resource of the first cell; RSRP k is the RSRP of the neighboring cell, in particular, the kth cell in the third cells, reported by the user equipment scheduled on the non-specific resource of the first cell.
In an optional embodiment, the first base station may process, by using the following Equation 4, the cell capacity obtained on the specific resource of the first cell by each of the user equipments scheduled on the specific resource of the first cell which is calculated by Equation 1 and Equation 2 and the cell capacity obtained on the non-specific resource of the first cell by each of the user equipments scheduled on the non-specific resource of the first cell, to obtain the capacity of the first cell corresponding to the current transmission power:
C
i
Pico
(
m
,
x
)
=
f
(
m
)
N
∑
n
=
0
N
C
n
ABS
(
m
,
x
)
+
1
-
f
(
m
)
N
∑
n
=
0
N
C
n
non
-
ABS
(
m
,
x
)
(
Equation
4
)
In Equation 4, C i pico (m,x) is the capacity of the first cell corresponding to the current power; C n ABS (m,x) is the capacity obtained on the specific resource of the first cell by the user equipment scheduled on the specific resource of the first cell; C n non-ABS (m,x) is the capacity obtained on the non-specific resource of the first cell by the user equipment scheduled on the non-specific resource of the first cell; N is the total number of the user equipments served by the first base station, wherein since the user equipments served by the base station have been registered in the base station, the first base station may be aware of the total number of the user equipments served by the first cell; and f(m) in Equation 4 is an ABS pattern set by the second base station.
In implementation of this embodiment, when the measurement information is a CQI, the method for calculating the capacity information of the first cell corresponding to the transmission power preset on the specific resource of the second cell by the second base station includes: obtaining the frequency spectrum efficiency corresponding to the reported CQI directly according to the CQI reported by the user equipment served by the first cell on the specific resource of the first cell, and then processing, e.g. averaging, weighted averaging, or the like, the frequency spectrum efficiency corresponding to the CQIs reported by all the user equipments, to obtain the processed frequency spectrum efficiency of the first cell, and taking it as the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell.
Manner 3: If the first base station schedules a user equipment located in a cell range extension (Cell Range Extension, CRE) area on the specific resource of the first cell in an RR scheduling manner, schedules user equipments in other areas on the non-specific resource of the first cell in the RR manner, the specific resource is a single ABS or a set of ABSs, and the non-specific resource is a single non-ABS or a set of non-ABSs, then each of a plurality of transmission powers preset by the second base station on the specific resource of the second cell is taken as a current power in turn, and calculates the capacity of the first cell corresponding to the current power, specifically, including: calculating the capacity obtained on the specific resource of the first cell by each of the user equipments scheduled on the specific resource of the first cell according to measurement information of the current cell and the neighboring cell reported by each of the user equipments scheduled on the specific resource of the first cell; calculating the capacity obtained on the non-specific resource of the first cell by each of the user equipments scheduled on the non-specific resource of the first cell according to measurement information of the current cell and the neighboring cell reported by each of the user equipments scheduled on the non-specific resource of the first cell; then calculating the capacity of the first cell corresponding to the current power, according to the capacity obtained on the specific resource of the first cell by each of the user equipments scheduled on the specific resource of the first cell and the capacity obtained on the non-specific resource of the first cell by each of the user equipments scheduled on the non-specific resource of the first cell.
As an optional embodiment, taking the measurement information being RSRP as an example, the calculating manner, in which the obtained capacity on the specific resource of the first cell by each of the user equipments scheduled on the specific resource of the first cell is calculated, may refer to the Equation 1, and thus will not be described redundantly herein.
As another optional embodiment, taking the measurement information being RSRP as an example, the calculating manner, in which the obtained capacity on the non-specific resource of the first cell by each of the user equipments scheduled on the non-specific resource of the first cell is calculated, may refer to the Equation 3, and thus will not be described redundantly herein.
In an optional embodiment, the first base station may process, by using the following Equation 5, the capacity obtained on the specific resource of the first cell by each of the user equipments scheduled on the specific resource of the first cell and the capacity obtained on the non-specific resource of the first cell by each of the user equipments scheduled on the non-specific resource of the first cell, to obtain the capacity of the first cell corresponding to the current power:
C
i
Pico
(
m
,
x
)
=
f
(
m
)
L
∑
n
∈
S
L
C
n
ABS
(
m
,
x
)
+
1
-
f
(
m
)
N
-
L
∑
n
∈
SIS
L
C
n
non
-
ABS
(
m
,
x
)
(
Equation
5
)
In Equation 5, C i pico (m,x) is the capacity of the first cell corresponding to the current power; C n ABS (m,x) is the capacity obtained on the specific resource of the first cell by the user equipment scheduled on the specific resource of the first cell; C n non-ABS (m,x) is the capacity obtained on the non-specific resource of the first cell by the user equipment scheduled on the non-specific resource of the first cell; N is the total number of the user equipments served by the first base station, wherein since the user equipments served by the base station have been registered in the base station, the first base station may be aware of the total number of the user equipments served by the first cell; f(m) is an ABS pattern set by the second base station; and L is the number of the user equipments located in the CRE extension area of the first cell.
In implementation of this embodiment, when the measurement information is a CQI, the method for calculating the capacity information of the first cell corresponding to the transmission power preset on the specific resource of the second cell by the second base station includes: obtaining the frequency spectrum efficiency corresponding to the reported CQI directly according to the CQI reported by the user equipment served by the first cell on the specific resource of the first cell, then processing, e.g. averaging, weightedly averaging, or the like, the frequency spectrum efficiency corresponding to the CQI reported by all the user equipments, to obtain the processed frequency spectrum efficiency of the first cell, and taking it as the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell.
At 203 , the first base station sends the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell to a power determining device.
In an embodiment of the present invention, specifically, the power determining device may be the second base station or a control node. For the scenario in which the first base station and the power determining device have pre-negotiated the transmission power preset by the second base station on the specific resource of the second cell, the first base station only sends the calculated capacity information of the first cell to the power determining device.
For the scenario in which the first base station and the power determining device have not pre-negotiate the transmission power preset by the second base station on the specific resource of the second cell, when the first base station sends the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell to the power determining device, the first base station further sends information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the first cell to the power determining device.
The information about the transmission power preset by the second base station on the specific resource of the second cell may specifically include but not limit to the transmission power preset by the second base station on the specific resource of the second cell or the level information of the transmission power preset by the second base station on the specific resource of the second cell.
In an embodiment of the present invention, if the power determining device is the control node, when sending the capacity information of the first cell to the control node, the first base station also sends the identity of the second base station to the control node, so that the control node may determine the transmission power used by the second base station, which is identified by the received identification, on the specific resource of the second cell.
In specific implementation of an embodiment of the present invention, if the power determining device is the second base station, then the first base station sends the capacity information of the first cell and/or the information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the first cell to the second base station through an X2 interface established with the second base station.
If the power determining device is the control node, for example, if the control node is an MME, then the first base station sends the capacity information of the first cell and/or the information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the first cell to the control node through an S1 interface established with the MME; and if the control node is an OAM, the first base station sends the capacity information of the first cell and/or the information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the first cell to the control node through a southbound interface Itf-S established with the OAM.
At 204 , after receiving the capacity information of the first cell sent by the first base station, the power determining device obtains capacity information of the second cell, wherein the capacity information of the second cell corresponds to the transmission power preset by the second base station on the specific resource of the second cell.
Specifically, obtaining the capacity information of the second cell may include the following. If the power determining device is the second base station, for the scenario in which the first base station and the power determining device have pre-negotiated the transmission power preset by the second base station on the specific resource of the second cell, the second base station calculates the capacity information of the second cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell, according to the transmission power preset on the specific resource of the second cell and the measurement information of the current cell and the neighboring cell reported by the user equipment served by the second cell. In this scenario, the transmission power preset by the second base station on the specific resource of the second cell is the transmission power of the second base station on the specific resource of the second cell pre-negotiated by the first base station and the second base station.
If the power determining device is the second base station, for the scenario in which the first base station and the power determining device have not pre-negotiated the transmission power preset by the second base station on the specific resource of the second cell, the second base station receives the information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the first cell sent by the first base station; and then the second base station calculates the capacity information of the second cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell, according to the transmission power preset on the specific resource of the second cell and the measurement information of the current cell and the neighboring cells reported by the user equipment served by the second cell. In this scenario, the transmission power preset by the second base station on the specific resource of the second cell is the received power which corresponds to the information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the first cell.
If the power determining device is the second base station, for the scenario in which the first base station and the power determining device have not pre-negotiated the transmission power preset by the second base station on the specific resource of the second cell, the second base station receives the information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the first cell sent by the first base station; and then the second base station calculates the capacity information of the second cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell, according to the transmission power preset on the specific resource of the second cell and the measurement information of the current cell and the neighboring cells reported by the user equipment served by the second cell. In this scenario, the transmission power preset by the second base station on the specific resource of the second cell is the received power which corresponds to the information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the first cell.
In an embodiment of the present invention, the process that the second base station calculates the capacity information of the second cell may refer to the process in step 202 in which the first base station calculates the capacity information of the first cell, and thus will not be described redundantly herein.
If the power determining device is the control node, the control node receives the capacity information of the second cell sent by the second base station. If the power determining device is the control node, for the scenario in which the first base station and the power determining device have not pre-negotiated the transmission power preset by the second base station on the specific resource of the second cell, when the control node receives the capacity information of the second cell sent by the second base station, the control node further receives the information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the second cell, which is sent by the second base station.
At 205 , the power determining device determines the transmission power used by the second base station on the specific resource of the second cell, according to the capacity information of the first cell and the capacity information of the second cell.
In implementation of an embodiment of the present invention, if there are a plurality of transmission powers preset by the second base station on the specific resource of the second cell, then there are a plurality of pieces of capacity information of the first cell which have a one-to-one correspondence with the transmission powers preset by the second base station on the specific resource of the second cell, and there are a plurality of pieces of capacity information of the second cell which have a one-to-one correspondence with the transmission powers preset by the second base station on the specific resource of the second cell.
Then, determining the transmission power used by the second base station on the specific resource of the second cell according to the capacity information of the first cell and the capacity information of the second cell includes: calculating the total capacity information of the first cell and the second cell according to the capacity information of the first cell and the capacity information of the second cell, wherein there are a plurality of pieces of total capacity information which correspond to the transmission powers preset by the second base station on the specific resource of the second cell; selecting the maximum total capacity information from the plurality pieces of total capacity information calculated, and taking the power corresponding to the maximum total capacity information as the transmission power used by the second base station on the specific resource of the second cell.
For the scenario in which the first base station and the power determining device (e.g. the second base station) have pre-negotiated the transmission power preset by the second base station on the specific resource of the second cell, an example is taken to explain steps 202 to 204 . In the example, the first base station calculates the capacities of the first cell C 1 , C 2 , C 3 and C 4 which have a one-to-one correspondence with the transmission powers P 1 , P 2 , P 3 , and P 4 preset by the second base station on the specific resource of the second cell; the second base station calculates the capacities of the second cell C 1 ′, C 2 ′, C 3 ′ and C 4 ′ which have a one-to-one correspondence with the transmission powers P 1 , P 2 , P 3 , and P 4 preset by the second base station on the specific resource of the second cell; the second base station calculates the total capacities of the first cell and second cell C 1 +C 1 ′, C 2 +C 2 ′, C 3 +C 3 ′ and C 4 +C 4 ′ which have a one-to-one correspondence with the transmission powers P 1 , P 2 , P 3 , and P 4 preset by the second base station on the specific resource of the second cell; and the second base station selects the maximum total capacity from C 1 +C 1 ′, C 2 +C 2 ′, C 3 +C 3 ′ and C 4 +C 4 ′, e.g. C 4 +C 4 ′, and then the power P 4 corresponding to C 4 +C 4 ′ would be the transmission power used by the second base station on the specific resource.
Furthermore, in an embodiment of the present invention, the second cell, as an interference source, may strongly interfere with a plurality of different first cells; then it can be appreciated based on the above description that, each of the first base stations will send a piece of capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell to the power determining device; in this way, the power determining device shall receive a plurality of pieces of capacity information of the first cells. After that, the power determining device obtains the capacity information of the second cell, the capacity information of the second cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell, and determines the transmission power of the second base station on the specific resource of the second cell according to the plurality of pieces of received capacity information of the first cells and the obtained capacity information of the second cell.
Specifically, the power determining device determines the transmission power of the second base station on the specific resource of the second cell according to the plurality of pieces of received capacity information of the first cells and the obtained capacity information of the second cell: the power determining device determines the total capacity information of the plurality of first cells according to the plurality of received capacity information of the first cells; the power determining device calculates the total capacity information of the plurality of first cells and second cells according to the total capacity information of the plurality of first cells and the capacity information of the second cell; when there are a plurality of transmission powers preset by the second base station on the specific resource of the second cell, there are a plurality of pieces of capacity information of the first cells which have a one-to-one correspondence with the transmission powers preset by the second base station on the specific resource of the second cell, there are a plurality of pieces of capacity information of the second cell which have a one-to-one correspondence with transmission powers preset by the second base station on the specific resource of the second cell, there are a plurality of pieces of total capacity information of the plurality of first cells which have a one-to-one correspondence with the transmission powers preset by the second base station on the specific resource of the second cell, and there are a plurality of pieces of total capacity information of the plurality of first cells and the second cell which have a one-to-one correspondence with the transmission powers preset by the second base station on the specific resource of the second cell; in this case, the maximum value of total capacity information is selected from the plurality of pieces of total capacity information, and the power corresponding to the maximum total capacity information is taken as the transmission power used by the second base station on the specific resource of the second cell.
In an optional embodiment, the total capacity information of the plurality of first cells and second cell may be calculated by using the following Equation 6:
C
(
m
,
x
)
=
L
i
Pico
∑
i
=
0
C
i
Pico
(
m
,
x
)
+
L
m
Macro
*
C
m
Macro
(
m
,
x
)
(
Equation
6
)
In Equation 6, C(m,x) is total capacity information of i first cells and the second cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell; L i pico is a load factor of the first cell;
∑ i = 0 C i pico ( m , x )
is capacity information of the ith first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell; C m macro (m,x) is the capacity information of the second cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell; and L m Macro is a load factor of the second cell.
In an embodiment of the present invention, when the first base station and the second base station establish an X2 connection, the first base station and the second base station transmit their respective load information to each other. The second base station receives the load information sent by the first base station and parses the load information to obtain the load factor of the first cell, wherein the load factor of the second cell may be obtained from its own load information.
In specific implementation of the embodiment of the present invention, for the scenario of carrier aggregation (CA), the specific resource is a single carrier or a set of carriers. In the scenario of CA, if the capacity information of the first cell is the capacity of the first cell, the method for determining the transmission power is similar with the method for determining the transmission power in the scenario of eICIC. The difference is, in the scenario of CA, the way by which the first base station calculates the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell, according to the measurement information of the current cell and the neighboring cell reported by the user equipment served by the first cell, is different from the way employed in the scenario of eICIC. A detailed description is as follows:
Similarly, the measurement information being an RSRP is taken as an example to explain that, in the scenario of CA, the first base station schedules each of the user equipments served by the first cell on the specific resource respectively in a round robin (Round Robin RR) scheduling manner. When there are a plurality of transmission powers preset on the specific resource of the second cell, each of the plurality of transmission powers preset by the second base station on the specific resource of the second cell is taken as a current power in turn, the capacity of the first cell corresponding to the current power is calculated, the capacity obtained by each of the user equipments scheduled on the specific resource of the first cell is calculated according to the measurement information of the current cell and the neighboring cells reported by each of the user equipments served by the first cell, respectively, and then the capacity of the first cell corresponding to the current power is calculated according to the capacity obtained by each of the user equipments scheduled on the specific resource of the first cell.
As an optional embodiment, if the user equipment UEn served by the first cell is scheduled on the specific resource of the first cell, the capacity obtained by the UEn on the specific resource of the first cell may be calculated by the following Equation 7:
C
n
(
m
,
x
)
=
log
2
{
1
+
RSRP
i
∑
k
=
0
,
k
≠
m
K
RSRP
k
+
x
*
RSRP
m
}
(
Equation
7
)
In the above Equation 7, C n (m,x) is the capacity obtained by the UEn scheduled on the specific resource of the first cell; RSRP i is an RSRP of the current cell, i.e., the first cell, reported by the UEn; RSRP k is an RSRP of the neighboring cell, in particular, the k-th cell in the third cells, reported by the UEn; RSRP m is an RSRP of the neighboring cell, in particular, the second cell, reported by the UEn; X is the ratio of the current power with respect to the transmission power at which the second base station sends the RS, wherein the current power is one of the configurable eight step values of the transmission power previously described.
After calculating the capacity obtained by each of the user equipments served by the first cell which is scheduled on the specific resource of the first cell according to Equation 7, the first base station adds up the capacity obtained by each of the user equipments served by the first cell on the specific resource of the first cell to get the average value, and obtains the capacity of the first cell corresponding to the current power. As an optional embodiment, in particular, the following Equation 8 may be used to calculate the capacity of the first cell corresponding to the current power:
C
i
Pico
(
m
,
x
)
=
1
N
∑
n
=
0
N
C
n
(
m
,
x
)
(
Equation
8
)
In the above equation 8, C i pico (m,x) is the capacity of the first cell corresponding to the current power; N is the total number of the user equipments served by the first base station, wherein since the user equipment served by base station has been registered in the base station, the first base station is aware of the total number of the user equipments served by the first base station; C n (m,x) is the capacity obtained by the user equipment UEn, served by the first cell, which is scheduled on the specific resource of the first cell.
In implementation of this embodiment, when the measurement information is a CQI, the method for calculating the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell includes: obtaining the frequency spectrum efficiency corresponding to the reported CQI directly according to the CQI reported by the user equipment served by the first cell on the specific resource of the first cell, then processing, e.g. averaging, weightedly averaging, or the like, the frequency spectrum efficiency corresponding to the CQI reported by all the user equipments, to obtain the processed frequency spectrum efficiency of the first cell, and taking it as the capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell.
After that, the first base station may send the calculated capacity information of the first cell corresponding to the transmission power preset by the second base station on the specific resource of the second cell to the power determining device, so that the power determining device determines the transmission power of the second base station on the specific resource of the second cell according to the received capacity information of the first cell. The detailed description about this part refers to the description of steps 203 to 205 , and will not be described redundantly herein.
In specific implementation of an embodiment of the present invention, when the specific resource is a single physical resource block (PRB) or a set of physical resource blocks, the method for determining the transmission power is the same as the method for determining the transmission power in the scenario of CA, and thus will not be described redundantly herein.
With the above-mentioned technical solution provided in the embodiments of the present invention, by the implementation of the technical solution of receiving the capacity information of the first cell sent by the first base station, obtaining the capacity information of the second cell, and then determining the transmission power used by the second base station on the specific resource of the second cell according to the capacity information of the first cell and the capacity information of the second cell, the maximization of the total capacity of the first cell and the second cell can be guaranteed.
As shown in FIG. 3 , the present embodiment provides a method for determining the transmission power, including the following content.
At 301 , a first base station sends capacity information of the first cell to a second base station. The capacity information of the first cell corresponds to a transmission power preset by the second base station on a specific resource of the second cell, the specific resource is a radio resource shared by the first cell and the second cell, and the first capacity information is used by the second base station to determine the transmission power on the specific resource of the second cell.
Specifically, the method for determining the transmission power used on the specific resource of the second cell by the second base station may refer to the above described embodiment, and thus will not be described redundantly herein.
As an optional embodiment, the capacity information of the first cell may be included in load information (e.g. Load Information message) sent to the second base station by the first base station.
As another optional embodiment, before step 301 shown in FIG. 3 , the method may further include: at 300 , the first base station receives capacity request information sent by the second base station. In this case, the above 301 may specifically be: the first base station sends the capacity information of the first cell to the second base station according to the capacity request information. Optionally, the capacity request information may be included in a resource status request message (e.g. Resource Status Request message) sent to the first base station by the second base station; and the capacity information of the first cell may be included in a resource status update message (e.g. Resource Status Update message) sent to the second base station by the first base station.
Furthermore, in the above-mentioned embodiment, the first base station may calculate the capacity information of the first cell according to the transmission power preset by the second base station on the specific resource of the second cell and the measurement information of the first cell and the neighboring cells reported by the user equipment. With the technical solution provided in the above-mentioned embodiment, the second base station sends the capacity information of the first cell to the second base station by the first base station, such that the second base station may determine the transmission power used on the specific resource of the second cell according to the capacity information of the first cell, and thus the capacity of the first cell can be guaranteed.
Another aspect of an embodiment of the present invention provides a power determining device. Referring to FIG. 4 , the power determining device may be the second base station or the control node in the method embodiments, and includes a receiver 401 and a first processor 402 .
The receiver 401 is configured to receive capacity information of a first cell sent by a first base station. The capacity information of the first cell corresponds to a transmission power preset by the second base station on a specific resource of a second cell, the specific resource is a radio resource shared by the first cell and the second cell, and the first processor 402 is configured to determine a transmission power used by the second base station on the specific resource of the second cell according to the capacity information of the first cell received by the receiver 401 and the capacity information of the second cell obtained by the first processor 402 .
In specific implementation of an embodiment of the present embodiment, the first processor 402 is specifically configured to calculate an average capacity of the first cell according to the capacity information of the first cell, and determine the transmission power used by a serving base station of the second cell on the specific resource of the second cell according to the average capacity of the first cell.
Furthermore, the first processor 402 is specifically configured to determine, for the power determining device, the maximum transmission power at which the average capacity of the first cell satisfies a predetermined capacity threshold, and take the maximum transmission power as the transmission power used by the serving base station of the second cell on the specific resource of the second cell.
In specific implementation of an embodiment of the present embodiment, if there are a plurality of transmission powers preset by the serving base station of the second cell on the specific resource of the second cell, then there are a plurality of pieces of capacity information of the first cell which have a one-to-one correspondence with the transmission powers preset by the serving base station of the second cell on the specific resource of the second cell.
With the above-mentioned technical solution provided in the present invention, the power determining device receives the capacity information of the first cell sent by the serving base station of the first cell, and determines the transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell, and thus the capacity of the first cell (i.e. victim cell) can be guaranteed.
Referring to FIG. 5 , as an optional embodiment, the device shown in FIG. 4 may further include: a second processor 403 , which is configured to obtain capacity information of the second cell, and determine the transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell and the capacity information of the second cell; the capacity information of the second cell corresponds to the transmission power preset by the serving base station of the second cell on the specific resource of the second cell.
In specific implementation of an embodiment of the present invention, for the scenario in which the first base station and the power determining device have not pre-negotiated the transmission power preset by the second base station on the specific resource of the second cell, the receiver 401 is further configured to receive information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the first cell, which is sent by the first base station.
In specific implementation of an embodiment of the present invention, for the scenario in which the first base station and the power determining device have not pre-negotiated the transmission power preset by the second base station on the specific resource of the second cell, when the power determining device is a control node, the receiver 401 is further configured to receive information about the transmission power preset by the second base station on the specific resource of the second cell corresponding to the capacity information of the second cell, which is sent by the second base station.
In an embodiment of the present invention, when the power determining device is the control node, the second processor 403 is specifically configured to receive the capacity information of the second cell sent by the second base station. When the power determining device is the second base station, the second processor 403 is specifically configured to calculate the capacity information of the second cell according to the transmission power preset by the second base station on the specific resource of the second cell and measurement information reported by a user equipment served by the second cell.
Referring to FIG. 6 , in an embodiment of the present invention, the second processor 403 as shown in FIG. 5 includes: a calculating unit 4031 , which is configured to calculate total capacity information of the first cell and the second cell according to the capacity information of the first cell and the capacity information of the second cell when there are a plurality of transmission powers preset by the second base station on the specific resource of the second cell, then there are a plurality of pieces of capacity information of the first cell corresponding to the transmission powers preset by the second base station on the specific resource of the second cell, and there are a plurality of pieces of capacity information of the second cell which correspond to the transmission powers preset by the second base station on the specific resource of the second cell, wherein there are a plurality of pieces of total capacity information which correspond to the transmission powers preset by the second base station on the specific resource of the second cell.
In the embodiment depicted in FIG. 6 , the second processor 403 also includes a determining unit 4032 , which is configured to select the maximum total capacity information from the plurality of pieces of total capacity information calculated, and take the power corresponding to the maximum total capacity information as the transmission power used by the second base station on the specific resource of the second cell.
With the above-mentioned technical solution provided in an embodiment of the present invention, by the implementation of the technical solution of receiving the capacity information of the first cell sent by the first base station, obtaining the capacity information of the second cell, and then determining the transmission power used by the second base station on the specific resource of the second cell according to the capacity information of the first cell and the capacity information of the second cell, the maximization of the total capacity of the first cell and the second cell can be guaranteed.
Still another aspect of an embodiment of the present invention provides a base station. Referring to FIG. 7 , the base station may specifically be the first base station in the above-mentioned method embodiments, and may include: a transmitter 501 , which is configured to send capacity information of a first cell to a serving base station of a second cell, wherein the capacity information of the first cell corresponds to a transmission power preset by the serving base station of the second cell on a specific resource of the second cell, the specific resource is a radio resource shared by the first cell and the second cell, and the first capacity information is used by the serving base station of the second cell to determine the transmission power used on the specific resource of the second cell.
As an optional embodiment, the capacity information of the first cell is included in load information sent to the serving base station of the second cell by the serving base station of the first cell.
Referring to FIG. 8 , as another optional embodiment, the base station shown in FIG. 7 can further include a receiver 502 , which is configured to receive capacity request information sent by the serving base station of the second cell.
Accordingly, the transmitter 501 is specifically configured to send the capacity information of the first cell to the serving base station of the second cell according to the capacity request information.
Optionally, the capacity request information is included in a resource status request message sent to the serving base station of the first cell by the serving base station of the second cell, and the capacity information of the first cell is included in a resource status update message sent to the serving base station of the second cell by the serving base station of the first cell.
Furthermore, in the above-mentioned embodiment, the base station may be configured to calculate the capacity information of the first cell according to the transmission power preset by the second base station on the specific resource of the second cell and measurement information of the first cell and a neighboring cell reported by a user equipment. With the technical solution provided in the above-mentioned embodiment, the first base station sends the capacity information of the first cell to the second base station such that the second base station may determine the transmission power used on the specific resource of the second cell according to the capacity information of the first cell, and thus the capacity of the first cell can be guaranteed.
In addition, an embodiment of the present invention still provides a system for determining a transmission power. Referring to FIG. 9 , the system includes: a first base station 601 and a power determining device 602 .
The above first base station 601 is configured to send capacity information of a first cell to the power determining device 602 , the capacity information of the first cell corresponds to a transmission power preset by a second base station on a specific resource of the second cell, and the specific resource is a radio resource shared by the first cell and the second cell; the above power determining device 602 is configured to receive the capacity information of the first cell sent by the first base station, and then determine the transmission power used by the second base station on the specific resource of the second cell according to the capacity information of the first cell.
With the above-mentioned technical solution provided in the present invention, the power determining device receives the capacity information of the first cell sent by the serving base station of the first cell, and determines the transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell, thus the capacity of the first cell (i.e. victim cell) can be guaranteed.
As an optional embodiment, the power determining device 602 is further configured to obtain capacity information of the second cell, wherein the capacity information of the second cell corresponds to the transmission power preset by the serving base station of the second cell on the specific resource of the second cell, and then determine the transmission power used by the serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell and the capacity information of the second cell, to guarantee the maximization of total capacity of the first cell and the second cell.
In an embodiment of the present invention, the power determining device 602 is specifically the second base station or the control node as described in the above-mentioned method embodiments, and the detailed structure thereof may refer to the power determining device shown in FIG. 4, 5 , or 6 , and the detailed structure of the first base station 601 may refer to the base station shown in FIG. 7 and FIG. 8 , and thus will not be described redundantly herein.
The interaction between the devices as described in the embodiments of the present invention, may refer to the description in the above-mentioned method embodiments, and thus will not be described redundantly herein.
It should be appreciated for those skilled in the art that all or a part of the steps in the above-mentioned embodiments may be implemented by hardware, or may be implemented by program instructing relevant hardware. The program may be stored in a computer readable storage medium, and the above-mentioned storage medium may be a read-only memory, a magnetic disk, an optical disk, or the like.
The preceding embodiments are merely preferred embodiments of the present invention, rather than limiting the present invention. All the modification, equivalent substitution, or improvement made within the principle of the present invention should fall within the protection scope of the present invention. | The present invention provides methods and devices for determining a transmission power and relates to the field of communication technologies. A method includes receiving, by a power determining device, capacity information of a first cell sent by a serving base station of the first cell and determining a transmission power used by a serving base station of the second cell on the specific resource of the second cell according to the capacity information of the first cell. The aforementioned method allows the capacity of the first cell to be guaranteed. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The embodiment relates to a dryer and a foreign material removing apparatus thereof.
2. Description of the Related Art
In general, a dryer is an apparatus that dries a dry target by blowing hot wind generated by a heater into a rotary drum to absorb moisture of a drying target (i.e., clothes which has been washed).
The dryer is largely classified into an exhaust type dryer and a condensation type dryer in accordance with a processing scheme of wet air containing moisture generated by drying the drying target. More specifically, the exhaust-type dryer uses a scheme that discharges the wet air discharged from the drum to the outside of the dryer, while the condensation-type dryer use a re-circulation scheme that removes the moisture by condensing the wet air discharged from the drum in a heat-exchanger and thereafter, heats a dry air without moisture again and sends it to the drum.
Meanwhile, since the drum is formed in a rotation type, the drying target housed in the drum shakes in the drum as the drum rotates. In this process, foreign materials contained in the drying target are spread in the air. That is, the foreign materials are included in the air passing through the drum.
The foreign materials contained in the air causes troubles while passing through mechanical components of the dryer. In addition, the foreign materials contained in the air are discharged to the outside of the dryer to injure user's health. Therefore, while the air passing through the drum passes through a filter, the foreign materials should be removed from the air.
In general, the filter is provided at the front portion of the drum and filters the foreign materials contained in the air passing through the drum. When the foreign materials are accumulated in the filter at predetermined levels, circulation of the air is interfered, such that cleaning is required. In general, the filter is removably coupled to the dryer and after a drying cycle is terminated, the user separates and cleans the filter.
In particular, since the foreign materials which are contained in the wet air contain moisture, the foreign materials are damply attached to the filter. In addition, as the drying cycle is performed, when the amount of the moisture contained in the air decreases, the damply wet foreign materials adhere to the filter while being dried.
According to the dryer in the related art, in order to clean the filter to which the foreign materials is adhered, there is a problem in that the cleaning should be by the user effort, such as strongly shaking off the filter.
If the state where the foreign materials adhere to the filter is ignored, proper wind quantity is not secured. As a result, since the air heated by the heater is not cooled, there is a risk of fire.
In addition, since the filter cleaning operation should be performed whenever using the dry in order to secure the wind quantity in the dryer and prevent firing, it is troublesome to the user.
SUMMARY OF THE INVENTION
The embodiment proposes to solve the above-mentioned problems. An object of the present invention is to provide a dryer including a filter to more facilitate cleaning and a foreign material removing apparatus thereof.
In addition, another object of the present invention is to provide a dryer that automatically clean a filter without manually cleaning the filter and allows the user to separate and discharge the foreign materials removed from the filter and a foreign material removing apparatus thereof.
Further, yet another object of the present invention is to provide a dryer that maintains wind quantity at a predetermined level to improve drying performance without a risk of firing and a foreign material removing apparatus.
In order to achieve the above objects, a dryer according to an embodiment of the present invention includes: a cabinet that forms an exterior; a drum that is provided in the cabinet and houses a drying target; a base that has a rotation motor rotating the drum and a blowing fan moving air in the drum; a drum cover that is coupled to the base and supports the drum; a case in which an air introduction hole that is mounted on the drum cover and into which air discharged from the drum is introduced and an air discharge hole that discharges air without foreign materials are formed; and a filtering unit that is separately mounted on the case and filters the foreign materials in the introduced through the introduction hole, wherein the filtering unit includes a filter member in which a plurality of parts folded based on the curved portion are provided.
A foreign material removing apparatus of a dryer according to another embodiment includes: a case that includes an air introduction hole into which air discharged from a drum is introduced and an air discharge hole that discharges air introduced through the air introduction hole from which foreign materials are separated; a filter member that is mounted on the case to filter the foreign materials from air and is provided with a plurality of parts; a curved portion that connects the plurality of parts and can relatively rotate the plurality of parts; and a guide part that extends along at least one side of the filter member and guides the rotation of the plurality of parts.
A dryer according to yet another embodiment of the present invention includes: a drum that houses a drying target; a base that includes a rotation motor that is provided on one side of the drum and rotates the drum and has a blowing fan that moves air; a foreign material removing apparatus that filters foreign materials from air moved by the operation of the blowing fan and cleans the filtered foreign materials; and a foreign material case that is provided on one side of the foreign material removing apparatus and stores the foreign materials cleaned in the foreign material removing apparatus, wherein the foreign material removing apparatus includes a filter member that separates the foreign materials from air and perform a folding movement; a filter case that movably supports the filter member; and a guide groove that is provided on one side of the filter case and guides the folding movement of the filter member.
With the dryer and the foreign material removing apparatus according to the present invention, it can clearly remove the foreign materials adhered to the filter only by the simple operation without using the user effort.
In addition, the filter is provided in a folded type and is automatically operated by the driving unit, thereby making it possible to effectively remove the foreign materials adhered to the filter. Therefore, the product image is luxurious and the satisfaction of user is increased.
Moreover, the convenience of user can be maximized by separating and cleaning only the case when the foreign materials are stored in the case above a predetermined amount without the user needing to clean the filter each time the dryer is used.
Further, since the wind quantity passing through the inside of the drum is secured at a predetermined level or more while the filter is automatically cleaned, there is no risk of firing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing an exterior of a dryer according to the embodiment of the present invention.
FIG. 2 is an exploded perspective view showing main internal components of a dryer according to a first embodiment of the present invention.
FIG. 3 is an exploded perspective view showing components of a foreign material removing apparatus of FIG. 2 .
FIG. 4 is a side view showing a curved part of a filter member of FIG. 3 .
FIG. 5 is a side view showing an appearance before the filter member of FIG. 3 is curved.
FIG. 6 is a side view showing an appearance after the filter member of FIG. 3 is curved.
FIG. 7 is a perspective view showing a filter member of a dryer according to a second embodiment of the present invention.
FIG. 8 is a perspective view showing a filter member of a dryer according to a third embodiment of the present invention.
FIG. 9 is a side view showing an appearance before the filter member of FIG. 8 is curved.
FIG. 10 is a side view showing an appearance after the filter member of FIG. 8 is curved.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific preferred embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is understood that other embodiments may be utilized and that logical structural, mechanical, electrical, and chemical changes may be made without departing from the spirit or scope of the invention. To avoid detail not necessary to enable those skilled in the art to practice the invention, the description may omit certain information known to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims.
FIG. 1 is a perspective view showing an exterior of a dryer according to a first embodiment of the present invention.
Hereinafter, a condensation-type dryer described as an embodiment in order to describe the spirit of the present invention. However, it is to be noted that the spirit of the embodiments is not limited to the condensation-type dryer and is applicable even to an exhaust-type dryer.
Referring to FIG. 1 , a dryer 10 according to the first embodiment of the present invention includes a cabinet 100 forming an exterior thereof and having an opening part 110 formed on a front surface thereof and a door 120 that is rotatably connected to one side of the cabinet 100 and selectively opens and closes the opening part 110 .
The inside of the cabinet 100 is provided with a drum 200 (see FIG. 2 ) that receives a moisture containing drying target. The drying target can be input into the drum 200 through the opening part 110 .
The door 120 is provided with a transparent window 121 . The user can view the inside of the drum 200 to confirm the drying state in the state where the door 120 is closed.
A control unit 140 that can control a cycle of the dryer 10 is provided on one side of the cabinet 100 . A display unit that displays an operation condition of the dryer and a plurality of buttons that can be operated by the user are included in the control unit 140 .
A drawer 130 that stores condensed water that is generated in the drying process of the drying target is provide on the front surface of the cabinet 100 . When the condensed water is stored in the drawer 130 above a predetermined level, the user can draw out the drawer 130 to drain the condensed water.
A lower cover 150 is removably provided on the front lower portion of the cabinet 100 . The lower cover 150 plays a role of covering a heat exchanger 260 (see FIG. 2 ) cooling air that circulates in the dryer 10 so that the heat exchanger 260 is not viewed from the outside. The user separates the lower cover 150 from the cabinet 100 and thereafter, draws out the heat exchanger 260 for cleaning.
Meanwhile, a foreign material removing apparatus 300 removing the foreign materials contained in the air passing through the drum 200 is provided on the front of the drum 200 . Hereinafter, the detailed configuration thereof will be described.
FIG. 2 is an exploded perspective view showing main internal components of a dryer according to the first embodiment of the present invention.
Referring to FIG. 2 , the cabinet 100 includes the drum 200 housing the drying target, a drum cover 210 that is coupled to the front surface of the drum 200 to support the drum 200 , a rotation motor 221 that is provided in a lower portion of the drum 200 to rotate the drum 200 , a blowing fan 222 that is connected to the rotation motor 221 to circulate the air in the drum 200 , and a base 220 on which the rotation motor 221 and the blowing fan 222 are mounted.
More specifically, the drum 200 has a cylindrical shape of which the front surface and the rear surface are opened and the front surface of the drum 200 is disposed to face the opening part 110 . The front surface of the drum 200 is rotatably connected to the drum cover 210 . A felt, etc., is provided in the drum cover 210 that is in contact with the drum 200 to allow the drum 200 to smoothly rotate.
The drum cover 210 supports the drum 200 and is coupled with the front end portion of the base 220 . The drum cover 210 is formed with an input hole 211 into which the drying target is input. The input hole 211 may be punched to correspond to the opening part 110 and the front surface of the drum 200 .
When the user opens the door 120 and inputs the drying target through the opening part 110 , the drying target is housed in the drum 200 while passing through the input hole 211 .
In addition, an air duct 215 is provided on the lower side of the input hole 211 so that air passing through the drum 200 can be circulated. The foreign material removing apparatus 300 is mounted on the air duct 215 to clean the foreign materials. A foreign material removing cover 250 is connected to the lower portion of the air duct 215 . The detailed description thereof will be described.
The base 220 is configured to form the bottom surface of the dryer 10 and support the drum 210 and the drum 220 .
The rotation motor 221 is provided at an approximately central portion of the base 220 and can be connected to the drum 200 by a belt member (not shown). The drum 200 can be rotated by the driving of the rotation motor 221 .
The blowing fan 222 may be rotatably connected to the rotation motor 221 and may be provided at the front portion of the motor 221 . A cooling fan 223 that is driven by the rotation motor 221 and sucks the external air is provided at the rear portion of the rotation motor 221 . The external air sucked by the cooling fan 223 is heat-exchanged in the heat exchanger 260 .
Although not shown in the drawings, a heater, which heats air introduced into the drum 200 , is provided on the rear portion of the drum 200 .
The heat exchanger 260 that performs the heat exchange between the air which circulates in the drum 200 and the air introduced from the outside of the dryer 10 to exchange heat is provided in one side of the base 220 .
The heat exchanger 260 is provided to be drawn out and in from the front portion of the base 220 so that the user can draw out the heat exchanger 260 and clean it. The detailed operation of the heat exchanger 260 will be described below.
In addition, the foreign material removing apparatus cover 250 is removably provided on the front portion of the base 220 . The foreign material removing apparatus cover 250 is provided on the lower portion of the drum cover 210 and is connected to the lower end portion of the air duct 215 .
In detail, the insertion groove 251 into which the foreign material removing apparatus 300 can be inserted is formed to be depressed in the upper end portion of the foreign material removing apparatus cover 250 . The insertion groove 251 is connected to the lower end portion of the air duct 215 . Therefore, when the foreign material removing apparatus 300 is inserted into the air duct 215 , at least a part of the foreign material removing apparatus 300 is inserted into the insertion groove 251 .
The insertion groove 251 extends to the front portion of the blowing fan 222 . A communicating hole 252 , which moves air to the blowing fan 222 , is formed in the insertion groove 251 The air, which passes through the drum 200 , is introduced into the air duct 215 and can be moved to the blowing fan 222 while passing through the foreign material removing apparatus 300 and the insertion groove 251 .
The foreign material case 390 in which the foreign materials are stored and a foreign material case housing part 255 to which the foreign material case 390 is removably coupled are provided on one side of the foreign material removing apparatus cover 250 . The foreign materials can be input in the foreign material case 390 through the opened upper surface.
The foreign material case housing part 255 is depressed to the rear portion to correspond to the shape of the foreign material case 390 . The hook 256 , which is locked to the foreign material case 390 , is provided on the bottom surface of the foreign material case housing part 255 .
A foreign material dropping hole 253 is formed on the foreign material removing apparatus cover 250 so that the foreign materials dropping from the foreign material removing apparatus 300 can be housed in the foreign material case 390 .
More specifically, a foreign material discharge hole 314 (see FIG. 3 ) is formed on the bottom surface of the foreign material removing apparatus 300 and the foreign material dropping hole 253 is disposed at a position corresponding to the foreign material discharge hole The foreign materials separated from the foreign material removing apparatus 300 is input to the foreign material case 390 and the foreign material case 390 while passing through the foreign material dropping hole 253 .
When the foreign materials stored in the foreign material case 390 is filled at a predetermined level or more, the foreign material can be discharged by separating the foreign material case 390 .
When the foreign materials stored in the foreign material case 390 is filled at a predetermined level or more, the foreign material can be discharged by separating the foreign material case 290 .
In another embodiment, a part of the foreign material removing apparatus 300 can be configured to be protruded to the lower portion of the foreign material dropping hole 253 . In this case, since the lower end portion of the foreign material removing apparatus 300 is housed in the foreign material case 390 , the foreign materials dropping from the foreign material removing apparatus 300 can prevent the leakage to the outside.
Further, the foreign material removing apparatus cover 250 can be formed to shield the inlet and outlet of the heat exchanger 260 in order to sufficiently secure the size of the filter member 500 to be described later. In this case, the heat exchanger 260 can be drawn out after the lower cover 150 and the foreign material removing apparatus 250 are removed.
Meanwhile, since the driving to et contains a large amount of moisture, when dry hot wind passes through the drying target, the moisture contained in the drying target evaporates and spreads to the air. The evaporation process is executed at the same time when the drum 200 rotates and the drying target is dried by being rotated with the drum 200 .
At this time, foreign materials such as dust, naps, etc. contained in the drying target spread to the air. The foreign materials are included in the air that passes through the drum 200 . When the foreign materials are introduced into the blowing fan 222 , etc., the fault of the blowing fan 220 can occur, such that the foreign materials can be filtered before passing through the blowing fan 222 .
The foreign material removing apparatus 300 is mounted on the drum cover 210 , such that air passing through the drum 200 can be removed from the foreign materials.
In detail, when the foreign material removing apparatus 300 is mounted to the low part from the upper portion of the air duct 215 and at least a part of the foreign material removing apparatus 300 is inserted into the insertion groove 251 .
The air, which passes through the drum 200 , is introduced from the upper side of the foreign material removing apparatus 300 and after the foreign material is filtered, is discharged to the front portion of the foreign material removing apparatus 300 . At this time, the front portion of the foreign material removing apparatus 300 can be disposed to be spaced from the drum cover 210 and the inner side surface of the insertion groove 251 so that air smoothly flows in the drum cover 210 and the insertion groove 251 .
The operation of the dryer 10 having the above-mentioned configuration will be described below.
The dryer 10 is a condensation-type dryer and is operated in a scheme that the air (a dotted line arrow of FIG. 2 , hereinafter, circulation air) circulating in the dryer 10 is cooled by the air (a solid line arrow of FIG. 2 , hereinafter, cooling air) introduced from the outside of the dryer 10 .
In detail, the circulation air in the drum 200 includes a large quantity of moisture containing foreign materials. The circulation air moves forward by the rotation of the blowing fan 222 and is discharged from the drum 200 and passes through the foreign material removing apparatus 300 . In this process, the foreign materials included in the circulation air are filtered by the filter member 500 to be described later.
The circulation air, which passes through the foreign material removing apparatus 30 , moves to the heat exchanger 260 through the blowing fan 22 and can be cooled by being heat-exchanged with the cooling air. In the heat exchange process, the condensed water, which is condensed from the circulation air, moves to the drawer 130 and is discharged.
The cooled circulation air moves to the rear portion of the base 220 and is heated at high temperature by the heater. The heated air is introduced into the drum 200 again and circulates in the dryer 10 .
Meanwhile, the cooling air is sucked into the base 220 from the rear portion of the drier 10 by the rotation of the cooling fan 223 . The cooling air moves to the heat exchanger 260 along the passage formed in the base 220 and can be heat-exchanged with the circulation air. The cooling air with an increased temperature in the heat exchange process is discharged to the front or side of the drier 10 .
Hereinafter, the configuration and operation of the foreign material removing apparatus 300 will be described with reference to the drawings.
FIG. 3 is an exploded perspective view showing components of a foreign material removing apparatus of FIG. 2 , FIG. 4 is a side view showing a curved part of a filter member of FIG. 3 , FIG. 5 is a side view showing an appearance before the filter member of FIG. 3 is curved, and FIG. 6 is a side view showing an appearance after the filter member of FIG. 3 is curved.
Referring to FIG. 3 to 6 , the foreign material removing apparatus 300 includes a first case 310 in which an air introduction hole 311 is formed, a second case 320 in which an air discharge hole 321 is formed, and a filtering unit 400 that is provided in a space between the first case 310 and the second case 320 and filters the foreign materials in the air introduced through the air introduction hole 311 .
However, the first case 310 and the second case 320 may be integrally injection-molded. Unlike one shown in the drawings, the air introduction hole 311 may be formed in the second case 320 and the air discharge hole 321 may be formed in the first case 310 .
The first case 310 faces the rear portion of the dryer 10 and the second case 320 is inserted to face the front portion of the dryer 10 , in the state where the foreign material removing apparatus 300 is inserted into the drum cover 210 .
In other words, the first case 310 is disposed to face the rear portion of the dryer 10 so that it faces the drum 200 and the air discharged from the drum 200 may be introduced into the air introduction hole 311 through the air duct 215 .
In detail, the air introduction hole 311 is a part into which air discharged from the drum 200 is introduced and is formed on the upper part of the first case 310 to be tilted at a predetermined angle. The air discharged from the drum 200 may be input at an acute angle with respect to a horizontal surface. The air introduction hole 311 is provided in a grill shape, such that it can prevent the drying target from inputting to the inside of the foreign material removing apparatus 300 .
In detail, the air introduction hole 311 is a part into which air discharged from the drum 200 is introduced and is formed on the upper par of the first case 310 to be tilted at a predetermined angle. The air discharged from the drum 200 may be input at an acute angle with respect to a horizontal surface. The air introduction hole 311 is provided in a grill shape, such that it can prevent the drying target from inputting to the inside of the foreign material removing apparatus 300 .
Since the air introduction hole 311 is provided to be tilted, the air discharged from the drum 200 flows while forming a predetermined angle with respect to the filtering unit 400 .
The foreign material discharge hole 314 , which separates the foreign materials from the filtering unit 400 and is discharged, is formed on the bottom surface of the first case 310 . The foreign material discharge hole 314 is positioned at the front side of the surface that filters the foreign materials of the filtering unit 400 , such that it is formed to smoothly discharge the separated foreign materials.
A handle groove 312 may be formed on the upper end portion of the first case 310 so that the user can easily hold a removable handle 420 of the filtering unit 400 .
The air discharge hole 321 , which discharges air passing through the filtering unit 400 , is formed in the second case 320 . The air discharge hole 321 is formed in an approximately rectangular shape and is formed at a sufficient size so that the wind quantity, which circulates in the dryer 10 , can be secured above a predetermined level.
In addition, a guide rib 325 , which guides the coupling of the filtering unit 400 , is provided at both sides of the second case 320 . The filtering unit 400 may be inserted downwardly to face a space between the second case 320 and the guide rib 325 .
The guide rib 325 supports the front portion of the filtering unit 400 in the state where the filtering unit 400 is coupled thereto and the filtering unit 400 can be closed to the second case 320 .
In the state where the filtering unit 400 is coupled to one side of the guide rib 325 , the air discharge hole 321 can be shielded. The air introduced through the air introduction hole 311 can pass through the filtering unit 400 and be discharged to the air discharge hole 321 . The foreign materials discharged through the foreign material discharge hole 314 can be stored in the foreign material case 390 .
The filtering unit 400 includes, a filter case 410 , an air hole 430 that is formed in the filter case 410 in a punched form and is formed to correspond to the shape of the air discharge hole 321 , a filter member 500 that is formed to shield the air hole 430 and filters the foreign materials, and a guide part 450 that guides the curve of the filter member 500 .
In detail, the filter case 410 is configured to be inserted into the second case 320 .
A removable handle 420 is provided on the upper end portion of the filter case 410 so that the user can easily hold the filter case 410 to separate the filtering unit 400 from the foreign material removing apparatus 300 . The removable handle 420 may be disposed at a position corresponding to the removable handle groove 312 when the filter case 410 is coupled with the second case 320 .
The filter case 410 includes the air hole 430 that is formed at a position corresponding to the air discharge hole 321 when the filter case 410 is coupled with the second case 320 . The air hole 430 is shielded by the filter member 500 and the air passing through the filter member 500 moves to the air discharge hole 321 through the air hole 430 .
The guide part 450 , which guides the curve of the filter member 500 , extends up and down at both sides of the air hole 430 . The up and down direction may be a direction that is defined corresponding to the configuration that the filter member 500 moves (folds) up and down.
In detail, the guide part 450 is formed to be protruded by a predetermined length from the filter case 410 . The guide part 450 is formed with a guide groove 451 that is depressed downwardly. The upper end portion of the guide groove 451 is formed with the insertion part 455 opened so that the filter member 500 can be inserted. The filter member 500 is inserted to the lower portion from the upper portion of the insertion part 455 .
The guide groove 451 extends from the lower portion of the insertion part 455 to the lower end portion of the guide part 450 and the filter member 500 may be inserted up to the lower end portion of the guide part 450 along the guide groove 451 . At this time, the guide groove 451 is formed at a position spaced by a predetermined distance from the filter case 410 so that the filter member 500 is closely coupled to the filter case 410 .
The upper end portion and lower end portion of the guide groove 451 are formed with an upper hooking groove 452 and a lower hooking groove 453 , respectively, so that they are disposed to be intersected with the extending direction of the guide groove 451 . The upper end portion and lower end portion of the filter member 500 can be inserted into the hooking grooves 452 and 453 , respectively, such that the filter member 450 may be maintained in an unfolded state.
Meanwhile, the filter member 500 is formed so that the plurality of parts are relatively curved to each other. At this time, it is preferable that the parts are provided in an even number so that the filter member 500 can be curved the state where the filter member 500 is coupled with the guide part 450 . In the embodiment, the case where the filter member 500 is configured in four parts will be described by way of example.
The filter member 500 includes a first part 510 that is provided on the uppermost side, a second part 520 that is connected to the lower portion of the first part 510 , a third part 530 that is connected to the lower portion of the second part 520 , and a fourth part 540 that is connected to the third part 530 and is provided on the lowermost side.
Each of the first, second, third, and fourth parts 510 , 520 , 530 , and 540 can be configured by one that the filter 570 is attached to the frame 512 . The frame 512 has an approximately rectangular shape and the central portion of the frame 512 is punched. The filter 570 is configured to filter the foreign materials.
At this time, the filter 570 is formed so that all the filters provided to each of the part 510 , 520 , 530 , and 540 can be connected, thereby better separating the foreign materials. The detailed contents thereof will be described below.
A fixing projection 517 , which moves up and down while being inserted into the guide groove 451 , is formed at both sides of the upper end portion of the first part 510 and the lower end portion of the fourth part. The fixing projection 517 may extend to the outer side of the guide part 450 .
The fixing projection 517 is coupled to a fixing member 550 . The fixing member 550 is coupled at both sides of the first part 510 and the fourth part 540 and the filter member 500 can be coupled to the filter case 410 by the fixing member 550 . The filter member 500 is fixed to the guide part 450 by inserting the fixing projection 517 into the hooking grooves 452 and 453 .
A filter handle 515 is provided on the upper end portion of the first part 510 . The filter handle 515 is coupled to the upper end portion of the first part 510 by a hinge and can be configured to be rotated according to the degree of pulling the filter handle 515 by the user.
Meanwhile, each part 510 , 520 , 530 , and 540 is connected to each other by curved parts 581 , 582 , and 583 .
The curved parts, which are formed on the upper side and the lower portion of one of the parts 510 , 520 , 530 , and 540 , are disposed not to be positioned on the same line in a vertical direction. Therefore, when the user holds the filter handle 515 and pulls it down, the filter member 500 is folded as becoming wrinkled and in this process, the foreign materials that are filtered in the filter member 500 can be removed.
In detail, the rear edge of the lower end portion of the first part 510 is protruded downwardly by a predetermined length, such that it is connected to a portion protruded by a predetermined length from the rear edge of the upper end portion of the second part 520 . The connection portion can be thinly formed to be folded.
At this time, the connection portion forms the first curved part 581 . Since the first curved part 581 is provided at the rear portions of the first and second parts 510 and 520 , the first part 510 can be relatively rotated clockwise with respect to the second part 520 based on the first curved part 581 (see FIG. 6 ).
The front edge of the lower end portion of the second part 520 is protruded by a predetermined length downwardly, such that it is connected to the portion protruded by a predetermined length from the front edge of the upper end portion of the third part 530 .
At this time, the connection portion forms the second curved part 582 . Since the second curved part 582 is provided at the front portions of the first and second parts 520 and 530 , the second part 510 can be relatively rotated counterclockwise with respect to the third part 530 based on the second curved part 582 (see FIG. 6 ).
In summary, the first curved part 581 is disposed to face the rear portion of the second part 520 and the second curved part 582 is disposed to face the front portion of the second part 520 . In other words, the first curved part 581 and the second curved part 582 are disposed to face each other. The first part 510 may be rotated clockwise by the arrangement and the second part 510 may be rotated counterclockwise.
The configuration of the third curved part 583 between the third part 530 and the fourth part 540 is similar to the configuration of the first curved part 581 and the third part 530 can be relatively rotated clockwise with respect to the fourth part 540 based on the third curved part 583 (see FIG. 6 ). Similarly, the second curved part 582 and the third curved part 583 are disposed to face each other.
The above-mentioned curved part is alternately disposed in a front and rear direction of each part 510 , 520 , 530 , and 540 , such that each part 510 , 520 , 530 , and 540 is sequentially rotated in different directions (clockwise or counterclockwise direction). Consequently, the filter member 500 is operated to be folded as becoming wrinkled while each part 510 , 520 , 530 , and 540 are rotated.
Consequently, the length of the filter member 500 in the folded state is formed to be smaller than the filter member 500 in the unfolded state. In the embodiment, when the filter member 500 is folded up and down, the length of the up and down direction of the filter member 500 can be reduced during the folding process. On the other hand, in embodiments as will be described later, when the filter member 500 is folded left and right, the length of the left and right direction of the filter member 500 can be reduced during the folding process.
At this time, since the fixing projection 517 moves in the state where it is inserted into the guide groove 451 , the filter member 500 can be folded only in a predetermined direction. In addition, since the filter member 500 is folded in the state where it is coupled with the filter case 410 , the user can conveniently clean the filter member 500 .
Meanwhile, adjacent filters of each of the part 510 , 520 , 530 , and 540 are closely disposed in the state where the filter member 500 is unfolded. In other words, the filter, which is provided in one part and the filter, which is provided in the adjacent part are closely formed, such that a filter, which is substantially plane to the filter member 500 , can be obtained.
For example, the filter 570 can be attached to extend to the adjacent parts while passing through the curved parts 581 , 582 , and 583 from the front surface of each part 510 , 520 , 530 , and 540 .
The function and operation of the filter member 500 will be described below.
The air introduced through the air introduction hole 311 passes through the filtering unit 400 and is discharged to the air discharge hole 321 . In this process, the foreign materials included in the air are filtered in the filtering unit 400 .
Air necessarily passes through the filter member 500 in the state where the filter member 500 and the air hole 430 are shielded, such that the foreign materials can be easily filtered by the filter 570 .
The filters 570 attached to each part 510 , 520 , 530 , and 540 are closely formed to each other, such that the foreign materials can be filtered at boundary portions of each part 510 , 520 , 530 , and 540 .
Meanwhile, at the early state of the drying cycle, the foreign materials are collected in the filter surface of the filter member 500 together with moisture while a large quantity of moisture containing air is filtered. Thereafter, when air, which is gradually dried according to the progress of the drying cycle, passes through the filter member 500 , a coagulation phenomenon that the collected foreign materials are firmly adhered to the filter member can occur. In particular, the foreign materials may be adhered to the curved parts 581 , 582 , and 583 .
After the drying cycle is terminated, the user separates the filtering unit 400 from the foreign material removing apparatus 300 . The user can open the door 120 and separate the filtering unit 400 by using the removable handle 420 that is exposed to the outside.
After the filtering unit 400 is separated, the user pulls the filter handle 515 forward, such that the fixing projection 517 of the first part 510 is separated from the upper hooking groove 452 . Thereafter, when the user pulls the filter handle 515 downward, the filter member 500 becomes wrinkled by being curved based on the curved parts 581 , 582 , and 583 .
When the filter member 500 becomes wrinkled, the adhered foreign materials can be separated from the filter member 500 based on the position corresponding to the curved parts 581 , 582 , and 583 . If necessary, the folding operation to wrinkle the filter member 500 can be repeatedly performed as described above.
Pieces of the separated foreign materials are stored in the foreign case 390 and the user removes the foreign materials of the foreign case 390 , such that the cleaning of the filtering unit 400 can be finished.
Consequently, the hardened foreign materials are separated from the filter member 500 and can be cleaned by the operation of pulling the filter handle 515 by the user, thereby making it possible to increase the convenience of use.
Hereinafter, a dryer according to the second embodiment of the present invention will be described with reference to the drawings. However, since the second embodiment has the difference in the direction that the filter is folded as compared to comparing the first embodiment, the difference will mainly be described and the same components thereof recites the description and reference numerals of the first embodiment.
FIG. 7 is a perspective view showing a filter member of a dryer according to a second embodiment of the present invention.
Referring to FIG. 7 , the guide unit 450 is formed on the upper portion and lower portion of the air hole 430 to extend in a left and right direction.
The left and right portions of the guide part 450 are provided with the insertion part 455 in which the filter member 500 is inserted and the guide groove 451 that extends to a horizontal direction from the insertion part 455 . One end portion and the other end portion of the guide groove 451 are each formed with the hooking grooves 452 and 453 .
The filter member 500 is inserted into the insertion part 455 in a horizontal direction and the fixing projection 517 is inserted into the hooking groove 452 , such that the filter member is fixed to the filter case 410 . The user holds the filter handle 515 and applies force thereto to pull it in a horizontal direction, such that the coagulated foreign materials adhered to the filter member can be broken and removed.
In this case, since the curved parts 581 , 582 , and 583 lengthily extend up and down and the filter member 500 is folded to be wrinkled in a left and right direction, the foreign materials separated from the surface of the filter 270 is easy to drop in a down direction that is a gravity direction. That is, the foreign materials can be better separated from the surface of the filter 270 .
In summary, the filter member 500 of the first embodiment is inserted into the filtering unit 400 up and down (vertically) and thus, is disposed to be folded up and down, while the filter member 500 according to the embodiment is inserted into the filtering unit 400 in a left and right (horizontal) direction and thus is disposed to be folded left and down.
Hereinafter, a dryer according to a third embodiment of the present invention will be described with reference to the drawings. However, since the third embodiment has difference in a configuration that the filter is automatically folded as compared to comparing the first embodiment, the difference will mainly be described and the same components thereof recites the description and reference numerals of the first embodiment.
FIG. 8 is a perspective view showing a filter member of a dryer according to a third embodiment of the present invention, FIG. 9 is a side view showing an appearance before the filter member of FIG. 8 is curved, and FIG. 10 is a side view showing an appearance after the filter member of FIG. 8 is curved.
Referring to FIG. 8 to 10 , a driving unit 480 is provided on the lower portion of the air hole 430 so that the filter member 500 can be automatically folded.
In detail, the driving unit 480 includes a driving motor 482 , a motor supporting part 481 that is protruded from the filter case 410 and supports the driving motor 482 , and a pulley 483 that is connected to the rotation shaft of the driving motor 482 . The driving motor 482 may be disposed so that the pulley 483 is positioned in a vertical direction of the filter case 410 .
The pulley 483 is connected to a wire 460 . The wire 460 is fixed to the upper end portion of the first part 510 while passing through the space between the filter member 500 and the filter case 410 . The pulley 483 and the wire 460 can be considered as a “power transfer unit” that transfers the driving force of the driving motor 482 to the filter member 500 .
In detail, the upper end portion of the first part 510 is provided with a hooking part 511 that is protruded from the first part 510 and is curved at least once. The wire 460 may be hooked to the hooking part 511 .
The filter case 410 is provided with a direction changing pulley 487 that changes the direction of the wire. The direction changing pulley 487 is disposed to be spaced by a predetermined distance from the filter case 410 so that the wire 460 extended from the pulley 483 can pass through the space between the filter member 570 and the filter case 410 without interfering with the filter member 570 , etc. The direction changing pulley 487 may be fixed to the filter case 410 by the pulley supporting part 486 .
The filter member 500 may be folded by the driving of the driving motor 482 .
In detail, when the pulley 483 is rotated, the wire 460 is wound on the pulley 483 . Therefore, a downwardly pulled force is applied to the first part 510 and in this process, the filter member 500 is folded. At this time, since the fixing projection 517 drops along the guide groove 451 and the filter member 500 can be folded in a predetermined direction.
Meanwhile, the upper part of the filter member 500 is provided with an elastic member 470 that returns the filter member to an original state from the state where the filter member 500 is folded. The elastic member 470 includes a tension spring. However, the elastic member 470 is not limited to the tension spring and other elastic body, which provides a restoring force, can be used. The embodiment will describe the tension spring by way of example.
In detail, the elastic member 470 is fixed to the fixing part 415 whose one side is fixed to the hooking part 511 and the other side is formed on the upper side of the filter case 410 .
The elastic member 470 is in the state where the external force is not applied when the filter member 500 is unfolded, that is, the state where the elastic deformation does not occur.
On the other hand, when the filter member 500 is folded, the elastic member 470 is extended and applies the restoring force upward. The size of the restoring force is proportional to the degree that the elastic member 470 is folded by a Hook's law.
When the filter member 500 is folded and thus, the coagulated foreign materials reach a separated state, the operation of the driving motor 482 stops. The operation time of the driving motor 482 can be previously set.
When the operation of the driving motor 482 stops, the filter member 500 is unfolded in an original state by the restoring force of the elastic member 470 . In this process, the pulley 483 is rotated in an opposite direction when the filter member 500 is folded and the wire 460 is released.
As described above, when the operation of the driving motor 482 and the restoring process by the elastic member 470 are repeated, the foreign materials adhered to the filter member 500 can be better separated and discharged.
The foreign materials separated from the filter member 500 are stored in the foreign material case 390 through the foreign material discharge hole 314 by the above-mentioned process.
When the foreign materials are stored in the foreign case 390 above a predetermined level, the user separates only the foreign material case 390 and throws out the foreign materials and then mounts the foreign material case 390 again.
Since the foreign materials are automatically cleaned, the foreign materials are not accumulated in the filter 570 and thus, the wind quantity in the dryer 10 can be always maintained at a proper level or more. At this time, the above-mentioned process of cleaning foreign materials can be performed at the time point when the foreign materials is completely coagulated to be easily broken, that is, at the time point when the drying cycle is terminated or after the drying cycle is terminated.
With the foreign material removing apparatus 300 having the above-mentioned configuration, the convenience of use is maximized since the user does not need to clean the filter each time the drying operation is performed.
Further, the product image is luxurious and the satisfaction of user is increased since the foreign materials are automatically removed.
In addition, since the user separates only the foreign material case 390 and throws out the foreign materials therein, he and she can conveniently use the drier 10 .
Moreover, since the wind quantity passing through the inside of the drum is maintained at a predetermined level or more by automatically performing the process of removing the foreign materials, there is no risk of firing. | A dryer and a foreign material removing apparatus thereof are provided. The dryer and the foreign material removing apparatus can clearly remove foreign materials adhered to a filter using only a simple operation without the user effort. | 3 |
BACKGROUND OF THE INVENTION
This is a continuation of application Ser. No. 341,049, filed Mar. 14, 1973, now abandoned.
1. Field of the Invention
The present invention relates generally to interconnects for integrated circuits and more particularly to the fabrication of a combination molybdenum and aluminum interconnect system.
2. Prior Art
A major product of the semi-conductor industry is integrated circuits formed of planar semiconductor devices in a substrate of silicon. Generally, a silicon oxide or glass coating overlies the silicon substrate, except in the actual contact areas. This coating functions to pacify the junctions and provide an insulation between the devices and the interconnects. Accordingly, the contact metal material must exhibit good adherence to the silicon and to the silicon oxide or glass, while not producing any undesirable reaction with -- nor penetration of -- the silicon or the oxide.
A metal interconnect system for integrated circuits must make a low resistance, non-rectifying contact to all types of silicon and must not react substantially with the silicon at moderate temperatures (500°C.). Aluminum has been found most suitable for use as interconnect with silicon planar devices in integrated circuits. Aluminum is an excellent conductor and adheres well to silicon and silicon oxide. It is also easily applied to semiconductor devices by evaporation and photoresist techniques and contacts made of aluminum are readily bondable with gold or aluminum wires.
Though aluminum has many excellent qualities and is widely used in the industry, it also has a variety of disadvantages. Specifically, aluminum and silicon greatly interfuse at 500°C. and since aluminum is a P type dopant, it can form a PN rectifying junction with the N type silicon. Thus, aluminum does not make a good ohmic contact with N type silicon.
In a high frequency double-diffused NPN transistor, the emitter region is typically diffused into the base region to a very shallow depth of only about 1,500 to 2,000 angstroms. Due to the small geometry of the shallow double-diffused transistor, the edge of the emitter diffusion opening in the oxide mask layer is so close to the emitter-base junction at the surface of the wafer that horizontal migration of the interaction between the aluminum and the silicon formed during the alloying process of the aluminum at approximately 500°C. often shorts out the base-emitter junction as well as vertical migration, which may also short out the emitter-base junction.
The prior art tries to avoid the above problems by using different contact metals wherein possibly one of the layers is aluminum because of its good contact with exterior metal wire. Some metal systems even use molybdenum in direct contact with P- silicon, but molybdenum does not form a low resistance contact with all types of silicon.
SUMMARY OF THE INVENTION
In order to retain the advantages of using aluminum while minimizing the disadvantages, this invention forms the metal interconnect system having molybdenum in contact with all N type contact areas and aluminun in contact with the molybdenum and with all P type contact areas. The combined molybdenum-aluminum interconnect system makes low resistance, non-rectifying contacts with the doped silicon while not reacting substantially with the silicon at moderate temperatures.
Accordingly, it is a principal object of the present invention to provide an improved metal interconnect system for planar doped silicon semiconductor devices in integrated circuits.
Another object of the present invention is to provide an interconnect system using aluminum having low resistance, non-rectifying contacts with the silicon.
A still further object of the present invention is to provide an aluminum interconnect system which will not substantially react with the silicon in shallow diffused N type emitter regions at moderate temperatures so as to prevent shorting of the emitter-base junction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-3 are cross-sectional views of an integrated circuit structure in successive stages of development in the fabrication of the molybdenum-aluminum interconnect system.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 depicts an integrated circuit fabricated within a body of semiconductor material 10, preferably N- silicon. The integrated circuit contains a shallow diffused NPN transistor 12 and a P- type resistor 14. The circuit may also include PNP type transistors, N type resistors and other semiconductor devices. The transistor 12 has an N+ type collector contact region 16 formed in the substrate 10, a P- type base region 18 formed in the substrate 10, and an N+ type emitter region 20 formed in the base region 18. The resistor 14 has a P- region 24 formed in the substrate 10. The total wafer is covered by a dielectric layer of isolating material 26, preferably silicon oxide. All of these regions are formed by conventional planar diffusion techniques.
Upon completion of the planar semiconductor devices, a conventional photoresist and oxide etch process is used to expose N+ type contact apertures in the silicon oxide layer 26, which for the devices shown in FIG. 1, are collector contact aperture 28 and emitter contact aperture 30. As is well known in this process, a photoresist layer is deposited on the oxide mask, the photoresist is exposed to light in accordance with a desired pattern, the pattern is developed through unexposed portions of the photoresist and the exposed portions of the oxide layer are removed with a suitable etchant. The remaining photoresist is then removed by stripping to leave an oxide mask with windows for the subsequent metal deposition.
The wafer is then cleaned and placed in a vacuum evaporation apparatus. In this apparatus, the molybdenum is first melted and then vaporized by a heated filament. A thin film of molybdenum metal of approximately 500-1000 angstroms is deposited on the wafer as shown in FIG. 1 as layer 32. Though using vacuum evaporation techniques, the molybdenum may be deposited by electronic beam vacuum evaporation or sputtering.
The metallized wafer is again coated with photoresist, exposed with a new mask to define the contact apertures for the P type regions, which for the devices shown in FIG. 2, are base contact aperture 34 and resistor contact apertures 36 and 38. The exposed photoresist is developed and a suitable etchant is used to remove the molybdenum above the P contact regions. Using the molybdenum as a mask, the dielectric 32 is removed by a suitable etchant to expose the planar surface of the P type contact regions. At this point, the molybdenum may be etched again to eliminate any molybdenum hangover of the P contact apertures 34, 36 and 38.
The remaining photoresist is then removed by stripping and the wafer is cleaned. A layer of aluminum of approximately 10,000 angstroms is deposited over the total wafer by vacuum evaporation, preferably, or any of the methods previously enumerated. A photoresist process is performed to define the interconnect patterns between the devices in the integrated circuit producing the structure as shown in FIG. 3. The N+ contact regions of collector 16 and emitter 20 have a combined molybdenum-aluminum metal contact formed of molybdenum layer 32 and aluminum layer 40. The base region 18 and the P- resistor have metal contacts formed from aluminum layer 40 only. The interconnect system of the present invention also provides a molybdenum layer between the aluminum layer and the dielectric insulator 32.
The final structure is primarily aluminum interconnect system wherein all emitter and other N+ contacts are made of molybdenum and aluminum and all P- base and resistor contacts are made of aluminum. This interconnect structure then satisfies both the requirements that the metal make a low resistive, non-rectifying contact with all types of silicon and that the metal must not react substantially with silicon at moderate temperatures.
The above processes may be modified so as to use only two photoresist processes instead of three to form the interconnect dual metal system of the present invention. To accomplish this, the emitter region and the collector contact region must be formed using a wash emitter process. This process involves the diffusion of the emitter and the collector contact region in an atmosphere such that only a small amount of oxide grows in these contact regions during diffusion. This small amount of oxide is removed by a non-selective oxide removal. Thus the additional photoresist and oxide etch to define the N+ contact regions and the eliminated andthe process of the present invention would include no extra steps over that used for conventional one-metal interconnect systems. The process then proceeds as previously described wherein the molybdenum is deposited, contact windows are etched through the molybdenum and the insulator to provide contact windows for the -contact areas, aluminum is deposited and the aluminum and molybdenum are delineated to define the interconnect pattern. | An integrated circuit having a metal interconnect system formed with molybdenum engaging all contact areas of N conductivity type regions and aluminum engaging said molybdenum and engaging all contact areas of P conductivity type regions. | 7 |
FIELD OF THE DISCLOSURE
[0001] The present disclosure is generally directed toward data storage and more particularly using a social media website.
BACKGROUND
[0002] Currently, social media data is stored in a highly-distributed data storage architecture (e.g., the “cloud”), which may include social media sites (Facebook, Twitter, YouTube, etc.). Access to all relevant social media data, even limited to customers or transactions with the customers, may not be possible or practical. A contact center wishing to maintain customer and customer transaction data, or a portion thereof, may replicate the data as needed in the contact center's data storage. While data storage requirements may make such data storage cumbersome and resource intensive, legal requirements may provide a strict prohibition on any attempt to gather and/or maintain certain data originating from social media websites.
[0003] The contact center may also have their own private customer data associated with a customer. When the contact center links to the social media site, such as to communicate with a customer via the social media site, the contact center may be unable to retrieve both sides of the transaction for storage and/or future use. Managing social media site interactions is difficult when the contact center is only able to control half of the data involved in a customer interaction. The contact center typically will find it difficult to match up the social presence of the customer with the customer's contact center presence. Furthermore, without a complete history available, determining what issue, transaction state, or context applies to this interaction can add to the difficulty. The result is delayed service, errors, or repeated questions to catch both sides up on the information from previous interaction(s). As a result, despite the advances in managing customer relationships utilizing social media sites, the ability to implement the advantages may be limited.
SUMMARY
[0004] It is with respect to the above issues and other problems that the embodiments presented herein were contemplated.
[0005] In addition to the technical issues associated with accessing and/or storing private data from social media websites, legal requirements often restrict the methods and types of data that may be gathered and/or maintained for a customer. For example, the European Union may mandate the separation of user provided data, such as that hosted on a social media site, and private customer data, such as that provided by a customer to an enterprise. An enterprise utilizing social media to interact with customers, which may include potential customers, prospects, persons expressing an interest (positive, negative, or neutral), etc., may be prevented from integrating social media data and private customer data. Accordingly, there is a need to link contact center data and social media data in a manner acceptable to the contact center, customer, and regulatory agencies.
[0006] As disclosed herein with respect to certain embodiments, encrypted data specific to a customer, transaction, etc. may be stored on a social media site that is used by the contact center when interacting with the customer. The data could be a customer ID, transaction, transaction state, preference(s), or other data that pertains to the customer-business relationship. The encryption algorithm may use some specific customer data during key generation to avoid duplication, theft, or spoofing attempts with the data.
[0007] In other embodiments, a tag or other identifier serves as a pointer to private data while the tag itself is maintained on the social media site. The tag or pointer may also be encrypted. As a benefit, a customer's social presence on a social media site can be readily associated with private data held by the contact center. The tag may be placed in a post, in a profile, coded in the response to the customer, or other non-contact center controlled area, could be managed in the use or encoding of fonts, sizes, styles, hidden fields, etc. The tag then associates the customer, via the social media site, to private data or a data store of the contact center.
[0008] Upon first contact and validation (by an automated and/or human agent) of the customer, an attempt is made to store a token, such as a customer identifier. The token may be encrypted such that the only intended user of the token is the contact center. Content, such as a post, entry in a profile, or other content-bearing aspect of the social media site is selected to host the token. The token may be visible to a casual observer or hidden from view (e.g., maintained as metadata on a social media site).
[0009] When contact is made with a previous customer, a search is done for the key in both the profile and transaction. If found, then the information may be loaded for reference by the agent. In addition, by saving and noting where tokens used as keys are stored across several sites, this method and context may be used to display customer information when the customer is engaged in a voice call, chat, email, or other non-social media site interaction.
[0010] As a benefit of certain embodiments, the problem of maintaining a rich user context related to social media, without hosting any social media data internally in the contact center, may be provided. This benefit may continue to increase in value as the privacy concerns over social media and monitoring continue to increase.
[0011] In a non-limiting example, a customer “likes” a company, causing the company to validate/match the customer account. Once matched, a token in the form of an encrypted value is stored on the social site for reference and is accessible upon a future interaction. For example, Sam engages in a chat over Twitter direct message regarding a flight delay. An encrypted value for Sam (customer/transactional) ID may be retrieved to start the transaction and an encrypted transaction ID may be created and stored as a part of the direct message chain. Sam's ID is attached to the data and the data trails help the contact center manage what has occurred on the premise side. By marking Sam's profile and his communication, linking his encryption key to Sam's customer data at the contact center and dumping his data to an agent, the agent Martha, an agent of the airline, can effectively help Sam with his flight concerns. Martha is assisted with the knowledge that Sam sent four additional Twitter direct messages in the last two months for flight delays. Martha helps Sam with an apologetic demeanor that might not have existed had she not been aware of the previous delays.
[0012] Certain embodiments may utilize private/public type keys for encryption/decryption of tokens. Other encryptions means may also be utilized. Additionally, the key may be portable, such that a token may be used across multiple social sites.
[0013] As a further benefit, a customer maintains much of their own data with respect to a contact center interactions. For example, if a customer were to purge their Twitter account or even if the purge was limited to all transactions related to a particular company, the company would be limited to their own private data. If legal or other practices require the contact center data to be deleted, the contact center may delete their own records and, if the customer chose to maintain their information related to the contact center on their social media account, it would be at the customer discretion and outside of the technical and/or legal authority of the contact center to maintain or delete such data.
[0014] The embodiments disclosed herein may generally, but not exclusively, fall into, at least, one of three parts:
[0015] 1. Customer token/key creation: Tokens may be encrypted with keys. Tokens and/or keys may be created with standard encryption techniques, subject to country or other locale requirements or restrictions, and performed on demand and stored in the Customer Relationship Management (“CRM”) customer record for reference when needed. The encrypted token may utilize various aspects of the customers social media profile ID, customer social media transition IDs, company CRM assigned ID, or other unique information linking the customer and/or the transaction.
[0016] 2. Storage of customer tokens inside customer social media: Profile tokens and transaction tokens are two possibilities modes for storage.
[0017] a. Profile token: When a customer performs an action to like, follow, attach, etc. based on the facilities of the social network, the customer is generally accepting/approving the company for some level of access or activity. The company is made aware of the new connection through either polling of information, or notification received from social media site. The company may then attempt to match, either automatically or manually, the social customer with an existing customer record. If no match is found, a new record is created and encrypted token created. If a match, encrypted token is accessed. The invention then inserts (e.g., stores) the token in the customer profile on the social media site for reference on a future contact.
[0018] The token may be stored in an existing field or a newly created field, depending on the attributes of the social media site. The field may be a public field or a private field depending on the site. The token is not stored in the company controlled data repositories.
[0019] b. Transaction token: During a post/comment or other form of messaging interaction (public or private) with a customer, an attempt is made to identify the customer (see, “profile token” above). A transaction token may be created for the specific transaction. The transaction token will be stored in one of the response interactions from the company.
[0020] Various methods may be used to minimize the visibility of the token, including storing at the end of a message, storing using html markup language to token hidden, storing on an attribute of the message, or other options that might be developed by social media sites in the future. The interaction token may be created with the CRM customer ID and transaction ID as part of the token and/or key. As above, the transaction token is stored in the social media site and not in company controlled data repositories.
[0021] 3. Retrieval and usage of token. When a new customer interaction, via a social media website, arrives (e.g., post, comment, or other messaging interaction), the invention will look to see if there is a token previously stored in the transaction and/or customer profile. If no token is found, the creation method, such as the one described above (see #2, above), is executed to create a token. If a token is found, the token is used then used to find the customer CRM record and/or any existing transactions, history, links, and pointers. Next, the transaction will be searched for a transaction token. If not found, one will be created and stored with the next reply. If found, a query for the transaction will be initiated to find the transaction in the CRM data using this token.
[0022] As a benefit, tracing of the social media history/data is enabled, without having any social media data stored internally to the company. The information is then made available to either the automated transaction processing and/or as a visual summary to the agent. Traditional contact center transactions (e.g., voice, video, email, chat) may benefit from the enhanced knowledge provided via the token to present information about the social media history of the customer linked through tokens. Implementation of certain features disclosed herein will be enabled based upon specific features and/or modes of operation provided by specific social media sites.
[0023] In one embodiment, a method is disclosed, comprising: generating a token that identifies a customer to a contact center; accessing a portion of the social media website associated with the customer; and causing the token to be stored on the portion of the social media website.
[0024] In another embodiment, another method is disclosed, comprising: receiving a work item from a customer of a contact center; in response to receiving the work item, attempting to locate a token stored on a social media website; upon locating the token, retrieving the token; processing the work item by a resource of the contact center; updating the token in accord with the work item; and causing the updated token to be stored on the portion of the social media website.
[0025] In yet another embodiment, a system is disclosed, comprising: a communication interface; a processor; and wherein the processor is operable to perform: generating a token that identifies a customer to a contact center; accessing, via the communication interface, a portion of the social media website associated with the customer; and causing the token to be stored on the portion of the social media website.
[0026] The terms “company” and “contact center” may be used synonymously or differently. A company, as used herein, generally refers to a business enterprise engaged in the sale or offering for sale of goods or services. A contact center is engaged in attending to the needs of the customers and/or potential customers, which may include selling and offering to sell the goods or services of the company. A contact center and a business may be the same business enterprise or different, such as when the contact center is a contractor, division, affiliated company, or otherwise acting on behalf of the company.
[0027] The phrases “at least one,” “one or more,” and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C,” “at least one of A, B, or C,” “one or more of A, B, and C,” “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together.
[0028] The term “a” or “an” entity refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising,” “including,” and “having” can be used interchangeably.
[0029] The term “automatic” and variations thereof, as used herein, refers to any process or operation done without material human input when the process or operation is performed. However, a process or operation can be automatic, even though performance of the process or operation uses material or immaterial human input, if the input is received before performance of the process or operation. Human input is deemed to be material if such input influences how the process or operation will be performed. Human input that consents to the performance of the process or operation is not deemed to be “material.”
[0030] The term “computer-readable medium” as used herein refers to any tangible storage that participates in providing instructions to a processor for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, NVRAM, or magnetic or optical disks. Volatile media includes dynamic memory, such as main memory. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, magneto-optical medium, a CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, a solid state medium like a memory card, any other memory chip or cartridge, or any other medium from which a computer can read. When the computer-readable media is configured as a database, it is to be understood that the database may be any type of database, such as relational, hierarchical, object-oriented, and/or the like. Accordingly, the disclosure is considered to include a tangible storage medium and prior art-recognized equivalents and successor media, in which the software implementations of the present disclosure are stored.
[0031] The terms “determine,” “calculate,” and “compute,” and variations thereof, as used herein, are used interchangeably and include any type of methodology, process, mathematical operation or technique.
[0032] The term “module” as used herein refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and software that is capable of performing the functionality associated with that element. Also, while the disclosure is described in terms of exemplary embodiments, it should be appreciated that other aspects of the disclosure can be separately claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] The present disclosure is described in conjunction with the appended figures:
[0034] FIG. 1 depicts a communications system in accordance with embodiments of the present disclosure;
[0035] FIG. 2 depicts another aspect of the communication system in accordance with embodiments of the present disclosure;
[0036] FIG. 3 depicts a number of illustrative means for storing contact center data on a social media website in accordance with embodiments of the present disclosure;
[0037] FIG. 4 depicts the storage of contact center data on a social media website in accordance with embodiments of the present disclosure;
[0038] FIG. 5 depicts the use of contact center data stored on a social media website in accordance with embodiments of the present disclosure;
[0039] FIG. 6 depicts a process for storing contact center data on a social media website in accordance with embodiments of the present disclosure;
[0040] FIG. 7 depicts a first process for using contact center data stored on a social media website in accordance with embodiments of the present disclosure.
[0041] FIG. 8 depicts a second process for using contact center data stored on a social media website in accordance with embodiments of the present disclosure.
DETAILED DESCRIPTION
[0042] The ensuing description provides embodiments only, and is not intended to limit the scope, applicability, or configuration of the claims. Rather, the ensuing description will provide those skilled in the art with an enabling description for implementing the embodiments. It being understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the appended claims.
[0043] The identification in the description of element numbers without a subelement identifier, when a subelement identifiers exist in the figures, when used in the plural, is intended to reference any two or more elements with a like element number. A similar usage in the singular, is intended to reference any one of the elements with the like element number. Any explicit usage to the contrary or further qualification shall take precedence.
[0044] The exemplary systems and methods of this disclosure will also be described in relation to analysis software, modules, and associated analysis hardware. However, to avoid unnecessarily obscuring the present disclosure, the following description omits well-known structures, components and devices that may be shown in block diagram form, and are well known, or are otherwise summarized.
[0045] For purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the present disclosure. It should be appreciated, however, that the present disclosure may be practiced in a variety of ways beyond the specific details set forth herein.
[0046] FIG. 1 shows an illustrative communication system 100 in accordance with at least some embodiments of the present disclosure. The communication system 100 may be a distributed system and, in some embodiments, comprises a communication network 104 connecting one or more communication devices 108 to a work assignment mechanism 116 , which may be owned and operated by an enterprise administering a contact center in which a plurality of resources 112 are distributed to handle incoming work items (in the form of contacts) from customer communication devices 108 .
[0047] In other embodiments, work items may be received or pulled from social media website 130 . Work items received via social media website may be posts, or similar comment, on a particular forum or company “page” and may further be received or pulled by work assignment mechanism 116 . Work items may be pulled as posts on non-company pages, such as an individual page, user group page, common interest page and the like. Posts having a particular keyword, phrase, user, or other aspect may be discovered by work assignment mechanism 116 and retrieved as work items. As social media website 130 takes various forms, also contemplated by the embodiments herein are the various forms of user provided posts and interacting with users. For example, a post may be a comment on a user's own page, a company page, video, image, another user's comment, the same user's comment, or other aspect operable to receive a comment from a user. More specifically, Likes, Tweets, media, comments, endorsements, shares, and other inputs from a user on a social media website 130 may similarly be posts and potentially also be work item and routed to resource 112 .
[0048] In accordance with at least some embodiments of the present disclosure, the communication network 104 may comprise any type of known communication medium or collection of communication media and may use any type of protocols to transport messages between endpoints. The communication network 104 may include wired and/or wireless communication technologies. The Internet is an example of the communication network 104 that constitutes an Internet Protocol (IP) network consisting of many computers, computing networks, and other communication devices located all over the world, which are connected through many telephone systems and other means. Other examples of the communication network 104 include, without limitation, a standard Plain Old Telephone System (POTS), an Integrated Services Digital Network (ISDN), the Public Switched Telephone Network (PSTN), a Local Area Network (LAN), a Wide Area Network (WAN), a Session Initiation Protocol (SIP) network, a Voice over IP (VoIP) network, a cellular network, and any other type of packet-switched or circuit-switched network known in the art. In addition, it can be appreciated that the communication network 104 need not be limited to any one network type, and instead may be comprised of a number of different networks and/or network types. As one example, embodiments of the present disclosure may be utilized to increase the efficiency of a grid-based contact center. Examples of a grid-based contact center are more fully described in U.S. patent application Ser. No. 12/469,523 to Steiner, the entire contents of which are hereby incorporated herein by reference. Moreover, the communication network 104 may comprise a number of different communication media such as coaxial cable, copper cable/wire, fiber-optic cable, antennas for transmitting/receiving wireless messages, and combinations thereof.
[0049] The communication devices 108 may correspond to customer communication devices. In accordance with at least some embodiments of the present disclosure, a customer may utilize their communication device 108 to initiate a work item, which is generally a request for a processing resource 112 . Illustrative work items include, but are not limited to, a contact directed toward and received at a contact center, a web page request directed toward and received at a server farm (e.g., collection of servers), a media request, an application request (e.g., a request for application resources location on a remote application server, such as a SIP application server), and the like. The work item may be in the form of a message or collection of messages transmitted over the communication network 104 . For example, the work item may be transmitted as a telephone call, a packet or collection of packets (e.g., IP packets transmitted over an IP network), an email message, an Instant Message, an SMS message, a fax, and combinations thereof. In some embodiments, the communication may not necessarily be directed at the work assignment mechanism 116 , but rather may be on some other server in the communication network 104 where it is harvested by the work assignment mechanism 116 , which generates a work item for the harvested communication. An example of such a harvested communication includes a social media communication that is harvested by the work assignment mechanism 116 from a social media network or server. Exemplary architectures for harvesting social media communications and generating work items based thereon are described in U.S. patent application Ser. Nos. 12/784,369, 12/706,942, and 12/707,277, filed Mar. 20, 1010, Feb. 17, 2010, and Feb. 17, 2010, respectively, each of which are hereby incorporated herein by reference in their entirety.
[0050] The format of the work item may depend upon the capabilities of the communication device 108 and the format of the communication. In particular, work items are logical representations within a contact center of work to be performed in connection with servicing a communication received at the contact center (and more specifically the work assignment mechanism 116 ). The communication may be received and maintained at the work assignment mechanism 116 , a switch or server connected to the work assignment mechanism 116 , or the like until a resource 112 is assigned to the work item representing that communication at which point the work assignment mechanism 116 passes the work item to a routing engine 132 to connect the communication device 108 which initiated the communication with the assigned resource 112 .
[0051] Although the routing engine 132 is depicted as being separate from the work assignment mechanism 116 , the routing engine 132 may be incorporated into the work assignment mechanism 116 or its functionality may be executed by the work assignment engine 120 .
[0052] In accordance with at least some embodiments of the present disclosure, the communication devices 108 may comprise any type of known communication equipment or collection of communication equipment. Examples of a suitable communication device 108 include, but are not limited to, a personal computer, laptop, Personal Digital Assistant (PDA), cellular phone, smart phone, telephone, or combinations thereof. In general each communication device 108 may be adapted to support video, audio, text, and/or data communications with other communication devices 108 as well as the processing resources 112 . The type of medium used by the communication device 108 to communicate with other communication devices 108 or processing resources 112 may depend upon the communication applications available on the communication device 108 .
[0053] In accordance with at least some embodiments of the present disclosure, the work item is sent toward a collection of processing resources 112 via the combined efforts of the work assignment mechanism 116 and routing engine 132 . The resources 112 can either be completely automated resources (e.g., Interactive Voice Response (IVR) units, processors, servers, or the like), human resources utilizing communication devices (e.g., human agents utilizing a computer, telephone, laptop, etc.), or any other resource known to be used in contact centers.
[0054] As discussed above, the work assignment mechanism 116 and resources 112 may be owned and operated by a common entity in a contact center format. In some embodiments, the work assignment mechanism 116 may be administered by multiple enterprises, each of which has their own dedicated resources 112 connected to the work assignment mechanism 116 .
[0055] FIG. 2 shows second illustrative embodiment 200 of a communication system 100 in accordance with at least some embodiments of the present disclosure. In one embodiment, contact center 202 maintains a first part 206 of customer data. Cloud 204 may be a public network (e.g., Internet) or other repository outside of the direct control of contact center 202 , including social media website 130 or a plurality thereof. Social media website 130 is then caused by contact center 202 to maintain a second part 208 of customer data.
[0056] In another embodiment, a customer maintains a presence on social media website 130 , which may include, but is not limited to, a profile, contact information, biographic information, interest, connections to other individuals, connections to groups, connections to corporate entities, comments, media, etc. In turn, the connections, relationships, and other interest may cause artifacts to be placed on social media website 130 that are explicitly or implicitly associated with the customer. For example, a content provider (e.g., individual, group, company, etc.) may cause certain items to be placed on a “wall” (e.g., a portion of the website associated with items of interest, news, etc.), such as when social media website 130 is Facebook, Pinterest, Twitter, etc. In another example, a content provider may explicitly place an item on social media website 130 to be associated with the customer, such as, “tagging” a photograph of the customer and/or sending a message and/or media file to the customer.
[0057] The presence of the second part 208 is at the discretion of the customer and/or the social media website. As a benefit, if the customer has a portion of social media website 130 , they may delete their presence and sever the relationship between themselves and social media website 130 . As a result, the preservation of any data within second part 208 is outside of the control of contact center 202 . If any data is maintained in second part 208 in a manner contrary to a legal requirement to remove it, the consequences would befall the party hosting the data, such as social media website 130 . In another example, if the customer had a connection to a business enterprise on social media website 130 and decided to purge only the relationship to the enterprise, any data maintained in second part 208 would be removed by the customer and/or social media website 130 and any failure to remove said data would be outside of the control of contact center 202 . The storage of data in second part 208 is variously embodied and discussed more completely with respect to FIG. 3 . However, if data was removed in first part 206 and, for example, the customer later had a reason to contact the business, certain information may be accessible from second part 208 .
[0058] FIG. 3 shows a number of illustrative embodiments whereby contact center 202 data may be stored on social media website 130 , in second part 208 . In one embodiment, token 300 is an unencrypted identifier of a particular customer. The contact center 202 (e.g., ABC Airlines itself or an affiliated organization), may receive a future communication or other work task and find post 302 having token 300 . As a result, social media website 130 stores the identifier.
[0059] In another embodiment, token 300 is encrypted. Encrypting token 300 may be beneficial to protect certain information from being revealed and/or misused. Token 300 may be embodied as a few characters (e.g., token 300 ) or many characters, digits, bits, etc. Token 300 may include just a few characters on up to nearly limitless number of characters, such as to incorporate a transaction, transaction history, customer details, or other information which may be selected as a matter of design choice.
[0060] The specific means by which token 300 is caused to be stored in second part 208 is variously embodied and may means by which visible, not-presented, and/or hidden information is provided to social media website 130 . In one embodiment, post 304 comprises presented portion 304 A and encoded portion 304 B. Encoded portion 304 B includes token 300 in a URL hidden, or at least not displayed, in presented portion 304 A. In yet another embodiment, post 306 comprises presented portion 306 A and encoded portion 306 B. Encoded portion 304 B includes token 300 in alternative text for an image. And, in yet another embodiment, token 300 may be placed in a field designated by social media website 130 , accessible by contact center 202 and may, or may not, be visible to one or more of the customer associated with token 300 , the public, or other entities. In other embodiments, token 300 may be stored with respect to fonts, styles, style sheets, or other metadata and/or hidden fields.
[0061] While token 300 may incorporate data associated with a customer and/or a transaction with the customer, token 300 may be a pointer to data stored outside of the social media website. In certain embodiments, the data may reside in customer records 118 or other data repository, including other social media websites.
[0062] FIG. 4 shows an illustrative embodiments whereby contact center 202 data may be stored on social media website 130 , in second part 208 . In one embodiment, customer 402 via customer communication device 108 , interacts with portion 404 of social media website 130 . Content within portion 404 is generally under the control of customer 402 , and to some degree the operators of social media website 130 , such as to place ads and select content. As well to support the removal of any content which may be in violation of the terms of use between customer 402 and social media website 130 . Portion 404 may be commonly referred to as the “page” for customer 402 . Portion 404 may include profile information as well as content provided, endorsed, or otherwise determined by customer 402 .
[0063] Customer 402 selected connection 408 associated with a business entity (e.g., ABC Airlines). Generally, such an endorsement is an agreement to allow some interaction between the endorser (customer 402 ) and the endorsee (e.g., ABC Airlines). Connection 408 may be an endorsement (e.g, “like,” “share,” etc.) or a more express desire to connect (e.g., “follow,” “friend”—as a verb, etc.) or other act whereby customer 402 agrees to the interaction with the endorsee.
[0064] In another embodiment, contact center 202 becomes aware of connection 408 by polling social media website 404 and/or receiving notifications from social media website 130 . Contact center 202 may attempt to identify customer 402 with respect to existing entries in customer records 118 or other data repository of customer data of contact center 202 . Processor 410 may then create new token 300 identifying customer 402 as a new customer or, if customer 402 is determined be an existing customer, token 300 may indicate the prior relationship. For example, a customer number or other indicia of the relationship may be used as token 300 . Additionally, token 300 may be encrypted.
[0065] Token 300 may be placed directly into portion 404 . Alternatively, response 414 is formatted by resource 112 incorporating token 300 . Other means of incorporating the token are discussed more fully with respect to FIG. 3 .
[0066] FIG. 5 shows an illustrative embodiments whereby contact center 202 , stored on social media website 130 , in second part 208 , may be used to process a work item. In one embodiment, customer 402 , via customer device 108 , causes a work item to be created. The work item may be created directly on portion 404 of social media website. For example, user 402 may create post 502 identifying an entity (e.g., ABC Airlines) monitored by contact center 202 and/or receiving notifications of posts from social media website 130 .
[0067] The work item is processed by contact center 202 , such as according to at least some of the embodiments discussed with respect to FIG. 1 . Processor 410 may access a prior response 414 to access token 300 therein to identify a prior transaction with customer 402 or to determine the identity of customer 402 with respect to one or more entries in customer records 118 . In another embodiment, processor 410 may cause profile page 506 to be accessed having a previously placed token 300 , such as embedded in the code for image 508 , a link, or other placement.
[0068] As a benefit, the identity of customer 402 , a transaction with customer 402 , or other artifact of the relationship between customer 402 and contact center 202 may be determined, without requiring access to customer records 118 . Resource 112 may then respond to the work item.
[0069] In one embodiment, processor 410 may then cause a reply post 504 to be posted. The context of post 504 may be determined, at least in part, on prior history with customer 402 and/or prior transactions with customer 402 within the realm of social media 130 and/or other communications mediums. Post 504 may further include an updated token, such as one embedded within image 510 .
[0070] With reference now to FIG. 6 , process 600 will be described in according with embodiments of the present disclosure. In one embodiment, processor 410 performs step 602 to access data identifying customer 402 . Step 602 may identify the customer 402 by a transaction or a combination thereof. For example, customer 402 may be identifying in step 602 as a specific individual who is known to contact center 202 , such as by having associated records in customer records 118 . In another example, customer 402 may be identified by a transaction, such as asking a question on social media website 130 or by contacting contact center 202 directly, such as via a telephone call, email, or other means. An example of a combination of individual and transaction identification includes, identification of a customer on one social media website 130 and a transaction on a second social media website 130 .
[0071] Step 604 then generates a token. The specific content of the token is a matter of design choice and may comprise a customer identifier, a transaction identifier, or other identifier. Optionally, step 606 may encrypt the token. Encryption may be performed using known means, such as private/public key encryption. Step 608 accesses a social media website and step 610 causes the token to be stored on the social media website in a manner known to the contact center. For example, as a hidden field of a HTML message, steganographic image, or a visible image, text, or link, or other means whereby the token may be preserved in the social media site.
[0072] With reference now to FIG. 7 , process 700 will be described in according with embodiments of the present disclosure. In one embodiment, step 702 receives a work item in contact center 130 . The work item may be presented to contact center 202 (e.g., the customer calls, emails, posts on social media website 130 , etc.). Alternatively, the work item may be received via polling or other searching for potential work items (e.g., comments on social media website 130 ). Step 704 searches for token 300 on social media website 130 .
[0073] In one embodiment, the work item is received via a particular social media website 130 and the same social media website 130 is searched in step 704 . Optionally, one or more additional social media websites 130 may be searched in step 704 , such as when token 300 is not located on a first social media website 130 . In another embodiment, the work item is not received via social media website 130 and step 704 searches one or more social media websites 130 for token 300 .
[0074] Step 706 determines if the token has been found. If yes, processing continues to step 708 . If not, processing continues to step 714 . Step 708 retrieves the token. Step 710 processes the work item, such as by one or more of resources 112 . Step 712 updates the token with respect to the work item. Step 716 then accesses the social media website and step 718 causes the updated token to be stored in the social media website. If step 706 determined to be false, step 714 generates the token. Optionally, step 714 and/or step 712 encrypts the token and/or step 710 decrypts the token.
[0075] With reference now to FIG. 8 , process 800 will be described in according with embodiments of the present disclosure. In one embodiment, step 802 receives a request to purge data. The request may be with respect to all data associated with a customer (e.g., a “forget me” request) or with respect to a particular transaction. Step 804 complies with the request received in step 802 . In certain embodiments, purging records in step 804 causes the records to be removed for all aspects of the enterprise, except for those records maintained as a matter of law and which may have access to such records restricted to compliance with requests from authorized regulatory agencies. For example, an enterprise receiving a “forget me” request may be required to purge all marketing data associated with the request but maintain certain financial records for a period of time, such as may be required to comply with tax recordkeeping regulations or other regulatory requirements.
[0076] Step 806 receives a work item associated with the customer and/or the transaction. For example, a customer may have decided to terminate the relationship with the enterprise and causes step 802 to request the customer's records be purged from the enterprise. Step 804 may have complied and purged all records or just the records related to the work item. At some period of time later, which could be almost instantly or many years later, the customer creates a work item in step 806 . For example, a customer may request step 802 purge their records with a particular enterprise, the enterprise complies in step 804 , and the customer realizes they had intended to have records purged from a different enterprise. Accordingly, the work item may be to recover all records or particular records and/or to reestablish the customer-enterprise relationship. In another example, a customer may have caused records to be purged in step 802 , which were complied with by step 804 . After some time, perhaps years later, the customer may create a work item in step 806 to reestablish the relationship with the enterprise (e.g., the enterprise changed a policy the customer found objectionable was rescinded, etc.) and/or recover a particular transaction (e.g., a receipt for a purchase made years ago to facilitate the customer's warranty claim).
[0077] Step 808 determines if the record exists. Executing step 808 may be necessary, such as when step 804 has not yet executed or not executed completely. For example, purge request 802 may have an associated grace period during which records may be retained. If step 806 receives the work item prior to the purging of the records, step 808 may determine the record exists and cause the work item to be processed by step 810 , such as by using the still-retained records.
[0078] Purge 804 may have removed, or otherwise cause to be inaccessible, the knowledge that a customer/transaction ever existed within the enterprise. In other embodiments, step 808 may be determined by a accessing a limited record indicating the records did exist at one time (e.g., “Customer #123—records purged”). In other embodiments the records may be entirely absent and a search is required. If the search does turn up the records (e.g., the work item was not associated with a customer/transaction who previously requested a purging of records), step 810 processes the request. If the records are not found or otherwise not available, processing continues to step 812 .
[0079] Step 812 searches one or more social media websites for the token and the token is retrieved. If encrypted, step 812 decrypts the token. The work item is then processed in step 816 . Step 818 may then update the token to reflect the work item. If such a request is also associated with a revocation of the purge request, the enterprise may being maintaining records as well.
[0080] In the foregoing description, for the purposes of illustration, methods were described in a particular order. It should be appreciated that in alternate embodiments, the methods may be performed in a different order than that described. It should also be appreciated that the methods described above may be performed by hardware components or may be embodied in sequences of machine-executable instructions, which may be used to cause a machine, such as a general-purpose or special-purpose processor (GPU or CPU) or logic circuits programmed with the instructions to perform the methods (FPGA). These machine-executable instructions may be stored on one or more machine readable mediums, such as CD-ROMs or other type of optical disks, floppy diskettes, ROMs, RAMs, EPROMs, EEPROMs, magnetic or optical cards, flash memory, or other types of machine-readable mediums suitable for storing electronic instructions. Alternatively, the methods may be performed by a combination of hardware and software.
[0081] Specific details were given in the description to provide a thorough understanding of the embodiments. However, it will be understood by one of ordinary skill in the art that the embodiments may be practiced without these specific details. For example, circuits may be shown in block diagrams in order not to obscure the embodiments in unnecessary detail. In other instances, well-known circuits, processes, algorithms, structures, and techniques may be shown without unnecessary detail in order to avoid obscuring the embodiments.
[0082] Also, it is noted that the embodiments were described as a process which is depicted as a flowchart, a flow diagram, a data flow diagram, a structure diagram, or a block diagram. Although a flowchart may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be re-arranged. A process is terminated when its operations are completed, but could have additional steps not included in the figure. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc. When a process corresponds to a function, its termination corresponds to a return of the function to the calling function or the main function.
[0083] Furthermore, embodiments may be implemented by hardware, software, firmware, middleware, microcode, hardware description languages, or any combination thereof. When implemented in software, firmware, middleware or microcode, the program code or code segments to perform the necessary tasks may be stored in a machine readable medium such as storage medium. A processor(s) may perform the necessary tasks. A code segment may represent a procedure, a function, a subprogram, a program, a routine, a subroutine, a module, a software package, a class, or any combination of instructions, data structures, or program statements. A code segment may be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, etc. may be passed, forwarded, or transmitted via any suitable means including memory sharing, message passing, token passing, network transmission, etc.
[0084] While illustrative embodiments of the disclosure have been described in detail herein, it is to be understood that the inventive concepts may be otherwise variously embodied and employed, and that the appended claims are intended to be construed to include such variations, except as limited by the prior art. | Contact centers receive work items for processing by resources, such as human or automated agents. Social media has become a popular medium to receive work items and communicate with customers. Legal concerns, such as those focused on customer privacy, may limit gathering and/or storing of certain customer data on resources controlled by the contact center or require the deletion of data collected from a revoked prior authorization. Storing at least some data, such as a token, within a customer's social media website allows a contact center to maintain connections, transactions, or other information related to a customer or a specific transaction with a customer as long as the customer and/or social media website chose not to delete the token. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 11/048,230 filed Feb. 1, 2005 now U.S. Pat. No. 8,163,317, which claims priority from U.S. application Ser. No. 10/001,136 filed Nov. 15, 2001, which claims priority from U.S. Provisional Application 60/256,902 filed Dec. 19, 2000 and United Kingdom Application 0028119.6 filed Nov. 17, 2000. U.S. application Ser. No. 11/048,230 filed Feb. 1, 2005 is also a continuation-in-part of International Patent Application No. PCT/IB2003/005278 filed Oct. 24, 2003 and published as WO 2004/039174 on May 13, 2004, which claims priority from United Kingdom Application 0225236.9 filed Oct. 30, 2002 and U.S. Provisional Application No. 60/438,852 filed Jan. 9, 2003. All of the above-mentioned applications, as well as all documents cited herein and documents referenced or cited in documents cited herein, are hereby incorporated herein in their entirety by reference.
FIELD OF THE INVENTION
The present invention relates to the control of the formation of acrylamide in a foodstuff.
BACKGROUND OF THE INVENTION
Acrylamide and polyacrylamide are used in industry for the production of plastics. It has been supposed that the main exposure for acrylamide in the general population has been through drinking water and tobacco smoking Exposure via drinking water is small and the EU has determined maximum levels of 0.1 microgram per liter water.
Acrylamide is water soluble and is quickly absorbed in the digestive tract. Excretion via the urine is fast and half of acrylamide is cleared from the body in a few hours.
The toxicological effects of acrylamide are well known. It causes DNA damage and at high doses neurological and reproductive effects have been observed. Glycidamide, a metabolite of acrylamide, binds to DNA and can cause genetic damage. Prolonged exposure has induced tumours in rats, but cancer in man has not been convincingly shown. The International Agency for Research on Cancer (IARC) has classified acrylamide as a “probably carcinogenic to humans” (Group 2A).
Acrylamide has been shown to induce gene mutations in cultured animal cells and also in animals treated in vivo. Thus it is assumed that exposure also to very low doses of acrylamide increases the risk for mutation and cancer.
High doses of acrylamide have been applied in the toxicological studies, which is an accepted practice. 25-50 mg per kg body weight is the lowest dose that has been shown to increase the mutation frequency in mouse. Recent studies in the laboratory of the Swedish Food Administration have shown that chromosome aberrations are induced in mice at 10-20 times lower doses.
Among the acrylamide metabolites glycidamide is considered the most likely candidate for causing genetic damage. Glycidamide has been found in mice and rats, and also in humans exposed to acrylamide.
Neurological damage was observed when rats were given acrylamide in their drinking water. The lowest effective dose was 2 mg/kg body weight and day, and the highest no-effect dose was 0.5 mg/kg body weight and day. Also humans exposed to high doses of acrylamide have shown neurological damage, e.g. some workers occupied in the building of the tunnel at Hallandsåsen. It is difficult to assess the highest acrylamide dose in humans that does not cause neurological effects (NOEL). The level is probably several times higher than the average acrylamide intake from food.
Decreased fertility was observed in rats exposed to 5-10 mg acrylamide/kg body weight and day.
Epidemiological studies in man have not shown a correlation between exposure to acrylamide and increased cancer rate. These studies have been criticised because the number of studied persons was too low considering the expected effect.
Two long-term studies in rats have shown a substantial increase of tumours in different organs when the animals were exposed to acrylamide in drinking water. Similar studies have been made in mice. The lowest effective dose was 2 mg/kg body weight per day.
In the studies with rats the increase of tumours was most evident in specific organs, e.g. mammary gland, uterus, adrenal gland, scrotal mesothelium. In mice there was an increase of lung and skin tumours. These cancer studies have been used for the assessment of the risk of cancer in humans due to acrylamide exposure.
It should be noted that the genotoxic studies have indicated that there is no threshold value for the risk of cancer induced by acrylamide, i.e. there is no dose of acrylamide so low that it does not increase the risk of cancer. In making these assessments it is assumed that man and rat have the same sensitivity for cancer induction by acrylamide.
The results of the risk assessments are somewhat different since they are based on different mathematical models. By consumption of 1 microgram acrylamide/kg body weight per day the lifetime risk for cancer has been calculated to
4.5 per 1000 (U.S. EPA) 0.7 per 1000 (WHO) 10 per 1000 (Granath et al. 1999, Stockholm University)
Recent analyses have now indicated that the exposure to acrylamide is probably considerably higher (for non-smokers) from consumption of certain foods that have been heated. As reported in J Agric Food Chem. 2002 Aug. 14; 50(17):4998-5006 a group at the University of Stockholm, headed by Prof. Margareta Tornqvist, has found that acrylamide is formed during heating of starch-rich foods to high temperatures.
The Swedish National Food Administration has developed a LC/MS/MS-method for the analysis of acrylamide in foods. Analysis has shown that acrylamide is present in a large number of foods, including many regarded as staple foods. The levels of acrylamide differ widely within each food group analysed.
Using information on the levels in different foods and Swedish food consumption data, it is suggested that a significant number of annual cancer cases can be attributed to acrylamide.
When foodstuffs were analysed at the Swedish National Food Administration (NFA) in Uppsala and at AnalyCen AB in Lidkoping it was found that some foodstuffs, which had been heated, could contain relatively high levels of the substance acrylamide. In total, more than 100 food samples have been analysed at the NFA. The food survey comprised bread, pasta, rice, fish, sausages, meat (beef and pork), biscuits, cookies, breakfast cereals and beer, etc as well as some ready-made dishes such as pizza and products based on potatoes, maize and flour.
The levels of acrylamide vary considerably between single foodstuffs within food groups, but potato crisps and French fries generally contained high levels compared to many other food groups. The average content in potato crisps is approximately 1000 microgram/kg and in French fries approximately 500 microgram/kg. Other food groups which may contain low as well as high levels of acrylamide are crisp bread, breakfast cereals, fried potato products, biscuits, cookies and snacks, e.g. popcorn.
Foodstuffs which are not fried, deep fried or oven-baked during production or preparation are not considered to contain any appreciable levels of acrylamide. No levels could be detected in any of the raw foodstuffs or foods cooked by boiling investigated so far (potato, rice, pasta, flour and bacon).
According to the NFA food survey “Riksmaten 1997-98”, which is based on approximately 1200 individuals between the age of 17 to 70 who recorded their food consumption during one week, an average intake of acrylamide of approximately 25 microgram per day (maximum intake is approximately six times higher) is obtained, based on the food groups shown below. The remaining food groups are estimated to account for approximately 10-15 microgram of acrylamide; in total an average intake of 35-40 microgram. The percentage contribution based on an intake of 40 microgram acrylamide per day results in:
potato products: 36% (French fries 16%, fried potatoes 10%, crisps 10%) bread: 16% biscuits, cookies and wafers: 5% breakfast cereals: 3% remaining foodstuffs groups, basically not investigated yet: 40%
Young adults (17 to 34 years of age) have, according to “Riksmaten”, a higher consumption of snacks (nuts, chips and popcorn) than other adults. For children under 17 years of age newer data are lacking In the food survey “Ungdom mot år 2000” (Samuelson et al 1996), which was carried out 1993-94 among 15-year olds in Uppsala and Trollhättan, the consumption of snacks was comparable to that of young adults in Riksmaten. Children have a lower average body weight than the 70 kg generally assumed when carrying out risk assessments. This implies that the food intake per kg body weight and the exposure to various substances could be even larger for those groups of individuals compared to adults. According to Riksmaten, 10 percent of the adult population consumes 90 percent of the snacks consumed in Sweden.
An alternative way of estimating the intake of acrylamide is by adduct measurement, that is to measure a reaction product of acrylamide with the protein of the blood, the haemoglobin (Tornqvist et al 1997). This reaction product seems to occur in all investigated humans at approximately the same levels and is furthermore a measurement of the continuously administered dose of acrylamide. The reason is unknown in this case, but workers who were exposed to acrylamide at the tunnel accident at Hallandsåsen in Sweden had higher levels of this reaction product in their blood.
In the general population, although not in smokers (who have a level of this adduct 2-3 times the background level), the background level has been estimated to account for a daily intake corresponding to approximately 100 microgram per day.
Other sources than foodstuffs (estimated average intake of 35-40 μg/day), e.g. cosmetics, drinking water, and a possible endogenous formation in the body of acrylamide, could, to a lower extent contribute to the background level. Estimated administered amount of acrylamide for the formation of the background level together with levels of acrylamide in foodstuffs are, however, presently extremely uncertain.
A Report from Swedish Scientific Expert Committee entitled “Acrylamide In Food-Mechanisms of formation and influencing factors during heating of foods” discloses possible mechanisms for the formation of acrylamide in food. Relevant extracts from this report are given below in Appendix 1.
According to Health Canada, model experiments carried out in the Food Directorate showed that when asparagine is heated with glucose, acrylamide is produced. In an open letter, Health Canada stated “The production of acrylamide in these studies was temperature dependent and gave comparable results to those found when potato slices were similarly heated. At this time, not much is known about other possible pathways of formation of acrylamide in foods.”
Further discussion of reactions occurring during heating of food is given in Principles of Food Chemistry pages 100-109. This discussion is provided in Appendix 2.
The present invention alleviates the problems of the prior art.
Some aspects of the invention are defined in the appended claims.
BRIEF SUMMARY OF THE INVENTION
In one aspect the present invention provides a process for the prevention and/or reduction of acrylamide formation and/or acrylamide precursor formation in a foodstuff containing (i) a protein, a peptide or an amino acid and (ii) a reducing sugar, the process comprising contacting the foodstuff with an enzyme capable of oxidising a reducing group of the sugar.
In one aspect the present invention provides use of an enzyme for the prevention and/or reduction of acrylamide formation and/or acrylamide precursor formation in a foodstuff containing (i) a protein, a peptide or an amino acid and (ii) a reducing sugar, wherein the enzyme is capable of oxidising a reducing group of the sugar.
Acrylamide formation and/or acrylamide precursor formation in cooked foodstuffs, in particular starch foodstuffs and foodstuffs containing a protein/amino acid/peptide and reducing sugar is described in Appendices 1 and 2, for example by the Amadori reaction, and is known in the art. In such foodstuffs a sugar such as glucose, galactose and/or maltose may react with an amino acid such as asparagine, glutamic acid, lysine, or arginine. Any primary amine capable of nucleophilic attack on the carbonyl group of a reducing sugar may be involved This reaction may be an important step in the formation of acrylamide.
The present invention prevents and/or reduces the problematic condensation reactions between amino acids, in particular the amino group thereof, and reducing sugars which result in acrylamide or acrylamide precursor formation. These reactions may comprise the Amadori reaction, Heynes rearrangements, or reaction cascades resulting from the Maillard reaction. The present invention may prevent and/or reduce the reaction which directly results in acrylamide formation. It may also prevent and/or reduce reaction(s) which provide materials which further react to provide acrylamide, namely acrylamide precursors. Acrylamide precursors are often provided by degradation of carbohydrates. A typical acrylamide precursor is 2-propenal.
The problems of the formation of acrylamide and/or acrylamide precursor formation in foodstuffs containing a protein and a reducing sugar such as baked food products, in particular formation caused either completely or in part by the Amadori reaction, can be controlled by contacting the foodstuff with an enzyme capable of oxidising the reducing group of the sugar. This is a novel approach in which reducing sugar is oxidised to avoid acrylamide formation and/or acrylamide precursor formation by bringing the foodstuff into contact with an enzyme which is capable of performing the necessary oxidation and thereby eliminating the reducing sugar from the foodstuff by conversion.
In the present specification, by the term “prevention and/or reduction of acrylamide formation” it is meant that the amount of acrylamide produced is reduced and/or the period of time required for formation of a given amount of acrylamide is increased.
In some aspects preferably the process prevents and/or reduces Amadori reaction in a foodstuff.
Thus in one aspect the present invention provides a process for the prevention and/or reduction of Amadori reaction in a foodstuff containing (i) a protein, a peptide or an amino acid and (ii) a reducing sugar, the process comprising contacting the foodstuff with an enzyme capable of oxidising a reducing group of the sugar.
In one further aspect the present invention provides use of an enzyme for the prevention and/or reduction of Amadori reaction in a foodstuff containing (i) a protein, a peptide or an amino acid and (ii) a reducing sugar, wherein the enzyme is capable of oxidising a reducing group of the sugar.
In the present specification, by the term “prevention and/or reduction of Amadori reaction” it is meant that the extent of a Amadori reaction is reduced and/or the period of time required for completion of a Amadori reaction is increased.
In some aspects preferably the enzyme is capable of oxidising the reducing group of a monosaccharide and the reducing group of a disaccharide.
In some aspects preferably the enzyme is hexose oxidase (EC1.1.3.5) or glucose oxidase (EC 1.1.3.4). In a highly preferred aspect the enzyme is hexose oxidase. Preferably the HOX is obtained or prepared in accordance with WO 96/40935. Preferably the HOX is DairyHOX™ available from Danisco A/S, Denmark.
In some aspects preferably the enzyme may oxidise matlodextrins and/or celludextrins. In a preferred aspect the enzyme is a carbohydrate oxidase which may oxidise matlodextrins and/or celludextrins. Preferably the carbohydrate oxidase is obtained or prepared in accordance with WO 99/31990.
Hexose oxidase (HOX) is a carbohydrate oxidase originally obtained from the red alga Chondrus crispus . As discussed in WO 96/39851 HOX catalyses the reaction between oxygen and carbohydrates such as glucose, galactose, lactose and maltose. Compared with other oxidative enzymes such as glucose oxidase, hexose oxidase not only catalyse the oxidation of monosaccharides but also disaccharides are oxidised. (Biochemica et Biophysica Acta 309 (1973), 11-22).
The reaction of glucose with Hexose Oxidase is
D-glucose+H 2 O 2 +O 2 →δ-gluconolactone+H 2 O 2
In an aqueous environment the gluconolactone is subsequently hydrolysed to form gluconic acid.
As shown, HOX oxidises the carbohydrate at the reducing end at carbon 1 and thus eliminates the possible involvement of the carbohydrate in acrylamide formation and/or acrylamide precursor formation by Amadori rearrangement or later reaction with a ketoseamine or aldoseamine to a diketoseamine or a diaminosugar respectively.
In a preferred aspect of the present invention the enzyme is capable of oxidising the sugar of the foodstuff at the 1 position. This aspect is advantageous because it ensures that the reducing sugar is oxidised such that the reducing part of the sugar is no longer available to undergo a condensation reaction with an amino acid such the Amadori reaction.
In some aspects preferably the reducing sugar is selected from lactose, galactose, glucose, xylose, mannose, cellobiose and maltose.
In some aspects the reducing sugar is lactose or galactose.
In some aspects the reducing sugar is galactose.
In some aspects preferably the foodstuff is selected from bakery goods including bread and cakes, pasta, rice, fish, sausages, meat including beef and pork, biscuits, cookies, crisp bread, cereals, pizza, beverages including coffee, and products based on potatoes, maize and flour, including potato flour and potato starch products.
In some aspects the foodstuff is a beverage.
In some aspects the foodstuff is a starch containing foodstuff.
In some aspects the foodstuff is a cereal or part of a cereal.
In some aspects preferably the foodstuff is selected from a dairy foodstuff; milk based or milk containing foodstuff, such as gratin; an egg based foodstuff; an egg containing foodstuff; bakery foodstuffs including toasts, bread, cakes; and shallow or deep fried foodstuff such as spring rolls.
When the foodstuff is a dairy foodstuff it may be cheese, such as mozzarella cheese.
In some aspects preferably the foodstuff is a potato or a part of a potato. Typical potato products in which the present invention may be applied are French fries, potato chips (crisps), coated French fries and coated potato chips, for example French fries or potato chips coated with corn starch, and potato flour and potato starch products.
The enzyme may be contacted with foodstuff during its preparation or it may be contacted with the foodstuff after the foodstuff has been prepared yet before the food stuff is subjected to conditions which may result in the undesirable acrylamide formation and/or acrylamide precursor formation. In the former aspect the enzyme will be incorporated in the foodstuff. In the later aspect the enzyme will be present on the surface of the foodstuff. When present on the surface acrylamide formation and/or acrylamide precursor formation is still prevented as it is the surface of a material exposed to drying and atmospheric oxygen which undergoes the predominant acrylamide formation and/or acrylamide precursor formation.
When contacted with foodstuff during its preparation the enzyme may be contacted at any suitable stage during its production. In the aspect that the foodstuff is a dairy product it may be contacted with the milk during acidification of the milk and precipitation of the milk curd. In this process the enzyme (such as HOX) is not active during the anaerobic conditions created during the acidification and milk protein precipitation, but will be active in the dairy product such as cheese when aerobic conditions are created. Once in aerobic conditions the enzyme oxidise the reducing sugar and reduce the tendency to acrylamide formation and/or acrylamide precursor formation.
For application of the enzyme to the surface of the foodstuff, one may apply the enzyme in any suitable manner.
Typically the enzyme is provided in a solution or dispersion and sprayed on the foodstuff. The solution/dispersion may comprise the enzyme in an amount of 1-50 units enzyme/ml, such as 1-50 units Hexose Oxidase/ml.
The enzyme may also be added in dry or powder form. When in wet or dry form the enzyme may be combined with other components for contact with the foodstuff. For example when the enzyme is in dry form it may be combined with an anticaking agent.
It will be appreciated by one skilled in the art that in the practice of the present invention one contacts the foodstuff with a sufficient amount of enzyme to prevent and/or reduce a acrylamide formation and/or acrylamide precursor formation. Typical amounts of enzyme which may be contacted with the foodstuff are from 0.05 to 50 U/g (units of enzyme per gram of foodstuff), from 0.05 to 10 U/g, from 0.05 to 5 U/g, from 0.05 to 3 U/g, from 0.05 to 2 U/g, from 0.1 to 2 U/g, from 0.1 to 1.5 U/g, and from 0.5 to 1.5 U/g.
In one preferred aspect the use/process of the present invention further comprises use of a catalase or contacting a catalase with a foodstuff to remove oxygen and thereby prevent and/or reduce acrylamide formation and/or acrylamide precursor formation (such as 2-propenal formation).
In some aspects the foodstuff contains an amino acid. In some aspects the amino acid is asparagine. It has been identified that asparagine is particularly important in the formation of acrylamide in foodstuffs.
In a preferred aspect the enzyme prevents and/or inhibits Amadori reactions and subsequent reactions with asparagine resulting in the formation of acrylamide.
In some aspects the foodstuff contains a protein. In some aspects the foodstuff contains a peptide.
Acrylamide formation and/or acrylamide precursor formation in a foodstuff may take place during the heating thereof or may take place during storage of the foodstuff. For example acrylamide formation and/or acrylamide precursor formation can happen upon storage of any kind of seeds without heating. The enzyme of the present invention, such as HOX, may still be useful however in removing a second mole of aldose or ketose sugar which may react with the already formed Amadori product to yield the diketoseamine or diaminosugar.
Moreover the system of the present invention may prevent loss of the nutritionally important Lysine in foods.
As a further addition it may be noted that reducing sugars may play an important role in the initiation of Amadori and Maillard reactions at certain moisture levels of the foodstuff (8-12%), but that lipid auto-oxidation, which is also known to initiate Amadori reactions, becomes increasingly common at low moisture levels (6%) (McDonald 1999). Lipid oxidation may actually be the primary cause for the initiation of Amadori or Maillard reactions when reducing sugars are absent. The present enzyme, such as HOX, may serve the dual purpose of removing both reducing sugars and oxygen and thereby preventing lipid oxidation as well as sugar hydrolysis at all moisture levels.
The present invention will now be described in further detail by way of example only with reference to the accompanying figures in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 . Results from the use of hexose oxidase and glucose oxidase to reduce the amount of acrylamide developed by frying potato chips.
FIGS. 2 and 3 . Results from the use of hexose oxidase and glucose oxidase to reduce the amount of acrylamide developed by baking potato chips.
FIG. 4 . Statistical analysis of the results in FIG. 2 .
FIG. 5 . SRM Chromatograms of an extract of a fried potato spiked with 1000 ng/15 ml [ 13 C 3 ]acrylamide (internal standard). The transitions monitored are m/z 72>m/z 55 (upper, acrylamide) and m/z 75>m/z 58 (lower, [ 13 C 3 ]acrylamide).
FIG. 6 . Pathways of formation of key flavour intermediates and products in the Maillard reaction.
FIG. 7 . Loss of lysine occurring as a result of heating of several foods.
FIG. 8 . Reaction pattern of the formation of melanoidins from aldose sugars and amino compounds.
FIG. 9 . Reversible formation of glycosylamines in the browning reaction.
FIG. 10 . Amadori rearrangement.
FIG. 11 . Structure of 1-deoxy-1-glycin-β-D-fructose.
FIG. 12 . Heyns rearrangement.
FIG. 13 . 1,2-enolization mechanism of the browning reaction.
FIG. 14 . Proposed browning reaction mechanism according to Burton and McWeeney.
FIG. 15 . Effect of temperature on the reaction rate of D-glucose with DL-leucine.
FIG. 16 . Effect of pH on the reaction rate of D-glucose with DL-leucine
FIG. 17 . Decomposition of cysteine by a lipid free radical.
DETAILED DESCRIPTION OF THE INVENTION
Examples
Acrylamide content of foodstuffs may be determined in accordance with J Agric Food Chem. 2002 Aug. 14; 50(17):4998-5006.
Example 1
Pizza with Mozzarella Cheese
20 g mozzarella cheese (Karoline's Dansk mozzarella, 25% protein, 1% carbohydrate and 21% fat) is scaled in a beaker. 1 ml Hexose Oxidase solution (7.5 HOX units/ml) is sprayed onto the cheese. As a control 1 ml water is sprayed onto another sample of mozzarella cheese. The cheese is stored for 2 hours at room temperature. A dough is made from flour, salt and water. 10 g dough is scaled and placed in a petri dish. 5 grams of mozzarella cheese is placed on top of the dough and baked at 225° C. for 7 min. Another sample is baked for 15 min. After baking the samples are evaluated.
The samples in accordance with the present invention have a lower content of acrylamide than the control samples.
Example 2
The effect of hexose oxidase is tested in a gratin made by the following procedure.
75 g shortening (mp. 35° C.) and 100 g flour are heated in a pot during mixing. 350 ml skim milk (preheated to 90° C.) is added during continued mixing. Salt and pepper is added. 4 eggs are divided into yolk and egg white. The egg yolks are added individually. The egg white is whipped to a foam with 10 gram baking powder and mixed carefully into the dough. The dough is placed in 2 aluminium trays. One of the trays is sprayed with a solution of hexose oxidase 7.5 Units/ml and kept at room temperature for 30 minutes. The gratin is then baked in a air circulating oven at 175° C. for 20 minutes. After baking the gratin is evaluated.
The samples in accordance with the present invention have a lower content of acrylamide than the control samples.
Example 3
The consumption of fried potato as French fries (pommes frites) and potato chips (crisps) has increased significantly during the past two decades. One of the important parameters in the production of fried potatoes is level of reducing sugar. The level should remain low, because high level of reducing sugar contribute to higher levels of acrylamide.
In order to prevent an increase in the level of reducing sugar in potatoes during storage potatoes are often sprayed with a herbicide called chlorpropham, which prevents the potato from sprouting. Sprouting induces amylases in the potato which in turn form reducing sugars.
In this study one investigated if it is possible to reduce levels of acrylamide in fried potatoes by adding HOX to sliced potatoes before frying.
Procedure
Organic grown potatoes are used in order to ensure that no herbicides has been used. The potatoes are peeled and sliced into 2 mm thick slices using a food processor. Half of the slices are immersed in a water solution of HOX containing 100 Units/ml for 3 minutes. The other half of the potato slices are immersed in water for 3 minutes. The slices are then stored in a closed container for over night (16 hours) and then fried in vegetable oil for 2 minutes at 180° C.
Results
The samples in accordance with the present invention have a lower content of acrylamide than the control samples.
Example 4
Crisp Bread with Rye Flour
125 g rye flour
125 g flour
0.5 tsp baking powder
3 tsp sugar
2 tsp salt
100 g margarine
1.25 dl milk
1 egg
Procedure
Mix dry ingredients Crumble margarine into mixture, and quickly knead the dough with water and whisked egg Leave the dough to rest for 20 minutes, then roll it out on the plate, prick and cut it into 8×20 cm big loaves Bake for 10 minutes at 190° C. until light brown Break gently into pieces.
Results
The samples in accordance with the present invention have a lower content of acrylamide than the control samples.
Example 5
Determination of Glucose Oxidase and Hexose Oxidase Activity
Definition: 1 glucose oxidase (GOX) unit corresponds to the amount of enzyme which under the specified conditions results in the conversion of 1 μmole glucose per minute, with resultant generation of 1 μmole of hydrogen peroxide (H 2 O 2 ).
Definition: 1 hexose oxidase (HOX) unit corresponds to the amount of enzyme which under the specified conditions results in the conversion of 1 μmole of glucose per minute, with resultant generation of 1 μmole of hydrogen peroxide (H 2 O 2 ).
Assay of GOX and HOX activity in microtiter plates (300 μl).
The commonly used horse radish peroxidase dye substrate ABTS was incorporated into an assay, measuring the production of H 2 O 2 produced by HOX or GOX respectively. ABTS serves as a chromogenic substrate for peroxidase. Peroxidase in combination with H 2 O 2 facilitates the electron transport from the chromogenic dye, which is oxidised to an intensely green/blue compound.
An assay mixture contained 266 μl β-D-glucose (Sigma P-5504, 0.055 M in 0.1 M sodium phosphate buffer, pH 6.3), 11.6 μl 2,2′-Azino-bis(3-ethylbenzothiozoline-6-Sulfonic acid)(ABTS)(Sigma A-9941, 5 mg/ml aqueous solution), 11.6 μl peroxidase (POD)(Sigma P-6782, 0.1 mg/ml in 0.1 M sodium phosphate buffer, pH 6.3) and 10 μl enzyme (HOX or GOX) aqueous solution.
The incubation was started by the addition of glucose at 25° C. The absorbance was monitored at 405 nm in an ELISA reader. A standard curve, based on varying concentrations of H 2 O 2 , was used for calculation of enzyme activity according to the definition above.
The reaction can be described in the following manner:
β-D-glucose+O 2 +2H 2 O→gluconic acid+2H 2 O 2 (1)
H 2 O 2 +2ABTS (colorless)+2H + →2H 2 O+2ABTS (blue/green) (2)
Reaction (1) is catalysed by enzyme (HOX or GOX) Reaction (2) is catalysed by enzyme (POD)
Example 6
Use of Hexose Oxidase and Glucose Oxidase to Reduce the Amount of Acrylamide Developed by Frying Potato Chips
Frying
Italian potatoes of the sort Nicola, were peeled and sliced into pieces of approximately (3 mm×30 mm×40 mm). Portions of approx. 30 g of sliced potatoes were treated with 40 mL of one of the incubation solutions as described below. During treatment it was made sure that all potatoes were covered with solution and the incubating beakers were stirred at RT for 4 hours in total.
After the enzyme treatment the potato slices where air dried for app. 30 min and fried for 2.5 min in pure rapeseed oil (175° C.). Subsequently the potatoes were spread on tissue paper and allowed to cool for approx. 30 min. They were stored dark in closed containers at −20° C. They were then purified and analysed as described in example 7.2.
Treatment:
(0) 40 mL of demineralised water (=control) (1) 40 mL demineralised water containing 5 U/mL glucose oxidase (GOX, Sigma G-6125) (2) 40 mL demineralised water containing 5 U/mL hexose oxidase (HOX)
The results of the experiment are summarized in FIG. 1 .
It is evident from FIG. 1 that incubation prior to frying, using an incubation solution containing either GOX or HOX, had an effect on the relative level of acrylamide found in the fried potato. The largest effect was observed using HOX (˜65% reduction) (see treatment 2). A smaller effect was observed using the same dosage of GOX (˜41% reduction)(see treatment 1).
Example 7
Use of Hexose Oxidase and Glucose Oxidase to Reduce the Amount of Acrylamide Developed by Baking Potato Chips
7.1. Baking
Italian potatoes of the sort Nicola, were peeled and sliced as described in Example 6.
Portions of app 50 g were treated with 100 mL of incubation solution and incubated for 15 min, while stirring at RT. During treatment it was made sure that all potatoes were covered with solution.
After the enzyme treatment the potato slices where air dried for approx. 30 min and baked in a pre-heated oven for 30 min at 175° C. To account for differences in heating conditions of the oven, the baking plate was divided into 9 segments of equal size. Potatoes treated as in (1)-(3) (see below), were divided into 9 equal fractions and 1 fraction from each was placed in each segment to a total of 3 fractions per segment. This was done to minimize the chance of faulty results as a consequence of uneven heating in the oven. Subsequently the potatoes were spread on tissue paper and allowed to cool for approx. 30 min. They were stored dark in closed containers at −20° C.
Treatment:
(1) No incubation
(2) 100 mL demineralised water
(3) 100 mL demineralised water containing 50 U/mL hexose oxidase (HOX)
The results of the experiment are summarized in FIG. 2 and FIG. 3 .
Through statistical analysis of the results in FIG. 2 , it was found that HOX treated samples show significantly lower content of acrylamide compared to water treated samples.
TABLE 1
Table of Least Squares Means for Amount with 95.0 Percent
Confidence Intervals
Level
Count
Mean
Stnd. Error
Lower Limit
Upper Limt
GRAND
12
3147.75
MEAN
F1
Blank
4
3148.0
272.466
2531.64
3764.36
HOX
4
2501.5
272.466
1885.14
3117.86
Water
4
3793.75
272.466
3177.39
4410.11
See FIG. 4
TABLE 2 Multiple Range Tests for Amount by F1 Method: 95.0 percent LSD Homogeneous F1 Count LS Mean LS Sigma Groups HOX 4 2501.5 272.466 X Blank 4 3148.0 272.466 XX Water 4 3793.75 272.466 X Contrast Difference +/− Limits Blank − HOX 646.5 871.668 Blank − Water −645.75 871.668 HOX − Water *−1292.25 871.668 *denotes a statistically significant difference
7.2 Sample Preparation and Quantification by LC-MS/MS
Experimental
Materials
Methanol (Lab Scan, Dublin, Ireland), acetic acid, reagent grade ACS from Scharlau Chemie S. A. (Barcelona Spain).
Oasis MAX (6 cc, 150 mg, Part No. 186000370), Oasis MCX (6 cc, 150 mg, Part No. 186000256) from Waters (Milford, Mass., USA).
Acrylamide-1,2,3- 13 C 3 , 1 mg/ml methanol (Product nr. CLM-813-1.2) from Cambridge Isotope Laboratories, Inc. (MA, USA). Acrylamide (Product nr. 14857-1) from Aldrich, (Germany).
Instrumentals
The HPLC system consisted of a quaternary pump (G1311A), autosampler (G1313A), column compartment (G1316A) all from Agilent Technologies (Waldbronn, Germany).
An LCQ Deca Ion Trap mass spectrometer from Thermo Finnigan (San Jose, Calif., USA).
Column (Atlantis™ dC 18 3 μm, 2.1 mm id.*150 mm) from Waters (Milford, Mass., USA).
Chromatographic and MS Conditions
Mobile Phase
H 2 O/MeOH/AcOH (1000/5/1 by volume)
The flow rate was 0.20 ml/min.
MS Detector Settings
Capillary Temp (C): 275
Sheath Gas Flow: 96
Aux Gas Flow: 3
Source Type: ESI
Positive Mode
Source Voltage (kV): 2.00
MSn Micro Scans: 2
MSn Max Ion Time (ms): 500
Scan Event Details:
1: Pos (71.9) > (40.0-80.0) MS/MS: Amp. 34.0% Q 0.450 Time 30.0 IsoWidth 1.0 2: Pos (74.9) > (40.0-80.0) MS/MS: Amp. 34.0% Q 0.450 Time 30.0 IsoWidth 1.0
Standard and Sample Preparation
Calibration standards (acrylamide) were prepared with the following concentrations: 500, 150, 50, 15, 5 ng/ml in water. The concentration of internal standard (acrylamide-1,2,3- 13 C 3 ) was maintained at 40 ng/ml.
The sample to be analysed was coarsely ground with a knife. An aliquot (1 g) was homogenized (Ultra-Turrax T25) with 15 ml of internal standard, (ISTD, 1000 ng acrylamide 1,2,3- 13 C 3 /15 ml H 2 O) in a 100 ml beaker.
The homogenate was transferred to a 50 ml centrifuge tube and 2 ml of dichloromethane were added. The mixture was shaken and centrifuged at 18000 rev/min (=25000 RCF) in a Sorvall RC-5B centrifuge for 20 min. at 4° C.
An Oasis MAX cartridge and an Oasis MCX cartridge were each conditioned with 5 ml methanol followed by 2*5 ml water. After conditioning, they were combined in series with Oasis MAX on top.
An aliquot (1.5 ml) of the supernatant (water) was passed through the Oasis MAX/Oasis MCX tandem (fraction 1).
Water (5 ml) was added to the Oasis MAX/Oasis MCX tandem and the eluent was collected in three fractions: Fraction 2 (1 ml), fraction 3 (2 ml) and fraction 4 (2 ml). Fraction 3 was filtered through a 0.45-μm filter (13 mm GHP 0.45 μm Minispike, Waters) and subjected to analysis.
Appendix 1 and Appendix 2 follow.
APPENDIX 1
Chemical Mechanisms for Acrylamide Formation
Food science and technology have had interest in acrylamide itself (and/or its derivatives incl. polymers), and its applications and possible toxic effects for many years. For example, there are many reports on can coatings and food packaging, on food additives (preservatives, artificial sweeteners etc.) and on acrylamide polymers of suitable quality with low residual acrylamide monomer levels that are used in, e.g. the U.S. for treatment of poultry, potato, corn, and other wastes, with the resulting concentrated solids used as components of blended animal feeds (14-19).
There are only a few earlier reports on the occurrence of acrylamide in foods. For example, acrylamide has been reported to be present in plant material (potatoes, carrots, radish, lettuce, Chinese cabbage, parsley, onions, spinach, and rice paddy) (20). In 1 g plant samples, 1.5.100 ng acrylamide could be detected. Acrylamide was also reported to occur in sugar (21). The origin of the detected acrylamide in these foods is not known. It might be exogenous.
To the best of our knowledge, no proposed or proven reaction routes for the formation of acrylamide during food processing have been published. Therefore, what are described below are the hypotheses we find most relevant and probable in a food processing situation.
A. Acrolein (2-propenal, CH2=CH—CHO) is a three carbon aldehyde and thus reminds the structure of acrylamide (CH2=CH—C(O)—NH2). Further, acrolein is known to be formed by: 1. transformation of lipids 2. degradation of amino acids and proteins 3. degradation of carbohydrates 4. the Maillard reaction between amino acids or proteins and carbohydrates
Therefore, acrolein is a very probable precursor of acrylamide. Simple, fundamental chemical transformations (such as reaction with ammonia liberated from amino acids) can then convert acrolein (or a derivative from it) into acrylamide. The production of acrylamide through the reaction of acrolein with ammonia has been demonstrated in model systems (22).
B. Alternative formation mechanisms of acrylamide do not necessarily involve acrolein. For example, proteins and/or amino acids can after a series of transformations, such as hydrolyses, rearrangements, decarboxylations etc., eventually lead to acrylamide.
The processes mentioned above (A and B) are complicated and involve multistage reaction mechanisms which might also include free radical reactions to acrolein or acrylamide (23-25).
Acrolein Formation from Lipids
When oil is heated at temperatures above the smoke point, glycerol is degraded to acrolein, the unpleasant acrid black and irritating smoke (26-29). The formation of acrolein is known to increase with the increase in unsaturation in the oil and to lead to a lowering of the smoke point. The smoke point is higher for oils with higher content of saturated fatty acids and lower content of polyunsaturated acids. The smoke points for some of the main oils and fats are as follows: palm 240° C., peanut 220° C., olive: 210° C., lard and copra 180° C., sunflower and soybean 170° C., corn 160° C., margarine 150° C., and butter 110° C. Usually the smoke starts to appear on the surface of heated oils before their temperature reaches 175° C. The oil is first hydrolyzed into glycerol and fatty acids and then acrolein is produced by the elimination of water from glycerol by a heterolytic acid-catalyzed carbonium ion mechanism followed by oxidation (30).
Besides the above-mentioned mechanism for the formation of acrolein from acylglycerols, acrolein can also be produced as a result of oxidation of polyunsaturated fatty acids and their degradation products (31-34). A number of aldehydic products (including malondialdehyde, C3-C10 straight chain aldehydes, and α,β-unsaturated aldehydes, such as 4-hydroxynonenal and acrolein) are known to form as secondary oxidation products of lipids (35). Acrolein was also found to form in vivo by the metal-catalyzed oxidation of polyunsaturated fatty acids including arachidonic acid (36).
Acrolein Formation from Amino Acids, Proteins and Carbohydrates
Several sources for the formation of acrolein are known. It may arise from degradation of amino acids and proteins (37, 38), from degradation of carbohydrates (39), and from the Maillard reaction between amino acids or proteins and carbohydrates (40, 41). Many possible routes for the formation of this three-carbon aldehyde—taking the starting point from many different sugars or amino acids—may be proposed. Its formation from methionine by the Strecker degradation in the frame of the Maillard reaction is one example. Alanine, with its tree-carbon skeleton, has also been suggested as a possible source. However, fission reactions of longer carbon chains are common and well-known, so at present there is no basis to give priority to any specific reaction routes.
Formation of Acrylamide Through Amino Acid Reactions not Involving Acrolein
There are also numerous, plausible reaction routes by which amino acids (or proteins) may form acrylamide without going through acrolein. Within the frame of complex, multistage reaction mechanisms, involving hydrolyses, rearrangements, decarboxylations, deaminations etc., many specific mechanistic pathways may be suggested. Decarboxylation and deamination of aspargine, and transformations of dehydroalanine (formed from e.g. serine or cysteine) are some examples of reaction routes that have been proposed. But also in this case these can only be seen as possible examples, and similarly to above, there is no basis to give priority to any specific routes.
Conclusion
Since no systematic studies have been performed or reported, there is at present no evidence to point out any specific reaction routes for acrylamide formation, or to exclude any possibilities. Most probably a multitude of reaction mechanisms is involved, depending on food composition and processing conditions.
Further Reactions of Formed Acrolein and Acrylamide
As mentioned above, acrolein can be converted into acrylamide by a series of fundamental reactions. However, both acrolein and acrylamide are reactive, because of their double bonds and the amino group of acrylamide. They can readily react further with other reactive groups present in the food matrix or formed during the heating process. For example, acrylamide can react with small reactive molecules, such as urea (CO(NH2) 2 ) and formaldehyde (HCHO), or with glyoxal ((CHO)2), aldehydes (RCHO), amines (R2NH), thiols (RSH) etc. Furthermore, the products shown in the following scheme can even react further in the same mode of reaction.
These types of reactive functional groups may also be found in macromolecules, such as proteins, for instance. (Cf adduct formation with valine in the globin chain of hemoglobin described above. In hemoglobin adducts are formed not only with valine, but also with e.g. cystein.) The presence or absence of reactive groups (or its concentration) in the food matrix may thus be one explanation of differences in final acrylamide content in different food systems. The resulting acrylamide level may be due to a balance between formation and further reactions. The low acrylamide levels in heated meat products could, for instance, depend on adduct formation between acrylamide (or acrolein) and proteins.
Factors with Possible Influence on Acrylamide Formation
A couple of different chemical mechanisms for the formation of acrylamide have been outlined above. Obviously, as long as the mechanism or mechanisms are not confirmed, the influencing factors can not be established. Thus, what is presented here are attempts to identify what factors would be of importance (regarding processing conditions or product composition) if a specific reaction route is the prevailing one. Specific emphasis is put on the Maillard reaction, since this reaction system involves many of the basic carbohydrate and amino acid reactions. Another major reaction in foods during processing, which could be of importance, is lipid hydrolysis followed by oxidation of the fatty acids.
Acrolein Formation from Lipids
Acrolein may be formed from the glycerol part of triglycerides or through oxidation of fatty acids. This means that factors favouring lipid hydrolysis as well as factors favouring lipid oxidation would promote acrolein formation. Temperature is an important factor for both these reactions. Regarding hydrolysis, pH may also be of importance and high as well as low pH may be supposed to favour acrolein formation. Regarding oxidation, lipid composition is of key importance; the higher the degree of unsaturation, the lower the stability. Protection against oxygen and light will limit the oxidation and prooxidants, such as metals, should be avoided. The protective effect of antioxidants should also be taken into account.
The Maillard Reaction as the Route for Acrylamide Formation
The Maillard reaction has been proposed as a route for acrolein formation. Also the direct formation of acrylamide through amino acid transformations has been proposed. These amino acid transformations also involve reactions common in the Maillard reaction system.
Maillard Reaction Basics
The Maillard reaction (MR) is one of the most important chemical reactions in food processing, with influence on several aspects of food quality. Flavour, colour and nutritional value may be affected and certain reaction products have been noticed to be antioxidative, antimicrobial, genotoxic etc. The practical applications of Maillard chemistry in food processing are, therefore, a matter of balance between favourable and unfavourable effects, and the aim of the food manufacturer is to find an optimum in this balance. This may be accomplished by influencing the main variables affecting the MR (42).
The Maillard reaction takes place in 3 major stages and is dependent upon factors, such as concentrations of reactants and reactant type, pH, time, temperature, and water activity. Free radicals and antioxidants are also involved (43).
The early stage (step 1) involves the condensation of a free amino group (from free amino acids and/or proteins) with a reducing sugar to form Amadori or Heyns rearrangement products. The advanced stage (step 2) means degradation of the Amadori or Heyns rearrangement products via different alternative routes involving deoxyosones, fission or Strecker degradation. A complex series of reactions including dehydration, elimination, cyclization, fission and fragmentation result in a pool of flavour intermediates and flavour compounds. Following the degradation pathway as illustrated schematically in FIG. 6 , key intermediates and flavour chemicals can be identified.
One of the most important pathways is the Strecker degradation in which amino acids react with dicarbonyls (formed by the Maillard reaction) to generate a wealth of reactive intermediates. Typical Strecker degradation products are aldehydes, e.g. formaldehyde, acetaldehyde, and possibly propenaldehyde (acrolein). Strecker degradation results in degradation of amino acids to aldehydes, ammonia and carbon dioxide (44) and takes place in foods at higher concentrations of free amino acids and under more drastic reactions, e.g. at higher temperatures or under pressure (45). Pathways of formation of key flavour intermediates and products in the Maillard reaction (43) are shown in FIG. 6 .
The final stage (stage 3) of the MR is characterized by the formation of brown nitrogenous polymers and co-polymers. While the development of colour is an important feature of the reaction, relatively little is known about the chemical nature of the compounds responsible. Colour compounds can be grouped into two general classes—low molecular weight colour compounds, which comprise two to four linked rings, and the melanoidins, which have much higher molecular weights.
Review of Factors Influencing the Maillard Reaction
Factors that are particularly important for the MR are the starting reactants, e.g. type of sugar and amino acid (protein), time, temperature and water activity. Presence of metal salts (pro-oxidants), and inhibitors, like antioxidants and sulphite, might all have an impact.
Starting Reactants—Reducing Sugar and Amino Acids/Proteins
MR requires reducing sugars, i.e. sugars containing keto- or aldehydes (free carbonyl groups). The reactivity of different sugars can be summarised in the following way (46):
The shorter carbon chain, the sugar has, the greater are the lysine losses (MR). Pentoses are more reactive than hexoses and disaccharides in yielding brown colour. Aldoses are more reactive than ketoses both in aqueous solution model systems and at storage (low water content) Among isomeric sugars, stereochemistry is important. Thus ribose is more reactive than xylose monitored as lysine losses.
All monosacharides are reducing sugars. (Sugar alcohols do not participate in MR.) Among the disaccharides all sugars except sucrose are reducing sugars. In oligosaccharides and starch only the end-terminal monosaccharide is a reducing sugar. Starch and sugars, such as sucrose, lactose, maltose etc can easily hydrolyse upon heating above 100° C. at slightly acidic pH, resulting in the formation of monosaccharides (reducing sugars). Thus, thermal processing often result in a continuous supply of reducing sugar formed from complex carbohydrates.
Most studies concerning reactivity of amino acids have been performed on free amino acids in diluted aqueous solutions. The reactivity among the diamino acids increased with the length of the carbon chain. Among the amino acids studied lysine was most reactive. In proteins and peptides, only free amino groups can react, i.e. N-terminal á-amino groups and -amino groups.
Temperature and Time
The temperature dependence of chemical reactions is often expressed as the activation energy, Ea, in the Arrhenius equation. The higher the value of Ea, the more temperature dependent is the reaction rate. Activation energy data for the MR have been reported within a wide range, 10-160 kJ/mole, depending on, among other things, water activity and pH and what effect of the reaction has been measured. The temperature dependence of the MR is also influenced by the participating reactants. The temperature effect is also affected by the other variables and different aspects of the MR thus differ in temperature dependence (42).
Water
Water has both an inhibitory and an accelerating impact on the MR. Water acts partly as a reactant and partly as a solvent and transporting medium of reactants (reactant mobility). In the initial steps of the MR, 3 moles of water are formed per mol carbohydrate. Thus the reaction occurs less readily in foods with a high aw value. Water might depress the initial glucosylamine reaction, but enhance the deamination step later in the reaction.
The results from studies in model systems for optimal water concentration or water activity (free water) or relative humidity (RH) vary markedly depending on selected reactants and how the MR is evaluated—as loss in lysine or browning intensity. Several studies have been performed of which most claim the max aw to be between 0.3 and 0.7 (47). However, most data on the aw influence are based on studies at relatively low temperatures (30-60° C.). At higher temperature, more relevant to heat processes, considerably lower aw has been shown to be favourable to the MR (42).
The main explanation to an optimum reaction rate at an intermediate aw is that the reactants are diluted at the higher aw, while at a lower aw the mobility of reactants is limited, despite their presence at increased concentrations.
pH
The MR itself has a strong influence on pH. Therefore, aqueous model systems based on reflux boiling of sugars and amino acids need to be buffered since the pH quickly drops from 7 to 5. Low pH values (<7) favour the formation of furfurals (from Amadori rearrangement products), while the routes for reductones and fission products are preferred at a high pH.
However, the overall effect of pH is not clear cut, since the reactions take place by all the three pathways. In unbuffered water solutions, pH decrease during MR and buffering with alkali has a catalytic effect.
Reactivity of different amino acids at various pHs has been studied. Browning of a glucose solution upon heating was obtained first when pH exceeded 5 and it increased with increasing pH. The degree of browning varied with the position of the amino group. The function of pH is linked with specific reaction steps of the MR. Initially only non-protonised forms of amino acids a can form Schiff's base. This explains the pronounced changes in reactivity (monitored as browning) which happens when pH passes the isoelectric point of the amino group in the reacting amino acid. Thus, optimal pH for the MR varies with the system used and how the reaction is monitored (e.g. lysine losses or browning).
Inhibition of the Maillard Reaction
Measures to inhibit the Maillard reaction in cases where it is undesirable, involve lowering of the pH value, maintenance of lowest possible temperatures and avoidance of critical water contents (moistures below 30%, during processing and storage), use of non-reducing sugars, and addition of sulphite (45). The use of the inhibitor, sulphur dioxide, constitutes an important way of controlling the Maillard reaction. It may combine with early intermediates. However, sulphite only delays colour formation and it is interesting to note that the colour formed in sulphite-treated systems is less red and more yellow than in untreated systems.
Maillard Reactions and Food Processing
In exploiting the Maillard reaction, the key target for the food industry is to understand and harness the reaction pathways enabling improvement of existing products and the development of new products. While it would be easy to assume that this means the generation of flavour and colour, not all Maillard products endow positive characteristics to foods and ingredients. The positive contributions of the MR are flavour generation and colour development. The negative aspects are off-flavour development, flavour loss, discoloration, loss of nutritional value and formation of toxic Maillard reaction products (MRPs). In applying the MR, there are challenges that are common to the food industry, independent of the type of the product. These challenges can be classified as follows: maintenance of raw material quality; maintenance of controlled processes for food production; maintenance of product quality; extension of product shelf-life (42, 43).
Flavour/Aroma
The most common route for formation of flavours via the MR comprises the interaction of á-dicarbonyl compounds (intermediate products in the MR, stage 2) with amino acids through the Strecker degradation reactions. Alkyl pyrazines and Strecker aldehydes belong to commonly found flavour compounds from MR. For example, low levels of pyrazines are formed during the processing of potato flakes when the temperature is less than 130° C., but increases tenfold when the temperature is increased to 160° C., and decreases at 190° C., probably due to evaporation or binding to macromolecules. The aroma profile varies with the temperature and the time of heating. At any given temperature-time combination, a unique aroma, which is not likely to be produced at any other combination of heating conditions, is produced. Temperature also affects the development of aroma during extrusion cooking
Colour
The coloured products of the Maillard reaction are of two types: the high molecular weight macromolecule materials commonly referred to as the melanoidines, and the low molecular weight coloured compounds, containing two or three heterocyclic rings (48). Colour development increases with increasing temperature, with time of heating, with increasing pH and by intermediate moisture content (aw=0.3-0.7). Generally, browning occurs slowly in dry systems at low temperatures and is relatively slow in high-moisture foods. Colour generation is enhanced at pH>7. Of the two starting reactants, the concentration of reducing sugar has the greatest impact on colour development. Of all the amino acids, lysine gives the largest contribution to colour formation and cysteine has the least effect on colour formation.
Antioxidative Capacity
There are several reports on the formation of antioxidative MRPs in food processing. The addition of amino acids or glucose to cookie dough has been shown to improve oxidative stability during the storage of the cookies. Heat-treatment of milk product prior to spray drying has been reported to improve storage stability as has heat treatments of cereals (42).
The antioxidant effect of the MRP has been extensively investigated (49). It has been reported that the intermediate reductone compounds of MRP could break the radical chain by donation of a hydrogen atom: MRP was also observed to have metal-chelating properties and retard lipid peroxidation. Melanoidines have also been reported to be powerful scavengers of reactive oxygen species (50). Recently, it was suggested that the antioxidant activity of xylose-lysine MRPs may be attributed to the combined effect of reducing power, hydrogen atom donation and scavenging of reactive oxygen species (51).
Nutritive Value
Loss in protein quality is often associated with the MR, especially in cereal products and milk powder produced by heat-treatment. Usually the essential amino acid having an extra free amino group, e.g. lysine, is most vulnerable. If the essential amino acid also is the nutritionally limiting amino acid, the influence of MR on the protein quality is substantial. This is not a problem in cooking meat and fish, since these food items are very rich in protein. Loss of protein quality in terms of nutritional value is a more serious problems for heat-treatment and dehydration of especially cereals, milk and their mixtures (breakfast cereals, gruels, bread, biscuits), since carbohydrates dominates over proteins in these food items and the proteins levels are also generally low.
Toxic Effects
The possibilities that MPR could be mutagenic and/or carcinogenic were explored with Ames test, around 20-25 years ago. In general weak genotoxicity/mutagenic activities were found for known MPRs. Most attention over the past decades has been paid on the food mutagens found in the crust from cooked meat and fish. Chemically, these compounds belong to a class of heterocyclic amines, currently amounting to around 20 different species. Most of them have been classified as possible food carcinogens (group 2B) according to the International Agency for Research in Cancer (IARC) based on long-term studies on rodents. The precursors of the heterocyclic amines are free amino acids and for more than half of the 20 species, also creatine (a natural energy metabolite present in muscle cells only). Reducing sugars up to equimolar amounts compared with amino acids and/or creatine enhance the yields of heterocyclic amines markedly.
Thus MR and/or pyrolysis have been claimed to be important mechanisms for the formation of these heterocyclic amines, where Strecker aldehydes, pyrazines or pyridines and creatine have been suggested to play an important role. The yields of these food borne carcinogens are increasing with time and temperature, especially from 150° C. and above. The highest concentrations of heterocyclic amines are found in the crust of pan-fried, grilled or barbecued meat and fish. In addition, gravies prepared from dried meat-juice collected from pan-residues or oven-roasting could be rich in heterocyclic amines. Pro-oxidants, water activity in the optimal range for the MR, and high temperatures (200-400° C.) enhance their yield. The average daily exposure for heterocyclic amines is around 0.5 μg/day and person, with a range between 0-20 μg. Antioxidants, excess of carbohydrates, cooking temperatures below 200° C. and moisture contents above 30% reduce the occurrence of heterocyclic amines. Moreover, heterocyclic amines rarely occur in plant foods even during well-done cooking (52).
There is to our knowledge no report in the literature yet concerning acrylamide formation linked with the MR.
APPENDIX 2
Nonenzymic Browning
The nonenzymic browning or Maillard reaction is of great importance in food manufacturing and its results can be either desirable or undesirable. An example of the first kind is the brown crust formation on bread and one of the second kind is the brown discoloration of evaporated and sterilized milk. In products in which the browning reaction is favorable, the resulting color and flavor characteristics are generally experienced as pleasant. In other products, color and flavor become quite unpleasant.
The browning reaction can be defined as the sequence of events which begins with the reaction of the amino group of amino acids, peptides or proteins with a glycosidic hydroxyl group of sugars and terminates with the formation of brown nitrogenous polymers or melanoidins.
The reaction velocity and pattern are influenced in the first place by the nature of the reacting amino acid or protein and of the carbohydrate. This means that each kind of food may show a different browning pattern. Generally, lysine is the most reactive amino acid because of the free ε-amino group. Since lysine is the limiting essential amino acid in many food proteins, its destruction is of vital importance and can result in substantial reduction of the nutritional value of the protein. Foods which are rich in reducing sugars are very reactive, and this explains that lysine in milk is destroyed more easily than in other foods ( FIG. 7 ). Other factors which influence the browning reaction are: temperature, pH, moisture level, oxygen, metals, phosphates, sulfur dioxide and other inhibitors.
The browning reaction involves a number of steps and an outline of the total pathway of melanoidin formation has been given by Hodge (1953) shown in FIG. 8 . According to Hurst (1972) five steps are involved in the process:
1. The production of an N-substituted glycosylamine from an aldose or ketose reacting with a primary amino group of an amino acid, peptide or protein. 2. Rearrangement of the glycosylamine by an Amadori rearrangement type of reaction to yield an aldoseamine or ketoseamine. 3. A second rearrangement of the ketoseamine with a second mole of aldose to result in the formation of a diketoseamine, or the reaction of an aldoseamine with a second mole of amino to yield a diamino sugar. 4. Degradation of the amino sugars with loss of one or more molecules of water to give amino or nonamino compounds. 5. Condensation of the compound formed in step 4 with each other or with amino compounds with formation of brown pigments and polymers.
The formation of glycosylamines from the reaction of amino groups and sugars is reversible ( FIG. 9 ) and the equilibrium is highly dependent on the moisture level present. The mechanism as shown is thought to involve addition of the amine to the carbonyl group of the open-chain form of the sugar, elimination of a molecule of water, and closure of the ring. The rate is high at low water content and this explains the ease of browning in dried and concentrated foods.
The Amadori rearrangement of the glycosylamines involves the presence of an acid catalyst and leads to the formation of ketoseamine or 1-amino-1-deoxyketose according to the scheme of FIG. 10 . In the reaction of D-glucose with glycine the amino acid reacts as the catalyst and the compound produced is 1-deoxy-1-glycino-β-D-fructose ( FIG. 11 ). The ketoseamines are relatively stable compounds which are formed in maximum yield in systems with 18% water content (Shallenberger and Birch 1975). A second type of rearrangement reaction is the Heyns rearrangement which is an alternative to the Amadori rearrangement and leads to the same type of transformation. The mechanism of the Amadori rearrangement ( FIG. 10 ) involves protonation of the nitrogen atom at carbon 1. The Heyns rearrangement ( FIG. 12 ) involves protonation of the oxygen at carbon 6.
Secondary reactions lead to the formation of diketoseamines and diamino sugars. The formation of these compounds involves complex reactions and in contrast to the formation of the primary products does not occur on a mole for mole basis.
In the following step, the ketoseamines are decomposed by 1,2-enolization or 2,3-enolization. The former pathway appears to be the more important one in the formation of brown color whereas the latter results in the formation of flavor products. According to Hurst (1972), the 1,2-enolization pathway appears to be the main one leading to browning but also contributes to formation of off-flavors through hydroxymethylfurfural, which may be a factor in causing the off-flavors in stored, overheated or dehydrated food products. The mechanism of this reaction is shown in FIG. 13 (Hurst 1972). The ketoseamine (1) is protonated in acid medium to yield (2). This is changed in a reversible reaction into the 1,2-enolamine (3) and this is assisted by the N substituent on carbon No. 1. The following steps involve the β-elimination of the hydroxyl group on carbon No. 3. In (4) the enolamine is in the free base form and converts to the Schiff base (5). The Schiff base may undergo hydrolysis and form the enolform (7) of 3-deoxyosulose (8). In another step the Schiff base (5) may lose a proton and the hydroxyl from carbon No. 4 to yield a new Schiff base (6). Both this compound and the 3-deoxyosulose may be transformed into an unsaturated osulose (9), and by elimination of a proton and a hydroxyl group, hydroxymethylfurfural (10) is formed.
Following the production of 1,2-enol forms of aldose and ketose amines, a series of degradations and condensations results in the formation of melanoidins. The α-β-dicarbonyl compounds enter into aldol type condensations which lead to the formation of polymers, initially of small size, highly hydrated and in colloidal form. These initial products of condensation are fluorescent and continuation of the reaction results in the formation of the brown melanoidins. These polymers are of non-distinct composition and contain varying levels of nitrogen. The composition varies with the nature of the reaction partners, pH, temperature and other conditions.
The flavors produced by the Maillard reaction also vary widely. In some cases, the flavor is reminiscent of carmelization. An important reaction contributing to the formation of flavor compounds is the Strecker degradation of α-amino acids. The dicarbonyl compounds formed in the previously described schemes react in the following manner with α-amino acids:
TABLE 3
AROMA AND STRUCTURE CLASSIFICATION OF BROWNED
FLAVOR COMPOUNDS
Aromas:
Burnt
Variable
(pungent, empyreumatic)
(aldehydic, ketonic)
Structures:
Polycarbonyls
Monocarbonyls (R—CHO, R—C:O—CH 3 )
Examples of
Glyoxal
Strecker aldehydes
compounds:
Pyravaldehyde
Isobutyric
Diacetyl
Isovsleric
Mesoxalic dialdehyde
Methional
Acrolein
2-Furaldehydes
Crotonaldehyde
2-Pyrrole aldehydes
C 3 -C 6 Methyl ketones
Source: Hodge et al. (1972).
The amino acid is converted into an aldehyde with one less carbon atom (Schönberg and Moubacher 1952). Some of the compounds of browning flavor have been described by Hodge et al. (1972). Corny, nutty, bready and crackery-aroma compounds consist of planar unsaturated heterocyclic compounds with one or two nitrogen atoms in the ring. Other important members of this group are partially saturated N-heterocyclics with alkyl or acetyl group substituents. Compounds that contribute to pungent, burnt aromas are listed in Table 3. These are mostly vicinal polycarbonyl compounds and α,β-unsaturated aldehydes. They condense rapidly to form melanoidins. The Strecker degradation aldehydes contribute to the aroma of bread, peanuts, cocoa and other roasted foods. Although acetic, phenylacetic, isobutyric and isovaleric aldehydes are prominent in the aromas of bread, malt, peanuts and cocoa, they are not really characteristic of these foods (Hodge et al. 1972).
A somewhat different mechanism for the browning reaction has been proposed by Burton and McWeeney (1964) and is shown in FIG. 14 . After formation of the aldosylamine, dehydration reactions result in the production of 4- to 6-membered ring compounds. When the reaction proceeds under conditions of moderate heating, fluorescent nitrogenous compounds are formed and these react rapidly with glycine to yield melanoidins.
The influence of reaction components and reaction conditions results in a wide variety of reaction patterns. Many of these conditions are interdependent. Increasing temperature results in a rapidly increasing rate of browning, and not only reaction rate, but also the pattern of the reaction may change with temperature. In model systems, the rate of browning increases 2-3 times for each 10° rise in temperature. In foods containing fructose, the increase may be 5 to 10 times for each 10° rise. At high sugar contents, the rate may be even more rapid. Temperature also affects the composition of the pigment formed. At higher temperatures, the carbon content of the pigment increases and more pigment is formed per mole of carbon dioxide released. Color intensity of the pigment increases with increasing temperature. The effect of temperature on the reaction rate of D -glucose with DL -leucine is demonstrated in FIG. 15 .
In the Maillard reaction, the basic amino group disappears and, therefore, the initial pH or the presence of a buffer has an important effect on the reaction. The browning reaction is slowed down by decreasing pH, and the browning reaction can be said to be self-inhibitory since the pH decreases with the loss of the basic amino group. The effect of pH on the reaction rate of D -glucose with DL -leucine is demonstrated in FIG. 16 . The effect of pH on the browning reaction is highly dependent on moisture content. When a large amount of water is present, most of the browning is caused by caramelization, but at low water levels and at pH greater than 6, the Maillard reaction is predominant.
The nature of the sugars in a nonenzymic browning reaction determines their reactivity. Reactivity is related to their conformational stability or to the amount of open-chain structure present in solution. Pentoses are more reactive than hexoses, and hexoses more than reducing disaccharides. Nonreducing disaccharides only react after hydrolsys has taken place. The order of reactivity of some of the aldohexoses is mannose>galactose>glucose.
The effect of the type of amino acid can be summarized as follows. In the α-amino acid series, glycine is the most reactive. Longer and more complex substituent groups reduce the rate of browning. In the ω-amino acid series, browning rate increases with increasing chain length. Ornithine browns more rapidly than lysine. When the reactant is a protein, particular sites in the molecule may react faster than others. In proteins, the ε-amino group of lysine is particularly vulnerable to attack by aldoses and ketoses.
Methods of preventing browning could consist of measures intended to slow reaction rates, such as control of moisture, temperature or pH or removal of an active intermediate. Generally, it is easier to use an inhibitor. One of the most effective inhibitors of browning is sulfur dioxide. The action of sulfur dioxide is unique and no other suitable inhibitor has been found. It is known that sulfite can combine with the carbonyl group of an aldose to give an addition compound:
NaHSO 3 +RCHO→RCHOHSO 3 Na
but this reaction cannot possibly account for the inhibitory effect of sulfite. It is thought that sulfur dioxide reacts with the degradation products of the amino sugars which prevents these compounds from condensation into melanoidins. A serious drawback of the use of sulfur dioxide is that it reacts with thiamine and proteins, thereby reducing the nutritional value of foods. Sulfur dioxide destroys thiamine and is, therefore, not permitted for use in foods containing this vitamin.
Chemical Changes
During processing and storage, a number of chemical changes may occur in food proteins, some of which are desirable, others undesirable. Such chemical changes may lead to compounds which are non-hydrolyzable by intestinal enzymes or to modification of the peptide side chains which render certain amino acids unavailable. Mild heat treatments in the presence of water can significantly improve the nutritional value in some cases. Sulfur-containing amino acids may become more available and certain antinutritional factors such as the trypsin inhibitors of soybeans may be deactivated. Excessive heat in the absence of water can be detrimental to protein quality, e.g., in fish proteins tryptophan, arginine, methionine and lysine may be damaged. A number of chemical reactions may take place during heat treatment including decomposition, dehydration of serine and threonine, loss of sulfur from cysteine, oxidation of cysteme and methionine, cyclization of glutamic and aspartic acid and threonine (Mauron 1970).
One of the most important changes resulting in decomposition of certain amino acids is the non-enzymic browning reaction or Maillard reaction. For this reaction, the presence of a reducing sugar is required. Heat damage may also occur in the absence of sugars. Bjarnason and Carpenter (1970) demonstrated that heating of bovine plasma albumin for 27 hours at 115° C. resulted in a 50% loss of cystine and 4% of lysine. These authors suggest that amide type bonds are formed by reaction between the ε-amino group of lysine and the amide groups of asparagine or glutamine, with the reacting units present either in the same peptide chain or in neighboring ones.
Some amino acids may be oxidized by reacting with free radicals formed by lipid oxidation. Methionine can react with a lipid peroxide to yield methionine sulfoxide. Cysteine can be decomposed by a lipid free radical according to the following scheme in FIG. 17 .
All publications mentioned in the above specification are herein incorporated by reference. Various modifications and variations of the described methods and system of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in chemistry or related fields are intended to be within the scope of the following claims. | There is provided a process for the prevention and/or reduction of acrylamide formation and/or acrylamide precursor formation in a foodstuff containing (i) a protein, a peptide or an amino acid and (ii) a reducing sugar, the process comprising contacting the foodstuff with an enzyme capable of oxidizing a reducing group of the sugar. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for hooking between a heddle frame and a lever actuated by a weave system. It also relates to a weaving loom equipped with such a device.
2. Description of the Related Art
In order to simply the operations of mounting and dismantling of the heddle frames on a weaving loom, it is known to use connecting devices arranged to ensure, semi-automatically, the hooking and unhooking of the frames with respect to the levers of the system. Such a device is disclosed in EP-A-0 117 826 in which an open hook is configured to cooperate with a polygonal ring, this hook being provided with two plates forming a catch for locking the ring. These plates are arranged on either side of an arm of the hook on which they are articulated. Each plate has a relatively small thickness and the arm on which they are articulated must also present a relatively small thickness with respect to the rest of the hook and with respect to the width of the ring, in order to allow these plates to align with the ring. Due to the small thickness of the plates, the contact surfaces of these plates and of the ring are relatively reduced, which, taking into account the usual vibrations in a weaving loom, leads to premature wear of the plates and/or of the ring. In addition, the pivot pin of the plates on the hooks also tends to wear out due to these vibrations. Furthermore, a traction spring is provided for exerting on the plates an effort tending to return them towards a position of locking of the ring. Such a spring tends to wear out and may break at the level of its attachments on the hook and/or on an element fast with the plates. Finally, rivets must be provided for assembling the plates together and on the hook, such rivets having to be positioned with care, which reduces productivity of a method for manufacturing such a device. These drawbacks limit the performances of a loom equipped with devices of this type.
It is a more particular object of the invention to overcome these drawbacks by proposing a hooking device which is as easy to use as that of the prior state of the art and in which the risks of premature wear are substantially reduced.
SUMMARY OF THE INVENTION
To that end, the invention relates to a device for hooking between a heddle frame and a lever actuated by a weave system, this device comprising a ring of substantially polygonal section, fast with the frame or with the lever, and an open hook, provided with bearing surfaces arranged to cooperate with the section of the ring and fast with the lever or the frame, certain of these bearing surfaces being parallel to one another and adapted to ensure, by cooperation with two surfaces of the ring likewise parallel to one another, the essential of the transmission of effort between the lever and the heddle frame, while the hook is equipped with a member for locking the ring in position engaged in the hook, the bearing zone of the locking member against the ring being located substantially between an axis of articulation of the ring on the frame or on the lever and an axis of articulation of the locking member on the hook, characterized in that the locking member is constituted by a lock forming a pivot pin received in a cavity formed in the thickness of the hook, this lock presenting a surface adapted to interact with the ring and of width substantially equal to the width of the ring.
Thanks to the invention, the lock can bear on the polygonal ring over substantially the whole width of this ring, which substantially increases the area of contact with respect to the known devices. The fact that the lock forms a pivot pin received in a cavity of the hook avoids having to use an added pin, such as a rivet, and induces an efficient transmission of effort between the lock and the hook. The fact that the bearing zone of the lock against the ring is located substantially between the axes of articulation of the ring and of the lock, means that the lock works essentially in compression, which enables it to be particularly efficient. In addition, as the essential of the efforts transmitted by the lever to the frame passes through the bearings and the parallel surfaces provided respectively on the hook and on the ring, the lock is not under permanent strain.
According to advantageous aspects of the invention, the device incorporates one or more of the following characteristics:
The lock is made of self-lubricating steel, for example a sintered steel. This makes it possible to limit the frictions at the level of the surfaces of the lock and the ring in contact and at the level of the contact surfaces of the pin and the cavity in which it is received.
The lock and the hook together define a volume for receiving a compression spring, this volume, defined in the thickness of the lock and the hook, being of variable size as a function of the relative position of the lock and of the hook. Thanks to this aspect of the invention, the spring does not present attachments likely to break and may be protected from the outside environment.
A maneuvering member is clipped on the lock and comprises a tab on which a user may exert an effort or force for controlling the pivoting of the lock with respect to the hook.
An element for containment of a volume defined between the hook and the lock comprises two cheeks disposed on either side of the hook and the lock. This containment element makes it possible to isolate the aforementioned volume and, if necessary, the spring that it contains. Reserves of grease may be provided in the cavities formed between the lock and the hook, particularly in the vicinity of the pin. It may thus be envisaged to force-feed lubricant in the zone of articulation between the lock and the pin. The containment also makes it possible to protect the zones full of grease from pollution such as flock. In that case, the containment element is advantageously constituted by the maneuvering member which is constituted by a plastic part. In addition, the maneuvering member may be provided to form a pin extending between the aforementioned cheeks and adapted to pivot in a cavity formed in the thickness of the lock.
The maneuvering member forms a beak for elastically clipping on a concave part of the lock oriented opposite that surface of the lock provided to interact with the ring. This mode of fixation of the maneuvering member on the lock allows a rapid and reliable assembly while providing a possibility of dismantling, particularly for fresh lining of grease along the internal cavities of the device.
The ring is equipped with an integrated lubricator, this ring and this lubricator being made in one piece, of plastics material. The lubricator may be mobile between two positions, oriented at 180° with respect to each other about the central axis of the ring, while the plates for connecting the ring to the frame on which it is mounted may be stamped with a setback at the level of the edge of the ring, with the result that the width of the ring may be increased without substantially increasing the overall dimensions of the device.
The ring bears an element in relief for indexing, adapted to cooperate with at least one plate of a pair of plates between which the ring is mounted, with the result that the angular clearance of the ring with respect to these plates is limited.
The invention also relates to a weaving loom equipped with a hooking device as described hereinbefore. Such a weaving loom is easier to use than those of the prior state of the art, while its maintenance is facilitated and the life of the devices that it comprises is substantially increased over that of known looms. The performances of such a loom are substantially improved with respect to those of the prior art looms.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more readily understood on reading the following description of an embodiment of a hooking device in accordance with its principle, given solely by way of example and made with reference to the accompanying drawings, in which:
FIG. 1 is a side view with parts torn away at the level of the ring of a hooking device according to the invention before the hook is hooked on the polygonal ring.
FIG. 2 is a section on a larger scale along line II—II of FIG. 1 .
FIG. 3 is a view similar to FIG. 1, with additional parts torn away at the level of the hook, while the hook is in place on the ring.
FIG. 4 is an exploded view in perspective of certain elements constituting the device of FIGS. 1 to 3 .
FIG. 5 is a view similar to FIG. 1 while the device is in another configuration of use, and
FIG. 6 is a view in perspective of the lock of the device of FIGS. 1 to 5 .
DESCRIPTION OF PREFERRED EMBODIMENT
Referring now to the drawings, a heddle frame 1 of a weaving loom is represented by its lower upright in the Figures and constitutes a part of a weaving loom M.
On this frame 1 are mounted, by means of a bar 2 , two plates 3 and 3 ′ between which is arranged a ring 4 of substantially hexagonal section. The ring 4 presents a metal pin 5 crimped on the plates 3 and 3 ′. The ring 4 is moulded from self-lubricating plastics material.
The ring 4 is in one piece with a lubricator 6 for force-feeding the zone of contact between the ring 4 and the pin 5 with a lubricant. It is noted that the ring 4 may rotate about pin 5 , with the result that the lubricator 6 may be disposed in the position shown in solid lines or in the position shown in broken lines in FIG. 1, depending on the scheduled direction of cooperation with a hook.
As is more clearly visible in FIG. 2, the plates 3 and 3 ′ are stamped at the edges of the ring 4 , with the result that they form zones 7 and 7 ′ separated by a distance d greater than the distance d 0 separating the plates 3 and 3 ′ at their joint with the bar 2 . The width 14 of the ring 4 , which is substantially equal to the distance d, is thus greater than the distance d 0 which is linked with the width of the head 12 .
The ring 4 is partially engaged in two stamped portions 30 and 30 ′ respectively forming the zones 7 and 7 ′ on the plates 3 and 3 ′ and defining therebetween the volume for receiving the ring 4 .
The lubricator 6 is provided with two lateral studs 61 and 61 ′ intended to be engaged in lateral extensions 31 and 31 ′ of the stamped portions 30 and 30 ′. The extensions 31 and 31 ′ form grooves for receiving the studs 61 and 61 ′ facing towards the centre of the volume defined between these plates.
The studs 61 and 61 ′ are in one piece with the lubricator 6 and the ring 4 .
At the level of the extensions 31 and 31 ″, the distance d 1 between the plates 3 and 3 ′ is equal to the distance d and greater than width 1 1 of the lubricator 6 at the level of the studs 61 and 61 ′. In this way, the studs may be displaced in the width of the extensions 31 and 31 ′ without rubbing against the plates, this allowing a limited angular clearance of the ring 4 about the geometrical axis X 5 of the pin 5 . When it is desired to tilt the ring 4 from the position represented in solid lines to the one represented in broken lines in FIG. 1, the studs 61 and 61 ′ are slid, by means of an effort allowing the studs 61 and 61 ′ to be extracted from the extensions 31 and 31 ′, against the opposite surfaces of the plates 3 and 3 ′ outside the stamped portions 30 and 30 ′, so as to bring them in those parts of the extensions 31 and 31 ′ located to the left of FIG. 1, only deformation 31 ′ being visible in this Figure. A movement in the opposite direction remains, of course, possible.
The lubricator 6 might, of course, bear only one stud, the two plates 3 and 3 ′ being able to remain identical in order to simplify manufacture of the device. One sole stud cooperating with one sole extension suffices, in fact, to limit the angular clearance of the ring 4 .
A hook 10 is in one piece with or welded on a lever 11 actuated by a weave system such as a dobby. The hook 10 comprises a head 12 defining a housing 13 for receiving the ring 4 , the housing 13 being bordered by surfaces 14 1 , 14 2 , 14 3 and 14 4 adapted to come respectively into engagement with surfaces 4 1 , 4 2 , 4 3 and 4 4 of the edge of the ring 4 .
The efforts for placing the frame 1 in motion are substantially perpendicular to the bearing surfaces 14 1 , and 14 4 and to surfaces 4 1 and 4 4 , as represented by the arrows of movement M 1 , and M 2 in FIG. 3 . Taking into account the geometry of the bearing surfaces 14 1 , and 14 4 and of surfaces 4 1 , and 4 4 which are parallel to one another, the efforts for placing the frame 1 in motion essentially transit via these bearing surfaces and surfaces. In particular, the ring 4 does not tend to be driven from the housing 13 .
As the ring 4 may have a certain angular clearance about axis X 5 , the surfaces 4 1 , and 4 4 may remain perpendicular to the efforts M 1 , and M 2 , including in the case of the lever 11 tending to oscillate perpendicularly to the vertical in the plane of FIGS. 1, 3 and 5 .
The hook 10 is also provided with an arm 15 on which is mounted a lock 16 enabling the ring 4 to be retained in the configuration of FIG. 3 .
The lock 16 comprises a surface 161 intended to come into contact with a lateral surface 4 5 of the ring 4 , the surface 161 having a width 1 substantially equal to the thickness e of the lock 16 which is itself substantially equal to the thickness e′ of the metal sheet from which the hook 10 is cut out. In practice, the width 1 is substantially equal to, and preferably slightly smaller than, the width 1 4 . A surface bearing of the surfaces 161 and 4 5 is possible over the area of the surface 161 .
The lock 16 comprises a tab 162 whose end 163 presents a partially cylindrical outer section, with the result that it may constitute a pivot pin in a cavity 151 made in the thickness e′ of the arm 15 and presenting a partially cylindrical shape.
X 1 , denotes the geometrical axis of the end 163 and X 2 the geometrical axis of the cavity 151 . When the lock 16 is mounted on the arm 15 , the axes X 1 and X 2 merge and the end 163 forms a pivot pin on the hook 10 , this pin being in one piece with the lock 16 .
As is more particularly visible in FIG. 3, when the ring 4 is in place in the housing 13 , the zone of abutment of the lock 16 on the ring 4 , i.e. the zone including the surfaces 161 and 4 5 , is located approximately between axes X 5 and X 1 . In this position, the lock 16 therefore works essentially in compression, as represented by arrows E 1 and E 2 which figure the efforts undergone by the lock 16 respectively from the ring 4 and the hook 10 .
As the ring 4 does not tend to be driven from the housing 13 under the effect of the setting in motion M 1 and M 2 , the lock 16 does not intervene systematically to counter the efforts of effort transmission but principally to ensure the relative engaged position of the hook and of the ring against the vibratory movements and the possible obliqueness of the hook. The lock 16 is therefore hardly stressed and the fact that it works in compression is very favourable from the mechanical standpoint in order to obtain an efficient locking of the ring 4 in the housing 13 .
The arm 15 forms a return 152 around the cavity 151 while a slot 164 is defined between the tab 162 and a rear part 165 of the lock 16 opposite the surface 161 . The geometry of the elements 152 and 164 is such that, when the lock 16 is in mounted configuration, the return 152 is engaged inside the slot 164 . The geometry of these elements limits a movement of tilting of the lock 16 about axes X 1 and X 2 in the trigonometric direction opposite to FIG. 3, i.e. in the direction of arrow F 1 .
The lock 16 defines a housing 166 for receiving one end 171 of a compression spring 17 of which the second end 172 is received in a housing 153 provided on the arm 15 . The housings 171 and 172 are formed in the thickness of the opposite edges of the elements 15 and 16 . The spring 17 is dimensioned such that it permanently exerts on the lock 16 an effort represented by arrow F 2 tending to tilt the lock 16 in the direction of arrow F 1 in FIG. 1 .
A maneuvering member 18 is formed by a piece made of molded plastic material which essentially comprises two plates 181 , 182 connected by a cylindrical pin 183 and by a bottom web 184 . The maneuvering member is also provided with a tab 185 allowing a user to exert an effort, represented by arrow F 3 in FIG. 5, tending to tilt the lock 16 about axes X 1 and X 2 , in the direction of arrow F′ 1 opposite to arrow F 1 .
The lock 16 is provided with a housing 167 for receiving the pin 183 , with possibility of rotation, while the web 184 is provided with a beak 186 intended to be engaged in a cavity 168 in the lock 16 oriented opposite the surface 161 . In this way, once the pin 183 is in place in the housing 167 , it is possible to pivot the member 18 about the geometrical axis X 3 of the pin 183 to immobilize the member 18 on the lock 16 .
When the member 18 is in place on the lock 16 , its plates 181 and 182 constitute two cheeks which isolate the volume V defined between the lock 16 and the arm 15 from the outside and in which the spring 17 and the pin 163 are disposed. In other words, the member 18 is an element for containment of the volume V which makes it possible to protect this volume against pollution and, in particular, against flock. The member 18 also makes it possible to retain within the volume V a lubricant such as grease, such a lubricant being able to be introduced in order to facilitate the articulation of the lock 16 on the arm 15 .
Once the member 18 is clipped on the lock 16 , an effort F 3 exerted by the user on the tab 185 has the effect of pivoting the lock 16 , by its pin 163 , into the cavity 151 against the effort F 2 . This makes it possible to retract the lock 16 which attains the position of FIG. 5 where the surface 161 is disengaged from the path of the ring 4 during uncoupling of the frame 1 and the lever 11 , the movement of the ring being represented by the arrow F 5 .
In this configuration, the upper surface 169 of the lock 16 which connects the surface 161 to the part 165 , is substantially aligned with the surface 144 , this facilitating the slide of the ring 4 which is in abutment on this surface 169 .
When it is desired to hook the frame 1 and the lever 11 , it suffices to displace the ring 4 towards the housing 13 , as represented by arrow F 6 in FIG. 1 . The ring 4 then comes into contact with the surface 169 and pushes the lock against the effort F 2 , this freeing passage for the ring 4 .
As soon as the ring has arrived in housing 13 , it ceases to interact with the lock 16 which is then pushed by the spring 17 towards the position of FIG. 3 .
The invention presents the particular advantage that the lock 16 , which presents a thickness e substantially equal to the thickness e′ of the rest of the hook 10 , is articulated on this hook without the use of a rivet likely to wear out prematurely. The mode of assembly of the member 18 on the lock 16 and of the lock 16 on the arm 15 provides for easy dismantling of these elements.
The invention has been shown with a ring presenting a substantially hexagonal section. The ring may, of course, be octogonal and, more generally, present any polygonal shape comprising two parallel surfaces for the transmission of effort between the lever and the ring, the other parts of the section of the ring being planar or curved, the geometry of the hook in that case being adapted thereto.
The invention has been shown with the ring fast with a heddle frame while the hook is fast with a drive lever. A reverse structure may, of course, be envisaged in which the ring is fast with a lever while the hook is fast with a heddle frame. | A device for connecting a heddle frame to a reciprocating lever in a weaving loom which device includes a hook defining a housing in which a ring is selectively seated. The ring is mounted to either the heddle frame or the lever and includes surfaces for cooperatively engaging bearing surfaces defined by the housing of the hook. A lock is provided which is pivotally mounted to the hook and is engageable to retain the ring within the housing of the hook. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
The subject matter of this application is related to the subject matter set forth in co-pending U.S. patent application No. 09/740,681, entitled “Adaptive Flag Weight For Document Handling Apparatus,” filed Dec. 19, 2000, which is assigned to the assignee of the application hereof.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to document handling devices, and more particularly, to an arrangement for adaptively driving a flag element of a document handling device.
2. Discussion
Document handling devices are commonly used today to quickly move and sort a variety of documents. Documents are often stacked and automatically fed from the document stack. A feeding mechanism is used to introduce each document to its document transport for processing and sorting. It is important to introduce each document singly, with consistent spacing, to permit the fastest feed rate possible while still maintaining proper document processing.
In high speed sorters, a hopper is often used to supply documents to the feeding mechanism. A device, commonly known as a flag, is used to move documents across the hopper during feeding. To create this movement, the flag applies a force to the last document in the stack.
A number of systems are commonly known for applying the flag force. One such flag driving system is a non-controllable dead weight system. This system uses potential energy derived from a constant weight that is attached to the flag by a cord or some other flexible connector to create a tension on the cord, and therefore, a force on the flag. The net result is a force transmitting from the flag onto the document stack.
A drawback of this non-controllable dead weight system is that it is not able to maximize the performance of the document handling device. Specifically, it is deficient in maintaining proper document spacing. The source of this deficiency relates to the force exerted by the flag on the document stack. For example, pushing a stack of several thousand documents requires far more force than pushing the last few documents. In this system, however, the force exerted by the flag on the document stack does not vary according to the number of documents in the stack. This inability to adequately control the force exerted on the document stack results in inconsistent spacing, thereby causing the performance of the document handling device to suffer.
A variation of the dead weight system, herein referred to as the variable dead weight system, attempts to improve the non-controllable dead weight system to maximize the performance of the document handling device. The variable dead weight system attempts to adjust the flag force by using a variable dead weight, such as a chain that falls onto a supporting surface during flag travel, attached to the flag. As the document stack is reduced and the flag moves accordingly, the chain falls onto the supporting surface, thereby reducing the flag force. Although this system can better match the flag force to the force required to move the document stack, it is still not responsive to the actual force requirements that may vary due to conditions in the document stack.
Another method of producing flag force against a document stack is to use some sort of motor arrangement. To best adapt to flag force requirements, many motor driven flag systems often use sensors to measure and adjust the flag motion and force. However, because the mechanical environment created by a feed sorter can be violent, the sensors must undergo filtering to ensure that the sensed values are accurate. Although these systems are more responsive to flag force requirements, they are complex, costly and are subject to maintenance issues. It is desirable to provide an improved mechanism that produces a flag force that is responsive to the force needed to move the document stack.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an apparatus for driving a flag element capable of presenting an adjustable force for moving a document stack.
A further object of the present invention is to provide an arrangement for adaptively driving the flag element of a document handling device that is durable, reliable, and economical to produce.
Accordingly, the present invention is directed to an arrangement for adaptively driving the flag element of a document handling device, such as a document sorter. The invention uses a force generating mechanism to produce a torque on the periphery of a cam. A flexible connector that wraps around the cam is used to pull the flag element. The cam is shaped such that the force exerted on the flag element produced by constant torque varies in accordance with the size of the document stack in the hopper of the document handling device.
BRIEF DESCRIPTION OF THE DRAWINGS
Additional objects, features, and advantages of the present invention will become apparent from studying the following detailed description and claims when taken in conjunction with the accompanying drawing, in which:
FIG. 1 is a perspective view of an arrangement for adaptively driving the flag element of a document handling device according to the principles of the present invention; and
FIG. 2 is a perspective view of an alternative driving means for rotatably driving a cam of the arrangement of FIG. 1 .
DETAILED DESCRIPTION
The drawing shows merely exemplary embodiments of the present invention for purposes of illustration only, one skilled in the art will readily recognize that the principles of the invention are well adapted for application to devices other than document handling devices as well as to document handling devices other than the one shown in the drawing. Furthermore, one skilled in the art will readily appreciate that various adaptations of the preferred embodiment may be combined or otherwise modified without departing from the scope of the invention.
A document handling apparatus 100 is illustrated in FIG. 1 . As shown, the document handling apparatus 100 includes a hopper 104 which contains a document stack 106 . The hopper 104 has a floor 104 a and a leading edge guide wall 104 b that serve to support the documents in the document stack 106 . Leading edge guide wall 104 b also provides support for a flag element 102 . Flag element 102 abuts the document stack 106 and, during feeding, is used to move the document stack 106 across the hopper floor 104 a toward feeding elements 108 . Feeding elements 108 include mechanisms commonly known in the art, such as a nip, nudger, and feed wheel. Documents are then individually removed from the hopper 104 by feeding elements 108 and are introduced into a document transport (not shown) for processing and sorting.
The flag element 102 is associated with a cam 114 by a flag drive string 110 , as seen in the preferred embodiment of FIG. 1, or by some other suitable flexible connector, such as a cable or chain. The flag drive string attaches to the flag element 102 and is guided by pulley 118 a and pulley 118 b , which are attached along the leading edge guide wall 104 b . An additional pulley 118 c guides the flag drive string 110 to its attachment at cam 116 . FIG. 1 shows a preferred embodiment in which the flag drive string 110 attaches to a constant weight 112 . Alternatively, the constant weight 112 may be excluded from the system.
The cam 114 is shaped such that its radius varies. As depicted in FIG. 1, cam 114 has a minimum radial distance 114 b and gradually increases to a maximum radial distance 114 a . The cam 114 is rotatively supported by shaft 116 . In the preferred embodiment of FIG. 1, the shaft 116 connected to an electric motor 120 is shown as a method of producing a torque on the cam. Alternatively, other known force generating mechanisms may be used to create a torque on the cam 114 , such as a dead weight 115 suspended from a cable.
During operation, electric motor 120 produces a constant torque. Shaft 116 acts to transfer the torque developed by the electric motor 120 to the cam 114 , causing it to rotate. The rotation of the cam 114 exerts a tension on the flag drive string 110 and subsequently on the flag element 102 . Accordingly, the flag element 102 then exerts a force at the back end of the document stack 106 . The flag drive string 110 prevents free motor rotation.
The cam 114 takes advantage of the known relationship between the flag element 102 position and the flag drive string 110 position. The cam 114 is shaped such that the force of the flag element 102 produced by a constant motor torque varies to suit the size of the document stack 106 in the hopper 104 . For example, if the document stack is large, a large flag force is required; since the motor torque is constant, the radial length of the cam is small. As the size of the document stack decreases, the force required to move the document stack decreases; since the motor torque is constant, the radial length of the cam must increase.
As stated above, in the preferred embodiment of FIG. 1, a constant weight 112 is interconnected between the flag element 102 and the cam 114 . The constant weight 112 is supplemental to the motor 120 to reduce the requirement on the motor 120 , thereby reducing wear and increasing its service life. In addition, should the motor 120 fail, the constant weight 112 could allow the document handling device 100 to continue to function at a reduced performance level.
The arrangement of the present invention allows the cam to take advantage of the known relationship between the flag element position and the flag drive string position in order to match the flag element force needed to move the document stack. Because the arrangement is capable of adjusting flag force requirements without the use of sensors, it is economical to produce and minimizes system complexity issues.
In addition, if an electric motor is used with the cam, additional adjustments can be made to increase the performance of the document handling device. For example, the current supplied to the motor could be altered to accommodate document handling devices of different speeds. Since document handling devices use a variety of speed selections to perform simple, high volume document processing or complex, low volume document processing, the electric current could be adjusted to match the speed requirement of the particular document processing operation. In addition, since the feeding elements of document handling devices are subject to wear, the motor could be adjusted to work in harmony with the performance of the worn feeding elements.
A variation of the present invention would be to include sensors with the present invention to further optimize the performance of the document handling device.
The foregoing discussion and drawing discloses and describes merely an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion that various changes, modifications and variations may be made therein without departing from the scope of the invention as defined in the following claims. | An arrangement for adaptively driving the flag element of a document handling device, such as a document sorter. The invention uses a force generating mechanism to produce torque at the periphery of a cam. A flexible connector that is wrapped around the cam is used to pull the flag element. The cam is shaped such that the force exerted on the flag element produced by constant torque varies in accordance with the size of the document stack in the hopper of the document handling device. | 1 |
TECHNICAL FIELD
[0001] The present invention relates generally to the field of actuator systems, and more particularly to an electromechanical redundant actuator.
BACKGROUND ART
[0002] Redundant actuator systems are generally known. These systems typically arrange multiple actuators in a way in which their displacement is summed, or their torque is summed.
BRIEF SUMMARY OF THE INVENTION
[0003] With parenthetical reference to the corresponding parts, portions or surfaces of the disclosed embodiment, merely for the purposes of illustration and not by way of limitation, the present invention provides an actuator system ( 100 , 200 ) comprising: a controlled element ( 180 , 280 ) configured for rotary movement about a first axis ( 105 , 203 ) relative to a reference structure ( 110 , 210 ); a linkage system ( 170 , 270 ) connected to the element and the reference structure; a first actuator ( 120 , 220 ) configured and arranged to power a first degree of freedom of the linkage system ( 123 relative to 122 , 223 relative to 222 ); a second actuator ( 140 , 240 ) configured and arranged to power a second degree of freedom of the linkage system ( 143 relative to 142 , 243 relative to 242 ), the first degree of freedom and the second degree of freedom being independent degrees of freedom; the linkage system having a first link ( 123 , 223 ) configured for rotary movement about a second axis ( 104 , 204 ) relative to the reference structure; the first axis and the second axis not being coincident; the linkage system having a second link ( 143 , 243 ) configured for rotary movement about a third axis ( 105 , 205 ) relative to the reference structure; the first link and the second link coupled ( 160 , 260 ) such that rotation of the first link about the second axis in a first direction ( 126 , 146 , 226 , 246 ) causes rotation of the second link about the third axis in a second direction ( 126 , 146 , 226 , 246 ); the linkage system configured and arranged such that a first angle of rotation ( 144 , 244 ) between the element and the reference structure may be driven independently of a second angle of rotation ( 125 , 225 ) between the first link and the reference structure; wherein one of the first or second actuators is configured and arranged to drive rotation of the element about the first axis when the other of the first or second actuator is operatively locked
[0004] The first axis ( 105 , 203 ) and the second axis ( 104 , 204 ) may be substantially parallel and operatively offset a substantially constant distance. The first axis ( 203 ), the second axis ( 204 ) and the third axis ( 205 ) may be substantially parallel and operatively offset a substantially constant distance. The third axis may be substantially coincident with the second axis ( 104 ). The first link and the second link may be coupled with a coupling comprising a connecting link ( 160 ) having a first pivot ( 160 b ) and a second pivot ( 160 c ). The coupling may comprise a bar link ( 160 a ) between the first pivot and the second pivot. The first link and the second link may be coupled with a coupling comprising meshed gears. The first link and the second link may be coupled ( 160 , 260 ) such that the first direction of rotation ( 126 , 226 ) of the first link is opposite to the second direction of rotation ( 146 , 246 ) of the second link. The first link and the second link may be coupled ( 260 ′) such that the first direction of rotation ( 226 ′) of the first link is the same as the second direction of rotation ( 226 ′) of the second link. The actuator system may further comprise: a third actuator ( 320 ) configured and arranged to power a third degree of freedom of the linkage system ( 323 relative to 322 ); a fourth actuator ( 340 ) configured and arranged to power a fourth degree of freedom of the linkage system ( 343 relative to 342 ), the third degree of freedom and the fourth degree of freedom being independent degrees of freedom; the linkage system having a third link ( 323 ) configured for rotary movement about a fourth axis ( 304 ) relative to the reference structure; the linkage system having a fourth link ( 343 ) configured for rotary movement about a fifth axis ( 305 ) relative to the reference structure; the fourth axis and the fifth axis not being coincident with each other or with the first axis or the second axis; the third link and the fourth link coupled ( 360 ) such that rotation of the third link about the fourth axis in a first direction causes rotation of the fourth link about the fifth axis in a second direction; wherein one of the third or fourth actuators is configured and arranged to drive rotation of the element about the first axis when the other of the third or fourth actuator is operatively locked. The first, second, third or fourth actuators may be configured and arranged to drive rotation of the element about the first axis when the others of the first, second, third and fourth actuators have failed open. The third link and the fourth link may be coupled ( 360 ) such that the first direction of rotation of the third link is opposite to the second direction of rotation of the fourth link. The third link and the fourth link may be coupled ( 260 ′) such that the first direction of rotation of the third link is the same as the second direction of rotation of the fourth link. Each of the actuators may be supported by a bearing ( 436 ). The first actuator may comprise a planetary gear stage ( 600 ). The linkage system may comprise at least five links. The linkage system may comprise a plurality of pivot joints between the links. The first actuator may comprise a rotary actuator. The first actuator may comprise a rotary motor, a hydraulic actuator, or an electric motor. The first link may comprise a stator and the second link may comprise a stator. Each of the actuators may comprise a brake. The actuator system may further comprise a brake ( 603 ) configured and arranged to hold one of the degrees of freedom of the linkage system constant. The actuator system may further comprise a spring ( 604 ) configured and arranged to bias one of the degrees of freedom of the linkage system. The spring may be selected from a group consisting of a torsional spring, a linear spring, and a flexure. The actuator system may further comprise a damper ( 605 ) configured and arranged to dampen rotation of at least one link in the linkage system. The damper may be selected from a group consisting of a linear damper and a rotary damper. The first actuator and the second actuator may comprise a stepper motor or a permanent magnet motor. The first actuator and the second actuator may comprise a magnetic clutch ( 607 ). The element may be selected from a group consisting of a shaft and an aircraft control surface. The element may be selected from a group consisting of a wing spoiler, a flap, a flaperon and an aileron. The reference structure may be selected from a group consisting of an actuator frame, an actuator housing and an airframe.
[0005] In another aspect, an actuator system ( 100 ′, 200 ′) is provided comprising: a controlled element ( 180 , 280 ) configured for rotary movement about a first axis ( 105 , 203 ) relative to a reference structure ( 110 , 210 ); a linkage system ( 170 , 270 ) connected to the element and the reference structure; a first actuator ( 120 , 220 ) configured and arranged to power a first degree of freedom of the linkage system ( 123 relative to 122 , 223 relative to 222 ); a hold device ( 140 ′, 240 ′) configured and arranged to selectively lock a second degree of freedom of the linkage system ( 143 ′ relative to 142 ′, 243 ′ relative to 242 ′), the first degree of freedom and the second degree of freedom being independent degrees of freedom; the linkage system having a first link ( 123 , 223 ) configured for rotary movement about a second axis ( 104 , 204 ) relative to the reference structure; the first axis and the second axis not being coincident; the linkage system having a second link ( 143 ′, 243 ′) configured for rotary movement about a third axis ( 105 , 205 ) relative to the reference structure; the first link and the second link coupled ( 160 , 260 ) such that rotation of the first link about the second axis in a first direction ( 126 , 146 , 226 , 246 ) causes rotation of the second link about the third axis in a second direction ( 126 , 146 , 226 , 246 ); the linkage system configured and arranged such that a first angle of rotation ( 144 , 244 ) between the element and the reference structure may be driven independently of a second angle of rotation ( 125 , 225 ) between the first link and the reference structure; wherein the hold device is configured and arranged to lock the second degree of freedom when the first actuator is operational and to unlock the second degree of freedom when the first actuator is operatively locked.
[0006] The first axis ( 105 , 203 ) and the second axis ( 104 , 204 ) may be substantially parallel and operatively offset a substantially constant distance. The first axis ( 203 ), the second axis ( 204 ) and the third axis ( 205 ) may be substantially parallel and operatively offset a substantially constant distance. The third axis may be substantially coincident with the second axis ( 104 ). The first link and the second link may be coupled ( 160 , 260 ) such that the first direction of rotation ( 126 , 226 ) of the first link is opposite to the second direction of rotation ( 146 , 246 ) of the second link. The first link and the second link may be coupled ( 260 ′) such that the first direction of rotation ( 226 ′) of the first link is the same as the second direction of rotation ( 226 ′) of the second link. The actuator system may further comprising: a second actuator ( 320 ) configured and arranged to power a third degree of freedom of the linkage system ( 323 relative to 322 ); a second hold device ( 340 ′) configured and arranged to selectively lock a fourth degree of freedom of the linkage system ( 343 ′ relative to 342 ′), the third degree of freedom and the fourth degree of freedom being independent degrees of freedom; the linkage system having a third link ( 323 ) configured for rotary movement about a fourth axis ( 304 ) relative to the reference structure; the linkage system having a fourth link ( 343 ′) configured for rotary movement about a fifth axis ( 305 ) relative to the reference structure; the fourth axis and the fifth axis not being coincident with each other or with the first axis or the second axis; the third link and the fourth link coupled ( 360 ) such that rotation of the third link about the fourth axis in a first direction causes rotation of the fourth link about the fifth axis in a second direction; wherein the second hold device is configured and arranged to lock the fourth degree of freedom when the second actuator is operational and to unlock the fourth degree of freedom when the second actuator is operatively locked. The first actuator may comprise a rotary actuator. The first link may comprise a stator. The element may be selected from a group consisting of a shaft and an aircraft control surface. The reference structure may be selected from a group consisting of an actuator frame, an actuator housing and an airframe.
[0007] In another aspect, an actuator system ( 100 , 200 ) is provided comprising: a controlled element ( 180 , 280 ) configured for rotary movement about a first axis ( 105 , 203 ) relative to a reference structure ( 110 , 210 ); a plurality of actuator units, each of the actuator units comprising: a linkage system ( 170 , 270 ) connected to the element and the reference structure; a first actuator ( 120 , 220 ) configured and arranged to power a first degree of freedom of the linkage system ( 123 relative to 122 , 223 relative to 222 ); a second actuator ( 140 , 240 ) configured and arranged to power a second degree of freedom of the linkage system ( 143 relative to 142 , 243 relative to 242 ), the first degree of freedom and the second degree of freedom being independent degrees of freedom; the linkage system having a first link ( 123 , 223 ) configured for rotary movement about a second axis ( 104 , 204 ) relative to the reference structure; the first axis and the second axis not being coincident; the linkage system having a second link ( 143 , 243 ) configured for rotary movement about a third axis ( 105 , 205 ) relative to the reference structure; the first link and the second link coupled ( 160 , 260 ) such that rotation of the first link about the second axis in a first direction ( 126 , 146 , 226 , 246 ) causes rotation of the second link about the third axis in a second direction ( 126 , 146 , 226 , 246 ); the linkage system configured and arranged such that a first angle of rotation ( 144 , 244 ) between the element and the reference structure may be driven independently of a second angle of rotation ( 125 , 225 ) between the first link and the reference structure; wherein one of the first or second actuators is configured and arranged to drive rotation of the element about the first axis when the other of the first or second actuator is operatively locked.
[0008] In another aspect, an actuator system ( 100 , 200 ) is provided comprising: a controlled element ( 180 , 280 ) configured for rotary movement about a first axis ( 105 , 203 ) relative to a reference structure ( 110 , 210 ); a plurality of actuator units, each of the actuator units comprising: a first actuator ( 120 , 220 ) configured and arranged to power a first degree of freedom of the linkage system ( 123 relative to 122 , 223 relative to 222 ); a hold device ( 140 ′, 240 ′) configured and arranged to selectively lock a second degree of freedom of the linkage system ( 143 ′ relative to 142 ′, 243 ′ relative to 242 ′), the first degree of freedom and the second degree of freedom being independent degrees of freedom; the linkage system having a first link ( 123 , 223 ) configured for rotary movement about a second axis ( 104 , 204 ) relative to the reference structure; the first axis and the second axis not being coincident; the linkage system having a second link ( 143 ′, 243 ′) configured for rotary movement about a third axis ( 105 , 205 ) relative to the reference structure; the first link and the second link coupled ( 160 , 260 ) such that rotation of the first link about the second axis in a first direction ( 126 , 146 , 226 , 246 ) causes rotation of the second link about the third axis in a second direction ( 126 , 146 , 226 , 246 ); the linkage system configured and arranged such that a first angle of rotation ( 144 , 244 ) between the element and the reference structure may be driven independently of a second angle of rotation ( 125 , 225 ) between the first link and the reference structure; wherein the hold device is configured and arranged to lock the second degree of freedom when the first actuator is operational and to unlock the second degree of freedom when the first actuator is operatively locked.
[0009] In another aspect, an actuator system is provided comprising: a reference structure; an output member rotatably coupled to the reference structure for rotation about a first axis; a first actuator having a first member and a second member, the second member configured to rotate relative to the reference structure, the first member configured to rotate relative to the reference structure about a second axis, the first member configured to rotate relative to the reference structure independent of the rotation of the second member relative to the reference structure; a second actuator having a first member and a second member, the second member configured to rotate relative to the reference structure, the first member configured to rotate relative to the reference structure about a third axis, the first member configured to rotate relative to the reference structure independent of the rotation of the second member relative to the reference structure; a first link pivotally connected between the first member of the first actuator and the first member of the second actuator, the first member of the first actuator and the first member of the second actuator coupled such that rotation of the first member of the first actuator in a first direction causes rotation of the first member of the second actuator in a second direction; a second link pivotally connected between the second member of the first actuator and the output member.
[0010] The actuator system may further comprise a third link pivotally connected between the second member of the second actuator and the output member. The first direction and the second direction may be the same. The first direction and the second direction may be opposite. The first axis and the third axis may be coincident. The first member may be a stator. The second member may be a rotor.
[0011] In another aspect, an actuator system is provided comprising: a reference structure; an output member rotatably coupled to the reference structure for rotation about a first axis; a first actuator having a first member and a second member, the second member configured to rotate relative to the reference structure, the first member configured to rotate relative to the reference structure about a second axis, the first member configured to rotate relative to the reference structure independent of the rotation of the second member relative to the reference structure; a holding device having a first member and a second member, the second member configured to rotate relative to the reference structure, the holding device configured to alternate between a first configuration where the rotational position of the first member relative to the second member is locked and a second position where the first and second members are free to rotate relative to each other; a first link pivotally connected between the first member of the first actuator and the first member of the holding device, the first member of the first actuator and the first member of the holding device coupled such that rotation of the first member of the first actuator in a first direction causes rotation of the first member of the holding device in a second direction; a second link pivotally connected between the second member of the first actuator and the output member; wherein the holding device moves from the first configuration to the second configuration when the first actuator is operatively locked.
[0012] The actuator system may further comprise a third link pivotally connected between the second member of the holding device and the output member. The holding device may be a magnetic clutch. The first direction and the second direction may be the same. The first direction and the second direction may be opposite. The first axis and the third axis may be coincident. The first member may be a stator. The second member may be a rotor.
[0013] In another aspect, a method of controlling an actuator system is provided comprising the steps of: providing an actuator system comprising: a controlled element configured for rotary movement about a first axis relative to a reference structure; a linkage system connected to the element and the reference structure; a first actuator configured and arranged to power a first degree of freedom of the linkage system; a second actuator configured and arranged to power a second degree of freedom of the linkage system, the first degree of freedom and the second degree of freedom being independent degrees of freedom; the linkage system having a first link configured for rotary movement about a second axis relative to the reference structure; the first axis and the second axis not being coincident; the linkage system having a second link configured for rotary movement about a third axis relative to the reference structure; the first link and the second link coupled such that rotation of the first link about the second axis in a first direction causes rotation of the second link about the third axis in a second direction; the linkage system configured and arranged such that a first angle of rotation between the element and the reference structure may be driven independently of a second angle of rotation between the first link and the reference structure; wherein one of the first or second actuators is configured and arranged to drive rotation of the element about the first axis when the other of the first or second actuator is operatively locked; and providing power to the first actuator and the second actuator simultaneously such that the controlled element is rotated about the second axis and an angular position of the first link is held constant about the first axis.
[0014] In another aspect, a method of controlling an actuator system is provided comprising the steps of: providing an actuator system comprising: a controlled element configured for rotary movement about a first axis relative to a reference structure; a linkage system connected to the element and the reference structure; a first actuator configured and arranged to power a first degree of freedom of the linkage system; a hold device configured and arranged to selectively lock a second degree of freedom of the linkage system, the first degree of freedom and the second degree of freedom being independent degrees of freedom; the linkage system having a first link configured for rotary movement about a second axis relative to the reference structure; the first axis and the second axis not being coincident; the linkage system having a second link configured for rotary movement about a third axis relative to the reference structure; the first link and the second link coupled such that rotation of the first link about the second axis in a first direction causes rotation of the second link about the third axis in a second direction; the linkage system configured and arranged such that a first angle of rotation between the element and the reference structure may be driven independently of a second angle of rotation between the first link and the reference structure; wherein the hold device is configured and arranged to lock the second degree of freedom when the first actuator is operational and to unlock the second degree of freedom when the first actuator is operatively locked; and providing power to the first actuator and the hold device simultaneously such that the hold device link locks the second degree of freedom of the linkage system, and the first actuator applies a desired torque to the controlled element
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is an isometric view of a first actuator system.
[0016] FIG. 2 is an isometric view of an alternate embodiment of the first actuator system.
[0017] FIG. 3 is a perspective view of a second actuator system.
[0018] FIG. 4 is a perspective view of an alternate embodiment of the second actuator system.
[0019] FIG. 5 is a perspective view of a third actuator system.
[0020] FIG. 6 is an alternate embodiment of the third actuator system.
[0021] FIG. 7 is an alternate embodiment of the second actuator system.
[0022] FIG. 8 is a front perspective view of a fourth actuator system.
[0023] FIG. 9 is a rear perspective view of the fourth actuator system.
[0024] FIG. 10 is a front elevational view of the fourth actuator system.
[0025] FIG. 11 is a side elevational view of the fourth actuator system.
[0026] FIG. 12 is a sectional view taken along lines 12 - 12 of FIG. 11 .
[0027] FIG. 13 is a rear elevational view of the fourth actuator system.
[0028] FIG. 14 is a partially exploded front perspective view of the fourth actuator system.
[0029] FIG. 15 is a partially exploded rear perspective view of the fourth actuator system.
[0030] FIG. 16 is a front perspective view of the fourth actuator system with a reference structure removed for clarity.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] At the outset, it should be clearly understood that like reference numerals are intended to identify the same structural elements, portions or surfaces consistently throughout the several drawing figures, as such elements, portions or surfaces may be further described or explained by the entire written specification, of which this detailed description is an integral part. Unless otherwise indicated, the drawings are intended to be read (e.g., cross-hatching, arrangement of parts, proportion, debris, etc.) together with the specification, and are to be considered a portion of the entire written description of this invention. As used in the following description, the terms “horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well as adjectival and adverbial derivatives thereof, (e.g., “horizontally”, “rightwardly”, “upwardly”, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or of rotation, as appropriate.
[0032] Referring now to the drawings, and initially to FIG. 1 thereof, this invention provides an improved actuator system, of which a first embodiment is generally indicated at 100 . Reference structure 110 may comprise a rigid material. Reference structure 110 has a first portion 110 A and a second portion 110 B, which are rigidly connected to each other through a third portion 110 C. First portion 110 A holds two couplings 112 and 113 , which are connected to shaft 121 and shaft 141 respectively. Coupling 112 holds shaft 121 in rotary engagement for rotation relative to reference structure 110 about axis 104 . Similarly, coupling 113 holds shaft 141 in rotary engagement for rotation relative to reference structure 110 about axis 105 . Axes 104 and 105 are generally parallel to each other and separated by a fixed distance.
[0033] First rotary actuator 120 has a first member 123 and a second member 122 which are configured and arranged for relative rotary motion to each other about axis 104 . Rotary actuator 120 is an electric motor, however other actuator types such as, but not limited to, hydraulic actuators, pneumatic actuators, or other similar actuators may also be used. First member 123 may be referred to as a stator and second member 122 may be referred to as a rotor, however, it should be noted that neither stator 123 nor rotor 122 are stationary relative to reference structure 110 .
[0034] Rotor 122 is rigidly coupled to shaft 121 . Stator 123 is specifically not rigidly mounted to reference structure 110 . More concretely, stator 123 is able to rotate relative to reference structure 110 about axis 104 independent of the rotation of rotor 122 relative to reference structure 110 . Stated another way, first rotary actuator 120 has two degrees of freedom relative to reference structure 110 . A first degree of freedom can be defined as angle of rotation 124 of rotor 122 relative to reference structure 110 . A second degree of freedom can be defined as angle of rotation 125 of stator 123 relative to reference structure 110 .
[0035] Second rotary actuator member 140 has first member 143 and second member 142 which are configured and arranged for relative rotary motion to each other about axis 105 . Rotary actuator 140 is an electric motor, however other actuator types such as, but not limited to hydraulic actuators, pneumatic actuators, or other similar actuators may also be used. First member 143 may be referred to as a stator and second member 142 may be referred to as a rotor. However, it should be noted that neither stator 143 nor rotor 142 are stationary relative to reference structure 110 .
[0036] Rotor 142 is rigidly coupled to shaft 141 . Stator 143 is specifically not rigidly mounted to reference structure 110 . More concretely, stator 143 is able to rotate relative to reference structure 110 about axis 105 independent the rotation of rotor 142 relative to the reference structure 110 . Stated another way, second actuator 140 has two degrees of freedom relative to reference structure 110 . A first degree of freedom can be defined as angle of rotation 144 of rotor 142 relative to reference structure 110 . A second degree of freedom can be defined as angle of rotation 145 of stator 123 relative to reference structure 110 .
[0037] Output member 180 is rigidly coupled to rotor 142 . Therefore, output member rotates together with rotor 142 relative to reference structure 110 about axis 105 . Second portion 110 B of reference structure 110 has couplings 115 and 116 which respectively provide additional support in holding output member 180 and rotor 122 in rotary engagement with reference structure 110 . Output member 180 may be coupled to an object to be driven, such as an aircraft control surface.
[0038] Stator 123 and stator 143 are rotationally coupled together through coupling 160 . Coupling 160 causes stator 123 to rotate relative to reference structure 110 by an angle opposite to the rotation of stator 143 relative to reference structure 110 . More specifically, coupling 160 causes any change in angle 125 to cause an equal and opposite change in angle 145 . In other words, a degree of freedom between rotary actuator 120 and reference structure 110 is caused to be shared with one degree of freedom between rotary actuator 140 and reference structure 110 by coupling 160 . Coupling 160 is a link pivotally connected to stator 123 and pivotally connected to stator 143 . Drive arm portion 123 a is disposed on stator 123 , and drive arm portion 143 a is disposed on stator 143 . Link 160 a is pivotally connected between drive arm portions 123 a and 143 a . However, coupling 160 my alternatively be a gear coupling, a belt coupling, or other similar coupling.
[0039] Rotor 122 and rotor 142 are also coupled together through coupling 190 . Coupling 190 causes rotor 122 to rotate relative to reference structure 110 by an angular direction equal to how rotor 142 rotates relative to reference structure 110 . More specifically, coupling 190 causes any change in angle 124 to equal a change in angle 144 . In other words, a degree of freedom between rotary actuator 120 and reference structure 110 is caused to be shared with one degree of freedom between rotary actuator 140 and reference structure 110 by coupling 190 . As shown in FIG. 1 , coupling 190 is a link 190 a pivotally connected to drive arm portion 122 A of member 122 and pivotally connected to drive arm portion 142 A of member 142 , however, coupling 190 my alternatively be a gear coupling, a belt coupling, or other similar coupling.
[0040] While coupling 160 causes stator 123 and stator 143 to rotate in opposite directions relative to reference structure 110 , coupling 190 causes rotor 122 and rotor 142 to rotate in equivalent directions relative to reference structure 110 .
[0041] Linkage 170 is a set of rigid links and joints between reference member 110 and output member 180 . More specifically, linkage 170 comprises couplings 160 and 190 , and members 121 , 122 , 123 , 141 , 142 , and 143 . Linkage 170 has two degrees of freedom relative to reference 110 . In other words, the state of linkage 170 relative to reference 110 can be described by two independent variables. For example, knowing angle 144 (which represents the angle of rotor 142 to reference structure 110 ) and angle 124 (the angle of shaft 121 relative to reference structure 110 ) specifically define the state of linkage 170 since no member (link) within linkage 170 can be moved without adjusting angles 144 or 124 . In this view, angle 124 and angle 144 represent two independent degrees of freedom of linkage 170 . Alternatively, the two degrees of freedom of linkage 170 can be defined as angle 125 and angle 144 . No linkage 170 member can be moved relative to linkage 110 without changing angle 125 or angle 144 .
[0042] Rotary actuator 100 is generally operated by powering first actuator 120 and second actuator 140 together at the same time to cause output member 180 to move relative to reference structure 110 in a desired manner. For example, if a user desires to cause output member 180 to rotate clockwise relative to reference structure 110 , in other words, if angle 144 is to be decreased, actuator 120 and actuator 140 would be actuated at the same time, actuator 120 providing a torque of equal and opposite magnitude as actuator 140 . More specifically, actuator 120 is actuated so as to apply a torque urging rotor 122 to rotate clockwise relative to stator 123 . At the same time, actuator 140 is actuated so as to apply a torque urging rotor 142 to rotate clockwise relative to stator 143 . Under this scenario, counteracting torques from actuator 120 and actuator 140 act against each other through coupling 160 . When actuator 120 applies a torque to rotor 122 in the clockwise direction, an equal and opposite torque is applied to coupling 160 , urging coupling 160 to rotate counterclockwise. The torque applied by actuator 120 onto coupling 160 manifests as a downward rightwards force on coupling 160 . When actuator 140 applies a torque to rotor 142 in the clockwise direction, an equal and opposite torque is applied to coupling 160 . The torque applied by actuator 140 onto coupling 160 manifests as an upwards-leftwards force applied on coupling 160 by actuator 140 . The force applied by actuator 120 onto coupling 160 is generally equal and opposite the force applied by actuator 140 onto coupling 160 . This generally results in stators 123 and 143 remaining stationary while rotors 122 and 142 rotate clockwise. Coupling 190 causes the angles of rotation 124 , 144 of rotors 122 and 142 relative to reference structure 110 to remain equivalent.
[0043] In order to cause output member 180 to rotate counter clockwise relative to reference structure 110 , rotary actuators 120 and 140 are actuated in the reverse direction compared to when causing output member 180 to rotate clockwise.
[0044] Actuator 100 has the advantageous characteristic that if either actuator 120 or actuator 140 lock up (such as an electromechanical jam, or hydraulic valve lock), output member 180 will continue to be actuated in the desired direction of rotation by the non-failing actuator. This is because the locked up actuator will still be able to provide a counteracting torque to the other actuator through coupling 160 . For example, consider a user desiring to rotate output member 180 clockwise relative to reference structure 110 (decreasing angle 144 ) when actuator 120 inadvertently rotationally locks stator 123 relative to rotor 122 . Because stator 123 is rotationally locked to rotor 122 , any change in angle 124 between rotor 122 and reference structure 110 will necessary equal any change in angle 125 between stator 123 and reference structure 110 . Note that stator 123 and rotor 122 may still rotate together as a unit relative to reference structure 110 . When actuator 140 applies a clockwise torque to rotor 142 , the equal and opposite torque on stator 143 is distributed through coupling 160 as an upwards and leftwards force on coupling 160 . This upwards and leftwards force on coupling 160 results in a clockwise torque applied to stator 123 which is transmitted through the locked up actuator as a clockwise torque onto rotor 122 . Coupling 190 causes the rotation of rotors 122 and 142 to be equalized, while output member 180 is rotated clockwise as desired through the jam.
[0045] In order to operate in a dual tandem mode, each actuator 120 , 140 is provided with a braking mechanism which may be internal or external and a controller. These brakes will allow the actuator system 100 to continue working if one of the actuators fails in an open state (e.g. an actuator loses power allowing the stator and rotor free rotation relative to each other). The brake is configured within each actuator to lock rotation between the actuators stator and rotor relative to each other. The brake may be a fail-safe brake which does not need power in order to brake. In this dual tandem configuration, when one of the actuators 120 , 140 fails in an open state, the brake in that failing actuator is engaged. This allows the remaining actuator 120 , 140 to still cause actuation of output member 180 . However, during such a failure the speed that output member 180 rotates relative to the working actuator will be half the speed that the output member 180 rotates at when both actuators are working.
[0046] Turning to FIG. 2 , which shows an alternate embodiment 100 ′, actuator 120 is paired with a holding device 140 ′ which includes, but is not limited to, a brake, a magnetic clutch, a toroid motor, or the like. Under normal operation, holding device 140 ′ locks the rotational position between member 143 ′ and member 142 ′. If the actuator 120 jams then the holding device 140 ′ releases the lock between member 143 ′ and member 142 ′ which effectively releases any effect actuator 120 has on output member 180 . This allows output member 180 to be driven by another actuator (not shown). This arrangement is a simplex configuration because it includes one actuator 120 and one holding device 140 ′ and if the actuator 120 fails, the unit drops out of the network as will be described in greater detail below. In yet another alternate simplex configuration, two actuators may be provided without any brakes on either actuator, where one actuator is configured to only hold its rotor and stator position, while the other actuator is used to drive output member 180 through linkage system 170 .
[0047] In FIG. 3 , a second actuator system is generally indicated at 200 . Reference structure 210 comprises a rigid material. Reference structure 210 has a first portion 210 A and a second portion 210 B, which are fixed. First portion 210 A holds two couplings 212 and 213 , which are connected to shaft 221 and shaft 241 respectively. Coupling 212 holds shaft 221 in rotary engagement for rotation relative to reference structure 210 about axis 204 . Similarly, coupling 213 holds shaft 241 in rotary engagement for rotation relative to reference structure 210 about axis 205 . Axes 204 and 205 are generally parallel to each other and separated by a fixed distance.
[0048] First rotary actuator 220 has a first member 223 and a second member 222 which are configured and arranged for relative rotary motion to each other about axis 204 . Rotary actuator 220 is an electric motor, however other actuator types such as, but not limited to, hydraulic actuators, pneumatic actuators, or other similar actuators may also be used. First member 223 may be referred to as a stator and second member 222 may be referred to as a rotor, however, it should be noted that neither stator 223 nor rotor 222 are stationary relative to reference structure 210 .
[0049] Rotor 222 is rigidly coupled to shaft 221 . Stator 223 is specifically not rigidly mounted to reference structure 210 . More concretely, stator 223 is able to rotate relative to reference structure 210 about axis 204 independent of the rotation of rotor 222 relative to reference structure 210 . Stated another way, first rotary actuator 220 has two degrees of freedom relative to reference structure 210 . A first degree of freedom can be defined as angle of rotation 224 of rotor 122 relative to reference structure 210 . A second degree of freedom can be defined as angle of rotation 225 of stator 223 relative to reference structure 210 .
[0050] Second rotary actuator member 240 has first member 243 and second member 242 which are configured and arranged for relative rotary motion to each other about axis 205 . Rotary actuator 240 is an electric motor, however other actuator types such as, but not limited to hydraulic actuators, pneumatic actuators, or other similar actuators may also be used. First member 243 may be referred to as a stator and second member 242 may be referred to as a rotor. However, it should be noted that neither stator 243 nor rotor 242 are stationary relative to reference structure 210 .
[0051] Rotor 242 is rigidly coupled to shaft 241 . Stator 243 is specifically not rigidly mounted to reference structure 210 . More concretely, stator 243 is able to rotate relative to reference structure 210 about axis 205 independent the rotation of rotor 242 relative to the reference structure 210 . Stated another way, second actuator 240 has two degrees of freedom relative to reference structure 210 . A first degree of freedom can be defined as angle of rotation 244 of rotor 242 relative to reference structure 210 . A second degree of freedom can be defined as angle of rotation 245 of stator 223 relative to reference structure 210 .
[0052] Output member 280 is coupled to rotors 222 , 242 . Therefore, output member 280 rotates together with rotors 222 , 242 relative to reference structure 210 . Second portion of 210 B reference structure 210 has couplings 215 and 216 which respectively provide additional support in holding rotors 222 , 242 in rotary engagement with reference structure 210 . Couplings 214 , 219 hold output member 280 in rotary engagement for rotation relative to reference structure 210 . Output member 280 may be coupled to an object to be driven, such as an aircraft control surface.
[0053] Stator 223 and stator 243 are rotationally coupled together through coupling 260 . Coupling 260 causes stator 223 to rotate relative to reference structure 210 by an angle opposite to the rotation of stator 243 relative to reference structure 210 . More specifically, coupling 260 causes any change in angle 225 to cause an equal and opposite change in angle 245 . In other words, a degree of freedom between rotary actuator 220 and reference structure 210 is caused to be shared with one degree of freedom between rotary actuator 240 and reference structure 210 by coupling 260 . Coupling 260 is a link 260 a pivotally connected to drive arm portion 223 a of stator 223 and pivotally connected to drive arm portion 243 a of stator 243 . However, coupling 260 may alternatively be a gear coupling, a belt coupling, or other similar coupling.
[0054] Rotor 222 and rotor 242 are both coupled to output member 280 through coupling 270 . Coupling 270 causes the rotation of both rotors 222 and 242 to be transmitted to the output member 280 such that the output member 280 rotates in the same direction as the rotors 222 , 242 relative to the reference structure 210 . More specifically, coupling 270 causes the rotation of the rotors 222 , 242 to be summed together at the output member 280 . Coupling 270 comprises a pair of links 270 a and 270 b . Link 270 a is pivotally connected between drive arm portion 222 A of member 222 and drive arm portion 280 a of output member 280 . Link 270 b is pivotally connected between drive arm portion 242 A of member 242 and drive arm portion 280 b of output member 280 . However, coupling 270 may alternatively be a gear coupling, a belt coupling, or other similar coupling.
[0055] While coupling 260 causes stator 223 and stator 243 to rotate in opposite directions relative to reference structure 210 , coupling 270 causes rotor 122 and rotor 142 to rotate in equivalent directions relative to reference structure 210 .
[0056] Linkage 290 is a set of rigid links and joints between reference member 210 and output member 280 . More specifically, linkage 290 comprises couplings 260 and 270 , and members 221 , 222 , 223 , 241 , 242 , and 243 . Linkage 290 has two degrees of freedom relative to reference 210 . In other words, the state of linkage 290 relative to reference 210 can be described by two independent variables. For example, knowing angle 244 (which represents the angle of rotor 242 to reference structure 210 ) and angle 224 (the angle of shaft 221 relative to reference structure 210 ) specifically define the state of linkage 290 since no member (link) within linkage 290 can be moved without adjusting angles 244 or 224 . In this view, angle 224 and angle 244 represent two independent degrees of freedom of linkage 290 . Alternatively, the two degrees of freedom of linkage 290 can be defined as angle 225 and angle 244 . No linkage 290 member can be moved relative to linkage 210 without changing angle 225 or angle 244 .
[0057] Rotary actuator 200 is generally operated by powering first actuator 220 and second actuator 240 together at the same time to cause output member 280 to move relative to reference structure 210 in a desired manner. For example, if a user desires to cause output member 280 to rotate clockwise relative to reference structure 210 (as shown in the apparatus orientation in FIG. 2 ), actuator 220 and actuator 240 would be actuated at the same time, actuator 220 providing a torque of equal and opposite magnitude as actuator 240 . More specifically, actuator 220 is actuated so as to apply a torque urging rotor 222 to rotate clockwise relative to stator 223 . At the same time, actuator 240 is actuated so as to apply a torque urging rotor 242 to rotate clockwise relative to stator 243 . Under this scenario, counteracting torques from actuator 220 and actuator 240 act against each other through coupling 260 . More specifically, when actuator 220 applies a torque to rotor 222 in the clockwise direction, an equal and opposite torque is applied to coupling 260 , urging coupling 260 to rotate counterclockwise. The torque applied by actuator 220 onto coupling 260 manifests as a downward rightwards force on coupling 260 . When actuator 240 applies a torque to rotor 242 in the clockwise direction, an equal and opposite torque is applied to coupling 260 . The torque applied by actuator 240 onto coupling 260 manifests as an upwards-leftwards force applied on coupling 260 by actuator 240 . The force applied by actuator 220 onto coupling 260 is generally equal and opposite the force applied by actuator 240 onto coupling 260 . This generally results in stators 223 and 243 remaining stationary while rotors 222 and 242 rotate clockwise. Coupling 270 causes the angles of rotation 224 , 244 of rotors 222 and 242 relative to reference structure 210 to remain equivalent.
[0058] In order to cause output member 280 to rotate counter clockwise relative to reference structure 210 , rotary actuators 220 and 240 are actuated in reverse compared to when causing output member 280 to rotate clockwise.
[0059] In order to operate in a dual tandem mode, each actuator 220 , 240 is provide with a brake that may be internal or external and a controller. If one of the actuators 220 , 240 loses power then the brake in the failing unit will be applied, allowing the remaining actuator 220 , 240 to move the output member at one half normal speed. Actuator 200 also has the advantageous characteristic that if either actuator 220 or actuator 240 lock up (such as an electromechanical jam, or hydraulic valve lock), output member 280 will continue to be actuated in the desired direction of rotation by the non-failing actuator. This is because the locked up actuator will still be able to provide a counteracting torque to the other actuator through coupling 260 . For example, consider a user desiring to rotate output member 280 clockwise relative to reference structure 210 when actuator 220 inadvertently rotationally locks stator 223 relative to rotor 222 . Because stator 223 is rotationally locked to rotor 222 , any change in angle 224 between rotor 222 and reference structure 210 will necessary equal any change in angle 225 between stator 223 and reference structure 210 . Note that stator 223 and rotor 222 may still rotate together as a unit relative to reference structure 210 . When actuator 240 applies a clockwise torque to rotor 242 , the equal and opposite torque on stator 243 is distributed through coupling 260 as an upwards and leftwards force on coupling 260 . This upwards and leftwards force on coupling 260 results in a clockwise torque applied to stator 223 which is transmitted through the locked up actuator as a clockwise torque onto rotor 2122 . Coupling 270 causes the rotation of rotors 222 and 242 to be equalized, while output member 280 is rotated clockwise as desired through the jam.
[0060] Turning to FIG. 4 , the actuator 220 is paired with holding device 240 ′ which includes, but is not limited to, a brake, a magnetic clutch, a toroid motor or the like. Under normal operation, holding device 240 ′ locks member 243 ′ and rotor 242 ′ relative to each other. If the actuator 220 jams or loses power then the holding device 240 ′ releases the rotor 242 ′ and the actuator 220 and hold device 240 ′ go into a bypass mode and rotate freely under the power of another actuator in the network. In yet another simplex configuration, actuators 220 and 240 of FIG. 3 may be provided without any brakes.
[0061] Turning to FIG. 5 , a system with dual tandem actuators 220 and 240 is paired with dual tandem actuators 320 and 340 to form a third actuator system generally indicated at 300 . Reference structure 310 comprises a rigid material. Reference structure 310 has a first portion 310 A and a second portion 310 B, which are fixed. First portion 310 A holds two couplings 312 and 313 , which are connected to shaft 321 and shaft 341 respectively. Coupling 312 holds shaft 321 in rotary engagement for rotation relative to reference structure 310 about axis 304 . Similarly, coupling 313 holds shaft 341 in rotary engagement for rotation relative to reference structure 310 about axis 305 . Axes 304 and 305 are generally parallel to each other and separated by a fixed distance.
[0062] First rotary actuator 320 has a first member 323 and a second member 322 which are configured and arranged for relative rotary motion to each other about axis 304 . Rotary actuator 320 is an electric motor, however other actuator types such as, but not limited to, hydraulic actuators, pneumatic actuators, or other similar actuators may also be used. First member 323 may be referred to as a stator and second member 322 may be referred to as a rotor, however, it should be noted that neither stator 323 nor rotor 322 are stationary relative to reference structure 310 .
[0063] Rotor 322 is rigidly coupled to shaft 321 . Stator 323 is specifically not rigidly mounted to reference structure 310 . More concretely, stator 323 is able to rotate relative to reference structure 310 about axis 304 independent of the rotation of rotor 322 relative to reference structure 310 . Stated another way, first rotary actuator 320 has two degrees of freedom relative to reference structure 310 . A first degree of freedom can be defined as angle of rotation 324 of rotor 322 relative to reference structure 310 . A second degree of freedom can be defined as angle of rotation 325 of stator 323 relative to reference structure 310 .
[0064] Second rotary actuator member 340 has first member 343 and second member 342 which are configured and arranged for relative rotary motion to each other about axis 305 . Rotary actuator 340 is an electric motor, however other actuator types such as, but not limited to hydraulic actuators, pneumatic actuators, or other similar actuators may also be used. First member 343 may be referred to as a stator and second member 342 may be referred to as a rotor. However, it should be noted that neither stator 343 nor rotor 342 are stationary relative to reference structure 310 .
[0065] Rotor 342 is rigidly coupled to shaft 341 . Stator 343 is specifically not rigidly mounted to reference structure 310 . More concretely, stator 343 is able to rotate relative to reference structure 310 about axis 305 independent the rotation of rotor 342 relative to the reference structure 310 . Stated another way, second actuator 340 has two degrees of freedom relative to reference structure 310 . A first degree of freedom can be defined as angle of rotation 344 of rotor 342 relative to reference structure 310 . A second degree of freedom can be defined as angle of rotation 345 of stator 323 relative to reference structure 310 .
[0066] Output member 280 is coupled to rotors 322 , 342 . Therefore, output member 280 rotates together with rotors 322 , 342 relative to reference structure 310 . Second portion of 310 B reference structure 310 has couplings 315 and 316 which respectively provide additional support in holding rotors 322 , 342 in rotary engagement with reference structure 310 . Output member 280 may be coupled to an object to be driven, such as an aircraft control surface.
[0067] Stator 323 and stator 343 are rotationally coupled together through coupling 360 . Coupling 360 causes stator 323 to rotate relative to reference structure 310 by an angle opposite to the rotation of stator 343 relative to reference structure 310 . More specifically, coupling 360 causes any change in angle 325 to cause an equal and opposite change in angle 345 . In other words, a degree of freedom between rotary actuator 320 and reference structure 310 is caused to be shared with one degree of freedom between rotary actuator 340 and reference structure 310 by coupling 360 . Coupling 360 is a link 360 a pivotally connected to drive arm portion 323 a of stator 323 and pivotally connected to drive arm portion 343 a of stator 343 . However, coupling 360 may alternatively be a gear coupling, a belt coupling, or other similar coupling.
[0068] Rotor 322 and rotor 342 are both coupled to output member 280 through coupling 370 . Coupling 370 causes the rotation of both rotors 322 and 342 to be transmitted to the output member 280 such that the output member 280 rotates in the same direction as the rotors 322 , 342 relative to the reference structure 310 . More specifically, coupling 370 causes the rotation of the rotors 322 , 342 to be summed together at the output member 280 . Coupling 370 comprises a pair of links 370 a and 370 b . Link 370 a is pivotally connected between drive arm portion 322 A of member 322 and drive arm portion 280 a of output member 280 . Link 370 b is pivotally connected between drive arm portion 342 a of member 342 and drive arm portion 280 b of output member 280 . However, coupling 370 may alternatively be a gear coupling, a belt coupling, or other similar coupling.
[0069] While coupling 360 causes stator 323 and stator 343 to rotate in opposite directions relative to reference structure 310 , coupling 370 causes rotor 322 and rotor 342 to rotate in equivalent directions relative to reference structure 310 .
[0070] Linkage 390 is a set of rigid links and joints between reference member 310 and output member 280 . More specifically, linkage 390 comprises couplings 360 and 370 , and members 321 , 322 , 323 , 341 , 342 , and 343 . Linkage 390 has two degrees of freedom relative to reference 310 . In other words, the state of linkage 390 relative to reference 310 can be described by two independent variables. For example, knowing angle 344 (which represents the angle of rotor 342 to reference structure 310 ) and angle 324 (the angle of shaft 321 relative to reference structure 310 ) specifically define the state of linkage 390 since no member (link) within linkage 390 can be moved without adjusting angles 344 or 324 . In this view, angle 324 and angle 344 represent two independent degrees of freedom of linkage 390 . Alternatively, the two degrees of freedom of linkage 390 can be defined as angle 325 and angle 344 . No linkage 390 member can be moved relative to linkage 310 without changing angle 325 or angle 344 .
[0071] Rotary actuator 300 is generally operated by powering first actuator 320 and second actuator 340 together at the same time to cause output member 380 to move relative to reference structure 310 in a desired manner. For example, if a user desires to cause output member 280 to rotate clockwise relative to reference structure 310 (as shown in the apparatus orientation in FIG. 5 ), actuator 320 and actuator 340 would be actuated at the same time, actuator 320 providing a torque of equal and opposite magnitude as actuator 340 . More specifically, actuator 320 is actuated so as to apply a torque urging rotor 322 to rotate clockwise relative to stator 323 . At the same time, actuator 340 is actuated so as to apply a torque urging rotor 342 to rotate clockwise relative to stator 343 . Under this scenario, counteracting torques from actuator 320 and actuator 340 act against each other through coupling 360 . More specifically, when actuator 320 applies a torque to rotor 322 in the clockwise direction, an equal and opposite torque is applied to coupling 360 , urging coupling 360 to rotate counterclockwise. The torque applied by actuator 320 onto coupling 360 manifests as a downward rightwards force on coupling 360 . When actuator 340 applies a torque to rotor 342 in the clockwise direction, an equal and opposite torque is applied to coupling 360 . The torque applied by actuator 340 onto coupling 360 manifests as an upwards-leftwards force applied on coupling 360 by actuator 340 . The force applied by actuator 320 onto coupling 360 is generally equal and opposite the force applied by actuator 340 onto coupling 360 . This generally results in stators 323 and 343 remaining stationary while rotors 322 and 342 rotate clockwise. Coupling 370 causes the angles of rotation 324 , 344 of rotors 322 and 342 relative to reference structure 310 to remain equivalent.
[0072] In order to cause output member 280 to rotate counter clockwise relative to reference structure 310 , rotary actuators 320 and 340 are actuated in reverse compared to when causing output member 280 to rotate clockwise.
[0073] In order to operate in a dual tandem mode, each actuator 220 , 240 , 320 , 340 is provided with a brake that may be internal or external and a controller. If one or more of the actuators 220 , 240 , 320 , 340 lose power then one of the remaining actuators 220 , 240 , 320 , 340 can move the output member 280 . The third actuator system 300 also has the advantageous characteristic that if any of the actuators 220 , 240 , 320 , 340 lock up (such as an electromechanical jam, or hydraulic valve lock), output member 280 will continue to be actuated in the desired direction of rotation by at least one of the non-failing actuators. This is because, in the case of failure of actuator 220 or 240 , the locked up actuator will still be able to provide a counteracting torque to the other actuator through coupling 260 . For example, consider a user desiring to rotate output member 280 clockwise relative to reference structure 210 when actuator 220 inadvertently rotationally locks stator 223 relative to rotor 222 . Because stator 223 is rotationally locked to rotor 222 , any change in angle 224 between rotor 222 and reference structure 210 will necessary equal any change in angle 225 between stator 223 and reference structure 210 . Note that stator 223 and rotor 222 may still rotate together as a unit relative to reference structure 210 . When actuator 240 applies a clockwise torque to rotor 242 , the equal and opposite torque on stator 243 is distributed through coupling 260 as an upwards and leftwards force on coupling 260 . This upwards and leftwards force on coupling 260 results in a clockwise torque applied to stator 223 which is transmitted through the locked up actuator as a clockwise torque onto rotor 2122 . Coupling 270 causes the rotation of rotors 222 and 242 to be equalized, while output member 280 is rotated clockwise as desired through the jam. Also, rotors 320 , 340 continue to rotate output member 280 in the clockwise direction.
[0074] Turning to FIG. 6 , each of the actuators 220 , 320 is paired with a holding device 240 ′ and 340 ′ for simplex unit operation as described above in connection with FIGS. 2 and 4 .
[0075] In FIG. 7 , coupling 260 ′ includes a link 260 a ′ that pivotally connects between drive arm portion 243 a of stator 243 and drive arm portion 223 a of stator 223 at pivot points 290 , 292 . In contrast to the arrangement of coupling 260 , the link 260 a ′ does not cross a line 261 ′ between the centers of axes 204 and 205 . The coupling 270 ′ includes a link 270 a ′ pivotally connected between drive arm portion 242 a and drive portion 280 a of output member 280 at pivot points 294 , 295 and a link 270 b ′ pivotally connected between drive arm portion 222 a and drive portion 280 b of output member 280 at pivot points 296 , 297 . The link 270 b ′ crosses over to the opposite side of axis 205 .
[0076] Referring generally to FIGS. 8-11 and initially to FIG. 8 , a fourth actuator system 400 includes six actuators 403 , 406 , 409 , 412 , 415 ( FIG. 9 ), and 418 ( FIG. 9 ). The actuators are arranged with moment cancellation and are all mechanically coupled to a common output member 421 ( FIG. 12 ) as described in detail below. The actuators may be arranged in pairs that may be dual tandem or simplex pairs. In the case of simplex pair units, one of the actuators in each pair is substituted with a holding device as described above. In the case of loss of power or a jam for an actuator paired with a holding device, the unit drops out of the network and freely rotates. In the case of a dual tandem unit, each actuator is provided with a brake that may be internal or external and a controller such that loss of power for one actuator of the pair results in the other actuator of the pair moving the tandem unit together.
[0077] Output member 421 is configured to engage with a shaft 424 . As shown, the shaft 424 is a spline shaft, however, it will be evident to those of ordinary skill in the art based on this disclosure that other mechanical means for transmitting rotation from the output member 421 may also be used. Reference structure 427 and reference structure 430 are rigid members. A link 433 is fixedly attached to the reference structures 427 , 430 . Reference structure 430 includes bearing 431 .
[0078] Starting at the bottom FIG. 8 , and working counterclockwise, a moment canceling arm 478 is connected to stator 439 of first actuator 403 . The moment canceling arm 478 rotates with the stator 439 about axis 481 . A link 484 is pivotally attached to arm 478 at one end and is pivotally attached to a moment canceling arm 487 connected to the stator 442 of actuator 406 which forms a pair with actuator 403 . Continuing counterclockwise, moment canceling arm 493 is connected to the stator 445 of actuator 409 . The link that connects arm 493 to its neighboring arm 496 has been removed for clarity. Moment canceling arm 496 is connected to stator 448 of actuator 412 . Moment canceling arm 499 is connected to stator 451 of actuator 415 . A link 502 is pivotally attached to arm 499 at one end and is pivotally attached to arm 505 at the opposite end. Arm 505 is connected to stator 454 of actuator 418 . The rotors 457 , 460 , 463 etc. are disposed between reference structures 427 and 430 and rotate relative to their respective stators. The rotors are coupled to the output member 421 as described in detail below.
[0079] Reference structure 427 includes bearings 436 (best shown in FIG. 15 ) for holding Stators 439 , 442 , 445 , 448 , 451 , and 454 ( FIG. 13 ) in rotary engagement for rotation relative to reference structure 427 .
[0080] Turning to FIG. 12 rotors 457 , 460 , 463 , 466 , 469 , 472 are configured and arranged for rotary motion relative to their respective stators. The rotors 457 , 460 , 463 , 466 , 469 , 472 are mechanically coupled to the output member 421 . Starting at the bottom right hand side of FIG. 12 and moving counterclockwise, drive arm portion 511 of rotor 457 rotates with the rotor 457 about axis 514 normal to the page. A link 517 is pivotally connected to drive arm portion 511 at one end and is pivotally connected to a crank 520 at the opposite end. The crank 520 is fixedly attached to the output member 421 . Drive arm portion 523 of rotor 460 rotates with rotor 460 about axis 526 normal to the page. A link 529 is pivotally connected to drive arm portion 523 at a first end and is pivotally connected to a crank 532 at a second end. The crank 532 is fixedly attached to the output member 421 and is positioned below crank 520 with respect to the orientation of FIG. 12 . Drive arm portion 535 of rotor 463 rotates with rotor 463 about axis 538 normal to the page. A link 541 is pivotally connected to drive arm portion 535 at a first end and is pivotally connected to crank 520 at the opposite end. Drive arm portion 544 of rotor 466 rotates with rotor 466 about axis 547 normal to the page. A link 550 is pivotally connected to drive arm portion 544 at a first end and is pivotally connected to crank 532 at the opposite end. Drive arm portion 553 of rotor 469 rotates with rotor 469 about axis 556 normal to the page. A link 557 is pivotally connected to drive arm 553 at a first end and is pivotally connected to crank 520 at the opposite end. Drive arm 559 of rotor 472 rotates with rotor 472 about axis 562 normal to the page. A link 565 is pivotally connected to the drive arm 559 at a first end and is pivotally connected to crank 532 at the opposite end.
[0081] Turning to FIGS. 14 and 15 , exploded perspective views show an actuator 415 . The actuator 415 includes a stator 451 which includes a torque tube 452 connected to the moment canceling arm 499 . All of the parts of the stator 451 are arranged for rotary motion relative to the reference structures 427 , 430 and are configured for relative rotation with its rotor 469 . Rotor 469 has a drive arm portion 553 that is connected to the output member 421 as described above in connection with FIG. 12 . Moment canceling arm 499 of stator 451 is connected to the moment canceling arm 505 of an adjacent actuator 418 by means of link 502 . Arms 499 and 505 are coupled together such that their moment is canceled. The remaining pairs of moment canceling arms 478 and 487 and 493 and 496 are configured the same way to form a network of three actuator units with each unit comprising two actuators connected in the same manner.
[0082] In FIG. 16 , the fourth actuator system 400 is shown with reference structure 430 removed for clarity. At the left side of the figure, the connection of the moment canceling drive arms 499 and 505 by means of link 502 is shown. The link 502 is pivotally attached at a first end to drive arm 499 at pivot point 506 and is pivotally attached to drive arm 505 at the opposite end at pivot point 507 .
[0083] The output member 421 has a splined bore 422 for receiving a splined shaft 424 ( FIG. 8 ). The output member 421 may be provided with cranks 520 and 532 ( FIG. 12 ) that are coupled to the output member 421 such that forces on the cranks 520 and 532 cause the output member 421 to rotate. Rotor 463 is connected to the crank 520 via a connecting rod or link 541 that is pivotally attached to the drive arm portion 535 of rotor 463 at a first end at pivot point 536 and is pivotally attached to the crank 520 at the opposite end at pivot point 537 . The crank 532 is below or to the right in the axial direction with respect to the axis 550 of rotation of the output member 421 . The crank 520 may be provided with a generally triangular shape for connection to three of the rotors and crank 532 may also be provided with a generally triangular shape for connection to the three other rotors.
[0084] Several modifications can be made to the disclosed embodiments. For example, position sensors, resolvers, and/or encoders may be added to actuators and/or any other linkage joint in order to provide useful feedback to a controller. Additionally, torque sensors, and/or tachometers may additionally be added to each actuator output and/or any other link joint in the linkage system to provide further feedback. In dual tandem configurations, one motor in a pair may be of a different type than its corresponding motor. For example, one motor may be a high torque, high velocity motor, whereas the other motor may be a low velocity, high efficiency, high torque motor. Additionally in configurations in which multiple dual tandem pairs are used, brakes may be safely removed since open actuator failures are not a major concern when a second pair of actuators is available to control the output member in the event of an open failure.
[0085] The disclosed embodiments resulted in several significant advantages. The multiply redundant nature of the disclosed configurations provide high fail-safe statistical levels, especially in triplex configurations. Because there is an additional degree of freedom in each actuator pair, a self test may be safely conducted during use in which one actuator moves relative to another actuator without changing the position of the output member. The hexagonal arrangement of the fourth system provides a highly space efficient configuration which allows for arrangement in tightly constrained vehicle frames such as in aircraft airframes.
[0086] Several actuator systems have been shown and described, and several modifications and alternatives have been discussed. Therefore, persons skilled in this art will readily appreciate that various additional changes and modifications may be made without departing from the spirit of the invention, as defined and differentiated by the following claims. | An actuator system having a controlled element configured for rotary movement about a first axis relative to a reference structure; a linkage system between the element and reference structure; a first actuator and a second actuator configured to power a first degree of freedom and an independent second degree of freedom of the linkage system, respectively; the linkage system having a first link configured for rotary movement about a second axis not coincident to the first axis and second link configured for rotary movement about a third axis; the linkage system configured such that a first angle of rotation may be driven independently of a second angle of rotation between said first link and said reference structure; wherein one of the first or second actuators is configured and arranged to drive rotation of the element about the first axis when the other is operatively locked. | 8 |
RELATED APPLICATION
[0001] This patent application is a continuation-in-part of co-pending patent application Ser. No. 10/735,781 filed Dec. 16, 2003 for “Disposable Adhesive Delivery Pad for Dental Cleaning Pastes and Solutions,” priority from which is hereby claimed.
FIELD OF THE INVENTION
[0002] The present invention relates to devices for hand-holding tooth preparation compounds in dentistry. More specifically, it relates to an article holding device which is adhesively attached to the dentist's or hygienist's glove.
BACKGROUND OF THE INVENTION
[0003] In dentistry, a dental cleaning is called a prophylaxis and the cleaning paste is called prophylaxis paste. Such paste is most commonly provided in two ways: either in bulk in a large container from which one scoops out a portion with a spatula, or in individual dose cups. The paste is usually placed into a plastic or metal cup retainer attached to the dentist's or hygienist's gloved finger as it is being used. The individual dose cups are sometimes attached to the glove by an adhesive to retain the cup to the glove as shown for example in U.S. Pat. No. 4,988,296 to Spencer. U.S. Pat. No. 6,257,888 issued to Barham shows a tray-like holder for dental paste which also holds a dental instrument wiping medium. The tray is secured to the clinician's glove by an adhesive. U.S. Pat. Nos. 4,976,615 to Kravitz and 6,036,490 to Johnsen et al. disclose finger-mounted dental instrument delivery platforms. The platforms are secured to the finger by a clip. The problem with some of these systems of holding the working compound or dental devices is that the plastic or metal holders traditionally used require cleaning and sterilization.
SUMMARY OF THE INVENTION
[0004] In order to solve the problems in the art described above, the present disposable adhesive pad has been devised. The invention comprises a foil sheet of semi-rigid laminated material which includes adhesive on portions of opposing top and bottom surfaces. On a portion of the top side an adhesive is covered by a peel-off label that preferably includes advertising. The remainder of the top surface is a substantially frictionless foil surface. The opposite bottom side is also provided with an adhesive on a portion of its surface. The foil is a medical metal foil that is insoluble in saliva, prophylactic paste, or water.
[0005] The device is substantially planar, however two wings may be formed along foldlines which provide sidewalls that extend upwardly from the top surface and contain the paste, holding it on the foil portion of the delivery pad. If the adjacent walled portion is used to contain the paste, it may be picked up by the rotating rubber cleaning cup as needed during the dental cleaning. When the top side label is peeled off, the adhesive underneath is available for placement of the dose cup type of prophylactic paste packaging. Once the cleaning is completed, the rubber glove is removed and the delivery pad discarded along with any residual paste.
[0006] The delivery pad of the invention also may serve as a releaseable retention surface for small dental instruments and other materials utilized in procedures other than cleaning. For example, the adhesive pad can also be used for presentation and delivery of dental restorative materials, bonding agents, resin sealants, orthodontic brackets, and other orthodontic hardware. It can also be used to hold porcelain veneers or other indirect dental restorations that need to be presented to the mouth for placement. It could also be useful in the specialty of prosthodontics and oral surgery when placing small attachments such as screws. Thus, the delivery pad may function as a service platform for compounds and solutions on the delivery portion foil area while functioning as a temporary holder for instruments and accessories on the adhesive portion.
[0007] Thus, the present invention provides a totally disposable device that offers a multitude of uses as a delivery service platform for the dentist. Advantages include clinical time-savings and the clinical convenience of having materials and small hand instruments directly accessible in the field of operation because there is less reaching and less passing of instruments between the dentist and assistant. The delivery pad of the invention follows the medical model for one-use-per-patient, eliminating cross-contamination and sterility problems and the low cost of manufacturing the device makes disposability practical. However, the chief advantage of the invention is that it makes for easier one-person operation. Other objects and advantages of the present invention will be readily apparent to those of skill in the art from the following drawings and description of the preferred embodiments.
DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a front elevation view of a series of disposable pads positioned on a carrier strip. One pad is partially peeled back to expose the adhesive on the bottom side.
[0009] FIG. 2 is a top right front perspective view of a delivery pad of the invention.
[0010] FIG. 3 is a top right front perspective view with angled sidewalls folded upwardly.
[0011] FIG. 4 is a top left rear perspective view of the present invention placed on a gloved hand while in use.
[0012] FIG. 5 is a front view of the invention.
[0013] FIG. 6 is a front view of the invention with the label partially peeled from the top side of the delivery pad.
[0014] FIG. 7 is a top front isometric view of the invention alternately used to adhesively hold a prophylactic dose cup on the glove of the dental clinician or hygienist.
[0015] FIG. 8 is a top front isometric view of the invention alternately used to hold a dental material and adhesively secure a small dental instrument.
[0016] FIG. 9 is a top front isometric view showing the dental instrument released from the adhesive holding portion of the delivery pad and being manually applied to the contained dental material.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] Referring now to FIG. 1 , the present invention is shown in its bulk manufactured state comprising a plurality of delivery pads 7 adhesively held on the manufacturing carrier strip 9 . Because the invention is comprised of several adhesively laminated paper components, it may be produced inexpensively by label manufacturing equipment. Each individual delivery pad may be peeled off the carrier strip as it is needed just before use. The pad farthest to the right in FIG. 1 reveals an adhesive 10 on the bottom side of the pad, which after removal from the carrier strip, is immediately pressed against the hand or clinician's glove to hold the pad in place as shown in FIG. 4 below. The bottom side adhesive material does not cover the undersides of the fold-up wings 14 but covers the rest of the underside to provide firm attachment to the glove. As an alternative to coverage by a carrier strip, the bottom of individual pads may have a separate peel-off cover.
[0018] Referring now to FIG. 2 , the delivery pad of the invention includes two main portions, a containment or delivery portion 11 and an attachment portion 13 . The attachment portion includes a top side adhesive covered by a releasable paper label that preferably includes advertising 15 . Scored foldlines 17 and 19 on the delivery portion allow sides of the delivery pad to fold upwardly to provide containment sidewalls 14 for a dental paste or other working material as shown in FIG. 3 . The top side label and the peel-off bottom cover may include a tab or portion along the edge that is not secured by adhesive to facilitate grasping and removal.
[0019] Referring now to FIG. 4 , the delivery pad 7 is shown attached to the glove 18 of the clinician with the sidewall wings folded upwardly to create a containment pocket on the delivery portion so that the paste 16 may be scooped in the usual fashion with the rubber cleaning cup of the clinician's handpiece 21 . A metal foil provides an ideal surface of reduced friction to adequately hold the paste yet permits its easy removal. The foil material is preferably of the type such as 7 pt. 5 silver foil laminated board produced by the Fasson Roll North America, a division of Avery Dennison.
[0020] Referring now to FIGS. 5, 6 , and 7 , the present invention is shown in a different application. As shown in FIG. 5 , the invention is identical having a delivery portion 11 and attachment portion 13 except that as illustrated in FIG. 6 , the top paper cover 24 of the attachment portion 13 of the label is removed to reveal an adhesive layer 23 underneath. The result is a foil substrate with adhesive on both sides. When in use as shown in FIG. 7 , one side holds the foil board 25 to the glove 27 while the top side may be used to hold a dose cup 29 for prophylactic paste or other dental material thus securing the cup to the glove. In this application, the delivery pad is not used but it provides a second utility for the invention if the clinician desires to use a dose cup.
[0021] The present device may serve other uses and may provide a disposable adhesive delivery pad for application of other dental materials. For example, as shown in FIGS. 8 and 9 , the dentist or hygienist is shown applying a bonded resin sealant to a tooth. A portion of liquid resin 30 could be carried on the non-adhesive section of the delivery pad for pick-up by a microbrush applicator 32 . The adhesive section of the top of the pad 33 can be exposed to serve as a releasable attachment mechanism to secure the applicator 32 at times when not needed. This is exceptionally helpful when a procedure is being performed by a sole operator, who has no assistant from whom to receive materials or instruments. Another practical example which would provide such a convenience would be when an orthodontic assistant who has the chore of bonding many orthodontic brackets to teeth using light-cured resin material. The delivery pad of the invention therefore serves as not only a holder for dental pastes and solutions but also as a temporary holder for small dental instruments and other loose hardware, implements, or articles.
[0022] From the foregoing, it will be readily understood by those of skill in the art that the present invention provides both a disposable dental paste delivery system for bulk dental pastes or other dental materials and also a convenient means of attachment of material packaged in the form of a dose cup. The non-adhesive portion of the pad may also be used to serve as a delivery point for various types of dental materials such as dental cements, resin restorative materials, or even medicaments that need to be applied to structures in the mouth. Furthermore, as mentioned above, the adhesive portion of the top surface of the pad may be used to temporarily secure a small applicator brush or instrument or provide a surface for attachment of any small item that the dentist or hygienist may need to complete a dental procedure.
[0023] Because it can be inexpensively produced by label-printing manufacturing methods, the addition of printed advertising on the top cover of the attachment portion may be inexpensively included as an additional benefit. Also, although the preferred embodiment shows the use of two upwardly folded angled sidewalls, it will be understood that a greater number of sidewalls formed along additional foldlines may similarly be employed to contain the working material. It should be understood that there may be other modifications and changes to the present invention that will be obvious to those of skill in the art from the foregoing description, however, the present invention should be limited only by the following claims and their legal equivalents. | A double-stick delivery pad for dental materials is attached to the gloved hand of a clinician. The delivery pad may serve as a holder for materials such as a prophylactic cleaning paste or as a releaseable retention service for small dental instruments in other accessories utilized in procedures other than cleaning. The adhesive pad can be used for presentation and delivery of dental restorative materials, bonding agents, resin sealants, orthodontic brackets, and other orthodontic hardware. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a multiple-stage type electrical switchboard, and more particularly to an improved lifting apparatus which lifts up electrical devices such as circuit breakers and draws them into the multiple-stage electrical switchboard and draws them out.
Generally, as shown in FIGS. 1 and 2, a multiple-stage electrical switchboard 10 which contains a plurality of compartments for electrical devices, a lifting apparatus frame 12 which consists of a bucket 14 mounting electrical devices 16, driving gear 18 and trucks 20 is used to facilitate racking movement of electrical devices 16 between positions of electrical engagement and disengagement.
But in this case, not only does the weight and bulk of the lifting apparatus frame 12 become difficult for an electrician to handle, but such is expensive because the lifting apparatus frame 12 contains guide rails 22 which are also used for supporting the bucket 14. It is also necessary to provide the lifting apparatus frame 12 with an area for moving, that is, a passage space for inspection corresponding to the width A and the relatively large accommodating space corresponding to the area BXC as shown in FIG. 2 in front of the electrical switchboard 10.
Furthermore, such lifting apparatus frame 12 is in danger of being turned upside down during jolting on the rough floor such as when an electrician may carelessly move the lifting apparatus frame 12 with the bucket 14 mounting electrical devices on the top of the lifting apparatus frame 12.
SUMMARY OF THE INVENTION
It is a general object of the present invention to provide an improved lifting apparatus capable of easily racking electrical devices in an electrical switchboard.
An additional object of the present invention is to provide a lifting apparatus of the above-noted character, which reduces the necessary areas for moving and accommodating such lifting apparatus with respect to the electrical switchboard.
A further object of the invention is to provide a lifting apparatus of the above-noted character, with a reduced weight and bulk.
Still another object of the present invention is to provide a lifting apparatus of the above-noted character capable of reducing the probability of being turned upside down when moving.
Yet another object of the present invention is to provide a lifting apparatus of the above-noted character, which is inexpensive to manufacture, efficient in design and reliable in operation.
Other objects of the invention will in part be obvious and in part appear hereinafter.
In accordance with the present invention, there is provided a lifting apparatus for racking relatively large heavy electrical devices into and out of an electrical switchboard. The lifting apparatus of the invention includes a carriage on which the electrical device, for example, a large circuit breaker, is mounted. The carriage, in turn, is supported on opposed guide rails mounted to the enclosure, which may be in the form of an electrical switchboard or the like. The rails accommodate facile movement of the carriage from a ground position to the engaged position.
From the disengaged or ground position, racking movement to an engaged position is effected via a wire rope which is pulled by a racking screw or via a rack and pinion combination. The racking screw and rack and pinion combination are actuated by an electrical motor or manual handle.
Guide rails are detachably mounted to an electrical switchboard to prevent the carriage mounted electrical devices from turning upside down by inadvertent movement. When the electrical devices are in an engaged position, the lifting apparatus will be disengaged from the guide rails, and the guide rails, in turn, will be disengaged from the electrical switchboard if necessary.
The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the corresponding claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description when considered in connection with the accompanying drawings in which like reference characters designate like or corresponding parts throughout the several views, and wherein:
FIG. 1 is a side view of a conventional lifting apparatus frame mounting a circuit breaker;
FIG. 2 is a plan view of the lifting apparatus frame of FIG. 1;
FIG. 3 is a side view of the lifting apparatus mounting a circuit breaker embodying the present invention;
FIG. 4 is a plan view of the lifting apparatus of FIG. 3;
FIG. 5 is an enlarged perspective view of the lifting apparatus embodying the present invention;
FIG. 6 is a side view of a portion of FIG. 5, illustrating the bucket, the rollers which are attached to the bucket and the guide rails along which the rollers move;
FIG. 7 is a sectional view taken substantially along the lines VII--VII of FIG. 6, as seen in the direction of the arrows;
FIG. 8 illustrates a modification of the apparatus;
FIG. 9 illustrates a portion of the modified apparatus illustrated in FIG. 8;
FIG. 10 illustrates a portion of the further modification of the apparatus; and
FIG. 11 illustrates still another modification of the apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and more particularly to FIGS. 3 and 4 thereof, the present invention is embodied in a lifting mechanism for facilitating racking movement of the electrical device 16, e.g. a large circuit breaker movable into or out of a cubicle or compartment of an electrical switchboard 10. The circuit breaker 16 is mounted on a carriage 24, which contains a bucket 26 and wheels 28, which in turn are supported for racking movement by opposed guide rails, indicated by reference numeral 30, and moves up and down along guide rails 30.
The guide rails 30 are mounted to box frame 32 which is contained in the electrical switchboard 10. The carriage 24 is smaller, lighter and less expensive than the conventional lifting apparatus frame 12 because the carriage 24 does not contain the guide rails 30 in itself. Further, the lifting mechanism according to an embodiment of this invention reduces the area of movement, that is, the passage space for inspection corresponding to length D and the accommodating space for the carriage 24 corresponding to the area EXF as shown in FIG. 4 in front of the electrical switchboard 10. Furthermore, the center of gravity of the carriage 24 mounting electrical device 16 is so low that the carriage 24 is not in danger of being turned upside down as a result of jolting on the rough floor. Because the carriage 24 mounting the electrical device 16 is carried on the rough floor via wheels 28 which are attached to the carriage 24, the required strength of the guide rails 22 can be reduced because the guide rails 22 share the weight of carriage 24 mounting the electrical device 16 with the box frame 32 to which the guide rails 22 are attached.
Referring now to FIGS. 5 and 6, the detailed construction of the carriage 24 is shown therein. The carriage 24 consists of a bucket 26 mounting an electrical device 16 (not shown in FIG. 5) and a driving device 34 and wheels 28. Vertically elongated guide rails 30 are affixed to the box frame 32 (not shown in FIG. 5) for the purpose of supporting the carriage 24 via rollers 36 which are attached to the bucket 26, as will be discussed more fully hereinafter.
A mounting plate 38, hinged to the end of the bucket 26, constitutes not only the end side of the bucket 26, but also the sloped guide plate for mounting the electrical device 16. In order to mount the electrical device 16 into the bucket 26 located on the ground, when the mounting plate 38 is lowered (as indicated by G) to form a sloped guide plate 38, the electrical device 16 can be disposed in the bucket 26 by sliding the electrical device 16 on the sloped guide plate 38, via wheels if necessary, by application of a slight force which makes the electrical device 16 climb over the sloped guide plate 38, without lifting up the electrical device 16.
The wheels 28 affixed to the base of the bucket 26 are casters which enable the carriage 24 to move between electrical switchboards, or from the electrical equipment to the another electrical switchboard, in order to rack the electrical device 16 to the electrical switchboard 10. It is desirable that the number of the wheels 28 is greater than two. All of the wheels 28 are not necessarily caster wheels which can change course. When the wheels 28 are affixed to the side plates of the bucket 26 to reduce the height of the base of the bucket 26 from the floor, the electrical device 16 can easily be disposed in the bucket 26 by making the electrical device 12 climb over the more moderate sloped guide plate 38.
Driving device 34, which drives the carriage 24, consists of a motor 40 and a reduction gear 42 which is connected to a power shaft 44 of motor 40 via a coupling 46 and a drum 48 which is rotatably affixed to the side of the reduction gear 42. The motor 40 is affixed to the side of the bucket 26, is reversably rotatable and can contain a reduction mechanism and controlling mechanism, if necessary. On the other hand, reduction gear 42 is affixed to the side of the bucket 26 and is provided with the self-rocking mechanism which contains a worm wheel. Besides, when the motor 40 contains the controlling mechanism, reduction gear 42 is not necessarily provided with the self-locking mechanism. Furthermore, the output revolution of motor 40 is equal to the predetermined revolution of the drum 48, the drum 48 being directly connected with the power shaft 44 of motor 40 and not via the reduction gear 42. A plug 50 is connected with the motor 40 via a power cable 52. A power switch 54 is connected with the motor 40 via a control cable 56. The drum 48 contains a roller with a peripheral groove or with flange on the opposite end of the roller to wind up a wire rope 58 around the roller, described more fully hereafter.
One of the ends of the wire rope 58 is connected with the drum 48 and the other end of the wire rope 58 is connected with the bucket 26 via pulleys 60, 62 which are rotatably affixed to the side far 64 which is contained in the box frame 32. The pulleys 60, 62 may be affixed to the upper part of the guide rails 30 instead of the side far 64, if necessary. One or both of the ends of wire rope 58 are detachably connected with the bucket 26 or the drum 48 respectively. Therefore, we can raise, lower or stop the carriage 24 by winding or unwinding the wire rope 58 via the motor 40.
Crank arm 66 is detachably affixed to the motor 40 via a coupling 68 in order to achieve the movement of the carriage 24 when electrical supply is not equipped.
Guide rails 30 are vertically elongated along the box frame 32 and may well be either detachably affixed to the box frame 32 or consist of the box frame 32. Furthermore, the cross-sectional shape of the guide rail 30 is not necessarily L-shaped.
FIG. 6 is the side view of the carriage 24 and shows only the connecting mechanism between carriage 24 and guide rails 30. Therefore, no other device except the connecting mechanism are shown in FIG. 6. Rollers 36 and 37 are rotatably connected to the supporting boards 70 via L-shaped plate 72. Furthermore, the supporting boards 70 are connected to the bucket 26 via hinges 74. Normally the supporting boards 70 are connected to the both sides of the bucket 26, but some of the supporting boards which are connected to the one side of the bucket 26 may be fixed to the bucket 26.
Referring to FIG. 7, when the electrician engages the rollers 36 and 37 with guide rails 30, the supporting boards 70 are inwardly pivoted on the hinge 74 to the position indicated at H in the bucket 26, and the carriage 24 is then inserted between the guide rails 30, and the supporting boards 70 are pushed outwardly to the position indicated at J (FIG. 7) and fixed to the sideplate of the bucket 26 by locks 76 which are fixed to the supporting boards 70. Thus, mechanically controlled ascending or descending movement of the carriage 24 along the guide rails 30 by means of the connecting mechanism between the rollers 36, 37 and the guide rails 30 is provided.
Regarding accommodation of electrical devices 16 into the compartment of the electrical switchboard 10, the electrician mounts the electrical device 16 on the carriage 24 by means of sliding it along the sloped mounting plate 38 (as shown by G). He then inserts the carriage 24 with the supporting board 70 turned inwardly between guide rails 30, and turns the supporting board 70 outwardly to engage the rollers 36,37 with the guide rails 30. He can raise carriage 24 upon which the electrical device 16 is mounted along the guide rails 30 and stop the carriage 24 at the predetermined height that corresponds to the vacant compartment of the electrical switchboard 10 to thus position the electrical device 16 within the compartment of the electrical switchboard 10.
In turn, regarding movement of electrical device 16 out of the compartment of the electrical switchboard 10, the electrician handles the lifting apparatus in the inverse manner stated above.
FIGS. 8 and 9 set forth another embodiment of this invention. Racks 80 are attached to the guide rails 30, and pinions 82 are supported by bearings 84 via a shaft 86. The pulley 88 is attached to the end of the shaft 86, and connected with the drum 48 via a belt 90. The pinions 82 are driven by the pulley 88 via belt 90 which is driven by the drum 48. The pinions 82 are engaged with the racks 80. Thus the pinion and rack combination substitutes for the wire rope 58 and rollers 60 and 62 (in FIG. 5).
FIG. 10 is the modification of the aforementioned embodiment. Chain assembly 92 is attached to the guide rails 30 instead of the racks 80. The pinion 82 is engaged with chain assembly 92.
FIG. 11 is still another embodiment of this invention. A drum 94 is supported by bearing 84 via a shaft 86. One of the ends of the wire rope 58 is connected with a drum 94 and the other end of the wire rope 58 is connected with the side bar 64 via a pin 96. The drum 94 consists of same structure as the drum 48 aforementioned.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A lifting mechanism including a carriage mounting a circuit breaker, a disconnecting switch and the like and supported on guide rails to facilitate racking movement of the circuit breaker, disconnecting switch and the like between the positions of electrical engagement and disengagement. The carriage includes a bucket upon which is mounted electrical devices, e.g. a circuit breaker, a disconnecting switch and rollers to transfer a bucket which moves along the guide rails which are detachably engaged in an electrical switchboard. | 7 |
BACKGROUND OF THE INVENTION
Therapeutic tables, or beds, of the type which have a frame, a patient support mounted to the frame for periodic, reciprocal rocking or tilting movement, a power drive train for such movement and a controller for the drive train are well known. Examples of such tables are shown in international application No. PCT/US83/01298, published Mar. 14, 1985, under Publication No. WO 85/0097, and the patents cited therein.
Electronic controllers for such tables are shown both in the aforementioned, patent application and in the following U.S. Pat. Nos.: 3,247,528 of Swenson et al.; 3,793,652 of Linehan et al.; 4,277,857 of Szehaug; and 4,194,499 of Donnelly, Jr.
In the table of the aforementioned patent application, the patient support is mounted to the frame for pivotal movement around its elongated axis in a side-to-side periodic tilting action. In addition, its pitch, or Trandelenberg angle, is adjustable to permit tilting of the bed around an axis transverse to its elongate axis. This type of Trandelenberg positioning is also shown in the above U.S. patents.
An important consideration in the beneficial use of such therapeutic tables is the reliability of control. In the controller of the aforementioned patent application, the amount of movement was controlled via the timing that drive powered was applied. It was assumed the drive would operate at a fixed rate and thus if it operated for a known time, the degree of tilt could be controlled. While this approach functions satisfactorily, it, of course, lacks the positive and absolute control that can be achieved only by direct measurement of the tilt angles during the periodic movement of the patient support.
In any event, the degree of maximum tilt on either side of a horizontal reference should be adjustable independently of one another. While independent control of the degree of tilt to both the left and the right of horizontal was achieved with the controller of the aforementioned patent application, such control again relied upon the timers and asumptions concerning drive speed.
When the movements of the patient support relative to the frame of the therapeutic table are powered by means such as electric motors, it is imperative from both a safety and an equipment protection viewpoint to minimize the continuation of drive power in the event of a jam condition. Such a jam condition could result from other hospital equipment interfering with the movement of the patient support. While the use of slip clutches and emergency clutch release mechanisms are known, these approaches do not function to automatically correct the jammed condition, although they may alleviate it. Instead, they depend upon operator involvement to correct the jammed condition.
Another difficulty with known therapeutic tables is that the setting of tilt limits has often been cumbersome or awkward and displays and other feedback information to the operator have been less than adequate to facilitate easy set-up operation and monitoring.
SUMMARY OF THE INVENTION
It is therefore a principal object of the present invention to provide an improved controller for a therapeutic table which overcomes or alleviates the problems or disadvantages of known controllers such as those noted above.
This objective is achieved in part through provision of a controller for therapeutic table in which the reliability is improved through measurement and direct feedback of the actual angular positions of the patient support during relative movement thereof with respect to the frame of the therapeutic table. In a preferred embodiment, the controller comprises means for electronically sensing a plurality of successive positions of the patient support during relative movement thereof, means for electronically encoding a preselected positional reference, means for successively comparing the sensed relative positions with the angular positional reference during said relative movement and means for controlling the drive mechanism in accordance with that comparison. The sensing means senses the angle of tilt of the patient support such as a synchronized shaft encoder.
Thus, it is a particular object of the present invention to provide an improved controller comprising means for sensing the angular position of the patient support relative to the horizontal position on either side thereof, means for preselecting a first angular reference position on one side of the horizontal position, means for preselecting a second angular reference position on the other side of the horizontal position opposite the one side independently of preselection of the first angular position, means for causing the patient support to rotate in one direction until it reaches said first angular reference position and means for causing the patient support to rotate in another direction opposite said one direction when it reaches said second angular reference position. In a preferred embodiment, the patient support is caused to momentarily pause when it reaches either of the preselected angular reference positions to minimize rapid direction reversals. In addition, the controller includes simple means, such as thumb-wheel encoders, for manually preselecting each of the preselected reference angles and has means associated with the preselecting means for displaying a numerical indication of either the preselections or the actual tilt angle.
Yet another feature of the present invention is the provision of means for preventing preselection of an angular position beyond a preselected maximum limit position. In such event, a visual indication is provided of the invalid input selection and the starting of operations is inhibited. A further safety advantage is achieved through achievement of another objective which is provision of an improved controller for controlling the relative movement of a patient support of a therapeutic table comprising means for controlling a drive mechanism for movement of the patient support in accordance with a comparison between the mechanical work required for the relative movement as measured by suitable sensor with a preselected mechanical work reference. In the event of a jam condition, the mechanical work required for the relative movement dramatically increases and this phenomenon is used to sense the jammed condition directly so that immediate corrective action can be taken. In a preferred embodiment, the mechanical work measuring includes a strain gauge for measuring strain on a member which varies with variations with the mechanical work required to move the patient support. In a preferred embodiment, the jammed condition is automatically corrected, for the controlling means causes the patient support to rotate in a direction opposite to the direction it was going when the jammed condition arose for a preselected brief time period before power is terminated. The fault condition indicator then informs the operator that a fault condition has previously occurred.
The objective of improved safety is further achieved through achievement of another object of the invention of providing an improved controller for a therapeutic table comprising means for controlling a drive mechanism for powering periodic relative movement of the patient support to cause periodic reversal of the relative movement of the patient support, means for sensing a fault condition and means responsive to the sensing means to reverse relative movement of the patient support irremediate periodic reversals. In the preferred embodiment, the fault condition not only includes the jam condition as noted above, but may also include the condition of excessive tilting beyond a limit set by a fail-safe limit switch. In such case, the direction of rotation of the drive mechanism is reversed and power continues to be applied until the patient support returns to a horizontal position at which time power is terminated and a fault indication is provided.
Greater safety and equipment protection is further achieved with the present invention through achievement of the particular object of providing an improved controller for a therapeutic table having a frame, a patient support movably mounted to the frame, a motor and means including a clutch for applying drive power from the motor to the patient support to cause periodic reciprocal relative movement of the patient support in which means are provided for detecting such disengagement and means responsive to clutch disengagement for removing electrical power from the motor. In a preferred embodiment, if such a condition occurs, the patient support must be returned to a horizontal position before a fault indication is terminated and the controller is again enabled to operate in a normal fashion.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing objects, features and advantages will be described in greater detail and further advantageous features will be made apparent from a reading of the following detailed description which is given with reference to the several figures of the drawings, in which:
FIG. 1 is a broad functional block diagram of the controller 10 in combination with a therapeutic table having both a tilt motor and a Trandelenberg or pitch angle motor;
FIG. 2 is a schemmatic plan view of the control panel functional block of FIG. 1;
FIG. 3 is a detailed functional block diagram corresponding to the functional block diagram of the controller of FIG. 1; and
FIG. 4 is a partially schemmatic, partially functional block diagram of a preferred circuit embodiment of the controller of FIG. 1.
DETAILED DESCRIPTION
Referring now to FIG. 1, the controller 10 as used with a therapeutic table 12 is illustrated in functional block form. The details of the structure of the therapeutic table 12 form no part of the present invention, but if such information is sought, a suitable therapeutic table for use with the controller 10 is disclosed in PCT application No. PCT/US83/01298 published Mar. 14, 1985 under International Publication No. WO 85/00967 and entitled "Therapeutic Table". Other beds or tables having movable patient support surfaces are shown in the patents cited in the aforementioned PCT application and also in the patents cited above in this application.
Briefly, the therapeutic table 12 includes a frame 14 to which a patient support 16 is mounted for relative movement via a suitable movable mounting apparatus 18. In a preferred embodiment, the patient support 16 is mounted for rotatable movement about an elongate center axis of the bed to enable it to periodically and reciprocally pivot, or tilt, from one side of horizontal to the other. Power for such rotary or tilting movement of the patient support is provided by a reversible tilt angle motor 20 mounted to frame 14 and connected to the patient support 16 through a rotary drive mechanism or system 22 including a manually actuatable release clutch. When the tilt angle motor 20 receives electrical power at its input 24, it rotates in one of two directions which, accordingly, causes the patient support 16 to tilt either away or toward a horizontal position.
The direction in which the tilt angle motor 20 rotates depends upon the state of direction input 26. If the direction input 26 is in one state, such as a logic 1-state, then the tilt angle motor rotates in one direction and the patient support is driven to tilt in an associated direction, such as to the left. If the direction input 26 is in an opposite state, such as a logic 0-state, then the tilt angle motor rotates in an opposite direction, and the patient support pivots or tilts in the associated opposite direction, such as to the right.
The patient support 16 is also mounted for relative pivotal movement about transverse axes to enable the head of the patient support 16 to be raised or lowered to a level higher or lower than the opposite foot end of the patient support 16. When the foot end of the patient support 16 is above the level of the head end, the patient support 16 is said to be in a Trendelenberg position. When the foot end of the patient support 16 is lower than the head end, the patient support 16 is said to be in a reverse Trandelenberg position.
The angle that the elongate axis of the patient support 16 makes with respect to a horizontal plane is referred to herein as the Trendelenberg angle, or pitch angle. The pitch angle of the patient support 16 is controlled through means of a pair of reversible pitch angle motors 28 which are mounted to frame 14 and respectively connected to patient support 16 through direct vertical drive mechanism, or systems, 30A and 30B at the head end and foot end of the table. When one of the pitch angle motors 28 rotates in one direction, the end of the patient support 16 to which it is connected is raised, and when the pitch angle motor 28 is caused to rotate in the opposite direction, that end of the patient suport 16 is lowered. Both the application of power on input power leads 32A and 34A and the direction of rotation signal on a direction inputs 32B and 34B are manually selected from manual inputs 36 of a control panel 38.
As also seen in FIG. 2, the control panel 38 includes a display 40 including a Trandelenberg angle, or pitch angle, display unit 40A. The inputs 36 also includes up/down rocker switches 36A and 36A' which selectively control the application of power to power inputs 32A and 34A, respectively, and of direction input signals to direction inputs 32B and 34B. It is intended that the operator will actuate one or both of the up/down switches 36A and 36A' for movement in the desired direction until the desired Trandelenberg angle which has been selected by the operator is displayed at display unit 40A. Upon release of either one of the up/down rocker switches 36A and 36A', it automatically returns to a neutral position. As will be explained in more detail hereinafter, the display 40A receives pitch angle information from the output of a pitch angle detector 42 which, in turn, receives pitch angle sensor data from a rotary shaft encoder.
Referring again to FIG. 2, unlike the Trendelenberg control portion of the controller 10, the tilt ang1e control portion of the controller 10 operates automatically. As seen, instead of up/down rocker switch 36A and 36A', two pairs of thumb wheel tilt angle selection encoders 36B and 36C are provided for respectively selecting a left tilt angle, or right preselected positional reference, and a right tilt angle, or right preselected positional reference. Any angle between zero degrees and 69 degrees may be selected, and the choice of the left tilt angle is selectable independently of the selection of the right positional reference.
The tilt angle detected by pitch angle detector 42 is shown in display unit 40B for monitoring purposes only. Once a start/stop input switch 36D is placed in its start position and a valid start condition is achieved, the controller 10, as will be explained, works automatically to slowly tilt the patient support 16 in one direction until the associated positional reference selected on one of the thumb wheel encoder 36B and 36C is reached. Then, after a short pause, the controller 10 causes the patient support 16 to tilt in the opposite direction until the other selected tilt angle positional reference on the other of the thumb wheels has been reached. So long as this automatic operation continues, a run light indicator 40C is lit, but when a fault condition occurs, the run lamp 40C is turned off and a fault indicator lamp 40D is lit instead. A further output indicator comprises an input error lamp 40E which is lit in the event a tilt angle in excess of 69 degrees is selected on either of the selection thumb wheel encoding 36B and 36C.
Referring still to FIG. 1, the controller 10 is seen to include, in addition to control panel 38 and pitch angle detector 42, a tilt angle detector 46, an electronic tilt motor control 48 and fault condition sensors 50. The fault condition sensors 50 include status sensors 52 and, in keeping with an important aspect of the present invention, a jam detector 54.
As will be explained in greater detail with reference to FIGS. 3 and 4, the tilt angle detector 46 functions to electronically sense a plurality of successive angular positions of the patient support during relative movement thereof. These tilt angles are successively compared with the selected one of the angular positional references manually chosen through means of thumb wheel encoders 36B and 36C, as noted above. The two positional references are, in effect, mechanically stored by virtue of the physical positions of the thumb wheel which also encodes them. The selected one of the encoded positional references is then selected by means included in the tilt angle detector 46. During normal operation, the patient support 16 periodically tilts from side to side. However, in the event of a fault condition, this normal cycle is interrupted and a fault indicates lamp is activated.
Referring now to FIG. 3, the output 56 of tilt angle detector 46 is seen to be taken from a tilt angle comparitor 62 which compares an actual tilt angle signal applied to its input 64 with a selected one of a pair of binarily encoded selected tilt angles applied to its input 66. The binarily encoded detected tilt angles applied to input 64 is taken from a tilt angle sensor 68. The tilt angle sensor 68 can be any of various types of sensors capable of determining the tilt of the patient's support 16 relative to a horizontal reference and encoding that into a suitable electrical signal.
However, preferably, the tilt angle sensor comprises a shaft encoder connected to tilt angle motor 20 via a linkage 70. While various types of shaft encoders can be employed, preferably the shaft encoder is an optical incremental shaft encoder which produces one leading and one lagging output pulse for each one degree of rotation and, in addition, produces one reference pulse per cycle. While an absolute positioning encoder could be employed, such an absolute positioning encoder is presently significantly more expensive than an incremental encoder, and accordingly one is not employed even though from a functional viewpoint it might be preferred.
Advantageously, the additional expense of an absolute positioning encoder is avoided through use of a unique synchronizing circuit to ensure that a given pulse count corresponds to only one tilt angle position. Briefly, the setting and count enablement of a binary counter is synchronized with a horizontal position sensor and the output reference pulse from the shaft encoder. The binary output of the counter as presented to input 64 of tilt angle comparitor 62 therefore represents a particular and unique angular tilt position of the patient support 16.
The binary coded signal applied to input 66 is supplied by a left/right tilt reference selection circuit 72. The tilt reference selection circuit 72 has two sets of binary encoded inputs 74B and 74C respectively representative of the angles selected from tilt angles selection encoders 36B and 36C of FIG. 2. The tilt reference selection circuit also has a selection input 76 obtained from electronic tilt motor control 48.
Whenever the electronic tilt motor control 48 senses a condition from its various inputs calling for reversal of the tilting motion of patient's support 16, it generates one of two binary signals representative thereof, and the left/right tilt selector circuit applies a corresponding binarily encoded left or right tilt angle reference at inputs 74B and 74C to input 66 of the tilt angle comparitor 62. As soon as the binary code at input 64 is the same as the binary code at input 66, the tilt angle comparitor 62 generates a comparison detection signal on its output 56 which is applied to an input 78 of electronic tilt motor control 48.
In response to this signal, the electronic tilt motor control 48 also reverses the polarity on direction outputs 26 to reverse the direction of tilt angle motor 20. It also momentarily removes power from power input 24 to cause the motor to momentarily pause before reversing direction.
Once started, the controller 10 continues to operate automatically in this fashion unless an override signal is applied to one of five override inputs 80A and 80B, 82, 84, 86 and 88. During normal operation, an actuation signal is provided on an output 90 of electronic tilt motor control 48 which is applied to actuate run lamp 40C. In the event one of the override signals is applied to any of the override inputs 80A through 88, however, the run actuation signal is removed from output 90 and a fault actuation signal is generated on an output 92 which is applied to a fault lamp 40D.
The fault condition sensors include four status sensors which are respectively coupled to override inputs 80A and 80B, 82, 84 and 86. The inputs 80A and 80B are respectively coupled to two outputs of a tilt limit detector 92 which comprises a pair of limit switches for respectively providing override signals in the event that the maximum tilt angle to the left or to the right is exceeded. These limit switches may be mechanical motion limit or electronic proximity switches, but in either event, each is actuated in response to the movement of a preselected positional element of the patient support or the rotary drive train into a preselected limit position adjacent to the limit switch.
Input 82 of electronic tilt motor control 48 is received from a head level detector 94. As previously indicated, the patient support 16 includes a head support which is adjustable from a level position with respect to the remainder of the patient support 16 to a raised position. It is desired to avoid relative tilting movement of the patient support 16 when the head support portion is in the raised position. Accordingly, the head level detector 94 includes a switch which is actuated in response to raising of the head support. This results in the application of an override signal to output 82 until the head support is returned to a level condition.
The override signal applied to input 84 is obtained from a clutch engagement detector 96. The drive mechanism 22 including manually deactivatable clutch 23, FIG. 1, may be used in an emergency situation to separate the drive in 22 and thus tilt angle motor 20 from the patient support to allow quick return of the patient support 16 to a horizontal position. When the clutch 23 is disengaged, the tilt angle motor 20 serves no function. There is no need for the application of electrical power to the tilt angle motor 20 and it is desired to stop the movement of the tilt angle motor before the clutch is again re-engaged. Accordingly, the clutch engagement detector includes a switch which is actuated in response to disengagement of the clutch to provide an override signal to input 84 of the electronic tilt motor control 48.
A horizontal pitch detector 98 provides an override signal to override input 86 when the patient support 16 is other than in a level condition when power is first applied to controller 10. This override signal is presented to the electronic tilt motor control 48 only when power is first connected to the unit and the patient support 16 has passed through the horizontal position for the first time. This is required to synchronize a pitch angle sensor 100 and an associated decoder 102 of pitch angle detector 42. The pitch angle sensor 100 is substantially identical to the tilt angle sensor 68 and is preferably also a photo-optical shaft encoder. This horizontal pitch detector includes a flip-flop which is set to enable operation upon actuation of the start switch only after the pitch angle detector has been initialized.
The override signal applied to override input 88 is obtained from the output of a comparitor 104 which compares the output of a mechanical load sensor 106 with the fixed output of a load reference circuit 108. The mechanical load sensor 106 can comprise any number of suitable devices for producing a signal representative of the work required to tiltably rotate the patient support 16. Preferably, the mechanical load sensor includes a strain gauge attached to a member which is strained in a known relationship with changes in the work load. Alternately, the electrical power drawn or produced by the electrical motor can be measured electronically and used to indicate a substantial increase in mechanical work, or power, which results when the free movement of the patient support 16 is interfered with, as if jammed. This fault detection minimizes possible injury or damage to the therapeutic table 12 and the motor 20. The electronic tilt motor control 48 responds to the signals applied to its override inputs in various ways in addition to those indicated above depending upon the nature of the override signal and provides output signals to the various other elements of the controller 10 in manner which is described below with reference to FIG. 4.
Referring now to FIG. 4, the tilt angle detector 46 is seen to include a count enable logic circuit 105, an up/down resettable decade counter 109, a zero 108 and a display decoder 110 in addition to the tilt angle 68, comparitor 62 and left/right tilt reference selector 72. The display decoder 110 simply decodes the binary output from decade counter 106 into a seven bar character code needed for proper operation of tilt angle display 40B. The count enable logic circuit 105 conditions the encoder input signal from tilt angle sensor 68 applied to its input 109 and then provides that conditioned sensor signal to decade counter 106 on its output 112. The count enable logic circuit 104 applies the conditioned tilt angle sensor input signal produced on its output 112 to the input 126 of decade counters 106, but only when the count of decade counters 106 is not zero as detected by zero detector 108. The output of zero detector 107 is applied to an input 118 of count enable logic circuit 105 and the patient support 16 is not in a horizontal position as indicated on the output 114 of a toward TDC detector 116 which is applied to an input 120 in response to a top dead center switch circuit 122 which is applied to an input 124 of toward TDC detector 116.
The decade counters 106 count the encoder pulses applied to its input 126 from count enable logic output 112. One pulse is applied to input 126 for each one degree of rotation, and the direction of the count, either up or down, is determined by a direction signal applied to a direction input 128. When a signal of one logic state is applied to input 128, the decade counter counts in one direction, and when the signal is in an opposite state, it counts in the opposite direction.
The direction input signal 128, in turn, is obtained from an output 130 of the toward TDC detector 116. The zero detector 108 detects when the decade counter 106 has a count of zero and disables the count enable logic from passing any further pulses to input 126 till the top dead center or horizontal position is reached as indicated by the signal on output 114 of toward TDC detector 116. This eliminates the cumulative error that might otherwise develop and insures that an angle of zero degrees is displayed on a tilt angle display 40B when the patient is horizontal. However, once the patient support 16 departs from the horizontal position and the top dead center switch circuit 22 is deactuated, the count enable circuit 105 is again enabled to pass pulses to decade counter 106 and counting, beginning from zero, with the patient support in the horizontal position can then continue.
The display decoder 110 both decodes the binary coded decimal output from decade counters 106 and amplifies the signals to drive the seven segment displays of tilt angle display unit 40B. At the same time, the left/right tilt selector circuits 72 provides a binary coded decimal on its output bus 132. The status of the logic states on these seven input leads of bus 132 is compared to a corresponding seven input leads on an output bus 134 from decade counters 106 by means of the tilt angle comparitor 62.
If the count represented by the logic states of output bus 134 of decade counters 106 is greater than or equal to the selected tilt reference angle represented on bus 132, then a positive comparison pulse is generated on its output 136 which is coupled to the input 78 of the electronic tilt motor control 48. This is applied to an input of an AND-gate 138 which, if it not disabled by the application of a zero state signal to its other input 140 from output 130 of toward TDC detector 116, generates a 1-state control pulse on its output 141 which is passed by OR-gate 142 to the trigger input 144 of a stop and reverse logic-circuit 146. The stop and reverse logic circuit 146, in response to the control pulse applied to its input 144, switches its output 148 to an off or 0-state which is applied to the input of an AND-gate 150. AND-gate 150, in response thereto, deenergizes a run relay 152 which disconnects electrical power to tilt angle motor 20 which would otherwise be applied thereto via power input 24.
The stop and reverse logic circuit includes a timer, having a time delay on the order of 0.5 seconds. After this half-second delay, the stop and reverse logic circuit 146 switches its on/off output 148 to an on state to re-energize run relay 152 and energize tilt angle motor 20. However, at the same time, the stop and reverse logic circuit 146 reverses the polarity of the signal on its direction output leads 153 which are applied to direction relays 154. Direction relays 154, in response thereto, causes the tilt angle motor 20 to reverse its direction via reversing signals applied to direction input leads 26. One of the output direction leads 152 is connected to the select input 76 of the left/right tilt reference selector circuit 72. This causes the left/right tilt selector circuit 72 to terminate the application of the binary encoded reference tilt angle previously being provided on output 132 and substituting therefor the other tilt angle reference. Accordingly, the tilt motor 20 is caused to continue operating and rotating the patient support 16 in the other direction until another comparison pulse is generated on the output 136 of tilt angle comparitor 62.
As previously indicated, this stop and reverse control of tilt motor 20 is also affected under various override conditions which may occur intermediate the normal periodic reversals. Thus, OR-gate 142 has a second input 157 connected to and responsive to the tilt limits detector via the output of an OR gate 156 which has a pair of inputs respectively coupled to tilt limit detector outputs 80A and 80B. Whenever a 1-state pulse appears on either of outputs 80A or 80B when the limit switch associated therewith is actuated, a 1-state pulse is applied to input 157, and OR-gate 142 applies a 1-state pulse to trigger input 144 of the stop and reverse logic circuit 146. This causes the tilt angle motor 20 to stop and reverse as described above.
The output of OR-gate 156 is also coupled to a hold circuit 158, which holds the 1-state signal from OR-gate 156 on its output 160 and applies it to the input of an AND-gate 162. Another input 164 of AND-gate 162 is coupled to the TDC switch circuit output 124 via a lead 166. When the TDC switch circuit is actuated upon the patient support 16 reaching a horizontal level, then a 1-state signal is applied to input 164. When this occurs, AND-gate 162, having been previously enabled by the 1-state output signal on hold circuit 160, generates a 1-state signal on its output 167. This output is applied to an OR-gate 168 which, in turn, generates a 1-state signal on its output 170. The 1-state signal on output 170 triggers an initializing timer 172.
The initializing timer 172, after a short initializing time period on the the order of 300 milliseconds, generates a 1-state tilt initiate signal on its output 174 which is applied via lead 176 and the lead 178 to the reset input 180 of decade counters 106. This tilt initiate signal is also applied via a lead 180 to the input of an OR-gate 182.
OR-gate 182, in response thereto, generates a 1-state signal on its output 184 which is applied to a start/stop latch. Latch 186 is reset thereby to terminate the application of power to a light emitting diode 188 of run lamp 40C.
Likewise, the initializing timer 172, generates a 0-state signal on its output 190 to actuate an LED 192 of fault lamp 40D. At the same time, a 0-state signal is produced on a run output 194 of latch 186 which is applied to another input of AND-gate 150. This causes the run relay 152 to be deactuated to remove power from the tilt motor 20.
Thus, it is seen that in the event of either of the tilt limits detectors being actuated, the tilt motor 20 is caused to reverse its direction after a momentary pause and then to return to a horizontal position. At the same time, the fault indicator lamp 40D is energized and the run indicator lamp 40C is deenergized. Further operation cannnot then be commenced until reactuation of the start/stop switch by the operator. The return to the horizontal position is most important for the comfort of the patient while he awaits the operator correction of the fault condition. Likewise, the continuous indication of the fault is necessary, so that the operator can quickly ascertain that there has been a fault.
Still referring to the latch 186, it is seen that the OR gate 182 which provides the reset pulses latch 186 also has an input 196 that is coupled to an output of the invalid input detector 36E. Whenever either of the tilt angle selection encoders 36D or 36C are set to a tilt angle reference greater than 69 degrees, a 1-state signal is applied to its output 198 which in turn is coupled to input 196 of OR-gate 182. As a consequence, actuation of the start/stop switch 36D which is coupled to latch 186 via a lead 198 is disabled from setting the latch 186 to a run condition. At the same time, the invalid input detector latch 36E produces a 0-state condition on its output 200 to energize an LED 202 of input error lamp 40E.
Referring again to OR-gate 168, it is seen that it also has an input 204 which is coupled to the output of a delay circuit 206 which, in turn, is connected to the output of a differential amplifier, or comparitor, 104 of the jammed detector circuit 54. Thus, when a jam is detected, the differential amplifer, or comparitor, 104 produces a pulse on its output 206 that is coupled to the input 159 of OR-gate 142 to actuate the stop and reverse logic circuit 146 as discussed above. However, the delay circuit 207 delays the application of this pulse to the input 204 or OR-gate 168 to allow the tilt motor 20 to continue to run in a reverse direction opposite to the jammed direction for approximately two seconds.
Thus, it is seen that in the event of detection of a jam not only is power immediately removed from the motor for a brief time period, but it is also then allowed to operate in a reverse direction to relieve any stress or strain that may have been created by the jam in the first instance. This substantially protects the tilt motors 20 against overload damage and also improves the safety of the operation of the therapeutic table.
Referring again to OR-gate 168, it is seen that it also has two inputs 208 and 210 respectively coupled to the head level detector 94 and the clutch engagement detector 96. When either of these detectors are actuated, the OR-gate 168 is caused to trigger the initializing timer 172 as described above to prevent the application of power to the tilt motor 20 by disabling AN gate 150 via latch circuit 186, as described above. However, detection does not actuate the stop and reverse logic circuit as is done in response to actuation of the tilt limits detector circuit 92 or the jam detector 54. Such action is not required since the head level detector is not related to the tilt position of the patient support 16. Likewise, when the clutch is disengaged, the tilt motor 20 cannot provide drive power to move the patient support, in any event. However, as noted above, both the fault indicator lamp 40D is actuated and the run indicator lamp 40C is deactuated in the event of actuation of either of the clutch enagagement detector 96 or the head level detector 94.
Referring still to OR-gate 168, there is one final input 212 which is taken from the horizontal pitch detector 98. As seen, the pitch detector 98 includes a flip-flop 214 with an output coupled to OR-gate input 212 and an input triggered by a zero degree reference encoder pulse from the pitch angle sensor 104. However, once this flip-flop 214 is set after power has been turned on by moving the patient support to a horizontal or neutral Trendelenberg position, further changes in the Trendelenberg position away from horizontal will not disable actuation of the tilt motor.
Referring now to the pitch angle detector 42, the pitch angle sensor 100 produces signals on three outputs, 216, 218 and 220. The sensor 100 produces a pulse train on each of outputs 216 and 218, one lagging and one leading, with one pulse being generated for each degree of movement. As previously indicated, one reference pulse is produced on the third output 220 for each cycle, in this instance, whenever a zero-degree position is being encoded. As previously noted, this zero-degree position is applied to set the input of flip-flop 214 of horizontal pitch detector 98. It, together with the other signals on outputs 216 and 218, are also applied to a direction in zero detect logic circuit 222. This direction and zero detect logic circuit 222 conditions the encoder inputs and determines from the signals in outputs 216 and 218 the direction of the tilt and thus the direction that the decade counter must count. This is indicated to a decade counter 224 by means of a signal applied to a direction input 226 taken from a direction output 228 of direction zero detect logic circuit 222. The decade counter 224 counts pulses from the output 216 applied to its input 230 and counts either up or down depending upon the status of the signal applied to its direction input 226. When a count greater than nine is developed in the decade counter, it causes a pulse to be generated on its carry output 232 which is applied to trigger a carry flip-flop 234 to drive the pitch angle display tens place digit. The units place digit, on the other hand, is driven by a display decoder 236 which receives four binary outputs from decade counter 224 on bus 238 and drives the seven bar segments to make the various decimal representations. Preferably, the Trendelenberg, or pitch angle, does not exceed either positive or negative fifteen degrees with respect to horizontal. The direction and zero detect logic circuit 222 produces a sign signal on an output 238 which is coupled to the pitch angle display 40A to produce a negative sign in the event of the Trendelenberg pitch angle being in a negative direction.
While a preferred embodiment has been disclosed in detail, it should be understood that this has been done to provide an enabling disclosure and that the scope of the invention is not so limited but rather is defined by the following claims. | An electronic controller for a therapeutic table with a shaft encoder for sensing the angular position of a movably mounted patient support and means for controlling the movement in accordance with a comparison between the sensed angular position and an angular limit reference. The left and right preselected tilt angles are alternately automatically selected as the reference. Fault conditions, such as a jam condition, occurs when the drive mechanism to briefly reverse to automatically correct the condition prior to power termination. In the event of excessive tilt, actuation of limit switches results in reversal and movement of the patient support to a horizontal position before power termination. The jam condition is sensed by a strain gauge for detecting the work required for movement of the patient support and comparing it to a preselected work reference. In the event of drive clutch disengagement, power to the motor is terminated. | 0 |
TECHNICAL FIELD OF THE INVENTION AND PROBLEM POSED
The present invention relates to the design and use of energy applicators, and more particularly to resonant cavities and chimney members of shapes and dimensions adapted to the dielectric heating of any compound, regardless of the dielectric constants thereof.
The usual microwave and high-frequency applicators are equipped with traditional chimney members that make it impossible to work at high power density without the risk of electric arcs. The purpose of the chimney members used by the person skilled in the art is aimed at subjecting a product (liquid, solid, gaseous or a mixture of the three states) to electromagnetic waves under static or dynamic conditions, while preventing waves from leaking out of the waveguide. The chimney members, of traditional shape, preferably of cylindrical shape, make it impossible to reach the desired temperature level rapidly and/or to treat a larger quantity of product without the risk of electric arcs. In contrast to polar or polarized molecules, for which energy transfer is optimum, a high power density proves to be necessary to achieve heating of compounds, characterized by low dielectric constants, that absorb electromagnetic waves weakly.
Thus there exists a serious technical problem, posed by the risks of “discharge” or electric arcs and the industrial consequences thereof, which problem represents a major concern in industry, because of the importance of the industrial applications indicated here. By virtue of the invention, the time for processing the products can be very greatly shortened and, in parallel, the industrial efficiency can be improved.
SUMMARY OF THE INVENTION
After numerous attempts, the Applicant has discovered a new shape or geometry for the chimney member, in particular a chimney member of conical shape or geometry, that makes it possible to heat any type of product at microwave frequencies or high frequencies under static or dynamic conditions with a high power density without risk of electric arcs or “discharge”.
APPLICATIONS
The invention makes it possible to achieve heat treatments of compounds that absorb electromagnetic waves weakly in a manner that is just as efficient and rapid as for polar or polarized compounds. The time and energy savings, combined with a lower investment cost, make it possible to ensure that the applications with dielectric heating are faster and more economical.
The invention relates in particular, but non-limitatively, to the treatment of fatty acid esters (unsaturated or otherwise), of hydrocarbons (unsaturated or otherwise), of aromatic compounds and of derivatives of the latter. It is also of great interest, however, for products that strongly absorb electromagnetic waves, because it makes it possible to increase the production capacity of a given system (fatty and non-fatty alcohols, carboxylic acids, amines, etc.).
The present invention relates to all the heating applications involving a single reactant or a mixture of reactants in variable proportions, with or without catalysts, with or without process or “working” gas. Non-limitative examples of heating applications include esterification, transesterification, epoxidation, sulfatization, phosphatization, hydrogenation, peroxidation, isomerization, dehydration, quaternization, amidification, polymerization and polycondensation reactions as well as all the usual treatments such as decolorization, deodorization and the other systems for elimination of volatile compounds.
In fact, the invention is applicable quite particularly to all reactions of “lipochemistry”, and notably has a very strong interest for the case of products that absorb electromagnetic waves weakly.
This innovative technique makes it possible, for example, to synthesize polymers of unsaturated fatty acids, of esters of unsaturated fatty acids, of unsaturated hydrocarbons or of derivatives of such products by means of dielectric heating with microwaves. On this subject the Applicant has filed French Patent Application 98-13770 and PCT Patent Application WO 00/26265 (PCT/FR99/02646).
PRIOR ART
The technical field of the present invention relates to the use of microwave or high-frequency electromagnetic waves both for heating applications on compounds that absorb radiation weakly and on compounds with high dielectric constants.
The microwave (MW) frequencies range between about 300 MHz and about 30 GHz, preferably 915 MHz (authorized frequency with a tolerance of 1.4%) or 2.45 GHz (authorized frequency with a tolerance of 2%).
The high frequencies (HF) range between about 3 MHz and about 300 MHz, preferably 13.56 MHz (authorized frequency with a tolerance of 0.05%) or 27.12 MHz (authorized frequency with a tolerance of 0.6%).
The power (in watts) absorbed by a material under HF or MW treatment is given by the following formula:
Pa=kfε″E 2 V
With:
Pa: power absorbed in W.
E: electric field created in the material in V/cm.
f: frequency of the waves.
K: constant (M.K.S.A)=5.56.10 −13
V: volume of the material in cm 3 .
ε″: material loss factor=ε′ tan δ
ε′: real relative permittivity of the material=ε 0 *ε R
ε 0 : permittivity of vacuum
ε R : dielectric constant
tan δ: loss angle
ε′ represents the tendency of a material to become oriented in the field
and tan δ represents its capacity to dissipate heat.
Remark: for air or vacuum, ε′=1 (which is the lowest value for ε′) and tan δ=0, meaning that ε″=0.
Let us consider a system comprising a guide designed to carry waves corresponding to a given frequency. The product to be heated is placed in a reactor of material that does not absorb the waves (Pyrex, quartz, etc.). This reactor is positioned inside the applicator formed from single-mode cavities that resonate at the emission frequency along a beam in the direction of the waveguide. The microwave applicator is equipped with chimney members, traditionally cylindrical to conform to the shape of the reactor being used (see FIGS. 1 , 2 , 3 ). The purpose of these chimney members is to prevent waves from leaking out of the waveguide. The discharge phenomenon occurs in zones where the tube containing the product to be treated develops disruptive voltages, or in other words where the accumulated energy is such that ionization of the medium (electric spark) occurs. The electric field is characterized by the ratio of the voltage between two points to the distance separating these two points. The risks of discharge occur in the zones where the field is too concentrated.
The reactor can traverse the waveguide at right angles to the direction of propagation of the waves or else parallel to the direction of the waves (see FIGS. 2 and 12 ). The person skilled in the art will understand that these two positions are not the only possible configurations and that the invention encompasses all other intermediate positions.
Reactants:
For the present invention, the reactant or reactants can be chosen from among the products that absorb electromagnetic waves weakly or the products that absorb strongly or a mixture of the two, with or without additions of one or more catalysts or weakly or strongly absorbing additives and/or of process gas.
Among the strongly absorbing products there will be understood fatty or non-fatty alcohols, fatty or non-fatty amines, carboxylic acids, acetals, ketones, enols, peracids, epoxides and, more generally, chemical compounds containing a polar or polarized function, especially
as alcohols: sorbitol, glycerol, mannitol, glycols, vitamins (such as tocopherol, ascorbic acid, retinol), polyphenols, sterols (including the phytosterols) and analogous compounds, and, as amines: ammonia, primary, secondary and tertiary alkylamines (such as methylamine, dimethylamine, trimethylamine, diethylamine), fatty amines (such as oleic amines, alkylamines of coconut oil), aminoalcohols (such as monoethanolamine MEA, diethanolamine DEA, triethanolamine TEA; 3-amino-1,2-propanediol, 1-amino-2-propanol) and ethoxylated amines (2,2′-aminoethoxyethanol; amino-1-methoxy-3-propane).
All of these amines may be saturated or unsaturated, straight-chain or branched.
Among the catalysts or additives there will be understood, as non-limitative examples, the usual acid catalysts (paratoluenesulfonic acid, sulfuric acid, phosphoric acid, perchloric acid, etc.), the usual basic catalysts (sodium hydroxide, potassium hydroxide, alkali metal and alkaline earth alcoholates, sodium acetate, triethylamines, pyridine derivatives, etc.), the acid and/or basic resins of the Amberlite™, Amberlyst™, Purolite™, Dowex™ and Lewatit™ type, zeolites, enzymes, carbon blacks and activated carbon fibers.
Among the weakly absorbing products there will be understood the animal or vegetable oils and fats and the polyterpenes, some of which are derived from the said oils and fats.
Oils or Fats of Animal Origin
As oils or fats of animal origin there can be cited, among others, sperm oil, dolphin oil, whale oil, seal oil, sardine oil, herring oil, shark oil, cod-liver oil, neatsfoot oil and beef, pork, horsemeat and mutton fats (suets).
Oils of Vegetable Origin
As oils of vegetable origin there can be mentioned, among others, rapeseed oil, sunflower-seed oil, peanut oil, olive oil, walnut oil, corn oil, soybean oil, linseed oil, safflower-seed oil, apricot-kernel oil, sweet-almond oil, hemp oil, grape-seed oil, coconut oil, palm oil, cottonseed oil, babassu oil, jojoba oil, sesame oil, argan oil, milk-thistle oil, pumpkin-seed oil, raspberry oil, Karanja oil, Neem oil, poppy-seed oil, Brazil-nut oil, castor oil, dehydrated castor oil, hazelnut oil, wheat-germ oil, borage oil, onager oil, Tung oil and tall oil.
Components of Animal or Vegetable Oils
It is also possible to use components of animal or vegetable oils, such as squalene, which is extracted from the unsaponifiable fractions of vegetable oils (olive oil, peanut oil, rapeseed oil, corn-germ oil, cottonseed oil, linseed oil, wheat-germ oil, rice-bran oil) or contained in large quantity in shark oil.
These oils and fats of animal or vegetable origin as well as the derivatives thereof can be subjected to a preliminary treatment aimed at making them more reactive or, on the other hand, less reactive. The invention relates both to an isolated reactant and to a reaction mixture containing two or more components. These reaction mixtures may contain equivalent proportions of each component, or certain components may predominate.
Unsaturated Hydrocarbons
As unsaturated hydrocarbons there can be cited, as single substances or as mixtures, and as non-limitative examples, an alkene, such as a terpenoid hydrocarbon or hydrocarbons, meaning a polymer or polymers of isoprene, or a polymer or polymers of isobutene, styrene, ethylene, butadiene, isoprene or propene, or a copolymer or copolymers of these alkenes.
Type of Energy Applicator
The choice of energy applicator depends on the technology used (high-frequency or microwave), on the dimensional characteristics of the product to be treated and on the method of treatment thereof.
In the case of polar or polarized molecules, for which energy transfer is optimum, there exists a certain number of standard applicators that have proved their effectiveness.
High-frequency applicators include essentially:
applicators of capacitive type, formed from two capacitor foils between which there is applied the high-frequency voltage of the generator. They are used for heat treatment of materials whose volume comprises a parallelepiped in which one of the sides is sufficiently thick (>10 mm). rod applicators for flat materials, comprising tubular or rod electrodes. They are used for heat treatment of materials whose volume comprises a parallelepiped in which one of the sides is not sufficiently thick (<10 mm). Applicators for thread-like materials, formed of loops.
For the microwave applicators, there can be cited:
localized-field applicators: single-mode cavity diffuse-field applicators: multimode cavity near-field applicators: radiating-antenna guide
In the case of weakly absorbing molecules, the choice of applicators is more complicated. In fact, the applicator must transmit much more electromagnetic energy to the product in order to heat it, while avoiding electric arcs.
Heating at microwave frequencies is preferred to high frequencies, for which the risk of discharge is greater. In fact, the loss factor ε″ and the frequency are lower in this case. For equivalent absorbed power, and in keeping with the formula presented hereinabove, the electric field increases, thus increasing the risk of discharge.
A resonant microwave system is recommended: it may be a localized-field or a diffuse-field applicator. Nevertheless, the “single-mode” system (localized field), which is formed from single-mode cavities resonating at the emission frequency along a beam in the direction of the guide, is preferred to the multimode” system (diffuse field). The single-mode system avoids inhomogeneous distribution of the electric field and the presence of hot spots. Similarly, this type of reactor favors the stability of the exposed products.
The person skilled in the art will understand that dielectric heating of compounds that absorb electromagnetic waves weakly is not limited to the single-mode microwave system. Nevertheless, this system reduces the risk of electric arcs and permits better control of heat treatments.
The chimney members usually used in the single-mode applicators have straight cylindrical shape, in order to conform more closely to the shape of the traditionally used reactors (see FIG. 3 ).
The chimney members are placed on both sides of the waveguide in order to prevent waves from leaking out in the case of tests under dynamic conditions (see FIG. 2 ). The length of each chimney member is determined so as to exclude any leakage of waves and to comply with the safety measures relating to personnel and telecommunications. The French standards are currently identical to the British, German and U.S. standards. These standards are generally less stringent for HF than for MW applications: 10 mW/cm 2 and 5 mW/cm 2 at 1 inch from the equipment. For the usual cylindrical chimney members, the height is related to the material permittivity and reactor diameter by empirical relationships.
For reasons of simplicity and better control of the resonant cavity, the chimney members placed on both sides of the waveguide have identical shape.
The present invention shows that the single-mode applicator equipped with the standard cylindrical chimney members, the most suitable of all standard applicators for weakly absorbing molecules, makes it impossible to work with high power density without the risk of discharge.
An intricate means of alleviating the problems related to weakly absorbing compounds would be to introduce polar compounds such as water into the reaction medium, to act as energy-transfer agent and thus to reduce the necessary power density. This alternative is not satisfactory, however, inasmuch as undesired secondary reactions may occur, and additional treatments such as neutralization, washing, drying or filtration may be necessary to purify the product at the end of reaction.
One alternative for alleviating the problems related to weakly absorbing compounds is to remove the static electricity as soon as it develops on the outside wall of the reactor. For a product that absorbs electromagnetic waves weakly and for a given incident power Pi, the absorbed power Pa decreases and the losses increase, especially those due to static electricity.
In fact:
Pi=Pa +losses
With:
Pi=incident power in W
Pa=absorbed power in W
Losses=heat losses+static electricity
Static electricity is manifested by ionization of molecules of the air. It accumulates on the nonconductive outside walls of the reactor until an electric arc develops. To remove the static electricity, it is necessary either to promote good ventilation by humid air or by another gas having comparable values of dielectric constants (such as sulfur hexafluoride SF6 at 1 bar) (1 st solution), or to adapt the shape of the chimney members in such a way that they are open to the air (2 nd solution). The first solution does not seem advantageous for reasons of installation complexity, safety and cost.
Thus there exists a large and recognized need to improve the known energy applicators, and in particular to adapt them non-limitatively to the field of the process and reactants of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a microwave device according to one embodiment of the present invention;
FIG. 2 is a diagram of a microwave applicator equipped with chimney members according to one embodiment of the present invention;
FIG. 3 is a cross sectional diagram of a chimney member according to one embodiment of the present invention;
FIG. 4 is a cross sectional diagram of a chimney member according to one embodiment of the present invention;
FIG. 5 is a cross sectional diagram of a chimney member and waveguide according to one embodiment of the present invention;
FIG. 6 is a cross sectional diagram of a chimney member and waveguide according to one embodiment of the present invention;
FIG. 7 is a cross sectional diagram of a chimney member according to one embodiment of the present invention;
FIG. 8 is a cross sectional diagram of the reactor traversing the waveguide at right angles in the direction of propagation of the waves according to one embodiment of the present invention;
FIG. 9 shows wavelength characteristics of the configuration depicted in FIG. 8 ;
FIG. 10 shows a configuration of the chimney member, wave guide and reactor according to one embodiment of the present invention;
FIG. 11 shows a configuration of the chimney member, waveguide, reactor and wave-emitting device according to one embodiment of the present invention;
FIG. 12 shows a configuration of the chimney member, waveguide and reactor according to one embodiment of the present invention;
FIG. 13 shows a configuration of the chimney member, waveguide and reactor according to one embodiment of the present invention;
FIG. 14 shows a configuration of the chimney member and waveguide according to one embodiment of the present invention; and
FIG. 15 shows a configuration of the chimney member according to one embodiment of the present invention;
DESCRIPTION OF THE INVENTION
The Applicant has discovered a new shape or geometry for the chimney member, especially a conical chimney member, which makes it possible to heat any type of product at microwave frequencies or high frequencies under static or dynamic conditions at high power density without risk of electric arcs or “discharge”.
More generally, the Applicant has discovered that it is desirable to provide a resonant cavity that extends around the waveguide, for treatment of the product (in other words to create an “additional” resonant cavity around that present in the waveguide), and in particular to provide one or more chimney members around or on each side of the waveguide, preferably with identical geometry and adapted so as to form a resonant cavity extending around the waveguide, for treatment of the product under consideration.
Thus the invention relates in general to an
energy applicator, of the type comprising a waveguide and lateral chimney members, for dielectric heating of any compound, at microwave frequencies or high frequencies, under static or dynamic conditions, at relative power density higher than that of the usual applicators, without risk of electric arcs or “discharge”, regardless of the dielectric constants of the said compound, characterized in that the said applicator is provided with at least one resonant cavity that extends around the waveguide, for treatment of the product.
More particularly, the invention relates to an
energy applicator, of the type comprising a waveguide and lateral chimney members, for dielectric heating of any compound, at microwave frequencies or high frequencies, under static or dynamic conditions, at relative power density higher than that of the usual applicators, without risk of electric arcs or “discharge”, regardless of the dielectric constants of the said compound, characterized in that the said applicator is provided with at least one chimney member of geometry adapted to form a resonant cavity around the waveguide, for treatment of the product under consideration, applicator such as described in the foregoing, characterized in that this cavity is formed on each side of the waveguide, applicator such as described in the foregoing, characterized in that this cavity is formed around the waveguide by one or more chimney members, applicator such as described in the foregoing, characterized in that the chimney member or chimney members is or are placed on each side of the waveguide, around the resonant cavity, applicator such as described in the foregoing, characterized in that the chimney members are of identical geometry.
In this context it will be noted that the geometries to be described reflect the surprising concept that it is possible to work usefully (meaning to treat the product) in a zone larger than that recognized unanimously in the prior art, or in other words a zone in which the constant prior art was careful not to work. The discovery of this principle has made it possible on the one hand to create new and original geometries, avoiding discharge, which was the first objective, and on the other hand to obtain, completely unexpectedly, a substantial savings in treatment time and investment costs. It has been demonstrated in a test that the time for treatment of 60 ml of product in the “zone” or cavity enlarged according to the invention was equal to the treatment time necessary for treatment of 33 ml of product in a crucible.
The uniqueness of these new chimney members derives from their shape. They are composed of two main portions: an upper portion, which must be as close as possible to the reactor in order to prevent waves from leaking out, and a lower portion whose shape flares toward the waveguide so that, according to the invention, electric arcs are reduced and the additional resonant cavity mentioned hereinabove is created around the waveguide.
The person skilled in the art will understand that the shape and dimensions of the said additional cavity around the waveguide, or in other words around the resonant cavity normally already present in the waveguide (which cavity is strictly limited in the prior art), can be entirely varied as a function of the envisioned application and of the apparatus.
In particular, there can be cited the symmetric shapes, and in particular the shapes composed of at least a conical base, a spherical shape or a shape of ellipsoidal or analogous volume, the broadest portion opening into the waveguide in all cases.
The upper portion of these new chimney members must be as close as possible to the reactor in order to prevent leakage of waves. This portion may have diverse shapes, such as cylindrical shapes with circular, rectangular or square cross section, without being limited thereto. It may also include a plurality of successive different shapes. Nevertheless, the most commonly used shape is the cylindrical shape with circular cross section, in order to conform best to the shape of the reactor and to avoid the presence of edges, which favor electric arcs. The height of this portion of the chimney member is determined from the viewpoint of excluding any leakage of waves.
The person skilled in the art will understand that this upper portion does not necessarily have to be present in the case of completely shielded systems. In this type of configuration, the problem of waves leaking out is effectively suppressed, because the entire system then represents a resonant cavity.
The lower portion of these chimney members must be of flared shape, in order to prevent electric arcs at the waveguide. For this purpose there can be cited, as non-limitative examples, the conical and/or spherical shapes having variable angles relative to the vertical, and the pyramidal shapes having square or rectangular bases. As in the foregoing, this portion of the chimney member may have a combination of these different shapes. The main parameter that must be taken into account is the base diameter of these flared shapes: it must not exceed the width of the waveguide. Once the diameter has been chosen, the height and apex angle of the flared portion are fixed as a function of the power used.
In the case of single-mode microwave applicators at 2450 MHz, the recommended waveguide width for remaining in TE 0.1 mode (transverse electric) ranges between approximately 70 and 100 mm. The TE 0.1 fundamental mode of excitation permits the wave to propagate along a single arc.
At less than 70 mm, the wave does not propagate (cutoff frequency).
At greater than 100 mm, the mode changes to TE 0.2, with two field maxima, implying less homogeneous heating.
The person skilled in the art will understand that the invention is also applicable at other microwave frequencies and high frequencies, and that similar reasoning can be advanced for all of these frequencies.
Although all geometric shapes and combinations thereof can be envisioned, it is advisable for reasons of simplicity and cost to work preferably with chimney members of identical shapes and dimensions on both sides of the waveguide and also with a minimum of combinations for each.
The invention will be more clearly understood by reading the description to follow and the non-limitative examples below.
In the attached FIGS. 1 to 15 , the symbols have the following meanings:
MW milliwattmeter SR′ cooling system I iris (a kind of adjustable diaphragm) AP applicator with chimney member or chimney members P short-circuit piston BC double coupler SA automatic stub system (insertable movable screws) C safety device (circulator) SR cooling systems TMO microwave head G magnetron generator GO waveguide R reactor exposed to waves CH chimney member or chimney members PS upper portion of chimney member Pi lower portion of chimney member V 1 , V 2 , V 3 , V 4 volumes ( FIG. 15 )
EXAMPLES
The examples below illustrate the interest of the invention as well as of its variants, and will permit the person skilled in the art easily to extrapolate to other dimensions and/or geometries without departing from the scope of the invention.
The following examples, which are in no way limitative, illustrate the merit of the invention. They are intended to demonstrate that the usual microwave and high-frequency applicators are not adapted to all products, and more particularly to weakly absorbing products. To be able to heat these products without risk of discharge, it is advisable to modify the shape of the chimney member of these applicators.
The examples also demonstrate the successive difficulties encountered in the development of the present invention.
I—Appliances Used
The microwave device comprises different elements:
(see FIG. 1 )
The microwave system is composed of a magnetron generator G operating at the frequency of 2450 MHz (λ=12 cm) at a power ranging up to 6 kW. The generator transmits the energy to the microwave head TMO, which will transform the high voltages comprising the energy to microwaves. The circulator C is a safety device, which allows the incident waves to pass and redirects the reflected waves to a water ballast, where the waves are absorbed, thus raising the water temperature. The double coupler BC makes it possible to know the reflected and incident powers by virtue of the milliwattmeter MW. The automatic stub system SA is composed of 4 insertable screws in the waveguide for the purpose of attenuating the reflected power of the system. The iris I and the short-circuit piston P make it possible to adapt the microwave system to the substance to be treated. In other words, to favor better absorption by the substance of the power emitted by the generator, the electric field must be maximal at the location of the solution, which can be achieved by appropriate adjustment of these two elements. The system is equipped with two cooling systems SR in order to prevent any overheating. The substance is placed in the applicator AP, formed by single-mode cavities resonating at the emission frequency along a beam in the direction of the guide.
The pilot is adapted to the microwave system. It comprises the microwave reactor, positioned in the field of the waveguide. The tests can be performed under static or dynamic conditions.
II—Results:
The tests were performed by means of a 6-kW magnetron generator operating at the frequency of 2450 MHz. The single-mode applicator was constructed on the basis of a rectangular waveguide of 86 mm width and 43 mm height. In this type of applicator, the distribution of the electric field is localized and the Pyrex™ reactor is placed in maximum interaction therewith by virtue of a short-circuit piston. An impedance-matching device, placed between the generator and the applicator, also assures the adjustments necessary for optimal transfer of energy into the product to be treated.
The tests were performed under static and dynamic conditions.
Two types of chimney members CH were tested on two types of products:
standard cylindrical chimney members (see FIG. 3 ) conical chimney members (see FIG. 4 )
and
water: polar molecule with good dielectric characteristics rapeseed oil: molecule with poor dielectric characteristics
The values of the dielectric characteristics of these products are presented in the table below:
Relative
permittivity ε′
Loss factor ε″
Loss angle tan δ
Water
80
20
0.25
Rapeseed oil
4.5
0.2
0.044
The experiments performed on 1.5 kg of product demonstrate the efficacy of these new chimney members:
Tested Chimney member power Water Rapeseed oil Standard (cylindrical) 2 kW no arcs arcs in 10 min Conical (invention) 4 kW no arcs no arcs
III—Tests Performed
All tests were performed with rapeseed oil.
a—Test with Two Standard Chimney Members (Prior Art) of 95 and 65 mm Heights and a Microwave Reactor of 30 mm Diameter.
See FIG. 5
The test was performed on rapeseed oil with a microwave tube having an inside diameter of 30 mm and a height of 1 m.
P reflected
Leaks
P emitted (kW)
(W)
(mW/cm 2 )
Remarks
0.5
160
0 to 0.2
1
279
0.3
2
600
0.4
Arcs,
glass deformed
At the moment when arcs began, the temperature was 240° C. The arcs did no break the glass, but deformed it. The strike occurred just at the beginning of the upper chimney member.
see FIG. 6
The places of the reactor that are most susceptible to arcs are those where the distance between waveguide and chimney member of the reactor is shortest. See FIG. 7
These arcs are caused by the fact that the electric field is too strong. Attempts were then made to increase the volume of product exposed to the field.
b—Chance of Configuration
The waveguide was modified in such a way as to expose a larger volume to the field.
Old Configuration
In the old configuration, the reactor traversed the waveguide at right angles to the direction of propagation of the waves.
See FIG. 8
See FIGS. 9 and 10
Total length=77.86 cm
Since λg/2=8.66
then 8 (λg/2)=69.28 and
9 (λg2)=77.94
9 half-periods are counted between the iris and the piston
New Configuration
In the new configuration, the reactor traverses the waveguide parallel to the direction of propagation of the waves.
See FIGS. 11 and 12
Total length=63 cm
7 (λg/2)=60.62
8 (λg2)=69.28
Slightly more than 7 half-periods are counted between the iris and the piston.
The reactor was filled with rapeseed oil and power tests were performed.
At 5 kW, an arc developed in 5 minutes. At 2 kW, it appeared at the end of 36 minutes. In both cases, the temperature attained did not exceed the desired temperature level.
Once again, a single arc strike occurred at the junction between the chimney member of the reactor and the waveguide:
See FIG. 13
To limit the presence of electric arcs, it must therefore be ensured that the reactor is not too close to the waveguide.
The old configuration (vertical arrangement) achieved better results. The next tests were performed with this first configuration but with new shapes of chimney members.
c—Use of Conical Chimney Members
Two criteria must be taken into account:
1—the volume exposed to the field 2—the distance between the reactor and the waveguide constituted by the chimney member
New chimney members are designed to meet these two criteria. They are characterized as conical. More precisely, they comprise a standard cylindrical portion and a conical portion at the level of the waveguide. They replace the straight cylindrical chimney members.
See FIGS. 3 and 4
The microwave reactors can then have different shapes:
See FIGS. 14 and 15
With approximately:
V 1=4.33 *Π*x 2 /4
V 2=9.95*Π*3 2 /4=70.33 cm 2
V 3+ V 4 =9.95*Π*( x −3) 2 /4
For x=3 cm, Vtotal=171.2 cm 2
For x=5 cm, Vtotal=282 cm 2
For x=6 cm, Vtotal=394.3 cm 2
Power tests at 4 kW were performed on reactors of 50 mm (x=5 cm) and 30 mm (x=3 cm) diameter.
With the 50-mm reactor, an arc developed at the end of 6 minutes. The reactor was too close to the waveguide.
In contrast, with the reactor having 30 mm diameter (straight reactor), no arc developed. The only arcs that can occur were observed when the reactor was weakly centered.
d—Ventilation by Humid Air
Additional tests were performed to optimize the results obtained with these new chimney members a little more.
The tests were performed with the conical chimney members and a straight reactor of 30 mm diameter (better conditions, see II-c).
To remove the static electricity, it is necessary to promote good ventilation by humid air or by another gas having comparable values of dielectric constants (example: SF6 at 1 bar). In the present case, water vapor was injected at the applicator. To prevent water from condensing on the reactor walls, it was necessary to add suction at the outlet of the chimney members.
With gentle suction, an arc developed at 282° C. and Pi=5 kW.
With very strong suction, an arc developed at 284° C. and Pi=6 kW. At 5 kW, however, no arc developed.
Ventilating with humid air therefore improves the results. Nevertheless, the ventilation must be sufficiently intensive to achieve a real effect.
Conclusions of the Tests:
The tests performed at 2450 MHz show that the system of chimney members in “conical” shape then makes it possible to avoid electric arcs at high emitted power (4 kW, instead of 2 kW with the standard chimney members). During operation at such powers, the desired temperature level (up to 400° C.) is reached very rapidly, or in other words in less than 15 minutes for the treatment of 1 kg of product.
It will be entirely preferable, without being limitative, to use the dimensions and shapes illustrated in FIG. 4 , which represents the best embodiment of the invention to date. As is evident, a chimney member having a conical lower portion and a cylindrical upper portion is used in this case.
The invention also covers all the embodiments and all the applications that will be directly accessible to the person skilled in the art from reading this application, from his own knowledge and possibly from simple routine tests. | A dielectric heating system with which the power density applied to the product being treated can be at least doubled without risk of electric arcs. This invention is particularly suitable for treatment of compounds that absorb electromagnetic waves weakly (low dielectric constants). In particular, fatty substances such as oils, butters, waxes and fats can be treated (refining, hydrolysis, transesterification, interesterification, etc.), derivatives thereof (esterification, polymerization, alcoholysis, ethoxylation, hydrogenation, etc.) under static or dynamic conditions, as can hydrocarbons and aromatic compounds. This system can also be used advantageously for polar or polarized compounds, because the power absorbed is increased very significantly, with large production gains. In particular, fatty or non-fatty alcohols (oleic alcohol, glycol, glycerol, mannitol, sorbitol, polyglycerols, vitamins, etc.), carboxylic acids, amines and similar compounds can be treated under static or dynamic conditions. | 7 |
BACKGROUND OF THE INVENTION
The invention relates to a method for laser drilling holes in a substrate, in particular an electrical circuit substrate, the laser beam with a spot diameter smaller than the hole diameter to be drilled being moved along at least one circular path in the region of the hole to be drilled in each case.
U.S. Pat. No. 5,593,606 discloses a method of this kind whereby holes with a diameter larger than the beam diameter of the laser are produced by moving the laser beam outward or inward either along spiral paths or in concentric circles within the hole region.
For the drilling of circuit boards or comparable circuit substrates, after optimization the particular deflector unit used is moved to one hole position after another, the shape and processing or machining of the hole being expediently predefined by a program (a so-called drilling tool). Using this program each hole is machined in an identical manner. In a suitable procedure, for particularly precise and rapid drilling the laser beam is programmed to jump from an initial position, e.g. a previously drilled hole, to the center of the new hole to be drilled and is traversed from there to the first circular path in an always identical, defined angular direction. After completing this first circular path, the beam can then, if necessary, be traversed to other circular paths. If the traversing direction from the hole center to the first circular path is now fixed at a predefined angle, whereas the previous jump direction from different starting points (drilled holes) assumes quite different angles in each case, this means that for the majority of all holes a change of direction of up to 180° is necessary between the jump to the hole center and the traversing movement to the circular path. The larger this change of direction between the jump direction and the traversing direction, the greater the necessary abrupt change in position of the deflector unit also, i.e. in general the galvo mirrors. An angular change of direction always means a time loss due to the necessary recovery time of the mirrors after the movement as well as a stress factor for the galvo motors because higher peak currents are flowing; this has a negative effect on their service life. If a mirror recovery time is dispensed with, this adversely affects hole quality, i.e. non-circular holes are obtained. In addition, particularly in the case of a 180° reversal in the direction of travel, it is first necessary to stop, and then re-accelerate, which means that a new galvo motor lag error is introduced.
SUMMARY OF THE INVENTION
The object of the present invention is to improve the above-mentioned method for drilling holes in substrates in such a way that a higher process speed is achieved while maintaining good hole quality, i.e. good hole circularity. At the same time the deflector units should be less stressed, i.e. so that galvo motors in particular achieve a longer service life.
This object is achieved according to the invention as follows: each time the laser beam is aligned to a new hole, the beam axis is first directed to the center of the hole to be drilled in a jump direction predefined by the beam position and then directed away from the center in a defined radial traversing movement onto a defined circular path, the angular direction of the traversing movement being defined as a function of the jump direction in such a way that a change in direction of the beam axis at the center does not exceed a predefined maximum angular range or that—ideally—the direction is maintained.
With the method according to the invention, the movement away from the hole center is therefore selected as a function of the jump direction from the last hole in each case in such a way that abrupt changes of direction, e.g. of more than 225°, are avoided.
In a first embodiment of the method according to the invention, this can be achieved by varying the predefined drilling program for a hole in each individual case so that the angular direction of the traversing movement is matched to the jump direction of the incoming laser beam. Although in this case there is now no or virtually no change in direction at the hole center, a solution of this kind is very costly.
For the majority of applications, an advantageous embodiment of the method according to the invention is therefore one in which a number of angular directions, each assigned an angular range for incoming jump directions, are predefined for the traversing movement according to the predefined maximum angular range, an associated drilling program with the associated traversing direction being selectable depending on the angular range in which the jump direction lies. If, for example, the maximum permissible angular range for a change of direction at the center is 45°, eight angular ranges of 45° to which an outgoing traversing direction with associated drilling program is assigned in each case are specified for the incoming jump directions. The associated drilling program is then selected and implemented depending on the jump direction of the incoming laser beam.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The invention will now be explained in greater detail with reference to examples and the accompanying drawings in which:
FIG. 1 schematically illustrates a laser arrangement for drilling holes in a multilayer substrate,
FIG. 2 shows the path of the beam axis of an incoming laser beam in the region of a hole to be drilled, without angular change at the center,
FIG. 3 shows the path of the incoming laser beam in the region of a hole to be drilled, with maximum angular change at the center,
FIGS. 4 to 11 show the path of the axis of a laser beam in the region of a hole to be drilled using the method according to the invention for different jump directions of the incoming beam.
DETAILED DESCRIPTION OF THE INVENTION
The arrangement shown schematically and not drawn to scale in FIG. 1 shows a laser 1 with a deflector unit 2 and an optical imaging unit 3 via which a laser beam 4 is directed onto a substrate 10 , preferably a circuit board. In the example shown, this substrate 10 has an upper first metal layer (e.g. a copper layer) 11 and a lower second metal layer 12 between which a dielectric layer 13 is disposed. This dielectric layer consists, for example, of a polymer material such as RCC or a woven glass reinforced polymer material such as FR4. It is well known that the metal layers which generally consist of copper require a different amount of energy for processing or transmission than the dielectric. Accordingly, different laser settings as well as different pulse repetition rates and different focusings of the laser beam can also be selected.
As shown in FIG. 1 , blind or through via-holes 15 with a diameter D 1 are to be drilled into the substrate 1 . For this purpose, holes 14 can be drilled through the copper layer 11 , for example, with a first setting of the laser and then the blind vias 15 can be made in the dielectric layer 13 using another laser setting. Irrespective of which material is being drilled, it will be assumed here that the laser beam 4 is moved with its focal point F 1 in concentric circles in the hole region to be drilled until the material has been completely removed from the relevant hole 14 or 15 . The individual holes are processed one after the other, so that the laser beam or the optical axis of the laser beam which has been deactivated or operated with very low energy during the jump (at 355 nm UV e.g. in CW mode) jumps from one hole region to the next.
In FIG. 1 this jump direction from one hole to the other is indicated by an arrow S in each case. The jump therefore proceeds from a starting point at a previous hole, e.g. after completion of a drilling operation at a peripheral point or hole center, in an approximately straight line to the center of the subsequent hole to be drilled. From this center M a predefined drilling program is initiated, the axis of the laser beam being first directed onto a circular path in a fixed traversing direction V or alternatively starting from the center of the circle. When the circular path is reached, the laser is activated and the laser beam travels around the circular path in one or more passes depending on the particular requirements, such as substrate material, hole depth, type and energy density of the laser. If the size of the hole requires a plurality of concentric passes of the laser, after traveling around the first circular path one or more times the laser beam is traversed to another circular path. In practice the laser beam or the beam axis of the deactivated laser is moved from the center M in the traversing direction V only initially, after which it is expediently controlled in such a way that it is brought progressively closer to the desired circular path K, describing an arc B ( FIG. 2 ).
As mentioned, the angle of the jump direction S to the center M depends on the relevant starting point A, which is generally a previously drilled hole. Depending on the arrangement and sequence of the holes to be processed, the jump direction S can therefore assume any angle. However, as the angle of the traversing direction V is pre-programmed in a fixed manner, a more or less large change of angle occurs at the center M. The ideal case is shown in FIG. 2 , in which the starting point A is located such that the jump direction S is approximately the same as the traversing direction V which is assumed to 0° in the X-axis. The axis of the laser beam can therefore be moved further away from the center M without discontinuity, so that the deflector unit can execute a continuous movement. The laser beam is therefore moved in the traversing direction V toward the circular path, then brought into the circular path K following the dashed arc B or alternatively in the traversing direction V and performs the drilling operation along the dashed circular path K.
The worst-case scenario for guiding the laser beam is shown in FIG. 3 . In this case the axis of the laser beam arrives in a jump direction which is at an angle of 180° to the predefined traversing direction V. The beam axis therefore has to accomplish a 180° direction reversal at the center M. To achieve this, the deflector unit first has to be stopped and then accelerated in the new direction.
In order to avoid such delays caused by large changes in direction at the center of the hole to be drilled, the traversing direction is matched as closely as possible to the jump direction S in terms of angle in accordance with the invention. As any adaptation of the drilling program in order to achieve the ideal case (in accordance with FIG. 2 ) for each direction is very complex/costly, a certain number of drilling programs is rigidly predefined, and, depending on the jump direction, the program having the smallest deviation between jump direction and traversing direction is selected in each case. In the example described here, eight programs having traversing directions V 1 to V 8 each offset by 45° are predefined, each traversing direction being assigned an angular range for an incoming jump direction. These eight predefined combinations of jump direction and traversing direction are shown in FIGS. 4 to 11 . The eight pre-programmed traversing directions V 1 to V 8 are each linked to an angular range W 1 to W 8 so that, depending on the angular range W 1 to W 8 in which a jump direction S 1 to S 8 falls, the associated drilling program is automatically initiated with traversing direction S 1 to S 8 , resulting in a maximum angular change at the center of 22.5° between jump direction and traversing direction. The direction from the hole center is given by the bisector of the opposite incident angular range in each case. If this angular range is 45°, the maximum angular change per range is max. 22.5° (see FIG. 4 ).
As the positions and machining sequence of the holes to the drilled on the substrate or circuit board are generally known, the relevant drilling program can be defined in advance for each hole to be the drilled so that no time losses due to any lack of processor power can occur. Moreover, the number of specified traversing directions is in no way limited to the example described, but any other number of predefined traversing directions and associated drilling programs can be provided depending on requirements or, ideally, the direction can be taken into account online. | Disclosed is a valve having a housing with a valve seat for a two-piece flap which is rotatably mounted on a drive shaft. An annular piston seal and an adjacent cover disk are disposed between the first part and the second part of the two-piece flap so as to revolve therearound. The diameter of the cover disk is smaller than the diameter of the annular piston seal which is embodied as a metal ring that is provided with a gap. The invention also relates to the use of the valve as a gas recirculation valve. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to a device for securing railroad rails on a ballast track or a solid track in a highly resilient manner.
Two separate systems exist as devices for securing railroad rails. On the one hand, the attachments for sleepers or supports on a ballast foundation, and on the other hand the superstructure for a solid track, i.e. securing rails for a superstructure without ballast. The superstructure on a solid track is increasingly gaining in important as axle loads and journey speeds rise, whereby as regards the superstructure on a solid track it is essential to achieve a requisite track compression.
Yet ballast tracks which are fitted with the standard superstructure also frequently exhibit rail compression values that are too low for use in high-speed transport on new routes. The resilience of ballast permits track compression which results in a rail head depression of about 0.6 mm. This track compression is clearly below today's desired rail head depression of 1.5 mm.
The resilient intermediate layers used in the prior art, even the use of so-called “soft” intermediate layers with static spring rates of c=50-70 kN/mm, improve track compression only to a rail head depression of about 1.0 mm (in conjunction with the ballast track).
A device for securing railroad rails on a solid track is described in EP 0 295 685. To achieve good track compression, a resilient intermediate plate is disposed between the rail flange and the concrete railroad sleeper; this plate ensures sufficient compression. Above the resilient intermediate plate there is located a pressure distribution plate which is dimensioned such that it and the resilient intermediate plate laterally project above the flange of the rail. Angle guide plates which form a support for tension clamps to secure the rails and which press the same against the rail flange by means of a sleeper screw are arranged on both sides of the rail flange. The guide angle plates form a rail channel, absorb the horizontal forces and introduce them into the concrete sleeper via angled surfaces in contact with the sleeper. The angle guide plates have chamber-like recesses into which the pressure distribution plate (protruding on both sides across the width of the rail flange) and resilient intermediate plate can project. The concrete sleepers described in EP 0 295 685 are specifically adapted to use on a solid track, and in the securing region they have a very low recess that completely receives the angle guide plates.
SUMMARY OF THE INVENTION
The present invention is based on the object of using standard elements and standard concrete sleepers to design a rail attachment, by means of which high rail compression values can be achieved.
The device for securing railroad rails on a ballast track or a solid track includes a standard concrete sleeper used on the ballast track; two angle guide plates for a securing point of the railroad track on the standard concrete sleeper, the plates being arranged on both sides of the rail flange for lateral guidance thereof; one securing screw per angle guide plate, the screw passing though the plate and pressing a tensible clamp against the rail flange and pressing the rail flange and the angle guide plate against the standard concrete sleeper; at least one resilient intermediate plate arranged between the rail flange and the standard concrete sleeper; wherein the angle guide plates have a first and a second surface at their end facing away from the rail, the first surface being inclined at an angle to the perpendicular in the mounted position and abutting a correspondingly shaped angled surface of the standard concrete sleeper, and the second surface being essentially vertically aligned and rising over the upper side of the standard concrete sleeper.
By using angle guide plates which can be inserted almost completely into the concrete sleeper's depression, not only a resilient intermediate plate but also a pressure distribution plate and a plastic intermediate layer can be arranged between rail and concrete sleeper despite the use of standard concrete sleepers, with it being possible nevertheless to use a standard tension clamp.
By providing the angle guide plates with receiving spaces which are each open toward the rail flange in the mounted position, the resilient intermediate plate can protrude on both sides across the width of the rail flange and project into the receiving spaces of the angle guide plates arranged on both sides of the rail.
Both the resilient intermediate plate and the pressure distribution plate advantageously have a larger extension in the standard concrete sleeper's longitudinal direction than the rail flange and therefore protrude across the width of the rail flange on both sides thereof and project into the receiving spaces of the angle guide plates. As a result, the pressure distribution plate distributes over a large surface area the forces transferred by the rail flange to this plate and introduces them evenly into the standard concrete sleeper via the resilient intermediate plate. This embodiment also enjoys the advantage that when the pre-assembled securing devices are delivered on the sleeper, the resilient intermediate plate and the pressure distribution plate are undetachably arranged between the two angle guide plates which form a securing point.
The securing screws are preferably anchored in interchangeable plastic screw dowels located in the standard concrete sleepers. This makes it possible on the one hand to perform quickly any necessary maintenance work that requires the screw dowel to be exchanged, and on the other hand to allow the use of various standard tension clamps and to adapt quickly and reliably the concrete sleeper to the particular sleeper screws used for this purpose.
According to a preferred embodiment, the shape of the angle guide plates is adapted to the use of a standard tension clamp for securing the rail flange, as described e.g. in DE 39 18 091. It is therefore possible to fall back on a maximum number of standard elements and perhaps to perform conversion of existing track installations without changing the tension clamps.
Different angle guide plates which in their mounted position have a varying horizontal extension in the standard concrete sleeper's longitudinal direction can be preferably used. As a result, the position of the rail channel formed between two angle guide plates is variably designed and the gauge can be set or corrected within predetermined limits.
The rotational axes of the securing screws are preferably inclined at an angle to the perpendicular. This makes it much easier to place the rail into the rail channel formed between the angle guide plates.
BRIEF DESCRIPTION OF THE DRAWING
The FIGURE shows a cross-section through a symmetrical device for securing a rail according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The drawing shows a cross section through a symmetrical device 10 for securing a rail 12 . The rail 12 together with a second rail 12 forms a railroad track. The device 10 serves to tension the flange 14 of the rail against a support 16 which in its longitudinal extension runs transverse to the longitudinal direction of the rail 12 .
The support 16 preferably consists of concrete and represents for example a standard concrete sleeper, as used by the German railroad company Deutsche Bahn AG with the designation DB Standard Concrete Sleeper B70 W60. This standard concrete sleeper has so far been used in the ballast superstructure, but not on a solid track.
In the region in which one rail 12 of the rail pair is respectively received, the standard concrete sleeper 16 , henceforth abbreviated to concrete sleeper, has a depression 18 that runs perpendicular to the longitudinal sleeper axis and is composed of a planar support surface 20 and groove-like depressions 22 . The groove-like depressions pass in the longitudinal direction of the rail 12 and extend across the entire sleeper width or part thereof. The groove-like depression 22 has an angled surface 24 on the side that faces away from the rail 12 .
A plastic dowel ( 60 , see FIGURE), the longitudinal axis 26 of which is inclined with respect to the perpendicular in the mounted position, is also located in the concrete sleeper 16 for each securing device 10 in the region of the planar receiving surface 20 . The angle to the perpendicular is about 5° in the illustrated exemplary embodiment.
An angle guide plate 30 , which with the angle guide plate on the other side of the rail forms an exact rail channel, is respectively at the side of the rail flange 14 and is both supported on the planar receiving surface 20 and inserted into the groove-like depression 22 . The angle guide plates also serve to remove horizontal forces and to receive a rail attachment that can be pre-assembled.
The angle guide plate 30 has a guide surface 32 for the rail flange 14 ; in its mounting position, this guide surface is preferably spaced a minimal distance away from the facing side of the rail flange 14 . This makes it possible to obtain a rail head depression, as is required in the form of a predetermined rail compression value. The angle guide plate 30 's side that is at the to in the mounting position and which faces toward a tension clamp 34 is adapted to the shape and function of the particular tension clamp 34 used. In the present example, the angle guide plate has a guide channel 36 for receiving a rear support curve of the tension clamp 34 , a bore 38 for a sleeper screw 40 and a guide channel 42 for the inner shank of the tension clamp 34 . On the side facing the concrete sleeper 16 in the mounted position, the angle guide plate 30 is shaped to correspond to the concrete sleeper. The angled surface 44 of the angle guide plate 30 is shaped such that contact is made as completely as possible with the angled surface 24 of the concrete sleeper and hence any horizontal forces that arise can be removed as evenly as possible into the concrete sleeper. Support elements 46 are formed in the region of the concrete sleeper's planar receiving surface 20 ; the vertical forces which arise during tightening of the tension clamp 34 are transferred to the concrete sleeper 16 by these elements.
The angle guide plate 30 has, toward the rail 12 , a U-shaped profile parallel to the longitudinal rail axis when viewed in vertical section and whose shanks are formed by the support elements 46 . As a result, a chamber-like receiving space 48 is obtained between the planar receiving surface 20 of the concrete sleeper and the transverse element of the U-shaped profile on the one hand and between the two support elements 46 on the other. This receiving space serves to accommodate the following elements arranged between the underside 50 of the rail 12 and the planar receiving surface 20 .
An essentially vertical, outer terminating surface 28 that projects above the upper side 29 of the concrete sleeper 16 beyond the depression 18 adjoins the angled surface 44 at that end of the angle guide plate 30 which points away from the rail 12 . As shown in the drawing, surface 28 has a linear aspect forming an angle with a linear aspect of surface 44 .
To achieve a required rail head depression both in the case of a solid track and on a ballast track, the resilience of which permits a rail head depression of only about 0.6 mm, a resilient intermediate plate 52 is placed on the concrete sleeper's planar receiving surface 20 and hence is placed between the rail's underside 50 and the concrete sleeper. The resilient intermediate plate 52 is composed of an elastomer and has a static spring rate that is adjustable in accordance with requirements.
A pressure distribution plate 54 which is planar and can be easily produced in rolled steel is placed over the resilient intermediate plate 52 . The pressure distribution plate 54 and the resilient intermediate plate 52 have an extension in the concrete sleeper's longitudinal direction that is larger than the width of the rail 12 at the underside 50 thereof. As a result, the pressure distribution plate 54 and the resilient intermediate plate 52 each laterally project over the flange 14 of the rail.
The resilient intermediate plate 52 and pressure distribution plate 54 protrude into the chamber-like receiving spaces 48 of the angle guide plates 30 arranged on both sides of the rail and are each provided with a slot oriented in the longitudinal sleeper axis. The resilient intermediate plate 52 and pressure distribution plate 54 preferably make form-locked contact with the receiving space 48 's longitudinal walls that run in the longitudinal direction of the concrete sleeper. The clearance of the receiving space 48 is dimensioned to be larger than the total thickness of resilient intermediate plate 52 and pressure distribution plate 54 , thus essentially preventing the end sections of the plates 52 and 54 from pressing together when the angle guide plates 30 are pressed down onto the concrete sleeper 16 . The force applied by the tension clamp 34 is essentially transferred directly to the concrete sleeper 16 via the angle guide plate, which causes the rail's angle of inclination to keep to the required accuracy even if the two tension clamps of a securing point are perhaps unevenly pre-tensioned.
The highly resilient intermediate plate 52 allows the rail to exhibit the necessary vertical depression and can be selected such that the rail's desired compression is achieved. The steel pressure distribution plate 54 evenly distributes over a large surface area those vertical forces which act upon the rail. The pressure distribution plate 54 therefore acts as an artificial enlargement of the rail flange.
A plastic intermediate layer 56 is also disposed between pressure distribution plate 54 and the underside 50 of the rail 12 .
Various tension clamps 34 and sleeper screws 40 known in the prior art can be used in the device 10 for securing railroad rails on a ballast track or on a solid track. In the present example, the rail is tensioned with the resilient tension clamp SKL 14 common in the ballast superstructure. The two free spring arms 58 of the tension clamp 34 are supported on the rail flange. A center loop that prevents tilting also projects over the rail flange. The rail is vertically tensioned by tightening the sleeper screw 40 anchored in interchangeable plastic screw dowels. After tightening the tension screw 40 , the two free spring arms 58 of the tension clamp 34 exert a force of about 2×10 kN on the rail in the case of a resilient spring path of approx. 13 mm.
The rail attachment can be pre-mounted on the sleeper and then delivered. For this purpose, the tension clamps are in a pre-assembly position which is shown in the aforementioned DE 39 18 091 for the SKL 14 tension clamp depicted in the drawing. The sleeper screw 40 is screwed into the plastic dowels only by a few turns and enables the tension clamp 34 to be pre-mounted by being shifted to the left with respect to the mounting position shown in the drawing, i.e. it is moved away from the site where the rail is subsequently fitted only. To do so, the tension clamp 34 is no longer located in the guide channel 36 of the angle guide plate 30 .
The tension clamp 34 and the angle guide plate 30 on the one hand, as well as the resilient intermediate plate 52 and the pressure distribution plate 54 on the concrete sleeper 16 on the other are fixed into the mounting position via the sleeper screw 40 . When mounting the rails, only the plastic intermediate layer 56 has to be interposed between the underside 50 of the rail 12 and the pressure distribution plate 54 , the tension clamp 34 shifted in the rail flange's direction so that the free spring arms 58 are supported on the rail flange 14 , and the sleeper screw 40 finally tightened.
In the mounted state, the angle guide plates 30 arranged on both sides of the rail 12 form a rail channel, and remove the horizontal forces into the concrete sleeper 16 via the contact of the angled surfaces 44 and 24 . Part of the horizontal forces that arise are also introduced into the concrete sleeper by the axes 26 —inclined at an angle to the perpendicular—of the sleeper screws 40 .
The securing system 10 is designed to make height regulation possible up to 5 mm without tamping work. If desired, gauge regulation of up to ±10 mm can also be performed by using specially shaped angle guide plates 30 whose interaction on both sides of the rail 12 systematically shifts the rail channel in the longitudinal direction of the concrete sleeper 16 .
Since the resilient intermediate plate 52 permits the required high rail compression in the form of a predetermined rail head depression of about 1.5 mm, the described rail attachment is also suitable for the use of high-speed trains on new routes. It is therefore possible to convert an existing ballast track to the securing system according to the invention by continuing to use standard concrete sleepers, which also makes this system suitable for use in high speed transport.
It is also possible to fill up the cavities of the ballast track with concrete, asphalt of the like and therefore to continue using this securing system on a solid track without changing the system because the manner of securing rails according to the invention achieves the desired high compression values as regards overall resilience even without the ballast foundation's contribution. | A device for securing railway rails ( 12 ) on a solid track includes a standard concrete sleeper ( 16 ) used for the ballast track. Each of the rails ( 12 ) is guided between two angle guide plates ( 30 ) and urged by a tensible clamp ( 34 ) against the concrete sleeper ( 16 ). A resilient intermediate plate ( 52 ) is disposed between the rail flange ( 14 ) and the standard concrete sleeper ( 16 ) and, at their ends remote from the rail ( 12 ), the angle guide plates ( 30 ) include a first ( 24 ) and a second surface ( 28 ), the first surface ( 24 ) being inclined obliquely to the vertical in the mounted position and abutting a correspondingly shaped sloping surface ( 44 ) of the standard concrete sleeper ( 16 ). The second surface ( 28 ) is aligned substantially vertically and rises over the top of the standard concrete sleeper ( 16 ). | 4 |
RELATED APPLICATION DATA
[0001] This application is a divisional patent application of U.S. Ser. No. 10/705,819 filed on Nov. 13, 2003, which is a divisional patent application of U.S. Ser. No. 09/890,650 filed Mar. 22, 2002 and now issued as U.S. Pat. No. 6,685,947, which is a 371 of International Patent Application No. PCT/AU00/00070 filed on Feb. 7, 2000, which claims benefit of foreign priority under 35 USC §119 from Australian Patent Application No. PP8533 filed on Feb. 5, 1999 and Australian Patent Application No. PQ2013 filed on Aug. 4, 1999. The contents of U.S. Ser. No. 10/705,819 filed on Nov. 13, 2003 and U.S. Ser. No. 09/890,650 (U.S. Pat. No. 6,685,947) filed Mar. 22, 2002 are each incorporated in their entirety by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to T helper cell epitopes derived from Canine Distemper Virus (CDV). The present invention relates to compositions including at least one T helper cell epitope and optionally B cell epitopes and/or CTL epitopes.
BACKGROUND OF THE INVENTION
[0003] For any peptide to be able to induce an effective antibody response it must contain particular sequences of amino acids known as epitopes that are recognised by the immune system. In particular, for antibody responses, epitopes need to be recognised by specific immunoglobulin (Ig) receptors present on the surface of B lymphocytes. It is these cells which ultimately differentiate into plasma cells capable of producing antibody specific for that epitope. In addition to these B cell epitopes, the immunogen must also contain epitopes that are presented by antigen presenting cells (APC) to specific receptors present on helper T lymphocytes, the cells which are necessary to provide the signals required for the B cells to differentiate into antibody producing cells.
[0004] In the case of viral infections and in many cases of cancer, antibody is of limited benefit in recovery and the immune system responds with cytotoxic T cells (CTL) which are able to kill the virus-infected or cancer cell. Like helper T cells, CTL are first activated by interaction with APC bearing their specific peptide epitope presented on the surface, this time in association with MHC class I rather than class II molecules. Once activated the CTL can engage a target cell bearing the same peptide/class I complex and cause its lysis. It is also becoming apparent that helper T cells play a role in this process; before the APC is capable of activating the CTL it must first receive signals from the helper T cell to upregulate the expression of the necessary costimulatory molecules.
[0005] Helper T cell epitopes are bound by molecules present on the surface of APCs that are coded by class II genes of the major histocompatibility complex (MHC). The complex of the class II molecule and peptide epitope is then recognised by specific T-cell receptors (TCR) on the surface of T helper lymphocytes. In this way the T cell, presented with an antigenic epitope in the context of an MHC molecule, can be activated and provide the necessary signals for the B lymphocyte to differentiate. Traditionally the source of helper T cell epitopes for a peptide immunogen is a carrier protein to which peptides are covalently coupled but this coupling procedure can introduce other problems such as modification of the antigenic determinant during the coupling process and the induction of antibodies against the carrier at the expense of antibodies which are directed toward the peptide (Schutze, M. P., Leclerc, C. Jolivet, M. Audibert, F. Chedid, L. Carrier-induced epitopic suppression, a major issue for future synthetic vaccines. J. Immunol. 1985, 135, 2319-2322; DiJohn, D., Torrese, J. R. Murillo, J. Herrington, D. A. et al. Effect of priming with carrier on response to conjugate vaccine. The Lancet. 1989, 2, 1415-1416). Furthermore, the use of irrelevant proteins in the preparation introduces issues of quality control. The choice of appropriate carrier proteins is very important in designing peptide vaccines and their selection is limited by factors such as toxicity and feasibility of their large scale production. There are other limitations to this approach including the size of the peptide load that can be coupled and the dose of carrier that can be safely administered (Audibert, F. a. C., L. 1984. Modern approaches to vaccines. Molecular and chemical basis of virus virulence and immunogenicity., Cold Spring Harbor Laboratory, New York.). Although carrier molecules allow the induction of a strong immune response they are also associated with undesirable effects such as suppression of the anti-peptide antibody response (Herzenberg, L. A. and Tokuhisa, T. 1980. Carrier-priming leads to hapten-specific suppression. Nature 285:664; Schutze, M. P., Leclerc, C., Jolivet, M., Audibert, F., and Chedid, L. 1985. Carrier-induced epitopic suppression, a major issue for future synthetic vaccines. J Immunol 135:2319; Etlinger, H. M., Felix, A. M., Gillessen, D., Heimer, E. P., Just, M., Pink, J. R., Sinigaglia, F., Sturchler, D., Takacs, B., Trzeciak, A., and et, a. 1988. Assessment in humans of a synthetic peptide-based vaccine against the sporozoite stage of the human malaria parasite, Plasmodium falciparum . J Immunol 140:626).
[0006] In general then, an immunogen must contain epitopes capable of being recognised by helper T cells in addition to the epitopes that will be recognised by surface Ig or by the receptors present on cytotoxic T cells. It should be realised that these types of epitopes may be very different. For B cell epitopes, conformation is important as the B cell receptor binds directly to the native immunogen. In contrast, epitopes recognised by T cells are not dependent on conformational integrity of the epitope and consist of short sequences of approximately nine amino acids for CTL and slightly longer sequences, with less restriction on length, for helper T cells. The only requirements for these epitopes are that they can be accommodated in the binding cleft of the class I or class II molecule respectively and that the complex is then able to engage the T-cell receptor. The class II molecule's binding site is open at both ends allowing a much greater variation in the length of the peptides bound (Brown, J. H., T. S. Jardetzky, J. C. Gorga, L. J. Stern, R. G. Urban, J. L. Strominger and D. C. Wiley. 1993. Three-dimensional structure of the human class II histocompatibility antigen HLA-DR1. Nature 364:33) with epitopes as short as 8 amino acid residues being reported (Fahrer, A. M., Geysen, H. M., White, D. O., Jackson, D. C. and Brown, L. E. Analysis of the requirements for class II-restricted T-cell recognition of a single determinant reveals considerable diversity in the T-cell response and degeneracy of peptide binding to I-Ed J. Immunol. 1995. 155: 2849-2857).
[0007] Canine distemper virus (CDV) belongs to the subgroup of morbillivirus of paramyxovirus family of negative-stranded RNA viruses. Other viruses which are members of this group are measles virus and rinderpest virus. Development of peptide based vaccines has aroused considerable interest in identification of B and T cell epitopes from sequences of proteins. The rationale for using T cell epitopes from proteins such as the F protein of CDV is that young dogs are inoculated against CDV in early life and will therefore possess helper T cells specific for helper T cell epitopes present on this protein. Subsequent exposure to a vaccine which contains one or more of the epitopes will therefore result in recruitment of existing helper T cells and consequently an enhanced immune response. Such helper T cell epitopes could, however, be administered to unprimed animals and still induce an immune response. The present inventors aimed to identify canine T cell epitopes from the sequence of CDV fusion protein so that these epitopes can then be used in the design of peptide based vaccines, in particular, for the canine and related species.
[0008] LHRH (Luteinising hormone releasing hormone) is a ten amino acids long peptide hormone whose sequence is conserved in mammals. It is secreted by the hypothalamus and controls the reproductive physiology of both males and females. The principle of development of LHRH-based immunocontraceptive vaccines is based on observations that antibodies to LHRH block the action of the hormone on pituitary secretion of luteinising hormone and follicle stimulating hormone, leading to gonadal atrophy and sterility in mammals.
[0009] Most LHRH vaccines that have been developed consist of LHRH chemically conjugated to protein carriers to provide T cell help for the generation of anti-LHRH antibodies. It has been shown that upon repeated inoculation of LHRH-protein carrier conjugates the anti-LHRH titre decreases due to the phenomenon known as “carrier induced epitope suppression”. One aim of the present inventors is to replace protein carriers in the vaccines with defined T helper epitopes (TH-epitopes) so as to eliminate “carrier induced epitope suppression”.
SUMMARY OF THE INVENTION
[0010] The present inventors have identified a number of 17 residue peptides each of which includes a T helper cell epitope. As will be readily appreciated the majority of these peptides are not minimal T helper cell epitopes. Typically class II molecules have been shown to be associated with peptides as short as 8 amino acids (Fahrer et al., 1995 ibid) but usually of 12-19 amino acids (Chicz, R. M., Urban, R. G., Gorga, J. C., Vignali, D. A. A., Lane, W. S. and Strominger, J. L. Specificity and promiscuity among naturally processed peptides bound to HLA-DR alleles. J Exp Med 1993, 178, 27-47; Chicz, R. M., Urban, R. G., Lane, W. S., Gorga, J. C., Stern, L. J., Vignali, D. A. A. and Strominger, J. L. Predominant naturally processed peptides bound to HLA-DR1 are derived from MHC-related molecules and are heterogeneous in size. Nature 1992, 358, 764-8), although, peptides up to 25 amino acids in length have been reported to bind to class II (reviewed in Rammensee, H.-G. Chemistry of peptide associated with class I and class II molecules. Curr Opin Immunol 1995, 7, 85-95.).
[0011] Thus peptide epitopes that range in length between 8 and 25 amino acid residues can bind to class II molecules. The shorter peptides are “core” epitopes that may have less activity than longer sequences but it is a trivial exercise to truncate longer sequences at the N- or the C-terminus to yield shorter sequences that have the same or better activity than the parent sequence.
[0012] Accordingly in a first aspect the present invention consists in a T helper cell epitope, the epitope being contained within a peptide sequence selected from the group consisting of SSKTQTHTQQDRPPQPS (SEQ ID NO: 1); QPSTELEETRTSRARHS (SEQ ID NO: 2); RHSTTSAQRSTHYDPRT (SEQ ID NO: 3); PRTSDRPVSYTMNRTRS (SEQ ID NO: 4); TRSRKQTSHRLKNIPVH (SEQ ID NO: 5); SHQYLVIKLIPNASLIE (SEQ ID NO: 6); IGTDNVHYKIMTRPSHQ (SEQ ID NO: 7); YKIMTRPSHQYLVIKLI (SEQ ID NO: 8); KLIPNASLIENCTKAEL (SEQ ID NO: 9); AELGEYEKLLNSVLEPI (SEQ ID NO: 10); KLLNSVLEPINQALTLM (SEQ ID NO: 11); EPINQALTLMTKNVKPL (SEQ ID NO: 12); FAGVVLAGVALGVATAA (SEQ ID NO: 13); GVALGVATAAQITAGIA (SEQ ID NO: 14); TAAQITAGIALHQSNLN (SEQ ID NO: 15); GIALHQSNLNAQAIQSL (SEQ ID NO: 16); NLNAQAIQSLRTSLEQS (SEQ ID NO: 17); QSLRTSLEQSNKAIEEI (SEQ ID NO: 18); EQSNKAIEEIREATQET (SEQ ID NO: 19); TELLSIFGPSLRDPISA (SEQ ID NO: 20); PRYIATNGYLISNFDES (SEQ ID NO: 21); CIRGDTSSCARTLVSGT (SEQ ID NO: 22); DESSCVFVSESAICSQN (SEQ ID NO: 23); TSTIINQSPDKLLTFIA (SEQ ID NO: 24), SPDKLLTFIASDTCPLV (SEQ ID NO: 25) and SGRRQRRFAGVVLAGVA (SEQ ID NO: 26).
[0013] In a second aspect the present invention consists in a composition for use in raising an immune response in an animal, the composition comprising at least one T helper cell epitope, the at least one T helper cell epitope being contained within a peptide sequence selected from the group consisting of SSKTQTHTQQDRPPQPS (SEQ ID NO: 1); QPSTELEETRTSRARHS (SEQ ID NO: 2); RHSTTSAQRSTHYDPRT (SEQ ID NO: 3); PRTSDRPVSYTMNRTRS (SEQ ID NO: 4); TRSRKQTSHRLKNIPVH (SEQ ID NO: 5); SHQYLVIKLIPNASLIE (SEQ ID NO: 6); IGTDNVHYKIMTRPSHQ (SEQ ID NO: 7); YKIMTRPSHQYLVIKLI (SEQ ID NO: 8); KLIPNASLIENCTKAEL (SEQ ID NO: 9); AELGEYEKLLNSVLEPI (SEQ ID NO: 10); KLLNSVLEPINQALTLM (SEQ ID NO: 11); EPINQALTLMTKNVKPL (SEQ ID NO: 12); FAGVVLAGVALGVATAA (SEQ ID NO: 13); GVALGVATAAQITAGIA (SEQ ID NO: 14); TAAQITAGIALHQSNLN (SEQ ID NO: 15); GIALHQSNLNAQAIQSL (SEQ ID NO: 16); NLNAQAIQSLRTSLEQS (SEQ ID NO: 17); QSLRTSLEQSNKAIEEI (SEQ ID NO: 18); EQSNKAIEEIREATQET (SEQ ID NO: 19); TELLSIFGPSLRDPISA (SEQ ID NO: 20); PRYIATNGYLISNFDES (SEQ ID NO: 21); CIRGDTSSCARTLVSGT (SEQ ID NO: 22); DESSCVFVSESAICSQN (SEQ ID NO: 23); TSTIINQSPDKLLTFIA (SEQ ID NO: 24), SPDKLLTFIASDTCPLV (SEQ ID NO: 25) and SGRRQRRFAGVVLAGVA (SEQ ID NO: 26).
[0014] In a preferred embodiment of the present invention the composition comprises at least one peptide selected from the group consisting of SSKTQTHTQQDRPPQPS (SEQ ID NO: 1); QPSTELEETRTSRARHS (SEQ ID NO: 2); RHSTTSAQRSTHYDPRT (SEQ ID NO: 3); PRTSDRPVSYTMNRTRS (SEQ ID NO: 4); TRSRKQTSHRLKNIPVH (SEQ ID NO: 5); SHQYLVIKLIPNASLIE (SEQ ID NO: 6); IGTDNVHYKIMTRPSHQ (SEQ ID NO: 7); YKIMTRPSHQYLVIKLI (SEQ ID NO: 8); KLIPNASLIENCTKAEL (SEQ ID NO: 9); AELGEYEKLLNSVLEPI (SEQ ID NO: 10); KLLNSVLEPINQALTLM (SEQ ID NO: 11); EPINQALTLMTKNVKPL (SEQ ID NO: 12); FAGVVLAGVALGVATAA (SEQ ID NO: 13); GVALGVATAAQITAGIA (SEQ ID NO: 14); TAAQITAGIALHQSNLN (SEQ ID NO: 15); GIALHQSNLNAQAIQSL (SEQ ID NO: 16); NLNAQAIQSLRTSLEQS (SEQ ID NO: 17); QSLRTSLEQSNKAIEEI (SEQ ID NO: 18); EQSNKAIEEIREATQET (SEQ ID NO: 19); TELLSIFGPSLRDPISA (SEQ ID NO: 20); PRYIATNGYLISNFDES (SEQ ID NO: 21); CIRGDTSSCARTLVSGT (SEQ ID NO: 22); DESSCVFVSESAICSQN (SEQ ID NO: 23); TSTIINQSPDKLLTFIA (SEQ ID NO: 24), SPDKLLTFIASDTCPLV (SEQ ID NO: 25) and SGRRQRRFAGVVLAGVA (SEQ ID NO: 26).
[0015] It is further preferred that the composition further comprises at least one B cell epitope and/or at least one CTL epitope.
[0016] In yet another preferred embodiment the at least one B cell epitope and/or the at least one CTL epitope are linked to at least one of the T helper cell epitopes. It is also preferred that the composition comprises a plurality of epitope constructs in which each comprises at least one T helper cell epitope and at least one B cell epitope. Alternatively the composition may comprises a plurality of epitope constructs in which each comprises at least one T helper cell epitope and at least one CTL epitope.
[0017] It will be understood that the B cell epitope or CTL epitope may be any epitope. A currently preferred B cell epitope is an LHRH B cell epitope.
[0018] The composition of the present invention may comprises a plurality of T helper cell epitopes. These epitopes may be singular or be linked together to form a single polypeptide. It will be understood that where the epitopes are linked to together in a single polypeptide the epitopes may be contiguous or spaced apart by additional amino acids which are not themselves part of the T helper cell epitopes.
[0019] As discussed above in one embodiment the T helper cell epitopes and at least one B cell epitope and/or at least one CTL epitope in which the epitopes are linked. This may be done by simple covalent linkage of the peptides. In another embodiment the epitopes are polymerised, most preferably such as described in PCT/AU98/00076, the disclosure of which is incorporated herein by reference.
[0020] In yet another preferred embodiment the composition further comprises a pharmaceutically acceptable excipient, preferably an adjuvant.
[0021] In a further aspect the present invention consists in a method of inducing an immune response in an animal, the method comprising administering to the animal the composition of the second aspect of the present invention.
[0022] Pharmaceutically acceptable carriers or diluents include those used in compositions suitable for oral, rectal, nasal, topical (including buccal and sublingual), vaginal, parenteral (including subcutaneous, intramuscular, intravenous, intradermal, intrathecal and epidural) administration. They are non-toxic to recipients at the dosages and concentrations employed. Representative examples of pharmaceutically acceptable carriers or diluents include, but are not limited to water, isotonic solutions which are preferably buffered at a physiological pH (such as phosphate-buffered saline or Tris-buffered saline) and can also contain one or more of, mannitol, lactose, trehalose, dextrose, glycerol, ethanol or polypeptides (such as human serum albumin). The compositions may conveniently be presented in unit dosage form and may be prepared by any of the methods well known in the art of pharmacy.
[0023] As mentioned it is preferred that the composition includes an adjuvant. As will be understood an “adjuvant” means a composition comprised of one or more substances that enhances the immunogenicity and efficacy of a vaccine composition. Non-limiting examples of suitable adjuvants include squalane and squalene (or other oils of animal origin); block copolymers; detergents such as Tween®-80; Quil® A, mineral oils such as Drakeol or Marcol, vegetable oils such as peanut oil; Corynebacterium -derived adjuvants such as Corynebacterium parvum; Propionibacterium -derived adjuvants such as Propionibacterium acne; Mycobacterium bovis (Bacille Calmette and Guerin or BCG); interleukins such as interleukin 2 and interleukin 12; monokines such as interleukin 1; tumour necrosis factor; interferons such as gamma interferon; combinations such as saponin-aluminium hydroxide or Quil-A aluminium hydroxide; liposomes; ISCOM adjuvant; mycobacterial cell wall extract; synthetic glycopeptides such as muramyl dipeptides or other derivatives; Avridine; Lipid A derivatives; dextran sulfate; DEAE-Dextran or with aluminium phosphate; carboxypolymethylene such as Carbopol' EMA; acrylic copolymer emulsions such as Neocryl A640 (e.g. U.S. Pat. No. 5,047,238); vaccinia or animal poxvirus proteins; sub-viral particle adjuvants such as cholera toxin, or mixtures thereof.
[0024] As will be recognised by those skilled in the art modifications may be made to the peptides of the present invention without complete abrogation of biological activity. These modifications include additions, deletions and substitutions, in particular conservative substitutions. It is intended that peptides including such modifications which do not result in complete loss of activity as T helper cell epitopes are within the scope of the present invention.
[0025] Whilst the concept of substitution is well known in the field the types of substitutions envisaged are set out below.
Preferred Original Residue Exemplary Substitutions Substitutions Ala (A) val; leu; ile Val Arg (R) lys; gln; asn Lys Asn (N) gln; his; lys; arg Gln Asp (D) glu Glu Cys (C) ser Ser Gln (Q) asn asn Glu (E) asp asp Gly (G) pro pro His (H) asn; gln; lys; arg arg Ile (I) leu; val; met; ala; phe, norleucine leu Leu (L) norleucine, ile; val; met; ala; phe ile Lys (K) arg; gln; asn arg Met (M) leu; phe; ile; leu Phe (F) leu; val; ile; ala leu Pro (P) Gly gly Ser (S) Thr thr Thr (T Ser ser Trp (W) Tyr tyr Tyr (Y) trp; phe; thr; ser phe Val (V) ile; leu; met; phe ala; norleucine leu
[0026] Another type of modification of the peptides envisaged include, but are not limited to, modifications to side chains, incorporation of unnatural amino acids and/or their derivatives during peptide synthesis and the use of crosslinkers and other methods which impose conformational constraints on the peptides.
[0027] Examples of side chain modifications contemplated by the present invention include, but are not limited to, modifications of amino groups such as by reductive alkylation by reaction with an aldehyde followed by reduction with NaBH 4 ; amidation with methylacetimidate; acylation with acetic anhydride; carbamoylation of amino groups with cyanate; trinitrobenzylation of amino groups with 2,4,6-trinitrobenzene sulphonic acid (TNBS); acylation of amino groups with succinic anhydride and tetrahydrophthalic anhydride; and pyridoxylation of lysine with pyridoxal-5-phosphate followed by reduction with NaBH 4 .
[0028] The guanidine group of arginine residues may be modified by the formation of heterocyclic condensation products with reagents such as 2,3-butanedione, phenylglyoxal and glyoxal.
[0029] The carboxyl group may be modified by carbodiimide activation via O-acylisourea formation followed by subsequent derivitisation, for example, to a corresponding amide.
[0030] Tryptophan residues may be modified by, for example, oxidation with N-bromosuccinimide or alkylation of the indole ring with 2-hydroxy-5-nitrobenzyl bromide or sulphenyl halides. Tyrosine residues on the other hand, may be altered by nitration with tetranitromethane to form 3-nitrotyrosine derivative.
[0031] Modification of the imidazole ring of a histidine residue may be accomplished by alkylation with iodoacetic acid derivatives or N-carbethoxylation with diethylpyrocarbonate.
[0032] Examples of incorporating unnatural amino acids and derivatives during peptide synthesis include, but are not limited to, use of norleucine, 4-amino butyric acid, 4-amino-3-hydroxy-5-phenylpentanoic acid, 6-aminohexanoic acid, t-butylglycine, norvaline, phenylglycine, ornithine, sarcosine, 4-amino-3-hydroxy-6-methylheptanoic acid; 2-thienyl alanine and/or D-isomers of amino acids.
[0033] The peptides of the present invention may be derived from CDV. Alternatively, the peptide or combination of peptide epitopes may be produced by recombinant DNA technology. It is, however, preferred that the peptides are produced synthetically using methods well known in the field. For example, the peptides may be synthesised using solution synthesis or solid phase synthesis as described, for example, in Chapter 9 entitled “Peptide Synthesis” by Atherton and Sheppard which is included in a publication entitled “Synthetic Vaccines” edited by Nicholson and published by Blackwell Scientific Publications. Preferably a solid phase support is utilised which may be polystyrene gel beads wherein the polystyrene may be cross-linked with a small proportion of divinylbenzene (e.g. 1%) which is further swollen by lipophilic solvents such as dichloromethane or more polar solvents such as dimethylformamide (DMF). The polystyrene may be functionalised with chloromethyl or aminomethyl groups. Alternatively, cross-linked and functionalised polydimethyl-acrylamide gel is used which may be highly solvated and swollen by DMF and other dipolar aprotic solvents. Other supports can be utilised based on polyethylene glycol which is usually grafted or otherwise attached to the surface of inert polystyrene beads. In a preferred form, use may be made of commercial solid supports or resins which are selected from PAL-PEG-PS, PAC-PEG-PS, KA, KR or TGR.
[0034] In solid state synthesis, use is made of reversible blocking groups which have the dual function of masking unwanted reactivity in the α-amino, carboxy or side chain functional groups and of destroying the dipolar character of amino acids and peptides which render them inactive. Such functional groups can be selected from t-butyl esters of the structure RCO—OCMe 3 —CO. Use may also be made of the corresponding benzyl esters having the structure RCO—OCH 2 —C 6 H 5 and urethanes having the structure C 6 H 5 CH 2 OCO—NHR which are known as the benzyloxycarbonyl or Z-derivatives and any Me 3 -COCO—NHR, which are known as t-butoxylcarbonyl, or Boc derivatives. Use may also be made of derivatives of fluorenyl methanol and especially the fluorenyl-methoxy carbonyl or Fmoc group. Each of these types of protecting group is capable of independent cleavage in the presence of one other so that frequent use is made, for example, of BOC-benzyl and Fmoc-tertiary butyl protection strategies.
[0035] Reference also should be made to a condensing agent to link the amino and carboxy groups of protected amino acids or peptides. This may be done by activating the carboxy group so that it reacts spontaneously with a free primary or secondary amine. Activated esters such as those derived from p-nitrophenol and pentafluorophenol may be used for this purpose. Their reactivity may be increased by addition of catalysts such as 1-hydroxybenzotriazole. Esters of triazine DHBT (as discussed on page 215-216 of the abovementioned Nicholson reference) also may be used. Other acylating species are formed in situ by treatment of the carboxylic acid (i.e. the N-alpha-protected amino acid or peptide) with a condensing reagent and are reacted immediately with the amino component (the carboxy or C-protected amino acid or peptide). Dicyclohexylcarbodiimide, the BOP reagent (referred to on page 216 of the Nicholson reference), O'Benzotriazole-N,N,N′N-tetra methyl-uronium hexafluorophosphate (HBTU) and its analogous tetrafluoroborate are frequently used condensing agents.
[0036] The attachment of the first amino acid to the solid phase support may be carried out using BOC-amino acids in any suitable manner. In one method BOC amino acids are attached to chloromethyl resin by warming the triethyl ammonium salts with the resin. Fmoc-amino acids may be coupled to the p-alkoxybenzyl alcohol resin in similar manner. Alternatively, use may be made of various linkage agents or “handles” to join the first amino acid to the resin. In this regard, p-hydroxymethyl phenylacetic acid linked to aminomethyl polystyrene may be used for this purpose.
[0037] Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
DETAILED DESCRIPTION OF THE INVENTION
[0038] In order that the nature of the present invention may be more readily understood preferred forms there of will now be described with reference to the following non-limiting examples.
FIGURE LEGENDS
[0039] FIG. 1 . Amino acid sequence of the fusion protein of CDV (SEQ ID NO: 27)
[0040] FIG. 2 a . Stimulation indices to Th-epitope P25 and its truncated versions in Dog #70 immunised with P25-LHRH (X-axis concentration of peptides nmoles/well).
[0041] FIG. 2 b Stimulation indices to Th-epitope P25 and its truncated versions in Dog #73 immunised with P25-LHRH (X-axis concentration of peptides nmoles/well).
[0042] FIG. 2 c Stimulation indices to Th-epitope P25 and its truncated versions in Dog #127 immunised with P25-LHRH (X-axis concentration of peptides nmoles/well).
[0043] FIG. 2 d Stimulation indices to Th-epitope P25 and its truncated versions in Dog #993 immunised with P25-LHRH (X-axis concentration of peptides nmoles/well).
[0044] FIG. 3 a . Stimulation indices to Th-epitope P27 and its truncated 15-mer in Dog #105 immunised with P27-LHRH. (X-axis concentration of peptides nmoles/well).
[0045] FIG. 3 b . Stimulation indices to Th-epitope P27 and its truncated 15-mer in) Dog #94 immunised with P27-LHRH. (X-axis concentration of peptides nmoles/well).
[0046] FIG. 3 c . Stimulation indices to Th-epitope P27 and its truncated 15-mer in Dog #20 immunised with P27-LHRH. (X-axis concentration of peptides nmoles/well).
[0047] FIG. 3 d . Stimulation indices to Th-epitope P27 and its truncated 15-mer in Dog #101 immunised with P27-LHRH. (X-axis concentration of peptides nmoles/well).
[0048] FIG. 4 a . Stimulation indices to Th-epitope P35 and its truncated versions in Dog #19 immunised with P35-LHRH (X-axis concentration of peptides nmoles/well).
[0049] FIG. 4 b . Stimulation indices to Th-epitope P35 and its truncated versions in Dog #100 immunised with P35-LHRH (X-axis concentration of peptides nmoles/well).
[0050] FIG. 4 c . Stimulation indices to Th-epitope P35 and its truncated versions in Dog #96 immunised with P35-LHRH (X-axis concentration of peptides nmoles/well).
[0051] FIG. 4 d . Stimulation indices to Th-epitope P35 and its truncated versions in Dog #102 immunised with P35-LHRH (X-axis concentration of peptides nmoles/well).
EXAMPLE 1
[0000] Identification of T Helper Cell Epitopes
[0000] Methods and Results:
[0052] Towards identification of canine T cell epitopes 94, 17 residue overlapping peptides were designed encompassing the entire sequence of fusion protein of canine distemper virus (CDV). The 17mer peptides were numbered sequentially for identification starting from the N-terminus. The sequence of the fusion protein of CDV as determined by Barrett et al 1987 (Virus Res. 8, 373-386) is shown in FIG. 1 . The peptides were used in T-cell proliferation assays using peripheral blood lymphocytes (PBMC) from dogs immunised with Canvac™ 3 in 1 vaccine (CSL Limited) which contains live CDV.
[0053] Initially, four dogs were used and they were boosted with the Canvac™ 3 in 1 vaccine twice with four to six weeks between each vaccination. The dogs were bled after each booster vaccination and the PBMCs were tested against the peptides. No significant proliferation to peptides was observed.
[0054] Since CDV has been reported to be lymphotropic and the vaccine consists of live CDV, there was the possibility that it may be sequestered in lymphoid organs preventing significant numbers of precursor T cells entering the peripheral system. To increase the frequency of peripheral blood anti-CDV T cells dogs were boosted with heat killed CDV (obtained as a pellet from virus culture medium, CSL Limited). Two weeks later, the dogs were bled and the PBMCs tested for proliferation against the peptides. Again there was no proliferation to the peptide antigens.
[0055] An alternate strategy was used to increase the precursor frequency of specific T cells recognising the CDV peptides. Fresh PBMCs obtained from these hyperimmunised dogs were subjected to stimulation in vitro with pools of all 94 peptides for 30 minutes at 37° C. The cells were then washed to remove any excess peptides and cultured for 7 days. This population of T cells was then tested with autologous APCs with every single peptide as the antigen. Table 1 shows the peptides to which significant (stimulation index >2) levels of proliferation were observed.
[0056] To confirm this observation, the same four dogs were bled again, five weeks after receiving the dose of killed virus. The PBMCs were stimulated in vitro with pools of either all 94 peptides or peptides 21-40 (because most of the activity was in this region) and after 7 days of culture the stimulated T cells were tested against individual peptides. Significant stimulatory indices were obtained with all peptides, confirming the above results. Four more dogs which received only one dose of 3 in 1 vaccine were tested using the in vitro stimulation method and all four dogs responded to the majority of peptides shown in Table 2.
[0057] The above peptides were also tested on cells from additional dogs, with results shown in Table 3. Peptides P64, P74 and P75 were also shown to react strongly with peripheral blood mononuclear cells from dogs of various breeds immunised with CDV (Table 4), and are therefore identified as strong T-helper epitopes.
TABLE 1 Identification of canine T cell epitopes from the sequence of fusion protein of CDV. Beagle Beagle Beagle Beagle Foxhound Foxhound Foxhound Foxhound Peptides (Dog #18) (Dog #19) (Dog #20) (Dog #21) p2 2* <2 8 3.9 p4 4.9 <2 3.3 4.6 p6 2.5 <2 4 5.1 p10 2.3 <2 3.2 9.1 p24 5.8 9.9 2.8 29 p25 3.2 11.9 4.5 17 p27 3.3 34 6.7 14.8 p29 3.5 42 4.4 <2 p35 3.1 57 3.3 22 p36 6.7 3.7 3.3 16 p37 6.9 10.9 8.2 26 p38 2.8 6.7 3.6 4.2 p47 3.3 85.7 2.9 1.9 p62 <2 51 5.6 4.2 p68 6.6 <2 <2 11.7 *Stimulatory index
[0058]
TABLE 2
Identification of canine T cell epitopes from the
sequence of fusion protein of CDV.
Beagle
Beagle
Beagle
Foxhound
Foxhound
Foxhound
Beagle Foxhound
Peptides
(Dog #70)
(Dog #71)
(Dog #72)
(Dog #73)
p8
2.2
p22
2.6
p24
3.2
2.2
p25
1.5
2.9
2
12
p27
2.7
3.5
4.8
p28
2
p29
2
6
p33
1.6
p35
1.7
6.8
p37
1.7
p62
3
[0059]
TABLE 3
Identification of canine T cell epitopes from the
sequence of fusion protein of CDV.
Peptides
Kelpie Foxhound (Dog #125)
Kelpie Foxhound (Dog #126)
p23
3.2
p27
4.5
8.5
p28
1.9
p29
3.6
p33
6
p34
2.1
p35
3.8
10
p36
3
p37
2.5
p38
2.2
p39
2.9
p47
2.7
p62
2.4
p68
2.9
[0060]
TABLE 4
Identification of canine T cell epitopes from
the sequence of fusion protein of CDV.
Beagle
Beagle
Beagle
Beagle
Pep-
Poodle
Fox-
Fox-
Fox-
Fox-
tides
Shitzu
hound#18
hound#19
hound#20
hound#21
P64
50.0
2.5
2.5
P74
4.0
1.7
6.0
P75
10
2.5
7.2
[0061] Once again the same peptides and one additional peptide P32 were tested on cells from additional dogs. These peptides were also shown to react strongly with peripheral blood mononuclear cells from dogs of various breeds immunised with CDV (Table 5), and are therefore identified as strong T-helper epitopes.
[0062] In conclusion, 26 peptides were identified as canine T helper cell epitopes in the fusion protein of CDV. The sequences of each of these peptides are set out in Table 6.
[0063] These T helper cell epitopes will have usefulness as components of animal, in particular, canine vaccines, either simply as synthetic peptide based vaccines and as additions to vaccines containing more complex antigens.
TABLE 5 Identification of canine T cell epitopes from the sequence of fusion protein of CDV. Poodle Grey Fox Terrier Kelpie Border Peptides Shitzu hound Terrier Cross Pointer Collie P2 140 <2 <2 <2 2.6 2 P4 44 2 <2 2 3.5 2 P6 38 <2 <2 <2 <2 2 P8 100 2 <2 <2 2.8 2 P10 50 2 2.2 2.1 2.4 3 P25 <2 <2 2.6 <2 2.6 <2 P29 2 <2 <2 2 <2 <2 P32 <2 2 <2 <2 <2 <2 P33 <2 <2 <2 <2 2 2 P35 <2 <2 2.2 <2 2 2 P37 <2 <2 <2 2 2 <2 P62 24 <2 <2 <2 <2 <2 P64 50 <2 <2 <2 <2 <2 P68 5 <2 <2 <2 <2 <2 P74 4 <2 <2 <2 <2 <2 P75 10 <2 <2 <2 <2 <2
[0064]
TABLE 6
Sequences of the peptides:
P2
SSKTQTHTQQDRPPQPS (SEQ ID NO: 1)
P4
QPSTELEETRTSRARHS (SEQ ID NO: 2)
P6
RHSTTSAQRSTHYDPRT (SEQ ID NO: 3)
P8
PRTSDRPVSYTMNRTRS (SEQ ID NO: 4)
P10
TRSRKQTSHRLKNIPVH (SEQ ID NO: 5)
P24
SHQYLVIKLIPNASLIE (SEQ ID NO: 6)
P22
IGTDNVHYKIMTRPSHQ (SEQ ID NO: 7)
P23
YKIMTRPSHQYLVIKLI (SEQ ID NO: 8)
P25
KLIPNASLIENCTKAEL (SEQ ID NO: 9)
P27
AELGEYEKLLNSVLEPI (SEQ ID NO: 10
P28
KLLNSVLEPINQALTLM (SEQ ID NO: 11)
P29
EPINQALTLMTKNVKPL (SEQ ID NO: 12)
P32
SGRRQRRFAGVVLAGVA (SEQ ID NO: 26)
P33
FAGVVLAGVALGVATAA (SEQ ID NO: 13)
P34
GVALGVATAAQITAGIA (SEQ ID NO: 14)
P35
TAAQITAGIALHQSNLN (SEQ ID NO: 15)
P36
GIALHQSNLNAQAIQSL (SEQ ID NO: 16)
P37
NLNAQAIQSLRTSLEQS (SEQ ID NO: 17)
P38
QSLRTSLEQSNKAIEEI (SEQ ID NO: 18)
P39
EQSNKAIEEIREATQET (SEQ ID NO: 19)
P47
TELLSIFGPSLRDPISA (SEQ ID NO: 20)
P62
PRYIATNGYLISNFDES (SEQ ID NO: 21)
P68
CIRGDTSSCARTLVSGT (SEQ ID NO: 22)
P64
DESSCVFVSESAICSQN (SEQ ID NO: 23)
P74
TSTIINQSPDKLLTFIA (SEQ ID NO: 24)
P75
SPDKLLTFIASDTCPLV (SEQ ID NO: 25)
[0065] Selected sequences of the identified T-cell epitopes were tested for their ability to induce an antibody response to a linked B-cell epitope. Trials were conducted in dogs for assessment of antibody responses. The T-cell epitopes were linked to the B cell epitope LHRH (leuteinising hormone releasing hormone), with the T-cell epitope at the N-terminus and LHRH positioned at the carboxy terminus.
[0066] Peptides were synthesised using standard chemistry with Fmoc protection. All peptides were purified to at least 80% purity and the product checked by mass spectroscopy.
[0067] The peptides were produced as contiguous T-cell-B cell determinants. The LHRH sequence of Pyro Glu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly (SEQ ID NO: 28), or variations of it, was linked to the carboxyl terminus of each respective CDV T-helper epitope.
[0068] In-vivo evaluation of some of the T-helper epitopes was conducted in two trials, by vaccination of dogs with T-helper-LHRH sequences.
EXAMPLE 2
Trial K9-5
[0069] A total of 14 dogs of mixed sex were used in this trial. All had been previously vaccinated with a live CDV vaccine and had also been vaccinated against LHRH.
[0000] Vaccine Formulation.
[0070] Test peptides P25, P27, P35 from CDV were synthesised with LHRH at the C terminus of each T-helper epitope. The LHRH sequence used was the full 10 amino acids of the native LHRH. Each of the vaccine constructs, together with a control peptide comprising a mouse influenza T-cell epitope linked to a repeat malarial B-cell epitope (sequence shown in table below) were purified to 80-90% purity. All peptides were dissolved in 4M urea before dilution with sterile saline to an appropriate volume to give 40 nmoles per 1 mL dose. Iscomatrix™ was added to a final concentration of 150 ug/1 mL dose as adjuvant together with thiomersal preservative (0.01%).
[0071] ISCOM™ or Immunostimulating Complex (Barr, Sjolander and Cox, 1998, Advanced Drug Delivery Systems 32: 247-271) are a well characterised class of adjuvant comprised of a complex of phospholipid, cholesterol and saponin, usually with a protein incorporated into the complex. Where the complex is formed in the absence of protein antigen, then this complex is termed Iscomatrix™. The saponin used in the preparation of this adjuvant was Quil A.
[0000] Vaccination, Blood Samples and Assays.
[0072] All dogs were vaccinated with a 1 mL dose, delivered in the scruff of the neck. Vaccinations were given at 0 and 4 weeks and venous blood samples were obtained at intervals during the trial.
[0073] Effective T-cell help was determined by measuring the antibody response to LHRH by ELISA. Biological effectiveness of the peptide based vaccine was determined by measuring the levels of progesterone in female dogs and testosterone in male dogs.
TABLE 7 Trial Groups Peptide Dog Nos. Control-ALNNRFQIKGVELKS-(NANP)3 104, 998 (SEQ ID NO: 30) P25-LHRH 1-10 70, 73, 127, 993 P27-LHRH 1-10 20, 94, 101, 105 P35-LHRH 1-10 19, 96, 100, 102
Results
[0074] Pre-existing low antibody levels to LHRH were present in all dogs due to immunisation previously with a different vaccine. The control group of dogs exhibited a slow decrease in antibody levels.
[0075] Dogs immunised with P25-LHRH, P27-LHRH and P35-LHRH all showed strong antibody responses to the B-cell epitope (LHRH). This response persisted to 6 weeks post boost vaccination (see Table 8).
[0076] The biological potency of the vaccine was demonstrated by a significant reduction in progesterone or testosterone levels (see Tables 9 and 10).
TABLE 8 Anti LHRH Titres Anti LHRH Titres Dog 2 wks 6 wks Peptide No Prebleeds post boost post boost Control 104 1258 1975 1936 998 2559 1982 1947 Average 1794 1978 1941 Range 1258-2559 1975-1982 1936-1947 P25-LHRH (1-10) 70 856 24245 16697 73 42665 16922 127 1361 21485 19662 993 577 24879 15119 Average 886 23120 17242 Range 0-1361 21485-42665 15119-19662 p27-LHRH (1-10) 20 747 29653 8423 94 41247 22759 101 4256 52724 17353 105 944 12600 8366 Average 2004 25774 12049 Range 747-4256 12600-52724 8366-22759 p35-LHRH (1-10) 19 665 18033 6228 96 1621 26583 5744 100 580 17255 4829 102 180 11740 2963 Average 323 14233 3783 Range 180-1621 11740-26583 2963-6228
[0077]
TABLE 9
Progesterone results (nmol/L)
Dog
4 wks
6 wks
Peptide
No.
post primary
2 wks post boost
post boost
Control
998
5.17
4.28
<0
p25-LHRH (1-10)
127
3.04
4.83
<0
993
1.7
0.87
<0
p27-LHRH (1-10)
101
0.42
0.14
<0
p35-LHRH (1-10)
96
31.76
2.15
<0
100
<0
<0
<0
[0078]
TABLE 10
Testosterone results (nmol/L)
Dog
4 wks
6 wks
Peptide
No.
post primary
2 wks post boost
post boost
Control
104
9.69
2.51
3.31
p25-LHRH (1-10)
70
<0
<0
<0
73
5.38
<0
<0
p27-LHRH (1-10)
20
1.04
<0
<0
94
3.33
<0
<0
105
>47.7
<0
<0
p35-LHRH (1-10)
19
4.3
2.77
4.55
102
6.72
<0
<0
[0079] The effectiveness of selected T-cell epitopes from the F-protein of CDV in providing T-cell help of elicit antibody responses in dogs proves that the identified sequence are functional. These results also validate the scientific approach and usefulness of the in vitro screening method for identifying T-helper epitope sequences with in vivo activity.
EXAMPLE 3
Trial K9-8
[0080] A total of 35 dogs mixed sex were used in this trial. All had been previously vaccinated with a live CDV vaccine but had not been vaccinated against LHRH.
[0000] Vaccine Formulation:
[0081] The T-Helper epitopes were linked to a truncated form of LHRH, containing amino acids 2 to 10 of the native 10 amino acid sequence, as shown below:
(SEQ ID NO: 29) 2-10 LHRH His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly.
[0082] All vaccines were formulated as for Example 2, ie each 1 mL dose of vaccine contained 40 nmoles of peptide, 150 μg Iscomatrix™, and thiomersal as preservative.
[0083] Where dogs were vaccinated with a pool of peptides, the concentration of each peptide was adjusted to give equal concentrations and a total amount of 40 nmoles of LHRH epitope per 1 mL dose.
[0000] Vaccination, Blood Samples and Assays.
[0084] All dogs were vaccinated with a 1 mL dose, delivered in the scruff of the neck. Vaccinations were given at 0 and 4 weeks and venous blood samples were obtained at intervals during the trial.
[0085] Effective T-cell help was determined by measuring the antibody response to LHRH by ELISA. Biological effectiveness of the peptide based vaccine was determined by measuring the levels of progesterone in female dogs and testosterone in male dogs.
TABLE 11 Trial Groups Peptide Group Dog Nos. P25-LHRH 2-10 211, 195, 197,181 P27-LHRH 2-10 203, 191, 186, 201 P35-LHRH 2-10 217, 198, 187, 196 Pool: P25-LHRH 2-10, 212, 193, 178, 216, Y3 P27-LHRH 2-10, P35-LHRH 2-10 P2-LHRH 2-10 194, 199, 179, 220 P8-LHRH 2-10 Y4, Y6, 160, 200 P62-LHRH 2-10 219, 185, 221, 177 P75-LHRH 2-10 189, 222, 202, 176 Unvaccinated controls 190, 159
Results
[0086] Strong antibody responses to LHRH were demonstrated in dogs immunised with the T-cell-LHRH constructs with the T-cell epitopes P25, P27, P35, P62, P75, and the pool of T-cell-LHRH peptides comprising a combination of T-cell epitopes P25, P27 and P35 (see Table 12).
[0087] Low to undetectable antibody responses were seen in dogs immunised with P2 and P8-LHRH peptides (see Table 12). This was concluded to indicate that these T-cell peptides were not well recognised by Beagle-Foxhound dogs, which is consistent with their identification using PBMCs' from other dog breeds. The initial screening in Beagle foxhound dogs indicated that this breed of dog does not respond to these 2 T-cell epitopes.
[0088] As is well understood by those skilled in the art of peptide vaccines the response to individual peptides is genetically determined. The class II Major Histocompatability Complex (MHC II) is polymorphic. Class II molecules at the cell surface function to bind peptides for presentation to T-cells, which is required as part of the activation process for T-cells, including helper T-cells. The allelic forms of MHC class II bind discrete sets of peptide antigens, and thus the response to those antigens is genetically determined. Thus the results are interpreted to indicate that the Beagle—Foxhound breed of dog does not possess the appropriate MHC-II alleles to respond to P2 and P8, but that other breeds of dog do, eg. the Poodle Shitzu breed that were used to identify these peptides.
[0089] Control dogs showed no change in antibody levels to LHRH during the trial period and hormone levels were within normal ranges for the age and sex of the dogs (see Table 12).
TABLE 12 Anti-LHRH Titres Anti LHRH Titres Dog 4 wks after 2 wks post 4 wks post Peptide Group No primary boost boost Control 1 159 0 0 0 1 190 0 0 0 GMT Pool 2 Y3 1860 55659 95038 2 178 17900 416036 486793 2 193 8770 211369 189143 2 212 3766 121411 135293 2 216 8378 294769 642293 GMT 6207 177292 237798 P25-LHRH 3 181 1893 152264 131643 3 195 31197 205906 455193 3 197 14423 337698 240543 3 211 20607 142798 131643 GMT 11510 193037 214229 P27-LHRH 4 186 0 11206 17263 4 191 0 59154 125493 4 201 0 17041 34103 4 203 0 1000 857 GMT 0 18523 26698 P35-LHRH 5 187 2009 141775 55797 5 196 4868 237208 158040 5 198 1539 154375 68307 5 217 0 121050 40822 GMT 2469 103085 58002 P2-LHRH 6 179 0 0 0 6 194 0 0 0 6 199 0 0 0 6 220 0 0 0 GMT P8-LHRH 7 Y4 0 0 0 7 Y6 0 0 0 7 160 0 1200 ND 7 200 0 8000 2227 GMT P62-LHRH 8 177 1242 3821 2985 8 185 0 146581 67461 8 219 0 29353 28282 8 221 2697 231473 156549 GMT 1830 44167 30728 P75-LHRH 9 176 0 12177 5559 9 189 0 15795 17155 9 202 0 2121 2216 9 222 0 9787 7879 GMT 11201 8746
EXAMPLE 4
[0000] In Vitro T Cell Proliferation Assays to Demonstrate Recognition of Th-Epitope Incorporated in the Peptide Vaccines
[0090] To demonstrate recognition of the Th-epitope within the peptide immunogen PBMCs obtained from dogs immunised with peptide vaccines (dogs from Example 2) were tested against the respective Th-epitopes. The assay was carried out without the enrichment of PBMCs. PBMCs obtained from Ficoll gradient purification were directly tested against the respective Th-epitope and its truncated versions. The study demonstrated that all the dogs immunised with peptide vaccines responded to the Th-epitope incorporated confirming that T-cell activity resides in the respective sequences ( FIGS. 2-4 ). Truncated versions of the respective Th-epitopes were also tested to more closely define the T-cell activity within the sequences. It was observed that for P25 the full sequence of 17 residues was better than the shorter peptides of 15 and 12 residues, each truncated from the N-terminus of the sequence ( FIG. 2 ). This implies that the T-cell activity is towards the N-terminus or middle of the 17-residue peptide.
[0091] A similar observation was made with P27, the 17 residue long peptide was a better simulator than the 15-mer truncated from the N-terminus ( FIG. 3 ). This observation again suggested that the T-cell activity may reside towards the middle or the N-terminus of the full length peptide.
[0092] In the case of P35 and its shorter versions, except for one dog (#102), the other three dogs responded as well to the 12 residue peptide as to the full length 17 residue one ( FIG. 4 ). In dog # 102 the 15 residue peptide was more stimulatory than the full length peptide. From this it can be deduced that that the first two residues in the sequence of P35 may not be essential and that the activity is towards the middle or C-terminus of the peptide.
EXAMPLE 5
[0000] Trial in BALB/c Mice
[0093] The canine vaccines with CDV-F derived Th-epitopes and LHRH used in Example 3 were also used to immunise BALB/c mice to investigate if the Th-epitopes would be functional in a different animal species.
[0000] Vaccine Formulation
[0094] All vaccines were formulated as for Example 3 except that they were diluted further so that 100 μl doses contained 2.7 nmoles of peptide and 10 μg of Iscomatrix™ and thiomersol as preservative.
[0000] Vaccination, Blood Samples and Assays
[0095] Mice were vaccinated with 100 μl of the vaccine at the base of tail. Vaccinations were given at 0 and 4 weeks and animals bled at intervals after each vaccination from the retro-orbital plexus. Effective T-cell help was determined by measuring the antibody response to LHRH by ELISA.
[0000] Results
[0096] Mice immunised with P25-LHRH and pool of peptides comprising of P25-LHRH, P27-LHRH and P35-LHRH generated high antibody titres to LHRH. Peptides P35 and P75 generated low antibody titres whereas mice immunised P2, P8 and P62 had undetectable levels of anti-LHRH antibodies (Table 13).
[0097] It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.
TABLE 13 Anti-LHRH antibody titres in mice immunised with CDV-F derived T cell epitope-LHRH vaccines 4 weeks post first vaccination 2 weeks post second vaccination Groups Mouse 1 Mouse 2 Mouse 3 Mouse 4 Mouse 5 Mouse 1 Mouse 2 Mouse 3 Mouse 4 Mouse 5 Group <100 <100 <100 <100 1(control) Group 2 100 126 200 126 200 16,000 16,000 16,000 16,000 16,000 (pool) Group 3 126 400 282 100 282 16,000 16,000 16,000 16,000 16,000 (p25-LHRH) Group 5 <100 <100 <100 <100 <100 1,412 800 <100 <100 <100 (p35-LHRH) Group 6 <100 <100 <100 <100 (p2-LHRH) Group 7 <100 <100 <100 <100 <100 <100 <100 <100 (p8-LHRH Group 8 <100 <100 <100 126 126 <100 (p62-LHRH Group 9 <100 <100 <100 <100 <100 <100 <100 316 3,162 <100 (p75-LHRH
[0098] | The present invention provides T helper cell epitopes and compositions for use in inducing an immune response comprising at least one of these epitopes. The epitopes are contained within a peptide sequence selected from the group consisting of EPINQALTLMTKNVKPL (SEQ ID NO: 12); FAGVVLAGVALGVATAA (SEQ ID NO: 13); NLNAQAIQSLRTSLEQS (SEQ ID NO: 17) and TELLSIFGPSLRDPISA (SEQ ID NO: 20). | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a piping structure, an existing pipe cutting method and a fluid supply suspension free method.
2. Description of the Related Art
Existing running fluid pipes such as water pipes may possibly contain dirt or foreign substances such as sands, rust powders and metallic powders. Catching or collecting those foreign substances may therefore be indispensable. Such foreign substances have thus been collected and removed up until now. A known dirt collector is provided for example with a dirt reservoir expanding radially from the running fluid pipe body, the dirt reservoir having therein a meshed filter located at right angles to the axis of pipe (e.g., Japanese Patent Laid-open Pub. No. Hei7-136420).
Existing pipe lines have however often included sites free from such dirt collectors.
SUMMARY OF THE INVENTION
It is therefore the object of the present invention to provide a piping structure and so forth capable of collecting dirt or foreign substances without any suspension of the supply of a fluid such as water or oil.
In order to achieve the above object, according to a first aspect of the present invention there is provided a piping structure comprising an existing pipe and a seal-up housing. The existing pipe has a collection opening formed in the bottom thereof. The seal-up housing comprises two or more housing parts which are segmented in the circumferential direction of the existing pipe. The seal-up housing encloses a part of the existing pipe including the collection opening. One of the housing parts is formed with a collection space and a drain port. The collection space is adapted to collect dirt or foreign substances through the collection opening. The drain port communicates with the collection space, for discharging the dirt or foreign substances stored in the collection space.
In the piping structure of the present invention, the collection opening is most preferably an elongated cut groove which is formed in the axial direction of the existing pipe.
In order to form the cut groove, according to a second aspect of the present invention there is provided a method of cutting an existing pipe comprising an assembling step and a cutting step.
In the assembling step, the existing pipe is partially enclosed in a hermetically sealed manner by a seal-up housing consisting of a plurality of housing parts which are segmented in the circumferential direction of the existing pipe. A cutting unit having a cutting tool is mounted on the seal-up housing.
In the cutting step, the cutting tool is turned by the power of a prime mover so that the cutting tool can perform a cutting action for cutting the bottom of the existing pipe. The cutting step includes allowing a radial cut of the cutting tool into the existing pipe while turning the cutting tool to impart the cutting action to the same and includes displacing the seal-up housing in the axial direction of the existing pipe simultaneously with the cutting action. By imparting a feed action to the cutting tool through the axial movement of the seal-up housing in this manner, the existing pipe is cut by means of the cutting tool without creating any cut-off sections. The cutting tool thus forms an elongated rectilinear groove in the bottom of the existing pipe in the axial direction thereof.
In order to obtain the piping structure of the present invention, according to a third aspect of the present invention there is provided a fluid supply suspension-free method comprising an assembling step and a drilling step.
In the assembling step, an existing pipe is partially enclosed by a seal-up housing consisting of a plurality of housing parts which are segmented in the circumferential direction of the existing pipe. The seal-up housing is provided with a collection space and a drain port. The collection space is adapted to collect the dirt or foreign substances through a collection opening formed in the bottom of the existing pipe. The drain port is provided for discharging the dirt or foreign substances stored in the collection space.
In the drilling step, the collection opening is formed in the bottom of the existing pipe lying within the seal-up housing without any suspension of the fluid supply.
Any dirt or foreign substances residing within the existing pipe will migrate through the collection opening down into the collection space and collected therein.
According to a fourth aspect of the present invention there is provided a fluid supply suspension-free method preferably comprising an assembling step, a cutting step and a tool removal step which follow.
The operator first prepares a seal-up housing comprising two or more housing parts which are segmented in the circumferential direction of an existing pipe. One of the housing parts is previously provided with a collection space and a branching portion. The collection space is configured to be suited to collect dirt or foreign substances through a rectilinear groove formed in the bottom of the existing pipe. The branching portion is provided for allowing a cutting tool to advance or retreat (i.e., to cut into the existing pipe in the radial direction thereof).
In the assembling step, the existing pipe is partially enclosed by the seal-up housing in a hermetically sealed manner. A cutting unit having a cutting tool is mounted on the seal-up housing by way of an operation valve.
In the cutting step, the cutting tool is turned by the power of a prime mover so that the cutting tool can perform a cutting action for cutting the bottom of the existing pipe. The cutting step includes allowing a radial cut of the cutting tool into the existing pipe while turning the cutting tool to impart to the same the cutting action and includes displacing the seal-up housing in the axial direction of the existing pipe simultaneously with the cutting action. By imparting a feed action to the cutting tool through the axial movement of the seal-up housing in this manner, the existing pipe is cut by means of the cutting tool without creating any cut-off sections. The cutting tool thus forms an elongated rectilinear groove in the bottom of the existing pipe in the axial direction thereof.
In the tool removal step, the cutting tool is withdrawn from the branching portion after formation of the rectilinear groove.
Any dirt or foreign substances residing within the existing pipe will migrate through the rectilinear groove down into the collection space and collected therein.
The present invention enables a dirt collection apparatus to be mounted on the existing pipe without requiring any suspension in the fluid supply. Furthermore, any large-scale work will not be needed since the collection opening is formed in the bottom of the existing pipe in place of cutting off the existing pipe.
In particular, the present invention provides the collection opening in the form of an axially substantially elongated opening such as the cut groove elongated in the axial direction of the existing pipe, thereby preventing any dirt or foreign substances from jumping across the substantially elongated opening, to consequently achieve a secure collection of the dirt or foreign substances.
In the present invention, the “existing pipe” refers to a pipe through which flows a fluid such as water or oil and which is often situated under the ground.
The term “seal-up” does not mean completely sealing, but means keeping watertightness to such an extent that a work can be done without any suspension of the fluid supply. Therefore, the “seal-up housing” refers to a housing having a pressure resistance enough to resist the pressure of the fluid flowing through the existing pipe and having a certain level of water stop ability.
As used herein, “enclose something in a hermetically sealed manner” means sealing something to such an extent as not to hinder the cutting operation and so forth. For example, the drain port provided in the seal-up housing may remain opened during the cutting operation so that cutting chips can be discharged together with the fluid through the drain port.
The “cutting tool” for use in this method is preferably a milling-like tool whose tip surface and peripheral surface are each provided with a plurality of cutting edges.
In the event of cutting an existing pipe having a mortar lining formed on its inner surfaces, use is made preferably of a cutting tool provided with a multiplicity of hard metal chips or of a cutting tool having cutting edges made of grains of diamond.
In the present invention, “cutting” means removing a part of the pipe wall through turns of the cutting edges. As used herein, the “cutting action” means turning the cutting edges, whereas the “feed action” means moving the cutting tool to positions where virgin areas of the pipe wall can be cut in succession by the cutting tool.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal sectional view showing an assembling step of a method in accordance with a first embodiment of the present invention;
FIG. 2 is a sectional view taken along a line II—II of FIG. 1;
FIG. 3 is a longitudinal sectional view showing a cutting step;
FIG. 4 is a longitudinal sectional view showing a piping structure;
FIG. 5 is a longitudinal sectional view showing an assembling step in accordance with a second embodiment;
FIG. 6 .is a longitudinal sectional view showing a variant;
FIGS. 7 ( a ), 7 ( b ) and 7 ( c ) are bottom plan views each showing a variant of a collection opening;
FIG. 8 is a side elevational view partially in section showing a cutting unit by way of example; and
FIG. 9 ( a ) is a side elevational view showing an example of a cutting tool, and FIGS. 9 ( b ) and 9 ( c ) are perspective views of the same.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will become more apparent from the following detailed description of the preferred embodiments when taken in conjunction with the accompanying drawings. It is however to be noted that the embodiments and the drawings are shown for the illustrative purposes only and that the invention is delimited only by the appended claims. In the drawings attached, like reference numerals in a plurality of figures denote the same or corresponding parts.
The embodiments of present invention will now be described with reference to the drawings.
FIGS. 1 to 4 illustrate a first embodiment thereof.
Seal-up Housing 2
As illustrated in FIGS. 1 and 2, a seal-up housing is generally designated at 2 and comprises first and second housing parts 21 and 22 which are bisected in the circumferential direction of an existing pipe 1 . Rubber packings 26 are provided to hermetically seal the gap between the seal-up housing 2 and the existing pipe 1 and the connection between the first housing part 21 and the second housing part 22 as shown in FIG. 2 . The first housing part 21 serves to cover the existing pipe 1 from above, while the second housing part 22 serves to cover the existing pipe 1 from below.
The second housing part 22 is provided with a branching portion 27 and a dirt reservoir 28 which lie on a line extending in the axial direction S of the existing pipe 1 . The branching portion 27 protrudes in a branched manner downward in the radial direction C of the existing pipe 1 . A cutter case 31 of a cutting unit 3 is fixedly secured to the branching portion 27 by way of an operation gate valve 70 . Rubber rings not shown provide seals for any possible gaps between the branching portion 27 and the operation gate valve 70 as well as between the operation gate valve 70 and the cutter case 31 . The branching portion 27 is formed with an internally threaded portion 27 a into which a plug 60 of FIG. 4 is screwed.
The dirt reservoir 28 of FIG. 4 is tapered so as to be have a reduced diameter radially outwardly of the existing pipe 1 whereby there is formed a space suitable to store the dirt A. The dirt reservoir 28 has at its lower end a drain port 29 for discharging the dirt A stored. The drain port 29 is fitted with a discharge valve 30 which opens or closes for selective discharge of the dirt A. The discharge valve 30 is provided with a flexible horse not shown coupled thereto.
Cutting Unit 3
Referring back to FIG. 1 the cutting unit 3 comprises the cutter case 31 , a cutter rod 32 , a bearing portion 33 and a cutting tool 4 . The cutter rod 32 is coupled to a prime mover (e.g. , a motor) disposed outside of the cutter case 31 so that it is turned by power of the motor. One end of the cutter rod 32 is provided with the cutting tool 4 like an end mill, rigidly fastened thereto. The cutting tool 4 thus turns on the cutter rod 32 by power of the motor.
The cutter tool 4 includes a conically shaped tip surface 40 and a substantially cylindrical peripheral surface 41 , both the surfaces 40 and 41 having a multiplicity of cutting edges 42 thereon. The cutting tool 4 is housed in the cutter case 31 . It will be understood that this cutting unit 3 can be of the same structure as known drilling machines with the exception of its end mill shaped cutting tool 4 .
The method will be described hereinbelow.
Assembling Step
First, with liquid (water) flowing through the interior of the existing pipe 1 of FIG. 1, the seal-up housing 2 is mounted on the existing pipe 1 by an operator in such a manner that the branching portion 27 of the second housing part 22 is positioned upstream of the dirt reservoir 28 in the direction of flow F of the liquid (water). After this mounting, the first and second housing parts 21 , 22 are put together by the operator using assembly bolts not shown. The operation gate valve 70 and the cutting unit 3 are then fitted by the operator to the seal-up housing 2 . The existing pipe 1 is thus partially enclosed by the seal-up housing 2 in a hermetically sealed condition.
By means of setscrews 55 , a fixed plate 50 is then fixedly secured by the operator to the existing pipe 1 at a position apart from the seal-up housing 2 in the axial direction S of the existing pipe 1 . The position to fix the fixed plate 50 is determined depending on the length of grooves to be formed. A feed screw 51 is threaded into the fixed plate 50 so as to allow a displacement of the seal-up housing 2 in the axial direction S. One end of the feed screw 51 engages with the end portion of the seal-up housing 2 by way of a flange 52 . The feed screw 51 is thus turned counterclockwise by the operator in order that the seal-up housing 2 can be displaced rightward in the axial direction S.
Cutting Step
Following the assembling step, the branching portion 27 and the dirt reservoir 28 are positioned by the operator immediately under the existing pipe 1 . The cutting unit 3 is then operated by the operator so that the cutting tool 4 can rise up to a position at which the tip surface 40 of the cutting tool 4 is in close vicinity to the bottom surface of the existing pipe 1 . When the motor not shown is thereafter activated by the operator, the cutting tool 4 turns together with the cutter rod 32 to start a cutting action to cut the existing pipe 1 . During the cutting action, the operator acts on the cutting unit 3 so as to allow the cutting tool 4 to rise in the radial direction C, with the result that as indicated by a chain double-dashed line of FIG. 1 the tip surface 40 of the cutting tool 4 eventually penetrates a part of a pipe wall 1 a of the existing pipe 1 toward the center in the radial direction C. The infeed of the cutting tool 4 is thus completed.
After the completion of this infeed, the feed screw 51 is turned counterclockwise by the operator, whereupon the seal-up housing 2 is displaced toward the upstream (rightward) in the axial direction S so that it comes closer to the fixed plate 50 . With this displacement, the cutting tool 4 carrying out the cutting action performs a feed action for cutting the pipe wall 1 a . As a result, as illustrated in FIG. 3, an elongated rectilinear cut groove 12 C is formed in the axial direction S in the bottom of the existing pipe 1 without any cut-off sections created.
It is to be appreciated that the cut groove 12 C has a length enough to allow the dirt reservoir 28 to cover the downstream end of the cut groove 12 C.
Tool Removal Step
The cutting unit 3 is removed in accordance with a method described hereinbelow.
The cutting tool 4 is first housed in the cutter case 31 by the operator, after which an operation lever 71 of the operation gate valve 70 is acted upon so as to close the operation gate value 70 . The cutting unit 3 is then removed by the operator. After this removal, a known plug insertion machine not shown is fitted by the operator to the operation gate valve 70 , then the operation gate valve 70 is opened. Following this opening operation, the operator acts on the plug insertion machine not shown to screw the plug 60 of FIG. 4 into the internally threaded portion 27 a of the branching portion 27 . After this screwing operation, the operator removes the operation gate valve 70 (FIG. 3) and the plug insertion machine. The operation is thus completed and the piping structure of FIG. 4 is obtained.
Description will then be made in brief of a mechanism for collecting the dirt A.
The dirt A such as sands or metallic powders having a larger specific gravity than water is conveyed in the form of a flow rolling or jumping over the bottom of the existing pipe 1 . In this embodiment the dirt reservoir 28 is of greater dimensions in the axial direction S. This means that in spite of the flow of the dirt A in a jumping manner, the dirt A tends to migrate downward as indicated by the arrow of a chain double-dashed line of FIG. 4 . Therefore the dirt A can securely be collected. By opening the discharge valve 30 fitted to the drain port 29 , the dirt A collected within the dirt reservoir 28 is discharged together with water entraining the same.
It will be appreciated that since the dirt reservoir 28 is disposed downstream of the cutting unit 3 of FIG. 3 in the direction of flow F of the liquid (water), cutting chips which may occur during the cutting operation can also successfully be collected within the dirt reservoir 28 in the same manner with the formation of the cut groove 12 C.
Although in the first embodiment the cutting unit 3 has been positioned upstream of the dirt reservoir 28 in the direction of flow F of the liquid (water), the present invention will not necessarily be limited thereto. In the present invention, as seen in FIG. 5, the cutting unit 3 may be mounted on the drain port 29 of the dirt reservoir 28 (or on the branching portion 27 ) as long as it is capable of cutting the bottom of the existing pipe 1 . In this event, the operation gate valve 70 serves as the discharge valve without being dismounted therefrom after the operation.
Although in the first embodiment the elongated cut groove 12 C has been formed by use of the cutting tool 4 resembling the end mill, the present invention will not necessarily be limited thereto. For example, as can be seen in FIGS. 6 and 7 ( a ), circular openings 13 may be formed in immediate proximity to one another in the axial direction S of the existing pipe 1 by means of a known hole saw 14 . As seen in FIG. 7 ( b ), substantially circular openings 13 maybe formed in a continuous manner in the axial direction S of the existing pipe 1 . Furthermore, a single opening 13 may be provided as shown in FIG. 7 ( c ).
Reference is then made to FIG. 8 to describe a preferred example of the cutting unit 3 .
In the cutting unit 3 of FIG. 8, its cutter case 31 A is firmly fastened via an attachment 34 to the operation gate valve 70 (FIG. 1 ). An elongated cutter rod 32 extends through the interiors of a cutter case 31 A and a gear case 31 B. The cutter rod 32 is supported in a freely turnable manner by a first bearing 36 A and bearings not shown within the cutter case 31 A and the gear case 31 B. The cutter rod 32 is turned by the power of an electric motor (an example of the prime mover) 35 by way of reduction gears or bevel gears not shown.
An infeed screw 37 is provided in parallel with the cutter rod 32 within the cutter case 31 A. The infeed screw 37 is turned forwardly or reversely via bevel gears 39 A and 39 B by turning a handle 38 . The infeed screw 37 mates with an internally threaded portion formed in a hold 36 F. The hold 36 F serves to hold the cutter rod 32 by way of a second bearing 36 B. Thus, by turning the handle 38 , the infeed screw 37 turns so that the hold 36 F can advance or retreat, resulting in an advancement or retreat of the cutter rod 32 .
At the top of the cutter rod 32 is formed an internally threaded portion 32 f for threadedly receiving the cutting tool 4 .
Referring finally to FIGS. 9 ( a ) to 9 ( c ), a preferred example of the cutting tool 4 will hereinafter be described.
The cutting tool 4 comprises a tool body 43 to be fixedly screwed into the internally threaded portion 32 f (FIG. 8 ). First and second chips 44 A and 44 B are fitted via an externally threaded portion 45 to the tool body 43 in order to ensure that the chips 44 A and 44 B can be replaced with new ones when the cutting edge 42 has become abraded.
The first chips 44 A on one hand provide cutting edges 42 on the tip surface 40 of the substantially cylindrical tool body 43 and make cuts in the existing pipe 1 . The second chips 44 B on the other provide cutting edges 42 on the peripheral surface 41 of the substantially cylindrical tool body 43 and cut the existing pipe 1 . The chips 44 A and 44 B are preferably made of a hard metal. It is to be noted that the tool body 43 is formed with a large notch 43 a for the purpose of escaping cutting chips, in such a manner as to confront the first and second chips 44 A and 44 B.
While the preferred embodiments have been set forth hereinabove in the light of the drawings, it will easily be conceived by any persons with ordinary skill in the art to variously alter or modify the above embodiments from this specification without departing from the sprit or scope of the present invention.
By way of example, the prime mover conferring cutting actions on the cutting tool can be an engine in lieu of the motor. The cutting unit may be mounted on the seal-up housing, previous to the enclosure of the existing pipe by the seal-up housing.
The seal-up housing may be segmented circumferentially into three or four parts.
It will further be appreciated that the present invention encompasses oil or other liquid than water as the liquid flowing through the interior of the existing pipe.
Such variations and modifications are therefore to be construed as ones lying within the scope of the invention. | A piping structure of the present invention comprises an existing pipe and a seal-up housing. The existing pipe has a collection opening formed in the bottom thereof. The seal-up housing comprises two or more housing parts which are segmented circumferentially of the existing pipe. The seal-up housing encloses a part including the collection opening of the existing pipe. One of the housing parts is formed with a collection space and a drain port. The collection space serves to collect dirt or foreign substances through the collection opening. The drain port is provided for discharging the dirt or foreign substances stored in the collection space. | 8 |
BACKGROUND
This disclosure relates to a thrust chamber of a rocket engine system that allows higher energy from hydrocarbon fuels.
Bi-propellant rocket engines are known and used to power aerospace vehicles. A typical bi-propellant rocket engine can utilize an expander cycle. The expander cycle typically involves heating the fuel, which is then expanded over a turbine drive system to drive a propellant pump before delivery to the combustion chamber.
Typically, the expander cycle fuel is a light-molecule fuel, such as liquid hydrogen, methane or propane. The expander cycle fuel has a high specific heat that is advantageous to cooling the chamber and/or nozzle and providing the energy to power the propellant pumps. Heavier molecule hydrocarbon fuels have not found widespread use in expander cycle rocket engines because at high temperatures, heavier fuels tend to form coke deposits that block the passages and foul the system.
BRIEF DESCRIPTION OF THE DRAWINGS
The various features and advantages of the disclosed examples will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows.
FIG. 1 illustrates an example aerospace engine system.
FIG. 2 illustrates an example thrust chamber.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 schematically illustrates selected portions of a rocket engine system 22 . As will be described, the rocket engine system 22 is designed to allow the use of hydrocarbon fuels. Although depicted with a particular geometry and arrangement, it is to be understood that the concepts described herein are not limited to use with the specific rocket engine system 22 .
The illustrated rocket engine system 22 includes a thrust chamber 24 having walls 26 that define a combustion section 28 , a throat section 30 and a nozzle section 32 . In general, the combustion section 28 , the throat section 30 and the nozzle section 32 form an hourglass shape. That is, the combustion section 28 is relatively wide and narrows to the throat section 30 , which then widens to the nozzle section 32 . As shown, the nozzle section 32 is bell shaped.
The walls 26 of the thrust chamber 24 include cooling passages 34 therein. As shown in the illustration of the thrust chamber 24 in FIG. 2 , the walls 26 are constructed from tubes or passages arranged side-by-side to form the hourglass shape of the thrust chamber 24 . The interiors of the tubes or passages serve as the cooling passages 34 through which fuel flows to cool the thrust chamber 24 .
A fuel pump 36 in the rocket engine system 22 delivers fuel to the thrust chamber 24 . In that regard, a fuel passage 38 fluidly connects the thrust chamber 24 and the fuel pump 36 . The fuel passage 38 splits into sub-passages, with a first sub-passage 38 a leading to the combustion section 28 of the thrust chamber 24 and bypassing the cooling passage 34 . A second sub-passage 38 b leads to the cooling passage 34 of the thrust chamber 24 .
In embodiments, the second sub-passage 38 b continues on from the cooling passage 34 to a turbine 40 , which is coupled to drive the fuel pump 36 . From the turbine 40 , the second sub-passage 38 b leads to the combustion section 28 of the thrust chamber 24 . Alternatively, the fuel from the turbine 40 may be dumped overboard instead of going to the combustion section 28 . An additional pump 42 may also be coupled with the turbine 40 to deliver oxidizer to the combustion section 28 through an oxidizer passage 44 .
In embodiments, the cooling passage 34 may include a catalytic material 48 that chemically interacts with fuel flowing through the cooling passage 34 . The catalytic material 48 may be a catalytic coating that lines the interior walls of the cooling passage 34 . The catalytic coating composition and/or conditions within the cooling passages (pressure, temperature, etc) are established to provide an environment sufficient to sustain cracking of the hydrocarbon fuel selected. The condition and catalyst will vary depending on the hydrocarbon selected as well as pertinent engine and thrust chamber characteristics.
The arrangement of the rocket engine system 22 and thrust chamber 24 allows the use of hydrocarbon fuels, such as kerosene. As an example, kerosene can form coke deposits at the temperatures (approximately 1300.degree. F./704.degree. C. or greater) experienced in the cooling passages 34 of a conventional thrust chamber. However, controlling the fuel flow rate, pressure and/or temperature with the use of the catalytic material (not shown), a reduction of coking can be achieved. The reduced coking allows such fuels to be used as a propellant in the rocket engine system 22 without coke deposits that could otherwise block the fuel passages and foul the turbine. The cracking process itself is endothermic, and thereby improves the cooling capability of the hydrocarbon fuel to the advantage of the engine cycle, for example, enhanced cooling, energizing the fuel delivered to the turbine(s), and increasing the energy content of the fuel delivered to the thrust chamber.
In embodiments, the fuel is initially a liquid that is delivered through the fuel passage 38 from the fuel pump 36 . The split in the fuel passage 38 diverts a portion of the liquid fuel through the first sub-passage 38 a and another portion of the liquid fuel through the second sub-passage 38 b . The ratio of the flow split is determined to provide sufficient fuel to cool the thrust chamber while sustaining the conditions required for cracking the hydrocarbon fuel in the cooling passages 34 .
Optionally, a flow splitter 50 is provided within the fuel passage 38 to control the split of flow of the fuel. In that regard, a controller 52 in communication with the flow splitter 50 may command the flow splitter 50 to control the ratio of flow to each sub-passage 38 a , 38 b . The controller 52 may also be in communication with the other control valves as desired to control rocket engine system 22 .
With the split in the fuel passage 38 , only a portion of the fuel flows through the cooling passage 34 , while the other portion flows directly to the combustion section 28 . By controlling the amount of fuel that flows through the cooling passage 34 , the controller 52 can ensure that the fuel in the cooling passage 34 heats to a predetermined temperature to sustain steady-state cracking of the hydrocarbon fuel in the cooling passages 34 prior to injection into the turbine 40 . That is, by reducing the amount of fuel delivered to the cooling passage 34 , the fuel flowing through the cooling passages 34 can be sustained above a critical temperature in a steady state operating condition for cracking and subsequent expansion in the turbine 40 to drive the fuel pump 36 .
Additionally, the catalytic material 48 within the cooling passage 34 serves to crack the heated fuel into lighter molecules thereby reduce coking of the fuel. Furthermore, the chemical cracking of the fuel is an endothermic reaction that absorbs additional heat from the thrust chamber 24 . Also, the conversion of the fuel into lighter molecules facilitates converting the fuel into a gaseous state for expansion over the turbine 40 . The rocket engine system 22 thereby allows the use of relatively heavy hydrocarbon fuels, such as kerosene. The fuel thereby serves the dual purposes of cooling the thrust chamber 24 and driving the turbine 40 .
Although a combination of features is shown in the illustrated examples, not all of them need to be combined to realize the benefits of various embodiments of this disclosure. In other words, a system designed according to an embodiment of this disclosure will not necessarily include all of the features shown in any one of the Figures or all of the portions schematically shown in the Figures. Moreover, selected features of one example embodiment may be combined with selected features of other example embodiments.
The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this disclosure. The scope of legal protection given to this disclosure can only be determined by studying the following claims. | An engine system includes a thrust chamber that has a cooling channel. The cooling channel is adapted to provide sustained cracking conditions for a fluid at steady-state operating conditions. A turbine has an input in fluid communication with an output of the cooling channel. A pump is mechanically coupled with the turbine and is in fluid communication with the cooling channel. | 5 |
BACKGROUND OF THE INVENTION
In a wide variety of application, there exists the need for products which will thicken or gel organic solvent based formulations. There also is a need for products to be used in the areas of organic-water system applications as gelling materials therefor.
Previous developments of Teng et al (one of the present inventors) have shown that esters of hydroxypropyl cellulose and starch are useful as gelling agents for organic solvents.
In Teng et al U.S. Pat. No. 3,730,693 are disclosed lipophilic polymeric carbohydrate derivatives as gelling agents, specifically cellulose laurate and starch laurate.
In Teng et al U.S. Pat. No. 3,870,701 are disclosed benzyl hydroxypropyl cellulose acetate gelling agents and Teng et al Ser. No. 387,894 filed Aug. 13, 1973, now U.S. Pat. No. 3,940,384, discloses methyl hydroxypropyl cellulose acetates as gelling agents.
Teng et al U.S. Pat. No. 3,824,085 discloses methods for producing acetate esters of hydroxypropyl cellulose which are effective gelling agents for a series of commercially important solvents. One of the reactants required for production of these esters is acetic anhydride. Because of the low yield of the acetylation reaction, it is desirable to find a reactant that has a higher percentage conversion than acetic anhdyride.
We have developed another series of effective gelling agents; namely, methyl hydroxpropyl cellulose ethers (MHPC) having a degree of substitution (D.S.) of methyl groups of 1.0 to 2.4 and a degree of molar substitution (M.S.) of hydroxypropyl groups of 2 to 8. We have found that methyl hydroxypropyl cellulose ethers gel a larger variety of organic solvents than do the acetate esters of hydroxypropyl cellulose.
The purpose of the following paragraph is to explain the use herein of the terms degree of substitution (D.S.) and degree of molar substitution (M.S.).
The degree of substitution is defined as the average number of hydroxyl groups substituted per anhydroglucose unit. The maximum number of hydroxyl groups per anhydroglucose unit is three, and therefore the theoretical maximum degree of substitution is also three in the case of monofunctional substituents. In the case of polyfunctional or polymerizable substitutents that can react not only with the hydroxyl groups of the polysaccharide but also with themselves, the number of substituents is no longer limited by the three available hydroxyl groups on the anhydroglucose unit. The term degree of molar substitution, (M.S.), is adopted and defined simply as the number of moles of substituent per anhydroglucose unit. There is no theoretical maximum value for the degree of molar substitution, (M.S.).
Methyl hydroxypropyl cellulose ethers have been synthesized by the hydroxypropylation of cellulose, followed by a methylation step. Although methyl hydroxypropyl cellulose ethers are disclosed in U.S. Pat. No. 2,831,852, the methyl hydroxypropyl cellulose ethers of the present invention are clearly distinguishable from those of U.S. Pat. No. 2,831,852 due to the different M.S. of hydroxypropyl groups and D.S. of methyl groups. Furthermore, methyl hydroxypropyl cellulose ethers of the present invention show solubility and gelling characteristics that are not possible with those of the methyl hydroxypropyl cellulose ethers of U.S. Pat. No. 2,831,852 when combined in organic solvents.
A comparison of certain of the chemical and physical properties of the methyl hydroxypropyl cellulose ethers of U.S. Pat. No. 2,831,852 and the methyl hydroxypropyl cellulose ethers of the present invention are shown in the following Table I.
TABLE I__________________________________________________________________________ Solubility M.S. of D.S. Of Carbon Hydroxypropyl Methyl Tetra- Group Group Water chloride Toluene__________________________________________________________________________Methyl hydroxy-propyl celluloseether of Pat. No. clear insol- insol-2,831,852 0.3-1 1.5-2.0 gel uble ubleMethyl hydroxy-propyl celluloseethers of present cloudy clear clearinvention 2-8 1.0-2.4 metastable gel gel gel__________________________________________________________________________
These gelling agents provide many desirable properties which are lacking in the presently available gelling agents. Generally, methyl hydroxypropyl cellulose ethers display greater clarity in gelling solutions than do hydroxypropyl cellulose acetates. Methyl hydroxypropyl cellulose ethers also gel with solvent-water mixtures, whereas hydroxypropyl cellulose acetates do not. Methyl hydroxypropyl cellulose ethers can gel the widest range of diverse solvents as listed in Table I. Furthermore, the ether linkages of methyl hydroxypropyl cellulose ethers are more stable to alkali, acid, and water than the ester linkages of hydroxypropyl cellulose acetates.
The preparation of these materials is economical, based on both material and processing costs. The reactions are run under mild conditions with no special equipment required except a pressure reactor. The reactants include cellulose, sodium hydroxide, propylene oxide, and methyl chloride (or methyl bromide or dimethyl sulfate). The use of methyl chloride is most desirable in that it is practical and efficient. Any of a number of inert solvents may be used, e.g., toluene, hexane, dimethyl formamide, dioxane. Hexane is preferred for the reason that product recovery is simplified.
The products of this invention are lipophilic polymers capable of thickening or gelling a wide variety of solvents.
Examples of solvents which are capable of being gelled with methyl hydroxypropyl cellulose ethers are seen in Table II. These organic solvents may be esters, ketones, aromatic hydrocarbons, nitriles, amides, alcohols or halogenated solvents with a solubility parameter of about 8 to about 16.
The solubility parameter is a measure of the compatibility of solutes with solvents and its definition and determinations are set forth in Polymer Handbook, edited by E. H. Immergut, Interscience Publishers (1966). The solubility parameter, "δ," is a thermodynamic property of solvents. Thermodynamic calculations show that when a solute is mixed with a solvent of equal solubility parameter, spontaneous dissolution takes place. Once the value for a given polymer is determined, it is known that other solvents with comparable values will also dissolve it.
The term solubility as used in this context has a somewhat different meaning than when it is used conventionally. Solubility is used generally to indicate the extent of interaction between a solid and a solvent. A piece of solid, when placed in a solvent, will dissolve into the solvent until the saturation point is reached. At that point, the two phases, solid and liquid, coexist at equilibrium. The amount of solute in liquid is measured as the solubility of the material in solution. However, in polymers and particularly in the case of the gelling agent of this invention, there is no obvious saturation point. When immersed in a `compatible` solvent, the gelling agents swell and dissolve. When the solvent concentration is high, a polymer solution forms; when the solvent concentration is low only swelling and hence gelling occurs. An apparent single phase (solution or gel) is reached at all times. To examine qualitatively the compatibility of a gelling agent with a solvent, 5 grams of gelling agent is placed in 100 ml. of solvent. If only one phase is observed (gel or solution) they are compatible. When the mixture retains two phases, they are incompatible.
Table II shows examples of solvents with their corresponding solubility parameters. The methyl hydroxypropyl cellulose ethers gel solvents with solubility parameters of 8 to 16.
TABLE II______________________________________Solvents Solubility Parameter______________________________________ethyl acetate 8.4carbon tetrachloride 8.4toluene 8.9methyl ethyl ketone 9.3dioxane 10.3pyridine 10.3acetonitrile 11.5dimethyl formamide 12.1methanol 14.5methyl formamide 16.1______________________________________
We have found that methyl hydroxypropyl cellulose ethers are particularly useful in gelling or thickening organic solvents at concentrations from 0.4 to 5% (W/W). The gelling agents of this invention are soluble in a wide range of organic solvents and water solvent mixtures, and are effective thickeners or gellants at 1% concentrations.
Solutions and gels may be prepared by simple agitation and heating.
SUMMARY OF THE INVENTION
This invention comprises a process of preparing methyl hydroxypropyl cellulose ethers by reaction of alkali cellulose with propylene oxide and subsequent reaction with methyl chloride to produce products with molar substitution (M.S.) of hydroxypropyl groups of about 2 to about 8 and degree of substitution (D.S.) of methyl groups of about 1.0 to about 2.4. These cellulose ethers gel organic solvents, such as toluene, carbon tetrachloride, ethyl acetate, dioxane.
They also gel solvent-water mixtures. They can be used as emulsifiers in organic-water solvent systems.
DETAILED DESCRIPTION
From about 40 to about 45 grams cellulose is made alkaline in about 0.5 to about 1 liter of an organic solvent. Suitable solvents are toluene, hexane, and dimethyl formamide, with toluene preferred because uniform product is prepared from this reaction medium. The alkali cellulose mixture is reacted with 40 to 300 grams propylene oxide in a pressure vessel at a pressure of 15 to 30 psi. The vessel is heated for 5 to 7 hours at temperatures ranging from about 65° C. to 110° C. After the hydroxypropylation is completed to a M.S. of 0.5 to 7.0 the remaining solvent is decanted. The crude hydroxypropyl cellulose is methylated by adding 20 to 200 grams sodium hydroxide, 18 to 180 grams water, 40 to 400 grams methyl chloride and 0.5 to 1.0 liter hexane or other suitable solvent. The reaction is carried out at 40° C. to 75° C. for about 1 to 4 hours. When the degree of substitution of methyl group is 1.0 to 2.4, the excess solvent is removed. The methyl hydroxypropyl cellulose product is slurried in warm water and the pH of the slurry is adjusted to 7.0. The product is washed with warm water and then dried.
The amount of methyl hydroxypropyl cellulose ether required for gelling purposes is at least about 0.5 grams per 100 ml. of solvent and may be as much as about 20 grams per 100 ml. The amount generally used is 2 grams per 100 ml. solvent to be gelled.
The final gel has a specific gravity approximating that of the solvent.
The methyl hydroxypropyl cellulose dispersion is allowed to stand and achieve maximum solvation to complete gelation of thickening.
Table III shows the gelling properties of methyl hydroxypropyl cellulose ethers and hydroxypropyl cellulose acetates (U.S. Pat. No. 3,824,085)in various organic solvents, water, and mixtures consisting of organic solvents and water.
TABLE III__________________________________________________________________________ Methyl Hydroxypropyl Hydroxypropyl Cellulose Cellulose Ethers AcetatesSolvent (D.S. 1.0-2.4; M.S. 2-8) (D.S. 1.0-2.0; M.S. 2-8)__________________________________________________________________________Propyleneglycol clear gel insolubleToluene clear gel clear gelCarbonTetra-chloride clear gel clear gelEthylacetate clear gel hazy gelDioxane clear gel very slight hazy gelDimethylformamide clear gel clear gelPyridine clear gel clear gelMethyl ethylKetone clear gel slightly hazy gelAcetonitrile very slightly hazy gel hazy gelHexane insoluble insolubleWater-Ethanol Mixtures10% water-90% Ethanol clear gel clear gel20% water-80% Ethanol clear gel hazy gel40% water-60% Ethanol clear gel insoluble60% water-40% Ethanol hazy gel insoluble100% water cloudy metastable gel insoluble__________________________________________________________________________
EXAMPLE 1
In this example, 21 g. of 23.8% aqueous NaOH solution was added to 40 g. shredded cellulose and 470 ml. toluene, and the resulting mixture was stirred for 45 minutes at 25° C. The alkali cellulose mixture was then placed in a pressure vessel along with 160 ml. of propylene oxide. (The air in the vessel was purged with nitrogen at 70 psi three times). The vessel was then heated at 65° C. for 1/2 hour, 75° C. for 1 hour, 85° C. for 1 hour, and 95° C. for 3 hours. At the end of this period, the hydroxypropylation reaction was substantially complete. The hydroxypropyl cellulose had M.S. about 4.
The solvent toluene (280) ml.) was decanted. The crude hydroxypropyl cellulose was then methylated by adding 49 g. of NaOH, 22 g. of water, 210 g. of methyl chloride and 400 ml. hexane. The reaction was carried out at 60° C. for 1 hour and 70° C. for 3 hours.
Upon completion of the reaction, the excess methyl chloride (140 g.) was recovered by dissolving in hexane and cooling with methanol and dry ice. The methyl hydroxypropyl cellulose product was slurried in warm water (60° C).
The slurry was kept acidic by addition of small amounts of acetic acid. The pH of the slurry was finally adjusted to 7.0.
The product was washed with warmer water three times and dried at 70° C. The product had a D.S. of about 2.5.
EXAMPLE 2
A slurry of 50 g. of finely cut cellulose in 500 g. of hexane, 10 ml. of water and 6 g. of NaOH was stirred for 1 hour at 25° C. This alkali cellulose was added to a pressure reactor along with 150 g. of propylene oxide and 40 g. of methyl bromide. The air was purged from the reactor with nitrogen. The resulting charge was heated to 75° C. in 30 minutes and then reacted at this temperature for 1 hour, at 85° C. for 1 hour, and at 95° C. for 4 hours. At this stage, a small amount of product was purified by washing with hot water (85°-90° C.) and neutralized with acetic acid. The product had M.S. of 5.0 and D.S. of 0.5 The Brookfield viscosity of a 1% aqueous solution of the product at 25° C. was 2100 cps.
Upon completion of the hydroxypropylation, this crude methyl hydroxypropyl cellulose ether was directly reacted with 400 g. of methyl bromide along with 55 g. of NaOH and 25 ml. of water. The methylation was carried out at 70° C. for 4 hours the resulting solid product was then washed with warm water. The slurry was kept acidic to phenolphthalein by addition of acetic acid in small amounts as needed. The pH of the slurry was finally adjusted to 7.0. The product was washed substantially free of salt impurities with warm water (60° C.); the water was then decanted and the product dried at 100° C. The resulting product had D.S. of 2.8.
EXAMPLE 3
This example differs primarily from the foregoing Examples in that dimethyl sulfate is used as the methylating agent.
A slurry of 20 g. cellulose pulp in 200 g. of toluene and 20 g. of 33% aqueous NaOH solution was stirred in a reaction vessel which was immersed in an ice bath (0°-5° C). After the slurry had been stirred for 1 hour at this temperature, the resulting alkali cellulose was reacted with 90 g. of propylene oxide at 85° C. for 11/2 hours and at 95° C. for 4 hours.
After hydroxypropylation was complete the solvent toluene was removed by filtration from the resulting hydroxypropyl cellulose product. This hydroxypropyl cellulose filter cake was broken up and added to a pressure reactor along with 120 g. of dimethyl sulfate and 200 g. of hexane. The resulting mixture was heated at 70° C. for 5 hours. The methyl hydroxypropyl cellulose product was a solid suspended in the hexane.
The solvent hexane was removed by filtration and the filter cake was slurried in warm water (60° C). The methyl hydroxypropyl cellulose ether was recovered, purified and dried as in Example 2. The product has a M.S. of 3.8 and D.S. of 1.5
EXAMPLE 4
40 g. of cellulose, 14 g. of 25% aqueous NaOH solution and 600 ml. of toluene were mixed at 4° C. for one hour in a 2-liter pressure reactor. The air was purged from the reactor with nitrogen. Then 160 ml. of propylene oxide was added to the reaction vessel. The reactor was heated to 75° C. within 1 hour, then to 85° C. within 1 hour, and finally to 95° C. within 1 more hour. At this stage, the heating was discontinued and the solvent toluene was decanted.
This crude hydroxypropyl cellulose was then reacted with 150 g. of methyl chloride along with 60 g. of 60% aqueous NaOH solution and 500 ml. of hexane. The methylation was carried out at 70° C. for 2 hours.
Thereafter the methyl hydroxypropyl cellulose ether was purified as in Example 2. The resulting product has a M.S. of 2.5 and D.S. of 2.0.
EXAMPLE 5
40 g. of cellulose, 16 g. of 25% aqueous NaOH solution, and 500 ml. of toluene were mixed at 25° C for 2 hours in a pressure reactor. The air was purged from the reactor with nitrogen. Then 300 ml. of propylene oxide was added to the reaction vessel. The reactor was heated to 75° C within 1 hour, then to 85° C. within 1 hour, and finally to 95° C. within 1 more hour. The reactor was maintained at 95° C. for 4 hours. At this stage, the heating was discontinued and the solvent toluene was decanted.
This crude hydroxypropyl cellulose was reacted with 140 g. of methyl chloride and 60 g. of 50% aqueous NaOH solution and 600 ml. of hexane. The methylation was conducted at 75° C. for 31/2 hours.
Thereafter the methyl hydroxypropyl cellulose ether was purified as in Example 2. The resulting product has a M.S. of 8.1 and D.S. of 1.8 | This disclosure relates to the production of methyl hydroxypropyl cellulose ethers having a degree of molar substitution (M.S.) of greater than 2. The methyl hydroxypropyl cellulose ethers are prepared at low cost under mild conditions and are particularly useful in gelling organic solvents having a solubility parameter of 8 - 16. They also have compatibility for mixtures of organic solvents and water and are helpful in gelling such solutions when the percentage of water in such mixtures is up to about 60%. | 2 |
This application is a continuation of U.S. patent application Ser. No. 09/820,041, filed Mar. 28, 2001, now U.S. Pat. No. 6,454,511, which is a division of patent application Ser. No. 09/388,181, filed Sep. 1, 1999, now U.S. Pat. No. 6,439,826, which is a continuation-in-part of patent application No. 09/168,358, filed Oct. 7, 1998, now U.S. Pat. No. 6,431,816, which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
The present invention relates to improvements in fluid power load-clamping systems for variably regulating maximum load gripping forces in a manner automatically adaptive to at least one characteristic of the load.
Various types of such adaptive load-clamping systems have been proposed in the past. Such previous systems can be categorized as follows:
(1) Systems which sense the existence of load slippage and respond automatically by gradually increasing the gripping force on the load by fixed force increments until the sensed slippage stops;
(2) Systems which automatically vary the gripping force in proportion either to the sensed weight or to the resistance to gripping of the load, without regard to whether or not slippage is actually occurring; and
(3) Systems which perform a combination of (1) and (2).
Fluid power clamping systems of any of the above types regulate gripping force by gradually increasing gripping fluid pressure automatically from a relatively low threshold pressure. However such low threshold pressure limits the speed with which the load-engaging surfaces can be closed into initial contact with the load, thereby limiting the productivity of the load-clamping system. This problem occurs because high-speed closure requires higher closing pressures than the desired low threshold pressure, such higher pressures becoming trapped in the system by fluid input check valves during initial closure so that the desired lower threshold pressure is exceeded before automatic regulation of gripping pressure can begin. Although gripping pressure relief valve systems have in the past provided high and low relief settings selectable either manually, or automatically in response to clamp closure speed, to enable high-speed closure followed by low maximum gripping pressure, no such systems capable of automatically changing such settings in a manner compatible with automatic variable gripping pressure regulation have been known.
Prior fluid power systems such as those disclosed in British Patent Publication No. 2312417 and German Patent Publication No. 3245715, which vary the gripping fluid pressure in proportion to the sensed weight of the load, obtain weight measurements by lifting the load. However such weight-sensing systems operate only in response to clamp closure actuation, and therefore do not continue to vary the gripping fluid pressure in proportion to load weight during subsequent manipulation of the load in the absence of continued clamp closure actuation. Furthermore, such prior systems do not weigh the load in response to lifting of the load by tilting which, in paper roll handling operations, is a commonly-used alternative way to lift the load. The system shown in the British publication is also susceptible to inaccurate weight measurements due to variations in lifting pressure which are inherent within the extensible lifting mechanism depending upon its degree of extension.
Such prior weight-responsive systems also do not provide for different selectable predetermined relationships between the weight of the load and the gripping pressure, which are needed to account for variations in load fragility and stability.
Although automatic load tilt adjustment systems have been provided in the past for leveling fragile loads to prevent edge damage when the load is being set down, such automatic adjustment systems have not been capable of sensing the tilt of the load with respect to gravity, leading to inaccurate automatic tilt adjustment depending on whether or not an industrial lift truck is level with respect to its supporting surface, or whether or not such surface is level.
Valves for automatically preventing excessive lowering of the lifting mechanism when a clamped load is set down, to prevent subsequent damage to fragile load surfaces by downward slippage of the clamp when it is opened to disengage the load, have been provided in the past as shown, for example, in U.S. Pat. No. 3,438,308. However, such previous systems lack the versatility needed for reliable protection of the load under variable circumstances, such as variations in the degree of extension of the lifting mechanism when the load is set down.
BRIEF SUMMARY OF THE INVENTION
In one preferred aspect of the invention, a controller automatically enables high initial clamp closure speed prior to automatic gripping pressure regulation by initially permitting relatively high fluid pressure to close the clamp, followed by an automatic reduction in the maximum fluid pressure as the clamping surfaces close into a predetermined relationship with the load, followed by an increase in the maximum fluid pressure pursuant to automatic maximum gripping pressure regulation.
In another separate preferred aspect of the invention, the load-weight measurement is compensated to account for variations in extension of the lifting mechanism, also to maximize the accuracy of the load-weight measurement.
In another separate preferred aspect of the invention, automatic weight-responsive gripping pressure regulation is operable without concurrent clamp closure actuation.
In another separate preferred aspect of the invention, automatic weight-responsive gripping pressure regulation is operable in response to lifting of the load solely by tilting.
In another separate preferred aspect of the invention, different predetermined relationships between the weight of the load and the maximum gripping pressure are selectable alternatively.
In another separate preferred aspect of the invention, a gravity-referenced tilt controller automatically adjusts the load to an attitude which is untilted with respect to gravity.
In another separate preferred aspect of the invention, an improved system is provided for automatically preventing further lowering of the lifting mechanism when the load is set-down.
In another separate preferred aspect of the invention, the speed of lowering of the lifting mechanism is limited automatically to aid the accuracy of the lowering prevention system.
The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a front view of an exemplary embodiment of a fluid-powered load-handling clamp in accordance with the present invention.
FIG. 2 is a top view of the load-handling clamp of FIG. 1 .
FIG. 3 is a schematic diagram of an exemplary electrohydraulic circuit for the clamp of FIG. 1 .
FIGS. 4A-4F are an exemplary simplified logic flow diagram of an initialization sequence, a load clamping sequence, and a disengagement sequence utilized by the microprocessor-based controller in the circuit of FIG. 3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An exemplary embodiment of a load-handling clamp in accordance with the present invention is indicated generally as 10 in FIGS. 1 and 2 . The exemplary clamp 10 is a hydraulically-powered, pivoted-arm clamp having a base 15 adapted for mounting on a lift truck carriage which is selectively reciprocated linearly along an upright hydraulically-powered load-lifting mast indicated schematically as 11 in FIG. 3 . The mast is selectively tiltable forwardly and rearwardly by a pair of tilt cylinders such as 13 in FIG. 3 . The particular clamp 10 depicted in-the drawings is for handling large paper rolls such as 12 in FIG. 2 used in the publishing and paper industries which, if deformed excessively as a result of overclamping to prevent slippage, will become too distorted for use on the high-speed printing presses or other machinery for which they are intended. On the other hand, under-clamping can cause the paper roll 12 to slip from the frictional grasp of the clamp 10 , particularly when the load-engaging surfaces 14 and 16 of the clamp 10 are oriented vertically by the clamp's rotator 18 which rotates the respective clamp arms 20 and 22 relative to the base frame 15 about an axis 24 (FIG. 2 ). Although the hydraulically-operated paper roll clamp 10 is described herein as the preferred embodiment, the present invention is also applicable to many other types of load clamps. For example, clamps in accordance with the present invention could alternatively have sliding rather than pivoted arms, and could handle rectilinear rather than round loads.
Each of the clamp arms 20 and 22 is rotatable about its respective pivot pins 26 , 28 selectively toward or away from the other clamp arm by the selective extension or retraction of respective pairs of hydraulic cylinders 30 and 32 associated with the respective arms 20 and 22 . The cylinders 30 which actuate the shorter clamp arm 20 are primarily used only to position the clamp arm 20 in advance for carrying rolls 12 of different diameters and different desired lateral positions. Therefore, closure of the clamp arms and their load-engaging surfaces to grip the load is normally accomplished solely by movement of the clamp arm 22 in response to extension of the cylinders 32 . In some clamps, the shorter clamp arm 20 could be fixed, and the cylinders 30 eliminated. In other clamps, particularly those with sliding arms, closure would normally be accomplished by moving both clamp arms simultaneously toward each other. Moreover, closure may be caused by retraction of cylinders instead of extension thereof.
With reference to FIG. 3 , hydraulic clamping cylinders 32 are controlled through hydraulic circuitry indicated generally as 34 to receive pressurized hydraulic fluid from the lift truck's reservoir 38 through a pump 40 and supply conduits 42 and 43 . Safety relief valve 44 opens to shunt fluid back to the reservoir 38 if excessive pressure develops in the system.
A priority flow control valve 49 insures that a predetermined priority flow, for example one gallon per minute, of fluid is diverted to conduit 43 before excess flow is permitted to conduit 42 . The priority flow in conduit 43 is for automatic gripping pressure regulation, while the excess flow in conduit 42 supplies manually actuated load-clamping and hoisting selector valves 36 and 80 respectively, as well as a tilt control valve 82 .
The clamp control valve 36 is controlled selectively by the operator to cause the cylinders 32 to open the clamp arms and to close the clamp arms into initial contact with the load 12 . To open the clamp arms, the spool of the valve 36 is moved downwardly in FIG. 3 so that pressurized fluid from line 42 is conducted through line 46 to the rod ends of cylinders 32 , thereby retracting the cylinders 32 and moving the clamp arm 22 away from the clamp arm 20 . Pilot-operated check valves 50 are opened by the pressure in line 46 communicated through pilot line 52 , enabling fluid to be exhausted from the piston ends of cylinders 32 through line 54 and valve 36 to the reservoir 38 as the cylinders 32 retract. Alternatively, to close the clamp arms, the spool of the valve 36 is moved upwardly in FIG. 3 so that pressurized fluid from line 42 is conducted through line 54 to the piston ends of cylinders 32 , thereby extending the cylinders 32 and moving the clamp arm 22 toward the clamp arm 20 . Fluid is exhausted from the rod ends of the cylinders 32 to the reservoir through line 46 via the valve 36 .
During closure of the clamp arms by extension of the cylinders 32 , the maximum closing pressure in the line 54 is preferably regulated by a pilot controlled modulating pressure regulator valve assembly 75 of which the pilot control is by variably controlled relief valve assembly 74 . The variable relief valve assembly 74 preferably comprises a single relief valve whose relief setting is infinitely proportional to a variable signal received from the controller 70 through signal line 76 . Alternatively, the maximum closing pressure could be regulated by single or multiple relief valve and/or regulator valve assemblies with different settings automatically selectable by a signal from the controller 70 , or by an automatically-variable pressure-reducing valve assembly having one or more pressure-reducing valves in series with line 54 whose output pressure settings are variably regulated by the controller 70 .
As the clamp arms are closed toward the load, the controller 70 operates in accordance with the steps of FIGS. 4C-4E , and in accordance with the initialization values previously entered into the controller 70 by the operator pursuant to FIGS. 4A and 4B using keyboard switches such as 118 . Appropriate portions of these figures will be referenced in the following operational description of the clamp.
During initial clamp arm closure, the controller 70 sets the variable relief pressure of the valve assembly 74 , as indicated at step 200 of FIG. 4C , at a relatively high level previously selected by the operator at step 300 of the initialization sequence of FIG. 4B from among three alternative levels “1, 2, 3.” Such pressure level enables high-speed closure of the clamp arms toward the load prior to actually gripping the load. Thereafter, in response to contact of the load-engaging surfaces of-the clamp arms with the load, the clamp-closing pressure in line 54 as sensed by pressure sensor 78 increases above a minimum pilot pressure level previously selected by the operator at step 315 . At the same time the volumetric flow rate in line 54 decreases and causes a corresponding decrease in the positive differential, between the pressure reading by the pressure sensor 78 and the reading by the pressure sensor 66 , to a differential value below that previously selected by the operator at step 301 of the initialization sequence of FIG. 4 B. In response to such changes, reflecting a predetermined resistance by the load to further closure of the arms, the controller 70 at steps 202 and 204 of FIG. 4C immediately reduces the relief setting of the relief valve assembly 74 to a relatively low threshold level previously selected by the operator from among three alternatives at step 302 of FIG. 4 B. This decreases the pressure, between the pilot-operated check valves 50 and the cylinders 32 , to the reduced relief setting so that the high-speed initial closing pressure is not maintained between the check valves 50 and the cylinders 32 . Such reduced pressure is the threshold gripping pressure from which subsequent increases in gripping pressure will be automatically regulated as described below.
Instead of reducing the closing pressure in response to load resistance as described, other predetermined relationships between the load and the load-engaging surfaces could trigger the pressure reduction, such as a predetermined proximity therebetween.
After the desired threshold gripping pressure is established at step 204 , the operator moves the valve 36 to its centered, unactuated position and begins to lift the load, either by manually actuating the hoist-control valve 80 to move the load linearly upward, or by manually actuating the tilt control valve 82 to tilt the load rearwardly.
In the case of the hoist valve 80 , its spool is moved upwardly to lift the load and downwardly to lower the load as seen in FIG. 3 . When the valve 80 is actuated to lift the load, the valve 80 conducts pressurized fluid from line 42 through lines 84 and 88 to the base of one or more hoist cylinders, schematically indicated as 90 , of the mast 11 . A pressure sensor 92 senses a resultant increase in pressure in line 88 and signals the controller 70 that lifting has begun, as indicated at step 206 of FIG. 4 C. In response, the controller actuates solenoid valve 94 , as indicated at step 208 of FIG. 4D , by moving its spool upwardly in FIG. 3 so that the priority flow in line 43 can flow through line 54 to the cylinders 32 to further close the clamp arms.
The controller 70 senses the magnitude of the weight of the load through the signal from the pressure sensor 92 , and adjusts the relief setting of the valve assembly 74 upwardly in a predetermined relation to the sensed magnitude of the load weight in a manner to be explained more fully hereafter. Since solenoid valve 94 is actuated, this increases the maximum fluid gripping pressure in line 54 in a predetermined relation to the magnitude of the load weight. The cushioning effect of accumulator 87 minimizes dynamic effects on the load-weight measurement and thereby maximizes the accuracy of such measurement. If necessary, a restrictor (not shown) in the line 88 can be optionally included to limit lifting speed and thereby further minimize dynamic effects.
After the foregoing maximum fluid gripping pressure has been achieved, the controller 70 deactivates the solenoid valve 94 as indicated at step 212 of FIG. 4E , moving the spool of the valve downward in FIG. 3 so that automatic gripping pressure regulation ceases. The valve 74 is set by the controller 70 to prevent any further gripping pressure increases which might otherwise result from the operator's manipulation of valve 36 , as indicated by step 214 in FIG. 4 E. Thereafter, the system begins continuous monitoring of the fluid gripping pressure relative to the sensed load weight and, if necessary, readjusts the gripping pressure as explained more fully hereafter.
Alternatively, the operator's manual actuation of the tilt control valve 82 to tilt the load rearwardly and thus lift it, by moving the spool upwardly in FIG. 3 , also initiates the foregoing load-weighing and pressure-regulating operation in the same manner, since the pressure sensor 92 will sense a resultant increase in pressure in line 88 due to the lifting of the load and will initiate the above-described sequence beginning with step 206 .
It will be recognized that sensors other than fluid pressure sensors 66 , 78 and 92 could be used. For example, flow meters and/or electromechanical force sensors could be substituted as appropriate.
During the above described load-weighing and pressure-regulating operation, increased fluid gripping pressure causes some extension of the clamping cylinders 32 , requiring the exhaust of some fluid through line 46 from the rod ends of the cylinders 32 . Since the clamp control valve 36 would normally be centered during such operation, such fluid is exhausted to the reservoir 38 through a parallel line 48 and pilot operated check valve 58 which is opened by the pressure in line 54 transmitted through pilot line 60 .
The accuracy of the load-weight measurement is enhanced by compensating for variations in extension of the mast 11 which vary the pressure reading of the sensor 92 . Such pressure variations can result from multiple causes, such as changes in effective pressure areas of the hoist cylinder or cylinders 90 , or the fact that telescopic sections of the mast 11 may or may not be supported by the hoist cylinder or cylinders 90 , depending upon whether the mast is in its lower “freelift” range of extension or in its higher “mainlift” range of extension. To account for these variables, as well as variables in the load-handling clamps that might be mounted interchangeably on the mast, the controller 70 is initialized according to FIGS. 4A and 4B to calibrate the load-weighing system with respect to such variables. Such initialization includes reading and storing the respective pressures sensed by the sensor 92 in both the freelift and mainlift ranges of extension of the mast while dynamically lifting the load-handling clamp, both without a load as shown in steps 304 and 306 of FIG. 4A to obtain P f and P m respectively, and with a load of known weight as shown in steps 308 and 310 to obtain P fw and P ms respectively. The controller 70 also reads respective pressures P fs and P ms sensed by sensor 92 with no load in the freelift and mainlift ranges, respectively, under static conditions, i.e. in the absence of dynamic lifting, and stores the pressures as indicated at steps 313 and 314 of FIG. 4 B. Furthermore, the controller stores the known load weight W k as indicated at step 312 in response to operator entry using keyboard switches such as 118 . Other operator entries using keyboard switches include one or more desired clamp-force-to-load-weight ratios CF/W ratio 1, 2, 3, as indicated at step 316 , and a “clamp factor” X at step 320 representing the total effective pressure area of the combined clamping cylinders 32 multiplied by the efficiency percentage of the clamp cylinders 32 . Such efficiency percentage corresponds to the ratio of the clamp force generated by the load-engaging surfaces 16 (after frictional and other mechanical losses) to the product of the effective pressure area of the combined clamping cylinders 32 and the applied fluid pressure.
As indicated at step 324 at the beginning of the initialization process of FIG. 4A , all of the foregoing parameters need be entered only for new installations or changes of load-handling clamps or masts. Otherwise, only the shorter list of entries designated as “Option 2 ” in FIG. 4 need be entered, or no entries if the operator does not wish to change any listed parameter.
Returning to the load-clamping sequence of FIGS. 4C-4E , the controller 70 controls the load-weight measurement and gripping pressure regulation processes by automatically accounting for the range of extension of the mast 11 (freelift or mainlift), different desired clamp-force-to-load-weight ratios, and the other variables mentioned in connection with FIGS. 4A and 4B . Immediately after clamp pressure is relieved at step 204 of FIG. 4C , the controller senses at step 218 whether a mechanical switch 219 , responsive to the degree of extension of the mast 11 , is closed. If the switch is closed, the controller 70 determines at step 218 that the mast is in its lower, or freelift, range of extension; otherwise the controller determines that the mast is in its higher, or mainlift, range of extension. Depending on such determination, the controller 70 sets the future load-weight calculation with parameters appropriate either for the freelift range of extension or the mainlift range of extension of the mast. After the actuation of solenoid 94 at step 208 in response to the operator's lifting of the load by actuation of the hoist valve 80 or the tilt valve 82 as previously described, the controller reads the lifting pressure P sensed by pressure sensor 92 as indicated at step 220 , and at step 222 calculates therefrom the load weight W using the appropriate freelift or mainlift calculation.
For the freelift range of extension of the mast 11 , the calculation is as follows:
W = ( P - P f ) ( W k ) ( P fw - P f )
For the mainlift range of extension of the mast 11 , the calculation is as follows:
W = ( P - P m ) ( W k ) ( P mw - P m )
In the foregoing calculations, P f and P m are the values which were previously entered during steps 304 and 306 , respectively, of the initialization sequence of FIG. 4A , while P fw and P mw are the values previously entered during steps 308 and 310 . W k is the weight of the known load used during initialization and previously entered at step 312 of the initialization sequence.
After calculation of the load weight W at step 222 of FIG. 4D , the controller determines which predetermined clamp-force-to-load-weight ratio CF/W was previously selected by the operator at step 316 of FIG. 4B , and determines at step 224 of FIG. 4E the desired maximum clamp force CF by the equation:
CF=W ( CF/W ).
Having determined the desired maximum clamp force CF at step 224 , the controller 70 determines the clamp factor X previously entered by the operator at step 320 and calculates the maximum fluid gripping pressure CP at step 226 by the equation:
CP=CF/X.
At step 228 the controller then adjusts the maximum pressure relief setting of valve 74 to the desired maximum fluid gripping pressure CP. This process repeats continuously until the controller determines that the actual fluid gripping pressure sensed by sensor 66 equals or exceeds the desired fluid gripping pressure CP, as indicated at step 230 . The controller 74 then deactivates the solenoid 94 at step 212 and sets the valve 74 at step 214 to prevent manually activated pressure increases as described previously.
Instead of manual keyboard selections of different clamp-force-to-load-weight ratios at step 316 of FIG. 4B , or different initial threshold gripping pressures at step 302 , different relationships between maximum gripping pressure and load weight to account for differences in fragility or stability of the load can be selected automatically in response to an electronic code reader 120 which senses characteristics of a load by reading a coded label on the load. Such variable relationships can also be selected automatically by a proximity sensor 122 which senses the distance between the load-engaging surfaces of the clamp arms to determine the size of the load being gripped. Accordingly, different types of predetermined relationships between fluid gripping pressure and load characteristics are contemplated by the present invention, as well as different types of mechanisms for selecting such different relationships.
After initial automatic regulation of the gripping pressure during initial clamp closure, the system continually senses whether the clamped load is being supported by the clamp by comparing the hoist pressure sensed by sensor 92 with the appropriate unloaded static hoist pressure P fs or P ms previously stored at steps 313 and 314 , depending on whether the switch 219 is closed, as indicated at step 240 . As long as the hoist pressure at sensor 92 is greater than the appropriate stored unloaded static hoist pressure, indicating at step 242 of FIG. 4F that the operator has not set the load down, the system repeatedly recalculates the desired fluid gripping pressure CP as before, and compares it to the actual fluid gripping pressure at sensor 66 . In the comparison at step 244 , the system determines whether the actual fluid gripping pressure is at least a predetermined percentage (such as 95%) of what it should be. If not, the system automatically readjusts the relief setting of the valve assembly 74 upwardly to the new desired maximum fluid gripping pressure CP and readjusts the fluid gripping pressure and resultant gripping force, beginning at step 218 of FIG. 4C , by recalculating the gripping pressure CP and reactivating the solenoid valve 94 . On the other hand, if the actual fluid gripping pressure is still within the predetermined percentage at step 244 , the controller merely continues to recalculate and compare the actual fluid gripping pressure, without also readjusting it. This automatic repetitive monitoring and correction of the fluid gripping pressure and resultant gripping force corrects for such variables as leakage in the clamp cylinders 32 which could decrease the gripping force, or the possibility that the load was not fully supported by the clamp during the initial automatic regulation of the gripping pressure. The priority flow from the priority flow control valve 49 , and the parallel exhaust line 48 , insure the reliability of the continuous gripping-force correction feature, even though the clamp control valve 36 is in its centered, unactuated condition.
The foregoing repetitive monitoring and, if necessary, correction operation continues until the system senses, at step 242 of FIG. 4F , that the operator has set the load down. Thereafter, once the operator has opened the clamp, as sensed at step 232 by a pressure rise at sensor 98 , the load clamping sequence returns to its origin at step 200 of FIG. 4C where the relief pressure of valve 74 is reset at the relatively high level needed for high speed closure, as described previously.
To minimize the possibility of setting a fragile load down onto a supporting surface in a tilted attitude such that the edge of the load would be damaged, a gravity-referenced tilt sensor 124 is optionally mounted on the base frame 15 of the clamp 10 to determine whether or not the load is tilted forwardly or rearwardly with respect to gravity and to cause the controller 70 to automatically adjust the load to a level attitude by corrective solenoid actuation of the tilt control valve 82 . Mounting the gravity-referenced tilt sensor 124 on the clamp structure, rather than on the mast 11 , allows the sensor to determine whether or not the load is tilted with respect to gravity irrespective of any tilting of the mast 11 due to mast deflection or other factors. The gravity-referenced sensor is also independent of whether or not the lift truck is level with respect to its supporting surface, or whether or not such surface is level. However, despite its foregoing advantages, the gravity-referenced sensor 124 is also susceptible to instability and long settling times if subjected to dynamic disturbances during lift truck travel, such as acceleration or braking, or vertical dynamic disturbances caused by ramps or uneven surfaces. For this reason, the controller 70 actuates the tilt control valve 82 correctively only in response to a decrease in load-weight detected by pressure sensor 92 (i.e. a negative pressure slope) in response to lowering of the load by the mast 11 to set the load down. During such lowering of the load, dynamic disturbances are minimized due to stoppage of the lift truck.
Another problem which can lead to load damage while setting the load down onto a supporting surface is the possibility that the operator may continue to lower the mast 11 after the load has been set down but before the operator has opened the clamp arms. In such case, the chains of the mast which normally support the clamp will become slack because the clamp is then supported by the clamped load rather than the mast. Thereafter, when the operator finally opens the clamp arms to disengage the load, the load engaging surfaces of the clamp arms slide down the surfaces of the load, causing external damage to fragile loads such as paper rolls. To minimize the possibility of such damage a solenoid valve 47 downstream of a priority flow control valve 45 is preferably provided so as to be automatically controlled by the controller 70 , in response to the setting down of a clamped load, to prevent further lowering of the mast until after the clamp arms have been opened to disengage the load. In the normal lowering mode, fluid flows through the priority path of the priority flow control valve 45 , and flows through conduit 84 and hoist control valve 80 , in its lowering position, through line 56 to the reservoir 38 . The priority flow control valve 45 is of a design where the priority flow requirements must be satisfied before the valve will permit any flow to bypass through its excess flow port and the excess flow conduit 51 . With reference to FIG. 4E , when the controller 70 detects through sensor 92 at step 240 that the hoist pressure has declined to a level equal to or less than the unloaded static pressure P fs or P ms , this indicates that a clamped load has been set down on a supporting surface. Accordingly, pursuant to step 242 of FIG. 4F the controller 70 activates the solenoid valve 47 at step 236 thereby blocking the priority flow path. Without the priority flow condition being fulfilled, the priority flow control valve 45 blocks excess flow from returning to the reservoir alternatively through conduit 51 and thereby prevents the mast from lowering further. When the clamp is subsequently opened, as automatically determined at step 232 by sensing a pressure rise at sensor 98 , the controller deactivates the solenoid valve 47 at step 238 , and the mast and clamp can thereafter be further lowered by the operator without damaging the load. During lowering of the mast 11 , an optional restrictor 55 can be employed to limit lowering speed to maintain the accuracy of the pressure sensed by sensor 92 even if the operator opens the lowering control valve rapidly and fully. The foregoing lowering prevention system is also applicable to other types of loads and load-engaging structures, such as forks, to prevent free-fall of the load-engaging structure when disengaged from the load.
The foregoing lowering prevention system can alternatively be implemented without the priority flow control valve 45 and excess flow conduit 51 by employing a solenoid valve 47 capable of a larger volumetric flow rate.
The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow. | A fluid power load-clamping system includes at least one fluid valve for variably regulating the maximum fluid pressure causing closure of the clamp. Preferably the valve increases the maximum fluid pressure automatically in relation to the measured magnitude of the weight of the load to regulate the load-gripping force. A controller causes the valve to permit a relatively high maximum fluid pressure as the clamp closes toward the load to enable high initial clamp closure speed. Thereafter the valve automatically reduces the maximum pressure as the clamping surfaces close into a predetermined relationship with the load, and then increases the maximum pressure to regulate the gripping force. Other preferable features include continuous weight-responsive automatic regulation of the gripping pressure while the load is supported by the clamp, and compensation of the weight measurement for the longitudinally-extensible position of the lifting mechanism, to maximize the accuracy of the load-weight measurement. Gripping pressure regulation is operable in response to linear load-lifting or tilting load-lifting, without concurrent clamp closure actuation. Different predetermined relationships between the weight of the load and the maximum gripping pressure are selectable alternatively. A gravity-referenced tilt controller adjusts the load automatically to an attitude which is untilted with respect to gravity. Lowering of the lifting mechanism is automatically prevented in response to the setting down of the load. | 8 |
This application claims priority to British Application Number GB0009792.3 filed on Apr. 25, 2000.
BACKGROUND OF THE INVENTION
The present invention relates to the provision of arcuate drive means within a motor vehicle aperture closure such as a vehicle side passenger door, boot lid, sun roof and the like.
It is increasingly common for motor vehicles to be provided with electric motors housed within the door assemblies thereof. Typically a vehicle door may be provided with a motor adapted to raise and lower a window glass panel, a motor to drive central locking means of the door, and a further motor to enable security locking or deadlocking of the door. More expensive vehicles may have doors provided with additional motors to enable, for example, automatic closing thereof.
The plurality of motors described above increases both the weight and complexity of a door and a corresponding increases manufacturing costs.
SUMMARY OF INVENTION
According to the present invention there is provided a drive system operable to drive vehicle aperture closure functions comprising a drive actuator operably connected to a drive member, the drive member having at least first and second positions and being movable between the first and second positions, operation of the drive actuator when the drive member is in the first position causing operation of an aperture closure function.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the present invention will now be described with reference to the accompanying drawings in which:
FIG. 1 shows a diagrammatic plan view of a drive system according to the present invention;
FIG. 1A shows diagrammatic plan view of another drive system according to the present invention.
FIG. 2 shows the cross-sectional view indicated by arrows 2 — 2 in FIG. 1 . Image Page 2
FIG. 3 shows an alternative cross-sectional profile for a driveshaft for use in the embodiment shown in FIG. 1 .
FIG. 4 shows a schematic isometric view of a vehicle including a drive system according to the present invention, and
FIG. 5 shows an isometric schematic view of a further vehicle including a drive system according to the present invention.
FIG. 6 shows functions of a drive system according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2 there is shown a drive system, generally designated 10 for a vehicle door assembly. The drive system 10 comprises a drive actuator in the form of a main motor 12 having a drive shaft 14 extending therefrom, a stepper motor 16 having a threaded shaft 18 extending therefrom, a drive member 20 slidably mounted on the drive shaft 14 , and a yoke 22 mounted on the threaded shaft 18 . The drive system 10 further includes a plurality of rockers 24 pivotably mounted to a rocker shaft 26 and a window regulator shaft 28 provided substantially co-axially with respect to the drive shaft 14 . The rockers 26 are movable to operate door functions, such as locking functions, via link members 50 . The main motor 12 and stepper motor 16 are electric motors.
The stepper motor 16 , threaded shaft 18 and yoke 22 together form a selector actuator.
As can be seen from FIG. 2, the drive shaft 14 is substantially square in cross-section and is received in a correspondingly shaped aperture 30 of the drive member 20 . The drive member 20 has the general form of a disc and is provided with abutment surfaces 32 , 34 adapted to, in use, engage an engagement portion 36 of respective rockers 24 . In the embodiment shown the abutment surfaces 32 , 34 are defined at opposing sides of a recessed portion 38 of the peripheral edge 40 of the drive member 20 .
The yoke 22 is provided with a slot 41 within which the drive member 20 is received. A threaded aperture 42 in the base 44 of the yoke 22 is adapted to receive the threaded shaft 18 and hence enable the yoke 22 to be driven by the stepper motor 16 .
The drive member 20 is further provided with drive teeth 46 which are adapted to engage corresponding drive teeth 48 provided on the window regulator shaft 28 .
Operation of the drive system 10 is as follows. The stepper motor 16 is operated to rotate the threaded shaft 18 and, via the threaded connection therebetween, move the yoke 22 with respect to the threaded shaft 18 . Movement of the yoke 22 results in corresponding movement of the drive member 20 relative to the drive shaft. Taking the example where it is desired to carry out a locking function via one of the rockers 24 , the stepper motor 16 is operated to move the drive member 20 into position relative to the appropriate rocker 24 . Once in position the stepper motor 16 ceases operation so as to maintain the drive member 20 in the correct position with respect to the rocker 24 .
The drive motor 12 is then operated to rotate the drive shaft 14 and drive member 20 and move one of the drive member abutment surfaces 34 , 32 into engagement with the rocker engagement portion 36 . Continued rotation of the drive member 20 causes pivotal movement of the rocker 24 about the rocker shaft 26 and hence executes the locking function.
Alternatively the drive system 10 may be operated so as to raise or lower a window. In such an operative mode, the stepper motor 16 is driven so as to move the drive teeth 46 of the drive member 20 into engagement with the drive teeth 48 of the window regulator shaft 28 . Once these teeth 46 , 48 are engaged the drive motor 12 is operated to rotate the window regulator shaft 28 .
Furthermore it is possible to provide a neutral position of the drive system. Such a position is shown in FIG. 1 wherein the drive member (shown dotted) is positioned adjacent the drive motor such that operation of the drive motor does not cause operation of any door function. Such a position can usefully be included to provided additional safety features such that inadvertent operation of the drive motor 12 does not, for example, cause opening or unlocking of a door.
In further embodiments stepper motor 16 can be replaced by a DC motor or any other suitable power source. In particular where the motor is a DC motor it is advantageous for the drive member 20 to only have a first and second position.
As shown in FIG. 1A, in further embodiments it is not necessary to provide the selector actuator (i.e., stepper motor 16 , threaded shaft 18 and yolk 22 ) since this function can be performed manually. Such an arrangement is particularly advantageous where only a limited number of door functions are required to be performed by the drive actuator for example where the drive actuator operates raising and lowering of a window glass and also operates to close and/or release the door.
In a further embodiment the selector actuator may be arranged to move the drive actuator and the drive member together as a whole.
FIG. 3 shows an alternative cross-section profile for a driveshaft 114 for use in the embodiment shown in FIG. 1 . In is case drive shaft 114 is of the Torques™ profile being smoothly contoured and multilobed.
FIG. 4 shows a vehicle 100 including various aperture closures, in particular hood 101 , trunk 102 , sunroof 103 , front side passenger door 104 and rear side passenger door 105 . Passenger doors 104 and 105 are pivotally mounted, in this case at a front edge. The aperture closures can include a drive system according to the present invention.
FIG. 5 shows a vehicle 110 with various aperture closures, in particular a side passenger door 111 which slides to open, a tailgate 112 and a rear window 113 .
Sliding door 111 includes a drive system according to the present invention.
Tailgate 112 can be pivoted downwards about pivots 114 and rear window 113 can be pivoted upwards about pivots 115 . In particular it can be seen that the window 113 has a lower edge 113 A which closes against an upper edge 112 A of tailgate 112 . A drive system according to the present invention is mounted in tailgate 112 and interacts with rear window 113 . In particular the drive system in tailgate 112 can be used to lock rear window 113 in a closed position. Alternatively or additionally the drive system mounted in tailgate 112 can be used to drive wiper blade 116 , which is mounted on rear window 113 . Alternatively or additionally the drive system mounted in tailgate 112 can be used to power a washer pump also mounted on tailgate 112 which squirts water onto rear window 113 .
It can be seen that in this case the function provided by the drive system on tailgate 112 interacts with the adjacent rear window 113 .
FIG. 6 shows schematically functions actuable with drive system 10 . | A drive system ( 10 ) operable to drive vehicle door functions comprises a drive member ( 20 ) mounted for rotation about a drive axis by a drive motor ( 12 ), a rocker ( 24 ) operable by the drive member ( 20 ), and translation means ( 16 ), ( 18 ), ( 22 ) operable to move the drive member ( 20 ) to a predetermined position on the drive axis. | 4 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates to cylinder locks and, in particular, it concerns a cylinder lock apparatus that can be operated with or without a key.
In a conventional mechanical cylinder lock, when an appropriate matching key is inserted into the cylinder lock, the key serves to mechanically align tumbler pins, and thereby allowing the cylindrical plug to be rotated freely to open the lock. Referring now to FIGS. 1A and 1 . B, which are representations of a prior art cylinder lock 10 , with a key 12 inserted into the cylinder lock, and a door lock 15 . Door lock 15 includes, inter alia, a shaped slot 16 for receiving cylinder lock 10 and a door lock bolt hole 17 through which a bolt (not shown) is inserted to secure the cylinder lock inside a door. Typically, door lock 15 is inserted into a hollowed-out edge of the door (not shown) and cylinder lock 10 is inserted through prepared holes in the door (not shown in the figure) and perpendicularly into and through shaped slot 16 , substantially along axis 18 . Door lock further comprises a locking tongue 19 . Typically, cylinder lock 10 , when unlocked, serves to translate locking tongue 19 allowing the tongue to alternately inhibit and allow opening of the door. Typically, other cylinder locks having a cross-sectional profile and length substantially matching cylinder lock 10 may be replaced or retrofitted instead of cylinder lock 10 . Typical names/manufacturers of such cylinder locks include, but are not limited to: Euro Cylinders; Oval Cylinders; Asec 6-pin Euro profile; and Chubb M3. Overall lengths of such cylinders typically vary from approximately 70-95 mm.
Reference is now made to FIGS. 2A and 2B , which are cross sectional side views A-A of the cylinder lock shown in FIG. 1A . The cylinder lock has a body housing 20 , which is bored from one end to the other end and a cylindrical plug 22 , which is fitted into the bore, and which may be rotated, as described hereinbelow. A set hole 23 is located approximately in the middle of cylinder lock 10 to receive a bolt which is inserted into door lock bolt hole 17 , to secure the cylinder lock within door lock 15 , as described hereinabove in FIG. 1B . Cylindrical plug 22 has a key slot 25 formed axially in cylindrical plug. Key 12 is inserted into slot 25 . A pin-tumbler set 30 is located in body housing 20 and in cylindrical plug 22 to serve to lock and unlock rotational movement of cylindrical plug 22 . Cylindrical plug 22 and a second cylindrical plug 31 may be mechanically coupled and uncoupled to a rotating tongue 35 by means of a selector mechanism (not shown in the figure), which allows either cylindrical plugs to rotate the rotating tongue, which in turn serves to move the locking tongue of the door lock (refer to FIG. 1B ). The cylinder lock shown in FIGS. 2A and 2B is called a “blind cylinder”, meaning that a key can be inserted into only one side of the lock, with only one pin-tumbler set present, and that the other side of lock cannot accept a key. However, cylinder lock 10 may also comprise pin-tumbler sets in respective cylindrical plugs at both ends.
FIG. 2B , which is a detailed view of FIG. 2A , shows in greater detail pin-tumbler set 30 . Pin-tumbler set 30 includes tumbler pins 32 and driver pins 34 , both of which are constrained to move generally perpendicularly to key 12 . Springs 33 typically serve to preload the driver pins and the tumbler pins, displacing them towards slot 25 , thereby advancing part of one or more of driver pins 34 into cylindrical plug 22 through openings in the plug (not shown in the figure) and thereby locking rotation of cylindrical plug 22 when no key is present in the slot. Typically, key 12 is formed to fit the pattern and respective lengths of tumbler pins 32 . When key 12 is fully inserted into slot 25 , the key presses tumbler pins 32 and driver pins 34 against springs 33 , alignedly inserting driver pins 34 into body housing 20 , and thereby enables rotation of the cylindrical plug. Whereas key 12 is shown inserted, with its wider traverse edge contacting the tumbler pins, another inserted orientation of key 12 may include its thinner traverse edge contacting the tumbler pins. Also, one or more additional sets of collinearly arranged tumbler pins (not shown) may be present, in the case of a master key, which is used to lock and unlock a number of such specially configured cylinder locks.
A number of prior art electronic or combination electrical/mechanical lock systems allow a user to open a locked cylinder in a number of ways. In U.S. Pat. No. 3,889,501 by Fort, whose disclosure is incorporated herein by reference, a combination electrical and mechanical system is described. The system includes a lock having a fixed lock cylinder and a rotatable key slug. A first solenoid is employed in the current system to drive a lock pin, which is normally extended to lock the key slug. Upon insertion of an appropriately aperture-encoded key, light sources and detectors mounted in the lock are used in concert with appropriate circuitry to operate to the first solenoid to unlock key slug. A second solenoid is operable, in response to an electrical power failure, to extend a latch pin. When the latch pin is extended a proper mechanical key is inserted and rotated, extension of the lock pin is prevented. A proper mechanical key can be inserted to move a plurality of spring loaded pin tumblers in the lock to enable rotation of the key slug during an electrical power failure.
Aston, in U.S. Pat. No. 5,839,305 whose disclosure is incorporated herein by reference, discloses an electrically operable cylinder lock device, which includes a body with a bore housing a rotatable barrel, having a key slot. The device has an electromagnet, which is employed to interact with a detent bar, the detent bar positioned to alternately inhibit or enable, with the aid of the electromagnet, rotation of the rotatable barrel. Another embodiment disclosed by Aston has a microswitch which interacts with an inserted key and controls the supply of electrical power.
While the prior art includes an array of combination electrical/mechanical lock systems of varying complexity, there is a need for an electronic or combination electrical/mechanical cylinder lock that, taking advantage of the inherent cylinder pin tumbler mechanism, can be unlocked or unlocked without the insertion of a key, while also functioning as a conventional lock operated with a key in case of an electrical power failure.
SUMMARY OF THE INVENTION
The present invention is a combined electrical/mechanical cylinder lock that, taking advantage of the inherent pin tumbler mechanism, can be unlocked or unlocked without the insertion of a key, while also functioning as a conventional lock operated with a key in case of an electrical power failure.
According to the teachings of the present invention there is provided, a cylinder lock device including: a body housing having a bore, with a direction of elongation defining an axial direction for the device; a rotatable cylindrical plug in the bore, the plug having an axially extending key slot from at least one end of the plug; a plurality of driver pins configurable substantially perpendicular to the key slot and located within the body housing and substantially outside of the plug; a plurality of tumbler pins corresponding to and positionable substantially collinear with each one of the plurality of driver pins and substantially inside the plug, the tumbler pins displaceable by a key to bias the driver pins to enable rotation of the plug, the driver pins adapted to displace the respective tumbler pins; and a displacement mechanism being deployed within the body housing and adapted to displace the plurality of driver pins thereby selectively enabling rotation of the plug when no key is present in the slot.
Most preferably, the key slot extends substantially radially to the side of the plug, forming a lateral opening in the plug and wherein the cylinder lock further comprises a fitted inhibitor adapted to cover the lateral opening so that the plurality of displacer pins do not enter the lateral opening and thereby do not serve to inhibit disruption of rotation of the rotatable cylindrical plug. Preferably, the displacement mechanism is adapted to controllably displace the plurality of driver pins between a first state in which the plurality of driver pins are biased towards the key slot to provide a locked state and a second state in which the plurality of driver pins are aligned to allow rotation of the cylindrical plug.
Typically, the displacement mechanism includes a first artificial muscle unit adapted to selectively displace the respective plurality of driver pins. Preferably, the displacement mechanism includes an electromagnetic assembly, wherein the electromagnetic assembly comprises a controllable magnetic pole configuration to selectively displace the respective plurality of driver pins to allow the respective plurality of driver pins to be selectively displaced. Typically, the displacement mechanism includes a magnetic unit, wherein the magnet unit includes a magnetic pole configuration to allow the respective plurality of driver pins to be selectively displaced. Most preferably, the displacement mechanism includes a mechanical linkage, the mechanical linkage driven by a linkage driver selected from the group consisting of: a second artificial muscle unit; a linear motor assembly, a rotational motor assembly, and an electromagnetic assembly.
Most preferably, a rotatable tongue is positionable substantially axially with and at the interior end of the first rotatable plug and having an axial engager enabling the rotatable tongue to rotate with the first plug; a second rotatable cylindrical plug is in the bore, the axial engager enabling the rotatable tongue to rotate with the second plug; and a selector mechanism is adapted to selectively engage and disengage the axial engager when a key is present in the slot and when no key is present in the slot, the selector mechanism being adapted to preferentially engage the axial engager, enabling the rotatable tongue to rotate with the first plug. Preferably, the selector mechanism is further adapted to engage the axial engagement and to rotate the first plug when a key is present in the slot, after the rotatable tongue has been rotated by the second plug. Typically, the selector mechanism is mechanically, electrically, and mechanically and electrically actuable. Most typically, the body housing dimensions are substantially identical to at least one of the following cylinder lock standards: Euro Cylinder; Oval Cylinder; Asec 6-pin Euro profile; and Chubb M3.
There is further provided a cylinder lock device including a body housing having a bore, with a direction of elongation defining an axial direction for the device; a rotatable cylindrical plug in the bore, the plug having an axially extending key slot from at least one end of the plug; and a mechanically accessible handle permanently mechanically linked to the plug at the end of the plug having the slot, the handle adapted to rotate the plug when the plug is freed to rotate and when no key is present in the slot. Most preferably, the handle is adapted to allow insertion and removal of a key from the slot. Preferably, the handle is further adapted to be hinged, so that the handle is stowed substantially perpendicular to axis of the plug and deployed substantially parallel to the axis of the plug.
There is further provided a method of forming a cylinder lock device comprising the steps of: forming a bore in a body housing of the cylinder lock device, the body housing having a direction of elongation defining an axial direction for the device; inserting a rotatable cylindrical plug in the bore, the plug having an axially extending key slot from at least one end of the plug; configuring a plurality of tumbler pins in the plug, whereby a key displaces the tumbler pins to enable rotation of the plug; positioning a plurality of driver pins, corresponding to and substantially collinear with each one of the plurality of tumbler pins and locatable distally from the slot and from the plurality of tumbler pins, adapted to displace the respective tumbler pins; and deploying a displacement mechanism within the body housing to displace the plurality of driver pins thereby enabling or disabling rotation of the plug when no key is present in the slot. Most preferably, the method further includes the steps of: positioning a rotatable tongue substantially axially with and at the interior end of the first rotatable plug, and having an axial engager enabling the rotatable tongue to rotate with the first plug; inserting a second rotatable cylindrical plug in the bore, the axial engager enabling the rotatable tongue to rotate with the second plug; and configuring a selector mechanism to selectively engage and disengage the axial engager when a key is present in the slot and when no key is present in the slot, the selector mechanism preferentially engaging the axial engager, enabling the rotatable tongue to rotate with the first plug.
There is further provided a method of forming a cylinder lock device comprising the steps of: forming a bore in a body housing of the cylinder lock device, the body housing having a direction of elongation defining an axial direction for the device; inserting a rotatable cylindrical plug in the bore, the plug having an axially extending key slot from at least one end of the plug; and configuring a mechanically accessible handle permanently mechanically linked to the plug at the end of the plug having the slot, whereby the handle serves to rotate the plug when the lock is unlocked and when no key is present in the slot.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
FIGS. 1A and 1B are representations of a prior art cylinder lock and a door lock, respectively;
FIGS. 2A and 213 are cross sectional side views of the cylinder lock shown in FIGS. 1A and 113 ;
FIG. 3 is an end view and a cross sectional view of a cylinder lock with magnetic displacement of the pin-tumbler set, in accordance with of an embodiment of the present invention;
FIG. 4 is an end view and a cross sectional view of the cylinder lock of FIG. 3 with magnetic displacement of the pin-tumbler set, in accordance with an embodiment of the present invention;
FIGS. 5A and 5B are end and cross sectional views, respectively of the cylinder lock of FIG. 3 , with artificial muscle displacement of the pin-tumbler set showing an unlocked and locked state, respectively, in accordance with an embodiment of the present invention;
FIGS. 6A-C are cross-sectional, representative, and cross sectional views, respectively, of the cylinder lock of FIG. 3 , having a mechanical linkage assembly displacement of the pin-tumblers and having a cylindrical plug rotational handle, in accordance with embodiments of the present invention;
FIGS. 7A and 7B are schematic illustrations of a modified cylindrical plug and the key, in accordance with an embodiment of the present invention;
FIGS. 8A-F are schematic illustrations of exemplary configurations of a modified cylindrical plug, an inhibitor, and the inhibitor assembled onto the modified cylindrical plug, of an embodiment of the present invention;
FIGS. 9A-C are top, side and sectional views, and isometric illustrations including partially sectional views, respectively of a cylinder lock a selector mechanism, in accordance with an embodiment of the present invention; and
FIG. 10 are isometric illustrations including partially sectional views of the cylinder plugs and the selector mechanism of FIGS. 9A-C .
DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention includes a lock apparatus that may be opened with or without a key and methods thereof.
Reference is now made to FIG. 3 , 4 , 5 A, 5 B, and, which are end and cross sectional views of cylinder lock 110 , and to FIGS. 6A-C , which are cross-sectional, representative, and cross sectional views, respectively, of cylinder lock 110 , in accordance with embodiments of the present invention. Apart from differences described below, cylinder lock 110 is generally similar to operation of cylinder lock 10 as shown in FIGS. 2A and 2B , so that elements indicated by the same reference numerals are generally identical in configuration and operation. Embodiments of the current invention disclosed hereinbelow are directed to be generally replaceable to cylinder lock 10 and/or retrofittable to cylinder lock 10 in door lock 15 shown in FIGS. 1A , 1 B, 2 A, and 2 B.
A pin displacement mechanism 136 is located in body housing 20 to displace tumbler pins 32 and driver pins 34 . Pin displacement mechanism 136 comprises one or more configurations as shown in FIGS. 3 , 4 , 5 A, 5 B, 6 A, and 6 C, to preload driver pins 34 and tumbler pins 32 towards slot 25 when no key is present, thereby advancing part of one or more of driver pins 34 into cylindrical plug 22 and locking rotation of cylindrical plug 22 . Alternatively, pin displacement mechanism 136 may be activated to displace driver pins 34 into body housing 20 , thereby aligning them so as to enable rotation of the cylindrical plug, even when no key is inserted into slot 25 .
The term “axial” and “axially”, as used hereinbelow and in the claims is meant to describe a configuration generally parallel to an axis. Additionally, the terms “open” and “closed, when used hereinbelow and in the claims in reference to a state of the cylinder lock, are meant to describe the respective states whereby plug rotation is enabled and disabled.
Pin displacement mechanism 136 may comprise a magnetic unit 138 , as shown in FIG. 3 . Magnetic unit 138 includes a series of rotatable permanent magnets (of which one is shown in the figure), corresponding to respective driver pins 34 . Dependant on the respective polarities of the individual magnets, respective magnets serve to displace respective driver pins towards and away from slot 25 . Polarities of respective magnets of magnetic unit 138 may be configured in a non-uniform configuration to obviate magnetic “picking” of cylinder lock 110 , such as when an external magnetic field is applied to the cylinder, in an attempt to open the cylinder lock. Magnetic unit 138 includes a driver (not shown in the figure) for rotating respective magnets.
Pin displacement mechanism 136 may alternatively comprise an electro-magnetic unit 146 , as shown in FIG. 4 . Driver pin displacement functionality of electro-magnetic unit 146 is generally similar to that described hereinabove for magnetic unit 138 , except that respective electro-magnets remain stationary. Polarities of respective electro-magnets of electro-magnetic unit 146 may be changed and configured in a non-uniform configuration to obviate magnetic “picking” of cylinder lock 110 , such as when an external magnetic field is applied to the cylinder, in an attempt to open the cylinder lock. Magnetic unit 138 includes connections (not shown in the figure) for operating the respective electro-magnets.
Another configuration of the pin displacement mechanism may be that of an artificial muscle unit 156 , as shown in FIGS. 5A and 5B , showing respective locked and unlocked configurations of cylinder lock 110 . Artificial muscle unit 156 may comprise one or more respective artificial muscles, which can individually displace one or more respective driver pins towards and away from slot 25 . Artificial muscle unit 156 includes connections (not shown in the figure) for operation.
Pin displacement mechanism 136 may alternatively be a mechanical linkage 160 , as shown in FIGS. 6A and 6C . In the example shown here, mechanical linkage 160 comprises: a pin driver arm 164 , which is formed with tooth-like formation of respective plungers on one transverse edge of the arm, serving to contact corresponding driver pins; a linear driving arm 166 constrained to move generally parallel to the axis of cylindrical plug 22 and shaped to bear upon pin driver arm 164 ; and a linkage driver unit 167 which effects movement of linear driving arm 166 .
Pin driver arm 164 and linear driving arm 166 are configured to enable controlled displacement of driver pins 34 , enabling locking and unlocking, as described hereinbelow. Pin driver arm 164 is constrained to move only towards or away from slot 25 , thereby displacing corresponding driver pins towards or away from slot 25 . The opposite transverse edge of pin driver arm 164 facing linear driving arm 166 has one or more diagonally formed bearing surfaces 164 a . Linear driving arm 166 has corresponding diagonal bearing surfaces 166 a along its upper transverse surface to bear upon the surfaces of pin driver 164 . Linkage driver unit 167 may comprise a linkage attached to a rotary motor, as shown in the figure. An alternative configuration for linkage driver unit 167 is a linear motor. Yet another alternative configuration for linkage driver unit 167 is an artificial muscle. Locked and unlocked configurations are shown in FIG. 6C .
Activation of pin displacement mechanism 136 as described hereinabove may be effected by direct wiring to a power and command unit outside of cylinder lock 110 . Alternatively, power for the pin displacement mechanism operation may be obtained from at least one on-board battery and activation may be through a wireless means. One example of wired and wireless activation is through a small number pad located near cylinder lock 110 .
The embodiments described hereinabove allow for opening cylinder lock 110 and rotating the cylinder plug with a matching key, in a manner similar to that of a prior art cylinder lock, if necessary. However, when no key is present in slot 25 and pin displacement mechanism 136 is commanded to open cylinder lock 110 , there must be a means with which to similarly rotate cylindrical plug 22 and thereby open the door.
Reference is now made to FIGS. 6A-C , which are cross-sectional, representative, and cross sectional views, respectively, of the cylinder lock of FIG. 3 , with a cylindrical plug rotational handle 169 , in accordance with of an embodiment of the present invention. Rotational handle 169 is mechanically attached to the exterior edge of cylindrical plug 22 . The rotational handle has a flattened wide shape and a hinge which allows rotational handle 169 to be deployed generally axially to cylinder lock 110 , thereby enabling rotation of opened cylindrical plug 22 in a manner similar to that of when a key is inserted into the cylinder lock. When not in use, rotational handle 169 is stowed substantially perpendicularly to the longitudinal axis of cylinder lock 110 , allowing access of a key to be inserted into slot 25 .
Note that the slot in cylinder lock 110 , as shown in the end views of FIGS. 3 and 4 and in FIG. 5A , extends radially from approximately the center of cylindrical plug 22 to the periphery of the cylindrical plug, presenting an opening of the slot facing body housing 20 . As noted hereinabove, driver pins 34 and tumbler pins 32 move generally perpendicular to key 12 , and likewise perpendicularly to slot 25 . When a matching key is inserted into cylinder lock 110 (thereby displacing driver pins 34 and tumbler pins 32 to allow rotation of the plug as described hereinabove), the key is then rotated, thus rotating cylindrical plug 22 . As cylindrical plug 22 is rotated, tumbler pins 32 are retained within the cylindrical plug by body housing 20 and driver pins 34 are retained in position within body housing 20 by the cylinder plug. Upon further rotation of cylinder plug, whereby slot 25 is presented to driver pins 34 , driver 34 pins continue to be retained due to the presence of the key in the slot.
When no key is present in slot 25 and pin displacement mechanism 136 is commanded to displace driver pins 34 and tumbler pins 32 to allow rotation of the plug, cylindrical plug 22 may be rotated as described hereinabove. Upon further rotation of the cylindrical plug, the opening of slot 25 may be presented to driver pins 34 . Although no key is present in the slot, driver pins 34 are nonetheless retained in position by pin displacement mechanism 136 , as described hereinabove. However, if pin displacement mechanism 136 is presently commanded to displace driver pins 34 and tumbler pins 32 to disallow rotation of the plug, driver pins 34 may be undesirably driven into the opening of slot 25 , thereby disrupting rotation of cylindrical plug 22 . Similarly, when pin displacement mechanism 136 is commanded to displace driver pins 34 and tumbler pins 32 to allow rotation of the plug (i.e., with no key present, as described above), and following partial rotation of plug 22 (without the opening of slot 25 being presented to driver pins 34 ) displacement mechanism 136 may be presently commanded to displace driver pins 34 and tumbler pins 32 to disallow rotation of the plug. In this case, because driver pins 34 are retained in position within body housing 20 by the cylinder plug, rotation of the cylinder plug will still be allowed. Depending on the relative rotational position of the cylindrical plug, further rotation of the cylinder plug in this case will result in either engaging driver pins 34 with tumbler pins 32 (thereby disallowing rotation of the cylinder plug, as desired) or in driver pins 34 being undesirably driven into the opening of slot 25 , thereby disrupting rotation of cylindrical plug 22 as noted hereinabove. A solution to the undesirable disruption of rotation is described hereinbelow.
Reference is now made to FIGS. 7A and 7B , which are schematic illustrations of a modified cylindrical plug 222 and key 12 , in accordance with an embodiment of the present invention. Note that modified cylindrical plug 222 is formed so that slot 225 does not present an opening at the periphery of the cylindrical plug, in contradistinction to the slot in cylindrical plug 22 , as shown in the end views of FIGS. 3 and 4 and in FIG. 5A , as previously noted. Modified cylindrical plug 222 may be used in embodiments described hereinabove of cylinder lock 110 , in place of cylindrical plug 22 , thereby obviating the problem of disruption of rotation previously noted. Sectional view B-B of FIG. 7B further illustrates that slot 225 does not present an opening at the periphery of the cylindrical plug. Openings 231 are also shown in modified cylindrical plug 222 , for passage of the driver pins and the pin-tumblers.
Reference is now made to FIGS. 8A-F , which are schematic illustrations of exemplary configurations of a modified cylindrical plug 222 A and 222 B—both having slot opening 26 , an inhibitor 240 and 240 A, and the respective inhibitors assembled onto the respective modified cylindrical plugs, of an embodiment of the present invention. Apart from difference described below, elements indicated by the same reference numerals of previous figures are generally identical in configuration and operation. In the configuration shown in FIGS. 8A-C cylindrical plug 222 A has been machined or otherwise formed to reduce its diameter along much of it length to leave a ridge 238 along the length of the cylindrical plug and a. lip 239 at one end of the cylindrical plug. Inhibitor 240 is typically formed from a thin, strong, metallic material and comprises openings 241 , which are formed to substantially match and align with openings 231 , and a space 242 , which is formed to substantially match and mate with ridge 238 . The thickness of the material forming inhibitor 240 is chosen so that when the inhibitor is fitted onto cylindrical plug 222 A, the periphery of the inhibitor, ridge 238 , and lip 239 are all substantially flush. As shown in the FIGS. 8B and 8C , inhibitor 240 is formed to fit snugly about the periphery of cylindrical plug 222 A and is maintained in position on the cylindrical plug by ridge 238 , and lip 239 .
Referring to the configuration shown in FIGS. 8D-F , cylindrical plug 222 B has been machined or otherwise formed to reduce its diameter along much of it length to leave a. lip 239 at one end. Inhibitor 240 A is similar to inhibitor 240 described hereinabove except that inhibitor 240 without the space, presenting a complete peripheral surface. Inhibitor 240 A is formed to fit snugly about the periphery of cylindrical plug 222 A, having openings 241 , which are formed to substantially match and align with openings 231 . Inhibitor 240 A is maintained in position on the cylindrical plug by lip 239 .
It should be noted that any configuration similar to the configurations of modified cylindrical plugs 222 A and 222 B and inhibitors 240 and 240 A, respectively, allowing effective covering of slot opening 26 , while not inhibiting movement of driver pins 34 into and out of openings 231 , and allowing substantially free rotation of the modified plug within the cylinder body serves to solve the problem of disruption of rotation described hereinabove.
As noted hereinabove, rotating tongue 35 (refer to FIGS. 2A , 3 , 5 B, and 6 C) may be rotated by either of the cylindrical plugs when the cylinder lock is unlocked. The rotation may be controlled by means of a typical clutch mechanism, as known in the art. The control of rotation is advantageous, for example, in the case of a “blind cylinder”, where the blind end of the cylinder lock is typically towards the “inside”, meaning the side of the door which is not typically locked with a key. In the case of a conventional blind cylinder, the mechanism is designed to primarily allow rotation of the rotating tongue by the cylindrical plug from the inside, meaning the rotating tongue may be engaged when the cylinder lock is turned (unlocked) from the inside, even when the other cylindrical plug (outside) of the cylinder lock may be locked. When the outside cylindrical plug of a conventional cylinder lock is opened with a key, the key serves to engage the clutch mechanism so rotation of the rotating tongue by the cylindrical plug may be accomplished from the outside. However, because cylinder lock 110 , as described above, may be opened without the use of key 12 , a different clutch mechanism is employed, as described hereinbelow.
Reference is now made to FIGS. 9A-C and to FIG. 10 , which are top, side, and detailed sectional views, and isometric illustrations including partially sectional views, respectively, of a cylindrical plug assembly 301 and a selector mechanism 305 , in accordance with an embodiment of the present invention. Apart from differences described below, cylindrical plug assembly 301 comprises, inter alia, cylindrical plug 22 and second cylindrical plug 31 , as shown in FIGS. 2-6 , so that elements indicated by the same reference numerals in FIGS. 9A-C and FIG. 10 are generally identical in configuration and operation. Selector mechanism 305 functions to alternately allow rotation of rotating tongue 35 by plug 22 or by plug 31 . Selector mechanism 305 comprises a selector plunger 306 , a key-side drive block 340 , a blind-side drive block 341 , a selector plunger face plate 355 , a coil spring 360 , key bearing plate 364 , and a leaf spring 366 . Key-side drive block 340 and blind-side drive block 341 are positioned generally concentrically to rotating tongue 35 , and they are radially constrained at the interior axial end of their respective plugs and may move in an axial direction, as indicated in FIGS. 9C and 10 . Both drive blocks have two projecting drive tabs 368 , oriented typically 180 degrees from one another, whose purpose is to engage and rotate rotating tongue 35 . Leaf spring 366 serves to bias, key-side drive block 340 and blind-side drive block 341 towards the blind side of the cylinder lock (as shown in FIGS. 9A and 9C ) so that if cylindrical plug 22 is open (i.e. the driver pins have been aligned to allow rotation of the cylindrical plug, as described in embodiments hereinabove and by using a matching key), key-side drive block 340 is normally engaged to allow rotation of the rotating tongue. If it is desired to engage and rotate rotating tongue 35 from the blind side of the cylinder lock, selector plunger 306 is depressed towards plug 31 . Selector plunger face plate 355 , which is connected to selector plunger 306 , translates blind-side drive block 341 axially towards and against key-side drive block 340 , which in turn compresses leaf spring 366 . The resultant axial translation of blind-side drive block 341 engages it to allow rotation of the rotating tongue by cylindrical plug 31 . At the same time, key-side drive block 340 is disengaged. Selector plunger 306 may activated manually, as described hereinabove, and it may be activated by electronic means, such as a motor, in which case it may also be commanded remotely, such as by a wire or wireless connection.
Selector mechanism 305 may be operated so that the selector plunger is depressed and plug 31 rotates the rotating tongue. However, if the selector plunger is released before the engaged blind-side drive block 341 is returned to its initial axial orientation, it is possible that the selector mechanism may be inadvertently held in a configuration with blind-side block 341 engaged, thereby disengaging key-side block 340 . Should it then be desirable to engage key-side block 340 , it would not be possible to do this due to the preload of the leaf spring, maintaining blind-side block 341 in its engaged position.
A solution to this problem is afforded by the structure of key-side block 340 , as shown in FIGS. 9B and 9C and 10 . Block slot 372 extends radially from the periphery of key side block 340 , positioned typically 90 degrees from the projecting drive tabs, as shown. The block slot is formed to align with slot 25 . When the key is inserted into slot 25 , in addition to serving to allow rotation of the cylindrical plug as described hereinabove, the end of the key enters the block slot and bears upon key bearing plate 364 , which is preloaded by coil spring 360 , serving to urge key-side block 340 against blind-side block 341 . Rotation of the key presently serves to rotate both key-side block 340 and blind-side block 341 . The blind-side block may thereby be disengaged by rotating the key back and forth as necessary, typically approximately 30 degrees in each direction. Following this, key side block 340 is engaged and may rotate rotating tongue as described hereinabove.
Whereas the cylindrical plug assembly shown in FIGS. 3-10 has tumbler pins 32 and driver pins 34 and a blind end, embodiments described hereinabove are likewise applicable for a cylindrical plug with tumbler and driver pin sets at both ends, mutatis mutandis. Whereas references hereinabove have been made to a cylinder lock as typically used in a door, embodiments of the current invention are likewise applicable to any configuration wherein a cylinder lock is typically applied. Such configurations may include, but are not limited to: drawers, windows, safes, gates, etc.
It will be appreciated that the above descriptions are intended only to serve as examples, and that many other embodiments are possible within the scope of the present invention as defined in the appended claims. | A cylinder lock device including: a body housing having a bore, with a direction of elongation defining an axial direction for the device; a rotatable cylindrical plug in the bore, the plug having an axially extending key slot from at least one end of the plug; a plurality of driver pins configurable substantially perpendicular to the key slot and located within the body housing and substantially outside of the plug; a plurality of tumbler pins corresponding to and positionable substantially collinear with each one of the plurality of driver pins and substantially inside the plug, the tumbler pins displaceable by a key to bias the driver pins to enable rotation of the plug, the driver pins adapted to displace the respective tumbler pins; and a displacement mechanism being deployed within the body housing and adapted to displace the plurality of driver pins thereby selectively enabling rotation of the plug when no key is present in the slot. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to suspension pivot joints. More particularly, the present invention relates to an elastomeric bushing which allows articulation through flexing of the elastomeric material but also allows pivoting or rotation through sliding of the elastomeric material.
BACKGROUND OF THE INVENTION
[0002] Automobiles and other vehicles normally incorporate suspension systems designed to absorb road shock and other vibrations. Many vehicles are provided with independent suspensions located at each wheel. These suspensions are designed to independently minimize the effect of shock loading on each of the wheels.
[0003] Suspension systems commonly employ stabilizer bars which interconnect independent suspensions on opposite wheels, lower control arms, upper control arms or strut assemblies, steering linkage and steering knuckles which are typically interconnected to each other through pivot joints such as ball joint assemblies.
[0004] Conventional ball joint assemblies comprise a ball stud seated in a socket. In a suspension link, each end of the link incorporates a socket, and a ball is seated in each socket. The stud, which extends from the ball of the ball joint assembly, is connected to one of the wheel assembly components. Ball joint assemblies allow articulation of the joined suspension components in both an angular and rotational direction through sliding of the joint components. The articulation due to sliding of the joint components offers low-torque rotation, but these designs do not offer shock isolation, since all of the components are typically made from rigid materials such as metal and/or hard plastic.
[0005] Another design for the pivot joints is an elastomeric bushing. The elastomeric bushing can be mechanically bonded, it can be chemically bonded during molding or it can be chemically bonded after molding. The elastomeric bushing allows articulation of the suspension components in both an angular and rotational direction through flexing of the elastomeric material. Elastomeric bushings offer excellent shock isolation but they have limited rotational capability because they rely on the flexing of the elastomeric material during rotation. The flexing of the elastomeric material adds a considerate amount of parasitic torque to the pivoting of the suspension and thus leads to a degraded ride performance. In addition, the parasitic torque can complicate the initial assembly of the suspension system.
[0006] The continued design for pivot joints includes the development of joint assemblies that offer the advantage of shock isolation but also provide the advantage of low-torque rotation.
SUMMARY OF THE INVENTION
[0007] The present invention provides the art with a pivot joint which offers the isolation characteristics of an elastomeric bushing as well as the free rotation (low-torque) properties of a ball joint assembly. The pivot joint of the present invention provides for high articulation for improved ride and when used as a suspension pivot it provides for free rotation which enables convenient vehicle assembly. The present invention provides these advantages in an efficient package that can also include captivation, sealing and compression rate tunability.
[0008] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limited the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
[0010] [0010]FIG. 1 is a side view of a typical MacPherson strut suspension system incorporating the unique pivot joint in accordance with the present invention;
[0011] [0011]FIG. 2 is a side view of a typical wishbone suspension system incorporating the unique pivot joint in accordance with the present invention;
[0012] [0012]FIG. 3 is a vertical cross-sectional view of the pivot joint shown in FIGS. 1 and 2;
[0013] [0013]FIG. 4 is a vertical cross-sectional view of a pivot joint incorporated into a sway bar link in accordance with another embodiment of the present invention; and
[0014] [0014]FIG. 5 is an enlarged view of the pivot joint illustrated in FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
[0016] There is shown in FIG. 1 a MacPherson strut suspension system which incorporates the unique pivot joint in accordance with the present invention and which is designated generally by the reference numeral 10 . MacPherson strut suspension system 10 comprises a steering knuckle 12 , a strut 14 having a shock absorber 16 , a lower control arm 18 and a pivot joint 20 . During suspension movements of suspension system 10 , lower control arm 18 pivots about an axis 22 and strut 14 pivots about a point 24 located along the axis of shock absorber 16 . The pivoting movement of lower control arm 18 causes pivot joint 20 to angulate or pivot with respect to a generally vertical axis to compensate for the angular differences between lower control arm 18 and steering knuckle 12 . During a steering maneuver of suspension system 10 , steering knuckle 12 rotates or pivots with respect to lower control arm 18 . The rotating or pivoting movement of steering knuckle 12 with respect to lower control arm 18 causes rotation of pivot joint 20 around the generally vertical axis to compensate for the rotating or pivoting of steering knuckle 12 . Thus, pivot joint 20 must accommodate both the angular movement with respect to the vertical axis as well as the rotational movement of steering knuckle 12 with respect to lower control arm 18 . FIG. 1 also illustrates a steering linkage 26 which incorporates a second pivot joint 20 .
[0017] [0017]FIG. 1 also illustrates pivot joint 20 being located at the two pivot points along axis 22 of lower control arm 18 . In this position, suspension movement of suspension system 10 causes rotation of lower control arm 18 and thus the rotation of pivot joints 20 . Any fore and aft impact loading, brake wading or the like to lower control arm 18 are resisted by the pivoting of pivot joints 20 . In the preferred embodiment, outer housing 54 is attached to lower control arm 18 and bolt 70 or its equivalent is secured to or is a part of a lower control rod (not shown) which extends along axis 22 between the two pivot joints 20 . Also, each pivot joint 20 can be secured to a separate portion of the vehicle by bolt 70 .
[0018] Referring now to FIG. 2, a wishbone suspension system 30 is illustrated. Wishbone suspension system 30 comprises a lower control arm 32 , an upper control arm 34 , a steering knuckle 36 , a spring assembly 38 , a shock absorber 40 , a lower pivot joint 20 and an upper pivot joint 20 . During suspension movements of suspension system 30 , lower control arm 32 pivots about an axis 42 and upper control arm 34 pivots about an axis 44 . The pivoting movement of lower control arm 32 causes lower pivot joint 20 to angulate or pivot with respect to a generally vertical axis to compensate for the angular differences between lower control arm 32 and steering knuckle 36 . In a similar manner, the pivoting movement of upper control arm 34 causes upper pivot joint 20 to angulate or pivot with respect to the generally vertical axis to compensate for the angular differences between upper control arm 34 and steering knuckle 36 . During a steering maneuver of suspension system 30 , steering knuckle 12 rotates or pivots with respect to lower control arm 32 and also rotates or pivots with respect to upper control arm 34 . The rotating or pivoting movement of steering knuckle 36 with respect to lower control arm 32 causes rotation of lower pivot joint 20 around the generally vertical axis to compensate for the rotating or pivoting of steering knuckle 36 . In a similar manner, the rotating or pivoting movement of steering knuckle 36 with respect to upper control arm 34 causes rotation of upper pivot joint 20 around the generally vertical axis to compensate for the rotating or pivoting of steering knuckle 36 . Thus, both lower pivot joint 20 and upper pivot joint 20 must accommodate both the angular movement with respect to the vehicle axis as well as the rotational movement around the vertical axis of steering knuckle 36 with respect to lower control arm 32 and upper control arm 34 , respectively. FIG. 2 also illustrates steering linkage 26 which incorporates another pivot joint 20 .
[0019] [0019]FIG. 2 also illustrates pivot joint 20 being located at the two pivot points along axis 42 of lower control arm 32 and being located at the two pivot points along axis 44 of upper control arm 34 . In these positions, suspension movement of suspension 30 causes rotation of both lower control arm 32 and upper control arm 34 and thus the rotation of pivot joints 20 . Any fore and aft impact loading, brake loading or the like to lower control arm 32 and/or upper control arm 34 are resisted by the pivoting of pivot joints 20 . In the preferred embodiment, outer housing 54 is attached to lower control arm 32 or upper control arm 34 and bolt 70 or its equivalent is secured to or is a part of a lower or upper control rod (not shown) which extends along axis 42 or 44 , respectively, between the two pivot joints 20 . Also, each pivot joint 20 can be secured to a separate portion of the vehicle by bolt 70 .
[0020] Referring now to FIG. 3, pivot joint 20 is illustrated in greater detail. Pivot joint 20 is shown in FIG. 1 as a lower pivot joint, as a steering pivot joint and as a control arm pivot joint; and in FIG. 2 as a lower and an upper pivot joint, as a steering pivot joint and as a control arm pivot joint. It is within the scope of the present invention to utilize pivot joint 20 in these applications or in other applications requiring the angulation and/or rotation of pivot joint 20 .
[0021] Pivot joint 20 comprises an inner rigid housing 50 , a Self-Lubricating Elastomer (SLE™) sleeve 52 and an outer rigid housing 54 . Inner housing 50 is a generally cylindrical housing defining an annular groove 56 . Sleeve 52 is an annular sleeve disposed around inner housing 50 and it defines an annular rib 58 disposed within groove 56 . Outer housing 54 is a generally cylindrical housing disposed around sleeve 52 and inner housing 50 .
[0022] Sleeve 52 extends below a lower surface 60 of inner housing 50 and below an outward radial flange 62 of outer housing 54 . Inner housing 50 defines a central bore 64 , sleeve 52 defines a central aperture 66 and outer housing 54 defines an aperture 68 . Bore 64 and apertures 66 and 68 accommodate a bolt 70 which secures pivot joint 20 to the appropriate suspension component. The portion of sleeve 52 which extends beyond lower surface 60 will be compressed to provide a seal for pivot joint 20 . After bolt 70 is tightened, a plastic cap 72 is fit within aperture 68 to also provide a seal for pivot joint 20 . Outer housing 54 is secured to the appropriate suspension component by being press fit within an aperture or by other means known in the art. In the preferred embodiment, bolt 70 is secured to knuckle 12 or 36 or to the appropriate control rod and outer housing 54 is secured to control arm 18 , 32 or 34 .
[0023] Inner member 50 is coated with a low friction material 80 such as, but not limited to, PTFE. Sleeve 52 is bonded, by means known in the art, to outer housing 54 . The components can be designed to be self-captivating through mechanical interlock, if desired. In addition, the components, as is shown in FIG. 3, can be designed to be self-sealing against outside contaminants. The spring rate in both the radial and the axial direction can be controlled by the design for sleeve 52 . Pivot joint 20 , shown in FIG. 3, provides captivation, sealing and radial/axial tuning.
[0024] During operation, pivot joint 20 offers shock isolation due to the elastomeric properties of sleeve 52 . Sleeve 52 is also free to rotate about inner housing 50 with minimal windup and therefore low torque. The low-torque rotation is accomplished through the sliding of sleeve 52 on low friction material 80 located on inner member 50 while the outer surface of sleeve 52 is bonded to outer housing 54 .
[0025] While FIG. 3 illustrates one design for pivot 20 , pivot 20 could utilize different shapes of inner housing 50 , sleeve 52 and outer housing 54 to adjust package size, load capacity, captivation, spring rates and sealing properties based on application requirements. In addition, coatings or greases different than coating 80 could be used to reduce friction. Finally, other materials for sleeve 52 can be used as long as proper sliding can be achieved between sleeve 52 and inner housing 50 .
[0026] Referring now to FIG. 4, a sway bar link 110 is illustrated having a pivot joint 120 in accordance with another embodiment of the present invention. Sway bar link 110 comprises a longitudinally extending link 112 , an elastomeric joint 114 and pivot joint 120 . Link 112 is a formed metal or composite member which defines a first bushing bore 116 and a second bushing bore 118 .
[0027] Elastomeric joint 114 comprises an inner tubular member 112 , an annular elastomeric member 124 and a cylindrical outer member 126 . Inner tubular member 122 extends through cylindrical outer member 126 with annular elastomeric member 14 being disposed between them. Typically, annular elastomeric member 124 is bonded to both inner tubular member 122 and cylindrical outer member 126 . Cylindrical outer member 126 is press fit or otherwise secure within first bushing bore 116 . A bolt (not shown) similar to bolt 70 described above, extend through inner tubular member 122 to secure sway bar link 110 to the vehicle and/or the vehicle's suspension system.
[0028] Referring now to FIG. 4 and 5 , pivot joint 120 comprises an inner tubular member 132 , an annular elastomeric member 134 and an outer generally cylindrical member 136 . Inner tubular member 132 defines a through bore 138 and a generally spherical or contoured outer surface 140 . Through bore 138 accommodates a bolt (not shown) similar to bolt 70 described above, to attach say bar link 110 to the vehicle and/or the vehicle's suspension system. The outer surface of inner tubular member 132 can be coated with a low friction material 80 as detailed above for inner member 50 , if desired. Annular elastomeric member 134 defines a generally spherical or contoured inner surface 142 which mates with spherical or contoured outer surface 140 of inner tubular member 132 . A generally cylindrical extension 144 extends from each end of elastomeric member 134 as shown in FIGS. 5 and 6. Inner tubular member 132 is designed to rotate and pivot within annular elastomeric member 134 . This movement is facilitated by the materials used to manufacture these components or by the addition of a lubricant such as, but not limited to, low friction material 80 . Annular elastomeric member 134 is disposed within and bonded to outer generally cylindrical member 136 . While being described as being bonded to outer member 136 , it is within the scope of the present invention to utilize the compression of annular elastomeric member 134 to create the necessary retention of annular elastomeric member 134 by outer generally cylindrical member 136 . Outer generally cylindrical member 136 is press fit or otherwise secured within second bushing bore 118 .
[0029] During operation, pivot joint 120 offers shock isolation due to the elastomeric properties of annular elastomeric member 134 . Inner tubular member is free to rotate about annular elastomeric member 134 and outer generally cylindrical member 136 about a first axis 150 with minimal wind-up and therefore low torque. The low torque rotation is accomplished through the sliding of outer surface 140 on inner surface 142 with or without lubrication and/or low friction material 80 while the outer surface of annular member 134 is secured to outer member 136 . In a similar manner, low torque pivoting is accomplished through the sliding of outer surface 140 on inner surface 142 with or without lubrication and/or low friction material 80 around a second axis 152 generally perpendicular to first axis 150 . Circular extensions 144 of annular elastomeric member 134 cushion the interface between inner tubular member 132 and outer generally cylindrical member 136 .
[0030] Pivot joint 120 can be a direct replacement for pivot joint 20 illustrated at various positions in FIGS. 1 and 2.
[0031] The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention. | A pivot joint has a low friction rotational property by allowing the elastomeric bushing to rotate with respect to the inner metal. A low friction material can be incorporated between these two components to facilitate the rotation, if desired. The elastomeric bushing helps to isolate the pivot joint and prevent the transmission of vibrations. In one embodiment, the elastomeric bushing is also allowed to pivot about an axis generally perpendicular to its axis of rotation. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a division of copending U.S. application Ser. No. 11/029,303, now U.S. Pat. No. ______, filed on Jan. 5, 2005, incorporated herein by reference in its entirety, which claims priority from, and is a 35 U.S.C. § 111(a) continuation of, co-pending PCT international application serial number PCT/US03/21496 filed on Jul. 8, 2003, designating the U.S., incorporated herein by reference in its entirety, which in turn claims priority from U.S. provisional application Ser. No. 60/394,701 filed on Jul. 8, 2002, incorporated herein by reference in its entirety. Priority is claimed to all of the above-identified patent applications.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made with Government support under Grant No. CTS-9816494, awarded by the National Science Foundation and Grant No. N00014-1-0919, awarded by the Office of Naval Research. The Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] This invention pertains generally to the generation of nano-scale patterning on suitable surfaces and particularly to force directed nanoparticles utilized in nanopatterning, by inducible reactions, the surface of self-assembled monolayers that are anchored to atomically smooth surfaces. More particularly to electrophoretically directible photocatalytic quantum dots employed in nanopatterning, by photochemical reactions, the photocatalytically active surface of self-assembled monolayers that are anchored to atomically smooth surfaces. For exemplary purposes only and not by way of limitation, the stages involved in an embodiment of the subject nanopatterning comprise preparing and characterizing atomically smooth surfaces, synthesizing azide functionalized self-assembled monolayer (SAM) and modifying the smooth surface, synthesizing CdS and/or CdSe quantum dots of various sizes, characterizing and adsorbing them onto the SAM surface, photocatalytic reduction of the azide functionalized SAM and characterizing the reduced surface (using FTIR, STM, etc.), and demonstrating electrophoretic mobility of the quantum dots on the SAM with the simultaneous photocatalytic reduction to obtain nanopatterns.
[0005] 2. Description of Related Art
[0006] Standard lithographic techniques for producing markings on surfaces will reach their useful limit for complex surface patterning at a feature size of ˜100 nm. If the predicted size, speed and power advantages of molecular electronics are to be realized completely, means must be achieved to create complex patterns with a feature size of ˜5-10 Å. At this molecular limit, logic devices with densities on the order of ˜10 12 gates/cm 2 become conceivable.
[0007] Several researcher groups are working to develop nanocircuitry based on the self-assembly of carbon nanotubes into a two-dimensional grid. Others, (see below) plan to etch surface patterns using arrays of scanning probe microscopy (i.e., AFM or STM) tips. Both of these approaches are fundamentally different than the subject invention and do not permit the simultaneous creation of a billion or more (virtually an unlimited number) copies of a complex, user-defined nanopattern at high density on a surface.
[0008] Specifically, impressive progress has been made toward realization of nanoscale, molecular electronic devices (1-3). Plausible designs have been conceived (3) and exciting experimental progress has been achieved. (4, 5) For example, Heath et al. (4) describe a molecular-based logic gate where redox-active rotaxanes serve as the switching elements. Rotaxanes are multicomponent structures consisting of a large dumbbell-shaped molecule and one or more ring-shaped molecules trapped on the dumbbell. The rotaxane used in this study showed 60- to 80-fold change in conductivity with redox state. Thus, this “molecular switch” could be opened by oxidizing the molecule resulting in dramatically reduced current flow. Although these rotaxane-based switches open irreversibly, Heath et al. envision such molecular switches as constituents of a chemically assembled electronic nanocomputer (CAEN), which will be based on chemically synthesized and assembled nano- or molecular-scale components including molecular-scale wires.
[0009] Given the finite yields of chemical reactions, a CAEN would have many defects. In an earlier publication, Heath et al. demonstrated a concept for a highly defect tolerant computer architecture that is directly relevant to CAEN design. (6) Their experimental system was a massively parallel computer built of relatively inexpensive components containing many defects. In their design, a “tutor” system locates and tags CAEN defects, which subsequently can be circumvented thereby enabling surprisingly powerful computational performance. However, an approach to assembling an actual CAEN with the necessary interconnections between molecular- or nano-scale logic gates has not been demonstrated in the laboratory.
[0010] Most proposed approaches to patterning surfaces at the molecular scale rely on AFM or STM, or self-assembly, although recently, “nanolithography at the Heisenberg limit” was reported which gave pattern resolution of ˜20 nm. (7) This process did not involve lithography in the usual sense, rather a beam of metastable argon atoms passing through an optical standing wave was de-excited with a spatial dependence that resulted in the patterning of silicon or silicon dioxide substrates in the atom-beam path. A simple pattern of lines was created with a feature size limited by the Heisenberg uncertainty principle as applied to the position and momentum spreads of the localized metastable atoms. Although impressive, it is not apparent how this technique could provide a route to generation of complex, user-defined nanopatterns.
[0011] Ten years ago, researchers demonstrated the use of STM to deposit Xe atoms in precise locations to spell “IBM” on a single-crystal Ni substrate. (8) This impressive feat led to widespread speculation that scanning probe microscopy could lead to viable approaches for the nanopatterning of surfaces. More recently, another group showed that when silver nanoparticles are nudged along a silicon surface with an STM tip they leave behind a track of silver atoms. (9) In this way, “nanowires” might be drawn on a surface. However, as with the earlier STM work, huge technical obstacles remain in the development of STM-based nanopatterning of surfaces of the kind needed for nanocomputers where a repetitive pattern must be created over a macroscopic surface area. Patterning a macroscopic surface with a single STM tip would be impracticably slow, and processes based on vast arrays of tips appear enormously complex and expensive.
[0012] Many believe that the self-assembly approach will provide a means to generate molecular-scale patterns useful for nanoelectronic device manufacture. Indeed, many examples of highly ordered surface nanopatterns have been published based on molecular self-assembly of block copolymers and surfactants, for example. (10) The science of self-assembly still is in its infancy, however, and it is not a straightforward matter to program molecules to assemble into an arbitrary, user-defined nanopattern that would give the necessary interconnections between sites for logic gates.
BRIEF SUMMARY OF THE INVENTION
[0013] An object of the present invention is to provide a method of producing a nanopattern on a suitable surface.
[0014] Another object of the present invention is to furnish a method of generating a nanopattern on a self-assembled monolayer by use of a force motivated particle which interacts with an inducing event to produce a detectable trace on the monolayer.
[0015] A further object of the present invention is to supply a method of generating a nanopattern on a surface of a self-assembled monolayer, anchored to an atomically smooth substrate, by use of a electrophoretically motivated charged quantum dot which photocatalytically interacts with irradiation light to produce a detectable trace on the surface.
[0016] Still another object of the present invention is to disclose a method of generating one or more nanopatterns on a surface of a self-assembled monolayer formed from a plurality of photocatalytically reactive compounds, anchored to an atomically smooth substrate, by use of a electrophoretically motivated charged quantum dot which photocatalytically interacts with light to produce a photocatalytically induced trace on the surface.
[0017] Yet a further object of the present invention is to describe a product having a nanopattern altered surface, wherein the nanopattern altered surface is produced on a surface of a self-assembled monolayer, anchored to an atomically smooth substrate, by use of a force motivated nanoparticle which inducible reacts with an inducing event to produce a detectable trace on the monolayer surface.
[0018] Disclosed is a novel approach for creating complex, user-defined patterns on suitable surfaces at the molecular (“nano”) scale. The subject approach to surface patterning may yield complex patterns with a feature size of ˜25 Å (˜2.5 nm), and perhaps smaller. The basic idea behind the subject nanopatterning process is to use a force field (e.g., an electric field/electrophoretic field, magnetic field, and the like) to direct the movement of path-directable nanoparticle (e.g., charged photocatalytic, semiconductor nanoparticles (e.g., CdS, CdSe, and the like quantum dots or Qdots)) around on a self-assembled monolayer (SAM) chemisorbed or otherwise anchored on an atomically smooth substrate (e.g., gold, silicon, and the like) while simultaneously exposing the surface to an inducing event that causes a chemical alteration in the surface of the monolayer (e.g., illuminating the surface (see FIG. 1 )). If the surface of the SAM is comprised of chemical functional groups that can be photocatalytically altered by the Qdots then a trail of reacted molecules will be left behind as the Qdots are directed electrophoretically about the surface of the SAM. By changing the orientation of the electric field in the plane of the substrate, complicated patterns may be drawn. Large numbers of Qdots (billions, for example) could be spread on a SAM surface to draw the same pattern simultaneously. Further, if exposure to light is the inducing event, by intermittently shielding the light source, a non-reacted or “pen-ups” portion of the trace is included in the pattern.
[0019] A virtually unlimited variety of chemically functionalized surfaces with characteristic dimension similar to that of the photocatalytically active Qdots (˜1-3 nm) could be built up from these patterned surfaces. The subject approach to surface patterning has the potential to yield complex patterns with a feature size of ˜25 Å (˜2.5 nm), and perhaps smaller. No other reported or planned technologies appear to exist to achieve such resolution in the production of user-defined, complex patterns on surfaces. Further, the subject invention involves wet chemistry and unsophisticated equipment, could be carried out in relatively inexpensive production facilities and means to pattern interconnections between the logic gates of a molecular computer. Further, the subject approach offers a route to the economical production of ultra-small, high-speed, and low-power devices that combine many functions such as sensing, image processing, computation, signal processing, and communications.
[0020] There are no published technologies available for patterning surfaces of any chemistry at the scale of a few nanometers. The subject approach entails a shift from current lithographic methods resulting in microscale patterns of inorganic materials to molecular dimension patterns, nanoscale, composed of organic chemicals. In addition to the tremendous organic synthesis knowledge base that can be drawn upon in the design of our surfaces, organic chemistry provides for straightforward interfacing with biological molecules and systems. Nanopatterned organic surfaces may enable the organization of effective molecular devices for the mimicry of biological systems such as those for vision, sensing, and complex-molecule synthesis. The subject process of nanopatterning may be employed for the templated synthesis of macromolecules of defined size, shape, and chemistry. Here, the nanopattern will serve as a guide for the assembly of monomers that subsequently may be cross-linked to form a macromolecule with a shape defined by the nanopattern. Such macromolecules could be designed to give fluids unique viscous and/or optical properties. Further, the subject invention may be able to produce, on demand, using templated synthesis, a set of pre-programmed molecular building blocks that could self-assemble to give “smart materials” for applications in molecular electronics, photoenergy transduction, or chemical catalysis.
[0021] The use of a light induced change in the surface of the monolayer to produce a detectable trace is used by way of example only and not by way of limitation and it is noted that other inducing events (chemical, electric, magnetic, and the like) are considered within the realm of this disclosure. Thus, for a photochemically related process, generally, the stages involved in the subject nanopatterning comprise several interrelated steps. An atomically smooth surface on a base substrate is prepared from a suitable material such as gold, silicon, silicon oxide, and equivalent substances. Photocatalytically active molecules, usually organic (again, it is stressed that organic molecules and inorganic molecules may be utilized to practice the subject invention), that self-assemble into a monolayer on the atomically smooth surface are obtained or synthesized and allowed to self-assemble on the selected atomically smooth surface into the photocatalytically active monolayer. Photocatalytic and charged nanoparticles/quantum dots are obtained or synthesized in various sizes, depending on their ultimate usage (e.g., width of the final detectable trace), from cadmium and either sulfur or selenium containing compounds and adsorbed onto the surface of the monolayer. The photocatalytic event on the surface of the monolayer is initiated by exposure to light, thereby producing a detectable area on the surface of the monolayer.
[0022] The photocatalytic event produced detectable area is extended in a desired trace over the monolayer's surface by the application of variable electrophoretic forces. Clearly, the desired trace may be extremely complex and programmed by standard means to transpire.
[0023] Although the proposed technology may never completely supplant microlithography, it offers an entirely new approach that also provides a route to applications that are not completely foreseeable at this time. Our approach entails a shift from inorganic to organic chemistry for the patterning of surfaces. Besides the tremendous organic synthesis knowledge base that can be drawn upon in the design of our surfaces, organic chemistry provides for straightforward interfacing with biological molecules and systems. Nano-patterned organic surfaces may enable the organization of effective molecular devices for the mimicry of biological systems such as those for photoenergy transduction, vision, sensing, and complex-molecule synthesis.
[0024] Further aspects of the invention will be brought out in the following portions of the specification, wherein the detailed description is for the purpose of fully disclosing preferred embodiments of the invention without placing limitations thereon.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0025] The invention will be more fully understood by reference to the following drawings which are for illustrative purposes only:
[0026] FIG. 1 is an illustration depicting a basic electrophoretic cell in which the subject invention is practiced.
[0027] FIG. 2 is an illustration showing a more sophisticated electrophoretic cell than seen in FIG. 1 . A photocatalytic CdS Qdot with positive surface charge moving under the direction of a variable (magnitude and direction) electric field across a lawn of reactive ligands chemisorbed on an atomically smooth substrate. An array of electrodes also could be used for computer controlled changes in electric field orientation in the plane of the surface. Those ligands in contact with the Qdot while it is illuminated will react leaving behind a trail of chemically modified species. Complex patterns with “pen-ups” and with a feature size similar to that of the Qdot (˜2.5 nm) may be drawn by controlling the magnitude and direction of the electric field and by intermittently shielding the laser light source with a controllable shutter. Many CdS Qdots may be adsorbed on a surface to draw a pattern simultaneously.
[0028] FIG. 3 is UV-spectra of the azido- and amino-aldehyde compounds.
[0029] FIG. 4A is a schematic representation of photocatalyzed azide reduction with formate as the electron donor.
[0030] FIG. 4B is a schematic representation of photocatalyzed azide reduction with methanol as the electron donor.
[0031] FIG. 5 is an AFM image of atomically smooth gold prepared as described above. Area: 25 μm 2 . Roughness (rms): =2.64 Å.
[0032] FIG. 6 is a schematic representation of polyarylimine formed by photocatalytic reduction of the surface adsorbed aromatic azidoaldehydes.
[0033] FIG. 7 is a schematic representation of a photocatalytic decarboxylation according to the subject invention.
[0034] FIG. 8 is a schematic representation of a photocatalytic reduction of a diazoketone to a carboxylic acid according to the subject invention.
[0035] FIG. 9 shows absorbance spectra for CdS and CdSe Qdots.
[0036] FIG. 10A is a first SAM anchored to gold example.
[0037] FIG. 10B is a second SAM anchored to gold example.
[0038] FIG. 11 shows the decrease in azide peak after exposure to light (photoreduction).
[0039] FIG. 12 shows a beginning surface with non-dye reactive azide groups (left) and the stained surface (right) having dye reactive amine group that are labeled with fluorescent molecules.
[0040] FIG. 13 show a fluorescence gel electrophoresis plate indicating the migration of CdSe Qdots under an electric field.
[0041] FIG. 14 shows a confocal microscopy image of CdSe Qdots adsorbed on SiO 2 deposited on an Si surface.
[0042] FIG. 15 shows surface electrophoresis of adsorbed Qdots on a SiO 2 surface by confocal microscopy.
DETAILED DESCRIPTION OF THE INVENTION
[0043] The concept behind the subject nanopatterning process is to use a force field (e.g., an electric field, magnetic field, and the like) to direct the movement of variable sized, path-directable nanoparticles (e.g., photocatalytic quantum dots, (e.g., CdS and CdSe Qdots)) around on a self-assembled monolayer (usually organic, but inorganic is also contemplated) chemisorbed (or otherwise anchored) on an atomically smooth substrate (e.g., gold or silicon and the like) while simultaneously inducing a reaction (e.g., illuminating) the surface. If the anchored organic monolayer is composed of compounds that can be photocatalytically reduced by CdS Qdots, for example and not by way of limitation, then a trail or trace of reacted molecules, detectable state, will be left behind as the Qdots are directed electrophoretically about the surface.
[0044] For understanding one generalized embodiment of the subject invention, a useful analogy can be made between a common ballpoint writing pen that makes a user-directed line on a writing surface and the subject nanopattering device or nano-pen. The writing surface for the nano-pen comprises a suitably fabricated self-assembled monolayer, SAM, that is anchored to an atomically smooth underlying substrate. The exposed surface of the SAM comprises a plurality of chemical functional groups that are photocatalytically active under specific selectable conditions. The subject invention utilizes a charged quantum dot containing cadmium and either sulfur or selenium and ionizable organic moieties as the “ballpoint” of the nano-pen. In place of a user motivating and directing the path of the ballpoint pen, electrophoretic forces are employed in the subject device to direct the charged quantum dot in any desired direction. Utilizing the contacting charged quantum dot in conjunction with the photocatalytically active chemical functional groups on the surface of the SAM, laser light is used as the “ink” in the nano-pen. When the charged quantum dot passes along the surface of the SAM and is exposed to laser light a “traced path” of reacted surface chemical functional groups results, thereby generating any desired nanopattern on the SAM's surface.
[0045] FIG. 1 illustrates one embodiment of the subject invention. An electrophoretic cell 5 is comprised of two chambers with appropriately charged electrodes 10 and 15 in each chamber to provide an electrophoretic force through a conducting solution 20 . A narrow reaction volume extends between the two chambers and is expanded in the lower portion of FIG. 1 . As is seen in the lower portion of FIG. 1 , a self-assembled monolayer of photochemically reactive moieties 25 and substrate binding tails or substrate attachment regions 27 has a photocatalytic charged nanoparticle (Qdot) 30 adsorbed to its exposed surface. A cover slip 35 rests above the reaction volume. The substrate binding tails 27 are anchored to a substrate support 40 by variable chemical and/or physical means. Activation of the photocatalytic charged nanoparticle 30 is achieved by illumination (arrowed hu) into the reaction volume, thereby producing a detectable trace along the surface on the monolayer and the electrophoretic force move the photocatalytic charged nanoparticle 30 .
[0046] FIG. 2 illustrates a more sophisticated electrophoretic cell in which two-dimensional motion by the charged nanoparticle 30 is seen. The supporting substrate 40 has the monolayer's photocatalytically active surface groups 25 anchored to it. By changing the orientation of the electric field 11 and 16 in the plane of the substrate, complicated detectable nanopatterns 45 may be drawn. It is clear that large numbers of Qdots could be spread on a surface to draw the same pattern simultaneously. Further, by intermittently shielding, via a shutter 50 , the light source, “pen-ups” can be included in the pattern. A virtually unlimited variety of chemically functionalized surfaces with characteristic dimension similar to that of the photocatalytically active Qdots (˜1-3 nm) could be built up from these patterned surfaces. The subject invention could accelerate the study of quantum structures, such as quantum mirages (11), and may eventually lead to a relatively inexpensive means to pattern interconnections between components of a molecular computer. (4, 6)
[0047] This technology is dependent on frontier science in a number of areas including nanoparticle photocatalysis, Qdot surface electrophoresis, and photoreactive self-assembled monolayers. Colloidal semiconductor particles have long been used as photo-initiators of free radical polymerizations without a clear understanding of the relationship between improved catalytic performance and reduced size, beyond recognition of the increased surface to volume ratio for smaller colloids. (12) CdS Qdots are excellent photocatalysts due to the increased energy of excited electrons in comparison to the bulk semiconductor. (13) In fact, CdS Qdots can photocatalytically reduce nitrate, whereas bulk CdS shows no nitrate photoreduction activity. Further, the expected relationship has been shown to exist between particle surface charge and photocatalytic rates. CdS Qdots surface-passivated with positively charged amine-terminated thiols are far more active for anionic nitrate reduction than carboxy-terminated particles. (13) Thus, semiconductor Qdots can be tailor made to suit a given photocatalytic application by manipulating core composition, size, and surface chemistry.
[0048] By termination of Qdots with charged functional groups (e.g., amines, carboxyls, and the like), they are made electrophoretically mobile. In fact, gel electrophoresis has been used to size fractionate CdS Qdots with surface-adsorbed polyphosphate. (14) However, no previous studies of Qdot electrophoresis on surfaces exist. There is a necessity for balancing the need for a strong interaction between the nanoparticle and the support, in order to damp Brownian motion, with the electrophoretic force required to move the Qdot about the surface. The subject system has been designed such that the primary interaction between the highly charged Qdot and the surface will be electrostatic. The energy of electrostatic interactions generally is greater than kT, and it is not anticipated that surface Brownian motion will be a problem, although the relationship between the particle-surface bonding energy and the frictional resistance to surface motion is not straightforward (15). The electrophoretic driving force on the particle equals qE, where q is the effective charge on the particle and E is the electric field. This force must be sufficient to overcome the frictional resistance due to the interaction of the particle with the substrate. Given the large charge on ˜25 Å amino-terminated nanoparticles at neutral pH and low ionic strength, ˜80+, this driving force is large at modest field strength. Further, in one embodiment of the subject invention, a surface azide is reduced to an electro-positive amine which will repel the particle as it photocatalyzes the reduction reaction along its path. Also, the ionic strength of the surrounding aqueous solution can be adjusted to control the strength of the electrostatic interaction.
[0049] Although we will use “atomically smooth” surfaces for this work, an additional impediment to particle movement will be the occasional underlying step up of one or more atomic diameters on the substrate. Since an atomic step on silicon or gold surfaces measures just a few angstroms, it is not expected that such a step will present a significant barrier to our order-of-magnitude larger, ˜25 Å-diameter particles. The rms roughnesses measured for Si/SiO 2 or gold surfaces of the type used are 1-1.5 Å or 2.5 Å (16, 17), respectively, which is consistent with the notion that the roughness largely is due to atomic steps. Further, alkyl spacers (often a plurality of methylenes) between the smooth substrate and the photocatalytically reactive group of the surface adsorbed ligands tend to smooth out defects in the underlying substrate through rotation about the C—C bonds to adjust their length. The driving force for this smoothing effect arises from a lowering of the surface energy when more of the hydrophobic spacer is shielded from contact with the aqueous solvent. Based on these arguments, it appears very likely that these Qdots move electrophoretically about a modified surface as intended.
[0050] The design of the subject substrate adsorbed organic layer produces an exposed surface of sufficient uniformity and photocatalytic activity. High quality, self-assembled monolayers (SAMs) of organic compounds have been created on both gold and silicon surfaces. (18-28) The best known of these are composed of thiols on gold and silanes on the native oxidized layer of silicon. In both cases, tightly packed, ordered SAMs have been characterized by a variety of techniques including scanning probe microscopes. SAMs on gold electrodes have proven to be effective insulators in electrolyte solutions due to the highly ordered, close-packed nature of chemisorbed alkanethiols in particular. (18) For the subject technology, the rate of Qdot movement on such layers terminated with reactive groups must be balanced with rates of reaction to ensure that continuous lines of chemically modified ligands can be drawn. The exemplary azide and other chemistries chosen were selected partially for their fast reaction rates, i.e., reaction time scales on the order of sub-picoseconds to nanoseconds. A 5 mW, 400 nm laser irradiating ˜0.07 cm 2 of surface results in ˜4500 photons/sec striking an individual ˜25 Å nanocrystal. This is sufficient to ensure that a trail of reacted surface ligands will be left behind a Qdot moving at 100 nm/s given the rapid, high-quantum-yield (>20%) chemistry to be employed. Here, the flux of photons (which is proportional to laser power) likely will limit the rate at which the nanoparticles can be moved about the surface.
[0051] The actual drawing of complicated patterns requires that the electric field be re-oriented in the plane of the substrate in a programmed manner. As indicated above, “pen-ups” in the pattern may be introduced simply by intermittent shielding from the light source. In the usual case, a large number of Qdots could be adsorbed on a substrate to draw up to ˜10 10 -10 12 /cm 2 copies of the same pattern simultaneously. State-of-the-art wet chemical methods for synthesis of CdS Qdots give size populations with a standard deviation of ˜5% about the mean. Separation by gel electrophoresis can be used to decrease the breadth of the distribution to a standard deviation of 2-3%. (14) Nevertheless, there is normally a distribution in particle surface charge and in electrophoretic mobility.
[0052] The subject invention has been demonstrated in one fashion by using aryl azide chemistry, which is chemisorbed onto atomically smooth gold substrate through a thiolate linkage. CdS Qdots terminated with tertiary amines are employed as the electrophoretically mobile photocatalysts. A 5 mW InGaN diode laser may be used, for example, and a Hg(Xe) lamps with optical filters was used as the required ˜400 nm light source. An additional demonstration of the subject invention is provided with a Si/SiO 2 substrate as the atomically smooth substrate and a variety of photocatalytically chemistries including photodecarboxylations, photodenitrogenations, and photoreductions of aromatic nitro compounds. The latter chemistry may provide a route to the drawing of conducting polymer “wires” on the surface.
[0053] Substantial information exists concerning CdS Qdots synthesis (13, 34, 35). For the subject invention a capping method for synthesis of the CdS Qdots is employed which was used in earlier photocatalytic work. (13, 26, 37)
[0054] A first experimental example of the subject invention involves the use of CdS Qdots as photocatalysts and a photoreducible azide compound. The azide synthesis is as follows (see Scheme 1): Commercially available 4-amino-2-hydroxybenzoic acid is converted to the corresponding azide via the diazonium salt. Esterification of this acid allows the selective alkylation of the phenolic oxygen with 10-tert-butyl-dimethylsilyloxy-1-methanesulfonyloxydecane. Removal of the silyl-protecting group followed by the simultaneous re-protection/activation of the isolated primary alcohol permits the reduction of the ester. The primary mesylate of the benzyl alcohol is then thiolacetylated to add the required thiol-carbon bond. The oxidation of the remaining free alcohol to the aldehyde followed by the base-catalyzed hydrolysis of the thioacetate yields the disulfide only. This sequence has been completed and the required disulfide has been characterized. The synthesis has been optimized.
[0000]
[0055] It has been shown that the water-soluble azide (without the thiolated alkane tail) (see Scheme 2), can be photocatalytically reduced by amine-terminated CdS Qdots at wavelengths greater than 400 nm where significant photolysis of the azide does not occur (see FIG. 3 ). This azide derivative is synthesized in an analogous fashion to the azido-disulfide shown previously.
[0000]
[0056] The above reduction is an important result in demonstrating the reduction to practice of the subject invention chemistry for nanopatterning using mobilized, surface-adsorbed CdS Qdots as photocatalysts. In addition to reduction of the azide in THF/water solution, it has been shown that the azide is transformed in the presence of nanoparticles, light, and methanol in aqueous solution. Here, methanol serves as sacrificial electron-donor and addition of sodium formate is not required. The quantum yields for these photoreductions range from 17-60% (see FIGS. 4A (formate) and 4 B (methanol)).
[0057] Experiments have been conducted to study the behavior of aromatic azidoaldehydes under reducing conditions. Upon treatment of the azidoaldehyde with triphenylphosphine or stannous chloride, the infrared absorbance of the azide disappears. In addition, polymeric material is formed (see Scheme 3). The ease with which amines and aldehydes react to form imines suggests that this polymeric material is likely to posses a polyaryl imine backbone, which could prove to be conducting.
[0000]
[0058] The extreme sensitivity of the polymer product with regard to hydrolysis has limited its characterization ( 1 H/ 13 C NMR, EI/CI LRMS, Electrospray MS, FAB MS). Best efforts at characterization support the formation of a tetramer (FAB MS). The degradation of imine-polymer compounds by hydrolysis is well precedented. (29)
[0059] Gold substrates have been created (16, 30). Ultra-flat, atomically-smooth, Au(111) surfaces of high quality have been prepared (i.e., with rms roughness of approximately 2.5 Å over 25 μm 2 as measured by AFM, see FIG. 5 ). The method involves depositing gold on atomically smooth mica. A piece of silicon wafer is adhered to the exposed gold using a ceramic glue, Epo-tek 377. Chemical and mechanical means are used to strip away the mica thereby yielding the desired gold surface.
[0060] Acquisition of the atomically smooth gold surfaces has allowed the characterization of the azide-thiol self-assembled monolayer (SAM). Using FTIR-external reflectance spectroscopy, the IR spectrum of the SAM has been collected and compared positively to the azide-disulfide solution IR spectrum.
[0061] In one embodiment of the subject invention, experiments with SAMs on gold were conducted (31-33). In another embodiment of the subject invention Si/SiO 2 is utilized as the supporting substrate.
[0062] Surface photocatalytic azide reduction by immobile CdS nanoparticles: CdS nanoparticles capped with dimethylaminoethanethiol are deposited in a macroscopic pattern using a micropipette on a gold substrate modified with an azido-disulfide SAM (see Scheme 1 above). Use of the dimethylamine as the Qdot capping agent ensures that the particles carry a surface charge and that these surfaces are inert to the proposed reaction chemistry. The positive surface charge of ˜80+ enable a strong electrostatic interaction of the Qdots with the polar azide surface. The interaction energy, w(r), between an ionic species and a dipole is given by
[0000]
w
(
r
)
=
-
(
ze
)
u
cos
θ
4
π
ɛ
0
ɛ
r
2
[0000] where z is the charge on the ionic species; e is the electronic charge; u is the dipole moment; θ is the angle the dipole makes with the normal to the ion; ∈ 0 is the permittivity of free space; ∈ is the dielectric constant of the solution; and r is the center-to-center distance between ion and dipole. (15) The strength of such interactions normally is much greater than kT in vacuum and normally is equal to or greater than kT in water. (15) It is believed that the aldehyde and azide groups on the surface adsorbed compound rotate to orient the molecule's dipole (calculated at 4.1 Debye by the AM1 method) in the direction of an approaching CdS Qdot carrying a net charge of 80+. Therefore assuming 0 equal to ˜0, an interaction energy in water at 298 K of ˜2.5 kT is calculated using the equation above. However in the subject case (see FIG. 2 ), the effective interaction energy between the Qdot and the surface is enlarged several fold, because many surface ligands will interact simultaneously with an adsorbed nanoparticle. The strength of this interaction may be gauged experimentally by rinsing the surface after adsorption of the Qdots with water of increasing ionic strength and assaying the rinse water for Qdot fluorescence. Previous work with CdS nanoparticles has shown them to fluoresce with high quantum yield. (34, 35) Retention of the particles in the original pattern on the substrate after rinsing also will be determined using epifluorescence microscopy.
[0063] The selected surface is irradiated with 400-nm light (5 mW InGaN laser, Coherent Laser Group). The surface is examined (using AFM and FTIR) for azide reduction or, specifically, imine-formation in the immediate vicinity of adsorbed particles. (Although the imine likely would be hydrolyzed, or may not even form, under aqueous solution, it may be generated upon dehydration of the surface after photocatalytic reduction of the azide.) Aqueous-phase derivatization of amines on the surface with a fluorophore (e.g., fluorescein isothiocyanate) identify the extent of photocatalytic azide reduction. A control is run in the absence of surface adsorbed CdS nanoparticles. This work demonstrates that the photocatalytic chemistry carried out in solution also occurs with surface-bound ligands and adsorbed CdS Qdots.
[0064] Imaging of electrophoretically mobile CdS nanoparticles: Particles are adsorbed onto the aryl azide-terminated surface and imaged before and after the imposition of an electric field. CdS Qdots are deposited at a given location on a modified gold surface in a low ionic strength solution (˜1 mM) and covered with a microscope slide coverslip. Qdot movement across the surface in the presence and in the absence of an electric field is monitored by epifluorescence microscopy. At the target particle velocity of ˜100 nm/s in an electric field, particle movement is resolvable in minutes.
[0065] The electrophoresis cell is machined from Teflon™ following a design used by Groves et al. to study the electrophoresis of proteins in supported lipid bilayers (see FIG. 1 ). (38) For particles of this size and with an estimated surface charge of 80+, the field strength necessary for a velocity, ν, of ˜100 nm/s in solution is ˜1 mV/cm based on the following equation which results from a balance of the electrophoretic driving force with the drag force,
[0000]
-
v
=
D
(
zF
RT
)
φ
z
.
[0000] D is the diffusivity (which can be estimated askT/3πμd); z is the charge on the nanoparticle, F is Faraday's constant; dφ/dz is the electrical field; k is Boltzmann's constant, T is temperature, μ is the viscosity; and d is the particle diameter. The electrical field strength calculated using this equation is considered a minimum, as it does not take into account the substantial friction between the Qdot and the modified gold surface in the surface adsorbed case. Nevertheless, even at field strengths 3-4 orders of magnitude greater, energy dissipation is likely <10 μW which does not result in significant Joule heating. (38) This work demonstrates that the amine-terminated particles can be driven about the azide-terminated surface by an electric field, and provides information on the relationship between field strength and particle surface velocity (although the velocity could be impacted by the surface reaction) and on the relative importance of Brownian motion from random Qdot movement over a comparable time frame at zero field strength.
[0066] Surface photocatalytic azide reduction by electrophoretically mobile CdS nanoparticles: The 400-nm laser is used to illuminate moving particles to create trails of reacted azide on the surface. A simple re-orientation of the electric field can be attempted to re-direct the moving particles at a 90° angle, for example, to the initial trajectory; and the light source is shielded at controlled intervals to create “pen-ups” in the nanopattern. The reacted molecules are imaged using AFM in both topographical and frictional force modes. In the region of the CdS particle on the surface, reduction to the amine takes place. The amine could be derivatized with a more bulky group (e.g., the bulky green fluorophore, fluorescein isothiocyanate also could serve this purpose) for better imaging. Alternatively, if the surface is dehydrated, amines and aldehydes on neighboring molecules may react readily due to their proximity giving chains of surface-bound, electrically conducting polyarylimine “wires” (see FIG. 6 for polyarylimine formed by photocatalytic reduction of the surface adsorbed aromatic azidoaldehydes). In any case, the reduced portion of the surface, with or without derivatization or polymerization, is expected to show topographical and tactile (using AFM) properties distinct from those of the unreduced layer.
[0067] The continuity of the “lines” of reacted ligand as a function of field strength provides data concerning the maximum velocity of the particles for complete surface reaction. Also, the straightness of the trails provides some measure of the influence of Brownian motion and of the need to increase the friction between the particle and the surface. Surface friction may be adjusted through the surface chemistries of the particle and substrate, through solution conditions such as ionic strength, or through temperature, for example.
[0068] It should be recognized that there are a virtually unlimited variety of chemical systems suitable for application via the subject invention. Many other smooth substrates (other than gold and silicon containing materials) are available as are a broad variety of catalytic particles (the process need not limited to photocatalysis) and reactive organic ligands. In addition, one could imagine force fields other than electrical to move appropriate particles (e.g., magnetic and the like). Techniques with silicon (see immediately below) have been developed to produce very smooth surfaces of large area for microelectronics applications. (17)
[0069] Self-Assembled Monolayers on Silicon: High-quality, self-assembled monolayers have been prepared recently on silicon surfaces by hydrosylation of terminal alkenes, by reaction of alkyl lithium and Grignard reagents with chlorine terminated surfaces, and by silylation of OH-terminated silicon (see Schemes 4A and 4B below).
[0000]
[0000]
[0070] Hydrosylation reactions rely on the thermal (20-23) or photochemical (24, 25) addition of hydrogen terminated surfaces into the double bond of terminal alkenes. The reaction is thought to occur by a radical chain mechanism and produces monolayers with Si—C linkages. Creation of surface Si—C linkages using alkyllithium and Grignard reagents requires prior preparation of a halogen-terminated surface by reaction of H-surfaces with PCl 5 in benzene. (26) Alternatively, the silylation approach relies on the reaction of, for example, alkylchlorosilanes with surface SiOH groups. (26, 28)
[0071] Experimental steps similar to those indicated will be followed with the new substrate chemistries beginning with an analysis of the photocatalytic reaction in solution followed by the work with the Qdots on the modified substrate surface.
[0072] Photocatalytically Reactive SAMs on Silicon: From a relatively large number of photocatalyzed processes that can be used to pattern a self-assembled monolayer three relatively simple systems are studied. Si—C and Si—O—SiR functionalized surfaces will have fundamentally different properties when exposed to irradiated Qdots.
[0073] Photosensitized reactions of varying types will change the properties of the exposed surface. These include the photodecarboxylation of carboxylic acids, the photodenitrogenation and Wolff rearrangement of diazoketones, and the photoreduction of aromatic nitrocompounds. Most of these processes can be readily investigated with commercially or readily available compounds to prepare the derivatized monolayers.
[0074] Photodecarboxylation Reactions: The photosensitized decarboxylation of organic acids (39, 40) is a well-known photosensitized reaction that proceeds in good chemical yields. An electron must be transferred from the catalyst surface to the carboxy group to produce a radical anion. Radical anions from neutral acids and their salts can rapidly decarboxylate to give an alkyl radical in the chain along with a molecule of CO 2 , and a hydrogen atom in the case of the neutral acid. The decarboxylation will occur in the proximity of the electrophoretically mobile CdS Qdots leaving a hydrophobic nano-trail of chemically robust hydrocarbon chains on an otherwise hydrophilic and readily derivatizable acid surface (see FIG. 7 ). Monolayers will be prepared by the methods outlined above on Si—C and Si—O—SiR surfaces with several readily accessible carboxylic acid derivatives.
[0075] Since the rates and efficiencies of decarboxylation can be affected by substituents attached to the carbon next to the carboxylic acid group α-substituents), (41, 42) a series of long chain ω-unsaturated acids and esters will be made (see Scheme 5) with and without radical stabilizing substituents in the α-position. Surfaces are prepared by alkene hydrosylation and by functionalization of surface silanols with ω-chlorosilanes.
[0000]
[0076] Photodenitrogenation and Wolff Rearrangement of Diazoketones: The photodenitrogenation and Wolff rearrangement of α-diazoketones is arguably the most important organic chemical reaction of the 20th century. (43-45) The Wolff rearrangement (see Scheme 6) is the critical chemical process behind the transformation of diazonaphthoquinone into indanecarboxylic acid within Novolak matrices. A change in solubility in the polymer matrix upon changing from the neutral diazoquinone to the carboxylic, caused by irradiation of the former through a mask, constitutes the most used microlithographic system in the world and the chemistry behind the information age revolution.
[0000]
[0077] Photosensitized and directly irradiated diazo ketones have a remarkable ability to lose molecular nitrogen and generate highly reactive ketocarbene intermediates. Within fractions of a nanosecond, the ketocarbene can undergo a Wolff rearrangement to generate a ketene (see Scheme 7). The ketene thus formed can rapidly trap water to form a carboxylic acid.
[0000]
[0078] Given the sensitivity of diazoketones to high temperature conditions, organic substrates needed for the preparation of diazoketone-terminated, self-assembled-monolayers will require the use of mild silylation procedures. The silylation of OH terminated surfaces will require the preparation of ω-chloro-, ω-dichloro- and ω-trichlorosylane-diazoketone chains (see Scheme 8 for exemplary precursor synthesis and FIG. 8 ).
[0000]
[0079] Condensation of Aromatic Diamines by Photocatalyzed Reduction of Diazides and Dinitro Compounds: The formation of surface patterns based on conducting organic polymers is highly desirable for the construction of nanoscale circuitry. Based on the organic chemistry and photocatalytic systems developed, the preparation of polymers based on the condensation of amines and aldehydes to yield polyimines is greatly advantageous. While there was some preliminary success in the catalyzed condensation of para-amino aldehydes, it has also been noted that they do not undergo a very efficient polymerization in solution without significant thermal activation or the use of relatively strong catalysts. The relative stability of the 4-aminoaldehydes towards self-coupling and condensation reactions results from their electronic structure and is not totally unexpected: while the para-amino group renders the aldehyde less electrophilic, the aldehyde group reduces the nucleophilicity of the amine. Nevertheless, the close proximity of photocatalytically reduced azides and aldehyde groups of neighboring molecules on the surface should result in ready polymerization upon dehydration of the surface.
[0080] An additional, relatively simple experiment to test the likelihood of forming a conducting polymer from the developed CdS nanoparticle technology is shown below. In order to establish the feasibility of preparing surface-imprinted polyimine-based conducting polymers, the cross-condensation reactions between 1,4-diamines with terephthalaldeydes is investigated. The main appeal of this reaction lies in the simplicity of the starting materials and on the high reactivity of diamines and dialdehydes. The preparation of cross-linked single crystals of amine residue-containing enzymes by diffusion of dialdehydes in aqueous media and at room temperature is an impressive demonstration of the potential of this reaction. (46) The diamine modified surfaces can be prepared by the photocatalyzed reduction of 1,4-diazides, as described above, and from the well known photoreduction of nitrocompounds under the subject photocatalytic conditions. A variety of substrates are commercially available and several closely related examples of amines and aldehydes have been shown to participate in the formation of aromatic azomethine polymers. (29) The physical properties of the polymer resulting from test substrates will be tested to verify if they are similar to those derived from the polymers isolated from subject synthesized monomers. The desired polymerization is achieved in the bulk by mixing the constituents under various conditions including the use of anhydrous and aqueous solvents, and in the presence of a dehydrating agents or dilute acid. The resulting products are characterized by standard methods to examine their conductive properties.
[0081] Diazides and dinitro compounds can be photo-reduced in solution with the aid of CdS (or CdSe) nanoparticles (see Scheme 9), upon which the di-aldehyde substrate can be added to initiate polymerization. This will help us understand the polymerization on the surface and will help us fine-tune the conditions that will optimize it.
[0000]
[0082] Nanopattern Drawing: In order for complex patterns to be drawn, the electric field direction (and strength, perhaps) must be re-oriented in a pre-programmed way so as to direct the photocatalytic Qdots, which serve as the “pens”, about the surface. “Pen-ups” can be introduced into the pattern by intermittently shielding the light source with a programmed shutter (see FIG. 2 ). Re-orientation of the electric field can be accomplished either by rotating the surface in a constant plane (see FIG. 2 ), by moving the electrodes about in the surface plane, or by transient charging of pairs of electrodes in an array surrounding the substrate. The latter approach likely will prove most elegant and practical because it will not entail moving parts and will not generate fluid flow as the rapid movement of the substrate or of a single pair of electrodes would. If the field strength is kept constant, then the particle motion should remain constant and programming the drawing of a pattern composed of line segments becomes a rather straightforward problem of reorienting the field vector for the prescribed lengths of time necessary to produce line segments of desired length and orientation. The drawing of curves requires that the field direction be varied constantly. This problem becomes more tractable when viewed as the drawing of arcs of known radius. The field orientation then is varied over the corresponding angle for the time necessary to draw the arc of the desired length given the constant motion of the Qdots. The reproducibility of patterns drawn simultaneously by many particles on a surface will be determined by comparing AFM images of the patterns generated by individual Qdots. It is expected that there will be some heterogeneity due to surface defects and to the small spread in particle size (˜5% standard deviation about the mean).
EXPERIMENTAL RESULTS
[0083] Preparation of quantum dots, Qdots: CdS or CdSe Qdots are prepared in standard ways. For example, amine-thiol capped CdS Qdots were prepared by mixing CdCl 2 (0.15 mM), HSCH 2 CH 2 NH 3 + Cl − (4.9 mM), and Na 2 S (0.76 mM). A similar process was utilized for CdSe Qdots. Absorption/emission spectra for CdS Qdots (16 Å) and for CdSe Qdots (19 Å) have been obtained and are shown in FIG. 9 . The amine-thiol capped Qdots were in the size range of 15-25 Å.
[0084] Photocatalytic reduction of various aromatic azides to amines have been carried out by CdS Qdots using a suitable electron donor (see FIGS. 4A and 4B and related information above). The azides studied include the following:
[0000]
[0085] The exemplary synthesis of a SAM precursor using an aromatic azide was conducted according to the pathway shown below:
[0000]
[0086] Exemplary SAMs were produced by depositing a 500 Å gold layer on a Si wafer with 50 Å of a Cr adhesive layer and then immersed for 24 hours in a freshly prepared benzene solution of 0.5 mM SAM precursor. Two SAMs produced in this manner are shown in FIGS. 10A and 10B . Both of these SAMS have been shown to be reduced to amines by either amine-thiol capped (positively charged) CdS Qdots or amine-thiol capped (positively charged) CdSe Qdots when exposed to light, usually light that is of a wavelength equal to or greater than 400 nm. FIG. 11 shows the decrease in azide peak after exposure to light (photoreduction).
[0087] An exemplary method for spotting the pattern on the surface of a SAM was achieved by staining the photoreduced amine groups with an appropriate fluorescence detectable dye, FITC (see immediately below and FIG. 12 ), but it is stressed that other detection methods for induced chemical reactions is also contemplated.
[0000]
[0088] FIG. 13 provides evidence that Qdots, in this case amine-thiol capped CdSe Qdots, do migrate under an electrophoretic charge. Standard gel electrophoresis was conducted with CdSe Qdots at pH=5.0 and an electric field of 3 V/cm. A mobility of 4.6×10 4 μm 2 /Vs was noted with fluorescence imaging of the migrated Qdots ( FIG. 13 depicts Qdots with increasing concentration from left to right).
[0089] As seen in FIG. 14 , Qdots (specifically CdSe Qdots) do adsorb to an SiO 2 deposited (LPCVD) Si surface. The confocal microscopy image shows the distributed presence of Qdots adsorbed over the SiO 2 .
[0090] The migration of Qdots over a smooth SiO 2 surface has been shown by surface electrophoresis (visualized with confocal microscopy). FIG. 15 shows an AFM image of a 5×5 μm SiO 2 surface over which Qdots have migrated in an electric field with pH=6.0, electric filed=6 V/cm, a mobility=1.0×10 3 μm 2 /Vs and utilizing copper electrodes (for FIG. 15 : Surface=SiO 2 , distance=1.22 μm, RMS=82.6 Å, and Average=65.0 Å). The lesser mobility of adsorbed Qdots on the SiO 2 surface is attributed to surface effects arising from surface roughness.
[0091] Again, in proof of the reduction to practice for the subject invention it is stressed that many experimental results, as stated above, have been achieved, including, but not limited to: 1) the photocatalytic reduction of an aryl azide-terminated self-assembled monolayer (SAM) on gold by adsorbed CdS or CdSe Qdots was shown to occur; 2) alternate aryl azide chemistries have been investigated and photocatalytic reduction by CdS or CdSe Qdots have been confirmed; 3) fluorescence tagging of aryl amines generated by photoreduction of the corresponding azides has been demonstrated; 4) atomically smooth SAMs were formed on evaporated gold films and characterized by AFM; 5) CdS and CdSe Qdots were adsorbed on a SAM and imaged by epifluorescence microscopy; 6) an electrochemical cell for electrophoretic movement of Qdots on SAMs with simultaneous monitoring by confocal epifluorescence microscopy has been constructed and tested; and 7) controlled electrophoretic movement of CdSe Qdots on Si/SiO 2 surfaces has been achieved and observed using confocal epifluorescence microscopy.
REFERENCES
[0092] Each document cited below is incorporated herein by reference into the subject specification.
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R., Highly Stable Si—C Linked Functionalized Monolayers on the Silicon (100) Surfaces Langmuir 1998, 14, 1759-1678. 22. Sieval, A. B.; Vleeming, V.; Zuilhof, H.; Sudholter, E. J. R., An Improved Method for the Preparation of Organic Monolayers of 1-Alkenes on Hydrogen-Terminated Silicon Surfaces Langmuir 1999, 15, 8288-8291. 23. Linford, M. R.; Chidsey, C. E. D., Alkyl Monolayers Covalently Bound to Silicon Surfaces J. Am. Chem. Soc. 1993, 115, 12631-12632. 24. Boukherroub, R.; Wayner, D. D. M., Controlled Functionalization and Multistep Chemical Manipulation of Covalently Modified Si(111) Surfaces J. Am. Chem. Soc. 1999, 121, 11513-11515. 25. Boukherroub, R.; Morin, S.; Benzebaa, F.; Wayner, D. D. M., New Synthetic Routes to Alkyl Monolayers on the Si(111) Surface Langmuir 1999, 15, 3831-3835. 26. Bansal, A.; Li, X.; Lauermann, I.; Lewis, N. S.; Yi, S.; Weinberg, W. H., Alkylation of Si Surfaces Using a Two-Step Halogenation/Grignard Route J. Am. Chem. Soc. 1996, 118, 7225-7226. 27. Kluth, G. J.; Sung, M. M.; Maboudian, R., Thermal Behavior of Alkylsiloxane Self-Assembled Monolayers on the Oxidized Si(000) Surface Langmuir 1997, 13, 3775-3780. 28. Fadeev, A. Y.; McCarthy, T. J., Trialkylsilane Monolayers Covalently Attached to Silicon Surfaces: Wettability Studies Indicating that Molecular Topography Contributes to Contact Angle Histeresis. Langmuir 1999, 15, 3759-3766. 29. Morgan, P. W.; Kwolek, S. L.; Pletcher, T. C. Aromatic Azomethine Polymers and Fibers. Macromolecules 1987, 20, 729-739. 30. Wagner, P.; Hegner, M.; Guntherodt, H. J.; Semenza, G. Formation and in situ modification of monolayers chemisorbed on ultraflat template-stripped gold surfaces. Langmuir 1995, 11, 3867-3875. 31. Kinnear, K. T.; Monbouquette, H. G. Direct Electron Transfer to Escherichia coli Fumarate Reductase in Self-Assembled Alkanethiol Monolayers on Gold Electrodes. Langmuir 1993, 9, 2255-2257. 32. Kinnear, K. T.; Monbouquette, H. G. 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Size Control of Ultrasmall CdS Particles in Aqueous Solution by Using Various Thiols. J. Colloid Interface Sci. 1993, 155, 23-29. 38. Groves, J. T.; Wülfing, C.; Boxer, S. G. Electrical Manipulation of Glycan-Phosphatidyl Inositol-Tethered Proteins in Planar Supported Bilayers. Biophys. J., 1996, 71, 2716-2723. 39. Bard, A. J.; Kraeutler, B. Photocatalytic Decarboxylation of Saturated Carboxylic Acids. U.S. Pat. No. 4,303,486 A 19811201 1981. 40. Wan, P.; Budac, D. In Photodecarboxylation of Acids and Lactones ; W. M. Horspool and P.-S. Song, Ed.; CRC Press: Boca Raton, 1995; pp 384-392. 41. Wan, P.; Budac, D. In CRC Handbook of Organic Photochemistry and Photobiology ; W. M. Horspool and P.-S. Song, Ed.; CRC Press: Boca Raton, 1995; pp 384-392. 42. Budac, D.; Wan, P. Photodecarboxylation-mechanism and synthetic utility. J. Photochem. Photobiol., A 1992, 67, 135-166. 43. 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[0139] Although the description above contains many details, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Therefore, it will be appreciated that the scope of the present invention fully encompasses other embodiments which may become obvious to those skilled in the art, and that the scope of the present invention is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” All structural, chemical, and functional equivalents to the elements of the above-described preferred embodiment that are known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the present claims. Moreover, it is not necessary for a device or method to address each and every problem sought to be solved by the present invention, for it to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112, sixth paragraph, unless the element is expressly recited using the phrase “means for.” | A method for producing, and a product having, a surface nanopattern, wherein the method comprises the steps of: obtaining a substrate with a smooth surface; acquiring a self-assembling monolayer precursor, wherein the precursor includes an inducible, usually photocatalytically, active region and a substrate attachment region; mixing a plurality of the self-assembling monolayer precursors with the substrate to produce a self-assembled monolayer having an exposed surface comprising the inducible active regions and anchored to the substrate smooth surface by the substrate attachment regions; obtaining a path-directable nanoparticle; contacting the path-directable nanoparticle with the exposed surface at an interface area; exposing the exposed surface contacted with the path-directable nanoparticle to an inducing event, usually exposure to light, thereby chemically altering the inducible active regions and producing a detectable state in the interface area on the exposed surface; and applying a force of variable magnitude and direction in the plane of the surface to the contacted path-directable nanoparticle to produce movement of the contacted nanoparticle over the exposed surface thereby extending the detectable state interface area into a detectable trace over the exposed surface to produce the nanopatterened surface. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of priority from German Patent Application No. 10 2011 111 725.7, filed Aug. 26, 2011, herein fully incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to textile machines with a plurality of workstations and, more particularly, to textile machines with a large number of workstations each equipped with at least one yarn processing device.
BACKGROUND OF THE INVENTION
[0003] In textile machinery manufacturing, textile machines having a large number of identical workstations have been known for a long time in various embodiments and described in relative detail in numerous patent specifications.
[0004] Textile machines of this type, frequently also known, as multiple station textile machines are, for example, rotor spinning machines, texturing machines, flyers, ring spinning machines, two-for-one twisting machines or cabling machines, etc. Multiple station textile machines of this type often have at least one generally continuous drive shaft running in the longitudinal direction of the textile machine, to which yarn processing devices, which are, for example, overhung, are connected.
[0005] Two-for-one twisting or cabling machines, for example, have a large number of identically configured workstations of this type, which are arranged next to one another on both sides of the machine longitudinal axis and are, in each case, inter alia equipped with a winding mechanism to produce a cross-wound bobbin. The winding mechanism, in this case, generally has a friction roller for the frictional drive of a cross-wound bobbin and a yarn processing device connected upstream of the friction roller in the yarn course in the form of a so-called overfeed roller, by means of which the yarn tension of the yarn running onto the cross-wound bobbin is adjusted, in other words is generally reduced.
[0006] The order of magnitude of the reduction of the yarn tension is determined here by the wrap angle of the yarn around the overfeed roller and by the peripheral speed of the overfeed roller in relation to the winding speed of the cross-wound bobbin. In practice, this means that the cross-wound bobbin driven by the friction roller rotates at a significantly lower peripheral speed than the overfeed roller.
[0007] With regard to the drive of the friction rollers and the overfeed rollers, various embodiments are prior art in conjunction with two-for-one twisting machines or cabling machines of this type.
[0008] Two-for-one twisting or cabling machines, in which both the friction rollers and the overfeed rollers of a textile machine side are in each case driven by separate drive shafts along the length of the machine, are known, for example, from German Patent Publications DE 34 03 144 A1, DE 42 17 360 C2 or DE 100 45 909 A1. With these known two-for-one twisting or cabling machines, in particular the drive shafts for the overfeed rollers along the length of the machine and located in the working region of the operator have proven not to be very advantageous both from a safety and from an operating point of view. In other words, drive shafts of this type along the length of the machine are generally, as shown in German Patent Publication DE 100 45 909 A1, for example, provided with a casing or a covering to prevent accidents, the casing only being equipped with narrow slots at the workstations. However, with drive shafts of this type along the length of the machine, in the event of an interruption of the yarn travel, for example caused by the tearing of the yarn while being wound onto the bobbin, the problem often occurs that the yarn is picked up by the drive shaft, which continues to rotate, and is wound thereon. The operator then often tends to uncover the drive shaft or the overfeed roller by removing the covering in order to thus improve the accessibility to the wound lap produced.
[0009] A procedure of this type is, however, extremely dangerous as the drive shaft continues to revolve with an unreduced speed.
[0010] The drawback in drive shafts of this type along the length of the machine is also the poor exchangeability of yarn-transporting components. The changing of an overfeed roller is, for example, relatively complex. It has therefore already been proposed in the past to dispense with drive rollers along the length of the machine, at least for the overfeed rollers, and instead to also drive the overfeed rollers by means of the drive shafts present in any case for the friction rollers.
[0011] German Patent Publication DE 10 2005 050 074 A1 describes a two-for-one twisting or cabling machine, in which the overfeed rollers of the numerous workstations are in each case mounted individually on special support elements, which make it possible to pivot the overfeed rollers between an operating position and a service position. The overfeed rollers are also in each case connected by a continuous traction means to one of the two friction shafts along the length of the machine, the continuous traction means, on the one hand, comprising a drive element arranged on one of the friction shafts along the length of the machine and, on the other hand, being drawn onto an output means non-rotatably connected to the overfeed roller. In practice, the arrangement, known per se, of continuous traction means, has proven not to be particularly advantageous, however. In other words, in these two-for-one twisting or cabling machines, an exchange of the continuous traction means “caught” by a friction shaft along the length of the machine and generally configured as a round belt is always, when necessary, relatively difficult and time-consuming, which, as at least one machine side of the two-for-one twisting or cabling machine generally has to be shut down during the change process, has a negative effect on the efficiency of the textile machine.
[0012] Two-for-one twisting and cabling machines are also known from German Patent Publication DE 10 2006 061 289 A1, in which the overfeed rollers are in each case connected by a magnetic gearing to a drive shaft, preferably to the friction shaft of one of the two textile machines. Magnetic gearings of this type are relatively insensitive to soiling and have the advantage of great operating reliability.
[0013] In contrast to positive torque transmission devices, for example, the exceeding of a limit torque upon the occurrence of an unforeseen operating condition immediately leads to the standstill of the associated overfeed roller in magnetic gearings of this type.
[0014] A serious drawback of this magnetic gearing, which is advantageous per se, is, however, its relatively complex construction, which leads to magnetic gearing of this type, in particular in relation to the above-described continuous traction means, being very expensive.
SUMMARY OF THE INVENTION
[0015] Proceeding from the aforementioned prior art, the invention is based on the object of developing a multiple station textile machine, which does not have the above-described drawbacks, but nevertheless has a reliable and economical drive for its numerous yarn processing devices, which are arranged in each case in the region of the workstations.
[0016] This object is achieved according to the invention by a textile machine with a plurality of workstations each equipped with at least one yarn processing device, and at least one drive shaft extending in the longitudinal direction of the textile machine over a plurality of workstations, each yarn processing device being connected to the drive shaft by a continuous traction means, and the drive shaft including a large number of drive devices each guiding and entraining a respective continuous traction means. According to the present invention each drive device of the drive shaft has two deflection and guide grooves arranged coaxially with respect to the drive shaft, one of the deflection and guide grooves being a component of a wheel freely rotatably mounted about the drive shaft. An output means is connected to each respective yarn processing device, each output means having front and rear guide grooves, the front guide groove being positioned at a freely accessible end of the output means and the rear guide groove being positioned in the region of the respectively associated yarn processing device. Each continuous traction means ( 19 ) has opposite end loops joined endlessly by two connecting strands. One end loop is engaged in the rear guide groove ( 26 B) of the output means ( 22 ) which is connected to the respective yarn processing device ( 41 ). The two strands extend from the one end loop and are respectively engaged in the deflection and guide grooves ( 30 , 34 ) of the drive shaft ( 35 ). Between the drive shaft ( 35 ) and the other end loop, the two strands are twisted lengthwise relative to one another by a 180 degree rotation thereof, and the other end loop is engaged in the front guide groove ( 26 A) of the output means ( 22 ). In this manner, the end loops travel in the same direction as one another in the grooves ( 26 A, 26 B).
[0017] Various advantageous embodiments of the invention are contemplated.
[0018] The configuration according to the invention has the advantage, in particular, that the continuous traction means can easily be exchanged without problems if necessary. In other words, the drive devices of the drive shaft in each case have two coaxially arranged deflection and guide grooves, one of the deflection and guide grooves being a component of a freely rotatably mounted loose wheel. When drawing up the continuous traction means, the latter can firstly be inserted by means of a loop into the rear guide groove of an output means connected to an overhung yarn processing device and then drawn around the associated drive device fixed to the drive shaft in such a way that two strands of the continuous traction means located next to one another encompass the two deflection and guide grooves of the drive device arranged coaxially with respect to the drive shaft. The remaining loop of the continuous traction means can then be inserted with a rotation through 180 degrees into the guide groove positioned at the freely accessible end of the drive means of the yarn processing device.
[0019] It is also provided in an advantageous embodiment that the deflection and guide grooves of the drive device, in which the two strands of the continuous traction means are guided, are arranged adjacently and in parallel. The milling and bending forces acting on the continuous traction means during operation can be minimized by an arrangement of this type of the deflection and guide grooves, which has a very positive effect on the service life of the respective continuous traction means.
[0020] According to another aspect of the invention, it is furthermore provided that drive device preferably has a rotation body, which is non-rotatably arranged with respect to the drive shaft, with a deflection and guide groove for the strand of the continuous traction means to be driven and a rotation body, which is rotatably mounted with respect to the drive shaft, with a deflection and guide groove for the strand of the continuous traction means running counter to the drive direction. In other words, the deflection and guide grooves are arranged and configured in the rotation body of the drive device in such a way that proper running of the continuous traction means is always ensured.
[0021] It is provided in an advantageous embodiment that the drive device is configured as a belt pulley element, with a base body non-rotatably fixed to the drive shaft and a loose wheel freely rotatably mounted on the base body. In this case, the base body is equipped with a deflection and guide groove for the strand of the continuous traction means to be driven, while the loose wheel has a deflection and guide groove for the strand of the continuous traction means running in the opposite direction. A configuration of this type of the drive device does not only ensure reliable driving of the yarn processing devices arranged in the region of the workstations of the textile machine, but overall a long service life of the drive device.
[0022] According to another feature of the invention, it is provided in an advantageous embodiment, that one drive shaft is arranged for each machine side of the textile machine and is equipped with a large number of friction rollers driving the take-up bobbins, the drive devices being formed by deflection and guide grooves integrated into the friction rollers for the strand of the continuous traction means to be driven and adjacently arranged belt pulley devices. In other words, the belt pulley devices in each case have a loose wheel with a deflection and guide groove for the strand of the continuous traction means running in the opposite direction. A design of this type does not only allow a very compact configuration of a workstation, so that it is easily ensured that the spindle spacing of the textile machine can be minimized, but it also keeps the structural outlay for the drive devices within limits.
[0023] It is also provided in an advantageous embodiment that the loose wheel is freely rotatably connected to the base body by a bearing.
[0024] A roller bearing is the optimal solution for the provided purpose of use, as roller bearings of this type are not only proven, economical mass production components, which also manage higher rotational speeds without problems, but roller bearings of this type are also components, which are distinguished by a long service life.
[0025] In an alternative embodiment, a sliding bearing may also be used, however, as a bearing. Sliding bearings of this type are also proven, low-maintenance machine parts.
[0026] It is provided in a further embodiment that a central nut shaft along the length of the machine, preferably driven at the end of the machine, is used as the drive shaft for the yarn processing devices. Fixed to this drive shaft in the region of the workstations is, in each case, at least one drive device, which is in turn connected by a continuous traction means and an associated output means to a yarn processing device, the continuous traction means being alternately guided to both machine sides. The yarn processing devices of the two machine sides of a textile machine can be driven simultaneously by a central nut shaft of this type.
[0027] When using a nut shaft of this type it is not only possible without problems to adjust the rotational direction of the yarn processing devices of the two textile machine sides by different crossings of the continuous traction means, but also a central adjustment of the working speed of the connected yarn processing devices is easily possible by means of the rotational speed of the central nut shaft. If these yarn processing devices, as, for example, known from two-for-one twisting or cabling machines, are configured as overfeed rollers, a central adjustment of the so-called overfeed factor of the numerous overfeed rollers can easily be realized.
[0028] It is furthermore provided in an advantageous embodiment that round belts are used as continuous traction means, the length of the round belt in the each case being more than four times the spacing provided between the center axis of the drive device and the center axis of the output means.
[0029] Round belts of this type are continuous traction means that have proven successful for a long time in mechanical engineering and are economical to obtain commercially as they are standardized mass produced parts. Moreover, round belts of this type, in particular if the continuous traction means has to be installed in the crossed state, have repeatedly proven to be successful in practice as a reliable drive means. In other words, round belts of this type are reliable and economical connection elements.
[0030] The yarn processing devices repeatedly described above, like the textile machines, may be configured very differently.
[0031] In conjunction with two-for-one twisting or cabling machines, the yarn processing devices, for example, may be configured as overfeed rollers, which preferably, as known, are overhung. In conjunction with such overhung over feed rollers, the output means, which are looped by the continuous traction means, are in each case mounted on easily accessible bearing shafts in such a way that, if necessary, both the continuous traction means and the output means can easily be exchanged. In other words, in this type of bearing arrangement, during a necessary intervention, all the rotating parts in the region of the overfeed roller can temporarily be shut down without problems, the handling at the overfeed roller also being simplified and the risk of injury therefore being minimized by the relatively large free space available.
[0032] However, instead of overfeed rollers, other yarn processing devices may also be used as yarn processing devices, which are driven by a continuous traction means installed according to the invention.
[0033] It is also certainly possible, for example to drive godets by a drive shaft of a textile machine, which is equipped with drive devices for guiding and entraining continuous traction means and has corresponding continuous traction means. The godets, which are preferably also overhung, are each provided here on their bearing axis with an output means.
[0034] A further use possibility for a drive device according to the invention also lies, for example, in the drive of waxing devices, as are known from various textile machines. Waxing devices of this type may also be advantageously driven by means of drive devices which are arranged on a drive shaft along the length of the machine and which are encompassed by continuous traction means installed according to the invention and act on output means connected to the waxing devices.
[0035] Independently of the respective type of yarn processing device, the configuration and arrangement according to the invention of drive devices arranged on a drive shaft along the length of the machine, in conjunction with corresponding output means in the region of the yarn processing devices and continuous traction means applied according to the invention, always allow a reliable and economical drive of yarn processing devices of this type.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] Further details of the invention will be described below with the aid of embodiments shown in the drawings, in which:
[0037] FIG. 1 schematically shows a side view of a multiple station textile machine, in the present embodiment a two-for-one twisting or cabling machine, with identical workstations arranged next to one another in the region of the longitudinal sides of the machine, yarn processing devices, in the present case overfeed rollers, arranged in the region of the workstations, in each case being connected in the configuration according to the invention by a continuous traction means to a drive shaft, in the embodiment to one of the friction shafts, of the multiple station textile machine,
[0038] FIG. 2 shows, in detail, a first embodiment of the attachment according to the invention, indicated schematically in FIG. 1 , of an overfeed roller to one of the friction shafts of a two-for one twisting or cabling machine,
[0039] FIG. 3 shows, in detail, a second embodiment of an attachment according to the invention of an overfeed roller to a friction shaft of a two-for one twisting or cabling machine,
[0040] FIG. 4 shows, in detail, a further embodiment of the attachment according to the invention of overfeed rollers to a drive shaft, the drive shaft being configured as a central nut shaft in the present embodiment,
[0041] FIG. 5A shows a first embodiment of a drive device installed in the region of a friction shaft,
[0042] FIG. 5B shows a second embodiment of a drive device installed in the region of a friction shaft,
[0043] FIG. 6 shows an output means installed in the region of a bearing shaft of a yarn processing device, for example an overfeed roller,
[0044] FIG. 7 shows a continuous traction means while being placed on a drive device or shortly before being drawn onto an associated output means.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0045] FIG. 1 schematically shows a side view of a multiple station textile machine, a two-for-one one twisting or cabling machine 1 in the embodiment. As known, textile machines of this type have a large number of workstations 2 , which are arranged next to one another on both sides of the longitudinal axis of the machine. The workstations 2 of two-for-one twisting or cabling machines 1 of this type are in each case inter alia equipped with a two-for-one twisting device 3 and a winding mechanism 4 . In the embodiment shown in FIG. 1 , a yarn 6 drawn from a two-for-one one twisting spindle 5 runs via a yarn guide 7 , which limits a yarn balloon 8 being produced in the region of the twisting device 3 with respect to its height during the twisting operation, to the winding mechanism 4 , where the yarn 6 is wound to form a cross-wound bobbin 10 .
[0046] The winding device 4 , as conventional, has a creel 12 to rotatably hold the cross-wound bobbin 10 , the creel 12 being liftable, if necessary, by means of a pneumatic cylinder 18 .
[0047] Furthermore, the winding mechanism 4 has a friction roller 13 fixed on a continuous friction shaft 14 to rotate the cross-wound bobbin 10 in the rotational direction R and a yarn traversing device 11 to traverse the yarn 6 that is traveling to and being wound onto the bobbin.
[0048] A yarn processing device 41 , an overfeed roller 9 in the embodiment, is arranged in the yarn running direction F before the yarn traversing device 11 and is connected by a continuous traction means 19 , drawn up according to the invention, to a drive shaft along the length of the machine, in the embodiment of FIG. 1 to a friction shaft 14 of the relevant machine side of the multiple station textile machine 1 .
[0049] Arranged between the yarn guide 7 and the overfeed roller 9 is furthermore a yarn sensing device 15 , which monitors the proper running of the yarn 6 during the twisting process. The yarn sensing device 15 , which is connected by a signal line 16 to the control device 17 , detects yarn breaks occurring during the twisting operation and signals this immediately, in each case, to the control device 17 , which thereupon initiates a loading of the associated pneumatic cylinder 18 with pressure by means of the control line 21 . In other words, when a yarn break occurs, the creel 12 is pivoted up and the cross-wound bobbin 10 is thereby lifted from the revolving friction roller 13 . After the elimination of the yarn break, the creel 12 is lowered again, so the cross-wound bobbin 10 rests on the friction roller 13 again and can again be rotated thereby by frictional engagement in the direction R.
[0050] As schematically shown in FIG. 1 , drive devices 20 , which are in each case connected by a specially arranged continuous traction means 19 and an associated output means 22 to one of the yarn processing devices 41 , overfeed rollers 9 in the embodiment, are fixed on the friction shafts 14 along the length of the machine and acting as drive shafts. The overfeed rollers 9 in two-for-one twisting or cabling machines, as is known, serve to reduce the yarn tension of the yarn 6 to be wound on, which, after cabling or twisting, has a yam tension, the so-called balloon tension, which is above the yarn tension reasonable to build up a cross-wound bobbin 10 . To reduce this excess yam tension, the overfeed roller 9 , which is at least partially looped by the yarn 6 , is driven at a peripheral speed, which is greater than the yarn speed of the yam 6 running on to the cross-wound bobbin 10 . This means that the balloon tension is reduced because of the peripheral speed of the overfeed roller 9 , which is higher in relation to the yarn speed, and the degree of looping of the yarn 6 around the overfeed roller 9 , until a yarn tension reasonable for the build-up of a proper cross-wound bobbin 10 is present. As can also be seen, in particular from FIG. 2 , the overfeed roller 9 is preferably in each case arranged axially parallel to the friction shaft 14 on a carrier 23 .
[0051] To simplify the assembly and disassembly of the overfeed roller 9 , an overhung arrangement of the overfeed roller 9 is provided in an advantageous embodiment. An output means 22 is non-rotatably installed on the bearing shaft 25 of the overhung overfeed roller 9 , which output means, as can be seen from FIG. 6 , has two adjacently arranged deflection and guide grooves 26 A, 26 B for two strands of the continuous traction means 19 and a suitable shaft/hub connection, for example a threaded bore 27 , for a clamping screw or the like, to fix the output means 22 to the bearing shaft 25 .
[0052] The associated drive devices 20 which, as shown in FIGS. 5A , 5 B, are at least partially configured as a belt pulley device 40 , may also have various embodiments. All the embodiments have a base body 28 , which can be fixed by means of a threaded bore 29 and a clamping screw or the like on the friction shaft 14 in a non-rotatable manner.
[0053] As shown in FIG. 5A , the base body 28 , in a first embodiment, is equipped with a deflection and guide groove 30 for the strand to be driven of the continuous traction means 19 and with a bearing attachment 31 for a bearing 32 , which is preferably configured as a roller bearing or as a sliding bearing. In the present embodiment, fixed on the outer ring of a roller bearing 32 , is a so-called loose wheel 33 , which has a deflection and guide groove 34 for a second strand, which runs counter to the drive direction of the yam processing device 41 , of the same continuous traction means 19 .
[0054] In the second embodiment of a drive device 20 shown in FIG. 5B , the deflection and guide groove 30 for the strand to be driven of the continuous traction means 19 is integrated into the friction roller 13 . Fixed closely next to the friction roller 13 on the friction shaft 14 in a non-rotatable manner is a base body 28 , which has a bearing 32 , for example a roller bearing or a sliding bearing.
[0055] As known from the embodiment according to FIG. 5A , a so-called loose wheel 33 , which has a deflection and guide groove 34 for the second strand of the continuous traction means 19 running in the opposite direction, is fastened to the outer ring of the roller bearing 32 .
[0056] As shown, for example in FIG. 2 , the continuous traction means 19 in the arrangement according to the invention, after being drawn onto the drive device 20 and the output means 22 , is in each case located with its two strands in the deflection and guide grooves of the presently described components.
[0057] During assembly of the continuous traction means 19 , the continuous traction means 19 , as shown in FIG. 7 , is firstly placed in the rear receiving groove 26 B of the output means 22 , in relation to the carrier 23 , not shown in FIG. 7 . The continuous traction means 19 is then drawn around the drive device 20 fixed to the friction shaft 14 along the length of the machine in such a way that two adjacent strands of the continuous traction means 19 encompass the drive device 20 , which, for example, has the embodiment shown in FIG. 5A . In other words, the rear strand of the continuous traction means 19 in relation to the friction roller 13 is placed in the deflection and guide groove 34 of a loose wheel 33 rotatably mounted on the base body 28 of the drive element 20 , while the front strand of the continuous traction means 19 is positioned in the belt receiving groove 30 of the base body 28 of the drive device 20 . The two strands of the continuous traction means 19 are then twisted lengthwise relative to one another about their common longitudinal axis by a 180 degree rotation of the strands between the drive shaft 35 and the other end loop and the other end loop is placed in this state in the front receiving groove 26 A of the output means 22 . In this manner, the end loops travel in the same direction as one another in the grooves 26 A, 26 B.
[0058] In the embodiment shown in FIGS. 2 and 5A , the drive device 20 is in each case completely configured as a separate belt pulley device 40 , which is fastened at a spacing next to the friction roller 13 on the friction shaft 14 . In other words, the belt pulley device 40 has a base body 28 with a deflection and guide groove 30 , a bearing 32 and a loose wheel 33 with a deflection and guide groove 34 and is non-rotatably fixed with its base body 28 by a shaft/hub connection, for example, on a friction shaft 14 acting as a drive shaft 35 . In an alternative embodiment, shown in FIGS. 3 and 5B , the drive device 20 is partially integrated into the friction roller 13 . In other words, the friction roller 13 has a deflection and guide groove 30 , into which the strand of the continuous traction means 19 to be driven in the drive direction AR is placed. A belt pulley device 40 is additionally arranged directly next to the friction roller 13 on the friction shaft 14 , on the base body 28 of which belt pulley device a loose wheel 33 is freely rotatably mounted by a roller bearing 32 , in the deflection and guide groove 34 of which the second strand of the continuous traction means 19 is mounted in such a way that it can revolve counter to the drive direction AR of the yarn processing device 41 .
[0059] FIG. 4 shows an embodiment, in which a central nut shaft along the length of the machine is used as the drive shaft 35 instead of the friction shafts 14 arranged on the machine sides A and B of the multiple station textile machine 1 . As already stated above in conjunction with the friction shafts 14 configured as drive shafts 35 , a large number of drive devices 20 , which are in each case connected by a continuous traction means 19 to an output means 22 of a yarn processing device 41 , also an overfeed roller 9 in the present embodiment, are also fixed on this central drive shaft 35 . In this arrangement, the drive devices 20 or the output means 22 preferably have the embodiments shown in FIG. 5A or FIG. 6 . The embodiment shown in FIG. 4 , in particular, has the advantage that in an arrangement of this type, the rotational direction of the yarn processing devices 41 can easily be properly adjusted by a corresponding crossing of the continuous traction means 19 .
[0060] FIG. 6 shows, partially in section, an output means 22 , the base body 28 of which can be fixed by means of a shaft/hub connection, for example by means of a clamping screw (not shown), which corresponds with the threaded bore 27 , on the bearing shaft 25 of a yarn processing device (not shown). The base body 28 has two deflection and guide grooves 26 A and 26 B arranged in parallel next to one another for two strands, which are loaded in the drive direction, of a continuous traction means 19 .
[0061] It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. | A textile machine with multiple workstations equipped with a yarn processing device, and a drive shaft extending along multiple workstations, each yarn processing device connected to the drive shaft by a continuous traction means, and the drive shaft including multiple drive devices each guiding a continuous traction means. Each drive device has two grooves coaxially to the drive shaft, one of the grooves being part of a free wheel about the drive shaft. An output means is connected to each yarn processing device, each output means having front and rear guide grooves, the front groove at a free end of the output means and the rear groove adjacent the associated yarn processing device. Each traction means has one loop engaged in the rear groove of the associated output means and another loop engaged in the front groove through 180 degrees. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present patent application is a continuation of U.S. patent application Ser. No. 11/681,060 filed Mar. 1, 2007, which in turn is a continuation-in-part of and claims priority from U.S. patent application Ser. No. 11/162,499 filed Sep. 13, 2005, which in turn is a continuation in-part of and claims priority from U.S. Provisional Patent Application Ser. No. 60/609,427 filed Sep. 13, 2004, the entire contents of which applications are incorporated herein by reference thereto.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC
[0003] Not applicable.
BACKGROUND OF THE INVENTION
[0004] The present invention relates generally to a reclosable fastener riser/spacer device, and methods of constructing and using same.
[0005] More particularly, the present invention relates to an extruded plastic spacer/riser device to increase the useable height of reclosable fastening systems, such as, for example, 3M™ Dual Lock™ or Velcro® hook and loop products, and methods of constructing and utilizing same.
[0006] The term “reclosable fastener” as used herein means 3M™ Dual Lock™ fasteners, Velcro®hook and loop fasteners, and any other fastener that is selectively reclosable.
[0007] Typically, reclosable fastening systems, such as, for example, 3M™ Dual Lock™ or Velcro® hook and loop products, are limited in their overall height or thickness in application.
[0008] Many times there is a need to increase the overall height or thickness of these fasteners.
[0009] For example, when using a reclosable fastener for fastening together the headliner of an automobile and the sheet metal portion roof of the automobile, oftentimes there is a space or gap between the parts of the reclosable fasteners which might necessitate the pushing in of the headliner, resulting in an uneven look with creases and folds and the like.
[0010] The present invention provides a device to increase the overall height, allowing more versatility in the use of reclosable fasteners in many different applications.
[0011] It is a desideratum of the present invention to avoid the animadversions of conventional reclosable fastening systems which are limited in their overall height or thickness in application.
BRIEF SUMMARY OF THE INVENTION
[0012] The present invention provides a riser/spacer device for use with a reclosable fastener, comprising, in combination: a riser/spacer device a having a first predetermined overall height, and first and second predetermined portions; a reclosable fastener having a second predetermined overall height, and selectively closable and releasable first and second mating portions; said first mating portion of said reclosable fastener being secured to said first predetermined portion of said riser/spacer device; said first predetermined overall height of said riser/spacer device plus and said second predetermined overall height of said reclosable fastener being determined by a gap to be filled between first and second external substrates; said second predetermined portion of said riser/spacer device being connected, directly or indirectly, to said first external substrate; and said second mating portion of said reclosable fastener being connected, directly or indirectly, to said second external substrate.
[0013] The present invention also provides a method of fabricating a riser/spacer device, comprising the steps of: softening plastic in an extruder as said plastic is forced though said extruder by an extruder screw toward a die; shaping said softened plastic in said die; holding the shape of said plastic with shaping tooling and guides as said softened shaped plastic exits said die in a continuous length until said softened shaped plastic is cooled and set to a required shape and dimensions of said riser/spacer device; and maintaining the size of the plastic riser/spacer device by a ratio between the amount of plastic being forced through said die and the speed of a haul off apparatus pulling the plastic riser/spacer device away from said die and through shaping tooling and guides.
[0014] The invention also provides a riser/spacer device which includes first and second mating channel members which are designed and dimensioned to be slidably assembled and disassembled together; and said first and second mating channel members are disposed between said first mating portion of said reclosable fastener and said first external substrate.
[0015] The present invention further provides an extruded spacer/riser device as described hereinabove to increase the useable height of reclosable fastening systems, such as, for example, 3M™ Dual Lock™ or Velcro® hook and loop products.
[0016] It is a primary object of the present invention to provide a reclosable fastener riser/spacer product as described hereinabove, wherein such riser/spacer product may be fabricated by extrusion out of materials such as ABS, polypropylene, polyethylene, or any suitable material.
[0017] Another object of the present invention is to provide such a riser/spacer device as described hereinabove, which allows reclosable fastening systems to have more versatility in applications.
[0018] Another object of the present invention is to provide such a riser/spacer device as described hereinabove, wherein the riser/spacer device is designed to be held in place on a substrate with hot-melt glue, sonic welding, pressure sensitive adhesive, acrylic foam tape, screws, or other securement means.
[0019] The foregoing objects, advantages and features of the present invention will become apparent to those persons skilled in this particular area of technology and to other persons after having been exposed to the following detailed description of the present invention and when read in conjunction with the accompanying patent drawings.
[0020] For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, which show some preferred embodiments of the present invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0021] FIG. 1 illustrates a top plan view of a spacer/riser device in accordance with a first embodiment of the invention.
[0022] FIG. 2 shows a front elevational view of the FIG. 1 device.
[0023] FIG. 3 shows a side elevational view of the FIG. 1 device.
[0024] FIG. 4 illustrates a bottom view of the FIG. 1 device.
[0025] FIG. 5 is a view similar to FIG. 2 but showing the internal structure of the spacer in phantom line.
[0026] FIG. 6 is a view similar to FIG. 3 but showing the internal structure of the spacer in phantom line.
[0027] FIG. 7 is an isometric drawing showing the device having affixed thereon one portion of a 3M™ Dual Lock™ reclosable fastener.
[0028] FIG. 8 shows a side elevational view, partly in section, of the riser/spacer device of the present invention as used with a particular reclosable fastener system.
[0029] FIG. 9 illustrates a perspective view of a second embodiment of the invention.
[0030] FIG. 10 shows an end view of the FIG. 9 embodiment.
[0031] FIG. 11 illustrates a third embodiment.
[0032] FIG. 12 shows a device for mating with the FIG. 11 embodiment.
[0033] FIG. 13 depicts a bottom view of the FIG. 12 device.
[0034] FIG. 14 is a front view of the FIG. 12 device inverted.
[0035] FIG. 15 is view of the unassembled dual-lock fastener of FIGS. 12-14 .
[0036] FIG. 16 shows the FIG. 15 fastener on acrylic foam tape.
[0037] FIG. 17 is a side view of FIG. 14 .
[0038] FIG. 18 shows a top view of the unassembled acrylic foam tape of the FIG. 11 device.
[0039] FIG. 19 is a front view of FIG. 18 .
[0040] FIG. 20 is a partial perspective view of a fourth embodiment of the invention.
[0041] FIG. 21 is front view of FIG. 20 .
[0042] FIG. 22 is a front view of a first channel portion of FIG. 20 .
[0043] FIG. 23 is a front view of second channel portion which mates with FIG. 22 device.
[0044] FIG. 24 is a partial perspective view of a fifth embodiment of the invention.
[0045] FIG. 25 is front view of FIG. 24 .
[0046] FIG. 26 is a front view of a first channel portion of FIG. 24 .
[0047] FIG. 27 is a front view of second channel portion which mates with FIG. 26 device.
DETAILED DESCRIPTION OF THE INVENTION
[0048] Similar components in the various embodiments are designated by the same reference numbers, unless indicated otherwise.
[0049] The invention provides a riser/spacer device 18 for use with a reclosable fastener 17 , wherein: the riser/spacer device has a first predetermined overall height, and first and second predetermined portions 19 and 26 ; the reclosable fastener 17 has a second predetermined overall height, and selectively closable and releasable first and second mating portions 16 and 22 ; said first mating portion 16 of said reclosable fastener 17 being secured to said first predetermined portion 19 of said riser/spacer device 18 ; said first predetermined overall height of said riser/spacer device 18 plus and said second predetermined overall height of said reclosable fastener 17 being determined by a gap to be filled between first and second external substrates 20 and 23 ; said second predetermined portion 26 of said riser/spacer device 18 being connected to said first external substrate 20 ; and said second mating portion 22 of said reclosable fastener 17 being connected to said second external substrate 23 .
[0050] With reference to FIGS. 1-8 , there is illustrated a first embodiment of the present invention in the form of an unitarily-molded riser/spacer device 18 having a main spacer retainer member 10 and a spacer 15 .
[0051] Preferably, but not necessarily, the main spacer retainer member 10 is provided around its outer periphery 11 with a series of apertures 12 .
[0052] The main spacer retainer member 10 is provided with a predetermined portion or base member 26 having a lower surface 27 , as best shown in FIG. 8 .
[0053] The main spacer retainer member 10 surrounds one or more spacer members 15 , the height of which is dependent upon the increase in height or gap to be filled between external substrates 20 and 23 .
[0054] Preferably, but not necessarily, the device 18 is injection molded from materials such as ABS, polypropylene, polyethylene, or other plastics.
[0055] With reference to FIG. 7 , there is shown the device 18 having affixed at a predetermined portion or top surface 19 thereof a first mating portion 16 of a reclosable fastener 17 , such as a 3M™ Dual Lock™ reclosable fastener.
[0056] With reference to FIG. 8 , there is shown the device 18 having the lower surface portion 27 of its base number 26 secured to a first external substrate 20 , such as the sheet metal roof of an automobile, by hot-melt glue, sonic welding, pressure-sensitive adhesive, or other securement means 21 .
[0057] A second portion 22 of the reclosable fastener 17 , such as a 3M™ Dual Lock™ reclosable fastener, is secured to a second external substrate 23 , such as, for example, the headliner of an automobile by hot-melt glue, sonic welding, pressure-sensitive adhesive, or other securement means 28 .
[0058] With reference to FIGS. 7 and 8 , the purpose of the apertures 12 in the main spacer retaining member 10 is to permit hot-melt glue or other adhesive to move therethrough, or screws to pass therethrough, when securing member 10 to an external substrate 20 .
[0059] With reference to FIG. 8 , the 3M™ Dual Lock™ reclosable fastener 17 will operate in the normal fashion with the mushroom heads 25 on the rigid plastic stems 24 releasably interlocked. The 3M™ Dual Lock™ reclosable fasteners 17 are self-mating, that is the fasteners 17 simply reattach to themselves. When pressed together, thousands of mushroom heads 25 interlock with one another creating an audible snap that announces that the fastener portions 16 and 22 are interlocked.
[0060] FIGS. 9 and 10 a riser/spacer device 40 in accordance with a second embodiment of the invention.
[0061] The riser/spacer device 40 is made by an extrusion process as described hereinbelow. In the extrusion process in accordance with the present invention, the plastic from which the device 40 is made has to be softened so it can be shaped. This can be done by any suitable means, such as, for example, by applying heat.
[0062] In accordance with the invention, this softening of the plastic takes place in an extruder as the plastic is forced toward and through a die by an extruder screw. The shape is imparted to the plastic by the die.
[0063] Once the plastic exits the die in a continuous length, it is held or maintained in shape with shaping tooling and guides until the plastic material can be cooled and set to the required shape.
[0064] The size of the plastic part is maintained by a ratio between the amount of plastic being forced through the die and the speed of an haul off apparatus which pulls the part away from the die and through the shaping tooling.
[0065] After the part shape has been set, any number of process steps can be done to the part while it is still in a continuous length and before it passes through the haul off apparatus. In the case of the riser/spacer device 40 , these process steps may preferably, but not necessarily, include applying promoter, applying a portion 41 (similar to portion 16 described above) of a reclosable fastener 17 , and applying a part identification.
[0066] Once the part is beyond the haul off apparatus, it may be cut to the required length, yielding the finished part.
[0067] With reference to FIGS. 9 and 10 , the riser/spacer device 40 includes a reclosable fastener somewhat similar to the reclosable fastener 17 described above in connection with FIGS. 7 and 8 . The reclosable fastener 17 has a predetermined overall height “a” (as shown in FIG. 8 ), and a selectively closable and releasable first and second mating portions.
[0068] Also, as shown in FIG. 8 , the predetermined overall height of the riser/spacer device plus and the predetermined overall height “a” of the reclosable fastener is determined by a gap “b” to be filled between first and second external substrates 20 and 23 .
[0069] As shown in FIG. 8 , a mating portion 22 of the reclosable fastener 17 is secured to an external substrate 23 .
[0070] The mating portion 41 ( FIGS. 9 and 10 ) is similar to the mating portion 16 .
[0071] FIGS. 11-19 illustrate a third embodiment 50 having first and second riser/spacer devices 51 and 52 , and a reclosable fastener 17 . FIG. 11 show mating portion 16 of fastener 17 mounted on spacer 51 , which in turn is mounted on acrylic foam tape member 53 .
[0072] FIG. 12 shows the device for mating with the FIG. 11 device. FIG. 12 shows mating portion 22 of fastener 17 secured to spacer 52 , which in turn is secured to acrylic foam tape member 54 .
[0073] FIG. 13 depicts a bottom view of the FIG. 12 device.
[0074] FIG. 14 is a front view of the FIG. 12 device inverted.
[0075] FIG. 15 is view of the unassembled dual-lock fastener of FIGS. 12-14 .
[0076] FIG. 16 shows the FIG. 15 fastener on acrylic foam tape.
[0077] FIG. 17 is a side view of FIG. 14 .
[0078] FIG. 18 shows a top view of the unassembled acrylic foam tape of the FIG. 11 device.
[0079] FIG. 19 is a front view of FIG. 18 .
[0080] FIG. 20 is a partial perspective view of a fourth embodiment 60 of the invention.
[0081] FIG. 21 is front view of FIG. 20 .
[0082] FIG. 22 is a front view of a first channel portion 61 of FIG. 20 .
[0083] FIG. 23 is a front view of second channel portion 62 which mates with the FIG. 22 device.
[0084] FIG. 24 is a partial perspective view of a fifth embodiment 70 of the invention.
[0085] FIG. 25 is front view of FIG. 24 .
[0086] FIG. 26 is a front view of a first channel portion 71 of FIG. 24 .
[0087] FIG. 27 is a front view of second channel portion 72 which mates with the FIG. 26 device.
[0088] With reference to the fourth and fifth embodiments 60 and 70 , respectively, it should be noted that the device includes first and second mating channel members which are designed and dimensioned to be slidably assembled and disassembled together; and said first and second mating channel members are disposed between said first mating portion of said reclosable fastener and said first external substrate.
[0089] While the present invention has been described hereinabove with respect to several preferred embodiments for illustrative purposes only, it should be understood that the present invention encompasses and embraces all modifications, variations, and changes in the basic inventive concept.
[0090] Also, the variations and modifications are intended to be embraced within the scope of the present invention and the patent claims set forth hereinbelow. | A plastic spacer/riser to increase useable height of a reclosable fastening system, such as 3M™ Dual Lock™ or Velcro® hook and loop products. The spacer/riser is adapted to be held in place on an external substrate with hot-melt glue, sonic welds, pressure-sensitive adhesives, acrylic foam tape, or screws. | 8 |
FIELD OF THE INVENTION
This invention relates to noise-canceling telephonic handsets, and more specifically to those that employ feed-forward cancellation techniques.
ART BACKGROUND
The utility of telephonic handsets, such as cellular terminals and cordless telephones, in noisy environments is limited by the interfering noise that is passed to the user's ear. To improve the intelligibility of arriving far-end speech in such environments, handsets of the prior art have incorporated such expedients as a volume control to increase the incoming sound signal level relative to the noise signal level.
Another expedient is active cancellation of the ambient acoustic noise pressure relative to the incoming speech acoustic pressure within the user's ear. One approach to active noise cancellation is described, for example, in U.S. Pat. No. 5,491,747, issued on Feb. 13, 1996 to C. S. Bartlett et al. under the title “Noise-Cancelling Telephone Handset”, and commonly assigned herewith.
In typical applications of active noise cancellation, a microphone picks up the ambient noise pressure and generate a signal that is fed into a noise canceling circuit. This circuit creates a noise inverted signal that is applied to the handset receiver. (In this context, the “receiver” is a loudspeaker or other electric-to-acoustic transducer for projecting the received audio signal into the user's ear.) The receiver acoustic output subtractively interferes with the ambient noise pressure, thus reducing the noise level in the user's ear.
It is well known that active noise canceling techniques may be either of a negative feedback design or a feed-forward design. Both of these approaches are described, for example, in P. A. Nelson and S. J. Elliot, Active Control of Sound , Academic Press, 1992. Although the viability of feed-forward designs has been recognized, negative feedback designs have generally been preferred for use in telephonic equipment, such as in headset earpieces. Such a preference is due, in part, to the greater robustness that negative-feedback designs tend to exhibit against inter-user variability. This preference is also due, in part, to the relative ease with which these designs may be implemented in analog circuitry, and to a general perception that feed-forward designs provide an inferior level of noise cancellation. An illustrative negative feedback system of the prior art is shown in FIG. 1 .
There has also been a general perception that a feed-forward design can be made robust against inter-user variability only by incorporating adaptive circuitry. However, as a practical matter, such an expedient would call for a digital signal processor (DSP) having two analog-to-digital converters (ADCs)—one each for the reference microphone and the error microphone, respectively, and one digital to analog converter (DAC) to generate the canceling noise signal for the handset receiver. Although recent digital cellular terminals do in fact include a DSP, the requisite number of ADCs is not generally present. Additionally, the computational capacity of the terminal DSP is substantially taken up by the other voice processing functions required by the terminal. Thus, very little computational capacity is left over for implementation of an active noise canceling function. Although there are commercially available some DSPs that have been designed specifically for active noise cancellation, the computational capacity of even these devices is limited as a result of pressure to keep the cost within bounds of commercial feasibility.
Despite their reputed advantages, negative feedback noise canceling designs suffer from certain disadvantages as well. For example, to avoid a potential instability, it is generally desirable to set the feedback gain to a level that is lower than optimum, leading to some performance degradation.
This and other disadvantages could be overcome by a computationally efficient feed-forward noise cancellation design suitable for implementation on a DSP.
SUMMARY OF THE INVENTION
We have provided such a design. Our design is a fixed feed-forward design that can perform effective noise cancellation and that is robust against inter-user variability. Because our design is fixed, and not adaptive, the DSP does not suffer the burden of adding an adaptive filter to the DSP software. Moreover, although a noise reference microphone is required, there is no need to include an error microphone. Consequently, parts costs and assembly costs can be reduced relative to adaptive designs.
Significantly, we have discovered that human behavior is a natural ally in the quest to reduce inter-user variability. That is, the user of a fixed (i.e., non-adaptive) feed-forward noise canceling handset tends to instinctively position the earpiece of the handset on the ear so that noise cancellation performance is maximized. It is a matter of common experience that the human brain is adept at tuning a radio dial to maximize the signal-to-noise ratio of sensory input. Our discovery shows that the brain can also provide the adaptivity required to make a fixed feed-forward system not only feasible, but also highly effective and robust.
The co-pending U.S. patent application Ser. No. 09/055,481, filed on Apr. 6, 1998 by C. S. Bartlett et al. under the title “Telephonic Handset Apparatus Having an Earpiece Monitor and Reduced Inter-User Variability” and commonly assigned herewith, describes a physical handset arrangement that reduces inter-user variability. The present invention has utility independent of such handset arrangement and need not be used conjointly with it. However, these approaches are at least partly complementary, and their combined use is especially advantageous.
In one aspect, our invention involves a telephonic handset, such as a mobile wireless terminal, that comprises an active noise reduction (ANR) system. The ANR system comprises a reference microphone and an IIR filter. The IIR filter is receivingly coupled to the reference microphone with respect to noise reference signals, and it is transmittingly coupled to the receiver transducing element of the handset. The ANR system is configured as a fixed feed-forward noise cancellation system.
In preferred embodiments of the invention, the IIR filter has a transfer function derived, in part, from the open-loop gain of a feedback noise cancellation system.
In specific embodiments of the invention, the noise reference microphone is situated so as to sample the ambient noise field near the front face of the receiver, but without directly sampling the noise field on the front face. Thus, in exemplary embodiments, the port of the reference microphone opens onto a side-facing or rear-facing external surface of the handset. In this context, the front-facing direction is the direction facing toward the user's ear.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic representation of a negative feedback active noise reduction (ANR) design of the prior art.
FIGS. 2A and 2B are partially schematic, cross-sectional diagrams of illustrative fixed feed-forward ANR designs installed within a mobile wireless terminal, having two respective, exemplary placements for the noise reference microphone.
FIGS. 3A and 3B are schematic block diagrams of a feed-forward noise cancellation system, showing, respectively, digital and analog summation of the far-end speech signal.
FIG. 4 is a plot, from experimental data, of the coherence (as a function of frequency) between the noise field at a reference microphone within a telephone handset and the noise field within the opening to the user's ear canal.
FIG. 5 . is a graph, versus frequency, of the transfer function Y(ω), which represents the ratio of acoustic pressure output by the receiver of a telephonic handset to the electrical input. Plotted on the graph is this transfer function, for five distinct users.
FIG. 6 . is a graph, similar to the graph of FIG. 5 , but representing the case in which a prior-art technique of electro-acoustic modification is applied in the handset.
FIG. 7 . shows the average noise-cancellation performance and standard deviation of a fixed feed-forward noise canceling design, according to the present invention, for five distinct users.
DETAILED DESCRIPTION
Turning to FIGS. 2A and 2B , an illustrative feed-forward noise canceling system according to the present invention includes an electronic processing module 4 , receivingly connected to noise reference microphone 3 , and transmittingly connected to receiver 5 . Module 4 is also in receiving relationship to far-end signal path 8 . Each of the respective FIGS. 2A and 2B depicts an alternative arrangement in which the noise-canceling system is installed within a telephonic handset 7 (exemplarily, a wireless mobile terminal), and the handset positioned near a user's ear-canal opening 9 . In FIG. 2A , microphone 3 is situated at a side face of the handset. In FIG. 2B , microphone 3 is situated at a rear face. (In this context, the “front” face is the face directed toward the user's ear when the handset is in use.) It should be understood that various other placements for the reference microphone will also be acceptable. General principles for the advantageous placement of this microphone are set out below.
The operation of a feed-forward noise canceling systems in general has been described in well-known references such as the above-cited book by Nelson and Elliot. Briefly, noise reference microphone 3 senses ambient noise 1 and, in response, generates a signal to be acted upon by electronics module 4 . Module 4 generates a noise canceling signal according to well-known principles. The noise canceling signal is fed to receiver 5 . The acoustic output of receiver 5 subtractively interferes with ambient acoustic noise 2 within the user's ear canal opening 9 . As a result, at least a portion of the ambient noise is canceled.
Receiver 5 may be mounted upon a compact electro-acoustic module 6 , as described in co-pending patent application Ser. No. 09/055,481, cited above. Such a module 6 is designed to reduce inter-user variations produced by the variable leak, 19 , between the earpiece of the handset and the user's ear. The processing electronics function of module 4 , required to achieve feed-forward noise cancellation, is preferably implemented by a digital signal processor (DSP), although other components, such as analog components, may also be used for such implementation.
For analytical purposes, a feed-forward noise canceling system is conveniently represented by a system block diagram in which a frequency-domain transfer function represents the operation of each component upon signals. FIGS. 3A and 3B are system block diagrams that represent alternate DSP implementations of a feed-forward noise canceling system.
With reference to FIGS. 3A and 3B , receiver 5 is there represented by transfer function Y(ω) (block 11 ), which is a ratio obtained by taking the acoustic pressure output into the ear at point 9 of FIGS. 2A and 2B (as it would be measured by a small microphone), and dividing it by the input signal fed to receiver 5 . Similarly, the ratio of the output signal to the input signal of processing electronics module 4 may be represented as transfer function W FF (ω). The feed-forward design is referred to as “fixed” when this transfer function W FF (ω) is constant over time.
As a practical matter, the respective transfer functions of ADC 13 for the noise reference signal, ADC 14 for the far-end speech input signal, and DAC 15 for the output to the receiver, may generally be approximated as unity.
In FIG. 3A , the far-end speech signal, received on path 8 , is digitized by ADC 14 and added digitally (i.e., as data under control of the DSP software) at summing point 12 to the digital input stream to DAC 15 . At the summing point, the far-end signal is added to the noise reference signal, which has been processed in accordance with transfer function W FF (ω).
By contrast, in FIG. 3B , the far-end signal is added, as an analog signal, at summing point 18 , which follows DAC 15 .
The arrangement of FIG. 3A calls for a DSP having two ADCs, whereas the arrangement of FIG. 3B does not require the DSP to have more than one ADC.
The noise cancellation performance of a feed-forward system is well known to depend upon the coherence (which is preferably as close to unity as possible) between the ambient noise 1 picked up by noise reference microphone 3 , and the ambient noise 2 at the point where noise cancellation is desired. (This is discussed, e.g., by the above-cited book by Nelson and Elliot at page 177.) In the case of a telephone handset such as a cellular terminal, the desired point of noise cancellation is the user's ear canal opening 9 .
We performed coherence measurements in a diffuse ambient noise field, using an arrangement such as that of FIG. 2B , in which reference microphone 3 is situated on the rear face of the handset. Ambient noise 2 was measured at point 9 using a small electret microphone. The results of these measurements are shown in FIG. 4 .
It is evident from the figure that the coherence is approximately unity over a frequency range up to about 1 kHz. This supports our belief that effective feed-forward noise cancellation is attainable, on a telephone handset, at least up to 1 or 2 kHz. Because the measured coherence begins to fall off at frequencies above about 1 kHz, and falls off both more irregularly and, on the average, more rapidly above about 2 kHz, we would expect the best performance to be obtained at frequencies below 2 kHz.
We also measured the coherence between ambient noise 2 at the user's ear canal opening 9 , and ambient noise 1 at the reference microphone. We found that this coherence tends to decrease, over all frequencies, as the separation between microphone 3 and measurement point 9 is increased. This result militates for situating noise reference microphone 3 in such a way that its port 20 samples the ambient noise field as close as is practicable to the front face of the receiver.
However, port 20 should not sample the noise field directly at the front face of the receiver. This is undesirable because it can result in the microphone picking up a substantial amount of acoustic output from receiver 5 . This can cause the noise-cancellation performance to degrade, and in the worst cases, it can lead to an unstable feedback loop which may cause audible oscillations. We would consider the amount of feedback to be “substantial” if perceptible degradation in performance occurred. (It should be noted in this regard that the feed-forward system can generally tolerate a small amount of feedback, but feedback in such a system is not provided intentionally, because it does not help performance, and generally tends to degrade it.)
Thus, depending upon the space available inside the handset, microphone 3 will typically be mounted on the inner surface of a side or rear wall of the handset housing; i.e., a wall whose outer surface faces sideward or rearward. Thus, the microphone port will open through such a side or rear wall.
The maximum acceptable effective separation between the receiver element and the sampling point for ambient noise (i.e., port 20 ) depends upon the desired degree of noise cancellation. As a general rule, this separation is preferably no more than about 3.8 cm, and even more preferably, no more than about 2.5 cm. In this context, the “effective” separation is the distance between port 20 and point 9 ; i.e., the point at the entrance to the user's ear canal that lies just in front of the receiver element when the handset is in use.
With reference to FIGS. 3A and 3B , we now consider the residual acoustic noise pressure ε at point 9 , in the user's ear canal opening, due to noise field 2 having acoustic pressure n 2 , and noise field 1 , having acoustic pressure n 1 . If there is no far-end speech signal, this residual acoustic pressure is given by:
ε= n 2 −Y (ω) W FF (ω) n 1 . (1)
If the noise fields having respective acoustic pressures n 1 and n 2 are highly coherent, then n 2 must be related to n 1 by a transfer function F(ω). Then, equation (1) may be rewritten as
ε=[ F (ω)− Y (ω) W FF (ω)] n 1 . (2)
In order to reduce the residual acoustic noise pressure ε at point 9 to zero, the optimal feed-forward filter W FFOPT (ω), implemented in the DSP, ideally should satisfy
W FFOPT (ω)= F (ω)/ Y (ω). (3)
If the phase slope (or time delay) of Y(ω) were significantly greater than that of F(ω), then the feed-forward filter, W FFOPT (ω), would need to be anti-causal to achieve noise cancellation. As a general rule, this cannot be achieved in practice. Therefore, for there to be effective feed-forward noise cancellation, it is desirable to select receiver 5 to have minimal time delay (or phase slope) over as broad a frequency band as possible. Because, as a practical matter, this cannot be perfectly achieved, some compromise in noise cancellation performance must be expected.
Moreover, as discussed earlier, transfer functions F(ω) and Y(ω) will generally vary from user to user because of the variable leak 19 . FIG. 5 illustrates the inter-user variability in Y(ω) for 5 different users of an exemplary handset. Because of this variability, the optimal fixed feed-forward filter W FFOPT (ω) for one individual's ear will not be the correct optimal filter for another individual's ear, and for such second individual, noise-cancellation performance will be degraded.
In co-pending patent application Ser. No. 09/055,481, cited above, there is described an electro-acoustic module, for mounting receiver 5 , that is adapted to substantially reduce the inter-user variability in transfer functions Y(ω) and F(ω). In such an electro-acoustic module, a small fixed leak is introduced in parallel with the variable leak, 19 . In effect, the fixed leak “shorts out” the variable leak, thus making the total leak appear almost constant. The reduced variability in Y(ω) for the same five users of FIG. 5 is shown in FIG. 6 .
Although this result contributes significantly to the effectiveness of fixed feed-forward noise cancellation designs, it fails to provide the correct optimal fixed filter, W FFOPT (ω), that should be used for a broad range of users.
A practical such filter W FFOPT (ω), for a broad range of users, is advantageously obtained by minimizing the residual pressure given by equation 3 over a range of users. The result gives an optimal averaged fixed feed-forward filter, <W FFOPT (ω)>, according to:
< W FFOPT (ω)>=< F (ω)>/< Y (ω)>, (4)
where the angular brackets indicate an average over several users.
In principle, the optimal feed-forward filter may be implemented by Fourier transforming W FFOPT (ω), as given by equation (3), into the time domain and then embodying the result in software as a digital finite-duration impulse response (FIR) filter. A theoretical understanding of such a procedure may be obtained, e.g., from the above-cited book by Nelson and Elliot at pages 180–181.
Alternatively, direct time-domain methods, such as the filtered-x LMS algorithm (described, e.g., in the above-cited book at page 196) can be used to derive the coefficients of the optimal fixed feed-forward FIR filter to minimize the residual pressure, ε.
In both cases, however, if the number of FIR filter coefficients is large, then the computational load on the DSP may be unacceptably large. Furthermore, there is a need in both cases to ensure that the optimal fixed feed-forward FIR filter does not significantly amplify the ambient noise outside of the frequency range of design. Still further, when these conventional techniques are used, there is no way to specify, a priori, the level of noise cancellation performance, even in an average sense.
We have discovered that these disadvantages can be overcome by implementing our feed-forward filter design in an infinite-duration impulse response (IIR) filter, and not in a FIR filter.
Those skilled in the art will appreciate that both FIR filters and IIR filters are defined by sets of filter coefficients. Well-known algorithms, such as the least mean square (LMS) algorithms, are available for setting the values of these coefficients to achieve some desired performance. (In the case of LMS algorithms, the coefficients are adjusted so as to minimize an error function such as the squared modulus of the residual noise, integrated over a frequency range.)
The mathematical description of a FIR filter is related in a directly intuitive way to a delay line having weighted taps, and a summing element for combining the tapped outputs in accordance with their respective weights, given by the filter coefficients. As a general rule, the coefficients of such a system are readily determined using standard algorithms.
The mathematical description of an IIR filter is most concisely expressed by the system function of the filter. The system function is a complex-valued function of a complex value. The system function is defined by the locations of its poles and zeroes in the complex plane. The filter coefficients are related to these poles and zeroes. As a general rule, the coefficients of an IIR filter are more difficult to determine using standard algorithms, relative to FIR filter coefficients. However, if an IIR filter is achievable, it can often perform using substantially fewer coefficients, and with substantially greater computational efficiency, than a comparably performing FIR filter.
In fact, we could not directly implement our optimal fixed filter, W FFOPT (ω), in an IIR filter. Because of the erratic behavior of F(ω) above 1 kHz, and especially above 2 kHz, W FFOPT (ω) would be too poorly defined to provide a stable filter even up to 1 kHz. Moreover, direct implementation of this function could call for the filter to operate non-causally, which is not achievable. Significantly, our attempts at direct implementation using standard algorithms failed to converge within reasonable lengths of time.
We overcame these problems by finding an appropriate weighting function, and multiplying W FFOPT (ω) by this weighting function to obtain a new feed-forward filter function {tilde over (W)} FF (ω). The weighting function is designed to roll off at high frequencies, such as frequencies above 1 kHz. As a result, the erratic, high-frequency portion of so the bad part of F(ω) may be set to a well-behaved proxy such as a constant, unit-valued function. Moreover, we found that {tilde over (W)} FF (ω) can be made to closely approximate W FFOPT (ω) at frequencies up to 1 kHz, or even up to 2 kHz. When an LMS algorithm was used to implement {tilde over (W)} FF (ω) in an IIR filter, we found that the solution converged readily.
The weighting function is defined in terms of the solution to the feedback noise cancellation problem for the same telephonic handset. Let W FB (ω) be the transfer function of the negative feedback filter that solves this problem. Let Y(ω), as before, be the transfer function of the receiver. Then G(ω)=Y(ω)W FB (ω) is the open loop gain of the feedback noise cancellation system. Our weighting function is
G ( ω ) 1 + G ( ω ) .
Thus,
W ~ FF ( ω ) = G ( ω ) 1 + G ( ω ) W FF OPT ( ω ) .
As explained above, W FFOPT (ω) is based on averaged values of F(ω) and Y(ω). This is particularly advantageous because the averaged values define the center of an operating range for the positioning of the handset when it is in use. This maximizes the likelihood that a given user will find a personal optimum position for the handset when using it.
Those skilled in the art will appreciate that there is some flexibility in solving the feedback noise cancellation problem. Thus, it will generally be the case that an open loop gain G(ω) can be devised that not only provides a feasible solution to the feedback problem, but also tends to be relatively large at speech-band frequencies below 1 or 2 kHz, and tends to roll off above 1 or 2 kHz. Such an open loop gain will provide a weighting function for the feed-forward system that is near unity in the frequency range of interest, and rolls off above that range.
We now provide details of our new algorithmic approach, in which a weighted, feed-forward transfer function is implemented in an IIR filter.
In this regard, reference is usefully made to the classic negative feedback noise cancellation system of FIG. 1 . In such a system, the residual pressure ε in the ear is well known to be given by:
= n 2 /[1 +Y (ω) W FB (ω)]= n 2 /[1 +G (ω)] (5)
where G(ω)=Y(ω)W FB (ω) is the open loop gain, and W FB (ω) is the negative feedback filter, which is to be designed to stably minimize the residual pressure given by equation (5).
Equation (5) may be recast into the following form:
ε= n 2 −G (ω)ε. (6)
Substituting equation (5) into the right hand side of equation (6) yields:
ε= n 2 −n 2 G (ω)/[1 +G (ω)] (7)
Reference is made to feed-forward behavior by here introducing the transfer function F(ω) which, as explained earlier, relates the noise acoustic pressure n 2 to the noise acoustic pressure n 1 . This permits equation (7) to be rewritten in the following form, which reveals a feed-forward structure:
ε= n 2 −{F (ω) G (ω)/[1 +G (ε)]} n 1 . (8)
Comparison of equation (8) with equation (1) (i.e., ε=n 2 −Y(ω)W FF (ω)n 1 ) reveals that the fixed feed-forward filter {tilde over (W)} FF (ω) for a fixed feed-forward noise canceling system may be obtained from the open loop gain G(ω) of a feedback noise cancellation system, the noise transfer function F(ω), and the receiver transfer function Y(ω). That is:
{tilde over (W)} FF (ω)=[F(ω)/Y(ω)]{G(ω)/[1+G(ω)]}. (9)
Significantly, the expression for {tilde over (W)} FF (ω) in equation (9) consists of two factors, F(ω)/Y(ω) and G(ω)/[1+G(ω)]. As G(ω) becomes very large, {tilde over (W)} FF (ω) approaches W FFOPT (ω)=F(ω)/Y(ω), the optimal fixed feed-forward filter required to reduce the residual pressure in a user's ear. Consequently, the optimal fixed feed-forward filter for a given frequency band is easily realized using classical feedback design techniques in which G(ω) is made as large as possible over the desired frequency band, and then rolled off in magnitude outside of that frequency band to ensure stability. As noted, the ratio of user averaged values, <F(ω)>/<Y(ω)>, is advantageously used in equation (9).
An alternate interpretation of equation (9) is that the product of F(ω) and the weighting function is a modified transfer function that has improved high-frequency behavior.
Significantly, our methodology for designing a feed-forward filter permits the level of noise-cancellation performance to be specified a priori. (In this regard, it is quite different from conventional methodologies for feed-forward filter design. This is evident from equation (5), in which it is seen that the noise cancellation performance can be specified by specifying G(ω), consistent with stability. Since equation (5) led directly to equation (8), the achievable feed-forward noise cancellation, it is clear that the proposed technique allows the designer a means of specifying, a priori, the desired level of fixed feed-forward noise cancellation performance. It should also be noted that once G(ω) has been devised, there will be no inter-user variability in G(ω), and therefore there will be no chance of instability.
EXAMPLE
We made a fixed feed-forward noise cancellation system, incorporating the physical and algorithmic design principles described above. We tested our new system on a range of users. The average noise cancellation performance and standard deviation for the tested user group are shown in FIG. 7 . As is evident from the figure, our system produces a peak average noise cancellation of close to 15 dB in the users' ears, with a standard deviation of about +3 dB.
In further tests, we found that when a far-end speech signal is also present, the users tend to position the earpiece of the handset in a way that tends to maximize the ratio of the far-end speech signal to the remaining noise. As mentioned above, this behavior bears some analogy to the tuning of a radio dial to maximize the signal-to-noise ratio out of the loudspeaker. In effect, by adjusting the position of the earpiece against his ear, a user is adjusting the ratio F(ω)/Y(ω) for his ear such that it is as close as possible to the optimal result for cancellation given by equation (4). | A telephonic handset comprises an active noise reduction (ANR) system. The ANR system comprises a reference microphone and an IIR filter. The IIR filter is receivingly coupled to the reference microphone with respect to noise reference signals, and it is transmittingly coupled to the receiver transducing element of the handset. The ANR system is configured as a fixed feed-forward noise cancellation system. Preferably, the IIR filter has a transfer function derived, in part, from the open-loop gain of a feedback noise cancellation system.
In specific embodiments of the invention, the noise reference microphone is situated so as to sample the ambient noise field near the front face of the receiver, but without directly sampling the noise field on the front face. | 6 |
STATEMENT OF GOVERNMENT INTEREST
The research that led to the development of the present invention was sponsored by the National Oceanic and Atmospheric Administration's (NOAA's) National Marine Fisheries Service (NMFS). NOAA is a part of the U.S. Department of Commerce, a component of the U.S. Federal government. The United States Government has certain rights in this invention.
FIELD OF THE INVENTION
The present invention relates to fish feeder. In particular, the present invention is directed toward a microparticulate feeder for larval and juvenile fishes.
BACKGROUND OF THE INVENTION
Microparticulate diets for larval and small juvenile fish pose specific challenges for aquaculturists. Microparticulate diets, by definition, have a very high specific surface area, making them vulnerable to the effects of oxidation and hydration. Many of the diet components are often labile and hygroscopic, which further exacerbates the problem. Fine, hygroscopic particles tend to clump and cake together, and adhere to surfaces with which they come in contact, making rationing and delivery difficult to achieve by automation. See, e.g., Michael B. Rust, “The Challenges of Feeding Microparticulate Diets to Larval Fish”, The Advocate, February 2000, pages 19-20, and Juan P. Law, et al, “Co-feeding microparticulate diets with algae: toward eliminating the need for zooplankton at first feeding in larval red drum”, Aquaculture, 188, (2000) pages 339-351, both of which are incorporated herein by reference.
The digestive system of larval fish is slow to develop; so artificial diets fed to them must have a high leaching rate in order to make nutrients available to the larvae that ingest the diets. This high leaching rate is a two-edged sword, in that upon contact with the water, nutrients are often lost to solution before the larvae can ingest them. Larval fish also have no body energy reserves to call upon and so they require a constant stream of available nutritive feed. To circumvent this problem, culturists often employ a technique called, “feeding the water”, where feed is delivered in pulses to excess. The feed is either eaten, falls to the bottom of the tank, or is cleared by the exchange of circulating water in the tank. This technique unfortunately creates an alternating feast and famine situation that is conducive to neither good nutrition nor good hygiene.
Small juvenile fish have a digestive system and some reserves, however they still require frequent feeding, and accurate rations. Feeding early juvenile fish can be prohibitively expensive in terms of husbandry labor. Most of this labor is rationing and feeding. Accuracy of ration is paramount in diet trials, where growth and feed conversion are correlated to the diet actually consumed by the fish; therefore feeding the water will not work. An accurate ration is calculated based upon what the fish can be expected to eat in one feeding, and must be precisely delivered for a diet trial experiment to succeed.
Prior Art automated fish feeders can be categorized by a few basic groups:
Belt feeders, generally employ a slow moving, spring wound clock powered, conveyor belt that dumps the feed off the belt as it is rolled up over the tank. An example of such a feeder is the Ziegler Belt Feeder, manufactured by Zeigler Bros., Inc. of Gardners, Pa. See, e.g., Ziegler Belt Feeders brochure (Zeigler Bros., Inc., Gardners, Pa.) Sep. 4, 2009, incorporated herein by reference Drum feeders employ a rotating drum filled with feed and capture a small aliquot for feeding and dispenses it with each rotation. An electric clock motor usually powers this type of feeder. An example of such a feeder is the Lifegard Aquatics Intellifeed Aquarium Fish Feeder, made by Lifegard Aquatics of Cerritos, Calif. See, e.g., Intellifeed Aquarium Fish Feeder operating instructions, (Lifegard Aquatics, Cerritos, Calif.), incorporated herein by reference. Shear feeders use some method of sliding the feed off of a base and over an edge to drop into the fish tank. This type of feeder also includes screw feeders and dial feeders, which have individual rations in separate chambers, arranged radially on a disk. The disk rotates, powered by a synchronous AC clock motor and the feed drops as it is slid over a hole in the base. An example of a screw-type feeder is the Eheim 3582 Automatic Feeder by EHEIM GmbH & Co. KG of Deizisau, Germany. An example of a dial-type feeder is the Fish Mate F14 by Ani Mate Inc., of Conroe, Tex. See, e.g., EHEIM 3582 Automatic Feeder User Manual (EHEIM GmbH & Co. KG of Deizisau, Germany), January 2008 and Fish Mate F 14 Instructions (Ani Mate Inc., Conroe, Tex.), both of which are incorporated herein by reference. Vibrating feeders use a hopper with a narrow annular opening, allowing the feed to drop when the unit is vibrated. An example of a vibratory feeder is the Sweeney Model AF6 Vibratory Feeder by Sweeney Feeders of Boerne Tex. See, e.g., Sweeney Aquaculture Feeders brochure (Sweeney Feeders, Boerne Tex.), incorporated herein by reference.
There are a number of Prior Art Patents relating to various fish feeders. The following is a summary of a number of those Prior Art Patents.
Belloma, U.S. Pat. No. 6,715,442, issued Apr. 6, 2004, and incorporated herein by reference, discloses a fish feeder having inner and outer trays, which move relative to one another, to dispense fish feed using gravity. Belloma discloses using a pneumatic actuator to power the device.
Patterson, et al., U.S. Pat. No. 6,571,736, issued Jun. 3, 2003, and incorporated herein by reference, discloses a fish feeder for use with moist fish feed. The moist feed disclosed are pellets, of the type used with fish farming. A blower is used to direct the fish pellets towards a fish pen through a nozzle attached to the device.
Lin, U.S. Pat. No. 6,192,830, issued Feb. 27, 2001, and incorporated herein by reference, discloses an underwater fish feeder than uses compressed air. Compressed air is used to eject fish feed from a remote fish feed holder.
Halford, U.S. Pat. No. 6,082,299, issued Jun. 4, 2000, and incorporated herein by reference, discloses an automatic fish feeder using a screw-type mechanism to eject fish feed from a hopper, which then falls into the fish tank.
Evans et al., U.S. Pat. No. 5,709,166, issued Jan. 20, 1998, and incorporated herein by reference, discloses a refrigerated automatic fish feeder.
Flahs, II, U.S. Pat. No. 5,353,745, issued Oct. 11, 1994, and incorporated herein by reference, discloses an Aquaculture system and methods for using same. A feeding hopper (FIG. 5) is used to gravity feed the diet to the tank. A gas ejector 110 is used to spread the feed over the surface.
Masopust, U.S. Pat. No. 5,199,381, issued Apr. 6, 1993, and incorporated herein by reference, discloses an automatic fish feeder using a rotating disc.
Newton et al., U.S. Pat. No. 5,072,695, issued Dec. 17, 1991, and incorporated herein by reference, discloses an automatic fish feeder using a rotating wheel.
Smelzer, U.S. Pat. No. 4,628,864, issued Dec. 16, 1986, and incorporated herein by reference, discloses an automatic fish feeder, which is water-driven. A water-filled container drives a rotating arm.
Olsen et al., U.S. Pat. No. 4,429,660, issued Feb. 7, 1984, and incorporated herein by reference, discloses a Water Powered Fish Feeder. As with Smelzer, water drives a lever arm to dispense fish feed.
Molinar, U.S. Pat. No. 4,399,588, issued Aug. 23, 1983, and incorporated herein by reference, discloses an automatic fish feeder and orienter. This device actually orients individual fishes for feeding.
Suchowski, U.S. Pat. No. 4,089,299, issued May 16, 1978, and incorporated herein by reference, discloses an air-operated fish feeder. This device, which is immersed in a fish tank, is operated by air pressure, apparently from an aquarium pump.
Hoday et al., U.S. Pat. No. 3,738,328, issued Jun. 12, 1973, and incorporated herein by reference, discloses a Fish Feeder for an aquarium, which is driven by a clock motor.
Sanders, U.S. Pat. No. 3,717,125, issued Feb. 20, 1973, and incorporated herein by reference, discloses an automatic feeder for a fish aquarium. A piston slides a rod, which takes feed from a hopper and passes it to the aquarium once a day.
Cook, U.S. Pat. No. 3,231,314, issued Jan. 25, 1966, and incorporated herein by reference, discloses an automatic fish feeder using a blower motor for dispensing palletized fish feed to a fish tank. A hopper dispenses fish feed to two fish tanks ( FIG. 5 ) via two parallel discharge ducts 4 (Col. 3, lines 12-41). A reciprocating metering plate dispenses fish feed from the hopper. A blower is used to force the feed to two tanks at the same time, and to dry the ducts.
Appleton, U.S. Pat. No. 3,050,029, issued Aug. 21, 1962, and incorporated herein by reference, discloses an automatic fish feeder of the disc variety.
Smolin, U.S. Pat. No. 2,785,831, issued May 28, 1953, and incorporated herein by reference, discloses an automatic fish feeder with a rotating shaft, which dispenses a measured amount from a hopper, via gravity feed.
The Arvotec T Drum 2000 Feeder (see. e.g., Arvotec, Feeding Technology for Modern Aquaculture brochure Huutokosken Arovkala Group, Huutokoski, Finland, and Arvotec Feeder and Spreader Manual , Arvotec, Huutokoski, Finland, and Arvotec, Feeding Technology brochure, Huutokosken Arovkala Group, Huutokoski, Finland, all of which are incorporated herein by reference) discloses a hopper-type feeder with a compressed air dispersal unit. Compressed air is used to blow the feed from a chute, onto the surface of a fish tank. Note the dosing drum designs (Page 9, of the Feeding Technology Manual) and the nature of the compressed air dispersal unit (Page 9 of the Feeder and Spreader manual).
The Arvotec Feeding Technology manual also discloses the use of a centralized pipe feeding system, with a manifold and a number of pipes to feed different tanks. Each manifold may feed up to four tanks, and up to 28 tanks may be fed. It appears each manifold has a switching device to direct feed to a different tank, via a 3″ open-ended pipe. However, as with the Cook reference, this embodiment uses a blower to blow feed through large (3″) open pipes. The problem with such a design, as with Cook, the open-ended pipes above fish tanks, may harbor moisture, making such a design unsuitable, particularly for microparticulate feeds, which may cake and clog in the piping. The brochure states that the number of pipes is reduced, which makes cleaning easier. However, this seems to be an admission that runs of piping with fish feed and moisture contamination could require frequent cleaning. Moist caked-on fish feed in such pipes would be an ideal environment for the growth of bacteria, fungus, and mildew, which could in turn sicken or kill the fish or larva being fed.
To avoid this problem, Arvotec shows another “robotic” embodiment, where one or more hopper-type feeders are mounted on a monorail, which in turn is moved over a plurality of tanks to distribute the feed. The problem with this design is that the hoppers need to be refilled over time. To solve this problem, in another embodiment, long hoses are used to refill the hoppers from even larger hoppers. However, such a design results in a large number of expensive components, hoppers, blowers, hoses, and the like, adding to cost and complexity. Moreover, the hoses need to be made flexible enough to avoid interfering with the operation of the monorail. The robotic solution is rather costly and over-designed.
In another embodiment, the Arvotec Feeder shows a rotating drum feeder, where the drum rotates to measure a portion of feed (determined by cutout sizes in the drum) and when rotating, dumps these onto a dispersal plate. Compressed air is used to spray the feed over the surface of the water. In one embodiment, which is illustrated on a YouTube video, compressed air is used to disperse the fish feed pellets. From the video, as well as the product catalogs, it appears that the feeder merely dumps feed onto a plate, which in turn uses a timed charge of compressed air to spray onto the surface of a fish tank. In another embodiment, a rotary (spinner-type) spreader is used. The feeder in that embodiment is mounted above the tank, and thus does not solve the problem of moisture contaminating the fish feed.
The most common shortcoming of all these prior feeders is that they don't protect the feed from the effects of moisture and oxygen. Since most feeders dispense the feed directly above the fish tank, they subject the feed to a highly humid environment. The hygroscopic nature of larvae feeds results in feed eventually caking and accumulating on the feeder surfaces, resulting in deterioration of both the feed quality, and the accuracy and precision of the dispensed ration.
The challenge then, is to create a feeder that can repeatedly and automatically deliver a small, precise amount of a fragile and functionally difficult material, and protect the feed from the environment when not in use. It remains a requirement in the art to provide a feeder which may be used to feed multiple tanks, without the need for large tubes, as well as avoiding moisture and caking in such tubes, which would as a result, require frequent cleaning. And it remains a requirement in the art to provide such a feeder in a simple and straightforward manner that minimizes the number of components, cost, and complexity of the device.
SUMMARY OF THE INVENTION
The present invention improves upon the Prior Art by overcoming the environmental challenges that lead to inconstant rationing and reduced feed quality associated with other feeders. By separating the dosing dispenser from the terminal delivery, the feed can be protected from the humid environment above the fish tank. A sealed rotating chamber further protects the feed in the hopper from moisture and oxygen between feedings. In addition to conveying the feed, the gas dries both the feed and the tubing and terminal valve during feeding. Thus the system avoids accumulation of feed on surfaces exposed to the atmosphere.
The small (ca. 15 mg) precisely sized portion dispensed by the feeder of the present invention affords a greater control of the feeding schedule so that fish can be fed evenly over time or, for growth trials, to a precise ration. In recent tests, the feeder of the present invention was used to compare repeated accumulations of feed from ten cycles of the rotating chamber. The feed was trapped by a mineral oil bath in a tared beaker. After five repetitions, the standard deviation is generally 3% of the mean accumulated weight. In tests of the manifold system, a standard deviation of 5% of the mean was achieved after 200 rations delivered to each of two terminal valves, ten cycles each at 15 min. intervals, over five hours. The test feedings were initially spread out over five hours to relieve the duty cycle of the controlling solenoids, ensuring that they did not overheat. Subsequent testing has shown this to be unnecessary, and tests are now conducted at five-minute intervals.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation view of dispenser components of microparticulate feeder.
FIG. 2 is cross-section of dispenser component in the load position.
FIG. 3 is cross-section of dispenser component in the discharge position.
FIG. 4 is a schematic of pneumatic controls and conveyance components of the microparticulate feeder system.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an elevation view of dispenser components of microparticulate feeder. Note that the depicted design uses ‘O’ rings 190 as both seals and bearings. In an alternative embodiment, captive ball bearings and cup seals may be used to ensure long-term performance over a heavy-duty cycle.
Referring to FIG. 1 , the feeder of the present invention uses a manifold delivery system (as shown in FIG. 4 ) attached to a central dispensing unit 100 . Thus, one feeder can feed several fish tanks. The feeder 100 dispenses a discrete volume of feed 105 , determined by a chamber 150 in a rotating shaft 170 , rotating within housing 160 . The feed 105 is loaded into the chamber 170 by gravity from a sealed hopper 140 above the chamber 150 . A small vibrator 130 , attached to the hopper 140 , aids in settling the feed into the chamber. Vibrator 140 may comprise a cell phone type vibrator commonly known in the cell phone art. The chamber 150 includes an L-shaped airway radially situated through the shaft 170 . Shaft 170 is supported by O-rings 190 , which act as bearings. The chamber is isolated by the O-rings 190 , which also act as seals.
The shaft 170 is rotated back and forth through an 180° arc via a pneumatic actuator 115 such as the Parker PRNA20S-180-905 pneumatic actuator made by Parker-Kuroda of Chiba, Japan. See, e.g., Miniature HI - ROTOR/Standard type PRNseries product specification sheets, (Parker-Kuroda, Chiba, Japan) incorporated herein by reference. Actuator 115 may be coupled to shaft 170 by setscrews 110 . The actuator 115 , shaft 170 and feed hopper 140 may all be supported by a PVC housing 160 . In one embodiment, the dispenser housing 160 is machined from one piece of solid PVC. Shaft 170 may be made of polyacetal resin and be approximately ¾″ in diameter to match the inner diameter of housing 160 . Epoxy potting 120 may be used to ensure an interference fit against the shaft 170 at the loading port of the housing 160 .
Rotary actuator 115 may be coupled to a pressurized gas source via connectors 111 , which may comprise push-to-connect 5/32″ tubing fittings. As will be discussed in more detail below in connection with FIG. 4 , pressure to rotary actuator may be controlled electronically, via solenoid valves, to time the system to dispense feed to individual feeders, using a pre-programmed controller.
LED 210 may be used to indicate to the user that the vibrator has been activated. Most hatchery environs are too noisy to hear the vibrator being actuated, and LED 210 provides a visual indication in such a noisy environment. In addition, if multiple feeders are used, as in the case of a diet study where multiple diets are being tested against one another, then LEDs of different colors distinguish which feeder is being deployed.
A small one-way vent valve 135 such as the CVT-18VL check valve, made by Industrial Specialties Mfg. & IS Med Specialties of Englewood, Colo. (see. e.g., the Specialties Mfg. & IS Med Specialties CVT-18VL spec sheet, incorporated herein by reference) may be attached near the top of the hopper, next to the LED. Its function is to vent any excess pressure from gas that blows into the hopper. Typically, this occurs when the shaft is rotated into the load position, thus venting the previously pressurized manifold. The gas passes upwards through the feed, keeping it loose and desiccated.
FIG. 2 is cross-section of dispenser component in the load position. FIG. 3 is cross-section of dispenser component in the discharge position. Referring to FIG. 2 , when in the “load” position, chamber 150 is positioned under the hopper 140 , and the L-shaped airway portion is sealed against the housing 160 . Feed falls from the hopper, aided by vibrator 130 , into the chamber 150 . In the “discharge” position, as shown in FIG. 3 , the chamber 150 is positioned above the exit port 200 , and the L-shaped airway is connected to the carrier gas port 220 . Dry compressed air or other gas (e.g., nitrogen or the like) then pushes the portioned feed out through exit port 200 .
As illustrated in FIG. 4 , the exit port 200 is connected via a distribution manifold 410 and tubing 420 to one or more terminal valves RV, located at one or more fish tanks. Distribution manifold 410 may comprise a plurality of Y-type tubing manifolds, connected in series, in order to provide the desired number of outlets. A number of different manifold designs were tried, and the common tube style was rejected, as feed hangs up in it, and then breaks off to dispense randomly. Thus, the multiple-Y design as shown as element 410 in FIG. 4 is used, and it works quite well with, no hang up.
The terminal valves RV may comprise a pneumatically operated pinch valve such as the RedValve™ 2600, manufactured by Red Valve Company, Inc. of Carnegie, Pa., that seals the tubing 420 when not in use. See, e.g., RedValve™ Series 2600 product brochure, (Red Valve Company, Inc., Carnegie, Pa.), incorporated herein by reference. The actuator 115 and terminal valves 420 are pneumatically controlled via computer driven solenoids S 3 ( 430 , 440 ), while the carrier gas supply is controlled via solenoid valve S, as illustrated in FIG. 4 .
In one embodiment, corresponding colored polyethylene tubing may be used for the manifold and dispenser tubing, to make it easier to know which tanks are being fed. Separate manifolds may be required to avoid cross contamination of test diets; in general feeding, this would not be necessary. A second LED in the solenoid activation circuit may also indicate which solenoid is activated, and which corresponding tank is being fed.
FIG. 4 is a schematic of pneumatic controls and tuning components of the microparticulate feeder system of the present invention. A gas supply 405 is fed to a dessicator D, to remove any excess water. Compressed air may be used, utilizing a small portable air compressor, or other supply of compressed air, suitably regulated, from an industrial source. Dessicator D may be used to remove any excess water from the air supply. As noted previously, microparticulate feeds may be sensitive to moisture. Thus, to prevent caking and clogging, a supply of dry gas may be required. As an alternative to compressed air, other gases, such as nitrogen may be used, having the additional advantage of reducing oxidation of feed in the supply tubing 420 .
Output of dessicator D is fed to regulator R, which may be provided with gauge G, so that pressure may be adjusted to appropriate levels as previously discussed. Gas pressure used is typically between 3-5 psi static, and 1-2 psi dynamic. Flowmeter F measures flow of gas (generally 5-10 Lpm), for use in dispensing microparticulate feed. Solenoid valve S may be activated to pass this lower-pressure gas to port 220 of dispenser 100 , to force the metered portion of microparticulate feed through manifold 410 , though tubing 420 , and out of an opened one of a plurality of terminal valves RV. For the purposes of this application, the terms “carrier gas” is used to describe the dried, lower-pressure gas used to force the microparticulate feed though the system. The term “actuator gas” is used herein to describe the higher-pressure gas used to activate terminal valves and the actuator.
The use of dried compressed air (or other gases) represents an improvement over Prior Art devices, which attempt to use blowers and the like to blow feed to multiple fish tanks. Blowers, using atmospheric air, do not provide a means for drying the air, and thus may result in caking and clogging if microparticulate feed is used. For that reason, Prior Art systems using blowers and the like are generally limited to pellitized feed, which is less likely to cake or clog due to moisture.
Gas supply 405 may also be used for actuator gas to control terminal valves RV. As the actuator gas used to control actuator 115 of dispenser 100 , as well as terminal valves RV is not in contact with the microparticulate feed, higher-pressure compressed air may be used for this purpose. Hence, as illustrated in FIG. 4 , the actuator gas supply is connected directly to three-way solenoid valves S 3 and actuator 115 of dispenser 100 , without passing through dessicator D, regulator R, or flowmeter F. The actuator gas may be in the range of substantially 30-50 psi, as needed to actuate the components of the present invention.
The actuator gas is used to activate these components, as it reduces the risk of electrocution, both to workers in the facility, and to the fish. Having fish feeding devices with electrical components, hanging over fish tanks or ponds—or in near proximity thereof—creates a risk that power leads may come in contact with water, electrocuting and injuring or killing the fish, or a worker in the hatchery or fish farm. Thus, the present invention utilizes compressed actuator gas such as compressed dried air, to reduce this hazard. In addition, electrical components may be more susceptible to corrosion and shorting, and thus may be less reliable in a marine or aqueous environment.
As illustrated in FIG. 4 , the timing of the entire device (feeding timing and frequency, correct stepping of the dispensing unit, and distribution, via manifold and terminal valve sequencing) may be controlled via a laptop computer 450 (e.g., Macintosh or the like) running Indigo™ home automation software available from Perceptive Automation of Allen, Tex. One or more control modules 460 may be coupled to laptop computer 450 to convert signals from laptop computer 450 into electrical control signals to actuate solenoid valves S and S 3 ( 430 , 440 ). Such control modules may comprise a Z-Wave, INSTEON, or X10 control module, as is known in the art, for use with Indigo software.
Conceivably, any precision timing program may operate the unit. A user may already possess specific feeding program software, which may be modified to operate the apparatus of the present invention. Such timing devices and automation software are known in the art and are not described in detail herein.
When the timing program determines that it is time to feed a particular tank of fish, the timing software activates three-way solenoid valves S 3 430 , 435 to supply and vent gas to actuator 115 of dispenser 100 . Both three-way solenoid valves S 3 430 , 435 are activated to rotate the actuator. Solenoid valve 430 goes from normally closed (vent), to open, while solenoid valve 435 goes from normally open, to closed (vent). Both solenoids 430 , 435 are used to operate the actuator; one to drive it one direction; one to drive it back. In each direction, one of solenoid valves 430 , 435 is not driving, it is venting. Actuator 115 then rotates shaft 170 into the load position as illustrated in FIG. 2 , and feed drops into chamber 150 . Vibrator 210 may turn on and off while the chamber 150 is in the load position. Solenoids S 3 430 435 are then reversed, and actuator 115 rotates shaft 170 into discharge position as illustrated in FIG. 3 . Solenoid S is then actuated, passing dried, lower-pressure carrier gas through dispenser 100 via carrier gas port 220 and out through exit port 200 , blowing the dispensed feed with it.
At the same time (or a similar time) when solenoid S is activated, one or more (in the preferred embodiment, one) of three-way solenoid valve S 3 440 is activated, to vent compressed actuator gas in order to open one of the terminal valves RV. All unused terminal valves are in the pressurized state, and the three-way valve S 3 allows the line to vent when activated. As only one of the terminal valves RV is open at any given time, the feed being blown through dispensing unit 100 passes through the corresponding tubing 420 from manifold 410 , and onto the surface of the water of the fish tank or pond. As dry compressed air (or other gases) are being used to as carrier gas to disperse the microparticulate feed, the feed does not cake or clog, and moreover is less likely to oxidize or spoil.
Rather than use a switching manifold to deliver feed (as in the Arvotec device described in the Background of the Invention), the present invention controls the path the microparticulate feed takes by pneumatically opening a corresponding terminal valve, RV. Since the carrier gas follows the path to the open valve, the microparticulate feed is transferred to the correct tank. This approach has a number of advantages over the Prior Art. A switching manifold mechanism would tend to clog and cake with fish feed after a time, which would then require frequent cleaning in order to work properly. In contrast, in the present invention, a contiguous manifold is used, with no switching or directing mechanism, and thus no mechanism to clog. Since a dry compressed carrier gas is used in the manifold 410 and tubing 420 , the microparticulate feed will not cake or clog, but instead be transmitted to the desired tank. Even if some small amount of feed particles remain in the manifold 410 or tubing 420 , the dry, sealed, compressed gas environment prevents the feed from clogging or caking. In contrast, the Arvotec system, using open-ended tubes and a blower (sending undried atmospheric air) would require periodic cleanings to prevent clogging, as mentioned in their literature. The use of a four-way switching manifold in that design adds unnecessary complexity and cost to the design.
In the present invention, control of quantity and timing of feeding can be readily programmed, using control software as previously described. Using different shaft elements 170 , which provide different chamber sizes 150 , may control the quantity of feed dispensed. However, it may be easier, if additional feed quantities are required, to instead provide multiple feedings using a single chamber size 150. Thus, for example, in the preferred embodiment, a 15 mg chamber 150 is provided, which is suitable for test feeding smaller tanks. If it is desired to provide 30, 45, or 60 mg of feed, the device may be simply actuated two, three, or four times (or more) in sequence, to provide the quantity of feed required.
Similarly, the timing of feeding may be altered and programmed at will, to provide feedings at different times during the day, once a day, or whatever requirements are needed for a particular fish or larva feeding program. A number of different tanks may be fed using one dispenser 100 , by using a plurality of terminal valves RV, one for each tank. For larger tanks, multiple valves RV may be used, which may be activated individually, or in concert, if desired. The device may also be used to feed a single tank. While illustrated in FIG. 4 as feeding four tanks, other numbers of terminal valves RV and associated solenoids S 3 440 may be used without departing from the spirit and scope of the present invention.
By timing the operation of the vibrator, the terminal valve, the pneumatic actuator, and the carrier gas, the feeder is loaded, locked, discharged and the feed is conveyed to the water's surface in the fish tank. When not in use, the feed in the hopper is sealed and protected from moisture and ambient oxygen. An option is available to introduce dry nitrogen as a purge gas to the tubing, chamber and hopper at the end of each cycle to ensure a dry and inert atmosphere, if desired.
What distinguishes the feeder of the present invention from others is the ability to overcome the environmental challenges that lead to inconstant rationing and reduced feed quality associated with other feeders. By separating the dosing dispenser from the terminal delivery, the feed can be protected from the humid environment above the fish tank. The sealed rotating chamber further protects the feed in the hopper from moisture and oxygen between feedings. In addition to conveying the feed, the carrier gas dries both the feed and the tubing and terminal valve during feeding. Thus the system avoids accumulation of feed on surfaces exposed to the atmosphere.
The small (ca. 15 mg) precisely sized portion dispensed by the feeder of the present invention affords a greater control of the feeding schedule so that fish can be fed evenly over time or, for growth trials, to a precise ration. In recent tests, the feeder of the present invention was used to compare repeated accumulations of feed from ten cycles of the rotating chamber. The feed was trapped by a mineral oil bath in a tared beaker. After five repetitions, the standard deviation is generally 3% of the mean accumulated weight. In tests of the manifold system, an average standard deviation of 5% of the mean was achieved after 200 rations delivered to each of two terminal valves, ten cycles each at 15 min. intervals, over five hours. The test feedings were initially spread out over five hours to relieve the duty cycle of the controlling solenoids, ensuring that they did not overheat. Subsequent testing has shown this to be unnecessary, and tests are now conducted at five-minute intervals.
Although described above in terms of the preferred embodiment at the time of filing of the present application, the present invention may also be modified to improve durability and precision. Such modifications, within the spirit and scope of the present invention include:
The incorporation of captive ball bearings and cup seals on the rotating shaft, to ensure long term performance over a heavy duty cycle. Improvements to the design of the manifold system to improve the precision between repeated feedings and between feedings dispensed from individual terminal valves. An optional dry nitrogen injection between feedings, to ensure a dry, inert atmosphere within the tubing, and the dispensing unit.
There are also a number of potential applications for the apparatus of the present invention. The primary embodiment of the feeder is as a laboratory tool where small batches of fish are reared for experimental purposes. The feeder may also be used in small production hatcheries, such as exotic fishes for the aquarium trade. A scaled-up version for delivery of larger volumes of feed may be used by most commercial aquaculture facilities. While disclosed in the context of microparticulate feeds, the present invention may be adapted for other types of feeds (small pellitized feeds and the like) by suitably modifying piping sizes and the like. In addition, the feeder of the present invention may also be used to feed other types of animals or to distribute other types of particulates.
While the preferred embodiment and various alternative embodiments of the invention have been disclosed and described in detail herein, it may be apparent to those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope thereof. | A feeder for larval and juvenile fishes is capable of delivering a small (ca. 15 mg) precise dose of microparticulate (ca. 100 μm diameter) feed to selected locations, via pneumatic conveyance and control. A source of low-pressure dry gas is used to blow microparticulate feed through a manifold and into a selected one of a number of tubes. A terminal valve at the end of the tube is selectively activated to send the feed to a selected tank or pond. When not in use, the feeder is sealed, and the feed protected from moisture and ambient oxygen. | 8 |
FIELD OF THE INVENTION
The field of the invention relates generally to reservoirs the storing of liquid and in particular to a submarine reservoir for the storage of water.
BACKGROUND OF THE INVENTION
The storage of water can be a particular problem in urban environments. Many urban environments have developed in coastal areas where there is a relatively high rainfall. If the run-off from these urban areas in the form of urban stormwater could be captured and reused, the need to build more dams could be delayed or removed altogether.
It is common for water catchments to be in the form of a dam across a river valley. These dams are very expensive to construct and often consume large amounts of valuable agricultural land. Such dams also destroy all pre-existing life in the river valley and the plant material captured within the artificial lake can result in the generation of significant amounts of greenhouse gases from decomposing plan material. Although in some cases this greenhouse gas production can be offset by the production of hydroelectricity, generally speaking it is not desirable to build dams.
In many geographic locations it is common for a source of fresh water to be located relatively close to an urban environment but this source of fresh water may not be suitable for capture by a conventional means such as a dam. For example, it is common for a fresh water source to be located within 100 km of a denser urban area.
It would be advantageous if there was a manner in which these currently unutilised sources of water in or near urban areas could be captured and utilised for the provision of water to these urban areas.
SUMMARY OF THE INVENTION
In a first aspect the invention provides a method of storing water comprising restraining at least one flexible storage reservoir in a submerged position within a body of salt water; establishing a terrestrial intake in fluid communication with the flexible storage reservoir; and establishing a terrestrial outlet in fluid communication with the flexible storage reservoir for the release of stored water.
This method provides the advantage that valuable land is not consumed for the storage of water. It also has the further advantage that the more dense salt water results in the free surface of the stored water above the free surface of the salt water in which the reservoir is restrained. This can save significant amounts of power when the water is being recovered from the reservoir.
In one embodiment of the invention, the intake and the outlet are in fluid communication with the flexible storage reservoir via a common conduit. This conduit can have the fluid from the intake and the outlet partitioned from each other or in a common pipe. The intake and outlet may also be common (i.e. embodied in a single unit).
In one form, there are at least two flexible storage reservoirs and these reservoirs are in fluid communication with each other by means of an interconnection manifold.
Where more than one source of water is available for capture, an embodiment of the invention may involve establishing more than one terrestrial intake for the capture of water from, for example, rivers, stormwater channels or rainwater systems.
The various sources of water typically have different supply characteristics. For example, stormwater run-off usually provides a high volume of water in a relatively short time period. The extent of water captured in this situation can be improved by the provision of a surge tank in fluid communication with the terrestrial intake. When a storm surge occurs the excess flow can be accumulated within the surge tank and then over time can pass to the storage reservoir.
The surge tank can be formed by one of many methods. The tank can be in the form of a conventional concrete tank but such tanks can be quite obtrusive. Alternatively, the surge tank can be formed by terrestrial excavation where situations permit. This offers the advantage of concealing the surge tank.
The surge tank does not have to be located on a coastal fringe. It could be, for example, located in the hills or mountainside remote to the storage reservoir and/or remote to the intake.
In some situations, the water in its captured form may not be suitable as potable water. In these situations, an embodiment of the invention may involve the additional step of treating the water from the terrestrial outlet. Treatment may also occur at the intake.
In a further aspect of the invention there is provided a method of licensing stored water wherein the cost of a license is based on the catchment area upstream of the terrestrial intake. Alternatively, the cost can be based on the average volume of water that passes through the terrestrial intake over a time period. Other possible licensing models include models where the cost is based on the maximum storage capacity of the storage reservoir or the utilisation of that capacity over a given time period.
In a further aspect, the invention provides a flexible water storage reservoir for use with a submerged water storage system comprising a flexible fluid impervious container, at least one manifold attachment means, at least one manifold positioned within the container, the at least one manifold attachment means being arranged to keep the at least one manifold in a position such that water flow can be maintained as the storage reservoir is emptied.
The positioning of the manifold is important when water is being drawn from the storage reservoir. In some circumstances, it is possible for pockets to form in the flexible storage reservoir walls, these pockets inhibiting the extraction of water from the storage reservoir. The positioning of the manifold can mitigate this.
There are several configurations of manifolds that can facilitate the extraction of water from the storage reservoir. In one embodiment, the manifold is elongate and a water inlet stream and a water outlet stream enter and exit at opposite ends of the manifold. In another embodiment, a water inlet stream and a water outlet stream enter and exit via different manifolds.
The extraction of water from the storage reservoir can also be facilitated by the provision of a support that prevents walls of the flexible container from inhibiting the water flow as the storage reservoir is emptied. The flexible container may also be provided with a pressure relief valve that prevents damage to the flexible container from excess pressure.
In an alternate embodiment of the invention, the container further comprises an attachment mechanism for attaching the flexible water storage reservoir into configuration with one or more other flexible water storage reservoirs. This attachment mechanism enables the storage reservoirs to be assembled into a number of different configurations. These configurations include, for example, placement next to each other or stacking on top of each other. In one particular embodiment, the attachment mechanism allows the flexible water storage reservoirs to be configured and locked into a honeycomb configuration. This honeycomb configuration minimises the space between the reservoirs and this in turn minimises the amount of space available for marine life to grow on the reservoirs. Also, when the reservoirs are in this configuration, the outer reservoirs in the configuration protect the inner reservoirs from damage.
In a further aspect, the invention provides a water storage system comprising a plurality of flexible water storage reservoirs wherein the manifold for the or each of the reservoirs are interconnected using an interconnection manifold.
In a particular embodiment of this system, the flexible water storage reservoirs are arranged into a honeycomb configuration.
In other embodiments, the interconnection manifold is in fluid communication with either or both of a terrestrial intake and a terrestrial outlet.
Embodiments of the system may also have a surge tank in fluid communication with the terrestrial intake. When appropriate, embodiments of the invention can have this surge tank formed by terrestrial excavation. Embodiments of the system can also have a water treatment plant connected to the terrestrial outlet (or even to the intake).
When embodiments of the system are positioned in a body of salt water, the flexible water storage reservoirs can be anchored in position to prevent them moving out of position. Also, when the flexible water storage reservoirs are in position, the anchoring can prevent potentially buoyant storage reservoirs from moving.
In a further aspect, the invention provides a water storage system comprising a flexible storage reservoir submersible in use within a body of salt water; and a terrestrial reservoir positionable terrestrially in use and in fluid communication with the storage reservoir; wherein the system is configured such that there is no restriction to water flowing from the storage reservoir to the terrestrial reservoir.
In particular embodiments, of the total mass of water stored, the mass of water held in the terrestrial reservoir above the free surface of the body of salt water is approximately 2.5% of the total mass stored. This mass of water held above the free surface of the saltwater can be utilised to raise the water into reservoirs or other locations for use as a source of water. Such a mass can also be held above the free surface of salt water through the action of the salt water body on the flexible storage reservoir.
In particular embodiments, valves may be used that are configured into a charging state where water head pressure from the terrestrial reservoir forces the water into the storage reservoir. After charging, the valves may be reconfigured into a discharge state where conserved head pressure forces the stored water through an auxiliary line such that a portion of the stored water is pushed to a remote location.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention will now be described by way of example only, with reference to the accompanying drawings in which:
FIG. 1A shows a sectional view of a first embodiment of a water storage system;
FIG. 1B shows a plan view of the water storage system of FIG. 1A ;
FIG. 1C shows a sectional view of the water storage system of FIG. 1A ;
FIG. 2A shows a sectional view of a further embodiment of a water storage system;
FIG. 2B shows a plan view of the water storage system of FIG. 2A ;
FIG. 3A shows a sectional view of a further embodiment of a water storage system in inland configuration;
FIG. 3B shows a plan view of the water storage system of FIG. 3A ;
FIG. 4 shows a further embodiment of a water storage system configured with a geographically remote terrestrial intake; and
FIGS. 5 a and 5 b show sample reservoir storage calculations;
FIGS. 6 A to 6 C show various flexible storage reservoirs.
DETAILED DESCRIPTION
In the description that follows similar reference numerals are used to indicate similar elements in different embodiments of the invention.
FIGS. 1 to 4 show various configurations of possible embodiments of the water storage system. FIG. 1 shows a water storage system 10 having five flexible storage reservoirs in the form of containers 12 restrained in a body of salt water 14 and in fluid communication with a terrestrial intake 16 positioned in the land 17 and a terrestrial outlet 18 located adjacent the body of saltwater 14 .
In use, water from for example, a river, stormwater or rainwater passes in through the terrestrial intake 16 and thence into the containers 12 . Water can be withdrawn from the containers 12 by drawing water from the terrestrial outlet 18 .
In this embodiment, a water storage tank 26 has also been excavated into the rock as a surge tank. In alternate embodiments, this tank can be in the form of a conventional aboveground tank such as a concrete or steel tank. The tank 26 acts as an accumulator to allow surges in the flow of water to be buffered until the water has had time to pass through the terrestrial intake 16 and into the containers 12 . This ability to buffer the water increases the extent of water capture by the system and can decrease overflow losses.
Water can be drawn from the outlet 18 for typical stored water uses. For example, the water can be passed into a water treatment plant (not shown) for subsequent distribution as domestic potable water. Other applications include using treated or untreated water in industrial and agricultural applications (eg. irrigation).
The intake 16 and the outlet 18 are connected to the containers 12 by separate conduits 20 . The use of separate conduits facilitates the mixing of water within the containers 12 . However, the intake 16 and the outlet 18 can share a common conduit which can decrease the cost involved in implementing the system. The conduits 20 can be cut into the rock and can then continue as seabed pipes to the containers 12 .
The containers 12 are connected to each other by an interconnection manifold 22 which takes water from extraction manifolds 24 positioned within each of the containers 12 . The interconnection manifold 22 passes water to and from the conduits 20 and distributes the water between the containers 12 .
In the embodiment shown in FIG. 1 , there are two extraction manifolds 24 in each container 12 . An inlet manifold 28 receives water from the intake 16 and an outlet manifold 30 withdraws water from the container. In other embodiments of the invention, a single manifold can act as both the inlet and outlet manifold.
In an alternate embodiment, there are two interconnection manifolds located at opposing ends of a container. These interconnection manifolds are connected to opposing ends of a combination inlet/outlet manifold. In use, water from an intake passes into the container via the first of the manifolds and water is passed from the container to an outlet via the other manifold.
Referring now to FIGS. 6A to 6C several configurations for the containers 12 are shown. Different configurations of both the shape of the containers 12 and configuration of the extraction manifolds 24 are shown.
FIGS. 6 A(i) and 6 A(ii) show an embodiment of the system in an empty state and a full state respectively, with the extraction manifolds 24 positioned within the container 12 . A vertical support 34 projects from the rigid base 36 of the container 12 and, in use, supports a flexible membrane 38 of the container 12 when the container 12 is in an empty state.
Each of the manifolds 24 are attached to an attachment mechanism 32 which is integrated into the support 34 . The positioning of the manifolds 24 on the support 34 with the attachment mechanism 32 , assists in maintaining the flow of water by preventing the flexible membrane 38 from obscuring the water ports on the extraction manifolds 24 . The container 12 is also provided with a pressure relief valve 44 . The pressure relief valve 44 prevents damage to the container 12 if excess water pressure builds up within the container 12 .
An alternate embodiment of the system in both an empty and full states is shown in FIGS. 6 B(i) and 6 B(ii). In this embodiment, four extraction manifolds 24 (two inlet and two outlet manifolds) float at a distal end 40 of a vertical support member 34 which projects from a rigid base 36 of the container 12 . In this embodiment, as the container 12 moves towards an empty state, a void is maintained in the region below the distal end 40 of the vertical support member 34 where the flexible membrane 38 drapes over the support and the extraction manifolds 24 .
In this embodiment, the four extraction manifolds 24 are buoyant and slidable along the support 34 .
Another alternate embodiment of the system in both empty and full states is shown in FIGS. 6 C(i) and 6 C(ii). In this embodiment, the hexagonal shaped containers 12 are interconnected into a stacked honeycomb configuration. This honeycomb arrangement has the advantage that as the containers 12 approach an empty state, the extraction manifolds 24 from vertically aligned containers 12 stack upon each other to assist in preventing the flexible membrane 38 from obscuring the water ports on the extraction manifolds 24 .
To facilitate the locking of the containers 12 into a given configuration, locking elements 42 as illustrated in FIG. 6 C(iii) are provided at the margins of the containers 12 . Alternate male and female locking elements are provided on opposing sides of the containers 12 to allow a series of similar containers to be locked into configuration.
In alternate embodiments, oval or rectangular containers can be stacked into a similar close-packed configuration. By positioning the containers into a stacked configuration, the space available for marine life to establish between the containers is minimised. The stacked configuration also offers the advantage that the outermost containers protect the inner containers from damage. Therefore, even if there is animal attack upon the system, or other damage such as storm damage, the outermost containers provide a sacrificial barrier to the inner containers.
In order to prevent contamination of the stored water in a non-damaged container by a rupture in a now damaged container, the system is also provided with a salinity monitor 46 . When an increase in the saline content of the container 12 is detected, a valve operates to isolate the extraction manifold 24 of the contaminated container 12 from the interconnection manifold 22 .
There are several possible ways in which the containers 12 can be secured to the floor of the body of saltwater. In one embodiment, nylon anchors are drilled into the seabed and the containers 12 are tethered to these anchors. In an alternate embodiment, the containers 12 can use concrete weights in pouches in each container 12 that can act as ballast. The method by which the containers 12 are secured to the floor of the body of sea water may also be a function of location. For example, if the containers are to be positioned on the floor of a lake, use of concrete weights may be sufficient to secure the containers 12 . However, if the bags are to be positioned out to sea, a more robust securing mechanism such as the nylon anchors may likely need to be utilised.
FIGS. 2 to 4 illustrate alternate embodiments of the submarine water reservoir.
In FIG. 2 , a system is set up in a coastal configuration with a water surge tank 26 positioned adjacent a river 48 . A feed conduit 50 diverts water from the river 48 into the surge tank 26 . The surge tank 26 and a terrestrial outlet 18 are connected to the containers 12 by means of conduits 20 . These conduits are positioned on the riverbed. The outlet 18 is connected to a water treatment plant (not shown). In use, a surge in water flow from the river can be accumulated in the tank 26 until the water has had sufficient time to pass down the conduit 20 to the storage container 12 .
In FIG. 3 , a system is shown in an inland configuration. In this embodiment, once the conduits 20 have been primed with water, the volume of water displaced from containers 12 by the dense sea water maintains the conduits in the primed state and decreases the cost of pumping required to extract water back from the containers 12 . In such a system, a single conduit can be used for both the input and output of water from the containers 12 .
In FIG. 4 , a system is shown with the primary intake 16 spaced several hundred kilometres away from the containers 12 . A surge tank 26 is provided adjacent to a remote river with a feed conduit 50 diverting water into the surge tank 26 . A secondary intake 16 ′ is also provided in this embodiment. Both primary intake 16 and the secondary intake 16 ′ are connected to a common interconnection manifold 22 to then interconnect the containers 12 to the intakes.
When the water needs to be conveyed large distances, a pump may be used to increase the head pressure in the conduit 20 that carries the water to the containers 12 .
FIG. 5 shows sample reservoir storage calculations. Once the storage requirements for a location are determined, system components can be selected to achieve a given storage requirement. In FIG. 5A , the design requirements for a 10,000,000 L system are shown.
In FIG. 5B , a catchment area and a catchment volume for the catchment area are calculated. In this example, the roof area of a stadium is calculated to generate 10,000,000 L/annum of water for storage.
In the licensing of these systems, the cost of the licence can be determined using various parameters. For example, the licence cost can be based on the catchment size or the storage size. The cost can be based on the average annual water catchment volume over a time period or the area of catchment. Alternatively, the cost of the licence can be based on maximum storage capacity for storing water or the utilisation of that capacity. A cost can be calculated by determining the catchment volume and then multiplying this value by a unit cost. This cost can then be paid annually by a licensee.
Although the present invention has been described with reference to particular embodiments, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms. For example, the flexible storage reservoirs can be restrained by pylons. Also, other conventional water treatment steps may be used in conjunction with the system. For example, pretreatment may be performed on the water before entering the storage reservoirs. | A method of storing water by restraining at least one flexible storage reservoir in a submerged position within a body of salt water; establishing a terrestrial intake in fluid communication with the flexible storage reservoir; and establishing a terrestrial outlet in fluid communication with the flexible storage reservoir for the release of stored water. | 4 |
[0001] The present invention relates generally to computer graphics, and more specifically to methods of, and systems for, configuring, controlling and accessing multiple hardware graphics layers that are used to compose a single video display.
BACKGROUND OF THE INVENTION
[0002] Windows-type operating systems allow users and developers to interact with software applications via a consistent graphical user interface (GUI), while at the same time providing them with the ability to interact with multiple software applications simultaneously. Ideally, an operating system should provide access to as much of the underlying graphical hardware's capabilities as possible while maintaining a consistent API (application program interface). An operating system API is the set of routines, protocols, and tools that make up the interface between the operating system and the software applications that access it. Any interaction between a software application and the operating environment (i.e. video display, hard drive, keyboard, etc.) is done through the operating system API.
[0003] Additionally, the operating system should support a degree of feature transparency. That is, a software application should be able to benefit from a system feature without requiring the software application to be aware of every detail of the system feature. For example, a software application designed on a system with a 16 bit colour depth display should run as intended on a system with a 32 bit colour depth display. The software application should not need to know the supported colour depth of the video display it is running on. The greater the degree of feature transparency provided by an operating system, the greater the ease of developing software applications that can run in a variety of environments and the greater the selection of software applications available to use with any given platform.
Video Memory, Video Surfaces and Layers
[0004] Personal computers and other computing devices generally include a circuit board referred to as a graphics card, video card or video board, which allows the personal computer to drive a physical display such as an LCD (liquid crystal display) or a CRT (cathode ray tube) monitor. These graphics cards typically contain their own video memory, so that the computer's RAM (random access memory) is not needed for storing video display data. Many graphics cards also have their own on-board microprocessor so that the processing required to render graphics can be performed very quickly and without being a burden to the main microprocessor of the computer.
[0005] Graphics cards typically have much more video memory than needed to store the contents of a single display screen. The contents of the video memory is partitioned into chunks which can be dynamically defined and redefined, each chunk having a specific width, height and other characteristics. Each chunk is referred to as a video “surface”, one of these video surfaces being treated as the primary display. Drawing to the video surface associated with the primary display will yield visible graphics on the physical display. Drawing to video surfaces other than the primary display will not be visible unless the contents of those surfaces are “blitted” to the primary display's video surface.
[0006] “Layers” hardware allows a graphics card to have one or more video surfaces as part of the primary display. The way the various video surfaces are combined and/or blended to create the primary display is configurable via the layers hardware on the graphics card. The layers hardware combines all the surfaces targeted at the primary display non-destructively. That is, the contents of the various video surfaces are not affected by the layering hardware—only the end result visible on the display device is affected. This makes graphics cards with layering hardware ideal for low performance platforms that require sophisticated graphics composition such as automotive telematics systems, where, for example, it might be desirable to display the settings of ventilation systems over a road map or video programming while it continues to play.
[0007] “Automotive telematics systems” refers to the technology of computerized control systems to manage environmental and entertainment systems in automobiles. These systems are also referred to as automobile “infotainment” or “infotronic” systems, or by other similar names. Some of the functionality that such systems may manage includes:
1. supporting entertainment applications such as broadcast radio, video games and playing movies. These entertainment applications can be selectively directed towards different display, speaker and headphone systems in the vehicle; 2. managing vehicle climate control systems; 3. providing Internet access, email and instant messaging services; 4. providing security systems such as anti-theft and automatic dialling; 5. interfacing and synchronizing with portable computing devices such as personal digital assistants (PDAs), laptop computers and notebook computers; 6. displaying electronic road maps, using GPS (global positioning system) technology to select the correct map and to identify the vehicle's actual position on the map. This technology can also be used to advise the user of nearby service stations, restaurants and the other services, provide traffic information, navigation advice and parking availability; and 7. interacting wirelessly with gas station “point of sale” and associated automated banking services; for example, allowing users to purchase gasoline, have their car washed and download movies without having to interact with a live attendent (see for example, “The eGasStation Architecture—Java™ Technology Based Managed Services for Retail Service Stations” by Sun Microsystems, Inc. 2001).
This listing is just a small sample of what automobile telematics systems may be designed to support. Additional services will surely be supported by telematics systems over time.
Existing Video Systems
[0015] There are two common configurations of video systems in the art.
[0016] In one system, a software application draws images, vectors and characters using an API of the operating system which directly manipulates the memory and registers of the graphics card, to affect a display. The software application uses the operating system API, but the software application itself acts as a graphics driver directly manipulating the hardware. In such a system only one software application has access to the graphics card at one time due to hardware contention issues.
[0017] In the other system, the software application draws using an API of the operating system which packages and sends out the draw requests. If the packaged draw requests are delivered to a software application that is using an API of the operating system to manipulate the memory and registers of the graphics card to affect a display, those draw requests are rendered to the graphics card and may affect the visible display. In this configuration, the drawing applications and the graphics drivers are separate software processes allowing multiple applications to draw using a single graphics card. The mechanism for delivering the packaged draw requests varies within windowing systems known in the art.
[0018] FIG. 1 presents a block diagram of a typical arrangement for a graphics card with layers support 10 , as known in the art. When a software application 12 wishes to draw an image, character or vector to the display screen 14 , it sends a “draw” request to the API 16 of the operating system 18 . The operating system 18 processes the draw request and sends appropriate instructions to the graphics card 20 . These instructions are sent via the operating system API 16 , and the API 22 of the graphics card 20 . Because the operating system 18 has no knowledge of the hardware layers 24 in the graphics card 20 , all draw requests are simply going to be passed to the same layer, the primary layer 26 . The video image within the primary layer 26 is then passed on to the display screen 14 .
[0019] If the software application 12 has special knowledge of the API 22 of the graphics card 20 and the rest of the system allows it, then the software application 12 can pass messages directly to and from the graphics card 20 to manipulate the memory and registers of the graphics card 20 (this is the first method described above). Alternatively, if the operating system 18 has a graphics driver with special knowledge of the API 22 of the graphics card 20 and the rest of the system allows it, then the graphics driver in the operating system 18 could manipulate the layers capabilities of the graphics card 20 (this is the second method described above).
[0020] APIs to access and control video hardware layers were first provided by graphics card manufacturers who were producing graphics cards with layers support. However, there were at least two major problems with these early APIs:
1. the APIs from different manufactures bore little resemblance to one another, meaning that a software application that needed to access and control the layers feature of a graphics card would work only on one manufacture's graphics card; and 2. windows-type operating systems were completely unaware of the existence of the video hardware layers, so the layers could not be accessed via the operating system API.
[0023] More recently an operating system API became available which presented a consistent but limited interface to hardware layering capabilities, although it was still necessary for a software application to use this specific operating system API to be able to render to the layers supported by the hardware. This limitation made the integration of third, party software into a layer-enabled system impossible. In other words, this new operating system API still requires that third party software applications know that the new operating system API has access to the hardware layers, and know how to use it. Typically, third party software applications do not have this knowledge, so this is not a “transparent” solution.
[0024] One such API is “DirectFB”—an API which provides generic access to video layers capabilities in a limited fashion. DirectFB is limited to exclusive use of surfaces, with the ability to share the primary display surface to a degree.
[0025] Existing operating system APIs that allow a software application to have direct access to a graphics hardware layer, generally preclude that layer from being shared by multiple software applications due to hardware contention issues.
[0026] Demand has grown in the automotive, medical instrumentation, consumer, and industrial automation markets for a graphics solution which allows the use of third party software applications, legacy applications, and new software applications that were targeted at more than one project, to be able to leverage the layering capabilities of the chosen graphics hardware.
[0027] There is therefore a need for an integrated approach to configure, control, and access (render to) graphical hardware layers which addresses the problems outlined above. The approach chosen must take into account the needs of the target markets:
[0028] Automotive: Very size and performance sensitive
[0029] Consumer: Very size and performance sensitive
[0030] Medical: Very performance sensitive
[0031] Industrial Automation: Very performance sensitive
[0000] This design must also be provided with consideration for speed of execution, reliability, complexity and scalability.
SUMMARY OF THE INVENTION
[0032] It is therefore an object of the invention to provide a novel method and system of computer file management which obviates or mitigates at least one of the disadvantages of the prior art.
[0033] One aspect of the invention is broadly defined as, in a computer environment including a software application and an operating system running on a computer, said computer including a graphics card and a video display, said graphics card being operable to render images to said video display, the improvement comprising: said operating system including a universal application programming interface (API) which supports hardware layers on graphics cards; said operating system being operable to: receive draw events via said universal API; determine what hardware layers are available on said graphics card, and what their parameters are; and respond to draw requests from said software application by rendering said draw requests selectively to any of said available hardware layers on said graphics card; whereby said computer environment allows software applications to exploit available hardware layers on said graphics card.
[0034] In the preferred embodiment of the invention, a mechanism is provided which allows the windowing environment and layers hardware to be configured such that software applications that do not know about video layers can, in fact, render to layers. That is, software applications can render to layers without using the video layers APIs at all and not using any special draw commands. This mechanism allows the use of unmodified legacy applications in a layered environment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings in which:
[0036] FIG. 1 presents a block diagram of a computer system with video layers support as known in the art;
[0037] FIG. 2 presents a block diagram of a computer system with video layers support in an embodiment of the invention;
[0038] FIG. 3 presents a symbolic visualization of the Photon™ Event Space and the QNX™ operating system environment in an embodiment of the invention;
[0039] FIG. 4 presents a symbolic visualization of a modified Photon Event Space supporting video hardware layers management, in an embodiment of the invention;
[0040] FIG. 5 presents a flow chart of a method of configuring video layers support, in an embodiment of the invention;
[0041] FIG. 6 presents a diagram of a default window manager console layout, in an embodiment of the invention; and
[0042] FIG. 7 presents a flow chart of a method of handling draw events, in an embodiment of the invention.
DESCRIPTION OF THE INVENTION
[0043] Generally speaking, the invention addresses the problems in the art by providing an operating system which:
1. has a universal API which supports hardware layers on graphics cards; 2. determines what layers are available on the graphics card in use, and what the parameters of those layers are; and 3. reacts to draw requests from software applications by exploiting the available video layers.
This system provides feature transparency for rendering to graphical hardware layers. A number of embodiments of the invention are described herein, but clearly the invention can be implemented in many different ways. The block diagram of FIG. 2 presents an overview of a typical system employing the invention.
[0047] The block diagram of FIG. 2 , may be contrasted to that of FIG. 1 . In the case of FIG. 2 , when a software application 32 wishes to draw an image, character or vector to the display screen 14 , it may or may not have knowledge of the layers support available. Thus, the system 30 supports two different types of draw requests to the API 34 of the operating system 36 : requests which include hardware layer information 38 , and those which do not 40 .
[0048] The operating system 36 of the invention has an API 34 which supports targetting draw requests to video surfaces (which can be associated to layers) 38 , but also supports non-targetted draws. In order to support legacy third-party software applications, the operating system 36 must handle non-layers type requests 40 in the traditional manner. Alternatively, two classes of draw API could be defined: the traditional API which would provide a non-targetted and thereby non-layer capable API, and a surface or layer draw API which would provide direct access to video surfaces and thus layers.
[0049] The operating system 36 also has some means of determining what layers are available on the graphics card 20 . This knowledge could be transferred from the graphics card 20 to the operating system 36 in various ways, for example: on each boot-up, as part of the system installation, or via hard-coding. Operating systems 36 are typically designed to include software “drivers” which are specific to output devices such as graphics cards. When a user installs a new graphics card, part of the installation procedure will include the loading of the graphics cards driver onto the system. These drivers are generally specific to the particular operating system, and make and model of graphics card. Drivers are often distributed with the graphics cards on CD-Roms, but are also generally available online.
[0050] Note that the invention does not require any changes to the graphics card 20 and display 14 as described with respect to FIG. 1 . The software application 32 may also be the same as the software application 12 , if it does not have knowledge of the available layers and the capability to request that certain video hardware layers be used.
[0051] On receipt of a draw request, the operating system 36 processes the request and sends appropriate instructions to the graphics card 20 via the API 34 of the operating system 36 and the API 22 of the graphics card 20 . Unlike the system of FIG. 1 , where the operating system 36 has no knowledge of the hardware layers 24 in the graphics card 20 , the operating system 36 in the case of the invention does have knowledge of the hardware layers 24 and also has a driver within the API 34 which is complementary to that of the graphics card 20 . Thus, draw requests are directed to the layer determined by the operating system 36 —in some cases this video hardware layer will be determined by the software application 32 wishing to draw an image, character or vector, but in other cases the determination will be made by the operating system 36 itself using the geometry of the emitted events, the geometry of draw sensitive regions and the priority of the data. This allows the control of what elements are delivered to which regions positionally.
[0052] A typical example would, for example, have alert renderings occurring positionally under a region associated with a layer that has priority over other video surfaces, ensuring the alerts are visible over all other content, climate data or a movie being shown in the composited display.
[0053] These layers of images are all stored separately on the graphics card 20 and are composed non-destructively into a single composite image. The composite video image is then sent by the graphics card 20 to the display screen 14 for presentation.
[0054] The system of the invention allows graphics card hardware layers to be exploited by any third-party applications software, regardless of whether it has knowledge of the underlying hardware layers. It also provides a uniform interface, so that software applications do not have to be aware of the specifics of a particular graphics card. Other advantages of the invention will be clear from the more detailed description of the invention which follows.
[0055] The preferred embodiment of the invention will be described with respect to the Photon™ Windowing System running over the QNX™ RTOS (real time operating system) though the invention could be implemented on virtually any operating system. Variations necessary to apply the invention to other operating systems would be clear to one skilled in the art from the description herein.
[0056] A symbolic visualization of the Photon event space and the QNX operating system environment 50 in an embodiment of the invention, is presented in FIG. 3 .
[0057] The QNX operating system is a “message passing operating system”. This means that all of the software including software applications, the operating system itself and windows GUI (graphic user interface) software, run as separate software processes on the system. These software processes are depicted as blocks in section 52 of FIG. 3 . Message passing is the fundamental means of interprocess communication (IPC) between these software processes. A message is a packet of bytes passed from one process to another with no special meaning attached to the content of the message. The data in a message has meaning for the sender of the message and for its receiver, but generally for no one else.
[0058] The Photon environment 50 provides a three dimensional virtual “Event Space” 54 where the user 60 can be imagined to be outside of this space, looking in. The Photon environment 50 confines itself only to managing “Regions” owned by application programs, and performing the clipping and steering of various “Events” as they flow through the Regions in this Event Space 54 . Software applications can place regions into this Event Space 54 , which are sensitive, opaque, or both to various types of events which may be passed through.
[0059] Software applications can exert an influence on the Photon environment 50 through one or more of these rectangular Regions, which are owned by the respective software processes themselves. For example, a particular Photon application 56 may generate a Region 58 . Regions can also emit and collect objects called Events. These Events can travel in either direction through the Event Space 54 (i.e. either toward or away from the user 60 ). As Events move through the Event Space 54 , they interact with other Regions—this is how software applications interact with each other. Regions are stationary, while Events move through the Event Space 54 .
[0060] As an Event flows through the Event Space 54 , its rectangle set intersects with Regions placed in the Event Space 54 by other software processes. As this occurs, the operating system adjusts the Event's rectangle set according to the attributes of the Regions with which the Event intersected.
[0061] Events come in various classes and have various attributes. An Event is defined by an originating Region, a type, a direction, an attached list of rectangles and optionally, some Event-specific data. Events are used to represent the following:
[0062] key presses, keyboard state information;
[0063] mouse button presses and releases;
[0064] pointer motions (with or without mouse button(s) pressed);
[0065] Region boundary crossings;
[0066] Regions exposed or covered;
[0067] drag operations; and
[0068] drawing functions.
[0069] The normal operation of a graphics driver 64 is to create a region in Photon's event space 54 with the same dimensions as the physical display device 14 and sensitivity to draw events. Any software application that emits a draw event (for example, output event 66 ) from the area underneath the graphics driver's region will have its events intersect with the graphics driver's region and the event's data will be delivered to the graphics driver. The graphics driver 64 uses the data from the draw event (photon draw stream) to render the desired graphics to the video hardware 20 , and on to the physical display device 14 .
[0070] A Region has two attributes which control how Events are to be treated when they intersect with a Region: Sensitivity and Opacity. If a Region is sensitive to a particular type of Event, then the Region's owner collects a copy of any Event of that type which intersects with the Region. The sensitivity attribute neither modifies the rectangle set of an Event nor does it affect the Event's ability to continue flowing through the Event Space. Regions which are opaque to a specific Event type block portions of that type of Event's rectangle set from travelling further in the Event Space. If a Region is opaque to an Event type, any Event of that type which intersects with the Region has its rectangle set adjusted, to clip out the intersecting area. If the Event is entirely clipped by the intersection of an Opaque Region, the draw Event will cease to exist.
[0071] The following table summarizes how a Region's attributes affect Events that intersect with that Region:
[0000]
If the Region is:
then the Event is:
and the rectangle set is:
Insensitive, Transparent
ignored
unaffected
Insensitive, Opaque
ignored
adjusted
Sensitive, Transparent
collected
unaffected
Sensitive, Opaque
collected
adjusted
[0072] By placing a Region across the entire Event Space, a process can intercept and modify any Event passing through that Region. If a Region is Sensitive and Opaque, it can choose to re-emit a modified version of the Event.
[0073] A special Region called the root Region 62 is always the Region furthest away from the user 60 . All other Regions descend in some way from the root Region 62 . Once an Event travelling away from the user 60 reaches the root Region 62 , it ceases to exist.
[0074] The current invention extends this concept to allow software applications to render to “off screen contexts” or “video surfaces” that do not have physical representation in Photon's event space. To achieve this, an identifier provided by the graphics driver at the time the video surface was created, is inserted into the draw stream that uniquely identifies that video surface. The graphics driver can then render draw requests directly into the video surface identified.
[0075] In other words, a software application can launch a software process which emits an output event in the Photon event space 54 . This output event can include an identifier which indicates which video layer the output event is to be directed to. The graphics driver responds to the existence of the identifier by generating the requested video surface, including the video surface identifier, in order to render into that surface.
[0076] The events containing draw streams to be targeted at specific video surfaces may be emitted directly to the graphics driver's region. In other words, the draw stream targeted at a particular video surface could be given directly to the graphics driver without traveling through the Photon event space 54 , eliminating the possibility of a region blocking some or all of the draw event's rectangles. To provide transparent access to hardware layers, two ideas were combined:
1. the facility for a graphics driver to create a driver region in Photon's event space 54 that would have any draw stream collected on that region rendered to a video surface was added (i.e. the driver region acts like a collector, events that match its sensitivity are delivered to the graphics driver); and 2. the ability to associate an off screen context or video surface to the layer hardware on the graphics card was also added.
[0079] By providing an API and supporting driver that allows software applications to query the number of available hardware layers, determine what capabilities each hardware layer supports, create off screen contexts/video surfaces which match any restrictions imposed by the hardware layers, request that a driver region be created in Photon space targeting that surface, and finally, associate the surface to a facet of the layering hardware and configuring the layering hardware's capabilities, any software application can be given access to a layer without having to modify the software application in any way and without the software application even knowing the video hardware layers exist.
[0080] A configuring application sets up the video surfaces, driver regions, surface to layer associations, and layer attributes. Once done, any software application that is positioned under the driver regions the configuring application requested, will render to the surface targeted by that driver region and subsequently to the primary display through the layering hardware.
[0081] FIG. 4 presents an exemplary graphic representation of this concept. Note that:
a layer will composite the contents of a video surface it is associated with, to the primary display (recall that a video surface is a software entity managed on the operating system side of the system, while a layer is a firmware entity on the graphics card); a video surface may or may not be associated with a layer; software applications can emit draw streams that are targeted at a particular video surfaces or draw streams that have no regard for the existence of multiple video surfaces; if the draws are not targeted at a specific video surface, the event flows through Photon event space and will be collected by any regions sensitive to draw that the events intersect; and if draws are targeted at a particular video surface, the draw event is delivered directly to a region created by the driver that owns the targeted video surface, bypassing the normal event propagation through the Photon Event Space in which other regions could block or modify the draw event.
[0087] Multiple driver regions can be put into Photon's event space by a single driver, which targets video surfaces other than the one associated with the primary display. This in effect causes any software application below that region to render to the video surface the driver region is associated with-without the software application knowing where the draws are ultimately going.
[0088] If such a region is targeting a video surface that is associated with a layer, the draw commands from the software applications below the driver region will be rendered to the video surface and composited by the layer.
[0089] So, software applications do not explicitly render to a layer; they render either through Photon space to whomever catches the draws, or to a specific video surface. The fact that a video surface has been associated with a layer does not effect the commands/API that a software application uses when drawing.
[0090] In FIG. 4 , software application APP 1 is drawing through Photon event space 80 . Its draws happen to intersect with a driver region 82 that is targeting the video surface 84 associated with the primary display (the top hardware layer on the graphics card). That is, any draw events that the video driver 94 receives from region 82 will be rendered to surface 84 .
[0091] Software application APP 2 is drawing the same way that APP 1 is, but its draws intersect a driver region 86 that is targeting, or associated with, video surface 88 . This video surface 88 is associated with another layer on the graphics card.
[0092] Software application APP 3 draws using the same drawing API as applications APP 1 and APP 2 , but APP 3 has intentionally set its draw target to be video surface 90 . The mechanism employed has APP 3 's draw stream sent directly to the primary surface region. The draw stream has an identifier informing the collector of the event, the graphics driver, that the draw stream should be rendered to video surface 90 in this case. In FIG. 4 , video surface 90 is associated with the third layer.
[0093] Note again, that the software applications are rendering to video surfaces, not specifically to layers on the graphics card. Video surfaces 88 and 90 could just as easily have had no layer association at all. For the contents of those surfaces to be seen in that case, they would have to be blitted to the layer associated with video surface 84 .
[0094] The layer hardware 92 on the graphics card manipulates the video surfaces 84 , 88 , 90 and pulls them into the graphics pipeline to generate a composite display that is seen on the physical display device 14 . The video surfaces 84 , 88 , 90 are simply defined regions in the video memory 96 of the video hardware, as known in the art.
[0095] Draw instructions generated by the software processes of third party software applications can thus be positioned in any of these video surfaces 84 , 88 , 90 and processed accordingly.
[0096] In the preferred embodiment of the invention, the configuration of the video layers and graphic driver regions in the Photon Event Space shown in FIG. 4 is generated by a separate software process called a “configuring application”. This configuring application could, for example, perform the steps presented in the flow chart of FIG. 5 to set up this environment.
[0097] At step 100 , the configuring application queries the graphics driver for a particular physical display device 14 , for the number of available hardware layers. The graphics driver is dedicated to the particular graphics card 20 , but all Photon drivers that have layers support, have the same interface for query and control of the layers hardware.
[0098] The configuring application then queries the graphics driver at step 102 , for the capabilities of each video layer. This information will contain such parameters as the dimensions of each video layer, the number of colours, dimensions, resolution, scale factors, virtual dimension limits, chroma-key, alpha blending capabilities, and other parameters per the specific environment.
[0099] Armed with this information from the graphics driver, the configuring application then generates the required number of video surfaces (called “off screen contexts” in Photon) at step 104 , and configures the corresponding layers based on the number of, and capabilities of, the available hardware layers, at step 106 .
[0100] The configuring application then optionally places those driver regions into the Photon Event Space 80 at step 108 . This step is optional because it may not be desirable to place all of the driver regions in the Photon Event Space 80 (the lack of a driver region within the photon space for a video surface prevents software applications that do not have specific intent to render to that surface, from doing so inadvertently). As noted above, it may be desirable to send some draw requests directly to a particular video layer without having to pass through the Photon Event Space 80 , avoiding the possibility that certain draw requests might be modified or blocked by other Regions.
[0101] It might be desirable, for example, to configure a layer to present alarm conditions to the user. This layer could be set up outside the Photon Event Space 80 to guarantee that these alarm conditions will be presented to the user 60 regardless.
[0102] At this point, the system is now configured to exploit the hardware layers capabilities of the graphics card.
[0103] The configuring application can then terminate, leaving the Photon system configured as above. Any third party software applications that are positioned under the graphic driver regions targeted at a video surface associated with a layer will in effect render to that layer. The third party software applications do not need any knowledge that the layers even exist so need no modifications whatsoever to render in a multi-layered system.
[0104] At this point, any application which renders from below a driver region, which is connected to a video surface associated with a layer will be rendering into that layer and the hardware will composite the result of the rendering into the final display based on the configuration of the layer's attributes.
[0105] It should be noted that any software application which renders from below a driver region which is connected to a video surface, will be rendering into that video surface. It is not necessary that the video surface also be connected to layering hardware. For example, a screensaver could request a driver region be created at 1024,768 to 2047,1535 and associate that region to a video surface that it will manipulate and display at 0,0. The result would be the screensaver using content from software applications on console 5 , assuming a resolution of 1024×768, to generate its display.
[0106] The default window manager layout in the Photon event space is shown in FIG. 6 . The display framework consists of “consoles” where console 5 is one console to the right, and one down, from console 1 .
[0107] Once the system has been configured, draw requests can be processed in the manner presented in the flow chart of FIG. 7 . This flow chart has been simplified to demonstrate the process flow, as opposed to being representative of how the actual software code would be structured. For example, a real implementation of an operating system would generally not include a “no” loop as shown with respect to step 120 . Operating systems generally respond to the arrival of interrupts, the issuance of function calls, or the response to a periodic poll, rather than sitting in a processing loop waiting for a response. However, the actual software code implementation of the invention would be clear to one skilled in the art from the description of the invention in this simplistic manner.
[0108] When a draw event is received at step 120 , or similarly, any request to render an image, vector or character to a physical display is received, control passes to step 122 . At step 122 , the routine determines whether the draw request is flagged for a specific video hardware layer. If it is not, then the draw event is sent through the Photon Event Space 80 per step 124 . Such events are then delivered to regions within the Photon Event Space 80 at step 125 . The determination of which regions a draw event will be assigned to is determined by the geometry of the source of the draw event. As noted above, it may be desirable, for example, to send alarm displays to regions which have higher priority than video images. In fact, it is necessary to be able to control to which surfaces/layers draw events end up affecting in order to implement a general layered interface.
[0109] If the draw event is identified at step 122 is to be directed to a specific video surface, then it is passed directly to a graphic region without having to travel through Photon space from the emitter region. As noted above with respect to step 108 of FIG. 5 , it may be desirable to pass some draw requests directly to a particular hardware layer, thus avoiding the possibility of the draw request being blocked or modified by another Region. If the draw request is intended for the Photon Event Space 80 , then control passes to step 124 , while if the draw request is intended to go directly to a hardware layer, control passes to step 130 .
[0110] At step 132 , the entire Photon Event Space 80 is processed as described with respect to FIGS. 3 and 4 . This results in the draw event being processed within the Photon Event Space 80 and possibly, being projected onto one or more graphic driver regions.
[0111] These graphic driver regions are associated with particular video hardware layers, and accordingly are rendered onto those video hardware layers at step 134 . If the draw event had been passed to step 130 , then it would simply be emitted directly to the driver region in Photon Event Space 80 bypassing all intervening regions between the source of the draw and the driver region and without regard to the geometry of the draw source or the receiving driver region. The draws are then rendered to the desired hardware layer 134 .
[0112] At step 136 , the video hardware layers are then processed by the graphics card and presented on the physical display screen. Control then returns to step 120 , to await the arrival of further draw events.
[0113] A system arranged in such a manner allows third party software applications to exploit video hardware layers support in graphics cards, without even being aware that such hardware layers exist. Such a system could allow, for example, a television display to supports a computer display or email, in a pip (picture in picture) window. The email feature could be a standard email application that the television displays on a separate layer to allow user configurable transparency control of the email application (so as not to too badly obscure the scores during a sporting event). Similarly, a stand alone mapping application could be put on one layer and automotive info (trip computer info, hvac settings, etc) could be displayed over the map with a minimum of impact on the microprocessor of the system.
[0114] While particular embodiments of the present invention have been shown and described, it is clear that changes and modifications may be made to such embodiments without departing from the true scope and spirit of the invention.
[0115] The method steps of the invention may be embodiment in sets of executable machine code stored in a variety of formats such as object code or source code. Such code is described generically herein as programming code or software code for simplification. Clearly, the executable machine code may be integrated with the code of other programs, implemented as subroutines, by external program calls or by other techniques as known in the art.
[0116] The embodiments of the invention may be executed by a computer processor or similar device programmed in the manner of method steps, or may be executed by an electronic system which is provided with means for executing these steps. Microprocessors, digital signal processors (DSPs), microcontrollers and application specific integrated circuits (ASICs) are typical examples of devices which are capable of such execution. Similarly, electronic memory media such computer diskettes, CD-Roms, Random Access Memory (RAM), Read Only Memory (ROM) or similar computer software storage media known in the art, may be used to store the software code required to perform the methods of the invention. As well, electronic signals representing these method steps may also be transmitted via a communication network. | The present invention relates generally to computer graphics, and more specifically to methods of, and systems for, configuring, controlling and accessing multiple hardware graphics layers that are used to compose a single video display. One aspect of the invention is broadly defined as follows: in a computer environment including a software application and an operating system running on a computer, the computer including a graphics card and a video display, the graphics card being operable to render images to the video display, the improvement comprising: the operating system including a universal application programming interface (API) which supports hardware layers on graphics cards; the operating system being operable to: receive draw events via the universal API; determine what hardware layers are available on the graphics card, and what their parameters are; and respond to draw requests from the software application by rendering the draw requests selectively to any of the available hardware layers on the graphics card; whereby the computer environment allows software applications to exploit available hardware layers on the graphics card. | 6 |
This application is a continuatioin of application Ser. No. 295,870, filed Aug. 25, 1981, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a memory device which can store data even when a main power source is cut off.
Recently, microprocessors are applied to various control operations, such as for adjustment of a desired temperature and the automatic selection of a television channel. With such control device, it is necessary to store data relating to the control conditions, in a read wirte memory. The read write memory is a volatile memory, therefore, some precautionary measures should be taken in case of momentary power failure. Until now, an auxiliary power source (cell or large capacitor) has been connected to the read write memory in order to retain stored data, thereby carrying out the so-called backup process of preventing stored data from being extinguished even when the main power source is cut off. The period is limited, in which the backup process can be continued by a cell or capacitor. Upon lapse of the period, the contents of the memory disappear. Further, even during the backup period, externally generated noises sometimes change the contents of the memory. Where the contents of a memory disappear or are changed, then the control device which carries out various forms of control in accordance with the memory contents, tends to malfunction. As a result, an unexpected accident happens, depending on the type of object device or instrument whose operation should be controlled. In the case of CPU control, the CPU would give rise to an erroneous results.
SUMMARY OF THE INVENTION
It is accordingly the object of the present invention to provide a memory device which can detect any change in altered stored data and prevents altered data from being read out.
To attain the above-mentioned object, the invention provides a memory device which comprises a data-specifying means, a read write memory for storing data specified by the data-specifying means, a read only memory for storing all data capable of being specified by the data-specifying means, and a judgment circuit for reading data from the read write memory and read only memory, comparing the output data from the read write memory with all the output data from the read only memory, and where coincidence does not arise between both output data, issuing a signal denoting noncoincidence.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of an endoscrope type photographing system provided with a memory device embodying the present invention;
FIG. 2 is a flow chart showing the operation of the photographing system;
FIG. 3 shows data stored in a read write memory; and
FIG. 4 indicates data stored in a read only memory.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Description is now given with reference to the accompanying drawings of a memory device embodying the present invention. FIG. 1 is a block diagram of a data photographing system for an endoscope camera which is provided with the memory device embodying the invention. A main power source 10 for supplying power VCC to the respective parts of the photographing system is connected to a power detector 12, an output from which is supplied to a central processor unit (CPU) 14. The CPU controls the whole operation of the photographing system including the photographing of data. A control program for this purpose is stored in a nonvolatile read only memory (ROM) 16, which is connected to the CPU 14 by means of a data bus 18. A read write memory (RWM) 20 for temporarily storing data required for the above-mentioned control is also connected to the data bus 18. The volatile RWM 20 is supplied with not only power from the main power source 10 but also from an auxiliary cell-type power source 22 used to hold data. A keyboard 26 for specifying data, and display section 28 are connected ot the data bus 18 through an I/O port 24. An endoscope camera 32 whose operation is to be controlled is also connected to the data bus 18 through an I/O port 30.
Description is now given of the operation of the photgraphing system of the endoscope camera. The endoscrope camera 32 photographs the coeliac condition of a patient and together with required data such as the kind of endoscope, the identity of the patient, the site of photographing, and the like on the same film frame. If data are specified each time a frame is photographed, then the operation of the endoscope camera is interrupted during this period. Such interuption is objectionable, because a patient into whose coeliac cavity an endoscope is inserted suffers an increased amount of pain. It is therefore preferred that all data be specified by means of the keyboard 26 before the photographing of the first frame, and then stored in the RWM 20. The data is generally held by the main power source VCC. The main power source VCC is normally provided in a light source section of the endoscope photographing system. Power from the main power source VCC is conducted through the endoscope body to the photographing system. An endoscope is sometimes exchanged for a different type, depending on the position of the patient's coeliac cavity which is to be photographed. Since, at this time, the phtographing system is separated from the light source including the main power source VCC, the RWM 20 is shut off from the main power source VCC. Power is supplied from the auxiliary power source 22 instead of from the main power source VCC. When the data photographing system is again connected to the light source through the endoscope, then the RWM 20 holds the data by the power supplied from the main power source VCC.
The CPU 14 performs a control program stored in the ROM 16 in accordance with the data stored in the RWM 20. Now let it be assumed that when the CPU 14 is supplied with power, then the photographing of the patient's coeliac condition and the related data photographing is automatically commenced. Where, in this case, data previously stored in the RWM 20 is extinguished or changed, then the photographing system malfunctions. Description is now given with reference to the flow chart of FIG. 2 of the process of preventing the malfunction of the photographing system.
Assuming that data to be photographed is formed of 8 bytes, for example, of the EA24 M40 pattern (where means a blank). Further, let it be assumed that the first 6 bytes represent data to be photographed with respect to the patient, endoscope, etc., and the remaining 2 bytes denote data on the serial number of a film frame. The above-mentioned 8 bytes data is converted into ASCII code of 1 letter-1 byte. The converted data is stored in the RWM 20 as illustrated in FIG. 3. Now let it be assumed that data characters to be photographed total 39 forms, including the digits from 0 to 9, the alphabet letters from A to Z and notations such as +, - and . These data characters are stored in the ROM 16 in the form of a ASCII of 1 bytes as illustrated in FIG. 4. In FIGS. 3 and 4, numerals indicated in the squares constitute the ASCII code. The characters on the right side thereof represent the actual characters.
As previously mentioned, when supplied with power, the CPU 14 automatically performs a prescribed control program. If data stored in the RWM 20 is ascertained before the execution of the program, then the subject memory device will not malfunction. When the power detector 12 detects the supply of power from the main power source 10, then the CPU 14 commences the execution of a data ascertaining program shown in FIG. 2. At step 202 following start step 200, the read address X of the RWM 20 is set at an intial value of XO. At step 204, data Drwm (XO) is read out of the XO address of the RWM 20. With the foregoing embodiment, E, that is, 45 of the ASCII code is first read out. At step 206, the address Y of the ROM 16 is set at an initial value of YO. At step 208, data Drom (YO) is read out of the YO address of the ROM 16. With the foregoing embodiment, the data Drom (YO) denotes 0, that is, 30 of the ASCII code. At step 210, comparison is made between the data Drwm (XO) and the data Drom (YO). Where data previously stored in the RWM 20 is extinguished or changed, coincidence will never take place between these data Drwm (XO) and Drom (YO). Where normal data is stored in the RWM 20, then coincidence of data will never fail to be attained by shifting the addresses of the ROM 16 one after another, even when the data Drwm (XO) is not equal to the data Drom (YO). Where no coincidence arises between the data Drwm (XO) and Drom (YO), then a judgment is made at step 212 as to whether the read address Y of the ROM 16 represents a maximum address Ymax. If Y=Ymax is not realized, then the address Y is incremented at step 214, and step 208 is again taken. Y=Ymax means that no coincidence takes place between the data stored in the RWM 20 and all the data stored in the ROM 16, that is, data stored in the RWM 20 was not normal. In such case, the display section 28 gives a warning at step 216. Then, the user is advised to suspend the operation of the CPU 14 by a look at the indication on the display section 28 and to supply fresh data to the RWM 20. At this time, the CPU 14 causes the data of the RWM 20 to be set at an initial value. The reason is that when a change takes place in data on the number of film frames, for example, when the film end is to be detected, then the memory device is likely to manlfunction, and consequently data on the number of film frames is set at a minimum value of zero or a maxium value.
When, at step 210, coincidence is judged to take place between the data stored in the RWM 20 and the data stored in the ROM 16, then it is provided that data stored in the RWM 20 is normal and is not extinguished or changed. At step 222, therefore, a judgment is made as to whether all data have been read out of the RWM 20, according to whether the read address X of the RWM 20 has a maximum value of Xmax or not. If X=Xmax is not realized, the address X is incremented at step 224, and later step 204 is taken again. If X=Xmax results, it means that all data stored in the RWM 20 are correct. Consequently, the operation proceeds to a main routine through an end step 220.
After all the data stored in the RWM 20 are judged to be effective, the CPU 14 causes all these data and the image of a foreground subject to be photographed together. Therefore, when the RWM 20 is shut off from the main power source 10, and the memory data is retained only by power supplied from the auxiliary power source 22, should data stored in the RWM 20 be extinguished, the extinction can be detected, preventing the CPU 14 from carrying out erroneous control. Further, where data stored in the RWM 20 are changed due to the occurrence of noise signals, though not extinguished, it is possible to detect any change in any other data from that stored in the ROM 16.
With the foregoing embodiment, a volatile memory is backed up by power supplied from an auxiliary power source. However, it is possible to back-up the volatile memory, for example, by a capacitor. Further, it is possible to ascertain the effectiveness of data stored in the volatile memory not only while it is backed up by the auxiliary power source but also while it is supplied with power by the main power source. In such case, it is advisable to let the CPU 14 perform the program of FIG. 2 not only when power supply from the main power source is detected, but also as often as required. Then it is unnecessary to provide the power supply detector 12. Should an abnormal condition occur in the subject memory device, it is advisable to give an alarm or lock the memory device out of operation. It is not always necessary to set the data sotred in the RWM 20 at an initial value.
The present invention is applicable to devices other than a camera. Namely, the invention can be applied in selecting a television channel, in recording data on a video tape or adjusting a cooler temperature. Obviously, this invention is applicable also to the nonvolatile type RWM. | A memory data coincidence device includes a volatile read write memory connected to a main power source and auxiliary backup power source, and a keyboard for supplying data to the read write memory. The device further includes a read only memory for storing all data capable of being stored in the read write memory and a central processor unit (CPU) which compares the data of the read write memory with all data of the read only memory before it reads data out of the read write memory. If no coincidence takes place, the CPU sends forth a signal denoting the condition that the read write memory is not backed up. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to optical lenses, and more particularly to a contact lens having an opaque simulated iris pattern for cosmetic enhancement and/or visual correction.
[0003] 2. Description of Related Art
[0004] Optical contact lenses are frequently utilized for cosmetic effect. For example, it is known to wear a colored contact lens on the eye in an effort to alter the apparent color of the wearer's iris. Colorants such as dyes or pigments of a desired color or colors are applied to a contact lens in a pattern adapted to overlie the natural iris, thereby altering the natural iris color. Such contact lenses may provide vision correction, or may be solely cosmetic.
[0005] Creating a realistic, natural iris appearance has proven to be difficult with many known color-changing lenses. For example, the natural iris is relatively flat, whereas a typical contact lens has a significant convex-concave curvature adapted to generally match the curvature of the cornea. As a result, the use of a simulated iris pattern applied to either the concave or convex face of a contact lens often creates the unnatural appearance of a curved iris.
[0006] Attempts have been made to provide a color-changing contact lens that imparts a more natural appearance. For example, colorant may be applied to a lens in a non-opaque, color-changing iris pattern that does not completely obscure the underlying natural iris pattern. The pattern may be applied, for example, in the form of a series of colored dots producing an intermittent colored pattern over the iris area of the lens, but leaving a number of uncolored interstices between the dots. The natural iris of the wearer shows through these clear interstices, purportedly providing a more natural iris pattern and giving the appearance of depth.
[0007] It is also known to cut away a portion of a lens blank and imprint a simulated iris pattern onto the surface of the lens blank formed by the cutout. Lens material is then re-cast over the imprinted iris pattern to replace the cutout portion and encapsulate the pattern within the lens body. This process, however, is somewhat labor intensive and time consuming, and is therefore relatively expensive.
[0008] Many color-changing lenses are designated as “opaque” in the marketplace, simply by virtue of their use of colorants that have opaque properties. The manner in which the “opaque” colorants are applied to a lens, however, typically results in the lens pattern itself not being truly opaque. For example, even if the colorant comprising each individual dot is itself opaque, the iris pattern formed by a plurality of such dots is typically not opaque, as light and color are readily transmitted through the interstices between adjacent dots in the pattern. As a result, some of the wearer's natural eye color shows through the lens. This is particularly problematic when a user seeks to change a darker natural eye color to a lighter color.
[0009] Accordingly, it has been found desirable to provide a contact lens having a fully opaque iris pattern for color alteration, but presenting a realistic, natural appearance. It is also desirable to provide an efficient method for manufacturing such a lens. It is to the provision of contact lenses and associated methods of manufacture meeting these and other needs that the present invention is primarily directed.
SUMMARY OF THE INVENTION
[0010] The present invention provides a contact lens having an opaque simulated iris pattern applied thereon, and a method of forming such lenses. As used herein, a lens having an “opaque” iris pattern refers to a lens having a simulated iris pattern that substantially entirely blocks color transmission from the underlying natural iris, which might inhibit the color-changing effect of the lens. The iris pattern preferably provides the appearance of a substantially flat iris for a realistic, natural look. The lens can provide vision correction, or can be solely cosmetic.
[0011] In one aspect, the invention is a contact lens preferably including a lens body formed of substantially transparent material, an opaque simulated iris pattern applied to the lens body; and a layer of polyvinyl alcohol (PVA) overlying the simulated iris pattern.
[0012] In another aspect, the invention is a contact lens preferably including a concave base surface, a convex outer surface, and an opaque simulated iris pattern upon the contact lens along one of the concave base surface and the convex outer surface; and a layer of PVA overlying the simulated iris pattern. The opaque simulated iris pattern preferably includes at least one pattern element selectively colored and shaded to present a generally flat iris pattern appearance.
[0013] A number of further preferred and optional embodiments of the lenses of the present invention are described in greater detail below. For example, the opaque simulated iris pattern may include a plurality of (i.e., more than one) discontinuous pattern elements of different colors, which discontinuous pattern elements interlock to form a continuous and opaque pattern. One or more of the pattern element(s) may include an inner region that is more darkly shaded than adjacent portions of the pattern element. The opaque simulated iris pattern includes a cover layer of PVA overlying the pattern element(s).
[0014] In another aspect, the invention is a method of forming a contact lens. The method preferably includes applying ring-shaped aqueous solution of PVA to a mold; applying an opaque simulated iris pattern to a mold, casting a lens material in the mold to form a lens body, and transferring the opaque simulated iris pattern from the mold into the lens body.
[0015] These and other features and advantages of the present invention are described herein with reference to example embodiments shown in the appended drawing figures.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0016] [0016]FIG. 1 a is a cross-sectional side view of a contact lens according to a preferred form of the present invention.
[0017] [0017]FIG. 1 b is a plan view of the contact lens shown in FIG. 1.
[0018] [0018]FIG. 2 is a cross-sectional side view of a mold for forming a contact lens according to a preferred form of the present invention.
[0019] FIGS. 3 - 7 show cooperating pattern elements of a simulated iris pattern according to a preferred form of the present invention.
DETAILED DESCRIPTION
[0020] Referring now to the drawing figures, wherein like reference numerals represent like parts throughout, preferred forms of the present invention will now be described. FIGS. 1 a and 1 b show a contact lens 10 according to a preferred form of the present invention. The lens 10 may be a hard lens, a soft lens, an extended wear lens, or any other type of contact lens. The lens 10 typically comprises a lens body bounded by a concave inner or base surface 12 and a convex outer surface 14 . Preferably, the outer rim of the lens 10 contacts the limbal region of the wearer's eye and the center of the lens contacts the apex of the pupillary region of the cornea, providing a “three-point” fit with a layer of tears between the lens and the eye. The lens body is preferably formed of a substantially transparent, bio-compatible lens material. For example, the lens body may be formed of a polymerized hydroxyethylmethacrylate (HEMA)-based lens material, polysiloxanes, polyvinyl alcohol (PVA), hydrogels, homopolymers, copolymers, and/or other biocompatible transparent material(s). The lens body may or may not be tinted. The lens 10 may be configured to provide a desired degree of visual correction, or may be purely cosmetic.
[0021] The lens 10 preferably further comprises an opaque simulated iris pattern 20 applied to the lens body. In a preferred form, the simulated iris pattern 20 is molded into or otherwise applied to the base surface 12 of the lens body. Alternatively, the simulated iris pattern 20 is molded into or otherwise applied to the outer surface 14 . Application of the simulated iris pattern 20 to the base surface 12 improves comfort for most wearers, as the three-point fit prevents direct contact between the lens and the eye in the region of the simulated iris pattern, and as the eyelid does not contact the simulated iris pattern when the user blinks. Application of the simulated iris pattern 20 to the base surface also places the simulated iris pattern closer to the natural iris for a more realistic appearance. The simulated iris pattern is preferably applied to form an annular ring with its outer edge adjacent to the outer circumferential rim of the lens. The iris pattern has a width sufficient to obscure the natural iris when worn, and leaves a central optical zone 22 overlying the wearer's pupil unobscured.
[0022] The simulated iris pattern 20 preferably comprises ink comprising a pigment, dye or other colorant. The simulated iris pattern 20 can be virtually any color, and in preferred forms is a natural eye color such as blue, green, brown, or various combinations thereof. In alternate embodiments, the simulated iris pattern 20 is a non-natural eye color or color combination not typically occurring in humans. In further alternate embodiments, the simulated iris pattern 20 incorporates one or more patterns, logos, advertising or informational material, graphics or other designs. In still further embodiments, the simulated iris pattern 20 is a pattern that does not take the form of a natural iris, but rather is an unnatural iris pattern such as a cat-eye pattern or a geometric design. In a preferred form, the simulated iris pattern substantially entirely blocks color transmission from the underlying natural iris, which might inhibit the color-changing effect of the lens. In this manner, a simulated iris pattern 20 of a lighter color effectively masks a darker natural iris color.
[0023] The lens 10 further comprises a cover layer of PVA 30 overlying the simulated iris pattern 20 to substantially encapsulate the simulated iris pattern between the lens body and the cover layer 30 . Preferably, the cover layer 30 is applied as an aqueous solution, without colorant.
[0024] A significant problem associated with colored contact lenses is the leaching of color from lenses that use pigments as coloring agents. The present invention provides a protective PVA coating to the pigment layers. Preferably, the PVA layer is on the posterior side of the lens; thereby further assisting in retaining the contact lens on the cornea because of its adhesive and bonding property. The presence of a PVA layer increases the resistance to abrasion, tensile strength, elongation, and flexibility, which in some cases enhance the quality of a lens. The presence of a PVA layer also imparts increased resistance to protein deposition, a desired property for a contact lens.
[0025] Also, because the PVA film constitutes polymerizable components similar to that of the lens material the film bears good adhesion to the lens matrix due to the formation of an interpenetrating network with the lens. The medicinal properties of PVA further warrant the use of a layer of polyvinyl alcohol in our contact lenses. For example, a dilute solution of PVA can be used as a vehicle to apply therapeutic agents to the eye. The PVA forms a film over the cornea along with the drug. As PVA is retained on the cornea more effectively because of its adhesive properties the drug can stay in contact with the eye for an extended period before tears wash it away. Another scenario for therapeutic purpose would be the use of a drug that is released over time from an ophthalmic vehicle, the PVA film in this case. There are examples in the scientific literature of using a PVA solution to form a protective layer over the cornea after an eye surgery. The PVA layer has been shown to play a role in accelerating the rate of regeneration of the epithelial cells on the cornea after the surgery.
[0026] Specific drugs that may be used in accordance with the invention include, but are not limited to, methylcellulose, hydroxyethyl cellulose, alginic acid, a mixture of pilocarpine dispersed in methylcellulose and combinations of these polymers. In addition, the leens can include pilocarpine, timolol maleate, dexamethesone, antibiotics, sulpha drugs and, without limitation, any other drug that can be used in the eye in drop form.
[0027] The cover layer 30 provides a number of advantages, including: (i) preventing leaching of the colored ink forming the iris pattern out of the lens during use, storage and/or cleaning; (ii) adhering to the lens matrix to prevent peeling and separation of the lens; and (iii) encapsulating the pigment present within the colored ink of the iris pattern for safety and comfort of the user. Of course, those skilled in the art will recognize that the opaque iris pattern 20 may optionally be omitted, and the resulting lens will retain separate utility. It will also be understood that the depicted positions, relative sizes and shapes of the lens body, the simulated iris pattern 20 and the cover layer 30 are for reference and understanding only, and are not intended to be to scale or to approximate actual characteristics of the respective components.
[0028] The lens 10 of the present invention can be fabricated by casting in a mold, turning on a lathe, and/or by any appropriate lens-forming techniques. Likewise, the simulated iris pattern 20 and cover layer 30 can be applied into or onto the lens body by printing, stamping, or any appropriate application method. A preferred method of fabrication is described with particular reference to FIG. 2, and various examples are described with reference to FIGS. 3 - 15 . A male mold half 50 cooperates with a female mold half 52 to define a lens forming chamber 54 . It will be understood that the mold configuration depicted by FIG. 2 is by way of example only, and is not intended to represent actual mold geometry or necessarily be to scale. An aqueous PVA solution 60 and ink comprising colorant 62 are applied to one or both mold halves 50 , 52 to form the cover layer 30 and simulated iris pattern 20 respectively. In the depicted embodiment, the aqueous PVA solution 60 and ink comprising colorant 62 are applied to a convex face of the male mold half 50 , which face forms the concave base surface 12 of the lens. The aqueous PVA solution 60 is applied to the mold half, and the ink comprising colorant 62 is applied as one or more pattern elements over the PVA layer, whereby transfer of the PVA solution inks to the lens upon molding results in the PVA layer overlying and encapsulating the ink comprising colorant within the finished lens 10 . The lens 10 is preferably formed by casting lens material into the chamber 54 , and polymerizing and curing the material according to known lens molding techniques; preferably by exposure to UV radiation. In this manner, the iris pattern and cover layer become embedded into the lens itself to form an integral, unitary body, with the iris pattern and cover layer preferably bonded chemically and/or adhesively to the remainder of the lens.
[0029] In a preferred form of the present invention, the aqueous PVA solution 60 and ink comprising colorant 62 are applied to the mold 50 , 52 by transfer printing. The inks are applied to a cliché pattern, and then transferred from the cliché pattern to the mold via a transfer printing pad. The inks are subsequently transferred from the mold into the lens during the casting process. Preferably, the aqueous PVA solution 60 is first applied to the mold by transfer printing in a substantially continuous, solid annular ring pattern. It is preferred, but not required, to dry out the aqueous PVA solution before the iris pattern is applied thereto, leaving a layer of PVA upon the mold half. This is likely to happen within a few minutes through evaporation by air-drying. Alternatively, the solution can be dried using any one of known drying methods (e.g. heat). It is preferred that the PVA layer be less than 100 microns, preferably less tan 20 microns thick, and more preferably less than 15 microns. The most preferred thickness for the PVA layer is about 10 microns. The ink comprising colorant 62 is then applied over the PVA layer by transfer printing in one or more pattern elements to form the desired opaque simulated iris pattern 20 .
[0030] In preferred form, a plurality of different pattern elements combine to form the simulated iris pattern 20 . One or more of the different pattern elements preferably comprise a variegated or otherwise discontinuous pattern. More preferably, two or more of the plurality of different pattern elements are variegated or otherwise discontinuous, and cooperate or “interlock” in a complementary fashion, whereby the discontinuous pattern elements combine to form a continuous and fully opaque simulated iris pattern. The different pattern elements that combine to form the simulated iris pattern 20 preferably comprise different colors applied in a pattern to simulate the appearance of a natural iris. It will be understood that pattern elements of “different colors” include pattern elements of entirely distinct color (e.g., green and brown) and/or of different shades or gradations of the same color (e.g., dark blue and light blue). For example, different color sequences are described below with reference to a combination of cooperating pattern elements described with reference to FIGS. 3 - 7 . The additive effect of sequential layers of color gives a different and more natural hue to the final color of the iris pattern 20 . While certain of the individual pattern elements are discontinuous, they combine to form a continuous opaque pattern when applied in proper alignment and registration with one another. Similarly, any open spaces within the pattern of FIG. 6 or FIG. 7 are filled by the patterns of FIGS. 4 and/or 5 , when applied in proper registration. To compensate for any slight misalignment or mis-orientation of the individual pattern elements, it may be desirable to provide the pattern elements with a slight overlap at the pattern edges.
[0031] The present invention preferably further comprises providing the simulated iris pattern 20 with a selective color gradation and/or shading to produce the appearance of a flat iris. For example, when applied to a convex surface, darker colors in a pattern appear to recede, whereas lighter colors appear to come forward. Accordingly, by appropriately shading an inner region, or portions thereof, more darkly than an adjacent outer region, an iris pattern applied to a three-dimensional, convex surface appears generally two-dimensional or flat. In a preferred form of the present invention, the simulated iris pattern 20 comprises an annular ring having inner and outer edges. An inner region adjacent the inner edge is more darkly shaded than adjacent portions of the iris pattern. In this manner, the more central portions of the iris pattern nearer the apex of the convex lens surface appear to recede relative to the remainder of the iris pattern, generating the appearance of a generally flat iris, despite the convexity of the surface to which the lens pattern is applied. The iris pattern preferably comprises a substantially smooth color transition between the more darkly shaded inner region and less darkly shaded adjacent portions. Several example embodiments of the selective color gradation and/or shading of the present invention will be better understood with reference to the elements of the iris patterns shown respectively in FIGS. 3 - 7 , as detailed below.
[0032] PVA Solution Composition:
[0033] Polyvinyl alcohols are polymers of vinyl alcohol. As the latter cannot exist in free form, all polyvinyl alcohols have so far been manufactured by polymerization of vinyl acetate, which unlike vinyl alcohol, is stable. The polyvinyl acetate produced then undergoes alcoholysis. As the technical properties of polyvinyl alcohol depend in the first place on the molar mass and residual acetyl group content, industrial manufacturing processes are designed to ensure exact adherence to these parameters.
[0034] Although in practice water is virtually the only solvent used for PVA, a number of other suitable solvents or solvent mixtures do exist. While the slution is preferably free of solvents other than water, it is understood that other solvents may be used in place of, or in conjunction with water. Solutions up to 15% are considered suitable for use in the present invention. However, it is recognized that the optimal concentration will depend on the grade of PVA and the rate at which it is applied to the mold. Such concentrations will wither be apparent or easily determinable by those of skill in the art through routine experimentation. The presently preferred PVA solution is a 5% aqueous solution of MOLWIOL 20-98 PVA, commercially available from Clariant.
[0035] Polymers are identified, among other things, by their molar mass or degree of polymerization, the mean average weight M w or P w in relation to their molecule size.
[0036] In the case of polymers the molar mass values obtained always depend on the method of determination. Accordingly, comparisons are permissible only if the values have been obtained by the same methods under identical conditions. As used herein, the mean weights of the molar masses Mw indicate values determined by gel permeation chromatography (GPC) combined with static light scattering (absolute method) on re-acetylized specimens. The accuracy of given values is about ±15%. The P w for a given polymer is a calculated value derived from the Mw and the degree of hydrolysis.
[0037] For practical purposes an exact knowledge of the molar mass or the degree of polymerization is often only of secondary importance. For most applications it is quite sufficient to select the viscosity associated with these values for the (freshly produced) 4% aqueous solution and to know the degree of hydrolysis.
[0038] The mean average weight M w of various PVA grades can range from 14,000 to 205,000; and the P w ranges from 270 to 4300. Preferably, the M w of the PVA is about 125,000 and the P w is about 2800.
[0039] The procedure for making a 5% PVA solution is as follows:
[0040] A jacketed beaker, containing a spin-bar, was connected to a water bath circulator. The jacketed beaker was then loaded with 5 g of Clariant Mowiol 20-98 poly(vinyl alcohol). To this was added 95 g of USP water. The contents of the jacketed beaker were stirred manually using a spatula until all of the PVA particles were wet with water. The jacketed beaker was covered with a watch-glass to prevent water loss during heating. A magnetic stirrer was placed under the jacketed beaker and the contents were stirred. The circulating water bath was turned on and set to 98° C. The solution was allowed to stir for 2 hours at the desired temperature. Any particles that remain undissolved were dislodged from the walls of the beaker and allowed to dissolve. The beaker remain covereded with the watch glass. The solution was allowed to cool to room temperature while continuing to stir with the magnetic stirrer. Any condensate on the watch glass was drained back into the solution and the stirrer was turned off when the solution appeared homogeneous. The solution was filtered through a 5.0-μ hydrophilic filter, in desired aliquots, into Pyrex autoclavable bottles. The filled bottles were autoclaved and wrapped with aluminum foil to protect them from light exposure.
[0041] If a pharmaceutically active compound is desired to be included, it may be applied with the PVA layer or over the layer before the monomer is dispensed into the mold. One of skill in the art will recognize the need to ensure the compatibility of the pharmaceutically active compound and the lens components.
[0042] Ink Compositions:
[0043] The present invention further comprises various ink compositions for use in fabricating a lens as described above. Desirable properties of the ink composition include (i) adhesion to the mold material (rather than “beading up” and distorting the inked pattern); (ii) capability to accept one or more additional overlying ink layer(s) without an underlying layer dissolving, fracturing or otherwise significantly distorting; (iii) pattern-retaining compatibility with lens material whereby an inked pattern does not dissolve, fracture or significantly distort when lens material is cast into the mold; and (iv) ease of transfer of the patterns from the mold surface and incorporation and binding of inks into the lens material. With respect to (i) above, it should be noted that beading can be avoided by corona treating the molds or coating the molds with a primer. In a first example of an ink composition, the colored inks used to form the simulated iris pattern 20 preferably comprises a lens material-based ink composition, i.e., the ink should contain a component also contained in the lens polymer. For example, for lens bodies comprising hydroxyethylmethacrylate (HEMA)-based lens material, an ink composition comprising HEMA is preferably utilized:
Parent Ink Composition # 1: Wt. % Component: Weight (g) (w/Pigment) Isopropyl alcohol 42.5 g 57 (IPA, CAS # 67-63-0) Hydroxyethyl methacrylate 8.7 g 12 (HEMA, CAS # 868-77-9) Benzoin Methyl Ether 0.02 g (trace) (BME, CAS # 3524-62-7) Polyvinyl pyrrolidone 13.5 g 18 (PVP, CAS # 9009-39-8) Pigment (“daughter inks” - see 10 g 13 below)
[0044] This ink has been found well-suited for use with polypropylene mold surfaces. The ink is preferably formulated as follows: The individual components shown above were measured out in separate containers. The isopropyl alcohol was taken in a capped 250 mL glass container. BME was added to IPA and the mixture was stirred using a mechanical stirrer at 250 rpm. When all of the BME was dissolved (<2 minutes) HEMA was added and the stirring continued for about 2 minutes. PVP was added gradually in portions over a period of 5-10 minutes to avoid the formation of any clumps. It is suggested that the container be covered while stirring to minimize solvent evaporation. During the addition of PVP the speed of the stirrer was gradually increased to 450-500 rpm. In order to avoid any accidental breakage care should be taken that the rotating blade of the mechanical stirrer does not come in contact with the glass container. When the solution was homogeneous, the pigment was added in portions and the stirring continued for another 5-10 minutes to yield a colored ink of choice.
[0045] Alternative ink compositions are provided below:
Parent Ink Composition # 2: Wt. % Component: Weight (g) (w/Pigment) Vifilcon ™ A 10 g 20 (HEMA-based lens material) Pigment (“daughter inks” - see below) 2.5 g 5 Polyvinyl pyrrolidone 8.3 g 16 Isopropyl alcohol 30 g 59
[0046] This ink composition has been found well-suited for application to polypropylene mold surfaces upon which a PVA layer has been deposited.
Parent Ink Composition # 3: Wt. % Component: Weight (g) (w/Pigment) Vifilcon ™ A 10 g 25 (HEMA-based lens material) Polyvinyl pyrrolidone 4.1 g 10 Isopropyl alcohol 20 g 51 Pigment (“daughter inks” - see below) 5.5 g 14
[0047] This ink composition has been found well-suited for application to polycarbonate or polymethylmethacrylate mold surfaces upon which a PVA layer has been deposited.
[0048] A variety of “daughter” inks can be prepared based on any of the above parent ink compositions using different FDA-approved pigments or mixtures thereof. The pigments include (1) titanium (IV) oxide white, (2) phthalocyanine green, (3) iron oxide red, (4) phthalocyanine blue, (5) iron oxide yellow, (6) chromophtal violet, (7) chromium oxide green, and (8) iron oxide black. Example combinations of pigment components used in the preparation of daughter inks, and their approximate quantities, include:
Quantity (g) “Pink” Pigment Composition: titanium (IV) oxide white 100.0 g iron oxide red 100.0 g “Light Blue” Pigment Composition: titanium (IV) oxide white 158.8 g phthalocyanine blue 37.2 g iron oxide red 18.7 g “Black Blue 2” Pigment Composition: phthalocyanine blue 56.0 g iron oxide black 168.0 g “Black” Pigment Composition: iron oxide black 200.0 g “Pthalo Green-Yellow” Pigment Composition: iron oxide yellow 100.0 g phthalocyanine green 100.0 g “Pthalo Green-Black” Pigment Composition: iron oxide black 100.0 g phthalocyanine green 100.0 g “Chromium Green-Black” Pigment Composition: chromium oxide green 100.0 g iron oxide black 100.0 g “Yellow” Pigment Composition: iron oxide yellow 200.0 g “Medium Amber” Pigment Composition: iron oxide yellow 100.0 g iron oxide red 100.0 g “Medium Amber 2” Pigment Composition: iron oxide yellow 66.8 g iron oxide red 133.2 g “Dark Amber” Pigment Composition: iron oxide red 142.4 g phthalocyanine green 47.6 g chromophtal violet 10.5 g
[0049] Example Color Pattern Combinations:
[0050] Examples of color pattern combinations according to the present invention are set forth below with reference to the cliché patterns of FIGS. 3 - 15 , and the ink color compositions above. Pattern elements of the simulated iris pattern 20 are preferably applied to the mold via transfer printing in the specified sequence using different cliché patterns as depicted, in the ink color specified:
Cliché Pattern FIG. 6 or 7 Blue Color Sequence 1: Ink Color PVA Pink Light Blue Black Blue 2 Blue Color Sequence 2: Ink Color PVA Pink Light Blue Black Green Color Sequence 1: Ink Color PVA Pink Pthalo Green- Pthalo Green- Yellow Black Green Color Sequence 2: Ink Color PVA Chromium Yellow Pthalo Green- Green-Black Black Amber Color Sequence 1: Ink Color Clear Medium Medium Dark Amber Amber 2 Amber 2 Amber Color Sequence 2: Ink Color Clear Medium Medium Dark Amber Amber 2 Amber
[0051] As noted above, accurate alignment and orientation of the individual pattern elements results in the combination of pattern elements interlocking in a complementary manner to form a continuous and opaque iris pattern. Lens material is cast into the mold, thereby effecting transfer of the PVA layer and printed iris pattern from the mold into the cured lens body. The described color and cliché pattern combinations result in a natural and realistic iris appearance. Of course, it will be understood by those skilled in the art that a variety of other color combinations and cliché patterns are within the scope of the present invention as well.
[0052] While the invention has been described in its preferred forms, it will be readily apparent to those of ordinary skill in the art that many additions, modifications and deletions can be made thereto without departing from the spirit and scope of the invention. | A contact lens having a cover layer of polyvinyl alcohol and an opaque simulated iris pattern and an associated method of manufacture. The opaque simulated iris pattern obscures the underlying natural iris for superior color transformation, and provides enhanced cosmetic effect. | 1 |
BACKGROUND
[0001] The present invention relates to systems and methods for distribution of control information in a network server.
[0002] Distributed network services traditionally partition control operations into differentiated processes that each play separate roles in the processing of control and management functions. The SAF (service availability framework) partitions the hardware components for control operations into an active/standby pair of centralized system controller nodes and a variable set of control nodes. The SAF model also supports a 3-tier set of software processes that process the control functions across a distributed system; these processes are termed “director”, “node director”, and “agents” ( FIG. 1 ).
[0003] A two-tier process model is commonly used in Linux to manage distributed network services on a single node ( FIG. 2 ). Tier 1 includes inetd process registers on one or more TCP/IP ports, each port being tied to a separate network service. When a remote client connects to one of these ports, the inetd process then starts (in Tier 2) a separate network process that services all of the TCP/IP traffic for that socket. A configuration file specifies the TCP/IP port numbers that the inetd process registers in order to listen for inbound connections along with the corresponding server process to start when a connection is established to a port.
[0004] Modern messaging packages provide a messaging library used by clients to send and receive messages and a message broker that controls the distribution of messages between the messaging clients ( FIG. 3 ). Many messaging packages support both a topic publish/subscribe and a message queue service. In the publish/subscribe model, some clients subscribe to a topic for which they wish to receive messages, while other clients publish messages to the topic. The message broker routes messages from the publisher to any subscribers that have registered for the topic.
[0005] In each of the three presented networking services, a centralized architecture is used to distribute control and management functions. Within the SAF architecture, the active/standby system controller initiates all of the high level management functions for a SAF service ( FIG. 1 ). In the Linux inetd network service system programming model, the single inetd process on a host manages the initial TCP/IP network socket connections to the server ( FIG. 2 ). A message broker is a centralized messaging process that routes all of the messages associated with a topic within a cluster to each messaging client that has subscribed to the particular topic ( FIG. 3 ).
SUMMARY
[0006] A problem with the centralized architectures described above is that they cannot scale to systems that support thousands of nodes or clients because of centralized bottlenecks that constrain the rate of control or management functions that can be initiated within a distributed system.
[0007] Accordingly, the invention disclosed herein includes methods and systems for distributing control and management functions to achieve much better scalability than is possible with centralized control architectures. A system according to embodiments of this invention will be able to perform control functions across thousands of independent computer hosts in real-time. In some embodiments, the invention will be capable of processing thousands of control operations per second, with each control operation being processed by ten thousand or more hosts that are interconnected via a low latency network.
[0008] In one embodiment, a method of propagating an FCAPS operation through a plurality of servers including a configuration server connected on a network. The method includes the steps of: receiving, by the configuration server, an FCAPS operation; the configuration server selecting a server from the plurality of servers to be lead management aggregator; the configuration server transferring the FCAPS operation to the lead management aggregator; the lead management aggregator selecting a plurality of first deputy servers from the plurality of servers; and the lead management aggregator transferring the FCAPS operation to each of the first deputy servers.
[0009] In another embodiment, a system for propagating an FCAPS operation. The system includes a plurality of servers including a configuration server connected on a network to at least one client. The configuration server is configured to receive an FCAPS operation from the client, select a server from the plurality of servers to be lead management aggregator, and transfer the FCAPS operation to the lead management aggregator. The lead management aggregator is configured to select a plurality of first deputy servers from the plurality of servers, and transfer the FCAPS operation to each of the first deputy servers.
[0010] Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows a diagram of how the SAF (service availability framework) partitions the hardware components for control operations.
[0012] FIG. 2 shows a diagram of a two-tier process model as is commonly used in Linux to manage distributed network services on a single node.
[0013] FIG. 3 shows a diagram of a messaging package including a messaging library and a message broker.
[0014] FIG. 4 shows a diagram of a system for carrying out embodiments of the present invention.
[0015] FIG. 5 shows a diagram of a sharded system.
DETAILED DESCRIPTION
[0016] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
[0017] In various embodiments, the invention includes methods and systems for hierarchical distribution of control information in a massively scalable network server. The methods and systems are carried out using a plurality of servers that are connected using a network, of which various connections may be made in a wired or wireless manner and may be connected to the Internet. Each server may be implemented on a single standalone device or multiple servers may be implemented on a single physical device. Each server may include a controller, where one or more of the controllers includes a microprocessor, memory, and software (e.g. on a computer-readable medium including non-transient signals) that is configured to carry out the present invention. One or more servers may include input and output capabilities and may be connected to a user interface.
[0018] The invention partitions a plurality of hosts in a cluster to run two types of elements, namely the configuration database (confdb) servers and the network service servers. Clients connect to the configuration servers to perform network control and management functions, which are often referred to as FCAPS operations (Fault, Configuration, Accounting, Performance, and Security) in the networking industry; also referred to herein as a transaction. The protocols used to convey these FCAPS operations between a client and a configuration server are defined by Internet TCP/IP protocol standards and use TCP or UDP transport protocols to carry the network management packets. Network management protocols that are supported include, but are not limited to, NETCONF, SNMP, SSH CLI, and JSON/HTTP. Each network operation is load balanced from the client to one of the configuration servers using a standard TCP/IP load balancer.
[0019] FIG. 4 shows a diagram of a system for executing embodiments of the invention. One or more external management applications needing to execute an FCAPS operation identifies a CONFDB process through DNS discovery, thereby establishing a connection with a configuration database (CONFDB) server. The configuration database servers identify a lead aggregation component (also referred to as a lead management aggregator) in a service aggregation/service worker layer. Each of these components proceeds to execute the FCAPS operation as discussed below.
[0020] The configuration servers perform configuration operations that store and retrieve management information (e.g. set or modify a configuration element within the configuration database) and operational operations (or network service operation) that look up the running administrative state of network services running within the cluster (e.g. return information from the configuration database). The configuration database may be fully replicated across all of the configuration servers within a cluster. Alternatively, in some embodiments the database may be sharded, so that certain elements are processed by a subset of the configuration servers. When the configuration database is sharded, modifications to the configuration require locking the configuration databases within a shard so that atomic updates to configuration elements occur across the network elements that participate within an individual shard. As discussed further below, a shard refers to a subgroup of servers within a cluster which share a common property such as housing portions of a shared database. Increasing the number of shards reduces the percentage of network servers that are locked when a configuration item is updated, which in turn increases the transaction rate and scalability of network configuration services. Operational operations do not require locking and may or may not also be sharded across the configuration database servers.
[0021] When a configuration server receives a configuration change to the database, it propagates the change to all of the network servers that are managed by the configuration changeset (i.e. a set of changes that is treated as an indivisible group) that has been applied. Any one of the network servers in the cluster can handle configuration and administrative events for any network service that has been configured within the cluster. The configuration server dynamically selects one of these network servers to act as the “lead management aggregator” (LMA) for a particular network management operation. This selection can be made using a random selection, a load based selection, or a round-robin LRU (least-recently used) algorithm. The LMA uses a hierarchical distribution algorithm to distribute an FCAPS operation to the remaining network systems within the cluster. The LMA picks a small set (on the order of 2 to 5) of “management deputies” to apply the unfulfilled management operation. Each of this first line of deputies enrolls a small set (also on the order of 2 to 5) additional deputies to further propagate the management operation. In various embodiments, the number of deputies selected at each level can be different and can range from 2 to 5, 10, 20, 50, 100, or any other number of deputies. This pattern continues until every network server within the cluster has received and processed the management operation. A cluster for these purposes may include a set of addressable entities which may be processes, where some of the processes may be on the same server. In some embodiments, two or more of the addressable entities within a cluster may be in the same process. The cluster is separated into shards for particular transactions (see below). When an item is replicated across the cluster it is replicated only to those members of the cluster that have been denoted as participating in the shard to which the item belongs. In various embodiments, there is a separate framework including a controller which performs cluster management including tracking membership; the hierarchical control system uses this framework as input to determine which members participate within each shard. This framework is a dynamic entity that expands and contracts as servers enter and leave the system.
[0022] To show how quickly the operation can propagate, the following list shows the number of network servers that will process a management operation at each level of hierarchical distribution in a particular example. Assume that the LMA picks 5 primary deputies, and each of these 5 primary deputies pick 5 secondary deputies, and so on:
LMA: 1 network server 1st deputy level: 1 LMA+5 1st level deputies=6 network servers 2nd deputy level: 1+5+5*5=31 network servers 3rd deputy level: 1+5+5*5+5*5*5=156 network servers 4th deputy level: 1+5+5*5+5*5*5+5*5*5*5=781 network servers
[0028] FIG. 5 shows a diagram of a sharded system. The diagram in FIG. 5 shows a cluster of thirty servers (although the cluster may have any number) labeled A-Q and 1-13. In this particular example, servers 1-13 are a shard within the cluster which are used for a specific transaction. A transaction can include configuration operations and operational operations as discussed above. Any subgroup of servers may be placed into a shard for a given transaction and the servers within the cluster and/or shard do not have to be in the same physical location. In this transaction, the configuration server selects one of the servers within the shard to be the primary deputy. The primary deputy receives the transaction and subsequently selects several other servers from the shard (three servers in this example) to be secondary deputies. Each of the secondary deputies in turn recursively selects a group of third level deputies, etc. until all of the servers within the shard have been recruited. As seen in FIG. 5 , only three levels are needed to recruit all thirteen of the servers in the shard, each of which is required to recruit at most three other servers. As discussed this procedure can be used with larger numbers of servers, each of which may recruit a larger number of deputies at each level, to propagate a transaction through a network of servers with a high degree of efficiency.
[0029] In various embodiments, some or all of the above-described activities ascribed to the LMA, the primary deputy, and the secondary and other deputies may be mediated by calls to a distributed transaction system (DTS) library ( FIG. 5 ). In such embodiments, the DTS library may be used by FCAPS (e.g. to initiate the distribution of transactions) and/or by the LMA or deputies (e.g. to propagate the distribution of transactions).
[0030] For configuration operations, the LMA processes the configuration and if successful, it then propagates the configuration operation to the next set of deputies using the procedure described above. If an error is present in the configuration, then the LMA will not propagate the configuration change any further within the cluster. Once the LMA propagates the configuration change to its first line of deputies, these deputies process the configuration and distribute the configuration change to the second line of deputies. Any network servers other than the LMA that cannot successfully apply the configuration change are not consistent with the cluster and remove themselves from the group until they can resynchronize their configuration database with the group. In various embodiments, one or more servers are maintained as ‘authoritative sources’ which are used as a reference that can be used to resynchronize the configuration database of a network server.
[0031] When a configuration change is applied, there are certain cases that may result in an error, indicating that the configuration change cannot be successfully applied. These cases typically occur when references to other entities result in an error. For example, if an IP address is assigned to an interface and the interface does not exist, that would be an error. If every other member of the cluster could apply the change because that interface is visible to them and the singular member could not, then the singular member would be removed from the cluster because it is inconsistent with the rest of the members in the cluster.
[0032] For network service operations, the LMA distributes the operational command to the first set of deputies and waits for a response. Each deputy in turn distributes the operational command to the next set of deputies until the bottom level of nodes have been contacted. These nodes then process the operational command and return the data to the deputies that contacted them. The LMA and each deputy aggregate the responses into a single operational response that they return to the caller that invoked them. The configuration server that initiated the operational operation receives an aggregated operational response from the LMA.
[0033] Various features and advantages of the invention are set forth in the following claims. | A method of propagating an FCAPS operation through a plurality of servers including a configuration server connected on a network. The method includes the steps of: receiving, by the configuration server, an FCAPS operation; the configuration server selecting a server from the plurality of servers to be lead management aggregator; the configuration server transferring the FCAPS operation to the lead management aggregator; the lead management aggregator selecting a plurality of first deputy servers from the plurality of servers; and the lead management aggregator transferring the FCAPS operation to each of the first deputy servers. | 7 |
DEDICATORY CLAUSE
The invention described herein may be manufactured, used and licensed by or for the Government for governmental purposes without the payment to me of any royalties thereon.
BACKGROUND OF THE INVENTION
A typical turbo shaft engine has a mechanical torque sensing device that drives a cockpit indicator so that the pilot or operator can know the power output of the engine. Torque is a critical parameter monitored by pilots and engine operators to control the aircraft or other engines and prevent damage to other drive train components. Most torque meters actually measure the twist in a drive shaft within the engine for torque indication. The accuracy of these torque measurements is affected by the shaft material properties, the temperature of the shaft, the frictional components that support the shaft and the torsional creep of the shaft itself. In addition, deficiencies in the accuracy, resolution, environmental response of the transducer, signal conditioning and computations have a large effect on the measurement accuracy. The cumulative effect of such deficiencies often is a torque indication that is unsatisfactory for smooth, safe and accurately reliable engine control.
One of the means to improve torque accuracy involves characterizing each torque shaft individually against a reference torque measurement system by entering the shaft-specific data into an electronic engine controller. With this shaft-specific data, the electronic engine controller can correct torque sensor signals to account for shaft material properties and operating conditions. Work has been done on improving the materials used for building torque shafts to achieve more uniform material characteristics. Low friction sleeves and bushings have been installed between reference shafts and load-carrying shafts to improve torque meter performance.
Another means for achieving accurate torque reading utilizes algorithms developed to adjust the torque readings to account for temperature variations in the torque meter shaft. Because a typical turbine engine is used to produce varying power output, the internal temperature of the engine changes constantly. This change in temperature causes a change in temperature of the torque meter. As is well-known, when a metal is subjected to changes in temperature, its material properties change which allows the metal to twist a different amount in response to the same applied torque. Corrective algorithms neutralize the effects of the temperature variations. But the use of corrective algorithms necessitates the added complexity of taking shaft temperature measurement or generating a synthesized (i.e. approximated) shaft temperatures and, as a result, reduces system reliability.
In providing torque indication for a helicopter engine, a single pressure tap in front of the power turbine has been used. But this positioning of the single tap cannot account for exhaust system losses or the effects of the dynamics of the helicopter, such as changes in the helicopter speed and the flight attitude that affect the backpressure to the engine. All these aspects tend to reduce the accuracy of the torque measurements.
Because of the general unreliability of many torque sensors, synthesized torque signals are often used by engine control systems as a backup torque signal. Synthesized torque signals are generated by using other engine parameters such as compressor discharge pressure, gas generator speed, turbine inlet temperature or combinations of these and pre-established engine characteristics. Such synthesized torque signals can give an approximate engine torque indications but are plagued with inaccuracies due to off-design operation, engine deterioration from wear and tear and even bleed air extraction in many turbine applications.
SUMMARY OF THE INVENTION
In applicant's Differential-Pressure Torque Measurement System, the torque signal is generated from a differential gas pressure measured across the power turbine. The gas pressure differential is measured by using two pressure taps, one tap positioned on either side of the power turbine. The first tap takes the pressure reading of the expanding gas as the gas travels from the gas-generating turbine to the power turbine of the engine while the second tap takes the pressure reading of the gas as it escapes the engine through the exhaust port. The two pressure readings from the two taps are then input to a differential pressure sensor which determines the differential between the two pressure readings. The pressure differential is, in turn, input to a processor which processes it in a pre-determined fashion along with the rotational speed signal of the power turbine, the initial pressure and the initial temperature measurements of the air as the air is inlet into the engine. The results of the processing are various engine parameter indications including the torque.
Unlike torque-reading methods that use only a single pressure tap, either in front of the power turbine or in the pre-combustion stage, applicant's differential pressure system compensates for any static and dynamic effects caused by the engine exhaust system and for any variation in power turbine speeds from the design operating speed. By using the pressure differential across the power turbine, the torque signal generated is consistent and accurate, because the power turbine deteriorates very little over the life of the turbine engine compared to other components such as the compressor and gas-generating turbine. Thus, the differential pressure system provides a simple, low-cost, lightweight, easy-to-install and accurate torque measurement system that can be used on helicopters, turboshaft-driven fixed-wing aircraft and industrial gas turbine engines.
DESCRIPTION OF THE DRAWING
FIG. 1 is a diagram of tire preferred embodiment of the Turbine Engine Differential-Pressure Torque Measurement System.
FIG. 2 details the process performed by the processor to generate engine parameters.
FIG. 3 is a graphic depiction of a representative engine characteristic for the process detailed in FIG. 2 .
FIG. 4 shows an alternate, simpler process performed by the processor to generate engine parameters.
FIG. 5 is a graphic depiction of a representative engine characteristic for the process detailed in FIG. 4 .
FIG. 6 is a diagram of yet another alternate process performed by the processor, taking into consideration differential pressure across the exhaust system.
FIG. 7 is a graphic depiction of a representative engine characteristic for the process detailed in FIG. 6 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing wherein like numbers represent like parts in each of the several figures, solid lines with arrowheads indicate signal paths and broken lines with arrowheads indicate optional signals and paths, the Turbine Engine Differential-Pressure Torque Measurement System is explained in detail.
To facilitate the description of the structure and operation of the Torque Measurement System, the following terms and definitions are used:
DP 1 =P 4 -P 5 : first differential pressure measured, in psi, with differential pressure sensor 27 . DP 2 =P 5 -P 0 : second differential pressure, in psia, across the exhaust system. P 0 : ambient air pressure, in psia, measured with ambient air pressure sensor 28 . P 1 : initial pressure of the inlet air measured, in psia, with pressure sensor 16 . P 4 : first pressure reading. P 5 : second pressure reading.
Delta = P1 14.696 :
correction factor where 14.696 is in units of psia and is a normalization constant corresponding to standard day sea level pressure.
NP: rotational speed signal, in RPM or %, measured with speed sensor indicating the rotational speed of power turbine 20 and output shaft 21 , where NP=100% represents a specific, pre-determined rotational speed. The conversion from RPM to % rotational speed is engine model-specific and is established by the engine manufacturer. T 1 : initial temperature of inlet air measured, in degrees Rankine (Degree R), with temperature sensor 15 .
Theta = T1 518.7 :
correction factor where 518.7 is in R and is a normalization constant corresponding to standard day sea level ambient air temperature.
NPC = NP theta :
NP corrected to T 1 .
DP1C = DP1 Delta :
DP 1 corrected to pressure P 1 .
PR1 = DP2 P5 :
pressure ratio 1 , the backpressure to the engine caused by the engine exhaust system
SHP: power delivered from the engine to the load (i.e. any device that is powered by the engine), typically in units of shaft horsepower.
SHPC = SHP ( Delta ) ( Theta ) 0.50 :
SHP corrected to P 1 and T 1 .
Q = ( SHP ) ( 5252.1 ) NP :
torque delivered from the engine to the load, typically in units of foot-pounds (ft-lbs.).
S 1 : referring collectively to SHP, SHPC and Q. 5252.1: a standard conversion constant used in converting shaft horsepower to torque, Q, based on the rotational speed of the shaft, NP.
FIG. 1 illustrates the Differential-Pressure Torque Measurement System which operates in conjunction with a typical gas turbine engine 10 that has a shaft ouput 21 and provides power to load 40 that is driven by free power turbine 20 . Power turbine 20 is free because it does not drive compressor 11 , even if it is physically connected to the compressor by, say, bearings. Load 40 can be any controllable device such as an aircraft gearbox that transmits power to rotorblades of a helicopter or the propeller of a propeller-driven fixed-wing aircraft. The device may also be an electrical generator or any other industrial hardware.
In operation of the Differential-Pressure Torque Measurement System, outside air is let into compressor 11 through inlet 18 . Adjacent to the inlet are temperature sensor 15 that provides the inlet air temperature measurement T 1 and pressure sensor 16 that provides the inlet air pressure measurement P 1 , both measurements being input to processor 50 . The inlet air is compressed by compressor 11 and forwarded to combustor 14 which communicates with the compressor and where fuel is added and ignited. The expanding gasses that result from this combustion turn gas-generating turbine 12 which, in turn, drives connecting shaft 13 . Since the connecting shaft connects the gas-generating turbine and the compressor, the action of driving the connecting shaft also drives the compressor. Thus, the compression and combustion cycle is maintained as long as inlet air and fuel are combined at an appropriate ratio to sustain combustion.
The excess expanding gas that remains after the the requirement for compression-combustion sustainment is met leaves gas-generating turbine 12 and enters power turbine 20 . On its way, the gas passes first pressure tap 22 which provides first pressure reading P 4 to differential pressure sensor 27 . Meanwhile, in response to the incoming expanding gas, power turbine 20 turns output shaft 21 to drive load 40 . The rotational speed of the power turbine is measured by speed sensor 25 which provides speed signal NP and inputs it directly to processor 50 . After the expanding gas departs power turbine 20 , it exits engine 10 through exhaust port 26 and duct 30 . As the gas exits, its pressure is read by second pressure tap 24 , thus providing a second pressure reading P 5 . P 5 is input to differential pressure sensor 27 and may further be input to processor 50 . In response to P 4 and P 5 inputs, the differential pressure sensor produces first differential pressure signal DP 1 and inputs DP 1 to processor 50 .
FIG. 2 details the process executed by processor 50 to generate engine output parameters S 1 . The processor can be a subset of an electronic engine controller, a data acquisition system, a facility/system controller/monitor or even a stand-alone electronic device. It may be comprised of analog circuitry, digital circuitry or a combination of both types of circuitry and may be configured in any fashion that may occur to one skilled in the art as long as it is sufficient to perform the process illustrated in FIG. 2 .
As represented by FIG. 2 , processor 50 comprises a plurality of dividers and product blocks, as well as a means for calculating SHPC, the corrected shaft horsepower value. In operation of the processor, Delta is produced by first divider 121 from the initial pressure measurement P 1 of the inlet air as the numerator and first pre-determined normalization constant, 14.696 psia, as the denominator. The Delta value is input to second divider 122 and second product block 126 . In turn, second divider 122 utilizes first differential pressure signal, DP 1 , as the numerator and the Delta as the denominator and produces DP 1 C, corrected differential pressure signal, and inputs this result to calculating means 124 . Third divider 123 utilizes the initial temperature measurement T 1 of the inlet air as the numerator and second pre-determined normalization constant, 518.67 R, as the denominator to produce Theta value. The Theta value is input to first product block 125 and second product block 126 . Both the Delta and Theta values are standard correction factors used to correct or refer engine parameter data to a pre-defined condition: in this case, sea level standard atmospheric day conditions of 14.696 psia and 59 degree F. or 518.67 degree R. However, depending on the particular environment in which the Turbine Engine Differential-Pressure Torque Measurement System is to be used, different pre-determined normalization constants that correspond to that particular environment should be used to calculate the Delta and Theta values.
The Theta value is used, along with NP (the NP being input simultaneously to the first product block 125 and third product block 127 ), by the first product block to produce NPC according to a formula above mentioned. NPC, in turn, is input to calculating means 124 . The calculating means may be a function, either a look-up table or a mathematical equation, that generates the engine parameter SHPC from DP 1 C and NPC. FIG. 3 graphically depicts the function, showing the SHPC along the vertical axis as a function of DP 1 C along the horizontal axis. A collection of SHPC v. DP 1 C curves is shown in terms of NPC. The value of SHPC is input to second product block 126 .
SHP is yielded by second product block 126 as a product of the equation, (SHPC)(Delta)((Theta) 0.50 ). This equation represents the typical conversion from SHPC to SHP used by engine manufacturers. However, some variations can and do exist. Some engine manufacturers adjust the exponent of Theta to represent the conversion more accurately for their specific engine. For example, a manufacturer may use SHP=(SHPC)(Delta)((Theta) 0.537 ) for its conversion. By adjusting the exponent of Theta, the manufacturer can more accurately refer its engine's performance data to a wider range of ambient conditions for a specific model of engine. The equation for a specific engine model may vary thusly, but the process remains the same as long as the engine model-specific equation is inserted in second product block 126 . The value of SHP is input to third product block 127 .
The third product block outputs the torque value, Q, of engine 10 according to a formula set forth above. The output, S 1 , of processor 50 enables the operator of load 40 to gauge the capacities of the engine accurately and consequently maintain a precise control of the engine for optimum support of the controllable device.
An alternate, simpler process that can replace the process illustrated in FIG. 2 is shown in FIG. 4 . This alternate process is identical to that depicted in FIG. 2 except that it eliminates first product block 125 while still generating SHPC, SHP and Q. The alternate process can be used on engines that run at a constant NP or have torque characteristics insensitive to the allowable changes in NP or on engines where the desired system accuracy can be achieved without compensating for variations in the rotating speed of power turbine 20 . As seen in FIG. 5 , the alternate process reduces the amount of upfront engine characterization data required. Like the graph in FIG. 3 , the graph in FIG. 5 depicts SHPC along the vertical axis as a function of DP 1 C along the horizontal axis. A single curve of SHPC v. DP 1 C is shown.
FIG. 6 shows yet another alternate process that may be performed by processor 50 to generate the engine parameters. This second alternate process is also identical to the process described in FIG. 2 except for the adder 141 and fourth divider 142 . The adder combines P 0 and P 5 to produce second differential pressure signal, DP 2 , which, then, is input to the fourth divider. The fourth divider utilizes DP 2 as the numerator and P 5 as the denominator to provide PR 1 . PR 1 is input to calculating means 124 wherein it is processed along with other inputs to produce SHPC. This embodiment may be used on engines that are run at variable NP speeds and when the engine is further susceptible to a variation in exhaust backpressure. When an engine is installed in an aircraft or put to an application with a complex exhaust system, the exhaust backpressure can vary with engine power output. A typical case is an aircraft fitted with engine exhaust infrared suppressors. The variation in backpressure changes the delta pressure across the power turbine and can reduce the accuracy of the embodiments depicted in FIGS. 2 and 4 . The embodiment of FIG. 6 compensates for the changes in backpressure at the exit of the power turbine. FIG. 7 shows a collection of SHPC v. DP 1 PC curves in terms of NPC and a given percent backpressure.
Although a particular embodiment and form of this invention has been illustrated, it is apparent that various modifications and embodiments of the invention may be made by those skilled in the art without departing from the scope and spirit of the foregoing disclosure. Accordingly, the scope of the invention should be limited only by the claims appended hereto. | Applicant's Differential-Pressure Torque Measurement System generates the torque signal from a differential gas pressure measured across the power turbine. The gas pressure differential is measured by using two pressure taps, the first tap taking the pressure reading of the expanding gas as the gas travels from the gas-generating turbine to the power turbine of the engine and the second tap taking the pressure reading of the gas as it escapes the engine through the exhaust port. The differential between the two pressure readings is determined. The pressure differential is then input to a processor which processes it in a pre-determined fashion along with the rotational speed signal of the power turbine, initial pressure and the temperature measurements of the air as the air is initially inlet into the engine. The result of the processing are various engine parameter indications including the torque. | 5 |
BACKGROUND
There are many various types of ink stamping devices available for particular applications in industry including relatively expensive and sophisticated printers and the like.
In many assembly line type manufacturing applications various parts or subassemblies of parts produced in high volume require various repetitive indicia or markings, such as part identity numbers and the like.
One of the problems long encountered in such manufacturing lines is the lack of a highly reliable, adaptable, and yet reasonable cost contact ink stamping apparatus which is capable of high volume production. A further problem in seeking a satisfactory printer of this type is that the configuration and line of motion of the ink stamping device does not readily accomodate the often times crowded condition of the assembly line operation to permit easy installation of the stamping device in an already existing production line at an appropriate location.
Prior to the present invention, there has not been available a low profile printer having a horizontal piston stroke length which also provides a vertical stamping stroke in a relatively simple and inexpensive manner.
SUMMARY OF INVENTION
The present invention relates generally to high speed, high volume contact ink stamping devices which are particularly adaptable to various high volume production lines of parts and subassemblies. In particular, the present invention relates to a vertically compact or low profile ink stamping device which incorporates a horizontally disposed piston to move the stamping platen between horizontally displaced ink filling and ink stamping position as well as means to effect a vertical stroke to the platen at each such position.
The ink stamping device of the present invention also incorporates an easy fill ink supply and a readily removable ink stamping platen to provide for very effective and efficient adaption to changing indicia. The low profile configuration and the one piston assembly are also designed for economical manufacture and is readily adaptable for installation in a variety of locations within a given production line.
The ink stamping assembly is mounted to a slide member which in turn is mounted within a carriage member incorporating a stop limiting horizontal travel of the slide plate. The slide member within the carriage is provided with an opening for receiving an upper portion of a stem connected to a stamping platen. The opening in the slide member includes inclined surfaces which cooperate with the upper end of the stem to effect transfer of the horizontal motion of the drive piston into vertical motion of the ink platen at the ink supply station and at the stamping station.
OBJECTS
It is therefore an object of the present invention to provide an ink stamping apparatus particularly useful for high volume, high speed applications which incorporates a vertically compact configuration.
It is another object of the present invention to provide an apparatus of the type described which incorporate a single horizontal piston stroke to effect both a horizontal and a vertical displacement of the ink stamping platen.
It is another object of the present invention to provide an apparatus of the type described which is readily adaptable to changing the ink stamping platen in a very easy manner.
It is a further object of the present invention to provide an apparatus of the type described which is very reliable and easily maintained and yet is incorporated in a simple and economical structure.
Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred form of embodiment of the invention is clearly shown.
IN THE DRAWINGS
FIG. 1 is a front elevational view of an automatic ink stamping apparatus constructed in accordance with the present invention;
FIG. 2 is a top plan view of the apparatus shown in FIG. 1;
FIG. 3 is a front elevational view similar to that of FIG. 1 illustrating the ink stamping platen assembly horizontally displaced between the inking supply station and the stamping station;
FIG. 4 is a front elevational view similar to FIG. 1 illustrating the ink stamping platen positioned at the ink stamping station;
FIG. 5 is a side sectional view of the apparatus of the preceding Figures, the section being taken along line 5--5 in FIG. 2; and
FIG. 6 is a partial side elevational view in section of a portion of the apparatus shown in FIG. 1, the section being taken along line 6--6 in FIG. 1.
DETAILED DESCRIPTION
FIGS. 1 and 2 illustrate an ink stamping apparatus constructed in accordance to the present invention and includes a mounting base means 20 which may be fixed by any conventional means to a support base, not shown, adapted to any particular application. Base means 20 includes a foot portion 22 and a vertical frame portion 24.
As best seen in FIG. 5, a vertically extending support frame 26 is movably mounted to vertical frame portion 24 by means of a threaded support member 28 and a pair of bolts 30. Bolts 30 are mounted through a plate 32 and each extend through parallel slots provided in frame portion 24 such that bolts 30 frictionally engage support frame 26 when tightened.
Threaded support member 28 is received in a threaded bore 34 in the bottom of frame 26 and at the opposite end in a bore 36 in support member 38 and carries a nut 40 which provides a means to raise and lower vertical support frame 26 relative to foot portion 22 of base means 20.
A conventional piston assembly, indicated generally at 42 is conventionally mounted to the upper end of vertical support frame 26 with piston rod 44 extending through a bore 46.
An ink supply station, indicating generally at 48, is mounted to vertical support frame 26 by means of a L-shaped mounting bracket 50 and bolts 52 which are disposed through one of a pair of vertically extending slots provided in bracket 50 for frictional engagement with support frame 26.
Mounting bracket 50 includes a horizontal arm supporting the ink supply pad and reservoir assembly indicated generally at 54.
The assembly 54 includes an outer housing 56, a movably mounted base means provided with a recess functioning as ink reservoir 58 which supports a conventional absorbent ink pad 60.
A threaded adjustment member 65 and ink pad 60 provides adjustment of ink pad reservoir 58 in relation to stamped pad 100 and is locked in position with locking screws 63.
As best seen in FIGS. 1 and 2, ink reservoir 58 provided within housing 56 is communicated in a conventional manner to a source of ink contained in a bottle 59. Preferably, a conventional conduit 61 in the form of an elbow and threaded connector attached to the bottle opening is provided for easy access to change the bottle supply or refill it. Further, it has been found desirable to employ a wick extending from reservoir 58 through the conduit 61 and into the bottle 59 to provide a supply of ink to reservoir 58 in an efficient and reliable manner.
Specifically referring to FIGS. 1, 5 and 6, a horizontal disposed housing forms a rail or guide means for the stamping assembly and includes side frame members 62 and end support and stop member 64.
Side frame members 62 are connected at one end to vertical support member 26 by conventional bolts such as 66. End member 64 is conventionally bolted to each side member 62. Each side member 62 is provided with a laterally extending recess 68 which forms a guide track to receive bearing members 72 provided on a sliding T-shaped carriage assembly indicated generally at 70.
A slide block 74 of generally rectangular configuration is threaded fixed to the inner end of piston rod 44 and is slideably received within a mating opening or channel 76 provided in T-shaped carriage 70.
A vertical channel 78 is also provided in carriage assembly 70 and slideably receives the stem or plunger portion 80 which in turn carries the ink stamping platen assembly 82 on its lower end.
Slide block 74 is provided with an opening 85 extending approximately half way through block 74 which is provided with inclined walls 83. The upper end of opening 85 includes a notch 81.
The upper end of stem 80 is provided with a recessed head portion 84 and a pair of inclined walls, such as at 90. A pin 86, carrying a bearing member 88, is mounted through head portion 84 with the bearing 88 extending outward in the recessed portion thereof. Preferably a very slight angular recessed portion is provided on the face of head portion 84 to provide a predetermined clearance to permit the inclined wall surfaces 83 to ride upon the bearing member 88 when head portion 84 is disposed in assembled fashion with pin 86 and bearing 88 extending into opening 83. However, the important consideration is to provide for the inclined plane effect between the walls 83 and bearing 88 on recessed head of stem 80 as will be described in detail later herein.
Stem 80 also includes a vertically extending recess 92 for housing a compression spring 94. The lower end of recess 92 includes an opening to receive a stop pin 96 provided on carriage member 70 which engages the lower end of spring 94 to cause stem 80 to be biased upwardly into channel 78 and toward notch 81.
The upper opening of channel 78 is covered by a plate 93 to prevent inadvertent debris or the like from falling into the opening. Also, optionally, a protective top cover may be provided to enclose the open area between side plates 62 and carriage member 70 for safety purposes.
Referring again to FIG. 5, stem 80 is shown in its depressed position as bearing member rode downwardly along the inclined wall on the right of slide block 74 as viewed in FIG. 5, and piston rod 44 has reached its fully retracted position. Spring 92 is depressed downwardly againt pin 96 and stem 80 is biased upwardly.
Prior to piston rod 44 reaching its fully retracted position, the left end of carriage member 70, engages the face of a stop plate 98 fastened to support frame 26, preventing further travel of carriage 70. Since slide block 74 fully slides within channel 76 of carriage 70, it continues to the left and causes stem 80 to be depressed downwardly upon the forced engagement between the inclined wall of slide block 74 and bearing member 88 on pin 86 which is carried on stem 80.
Upon the return stroke of the piston rod 44, slide block 74 slides within channel 76 to the right and the upward bias of spring 94 causes stem 80 to move upwardly as bearing member 88 slides upwardly along the same inclined wall of block 74.
When the upper end of head portion 84 of stem 80 has reached the midpoint of notch 81, continued movement of piston rod 44 to the right, causes carriage member 70, stem 80 and slide block 74 to move to the right, as illustrated in FIG. 3.
At a predetermined position along the extended piston rod stroke, to the right as viewed in FIG. 5, the right end of carriage 70 engages the end closure plate 64 to prevent further movement of carriage 70. This horizontal distance is pre-selected to define the stamping station. As piston rod 44 continues to complete its fully extended stroke, slide block 74, carried on the end of rod 44 continues to move to the right and bearing member 88 engages the left inclined wall surface 83 provided in block 74 which forces stem 80 downwardly against the bias of spring 94. Further horizontal travel of stem 80 is prevented since carriage member 70 is held stationary against further movement by engagement with end plate 64.
The stamping platen carrying the removably mounted stamp pad 100, is then caused to forcefully engage the workpiece as shown in FIG. 4. The work piece surface to be stamped is positioned at a predetermined distance from the platen related to a distance less than the full downward stroke of stem 80. Upon the return stroke of rod 44, slide block 74 moves to the left and stem 80 rises due to the bias of spring 94 as bearing member 88 travels along the same left inclined wall surface 83.
As the head portion 84 of stem 80 again reaches the centered position at notch 81, carriage member 70 is pulled horizontally to the left toward the ink supply station wherein stem 80 is depressed downwardly into engagement with inking pad 56 at the ink supply station. Then another piston stroke actuates the repetitive of the cycle as described.
From the foregoing description, it should be readily apparent that the present invention provides a simplified ink stamping apparatus which efficiently moves the stamping platen horizontally along a path between an ink supply station and an ink stamping station using only one horizontally disposed piston which also provides the force to create downward vertical movement of the platen at each station.
In this manner, expense in construction is saved since only one piston and cylinder is required and maintenance and replacement cost is lower than in prior art types which employ additional pistons for the vertical stroke of the ink stamping and supply step.
Also, the use of one horizontally disposed piston in the construction of the present invention permits the apparatus to be constructed with a relatively low vertical profile to more easily fit into assembly or production lines which have limited head room.
The construction of the carriage, slide block and guide rails 68 is also relatively easy and inexpensive to manufacture and requires little maintenance to provide for efficient and reliable service for high volume production. | An automatic contact ink stamping apparatus for printing predetermined indicia particularly adapted for marking assembly lines parts or other objects which is characterized by a dual acting piston stroke assembly which is operatively attached to a stamp platen to move the platen between an inking position adjacent to an ink supply and a stamping position adjacent to the work piece. The stamp platen is mounted to a horizontal slide assembly which includes an opening having a pair of inclined walls. A vertically extending stem connected to the stamp platen is provided with bearing surfaces which cooperate with the inclined walls of the slide assembly and a cooperating carriage member to transfer a terminal portion of the horizontal stroke length of the piston into vertical displacement of the stamp platen at the respective ink supply and ink stamping stations. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electrophotographic recording apparatus which records externally-supplied electical signal information on a recording sheet as of plain paper by electrophotographic processing, and more particularly to a method of controlling the toner concentration of developer so as to maintain constant the stable quality of an image produced on the recording paper.
2. Prior Art of the Invention
In apparatus such as electrophotographic printers, compound information recording apparatus, facsimile machines, and the like which record external information by an electrophotographic process, a visible image recorded on a sheet of recording paper is obtained by developing externally-supplied information formed on a photosensitive member with a developer consisting of toner particles and carrier particles. In order to maintain the quality of the recorded image and, particularly a constant density of the image, the concentration of the developer (i.e. of the toner thereof) must be kept substantially constant. Various methods of detecting such toner concentration have heretofore been suggested, such, for example, as an optical method by which the amount of light transmitted through a transparent disc to which toner is attached; is converted to an electric current an electrical method by which the variation of electric current flowing through the developer is measuring (taking advantage of the insulation characteristics of the toner) and a magnetic method by which the magnetic permeability of the developer is measured (based upon known variation thereof as the toner concentration in the developer varies). On the other hand, insofar as controlling the toner concentration in an information recording apparatus utilizing an electrophotographic process, only a method similar to the aforementioned optical method is understood to have been suggested.
The practice of such any of such conventional toner concentration detecting methods, requires a special detecting element and detecting circuit requiring space therefor within the recording apparatus, thus increasing the size and cost of such apparatus.
SUMMARY OF THE INVENTION
In accordance with the present invention, an information recording apparatus utilizes an optical scanning means or electric discharge means for recording externally-supplied information which is, for example, temporarily stored in a memory of an electronic microcomputer. An electrostatic latent image of a reference density or concentration signal is formed on a photosensitive member (or a member capable of retaining an electrostatic charge) prior or subsequent to the formation of an external information signal latent image, and is thereafter developed with the development of the external information signal image to form a visual reference density region. The density this developed region is then detected by photoelectric means, from which detection control of the toner concentration is effected. According to the present invention, the requirement of conventional detecting methods for special detecting elements or detecting circuits is unnecessary because the method of the invention is capable of providing both the reference density signal in the form of an electric signal, and a reference density region by utilizing the electrophotographic process normally used in the processing of information images. The present invention, however, merely requires photoelectric means for detecting the density of the reference density region. Consequently, the detecting means itself may be of a very simmple construction, is economically advantageous, and is further able to provide the reference density signal in the form of an electric signal, thus permitting the formation of a reference density region free of the so-called "edge effect" whereby the edge portion of an electrophotographic image edge portion is deeply darkened with respect to the image interior which is notably lighter or washy.
An embodiment of the present invention is described hereinafter with reference to the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 of the drawings diagrammatically shows an information recording apparatus constructed in accordance with the teachings of the present invention;
FIG. 2 is a graphical illustration showing the relationship between the reference density signal of the present invention and an external information signal;
FIGS. 3A and 3B semi-schematically illustrate embodiments of the reference density or concentration signal generating circuits;
FIG. 4 semi-schematically illustrates an embodiment of the control means;
FIGS. 5A and 5B show detailed examples of the reference density signal and the corresponding patterns thereof;
FIG. 6 semi-schematically illustrates an embodiment of the reference density signal generating circuit;
FIG. 7 semi-schematically illustrates the internal structure of the reference density signal generating circuit shown in FIG. 6; and
FIG. 8 graphically depicts the formation of the reference density signal.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Around a photosensitive drum 1 (which carries on its surface a photosensitive member 1a the combinations hereinafter being conveniently designated, at times photosensitive drum 1. There are successively disposed a charging electrode 2 for uniformly charging drum 1, a scanning reproducing device 3 (such as a cathode ray tube (CRT), an optical fiber tube (OFT), or the like) for forming on member 1a an image corresponding to an external information signal developing means 4 for developing the electrostatic latent image formed by scanning reproducing device 3 on photosensitive member 1a, a transfer electrode 6 for transferring the developed external information signal image onto a recording paper P supplied from recording paper feeding tray 5, a separation electrode 7 for separating the recording paper bearing the transferred image from photosensitive drum 1, an electrode 8 for neutralizing or reducing residual charge remaining on the surface of photosenstive member 1a from which the recording paper P has been separated, and cleaning means 9 for removing the residual toner from photosensitive member 1a. On the developing means 4, toner replenishing means 41 for replenishing toner is disposed. The recording paper P that has been separated from photosensitive member 1a is transported by transport means 10 to fixing means 11, by the action of which the toner image is fixed on the recording paper, and finally the paper is ejected to a receiving tray 12.
A photoelectric detector 13 is disposed close to the surface of photosensitive member 1a between developing means 4 and transfer electrode 6. Photoelectric detector 13 may be of a conventional type composed of a light emitting element and a light receiving element the output of which is supplied to a control means 14. Toner replenishing means 41 is provided with driving means 15 which operates, in accordance with a control signal from control means 14, a valve 41a so as to open the valve means when necessary to supply toner to developing means 4.
The toner concentration control method of the present invention is such that, as shown in FIG. 2, a reference density signal is inserted prior or subsequent the external information signal to be supplied to scanning reproducing device 3, and an optical image corresponding to the reference information signal is projected onto photosensitive member 1a prior or subsequent to the signal image corresponding to the external information. The latent image formed on member 1a from the reference signal is thereafter developed by developing means 4 to form a visible reference density region on the surface of photosensitive member 1a. The reference density signal, in this embodiment of the invention, is a luminance signal having a definite amplitude 3A shows a circuit for inserting the reference density signal prior to the external information signal, and FIG. 3B shows a circuit for inserting the reference density signal after the external information signal. In these circuits, reference numeral 20 denotes a cathode ray tube which is an integral part of scanning reproducing device 3, 21 is a monostable multivibrator or one-shot connected to a source generating the external information signals, 22 is a delay circuit the input of which is connected to a line extending from the source and the output of which is grounded through a resistor (no reference symbol), 23 is a variable resistor adjustable for setting the desired toner concentration. The wiper of variable resistor 23 is connected to the cathode of CRT 20 so as to vary the potential thereof in conjunction with the output of delay circuit 22. The reference density region reflects the toner concentration of the developer then in use because the region is developed with the very developer that develops the external information image. The density of this reference density region is converted by photoelectric detector 13 into an electric signal to be supplied to control means 14 which may be implemented by such a circuit as is shown in FIG. 4, comprising a sensitivity setter 14a, comparator 14b, and a microcomputer controller 14c. The output of photoelectric detector 13 is compared at comparator 14b to the reference value determined by sensitivity setter 14a, and the output of comparator 14b is fed to microcomputer controller 14c. The output of controller 14c is supplied to driving means 15 (which includes a solenoid) to open and shut toner replenisher valve 41a. Sensitivity setter 14a for setting the desired toner concentration when replenished is composed of a variable resistor.
Although the reference density signal for the reference image may be a luminance signal having a definite amplitude lasting a certain period of time as shown in FIG. 2, if the reference signal has a plurality atternatively of definite amplitude pulses as shown in FIGS. 5A and 5B, it provides the advantageous ability to prevent the so called "edge effect" phenomenon. To the reference density signals of FIGS. 5A and 5B, the corresponding reference density regions are formed as shown at the lower portions of the same figures. In addition, to those shown in the drawings, the reference density region may be formed as on arbitrary pattern by properly changing and combining the number of pulses, their amplitude, their time and periods, and the variation and selection of such patterns are readily achievable.
An example of a circuit for generating the reference density signals shown in FIGS. 5A and 5B is described hereinafter.
In FIG. 6, a reference density region pattern generator 24 is connected to microcomputer controller 14c to generate a pattern signal in accordance with the control signal from the controller 14c. In this case, the reference density signal may be inserted at an arbitrary position either before or after the external information signal by changing the timing of the reference density beginning or initiating signal. Reference numeral 25 denotes a variable resistor for setting the desired toner concentration.
FIG. 7 is a block diagram showing the internal structure of reference density region pattern generator 24, wherein counter CL is a circit for determining the formation of the reference density region by the number of scanning couts from the insertion of the reference density region; i.e., the length of the reference density region. TC is a counter for determining the position at which the reference density region should be formed, TP is a counter for determining the width of the reference density region, and G1, G2, G3, and G4 are gates.
The operation is described below, in reference to FIGS. 7 and 8, wherein fL is a synchronizing signal of one scanning corresponding to the deflection signal of scanning reproducing device 3 in the drawing, and wherein fH is a high speed pulse signal, generated synchronously with fL, the former being gated together with the latter in gate G2 to yield waveform S1. Counter TC counts waveform signal S1 to open gate G3 when reaching the given count number (postion setting) to feed signal S1 to counter TP, which outputs the number of pulses of signal S1 corresponding to the designated width of the reference density region, which output is then gated together with the signal of counter CL in gate G4 to output the desired reference density signal.
The above described embodiments includes an optical scanning reproducing device------such as an optical fiber tube (OFT), thin wall tube (TWT), laser beam scanning device, etc.,------used as the scanning reproducing means for converting the electric signal of external information into an optical image. It should, however, be understood that the present invention is also applicable to such recording means as the electrostatic recording facsimile type which directly electrostatically records external information. In addition, in this invention, the reference density signal should be inserted either before or after the external information signal in order to avoid the placement of unnecessary information on the recording paper.
According to the present invention, by merely inserting the reference density signal either before or after the external information provided in the form of an electric signal, the reference density region may be formed through an ordinary electrophotographic process. Thus, merely by providing a photoelectric means or circuit for detecting the density of the reference density region the toner concentration of developer can be detected, and the method of this invention is accordingly simple and economical as compared to conventional methods for the detection of toner concentration. Further, being in the form of an electric signal, the reference density signal enables ready modification of the pattern of the reference density region by varying and combining its electrical characteristics (such as amplitude, period, etc.) and also enables prevention of the edge effect in the reference density region and an increase in the accuracy of the detection and control of toner concentration. In addition, those skilled in the art will recognize that a fixed resistor may be used in place of each disclosed variable resistor. | A method of controlling toner concentration in an electrophotographic recording apparatus includes placement of a reference image in the form of a density pattern on the electrostatic member preceding or following an information image thereon. Photoelectric sensing of this pattern controls selective addition of toner to the developer and variation in the pattern to maintain a predetermined concentration of toner therein in accordance with the sensed density of the developed reference image. The pattern is preferably in the form of pulses to avoid edge effects. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[0002] Not Applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX
[0003] Not Applicable.
BACKGROUND OF THE INVENTION
[0004] The present invention relates generally to packaging and storage containers, and more specifically to packaging having a first surface containing shipping, mailing, content or other indicia, said packaging possessing additional exterior panels which are reversible for conversion into packaging displaying a second surface containing gift wrapping, decorative markings, advertising, and/or other indicia, said conversion possible without revealing the contents of the package.
[0005] The internet, though e-mail, voice over internet protocol, and transmission of visual images, has diminished the perception of geographical distances, allowing for the formation and maintenance of relationships over great distances in a way that was not possible or economical previously. With this has come the need to transmit gifts over these large distances to an extent that did not exist previously.
[0006] The internet has had a similarly profound effect on commerce, diversifying the nature and quality of goods available for purchase by the modern consumer. The internet has also enabled formerly regional sellers to reach markets over great distances. As such, this development in commerce has resulted in the transfer of merchandise not through personal pickup, but through mail or courier delivery.
[0007] Internet commerce has not changed the peak season for shopping, in November and December, but it has changed the way people shop, and how those orders are fulfilled even enabling transactions where the buyer, seller and recipient are great distances apart.
[0008] Because gifts are transported to recipients across distances, and because mail services and couriers require that shipped packages display only functional markings so as not to obscure recipient and postage information, gifts are not easily sent in decorative wrapping as is the custom for holidays, birthdays and other special occasions.
[0009] There are methods for the recipient to receive a decoratively wrapped gift purchased over the internet, but none are easy or economical. One option is for the gift to be wrapped prior to insertion into a second delivery box, but many merchants do not offer this service. If they do, it often involves extra resources, materials and expense. A second option is for the gift-giver to have the gift sent to them for wrapping, and thereafter re-sent to the recipient, which again involves packaging within packaging, and diminishes one advantage of internet shopping: the economies of direct shipping.
[0010] The problems outlined in the previous paragraph are not limited to internet commerce. Any gift sent by mail must be wrapped, and then inserted into additional packaging suitable for transport by mail or courier. This results in several burdensome demands on the gift-giver, who must (i) wrap the gift itself; (ii) find or purchase a box large enough to accommodate the gift; and (iii) pay any additional costs for shipment resulting from the increased mass of the packaging, and/or the increased dimensions of the outer box.
[0011] Despite these additional efforts, a gift sent in such duplicative packaging may still be subjected to increased risk of damage in transport as a result of any mismatch between the gift packaging and the shipping packaging. Where the size discrepancy is large, the inner box is permitted rattle in transit, potentially causing damage to the shipped good. Where the size discrepancy is very small, the outer box may rupture in transit, again causing damage to the shipped good.
[0012] As a result, there is a need for packaging that is both versatile and durable. It should be cost effective and capable of rapid assembly using a single sheet manufactured from available materials. It should support environmentalism and recycling efforts by avoiding waste, being constructed of post-consumer recycled materials, and ideally by being capable of re-use.
[0013] The concept of a foldable containers is well established in the prior art. Foldable containers are disclosed in U.S. Pat. No. 1,148,219 of Cornell for a folding box, U.S. Pat. No. 1,509,383 of Walter for a box, U.S. Pat. No. 5,007,580 of Morrison for a foldable container, and U.S. Pat. No. 5,588,585 of McClure for a corner-reinforced carton.
[0014] The concept of a convertible container has similarly been disclosed in the prior art. U.S. Pat. No. 3,357,543 issued to Taggart, discloses the use of two display boxes hinged together in book fashion, which convert to gift boxes by closing the “book” so that the window of each display box is covered by the opposing display box. U.S. Pat. No. 5,673,796 issued to Tulloch discloses packaging convertible from a box suitable for retail display of its contents to a box suitable for a gift box. Neither of these patents contemplates shipping, and neither allows for the contents of the packaging to be concealed for gift-giving purposes. Furthermore, neither is capable of manufacture from a single sheet of material, making these designs uneconomical.
[0015] U.S. Pat. No. 5,344,065 issued to Moran discloses a reversible container having opposite surfaces for shipping, disassembly at its destination and reassembly for display of the everted second surface. U.S. Pat. No. 6,948,616 issued to Gillani discloses a reversible shipping container alternately folded to reveal or conceal a commercial logo or other visible marking. While both of these inventions expressly contemplate shipping, both require the contents of the packaging be exposed and expelled in order to accomplish the conversion. For gift-giving purposes, this is an undesirable requirement.
[0016] The prior art fails to disclose a reversible foldable container which can be converted from a package displaying a first surface to a package displaying a second surface, without revealing the contents of the packaging to the recipient. None of the above-noted patents, taken either singly or combination, are seen to disclose the specific arrangement concepts disclosed by the present invention.
BRIEF SUMMARY OF THE INVENTION
[0017] It is therefore an object of the present invention to provide an improved container capable of conversion from a container having a first surface to a container having a second surface, which conversion is possible while preserving the contents from inspection by the recipient until a time of the recipient's own choosing.
[0018] Another object of the present invention is to provide an improved container which said first surface provides means for shipping, mailing and/or content information thereon, and which said second surface provides means for the placement of decorative markings, advertising, and/or other indicia thereon.
[0019] Still another of the objects of the present invention is to provide an improved container which includes reversible sealing means, which sealing means may be separated to open the outer container without disturbing the contents of the inner container, and which sealing means may then be reversed to close the everted container to present a decoratively wrapped gift to the recipient.
[0020] Yet another of the objects of the present invention is to provide an improved container which may be formed from a single sheet of material such as corrugated or non-corrugated fiberboard material, cardboard, synthetic materials, plastics, etc.
[0021] A final object of the present invention to improve over the disadvantages of the prior art.
[0022] With these and other objects in view which may more readily appear as the nature of the invention is better understood, the present invention consists in the novel combination and arrangement of parts hereinafter more fully described, illustrated and claimed with reference being made to the attached drawings.
[0023] By the present invention, an improved container providing for the reversibility of said container's outer surface is disclosed.
[0024] The present invention in its preferred format discloses a foldable carton container which is reversible, displaying alternatively a surface suitable for post, courier or other shipment which contains markings necessary or desirable to facilitate such delivery, and on the reverse side contains decorative markings, advertising, and/or other indicia
[0025] The present invention is made of any substantially flat resilient material which can cut into a pattern for creating a reversible container, including but not limited to corrugated or non-corrugated cardboard and plastic, flexible metals, alloys, synthetic and natural treated fabrics, paper or paper board stock.
[0026] The present invention is made of connected panels which are either permanently affixed with adhesive, or with reversible tabs used to seal the outer surface of the container when inserted into adjacent slots in either manifestation of the packaging.
[0027] Creasing is used along fold score lines so that the panels can be easily folded along the crease lines, and in either direction where reversible lines are contemplated, with ease. Decorative markings are printed only on one side, as are the shipping markings, allowing the packaging to be assembled with either set of markings visible from the exterior.
[0028] To assemble the packaging, the first set of four panels are folded up to form a conventional carton. If desired, an adhesive can be used to secure the tab on the first panel to the inside of the fourth panel, to secure the inner box. Side panels are also folded in to secure the sides of the inner container, and may also be secured with adhesive means if desired.
[0029] The second set of four panels, which are creased to bend in either direction, form the outer surface of the container. To assemble the packaging displaying the first surface (for example, a surface suitable for shipping), the remaining four panels are folded up in the same direction as the four panels comprising the inner container, and are secured either with adhesion or through use of tabs as illustrated. The larger side panels are then folded inward to cover the entirety of the inner container, now displaying only the first surface, and can be secured either with adhesion or by insertion of tabs as illustrated.
[0030] To convert the packaging such that the second surface (for example, a surface suitable for gifting) is displayed, the outer four panels discussed in the last sentence of the preceding paragraph are detached and folded in the opposite direction so that said four panels again cover the four panels of the inner container, where they may again be secured either with adhesion or tabs, but this time in the opposite direction. Similarly, the side panels are reversed in direction in order to cover the sides, providing complete coverage of the entire inner container, this time with the second surface displayed.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0031] The present invention can best be understood in conjunction with the accompanying drawings, in which:
[0032] FIG. 1 is a top plan view of the flat die cut container of the present invention, prior to assembly;
[0033] FIG. 2 is an isometric view of the container at the commencement of closure;
[0034] FIG. 3 is an isometric view of the package at the point where the contents of the inner container become sealed, and prior to commencement of enclosing said inner container with the outer panels that will form the outer first surface;
[0035] FIG. 4 is an isometric view of the container where the outer surface of the container in its first manifestation (displaying the first surface) is near completion;
[0036] FIG. 5 is an isometric view of the container where at the onset of conversion into a container having the second surface; and
[0037] FIG. 6 is an isometric view of the container after completion of conversion, displaying the second surface.
DETAILED DESCRIPTION OF THE INVENTION
[0038] FIG. 1 illustrates the present invention prior to assembly. The outer contour is die cut usually with a steel rule die. Internal features are also cut in the same pass, such as the tab holes 60 , 62 , and 64 . The creasing is also performed by non-cutting die members in the same pass.
[0039] FIG. 2 shows the container where the panels 10 , 12 , 14 and 16 have initiated closure, and the adhesive strip film 61 has been removed, revealing adhesive surface 60 which, when affixed to panel 16 , will seal the inner container. Side panel pairs 26 and 30 , and 34 and 38 are at this point closed, while side panel pairs 28 and 32 , and 36 and 40 remain open to reveal construction features.
[0040] FIG. 3 shows the container where the inner container is now sealed, with side panels 28 and 32 (visible) and panels 36 and 40 (not visible) now closed over side panels 26 and 30 , and panels 34 and 38 , respectively. At this point, panel 8 (and optional adhesive surface 60 ) are in contact with panel 16 , sealing the inner container. Folding continues in the same direction of the folding of the inner container (panels 10 , 12 , 14 and 16 ). It is to be noted that the side panels 26 , 28 , 30 , 32 , 34 , 36 , 38 and 40 may be folded in different combinations and with different panels in said series comprising the exterior surface of the inner container, as desired. Furthermore, these same exterior side panels, when closed, may be further secured with packing tape, staples or other adhesive means at this point in the process, if desired (similarly to panel 8 ).
[0041] The crease lines of the inner container, namely lines 9 , 11 , 13 , 15 25 , 27 , 29 , 31 , 33 , 35 , 37 and 39 , employ unidirectional creasing on only the top (visible) surface. To make the outer surface of the container (panels 18 , 20 , 22 and 24 , and corresponding side panels 44 and 46 ) reversible, the crease lines corresponding to said outer surface panels (crease lines 17 , 19 , 21 , 23 , 41 , 43 , 45 , 47 , 49 , 51 and 53 ) denote creasing on both top and bottom surfaces such that the panel members 18 , 20 , 22 , 24 , 44 , 46 , and tab panel members 42 , 48 , 50 , 51 and 52 can be easily folded 90 degrees in either direction along their respective crease fold lines with equivalent ease.
[0042] FIG. 4 shows the container where the outer surface of the container in its first manifestation (displaying the first surface) is near completion. At this stage, panel 10 is in contact with panel 18 , panel 12 is in contact with panel 20 , panel 14 is in contact with panel 22 . Panel 16 is positioned to make contact with panel 24 , and side panels 44 and 46 are being folded in a 90 degree angle to make contact with panels 28 and 32 (in the case of panel 44 ) and panels 36 and 40 (in the case of panel 46 ). Tabs 50 , 51 and 52 are positioned for insertion into slots 60 , 62 and 64 , respectively. Tabs 42 and 48 will then be capable of being folded 90 degrees and inserted in the space between panels 12 and 20 , forming a triple-layer of coverage of the sides of the closed container, a double-layer of coverage on the remaining surfaces, and completing coverage of the inner container with the first surface.
[0043] FIG. 5 shows the commencement of conversion into a container having the second surface displayed. Tabs 42 and 48 have been removed, and tabs 50 , 51 and 52 have been removed from slots 60 , 62 and 64 , respectively. The panels constituting the remainder of the outer surface, namely panels 24 , 22 , 20 and 18 , are being wrapped around the inner container in the opposite direction as in the first manifestation of the container (displaying the first surface).
[0044] FIG. 6 shows the container after completion of conversion, displaying the second surface. At this stage, panel 16 is in contact with panel 18 , panel 14 is in contact with panel 20 , panel 12 is in contact with panel 22 , and panel 10 is in contact with panel 24 . Side panels 44 and 46 are again in contact with panels 28 and 32 (in the case of panel 44 ) and panels 36 and 40 (in the case of panel 46 ), this time accomplishing the coverage from the reverse direction. Tabs 50 , 51 and 52 are again folded in a 90 degree angle and inserted into slots 60 , 62 and 64 , respectively, also from the reverse direction as in the first manifestation illustrated in FIG. 4 . Finally, Tabs 42 and 48 have been inserted in the space formed between panels 14 and 20 (as contrasted with panels 12 and 20 in the first manifestation), once again forming a triple-layer of coverage of the sides of the closed container, a double-layer of coverage on the remaining surfaces, and completing coverage of the inner container with the second surface.
[0045] It is noted that in order to accomplish complete coverage of the inner container composed of panels 10 , 12 , 14 and 16 , it is necessary for the covering reversible panels 18 , 20 , 22 and 24 to be of a length equal to the length of the corresponding inner container panel, plus two times the thickness of said corresponding panel. To give an example, if each of panels 10 , 12 , 14 , 16 were to have a width of X, a length of Y and a thickness of Z, the resultant effect would be for panels 18 , 20 , 22 and 24 to have a width of X+2Z, a length of Y+2Z, and a thickness of Z. The uniform thickness permits the construction of the entire container from a single sheet of material.
[0046] It is further noted that other modifications may be made to the present invention, such as different configurations for the foldable panels, so long as the modifications are made within the scope of the present invention, as noted in the appended claims.
[0047] Although various embodiments of the present invention have been disclosed here for purposes of illustration, it should be understood that a variety of changes, modifications and substitutions may be incorporated without departing from either the spirit or scope of the present invention. Examples include different dimensions and configurations for the foldable panels and closures, alternative forms of adhesion, and an infinite number of functional, descriptive, decorative or whimsical markings on each of the two surfaces. Thus the scope of the present invention should be determined by the appended claims and their legal equivalents, rather than by the examples given. | The present invention relates to packaging formed of a single sheet of material and incorporating reversible panels, alternatively displaying a first surface (which could display address and postage markings to facilitate shipping), and after conversion, a second surface (which could display decorative markings for holiday or special occasion gift giving). Conversion from the first manifestation to the second is accomplished through manipulation of the reversible panels, allowing conversion without exposing the contents of the package. Construction may be of standard shipping materials such as corrugated cardboard, but due to the additional thickness and stability offered by the design, non-corrugated cardboard or fiberboard are expressly contemplated, as are synthetic sheet material and plastics where the packaging is to be reused. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a hard film, which is formed on a surface of a cutting tool such as a tip, a drill, and an end mill, and a surface of a plastic working tool such as a forging die and a punch for improving wear resistance of the tools, and relates to a method useful for manufacturing such a hard film.
[0003] 2. Description of Related Art
[0004] Usually, coating of a hard film of TiN, TiCN, TiAlN or the like has been performed for the purpose of improving wear resistance of a cutting tool using sintered hard alloy, cermet, or high speed tool steel as a base material. In particular, since a composite nitride of Ti and Al (hereinafter, abbreviated as “TiAlN”) exhibits excellent wear resistance as disclosed in Japanese Patent No. 2644710, a film of the composite nitride is increasingly used for a cutting tool for cutting a very hard material (work material) such as a high speed cutting material or hardened steel in place of a film including nitride (TiN) or carbonitride (TICN) of Ti.
[0005] However, a film further improved in wear resistance is now required with recent increase in hardness of work material or increase in cutting speed.
[0006] The hard film is further required to have oxidation resistance under high temperature. In the TiAlN film as above, oxidation resistance is comparatively high, and oxidation starts near 800 to 900° C., however, there is a difficulty that deterioration of the film tends to progress under a more severe environment. Therefore, a hard film is proposed, in which the TiAlN film is added with Cr, thereby the concentration of Al is increased while keeping a cubic crystal structure with high hardness, and consequently oxidation resistance is further improved (e.g., JP-A-2003-71610). Moreover, a hard film is proposed, in which oxidation resistance is further improved by adding Si or B into a TiCrAlN film (e.g., JP-A-2003-71611), or a hard film is proposed, in which oxidation resistance is further improved by adding Nb, Si or B into a CrAlN film (e.g., WO2006-005217) is proposed.
[0007] However, the hard films proposed so far cannot be regarded to be excellent in wear resistance and oxidation resistance, and actually, further improvement in properties is desired.
SUMMARY OF THE INVENTION
[0008] In view of foregoing, it is desirable to provide a hard film that is obviously excellent in wear resistance, and exhibits excellent oxidation resistance even under a condition that hot heat generation easily occurs due to friction heating, consequently exhibits excellent properties compared with a usual hard-film including TiAlN, TiCrAlN, TiCrAlSiBN, CrAlSiBN, or NbCrAlSiBN, and provide a method useful for manufacturing such a hard film.
[0009] A hard film of an embodiment of the invention is summarized in that it includes (M) a Cr b Al c Si d B e Y f Z (however, M is at least one element selected from a group 4A element, a group 5A element, and a group 6A element (except for Cr) in the periodic table, and Z shows one of N, CN, NO and CNO), wherein
[0010] a+b+c+d+e+f=1,
[0011] 0≦a≦0.3, 0.05≦b≦0.4, 0.4≦c≦0.8, 0≦d≦0.2, 0≦e≦0.2, and 0.01≦f≦0.1, (a, b, c, d, e and f show atomic ratios of M, Cr, Al, Si, B and Y respectively).
[0012] Moreover, such a subject can be achieved by a hard film including Cr b Al c Si d B e Y f Z (however, Z shows one of N, CN, NO and CNO), wherein
[0013] b+c+d+e+f=1,
[0014] 0.2≦b≦0.5, 0.4≦c≦0.7, 0≦d≦0.2, 0≦e≦0.2, and 0.01≦f≦0.1 (however, d+e>0),
[0000] (b, c, d, e and f show atomic ratios of Cr, Al, Si, B and Y respectively)
[0015] As a preferable mode of the hard film of an embodiment of the invention, a hard film is given, in which hard films as above (within a composition range shown as above) are alternately stacked with compositions being different from each other, and thickness of each layer is between 5 nm and 200 nm.
[0016] When the hard film as above is manufactured, the hard film is preferably formed by a cathode discharge arc ion plating method.
Advantage of the Invention
[0017] The hard film of an embodiment of the invention is in a hard film structure as expressed by a certain expression, thereby a hard film can be achieved, in which wear resistance is obviously excellent, and deterioration in property due to oxidation is not caused even under a condition that hot heat generation easily occurs due to friction heating. Such a hard film is extremely useful as a hard film formed on surfaces of base materials of various cutting tools, or plastic working tools such as a forging die and a punch.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a schematic illustrative diagram showing a configuration example of an arc ion plating apparatus (AIP apparatus) for manufacturing the hard film of an embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] The inventors made investigation from various points of view to further improve high-temperature resistance (oxidation resistance) of a hard film. As a result, they found that Cr was contained as an indispensable component, and Y was contained in place of Si or B being regarded to be effective for improving oxidation resistance, or contained in addition to Si or B, leading to extreme improvement in oxidation resistance of a hard film, consequently completed an embodiment of the invention. Hereinafter, a reason for selecting each element in the hard film of an embodiment of the invention, and a reason for limiting a composition range of each element are described.
[0020] The hard film of an embodiment of the invention is expressed by the following general expression (1). A reason for selecting each element in the hard film of an embodiment of the invention, and a reason for limiting a composition range of each element are described.
[0000] (M) a Cr b Al c Si d B e Y f Z (1),
[0000] (a, b, c, d, e and f show atomic ratios of M, Cr, Al, Si, B and Y respectively, and Z shows one of N, CN, NO and CNO).
[0021] A metal element M is at least one element except for Cr selected from a group 4A element, a group 5A element, and a group 6A element (Ti, Zr, Hf, V, Nb, Ta, Mo and W) in the periodic table. The metal element exhibits an operation of forming a nitride (MN) having high hardness in a film, and thus increasing film hardness. However, since nitrides of the elements are bad in oxidation resistance compared with CrN, large content of the metal element M reduces oxidation resistance of a film. Therefore, an upper limit of an atomic ratio of M in the film needs to be 0.3 (that is, when a+b+c+d+e+f=1 is given, a needs to be 0.3 or less).
[0022] Moreover, when the metal element M is not contained at all, hardness tends to be slightly decreased, therefore a lower limit of the metal element is more than 0 (that is, a>0). A preferable range of the metal element M is 0.02 to 0.2 in the light of oxidation resistance and hardness. As the metal element M, Ti or Hf is preferably selected in the light of hardness, and Nb is preferably selected in the light of oxidation resistance and hardness.
[0023] The hard film of an embodiment of the invention contains Cr as an indispensable component. Cr is a necessary element for configuring the film to improve oxidation resistance of the film, and dissolve AlN in a CrN nitride of a cubic rocksalt type to form metastable cubic AlN. A lower limit of an atomic ratio of Cr needs to be 0.05 (that is, a subscript b is not less than 0.05) in the hard film so that Cr exhibits such effects. However, CrN is low in hardness compared with the nitrides of M, and excessive content of Cr may cause reduction in hardness of a film. Therefore, an upper limit of Cr is 0.4 (that is, b≦0.4). A preferable range of the Cr content is in a range of 0.1 to 0.25 in an atomic ratio (0.1≦b≦0.25).
[0024] Al is an element necessary for improving oxidation resistance of a hard film, and needs to be contained in an atomic ration of 0.4 or more (that is, c≧0.4) to exhibit such an effect. However, since a stable phase of AlN primarily includes a hexagonal structure, when Al is excessively contained and significantly exceeds the total sum of added amount of metal elements M and Cr, transfer into a hexagonal structure occurs, resulting in softening of a film. Therefore, an upper limit of an atomic ratio of the content of Al needs to be 0.8 (that is, c≦0.8). A preferable range of the Al content is 0.5 to 0.6 in an atomic ratio (0.5≦c≦0.6).
[0025] Si, B and Y are added in a film with an upper limit of 0.2 (0.1 in the case of Y) in an atomic ratio to improve oxidation resistance respectively. Since Y has the largest effect of improving oxidation resistance among them, Y needs to be added in an atomic ratio of 0.01 or more (that is, f≧0.01).
[0026] Addition of Si and B provides an operation of fining crystal grains of a film and thus increasing hardness, in addition, when Si and B are contained together with Y, an effect of further improving oxidation resistance is provided. Si and B are preferably added in an atomic ratio of 0.03 or more (that is, d≧0.03, e≧0.03) to exhibit such effects respectively. However, since addition of the elements tends to cause a film to be transferred into an amorphous or hexagonal structure, upper limits of them are specified to be 0.2 in Si, 0.02 in B, and 0.1 in Y (that is, d≦0.2, e≦0.2, and f≦0.1) respectively. As a more preferable range, Si of 0.03 to 0.07, B of 0.05 to 0.1, and Y of 0.02 to 0.05 are given.
[0027] The hard film of an embodiment of the invention may include any form of a nitride, carbonitride, nitrogen oxide, and carbon-nitrogen oxide (Z is N, CN, NO or CNO in the general expression (1)). However, preferably, the form is essentially anitride, and a ratio (atomic ratio) of N in Z is 0.5 or more. More preferably, the ratio is 0.8 or more. As an element other than N, C or O is contained as the remainder.
[0028] In an application requiring more improved oxidation resistance, a composition of the hard film contains Cr and Y as indispensable components as expressed in the following general expression (2), thereby stability can be added at further high temperature.
[0000] Cr b Al c Si d B e Y f Z (2),
[0000] (b, c, d, e and f show atomic ratios of Cr, Al, Si, B and Y respectively, and Z shows one of N, CN, NO and CNO).
[0029] In such a hard film, since the metal element M being a stabilizing element of the cubic rocksalt structure is not present, a crystal structure is easily transferred into a hexagonal structure in a case of some Al content. Therefore, the content of Cr needs to be 0.2 or more (that is, b≧0.2) to stabilize a cubic AlN compound. However, when Cr is excessively contained, hardness is decreased even if a crystal structure is cubic. Therefore, an upper limit of the content of Cr needs to be 0.5 (that is, b≦0.5). A preferable range of the Cr content is about 0.3 to 0.4 in an atomic ratio (that is, 0.3≦b≦0.4).
[0030] Regarding the Al content in the hard film, since the hexagonal structure is easily formed in the hard film, an upper limit of the Al content is specified to be 0.7. More preferably, it is 0.5 to 0.6 (that is, 0.5≦c≦0.6). Regarding Si, B and Y, a specified range and a preferable range are the same as in the hard film expressed in the general expression (1). However, at least one of Si and B needs to be contained (that is, d+e>0) in the light of fining of film crystal grains and increase in hardness by adding Si or B.
[0031] The hard film of an embodiment of the invention needs not be wholly configured by a film having a single composition, but may be a hard film of a stacked type in which at least one or two layers are stacked, the layers having different compositions from one another in the composition range of the general expression (1) or (2). As an example (combination) of such a stacked-type hard film, TiCrAlSiYN/NbCrAlYN, TiCrAlBYN/HfCrAlYN and the like are given. In these examples, compositions of the films are made different from each other by changing kinds of elements configuring the respective films. However, even in a combination of the same element, compositions can be made different from each other by differing composition ranges from each other.
[0032] When the films different in composition or element are stacked as above, since lattice constants of the films are different from each other, lattice distortion is induced between layers, leading to further increase in hardness of the films. In the case that the films are stacked, thickness of each layer is preferably 5 nm or more, and when the thickness is less than 5 nm, the films exhibits the same performance as that of a film having a single structure. When thickness of each layer exceeds 200 nm, since the number of stacking is decreased because thickness of about several micrometers is required for a cutting tool or other tools, the number of interfaces in which distortion is stored is decreased, consequently the effect of increase in hardness is hardly obtained. More preferably, thickness of each layer is about 10 to 100 nm.
[0033] While a method of manufacturing the hard film of an embodiment of the invention is not particularly limited, a PVD method using a solid target is recommended for the method. In particular, the cathode discharge arc ion plating method (AIP method) is preferably used. In formation of the hard film of a multi-component system as above, if a sputtering method is used, difference in target composition is increased between a target composition and a film composition. However, such a difficulty of difference in composition is substantially eliminated in the AIP method. Moreover, there is an advantage that since an ionization ratio of a target element is high in the AIP method, a formed film is tight and high in hardness.
[0034] In the hard film of an embodiment of the invention, the hard film is provided as a stacked film in which films are stacked, the films having compositions as shown in the general expression (1) or (2) respectively, thereby film performance can be improved. However, the stacked film can be configured by combining a film having the relevant composition and a hard film having a composition other than the film composition as shown in the general expression (1) or (2). For example, the film can be configured by stacking a film including a nitride, carbide, or carbonitride of at least one element selected from a group including a group 4A element, a group 5A element, and a group 6A element in the periodic table, and Al, Si, and B, and a film having a composition as shown in the general expression (1) or (2). As such a film, a film of TiAl(CN), TiCrAl(CN), CrAl(CN), TiSi(CN), TiVAl(CN), TiNbAl(CN), NbCrAl(CN) or the like is exemplified.
[0035] FIG. 1 is a schematic illustrative diagram showing a configuration example of an arc ion plating apparatus (AIP apparatus) for manufacturing the hard film of an embodiment of the invention. In the apparatus shown in FIG. 1 , a turntable 2 is disposed within a vacuum chamber 1 , and four rotation tables 3 are symmetrically attached to the turntable 2 . Each rotation table 3 is mounted with a body to be treated (base material) 5 . Around the turntable 2 , a plurality of (two in FIG. 1 ) arc evaporation sources 6 a , 6 b (cathode side), and heaters 7 a , 7 b , 7 c and 7 d are disposed. Arc voltage sources 8 a , 8 b are disposed at respective sides of the evaporation sources 6 a , 6 b to evaporate the sources respectively.
[0036] In the figure, 11 is a filament-type ion source, 12 is an AC power supply for filament heating, and 13 is a DC power supply for discharge, wherein a filament (made of W) is heated by current from the AC power supply for filament heating 12 , then emitted thermoelectrons are introduced into the vacuum chamber by the DC power supply for discharge 13 , so that plasma (Ar) is generated between the filament and the chamber to generate Ar ions. Cleaning of the body to be treated (base material) is performed using the Ar ions. The inside of the vacuum chamber is configured in such a way that the inside is evacuated to a vacuum by a vacuum pump P, and various kinds of deposition gas is introduced through a mass flow controller 9 a , 9 b , 9 c or 9 d.
[0037] Targets having various compositions are used for the respective evaporation sources 6 a , 6 b . The turntable 2 and the rotation tables 3 are rotated while the targets are evaporated in a deposition gas (C-source-contained gas, O 2 gas, and N-source-contained gas, or diluted gas of them with inert gas) using the filament-type ion source 11 , thereby hard films can be formed on a surface of the body to be treated 5 . In the figure, 10 is a bias voltage source provided for applying a negative voltage (bias voltage) to the base materials 5 .
[0038] The hard film of the stacked type can be achieved (1) by using a plurality of different arc evaporation sources 6 a , 6 b , in addition, it can be achieved (2) by periodically changing a negative voltage (bias voltage) applied to the body to be treated 5 , or (3) by changing an atmospheric gas. In particular, a ratio of the C-source-contained gas in the atmospheric gas is periodically changed to stack at least two kinds of films having values of carbon in the expression (1) being different from each other.
[0039] Control of a period of the hard film of the stacked type (repetition period of stacking) and thickness of each layer can be achieved by controlling rotation frequencies of the turntable and rotation tables and input power for the respective evaporation sources (proportional to the amount of evaporation) in the (1), time for applying the bias voltage in the (2), and time for introducing the atmospheric gas in the (3).
[0040] As a base material for forming the hard film of an embodiment of the invention, sintered hard alloy, cermet, cBN or the like is given as an applicable tool material, the hard film can be applied to an iron-based alloy material such as cold-worked tool steel, hot-worked tool steel, or high speed tool steel.
[0041] While the invention is described more specifically with examples hereinafter, it will be appreciated that the invention is not restricted by the following examples, and the invention can be obviously carried out with being appropriately altered or modified within a scope suitable for the content described before and after, and all of such alterations or modifications are encompassed within a technical scope of the invention.
EXAMPLES
Example 1
[0042] A target containing M, Cr, Al, Si, B and Y in various ratios was disposed on the arc evaporation source 6 a of the apparatus (AIP apparatus) shown in FIG. 1 , and a super-alloy tip, a super-alloy boll end mill (10 mm in diameter, two flute) as the bodies to be treated 5 , and a platinum foil for an oxidation test (30 mm in length, 5 mm in width, and 0.1 mm in thickness) were mounted on the rotation tables 3 , then the inside of the vacuum chamber was evacuated into a vacuum. Then, the bodies to be treated 5 were heated to a temperature of 550° C. by the heaters 7 a , 7 b , 7 c and 7 d disposed within the vacuum chamber 1 , and subjected to cleaning using Ar ions (Ar, pressure of 0.6 Pa, voltage of 500 V, and time of 5 min), and then nitrogen gas (N 2 gas) was introduced to increase pressure in the chamber 1 to 4.0 Pa to start arc discharge, consequently hard films 3 μm in thickness were formed on surfaces of the bodies to be treated 5 . When C or O was contained in the film, methane gas (CH 4 gas) or oxygen gas (O 2 gas) was introduced into the deposition apparatus in a range of flow ratio to N 2 gas of 5 to 50 in volume percent. During deposition, a bias voltage of 20 to 100 V was applied to a substrate such that electric potential of the bodies to be treated 5 is negative with respect to ground potential.
[0043] For obtained hard films, metal compositions in the films were measured by EPMA, and Vickers hardness (load of 0.25 N, and holding time of 15 sec) was investigated. Moreover, crystal structures of the films, and characteristics (oxidation start temperature, and wear width) of the films were evaluated.
Analysis Condition of Crystal Structure
[0044] Evaluation of the crystal structures were performed by X-ray diffraction in θ-2θ using an X-ray diffraction apparatus manufactured by Rigaku Corporation. At that time, X-ray diffraction for a cubic structure was performed using a CuKα radiation source, and peak intensity for ( 111 ) face was measured near 2θ=37.780, peak intensity for ( 200 ) face near 2θ=43.90, and peak intensity for ( 220 ) face near 2θ=63.80. X-ray diffraction for a hexagonal structure was performed using the CuKα radiation source, and peak intensity for ( 100 ) face was measured near 2θ=32° to 33°, peak intensity for (102) face near 2θ=48° to 50°, and peak intensity for ( 110 ) face near 2θ=57° to 58°. A crystal structure index X was calculated using values of them according to the following expression (3), and crystal structures of the films were determined according to the following standard.
[0000] (IB(111)+IB(200)+IB(220))/(IB(111)+IB(200)+IB(220)+IH(100)+IH (102)+IH(110)) (3),
[0045] wherein IB( 111 ), IB( 200 ) and IB( 220 ) show peak intensity of respective faces of the cubic structure. IH( 100 ), IH( 102 ) and IH( 110 ) show peak intensity of respective faces of the hexagonal structure.
[0046] A case of the index X of 0.9 or more: cubic crystal structure (in the following tables, described as B 1 )
[0047] A case of the index X of not less than 0.1 and less than 0.9: mixed type (in the following tables, described as B 1 +B 4 )
[0048] A case of the index X of less than 0.1: hexagonal crystal structure (in the following tables, described as B 4 )
Oxidation Start Temperature
[0049] A platinum sample obtained in the example (platinum foil having a hard film formed thereon) was heated from room temperature at a heating rate of 5° C./min in artificial dry air, and change in mass of the sample was investigated by a thermobalance. Oxidation start temperature was determined from an obtained mass increase curve.
[0050] Using a test end mill obtained in the example (ball end mill made of sintered hard alloy having a hard film formed on a surface thereof), cutting was performed at the following cutting conditions with SKD 11 (HRC60) as a work material, then an edge was observed by a light microscope to measure wear width of a boundary portion between a cutting face and a flank.
[0051] Cutting speed: 150 m/min
[0052] Cutter feed: 0.04 mm/cutter
[0053] Axial cutting depth: 4.5 mm
[0054] Radial cutting depth: 0.1 m/s
[0055] Cutting length: 50 m
[0056] down cut, dry cut, and air blow only
[0057] Results of them are shown in the following Tables 1 and 2 together with the compositions of the hard films.
[0000]
TABLE 1
Amout
Sample
Hard film (atomic ratio)
Crystal
Hardness
Oxidation start
of wear
No.
M
Cr
Al
Si
B
Y
Sum
C
N
O
structure
(HV)
temperature (° C.)
(μm)
Remarks
1
0.4 (Ti)
0
0.6
0
0
0
1
0
1
0
B1
2800
850
120
Usual example
2
0.2 (Ti)
0.15
0.65
0
0
0
1
0
1
0
B1
3000
1000
70
Usual example
3
0.2 (Ti)
0.2
0.55
0.05
0
0
1
0
1
0
B1
2900
1100
50
Usual example
4
0
0.4
0.55
0.05
0
0
1
0
1
0
B1
2900
1100
80
Usual example
5
0.45 (Ti)
0.05
0.50
0
0
0
1
0
1
0
B1
2900
1000
90
Usual example
La: 0.001
6
0.35 (Ti)
0
0.60
0.05
0
0.001
1
0
1
0
B1
2800
1100
80
Effect of Y
7
0.15 (Ti)
0.24
0.60
0
0
0.01
1
0
1
0
B1
3200
1100
45
8
0.13 (Ti)
0.24
0.61
0
0
0.02
1
0
1
0
B1
3300
1150
30
9
0.14 (Ti)
0.24
0.57
0
0
0.05
1
0
1
0
B1
3200
1200
30
10
0.14 (Ti)
0.24
0.52
0
0
0.10
1
0
1
0
B1
3200
1150
35
11
0.11 (Ti)
0.24
0.50
0
0
0.15
1
0
1
0
B4
2700
1100
60
12
0.13 (Ti)
0.22
0.60
0.03
0
0.02
1
0
1
0
B1
3300
1250
25
Effect of Si
13
0.14 (Ti)
0.22
0.55
0.07
0
0.02
1
0
1
0
B1
3300
1300
20
14
0.13 (Ti)
0.23
0.50
0.12
0
0.02
1
0
1
0
B1
3250
1300
30
15
0.11 (Ti)
0.17
0.50
0.20
0
0.02
1
0
1
0
B1
3200
1350
45
16
0.10 (Ti)
0.13
0.50
0.25
0
0.02
1
0
1
0
B4
2800
1100
65
17
0.13 (Ti)
0.22
0.61
0
0.02
0.02
1
0
1
0
B1
3250
1250
25
Effect of B
18
0.13 (Ti)
0.22
0.58
0
0.05
0.02
1
0
1
0
B1
3250
1250
25
19
0.13 (Ti)
0.22
0.51
0
0.12
0.02
1
0
1
0
B1
3300
1150
30
20
0.13 (Ti)
0.15
0.50
0
0.20
0.02
1
0
1
0
B4 + B1
3200
1150
45
21
0.10 (Ti)
0.13
0.50
0
0.25
0.02
1
0
1
0
B4
2800
1100
65
22
0.13 (Ti)
0.22
0.58
0.03
0.02
0.02
1
0
1
0
B1
3350
1250
20
Effect of Si and B
23
0.25 (Ti)
0.37
0.35
0
0
0.03
1
0
1
0
B1
2900
1050
55
Effect of Al
24
0.25 (Ti)
0.32
0.40
0
0
0.03
1
0
1
0
B1
3100
1100
30
25
0.20 (Ti)
0.27
0.50
0
0
0.03
1
0
1
0
B1
3200
1250
25
26
0.17 (Ti)
0.20
0.60
0
0
0.03
1
0
1
0
B1
3300
1250
25
27
0.12 (Ti)
0.15
0.70
0
0
0.03
1
0
1
0
B1
3150
1250
30
28
0.07 (Ti)
0.10
0.80
0
0
0.03
1
0
1
0
B4 + B1
3100
1250
45
29
0.05 (Ti)
0.07
0.85
0
0
0.03
1
0
1
0
B4
2800
1250
65
[0000]
TABLE 2
Oxidation
start
Amout
Sample
Hard film (atomic ratio)
Crystal
Hardness
temperature
of wear
No.
M
Cr
Al
Si
B
Y
Sum
C
N
O
structure
(HV)
(° C.)
(μm)
Remarks
30
0.42 (Ti)
0
0.55
0
0
0.03
1
0
1
0
B1
2950
1000
70
Effect of Cr
31
0.32 (Ti)
0.05
0.6
0
0
0.03
1
0
1
0
B1
3100
1250
40
32
0.27 (Ti)
0.1
0.6
0
0
0.03
1
0
1
0
B1
3200
1200
30
33
0.27 (Ti)
0.15
0.55
0
0
0.03
1
0
1
0
B1
3250
1200
25
34
0.17 (Ti)
0.25
0.55
0
0
0.03
1
0
1
0
B1
3200
1150
30
35
0.12 (Ti)
0.4
0.45
0
0
0.03
1
0
1
0
B1
3100
1100
35
36
0.07 (Ti)
0.5
0.4
0
0
0.03
1
0
1
0
B1
2900
1000
85
37
0
0.4
0.57
0
0
0.03
1
0
1
0
B1
2800
1200
80
Effect of M(Ti)
38
0.05 (Ti)
0.35
0.57
0
0
0.03
1
0
1
0
B1
3150
1250
40
39
0.14 (Ti)
0.25
0.58
0
0
0.03
1
0
1
0
B1
3200
1250
30
40
0.2 (Ti)
0.2
0.57
0
0
0.03
1
0
1
0
B1
3300
1200
25
41
0.3 (Ti)
0.12
0.55
0
0
0.03
1
0
1
0
B1
3350
1200
30
42
0.4 (Ti)
0.07
0.5
0
0
0.03
1
0
1
0
B1
3100
1000
67
43
0.15 (Zr)
0.25
0.57
0
0
0.03
1
0
1
0
B1
3150
1150
40
Effect of
44
0.15 (Hf)
0.25
0.57
0
0
0.03
1
0
1
0
B1
3200
1200
30
kind of M
45
0.15 (V)
0.25
0.57
0
0
0.03
1
0
1
0
B1
3250
1100
35
46
0.15 (Nb)
0.25
0.57
0
0
0.03
1
0
1
0
B1
3350
1300
20
47
0.15 (Ta)
0.25
0.57
0
0
0.03
1
0
1
0
B1
3250
1200
30
48
0.15 (Mo)
0.25
0.57
0
0
0.03
1
0
1
0
B1
3250
1150
35
49
0.15 (W)
0.25
0.57
0
0
0.03
1
0
1
0
B1
3250
1150
35
50
0.15 (Ti 0.5 Nb 0.5 )
0.25
0.57
0
0
0.03
1
0
1
0
B1
3300
1250
25
51
0.15 (Hf 0.5 Zr 0.5 )
0.25
0.57
0
0
0.03
1
0
1
0
B1
3250
1200
30
52
0.15 (Ta 0.5 Nb 0.5 )
0.25
0.57
0
0
0.03
1
0
1
0
B1
3300
1250
25
53
0.15 (W 0.5 Hf 0.5 )
0.25
0.57
0
0
0.03
1
0
1
0
B1
3200
1200
30
54
0.15 (Nb)
0.25
0.57
0
0
0.03
1
0
1
0
B1
3350
1250
20
Effect of CNO
55
0.15 (Nb)
0.25
0.57
0
0
0.03
1
0.1
0.9
0
B1
3350
1200
20
56
0.15 (Nb)
0.25
0.57
0
0
0.03
1
0.2
0.8
0
B1
3350
1200
25
57
0.15 (Nb)
0.25
0.57
0
0
0.03
1
0.3
0.7
0
B1
3350
1150
45
58
0.15 (Nb)
0.25
0.57
0
0
0.03
1
0
0.9
0.1
B1
3350
1250
20
59
0.15 (Nb)
0.25
0.57
0
0
0.03
1
0
0.8
0.2
B1
3350
1250
25
60
0.15 (Nb)
0.25
0.57
0
0
0.03
1
0
0.7
0.3
B1
3350
1250
30
61
0.15 (Nb)
0.25
0.57
0
0
0.03
1
0
0.6
0.4
B1
3350
1250
45
[0058] Sample Nos. 6 to 10, 12 to 15, 17 to 20, 22, 24 to 29, 31 to 35, 38 to 41, and 43 to 61 in the Tables 1 and 2 correspond to hard films satisfying requirements specified in an embodiment of the invention, and the hard films are excellent in hardness, oxidation start temperature, wear width and the like compared with usual hard films (Nos. 1 to 5) and hard films varied from the requirements specified in an embodiment of the invention (Nos. 11, 16, 21, 23, 30, 36, 37, 41 and 42).
Example 2
[0059] A target containing Cr. Al, Si, B and Y in various ratios was disposed on the arc evaporation source 6 a of the apparatus (AIP apparatus) shown in FIG. 1 , and a super-alloy tip, a super-alloy boll end mill (10 mm in diameter, two flute) as the bodies to be treated 5 , and a platinum foil for an oxidation test (30 mm in length, 5 mm in width, and 0.1 mm in thickness) were mounted on the rotation tables 3 , then the inside of the vacuum chamber was evacuated into a vacuum. Then, the bodies to be treated 5 were heated to a temperature of 550° C. by the heaters 7 a , 7 b , 7 c and 7 d disposed within the vacuum chamber 1 , and subjected to cleaning using Ar ions (Ar, pressure of 0.6 Pa, voltage of 500 V, and time of 5 min), and then nitrogen gas (N 2 gas) was introduced to increase pressure in the chamber 1 to 4.0 Pa to start arc discharge, consequently hard films 3 μm in thickness were formed on surfaces of the bodies to be treated 5 . When C or O was contained in the film, methane gas (CH 4 gas) or oxygen gas (O 2 gas) was introduced into the deposition apparatus in a range of flow ratio to N 2 gas of 5 to 50 in volume percent. During deposition, a bias voltage of 20 to 100 V was applied to a substrate such that electric potential of the bodies to be treated 5 is negative with respect to ground potential.
[0060] For obtained hard films, metal compositions in the films were measured by EPMA, and Vickers hardness (load of 0.25 N, and holding time of 15 sec) was investigated. Similarly as in the example 1, crystal structures of the films, and characteristics (oxidation start temperature, and wear width) of the films were evaluated.
[0061] Results of them are collectively shown in the following Table 3. It is known that hard films satisfying the requirements specified in an embodiment of the invention (sample Nos. 66 to 69, 71 to 74, 77 to 80, 85 to 87, and 89 to 91) are excellent in hardness, oxidation start temperature, wear width and the like compared with usual hard films (sample Nos. 62 to 65) and hard films varied from the requirements specified in an embodiment of the invention (sample Nos. 70, 75, 76, 81 to 84, and 88).
[0000]
TABLE 3
Sample
Crystal
Hardness
Oxidation start
Amout of
No.
Cr
Al
Si
B
Y
Sum
C
N
O
structure
(HV)
temperature (° C.)
wear (μm)
Remarks
62
0.4
0.6
0
0
0
1
0
1
0
B1
2800
1000
120
Usual example
63
0.4
0.5
0.1
0
0
1
0
1
0
B1
2900
1000
90
Usual example
64
0.4
0.5
0.05
0.05
0
1
0
1
0
B1
2800
1100
80
Usual example
65
0.4
0.58
0
0
0.02
1
0
1
0
B1
2900
1100
80
Usual example
66
0.36
0.6
0.03
0
0.01
1
0
1
0
B1
3100
1250
45
Effect of Y
67
0.34
0.61
0.03
0
0.02
1
0
1
0
B1
3150
1300
31
68
0.35
0.57
0.03
0
0.05
1
0
1
0
B1
3150
1350
31
69
0.35
0.52
0.03
0
0.1
1
0
1
0
B1
3150
1350
32
70
0.32
0.5
0.03
0
0.15
1
0
1
0
B1
2700
1100
60
71
0.35
0.6
0.03
0
0.02
1
0
1
0
B1
3300
1200
25
Effect of Si
72
0.36
0.55
0.07
0
0.02
1
0
1
0
B1
3300
1250
23
73
0.36
0.5
0.12
0
0.02
1
0
1
0
B1
3250
1350
25
74
0.28
0.5
0.2
0
0.02
1
0
1
0
B1
3200
1250
42
75
0.23
0.5
0.25
0
0.02
1
0
1
0
B1
2800
1200
65
76
0.58
0.35
0.04
0
0.03
1
0
1
0
B1
2900
1050
55
Effect of Al
77
0.53
0.4
0.04
0
0.03
1
0
1
0
B1
3100
1300
30
78
0.43
0.5
0.04
0
0.03
1
0
1
0
B1
3200
1300
25
79
0.33
0.6
0.04
0
0.03
0
1
0
B1
3300
1350
24
80
0.23
0.7
0.04
0
0.03
1
0
1
0
B1
3150
1300
26
81
0.13
0.8
0.04
0
0.03
1
0
1
0
B4
2900
1250
70
82
0.08
0.85
0.04
0
0.03
1
0
1
0
B4
2800
1250
85
83
0.1
0.85
0.02
0
0.03
1
0
1
0
B4
2850
1100
80
Effect of Cr
84
0.2
0.7
0.05
0
0.03
1
0.1
0.9
0
B1
3150
1300
45
85
0.25
0.7
0.02
0
0.03
1
0.2
0.8
0
B1
3200
1250
40
86
0.4
0.55
0.02
0
0.03
1
0.3
0.7
0
B1
3100
1350
26
87
0.5
0.45
0.02
0
0.03
1
0
0.9
0.1
B1
2900
1300
27
88
0.6
0.35
0.02
0
0.03
1
0
0.6
0.4
B1
2900
1100
75
89
0.34
0.6
0.03
0.01
0.02
1
0
1
0
B1
3200
1150
27
Effect of Si
90
0.34
0.6
0.02
0.02
0.02
1
0
1
0
B1
3250
1200
25
and B
91
0.33
0.6
0.02
0.03
0.02
1
0
1
0
B1
3150
1200
29
Example 3
[0062] The plurality of arc evaporation sources 6 a , 6 b were installed in the apparatus (AIP apparatus) shown in FIG. 1 , and stacked films including films having compositions as shown in the following Table 4 were formed. At that time, the plurality of targets 6 a , 6 b were simultaneously discharged, and the base materials (bodies to be treated 5 ) were mounted on the rotating rotation tables 3 such that the base materials alternately pass through respective fronts of the arc evaporation sources 6 a , 6 b , thereby the stacked films were formed. For a stacked film having a long stacking period, the arc evaporation sources 6 a , 6 b were alternately discharged to form the stacked film. Other film formation conditions were the same as those in the examples 1 and 2.
[0063] For obtained hard films, metal compositions in the films, Vickers hardness, crystal structures of the films, and characteristics of the films were evaluated in the same way as in the examples 1 and 2.
[0064] Results of them are collectively shown in the following Table 4. It is known that all samples (sample Nos. 92 to 102) are excellent in hardness, oxidation start temperature, wear width and the like.
[0000]
TABLE 4
Layer A
Layer B
Oxidation
Thick-
Thick-
Number
Total
Hard-
start
Amout
Sample
ness
ness
of
thickness
Crystal
ness
temperature
of wear
No.
Kind
(nm)
Kind
(nm)
stacking
(nm)
structure
(HV)
(° C.)
(μm)
92
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.03 )N
2
(Ti 0.17 Cr 0.2 Al 0.5 Si 0.1 Y 0.0 3)N
2
750
3000
B1
3200
1250
30
93
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.03 )N
5
(Ti 0.17 Cr 0.2 Al 0.5 Si 0.1 Y 0.0 3)N
5
300
3000
B1
3300
1250
25
94
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.03 )N
20
(Ti 0.17 Cr 0.2 Al 0.5 Si 0.1 Y 0.0 3)N
20
75
3000
B1
3350
1250
20
95
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.03 )N
50
(Ti 0.17 Cr 0.2 Al 0.5 Si 0.1 Y 0.0 3)N
50
30
3000
B1
3350
1250
20
96
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.03 )N
150
(Ti 0.17 Cr 0.2 Al 0.5 Si 0.1 Y 0.0 3)N
150
10
3000
B1
3250
1250
25
97
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.03 )N
200
(Ti 0.17 Cr 0.2 Al 0.5 Si 0.1 Y 0.0 3)N
200
7
2800
B1
3200
1250
30
98
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.03 )N
300
(Ti 0.17 Cr 0.2 Al 0.5 Si 0.1 Y 0.0 3)N
300
5
3000
B1
3150
1250
35
99
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.03 )N
30
(Nb 0.1 Cr 0.2 Al 0.55 Si 0.1 Y 0.05 )N
30
50
3000
B1
3250
1250
20
100
(Ti 0.5 Al 0.5 )N
1500
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.0 3)N
1500
1
3000
B1
3200
1150
40
101
(Ti 0.25 Cr 0.1 Al 0.65 )N
2000
(Ti 0.2 Cr 0.2 Al 0.57 Y 0.0 3)N
1000
1
3000
B1
3250
1200
35
102
(Nbl 0.15 Cr 0.25 Al 0.6 )N
20
(Ti 0.17 Cr 0.2 Al 0.5 Si 0.1 Y 0.0 3)N
20
75
3000
B4
3300
1250
25 | Disclosed are a hard film and a method useful for manufacturing the hard film wherein the hard film is obviously excellent in wear resistance, and exhibits excellent oxidation resistance even under a condition where hot heat generation tends to occur due to friction heating, consequently exhibits excellent properties compared with a usual hard-film including TiAlN, TiCrAlN, TiCrAlSiBN, CrAlSiBN, or NbCrAlSiBN. The hard film includes (M) a Cr b Al c Si d B e Y f Z (however, M is at least one element selected from a group 4A element, a group 5A element, and a group 6A element (except for Cr) in the periodic table, and Z shows one of N, CN, NO and CNO), wherein
a+b+c+d+e+f=1, and 0≦a≦0.3, 0.05≦b≦0.4, 0.4≦c≦0.8, 0≦d≦0.2, 0≦e≦0.2, and 0.01≦f≦0.1, (a, b, c, d, e and f show atomic ratios of M, Cr, Al, Si, B and Y respectively). | 8 |
BACKGROUND OF THE INVENTION
This invention relates to a method of treating human skin and more particularly is directed to the alleviation of acne by applying to the infected area a mixture of an antimicrobial agent and a volatile cyclic silicone. The mixture is delivered to the skin by entrapping the mixture within particles of a hydrophobic macroporous highly cross-linked polymer.
The concept of producing spheres and beads of a macroporous polymer is old in the art as is the use of such macroporous structures for the entrapment and subsequent delivery of certain active ingredients. One example of this concept may be found in U.S. Pat. No. 4,690,825 issued Sep. 1, 1987 in which a suspension polymerization process is employed to produce beads from a monomer system including styrene and divinylbenzene. Mineral oil is entrapped "in situ" and the beads are stated to possess utility in various cosmetic applications. In U.S. Pat. No. 4,719,040 issued Jan. 12, 1988 a macroporous polymer laden with perfume is incorporated into an air freshener gel. U.S. Pat. No. Re. 33,429 issued Nov. 6, 1990; European Patent 61,701 granted Jul. 16, 1986; and Canadian Patent 1,168,157 issued May 29, 1984; each relate to "in situ" entrapped moisturizers carried within macroporous beads. Various cosmetic and toiletry applications of these products are also disclosed.
A macroporous polymer entrapping an emollient is taught in U.S. Pat. No. 4,764,362 issued Aug. 16, 1988 and in U.S. Pat. No. 4,813,976 issued Mar. 21, 1989, in which the polymer is incorporated into a nail conditioning emery board. During filing of the nails, the emollient is released in order to condition and lubricate the nails. A similar concept is taught in U.S. Pat. No. 4,776,358 issued Oct. 11, 1988 in which a dental floss includes flavor oils entrapped in certain "microsponges". Suspension polymerized macroporous polymer beads are taught in U.S. Pat. No. 4,806,360 issued Feb. 21, 1989 and in U.S. Pat. No. 4,855,144 issued Aug. 8, 1989, wherein melanin pigment is incorporated into the macroporous structure and applied to the skin to function as a sunscreen. Similar bead structures are also taught in European application 306 236 published Mar. 3, 1989 and in Patent Cooperation Treaty International application WO 88/01164 published Feb. 25, 1988. Beads carrying a cationic charge in order to improve the adhesion to hair and skin are described in European application 369 741 published May 23, 1990.
A reticulated polyurethane foam is disclosed in U.S. Pat. No. 4,828,542 issued May 9, 1989 having macroporous polymer particles bonded to the foam. The particles entrap a liquid soap and the foam functions as a cleaning pad. In U.S. Pat. No. 4,855,127 issued Aug. 8, 1989 and U.S. Pat. No. 4,880,617 issued Nov. 14, 1989, hydrophobic polymeric porous beads are used as a free-flowing solid carrier for various pheromones, pesticides, fragrances and chemicals entrapped therein. Hydrophilic beads are formed in U.S. Pat. No. 4,870,145 issued Sep. 26, 1989 and upon removal of the solvent used to form voids, the beads possess various utilities such as incorporation into contact lens cleaners, facial scrubs and tile cleaners. In U.S. Pat. No. 4,873,091 issued Oct. 10, 1989 resilient microbeads are formed by suspension polymerizing curable elastomers such as isoprene rubbers to produce porous rubber beads. The porous rubber beads are employed in topical applications. In the Patent Cooperation Treaty International application WO89/10132 published Nov. 2, 1989 porous particles are disclosed as an ingredient in personal care emulsions. A pet litter is described in U.S. Pat. No. 4,881,490 issued Nov. 21, 1989 and U.S. Pat. No. 4,883,021 issued Nov. 28, 1989, wherein a macromolecular polymer entrapping a fragrance is incorporated into an animal litter to slowly release fragrance for combating odors.
In U.S. Pat. No. 4,898,913 issued Feb. 6, 1990 macroporous hydrophobic powder materials are rendered hydrophilic by treatment of the surface of the powder. In one embodiment of the '913 patent, the surface is saponified whereas in another embodiment an acrylate monomer is polymerized on the surface. A wet wipe useful in personal care applications is disclosed in U.S. Pat. No. 4,904,524 issued Feb. 27, 1990 wherein macroporous polymeric beads containing a silicone skin conditioner are incorporated into the surface of a paper sheet. Polymeric microparticles loaded with a fungicide are taught in U.S. Pat. No. 4,923,894 issued May 8, 1990. In U.S. Pat. No. 4,933,372 issued Jun. 12, 1990 there is described rigid resin particles formed by polymerizing monounsaturated and polyunsaturated monomers within the pores of inorganic template particles such as silica gel, silica, alumina, zirconia and metal oxides. The template particles are dissolved leaving porous adsorptive particles which mirror the template particles in size, surface area and porosity. Macroporous particles capable of adsorbing hydrophilic as well as lipophilic fluids are taught in U.S. Pat. No. 4,948,818 issued Aug. 14, 1990. Similar materials can be provided in bulk form as polymerized plugs containing entrapped pheromones in accordance with apparatus described in U.S. Pat. No. 4,958,999 issued Sep. 25, 1990. A fragrance dispenser device in the shape of an hourglass containing reticulate particulates entrapping an aroma chemical is depicted in U.S. Pat. No. 4,961,532 issued Oct. 9, 1990. In U.S. Pat. No. 4,962,133 issued Oct. 9, 1990 a process for producing macroporous particulates is described including the the inclusion of an azeotrope to enable an inorganic initiator to be employed. The '133 patent also contains a review of the prior art, a comprehensive list of the uses of such materials, and functional and active ingredients which may be entrapped therein. Similar materials produced by polymerizing only polyunsaturated monomers are set forth in U.S. Pat. No. 4,962,170 issued Oct. 9, 1990.
In accordance with the present invention however, a new and novel combination including such materials as a carrier has been discovered wherein provision is made for excess skin oil adsorption into the materials in addition to contact of the skin with entrapped acne treatment ingredients. The macroporous particles have been found to function as a skin oil absorbent when delivered in combination with a volatile cyclic silicone and an antimicrobial agent.
SUMMARY OF THE INVENTION
The invention is directed to a method of treating skin disorders by applying topically to the skin a mixture of an antimicrobial agent and a volatile low viscosity organosilicon compound. The mixture is entrapped within and dispersed uniformly throughout discrete particles of a hydrophobic macroporous highly crosslinked polymer. The particles are spread on the skin in order to release the mixture while allowing the volatile low viscosity organosilicon compound to evaporate. Excess skin oil such as sebum is adsorbed from the skin and into the macroporous polymer. The invention is also directed to a composition which is a mixture of the antimicrobial agent and the volatile cyclic silicone entrapped withing the polymer particles.
These and other objects, features, and advantages, of the present invention will become apparent when considered in light of the following detailed description including the accompanying drawings.
IN THE DRAWINGS
FIG. 1 is a photomicrograph showing the individual components of the complex structure of the macroporous powder which is produced by the precipitation polymerization process of Example I. There is illustrated the unit particles, agglomerates and aggregates which make up the powder.
FIG. 2 is a photomicrograph of a single agglomerate of FIG. 1 but showing the agglomerate on an increased scale.
FIG. 3 is a photomicrograph of a single aggregate of FIG. 1 but showing the aggregate on an increased scale.
FIG. 4 is a photomicrograph of a single polymer bead produced by the suspension polymerization process of Example III.
FIG. 5 is a photomicrograph of the bead of FIG. 4 but on an increased scale. The bead has a portion of its porous outer layer removed to reveal the interior macroporous structure of the bead.
Each figure indicates in the upper left hand corner the magnification employed in producing the photomicrograph.
DETAILED DESCRIPTION OF THE INVENTION
As should be apparent from a consideration of FIGS. 1-3, one embodiment of the polymeric material of the present invention is macroporous because of its complex arrangement of unit particles, agglomerates and aggregates. As a result of this complex structure the material possesses an inordinate proportion of interstitial space and is a labyrinth of voids. Volatile ingredients entrapped within the void volume of the material are released by wicking to the surface and evaporate at a rate dependent upon such factors as temperature, vapor pressure and surface area. Nonvolatile ingredients migrate to the surface by means of capillary action and are released on contact with another surface. Mechanical disruption may also be used to release an entrapped ingredient. While the material is shear sensitive it is not compression sensitive. The materiaal is capable of wicking ingredients from another surface in the fashion of a sponge. The material does not shrink or expand even though it is capable of adsorbing several times its own weight of an active ingredient. Since the process involved is adsorption in contrast to absorption, the properties of both the material and the active ingredient are not altered. Active ingredients are entrapped within the material in contrast to being encapsulated. Encapsulation connotes a complete enclosing of one material within another such as a shell formed around a core of liquid. Encapsulated ingredients are released by mechanical disruption of the shell or dissolution of the shell, and once the shell is disrupted the entire contents of the shell are extracted. With entrapment however the release of the entrapped ingredient is controlled or sustained by wicking, evaporation and capillary action. In addition the active ingredient is permitted a relatively unobstructed ingress and egress into and out of the labyrinth of voids.
The hydrophobic macroporous material of the present invention can be generically described as a crosslinked polymer in particulate form capable of entrapping solids and liquids. The particles are free flowing and discrete particulates even when loaded with an active ingredient. One polymer representative of the materials in accordance with the present invention has the formula: ##STR1## wherein the ratio of x to y is 80:20, R' is --CH 2 CH 2 --, and R" is --(CH 2 ) 11 CH 3 .
This polymeric material is highly crosslinked and is a polymethacrylate. The material is manufactured by the Dow Corning Corporation, Midland, Mich. and sold under the trademark POLYTRAP. It is a low density, highly porous free-flowing white particulate. The particles are capable of adsorbing high levels of lipophilic liquids and some hydrophilic liquids while at the same time maintaining a free-flowing particulate character. The polymer can be formed by polymerizing a single polyunsaturated monomer such as ethylene glycol dimethacrylate or tetraethylene glycol dimethacrylate. Such a process is described in U.S. Pat. No. 4,962,170 issued Oct. 9, 1990 which is incorporated herein by reference. The polymer may also be formed by polymerizing two monomers including a polyunsaturated monomer and a monounsaturated monomer such as lauryl methacrylate or 2-ethylhexyl methacrylate.
Depending upon which process for making the material is employed, the polymer particles can be in the form of a bead having an average diameter of about ten microns to about one hundred-fifty microns, or alternatively the polymer can be in the form of a powder. The powder form is best defined as a combined system of particles. The system of powder particles includes unit particles of less than about one micron in average diameter, agglomerates of many fused unit particles of sizes in the range of about twenty to eighty microns in average diameter, and aggregates of clusters of many fused agglomerates of sizes in the range of about two-hundred to about twelve-hundred microns in average diameter. Whether the polymer is in the form of a spherical macroporous bead or in the form of the complex macroporous powder, the structure is adapted to contain entrapped active materials depending upon the application.
A precipitation polymerization process is one method for producing the macroporous cross-linked polymer. In the process there is polymerized one monounsaturated monomer and one polyunsaturated monomer in the presence of an excess of a volatile organic liquid which is a solvent for the monomers but not for the polymer. Polymerization of the monomers is initiated by means of a free radical generating catalytic compound which precipitates a polymer in the solvent in the form of a powder structure. A dry powder is formed by removing the volatile solvent from the precipitated polymeric powder leaving a structured submicron sized adsorbent. The most preferred solvent is isopropyl alcohol although other solvents such as ethanol, toluene, heptane, xylene, hexane, ethyl alcohol and cyclohexane may also be employed. The monounsaturated monomer and the polyunsaturated monomer can be present in various mole ratios such as 20:80, 30:70, 40:60, or 50:50. The process includes the step of stirring the monomers, solvent and the free radical generating catalytic compound during polymerization. The powder is dried by filtering excess solvent from the precipitated powder and the filtered powder is vacuum dried. The empty powder may be used in its dry form in some applications or it can be formulated by "post adsorbing" the empty powder with various functional materials.
Adsorption of active ingredients can be accomplished using a stainless steel mixing bowl and a spoon. The active ingredient is added to the empty dry powder and the spoon is used to gently fold the active into the powder. Low viscosity fluids may be adsorbed by addition of the fluids to a sealable vessel containing the powder and tumbling the materials until the desired consistency is achieved. More elaborate blending equipment such as ribbon or twin cone blenders can also be employed.
The following example illustrates one method of making an adsorbent powder of the type illustrated in FIGS. 1-3.
EXAMPLE I
A hydrophobic porous polymer was produced in a five hundred milliliter reactor equipped with a paddle type stirrer by mixing 13.63 grams of ethylene glycol dimethacrylate monomer or eighty mole percent and 4.37 grams of lauryl methacrylate monomer or twenty mole percent. Isopropyl alcohol was added to the reactor as the volatile solvent in the amount of 282 grams. The monomers were soluble in the solvent but not the precipitated polymer. The process can also be conducted using one polyunsaturated monomer as noted above. The mixture including the monomers, solvent and 0.36 grams of the catalytic initiator benzoyl peroxide was purged with nitrogen. The system was heated with a water bath to sixty degrees Centigrade until polymerization was initiated and the temperature was increased to 70-75 degrees for six hours to complete polymerization. During this time the polymer precipitated from the solution. The polymerization produced unit particles of a diameter less than about one micron. Some of the unit particles adhered and fused together forming agglomerates about twenty to eighty microns in diameter. Some of the agglomerates adhered and fused together forming aggregates of loosely held assemblies of agglomerates about two hundred to twelve hundred microns in diameter. The mixture was filtered to remove excess solvent and a wet powder cake was tray dried in a vacuum oven. A dry hydrophobic polymeric powder consisting of unit particles, agglomerates and aggregates was isolated.
The method of Example I is a precipitation polymerization technique. In accordance with this technique monomers are dissolved in a compatible volatile solvent in which both monomers solubilize. Polymer in the form of a powder is precipitated and the polymer is insoluble in the solvent. No surfactant or dispersing aid is required. The materials produced are randomly shaped particles and not spheres or beads. The randomly shaped powder particulates include unit particles, agglomerates and aggregates. The volatile solvent is removed leaving an empty dry powder. The empty dry powder is suitable for use in an active-free condition for some applications or it may be "post adsorbed" with a variety of functional active ingredients for other applications.
Some unique features of the powder of Example I and FIGS. 1-3 is its ability to adsorb liquids and yet remain free flowing. The material provides a regulated release of ingredients entrapped therein and has the capability of functioning as a carrier. The powders disappear when rubbed upon a surface. This phenomenon is due to the fact that large aggregates of the material scatter light rendering the appearance of a white particulate but when rubbed, these shear sensitive large aggregates decrease in size approaching the range of visible light and seem to disappear. The materials possess utility in many diverse areas such as the cosmetics and toiletries industry, household and industrial applications, agriculture as pesticide and pheromone carriers, and pharmaceuticals applications.
The following example illustrates another precipitation polymerization process in which an organic ester is entrapped "in situ" in the polymer. No volatile solvent is employed in Example II. The ester remains entrapped in accordance with this example.
EXAMPLE II
Seven grams of the ester 2-ethylhexyl oxystearate was mixed with 1.5 grams of ethylene glycol dimethacrylate and 1.5 grams of lauryl methacrylate in a glass test tube. The solution was deaerated for five minutes and 0.1 milliliters of t-butyl peroctoate was added and mixed while heating to eighty degrees Centigrade in an oil bath. After twenty minutes the contents of the glass test tube solidified and the mixture was maintained at the same temperature for an additional hour to assure full polymerization. A heterogeneous white polymer resulted containing the entrapped ester.
The powder product of Example I differs from the product of Example II in that a volatile solvent is used in Example I and the solvent is removed which results in a dry empty powder free of active ingredients. In Example II a non-volatile functional material is polymerized "in situ" and the active ingredient remains entrapped in the powder product.
In contrast to either of the previous examples, suspension polymerization is a process which is carried out in water. The monomers, active ingredient and the catalyst are combined and form beads or droplets in water and polymerization occurs within each bead. A surfactant and stabilizer such as polyvinyl pyrrolidone is required to prevent individually formed beads and droplets from coalescing. The resulting beads with the active material entrapped have a substantially spherical outer crust or shell and an interior macroporous structure. The bead is about ten to one hundred-fifty microns in average diameter depending upon the rate of agitation employed during the process.
Example III illustrates a process for the production of beads by suspension polymerization in which an organic ester is entrapped "in situ" within the beads.
EXAMPLE III
Into a two liter three necked flask equipped with a stirrer, thermometer and a nitrogen purge 1.2 grams of polyvinyl pyrrolidone was dissolved in 1500 milliliters of water. A solution of 335 grams of 2-ethylhexyl oxystearate ester, 132 grams of ethylene glycol dimethacrylate, thirty-three grams of 2-ethylhexyl methacrylate and five milliliters of t-butyl peroctoate was bubbled with nitrogen for five minutes. This mixture was slowly added to the stirred aqueous solution of polyvinyl pyrrolidone at twenty-two degrees Centigrade under nitrogen purge. The temperature was raised to eighty degrees with constant agitation and maintained for fifteen minutes until polymerization initiated. The temperature remained at eighty degrees for an additional two hours to complete the reaction. White beads were collected by filtering off supernatant liquid and the beads were dried to remove any excess water. The beads weighed 450 grams providing a yield of ninety percent and were 0.25 to 0.5 millimeters in average diameter. Beads of this type are shown in FIGS. 4 and 5. Other protective colloids such as starch, polyvinyl alcohol, carboxymethyl cellulose, methyl cellulose or inorganic divalent alkali metal hydroxides such as MgOH may be used in place of polyvinyl pyrrolidone.
In Example III macroporous polymers submicron in size are produced and polymerization is conducted in the presence of an active ingredient which does not dissolve or swell the resulting polymer. The monomers and the active ingredient are mutually soluble but insoluble in the aqueous suspending medium in which droplets are formed. Polymerization occurs within the suspended droplets and beads or spheres are produced. The active ingredient which is polymerized "in situ" is entrapped and contained within the beads but the active ingredient is capable of being released. A volatile solvent or porogen can be substituted for the active ingredient and removed leaving an empty porous polymer bead product free of "in situ" entrapped active materials.
Examples of polyunsaturated monomers which may be employed are ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane ethoxylated triacrylate, ditrimethylolpropane dimethacrylate; propylene, dipropylene and higher propylene glycols; 1,3 butylene glycol dimethacrylate; 1,4 butanediol dimethacrylate; 1,6 hexanediol dimethacrylate, neopentyl glycol dimethacrylate, pentaerythritol dimethacrylate, dipentaerythritol dimethacrylate, bisphenol A dimethacrylate, divinyl and trivinylbenzene, divinyl and trivinyltoluene, triallyl maleate, triallyl phosphate, diallyl maleate, and diallyl itaconate.
Monounsaturated monomers include methacrylates and acrylates having straight or branched chain alkyl groups with 1 to 30 carbon atoms preferably 5 to 18 carbon atoms. Preferred monomers are lauryl methacrylate, 2-ethylhexyl methacrylate, isodecylmethacrylate, stearyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, diacetone acrylamide, phenoxyethyl methacrylate, tetrahydrofurfuryl methacrylate and methoxyethyl methacrylate. Additional suitable monomers can be found in many of the patents referred to in the Background section. Highly crosslinked polymeric systems consisting of particles of submicron size can be prepared from only monomers having at least two polymerizable unsaturated bonds and containing no comonomers having monounsaturated moiety as taught in U.S. Pat. No. 4,962,170.
Removal of some entrapped ingredients has been accomplished surprisingly by mechanical means utilizing an unexpected phenomenon of the adsorbent that the powder material, while being shear sensitive, is not compressive sensitive. Thus it has been possible to apply compressive forces generated by a pair of stainless steel surfaces to the laden adsorbent powder to squeeze out and remove an active entrapped ingredient. The compressive forces have not been found to cause a degenerative effect upon the resulting adsorbent powder. During laboratory assimilations of compressive forces utilizing two stainless steel disks and a vice, the powder adsorbent has been sifted to break up any compacted powder masses followed by squeezing out of the entrapped active ingredient.
The volatile low viscosity organosilicon compound contemplated in accordance with the present invention includes cyclic silicone fluids and linear silicones. Representative of these materials are polydimethylcyclosiloxane and hexamethyldisiloxane. Such fluids have viscosities of 0.65 to 5.0 centistokes measured at twenty-five degrees Centigrade.
The volatile cyclic silicones generally conform to the formula (R 2 SiO) x in which R is an alkyl radical having from one to three carbon atoms or a phenyl group. Most typically the cyclic siloxanes have the formula [(CH 3 ) 2 SiO] x in which x is an integer from three to ten. Some volatile cyclic siloxane compounds found to be especially useful in accordance with the present invention are the tetramer compound octamethylcyclotetrasiloxane and the pentamer compound decamethylcyclopentasiloxane. Mixtures of the tetramer and pentamer may also be employed. Such cyclic siloxanes have viscosities ranging from about 2.5 centistokes to about five centistokes. These materials are also known under The Cosmetics, Toiletries and Fragrance Association designation as cyclomethicone.
The volatile low viscosity linear silicone fluids have the formula R 3 SiO(R 2 SiO) n SiR 3 in which R is an alkyl radical having one to six carbon atoms and n is an integer of from two to nine. Most representative of this class of linear siloxane is hexamethyldisiloxane of the formula ##STR2## which has a viscosity of 0.65 centistokes measured at twenty-five degrees Centigrade.
Both the cyclic and linear low viscosity volatile silicones are clear fluids and are essentially odorless, nontoxic, nongreasy and nonstinging. Cosmetically they are nonirritating to the skin and possess the properties of good spreadability and ease of rub-out. The materials evaporate leaving behind no residue.
The antimicrobial agent which is most suitable is an antibacterial compound such as benzoyl peroxide, salicyclic acid or resorcinol which are known for their ability to alleviate the acne problem to one degree or another. The mixture of the antimicrobial agent and the volatile low viscosity organosilicon compound should preferably be in the weight ratio of 50:50 to 70:30 antimicrobial agent to organosilicon compound. The following additional examples illustrate the skin treatment method and composition contemplated in accordance with the present invention.
EXAMPLE IV
Forty weight percent of benzoyl peroxide and forty weight percent of volatile cyclic silicone were combined. The volatile cyclic silicone was a mixture of the tetramer compound octamethylcyclotetrasiloxane and the pentamer compound decamethylcyclopentasiloxane. The mixture of the tetramer and pentamer had a viscosity of five centistokes and included seventy-five percent of the tetramer and twenty-five percent of the pentamer. The benzoyl peroxide and volatile cyclic silicone mixture was ground with a mortar and pestle until a suspension of finely dispersed benzoyl peroxide was produced. The benzoyl peroxide suspension was combined and blended with twenty weight percent of the macroporous polymer powder of Example I until there was produced a uniform free flowing powder. The free flowing powder was applied to the facial skin of volunteers. Following the elapse of thirty to sixty minutes after the application of the free flowing powder, a very slight whiteness was noted to appear on the skin.
The volunteers indicated that the free flowing powder had rubbed out smoothly and easily onto the skin. The test site on the skin of the volunteers remained non-oily for upwards of three hours following application of the free flowing powder indicating that as the volatile cyclic silicone evaporated and as the antimicrobial agent was slowly released from the free flowing powder, excess oil produced by the skin was adsorbed by the macroporous polymer powder which remained on the skin. This is significant in that acne treatment is enhanced by prevention of buildup on the skin of excess sebum. The presence of the volatile cyclic silicone additionally contributes the benefit of enabling a cosmetically acceptable product to be formulated and provides the characteristic good spreadability and ease of rubout of the formulation. A dry silky feel is left to the skin as the volatile cyclic silicone evaporates. Unlike organic volatile carrier materials, the volatile cyclic silicones do not cool the skin as they evaporate.
While European application 306236 published Mar. 8, 1989 refers to porous beads containing benzoyl peroxide or salicylic acid, it does not disclose the combination with a volatile cyclic silicone and the attendant benefits of employing the silicones as noted above.
EXAMPLE V
Example IV was repeated except that salicyclic acid was used as the antimicrobial agent. The results were the same as indicated in Example IV.
EXAMPLE VI
Example IV was repeated except that fifty-five weight percent of benzoyl peroxide and twenty-five weight percent of the volatile cyclic silicone were employed. The results were the same as indicated in Example IV.
It will be apparent from the foregoing that many other variations and modifications may be made in the compounds, compositions, and methods described herein without departing substantially from the essential features and concepts of the present invention. Accordingly, it should be clearly understood that the forms of the invention described herein are exemplary only and are not intended as limitations of the scope on the present invention. | A method of treating skin disorders such as acne by applying topically to the infected area a mixture of an antimicrobial agent and a volatile low viscosity organosilicon compound. The mixture is entrapped within and dispersed uniformly throughout discrete particles of a hydrophobic macroporous highly crosslinked polymer. The particles are spread on the skin releasing the mixture while allowing the volatile low viscosity organosilicon compound to evaporate. Excess skin oil such as sebum is simultaneously adsorbed from the skin and into the macroporous polymer. | 0 |
FIELD OF THE INVENTION
The present invention relates to breathable absorbent articles like baby diapers, adult incontinence articles and in particular to sanitary napkins or pantiliners. According to the present invention the articles are provided with an apertured backsheet for breathability. At least one of the breathable layers of the backsheet comprises a resilient, three dimensional web which consists of a liquid impervious polymeric film having apertures. The apertures form capillaries which are not perpendicular to the plane of the film but are disposed at a angle of less than 90° relative to the plane of the film.
BACKGROUND OF THE INVENTION
The primary consumer needs which underlie development in the absorbent article field, in particular sanitary napkins, catamenials, or pantiliners is the provision of products providing both a high protection and comfort level.
One means for providing consumer comfort benefits in absorbent articles is by the provision of breathable products. Breathability has typically concentrated on the incorporation of so called ‘breathable backsheets’ in the absorbent articles. Conmmonly utilised breathable backsheets are microporous films and apertured formed films having directional fluid transfer as disclosed in for example U.S. Pat. No. 4,591,523. Both these types of breathable backsheets are vapour permeable allowing gaseous exchange with the environment. This thereby allows for the evaporation of a portion of the fluid stored in the core and increases the circulation of air within the absorbent article. The latter is particularly beneficial as it reduces the sticky feeling experienced by many wearers during use, commonly associated with the presence of an apertured formed film or film like topsheet.
A drawback associated with the use of breathable backsheets in absorbent articles is the negative effect on the protection level performance by leakage, known as wet through, onto the users garment. Although, breathable backsheets in principle only allow the transfer of materials in the gaseous state, physical mechanisms such as extrusion, diffusion and capillary action may still occur and result in the transfer of the fluids from the absorbent core through the backsheet and onto the users garments. In particular, these mechanisms become more dominant if the product is utilised during physical exertion, or for heavy discharge loads or over extended periods of time. Thus, whilst the incorporation of breathable backsheets in absorbent articles is highly desirable from a comfort standpoint, since the primary role of a backsheet still remains the prevention of liquid leakage, conventional breathable backsheets have not been satisfactorily incorporated into products.
The problem of wet through onto users garments due to the incorporation of such breathable backsheets in absorbent articles has indeed also been recognized in the art. Attempts to solve the problem have mainly resided in the use of multiple layer backsheets such as those illustrated in U.S. Pat. No. 4,341,216. Similarly European patent application no. 710 471 discloses a breathable backsheet comprising an outer layer of a gas permeable, hydrophobic, polymeric fibrous fabric and an inner layer comprising an apertured formed film having directional fluid transport. The backsheet construction preferably has no liquid transport/wet through under certain specified test conditions. Also European patent application no. 710 472 discloses a breathable backsheet consisting of at least two breathable layers which are unattached to one another over the core area. The backsheet construction preferably has no liquid transport/wet through under certain specified test conditions.
U.S. Pat. No. 4,713,068 discloses a breathable clothlike barrier for use as an outer cover for absorbent articles. The barrier comprises at least 2 layers, a first layer having a specified basis weight, fiber diameter and pore size and a second layer comprising a continuous film of poly (vinyl alcohol) having a specified thickness. The barrier also has a specified water vapour transmission rate and level of impermeability.
However, none of the above proposed solutions have been able to provide a fully satisfactory solution to the problem of breathable backsheet wet through under all conditions.
U.S. Pat. No. 5,591,510 as well as WO 97/03118 and WO 97/03795 disclose an apertured film layer having capillaries which are disposed at an angle relative to the plain of the film, which films are referred to as slanted capillary films. This film structure is provided as a improvement for incorporation into clothing and garments which are breathable, yet non transmitting liquids toward the wearer of such garments. Also the use of such slanted capillary films is indicated in the context of absorbent articles but as a topsheet, particularly in FIG. 16 of U.S. 5,591,510 the combination of such slanted capillary films together with an absorbent material is disclosed, however not in the context of disposable absorbent articles according to the present invention.
It is therefore an objective of the present invention to provide a disposable absorbent article having improved comfort while maintaining an acceptable level of protection, i.e. being exceptionally leakage resistant.
SUMMARY OF THE INVENTION
The present invention relates to breathable disposable absorbent articles of a layered construction such as baby diapers, adult incontinence articles and in particular sanitary napkins or panty liners. Also articles such as underarm sweat pads or shirt scholars may benefit from the present invention. Typically such articles are of layered construction with each layer or group of layers having a garment facing surface which is oriented to face in the direction of a garment during use of the article and a wearer facing surface facing in the opposite direction. Typically such articles comprise a liquid pervious topsheet forming the wearer facing surface of the article, an absorbent core and a breathable backsheet forming the garment facing surface of the article. The absorbent core is interposed between the topsheet and the backsheet. However, according to the present invention the absorbent core may provide the wearer facing surface of the article such that this surface of the core also provides the functions of the topsheet.
The breathable backsheet is located on the garment facing surface of the absorbent core and comprises at least a first backsheet layer and a second backsheet layer. The first backsheet layer is positioned between the garment facing surface of the absorbent core and the wearer facing surface of the second backsheet layer. In order to provide the article with breathability all backsheet layers are at least water vapor permeable, preferably air permeable. The first backsheet layer comprises a resilient three dimensional web, which consists of a liquid impervious polymeric film which film has apertures. The apertures form capillaries which have side walls which extend away from the wearer facing surface of the film providing the web with three dimensionality. The capillaries have a first opening in the garment facing surface of the film and a second opening at the end of the capillaries spaced apart from the wearer facing surface of the film. Importantly the capillaries extend away from the wearer facing surface of the film at an angle which is less than 90° in respect to the plain of the film.
In a preferred embodiment the capillaries are all substantially identical and preferably are homogeneously distributed across the film. Preferably a center axis of each capillary forms an angle between 85° and 20°, more preferably between 65° and 25° and most preferably between 55° and 30° with the plain of the film. The center axis is defined as the line which connects the center point of the first opening of a capillary and the center point of the second opening of a capillary.
For some embodiments it is also possible that the first opening of at least some of the capillaries is larger than the second opening of the respective capillary such that the capillaries themselves form cones which have an increase in capillary action in a direction towards the absorbent core. In yet another embodiment according to the present invention the capillaries are curved towards or appear bent towards the plain of the film. In an alternative or in addition thereto the capillaries have a first and a second portion which are different in direction, form, shape, size or combinations thereof.
Also the second opening of at least some of the capillaries may be provided as slits. Slits are considered to be such forms in which the longest extend of an opening is at least 5 times the length of the smallest length of the opening.
In general the construction of the absorbent article can be such that the web comprising the film forms the wearer facing surface of the backsheet construction. In this way the directional liquid transport and the ability to close under pressure derivable from the angled capillaries provide the best leak through protection while maintaining optimum breathability for improved comfort.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross-sectional view of an absorbent article comprising all usual elements of such articles including an embodiment of the breathable backsheet according to the present invention.
FIGS. 2-7 show particular alternative embodiments of the slanted capillaries used for the three dimensional web comprised in the breathable backsheet according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to absorbent disposable articles such as sanitary napkins, panty liners, incontinence products sweatpads and baby diapers. Typically such products comprise the elements of a liquid pervious topsheet, a backsheet and an absorbent core intermediate said topsheet and said backsheet. According to the present invention the topsheet, backsheet and core may be selected from any of the known types of these components provided that they meet the desired comfort and protection performance requirements and conditions noted below and in the apended claims.
In general, the topsheet—if present—should have good liquid retention to maintain a dry surface and thereby keep the skin of the wearer dry; the absorbent core needs to provide enough absorbent capacity and allow the flow of vapour and/or air through it and the backsheet should prevent wet through (liquid permeability) to retain the absorbed fluid while being sufficiently breathable. Furthermore, the individual elements are joined, preferably using techniques such that the final product has the desired comfort and performance level.
In the following description of the invention the surface facing in the direction of the wearer is called wearer facing surface. In the drawings this direction is indicated by arrow 20 . Further the surface facing in the direction of the garment is called garment facing surface and in the drawings this direction is indicated by arrow 21 .
Absorbent Article Components
The Topsheet
According to the present invention the absorbent article usually comprises a topsheet. The topsheets suitable for use herein may be any topsheet known in the art. In FIG. 1 the topsheet is indicated with reference numeral 30 .
The topsheets for use herein may comprise a single layer or a multiplicity of layers. In a preferred embodiment the topsheet comprises a first layer which provides the user facing surface of the topsheet and a second layer between the first layer and the absorbent structure/core. In addition another layer on the wearer facing surface of the first layer but only extending in the central zone or in parts of the peripheral zone of the article can be desirable to provide extra softness or extra liquid handling/retaining abilities (this design is usually referred to as “hybrid topsheet”). The topsheet typically extends across the whole of the absorbent structure and can extend into and form part of or all of the preferred sideflaps, side wrapping elements or wings.
The topsheet as a whole and hence each layer individually needs to be compliant, soft feeling, and non-irritating to the wearer's skin. It also can have elastic characteristics allowing it to be stretched in one or two directions. As used herein the topsheet hence refers to any layer or combination of layers whose principle function is the acquisition and transport of fluid from the wearer towards the absorbent core and containment of the absorbent core. In addition the topsheet of the present invention should have a high vapour permeability preferably also a high air permeability.
According to the present invention the topsheet may be formed from any of the materials available for this purpose and known in the art, such as wovens, non wovens, films or combinations thereof. In a preferred embodiment of the present invention at least one of the layers of the topsheet comprises a liquid permeable apertured polymeric film. Preferably, the wearer facing and contacting layer is provided by a film material having apertures which are provided to facilitate liquid transport from the wearer facing surface towards the absorbent structure, as detailed for example in U.S. Pat. Nos. 3,929,135, 4,151,240, 4,319,868, 4,324,426, 4,343,314 and 4,591,523. However, even non-woven or woven substrates can be apertured to improve their function of liquid acquisition.
Absorbent Core
According to the present invention the absorbent cores suitable for use herein may be selected from any of the absorbent cores or core system known in the art. As used herein the term absorbent core refers to any material or multiple material layers whose primary function is to absorb, store and distribute fluid. In FIG. 1 the absorbent structure is shown to comprise 3 layers 40 , 42 , and 44 .
The absorbent core of the present invention should have a high vapour permeability preferably also a high air permeability. The absorbent core preferably has a caliper or thickness of less than 12 mm, preferably less than 8 mm, more preferably less than 5 mm, most preferably from 4 mm to 2 mm.
According to the present invention, the absorbent core can include the following components: (a) an optional primary fluid distribution layer preferably together with a secondary optional fluid distribution layer; (b) a fluid storage layer; (c) an optional fibrous (“dusting”) layer underlying the storage layer; and (d) other optional components.
Primary/Secondary Fluid Distribution Layer
One optional component of the absorbent core according to the present invention, indicated as layer 40 in FIG. 1, is a primary fluid distribution layer and a secondary fluid distribution layer. The primary distribution layer typically underlies the topsheet and is in fluid communication therewith. The topsheet transfers the acquired fluid to this primary distribution layer for ultimate distribution to the storage layer. This transfer of fluid through the primary distribution layer occurs not only in the thickness, but also along the length and width directions of the absorbent product. The also optional but preferred secondary distribution layer typically underlies the primary distribution layer and is in fluid communication therewith. The purpose of this secondary distribution layer is to readily acquire fluid from the primary distribution layer and transfer it rapidly to the underlying storage layer. This helps the fluid capacity of the underlying storage layer to be fully utilised. The fluid distribution layers can be comprised of any material typical for such distribution layers.
b Fluid Storage Layer
Positioned in fluid communication with, and typically underlying the primary or secondary distribution layers, is a fluid storage layer ( 42 ). The fluid storage layer can comprise any usual absorbent material or combinations thereof. It preferably comprises absorbent gelling materials usually referred to as “hydrogel”, “superabsorbent”, hydrocolloid” materials in combination with suitable carriers, which are indicated as particles ( 43 ) in FIG. 1 .
The absorbent gelling materials are capable of absorbing large quantities of aqueous body fluids, and are further capable of retaining such absorbed fluids under moderate pressures. The absorbent gelling materials can be dispersed homogeneously or non-homogeneously in a suitable carrier. The suitable carriers, provided they are absorbent as such, can also be used alone.
Suitable absorbent gelling materials for use herein will most often comprise particles of a substantially water-insoluble, slightly cross-linked, partially neutralised, polymeric gelling material. This material forms a hydrogel upon contact with water Such polymer materials can be prepared from polymerizable, unsaturated, acid-containing monomers which are well known in the art.
Suitable carriers include materials which are conventionally utilised in absorbent structures such as natural, modified or synthetic fibers, particularly modified or non-modified cellulose fibers, in the form of fluff and/or tissues. Suitable carriers can be used together with the absorbent gelling material, however, they can also be used alone or in combinations. Most preferred are tissue or tissue laminates in the context of sanitary napkins and panty liners.
An embodiment of the absorbent structure made according to the present invention comprises a double layer tissue laminate. These layers can be joined to each other for example by adhesive or melting a polymeric powder binder (e.g. PE powder), by mechanical interlocking, or by hydrogen bridge bends. Absorbent gelling material or other optional material can be comprised between the layers.
Modified cellulose fibers such as the stiffened cellulose fibers can also be used. Synthetic fibers can also be used and include those made of cellulose acetate, polyvinyl fluoride, polyvinylidene chloride, acrylics (such as Orlon), polyvinyl acetate, non-soluble polyvinyl alcohol, polyethylene, polypropylene, polyamides (such as nylon), polyesters, bicomponent fibers, tricomponent fibers, mixtures thereof and the like. Preferably, the fiber surfaces are hydrophilic or are treated to be hydrophilic. The storage layer can also include filler materials, such as Perlite, diatomaceous earth, Vermiculite, etc., to improve liquid retention.
If the absorbent gelling material is dispersed non-homogeneously in a carrier, the storage layer can nevertheless be locally homogenous, i.e. have a distribution gradient in one or several directions within the dimensions of the storage layer. Non-homogeneous distribution can also refer to laminates of carriers enclosing absorbent gelling materials partially or fully.
An alternative are foam like or actual foam structures as liquid storage. There are open cell foams which absorb liquid and through chemical or surface interaction retain the liquid also under pressure. Such foams may be formed with a skin, thus providing on their wearer facing surface a smooth appearance which makes the use of a topsheet optional. Typical foams in this context are e. g. those disclosed in PCT publications WO 93/03699, WO 93/04092, WO 93/04113.
c Optional Fibrous (“Dusting”) Layer
An optional component for inclusion in the absorbent core according to the present invention is a fibrous layer adjacent to, and typically underlying the storage layer identified by reference numeral 44 in FIG. 1 . This underlying fibrous layer is typically referred to as a “dusting” layer since it provides a substrate on which to deposit absorbent gelling material in the storage layer during manufacture of the absorbent core. Indeed, in those instances where the absorbent gelling material is in the form of macro structures such as fibers, sheets or strips, this fibrous “dusting” layer need not be included. However, this “dusting” layer provides some additional fluid-handling capabilities such as rapid wicking of fluid along the length of the pad.
d Other Optional Components of the Absorbent Structure
The absorbent core according to the present invention can include other optional components normally present in absorbent webs. For example, a reinforcing scrim can be positioned within the respective layers, or between the respective layers, of the absorbent core. Such reinforcing scrims should be of such configuration as to not form interfacial barriers to fluid transfer. Given the structural integrity that usually occurs as a result of thermal bonding, reinforcing scrims are usually not required for thermally bonded absorbent structures.
Another component which can be included in the absorbent core according to the invention, and preferably is provided close to or as part of the primary or secondary fluid distribution layer or the fluid storage layer, are odor control agents such as zeolites, carbon black, silicates, EDTA or other chelates. Such agents are preferably provided in particulate form or as part of particles and can be provided together with the absorbent gelling material mentioned supra.
Backsheet
The absorbent article according to the present invention also comprises a breathable backsheet. The backsheet primarily has to prevent the extrudes absorbed and contained in the absorbent structure from wetting articles that contact the absorbent product such as underpants, pants, pyjamas, undergarments, and shirts or jockets, thereby acting as a barrier to fluid transport. In addition however, the breathable backsheet of the present invention permits the transfer of at least water vapour, preferably both water vapour and air through it and thus allows the circulation of air into and water vapour out of the article. The backsheet typically extends across the whole of the absorbent structure and can extend into and form part or all of sideflaps, side wrapping elements or wings, if present.
According to the present invention a dual or multiple layer breathable backsheet composite is used in the absorbent article. According to the present invention suitable breathable backsheets for use herein comprise at least a first and a second layer with said first layer being an air permeable layer. Preferred breathable backsheets for use herein are those having a high vapour exchange, most preferably both a high vapour and high air exchange.
The first layer is indicated as layer 50 in the drawings. It is positioned between the garment facing surface of the absorbent core and the wearer facing surface of the second layer which is indicated as layer 52 in FIG. 1 . It is oriented such that it retards or prevents liquid from passing from the absorbent core towards the outside while allowing free air flow through it.
According to the present invention the second layer ( 52 ) needs to provide at least water vapour permeability so as to support breathability of the article. It is not required but desirable that it also supports air permeability in order to further improve the comfort benefit from the breathability of the article. In this context suitable water vapour and air permeable layers include two-dimensional micro- or macro-apertured films, which can also be micro- or macroscopically expended films, formed apertured films and monolithic films, as well as nonwovens, or wovens.
Suitable 2 dimensional planar layers of the backsheet may be made of any material known in the art, but are preferably manufactured from commonly available polymeric materials. Suitable materials are for example Goretex (TM) or Sympatex (TM) type materials well known in the art for their application in so-called breathable clothing. Other suitable materials include XMP-1001 of Minnesota Mining and Manufacturing Company, St. Paul, Minn., USA and Exxaire XBF-101W, supplied by the Exxon Chemical Company. As used herein the term 2 dimensional planar layer refers to layers having a depth of less than 1 mm, preferably less than 0.5 mm, wherein the apertures do not protrude out of the plane of the layer. The apertured materials for use as a backsheet in the present invention may be produced using any of the methods known in the art such as described in EPO 293 482 and the references therein. In addition the dimensions of the apertures produced by this method may be increased by applying a force across the plane of the backsheet layer (i.e. stretching the layer).
Suitable apertured formed films include films which have discrete apertures which extend beyond the horizontal plane of the garment facing surface of the layer towards the core thereby forming protuberances. The protuberances have an orifice located at its terminating end. Preferably said protuberances are of a funnel shape, similar to those described in U.S. Pat. No. 3,929,135. The apertures located within the plane and the orifices located at the terminating end of protuberance themselves maybe circular or non circular provided the cross sectional dimension or area of the orifice at the termination of the protuberance is smaller than the cross sectional dimension or area of the aperture located within the garment facing surface of the layer. Preferably said apertured preformed films have a directional liquid transport and are positioned such that they support the prevention of liquid loss (leakage) through the backsheet. Suitable macroscopically expanded films for use herein include films as described for example in U.S. Pat. Nos. 4,637,819 and 4,591,523.
Suitable monolithic films include Hytrel™, available from DuPont Corporation, USA, and other such materials as described in Index 93 Congress, Session 7A “Adding value to Nonwovens”, J-C. Cardinal and Y. Trouilhet, DuPont de Nemours international S.A, Switzerland. Suitable non-wovens and/or wovens are any of those well known in the art. Non-wovens such as spunbonded, melt blown or carded which are thermobonded airlayed, drylayed or even wetlayed with or without binder can be used. Particularly preferred non-wovens are multilayer non-wovens such as a composite of fine melt blown fibers with more coarse spunbonded fibers with the meltblown fibers forming the wearer facing surface of the non-woven layer.
The first layer according to the present invention is preferably in direct contact with the absorbent core. It provides air and water vapour permeability by being apertured. Preferably this layer is made in accordance with the aforementioned U.S. Pat. No. 5,591,510 or PCT WO-97/03818, WO-97/03795. In particular, this layer comprises a polymeric film indicated in FIG. 1 as first layer ( 50 ), having capillaries ( 54 ). The capillaries extend away from the wearer facing surface of film ( 50 ) at an angle which is less then 90 degrees. In FIGS. 2 through 7 alternative embodiments of such capillaries are shown. Preferably the capillaries are evenly distributed across the entire surface of the layer, and are all identical. However, layers having only certain regions of the surface provided with apertures, for example only an area outside the region aligned with the central loading zone of the absorbent core, maybe provided with capillaries according to the present invention.
Methods for making such three-dimensional polymeric films with capillary apertures are identical or similar to those found in the apertured film topsheet references, the apertured formed film references and the micro-/macroscopically expended film references cited above. Typically a polymeric film such as a polyethylene (LDPE, LLDPE, MDPE, HDPE or laminates thereof) is heated close to its melting point and exposed through a forming screen to a suction force which pulls those areas exposed to the force into the forming apertures which are shaped such that the film is formed into that shape and, when the suction force is high enough, the film breaks at its end thereby forming an aperture through the film.
Various forms, shapes, sizes and configurations of the capillaries are possible and will be discussed in reference to FIGS. 2 through 7 in the following. The apertures ( 53 ) form capillaries ( 54 ) which have side walls ( 56 ). The capillaries extend away from the wearer facing surface of the film ( 55 ) for a length which typically should be at least in the order of magnitude of the largest diameter of the aperture while this distance can reach up to several times the largest aperture diameter. The capillaries have a first opening ( 57 ) in the plane of the garment facing surface of the film ( 55 ) and a second opening ( 58 ) which is the opening formed when the suction force (such as a vacuum) in the above mentioned process creates the aperture. Naturally the edge of the second opening ( 58 ) may be rugged or uneven, comprising loose elements extending from the edge of the opening. However, it is preferred that the opening be as smooth as possible so as not to create a liquid transport entanglement between the extending elements at the end of the second opening ( 58 ) of the capillary ( 54 ) with the absorbent core ( 44 ) in the absorbent article (in contrast this may be desirable for apertured film topsheets where such loose elements provide the function of sucker feet).
As shown in FIG. 4 the first opening has a center point ( 157 ) and the second opening also has a center point ( 158 ). These center points for non-circular openings are the area center points of the respective opening area. When connecting the center point ( 157 ) of the first opening ( 57 ) with the center point ( 158 ) of the second opening ( 58 ) a center axis ( 60 ) is defined. This center axis ( 60 ) forms an angle ( 59 ) with the plain of the film which is the same plain as the garment facing surface of the film ( 55 ). This angle should be preferably in the range between 85 and 20 degrees, more preferably between 65 degrees and 25 degrees, and most preferably between 55 and 30 degrees.
It is of course possible to allow the capillaries to take the shape of a funnel such that the second opening ( 58 ) is (substantially) smaller than the first opening ( 57 ) when considering the opening size in a plain perpendicular to the center axis ( 60 ). Such an embodiment is shown in FIG. 3 and FIG. 2 . In FIG. 2 it is also shown that the wall ( 56 ) of the capillary may not end in the second opening ( 58 ) such that the opening forms a surface perpendicular to the center axis ( 60 ) but such that the wall on the portion of the capillary further apart from the wearer facing surface of the film ( 55 ) extends over the opening to further aid the film in reducing the probability of liquid migrating through the capillaries from the absorbent core on the wearer facing side of the film ( 55 ) to the garment facing side of the film (and cause leakage).
In FIG. 5 another embodiment of the capillaries useful for the present invention is shown which is curved along its length towards the wearer facing surface of the film ( 55 ). This has a similar effect as the extension of the wall ( 56 ) as shown in FIG. 2 .
In FIG. 6 another preferred embodiment of a capillary according to the present invention is shown which has a first portion ( 257 ) and a second portion ( 258 ). The first portion ( 257 ) of the capillary is different in direction than the second portion ( 258 ) of the capillary ( 54 ). This difference can also be in shape, size, and form of the portions of the capillary in order to achieve the desired level of breathability while preventing liquid passage through the film in a direction from the wearer facing side towards the garment facing side. Such an example is shown in FIG. 7 .
Without wishing to be bound by theory it is believed that the capillaries according to the present invention in the first layer of the breathable backsheet allow air and water vapour permeability which is not hindered by them being slanted at an angle or by the shape as indicated above. At the same time the slanting and shaping according to the present invention will allow the capillaries to close under pressure excerpted from the wearer facing side on them such that liquid transport through the capillaries towards the outside of the article becomes nearly impossible. Hence these three-dimensional formed film layers are highly preferable in the context of breathable absorbent articles and in particular so if an additional second outer layer is provided.
Absorbent Article Construction
A further aspect of the present invention relates to the joining of the topsheet, backsheet and absorbent core elements to provide the absorbent article. According to the present invention at least two, preferably all of the elements of the article are joined.
Each of said elements comprising at least one layer has a wearer facing surface and a garment facing surface. Typically, adjacent garment facing surfaces form a common interface with the wearer facing surface of an adjacent element or layer. The elements or layers are joined together across this common interface. In this manner the topsheet is joined to the absorbent core, and the core is joined to the backsheet. Furthermore, each of said topsheet, backsheet and core elements may comprise more than one layer and these layers may also be similarly joined. In addition the topsheet may be directly or indirectly joined to the backsheet at the periphery of the absorbent article to contain the absorbent core.
The elements and layers thereof may be joined by any means known in the art for affixing two adjacent layers of material, such that the layers are directly attached to one another or directly attached to one another via the joining means. Suitable joining means include adhesive, fusion bonding, ultra sonic bonding, stitching, heat (e.g. thermobonding by welding fibers at intersections or melting a polymer to attach fibers or films to each other), embossing, crimping, pressure bonds, dynamic mechanical bonds or combinations thereof. According to an embodiment of the present invention the preferred means of joining is adhesive. Suitable adhesives include non pressure sensitive and cold adhesives. The adhesive may be applied by any means known in the art such as spiral application, slot coating, spraying, spiral spraying, curtain coating, contact coating and printing, provided that the adhesive does not substantially affect the breathability and other functions of the elements of the article.
One means of achieving this is to use particular adhesive application methods such as open adhesive application techniques, whereby areas of the common interface are adhesive free, whilst retaining the required level of attachment/joining of the two adjacent layers or elements. In particular spiral spraying is preferred.
In a preferred embodiment of the present invention wherein the absorbent article finds utility as a sanitary napkin or panty liner, the absorbent article is also provided with a panty fastening means which provides means to attach the article to an undergarment. For example the panty fastening means may comprise a mechanical fastener such as hook and loop fasteners such as marketed under the tradename VELCRO, snaps or holders. Alternatively, the article is fastened to the undergarment by means of panty fastening adhesive on the backsheet. The panty fastening adhesive provides a means for securing the article to the panty and preferably a means for securing the article when soiled, to the fold and wrap package for convenient disposal. Typically, at least a portion of the garment facing surface of the backsheet is coated with adhesive to form the panty fastening adhesive. Any adhesive or glue used in the art for such purposes can be used for the panty fastening adhesive herein. Pressure sensitive adhesives are most preferred. Suitable adhesives include Century A-305-IV manufactured by the Century Adhesives Corporation of Columbus, Ohio, and Instant LOK 34-2823 manufactured by the National Starch and Chemical Company of Bridgewater, New Jersey, 3 Sigma 3153 manufactured by 3 Sigma and Fuller H-2238ZP manufactured by the H.B. Fuller Co.
In order to reduce the adverse effect on breathablility of the backsheet (and thus of the article as a whole), the adhesive is preferably applied such that at least 60%, preferably from at least 80%, most preferably at least 90% of the surface of the backsheet is adhesive free. The required adhesiveness can still be achieved even when using reduced surface coverage by using a particular distribution such as thinner strips, discontinuous strips of adhesive, intermittant dots, random patterns or spirals.
The panty fastening adhesive is typically covered with a removable release paper or film in order to prevent the adhesive from drying out or adhering to another surface other than the panty prior to use. Any commercially available release paper or film may be used. Suitable examples include BL 30MG-A SILOX EI/O and BL 30 MG-A SILOX 4 P/O available from Akrosil Corporation.
According to the present invention the absorbent article can be used beneficially in the context of sanitary napkins, panty liners, incontinence articles, sweatpads and diapers. However, sanitary napkins are particularly susceptible to the present invention. The disposable article may thus also have all those features and parts which are typical for products in the context of their intended use. | A breathable disposable absorbent articles of layered construction, each layer having a garment facing surface, and a wearer facing surface. The breathable disposable absorbent article comprises at least a first backsheet layer and a second backsheet layer. At least one of the breathable layers of the backsheet comprises a resilient, three-dimensional web, which consists of a liquid impervious polymeric film having apertures. The apertures form capillaries, which are not perpendicular to the plane of the film but are disposed at an angle of less than 90° measured from the plane of the film. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a division of U.S. application Ser. No. 07/205,004 filed Jun. 3, 1988, now U.S. Pat. No. 4,849,230, issued Jul. 18, 1989, which in turn is a continuation of U.S. application Ser. No. 06/880,151, filed Jun. 30, 1986, abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a breadmaking method for producing crisp, long term preservation, small loaves or buns on an industrial scale.
2. Description of the Prior Art
There exists a demand for a bread which can retain enhanced fragrant and crisp properties over time.
Current techniques for making bread from a paste or dough composed of water, flour, and yeast, may be reduced to the following cycle: dough is first made as homogeneous as possible through successive mechanical processing, allowed to leaven, cut into pieces providing a stock or blank which is fashioned into desired forms, after which, following as a rule further leavening, the bread forms are baked.
The structure of bread so made is generally characterized by a dense outer crust and a fine cellular underlayer and a soft elastic inner crumb of a more or less pronounced character which is unevenly distributed.
However, it is a well known fact that traditional bread undergoes, after a more or less short time period, a series of structural and organoleptic changes leading to its first becoming stale and then dry.
Bread crumb in particular is liable to undergo such structural alterations and progressively lose its elastic character to become coarse and abrasive, and therefore, unpalatable.
Other prior techniques for processing flour-based pastes or doughs yield bread-substitutive products, mainly crackers and bread sticks, which notoriously preserve well for a relatively long time.
It should be noted, however, that such substitutes have none of the fragrant and appetizing qualities of fresh bread.
Thus, such products fail to meet the above-mentioned demand.
The problem underlying this invention is, therefore, that of providing a novel breadmaking method whereby it becomes possible to produce on an industrial scale small loaves or buns which can retain all the characteristics of fresh bread over time, and specifically its flavor, fragrance, and crispness.
SUMMARY OF INVENTION
Broadly a solution for this problem is one of dealing with breadmaking dough, directly downstream of its preparation, to modify its chemical and physical state through violent mechanical treatments whereby baking will yield a loaf or bun the whole structure whereof is similar to the crust of traditional bread, being finely cellular and evenly distributed.
This solution is realized by a breadmaking method for producing crisp long term preservation small loaves or buns, which comprises the following process steps:
preparation of a breadmaking dough from high gluten content flour (proteins in excess of 12%) and water in amount lower than 40 bulk % based on flour bulk, and with the addition of yeast,
rolling said dough until a breadmaking dough having visco-elastic characteristics is obtained,
feeding a metered amount of said breadmaking dough into a mold cavity, the volume of said amount being substantially equal to the volume of said mold cavity,
compressing said amount of breadmaking dough by direct action thereon until it fills by viscoelastic flowing said mold cavity substantially throughout, yielding a sheet-like compressed flat loaf blank,
releasing the pressure on the flat sheet-like blank and shaking it out of the mold cavity,
imparting said flat sheet-like blank with the final loaf shape,
leavening the product from the preceding step, and
baking the leavened product and drying it down to a lower moisture content of less than 10%.
While this method runs counter to traditional breadmaking techniques, which all observe a common criterion of avoiding, as far as possible, any violent mechanical handling of the breadmaking dough downstream of the rolling step in order to minimize disturbance of the leavening process, it has been found in actual practice that the resulting product was stable over time from both a chemical and physical standpoint and an organoleptic standpoint, and accordingly, adapted for long term storage without alteration of its initial properties of fragrance and crispness.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of an industrial breakmaking system for producing long term preservation crisp loaves or buns;
FIG. 2 is a top plan view of a portion of the breadmaking apparatus of FIG. 1;
FIG. 3 is a longitudinal section view taken along line 3--3 of FIG. 2;
FIG. 4 is a fragmentary perspective view of a pressure molding station for compressed flat bun blanks and comprising a portion of the breadmaking apparatus of FIG. 1;
FIG. 5 is a section view taken along line 5--5 of FIG. 4;
FIG. 6 is a diagrammatic elevational view, partly in section showing a loaf or bun forming station of the breadmaking apparatus of FIG. 1; and
FIG. 7 is a detailed perspective view of one portion of the bun forming station of FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An illustrative and not limiting example will be described herein below of an application of the inventive method.
EXAMPLE 1
To prepare a breadmaking dough, the following ingredients were used:
100 kg flour having a protein content of about 13% by weight, which when analyzed by the Chopin Method, gave the following index values:
W=260, P/L=0.5;
35 kg water;
3 kg breadmaking yeast.
To the mixture were added 5 kg olive oil, sodium chloride, and malt in conventional dosages.
The kneading operation was conducted in two stages separated by a rest period of about 6 hours (two-stage dough).
The resulting dough was particularly consistent, and was then subjected to a series of successive rolling steps on a rolling machine until it yielded a homogeneous web of breadmaking dough strip (of the so-called "hard dough" type) exhibiting viscoelastic characteristerics and being 25 mm thick.
The breadmaking dough thus obtained has a specific density of 1.05 kg/dm 3 .
The breadmaking dough strip was then fed into the nip of two parallel rollers driven rotatively at a peripheral velocity of 0.19 m/sec and held in tangential contact along a common generating line.
One of those rollers had plural molding cavities of triangular shape formed on its outer sleeve which have an average depth of 4 mm, the other roller having a smooth outer sleeve.
Dough would only be passed between the rollers where an empty mold is present directly upstream of the contact generating line therebetween.
It has been found that in going through the roller nip, the dough underwent a high and rapid compression causing it to flow viscoelastically to almost completely fill a respective molding cavity.
Downstream of the rollers, a compressed flat blank was obtained that was made easier to shake out of the mold cavity by the elastic recovery tendency of breadmaking dough.
The flat blank was then rolled up and allowed to leaven to a 45% swell by volume.
The leavened product was then baked at a temperature of about 250 to 270 degrees centigrade to yield a sample small loaf or bun of a rich brown color which was both consistent and crisp.
The sample loaf or bun was then dried to a moisture content of 5%, and on breaking, it showed a fine cellular and homogeneously dispersed structure.
20 days later, the sample loaves or buns so obtained showed no significant changes in consistency, flavor, fragrance, and crispness.
In the course of further tests, it was found that best results are to be obtained by using high gluten content flours (with a protein content of no less than 12%).
By way of non-limitative example, a system will be now described for producing crisp small loaves or buns on an industrial scale, which is particularly suitable to implement the inventive method.
A system for producing crisp small loaves or buns on an industrial scale comprises a kneading machine, a rolling machine, a forming machine, a leavening chamber, a baking oven, and a drier, in that order.
In the accompanying drawings, only the forming machine, comprehensively designated 1, is shown, the remaining machines being omitted because quite conventional.
The forming machine 1 comprises, in turn, a molding station 2, a wetting station 3, and a final forming station 4, in that order.
A breadmaking dough being processed will move through the above-mentioned machines in the order indicated.
The molding station 2 comprises a feeder assembly 5 composed of a frame 5c which carries rotatably a plurality of power driven roller roll pairs 5a, 5b with parallel axes.
A gap is defined between each roller pair 5a, 5b wherethrough a breadmaking dough 6 is made to pass.
The dough 6 reaches the feeder assembly 5 in the form of plural breadmaking dough strips (eight webs in the example shown) and goes sequentially through the nips of all the roller pairs 5a, 5b.
The size of said gap, for adjoining roller pairs, decreases in the direction of advance of the dough 6 as indicated by the arrow A.
Downstream of the feeder assembly 5, there are a pair of rollers, respectively a die roller 7 and a backup roller 8, lying parallel to each other and to the rolling rollers 5a, 5b and being driven counter-rotatingly by motors, not shown.
The rollers 7 and 8 are journalled on a pair of shoulders 13 of a framework 10 by means of respective seals 11 and 12.
The seals 12 are supported slidingly within respective seats 13a formed in the shoulders 13.
Respective screw adjusters or registers comprising a screw portion 14 and a nut portion 14a are mounted on each shoulder 13 and connected to their corresponding seal 12 to adjust its position relatively to the seal 11, and change, if desired, the distance between rollers 7 and 8.
The screw adjusters or registers 14, 14a form a means of positioning the roller 8 relatively to the roller 7; such means are essentially provided to position said rollers in mutual contact relationship along a common generating line B.
The roller 7 has a plurality of molding cavities 15, hereinafter referred to as the "molds", which are distributed regularly across its generating line segments. The number of the molds 15 which are aligned along any generating line of the roller 7 is equal to the number of the strips of dough 6 oncoming to the feeder assembly 5.
The molds 15 have substantially triangular shape with rounded off apexes, and have their bottoms partially coated with an adhesion-preventing material, such as an epoxy resin.
The roller 8 has a smooth outer sleeve and doctoring members 16 are active thereon, one for each cylindrical segment of molds 15. The doctoring members 16 are carried on a shaft 17 which extends between the shoulders 13 and have a blend 16a set to the sleeve of the roller 8 directly downstream of the generating line B.
The molding station 2 further comprises a carpet conveyor 20 trained in a closed loop around respective rollers 21, and having one end held close to the roller 7 by a nose 22. The carpet 20 has a working conveying surface 23.
A levelling roller 24 is supported idly between the shoulders 13 downstream of the rollers 7, 8 and above the working surface 23; the roller 24 is rubber foam lined.
The wetting station 3 and final forming 4 stations are both carried on a frame 28 extending mainly in a longitudinal stringers or bars 28a and 28b which are provided, in turn, with legs 29. To the legs 29, at a region underlying the longitudinal stringers or bars 28a, 28b, there is also connected a pan 27 for collecting any scrap dough.
The wetting station 3 comprises, downstream of the carpet 20, a number of mesh conveyors 31 equal in number to molds 15 aligned along any generating line of the roller 7, and moving in the same direction as the carpet 20 and facing out in the direction of the arrow A.
The product travelling on the mesh conveyors 31 is subjected to water spray jets which are delivered at a preset rate from spray members indicated diagrammatically at 21a.
The final forming station 4 comprises a carpet conveyor 30 having a working area 32 on the same plane as the mesh conveyors 31.
The carpet 30 is stretched between rollers 30a and 30b journalled on the longitudinal stringers or bars 28a and 28b.
Between the mesh 31 and carpet 30 conveyors there intervene a pair of rollers 33, in parallel stacked relationship, which are powered and laid across the direction of advance of the product being processed (arrow A).
A gap is defined between the rollers 33 which has a set width to let said product being processed therethrough.
The rollers 33 are also journalled on the longitudinal stringers or bars 28a and 28b.
Directly downstream of the rollers 33, a portion of the working area 32 of the carpet conveyor 30 is acted upon by roll-up device 35.
The device 35 comprises a frame 36 extending across the direction (A) of advance of the product being processed and being fastened to the longitudinal stringers or bars 28a, 28b at a region overlying the carpet 30.
A plurality of clamps 37 extending vertically to the working area 32 of the carpet 30 are hooked on the frame 36 which are provided in the proximity of the working area with respective pads 37a of felt or the like comparatively soft material having a frictional coefficient.
The pads 37 are spring mounted to their respective clamps 37.
The station 4 further comprises a folding device 40 having a slide 41 movable along runways 42, in turn made fast with the longitudinal stringers or bars 28a, 28b.
The slide 41 has a crosspiece 43 which extends bridge-fashion over the working area of the carpet conveyor 30. Mounted on the crosspiece 43 are a plurality of fluid-operated cylinders 44 each having a piston rod 45 which extends in a perpendicular direction to the working area 32 of the carpet 30 and a corresponding plurality of C-brackets 46 located between the crosspiece 43 and said working area 32. The brackets 46 have a bore 47 wherethrough the corresponding piston rod 45 is guided. Said brackets 46 are effective to prevent, with the piston rod 45 raised, the product being processed from sticking to the piston rod.
The slide 41 is reciprocated in a parallel direction to the arrow A by a connecting rod-crank lever type of linkage generally indicated at 50.
The piston rods 45 are drawn up, by respective cylinders 44 forming drive means therefor, to a raised position toward the crosspiece 43 each time that the movement of the slide 41 takes place in the opposite direction to the advancing product being processed, and are extended out, with their free ends brought close to the carpet 30 on said movement taking place in the same direction as the arrow A.
The piston rods 45 perform, therefore, with respect to the frame 28, a rectangular cycle movement in a perpendicular plane to the working area of the carpet 30 in parallel with the arrow A.
Of that cyclic movement, the travel path of the rods 45 down toward the carpet 30 will be referred to as the "active path".
The folding device 40 further comprises a corresponding plurality of pairs of juxtaposed templates 51, each pair delimiting a passageway located along the active path of the corresponding piston rod 45.
The template pairs 51 are mounted stationary on the frame 28 and have confronting surfaces 52 which are curved and concave in a symmetrical arrangement with respect to the plane wherein the corresponding piston rod moves.
Each template pair 51 overlies, over at least some distance, a corresponding conveyor belt 54 provided for transporting the product to the leavening chamber and then to the baking over.
The production steps for crisp small loaves or buns made with the inventive method will be now described in connection with the system just described.
The ingredients are kneaded in two stages, that is two distinct kneading sub-steps separated by a rest period, using high gluten content (protein content of about 13-14%) flour, water in the amount of about 35-37% bulk based on the dry flour, yeast, olive oil, malt, and salt bulk.
The resulting dough is subjected to sequential rolling passes until a homogeneous breakmaking dough sheet is obtained which has visco-elastic characteristics.
The dough sheet is then fed into a rolling machine where roller pairs will roll it into sheets of decreasing thickness.
The last roller pair in the rolling machine will split the rolled dough into plural strips 6, as shown in the drawings.
The breadmaking dough strips are then taken to the feeder assembly 5, wherein they undergo additional thickness reduction by rollers 5a, 5b.
For each dough strip there corresponds, as mentioned previously, one cylindrical segment having molds 15 in the die roller 7.
The speed of the roller pairs 5a, 5b is constant over time, and accordingly the amount of the dough which is being fed into the nip of the rollers 7 and 8 is also constant, while drawing of dough into any mold 15 of the roller 7 would be cyclic and dependent on an empty mold moving past the feeder 5.
Thus, each dough strip 6 upstream of the rollers 7 and 8 will be subjected to an intermittent forward movement at the same rate as the respective molds 15 moving past.
During the wait for fresh empty mold 15, the dough 6 undergoes a consequent slight build-up upstream of the rollers 7, 8.
When a mold 15 is present directly upstream of the generating line B of contact of the rollers 7, 8, the dough build-up will be drawn into it in a volume approximately equal to the volume of the mold 15 cavity.
The dough is forced to flow visco-elastically to almost completely fill the cavity of the mold 15 while contributing, on account of its consistency and toughness, a significant elastic reaction force, to deliver, downstream of the generating line B and for each mold 15, a compressed flat blank 60.
By way of illustration, it has been found that rollers 7, 8 820 mm long and having an outside diameter of 270 mm, with eight mold cavities 15 aligned on one generating line, are subjected in operation to a load in the region of 15 to 30 tons.
The blanks 60 undergo, directly downstream of the generating line B, a slight amount of elastic recovery which results in their becoming detached from the respective molds.
Any blanks 60 sticking to the backup roller 8 would be removed therefrom by doctoring means 16.
The blanks 60 are then load onto the carpet conveyor 20 and rolled out thereover by the levelling roller 24.
They are wetted in going through the station 3 in a manner already described previously, and subjected to further rolling through the nip of the rollers 33.
Downstream of the rollers 33, each blank will have a leading portion (in the direction of the arrow A) which curls slightly upward to invite subsequent rolling up at the device 35.
In moving underneath the flat pads 37a, the blanks 60 entrained by the carpet 30 are rolled up into a substantially cylindrical configuration indicated at 61 in the drawings.
The cylindrical blanks 61 are taken forward by the carpet 30 toward the templates 51 of the folding device 40.
Directly upstream of the templates 51, each blank 61 will be reached by the piston rod 45 of its corresponding fluid-operated cylinder 44, taken by the slide 41 in the opposite direction to the advancing direction of the carpet 30. Each piston rod 45 is lowered onto the carpet 30 directly upstream of a corresponding blank 61 and follows it in its path of travel up to the templates 51, to force it through the gap between the confronting surface 52 of the latter.
Thus, the blanks 61 will be bent into a crescent-like shape as indicated at 62 in the drawing.
From the templates 51 they are then discharge onto the belt conveyors 53, and whence onto the carpet conveyor 54, to be taken to a leavening chamber where they are allowed to stand at a temperature of 36° C. for about one hour, their volume increasing by 45%.
The leavened blanks are then baked at a temperature in the 250° to 270° C. range.
On leaving the oven, they are dried until their moisture content drops to about 5%, and then packaged into bags, boxes, or other appropriate commercial packaging containers. | An apparatus for producing crisp, long term preservation, small loaves on an industrial scale including a forming machine having a feeder assembly, a molding station and a forming station laid sequentially to each other. The feeder assembly includes a plurality of parallel, sequentially-laid driven roll pairs, a gap between corresponding roll pairs decreasing in width from the most upstream roll pair to the most downstream roll pair. The molding station includes first and second counter rotating driven rolls, the first roll having a plurality of mold cavities uniformly distributed across its skirt, and the second roll having a smooth surface skirt, the rolls being mounted in pressure contact with each other. The forming station includes a folder device. | 0 |
The present invention relates to a mechanism for implementing an efficient microkernel architecture for constructing graphical user interfaces capable of scalable embedded, desktop and network distributed applications. The invention disclosed broadly relates to graphical user interfaces (GUI's) and particularly relates to the software architectures used to implement them.
BACKGROUND OF THE INVENTION
Much like operating systems (OS's) of the 1980's and earlier, which used a monolithic kernel architecture, windowing systems or graphical user interfaces (GUI's) of the 1980's and 1990's have also been implemented with a monolithic kernel. Graphics drivers, input device drivers, and the other functionality of these GUI's all exist within the common address space of the GUI kernel.
In the 1990's, many OS vendors started experimenting with microkernel operating systems, recognizing that this architecture provided the best approach to delivering the new functionality demanded by their customers. For the same reasons that a microkernel architecture has been adopted in the OS community, the GUI community needs to also adopt a microkernel approach.
Description of a Microkernel OS
The basic idea behind a microkernel architecture is to abstract out the core services or "primitives" from which the higher level functionality of the environment can be constructed. The resulting microkernel can be relatively simple. The "art" of microkernel design is in deciding which core services are essential to have within the kernel, and which should be implemented external to the microkernel. Engineering the architecture requires a constant analysis of conflicting trade-offs as pursuing certain design ideals will adversely impact other goals of the system (eg. performance, flexibility, etc).
Historically, OS functionality was implemented within a monolithic kernel to minimize the number of times time-consuming address space transitions were executed in the process of servicing an application request. Rather than having all of the functionality of the OS implemented in a single monolithic kernel that application processes call into, a microkernel OS is implemented as a tiny kernel that does only inter-process communication (IPC) and process scheduling. External processes then use these core services to implement the remainder of the OS functionally. The removal of complexity from the kernel allows a more efficient IPC implementation, which reduces the performance penalty incurred (from communicating with external service-providing processes) to the point that it becomes comparable in performance to the monolithic functional equivalent.
Splitting the monolithic kernel into separate processes also enables the easier implementation of new functionality. For example, by making the microkernel IPC network transparent, the service providing processes can be run on any node on a network, yet still be locally accessible to application processes. This serves to make all resources available to all processes, whether local or network remote. Monolithic kernels have a very difficult time attempting this functionality with efficiency because the "single component kernel" cannot be easily split across processor boundaries.
Problems With the Current State of the Art
Network distributed computing environments and embedded GUI applications have become common due to increasing integration and decreasing hardware costs. Customer demands for even greater flexibility continue to increase. For example, the growing popularity of mobile hand-held computing devices or Personal Digital Assistants (PDA's). For reasons of cost sensitivity, battery life and physical size restrictions, the hardware resources of PDA's are significantly more limited than those of conventional desktop systems. As a result, there is a need for PDA software to make efficient use of these limited resources, which presents a number of challenges to developers. This is one example where many of the GUI development obstacles are satisfied by the inherent design flexibility of a microkernel architecture.
Since a desktop system can run a more complete version of the same software environment that will run on an embedded application platform, the desktop PC also becomes a natural development platform for the embedded application, rather than incurring the inconvenience of a cross-development environment. Being able to use visual and textual tools to directly create, compile and debug the PDA or embedded applications on a workstation or PC minimizes the development effort and reduces the "time to market".
Rapidly evolving hardware capabilities also requires that the software environment be able to rapidly accommodate modifications to support that hardware, both as variations of common hardware devices, and as entirely new types of hardware, requiring more substantial changes to the underlying software environment's capabilities.
Existing GUI's cannot be scaled small enough to fit within the resource constraints of low-end PDA's and embedded systems. As a result, a need has been created for a GUI adaptable to both low-end, resource-constrained systems, and large-scale, network distributed systems. Existing monolithic GUI designs cannot simultaneously accommodate these requirements. As a result, vendors are forced to create multiple, completely distinct, GUI products to attempt to address the various markets, while their current monolithic product offerings still fail to address the distributed networking needs. This results in duplication of development and maintenance efforts relating to the GUI, as well as to required drivers, and raises compatibility concerns.
It is therefore desirable to create a microkernel GUI with many of the same attributes as a microkernel OS, using the approach of a tiny microkernel that implements only a few primitives. With such an approach, a team of external cooperating processes invoking those microkernel services could be used to construct a windowing system. An important aspect of such a design is to decide what those primitives should be, such that a high-performance, high-functionality, high-flexibility GUI can be built from the GUI microkernel. Inappropriate design decisions in the microkernel could result in a poor-performing system, due to additional overhead incurred from the IPC between the cooperating processes. A microkernel design would have to recover this IPC performance overhead through architectural and design performance advantages accrued from other aspects of the GUI, such as greater concurrency.
A microkernel GUI would have a number of advantages over monolithic kernel GUI's, advantages which equate directly to both better functionality and unique capabilities.
a) Scalability: Simply by including or excluding service-providing processes associated with the microkernel GUI, the functionality (and resource requirements) of the GUI could be scaled to address different application needs ranging from small embedded systems to high-end, high-functionality systems. The vendor would only have to create and maintain a single GUI product, rather than a family of products for different environments.
b) Extensibility: As new functionality requirements arise (eg. handwriting recognition, voice recognition, etc.) a microkernel GUI can easily be extended by adding specific service-providing processes. Moreover, these functionality enhancements can be readily accomplished by application developers, rather than requiring (or waiting for) the GUI vendor to implement them. To accommodate additions with a monolithic kernel GUI, the entire GUI would have to be replaced with a new, enhanced version by the GUI vendor. If a developer needs a unique extension, the microkernel approach lets the developer develop those extensions himself, rather than be bound by the original implementation limits.
c) Address protection: With the components of the GUI running in separate, MMU-protected (memory management unit) address spaces, coding errors in one section of the GUI would be contained, and could not cause problems in other sections. Latent bugs in the code would also be likely to "trip" the MMU protection, leading to the early detection of programming errors, rather than have them discovered by end-users of the application. In general, this allows the extensions developed (either by the software vendor or an application developer) to be easily and reliably integrated into the GUI, and results in a more robust GUI.
d) Concurrency: With the GUI running as several concurrent processes, it could demonstrate greater concurrency in it's processing than a single-threaded monolithic kernel GUI. Multiple components of the GUI, since they're implemented as separate processes, can execute concurrently, especially if they're running on different nodes on the network. Although a monolithic GUI could use multiple threads of execution within the monolithic GUI kernel, the complexities of semaphores and mutexes would make it difficult to implement the GUI robustly with the same degree of concurrency. The threaded monolithic kernel also cannot make use of multiple processors except in an SMP (symmetric multiprocessor). The microkernel approach can make use of processors on other network nodes.
e) Network Distribution: If the underlying IPC used by the microkernel GUI was network transparent, all of the components of the GUI could be run on different processors in a distributed system. This would enable a class of distributed GUI capabilities not available using a monolithic GUI. For example, applications could be dragged from one computer's screen onto the screen of a hand-held device connected using a wireless LAN link. This is not possible with a monolithic GUI because the monolithic GUI kernel cannot be broken into separate pieces, each running on a different node on the network.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a system for managing the interaction of programs, comprising means for storing a set of predetermined characteristics respecting each program to be managed, each set of characteristics including an input signal type characteristic indicative of the identity of the type of inputs signals to which the program associated with the set of characteristics is responsive and a signal modification characteristic indicative of whether a type of input signal is to be modified by the associated program; means responsive to input signals having predetermined properties emitted from one of the programs for interrogating each set of predetermined characteristics in a predetermined sequence, determining whether the associated program is responsive to a current input signal, determining whether the properties of the current input signal are to be modified and, if so, modifying the properties of the input signal; and means for emitting an output signal to the programs determined to be responsive to the input signal.
Further features of this invention will be apparent from the following description and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings wherein:
FIG. 1 is a perspective view of the present invention's Event Space illustrating Regions as visualized by a user;
FIG. 2 is a front view of the present invention's Event Space illustrating overlapping Regions and an Event as modified by intersections with Opaque Regions A, B and C;
FIG. 3 is a front view of the Event Space illustrating the cartesian layout of the present invention's coordinate space and its dimensions;
FIG. 4 is a perspective view of the present invention's Event Space illustrating the root Region as viewed by a user;
FIG. 5 is a perspective view of the present invention's Event Space illustrating device Regions and application program Regions;
FIG. 6 is a perspective view of the present invention's Event Space illustrating the emission of a draw Event from an application program Region;
FIG. 7 is a perspective view of the present invention's Event Space illustrating the use of multiple graphics drivers;
FIG. 8 is a perspective view of the present invention's Event Space illustrating the window Region in relation to the application program and root Regions;
FIG. 9 is a perspective view of the present invention's Event Space illustrating the window and focus Regions in relation to the root Region;
FIG. 10 is a perspective view of the present invention's Event Space illustrating the workspace Region in relation to the root and window Regions;
FIG. 11 is a perspective view of the present invention's Event Space illustrating the backdrop Region in relation to the workspace and window Regions;
FIG. 12 is a front view of the present invention's Event Space illustrating the cartesian layout of the coordinate space and the positioning of a graphics driver Region;
FIG. 13 is a front view of the present invention's Event Space illustrating the relationship between a Region's origin and its initial rectangle coordinates;
FIG. 14 is a front view of the present invention s Event Space illustrating the relationship between a Region's origin and its initial rectangle coordinates for Regions that fill the entire coordinate space;
FIG. 15 is a front view of the present invention's Event Space illustrating how a Child Region's origin can differ from its Parent Region's origin;
FIG. 16 is a front view of the present invention's Event Space illustrating a Child Region overlapping its Parent's Region;
FIG. 17 is a front view of the present invention's Event Space illustrating a portion of a Child Region that does not overlap its Parent Region;
FIG. 18 is a hierarchy chart illustrating the Parent-Child relationship giving rise to a Region hierarchy;
FIG. 19 is a side view of the present invention's Event Space illustrating the relative placement of Parent and Child Regions;
FIG. 20 is a side view of the present invention's Event Space illustrating the relative placement of Brother Regions;
FIG. 21 is a side view of the present invention's Event Space illustrating the relative placement of a Parent Region and a Child Region which has not been flagged to over-ride default placement;
FIG. 22 is a side view of the present invention's Brent Space illustrating the relative placement of Brother Regions where no Brother Region has been flagged to over-ride default placement;
FIG. 23 is side view of the present invention's Event Space illustrating the relative placement of a Parent Region and a Child Region that has been flagged to over-ride default placement;
FIG. 24 is a side view of the present invention's Event Space illustrating the relative placement of two Brother Regions where one Brother Region has been flagged to over-ride default placement;
FIG. 25 is a side view of the present invention's Event Space illustrating the relative placement of three Brother Regions where one Brother Region has been flagged to over-ride default placement;
FIG. 26 is a flow chart illustrating the Main Processing loop of the present invention;
FIG. 27 is a flow chart illustrating the Region processing loop of the present invention;
FIG. 28 is a flow chart illustrating the Open Region processing loop of the present invention;
FIG. 29 is a flow chart illustrating the Close Region processing loop of the present invention;
FIG. 30 is a flow chart illustrating the Change Region processing loop of the present invention;
FIG. 31A is a flow chart illustrating the Event Processing loop of the present invention;
FIG. 31B is a continuation of the flow chart illustrating the Event Processing loop of ale present invention;
FIG. 31C is a continuation of the flow chart illustrating the Event Processing Loop of the present invention.
Similar references have been used in different drawings to indicate similar components.
DESCRIPTION OF PREFERRED EMBODIMENT
A microkernel architecture may be used to create a GUI suitable for use in environments covering a wide range of hardware capabilities. To successfully implement a microkernel GUI, it is necessary to employ a microkernel OS having IPC as lean and efficient as possible, since the communicating components of the resulting GUI will be using these IPC services so heavily. The QNX™ (Trademark of QNX Software Systems Ltd.) OS is a suitable microkernel OS for this purpose. Using an OS with low-overhead IPC, it becomes possible to structure a GUI as a graphical "microkernel" process with a team of cooperating processes around it, communicating via that fast IPC.
Running under the microkernel OS, the present invention implements only a few fundamental primitives, from which the higher level functionality of a windowing system is constructed by external, optional processes. Windows do not exist for the present invention itself, nor does the present invention possess the ability to "draw" anything, or manage a pen, mouse or keyboard. Instead, the present invention creates a virtual "Event Space" and confines itself only to managing "Regions" owned by application programs and performing the clipping and steering of various "Events" as they flow through the Regions in this Event Space. This abstraction is parallel to the concept of a microkernel OS not being capable of filesystem or device I/O, instead relying on external processes to provide these higher-level services. As in a microkernel OS, this allows a microkernel GUI to scale in size and functionality by including or excluding services as needed.
The core microkernel abstraction implemented by the present invention is that of an virtual, graphical, three dimensional Event Space that other processes can populate with Regions. These other processes use the native OS IPC to communicate with the present invention, and manipulate their Regions to provide higher-level services usable by other processes, or act as user applications using those services. By removing service-providing processes, the GUI can be scaled down for limited-resource systems. By adding service-providing processes, the GUI can be scaled up to full desktop functionality. The underlying efficiency of the OS IPC and the architecture of the present invention enables the efficiency and performance requirements for low-end embedded and PDA hardware, while also meeting the scalability and flexibility needs for larger desktop and distributed systems.
The present invention uses a number of data structures to represent the entities that populate the Event Space. Data structures for Events and Regions are processed by various algorithms to achieve the required behaviour. This will be further explained below.
The Event Space
A central characteristic of the present invention is the way in which graphical applications are represented. As indicated in FIG. 1, in the microkernel GUI, all applications exert an influence on the environment through one or more rectangles called Regions (10), which are owned by their respective processes. These Regions reside in an abstract, three-dimensional Event Space (12) where the user (14) can be imagined to be outside of this space, looking in. Regions can emit and collect objects called Events. These Events can travel in either direction through the Event Space (12) (i.e. either toward or away from the user (14)). As Events move through the Event Space (12), they interact with other Regions--this is how applications interact with each other. The process maintaining this simple architecture is the present invention's microkernel.
All the services required for a windowing system, including window managers, device drivers, and applications, can easily be created by using Regions (10) and Events and, because processes whose Regions are managed by the present invention's microkernel need not reside on the same computer as the microkernel, it is also easy to implement network-distributed applications.
Regions and Events
The two basic objects used by microkernel GUI programs are Regions (10) and Events. Regions are stationary, while Events move through the Event Space (12). A Region is a single, fixed rectangular object that a program places in the Event Space (12). A. Region possesses attributes that define how it interacts with Events. A Region is described by a data structure containing a number of elements. Each of these elements defines a specific aspect of the Region.
An Event is a set of non-overlapping rectangles that can be emitted and collected by Regions (10), in either direction (towards or away from the user), in the Event Space (12). All Events have a type associated with them. Some types of Events also possess corresponding data.
Events
As an Event flows through the Event Space (12), its rectangle set intersects with Regions (10) placed in the Event Space by other applications. As this occurs, the present invention's microkernel adjusts the Events rectangle set according to the attributes of the Regions with which the Event intersected.
Events come in various classes and have various attributes. An Event is defined by an originating Region, a type, a direction, an attached list of rectangles and optionally, some Event-specific data. Unlike other windowing systems, that only have input events such as pen, mouse, keyboard and expose, both input (pen, mouse, keyboard, expose, etc.) and output (drawing requests) are classified as Events. Events can be generated either from the Regions that programs have placed in the Event Space, or by the present invention itself. Events are used to represent the following:
key presses, keyboard state information
mouse button presses and releases
pointer motions (with or without mouse button(s) pressed)
Region boundary crossings
Regions exposed or covered
drag operations
drawing functions
Initial Rectangle Set
The initial rectangle set of an emitted Event consists of a single rectangle whose dimensions are usually the size of the emitting Region. As the Event moves through the Event Space, its interactions with other Regions may cause some portions of this rectangle to be removed, as shown in FIG. 2. (16). If this happens, the rectangle will be divided into a set of smaller rectangles (16) that represent the remaining area. Certain types of Events (e.g. mouse button presses) have no need for their initial rectangle set to have the dimensions of the emitting Region. For such Events, the rectangle set consists of a single rectangle whose size is a single point (upper left corner is the same as the lower right corner). A single-point rectangle set is called a Point Source.
Collected Rectangle Set
The rectangle set of a collected Event contains the rectangles that result from the interaction of the Event with prior Regions in the Event Space (16). If an Event is completely occluded by other Regions such that it results in a set containing no rectangles, then that Event ceases to exist.
Regions
A process may create or use any number of Regions (10), placed within the Event Space (12). Furthermore, by controlling the dimensions, attributes and location (relative to the other Regions in the Event Space), a process can use, modify, add, or remove services provided by other Regions.
A Region's owning process and the present invention can be on different, network-connected, computers. A Region has two attributes that control how Events are to be treated when they intersect with a Region and these are known as Sensitivity and Opacity. These can be set independently for each different type of Event.
Sensitivity
If a Region is sensitive to a particular type of Event (Sensitive), then the Region's owner collects a copy of any Event of that type which intersects with the Region. If other Regions are Sensitive to this same Event type and the Event intersects with them, they will also collect a copy of the Event but with a potentially different rectangle set, depending on which other Regions the Event may have interacted with. Although many Regions can collect a copy of the same Event, the rectangle set for the Event may be adjusted, and hence may be unique for each Region that collects the Event. As shown in FIG. 2, the rectangle set reflects the Event's interaction with other Regions in the Event Space before arriving at the collecting Region. If a Region is not Sensitive to an Event type, the Region's owner never collects that type of Event.
The sensitivity attribute neither modifies the rectangle set of an Event nor does it affect the Event's ability to continue flowing through the Event Space.
Opacity
Regions Opaque to a specific Event type block portions of that type of Event's rectangle set from travelling further in the Event Space. The opacity attribute controls whether an Event's rectangle set is adjusted as a result of intersecting with a Region.
If a Region is Opaque to an Event type, any Event of that type which intersects with the Region has its rectangle set adjusted, to clip out the intersecting area. The "clipped out" rectangles are modified in the Event's list of rectangles, such that the list describes only portions of the Event that continue past the Opaque Region. This changes the Event's rectangle set such that it includes more, smaller rectangles. The new rectangles describe the portions of the Event that remain visible to Regions beyond this Region in the Event Space. If a Region is not Opaque to an Event type, then Events of that type never have their rectangle set adjusted as a result of intersecting with that Region. Such a Region is said to be "Transparent" to the Event type.
The best way to illustrate how this clipping is performed is to examine the changes in the rectangle list of a draw Event as it passes through various intersecting Regions. As shown in FIG. 2, when the draw Event (16) is first generated, the rectangle list consists of only a single, simple rectangle describing the Region that the Event originated from.
If the Event goes through a Region (10A) that clips the bottom left corner out of the draw Event, the rectangle list is modified to contain only the two rectangles that would define the area remaining to be drawn.
In a similar manner, every time the draw Event intersects a Region Opaque to draw Events, the rectangle list will be modified to represent what will remain of the draw Event after the Opaque Region has been "clipped out". Ultimately, when the draw Event arrives at a graphics driver's Region ready to be drawn, the rectangle list will precisely define only the portion of the draw Event that is to be rendered (hence, visible).
If the Event is entirely clipped by the intersection of an Opaque Region, the draw Event will cease to exist. This mechanism of "Opaque" windows modifying the rectangle list of a draw Event is how draw Events from an Underlying Region (and its attached process) are properly clipped for display as they Ravel towards the user.
Attribute Summary
The following table summarizes how a Region's attributes affect Events that intersect with that Region:
______________________________________If the Region is: then the Event is: and the rectangle set is:______________________________________Insensitive, Transparent ignored unaffectedInsensitive, Opaque ignored adjustedSensitive, Transparent collected unaffectedSensitive, Opaque collected adjusted______________________________________
Insensitive, Opaque: The Event is clipped by the Region as it passes through, but the Region owner is not notified. For example, most applications would use this attribute combination for draw Event clipping, so that an application's window would not be overwritten by draw Events coming from underlying windows.
Sensitive, Transparent: A copy of the Event will be sent to the Region owner, and the Event will continue, unmodified, through the Event Space. A process wishing to log the flow of Events through the Event Space could use this combination.
Sensitive, Opaque: A copy of the Event will be sent to the Region owner, and the Event will also be clipped by the Region as it passes through. By setting this bitmask combination, an application can act as an Event filter or translator. For every Event received, the application can process and regenerate it, arbitrarily transformed in some manner, possibly travelling in a new direction, and perhaps sourced from a new coordinate. In the Event Space.
Event Logging
By placing a Region across the entire Event Space, a process can intercept and modify any Event passing through that Region. If a Region is Sensitive to all Events, but not Opaque, it can transparently log all Events.
Event Transformation
If a Region is Sensitive and Opaque, it can choose to re-emit a modified version of the Event. We refer to this as "transformation". For example, a Region could collect pointer Events, perform handwriting recognition on those Events, and then generate the equivalent keyboard Events.
The Root Region
A special Region called the root Region (20) is always the Region furthest away from the user (14), as illustrated in FIG. 4. All other Regions descend in some way from the root Region (20). Once an Event travelling away from the user (14) reaches the root Region, it ceases to exist. The dimensions of the root Region are the entire width and height of the present invention's coordinate space. As a result of the Parent/Child relationship of all Regions, the location and position of any Region is ultimately related to the location of the root Region. A Region can be located anywhere in the Event Space and yet have the root Region be its Parent.
Coordinate Space
All Regions reside within the coordinate space, whose dimensions are as shown in FIG. 3. These dimensions an: range from +32768 to -32767 in the X dimension and to a similar range in the Y dimension. The Z dimension is not numerically bound.
In contrast to the typical cartesian layout, the lower-right quadrant (19) is the (+,+) quadrant, as illustrated in FIGS. 3 and 12.
The root Region (20) has the same dimensions as the entire coordinate space. As a rule, graphics drivers map the display screen to the location shown in FIG. 12 and place the Region origin at the upper-left corner of the display screen (50). (Graphics drivers equate a single coordinate to a single pixel value on a display screen).
Region Coordinates
When an application specifies coordinates within a given Region, these are relative to the Region's origin. The application specifies this origin when it opens the Region.
The initial dimensions of a Region (i.e. rect argument in PhRegionOpen) are relative to its origin. These dimensions control the range of the coordinates that the application can use within the Region.
Some examples are provided below to show the relationship between a Region's origin and its initial rectangle coordinates. These examples illustrate how opened Regions are placed in relation to the root Region, which has its origin in the center of the coordinate space (see FIG. 3, (18)).
As a rule, applications use the following approach for Regions (See FIG. 13)
Coordinates:
Origin (51)=(0,0)
Upper left of initial rectangle (52)=(0,0)
Lower right of initial rectangle (54)=(100,100)
The following example is illustrated in FIG. 14 and shows an approach typically used for Regions that fill the entire coordinate space. For example, for the workspace Region, the upper left is (-32000,-32000) and the lower right is (32000,32000).
Coordinates:
Origin (57)=(0,0)
Upper left of initial rectangle (56)=(-50,-50)
Lower fight of initial rectangle (58)=(50,50)
The following example is illustrated in FIG. 15 and shows how a Child's origin (60) can differ from its Parent's origin (62).
Coordinates:
Origin (60)=(50,-50)!
Upper left of initial rectangle (64)=(0,0)
Lower fight of initial rectangle (66)=(100,100)
Coordinates are always relative to a Region. Thus, when a Region is moved, all its Children automatically move with it. Likewise, when a Region is destroyed, its Children are destroyed.
To become larger than any of its ancestors, a Region must make itself a Child of the root Region using PhRegionOpen() or PhRegionChange(). This action severs the Region's relationship with its former Parent.
Regions and Event Clippings
A Region can emit or collect Events only where it overlaps with its Parent. Thus, while Events can be emitted or collected anywhere in the Child Region (68) shown in FIG. 16., the Child Region can emit or collect Events only in the smaller area that overlaps with the patent Region (72), as illustrated in FIG. 17 (in grey).
Because of this characteristic of Regions, any portion of a Region that doesn't overlap its Parent is effectively invisible.
Placement and Hierarchy
In fire present invention, every Region has a Parent Region. This Parent-Child relationship results in a Region hierarchy with the root Region at the top. FIG. 18 shows the hierarchy of a typical system in accordance with the present invention.
As illustrated in FIG. 19, the present invention's microkernel always places Child Regions (74) in front (i.e. on the user (14) side) of theft Parents (76).
When pinning a Region, an application specifies the Region's Parent. If an application opens a Region without specifying its Parent, the Region's Parent is set to a default--basic Regions become Children of the root Region (20) and windows become Children of the Window Manager's backdrop Region.
Besides having a Parent, a Region may have Brothers; that is, other Regions who have the same Parent. A Region knows about only two of its Brothers--the one immediately in front and the one immediately behind. FIG. 20 shows a Parent with three Children and the relationship that one of those Children, Region 2 (80), has with its Brothers (78, 82).
When it opens a Region (e.g. Region 2 (80) in FIG. 20), the application can specify neither, one, or both immediate Brothers. Depending on how the application specifies these Brothers, the new Region may be paced according to default rules (see below) or at a specific location.
If an application opens a Region, specifying both Brothers, and this action results in an ambiguous placement request, the resulting placement is undefined.
If an application opens a Region without specifying Brothers, the present invention's microkernel places that Region using default placement rules. In most cases, these rules cause a newly opened Region to be placed in front of its frontmost Brother, which then becomes "Brother behind" of the new Region. (To use different placement rules, a programmer can specify the Ph -- FORCED -- FRONT flag). For example, in FIG. 21, Region 1 (78) is the frontmost Region.
As shown in FIG. 22, when the application opens Region 2 (80) with default placement, Region 2 is placed in front of Region 1 (78). Region 1 becomes Region 2's "Brother behind". Region 2 becomes Region is "Brother in front".
An application uses the Ph -- FORCED -- FRONT flag when it wants a Region to remain in front of any subsequent Brothers that rely on the present invention's microkernel's default placement, as shown in FIG. 23 (78A).
As mentioned above, when a Region is opened with default placement, it's placed ahead of its frontmost Brother. However, if any Brother has the Ph -- FORCED -- FRONT flag set, then the new Region is placed behind the farthest Brother that has the Ph -- FORCED -- FRONT flag set. FIG. 24 illustrates what would happen if Region 1 had the Ph -- FORCED -- FRONT flag set.
When Region 2 is opened with default placement (80), it's placed behind Region 1 (78A), and Region 1 becomes its "Brother in front". Because Region 2 was placed using default rules, it doesn't inherit the Ph -- FORCED -- FRONT setting of Region 1.
Then, if Region 3 is opened with default placement, it is placed as illustrated in (82) of FIG. 25.
The application can set the Ph -- FORCED -- FRONT flag when it opens a Region, or later, by changing the Region's flags. The state of this flag doesn't affect how the Region itself is placed, but rather how subsequent Brothers are placed if those Brothers are opened using default placement rules. That is, the Ph -- FORCED -- FRONT state of existing Brothers doesn't affect the placement of a new Region if it's opened with specified Brother relations.
The Ph -- FORCED -- FRONT flag only affects placement among Brother Regions--a Child Region always goes in front of its Parent.
In contrast to default placement, if any Brother is specified when a Region is opened, then that specification controls the placement of the new Region. This is known as "specific placement".
If a "behind" Brother is specified, then the newly opened Region automatically is placed in front of that Brother.
If an "in front" Brother is specified, then the newly opened Region is automatically placed behind that Brother.
The Ph -- FORCED -- FRONT setting of the specified Brother is inherited by the new Region.
If an application opens a Region, specifying both Brothers, and this remits in an ambiguous placement request, then the resulting placement is undefined.
Using Regions
To open a Region, an application passes the information shown in the above diagram to the PhRegionOpen() function:
______________________________________PhRid.sub.-- t PhRegionOpen ( unsigned fields, PhRegion.sub.-- t *info, PhRect.sub.-- t *rect, void *data );______________________________________
where:
fields When a Region is opened, the present invention's microkernel sets up the Region with default values. If the fields member contains any items, then those items will be set according to their value in the info structure rather than to the default.
info Indicates the specific settings for the Region.
rect Indicates the dimensions of the Region (i.e. size and position), relative to the info->origin coordinates, which are in turn relative to the origin of info->Parent. For more information, see ti section on "Region origins".
data Contains information specific to the Region's type.
The data portion of a Region depends on that Region's type (which is specified in info->flags).
Programmers should avoid using the data portion of a Region unless intimately familiar with the implementation of that type of Region.
While a Region is always in front of its Parent, the Region's placement relative to its Brothers is flexible. See "Placement and Hierarchy" for more information about "default" and "specific" placement.
The PhRegion -- t structure, as explained further below, indicates the relationship of a Region with its siblings: bro -- in -- from--indicates the sibling immediately in front; bro -- behind--indicates the sibling immediately behind. This information can be retrieved using PhRegionQuery().
An application can specify a Region's placement when it opens the Region, or it can change the placement later on. To change a Region's placement, the application must change the relationship between the Region and the Region's family.
The application does this by doing any or all of the following:
1.) setting the Parent, bro -- front and bro -- behind members of the Ph -- Region -- t structure;
2.) setting the corresponding fields bits to indicate which members are valid (only those fields marked as valid will be acted on); and
3.) calling the PhRegionChange() function
Since an application can be sure of the position of only the Regions it owns, it should not change the position of any other Regions. Otherwise, by the time the application makes a request to change the position of a Region it doesn't own, the information retrieved by PhRegionQuery() may not reflect that Region's current position. That is, a request to change a Region's placement may not have the results the application intended.
A Region's Parent can be changed in two ways. The first and simplest way is to specify the Parent in the Parent member of the PhRegion -- t structure. This makes that Region the Parent of the Region specified in the first member of PhRegion -- t. However, if the patent is set to 0. Then the Region's Parent is set to a default. For a basic Region, the root Region becomes the Parent. For a window Region, the window manager's backdrop Region becomes the Parent.
The other way to change a Region's Parent is to specify a Child of another Parent as the Region's Brother. This makes the Region a Child of that Parent.
______________________________________If you set: then:______________________________________bro.sub.-- behind the Region indicated in the rid member of PhRegion.sub.-- t moves in front of the bro.sub.-- behind Regionbro.sub.-- in.sub.-- front the Region indicated in the rid member of PhRegion.sub.-- t moves behind the bro.sub.-- in.sub.-- front Region______________________________________
As discussed in Changing the Parent, a Region inherits the Parent of an specified Brothers that are Children of another Parent.
Using Events
To emit an Event, an application passes the information shown in the above diagram to the PhEventEmit() function:
______________________________________PhEventEmit ( PhEvent.sub.-- t * event, PhRect.sub.-- t * rects, void* data );______________________________________
where:
event Includes several members, some set by the application emitting the Event, and others by the present invention's microkernel. The application must set the following members:
type Type of Event.
subtype Event subtype (included if necessary).
flags Event modifiers (e.g. direction).
emitter ID of the Region that will emit the Event.
translation Typically set to 0 (see chapter on data structures in Programmer's Reference).
num -- rects Indicates the number of rectangles in reels. If the application sets num -- rects to 0, it must also set reels NULL.
The present invention's microkernel sets the following members:
timestamp The time when this Event was emitted (in seconds).
collector ID of the collecting Region.
rects An array of rectangles indicating the Event's initial rectangle set. If the application sets rects to NULL, the initial rectangle set defaults to a single rectangle that has the dimensions of the emitting Region (i.e. event->emitter).
data Valid data for the type of Event being emitted. Each type has its own type of data. See the section on "Event Types".
Sometimes an application needs to target an Event directly at a specific Region without making the Event travel through the Event space before arriving at that Region. To ensure that the targeted Region sees the Event, the application must:
1.) set the emitter member of the PhEvent -- t structure to the ID of the target Region-this causes the Event to be emitted automatically from that Region; and
2.) set Ph -- EVENT -- INCLUSIVE on the event--this causes the present invention's microkernel to emit the Event to the emitting Region before emitting it into the Event space.
If a targeted Event is not to continue through the Event space, the emitting Region must be made opaque to that type of Event.
When an Event is emitted, the coordinates of its rectangle set are relative to the origin of the emitting Region. But when the Event is collected, its coordinates become relative to the origin of the collecting Region. The present invention's microkernel ensures this happens by translating coordinates accordingly.
To collect Events, applications call PhEventRead() or PhEventNext(). The PhGetRects() function extracts the rectangle set and PhGetData() extracts the data portion of the Event.
A Region can collect Events only if portions of its Region overlap with the emitting Region.
Event Compression
The present invention's microkernel compresses drag, boundary, and pointer Events. That is, if one of these types of Events is pending when another arrives, the new one will overwrite it. As a result, an application sees only the latest values for these Events and is saved from collecting too many unnecessary Events.
How Region Owners are Notified of Events
Region owners can be notified of Events by the present invention in three different ways: they can either poll, use synchronous notification, or asynchronous notification. To poll, the application calls a function that asks the present invention to reply immediately with either an Event or a status indicating no Event is available. Although polling should be avoided in multitasking systems, it may be beneficial on occasion. For example, an application rapidly animating a screen can poll for Events as part of its stream of draw Events. An application can also use polling to retrieve an Event after an asynchronous Event notification (see below).
For synchronous notification, the application calls a function that asks the present invention to reply immediately if an Event is pending, or if none is available, to wait until one becomes available before replying. With synchronous notification, an application cannot block on other sources while it is waiting for the present invention to reply. This behaviour should be acceptable in most cases since it causes the application to execute only when the desired Events become available. If for some reason the possibility of blocking on the present invention is not acceptable, asynchronous notification may be considered.
For asynchronous notification, the application calls a function that sets up a notification method (i.e. a signal or a proxy) that the present invention activates when an Event of the desired type is available. The application can then retrieve the Event by polling. With asynchronous notification, an application can block on multiple sources, including processes that aren't applications within the GUI.
Input Manager
The present invention's Input Manager (Photon.input) is a process which places a Region near the front of the Event Space, just behind the graphics drivers. It collects data from input devices such as the keyboard, mouse and pen. As input from these hardware devices occurs, Photon.input injects the corresponding Events into the Event Space. For pointing device input (pen and mouse), as the pen and mouse Events are injected into the Event Space, Photon.input also emits draw Events for a mouse or pen cursor out towards the user, where they will intersect a graphics driver Region, resulting in a mouse or pen cursor becoming visible on the screen as the corresponding input device is moved.
Device Drivers
In the present invention, device drivers aren't inherently different from other applications. They're simply programs that use Regions and Events in a particular way to provide their services. As with a microkernel OS, this allows device drivers to be easily started and stopped at runtime, and to be developed with the same tools (and ease of development) as application programs.
Depending on its function, a driver is either an "input driver" or an "output driver". For example, the mouse and keyboard drivers tend to be classified as input drivers since they emit, and are the source of, hardware actions. As illustrated in FIG. 8, graphics (38) and printer drivers, on the other hand, tend to classified as output drivers since they collect Events (40) that cause them to take action with hardware devices.
Input Events
No assumption is made by the present invention as to what a pointing device or keyboard is. The process injecting mouse, pen or keyboard Events could interface to any arbitrary hardware or process, and collect data which it transforms into the corresponding input Events.
Many keyboard-less graphical applications have the need to "pop-up" a visual keyboard that the user can operate by "tapping" time displayed keys. By creating this keyboard as a Region that accepted mouse and pen Events, and transforms those Events into key Events "injected" into the Event Space, any application could use this keypad without explicit programming effort. In a similar manner, an application that reads A/D data representing speech from a /dev/audio resource manager could perform voice recognition on the data and inject the equivalent keystrokes into the system, all without application modifications.
Graphics Driver
A graphics driver places a Region (38) Sensitive to draw Events (40) into the Event Space. As the driver collects draw Events, it renders the graphical information on the screen. Because the collected Event's rectangle set contains only those areas that need to be updated, the driver can optimize its update. This is especially efficient if the graphics hardware can handle clipping lists directly. The present invention's drawing API accumulates draw requests into batches that are emitted as single draw Events. The job of e graphics driver is to transform this clipped draw list into a visual representation on-whatever graphics hardware the driver is controlling.
An advantage to delivering a "clip list" within the Event passed to the driver is that each draw request then represents a significant "batch" of work. As graphics hardware advances, more and more of this "batch" of work can be pushed directly into the graphics hardware. Many display controller chips already handle a single clip rectangle; graphics hardware at handles multiple clip rectangles is imminent.
Multiple Graphic Drivers
From an application's perspective, the coordinate space always looks like a single, unified graphical space, yet it allows users to drag windows from one physical screen to another. Since graphics drivers simply put a Region into the Event Space, and that Region describes an X by Y space to be intersected by draw Events, it naturally follows that multiple graphics drivers can be started, each controlling a different graphics controller card, with their draw-Sensitive Regions present in the same Event Space. These multiple Regions could be placed physically adjacent to each other, as shown in FIG. 7 describing an array of "drawable" tiles (38). or overlapping in various ways. With a suitable underlying OS, such as QNX™, providing network transparency, applications or drivers can run on any node, allowing additional graphics drivers to extend the graphical space of the present invention to the physical displays of many networked computers. By having the graphics driver Regions overlap, the draw Events can be replicated onto multiple display screens.
Many interesting applications become possible with this capability. One is that an operator in a factory could walk up to a desk top computer with a wireless-LAN PDA in their hand, drag a window from a plant control screen onto the PDA, and walk out onto the plant floor, able to interact with the control system to monitor and adjust the plant-floor equipment they may be inspecting. This also enables useful collaborative modes of work for people using multiple PDA's, such that a group of people can simultaneously see the same application screen on their PDA's, and cooperatively operate the application. This approach is ideally suited for support or training environments.
From the application's perspective, this looks like a single, unified graphical space. From the user's perspective, this allows windows to be dragged from physical screen to physical screen, even across the network links.
Remote Screen Viewing
Another useful facility is the ability to view a remote graphical desktop and manipulate it as if it was local. This is known as "Ditto" and is useful for remote diagnostics, technical support/training, collaborative team work, and many other situations. A problem with implementing such an application for graphical environments is that graphical screens contain potentially megabytes of pixel data, requiring a large bandwidth to relay the screen image, as well as large amount of processor and memory overhead to compare previous screen images with current screen images in an attempt to send only differences, minimizing the bandwidth requirement. Typically, hardware constrained platforms, such as PDAs and embedded systems, lack the processor, memory and communications bandwidth to support a pixel-copying Ditto effectively. Using the present invention and a suitable underlying OS, this is easily done.
A Ditto is implemented as a Transparent, draw-Event-Sensitive Region placed in front of the entire screen (or a single application Region). As draw Events come out of the Event Space and transparently pass through the ditto Region, a copy of the draw Events would be received by the Ditto process. This Ditto process would also own a Region in another the present invention Event Space, on another node in the network. In that Event Space, the draw Event would be regenerated; travelling out towards a graphics driver where the same draw list as on the first system would be processed and drawn. In a similar manner, keyboard, pen and mouse Events entering the Ditto Region in the second Event Space could be relayed across and regenerated in the Event Space being monitored. The advantage of this approach is that draw Events require a much lower bandwidth than pixel copying and comparing. The Ditto is functional across low-bandwidth links even though its core functionality can be expressed in less than 160 lines of C, or less than 1 Kbyte of code.
Primer Driver
To print an area of the coordinate space, the printer driver inserts a Region that is Opaque to draw Events in front of tie area of the coordinate space to be printed. This prevents draw Events from reaching the graphics driver. The printer driver then emits an expose Event toward the Region being printed, waits to collect draw Events from that Region, and renders them on the printer. Once the draw Events are completed, the Region is removed, without having caused a visible redraw on the screen.
This scheme permits printing of any Region, even if the Region is blocked by others in the Event Space. Also, the printer driver could emit its own draw Events toward the user to indicate a printing operation is in progress.
Since the printer driver collects draw Events, it can translate them into the format necessary for different types of print devices. For example, when using a PostScript printer, draw Events could be translated directly into commands that take full advantage of the printer's resolution. Since the draw Events being translated are high-level draw requests, they can be rendered on the print device at full printer-resolution, rather than with the coarse pixelation that results from a green-resolution "pixel dump".
Encapsulation Drivers
Since graphics drivers are really just applications to the present invention, they can be applications displaying their graphical output inside another windowing system. A driver could also take the keyboard and mouse Events it collects from the other windowing system and regenerate them within the Event Space, allowing the window in the other system to be fully functional, both for graphical display and for keyboard/mouse input,
Window Manager
The window manager is an optional application that manages other Regions. It provides the windowing system with a certain look and feel.
The window manager also manages the workspace, supplements the methods for focusing keyboard Events, and displays a backdrop. To provide all these services, the window manager places several Regions in the Event Space, namely:
window Regions;
a focus Region;
a workspace Region; and
a backdrop Region.
Colour Model
Colours processed by the graphics driver applications are defined by a 24 bit RGB (red-green-blue) quantity, 8 bits for each of red, green, total range of 16,777,216 colours. Depending on the actual display hardware managed by the graphics driver applications, the driver will either invoke the 24-bit colour directly from the underlying hardware, or use various dithering techniques to create the requested colour from less-capable hardware. Since the graphics drivers use a hardware-independent colour representation, application can be displayed without modifications on hardware possessing varied colour models. This allows applications to be "dragged" from screen to screen without concern for what the underlying display hardware's colour model might be.
Window Regions
Most applications rely on the windowing system to provide the user with the means to manipulate their on-screen size, position, and state (i.e. open/configured). So the user can perform these actions, the window manager puts a frame around the application's Region and then places gadgets in that frame (e.g. resize corners, title bars, buttons). These gadget services are referred to as "window services". To indicate it can provide window services, the window manger registers with the present invention. As shown in FIGS. 8-11, when an application opens a window, the window manager sets up two Regions on its behalf: namely a window Region (42) and an application Region (26). The window Region is slightly larger than the application Region and is placed just behind it.
The application uses the application Region (26) while the window manager uses the window Region (42) for its gadgets. The application isn't aware of the window Region or the gadgets drawn on it. If the user uses the gadgets to move the application, the application notices only that its location has changed. The same goes for resizing, iconifying, and so on.
Focus Region
By placing a Region of its own (the focus Region (44)) into the Event Space, the window manager can intercept these keyboard Events as they are emitted from Photon.input's Region and implements an input focus method.
The window manager can redirect keyboard Events to Regions not directly beneath the screen pointer. For example, it can focus Events toward the last window the user "clicked" on (i.e. The active window). The window manager can direct keyboard Events to that active Region even if the Region gets covered by another Region.
Workspace Region
From the user's perspective, the workspace is the empty space surrounding the windows on the screen. As shown in FIGS. 10-11, the window manager places a workspace Region just in front of the root Region to capture pointer Events before they get to the root Region and thus disappear. When the user presses a pointer button and no other Region collects the Event, the window manager brings up a workspace menu that lets the user select a program to run.
Backdrop Region
Users often like to have an ornamental backdrop image displayed behind the windows on the screen. To display such a bitmap, the window manager places a backdrop Region (48) in the Event Space as illustrated in FIG. 11.
Responsibilities of Microkernel
The present invention's microkernel performs a small set of operations from which the processes that surround the microkernel can construct a windowing system. Those functions are:
1.) Maintaining a Region hierarchy as a set of data structures within the present invention's microkernel. The actions associated with maintaining the Region hierarchy are:
a) Opening Regions
b) Changing the characteristics of Regions
c) Closing Regions
These actions are described in more detail in a following section.
2.) Emitting Events. Emitting an Event entails accepting the emit request from a process which owns a Region in the Event Space and then traversing the linked list of data structures that describes the Regions in the Event Space in the direction indicated in the Event (to front, or to back) and examining each. Region to test for an intersection, and if so, to apply the actions indicated by the sensitivity and opacity bits within the intersected Region.
3.) Maintaining an Event queue for each client. The actions associated with this maintenance include:
a) Enqueuing Events for the processes which own Regions.
b) Dequeuing Events to the processes which own Regions.
c) Client-controlled throttling to prevent queue overflows.
4.) Responding to queries. Processes which own Regions have the ability to make miscellaneous queries of the present invention's microkernel including:
a) Querying about a Region or a Region type
b) Querying about a client process
c) General statistics
Data Types:
The present invention's API uses the following data structures:
PhPoint -- t the coordinates of a single point
PhRect -- t the coordinates of a rectangle
PhArea -- t the position and dimensions of a rectangular area
PhEventRegion -- t the emitter and the collector of an Event
PhEvent -- t an Event
PhRegion -- t a Region
1.) PhPoint -- t Structure
The PhPoint -- t structure describes the coordinate of a single point. It contains at least the following members:
short x; x-axis coordinate
short y; y-axis coordinate
2.) PhRect -- t Structure
The PhRect -- t structure describes the coordinates of a rectangle. It contains at least the following members:
PhPoint -- t ul; upper-left corner
PhPoint -- t lr; lower-right corner
3.) PhArea -- t Structure
The PhArea -- t structure describes the position and dimensions of a rectangular area. This structure contains at least the following members:
PhPoint -- t pos; upper-left corner of the area
PhPoint -- t size; x value specifies width of the area and y value specifies height of the area
4.) PhEventRegion -- t Structure
The PhEventRegion -- t structure describes the emitter and the collector of Events (see PhEvent -- t). It contains at least the following members:
PhRid -- t rid; The ID of a Region. This lets an application determine which of its Regions emitted or collected an Event.
long handle; The user-definable handle that the application specifies when it opens the Region. Applications can use handle m quickly pass a small mount of information along with Events.
If the Region described by a PhEventRegion -- t structure isn't owned by the application that collected the Event, then the present invention's microkernel sets handle to 0.
5.) PhEvent -- t Structure
The PhEvent -- t structure describes an Event. It contains at least the following members:
unsigned long type; Contains the Event type, thus indicating how to interpret the data associated with the Event. Setting more than one type for an Event is invalid. For the possible values of type, see the section on Event Types.
unsigned short subtype; Contains further information about the Event.
PhEventRegion -- t emitter; Specifies which Region will emit the Event. An application can emit an Event from a Region it doesn't own by setting emitter to the ID of that Region. Applications can use this approach when they target the device Region by setting the Ph -- EVENT -- INCLUSIVE flag.
PhEventRegion -- t collector; Indicates which Region collected the Event. When a process has many Regions open, collector lets the process distinguish which of its Regions was involved.
unsigned short flag; Contains event-modifier flags. At least the following flags are defined. A programmer can OR the following values into flags:
Flag
Effect
Ph -- EMIT -- TOWARD Emits the Event toward the user. By default, Events are emitted away from the user.
Ph -- EVENT -- ABSOLUTE Forces the rectangle set associated with the Event to be relative to the root Region's origin. By default, the coordinates of the rectangle set are relative to the origin of the emitting Region.
Ph -- EVENT -- INCLUSIVE Forces the present invention's microkernel to emit the Event first to the emitting Region, and then through the Event Space. Using this, an application can guarantee that the emitter will see the Event (assuming the emitting Region is Sensitive to that event type). time -- t timestamp;. Indicates when the Event was emitted. Specified in seconds.
PhPoint -- t translation; The translation between the emitting Region's origin and the collecting Region's origin. An application uses this member to convert coordinates that are relative the emitter's Region to coordinates that are relative to collector's Region. For example, let's say the graphics driver wishes to render Ph -- EV -- DRAW Events. When these Events reach the driver, they contain coordinates relative to the Region that emitted them. To render these Events within its own Region, the graphics driver uses translation to convert the coordinates.
unsigned short num -- rects; Indicates the number of rectangles associated with the Event.
unsigned short data -- len; Indicates the length of the data associated with the Event. Since Event data is optional, a programmer can set data -- len to 0. To extract the data from an Event, see PhGetData().
5.) PhEvent -- t Structure: Event Types
A programmer can OR the following Event types into the type member of the PhEvent -- t structure:
Ph -- EV -- KEY Is emitted when a key state changes (e.g. the user presses or releases a key). This Events rectangle set consists of a point source indicates the current keyboard focus. The Event data is a PhKeyEvent -- t structure that contains at least the following members:
long key -- code; Key value.
long key -- state; Key-state modifier (e.g. Up, Down, Shift, Alt, Ctrl).
unsigned short key; ASCII value of key. Valid only if Pk -- KS -- ASCII -- Valid is set in key -- state.
long raw -- key -- code; Key code, without modifier.
Ph -- EV -- BUT -- PRESS Emitted when the user presses a button on a pointing device. This Event's rectangle set consists of a point source that indicates the current pointer focus. The Event data is a PhPointerEvent -- t structure that contains at least the following members:
PhPoint -- t pos; Indicates the untranslated, absolute position of the current pointer focus. As a rule, a programmer should use the Event's rectangle set to determine coordinate positions. However, for situations that demand absolute coordinates (e.g. calibrating a touchscreen), a programmer can use pos.
unsigned short click -- count; Indicates the number of clicks (e.g. a value of 2 indicates a double-click).
short dz; Indicates touch pressure. Used with touchscreens.
long buttons; Indicates which buttons the user pressed. For convenience, the following manifests have been defined:
Ph -- BUTTON -- SELECT normally the left button. Because a pointing device may provide this button only, a programmer should design most applications such that the user has the option to use this button to perform any task.
Ph -- BUTTON -- MENU can be used to invoke menus when they're available.
Ph -- EV -- BUT -- REPEAT Emitted when the user presses on an auto-repeating button on a pointing device. This Event is emitted each time the button repeats. This Event's rectangle set consists of a point source that indicates the current pointer focus. The Event data is a PhPointerEvent -- t structure (see Ph -- EV -- BUT -- PRESS).
Ph -- EV -- BUT -- RELEASE Emitted when the user releases a pointing-device button. This Event's rectangle set consists of a point source that indicates the current pointer focus. The Event data is a PhPointerEvent -- t structure (see Ph -- EV -- BUT -- PRESS). However, in this case, the buttons member indicates the button that was released, not the on that was pressed.
Ph -- EV -- PTR -- MOTION Emitted when the user moves the pointing device. This Event's rectangle set consists of a point source that indicates the current pointer focus. The Event data is a PhPointerEvent -- t structure (see Ph -- EV -- BUT -- PRESS).
Large numbers of Ph -- EV -- PTR -- MOTION Events can slow down system performance. To avoid this applications should be made Sensitive to Ph -- EV -- PTR -- MOTION -- BUTTON whenever possible, rather than to Ph -- EV -- PTR -- MOTION.
Ph -- EV -- PTR -- MOTION -- BUTTON Emitted when the user moves the pointing device while pressing a button. This Event's rectangle set consists of a point source that indicates the current pointer focus. The Event data is a PhPointerEvent -- t structure (see Ph -- EV -- BUT -- PRESS). The buttons member indicates which buttons the user is pressing.
Ph -- EV -- BOUNDARY Emitted when the pointer crosses Region boundaries. The subtype member of the PhEvent -- t structure indicates one of the following boundary conditions:
Ph -- EV -- PTR -- ENTER Emitted when the pointer enters a Region. By default, enter Events are emitted to the frontmost Region that's under the pointer but only if that Region is also Opaque or Sensitive to Ph -- EV -- EXPOSE Events. Nevertheless, an application can force the present invention's microkernel to emit boundary Events to the frontmost Region under the pointer, without regard for that Region's sensitivity or opacity to Ph -- EV -- EXPOSE. To do so, the application sets the Region's Ph -- FORCE -- BOUNDARY flag.
Before entering a Region, the pointer usually first enters the ancestors of that Region. But with some pointing devices (e.g. touchscreens), the pointer may bypass the ancestors and enter the Region directly. If this happens, the present invention's microkernel emits an enter Event to the Region as well as to its ancestors.
Ph -- EV -- PTR -- LEAVE Emitted when the pointer leaves a Region. A leave condition occurs only when the pointer enters a Region that's not a Child of the previously entered Region. (Child Regions are always located within the bounds of their Parents. Thus; the pointer doesn't have to leave a Parent to enter its Child. )
Ph -- EV -- EXPOSE Emitted by the present invention's microkernel on behalf of a Region being moved, resized, or removed from the Event Space. The Event travels away from the user and appears to originate from the removed Region. Since any Regions now exposed will see the expose Event, an application can determine which of its Regions have been uncovered. It can then redraw any portion of the Regions that become visible by passing the rectangle set to PgSetClipping(). This Event's rectangle set describes those areas that are now exposed. This Event has no associated data.
Ph -- EV -- COVERED Emitted by the present invention's microkernel when a Region is created. The Event travels away from the user and appears to originate from the newly created Region. Since any Regions now covered by the new Region will see the covered Event, an application can use this Event to determine if its Regions are partially coveted. With this information, the application can then take appropriate action. For example, an animation program that consumes many processor cycles might choose to cease animation when covered, men resume animation when exposed again. The rectangle set of this Event describes only those areas that have become covered. This Event has no associated data. Ph -- EV -- DRAW Emitted by the Pg* functions when applications perform draw operations. The Event travels toward the user and is collected by the graphics driver. The Event has the same rectangle set as the emitting Region. The Event data is a PhDrawEvent -- t structure that contains at least the following members:
Unsigned short emd -- buffer -- size; Size of the draw buffer, in bytes.
unsigned short context -- size; Portion of the draw buffer that represents the current draw context.
unsigned long id; ID number (unique for each application in this space). The Pg* functions set this number and use it to optimize draws.
Ph -- EV -- DRAG Used by an application to initiate drag Events, to determine their completion, and to indicate intermediate drag-motion Events. This Event can have any of the following subtypes:
Ph -- EV -- DRAG -- INIT To initiate a drag operation, an application must target a Ph -- EV -- DRAG Event (with this subtype) at the device Region. The present invention's microkernel takes care of the user's interaction with the screen pointer and the drag outline. The PhInitDrag() function provides a convenient way to initiate drag operations (it emits Ph -- EV -- DRAG -- INIT).
Ph -- EV -- DRAG -- COMPLETE When the user completes the drag operation, the device Region emits a Ph -- EV -- DRAG Event (with this subtype) toward the root Region so that the initiating application collects the Event.
Ph -- EV -- DRAG -- MOVE Indicates intermediate drag motion. The present invention's microkernel emits this drag-Event subtype if the Ph -- DRAG -- TRACK flag was set in the flag member of the PhDragEvent -- t structure when the drag operation was initiated. The rectangle set of drag Events doesn't contain any useful value. The Event data is a PhDragEvent -- t structure that contains at least the following members:
PhRid -- t rid; Indicates the Region that initiated the drag operation. The application needs to set rid when the drag is initiated.
ushort flags; Indicates which edges of the drag rectangle will track with the pointer. A programmer can OR the following values into flags:
Ph -- TRACK -- LEFT Left edge tracks the pointer.
Ph -- TRACK -- RIGHT Right edge tracks the pointer.
Ph -- TRACK -- TOP Top edge tracks the pointer.
Ph -- TRACK -- BOTTOM Bottom edge tracks the pointer.
Ph -- DRAG -- TRACK No drag outline is drawn and Ph -- EV -- DRAG MOVE Events are emitted to the initiating Region. This flag is used by applications that wish to implement their own visual interpretation of drag operations.
PhRect -- t rect; Contains the coordinates of the initial, current, or final drag rectangle, depending on the drag-Event subtype value. This rectangle is relative to the origin of the Region specified in the rid member.
PhRect -- t boundary; Contains the coordinates of the rectangle that constrains the drag operation. This rectangle is relative to the origin of the Region specified in the rid member.
Ph -- EV -- WM Both the Window Manager and applications can emit this Event. The window manager emits this Event when the application has asked to be notified. An application can emit this Event to communicate to the window manager regarding windows. Ph -- EV -- WM can have the following subtype:
Ph -- EV -- WM -- EVENT The rectangle set of the Event has no useful value. The Event data is a PhWindowEvent -- t structure that contains at least the following members:
unsigned short event -- f; Indicates the type of the window Event. The flags a programmer can set in this member are the same as those for Pt -- ARG -- WINDOW -- MANAGED -- FLAGS and Pt -- ARG -- WINDOW -- NOTIFY. (e.g. Ph -- WM -- CLOSE, Ph -- WM -- MENU, Ph -- WM -- TERMINATE)
unsigned short state -- f; The current state of the window.
PhServerRid -- t rid; The ID of the affected Region.
short event -- state; A programmer can OR on or both of the following into event state:
Ph -- WM -- EVSTATE -- INVERSE Perform the inverse of the action specified in the Event.
Ph -- WM -- EVSTATE -- PERFORM The Window Manager has completed or has been asked to complete the requested action. If this Event is emitted to the Window Manager, the Event is performed by the Window Manager. If an application collects this Event, the Window Manager has completed the Event.
PhPoint -- t pos; For Events that use position (e.g. menus), this member indicates the position of the item.
PhPoint -- t size; For Events that use size (e.g. Resize Events), this member indicates the size of the item.
6.) PhRegion -- t Structure
The PhRegion -- t structure describes a Region. It contains at least the following members:
PgColor -- t cursor -- color; sets the cursor color for this Region. unsigned char cursor -- type; Sets the cursor type for this Region. If an application sets cursor -- type to 0, this. Region inherits the cursor from the Parent Region. If you OR cursor -- type with Ph -- CURSOR -- NO -- INHERIT, then Children of this Region won't inherit its cursor type. The Children will inherit the cursor from their first ancestor that doesn't have the Ph -- CURSOR -- NO -- INHERIT flag set.
PhRid -- t rid; The Region's unique identifier. The present invention's microkernel assigns this when the Region is opened.
long handle; A user-definable handle that forms part of the Event structure. Applications cart us handle to quickly pass a small amount of information along with Events. For example, the widget (Pt) functions use handle to point to a widget in memory so that they can quickly find the appropriate callback.
mpid -- t owner; Indicates the process ID of the owner of this Region,
unsigned short flags; Controls certain aspects of a Region and also indicates a Region's type. Of the following flags, the first two, Ph -- FORCE -- BOUNDARY and Ph -- FORCE -- FRONT, affect how a Region behaves. The others simply indicate a Region type. These type flags are set by the API functions for the convenience of applications that wish to identify a Region's purpose. For example, an application can use these flags to query the present invention's microkernel for a list of Regions that have a specific type. A programmer can OR de following into flags:
Ph -- FORCE -- BOUNDARY to force the present invention's microkernel to emit Ph -- EV -- BOUNDARY Events to this Region. If a programmer doesn't set this flag, the present invention's microkernel determines if a Region should get boundary Events by verifying that the Region is Opaque or Sensitive to Ph -- EV -- EXPOSE Events.
Ph -- FORCE -- FRONT to force the present invention's microkernel to place this Region in front of any of its Brothers that don't have this flag set, and behind any Brothers that do have this flag set.
Ph -- GRAFX -- Region to indicate the Region is Sensitive to draw Events (e.g. a graphics driver).
Ph -- KBD -- Region to indicate the Region emits keyboard Events (e.g. a keyboard driver).
Ph -- PTR -- Region to indicate the Region emits pointer Events (e.g. a pointer driver).
Ph -- WINDOW -- Region to indicate the Region is a window,
Ph -- WND -- MGR -- Region to indicate the window manager owns the Region.
unsigned long events -- sense; Determines which Event types this Region is Sensitive to. When an Event of passes through a Region that is Sensitive to it, the Event is enqueued to the application.
unsigned long events -- opaque; Determines which Event types this Region is Opaque to. When an Event passes through a Region that is Opaque to it, any portion of the Event that intersects with the Region is clipped out.
PhPoint -- t origin; Determines the Region's origin relative to its Parent's origin. All coordinates returned in Events and elsewhere in this structure are relative to origin.
PhRid -- t parent; Indicates the Region's Parent.
PhRid -- t child; Indicates the frontmost Child Region (i.e. closest to the user). If no Child Regions exist, the present invention's microkernel sets Child to 0.
PhRid -- t bro -- in -- front; Indicates the Brother Region that's located immediately in front. If there's no Brother in front, the present invention's microkernel sets bro -- in -- front to 0.
PhRid -- t bro -- behind; Indicates the Brother Region that's located immediately behind. If there's no Brother behind, the present invention's microkernel sets bro -- behind to 0.
unsigned short data -- len; Determines the length of the data portion of this Region.
Data Structures
The present invention's microkernel uses a number of data structures to represent the entities that populate the "Event Space" metaphor. Data structures for Events and Regions are processed by various algorithms within the present invention in order to give the Event Space the required behaviour.
A Region is described by a data structure containing a number of elements. Each of these elements defines a specific aspect of the Region. The names and purpose for some of the elements contained by the Region data structure are:
rid Region identification number. Every Region must have a unique number.
owner This field defines which application process owns this Region.
flags This field defines miscellaneous characteristics of the Region.
sense The array of bits that define which Event types this Region is Sensitive to.
opaque The array of bits hat defines which Event types this Region is Opaque to.
state The current state of the Region.
origin The coordinate of me upper, left corner of the Region within the Event Space.
parent The Region id of the Region which is the "Parent" of this Region in the Event Space.
child The Region id of the Region which is the "Child" of this Region in the Event Space.
bro -- in -- front The Region id of the Region which is a Brother of this Region and in front of it.
bro -- behind The Region id of the Region which is a Brother of this Region and behind it.
cursor -- color The colour of the cursor displayed over this Region.
cursor -- type The type of the cursor to be displayed over this Region.
Just as for the Region, another data structure defines an Event within the present invention's microkernel. An Event is described by a data structure Containing a number of elements. Each or these elements defines a specific aspect of the Event. The names and purpose for some of the elements contained by the Event, data structure are:
type Type of Event (mouse, keyboard, draw, expose, etc.)
Region The Region which i emitting the Event.
flags Some flags describing miscellaneous characteristics of the Event.
timestamp The time the Event was created.
translation An x,y offset used to offset the eve Event within the Event Space,
num -- rects The number of rectangles that define the Event. Normally this starts out as one, and as the Event moves through the Event Space and is split by intersecting with Opaque Regions, this rectangle count will increase in order to describe the portion of the Event which remains.
data -- len The length of the data field attached to this Event.
Pevent -- t (Photon Manager)
link -- count The number of links to this Event. This field is used to indicate whether or not this Event data structure is currently in use or not.
Application Program Interface
The API (application program interface) used by applications communicating with the present invention's microkernel consists of a few fundamental interface routines over which the remainder of the API functionality is implemented. The three interfaces which serve to demonstrate the core functionality provided by the present invention's microkernel are:
PhRegionOpen Open a Region in the Event Space.
PhEventEmit Emit an Event from a Region.
PhEventNext Wait for an Event to hit a Region in the Event Space.
A more detailed description of each of these routines follows:
1.) PhRegionOpen--Open a Region in the Event Space
This API call allows an application program to create a Region in the Event Space that can then be used to sense Events moving in the Event Space, to emit Events of the program's choosing into the Event Space, and to modify Events moving through the Event Space. The declaration for this API function takes the form:
______________________________________PhRid.sub.-- t PhRegionOpen( unsigned fields, PhRegion.sub.-- t *info, PhRect.sub.-- t *rect, void *data );______________________________________
This declaration indicates that the function returns a data type "PhRid -- t". (Photon Region id type) when the PhRegionOpen function is called. This return value will either indicate the Region id of the newly created Region, or a -1 to indicate an error. The function takes four parameters:
unsigned fields "unsigned" indicates that the "fields" parameter is an unsigned integer of the computer's native integer size. The value passed in the "fields" parameter is used in this case as a bit field, with each of the bits in the integer representing whether or not a specific element in the "info" structure (the second parameter) is set to a specific value, or should be set to a default value by the present invention.
PhRegion -- t *info The "PhRegion -- t" indicates that this parameter is a "Photon Region Structure Type", and the "*info" indicates that this is a pointer to a structure of this type. This structure is initialized in the program (before making this API call) to contain the values necessary to define the Region the application wants to create.
PhRect -- t *rect The "PhRect -- t" indicates that this parameter is a "Photon Rectangle Type", and the "*feet" indicates that this is a pointer to a structure of this type. This structure is initialized to define the rectangle associated with the Region.
void *data The "void" indicates that data pointed to by "*data" is of no specific type. This data is attached to the Region created within the present invention's Event Space.
2.) PhEventOpen--Emit an Event in the Event Space
This API call is used by an application to emit an Event from a Region in the Event Space. The declaration for this interface function takes the form:
______________________________________int PhEventEmit( PhEvent.sub.-- t *event, PhRect.sub.-- t *rects void *data );______________________________________
This indicates that the function returns a data type of "int" or integer, indicating success or failure. The function takes three parameters;
PhEvent -- t *event The "PhEvent -- t" indicates that this parameter is a "Photon Event Type" and that "*event" is a pointer to a structure of this type. The structure will have been defined within the program before making this API call. This structure defines which Event type is being sent, which direction it will travel, which Region it is to be emitted from, etc.
PhRect -- t *rects The "PhRect -- t" indicates that this is a "Photon Rectangle Type" and that "*rects" points to an array of rectangles. The "event" struct passed as the first parameter contains an element which declares the number of rectangles in this array.
void *data The "void" indicates that this data is of no specific type and that "*data" points to it. The length of the data is specified by an element in the Event structure passed as the first parameter.
3.) PhEventNext--Provide synchronous Event notification
This API call allows an application to stop and wait for an Event to intersect a Region owned by the application. Other calls exist m allow the application to check for an Event without stopping, and to cause the present invention to asynchronously notify the application if an Event is pending. The declaration for this interface function takes the form:
______________________________________int PhEventNext( void *buffer, unsigned size );______________________________________
This indicates that the function returns a data type of "int" or integer, indicating success or failure of this call. The two parameters are:
void *buffer. The "void" indicates that the "*buffer" points to a place in memory where data of an unspecified type will be stored when the Event arrives.
unsigned size The "unsigned" indicates that this parameter is an unsigned integer, "size" indicate the size of the buffer available to store the Event received by this API call.
Example Sequence of Operation
The following text describes the operation of the present invention for the following sequence of Events:
1.) An application uses the PhRegionOpen API call to open a Region in th present invention's Event Space.
2.) The application then emits a draw Event from this Region into the Event Space.
3.) An application acting as a graphics driver receives the draw Event (using the PhEventNext API call) and renders it to the screen.
Refer to Program: "Opening a Region" below for a sample program that uses this API call.
The program starts within main() by attaching to the present invention's microkernel and then calls the open region function.
The open -- region function declares some structures and initializes them with the values needed to define the Region to be created. The Region being defined is declared to be Sensitive to pointer motion and mouse button release Events. It is also setup to be Opaque to all pointer Events, draw Events and expose Events. The origin (top, left corner) of the Region is set to (100,100) and the rectangle structure defining the Region size is set to describe a Region spanning from (100,100) to (300,300).
Now that the structures defining the Region to be created are complete, the PhRegionOpen API call is issued, passing it these structures. The first parameter of this API call is set to indicate which elements in the structure have been initialized, so that the present invention will know which remaining elements should be set to default values.
PhRegionOpen API call will place the passed parameters into a message and use the underlying inter-process communication (IPC) services of the operating system (OS) to pass the request to the present invention's microkernel.
The present invention's microkernel will receive the request (84) and begin processing (see "Main Processing Loop" flow chart, FIG. 26).
Upon inspection (86), the present invention will recognize that this is a Region request and call the function which handles Regions (88) (see "Region Processing" flow chart, FIG. 27). That function will recognize (90) that a Region open request was received and call a function (92) to inform this operation. (FIGS. 29 and 30 illustrate flow charts for the Close Region and Change Region functions of the Region Processing flow chart,)
The open Region function (see "Open Region" flow chart, FIG. 28) will allocate memory for a draw Region structure (94) and then inspect the first parameter passed rate this API call. Using the bits set in this field, the open -- Region function will know which elements in the second parameter are set to application specified values, and which should be set to defaults. The elements within the structure will be modified accordingly (96).
If upon inspection (98) some data is found to be attached to this Region, memory will be allocated for the data, the data copied into the allocated memory, and this memory will be attached to the previously allocated Region structure (100).
If upon insertion (102) Region Brother is found to be specified, the present invention's microkernel will locale the specified Region and attach the newly created Region appropriately (104).
Once the Region processing within the present invention's microkernel is complete, the application program continues processing. In this case, the application proceeds to draw a black rectangle covering the rectangle just placed into the present invention's Event Space. It does this by calling PtSetRegion to specify which Region to draw the rectangle from, calling PgSetDrawColor to specify a colour (in this example, black) and PgDrawFillRect to actually draw the black, filled rectangle.
The draw calls just executed actually result in a series of draw command codes being deposited into a buffer within the application's private memory space. When the application calls PgFlush(), this draw buffer is passed to the present invention's microkernel. The PgFlush() API routine actually uses a variant of the PhEventEmit API call to pass this draw buffer to the microkernel, instructing the present invention to emit the draw buffer as an draw Event travelling away from the Region in the Event Space towards the user (away from the root plane).
When the present invention receives the draw Event (see the "Main Processing Loop" flow chart, FIG. 26) it examines it to determine what type of request it represents (106), and then calls the Event Processing function (108) in the microkernel (see the "Event Processing" flow chart, FIG. 31 A-B).
The Event processing function first locates an Event entry within the pool of Event entries that is not currently in use (110) and then copies. The received draw Event into this Event entry (112).
The link count on this entry is incremented (114), causing it to be set from zero (not in use) to one (in use in one place within the present invention's microkernel, the Event processing routine).
The absolute coordinate bit within the Event entry is examined (116) to determine if the coordinates of the data within the Event need to be translated from Region-relative coordinates to the present invention's absolute coordinates.
If the coordinates ate: not already expressed in absolute terms, then the Event processing function will adjust the Event origin coordinates (118) from the Region-relative form the application originally supplied to absolute coordinates within the present invention's Event Space. The rectangle set associated with the Event will also be translated (120) from Region-relative coordinates to absolute coordinates if necessary.
The intersection of the Event's rectangle set and the originating Region will be computed (122). This ensures that the Event being emitted is properly constrained to the boundary of the originating Region.
If upon examination (124) the inclusive bit is set in the Event entry, then the current -- Region will be set equal to the Region the Event is being emitted from (126). If not, then the current -- Region will be set to the Region in front of the originating Region (128) when the Event direction is found 130) to be towards the user (away from the root plane), or set to the Region behind the originating Region (132) when the Event direction is towards to root plane (see FIG. 3B for the continuation of the Event Processing flow chart)
If the Event's rectangle set describes a non-zero area (134), and the Event's current -- Region is still between the root plane and the user as determined at (136), the following processing will be done:
The Event's rectangle set is set to the intersection of the current Region and the Event's rectangle set (138).
If upon examination (140) the current -- Region is found to be Opaque to the Event type (a draw Event in this case), then the current -- Region's rectangle set is "clipped" from the Event's rectangle set (142). This behaviour has the effect of overlapping application Regions (or windows) preventing draw Events from underlying Regions overwriting the from-most windows. The draw Event (of which the rectangle set is a component) has been modified to reflect it's intersection with the Opaque Region.
If upon examination (144) the current -- Region is found to be Sensitive to the Event type (a draw Event in this case), then the present invention will queue a copy (146) of the draw Event (including its rectangle set) to be sent to the application process which owns the Region. The link count in the Event entry is incremented to reflect that the Event entry is in use in more than one place in the present invention's microkernel. For this example, we will assume that a graphics driver application is present in the system, and that it has placed a Region Sensitive to draw Events in front of the application. As a result, a copy of the draw Event will he queued to go to the graphics driver (which is nothing more than an application program's Region Sensitive to draw Events). The link count will be two because the Event entry is in use by both the Event processing function and the Event queue.
Since the direction of travel for the draw Event is towards the user (148), the current -- Region will be set to the Region in front of the Region just processed (150). Had the direction been found (148) towards the root plane, then the current -- Region would have been set to the Region behind the current -- Region (152).
This is the end of the while loop started above.
At this point, the draw Event would have either had it's rectangle set reduced such that it covered zero area (essentially, the Region of origin for the draw Event is completely hidden by Opaque Regions) or had passed outside of the root-plane-to-user span of the Event Space. The link count of the Event entry would have been decremented, and if the count went to zero, the Event entry would be free for re-use by another Event. Since our example resulted in the draw Event also being queued to a graphics driver application, the link count would have been decremented from two to one, and therefore not released from memory.
The present invention's microkernel will dequeue the draw Event to the graphics driver application that owned the Region Sensitive to draw Events, and the link count will again be decremented. Having been decremented to zero, the Event entry would be free for re-use.
The graphics driver would be waiting for an Event from the present invention's microkernel because of having used the PhEventNext API call (or a variant). When the present invention dequeued the draw Event, this would cause the draw Event to be passed to the graphics driver application (using the underlying OS's IPC services) and the graphics driver application would begin processing the draw Event.
A graphics driver application for the present invention is nothing more complicated than a program which knows how to examine the draw Event and render onto the display the individual draw requests contained within the draw Event. For this example, the draw request would result in a black rectangle being drawn to the screen at the coordinates that corresponded to the position of the original application's position in the present invention's Event Space (100,100).
Program; Opening a Region
This example opens an Opaque Region, with the root Region as its Parent. The program senses any pointer motion Events that pass through its Region and draws a rectangle at the current pointer position. If the user clicks in the Region, the program terminates.
__________________________________________________________________________ #include <stdio.h> #include <stdlib.h> #include <Ph.h> PhRid.sub.-- t open.sub.-- region( void ) { PhRegion.sub.-- t region; PhRect.sub.-- t rect; PhRid.sub.-- t rid; /* Wish to have pointer motion events enqueued to us */ memset (&region, 0, sizeof (PhRegion.sub.-- t)); region.events.sub.-- sense = Ph.sub.-- EV.sub.-- PTR.sub.-- MOTION| Ph.sub.-- EV.sub.-- BUT.sub.-- RELEASE; /* Wish to be opaque to all pointer-type events and be visually opaque */ region.events.sub.-- opaque = Ph.sub.-- EV.sub.-- PTR.sub.-- ALL| Ph.sub.-- EV.sub.-- DRAW | Ph.sub.-- EV.sub.-- EXPOSE; /* Origin at (100,100) relative to root */ region.origin.x = region.origin.y = 100; /* Open region from (absolute) (100,100) to (300,300) */ rect.ul.x = rect.ul.y = 0; rect.lr.x = rect.lr.y = 200; rid = PhRegionOpen( Ph.sub.-- REGION.sub.-- EV.sub.-- SENSE | Ph.sub.-- REGION.sub.-- EV.sub.-- OPAQUE | Ph.sub.-- REGION.sub.-- ORIGIN | Ph.sub.-- REGION.sub.-- RECT, &region, &rect, NULL); if( |rid ) { fprintf( stderr, "Couldn't open region\n" ); exit( EXIT.sub.-- FAILURE ); } /* black out the region */ PgSetRegion( rid ); PgSetDrawColor( Pg.sub.-- BLACK ); PgDrawFillRect( &rect ); PgFlush(); return( rid ); void draw.sub.-- at.sub.-- cursor( PhPoint.sub.-- t *pos ){ PhRect.sub.-- t rect; static int count = 0; PgColor.sub.-- t color; rect.ul.x = pos->>x - 10; rect.ul.y = pos->>y - 10; rect.lr.x = pos->>x + 10; rect.lr.y = pos->>y + 10; switch( count % 3 ) { case 0; PgsetDrawColor( Pg.sub.-- RED ); break; case 1: PgSetDrawColor( Pg.sub.-- GREEN ); break; default: PgSetDrawColor( Pg.sub.-- BLUE ); } PgDrawFillRect( &rect ); PgFlush();}main( int argc, char *argv !){ PhEvent.sub.-- t *event; int go = 1; if( NULL == PhAttach( NULL, NULL ) ) { fprintf( stderr, "Couldn't attach a Photon channel.\n" ); exit( EXIT.sub.-- FAILURE ); } if( -1 == open.sub.-- region() ) { fprintf( stderr, "Couldn't open region.\n" ); exit( EXIT.sub.-- FAILURE); } if( NULL == (event = malloc( sizeof( PhEvent.sub.-- t) + 1000) ) ){ fprintf( stderr, "Couldn't allocate event buffer.\n" ); exit( EXIT.sub.-- FAILURE ); } while( go ) { if( PhEventNext( event, sizeof(PhEvent.sub.-- t ) + 1000) == Ph.sub.-- EVENT.sub.-- MSG ) { if( event->>type == Ph.sub.-- EV.sub.-- PTR MOTION ) draw.sub.-- at.sub.-- cursor( (PhPoint.sub.-- t *)PhGetRects( event) ); elsego = 0; } else fprintf( stderr, "Error.\n" ); } }__________________________________________________________________________
Numerous modifications, variations and alterations can be made to the particular embodiments disclosed without departing from the scope of the invention which is defined by the claims. | A system for managing the interaction of programs is provided, comprising means for storing a set of predetermined characteristics respecting each program to be managed, each set of characteristics including an input signal type characteristic indicative of the identity of the type of inputs signals to which the program associated with the set of characteristics is responsive and a signal modification characteristic indicative of whether a type of input signal is to be modified by the associated program; means responsive to input signals having predetermined properties emitted from one of the programs for interrogating each set of predetermined characteristics in a predetermined sequence, determining whether the associated program is responsive to a current input signal, determining whether the properties of the current input signal are to be modified and, if so, modifying the properties of the input signal; and means for emitting an output signal to the programs determined to be responsive to the input signal. | 6 |
RELATED APPLICATIONS
[0001] This application claims the benefit of co-pending U.S. Provisional Patent Application Ser. No. 61/397,093, filed 7 Jun. 2010.
BACKGROUND OF THE INVENTION
[0002] The present invention related to disposable undergarments and more particularly, a pants type undergarment which is equipped with refastenable side seams.
[0003] Disposable undergarments of the children's training pant type, or of the adult incontinence type, are generally made up of two nonwoven layers of material with elastic strands of material placed between the two nonwoven layers of material thus creating an elastic web laminate.
SUMMARY OF THE INVENTION
[0004] The present invention discloses methods of forming a pants type diaper with refastenable side seams. A pants type disposable undergarment is provided which is equipped with a pre-fastened pull-on pant with a side lap seam formed by the methods of the present invention. Top and bottom portions of a side panel assembly are folded over a stretch portion of the side panel, and both the top and bottom portions are bonded to the stretch portion of the side panel, at first temporary bond points and at second ultrasonic or mechanical bond portions. The second ultrasonic or mechanical bond portions are overlain with a hook-type fastener for later bonding with the first temporary bond points, to form a lap seam at the left and right sides of the waist of a wearer. A folded product is produced that is pre-fastened in this manner, but the bond between the hook-type fastener and the first temporary bonded portion can be released and re-fastened if desired.
[0005] A product and method to produce a resealable pant such that the front and rear waist side panel regions can be easily engaged with one another.
[0006] A method to produce a resealable pant in such a manner so that the front and rear waist side panels are a single piece during manufacturing is disclosed. A hinged panel with a resealable fastener to align with the mating side panel when folded to form a lap seam is also disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a perspective view of an undergarment produced according to the present invention.
[0008] FIG. 2 is a top planar view of a composite of material used to form a side panel.
[0009] FIG. 3 is a top planar view of a side panel assembly of embodiment shown in FIG. 2 , with the top and bottom non-stretch materials folded over.
[0010] FIG. 4 is a top planar view of assembly of embodiment shown in FIG. 3 , with the top and bottom non-stretch materials folded over and bonded in portions to the stretch portions.
[0011] FIG. 5 is a top planar view of assembly of embodiment shown in FIG. 4 , with the top and bottom non-stretch materials folded over and bonded in portions to the stretch portions, and a hook material applied to the back side panel proximate to the bond area.
[0012] FIG. 6 is a top planar view of assembly of embodiment shown in FIG. 5 , with the top and bottom non-stretch materials folded over and bonded in portions to the stretch portions, and a hook material applied to the back side panel proximate to the bond area, with portions of the assembly removed by die cut to facilitate shaping of the side panel.
[0013] FIG. 7 is a top planar view of assembly of embodiment shown in FIG. 6 , with the top and bottom non-stretch materials folded over and bonded in portions to the stretch portions, and a hook material applied to the back side panel proximate to the bond area, with portions of the assembly removed by die cut to facilitate shaping of the side panel, and the side panel slit and spread apart.
[0014] FIG. 8 is a top planar view of assembly of embodiment shown in FIG. 7 , with the top and bottom non-stretch materials folded over and bonded in portions to the stretch portions, and a hook material applied to the back side panel proximate to the bond area, with portions of the assembly removed by die cut to facilitate shaping of the side panel, and the side panel slit and spread apart, bonded to a top sheet material.
[0015] FIG. 9 is a top planar view of assembly of embodiment shown in FIG. 8 , with the top and bottom non-stretch materials folded over and bonded in portions to the stretch portions, and a hook material applied to the back side panel proximate to the bond area, with portions of the assembly removed by die cut to facilitate shaping of the side panel, and the side panel slit and spread apart, bonded to a top sheet material, and this combination combined with a core and back sheet material.
[0016] FIG. 10 is a top planar view of assembly of embodiment shown in FIG. 9 , with the top and bottom non-stretch materials folded over and bonded in portions to the stretch portions, and a hook material applied to the back side panel proximate to the bond area, with portions of the assembly removed by die cut to facilitate shaping of the side panel, and the side panel slit and spread apart, bonded to a top sheet material, and this combination combined with a core and back sheet material, showing the finished product prior to folding.
[0017] FIG. 11 is a finished product after folding, and prior to packaging.
[0018] FIG. 12 is an exploded cross sectional view of the pre-fastened pull-on pant with a side lap seam formed by the methods of the present invention.
[0019] FIG. 13 is schematic representation of formation of an alternate embodiment of the present invention, disclosed is a nonwoven tab process with a continuous hook formation, with the hooks away from the body.
[0020] FIG. 14 is a schematic representation of formation of an alternate embodiment of the present invention, disclosed is a nonwoven tab process with a discrete hook formation, with the hooks away from the body.
[0021] FIG. 15 is a schematic representation of formation of an alternate embodiment of the present invention, disclosed is a nonwoven tab process with a discrete hook formation extending into a die cut region, with the hooks away from the body.
[0022] FIG. 16 is a schematic representation of formation of an alternate embodiment of the present invention, disclosed is a nonwoven tab process with a discrete hook overlapping cut formation, with the hooks away from the body.
[0023] FIG. 17 is a schematic representation of formation of an alternate embodiment of the present invention, disclosed is a nonwoven tab process with a multiple discrete hook overlapping cut formation, with the hooks away from the body.
[0024] FIG. 18 is a schematic representation of formation of an alternate embodiment of the present invention, disclosed is a nonwoven tab process with hooks on the front side panel, with the hooks away from the body.
[0025] FIG. 19 is a schematic representation of formation of an alternate embodiment of the present invention, disclosed is a nonwoven tab process with hooks on the front side panel, and nonwoven tabs on the back panel, with hooks toward the body.
[0026] FIG. 20 is a schematic representation of formation of an alternate embodiment of the present invention, disclosed is a nonwoven tab process with hooks on the rear or back side panel, and nonwoven tabs on the front panel, with hooks toward the body.
[0027] FIG. 21 is a plan view of a product produced according to the present invention.
[0028] FIGS. 22-24 are cross sectional views of a product produced according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.
[0030] Referring to the Figures generally, two adjacent products are shown constructed next to one another because the products 10 are preferably constructed on a continuous processing system for later separation to form individual diaper products (see, e.g., FIG. 9 prior to separation to form individual products in FIG. 10 ).
[0031] FIG. 1 is a perspective view of an undergarment 10 produced according to the present invention.
[0032] Referring now to FIG. 2 a top planar view of a composite of material used to form a side panel is shown. First and second segments of material 22 are provided at the top and bottom of the composite, along with first and second segments of preferably stretchy material 20 . The first and second segments of material 22 can be formed of the same piece of stretch material 20 , or formed separately of stretch or non-stretch material and then bonded to the stretch material 20 . A segment of non-stretch material 24 is provided between the first and second segments 20 as shown.
[0033] Referring now to FIG. 3 , the first and second segments of material 22 are folded either over or under the adjoining first and second segments of stretch material 22 . This can be done with a folding machine known in the art.
[0034] As shown in FIG. 4 a top planar view of assembly of embodiment shown in FIG. 3 is shown, with the top and bottom segments of material 22 folded over. The top and bottom segments of material 22 are then conceptually divided into segments 22 a and 22 b , both at the top and the bottom of the composite, alternating continuously in what will eventually become physically divided portions which will be the front left (top 22 a L), front right (bottom 22 a R) and the back left (top 22 b L) and back right (bottom 22 b R) side panel portions.
[0035] In areas 22 a R and 22 a L (front left and right side panel portions), the folded segments of material 22 are temporarily bonded to the underlying (or overlying) layer(s) of stretch material 20 . The temporary bonding can be done for instance at spaced apart tack bond sites. The purpose of the temporary bond is to provide control of the material throughout the high-speed manufacturing process, but to allow the bond to become detached when the lap seam is eventually formed, and worn about the waist of a user.
[0036] In areas 22 b R and 22 b L (rear left and right side panel portions), the folded segments of material 22 are ultrasonically or mechanically bonded to the underlying (or overlying) layer(s) of stretch material 20 in zones 26 . The bonding can be done in other ways, such as adhesively.
[0037] Following this step, and referring now to FIG. 5 , after the top and bottom materials 22 have been folded over and bonded in portions to the stretch portions 20 as previously described, a material 28 is applied to the back side panel in areas 22 b L and 22 b R proximate to and preferably overlying at least in part the bond areas 26 suitable for later attachment to the tack-bonded portions 22 . Preferably, the material 28 is a hook type material suitable for attachment to loose loop type material if used for portions 22 .
[0038] Referring now to FIG. 6 , the next step in the process is to die cut areas 30 from side panel assembly which can be discarded or preferably recycled. Preferably, portions 30 of the side panel assembly are removed by die cut or other means to facilitate shaping of the side panel to conform with the waist or leg openings of the diaper configuration, shaped to conform to the body of the wearer.
[0039] Next, as shown in FIG. 7 , the side panel assemblies are slit, preferably in the middle of the non-stretch panel 24 , and spread apart to increase the distance between the left side panels ( 22 a L and 22 b L) and the right side panels ( 22 a R and 22 a L) panels to form left and right intermediate assemblies. Next, the front panel ( 22 a L and 22 a R) assemblies are separated from the 22 b L rear panel assemblies ( 22 b L and 22 b R) panels, for instance by slitting and slip cutting methods (not shown) for deployment onto a continuous top sheet web 30 in the positions as shown in FIG. 8 .
[0040] As shown on FIG. 8 , the non-stretch panel 24 portions of the side panel assemblies are introduced to the top sheet assembly 12 in overlapping fashion, and bonded thereto in the portions of an overlap between the non-stretch panel 24 and top sheet assembly area identified as overlap area 32 .
[0041] Referring to FIGS. 9 and 12 (showing the product cross-section after folding), after slitting the side panel assembly to form independent left ( 22 a L and 22 b L) and right ( 22 a R and 22 b R) panels, the left panels are further subdivided to form the left front ( 22 a L) and left rear ( 22 b L) panels, and to form the right front ( 22 a R) and right rear ( 22 b R) panels, and introduced to the back sheet material 30 . At this point, as shown in FIG. 9 , additional components of the diaper panel can be introduced either independently or in pre-constructed fashion. Included are the cuff non-woven 46 containing cuff elastics 44 , leg elastics 34 , the inner non-woven 38 , the absorbent core 36 captured by tissue, the acquisition layer 47 , poly layer 40 , inner non-woven 38 , and waist band 48 .
[0042] Referring now to FIG. 10 , two adjacent products can be separated from one another, for instance, by die cutting, to form independent products 10 . is a top planar view of assembly of embodiment shown in FIG. 9 , with the top and bottom non-stretch materials folded over and bonded in portions to the stretch portions, and a hook material applied to the back side panel proximate to the bond area, with portions of the assembly removed by die cut to facilitate shaping of the side panel, and the side panel slit and spread apart, bonded to a top sheet material, and this combination combined with a core and back sheet material, showing the finished product prior to folding.
[0043] Referring now to FIG. 11 , the diaper product is folded generally at its midsection to form a folded product, with the material 28 being urged against the material 22 , to form the refastenable pre-fastened product. In this fashion, the hook material 28 contained on side panel portion 22 b L is joined with the side panel portion 22 a L, and the hook material 28 contained on side panel portion 22 b R is joined with the side panel portion 22 a R. This joinder is done by pressure during the folding process, such that the finished product after folding will have pre-sealed sides. If the user desires, the hook material 28 can then be separated from the side panel portions 22 a L and 22 a R for taking the garment off the user if the product is insulted, or can be opened and re-sealed if the product is still clean.
[0044] Referring now to FIG. 13 , a schematic representation of formation of an alternate embodiment of the present invention is shown, disclosed is a nonwoven tab process with a continuous hook 28 formation, with the hooks 28 away from the body. The formation of this product is much the same as previously described. Working from left to right on FIG. 13 , in sequential fashion, non-woven tab material 22 is folded over at the top and the bottom and tack bonded. Next, hook material 28 is coupled to the tack bonded material 22 , slit and spread. Next, this composite is introduced to side panel material 20 . Die cut areas 30 are removed from the side panel assembly. At this point in the procedure, the construction process resumes at the point previously described with reference to FIGS. 6-11 . To recap, the left and right and front and back panels are slit and separated, as shown in FIG. 7 , bonded to the incoming chassis web ( FIGS. 8 , 9 ), severed into individual diapers ( FIG. 10 ) and folded ( FIG. 11 ) prior to packaging.
[0045] Referring now to FIG. 14 , a schematic representation of formation of an alternate embodiment of the present invention is shown. In this embodiment, the hook material 28 is applied to tack bonded material 22 discretely (as opposed to continuously, as shown on FIG. 13 ). Discrete application of the hook material 28 can be performed, for instanced by slip/cut techniques. In this embodiment, the discrete hook material 28 is not severed, instead the combination tab 20 /hook 28 material is severed in between hook 28 portions.
[0046] Referring now to FIG. 15 , an alternate embodiment of the present invention is shown, in which a nonwoven tab created of material 20 (longer than the hook material 28 segments) extend into the die cut region 30 such that in use the material 20 would extend nearly the length of the back side panel 20 .
[0047] Referring now to FIG. 16 , an alternate embodiment is shown, with a discrete hook 28 overlapping the die-cut formation, with the hooks away from the body. In this embodiment, the hook material is introduced such that the hook material 28 overlaps the space where the material is cut prior to introduction onto the side panel. The result is that the hook material 28 resides on the back side panel in two discrete pieces. The same result is achieved if, as shown in FIG. 17 , multiple discrete hook portions 28 are applied to the nonwoven tab 20 material, slit and separated prior to introduction onto the side panels 22 .
[0048] Referring now to FIG. 18 , an alternate embodiment of the present invention is shown with nonwoven tab process with hooks 28 on the front side panel, with the hooks 28 facing away from the body.
[0049] Referring now to FIG. 19 an alternate embodiment of the present invention is shown, with hooks 28 on the front side panel, and the folded over nonwoven 22 on the back panel, with hooks 28 toward the body. FIG. 20 is similar, except that the folded over nonwoven 22 is on the front panel, and the hooks 28 are on the back panel.
[0050] Referring now to FIG. 21 is a plan view of a product produced according to the present invention, is shown, with a back side panel cross section shown in FIG. 22 , a front side panel construction shown in FIG. 23 , and a lap-seam full product cross section shown in FIG. 24 . Referring to FIG. 22 showing the back panel cross section, undergarment 10 is formed with top sheet 12 , back sheet 14 , bonded where desired with adhesive 16 or ultrasonic bonds 18 , or tack bonds 19 . A poly layer 40 is provided, as are leg elastics 34 , panels 20 , absorbent core 35 carried by core wrap 37 (preferably non-woven), top tissue 50 , acquisition layer 47 , and cuff elastics 44 carried by cuff non-woven 46 .
[0051] Referring to FIG. 23 showing the front panel cross section, the top sheet 12 is coupled to the cuff 46 , and the acquisition layer 47 , the top tissue 50 , and next the ftong panels about the core 36 carried by the core wrap 37 . Leg elastics 34 are provided, and completing the cross section is poly 40 coupled to the back sheet 14 .
[0052] FIG. 24 shows the lap seam (overlap) provided by the hook material 38 , releasably coupled about the waist of a user with material 22 .
[0053] The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiments have been described, the details may be changed without departing from the invention, which is defined by the claims. | A pants type disposable undergarment is provided which is equipped with a pre-fastened pull-on pant with a side lap seam formed by the methods of the present invention, and methods for producing such disposable undergarments. | 8 |
This application claims the benefit of U.S. provisional patent application Ser. No. 60/959,093 filed on Jul. 11, 2007.
FIELD OF THE INVENTION
The invention relates to systems for lifting a concrete forming structure or apparatus.
BACKGROUND
Hydraulically lifted concrete form systems for elevator cores are presently known and used on building construction sites. In leveling these hydraulically lifted concrete forms from floor to floor, several systems are presently used, and they each have significant drawbacks.
The first known raising system utilizes water levels. The problems with water levels are that they must be maintained and serviced prior to every lift to be sure they are operational. The accuracy of the lift is determined by the operator of the system. The accuracy of how even the form is lifted is dependent on how quickly the water levels respond in the tubes and how quickly the operator responds to variances. Often times the operator will ignore or not be aware of variances that can be critical to the loading of major form components creating an unsafe condition.
The water lines used in a water leveling system can often become kinked and/or clogged causing the readings to be incorrect. During winter conditions, precautions have to be taken to be sure that the water or other liquid in the lines does not freeze. In summer conditions, the water or other liquid in the lines can evaporate, requiring the operator to top off the liquid prior to starting. Because of the length of the water lines and the routing that often times must be taken, the lines are prone to damage. All these factors contribute to inaccuracy in the lifting process. Frequently the water levels are ignored, and the concrete form is lifted with no leveling assistance.
A second type of system used to coordinate lifting the system involves having men located at each of the critical lifting points to physically measure the progress of the lift from the previous pour as it progresses. The progress is often shouted out to the operator or communicated via radio. The operator analyzes what each of the measurements mean and turns the power units on or off accordingly. The system is very labor intensive and inaccurate requiring many men to measure at once and is only as accurate as the men doing the physical measurement and the ability of the operator to analyze the information and respond quickly to it.
A third method depends on the operator's ability to sense that the concrete form is rising. In this method, the operator uses reference structures that are close by to coordinate the rise of the system. This method is the most inaccurate since no actual measuring devices are used.
A fourth method depends on the repeatability of mechanical pump valves or sensors. This method operates on the theory that if all cylinders are pumped an equal volume, they will all ascend equally. This is often not true because the equipment used cannot guarantee repeatability. For instance, there may be leakage in the system or there may be variances in the construction of the items employed in the lift. The number of hydraulic cylinders coordinated at once is limited.
Monitoring the system in order to achieve the desired lift height on all four systems depends on a physical measurement by the operator or a helper of the operator.
The present inventors recognize a need for a form control and monitoring system that coordinates all hydraulic cylinders quickly, safely and precisely.
SUMMARY OF THE INVENTION
The invention provides a form control and monitoring system that coordinates the raising of form elements by lift apparatus so that the form elements are lifted in a closely controlled, automatic manner. The lift apparatus includes plural lifting devices wherein the extent of lifting at each device is closely controlled with respect to the other lifting devices. This close control can be used to ensure a precise, even lifting of the entire lift apparatus. The control and monitoring system of the invention particularly enhances hydraulically lifted concrete form systems such as used for elevator cores.
The invention includes one or more form elements for defining an area to receive a formable material, such as concrete. According to one embodiment, each element is attached to the form structure. A lift apparatus is provided for lifting the form elements. The lift apparatus comprises a measurement device for measuring the position of the lift apparatus relative to a fixed point. The lift apparatus is connected to the form structure. A control unit is provided for controlling the lift apparatus. The control unit is signal connected to the measurement device and is signal connected to the lift apparatus.
In one embodiment, the lift apparatus comprises a plurality of jack assemblies connected to the form structure. The jack assemblies are connectable to a formed object, such as a previously formed concrete structure, or a base. Each jack assembly comprises an actuator, such as for example a hydraulic cylinder for raising the form elements along with the form structure.
In another embodiment, the measurement device comprises a plurality of sensors. Each sensor is connected to each jack assembly for measuring a distance that the actuator moves the form structure.
In another embodiment, the control unit comprises deviation calculating instructions for calculating a deviation defined by a difference between a position of each jack as reported by the corresponding sensor. The control until continuously computes the deviation while the control unit is in a lifting mode. The control unit comprises deviation comparison instructions for comparing the deviation to a predefined deviation tolerance range. The control unit comprises pausing instructions for stopping a respective one or more of the jacks when the sensor corresponding to the jacks provides a position value that is outside of the deviation tolerance range.
In another embodiment, the control unit comprises pausing instructions for pausing one jack while the sensor corresponding to the jack reports a position value that is outside of a deviation tolerance range and above the position values of the non-paused jacks. Also the control unit may comprise pausing instructions for pausing all other jacks while the sensor corresponding the non-paused jack reports a position value that is outside of a deviation tolerance range and below the position values of the paused jacks.
The control unit may comprise completion detecting instructions for signaling one or more of the jacks to stop when the jack has reached the pre-defined or a user defined lift distance or final lift height.
After the lift is complete the form elements or panels can be anchored to the previously formed object, for example concrete. The jacks then may be disconnected from the formed object and retracted back to their starting position.
Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, and from the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an overview drawing (with many components removed) of an exemplary construction site depicting the wireless signals and a representative plan view of the present invention;
FIG. 1A is a detailed view of an exemplary construction site depicting a plan view of the present invention;
FIG. 2 is a side elevational view of the form lift of the present invention taken along the line 1 A- 1 A in FIG. 1A showing the form lift in an initial position;
FIG. 3 is a detail view of a jack assembly of the present invention, showing its components and other components of the system;
FIGS. 4A-4B are flow diagrams illustrating the process employed by a control panel during the lift of the form in an embodiment of the invention;
FIG. 5 is a side elevational view of the form lift of the present invention, similar to the view of FIG. 2 , showing the form lift in an intermediate position;
FIG. 6 is a side elevational view of the form lift of the present invention, similar to the view of FIG. 2 , showing the form lift in a final lift position;
FIG. 7 is an exemplary central control panel, power panel and a lifting power unit arrangement;
FIG. 8 is a side schematic view of a vertical alignment verification system with elements of the jack assembly removed for clarity; and
FIG. 9 is a bottom view of a vertical alignment target of the vertical alignment verification system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 , 1 A and 2 , a self-raising form control system 30 of the present invention is illustrated in an initial set up position. Referring specifically to FIG. 2 , it can be seen that the concrete for levels A through C have been poured and formed and that the form control system 30 has been put in place prior to extending the form for the next level (Level D). Deck levels 11 have been put in place on each level between the formed concrete. Outside hanging scaffolding 9 , 12 has also been put in place to give personnel access to the concrete form assembly. The form control system 30 , in this embodiment, includes a central control panel 13 , a power control panel 14 , a grid support beam 1 and a number of jack assemblies 32 . In this embodiment, the form control system 30 includes six jack assemblies 32 , as shown in FIG. 1A , which are attached to the grid support beam 1 .
As shown in FIG. 2 , the central control panel 13 and the power control panel 14 are connected to the grid support beam 1 . A number of fixed concrete form panels 3 and movable or rolling concrete form panels 2 are also connected to the grid support beam 1 . In the figures depicting this embodiment, the central control panel 13 and the power control panel 14 are shown as separate units. However, it should be understood that the central control panel 13 and the power control panel 14 can be built integrated with one another. The control panel 13 and the power control panel 14 maybe integrated into a control unit.
In one embodiment, the control unit may be a computer and the control unit may comprise one or more electronic processor chips, programmable logic controllers, logic processors, memory circuits, RAMs, ROMs, electronic chips, and or microprocessors. In one embodiment, the functions and or operations carried out by the control unit can be in the form of machine readable instructions. In one embodiment, the machine readable instructions may, for example, comprise one or more gates of a circuit, instructions hardcoded into a circuit, or programmable instructions, as for example software code, executed by a processor or circuit capable of reading those instructions.
Also, referring to FIG. 3 , the central control panel 13 , in one embodiment, includes a transceiver 17 and a power line 19 . The power line 19 is connected to the power control panel 14 .
In this embodiment, referring specifically to FIG. 3 , each jack assembly 32 includes a jack support bracket 6 , a target 8 , a position sensor 7 , an actuator 5 , a lifting power unit 4 , a pendant switch 20 and electric and hydraulic lines 15 , 16 . The actuator 5 may comprise, for example, a hydraulic cylinder, a pneumatic cylinder, or a servo motor. To put the form control system 30 in place, each jack assembly 32 is connected to the concrete wall 21 on the level previously formed by using concrete inserts 22 to attach the jack support brackets 6 for each jack assembly 32 to the concrete wall 21 . The actuators 5 of each jack assembly 32 are connected to and support the grid support beam 1 . In the initial set up position depicted in FIG. 2 , the actuators 5 of each jack assembly 32 are all at the same starting height.
With the system 30 in the initial set up position, the system 30 is ready for operation. The process as described below and shown in FIGS. 4A and 4B may be carried out by the control unit in communication with the component parts, such as the jack assemblies 32 , and with optional input from a user. At the start of the process, the system operator confirms that the actuators 5 are in fact all at the same level. If they are not, the operator manually adjusts the actuators 5 so they are at the same level.
Referring now to FIG. 4 , the system operator at step 40 initiates the system. Then at step 42 , the operator enters the lift height he wishes to raise the grid support beam 1 , and this parameter is stored as a lift distance value. In an alternative embodiment, the lift distance value may be pre-programmed. The lift height or distance is the absolute distance the actuators 5 have to travel in this phase of the construction. After the lift height is entered, the operator starts the lift sequence and the actuators 5 begin to lift the grid support beam 1 as indicated at step 44 . In one embodiment of the invention, the operator does this by pressing an “Automatic” and “Start” button on the central control panel 13 . As the actuators 5 move upward, the position sensor 7 of each jack assembly 32 sends a signal downward towards the corresponding target 8 on the jack assembly 32 . The jack assembly 32 captures the distance traveled by the signal between the position sensor 7 and the target 8 and uses this to determine the distance that the actuator 5 has moved or the distance the actuator 5 has moved the concrete form panels, which may be represented as a position value. The distance traveled by each actuator 5 is continually captured and transmitted from the position sensor of the jack assembly 32 to the transceiver 17 of the central control panel 13 , as indicated at step 46 and by the signal lines 18 ( FIGS. 1 , 1 A and 3 ). In one embodiment, the distance the actuator 5 has traveled is communicated from the jack assembly 32 to the transceiver 17 by a PHOENIX BLUETOOTH transceiver located inside the lifting power unit 4 . In one embodiment, the position sensor 7 may be a laser positioning sensor that sends a laser signal toward a laser target 8 to determine the distance traveled by each actuator 5 .
As indicated at step 48 , as the central control panel 13 receives these continuous updates on the travel distance or position value of each actuator 5 , the central control panel 13 continuously computes the height difference between the actuators 5 . The process, as indicated at step 50 , is also retrieving a pre-defined stored height tolerance parameter or deviation tolerance range. The process executed by the central control panel 13 then, at step 52 , compares the computed height differential between the actuators 5 to the retrieved tolerance parameter or deviation tolerance range. If all of the actuators 5 are within the height tolerance parameter, the process proceeds to step 54 where it determines if the actuators 5 have reached the absolute height entered by the operator at the start of the lifting operation. If the actuators 5 have reached the absolute height, then the lifting process has been completed, and the process ends as indicated at step 56 . If however at step 54 the absolute lift height has not vet been reached, then the process continues to step 58 where the system continues to lift the actuators 5 , and the process returns back to step 46 .
Referring again to step 52 , if the process had determined that the height differential between the actuators 5 was not within the height tolerance parameter, then the process proceeds to determine if the height of the evaluated actuator 5 is less than the acceptable tolerance at step 60 . If the height of the evaluated actuator 5 is less than the acceptable tolerance, then the height of the evaluated actuator 5 is too low with respect to the other actuators 5 being lifted and needs to be raised. The process then at step 62 stops the actuators 5 that are not out of tolerance, while it lifts the actuator 5 that is out of tolerance. While the process does this, it is also capturing the height of the lower actuator 5 that is being lifted at step 64 , and at step 66 , it is evaluating whether the actuator 5 being lifted is back within tolerance. If it is, then, as indicated at step 58 , the process proceeds to lift all of the actuators 5 again. If, however, the process determines at step 66 , that the actuator 5 being lifted is still not within the tolerance, the process returns to step 62 and continues to lift the lower actuator 5 . This process continues until the lower actuator 5 is brought within height differential tolerance with respect to the other actuators 5 so that it can continue to lift with the other actuators 5 .
Referring again to step 60 , if the process determines that the height of the evaluated actuator 5 is not less than the acceptable tolerance, then it must be greater than the acceptable tolerance because at step 52 it was determined that the height differential was outside of the acceptable tolerance either on the high or low side. As such, the height of the evaluated actuator 5 is too high with respect to the other actuators 5 being lifted, and the other actuators 5 need to be raised. The process proceeds to step 68 where the process stops the evaluated actuator 5 that is too high and out of tolerance, while it lifts the other actuators 5 to bring the height differential back within tolerance. While the process does this, it is also capturing the height of the higher actuator 5 with respect to the actuators 5 that are being lifted at step 70 , and at step 72 , it is evaluating whether the stopped actuator 5 is back within tolerance. If it is, then, as indicated at step 58 , the process proceeds to lift all of the actuators 5 again. If, however, the process determines at step 72 , that the stopped actuator 5 is still not within the tolerance, the process returns to step 68 and continues to lift the other actuators 5 , while holding the actuator 5 that is too high. This process continues until the actuator 5 that is too high is brought within the height differential tolerance with respect to the other actuators 5 so that it can continue to lift with the other actuators 5 .
In one embodiment, during the lift, a display monitor 34 ( FIG. 7 ) in the central control panel 13 displays bar charts representing the progress of each actuator 5 . The height that each actuator 5 has lifted is displayed next to it, as well as the number of times that it has been turned on and off during this lift. The elapsed time of the current lift and the total height of the current lift are also displayed. A logic processor monitors to see that communications are constantly kept with the position sensors 7 . If communications are lost, a fault light is lit on the central control panel 13 , and a message displayed on its monitor 34 . If the operating voltage drops below a predefined minimum voltage, such as 208 volts, as monitored by a voltage transducer in the power control panel 14 , the logic processor posts a warning message to the user, such as on the monitor, stating, for example, that the “Operating voltage has dropped below the minimum. Damage to the system may result from continued operation.”
Referring now to FIG. 5 , the hydraulic lift is illustrated in an intermediate position. At this point, the logic processor in the central control panel 13 is in control of the lift in automated mode. It is evaluating each actuator 5 , and raising them as described above to achieve an even lift to the pre-designated lift height.
Referring now to FIG. 6 , the hydraulic lift is illustrated in a final position. The final lift height that was entered at the start of the lift has been achieved. The system has shut down. Once the lift height has been achieved, the rolling concrete form panels 2 and the fixed concrete form panels 3 are re-anchored in the previous pour 21 using landing brackets 36 and are made ready for the next pour. At this point, all concrete form panels 2 , 3 are completely supported on landing brackets 36 , using concrete inserts 22 (shown in FIG. 3 ), in the previous pour. The actuators 5 that were used to raise the grid support beam 1 to the present level are unbolted from the concrete 21 at the jack support brackets 6 . The actuators 5 are retracted upward toward the grid support beam 1 for the next lift position. In one embodiment, this is accomplished by first turning the main power switch on the power control panel 14 to off and turning the switch on the central control panel 13 to manual. The lifting power unit 4 for each jack assembly 32 is also set to the manual position, and the pendant switch 20 (shown in FIG. 3 ) for each jack assembly 32 is set to the off position. The main power switch on the power control panel 14 can then be turned on. This allows each lifting power unit 4 to lift or retract its actuator 5 using the pendant switch 20 .
FIG. 8 and FIG. 9 show a vertical alignment verification system 100 of the present invention. The system 100 comprises an alignment laser 101 and an alignment target plate 103 . The target plate is preferably attached to an inside of a respective form panel 3 , near the top thereof, by a bracket 104 . In this way, the target is always pre-located at an exact position on the system 30 . The alignment laser emitter 101 is attached to the concrete wall 21 or other reference structure. When activated, the alignment laser emitter 101 projects a vertically projected visible point laser beam 101 a that effects a laser point 101 b ( FIG. 9 ) on the target plate 103 . The laser emitter 101 is self-plumbing to ensure true verticality of the laser beam 101 a . The target plate 103 contains a target 105 with a center 106 . The target plate is transparent or translucent PLEXIGLAS or the like.
A user visually inspects the target plate from above to ensure that the laser point 101 b generated by the alignment laser emitter 101 is centered on the center 106 of the target 105 to ensure the self-raising form control system 30 and the form panels 3 are in proper vertical alignment. The user may set the preferred proper vertical alignment to provide that the concrete walls 21 are formed perpendicular to the ground or perpendicular to some set horizontal reference. If a user determines that the laser is not centered on the target 106 , the user will make manual adjustments to the self-raising form control system 30 to bring the system into proper vertical alignment. In another embodiment, the vertical alignment verification system may comprise a controller and a smart target that automatically checks for proper vertical alignment and makes corresponding adjustments or alerts a user that vertical alignment is not within range.
The vertical alignment verification system 100 may comprise an alignment laser emitter and an alignment target plate pair 101 / 103 at each actuator 5 . However, having a laser emitter and an alignment target plate pair 101 / 103 on every jack may not be necessary to ensure proper vertical alignment. For a square arrangement of form panels, a minimum of three laser emitter and target plate pairs 101 / 103 is preferred to ensure proper vertical alignment for every square shaft created by the concrete walls 21 .
The alignment laser emitter 101 may be located one level below the target level. For example, in FIG. 6 , the laser emitter 101 may be located at level D when verifying vertical alignment of the self-raising form control system 30 from level D to level E. To provide greater accuracy, as available as the levels increase in elevation, the laser emitter 101 may be placed three, four, or more levels below the target level. For example, in FIG. 6 , the laser may be located at level B or level A below the target level E.
Once the actuators 5 are retracted to the next lift position, the jack assemblies 32 , through the jack support brackets 6 , are bolted to the previously poured concrete 21 for each jack assembly 32 . After all the concrete forms are poured and stripped, the system is ready to make the next lift. The concrete forms are lifted in this fashion until the total height of the structure has been reached.
While the invention has been discussed in terms of certain embodiments, it should be appreciated that the invention is not so limited. The embodiments are explained herein by way of example, and there are numerous modifications, variations and other embodiments that may be employed that would still be within the scope of the present invention. | A self-raising form control system and method is provided that that may be used to form elevator shafts and other vertical building structures. The apparatus includes one or more form elements for defining an area to receive a formable material, such as concrete. Each element is attached to the form structure. A lift apparatus is provided for lifting the form elements. The lift apparatus comprises a measurement device for measuring the position of said lift apparatus relative to a fixed point. The lift apparatus is connected to the form structure. A control unit is provided for controlling the lift apparatus. The control unit is signal connected to the measurement device and is signal connected to the lift apparatus. | 8 |
This application is a divisional of U.S. patent application Ser. No. 08/271,444, filed Jul. 7, 1994, now U.S. Pat. No. 5,607,305.
FIELD OF THE INVENTION
The present invention relates to a process for scanning, in connection with the production of a tooth, bridge or similar product usable in the human body, an outer contour of a rotating model by means of a scanning device which operates at a scanning angle, for example 45°, relative to the rotational axis of the model. The invention also relates to a device for implementing the process.
BACKGROUND OF THE INVENTION
From Swedish patent 9003967-8 (468 198), it is known to carry out a scanning or reading function on a rotating model, in which a scanning device is set at an angle (45°) relative to the rotational axis of the model. The reading is utilized by a computer for the further processing of input data and production of the product in question, which is primarily a tooth, bridge or other dental three-dimensional body.
SUMMARY OF THE INVENTION
The entire production process of formulated or desired products must be executed such that a relatively very high manufacturing accuracy is accomplished, in connection with which it may be mentioned that in many cases an accuracy of 0.01-0.05 mm is required. This places high demands upon, among other things, the capacity of the reading function to be performed with great accuracy.
The reading should be performed by the average dental technician or dentist without the need to acquire over-extensive special skills in data-processing. The invention aims to solve, these problems and proposes a tool which is easy to learn to use and implement together with normal tasks performed by the dental technician/dentist.
There is a requirement for the reading to be performed with necessary accuracy on the spot, entirely separate from the actual manufacture of the product. The dentist/dental technician should be able individually to perform a data-storage and data-transfer to the manufacturer. The invention solves this problem too.
The new tool should be operated on the basis of the principles, hitherto practiced regarding the formulation of the preparation model. The tooth preparation model should be separated from a plastic cast in a manner which is well known and then utilized in the reading function. The invention solves this problem and enables the dental technician/dentist to retain the model during its manufacture, whereby the model need not be physically sent away to a manufacturer.
The dentist or dental technician should be able to perform final adjustments to a produced crown or equivalent. The invention solves this problem by virtue of he or she being able to quickly perform, as an intermediate step, a production or manufacture of a product corresponding to the model.
The tool for the dental technician/dentist should involve the utilization of conventional data-processing equipment currently on the market and a reading function which is technically simple to handle. The invention solves this problem and proposes a specially adapted reading apparatus which is easy to handle. In addition, the utilization of a conventional personal computer for example an IBM-compatible PC of the 386 type or higher capacity) is made possible. The personal computer preferably comprises a built-in modem, by means of which read files can be transferred to the manufacturer via the public telecommunications/data network. The equipment is simple to connect.
The characteristic feature be considered of a process according to the invention is that the model is mounted in a rotary holder and is supported by the holder such that the scanned contour, above a preparation line on the model, can be exposed throughout to the angled scanning device. The process is additionally characterized in that the scanning device is directed towards a surface situated on the model below the preparation line and that the holder is activated for rotation, and the scanning device is activated for contour scanning. During the contour scanning, the scanning device and/or the holder in the vertical direction of the model.
In embodiments of the inventive concept, the model is installed in a fixture and adjusted in two mutually perpendicular directions located in the same plane, thereby enabling the model to be centered relative to the rotational axis of the holder. In addition, a member (parallel pin) can be utilized, which can be disposed parallel to the rotational axis and can be brought into interaction with the model material at the preparation line when the model assumes its position in the fixture. The position of the model in the fixture is in this respect such that the said contour is placed or comes between the member and the rotational axis without negative recesses and reading shadows. The fixture is placed on the holder, for example a turntable, and centered using centering members. The contour is read preferably by means of a reading member exhibiting a spherical front surface (so-called probe), which is brought to bear against the surface located below the preparation line and against the said contour.
The scanning member can be brought into physical contact with the surface below the preparation line. The physical contact remains until the scanning member, in its scanning function, has reached the upper part of the model, where the scanning member is assigned an action or a return movement which results in the cessation of the interaction of the scanning member with the model contour. The holder or scanning member can be movable in the vertical direction of the rotational axis during the scanning function. When the scanning of the contour is completed, a respective unit which is movable in the vertical direction begins return movement to the starting position.
Both the model and a sleeve (cap) which can be fitted to the model can be scanned using the scanning device. The model can be scanned first and, thereafter, the sleeve fitted onto the model. In order to avoid disturbing the set values of the model, the sleeve can be fitted with great accuracy, utilizing glue or some other adhesive material. With the double reading, the inner surface (corresponding to the outer surface of the model) and outer surface of the sleeve are fixed and data-stored.
A device for implementing the process according to the present invention is characterized principally in that a holder is arranged to support the model such that the contour of the model above a preparation line on the model can be exposed throughout the reading or scanning with the angled scanning device. The scanning device can be adjusted, at the start of the scanning function, against a surface situated below the preparation line. The holder can be activated for rotation and the reading device can be activated for contour scanning. The scanning device and the holder are arranged to perform reciprocal movements in the vertical direction of the model during the scanning function.
In one embodiment of the inventive concept, the scanning device is assigned a return movement when the scanning device has completed its contour reading, which return movement results in the cessation of a physical interaction between the scanning device and the model. The scanning device and holder respectively, can likewise be assigned a return movement when the contour scanning is completed.
In accordance with the inventive concept, the preparation model which can be read using the scanning device should be configured with a clearly marked preparation line or preparation boundary, below which there is preferably configured an indentation of no less than about 1 mm in height, calculated in the vertical direction the model, and having a depth of no greater than about 1/2mm.
The above described inventive tool is easy to handle for the dental technician and dentist. The equipment is computer-based. Despite the fact that this is a relatively new technique within dental technology, the above-mentioned proposals mean that the equipment can normally be incorporated into the ordinary working tasks of the dental technician and dentist, respectively, in connection with the provision of replacement dentures. The high level of accuracy which is sought can be satisfied throughout the production system for the particular product. The reading function can be performed separately from the rest of the production and can result in the delivery of the data-values to the manufacturer. Standardized products as regards computer equipment, modem, and the like can be utilized in this context.
BRIEF DESCRIPTION OF THE DRAWINGS
A presently proposed embodiment of a process and a device exhibiting the characteristics which are indicative of the invention will be described below with simultaneous reference to the appended drawings, in which:
FIG. 1 shows a casting, for example in plastic, of a jaw with teeth and a preparation model taken from this, in perspective section from above,
FIG. 2 shows a scanning device from the side,
FIG. 3 shows an enlarged view of parts of the device according to FIG. 2,
FIG. 4 shows parts of the scanning device according to FIG. 2, from the side,
FIG. 5 shows a personal computer unit which can be used together with the scanning device according to FIG. 2, in perspective section from above,
FIG. 6 shows the embodiment of the preparation model according to FIG. 1, in perspective section from above and in enlarged representation,
FIG. 7 shows parts of the preparation model according to FIG. 6, in longitudinal section,
FIG. 8 shows, in greater detail, a fixture for the preparation model, which can be applied to the holder, in perspective section from above,
FIG. 9 shows the fixture according to FIG. 8 as it is adjusted in a direction which is essentially perpendicular to the direction indicated in FIG. 8,
FIGS. 10-10a show preparation models which are usable and non-usable, respectively, in connection with the rest of the equipment, in perspective section from above,
FIG. 11 shows the fixture according to FIGS. 8 and 9 applied to the holder, in horizontal view,
FIG. 12 shows centering of the fixture and preparation model on the holder, in perspective view,
FIG. 13 shows an interaction between the scanning device and the preparation model mounted in the holder,
FIGS. 14-15 show menus on computer screens in connection with the scanning process, and
FIG. 16 shows the interaction of the scanning device with the model, in which a sleeve (cap) is applied to the model, in perspective section from above.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1, a conventional casting of a human jaw is indicated by 1. From the casting 1 there is extracted, in a known manner, a preparation model 2, whose contour 2ais to be read. The model is disposed on a holding part 3. The casting 1 can be made in plastic, plaster, and the like.
FIG. 2 shows a scanner 4 which is provided with a holder 5 and a scanning device 6. The holder is disposed rotatably around a rotational axis 6', and the longitudinal axis 7 of the scanning device is inclined with respect to the rotational axis 6' at an angle alpha. The angle is, in one embodiment, preferably 45°. The scanning device exhibits a longitudinally displaceable slide 8, in which the scanning device 6 is disposed. The slide is displaceable relative to the holder 5, which can be raised and lowered in the direction of the rotational axis 6'. The slide exhibits a centering part 9, which is described in greater detail below. The slide 8 is shown in FIG. 3, in which the movement direction of the slide is indicated by 10. The device includes actuating keys 11 and 12 for the movement directions of the slide and switch-on members 13 by which the scanning function can be switched on and off. The scanning device 6 comprises a front part 14 having a spherical front surface, as described below. The scanning unit has, in one embodiment, a rod-shaped configuration and operates with a scanning function based on known principles. The scanning function can be monitored on a visual display unit, as described below.
FIG. 4 shows the holder 5 in enlarged view relative to FIG. 2. The movement directions of the holder 5 are indicated by 15 and the rotary directions of the holder 5 by 16. The holder exhibits a bearing surface 5a which, in the figure, is shown in two positions, one of which is shown by continuous lines, while the other position is shown by dashed lines 5a'. The scanning device exhibits actuating keys, which can be manually operated like the keys 11, 12 and 13. The actuating members for the holder are indicated by 17, 18, 19 and 20. The actuating members 17 and 18 are utilized to adjust the rotary movement of the holder in accordance with what is stated below, while the actuating members 19 and 20 provide for raising and lowering movements 15, respectively, for the holder.
FIG. 5 shows an example of a personal computer which can be used and which can be, for example, an IBM-compatible PC comprising a processor of the 386 type or of a more powerful type. The computer can operate on a DOS 5.0 operating system or higher. The computer can comprise an internal modem and operates with at least two megabytes (MB). The personal computer can be equipped, in a known manner, with "mouse" function, color screen and can exhibit an extra I/O card. The modem can be of the telephone modem type, and a Hayes-compatible modem can be used, for example. As the communications program, a COMMUT 2.0 program from Central Point can be utilized with included software. Where scanned data is not sent by modem via a telecommunications network, the data can be sent on data files on diskette, by post or by courier.
FIGS. 6 and 7 show preferred embodiments of the preparation. The preparation model 2 should thus exhibit a clearly marked preparation line or preparation boundary 2c. The contour 2a must not exhibit any recesses or negative angles above the line 2c. The model 2 should exhibit a parallel base 2d, so that the model can be fixed in a deployed fixture, as described below. The contour should also have a shaping to prevent "shadows" being formed for the scanning member (see 14 in FIG. 3) when this operates at a fixed angle, for example 45°. It is also advantageous to dispose below the preparation line 2c a recess or depression, which is symbolized by the recess surface 2e. The recess should preferably have a height H of at least 1 mm and a depth D of 0.5 mm or less. The shaded portion 22 in FIG. 7 shows the shaping of the recess.
FIGS. 8-9 show the installation of the preparation model 2 in or on a fixture 23, which can be applied, in turn, to the holder 5. The fixture can be configured, in a known manner, with holding members for the part 2d according to FIG. 6. The fixture is in this case arranged to be able to angle-adjust the model in the directions of the arrows 24a and 24b, the tilting in the direction of the arrow 24a being managed by a manual maneuvering member 25 and the tilting in the direction of the arrow 24b being managed by a manual member 26. The model can also be tilted, in accordance with FIG. 9, in directions 27 and 27b perpendicular to the directions 24a and 24b, which directions 27 and 27b are achieved with the aid of a manual maneuvering member 28. In accordance with the figures shown, the model can be considered to have a cardan suspension in the fixture. The model is disposed in the fixture such that no recesses and preferably no scanning shadows are formed above the preparation line. The fixture permits adjustment, according to the above, in the longitudinal and transverse directions.
In accordance with FIGS. 10 and 10a, a parallelometer pin 29 can be utilized. The parallelometer pin 29 is placed parallel to the rotational axis 6' of the preparation model 2. FIG. 10 shows that the contour 2a terminates upwards/inwards as viewed from the preparation line 2c. In FIG. 10, the pin 29 therefore bears against the material at the preparation line and all the rest of the material above the preparation line is situated between the pin 29 and the rotational axis 6' This is not the case according to FIG. 10a, which shows that the pin bears against model material 2f situated above the preparation line 2c and cannot, for this reason, be accepted.
According to FIGS. 11 and 12, the fixture 23 is thereafter applied to the holder 5a. The fixture is in this case installed such that a curved surface 2g of the model is directed towards a marking 30 on a ring 31 surrounding the turntable or holder 5a. The model is centered accurately with the aid of the centering part 9 (see FIG. 2) and a plumbline 32 disposed in the part 9 and extending down towards the model 2.
According to FIG. 13, the contour scanning is initiated by the scanning device being brought into physical contact with the model 2 via its spherical front surface 14. The bearing contact takes place against the surface 2e below the preparation line 2c. The surface 14 performs movements in the direction of the longitudinal axis 7 as the contour is scanned. A bellows-shaped part which protects the scanning function is indicated by 6a. The scanning proceeds in the present case in such a way that the holder 5a is lowered downwards in the direction of the arrow 32 as the scanning takes place. When the spherical surface has scanned the whole contour 2a and reached the top 2h of the model, the scanning device 6 is assigned a return movement in the direction of the longitudinal axis 7, where the contact with the model ceases and the latter is exposed to pickup vis-a-vis the scanning device. Following completion of the scanning, the holder 5a returns to its vertical position shown in FIG. 13.
The process according to the present invention comprises an adjustment position of the scanning device as a starting position. In FIG. 13, this means that the spherical surface 14 (probe) is adjusted as far as it will go to the right in the figure. The height of the holder or turning part 5 is vertically adjusted such that the front part of the scanning member rests against the model, approximately 1 mm below the preparation line 2c. For this adjustment, the maneuvering members 11 and 12 or 17, 18 and 19, 20, respectively, can be utilized. It is advisable to avoid sudden activation movements which result in the probe hitting hard against the preparation model. The adjustment phase also includes the requirement that the spherical surface 14 should be situated below the preparation line around the whole of the model. A check of this kind can be made by rotating the model with the aid of the said maneuvering members.
The scanning procedure can thereafter be started, and the start is effected by activation of the maneuvering member 13. On the visual display unit, the "start scanning" mode can thereafter be activated, for example by actuating the activation key, the "ENTER"-key, on the computer terminal. The computer and its program there-after manage the scanning procedure, and the turntable/holder 5a is rotated and vertically displaced according to a pattern which is determined using the program, The measuring probe systematically scans the surface of the preparation model 2 until it has reached a point above the model, where it stops. When the scanning is completed, the probe automatically performs the return movement and the table regains its starting height.
FIG. 14 shows a menu on the computer screen. The menu comprises an item 1, at which the probe should be set in the starting position according to the above. According to item 2, a check is made to establish that the scanning key 13 is in the "on" position. According to item 3, "ENTER" is actuated on the computer terminal, whereupon a reading is started automatically. The program in the computer delivers or provokes control signals controlling the rotation and vertical movement (that is lowering) of the holder.
The reading by means of the scanning device and the simultaneously rotating and lowering holder/turntable is performed with respect to the contour of the model. Read data is input, in a known manner, into a particular file for subsequent use.
FIG. 15 shows an additional menu/form on which the person/dental technician can enter various information relating to the scanned tooth. "Type of transfer" can be included here. It is also possible to enter the type of copied material and whether the shape has been determined from a scanned sleeve (either titanium or ceramic) or whether it has subsequently been processed in the computer. The name of the dentist and other data can be entered, such as order number, priority, patient identification, tooth type, and the like. A space for remarks can additionally be included. The computer is then activated for "save data file" and the scanning is complete. Information or data which have been scanned and stored in the computer can be transferred, according to the above, to the manufacturer.
FIG. 16 shows a scanning function for a sleeve 33 (cap). The inner contour of the sleeve 33 is scanned in accordance with the above, that is the outer contour of the preparation model 2 corresponds to the inner contour of the sleeve 33. This scanning is carried out according to the above. The sleeve 33 is thereafter applied to the model and care should be taken in this respect to ensure that adjustments which have been made for the model are not affected. The sleeve can be glued to the model. The system coordinates the two scannings of the inner and outer surfaces by using the same system of coordinates. This means, for example, that the starting position for the scanning device relative to the model must be the same, that is the scanning device must be applied to that same point or position which was utilized when only the model was scanned. Once the sleeve has been fixed on the model, the procedure according to the above can be repeated for scanning of the outer contour of the sleeve. The difference is, however, that a difference emerges in the height of the turntable, which must be adjusted. The maneuvering members for the turntable can be utilized in this respect. The computer can be arranged to identify automatically the starting point for previous scanning of the surface 2a, which requires that the position for the fixture relative to the turntable has not been altered. On the menu or form of the dental technician, there can be entered supplementary information stating that the scanning relates to an outer surface of a sleeve in question.
The invention is not limited to the embodiment shown by way of example above, but can be subject to modifications within the scope of the subsequent patent claims and the inventive concept. | A method and device for scanning, in connection with the production of a three-dimensional body, an outer contour of a rotating model with a scanning device operating at a scanning angle relative to the rotational axis of the model includes rotatably supporting the model such that the contour to be scanned on the model has a preparation line exposed to the angled scanning device; applying the scanning device towards a surface situated on the model below the preparation line; scanning the contour with the scanning device while simultaneously rotating the model and vertically moving at least one of the scanning device and the model with respect to each other during the contour scanning. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a truck material discharge apparatus. More particularly, the present invention is directed to a dump truck attachment for use in road repair.
2. Description of the Prior Art
A variety of factors require periodic roadway surface maintenance. It is necessary to repair road surfaces when holes, cracks or other surface deteriorations appear due to heavy traffic conditions or weather erosion. Each hole in a roadway surface must be filled with roadway repair material so that the hole is plugged and flush with the rest of the roadway surface.
It has been the practice in the prior art to hand shovel a quantity of road repair material from the body of a truck. Considerable manual labor is required in order to repair the roads. As a result, methods of road repair, which reduce the amount of manual labor and facilitate the road repair operation are in demand.
One example of these methods is found in U.S. Pat. No. 1,563,202 to Lentz, which is directed to a road patch material spreader for use on a dump truck. The material spreader is a flat, substantially horizontal shelf that attaches to the back of a dump truck body and extends the width of the body. The shelf is located behind the truck body to receive road repair material from the dump box of a truck. The dump box may be raised to allow gravity to roll the repair material back toward the pan. An agitator shaft expels the repair material.
U.S. Pat. No. 2,253,248 to Palmer is directed to a spreader box attached to the rear of a dump truck to receive repair material from a dump box. The device facilitates the spreading of repair material over a road bed directly from the dump box without the aid of manual labor or from the top of the box by a shovel held by a laborer.
U.S. Pat. No. 2,997,213 to Richards et al. discloses a material discharge control attachment for dispensing a repair mixture on the roadway surface from a dump truck. The attachment is located at the rear of the dump truck and extends the entire width of the dump truck and also to the ground level. It has a number of chutes with doors, which are lifted to allow the material to drop onto the roadway surface.
U.S. Pat. No. 3,552,346 to Garden discloses a sand-bagging device which attaches to the rear end of a dump truck for filling up bags with sand or soil from the truck body. The device is related since it attaches to the rear of a truck body and is situated to receive material from the dump box.
The prior art devices have some disadvantages. First, they are difficult to attach to the truck body as they generally require many attachment points along the rear end of the truck. Further, the devices cannot be readily removed or replaced on the truck body.
Another disadvantage is the large size of the prior art devices. Each of the described devices extends the width of the rear of a dump truck body. When they are attached, they are virtually immovable. There may be times when a truck operator will use the truck containment box for purposes other than road repair. In those instances it can be difficult to use the truck since the prior art devices would be in the way of or prevent any other type of use. Further, the cumbersome devices of the prior art impede free movement of the vehicle since it is difficult to drive a truck at normal road speeds with such an attachment.
SUMMARY
The above-mentioned disadvantages are overcome by the present invention which is directed to a patching pan device for use with a vehicle having a material containment bed with a material distribution opening and a spinner attachment shaft. The patching pan includes a material distribution pan adapted to be detachable along with a means rotatably mounting the pan to the vehicle and positioning the pan to receive material from a distribution opening. In a first operating position, the patching pan is located below the distribution opening and a second stored position locates the pan away from the opening. The device further includes a collar for rotatably mounting the pan to a shaft attached to the vehicle. The device may be used with a vehicle such as a truck having a dump body or a V-box.
The patching pan of the present invention is configured to connect to a truck "spinner shaft." The spinner shaft is a permanently mounted, generally vertically disposed shaft used to connect a sand or salt spreader, also known as a "spinner," during the winter. When the spinner is removed, the patching pan is readily interchangeable and attaches directly to the spinner attachment shaft.
An advantage of the present invention is that it is an efficient use of municipal resources. The patching pan provides a means by which trucks configured for winter salt-spreading or sand-spreading may be employed during the summer months for road repair. Further, the patching pan is made to have variable positions such that in a first operating position it is located to receive road repair material from a discharge passage. It may be moved to a second storage position such that it is away from the discharge passage under the truck or into another position not interfering with other operations of the truck. Further, the attachment may be easily attached or detached from the truck to allow the truck to be used for other purposes. The device does not require customization of the truck body.
Reference is now made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a patching pan attached to the rear of a truck.
FIG. 2 is a perspective view of the patching pan illustrated in FIG. 1 from a right side perspective.
FIG. 3 is a perspective view of the patching pan from the vantage point shown in FIG. 1 illustrating it in a second pivot position under the truck bed.
FIG. 4 is a top partial cross-sectional view of the patching pan taken along lines 4--4 of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference is now made to the figures. In the figures, similar components will have the same reference numerals throughout the several drawings. The present invention illustrated in FIG. 1 is a patching pan device 10 that may be used with a truck 12, known to the art, to receive patching material such as asphalt or the like and temporarily contain it for easy access by a worker. The truck may be any type of vehicle that is configured to contain material such as asphalt. In the preferred embodiment the truck 12 includes a dump box or a V-box, both of which are referred to by reference number 22. A dump box is a rectangular material holding bin that tilts up from a front end of a truck with a downward slope toward the rear of the truck or from one side of a truck to the other side. A V-box is a rectangular material holding bin that has side walls sloping in a V-shape with the open end up. Either type of box 22 may be fitted with a conveyor mechanism to move material from one end to another or from side to side.
The patching pan device 10 includes a receiving platform 14 from which the material is removed to repair roads or other driving surfaces, in the preferred embodiment. However, it may be used for gravel conveyance or landscaping work as well. The receiving platform 14 includes a substantially horizontal base sheet 16 with a substantially vertical wall 18 bordering most of the perimeter. Attached to the platform 14 is a connection means 20 for connecting the platform 14 to the truck 12 at the rear of truck box 22. The base sheet 16 includes an upper surface 28 into which road repair material is urged from the truck box 22, a lower second surface 30 and an edge 31. The base sheet 16 may also be provided with a rearward slope to engage the use of gravity in discharging road repair material. As illustrated in the figures, the receiving platform 14 is configured with six sides in the preferred embodiment to optimize material removal and platform 14 storage. The six-sided configuration is specific to a particular style of truck. Any configuration may be integrated depending upon the type of truck utilized.
A lip 32, integral with the sheet 16, depends at a downward angle from the sheet 16 in order to facilitate easy removal of repair material. The lip 32 includes a first side 34, a second side 36, a lower edge 38 and two side ends 40. Since repair material may be removed from the platform 14 by shoveling or scooping, the lip edge 38 provides a directional aid to the shovel when the shovel may be aimed slightly too low; in such an instance, the shovel will be nudged upward onto the upper surface 28 of the base sheet 16. The lip 32 further functions as an exit ramp for the repair material if the material is urged from the base sheet 16 directly to the ground.
Integral with the sheet edge 31 and depending in an upward direction from the base sheet 16 is the vertical wall 18. The vertical wall 18 provides a barrier for containing repair material. In the preferred embodiment, the wall 18 is disposed at the sheet edge 31 on four edges of the six-edged sheet 16. A portion of the sheet 16 remains open or unwalled to provide an opening or exit for the repair material and an entrance for the shovel. As repair material drops onto the sheet 16 from the truck 12, the wall 18 contains the material preventing it from falling in the wrong direction. Further, the wall 18 provides a backstop, forcing repair material onto a scoop or shovel when a shovel edge is pushed through the material adjacent to the wall 18.
Attached to the second surface 30 of the sheet 16 is an arm 42 illustrated in FIGS. 2, 3 and 4. The arm 42 has a substantially horizontal upper first side 44, a lower second side 46, side edges 48 and an end 50. The arm 42 extends from under the second surface 30 of the receiving platform 14 at an angle toward the rear of the truck 12. The arm may be attached to the second surface 30 by welding or other conventional means known to the art.
Joined to the first side 44 of the arm 42 is a substantially vertical cylindrical collar 51, which is substantially perpendicular to the first side 44 of the arm 42. The collar 51 is hollow and cylindrical, and provides a passage for attachment to the truck 12. The collar 51 has a first end 52 attached to the arm first side 44 and a second open end 53 as shown in FIG. 2.
A locking means including a plate 55 is attached to the collar second end 53. The plate 55 provides a rotational locking mechanism for the platform 14. Apertures 59 within the perimeter of the plate 55 allow a stationary pin 57 to be positioned therethrough preventing the plate 55 from pivoting and thereby preventing collar 51 and platform 14 rotation. The pin 57 may be attached to plate 55 by a retaining rope 59a to prevent loss of the pin 57.
An angled shoulder 54 is joined to the collar 51 along its length providing support to maintain the collar in a substantially vertical position. Triangular shaped, the shoulder 54 has opposing sides 56, a first edge 58, a second edge 60 and a third edge 62. The shoulder first edge 58 joins with the collar 51 and the shoulder second edge 60 joins with the arm first side 44. The shoulder 54 is welded to the collar 51 and the arm first side 44 in the preferred embodiment.
The patching pan device 10 is releasibly connected to the truck 12 in the following manner. The truck 12 is typically provided with a downwardly depending cylindrical "spinner" shaft 64 primarily for receiving a sand or salt "spinner" depenser known to the art. The shaft 64 has a first end, not shown, a second end 68 and an outer surface 70. The second end 68 is attached to the truck 12. By slipping the collar 51 over the shaft 64 until the shaft 64 protrudes below the collar 51, the shaft 64 may be secured preventing the collar 51 from slipping off. Connection is accomplished by attaching the collar 51 to the shaft 64 according to many attachment means known to the art including a cotter pin inserted through the shaft first end, or by providing for a threaded shaft first end onto which a fastener may be torqued. The shaft outer surface 70 provides a bearing-like mechanism when inserted within the collar 51 to allow pivoting of the collar 51 and thereby the entire platform 14.
Pivoting the collar 51 is necessary to allow the platform 14 to be positioned at various locations. The platform 14 may be pivoted out of the way into a position directly below the rear of the truck 12 when the truck 12 is moving from one working location to another as illustrated in FIG. 3. When the truck 12 reaches its job site, the platform 14 may be pivoted out from below the truck into a working position to the rear of the truck 12 below the material opening as illustrated in FIGS. 1 and 2. Further, the platform 14 may be positioned at variable locations between the fully operational position and the storage position as shown with phantom lines in FIG. 4.
In operation, road repair material, which is asphalt in the preferred embodiment, is contained in the truck box 22. The truck box 22 may be configured with a conveyor 72 disposed on the box 22 floor between the box 22 sides. The conveyor 72 may be turned on to move material from forward in the box 22 toward a rear opening 74. The asphalt is urged through the rear opening 74 by the conveyor 72 and gravity assisted by an inclined box floor; dropping vertically onto the platform 14 when it is in a working position. With or without a conveyor, a dump box may be inclined to urge the asphalt towards the truck rear opening. Workers behind the truck 12 may push the asphalt over the lip 32 onto the road surface or shovel it out using the wall 18 as a backstop for the asphalt. Controls for the conveyor 72 and truck box 24 may be conveniently located at the rear of the truck 12 to control asphalt flow. After the job is completed the stationary pin 57 can be disengaged to pivot the platform 14 under the truck 12 where the pin 57 is then replaced to lock the platform in a storage position.
The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. Therefore, all suitable modifications and equivalents fall within the scope of the invention. | The patching pan is a device for use with a truck having a material containment bed with a material distribution opening. The patching pan is rotatably and detachably mounted to the truck. In a first position, patching material is urged through the distribution opening onto the patching pan from which the material may be easily removed. In a second position, the patching pan is located below the material containment bed out-of-the-way such that the truck may move freely from one location to another. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
[0003] THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
[0004] Not Applicable
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
[0005] Not Applicable
BACKGROUND OF THE INVENTION
[0006] 1. Field of the Invention
[0007] This invention relates to improvements in a front facing sitting pillow. More particularly, the present front facing sitting pillow mounts or sits on a table desk or tray to allow a person to lean forward and place their face into the pillow. The pillow allows a person to sit at a desk, airplane seat or similar, and sleep is a forward facing position.
[0008] 2. Description of Related Art
[0009] including information disclosed under 37 CFR 1.97 and 1.98.
[0010] When traveling on a bus, plane or train a person typically will lay back or to a side to rest or sleep. Some people choose to rock forward and rest their head in their hands and they place their elbows on a desk, table or tray. This makes it difficult to comfortably sleep and often when a person falls asleep the person loses muscle tension in their arms and the head will drop to wake the person. There have been several patents for supporting a face when a person is laying forward to get a massage, but these patents support and entire body and are not supported or mounted on an existing table or desk.
[0011] A number of patents and or publications have been made to address these issues. Exemplary examples of patents and or publication that try to address this/these problem(s) are identified and discussed below.
[0012] U.S. Pat. No. 4,662,361 issued May 5, 1987 to Merrill Patterson discloses a Physical Therapy Chair. The chair requires a person the sit on the chair and lean forward to place their forehead on a pad. The person can then get a back massage or adjustment while seated in the chair. While the patent allows a person the sit in the chair and lay forward to rest, the invention is not supported on a desk or table and further, the invention does not support the chin to prevent the head from dropping if the person falls asleep.
[0013] U.S. Pat. No. 4,971,040 issued Nov. 20, 1990 to Michael A. Gillotti discloses a Portable massage chair. A person places their legs through the chair and lays forward. The chair allows a person to place their chest on the front support and to receive a back massage. While the patent provides support for the chest of a person, the invention is not supported on a desk or table and the invention does not support the chin of a person to prevent the person from slumping down.
[0014] U.S. Pat. No. 5,401,078 issued on Mar. 28, 1993 for Linda A. Riach and U.S. Pat. No. 5,762,402 issued on Jun. 9, 1998 to Muchael Gillotti both discloses an Adjustable Therapy or Massage Chair. In these chairs a person kneels forward with the majority of the weight distributed on the shins, posterior and chest. The arms of the user are usually crossed in front of the user. A person places their face in an inverted “U” that supports the forehead of the person getting a massage or therapy. While this allows a person to rest in a forward orientation it is not configured to be supported on a desk table or tray where a traveler can easily carry and transport the face and head of the traveler.
[0015] What is needed is a pillow that supports the face and head of a user as they rest in a forward laying orientation. The ideal product rests or mounts on a table, desk or tray. The proposed front facing sitting pillow provides the solution.
BRIEF SUMMARY OF THE INVENTION
[0016] It is an object of the front facing sitting pillow to mount or sit on a table desk or tray. For people that are in a restricted seat, like on an airplane seat, the person in a seat has limited access to the floor or other structure. From an airplane seat a person has a fold-down tray where the person can place items for work or leisure use. The front facing pillow is configured to would onto the thin fold-down tray or onto a desk surface to secure the front facing pillow. The front facing sitting pillow has a central opening where a person can read or look through the opening. It is also possible to provide eye shields to block light and therefore provide a darker atmosphere.
[0017] It is an object of the front facing sitting pillow to provide support for a person as they lay forward. Because a person does not have any support in a forward position it forces a person into lying against a seat, or resting to a side. With this front facing sitting pillow the person can lean forward where the face of the person can be held in a captured position. The mounting of the front facing sitting pillow on the tray provides a semi-ridged support that not only supports the person from forward motion but also prevents the head from tipping side-to-side when the person falls asleep.
[0018] It is another object of the front facing sitting pillow to be adjustable to accommodate different geometry of users. The face of each user can be different from the spacing of the cheeks and from the overall height of a person where they lay forward. The front facing sitting pillow is adjustable to place the pillow at a position where the pillow is essentially neutral when the person is resting to prevent neck stain as they rest. The sides can be moved further apart or set at an angle to accommodate the desire of a person that is resting.
[0019] It is still another object of the front facing sitting pillow for the pillow to be cleanable or washable. The pillows are covered with a cushioned fabric material and can be changed to accommodate style, cushion and tactile surface features. The cover is removable to allow them to be cleaned, or replaced. They are essentially socks that slide over the ends of the side supports.
[0020] Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0021] FIG. 1 shows a perspective view of the front facing sitting pillow in use.
[0022] FIG. 2 shows a perspective view of the front facing pillow.
[0023] FIG. 3 shows a side view of the front facing pillow.
[0024] FIG. 4 shows a perspective view of the front facing pillow folded for transportation and storage.
[0025] FIG. 5 shows a front perspective view of a second preferred embodiment of the front facing sitting pillow.
[0026] FIG. 6 shows a rear perspective view of the second preferred embodiment of the front facing sitting pillow with the pillow displaced.
DETAILED DESCRIPTION OF THE INVENTION
[0027] FIG. 1 shows a perspective view of the front facing pillow 20 in use and FIG. 2 shows a perspective view of the front facing pillow. From these figures the user 10 is resting in a forward seated position with the chin 11 of the user 10 placed in the lower “U” 21 of the face pillow 20 . Above and on the sides of the lower “U” are cheek pads 22 and 23 . The cheek pads 22 and 23 support the front of the face and head 24 to prevent the face and head 24 from drooping forward when the user 10 falls asleep. It is also contemplated to provide eye shields to block light and therefore provide a darker atmosphere to make sleeping easier.
[0028] The cheek pads can be configured to cover the eyes to block light or can be configured in an open configuration that allows the user to see in front of the cheek pads 22 and 23 to allow a user 10 to read a book, cell phone, tablet or other item. The front facing pillow 25 is configured as a single solid member or can be configured with articulating cheek pads that can be adjusted to contour to the sides of the face of a user 10 . The front of the pillow 20 can be covered with a removable covering 26 that can be removed for cleaning and washing.
[0029] The front facing pillow 25 is connected 26 to the remainder of the securing mechanism with a pivoting connection 30 that allows the front facing pillow 25 to rotate to allow the user 10 to set the desired angle where the head/face will be placed to place the user's head at a neutral position to reduce or prevent neck strain as the person rests or sleeps. From the pivoting connection 30 a pair of side arms 31 and 32 extend to rear pivoting joints 33 and 34 .
[0030] The rear pivoting joints 33 and 34 allow the vertical position of the front facing pillow 25 to be set. From the rear pivoting joints 33 and 34 a set of arms 36 and 37 extend to front pivoting joints. 38 and 39 . The combination of arms 31 , 32 and 36 , 37 allow for both vertical positioning of the front facing pillow 25 and the some front-to-back positioning of the front facing pillow 25 relative to the front 50 of where the front facing pillow 20 is mounted.
[0031] From the front pivoting joints 38 and 39 a pair of plates 51 and 52 are positioned to capture and grasp an existing tray 49 . When the plates 51 and 52 grasp the tray 49 they are secured to the existing tray 49 to prevent undesired side-to-side movement and rotation that might prevent the front facing pillow 20 from becoming accidentally dislodged from the existing tray 49 .
[0032] FIG. 3 shows a side view of the front facing pillow 20 . From this side view the gap 43 that separates the upper plate 51 from the lower plate 52 is more visible. This gap 43 is adjustable to accommodate trays that may have different thicknesses. For installation the upper plate 51 is spread from the lower plate 52 . The plates are then place on the side of the existing fold-down tray 49 (not shown in this figure) and then the plates 51 , 52 are brought together to essentially clamp the plates 51 and 52 on the fold-down tray 49 .
[0033] The upper plate 51 and the lower plate 52 pivot from front pivoting joint 38 . A thumbscrew 42 provides frictional tension to the front pivoting joint 38 , the upper plate 51 , the lower plate 52 and arm 36 . While a thumbscrew 42 is shown to provide friction, it is also contemplated that detents could be used to provide positive positioning stops. Arm 36 is connected to rear pivoting joint 34 . At joint 34 another thumbscrew 41 is shown to provide frictional movement. This connection could also include detents. From joint arm 32 connects to pivoting connection 30 with a thumbscrew 40 or other friction connection to that connects to the pillow support.
[0034] The pillow support includes the cheek pads 22 connected through the “U” chin support 21 . This figure shows a cover 27 that is removable and provides a covering of cushioned fabric material and can be changed to accommodate style, cushion and tactile surface features. The cover is removable to allow them to be cleaned, or replaced. They are essentially socks that slide over the ends of the side supports and can connect in the chin area to essentially cover the entire surface where the skin of a person can make contact with the front facing pillow 20 .
[0035] FIG. 4 shows a perspective view of the front facing pillow 20 folded for transportation and storage. This figure shows that the front facing pillow 20 is folded to a size that approximates a laptop computer or tablet computer. The upper plate 51 and the lower plate 52 are brought together using front pivoting joints 38 and 39 . The pivoting joints 38 and 39 allow arms 37 and 36 (not visible) to fold along the sides of the upper plate 51 and the lower plate 52 . At the end of arms 37 and 36 rear pivoting joints 33 and 34 sit adjacent to the back of the upper plate 51 and the lower plate 52 . Pivoting joints 33 and 34 have side arms 31 and 32 extending to pivoting connection 30 that has a connection 26 to the face pillow.
[0036] The face pillow is articulated back against the upper plate 51 where the “U” chin support cheek pads 22 and 23 rest in proximity to the upper plate 51 . It is further contemplated that the parts can telescope together to reduce the width of the front facing pillow 20 for transportation. While this particular folded embodiment is shown and described other equivalent embodiments are contemplated that provide a support that allows a person to rest in a forward position and allows a person to fold the front facing pillow 20 in a compact package for transportation. In addition to the disclosed folding arrangement it is also contemplated to provide a telescoping adjustment for the position of the face support.
[0037] FIG. 5 shows a front perspective view of a second preferred embodiment of the front facing sitting pillow 120 and FIG. 6 shows a rear perspective view of the second preferred embodiment of the front facing sitting pillow 120 with the pillow 191 displaced. In the second preferred embodiment the base tube 150 is curved to provide a base structure. The base tube has a plurality of feet or cushions 140 , 141 and 142 to protect the table, desk or other supporting surface and also increases the coefficient of friction between the base tube 150 and a supporting table or desk. Fastening hardware 143 and 144 secures the feet or other elements to the base tube 150 .
[0038] At the front of the base tube 150 is a tube connector 130 with a plurality of holes 132 and 133 . A spring loaded button 131 allows the vertical tube member 134 to be rotated on the base tube 150 to alter an angular relationship 197 between the base tube 150 and the vertical tube member 134 . While vertical tube member 134 is identified as “vertical” it should be understood that the vertical tube member 134 can be positioned at different angles other that only vertical with respect to the planar bottom created by the base tube 150 .
[0039] The vertical tube 134 has in internal telescoping tube 135 that is extendable from within the vertical tube 134 . The telescoping tube 135 is secured within the vertical tube 134 with another spring loaded button 136 . This spring loaded button 136 is used to extend or retract 198 the pillow 191 . The telescoping tube 135 is secured to a cross member 136 .
[0040] The cross-member 136 extends horizontally to support arms 170 , 171 , 172 and 173 . These support arms are secured at a first end with a clamp 160 that essentially extend from one end of the cross-member 136 to the other end of the cross-member 136 . In the preferred embodiment a threaded member is used within the cross-member 136 to clamp the opposing ends with one or more nuts at both ends. In this figure, a threaded cam clamp 160 is used to allow for quick release and tightening of the cross-member 136 and the support arms 170 , 171 , 172 and 173 . The support arms 170 , 171 , 172 and 173 can slide on the ends of the cross-member 136 through pivoting axle 161 .
[0041] Support arms 170 , 171 , 172 and 173 are partially slotted at the first end and join the back of the support plate 190 at pivot locations to allow the support arms 170 , 171 , 172 and 173 to pivot on the back of the support plate 190 through pivoting axles 162 and 163 to change 199 the angle of the support plate 190 relative to the telescoping tube 135 and ultimately to the base tube 150 and the table or desk. The support plate 190 provides support to the face pad 191 .
[0042] The face pad 191 is recurred and or optionally removable from the support plate 190 with hook-and-loop fasteners 192 or other equivalent securing mechanism. The face pad 191 is removable for cleaning, washing or replacement.
[0043] The multiple adjustments allows a person to position the face pad 191 in an optimal position for comfort of the user that wants to take a nap while facing forward. A user can place their arms on the base tube 150 to reduce movement of the base tube on the desk or table while they nap or rest.
[0044] Thus, specific embodiments of a front facing sitting pillow have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. | Improvements in a front facing sitting pillow that mounts or sits on a table desk or tray. For people that are in a restricted seat, like on an airplane seat, the person in a seat has limited access to the floor or other structure. From an airplane seat a person has a fold-down tray where the person can place items for work or leisure use. The front facing sitting pillow is adjustable to accommodate different geometry of users and place the pillow at a position where the pillow is essentially neutral when the person is resting to prevent neck stain as they rest. The sides can be moved further apart or set at an angle to accommodate the desire of a person that is resting. The pillow(s) are covered with a cushioned fabric material that is removable to allow them to be cleaned, or replaced. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a process for preparing fluorine-containing dimethylchlorosilanes in high yields by a reaction between an ethylene compound having a fluorine-containing organic group and dimethylchlorosilane.
2. Description of the Prior Art
It is well known that fluorine-containing dimethylchlorosilanes can be obtained by reacting a fluorine-containing alkylethylene with dimethylchlorosilane. This reaction is represented by the following reaction formula: ##STR1## wherein Rf is a fluorine-containing organic.
Conventionally, the above reaction has been carried out using a platinum complex or a peroxide as a catalyst. The conventional method has the problem that the desired product can be obtained only in low yield.
SUMMARY OF THE INVENTION
Accordingly it is an object of this invention to provide a process for preparing fluorine-containing dimethylchlorosilanes in high yields by a reaction of an ethylene compound having a fluorine-containing organic group, such as a fluorine-containing alkylethylene, with dimethylchlorosilane.
According to this invention, there is provided a process for preparing a fluorine-containing dimethylchlorosilane, which comprises reacting an ethylene compound having a fluorine-containing organic group with dimethylchlorosilane in the presence of a rhodium complex.
By the use of a rhodium complex as a reaction catalyst, it has become possible to obtain fluorine-containing dimethylchlorosilanes in shorter time and in higher yield, as compared with the conventional processes.
DETAILED DESCRIPTION OF THE INVENTION
Ethylene compound
The ethylene compound used as a starting material in this invention has, for example, the following formula:
Rf--CH═CH.sub.2
Wherein Rf is a monovalent fluorine-containing organic group, or
CH.sub.2 ═CH--Rf'--CH═CH.sub.2
wherein Rf' is a divalent fluorine-containing organic group.
The monovalent fluorine-containing organic group Rf includes, for example, perfluoroalkyl groups having the formula:
C.sub.1 F.sub.21+1-
wherein 1 is an integer of 1 or above, preferably from 1 to 10, perfluoroalkyl ether groups having the formula: ##STR2## wherein n is an integer of 0 or above, preferably from 0 to 10, and groups which are derived from these groups by substitution of hydrogen atoms for part of the fluorine atoms in these group.
The divalent fluorine-containing organic groups Rf' includes, for example, perfluoroalkylene groups having the formula:
--C.sub.m F.sub.2m-
wherein m is an integer of 1 or above, preferably from 1 to 10, perfluoroalkylene ether groups having the formula: ##STR3## wherein p and q are integers of 0 or above, preferably such integers that p+q is from 0 to 10, and groups which are derived from these groups by substitution of hydrogen atoms for part of the fluorine atoms in these groups.
Of the ethylene compounds having the monovalent or divalent fluorine-containing organic group as mentioned above, those which are particularly preferred for use in this invention include the followings: ##STR4##
Rhodium complex
Preferable examples of the rhodium complex to be used as a reaction catalyst in the process of this invention include RhCl(PPh 3 ) 3 , RhCl(CO)(PPh 3 ) 2 , [Rh(CH 3 COO) 2 ] 2 , [RhCl(C 2 H 4 ) 2 ] 2 , [RhCl(C 7 H 8 )] 2 (wherein C 7 H 8 is norbornadiene as a divalent ligand), Rh(CH 3 COCHCOCH 3 ) 3 , etc. In the above formulas, and hereinafter, Ph stands for the phenyl group.
The rhodium complexes are used preferably in an amount of from 1.0×10 -8 to 1.0×10 -1 mole, more preferably from 1.0×10 -6 to 1.0×10 31 3 mole, per mole of the ethylene compound.
Reaction
The reaction between the ethylene compound having a fluorine-containing organic group and dimethylchlorosilane is carried out in the presence of the rhodium complex at a pressure of preferably 2 atm or above, more preferably from 4 to 10 atm, and a temperature of from 50° to 250° C., preferably from 70° to 150° C. The reaction under these conditions is carried out, for example, in an autoclave.
In carrying out the reaction, it is generally desirable to use dimethylchlorosilane in an amount of from 1.0 to 5.0 moles, preferably from 1.1 to 2.0 moles, per mole of an ethylenic double bond contained in the ethylene compound.
The reaction proceeds according to the aforementioned reaction formula. For example, when the ethylene compound used is a monofunctional one, a fluorine-containing dimethylchlorosilane having the following general formula [I]: ##STR5## wherein Rf is a monovalent fluorine-containing organic group, is obtained in a high yield. The fluorine-containing dimethylchlorosilane thus obtained is useful as a silylating agent, a silica treating agent, a raw material for surfactants, etc.
When a bifunctional ethylene compound is used, on the other hand, the aforementioned reaction produces a dimethylchlorosilane having the following general formula [II]: ##STR6## wherein Rf' is a divalent fluorine-containing organic group. This dimethylchlorosilane is useful as a raw material for hybrid silicones having a fluorine-modified backbone.
EXAMPLES
Example 1
A 300-ml autoclave equipped with a stirrer and a thermometer was charged with 179 g of n-C 4 F 9 CH═CH 2 , 98 g of dimethylchlorosilane and 0.11 g of RhCl(PPh 3 ) 3 (Wilkinson's complex), and the resultant mixture was stirred with heating at 100° C. under a pressure of 7 atm for 4 hours.
After the reaction, the reaction product was cooled to 25° C. and taken out of the autoclave. A quantitative analysis of the reaction product by gas chromatography gave a conversion of n-C 4 F 9 CH═CH 2 of 93% and a selectivity of 93% for dimethylchlorosilane having the following formula: ##STR7##
Example 2
The same 300-ml autoclave as that used in Example 1 was charged with 177 g of CH 2 ═CHC 6 F 12 CH═CH 2 , 122 g of dimethylchlorosilane and 0.08 g of RhCl(PPh 3 ) 3 , and the resultant mixture was stirred with heating at 110° C. and 8 atm for 6 hours.
After the reaction, the reaction product was quantitatively analyzed in the same manner as in Example 1. The analysis gave a conversion of CH 2 ═CHC 6 F 12 CH═CH 2 of 99% and a selectivity of 79% for the addition reaction product having the following formula: ##STR8##
Example 3
The same 300-ml autoclave as that used in Example 1 was charged with 239 g of ##STR9## 61 g of dimethylchlorosilane and 0.09 g of RhCl(PPh 3 ) 3 , and the resulting mixture was stirred with heating at 100° C. and 6 atm for 6 hours.
After the reaction, the reaction product was analyzed quantitatively in the same manner as in Example 1. The conversion of the HFPO trimer-ethylene was 86%, and the selectivity for the addition product having the following formula: ##STR10## was 88%.
Examples 4-7
Reactions were carried out in the same manner as in Example 1 except that 0.1 g each of other rhodium catalysts were used in place of RhCl(PPh 3 ) 3 . The results are shown in Table 1 below.
TABLE 1______________________________________ Conversion SelectivityExample Catalyst (%) (%)______________________________________4 [Rh(CH.sub.3 COO).sub.2 ].sub.2 87 895 RhCl(CO)(PPH.sub.3).sub.2 88 926 [RhCl(C.sub.2 H.sub.4).sub.2 ].sub.2 81 907 Rh(CH.sub.3 COCHCOCH.sub.3).sub.3 82 87______________________________________
Comparative Examples 1-8
Reactions were carried out in the same manner as in Example 1 except that various catalysts were used in place of RhCl(PPh 3 ) 3 . The results, such as the selectivity for the desired addition product, are shown in Table 2 below.
TABLE 2______________________________________Compar- Amount Con-ative of catalyst version SelectivityExample Catalyst (g) (%) (%)______________________________________1 H.sub.2 PtCl.sub.6.6H.sub.2 O 0.1 66 932 (t-BuO--).sub.2 -- 1.2 52 893 PdCl.sub.2 (PPh.sub.3).sub.2 0.1 44 914 PtCl.sub.2 (PPh.sub.3).sub.2 0.1 5 945 Mo(Co).sub.6 0.06 36 886 IrCl(CO)(PPh.sub.3).sub.2 0.1 12 957 Ru.sub.3 (CO).sub.12 0.1 19 908 RuCl.sub.2 (PPh.sub.3).sub.3 0.1 7 92______________________________________ | Fluorine-containing dimethylchlorosilanes are prepared by reacting an ethylene compound having a fluorine-containing organic group with dimethylchlorosilane in the presence of a rhodium complex, for instance RhCl(PPh 3 ) (Ph: phenyl group), as a catalyst. The use of a rhodium complex as a catalyst enables preparation in high yield of the fluorine-containing dimethylchlorosilane, which has been heretofore obtainable only in low yields. | 2 |
BACKGROUND
[0001] The present invention relates generally to signal quality estimation in a mobile communication network and, more particularly, to signal quality estimation for the uplink in LTE systems.
[0002] Long Term Evolution (LTE) systems use single-carrier frequency-division multiple-access (SC-FDMA) for uplink transmissions. The use of single carrier modulation for the uplink is motivated by the lower peak-to-average ratio of the transmitted signal compared to conventional OFDM, which results in higher average transmit power and increased power amplifier efficiency. The use of SC-FDMA in the uplink, however, gives rise to an inter-symbol interference (ISI) in dispersive channels. It is important to mitigate the effects of ISI so that SC-FDMA can improve power amplifier efficiency without sacrificing performance.
[0003] Linear minimum mean square error (LMMSE) receivers in the base station (also known as an eNodeB) can suppress ISI using linear frequency domain equalization. LMMSE receivers are designed to maximize the signal-to-interference-plus-noise ratio (SINR) for each subcarrier component. Though LMMSE improves performance significantly beyond a simple match filtering receiver, further improvements in performance could be obtained with advanced receivers using techniques such as Turbo Soft Interference Cancellation (TuboSIC), or near maximum-likelihood detectors, such as a reduced state sequence estimator (RSSE), Serial Localization with Indecision (SLI) and Assisted Maximum Likelihood Detector (AMLD). These advance receivers are expected to achieve performance very close to the performance of a maximum-likelihood detector.
[0004] One problem encountered with the deployment of advanced receivers is obtaining reliable channel quality indication (CQI) estimation and modulation and coding scheme (MCS) selection. CQI estimates are used, for example, for link adaptation and scheduling in the uplink of LTE. Currently, there is no solution for CQI estimation for RSSE, SLI, MLD, or other ML, or near ML, receiver in the uplink in LTE systems.
SUMMARY
[0005] The present invention relates to the estimation of signal-to-interference-plus-noise ratios in multi-user receivers using ML or near ML detectors for the uplink of an LTE system. The embodiments of the present invention enable more accurate CQI estimation and MCS selection for multi-user single input, multiple output (MU-SIMO), single user multiple input, multiple output (SU-MIMO), and multiple user multiple input, multiple output (MU-MIMO) uplinks in LTE. The present invention can be applied to scheduling multiple uplink transmissions on the same frequencies (i.e., multi-user MIMO).
[0006] On exemplary embodiment of the invention comprises a method of determining a transmission format for uplink transmissions over a MIMO channel. One exemplary method comprises receiving two or more signals of interest over a multiple-input, multiple-output channel; iteratively detecting each signal-of-interest by successive interference cancellation and jointly detecting symbols within each signal-of-interest; and computing a signal-to-interference-plus-noise ratio for each signal-of-interest reflecting the remaining interference after cancellation of interference attributable to previously detected signals-of-interest. The signal-to-interference-plus-noise ratio may be computed by computing per-subcarrier signal-to-interference-plus-noise ratios for a plurality of subcarriers allocated to the signal-of-interest; and computing a total signal-to-interference-plus-noise ratio for the signal-of-interest based on the per-subcarrier signal-to-interference-plus-noise ratios of the subcarriers. The computed signal-to-interference-plus-noise ratios for the signals-of-interest are used to determine transmission formats for uplink transmissions.
[0007] Another exemplary embodiment of the invention comprises a receive signal processor for a communications device having one or more receive antennas. The receive signal processor comprises a detector to iteratively detect two or more signals-of-interest received over a multiple-input, multiple-output channel, and a signal quality estimator to compute a signal-to-interference-plus-noise ratio for the signal-of-interest reflecting the remaining interference after cancellation of interference attributable to the previously detected signals-of-interest. The detector jointly detects the symbols in each signal-of interest and then cancels the interference attributable to the detected signal-of-interest from the received signal until the last signal-of-interest is detected. The signal quality estimator is configured to compute per-subcarrier signal-to-interference-plus-noise ratios for a plurality of subcarriers allocated to the signal-of-interest; and compute a total signal-to-interference-plus-noise ratio for the subcarriers based on the per-subcarrier signal-to-interference-plus-noise ratios of the subcarriers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 illustrates an exemplary block diagram of a MIMO transmitter.
[0009] FIG. 2 illustrates an exemplary receiver according to one embodiment of the present invention using a maximum likelihood (ML) or near ML detector to jointly detect a signal-of interest with one or more other signals.
[0010] FIG. 3 illustrates an exemplary method implemented by the receiver for computing a signal-to-interference-plus-noise ratio of the signal-of-interest detected using an ML or near-ML detector.
[0011] FIG. 4 illustrates a mapping function for translating a computed signal-to-interference-plus-noise ratio into a desired information rate and modulation scheme.
DETAILED DESCRIPTION
[0012] Referring now to the drawings, FIG. 1 illustrates an exemplary MIMO transmitter 10 for generating SC-FDMA signals. An information bit stream is divided into two or more streams corresponding to the number of transmit antennas. Each bit stream is encoded in a channel encoder 12 (e.g., Turbo encoder) to produce a coded bit stream. The coded bit streams are modulated by modulators 14 (e.g., QAM) to generated time domain modulation symbol streams s n (0), s n (1), . . . , s n (K−1). Each modulated symbol stream is applied to a SC-FDMA transmitter 15 comprising a serial-to-parallel (S/P) converter 16 , a discrete Fourier transform (DFT) unit 18 , an inverse fast Fourier transform (IFFT) unit 20 , a cyclic prefix adder 22 , and a parallel-to-serial (P/S) converter 24 . Serial-to-parallel converter 16 converts a serial stream of time-domain modulated symbols s n (0), s n (1), . . . , s n (K−1) to a parallel substreams. DFT 20 converts the time-domain modulated symbols to frequency-domain symbols S n (0), S n (1), . . . , S n (K−1). As a result, each frequency-domain symbol is a function of all time-domain symbols in the input symbol stream. IFFT 20 applies an inverse Fourier transform to the frequency-domain symbols, cyclic prefix adder 22 adds a cyclic prefix to the IFFT output, and parallel-to-serial converter 24 converts the parallel symbols into a serial SC-FDMA signal stream. In frequency-selective channels, the time-domain symbols cannot be separated, interference-free, through linear equalization and IFFT. In this situation, ML or near-ML detectors that jointly detect the time-domain symbols s n (0), s n (1), . . . , s n (K−1) offer performance improvement. Although FIG. 1 illustrates a separate encoder 12 and modulator 16 for each information bit stream, it will be appreciated that the information bit stream could be encoded and modulated prior to being divided.
[0013] FIG. 2 illustrates an exemplary receiver 100 according to one embodiment of the present invention. The receiver 100 includes front end circuits 110 and a receive signal processor 120 . The front end circuits 110 downconvert the received signal to baseband frequency, amplify and filter the received signal, and convert the received signal to digital form for input to the receive signal processor 120 . The main purpose of the receive signal processor 120 is to demodulate and decode a plurality of signals-of-interest.
[0014] In one embodiment of the invention, the receive signal processor 120 uses a multi-user detection (MUD) to detect a plurality of signals-of-interest. As used herein, the term multi-user includes the case where a single user is transmitting multiple streams, which from the perspective of the receiver, is the same as multiple users. Thus, the signals-of-interest may comprise signals from two or more different users, or multiple signals for a single user, or some combination thereof.
[0015] The exemplary receive signal processor 120 employs successive interference cancellation (SIC) to successively demodulate and decode the signals-of-interest contained in the received signal. The receive signal processor detects the signals-of-interest one at a time. After a signal is detected, the interfering signal can be recreated at the receiver using knowledge of the channel and subtracted from the received signal. This process is repeated successively, for each signal-of-interest, and progressively reduces the interference as each of the signals-of-interest is detected. Typically, the strongest signal is detected first and canceled from the received signal, which mitigates the interference for weaker signals.
[0016] The main functional components of the receive signal processor 120 comprise an interference canceller 122 , channel estimator 124 , impairment covariance estimator 126 , joint detector 128 , decoder 130 , signal generator 132 , and signal quality estimator 134 . The functional components of the receive signal processor 120 may be implemented by one or more microprocessors, hardware, firmware, or a combination thereof.
[0017] The received signal is input to the interference canceller 122 . The interference canceller 122 iteratively subtracts estimates of previously detected signals-of-interest from the received signal to generate a modified received signal for input to the joint detector 128 . During the initial iteration, the received signal is fed unchanged to the joint detector 128 . For each subsequent iteration, the detected signal from the previous iteration is fed back to the signal generator 132 to regenerate an estimate of the interference attributable to the detected signal. The interference estimate is subtracted from the received signal by the interference canceller 122 . This process is repeated until all of the signals-of interest have been detected.
[0018] The channel estimator 124 generates an estimate of the channel from one or more transmit antennas at a transmitting station (not shown) to one or more receive antennas (not shown) using any known channel estimation techniques. Typically, pilot symbols are used in the channel estimation process; however, data symbols could also be used as effective pilot symbols to improve channel estimation. The channel estimate produced from the pilot signal should be scaled appropriately to account for the power difference between pilot symbols and data symbols. The impairment covariance estimator 126 uses the channel estimates from the channel estimator 124 to estimate the covariance of the signal impairments, such as multi-user interference, self interference, other-cell interference, and noise, in the signals-of-interest. A new channel estimate and impairment covariance estimate is generated after each iteration. The channel estimates and impairment covariance estimates are input to the joint detector 128 , which uses the impairment covariance estimates along with the channel estimates to detect one of the signals-of-interest in the received signal. The channel estimates and impairment covariance are also used by the signal generator 134 to generate estimates of the signals-of-interest.
[0019] The joint detector 128 preferably comprises an ML detector or near ML detector, such as a reduced state sequence estimator, SLI detector or AMLD detector. The joint detector 128 jointly processes symbols in each signal-of-interest contained in the received signal and generates received symbol estimates for each signal-of-interest. The received symbol estimates are demodulated to form received bit soft values that are then fed to a decoder 130 . The decoder 130 detects errors that may have occurred during transmission and outputs an estimate of a transmitted information sequence.
[0020] The signal quality estimator 134 estimates the signal-to-interference-plus-noise ratios (SINR) for the signals-of-interest. The SINR estimates may then be used to generate a channel quality indications (CQI), or modulation and coding scheme (MCS) selections. The CQI and/or MCS values may be reported to the transmitting station for link adaptation and/or scheduling. Therefore, reliable estimates of the SINR estimates are needed. Techniques are known for computing reliable SINR estimates for linear minimum means squared error (LMMSE) receivers for uplink in LTE systems. However, there are currently no known techniques for producing reliable SINR estimates for ML or near ML detectors for the uplink in LTE.
[0021] The signal quality estimator 134 according to embodiments of the present invention is able to produce reliable SINR estimates for single input/single output (SISO) and single input/multiple output (SIMO) systems. FIG. 3 illustrates a method 150 according to one exemplary embodiment of the invention for generating SINR estimates for a signal-of-interest transmitted over an OFDM carrier. It is presumed that each signal-of-interest is transmitted from a single transmit antenna to one or more receive antennas. A single transmit antenna may be a single virtual transmit antenna which consists of a number of physical antennas. The signals-of interest can originate from multiple users or a single user. In the example, below, it is presumed that the signals-of-interest are received on multiple receive antenna.
[0022] The signals-of interest are detected successively by an SIC receiver as previously described (block 152 ) The SINR estimator 134 first computes a SINR estimate for each signal-of-interest. To compute SINR for a given signal-of interest, the SINR estimator 134 computes a per-subcarrier SINR estimate for each subcarrier allocated to the signal-of-interest (block 154 ). The SINR estimator then combines the per-subcarrier SINR estimates to obtain the final SINR estimate for the signal-of-interest (block 156 ). The SINR estimates for the signals-of interest can then be used to select a transmission format (MCS value) and/or to compute a CQI (block 158 ).
[0023] In one exemplary embodiment, the per-subcarrier SINR estimate for the nth signal-of-interest, denoted SIR[k] n , is computed according to:
[0000] SINR[ k] n =E s,n H n H [k]R w,n −1 [k]H n [k] Eq. (1)
[0000] where K is the total number of sub-carriers corresponding to the uplink spectrum allocation and k indexes the subcarriers, E s,n is the symbol energy of the nth signal-of interest, H n [k] is the channel response vector collecting the frequency responses of the kth sub-carrier from the corresponding transmit antenna to all M receive antennas, H n H is the Hermetian transpose of the channel response vector, and R w,n [k] is the total impairment covariance at the kth sub-carrier. The channel response vector is given by:
[0000]
H
n
[
k
]
=
[
H
0
n
[
k
]
H
1
n
[
k
]
⋮
H
M
-
1
,
n
[
k
]
]
Eq
.
(
2
)
[0000] The impairment covariance matrix R w,n [k] may be computed according to:
[0000]
R
w
,
n
[
k
]
=
R
w
[
k
]
+
∑
j
=
n
+
1
N
-
1
E
s
,
j
H
j
[
k
]
H
j
H
[
k
]
Eq
.
(
3
)
[0000] where
[0000]
∑
j
=
n
+
1
N
-
1
E
s
,
j
H
j
[
k
]
H
j
H
[
k
]
[0000] is the covariance of the interference from other signals-of-interest that remain in the received signal, and R w,n [k] is the M×M matrix accounting for the noise and other cell interference covariance at the kth sub-carrier. In cases where the noise and other cell interference are uncorrelated across different antennas, R w,n [k] takes the form of a diagonal matrix.
[0024] After the per-subcarrier SINR is obtained, the signal quality estimator 134 computes a total SINR for the signal-of interest based on the per-subcarrier SINR estimates. More specifically, the signal quality estimator 134 computes a per subcarrier capacity C k,n for the subcarriers allocated to the signal-of-interest. The per-subcarrier capacity C[k] n for a given subcarrier k is computed according to:
[0000] C[k] n =log(1+SINR[ k] n ) Eq. (4)
[0000] The base of logarithm in the above capacity computation is 2 or other values. The per-subcarrier capacities C k for the subcarriers allocated to the signal-of-interest are then summed and averaged by the signal quality estimator 134 to compute an average SINR given by:
[0000]
C
AVG
,
n
=
1
K
∑
k
=
0
K
-
1
C
[
k
]
n
Eq
.
(
5
)
[0000] The average capacity C AVG is then used to compute SINR MLD of the signal-of-interest for a ML detector or near ML detector according to:
[0000] SINR MLD,n =exp( C AVG,n )−1 Eq. (6)
[0025] Combining Eqs. 1-6, the SINR MLD for the signal-of-interest is given by:
[0000]
SINR
MLD
,
n
=
exp
(
1
K
∑
k
=
0
K
-
1
log
(
1
+
E
s
,
n
H
n
H
[
k
]
(
R
w
[
k
]
+
∑
j
=
n
+
1
N
-
1
E
s
,
j
H
j
[
k
]
H
j
H
[
k
]
)
-
1
H
n
[
k
]
)
)
-
1
Eq
.
(
7
)
[0000] The exp(x) and log(x) functions in Eq. (7) may, in some embodiments, be replaced by linear approximations or look-up tables.
[0026] As previously described, the SINR MLD may be used to generate a channel quality indication (CQI) and/or MCS (modulation and coding scheme) value to be reported to the transmitting station for link adaptation and/or scheduling. In SU-MIMO system, where the transmissions of the signals-of-interest originate from different users, the MCS/CQI to be reported for each signal-of interest can be obtained from a mapping function given by:
[0000] MCS n =MCSFormat(SINR MLD,n ) Eq. (8)
[0000] FIG. 4 illustrates one exemplary mapping function for translating SINR MLD,n to a target information rate and modulation scheme. If the modulation order is pre-determined, the MCSFormat function takes the information rate corresponding to the modulation order at the calculated SINR MLD,n value. Alternatively, the MCSFormat function takes the highest information rate amongst the permitted modulation orders. That is, the modulation order is also dynamically and implicitly selected by the MCSFormat function. Such MCSFormat function can also be implemented as a look-up table stored in a retrievable storage/memory medium. More generally, to conserve MCS/CQI signaling bandwidth requirements, the MCSFormat transformation involves quantization of the SINR, which results in a look-up table with small number of entries.
[0027] Further adjustments can be applied to SINR MLD,n for link adaptation purposes. As non-limiting examples, such adjustments are typically applied to account for different quality of service requirements, losses induced by implementation imperfection, and channel quality variations within scheduling latency. To account for such variations, the mapping function for translating the SINR MLD,n to MCS/CQI becomes:
[0000] MCS n =MCSFormat(SINR MLD,n −δ n ) Eq. (9)
[0000] where δ n is the said SINR adjustment for the nth signal-of-interest. In one embodiment, the adjustments are dependent on the processing order in the SIC receiver to mitigate effects of potential error propagation. Decoding failures or errors in the signals that are processed earlier can increase the interference levels for the signals that are processed later. To minimize such error cases, it is advantageous to increase the error and interference resilience of the signals to be processed early in the SIC receiver by assigning decreasing values of the SINR adjustments (δ 0 ≧δ 1 ≧ . . . ≧δ N−1 ).
[0028] For SU-MIMO systems, the N signals-of-interest are transmitted by a single user from an equal number of transmit antennas using K subcarriers. Depending on the system specifications, the N MCS/CQI values may be translated into N MCS/CQI values, one MCS/CQI value or L MCS/CQI values (with L<N).
[0029] In the first case (separate MCS/CQI values), the N MCS/CQI values can be obtained by applying the MCSFormat mapping function to the N SINR MLD,n values individually as shown in Eq. (9) or Eq. (10).
[0030] In the second case (only one MCS/CQI value), the SINR MLD,n values may be combined into a single MCS/CQI value according to:
[0000] MCS=JointMCSFormat(SINR MLD,0 , . . . ,SINR MLD,N−1 ) Eq. (10)
[0000] If the modulation order is pre-determined, the JointMCSFormat mapping function takes the information rate corresponding to the modulation order at the calculated SINR MLD,n value. Alternatively, full flexibility to use different modulation orders on different transmit antennas can also be supported. However, to conserve MCS/CQI signaling bandwidth, it may be a good engineering tradeoff to impose a single modulation order on the multiple transmit antennas corresponding to the same MCS/CQI signaling. In this case, the JointMCSFormat mapping function takes the highest information rate amongst the permitted modulation orders. That is, the modulation order is also dynamically and implicitly selected by the JointMCSFormat mapping function.
[0031] One non-limiting example of the JointMCSFormat mapping function has the following form:
[0000]
M
C
S
=
JointMCSFormat
(
SINR
MLD
,
0
,
…
,
SINR
MLD
,
N
-
1
)
=
Summary
(
MCSFormat
(
SINR
MLD
,
0
)
,
…
,
MCSFormat
(
SINR
MLD
,
N
-
1
)
)
.
Eq
.
(
11
)
[0000] That is, the individual SINR MLD,n values are first translated using the MCSFormat mapping function disclosed in the above. The translated values are then summarized into a single MCS/CQI value. If the modulation order is pre-determined, the individual MCSFormat mapping function takes the information rate corresponding to the modulation order at the calculated SINR MLD,n value. Alternatively, full flexibility to use different modulation orders on different transmit antennas can also be supported.
[0032] In the third case (L<N MCS/CQI values), a single modulation order can be imposed on the multiple transmit antennas corresponding to the same MCS/CQI to conserve signaling bandwidth. The required translation procedure is as follows. A temporary modulation order is selected from the range of permitted modulation orders. The individual MCSFormat mapping functions are then evaluated based on the temporary modulation order selection. The final modulation order decision is set to the temporary modulation order that gives rise to the highest MCS/CQI level.
[0033] One non-limiting exemplary Summary function takes the form of weighting all translated values:
[0000]
M
C
S
=
JointMCSFormat
(
SINR
MLD
,
0
,
…
,
SINR
MLD
,
N
-
1
)
=
∑
n
=
0
N
-
1
w
n
×
MCSFormat
(
SINR
MLD
,
n
)
,
Eq
.
(
12
)
[0000] where w n is the weight for the nth antenna. One exemplary weight assignment is that w n =1/N for all n=0, . . . , N−1. Alternatively, uneven weighting may be applied per system setup requirements. To conserve signaling bandwidth, it may be necessary to quantize the summarized value:
[0000]
M
C
S
=
JointMCSFormat
(
SINR
MLD
,
0
,
…
,
SINR
MLD
,
N
-
1
)
=
Quantization
(
∑
n
=
0
N
-
1
w
n
×
MCSFormat
(
SINR
MLD
,
n
)
)
.
Eq
.
(
13
)
[0034] In the third case, the system specifications require the N SINR MLD,n values to be summarized into L MCS/CQI values (with L<N). This is accomplished by breaking the N SINR MLD,n values into L subsets. The SINR values in each subset are then combined using a JointMCSFormat translation function disclosed in the above. In combination with the teaching of minimizing error propagation, L different (and generally decreasing) SINR adjustments should be assigned for the L different SINR subsets:
[0000]
M
C
S
l
=
Quantization
(
∑
k
=
n
l
n
l
+
1
-
1
w
n
×
MCSFormat
(
SINR
MLD
,
k
-
δ
l
)
)
,
Eq
.
(
14
)
[0000] where {SINR MLD,n l , . . . , SINR MLD,n l+1 −1 } is the list of SINR for the lth subset and δ 0 ≧δ 1 ≧ . . . ≧δ L−1 .
[0035] In some embodiments, the MU-SIMO and SU-MIMO approaches can be combined to provide flexible balance of system and user throughput. Let M denote the total number of receive antennas at the base station and K denote the total number of sub-carriers allocated to the transmissions. Let U denote the total number of user terminals scheduled to transmit simultaneously on the allocated sub-carriers. For, the uth UE transmits its signal with Nu antennas. As mentioned before, we only consider cases where the total number of uplink transmit antennas from all simultaneous scheduled UEs does not exceed to the total number of receive antennas:
[0036] The present invention provides a method and apparatus for easily computing the CQI for SLI, AMLD, or other ML, or near ML, receivers in the uplink of LTE. Thus, the present invention allows the base station to schedule a user to use a transmission rate that is more accurately reflecting the receiver capability, taking full advantage of advanced receiver performance.
[0037] The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the scope and essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein. | A receive signal processor jointly detects two or more symbols in a signal-of-interest in the presence of one or more other MIMO signals. The signal-to-interference-plus-noise ratio for each signal-of-interest is determined by computing per-subcarrier signal-to-interference-plus-noise ratios for a plurality of subcarriers allocated to the signals-of-interest, and computing a total signal-to-interference-plus-noise ratio for the subcarriers based on the per-subcarrier signal-to-interference-plus-noise ratios of the subcarriers. A controller determines one or more transmission formats for uplink transmissions based on the signal-to-interference-plus-noise ratios. The process of computing per-subcarrier signal-to-interference-plus-noise ratio reflects the amount of MIMO interference already cancelled or still remaining in the signal arriving at the joint detector. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to an interlocking waney edge glue system for utilizing waney lumber to produce composite wood products and thereby reduce waste. In particular, the present invention relates to profiled wood articles made from waney lumber and a system for using the profiled wood articles to manufacture composite edge-glued wood products.
BACKGROUND OF THE INVENTION
[0002] The production of standard lumber inevitably results in waste in the form of waney lumber, or boards or pieces of lumber that, instead of being cut square, show the original curve of the log from which they are cut. Due to the curvature and irregular shape of waney lumber, it is difficult to use in the manufacture of wood products. Its low cost, on the other hand, makes it a potentially useful raw material. Many composite wood products are made by gluing and pressing pieces of lumber together. To carry out such a lamination of lumber, each of the pieces of lumber used must have complementary surfaces that provide a good joining surface. As waney lumber has irregular surfaces that do not facilitate lamination, waney lumber must be further processed to provide complementary uniform surfaces before it can be used to produce composite wood products. A typical approach to utilizing waney lumber has been to simply saw off the waney portion of the board. Such an approach results in a great deal of waste of waney fiber.
[0003] As forests are a precious resource, and as there is a need to conserve forests, the minimization of waste is desirable. Consequently, there is a need in the art for a means of utilizing waney lumber to obtain composite wood products with a minimum of waste.
[0004] Previously disclosed methods of utilizing waney lumber have further deficiencies and limitations that negatively impact the efficiency of making composite products from waney lumber, or the durability of such products. Known methods often do not produce strong joints between adjacent pieces of waney lumber due to insufficient contact area for the joint, and non-uniform contact between profiled edges. Profiling refers to the reshaping of waney lumber to remove the irregular rounded surfaces. In addition, the edge profiles of the prior art are such that complex pressing machinery (e.g. two-dimensional presses) is required. Such presses significantly increase the cost of the final composite product due to the cost and complexity of the press itself, a more complex manufacturing process and the relatively low throughput.
[0005] Key to producing waney wood composite products that are commercially feasible is that the products must be durable as well as easy to produce. Ideally, the profiled edges between adjacent pieces of lumber are shaped such that they provide a strong joint, permit the use of conventional pressing equipment, and allow a standard manufacturing process.
[0006] U.S. Pat. No. 5,870,876, issued to Deiter, discloses a composite wood product made from a plurality of identical profiled pieces of lumber having identical and complementary profiled edges. However, the profile used in Deiter is such that a two dimensional press is required because the profiled edges do not interlock in a manner that prevents lateral movement of adjacent pieces of profiled lumber. Therefore, if a one dimensional press is used, the glue lines perpendicular to the press plates don't receive any pressure and the profiled pieces of lumber are likely to shift during the pressing process.
[0007] Accordingly, it is an object of the present invention to provide a composite wood product and means for the manufacture thereof, that makes efficient use of waney lumber (i.e. cost effective use resulting in a minimum of fiber waste) and that requires only a conventional one dimensional edge glue press during the manufacturing process.
SUMMARY OF THE INVENTION
[0008] A composite edge-glued wood product, comprising profiled pieces of lumber bonded and pressed together. The profiled pieces of lumber are made from waney lumber, which has been profiled such that the waney edges thereof have been removed to reveal profiled edges. The profiled edges each have at least one protrusion and one indentation, and each of the profiled edges extends from the top surface and the bottom surface of the respective profiled piece of lumber.
[0009] The profiled pieces of lumber are arranged side by side in parallel relation and adjacent profiled pieces are inverted with respect to one another such that the top and bottom surfaces of the composite wood product are formed by alternating top and bottom surfaces of the profiled pieces.
[0010] Each of the profiled edges is complementary to and engageable with adjacent profiled edges on adjacent and inverted profiled pieces of lumber such that adjacent profiled pieces of lumber are in close-fitting and interlocking engagement with one another by mutual interlocking engagement of their respective profiled edges.
[0011] The interlocking engagement of the profiled pieces of lumber prevents lateral movement of adjacent profiled pieces of lumber relative to one another when the composite wood product is pressed. During manufacture, adjacent profiled edges are bonded to one another by adhesive, and the composite wood product is pressed in one dimension in a manner operative to force adjacent profiled edges against one another. Accordingly, in the preferred embodiments the profiled edges do not have portions or faces parallel to the top and bottom surfaces because such portions or faces would not receive pressure when the profiled pieces of lumber are pressed in a conventional edge gluing press. In addition, depending on the precise configuration of the profiled edges in question, it may be more difficult to apply glue to such portions or faces.
[0012] The present invention additionally contemplates a method of making the composite wood product. The first step in the method is to provide elongated pieces of waney lumber which are then profiled by removing the waney edges thereof to reveal profiled pieces of lumber having profiled edges. Each of the profiled edges has at least one protrusion and one indentation, and each of the profiled edges extends from the top to the bottom surface of a respective profiled piece of lumber. Adhesive is then applied to the profiled edges, and the profiled pieces of lumber are arranged side by side in parallel relation such that adjacent profiled pieces of lumber are inverted with respect to one another and such that adjacent profiled edges come into close-fitting interlocking engagement. The profiled pieces are arranged such the top and bottom surfaces of the composite wood product are formed by alternating top and bottom surfaces of the profiled pieces of lumber.
[0013] The close fitting interlocking engagement the adjacent profiled pieces is operative to prevent lateral movement of adjacent profiled pieces of lumber relative to one another.
[0014] The interlocked profiled pieces of lumber are then pressed together in one dimension such that the adjacent profiled edges are forced against one another.
[0015] The invention makes use of waney lumber, which is a presently underutilized and readily available raw material, to make composite wood products. Further, the invention makes use of waney fiber in an economical way. The use of a one-dimensional edge glue press takes advantage of inexpensive conventional technology.
[0016] The invention also enables the manufacture of edge-glued composite products from material with wane only on one side as well as square-edge material.
[0017] Other objects and advantages of the invention will become clear from the following detailed description of the preferred embodiment, which is presented by way of illustration only and without limiting the scope of the invention to the details thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Further features and advantages will be apparent from the following Detailed Description of the Invention, given by way of example, of a preferred embodiment taken in conjunction with the accompanying drawings, wherein:
[0019] FIG. 1 is a cross section of waney lumber having two waney edges;
[0020] FIG. 2 is a cross section of profiled lumber having both edges profiled;
[0021] FIG. 3 is a cross section of a composite wood product formed from profiled lumber;
[0022] FIG. 4 is a cross section of a prior art composite wood product formed by combining prior art profiled lumber;
[0023] FIG. 5 is a cross section of a prior art composite wood product formed using square-edged lumber;
[0024] FIG. 6 is a cross section of a prior art composite wood product formed by combining prior art profiled lumber;
[0025] FIG. 7 is a cross section of waney lumber having one waney edge;
[0026] FIG. 8 is a cross section of profiled lumber having one profiled edge;
[0027] FIG. 9 is a cross section of a composite wood product formed by combining profiled lumber having one profiled edge;
[0028] FIG. 10 is a cross section of a log showing waney lumber produced as a byproduct when producing standard lumber;
[0029] FIGS. 11 to 14 are illustrations of various additional profiled edges; and
[0030] FIG. 15 is a flow chart of the method of manufacturing the composite wood products of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0031] FIGS. 1 and 2 illustrate an elongated piece of waney lumber 10 , having an upper surface 60 , a lower surface 62 , and waney edges 16 , and a profiled piece of lumber 12 made therefrom. The elongated piece of waney lumber 10 and the profiled piece of lumber 12 are shown in cross-section (i.e. the longitudinal axes of the piece of waney lumber 10 and the profiled piece of lumber 12 extend perpendicularly out of the page). Waney lumber usually results as a byproduct from the production of standard lumber as a consequence of the curvature of the tree from which the lumber is produced. By way of example, the elongated piece of waney lumber 10 is illustrated as being a waney byproduct from the production of standard 2×6 lumber; the dotted outline 14 indicates the shape that a standard 2×6 piece would have.
[0032] The rounded, irregular surface of the waney edge 16 makes the elongated piece of waney lumber 10 unsuitable for use in the manufacture of composite wood products because it is not possible to achieve a strong and uniform bond between the waney edge 16 and other components of composite wood products. Cutting off the entire waney portion to produce a lumber product with a rectangular cross section would result in much waste. It is desirable to utilize a maximum of the waney fiber for purposes of manufacturing composite wood products.
[0033] FIG. 2 shows a profiled piece of lumber 12 obtained by profiling the elongated piece of waney lumber 10 of FIG. 1 . The dotted line in FIG. 2 indicates the waney edge 16 of the original waney lumber 10 . The process of profiling amounts to the removal of the waney portions 30 from the original waney lumber 10 to form profiled edges 18 .
[0034] Profiled lumber 12 is shaped such that the profiled edge 18 has protrusions 28 and indentations 38 , and so as to be complementary to a profiled edge of an adjacent piece of profiled lumber. Referring to FIG. 3 , two or more pieces of profiled lumber 12 may be combined to produce a composite wood product 20 . Adjacent pieces of profiled lumber 12 are inverted with respect to one another such that the top and bottom surfaces of the composite wood product 20 are comprised of alternating top 60 and bottom 62 surfaces of the profiled pieces of lumber 12 .
[0035] FIG. 4 shows prior art (see U.S. Pat. No. 5,870,876) in which a profiled piece of lumber 70 has a profiled edge 72 , which profiled edge 72 contacts a similar profiled edge 72 of an adjacent profiled piece 70 to form a composite wood product 74 . During the manufacture of the prior art composite wood product 74 , the profiled pieces 70 must be pressed simultaneously in two dimensions. Pressing in the first dimension is achieved by applying equal and opposite forces to the upper 78 and lower surfaces 80 such that the horizontal portions 82 of the profiled edges 72 of adjacent profiled pieces 70 are forced against one another. The second dimension is orthogonal to the first and pressing in the second dimension is achieved by applying equal and opposite forces to the left and right sides of the composite product 74 such that the vertical portions 76 of adjacent ones of the profiled pieces 70 are forced against one another. If pressing is performed in only one dimension the. profiled pieces 70 may shift relative to one another along either the vertical portions 76 or horizontal portions 82 , whichever are perpendicular to the pressing force and the glue line (i.e. vertical portions 76 or horizontal portions 82 ) parallel to the pressing force will not receive any pressure at all, creating no bond.
[0036] Referring to FIGS. 2 and 3 , profiled edges 18 are shaped such that protrusions 28 and indentations 38 of each piece of profiled lumber 12 engage the protrusions 28 and indentations 38 of an adjacent piece of profiled lumber 12 when two or more pieces of profiled lumber 12 are joined together to form composite wood product 20 . During the manufacturing process the profiled pieces of lumber 12 are pressed together along one dimension (in contrast with the prior art as discussed above in relation to FIG. 4 ). The pressing step is achieved by applying equal and opposite forces to either side of the composite wood product 20 along an axis parallel to the upper and lower surfaces 60 , 62 such that the profiled edges 18 of adjacent profiled pieces of lumber 12 are forced together (i.e. the profiled pieces 12 are pressed together from the left and right as viewed in FIG. 3 ). The mutual engagement of the protrusions 28 and indentations 38 during the pressing process prevents movement of the profiled pieces of lumber 12 relative to one another in a direction perpendicular to the upper and lower surfaces 60 , 62 and to the longitudinal axes of the profiled pieces of lumber 12 , and allows for pressure being applied to all glue lines while being pressed. In other words, protrusions 28 and indentations 38 are so shaped as to make a composite wood product 20 resistant to lateral movement at joint 64 during the pressing process and to create a strong durable glue line.
[0037] Preferably, the profiled edges 18 do not have portions or faces parallel to the upper and lower surfaces 60 , 62 because such portions or faces would not receive pressure when the pieces of lumber 12 are pressed in a conventional edge gluing press, and because, depending on the precise configuration of the profiled edges 18 in question, it may be more difficult to apply glue to such portions or faces.
[0038] The profiled pieces of lumber 12 in FIG. 3 have identical profiled edges 18 . A less complex and more efficient process of manufacturing composite wood products results from this as the same milling head may be used on each piece of waney lumber 10 , and, furthermore, on each waney edge 16 of each piece of waney lumber 10 . In addition, any two adjacent profiled pieces of lumber 12 selected from a plurality of such pieces 12 can be fit together.
[0039] As a consequence of the shape of profiled edges 18 , pieces of profiled lumber 12 mate precisely, thereby reducing, if not eliminating, any need for planing the surfaces of composite wood product 20 . As illustrated in FIG. 5 , in the prior art there arises the problem of alignment of the component pieces of lumber 92 as the flat profile does not prevent lateral movement of the pieces of lumber 92 during the process of gluing and pressing. As illustrated in FIG. 6 , a similar problem is encountered in the manufacture of prior art composite wood products. If a one dimensional press is used, the wood products 70 can shift during the pressing step (the adhesive applied between the wood products 70 can act as a lubricant) resulting in a loss of alignment. As a result of such shifting, the integrity of the joints between adjacent pieces of prior art profiled pieces of lumber 70 is compromised, and the surface of the resulting composite product is uneven.
[0040] As stated above, and with reference to FIG. 3 , the present invention makes use of profiled lumber 12 having profiled edges 18 shaped so as to: (a) allow precision mating of adjacent pieces of profiled lumber 12 ; (b) resist lateral movement of adjacent pieces of profiled lumber 12 such that composite products may be made by pressing in only one dimension; and (c) create a strong durable glue line. Adjacent pieces of profiled lumber 12 automatically interlock for a precision fit upon the exertion of pressure from either side in the direction of joint 64 (i.e. pressed in one-dimension so as to force profiled edges 18 of adjacent pieces of profiled lumber 12 together).
[0041] FIGS. 7 to 9 illustrate a piece of waney lumber 24 having one waney edge 16 , a piece of profiled lumber 26 made therefrom having one profiled edge 18 , and a composite wood product 40 made from such profiled pieces of lumber. The square edge 42 of profiled lumber 26 may be joined with square edge 42 of another piece of profiled lumber 26 or standard lumber (having a rectangular cross section) in order to form a composite wood product. FIG. 9 shows a composite wood product 40 made of a plurality of profiled pieces of lumber 26 . The embodiment of FIG. 9 serves to demonstrate that the present invention is compatible with prior art edge gluing systems.
[0042] A further aspect of the present invention is that one single profile is used on all the profiled edges 18 of all the profiled pieces of wood 12 , 26 so that the process of milling waney lumber into profiled lumber, and the process of assembling the profiled lumber into composite wood products is simplified. In order for a single profile to be used on all of the profiled pieces of lumber 12 , 26 , the profile must have a certain degree of symmetry, such that any one profiled edge will mate with an identical profiled edge that is inverted with respect thereto. FIGS. 11 to 19 illustrate several alternative profiles 18 that exhibit such symmetry, while also exhibiting the characteristics of preventing lateral movement of adjacent profiled pieces of lumber and minimizing waste of waney fiber.
[0043] In a preferred embodiment, the choice of profile of the profiled edges 18 is made so as to maximize the utilization of waney lumber through the selection of a profile that most closely follows the original waney edge 16 . In general, waney edges will have a surface that, in cross section, resembles an arc (as illustrated in FIG. 1 ).
[0044] Referring to FIGS. 1, 2 and 11 - 14 , several examples are shown of profiled edges 18 demonstrating the necessary symmetry about line 36 such that, given two pieces of profiled lumber 12 , each having the same profiled edges 18 selected from FIGS. 1, 2 and 11 - 14 , the profiled edges are complementary to one another and interlockingly fit together in a manner that prevents lateral movement of the two profiled pieces of lumber relative to one another.
[0045] In addition, in the preferred embodiment of the invention the configuration of the profiled edges 18 is selected such that a maximum of waney fiber is retained (i.e. fiber waste is minimized).
[0046] The profile chosen for the profiled edge 18 of any given embodiment of the present invention can be chosen according to several criteria such as, for example, the degree of wane, the quality of the lumber, the machinery and/or tools available, the application for which the composite wood product is intended to be used, etc.
[0047] The present invention additionally contemplates a method for manufacturing composite wood products, as is shown in FIG. 15 . The process of fabricating composite wood products begins with conventional lumber, running it through a moisture meter 140 and sorting it in the chop line 150 into different lumber sorts 160 . Wet lumber 170 is kiln dried 180 when required. The sorting 150 produces both square-edged lumber 192 and waney lumber 194 . Although the present invention is particularly advantageous in that it maximizes utilization of waney lumber, it is applicable to square-edged lumber as well. As discussed above, waney lumber is lumber cut from near the outside of the log and one or two edges are rounded off and irregular. At step 200 , the shorter lumber pieces may be finger jointed to achieve the requisite length.
[0048] After finger jointing 200 the lumber is profiled 210 to provide profiled edges 18 , (see FIGS. 2, 3 and 11 - 14 ). The profiling step 210 also makes it possible to utilize waney lumber that previously was not useable in composite construction. The profiling step 210 removes the waney portions of the waney lumber or square edges in the case of square edged lumber.
[0049] The profiled lumber is then trimmed, laid up, glued and pressed 220 together to form a composite wood product. This step involves the application of adhesive in the interfaces joints 64 between the profiled edges of adjacent profiled pieces of lumber 12 , 26 (see FIGS. 2, 3 , 8 and 9 ). Once the adhesive has been applied the profiled pieces of lumber 12 , 26 are processed 220 in a conventional edge-gluing press. No pressing is required in a second dimension because the profiling of the lumber prevents lateral movement of the lumber during the pressing process. Once the glue has set, the product is finished 230 and packaged for shipping 240 or further processed 250 .
[0050] Preferably, the adhesive or bonding material is applied to substantially all surfaces of profiled edge 18 . The present invention provides an additional advantage over the prior art method of producing composite wood products, which method utilizes square-edged lumber (whether originally waney lumber or not), as the profiled edge 18 has a greater surface area than the square edge for adhesion, and thereby allows for a stronger joint between adjacent profiled pieces of lumber 12 , 26 .
[0051] Composite wood products formed from the profiled lumber provide significant improvements in resistance to shearing and impact forces and improved load bearing capacity. Composite wood products further avoid many of the complex reinforcing requirements of the prior art. In addition, the significant resistance to shearing and impact forces achieved in the composite wood products above permits the use of wood pieces from old growth and stagnant growth timber as well as younger generation timber for a much broader application of use in the lumber industry.
[0052] Accordingly, while this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to this description. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention. | A composite edge-glued wood product, comprising profiled pieces of lumber bonded and pressed together. The profiled pieces of lumber are made from waney lumber, which has been profiled such that the waney edges thereof have been removed to reveal profiled edges. The profiled edges each have at least one protrusion and one indentation. Interlocking engagement of the profiled pieces of lumber prevents lateral movement of adjacent profiled pieces of lumber relative to one another when the composite wood product is pressed. The invention makes use of waney lumber to make composite edge-glued wood products. The use of a standard edge glue press takes advantage of inexpensive conventional technology. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to a clamping mechanism or device and more particularly to clamping device for use with the installation of trusses for building, particularly roof trusses for peaked roofs of houses and the like.
BACKGROUND OF THE INVENTION
[0002] Truss systems are essential for supporting roofs on buildings, and peaked roofs are particularly difficult to put into place by one's self. However, labour costs encourage people to attempt to install truss systems with reduced manpower, perhaps increasing thereby a safety issue.
[0003] Canadian Patent File No. 2,364,466, laid open Jun. 3, 2002, of Lin et al., illustrates a truss spacer and brace which provides apparatus for spacing structural members in particular roof trusses, during construction and for permanently bracing the same structural member. The device includes a top truss tab and flanges spaced to define a slot for the truss member.
[0004] U.S. Pat. No. 5,884,411 granted Mar. 23, 1999 of Raber discloses a truss alignment apparatus which includes a T-shaped beam member which includes a top planar portion and a bottom planar portion extending perpendicular to the top portion. The bottom planar portion includes a plurality of beam-reception notches positioned longitudinally to it. There is also an alignment level incorporated in the apparatus.
[0005] U.S. Pat. No. 5,580,036 granted Dec. 3, 1996 to Browning (see also Canadian Patent File No. 2,215,954) relates to a method and apparatus for remotely securing and spacing trusses and other building frame assemblies. The apparatus is primarily comprised of a spacer having a first truss connector and a second truss connector. A pull down arrangement (example by a rope) is used to remotely engage the apparatus with a truss. In use, the apparatus is attached to a first building member which is then positioned with the apparatus attached. The apparatus is then remotely pulled down and secured to a second, adjacent building member that has just been moved into position.
[0006] Although the Browning device potentially permits a reduced number of people to assemble a truss system, it is a somewhat complicated device and requires some means such as a rope to activate the apparatus in order to secure the apparatus to a second adjacent building member. Ropes and the like around construction sites may be hazardous at times.
[0007] It would be desirable to provide a more simple and economical clamp apparatus which is operative essentially automatically once attached to a first building member to capture and temporarily secure a second adjacent building member or truss swung into place, until the second member can be finally secured with appropriate spacer members and the like.
SUMMARY OF THE INVENTION
[0008] The present invention in one aspect relates to a truss clamp device and more particularly in one aspect to a truss clamp for connection with a second clamp, wherein the truss clamp comprises means for adjustable connection with the second clamp and has a fixed member to which a rotatable member, having first and second ends, is pivotally connected intermediate the ends thereof. The rotatable member is rotatable between a first position wherein the first end is in confronting relation with a portion of the fixed member and a second position wherein the second end is in confronting relation with the portion of the fixed member. The rotatable member is selectively maintained in at least the second position and preferably in both positions. A spring mechanism in co-operation with the fixed member and the rotatable member maintains the rotatable member in both positions by an “over center” configuration relative to the pivot connection.
[0009] Preferably, the device includes a releasable lock mechanism to lock the rotatable member in the second position and the rotatable member is configured to maintain the lock mechanism out of lock position when it is in the first position and to automatically release the lock mechanism when it moves to the second position. A stop mechanism on the rotatable member cooperates with the fixed member to limit rotation of the rotatable member in the second position under the bias of the spring means.
[0010] The invention also provides a truss clamp assembly comprising a first clamp and a second clamp, the first and second clamps each having bar means adjustably connected whereby spacing between the clamps may be selectively adjusted. The first clamp has releasable clamp means adapted to be clamped to a fixed truss and the second clamp has a fixed member and a rotatable member, the rotatable member having first and second ends. The rotatable member is pivotally connected to the fixed member intermediate the ends of the rotatable member and is rotatable between a first position wherein the first end is in confronting relation with a portion of the fixed member and a second position wherein the second end is in confronting relation with the portion of the fixed member. Means selectively maintain the rotatable member in the first position and the second position, the maintaining means comprising spring means configured in relation to the pivotal connection to provide an over center action to selectively maintain the member in the first position or second position. An auxiliary clamp is provided for adjustable connection with one of the bar means and is adapted to be temporarily connected to a truss intermediate trusses to which the first and second clamps are associated in use of the clamp assembly.
[0011] The invention further comprises a method of installing a second truss in constructing a roof structure, wherein at least one first truss is already secured in place, each truss having a base and peak roof portion, the method including the steps of:
providing a truss clamp comprising a first clamp, a second clamp, and means adjustably connecting the clamps in spaced relation, the spacing between the clamps being selected in accordance with desired spacing between the trusses when installed, the second clamp including a trip clamp mechanism; detachably connecting the first clamp to a part of the peak roof portion of the secured first truss such that the second clamp extends in a direction where the second truss is to be located; locating the base of the second truss generally parallel with the base of the first secured truss and moving the peak roof portion of the second truss into a position whereby the second truss peak roof portion engages with and trips the trip clamp mechanism of the second clamp so that the peak roof portion of the second truss is releasably held in position by the second clamp; and, permanently securing the second truss in place by other means and removing the truss clamp for selected reuse.
[0016] Other aspects and features of the invention will become evident from reviewing the detailed description of preferred embodiments in conjunction with the drawings, as set forth herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The nature and mode of operation of the present invention will now be more fully described in the following detailed description of the invention taken with the accompanying drawing figures, in which:
[0018] FIG. 1 is a schematic view of a roof truss assembly wherein two trusses are in secured position and a third is readied for being swung into place.
[0019] FIG. 2 is a side view of a preferred embodiment of the clamp apparatus according to the invention with a first portion of the clamp device, clamped to an already secured truss while the next adjacent truss to be secured is being swung into place toward a second portion of the clamp devices.
[0020] FIG. 3 is a side view of part of the clamp device of FIG. 2 showing further movement of the adjacent truss into place for securement.
[0021] FIG. 4 is a side view of part of the clamp device of FIG. 2 showing the adjacent truss temporarily secured into place with the clamp device.
[0022] FIG. 5 is a side perspective view from the top of the clamp device of FIGS. 3 and 4 in its ready position as shown in FIG. 2 .
[0023] FIG. 6 is a side view similar to FIG. 2 of another, more preferred, embodiment of the invention with the clamp section in a set position for being tripped.
[0024] FIG. 7 is a view similar to FIG. 3 , of the embodiment of FIG. 6 , with the clamp section tripped and holding a truss.
[0025] FIG. 8 is a side view of the clamp section of FIG. 6 looking in the direction of arrow 8 of FIG. 6 .
[0026] FIG. 9 is a side view of the clamping section of FIG. 7 looking in the direction of arrow 9 of FIG. 7 .
[0027] FIG. 10 is a cross sectional view of a truss and the bar of a bar clamp illustrating an adjustable auxiliary clamp device when the inventive clamp device is configured to span or extend over an already secured truss.
DETAILED DESCRIPTION OF THE INVENTION
[0028] At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical structural elements of the invention. While the present invention is described with respect to what is presently considered to be the preferred embodiments, it is understood that the invention is not limited to the disclosed embodiments.
[0029] Turning to the drawings, FIG. 1 schematically illustrates a section of a building 10 having walls 12 , 14 and 16 with walls 12 , 14 having at least upper surfaces 20 , 22 respectively to which trusses of assembly 24 are secured. Illustrated are first and second trusses 30 , 32 secured to the surfaces 20 , 22 and showing a brace 34 between the first truss 30 and second truss 32 . It will be appreciated by those skilled in the art that additional braces between the trusses 30 , 32 could be used. A third truss 36 is shown having ends lying on surfaces 20 , 22 and with the central section 38 of truss 36 supported by a cross beam 40 or the like, whether such beam 40 is temporary or permanently secured to walls 14 and 16 . Other wall support members can be present, but have been omitted for the sake of simplicity.
[0030] With truss 32 (as well as truss 30 ) secured in position, and appropriately braced, at least one clamp device 50 in accordance with the invention is secured at one end thereof to the truss 32 adjacent the top thereof as shown in FIG. 1 . Preferably at least one second like clamp device 50 (not shown) would be installed on the other side of peak 52 of truss 32 . Clamp device 50 is more particularly shown in FIGS. 2-5 .
[0031] In FIG. 2 , clamp device 50 is shown to include an adjustable, first clamp section 52 and a second, pivotal clamp section 54 . First clamp section 52 is basically a known form of a bar clamp device and has fixed jaw 56 and slidable jaw 58 with fixed handle portion 60 and squeezeable handle portion 62 . First clamp section 52 , as a bar clamp, operates in known fashion and release button 64 allows the jaws 56 , 58 to separate, the jaw 58 sliding on bar 64 relative to jaw 56 . In use, first clamp section 52 is secured to truss 32 .
[0032] As further shown in FIG. 2 , second clamp section 54 includes bar 70 and has L-shaped clamp member 72 welded or otherwise secured to bar 70 . L-shaped clamp member 72 comprises leg portion 74 and arm portion 76 . Spaced from leg portion 74 is rotatable clamp member 78 which is pivotally secured to arm portion 76 at pivot 80 . Rotatable clamp member 78 has opposite side surfaces 82 , 84 and has pins or posts 86 and 88 extending from opposite side surfaces 82 and 84 respectively. Pin or post 86 on the far side surface 82 , as seen in FIG. 2 acts as a stop means relative to arm portion 76 to limit the rotation of rotatable clamp member 78 in the counterclockwise direction as shown in FIG. 2 . Pin or post 88 on the near side surface 84 extends outwardly so as to enable securement of one end of coil spring 92 . The other end of coil spring 92 is secured to another pin or post 96 secured to L-shaped clamp member 72 .
[0033] Pivotal clamp member 78 is configured to have a straight section 100 and a bulbous section 102 .
[0034] It will be appreciated from reviewing FIGS. 2-4 that as truss 34 shown in dotted lines is swung into place in the direction of arrow 104 , its upper end 106 contacting bulbous section 102 of clamp member 78 . Continued forced movement of upper truss end 106 in the direction of the arrow 104 forces and causes clamp member 78 to rotate in a clockwise direction as seen in FIG. 3 . Continued movement of truss 34 causes truss side 108 to contact clamp leg portion 74 at which time rotatable clamp member 78 has rotated so that flat edge 110 contacts the side of upper end 106 of truss 34 . During the rotation of rotatable clamp member 78 , coil spring 92 has moved over pivot 80 , that is, an “over center” action is provided by the configuration of the spring 92 and pivot 80 when member 78 is rotated. Rotatable clamp member edge 110 is thus caused to contact and hold the upper portion 106 of truss 34 tightly against fixed clamp member 72 under the bias of spring 92 . In summary, the rotatable clamp member 78 with the over center spring/pivot configuration, is caused to trip from a first non-clamping position to a second clamping position.
[0035] Clamp sections 52 and 54 are adjustably associated via block 120 which is secured to bar 70 , such as by welding. Block 120 has means provided in the illustrated embodiment, as best seen in FIG. 5 , to secure bar 64 thereto, such means comprising a groove 122 in block 120 and cover plate 124 secured by fastening screws 126 . FIG. 5 is a perspective view from the bottom of the clamp section 54 as seen in FIG. 2 . This construction allows relative movement between the bars 64 , 70 when screws 126 are loosened. Accordingly, the spacing between the first clamp section 52 and the second clamp section 54 can be adjusted to match the desired spacing between adjacent trusses.
[0036] When truss 34 is clamped in place, it is then secured by normal bracing (not shown) and clamp device 50 can be removed by releasing clamp section 52 from truss 32 and pulling both sections 52 and 54 upwardly from trusses 32 and 34 respectfully. Clamp device 50 is then reused for the next truss to be swung into place (not shown), clamp section 52 being then clamped to the just installed truss 34 .
[0037] As shown in dotted lines in FIGS. 2, 3 and 4 , and full lines in FIG. 5 , pivoted clamp portion has block 130 which enlarges the contact area between the edge 110 of rotatable clamp member 78 and the side of truss upper end 106 . A similar block 132 ( FIG. 5 ) can be made part of member 74 for similar reasons.
[0038] It will be appreciated that any number of clamp devices or apparatuses 50 can be used and reused in erecting a truss assembly. If final securement of a truss by normal means is not performed until several trusses have been located in place, then the clamp device 50 can be left in place until final securement is made. The spring force of spring 92 is made such as to firmly hold and temporarily secure each truss swung into place. Nevertheless, the clamp section 54 may be easily pulled from a truss 34 swung into place and otherwise normally secured.
[0039] Turning to FIGS. 6 to 9 , a further preferred embodiment of the invention and more particularly, pivotal clamp section 54 a is illustrated. Parts which are essentially the same to the embodiment of FIGS. 2 to 5 have the same reference numerals and other parts or elements which have been modified, but are similar, are designated with an “a”.
[0040] As seen in FIGS. 8 and 9 , arm portion 76 a of L-shaped clamp member 72 a is sized and configured to have groove 122 a therethrough, groove 122 a configured to accept bar 64 of clamp section 52 . Arm portion 76 a has cover plate 124 a which is detachable and releasably secured to arm member 76 a by screw fasteners 126 a , or the like. The construction incorporates the adjustability between clamp sections 52 and 54 a into the arm portion 76 a of the L-shaped clamp member 74 .
[0041] Turning to FIGS. 6 and 7 , the main difference between this embodiment and that of FIGS. 2 to 5 is in the enlarged bulbous portion 102 a which is generally semi-circular. Further, there is a lock mechanism 140 which locks the rotatable clamp member 78 a from accidentally opening while other forms of securement of the truss are being effected. Lock mechanism 140 comprises block or housing 142 which is secured to and effectively part of arm portion 76 a . Block 142 has a through bore 144 within which pin 146 reciprocates. Pin 146 is secured to spring arm 148 and spring arm 148 is secured at one end 150 to block 142 by fastener means 152 . The other end 154 of spring arm 148 extends beyond the block 142 and can be manually activated or manipulated.
[0042] As will be appreciated from FIGS. 6 and 8 , when pivotal section 54 a is in position to be tripped by a truss 34 , the bulbous portion 102 a covers and maintains pin in a retracted position ( FIG. 8 ) whereas when truss 34 has tripped rotatable clamp member 78 a , the bias of spring arm 148 forces pin 146 to extend outwardly so that pin 146 , in contacting part 158 of bulbous portion 102 a , prevents rotatable clamp member 78 a from rotating back in a counterclockwise direction as seen in FIG. 7 .
[0043] Arm spring end 154 can be manually manipulated (downwardly as seen in FIGS. 8 and 9 ) to retract pin 142 and allow the rotatable clamp member to be returned to the position shown in FIG. 6 .
[0044] The clamp device 50 has clamp sections 52 and 54 ( 54 a ) spacially adjustable relative to each other to enable the distance between them to be selected. Although two or any number of clamp devices 50 can be used in assembling trusses of a building, additional support during assembly can be provided and, the invention further comprehends a clamp device 50 wherein the selected space between clamp sections 52 and 54 ( 54 a ) is twice the desired spacing between adjacent trusses. In this embodiment there is preferably and adjustable auxiliary clamp element 160 shown in FIG. 10 .
[0045] FIG. 10 is a cross-sectional view of the bar 64 of clamp section 52 and of a truss 34 . Auxiliary clamp element 160 has a U-shaped portion 162 with thumb screw 164 so that device 160 can be slidably fixed or secured to bar 64 at a desired location. Auxiliary clamp element 160 has extension 166 with a prong or projection 168 . In use, clamp section 52 with an extended bar 64 can be secured to fixed truss 30 for example, and auxiliary clamp element 160 adjusted so that projection 168 is aligned with fixed truss 32 and clamp section 54 ( 54 a ) is in place to secure truss 36 when it is swung up into position. Prong or projection 168 is tapped by a hammer into the upper frame member of the intermediate truss which further steadies the clamp device 50 when the next adjacent truss 36 is swung into position. The added stability to the clamp device 50 with the increased span and auxiliary clamp element 160 is significant. Such an extended version of the clamp device is shown in dotted lines in FIG. 1 as 50 ′ although it would normally in use be higher up and closer to the ridge section of the truss.
[0046] Although applicants have described preferred embodiments of the invention, variations and modifications will be apparent to those skilled in the art and applicants do not limit the scope of the invention solely to such preferred embodiments, but include variations and modifications which fall within the scope of the appended claims. | A truss clamp for connection with a second clamp when installing truss assemblies includes a mechanism for adjustably connecting the two clamps in spaced relation. The truss clamp includes a fixed member and a rotatable member, the rotatable member having first and second ends and being pivotally connected to the fixed member intermediate the ends of the rotatable member and being rotatable between a first position wherein the first end is in confronting relation with a portion of the fixed member and a second position wherein the second end is in confronting relation with the portion of the fixed member. A holding mechanism may be disposed over a center spring action mechanism, for selectively maintaining the rotatable member in at least the second position. A method of installing trusses using a truss clamp is also disclosed. | 8 |
RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. Pat. No. 09/652,228, filed Aug. 29, 2000, entitled “Fish Pond Filter System.”
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to the field of ornamental landscaping and, in particular, to a filter system designed to efficiently remove solid wastes and biologically decompose suspended wastes in fish ponds.
[0004] 2. Description of the Related Art
[0005] Fish ponds accumulate and generate a variety of contaminants and waste products that must be removed and treated to maintain the attractive appearance of the fish pond and the health of the fish living therein. The exposed water surface tends to retain air blown dust, dirt, and leaves and other plant matter that falls in. The fish themselves produce excrement that is a solid waste material and a source of unwanted biological activity. The temperate closed water ecosystem that is essential for the fish is also an excellent environment for the growth of algae and other undesirable living organisms. Fish food that remains uneaten by the fish can contaminate the pond and nourish undesirable living organisms. The closed system of a fish pond also favors chemical processes such as ammonia production that, if left unchecked, can rapidly degrade the appearance of the fish pond and its ability to support healthy fish.
[0006] The accepted method of maintaining the health and appearance of a fish pond is to separate the solid waste from the water, react the chemicals to either remove them or make them non-damaging, and treat the water to kill undesirable organisms. Two methods have typically been used to do this. One is to filter out the solid wastes and dispose of them, treat the water with a variety of chemicals and/or high intensity UV light to kill biological undesirables, and react the undesirable chemicals. The other is to employ a filter medium that retains the solid waste and decomposes the waste with biologically active bacteria that live on the filter medium. This method would also typically require treatment with high intensity UV light or chemicals to eliminate the undesirable biological and chemical constituents, although the chemical and/or UV light treatment regimen may not be as rigorous as with simple filtering.
[0007] A variety of methods and apparatuses are known to remove solid material from a liquid, however a major concern with removal of solid waste is what to do with the waste once it is separated from the water. Separation devices that depend on density differences, such as a centrifuge, are not effective in fish pond applications because many of the waste solids are approximately the same density as the water they are in, therefore the effective devices typically employ some type of filtering to trap the solids. The two major ways to handle the separated waste are to discard the waste trapped in a filter along with the filter or to backwash the filter and direct the waste stream elsewhere. A disadvantage of removing the waste trapped in a filter along with the filter is that generally these types of filters are a single use filter and thus must be replaced with a new one when the old one is full. It can be appreciated that the labor and cost to perform this replacement would be a drawback to a user for which the fish pond is a decorative and recreational item.
[0008] In order to avoid the cost and inconvenience of changing filter elements, the preferred method of removing trapped waste is to utilize some form of backwashing. Backwashing essentially consists of reversing the direction of water flow in the filter and thereby forcing the waste products out a waste outlet. The filter media does not typically need to be removed and after the backwashing is complete, the filter media is ready to retain more waste. Advantageously, fish ponds are often located adjacent garden areas and the backwashed water contains partially decomposed fish and vegetable waste that makes a beneficial fertilizer in the garden. However, the water discharged in the backwashing procedure is typically a cost to the user and minimizing water discharge is a concern particularly in areas where water is in limited supply.
[0009] The biological reaction process is an advantageous adjunct because the heterotrophic bacteria that perform the reaction are naturally occurring in the pond water. No user action is needed to establish and maintain a colony of beneficial bacteria other than to provide a place for them to live. Also, biological reaction converts many of the undesirable chemicals to non-harmful forms and thus reduces the need for chemical treatment. The chemicals used for chemical treatment are relatively expensive and many users would understandably like to minimize their handling of chemicals. The heterotrophic bacteria are not suited to live freely suspended in water and require a surface on which to grow. This has typically been done on the filter medium which generally consists of a gravel bed or filter mat.
[0010] A disadvantage to biological reaction is the relatively large amount of reactor volume and time typically required for the process to occur. With traditional gravel or filter mats, a biological filter/reactor can require a filter/reactor volume of up to 40% of the volume of the pond itself. It can be appreciated that such a large filter/reactor assembly is expensive to purchase and install and can negatively affect the aesthetics of the fish pond system. In addition a traditional biological reaction filter design can require several weeks to several months for the bacteria to substantially decompose the deposited wastes. The time required for waste decomposition must be such that the waste is decomposed at at least the rate it is deposited. Otherwise the filter becomes overloaded and can no longer protect the health and appearance of the pond.
[0011] As the bacteria live on a solid surface, there is an upper limit to how many can live on a given area, i.e. their population density. The time and volume required for a biological reaction filter can be dramatically reduced by providing increased area for the bacteria to live on and thereby increasing the number of bacteria resident in the filter reactor. The optimal filter media provides the highest surface area-to-volume ratio possible. With gravel or fibrous mats, the bacteria live on the surface and from a consideration of the shape of a piece of gravel or fiber it can be seen that other configurations of filter media would provide greater surface area for a given volume of media.
[0012] One type of filter media on the market with a higher surface area to volume ratio than gravel or fibers is the ACE-1400 media. The ACE-1400 media is made of plastic tubing with a specific gravity slightly less than one, which is cut to be slightly longer than the diameter of the tubing. The ACE-1400 is approximately 3.5 mm in diameter and 5 mm long. It can be appreciated that a hollow tube can support bacteria on both the outer and the inner surface. The size and shape of the hollow tube media is such that it has 15 to 20 times the surface area of an equivalent volume of gravel or fiber matting.
[0013] The ACE-1400 type media is typically placed in a container and pond water is pumped through the container so as to flow generally upwards. Since the ACE-1400 media has a specific gravity slightly less than one, the media floats towards the top of the container. Since the pond water is generally flowing upwards in the container, waterborne waste material is trapped throughout the media, but predominantly towards the bottom. The naturally occurring bacteria reside on and within the ACE-1400 media and digest the waste that lodges within the media.
[0014] The container is also provided with valves and piping to backwash the container periodically by reversing the water flow direction downwards and then out of the container. The backwashing causes the media to swirl and tumble, thereby releasing trapped solids. A properly sized container filled with the appropriate amount of media would generally require backwashing once a week. The container is provided with screens so that the media does not escape the container during either backwashing or normal operation. The filter system is also provided with screens to restrict larger solids such as leaves, twigs, and fish from being pumped into the filter container.
[0015] It can be appreciated that the more media that is in a filter system, the more surface area is provided for heterotrophic bacteria growth. However, because the ACE-1400 filter media is of a uniform size and shape, movement of the water tends to cause the filter elements to stack in a uniform manner, particularly when the container is filled to a relatively high percentage of capacity. The stacking process tends to create channels or voids in the filter media. These channels provide paths for the water to flow along without requiring that the water pass through the filter media. It can be appreciated that the filter is not effective in trapping and decomposing wastes if the water is not passing through the media. The stirring motion of backwashing randomizes the orientation of the filter elements, however they tend to re-stack and create channels in a relatively short time after the system returns to normal filtering flow.
[0016] While the ACE-1400 filter media and system offer advantages over traditional disposable filters and chemical treatment or gravel or fiber matting filter systems employing biological waste decomposition, it can be appreciated that improvements upon this system would be an advantage to the users of fish ponds. It can be appreciated that there is an ongoing need for a filter system for fish ponds that employs naturally occurring bacterial metabolization of wastes to remove these wastes from fish ponds. The system should be economical to purchase and install. The filter media should be reusable and provide the maximum surface area to volume ratio possible to support a maximum number of beneficial bacteria and to enable the system to be sized as small as possible and decompose the solid wastes as rapidly as possible. The system should require minimal use of chemicals to treat the water. The backwashing method should be as efficient as possible to remove the maximum amount of waste and extend the periods between backwashes, while avoiding channeling effects and corresponding failure to filter.
SUMMARY OF THE INVENTION
[0017] The aforementioned needs are satisfied by the fish pond filter system of the present invention, which in one aspect is a novel filter media with an increased surface area-to-volume ratio. In another aspect, the invention is a filter reactor with a more efficient backwashing system.
[0018] The extruded bio-tube filter media of the present invention is formed from extruded ABS plastic with a specific gravity slightly greater than one. The extruded bio-tube is generally tubular with internal and external ribbing. The addition of the internal and external ribbing provides approximately twice the surface area for the bio-tube of the present invention compared to a similar sized simple tube media, such as the ACE-1400. In addition, the internal ribbing provides smaller interior passages and allows the media to trap proportionally smaller waste material.
[0019] An additional advantageous feature of the present invention is that the media is provided in several different sizes. Also, the present invention is sized so as to be generally 1.3 times as long as it is in diameter. The differing sizes and the shape of the media of the present invention inhibit uniform stacking of the media material. Since the media cannot readily stack together in a uniform fashion, channeling of the material is also inhibited.
[0020] In another aspect of the invention, an efficient backwashing system is provided. The system includes jets adapted to create a vortex within the filter media container during the backwashing operation. The vortex created more efficiently dislodges accumulated waste material and directs the dislodged waste and carrier water out a waste pipe. The vortex created within the fish pond filter system of the present invention more completely cleans the filter media in a shorter time and requires less water to do so. Thus, the fish pond filter system saves time and money. These and other objects and advantages of the present invention will become more fully apparent from the following description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1 is an end view of a typical bio-tube of the present invention;
[0022] [0022]FIG. 2 is a side view of a typical bio-tube of the present invention;
[0023] [0023]FIG. 3 shows end and side views of three different sizes of bio-tubes of the present invention and their relative sizes;
[0024] [0024]FIG. 4 is an assembled, perspective view of the internal plumbing of a fish pond filter container assembly;
[0025] [0025]FIG. 5 is a close-up perspective view of the backwash jets and intake pipe assemblies of a fish pond filter system;
[0026] [0026]FIG. 6 is an exploded, cutaway, perspective view of the filter mode of the fish pond filter system;
[0027] [0027]FIG. 7 is an exploded, cutaway, perspective view of the backwash mode of the fish pond filter system;
[0028] [0028]FIG. 8 is a top view of a valve body and valve handle of the present invention showing the positions of the different operational modes of the valve body and filter system;
[0029] [0029]FIG. 9 is a side view of the assembled fish pond filter system; and
[0030] [0030]FIG. 10 shows a typical installation of the fish pond filter system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0031] Reference will now be made to the drawings, wherein like numerals refer to like parts throughout. A fish pond filter system 100 draws water from a fish pond 300 , filters and treats the water to remove waste 304 , and returns the water to the fish pond 300 as shown in FIG. 10. The fish pond 300 of this embodiment is an open air, closed-system container of water. The fish pond 300 can be outside or placed within a building or other enclosed structure. The fish pond 300 includes a plurality of fish 302 . Fish 302 shall herein be understood to include fish, crawdads, mud puppies, frogs, turtles, shrimps, or any other vertebrate or invertebrate animals suited to live at least partially in an aquatic environment. The fish 302 generate waste 304 , which is at least in part at least semi-solid biological waste material. Waste 304 shall be herein understood to also include other material that finds its way into the fish pond 300 such as leaves, other vegetable matter, dirt, or insects. The fish pond filter system 100 also includes naturally occurring heterotrophic bacteria 310 . The heterotrophic bacteria 310 feed on the waste 304 typically found in a fish pond 300 and remove the waste 304 from the fish pond 300 in a manner that will be described in greater detail below. The fish pond filter system 100 comprises a pre-filter 306 as shown in FIG. 10 which is positioned and adapted to screen out larger waste 304 particles which are approximately larger than ⅛″ in a well known manner.
[0032] The fish pond filter system 100 comprises bio-tube 102 filter media as shown in FIGS. 1 and 2. The bio-tubes 102 provide a surface to support the growth of heterotrophic bacteria 310 in a manner which is well known in the art and will be better appreciated following a more detailed description of the structure of the bio-tubes 102 and the fish pond filter system 100 . The bio-tubes 102 also retain and subsequently release water-borne solid waste 304 materials which the fish pond filter system 100 passes over the bio-tubes 102 in a manner that will be described in greater detail below. The bio-tubes 102 , of this embodiment, are extruded from ABS plastic in a well known manner. The bio-tubes 102 are provided with a plurality of integral structures formed at the same time and which will be described in greater detail below. The bio-tubes 102 of this embodiment have a finished specific gravity slightly greater than one so as to be slightly non-buoyant in water.
[0033] The bio-tubes 102 structure comprises a ring wall 104 . The ring wall 104 , of this embodiment, is made of ABS plastic and is generally an elongate, hollow, open-ended cylinder approximately 0.300″ outside diameter, 0.250″ inner diameter, and 0.390″ in length. The ring wall 104 has a wall thickness of approximately 0.025″ and provides a growth surface for bacteria in a manner that will be described in greater detail below. The ring wall 104 has an inner surface 106 and an outer surface 110 coaxial with and opposite the inner surface 106 .
[0034] The structure of the bio-tubes 102 further comprises external ribs 112 . The external ribs 112 are made of the same ABS plastic material as the bio-tubes 102 and are generally elongate rectangles of approximately 0.018″×0.035″×0.390″. The external ribs 112 are extruded with the bio-tubes 102 such that a first side of the external ribs 112 is adjacent and materially continuous with the outer surface 110 of the ring wall 104 . The external ribs 112 are positioned such that the long axis of the external ribs 112 (0.390″) is coaxial with the long axis of the bio-tube 102 . In this embodiment, 18 external ribs 112 extend radially outward from the outer surface 110 of the ring wall 104 and are approximately equally spaced about the circumference of the ring wall 104 which in this embodiment is approximately every 20° of angle. The external ribs 112 provide additional surface area to support the growth of heterotrophic bacteria 310 .
[0035] The structure of the bio-tubes 102 also comprises divider walls 114 . In this embodiment, the divider walls 114 are three elongate rectangles approximately 0.018″×0.125″×0.390″ and are made from the same ABS plastic as the bio-tubes 104 . The divider walls 114 have a first edge 116 along a long edge (0.390″) and a second edge 120 opposite the first edge 116 . The divider walls 114 are positioned such that the first edges 116 of the divider walls 114 are adjacent and materially continuous with the inner surface 106 of the ring wall 104 and the second edge 120 of each divider wall 114 is adjacent and materially continuous with the second edge 120 of each of the other divider walls 114 . The divider walls 114 are further positioned so as to be approximately equally spaced radially outwards from the common second edges 120 , which in this embodiment is 120° of angle. The divider 114 walls also support growth of heterotrophic bacteria 310 .
[0036] It should be appreciated that the ring wall 104 , externals ribs 112 , and divider walls 114 are all structures of the bio-tube 102 and, in the preferred embodiment, are extruded at the same time and from the same ABS material. The bio-tube 102 with the structures described has a surface area available for bacterial 310 growth that is approximately twice the surface area of a simple hollow, open-ended cylinder of similar dimensions, but without the external ribs 112 and the divider walls 114 . It should be appreciated that the overall shape of the bio-tube 102 and the number, shape, and placement of the external ribs 112 and divider walls 114 can be varied by one skilled in the art from the configurations described in this preferred embodiment without detracting from the spirit of the disclosed invention.
[0037] The bio-tubes 102 also comprise a plurality of internal passages 122 . The internal passages 122 are the openings within the bio-tubes 102 defined by two adjacent divider walls 114 and the included arc of the inner surface 106 of the ring wall 104 . The inner passages 122 provide a restricted opening for the passage of water and block and hold solid waste 304 material that is larger than the dimensions of the inner passage 122 . In this embodiment, the inner passages 122 will block solid objects that are generally larger than 0.100″ in at least two orthogonal dimensions. The bio-tubes 102 with internal passages 122 block solid objects that are approximately one-third as large as simple hollow cylinders of comparable size.
[0038] [0038]FIG. 3 shows one embodiment of the present invention with three different sizes of bio-tubes 102 . The bio-tubes 102 as shown are generally cylinders and in this embodiment are approximately 0.180″ diameter by 0.234″ long, 0.240″ in diameter by 0.312″ long, and 0.300″ in diameter by 0.390″ long. The different sizes of bio-tubes 102 inhibits uniform stacking of the bio-tubes 102 during use in a manner which will be described in greater detail below. It should be appreciated that alternative shapes, sizes, and number of different sizes and/or shapes of bio-tubes 102 could be employed without detracting from the spirit of the present invention.
[0039] The fish pond filter system 100 also comprises a water flow controller 124 as shown in FIG. 4. The water flow controller 124 comprises a valve body 130 . The valve body 130 is provided with internal structures to control water flow in a manner well understood by those skilled in the art. The water flow controller 124 also comprises a valve handle 126 , which is an elongate member, approximately 8″ in major dimension and made of a plastic material. A first end 128 of the valve handle 126 is rotatably affixed to a top end 154 of the valve body 130 such that rotation of the valve handle 126 induces the valve body 130 to freely permit or restrict water flow through an inlet pipe 132 , an outlet pipe 134 , a waste pipe 136 , and/or a stand pipe 146 all exiting from the valve body 130 in response to the positioning of the valve handle 126 .
[0040] The inlet pipe 132 , outlet pipe 134 , waste pipe 136 , and stand pipe 146 of this embodiment are elongate members, generally open cylinders in profile, and made of a PVC plastic material. The inlet pipe 132 receives untreated water from the fish pond 300 . The outlet pipe 134 directs water which has been treated and filtered by the fish pond filter system 100 in a manner which will be described in greater detail below back to the fish pond 300 . The waste pipe 136 directs water, which may contain waste material 304 , out of the fish pond filter system 100 . The stand pipe 146 directs water flow to and from a backwash jet assembly 170 and intake tube assembly 172 in a manner which will be described in greater detail below.
[0041] The water flow controller 124 also comprises a pressure gauge/sight glass 140 . A first end 141 of the pressure gauge/sight glass 140 is provided with standard “¼” NPT and is therewith threaded into the valve body 130 in a well known manner. The pressure gauge/sight glass 140 is adapted to provide a visual indication of the water pressure within the valve body 130 in a well known manner. The pressure gauge/sight glass 140 is also adapted to provide a visual indication of the presence of water within the valve body 130 . The water pressure indicated by and the visual condition of the water seen in the pressure gauge/sight glass 140 serve as indicia for an operator to control the operation of the fish pond filter system 100 in a manner which will be described in greater detail below.
[0042] The water flow controller 124 also comprises an attachment flange 142 . The attachment flange 142 is generally circular and approximately 7″ in diameter. The attachment flange 142 is made of a plastic material and is adapted to attach the water flow controller 124 to a container 202 , as shown in FIG. 9, in a manner that will be described in greater detail below.
[0043] The water flow controller 124 also comprises a media screen 144 . The media screen 144 is generally a cylinder, open on a first end 150 , closed on a second end 152 and approximately 6″ in diameter and 4″ high. The media screen 144 is made of a plastic material and is provided with a plurality of openings 148 . The openings 148 are generally rectangular, through-going holes in the media screen 144 sized so as to block passage of the bio-tubes 102 through the media screen 144 yet to readily allow the passage of liquid water. The media screen 144 has a second end 152 opposite the first end 150 . A circular opening 160 is provided in the center of the second end 152 of the filter screen 144 . The opening 160 is sized to fit closely around the outer diameter of the stand pipe 146 , which, in this embodiment, is approximately 1 {fraction (1/2)}″ in diameter.
[0044] The first end 150 of the media screen 144 is placed adjacent a bottom end 156 of the valve body 130 opposite the top end 154 . The media screen 144 is positioned such that the opening 160 is aligned with the center of the bottom end 156 of the valve body 130 . The media screen 144 is attached to the bottom end 156 of the valve body 130 with a plurality of screws in a well known manner. A first end 164 of the stand pipe 146 is positioned through the opening 160 in the media screen 144 and further into contact with the valve body 130 so as to securely attach to the valve body 130 and the media screen 144 in a friction fit in a well known manner.
[0045] A second end 166 of the stand pipe 146 is connected to the backwash jet assembly 170 and the intake tube assembly 172 as shown in FIG. 4 and in a close-up view in FIG. 5. The backwash jet assembly 170 of this embodiment comprises a manifold 174 . The manifold 174 is made of a PVC plastic material and is adapted to contain and direct water flow in a manner which will be described in greater detail below. The manifold 174 includes 12 ports 176 . The ports 176 are adapted to direct water flow and are part of and made of the same material as the manifold 174 . The ports 176 are generally circular structures of the manifold 174 which extend radially outward and are arranged in three levels 184 a - c . Each level 184 a - c comprises four ports 176 positioned so as to be at the same distance along the major axis of the manifold 174 and to be approximately equally spaced about the circumference of the manifold 174 which is approximately a spacing of 90° of angle apart.
[0046] A top end 180 of the manifold 174 is provided with female threads in a well known manner. The second end 166 of the stand pipe 146 is provided with male threads in a well known manner such that the male threads of the stand pipe 146 mate with the female threads of the manifold 174 . The top end 180 of the manifold 174 and the second end 166 of the stand pipe 146 are threaded together to achieve the connection between the stand pipe 146 and the backwash jet assembly 170 and the intake pipe assembly 172 . In an alternative embodiment, the threading referred to above need not be present and the manifold 174 and the second end 166 of the stand pipe 146 are joined with a cementing process well known to those skilled in the art.
[0047] A first level 184 a comprising four ports 176 is located approximately 1″ from the top end 180 of the manifold. A t-fitting 186 is connected to each port 176 by a cementing process well known in the art. The t-fittings 186 are plastic pipe structures adapted to direct the flow of water in two substantially orthogonal directions. The t-fittings 186 have three openings 188 for the passage of water. A first opening 188 of each t-fitting 186 is attached to a port 176 of the first level 184 of the manifold 174 with a known cementing process. A second opening 188 of each t-fitting 186 opposite the first opening 188 is connected to a first opening 188 of an elbow 190 with a known cementing process.
[0048] The elbows 190 are plastic pipe structures which are bent at approximately a 90° angle such that water that enters one opening 188 of the elbow exits a second opening 188 in a direction generally 90° from the direction it entered. Jet caps 192 are connected to the second opening 188 of each elbow 190 and to the third opening 188 of each t-fitting 186 using a known cementing process. The jet caps 192 are generally cylindrical, open on one end, and closed on the other end. The jet caps 192 are made of a PVC plastic material and are sized to conform closely to the openings 188 of the t-fittings 186 and the elbows 190 . The jet caps 192 are provided with a jet opening 194 in the closed end. The jet opening 194 is a through-going hole in the jet cap 192 . The jet opening 194 is sized to permit restricted flow of water such that water delivered under pressure to the inside of the jet caps 194 exits at a high velocity through the jet opening 194 .
[0049] The t-fittings 186 and elbows 190 are connected to each other and the manifold 174 such that the jet caps 192 fitted to the t-fittings 186 and the elbows 190 point generally tangentially in a clockwise or counterclockwise direction in the plane of the first level 184 . The t-fittings 186 and elbows 190 are further positioned such that the t-fittings 186 and elbows 190 point at an elevation or declination from the plane of the level 184 a so as to have an elevation or declination of generally between 0° and ±45° from the plane of the level 184 a and thereby the plane of the tangential clockwise or counterclockwise direction. Thus water that is supplied to the t-fittings 186 and elbows 190 is directed out of the jet openings 194 so as to spray out in a generally tangential manner but also in a slightly elevated or declined direction. This serves to create a vortical flow pattern for the backwashing in a manner that will be described in greater detail below.
[0050] The intake tube assembly 172 comprises a second 184 b and third level 184 c located approximately 3″ and 5″ from the top end 180 of the manifold 174 respectively. Each of the second and third levels 184 comprises four ports 176 as previously described with respect to the backwash jet assembly 170 . A first end of an intake tube 196 is attached to each of the ports 176 of the second and third levels 184 of the manifold 174 such that the intake tube assembly 172 comprises eight intake tubes 196 . The intake tubes 196 are generally hollow, cylindrical, elongate members, open on the first end, closed on a second end, and made of a plastic material. The intake tubes 196 are provided with a plurality of intake openings 198 positioned between the first and second ends. The intake openings 198 of this embodiment are through-going slits in the wall of the intake tubes 196 and are sized and positioned to inhibit the passage of the bio-tubes 102 yet to allow minimally impeded passage of liquid water.
[0051] The ports 176 of the second and third levels 184 b and 184 c are positioned such that the intake tubes 196 extend radially outward from the manifold 174 . The ports 176 are further positioned such that the intake tubes 196 of each of the second and third levels 184 are positioned approximately 90° apart about the circumference of the manifold 174 and such that the ports 176 of the second and third levels 184 are positioned approximately 45° from being in alignment with each other. Thus, the intake tubes 196 extend radially outward approximately every 45° about the circumference of the manifold 174 in two levels 184 .
[0052] The fish pond filter system 100 comprises a filter mode 200 as shown in FIG. 6. It should understood that FIG. 6 is an exploded, cutaway perspective view of the fish pond filter system 100 with several components of the fish pond filter system 100 not shown for clarity. FIG. 6 shows an alternative embodiment of the intake tube assembly 172 wherein the intake tubes 196 are positioned so as to extend radially outward from the manifold 174 and so as to be positioned approximately every 45° about the circumference of the manifold 174 in a single level 184 . It should be appreciated by one skilled in the art that the operation of the intake tube assembly 172 as described as follows is substantially similar to the operation of the embodiment of the intake tube assembly 172 previously described.
[0053] The fish pond filter system 100 comprises a container 202 . The container 202 is a hollow, closed structure made of a plastic material. The container 202 is sized and adapted to hold approximately 15 to 150 liters of water. The container 202 is preferably sized to adequately filter the volume of the fish pond 300 in a manner well known to those skilled in the art. The container 202 comprises an opening 204 in a top end 206 . The opening 204 is a generally circular through-going hole in the top end 206 of the container 202 and is approximately 6″ in diameter.
[0054] The water flow controller 124 is partially inserted into the container 202 through the opening 204 such that the stand pipe 146 , the backwash assembly 170 , and the intake tube assembly 172 pass into the interior of the container 202 . An O-ring 210 is placed between the top end 206 of the container 202 and the valve body 130 . The O-ring 210 is generally a toroid approximately 6″ in overall diameter and ¼″ in cross-section and is made of a rubber material. The O-ring 210 inhibits water flow out of the container 202 . The attachment flange 142 is removably attached to the container 202 so as to secure the water flow controller 124 to the container 202 and also so as to hold the O-ring 210 between the container 202 and the water flow controller 124 in compression. The attachment of the attachment flange 142 in this embodiment comprises a clamping procedure well known in the art. In an alternative embodiment, the attachment of the attachment flange 142 comprises a threading procedure or other known methods of removably attaching two assemblies.
[0055] The container 202 also comprises a bottom end 220 opposite the top end 206 . The container 202 also comprises a drain hole 216 adjacent the bottom end 220 . The drain hole 216 is a through-going hole in the container 202 and is provided with internal, female threads. The container also comprises a drain plug 212 and gasket 214 . The drain plug 212 is a brass assembly provided with external, male threads and is sized and threaded so as to be removably threaded into the drain hole 216 so as to hold the gasket 214 between the container 202 and the drain plug 212 in a known manner. The drain plug 212 and gasket 214 inhibit water flow out of the container 202 when they are inserted into the container 202 . Removal of the drain plug 212 and gasket 214 allow water contained within the container 202 to freely flow out of the container 202 .
[0056] A plurality of bio-tubes 102 as previously described are inserted into the container 202 prior to the attachment of the water flow controller 124 previously described so as to fill the container 202 to approximately 50% of capacity. The filtering mode 200 comprises positioning the valve handle 126 to the filter mode 200 position such that water flows freely into the inlet pipe 132 and exits the bottom end 156 of the valve body 130 through the media screen 144 . The water fills the container 202 and exits the container 202 by passing into the intake tube assembly 172 , through the stand pipe 146 , through the valve body 130 , and out the outlet pipe 134 .
[0057] The water entering the fish pond filter system 100 typically is drawn from the fish pond 300 and includes waste 304 . The water enters at the top end 206 of the container 202 and exits adjacent the bottom end 220 . Thus, the water flow is generally downwards. The bio-tubes 102 have a specific gravity slightly greater than unity and thus will tend to sink and rest adjacent the bottom end 220 of the container 202 in the general manner shown in FIG. 6 thereby defining the filtering media for the system 100 . Thus waste 304 contained within the water will pass generally downwards and because of the configuration of the bio-tubes 102 as previously described, the waste 304 will be substantially trapped within and on the upper extent of the bio-tubes 102 . The differing shapes and sizes of the bio-tubes 102 are such that the flow of water within the container 202 and through the bio-tubes 102 induces the bio-tubes 102 to stack in a random manner and to not create channels or voids with the bio-tubes 102 .
[0058] The waste 304 trapped within and on the bio-tubes 102 serves as food material for heterotrophic bacteria 310 . The heterotrophic bacteria 310 are naturally occurring in the fish pond 300 and are carried into the fish pond filter system 100 during use. Over time, the heterotrophic bacteria 310 establish colonies on the surface of and within the bio-tubes 102 . The heterotrophic bacteria 310 metabolize the waste 304 that becomes trapped on and within the bio-tubes 102 and substantially transform the waste 304 into forms which are more aesthetically pleasing in the fish pond 300 and which are not harmful to the health of the fish 302 in a well known manner. For example, the heterotrophic bacteria 310 metabolize nitrogenous compounds such as ammonia. The structures of the bio-tubes 102 as previously described provide a greater surface area for the culturing of the heterotrophic bacteria 310 than other known filtering systems and can support a greater density of heterotrophic bacteria 310 . Thus, the fish pond filter system 100 can process a greater waste 304 load and/or at a faster rate than other comparably sized filtering systems.
[0059] The heterotrophic bacteria 310 are not capable of completely metabolizing all of the waste 304 that typically enters a fish pond 300 and this unreacted waste 304 will accumulate over time. Eventually the amount of unreacted waste 304 will accumulate to the point of restricting flow through the fish pond filter system 100 . This situation is indicated by the water pressure indicated by the pressure gauge/sight glass 140 .
[0060] The fish pond filter system 100 comprises a backwash mode 230 as shown in FIG. 7. The backwash 230 mode is initiated by positioning the valve handle 126 to the backwash 230 mode position. This induces the valve body 130 to direct water flow from the inlet pipe 132 , through the valve body 130 , through the stand pipe 146 , and out through the intake tube assembly 172 and the backwash jet assembly 170 and into the container 202 . The water fills the container 202 if it is not already full and then flows past the media screen 144 , into the valve body 130 , and out the waste pipe 136 .
[0061] The water flow out of the intake tube assembly 172 dislodges waste 304 material that has accumulated on the intake tubes 196 . The water flow out of and the orientation of the backwash jet openings 194 induces a vortical or cyclonic flow 232 pattern within the container 202 . This vortical flow 232 causes the bio-tubes 102 to tumble and swirl, efficiently dislodging waste 304 trapped within or on the bio-tubes 102 . The vortical flow 232 further advantageously sweeps the dislodged waste 304 upwards and tends to cause the waste and its carrier water to segregate from the bio-tubes 102 .
[0062] The backwash 230 mode is conducted for a variable period depending on accumulated waste 304 load that, in this embodiment, is approximately 10 minutes. A user can consult the pressure within the valve body 130 and the visible condition of the water flowing therethrough as indicated by the pressure gauge/sight glass 140 as indicia for terminating the backwash 230 mode.
[0063] Advantageously, the vortical action results in the bio-tubes 102 and the accumulated waste 304 being entrained in the circling water so as to be urged upwards to the level of the waste pipe 136 . The configuration of the backwash ports 176 is such that the water is circulated at a higher velocity in the vortical or cyclonic fashion. The higher velocity of the water results in more of the waste matter 304 being entrained in an upward motion to the level of the waste pipe 136 (FIG. 4) thereby allowing for removal of the waste material 304 . Hence, the cyclonic motion of the water as a result of the placement and configuration of the backwash assembly 170 is better able to urge the waste material 304 into the waste pipe 136 for removal from the system 300 .
[0064] Moreover, the bio-tubes 102 are preferably selected so as to be heavier than the waste material 304 and preferably have a specific gravity selected so that the bio-tubes reside on the bottom 220 of the container 202 in the general manner illustrated in FIG. 6. The waste material 304 generally collects near the upper surface of the layer of bio-tubes 102 comprising the filtration media and is thus located more proximal to the waste pipe 136 . Further, since the bio-tubes 102 are generally heavier than the waste material 304 , when the system 300 is being backwashed, the waste material 304 is generally entrained in the water above the bio-tubes 102 . This allows for flushing of the waste material 304 while reducing the loss of the bio-tubes 102 during the backwashing 230 process.
[0065] Following conclusion of the backwash 230 mode, the valve handle 126 is positioned to select a rinse 240 mode. In the rinse 240 mode, water enters the inlet pipe 132 , passes through the valve body 130 and enters the container 202 through the media screen 144 . The water then exits through the intake tube assembly 172 , the stand pipe 146 and out the waste pipe 136 . The rinse 240 mode settles the bio-tubes 102 in preparation for return to the filtering mode 200 previously described.
[0066] The fish pond filter system 100 further comprises a waste 250 , re-circulate 260 , and closed 270 modes selectable by positioning the valve handle 126 as shown in FIG. 8. The waste 250 mode directs water flow into the inlet pipe 132 , through the valve body 130 and out the waste pipe 136 , bypassing the container 202 and filtering 200 process previously described. The waste 250 mode is used to lower the level of the fish pond 300 without filtering 200 the water. The re-circulate 260 mode directs water into the inlet pipe 132 , through the valve body 130 , and back out the outlet pipe 134 , bypassing the filtering 200 process previously described. The re-circulate 260 mode is used to circulate water in the fish pond 300 without running it through the filtering 200 process previously described. The closed 270 mode blocks water flow into the inlet pipe 132 . The closed 270 mode is used to shut off the fish pond filter system 100 from the rest of the fish pond 300 .
[0067] A side view of a typical installation of the fish pond filter system is shown in FIGS. 9 and 10. The fish pond filter system 100 comprises a pump 320 as shown in FIG. 9. The pump 320 is connected between the fish pond 300 and the inlet pipe 132 and is adapted to pump water from the fish pond 300 to the inlet pipe 132 when supplied with electrical or mechanical power in a well known manner. The pre-filter 306 screens out larger waste 304 particles such as leaves, sticks, or dead fish 302 which are approximately greater than ⅛″ in two dimensions that could damage the pump 320 or plug up the fish pond filter system 100 . In the embodiment shown in FIG. 10, the waste pipe 136 extends to discharge unreacted waste 304 and water in the backwash mode 230 as previously described.
[0068] The fishpond filter system 100 employs naturally occurring heterotrophic bacteria 310 as part of the filter mode 200 . The heterotrophic bacteria 310 metabolizes at least some of the biological waste 304 that is generated and accumulated in the fish pond 300 and thus reduces the chemical treatment that a user of the fish pond filter system 100 needs to employ to maintain the health and appearance of the fish pond 300 . Thus a user of the fish pond filter system 100 reduces the inconvenience and health risks associated with handling chemicals.
[0069] The bio-tubes 102 of the present invention provide a high surface area-to-volume ratio and thus can support an adequately large population of heterotrophic bacteria 310 in a relatively small container 202 . The shape and differing sizes of the bio-tubes 102 of the fish pond filter system 100 are configured to inhibit uniform stacking and channeling during the filter mode 200 . Other known filter media have a relatively low surface area-to-volume ratio and thus require larger, more obtrusive systems or are configured such that they tend to uniformly stack during filtering, which leads to the creation of channels within the filter media, which reduces the effectiveness of a filter system so equipped. By minimizing the size of the container 202 needed to adequately filter a given size of fish pond 300 , the fish pond filter system 100 minimizes the purchase cost, installation time and cost, and aesthetic impact of the fish pond filter system 100 while still efficiently and reliably filtering the fish pond water.
[0070] The fish pond filter system 100 also includes a backwash mode 230 , which creates a vortical flow pattern within the filter media container 202 . The vortical flow efficiently dislodges accumulated waste 304 trapped within the bio-tubes 102 and entrains the waste 304 out of the fish pond filter system 100 . The efficient backwash mode 230 , employing the vortical flow, takes less time to clean the filter media and directs less wastewater out of the system 100 . Thus, the fish pond filter system 100 furthers saves time and money for a user.
[0071] Although the preferred embodiments of the present invention have shown, described and pointed out the fundamental novel features of the invention as applied to those embodiments, it will be understood that various omissions, substitutions and changes in the form of the detail of the device illustrated may be made by those skilled in the art without departing from the spirit of the present invention. Consequently, the scope of the invention should not be limited to the foregoing description but is to be defined by the appended claims. | A system for filtering and treating waste generated or collected in the water of a fish pond. The system includes a pump, pre-filter, piping, a valve assembly, and a filter media container enclosing a plurality of discrete filter media. The filter media are generally hollow, plastic structures with a plurality of external ribs and internal dividing walls. The filter media has a high surface area-to-volume ratio and can support a high volumetric density of naturally occurring heterotrophic bacteria. The heterotrophic bacteria establish colonies on the internal and external surfaces of the filter media and biologically metabolize waste that is trapped on the media. The bacterial metabolization transforms much of the waste to an aesthetically and biologically neutral form thereby reducing the need for chemical treatment of the pond water. The system includes a backwashing mode to agitate and remove unreacted waste from the system and direct the waste stream out of the system, preferably to be used as fertilizer. | 8 |
TECHNICAL FIELD
[0001] The described technology is directed to the field of software applications, and, more particularly, to the field of features for business productivity software applications.
BACKGROUND
[0002] Business meetings are often goal-directed, in that they are called for a specific purpose, and an agenda for conducting a meeting is typically defined that satisfies the meeting's purpose. Historically, it has been common for a planner or presenter to distribute paper copies of the agenda, in some cases together with copies of other supporting materials relating to the agenda.
[0003] More recently, software applications for preparing presentation documents have become generally available. Such applications make it easy for a typical computer user to construct a multiple-page visual presentation that can be projected and advanced throughout the meeting for viewing by all participants. Such presentations can include information that might have otherwise been provided in a written agenda or accompanying supporting documents, or that might not have been provided at all, such as relevant photographs or video clips. Such presentations can also be used for a variety of other visual subject matter not relating to agendas or meetings.
[0004] In general, most presentations generated using such applications are textual outlines of the agenda, which often contain such constructs as lists and outlines. Although it is technically possible to use such applications to generate presentations that present information using more eye-catching business graphics, in practice this capability is seldom used. Failure to use this capability may be explained by the fact that designing such business graphics typically requires both a strong graphical eye and a sense of the different graphical designs which may be used, or by the fact that executing such business graphics typically requires significant drawing talent, time, and patience.
[0005] A few software applications enable a user to insert an empty pregenerated business graphic, which the user can edit to add textual content, or add, delete, or rearrange elements of the graphic. Using this functionality, however, can require significant effort on the part of the user, who must manually map text to each element or subelement of the graphic, type this text in the appropriate place, and modify the structure of the graphic to match the structure desired.
SUMMARY
[0006] A software facility for automatically converting text to business graphics is described. The facility enables a user to select a body of text in a presentation or other document and invoke a “convert to graphic” command that may be invoked in a variety of ways. In response, the facility displays a gallery of different graphic designs that can be used to convert the selected text into a graphic. When the user chooses a graphic design from the gallery, the facility automatically discerns a structure or organization of the selected body of text, and maps this structure onto a graphic template provided for the graphic design to create a graphic corresponding to the selected text. The facility then replaces the selected text with the created graphic. The user may alter the created graphic in a variety of ways, including selecting a new graphic design for the created graphic, or editing the text on which the created graphic is based.
[0007] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a block diagram illustrating an example of a suitable computing system environment or operating environment in which the facility may be implemented.
[0009] FIG. 2 is a user interface diagram showing in an initial display presented by the facility when used in connection with a presentation application.
[0010] FIG. 3 . is a user interface diagram showing a display presented by the facility reflecting textual information entered by the user for inclusion in the presentation.
[0011] FIG. 4 is a user interface diagram showing a display presented by the facility reflecting the user's selection of a convert to graphic button in the user interface.
[0012] FIG. 5 is a user interface diagram showing a display presented by the facility when the user selects a graphic design indication from the graphic design gallery displayed by the facility.
[0013] FIG. 6 is a user interface diagram showing a display presented by the facility when the user selects the more conversion options control.
[0014] FIG. 7 is a user interface diagram showing a display typically presented by the facility when the user invokes a context menu by right-clicking in the client area.
[0015] FIG. 8 is a user interface diagram showing a display typically presented by the facility when the user selects a graphic design indication from a graphic design gallery displayed by the facility when the user selects a convert to graphic entry from a context menu.
[0016] FIG. 9 is a user interface diagram showing a display typically presented by the facility when the user selects the show whole category control.
[0017] FIG. 10 is a user interface diagram showing a display typically presented by the facility showing the result of changing the generated graphic to a newly-selected graphic design.
[0018] FIG. 11 is a user interface diagram showing a display typically presented by the facility when the user edits the textual hierarchy on which the graphic generated by the facility is based.
[0019] FIG. 12 is a user interface diagram showing a display typically presented by the facility when the user further edits the textual hierarchy to change the level of a text line in the hierarchy.
[0020] FIG. 13 is a flow diagram showing steps typically performed by the facility in order to generate and alter a graphic based upon arbitrary text in a document, such as a presentation document.
DETAILED DESCRIPTION
[0021] A software facility for automatically converting text to business graphics (“the facility”) is described. In some embodiments, the facility enables a user to select a body of text in a presentation or other document and invoke a “convert to graphic” command that may be invoked in a variety of ways. The selected text may be defined either explicitly or implicitly based upon user input. In response, in some embodiments, the facility displays a gallery of different graphic designs that can be used to convert the selected text into a graphic. When the user chooses a graphic design from the gallery, the facility automatically discerns a structure or organization of the selected body of text, and maps this structure onto a graphic template provided for the graphic design to create a graphic corresponding to the selected text. The facility then replaces the selected text with the created graphic.
[0022] In some embodiments, the facility continues to display the body of text on which the created graphic is based, such as in a special floating window. The user can edit the displayed body of text, and have the edits reflected in updated versions of the created graphic that are displayed in place of the created graphic. For example, the user may perform edits to the displayed body of text that have the effect of adding a graphical element to the graphic, removing a graphical element from the graphic, promoting or demoting the level of a graphical element of the graphic, or altering the text shown in a graphical element of the graphic.
[0023] In some embodiments, the facility enables the user to choose a new graphic design for an existing graphic. In response, the facility transforms the existing graphic from its prior graphic design to the new graphic design.
[0024] By performing in some or all of the ways described above, the facility enables a user without special skills to easily create and revise professional-quality business graphics in a presentation or other document.
[0025] FIG. 1 is a block diagram illustrating an example of a suitable computing system environment 110 or operating environment in which the facility may be implemented. The computing system environment 110 is only one example of a suitable computing environment and is not intended to suggest any limitation as to the scope of use or functionality of the facility. Neither should the computing system environment 110 be interpreted as having any dependency or requirement relating to any one or a combination of components illustrated in the exemplary operating environment 110 .
[0026] The facility is operational with numerous other general purpose or special purpose computing system environments or configurations. Examples of well-known computing systems, environments, and/or configurations that may be suitable for use with the facility include, but are not limited to, personal computers, server computers, handheld or laptop devices, tablet devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like.
[0027] The facility may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, and so forth that perform particular tasks or implement particular abstract data types. The facility may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in local and/or remote computer storage media including memory storage devices.
[0028] With reference to FIG. 1 , an exemplary system for implementing the facility includes a general purpose computing device in the form of a computer 111 . Components of the computer 111 may include, but are not limited to, a processing unit 120 , a system memory 130 , and a system bus 121 that couples various system components including the system memory 130 to the processing unit 120 . The system bus 121 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures include an Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnect (PCI) bus also known as a Mezzanine bus.
[0029] The computer 111 typically includes a variety of computer-readable media. Computer-readable media can be any available media that can be accessed by the computer 111 and include both volatile and nonvolatile media and removable and nonremovable media. By way of example, and not limitation, computer-readable media may comprise computer storage media and communications media. Computer storage media include volatile and nonvolatile and removable and nonremovable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules, or other data. Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by the computer 111 . Communications media typically embody computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism and include any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communications media include wired media, such as a wired network or direct-wired connection, and wireless media, such as acoustic, RF, infrared, and other wireless media. Combinations of any of the above should also be included within the scope of computer-readable media.
[0030] The system memory 130 includes computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM) 131 and random access memory (RAM) 132 . A basic input/output system (BIOS) 133 , containing the basic routines that help to transfer information between elements within the computer 111 , such as during start-up, is typically stored in ROM 131 . RAM 132 typically contains data and/or program modules that are immediately accessible to and/or presently being operated on by the processing unit 120 . By way of example, and not limitation, FIG. 1 illustrates an operating system 134 , application programs 135 , other program modules 136 , and program data 137 .
[0031] The computer 111 may also include other removable/nonremovable, volatile/nonvolatile computer storage media. By way of example only, FIG. 1 illustrates a hard disk drive 141 that reads from or writes to nonremovable, nonvolatile magnetic media, a magnetic disk drive 151 that reads from or writes to a removable, nonvolatile magnetic disk 152 , and an optical disk drive 155 that reads from or writes to a removable, nonvolatile optical disk 156 , such as a CD-ROM or other optical media. Other removable/nonremovable, volatile/nonvolatile computer storage media that can be used in the exemplary operating environment include, but are not limited to, magnetic tape cassettes, flash memory cards, digital versatile disks, digital video tape, solid state RAM, solid state ROM, and the like. The hard disk drive 141 is typically connected to the system bus 121 through a nonremovable memory interface, such as an interface 140 , and the magnetic disk drive 151 and optical disk drive 155 are typically connected to the system bus 121 by a removable memory interface, such as an interface 150 .
[0032] The drives and their associated computer storage media, discussed above and illustrated in FIG. 1 , provide storage of computer-readable instructions, data structures, program modules, and other data for the computer 111 . In FIG. 1 , for example, the hard disk drive 141 is illustrated as storing an operating system 144 , application programs 145 , other program modules 146 , and program data 147 . Note that these components can either be the same as or different from the operating system 134 , application programs 135 , other program modules 136 , and program data 137 . The operating system 144 , application programs 145 , other program modules 146 , and program data 147 are given different numbers herein to illustrate that, at a minimum, they are different copies. A user may enter commands and information into the computer 111 through input devices such as a tablet or electronic digitizer 164 , a microphone 163 , a keyboard 162 , and a pointing device 161 , commonly referred to as a mouse, trackball, or touch pad. Other input devices not shown in FIG. 1 may include a joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit 120 through a user input interface 160 that is coupled to the system bus 121 , but may be connected by other interface and bus structures, such as a parallel port, game port, or a universal serial bus (USB). A monitor 191 or other type of display device is also connected to the system bus 121 via an interface, such as a video interface 190 . The monitor 191 may also be integrated with a touch-screen panel or the like. Note that the monitor 191 and/or touch-screen panel can be physically coupled to a housing in which the computer 111 is incorporated, such as in a tablet-type personal computer. In addition, computing devices such as the computer 111 may also include other peripheral output devices such as speakers 195 and a printer 196 , which may be connected through an output peripheral interface 194 or the like.
[0033] The computer 111 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 180 . The remote computer 180 may be a personal computer, a server, a router, a network PC, a peer device, or other common network node, and typically includes many or all of the elements described above relative to the computer 111 , although only a memory storage device 181 has been illustrated in FIG. 1 . The logical connections depicted in FIG. 1 include a local area network (LAN) 171 and a wide area network (WAN) 173 , but may also include other networks. Such networking environments are commonplace in offices, enterprisewide computer networks, intranets, and the Internet. For example, in the present facility, the computer 111 may comprise the source machine from which data is being migrated, and the remote computer 180 may comprise the destination machine. Note, however, that source and destination machines need not be connected by a network or any other means, but instead, data may be migrated via any media capable of being written by the source platform and read by the destination platform or platforms.
[0034] When used in a LAN networking environment, the computer 111 is connected to the LAN 171 through a network interface or adapter 170 . When used in a WAN networking environment, the computer 111 typically includes a modem 172 or other means for establishing communications over the WAN 173 , such as the Internet. The modem 172 , which may be internal or external, may be connected to the system bus 121 via the user input interface 160 or other appropriate mechanism. In a networked environment, program modules depicted relative to the computer 111 , or portions thereof, may be stored in the remote memory storage device 181 . By way of example, and not limitation, FIG. 1 illustrates remote application programs 185 as residing on the memory storage device 181 . It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers may be used.
[0035] While various functionalities and data are shown in FIG. 1 as residing on particular computer systems that are arranged in a particular way, those skilled in the art will appreciate that such functionalities and data may be distributed in various other ways across computer systems in different arrangements. While computer systems configured as described above are typically used to support the operation of the facility, one of ordinary skill in the art will appreciate that the facility may be implemented using devices of various types and configurations, and having various components.
[0036] In order to more fully describe the facility, its operation in connection with a specific example is discussed below in connection with FIGS. 2-12 .
[0037] FIG. 2 is a user interface diagram showing in an initial display presented by the facility when used in connection with a presentation application. Those skilled in the art will appreciate that the facility may be used in connection with applications of virtually any type that permit a user to enter or load text. The display 200 includes an application window for the presentation application. The application window includes a client area 210 , into which the user may type text that is to be included in the presentation.
[0038] FIG. 3 is a user interface diagram showing a display presented by the facility reflecting textual information entered by the user for inclusion in the presentation. It can be seen that client area 310 contains text, including a title text line 311 , as well as body text lines 312 - 319 . It can further be seen that the body text has been formed both in an order-in that it is clear which text line comes first, second, etc.-and a hierarchy-in that it can be seen that, for example, text lines 313 and 314 are children of text line 312 . The user can determine the order of the text lines either based upon the order in which they are entered, or by moving an insertion point to the location in the order where the user wants the next-entered text to appear. The user can specify the hierarchy as follows: if the user wants the next text line to be at the same level of the hierarchy as the present text line, the user merely presses the enter key when at the end of the present text line. If the user wants the next text line to be at a lower level than the present text line, the user presses the enter key, then the tab key at the end of the present text line. If the user wants the next text line to be at a higher level of the hierarchy than the present text line, the user presses the enter key, followed by the back-tab key when at the end of the present text line. The user may also change a text line's level in the hierarchy by selecting the line, then selecting either indent button 321 or outdent button 322 . The user may also use a variety of other text editing techniques, such as inserting spaces in front of a text line in order to demote the text line in the hierarchy, or deleting spaces before a text line in order to promote the text line in the hierarchy.
[0039] FIG. 4 is a user interface diagram showing a display presented by the facility reflecting the user's selection of a convert to graphic button in the user interface. Here, the user has placed a text insertion point 499 inside a text container 430 containing text lines 312 - 319 shown in FIG. 3 . When the user selects convert to graphic button 431 in the ribbon area of the application's user interface, the facility displays a gallery 440 of graphic designs into which the text can be converted. In some embodiments, the graphic designs shown in the gallery are limited to a proper subset expected—such as by their designers—to produce the best results from automatic conversion. In some embodiments, the graphic designs shown in the gallery are ordered in a way that reflects a rank among the shown graphic designs of the extent to which they are expected—such as by their designers—to produce good results in the convert to graphic operation. Here, the gallery includes indicators 441 - 447 , each corresponding to a different graphic design and showing an example of the design's appearance. It can be seen that the user has hovered over graphic design indication 441 , causing the facility to display a tool tip containing its name. At this point, the user may either select a graphic design indication from the gallery, or may select control 448 for presenting additional graphic designs that can be used in the conversion.
[0040] FIG. 5 is a user interface diagram showing a display presented by the facility when the user selects a graphic design indication from the graphic design gallery displayed by the facility. In particular, where the user selects graphic design indication 441 after placing insertion point 499 in FIG. 4 , the facility replaces the selected text with a graphic 550 generated from the text contained in text container 430 using the graphic design corresponding to selected graphic design indication 441 . In particular, the graphic has four major elements 551 - 554 , each corresponding to a different one of the four lines of text 312 , 315 , 317 , and 319 at the highest level of the hierarchy. Text from the lower level of the hierarchy is shown in the element corresponding to its parent. For example, lines 313 and 314 appear in element 551 . This mapping from levels of the hierarchy to elements and subelements of the graphic design are configurable aspects of the graphic design. The mappings are also extensible, in that, after the facility is shipped to customers, a graphic design containing a new mapping may be added. The facility further displays a floating window 560 , containing a copy of the textual hierarchy made up of text lines 560 - 568 , which the user may edit in order to modify the generated graphic.
[0041] Where, in FIG. 4 , the user selects the more conversion options control 448 , the facility displays indications of a larger selection of available graphic designs. FIG. 6 is a user interface diagram showing a display presented by the facility when the user selects the more conversion options control. This display includes an extended graphic design gallery 670 which may include graphic designs other than those in the subset determined to be most likely to produce good conversion results. The extended gallery is divided into two panes: a category pane 671 and a graphic design indication pane 676 . When the user selects one of the category indications 672 - 675 displayed in the category pane, the facility displays in the graphic design indication pane indications of a large number of graphic designs belonging to the category. For example, when the user selects indication 672 for the process category, the facility displays a number of indications of process graphic designs, including graphic design indication 677 . The user may select one of these graphic design indications, then select an OK control 678 to select the corresponding graphic design. The user may select a cancel control 679 to dismiss the extended gallery.
[0042] Rather than using a button as shown in FIG. 4 to issue a convert to graphic command, in some embodiments, the user can use a context menu to issue a convert to graphic command. FIG. 7 is a user interface diagram showing a display typically presented by the facility when the user invokes a context menu by right-clicking in the client area. The context menu 730 includes a variety of controls, including a variety of formatting buttons and menu entries, including a menu entry 731 for the convert to graphic command. When the user selects menu item 731 , the facility displays graphic design gallery 740 , containing indications of various graphic designs available for the conversion process including indication 741 . The gallery further includes a more conversion options control 748 that the user may select in order to display an extended gallery containing indications for a larger number of available graphic designs.
[0043] If the user selects indication 741 , then the facility proceeds to generate a graphic based on the text hierarchy using the graphic design corresponding to graphic design indication 741 . FIG. 8 is a user interface diagram showing a display typically presented by the facility when the user selects a graphic design indication from a graphic design gallery displayed by the facility when the user selects a convert to graphic entry from a context menu. The presentation document 810 similar to the one shown in FIG. 5 , including a substituted graphic 850 similar to substituted graphic 550 . In addition, the facility displays a variety of controls relating to the conversion operation. A layout portion of the ribbon 880 includes a limited gallery of graphic design indications, such as indications 841 - 843 . The user may select one of these to change the graphic design used for the graphic produced by the conversion operation, or may use scroll controls 882 - 883 to scroll through the indications of the available graphic designs displayed in positions 841 - 843 . The user may also select a show all control 881 to display a complete gallery of graphic design indications as shown in FIG. 6 , or select a show whole category control 884 to display a gallery of graphic design indications from the same graphic design category as currently-selected graphic design 841 . The ribbon area also includes a construction section 885 containing controls for modifying the graphic, and a quick style section 886 for applying various coloring, shading, and effects styles to the generated graphic.
[0044] FIG. 9 is a user interface diagram showing a display typically presented by the facility when the user selects the show whole category control. The display includes a larger gallery 940 of graphic design indications, including graphic design indication 949 . The user can select any of these graphic design indications to change the graphic generated by the conversion operation to the new graphic design.
[0045] FIG. 10 is a user interface diagram showing a display typically presented by the facility showing the result of changing the generated graphic to a newly-selected graphic design. The display is similar to that shown in FIG. 5 , in that the document area 1010 contains a graphic and a floating window 1060 contains the text from which the graphic was generated. The graphic 1050 , however, is generated in accordance with the graphic design having indication 949 shown in FIG. 9 selected by the user. Like the graphic shown in FIG. 5 , it has a major element 1051 - 1054 for each of the highest-level text lines in the hierarchy, as well as the lower-level text lines shown in connection with the major element for the highest-level text line to which they correspond.
[0046] In addition to using the controls discussed above in connection with FIG. 8 to alter the graphic generated by the facility, in some embodiments, the user may also edit the textual hierarchy on which the graphic is based. FIG. 11 is a user interface diagram showing a display typically presented by the facility when the user edits the textual hierarchy on which the graphic generated by the facility is based. It can be seen that, in response to the user typing new text line 1170 in textual hierarchy 1160 , the user has added a new major element 1155 to the graphic, which contains text 1120 corresponding to new line 1170 .
[0047] FIG. 12 is a user interface diagram showing a display typically presented by the facility when the user further edits the textual hierarchy to change the level of a text line in the hierarchy. By comparing FIG. 12 to FIG. 11 , it can be seen that the user has changed the level of text line 1170 from the highest level to the lower level, making text line 1270 a child of text line 1269 . In response, the facility has removed major element 1155 from the graphic 1150 and added the contents of line 1270 as text 1220 subordinate to major element 1254 .
[0048] From the foregoing it can be seen that the user can take advantage of the facility to automatically generate graphics based upon hierarchical text, choosing a graphic design for the generated graphic and later changing the graphic design to re-generate the generated graphic; as well as change the hierarchical text in order to change the generated graphic.
[0049] FIG. 13 is a flow diagram showing steps typically performed by the facility in order to generate and alter a graphic based upon arbitrary text in a document, such as a presentation document. In step 1301 , the facility receives user input selecting text in a document and selecting a convert to graphic command. For example, the user input may do this as shown in FIG. 4 or FIG. 7 . In some embodiments, the received user input selects text by highlighting a particular section of text, or particular text container objects (such as shapes) or portions thereof. In some embodiments, the received user input selects text by positioning a text insertion point at a particular location within the text, or by scrolling a window in which the text is displayed to a particular location in the text. In various embodiments, the facility permits the user to issue a convert to graphic command using a variety of other user interface techniques, such as selecting an item from a pull-down menu or typing a hotkey or a control-key sequence. In some embodiments, the facility automatically invokes the convert to graphic command in response to indirect indications that the user may be trying to create a graphic.
[0050] In step 1302 , the facility displays a gallery, or “menu” of graphic designs that are available to use to generate the graphic, such as gallery 440 shown in FIG. 4 , gallery 670 shown in FIG. 6 , gallery 740 shown in FIG. 7 , the gallery shown in the layout section 880 of FIG. 8 , or gallery 940 shown in FIG. 9 . In some embodiments, step 1302 is omitted, and the user selects a graphic design as part of selecting the convert to graphic command, or the facility automatically selects a graphic design.
[0051] In step 1303 , the facility receives user input selecting a graphic design from the menu displayed in step 1302 . In step 1304 , the facility identifies text to convert into a textual hierarchy, and ultimately into a graphic, based upon the text selected by the user input received in step 1301 . In various embodiments, the facility uses a variety of techniques to identify text in step 1304 . In some embodiments, the facility identifies exactly the text that was selected by the user. Where the user selects text by designating a single location in the text, such as a text insertion point or a scroll position, the facility typically selects a body of text around that position, such as all of the text in a line, paragraph or other grouping of lines, page, or other text container containing the designated location in the text.
[0052] In step 1305 , the facility transforms the text identified in step 1302 into the form of a textual hierarchy.
[0053] In step 1306 , the facility transforms the textual hierarchy constructed in step 1305 into a graphic in accordance with the selected graphic design. In particular, the facility maps from each element at each level of the textual hierarchy to a corresponding element at a corresponding level in a template provided for the selected graphic design. In some embodiments, the facility performs step 1306 by converting the textual hierarchy constructed in step 1305 to a clipboard format, such as the HTML clipboard format, recognizable by a graphical layout engine. Next, the facility removes the identified text from the presentation—and, in cases where all of the text in one or more containers was selected, removes those containers—and adds a new graphic to the presentation at the same position and size as the removed text and/or text containers. The facility passes the HTML clipboard format hierarchy to the graphical layout engine, which creates elements of the graphic based upon the structure of the HTML clipboard format hierarchy, and populates those elements with the text contained in the HTML clipboard format hierarchy. In some embodiments, the facility performs aspects of step 1306 in accordance with U.S. patent application Ser. No. 10/955,271 filed on Sep. 30, 2004; U.S. patent application Ser. No. 10/957,103, filed on Sep. 30, 2004; and/or U.S. patent application Ser. No. 11/281,076, filed on Nov. 17, 2005, each of which is hereby incorporated in its entirety.
[0054] In step 1307 , the facility replaces the identified text in the document with the graphic generated in step 1306 . In step 1308 , the facility displays the textual hierarchy generated in step 1305 separately from the document such as in a floating window like floating window 560 shown in FIG. 5 . In step 1309 , the facility receives user input revising the textual hierarchy displayed in step 1308 . In step 1310 , the facility displays in the document a version of the graphic generated in step 1306 that has been revised in accordance with the revisions to the textual hierarchy received in step 1309 if appropriate. After step 1310 , the facility continues in step 1309 to receive additional user input revising the textual hierarchy. Though not shown in FIG. 13 , as discussed above, the user may also alter the generated graphic in a variety of other ways that do not involve revising the textual hierarchy on which it is based.
[0055] Those skilled in the art will appreciate that the steps shown in FIG. 13 may be altered in a variety of ways. For example, the order of the steps may be rearranged; substeps may be performed in parallel; shown steps may be omitted, or other steps may be included; etc.
[0056] It will be appreciated by those skilled in the art that the above-described facility may be straightforwardly adapted or extended in various ways. For example, the facility may generate graphics of a wide variety of types, based upon text in a variety of forms, having a variety of different types of formatting. Additionally, the facility may be used in conjunction with a variety of different application types; that is, applications for preparing a variety of different types of documents. Further, the facility may be used by programmatic users rather than human users; for example, the facility may be embodied in a subroutine or a web service called by another program that provides any needed input. While the foregoing description makes reference to particular embodiments, the scope of the invention is defined solely by the claims that follow and the elements recited therein. | A facility for generating a graphic image is described. The facility receives from a user a body of text whose creation is not subject to any rules or prototypes. The facility discerns from the body of text a textual organization. The facility then generates a graphic image conveying the discerned textual organization. | 6 |
FIELD OF THE INVENTION
[0001] This invention relates to a safety relief valve in a pressure relief system for a pressure vessel or for gas or liquid product pipelines, and more particularly to an improved spring-operated safety relief valve balanced against the effects of backpressure, wherein any pressure that may exist in the outlet piping when the valve is closed will exert a force on the closure member (spindle and seat) in an upward direction that is equal to and, therefore, in balance with, a downward force exerted on the closure member by outlet pressure to which the relief valve is exposed; this downward force normally having the effect of altering the valve set (opening) pressure were it not for the presence of an equal upward force. The seal that helps effect the balancing of upward and downward forces is of an improved configuration and preferably made of Teflon, which resists a wider range of chemical substances and temperature extremes than seals used in similar valve geometry in the prior art.
BACKGROUND OF THE INVENTION
[0002] Heretofore, balanced safety valves or balanced relief valves have been provided in pressure relief systems. While relief valves of various types have proven effective in applications where the fluid product is a benign gas or liquid at ambient or near-ambient temperatures and low to moderate pressures, they are not suitable for use in processes that are chemically incompatible with elastomer-type O-ring seals, or that have extremely low service temperatures or high backpressures. Most O-rings are not suitable for effective sealing when exposed to temperatures below approximately −60° F., and those known for their greatest chemically resistance, such as those of the perfluoroelastomer family, are not suitable below 0 to −20° F. The bellows in a balanced bellows-style valve may not be sufficiently durable in high backpressure applications.
[0003] Pressure relief discharge pipelines are frequently vented directly to atmosphere, where a conventional unbalanced spring-operated safety valve may be used due to the lack of backpressure present in the discharge lines that could vary the set pressure of the valve. Where the pressure relief system is handling hazardous or expensive fluids, discharge directly to atmosphere is not practical and may be contrary to environmental regulations. In these cases, one or more pressure relief valves would be installed such that each of the respective discharge pipelines is connected to a common header or manifold that leads to a central collection system or is routed back to an earlier stage of the fluid processing stream. The discharge header or manifold commonly contains a constant or variable level of pressure that may be due to design conditions of the fluid collection system or an actual discharge from one or more of the connected pressure relief valves. Such mainfold pressure, referred to in the industry as “superimposed backpressure,” would exist all the way back to the discharge side of each of the connected pressure relief valves and exert a net force on the valve closure member (disc or spindle) that is proportional to the value of the pressure in combination with the net surface area of the valve closure member. That is, when superimposed backpressure is allowed to act on opposing closure member surfaces that are not of equal area, as in an unbalanced relief valve, the set pressure of the relief valve is caused to change. Variable set pressures at a pressure relief valve installation are generally undesirable as they may compromise the safety of the equipment (tank, pipe, pump, etc.) being protected and will otherwise cause inconsistent system operation.
[0004] In balanced pressure relief valves that rely on a metal bellows to achieve pressure balance of the main closure member, some designs place significant restrictions on the amount of allowable backpressure to which the bellows can be exposed, as the bellows tends to be of thin, light construction and may be easily subject to rupture.
[0005] What is needed, then, is a balanced safety relief valve in a pressure relief system for a pressure vessel or for gas or liquid product pipelines, more particularly an improved spring-operated safety relief valve balanced against the effects of backpressure, where the internal sealing configuration can withstand high system pressures and is chemically compatible with a wide variety of process fluids and low temperature conditions.
SUMMARY OF THE INVENTION
[0006] This application discloses a safety relief valve balanced against the effects of backpressure, with an internal sealing arrangement that has greater compatibility with noxious or corrosive chemical processes and low service temperatures than prior balanced relief valve designs.
[0007] It is an object of this invention to provide a balanced safety relief valve assembly for rapid relief of excess pressure in gas and liquid systems, whereby valve set pressure is maintained at a constant value when exposed to backpressure through use of a main closure member (spindle) that has equal sized opposing surface areas exposed to backpressure so that backpressure does not bias the spindle in any particular direction, and effects on valve set pressure are negated.
[0008] Another object of this invention is to provide a balanced safety relief valve assembly with an internal spindle seal made substantially of polytetrafluoroethylene (PTFE), which is chemically inert and compatible with a wide array of industrial gases and liquids and process temperatures. PTFE can perform an effective sealing function at temperatures down to approximately −423° F.
[0009] It is a further object of this invention to provide a balanced safety relief valve wherein the spindle seal dampens spindle movements when the valve is open, through a seal configuration that results in pressure-induced frictional forces between the outboard edge of the seal and the mating machined guide surface in the valve body.
[0010] It is a further object of this invention to provide a balanced safety relief valve compatible for operation on both gas and liquid systems, where the operation in gas service results in a rapid opening (popping action)—characteristic of the term ‘safety valve’ as used in the pressure relief industry—and where the operation in liquid service results in initial slight opening and modulation followed by popping open—characteristic of the term ‘relief valve.’
[0011] It is a further object of this invention to provide a balanced safety relief valve that meets the material, design, and capacity certification requirements of Section VIII of the ASME Boiler and Pressure Vessel Code.
[0012] Other objects, features, and advantages of the invention will be apparent from the following drawings and specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a side sectional view of the safety relief valve assembly of the present invention;
[0014] FIG. 2 is a side elevation view of the safety relief valve shown in FIG. 1 but additionally showing the valve assembly fitted with inlet and outlet conduits;
[0015] FIG. 3 is an enlarged sectional view of the safety relief valve nozzle, spindle, and seat region shown in FIG. 1 , with an illustration of backpressure forces that may exist on the spindle with the valve in its closed position.
[0016] FIG. 4 is a general top view of the spindle seal shown in FIGS. 1 and 3 .
[0017] FIG. 5 is a sectional view of the spindle seal shown in FIG. 4 .
[0018] FIGS. 6 and 7 are side sectional views of the safety relief valve in the closed and open positions, respectively, for illustrating general flow patterns within the safety relief valve during normal operation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] Referring now to the drawings for a better understanding of this invention, and more particularly to the embodiment shown in FIGS. 1 and 2 , a balanced safety relief valve assembly is illustrated in a pressure relief system. The safety relief valve assembly has a valve body 1 fitted with an inlet bushing 6 formed with a threaded inlet 30 connected to system inlet pipeline 17 usually by an American National Standard Taper Pipe Thread (NPT) joint, or by an equivalent arrangement of pipe flanges with suitable bolting and gaskets. NPT connections screw together tightly with the use of wrenches, and are made leak-tight through the use of an appropriate sealing compound applied to the threads. Valve body 1 is also formed with threaded outlet 33 connected to an outlet pipeline 19 in an arrangement similar to threaded inlet 30 . The entire valve assembly, except for seats and seals, is made of metal parts, normally an appropriate grade of stainless steel, although other metals can be used for special applications.
[0020] With the valve closed, seat seal 5 carried by spindle or valve member 4 makes a leak-tight seal against an angled machined nozzle surface 6 a extending peripherily of the open top end of bushing 6 . The seat seal 5 is a plastic material such as PTFE or harder plastics of suitable composition. The seat seal 5 is held in place in spindle 4 by an annular retainer 9 , which in turn is retained in place with a screw 22 . To help prevent loosening of this threaded joint, a locking thread insert 27 fits between the male threads of screw 22 and the female threads inside spindle 4 . A spindle cap 12 is threaded into a thread upper opening 28 formed in the spindle. The spindle cap cooperates with spindle 4 to maintain spindle seal 29 in place.
[0021] Spindle 4 and spindle cap 12 are guided for vertical travel by concentric machined surfaces 1 b of body 1 , 4 e of spindle 4 and 12 a of spindle cap 12 . A radial clearance is provided between these machined surfaces preferably of on the order of approximately 0.001 to 0.003 inch. This clearance is large enough for fluid present in the outlet chamber 33 to migrate along the outside diameter of spindle 4 to chamber 32 . Use of corrosion-resistant stainless steel for these parts prevents buildup of corrosion products that would otherwise reduce these clearances over time.
[0022] It will be understood that the size of upwardly facing surface area 4 b exposed to outlet pressure within chamber 32 is necessarily made equal to downwardly facing surface area 4 c exposed to outlet pressure within flow outlet 33 .
[0023] Also referring to FIGS. 4 and 5 , the spindle seal 29 is made up of a solid TEFLON® element consisting of a heel 34 , outer sealing edge 35 , and inner sealing edge 36 . A spring 37 , made of stainless steel or other metal suitable for the fluid process, fits inside the TEFLON® element and provides rigidity and outward force to place the sealing edges 35 and 36 against body surface 1 b and spindle surface 4 f. With the spindle seal assembly in place in the safety relief valve and exposed to a pressurized fluid, spring 3 serves to provide a downwardly acting force tending to block fluid present in inlet 30 , and provide an additional force to cooperate with pressure within chamber 32 to expand sealing edges 35 and 36 into frictional sealing engagement with surfaces 1 b and 4 f against sealing edges 35 and 36 . The style of spindle seal 29 used in this product has a maximum pressure rating of 10,000 psig.
[0024] The safety relief valve spring 3 exerts the downward force on spindle 4 to oppose the upward forces due to pressure at inlet 30 . The amount of force exerted by the spring and, therefore, the valve set (opening) pressure is adjusted by turning pressure adjustment screw 10 with a wrench. Spring washers 2 provide an interface to transfer bearing forces between the spring 3 and pressure adjustment screw 10 at the top end of the spring, and between the spring and spindle cap 12 at the bottom end of the spring. The pressure adjustment screw is supported by female threads tapped into the top of bonnet 8 . With the valve normally closed and in service, lock nut 11 and cap 18 are secured in place on the pressure adjustment screw along with lock wire 23 and lead seal 24 to prevent unauthorized or inadvertent adjustments to set pressure.
[0025] Holding the spring and spring washer subassembly stationary and in alignment with the lower internals is bonnet 8 , held down with retaining ring 21 and bonnet base 14 , the latter being clamped directly against the top of body 1 with bolts 13 , lockwashers 26 , and nuts 20 . Not shown are clearance holes in items 1 and 14 used for positioning the bolts. In a version of this safety relief valve (not shown) intended for higher pressure service, bonnet 8 is a larger cast component that includes an integral lower bolting surface, so bonnet base 14 and retaining ring 21 are not used. The space 31 within the bonnet 8 is not exposed to system pressure due to the presence of spindle seal 29 , which prevents escape of fluid upwardly from chamber 32 .
[0026] The remaining sealing areas of the valve assembly are bushing seal 7 and rear seal 16 , both usually made of TEFLON®. A bolt 15 plugs the rear of body 1 and holds seal 16 in place. A nameplate 25 is attached to the outside of body 1 to identify valve set pressure and identifying data.
Operation
[0027] A set or opening, pressure is specified by the user of the safety relief valve according to the operational parameters of their pipeline system, vessel, or tank. The value chosen corresponds to the point at which excess system pressure must be relieved, and is frequently the maximum allowable working pressure as defined by the governing piping or vessel design code.
[0028] Referring to FIGS. 1, 2 , 6 , and 7 , when the system connected to the valve via inlet pipe 17 is operating at normal pressure, the safety relief valve remains closed below set pressure, due to the downward force established by spring 3 , being greater than the upward force generated by pressure at inlet 30 acting over the total circular area enclosed by the sealing edge of valve seat 5 . When inlet pressure rises to the point where the upward pressure force overcomes the downward spring force, valve seat 5 breaks contact with valve seat surface 6 a and fluid flows through the valve from inlet 30 to outlet 33 .
[0029] When the service fluid is a gas or vapor, the valve opening is rapid and characterized by a popping action, with spindle 4 immediately rising to the top of its travel such that the spindle upper surface 4 b abuts against downwardly facing body surface 1 c, as shown in FIG. 7 . A rounded annular recessed area 4 d, or huddling chamber, formed in the downwardly facing surface of spindle 4 , most visible in FIG. 3 , acts to let fluid quickly collect under the spindle after first flowing past valve seat surface 6 a, leading to a further rapid pressure buildup distributed over an area much larger than the seat, resulting in the subsequent pop action. When the service fluid is a liquid and system pressure increase is slow, the initial opening is gradual and the liquid flow stream may be a small trickle. As inlet pressure is allowed to increase further, the liquid flow will gradually increase until, at approximately 7-½% above set pressure, the valve will pop the rest of the way open in a fashion similar to that when operating with a gas.
[0030] As excess system pressure abates, the reduced pressure at inlet 30 allows the downward spring force to overcome the upward pressure force, and the spindle 4 completes its downward travel into engagement with valve seat surface 6 a. During valve closure, outlet pressure still exerting an upward force on spindle seal 29 not only continues to help effect a good seal at sealing edges 35 and 36 ( FIG. 5 ), but also induces some drag between sealing edge 35 and the mating surface 1 b of body 1 to resist the tendency the spindle may have to chatter, or cycle rapidly up and down due to fast changes in pressure distribution.
[0031] Referring to FIG. 3 , the feature that enables this safety relief valve to be balanced against backpressure involves the provision of spindle with equal sized upwardly and downwardly facing areas 4 c and 4 b, which are exposed to back pressure present in outlet chamber 33 , due to the flow communication provided between chambers 32 and 33 .
[0032] The backpressure acting on the upper and lower surfaces of spindle 4 adds no net additional vertical force to the spindle, either up or down, and allows the spring setting alone to fix the valve set pressure and keep it stable. | A safety relief valve provides for the equalization of backpressure across a valve spindle by providing for flow of fluid between equal sized upper and lower surfaces of the spindle in order to render the valve set point independent of backpressure, such that opening characteristics are controlled solely by the setting of the valve control spring. A seal preferably formed of TEFLON® is provided to prevent the escape of fluid from the valve body, which would otherwise adversely affect the pressure balance between the upper and lower surfaces. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a process for the treatment of waste sheet floor covering material for the purpose of converting it into raw material to be used in the manufacture of fiber reinforced tile floor material.
2. Description of the Prior Art
U.S. Pat. No. 3,056,224 discloses a sheet vinyl floor covering material which has the asbestos filler backing material fastened to a vinyl wear layer material.
U.S. Pat. No. 2,773,851 discloses vinyl composition for making a vinyl tile made with filler material.
U.S. Pat. No. 2,814,075 discloses a technique for recovering scrapped foamed latex. A Banbury mixer is used to grind up the scrap latex for subsequent reuse.
U.S. Pat. No. 2,853,742 is directed to a process for recovering powdered rubber from scrap vulcanized rubber through the use of a Banbury mixer.
SUMMARY OF THE INVENTION
The invention is directed to the concept of recovering scrap sheet flooring material such as that shown in U.S. Pat. No. 3,056,224. A Banbury mixer is used to grind pre-diced scrap. The Banbury mixer abrades away and pulverizes the backing of the sheet material, which backing is an asbestos filler material. The ground and pressurized scrap is mixed until the mixer reaches 300° F. (149° C.). A high binder scrap or virgin resin and plasticizer is added to the mix. An additional stabilizer may be added and thereafter the material is mixed to approximately 350° F. (176° C.). The material is then discharged from the Banbury mixer and may be utilized as part of the raw material used to make the vinyl tile of U.S. Pat. No. 2,773,851.
BRIEF DESCRIPTION OF THE DRAWING
The drawing is a schematic sectional representation of a Banbury mixer.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Normally, the sheet flooring material of U.S. Pat. No. 3,056,224, if it was defective, would be scrapped and dumped in a land-fill dump. Defects of the nature being talked about are visual defects in the arrangements or lay-up of the chips which give an unpleasant aesthetic effect. Because of the chips are fastened to the backing, which is a beater saturated asbestos fiber felt, it was not considered feasible in the past to attempt to salvage scrap material. Several investigations were conducted into the possibility of removing the backing material from the vinyl face material, but invariably, these techniques involved high expenses or other production problems. Through the technique to be described below, it is now possible to take scrap sheet flooring material, such as disclosed in U.S. Pat. No. 3,056,224, and recover the scrap material for use in another product.
The recovered scrap material will be used to form a product such as that disclosed in U.S. Pat. No. 2,773,851. The product of that patent is a vinyl resin floor tile which contains filler material. The recovered scrap, processed by the invention to be described below, will be used as part of the raw material for forming the product of U.S. Pat. No. 2,773,851 and the asbestos fiber of the backing of the product shown in U.S. Pat. No. 3,056,224 will constitute part of the fibrous filler in the product of U.S. Pat. No. 2,773,851. Of primary importance herein is the fact that the recovered scrap replaces some of the virgin material which normally would be needed.
Scrap material of a structure according to U.S. Pat. No. 3,056,224 will initially be in sheet form in sheets of 6 foot (183 cm) width and of variable lengths. These sheets will be run through conventional dicing machines and converted to diced 1/4 inch (0.6 cm) by 1/4 inch (0.6 cm) square cubes; each cube will have basically the cross section shown in FIG. 3 of U.S. Pat. No. 3,056,224. That is, each cube will have on one side, the asbestos backing material, and on the other side thereof, some vinyl material which forms the wear layer of the flooring. These cubes will be charged into a conventional Banbury mixer.
The Banbury mixer has long been known and used in the rubber and plastic industry for masticating raw materials as well as mixing and compounding rubber and/or vinyl materials with fillers and other compounding agents. The machine basically comprises a pair of blade rotors 1 and 2 which are mounted for rotation adjacent each other in opposite directions within semi-cylindrical troughs or chambers 3 and 4. The rotors are so shaped as to smear the material in the chambers against the walls thereof, forcing the material upwardly and kneading it as it moves towards the longitudinal center of the machine from one chamber to the other chamber. The material is generally held within the chamber of the machine by a pneumatically operated ram 6. This ram is also capable of applying pressure to the mix within the Banbury mixer so that the mixing will be carried out under pressure. The general construction of the Banbury machine, in the form in which it has been used extensively in industry for breaking down and masticating materials and for compounding the same with fillers, etc., is shown, for example, in the Banbury U.S. Pat. No. 1,881,994.
After the pre-diced chips for sheet flooring are charged into the Banbury mixer (at port 5), pressure is applied by ram 6. The material is masticated for about 6 minutes with the ram resting on the mix (a ram pressure of 35 pounds (15.8 kg) per square inch (2.54 cm) is maintained on the air cylinder operating the ram) until the batch mix reaches a temperature of 300° F. (149° C.). At this point, the ram is lifted and then virgin resin, additional plasticizer and stabilizer are added. The batch is then mixed for about 3 minutes or until it reaches 350° F. (176° C.) to blend the new materials in with the materials previously in the Banbury mixer. This material is then discharged from the Banbury mixer and may be used in conventional manufacturing processes to form the product of U.S. Pat. No. 2,773,851.
It is possible to substitute low filler scrap from other unbacked high binder scrap sources in lieu of the virgin resin added to the Banbury mixer. It is also possible to combine various types of scrap in the original pre-diced mix. Determination of what will go into the Banbury mixer is simply a matter of balancing materials that are available against the result desired. As shown in U.S. Pat. No. 2,773,851, the mix for forming the tile product should contain a certain range of material. Therefore, one would initially charge into the Banbury scrap material which contains the different materials to be used in the end product. After the scrap is broken down by the intense shearing action of the mixer, then supplemental materials such as stabilizer, plasticizer, virgin resin, high vinyl scrap, or other materials are added to bring the Banbury mix up to a proportion of ingredients which will yield a product that can be used to replace a portion of the virgin raw materials in a tile batch falling under the standards for ingredients set forth in U.S. Pat. No. 2,773,851.
As one specific example of a product which has been carried through the above process, the following example is given. The Banbury mixer is initially charged with 600 pounds (270 kg) of pre-diced cubes of the material such as that shown in U.S. Pat. No. 3,056,224. This material is mixed for about 6 minutes with the ram resting on the mix and the batch is mixed until it reaches 300° F. (149° C.). Then 86 pounds (38.7 kg) of virgin resin are added along with 27 pounds (12.2 kg) of plasticizer and 6 pounds (2.7 kg) of stabilizer. This is then mixed with the ram applied for about 3 minutes until a temperature of 350° F. (176° C.) is reached. This then yields a product having the following composition.
______________________________________Ingredients % By Weight______________________________________Resin 32.3Plasticizer & stabilizer 10.8Asbestos fiber 25.3Limestone 31.6______________________________________
The above composition of material can then be utilized in the process of U.S. Pat. No. 2,773,851 to form a portion of the formulation of the product of that patent. The above composition of material will be used to form 2% to 12% of the final mix of material used to form the product of U.S. Pat. No. 2,773,851. For every 50 pounds (22.5 kg) of the above described recovered scrap mix from the Banbury used to make the product of U.S. Pat. No. 2,773,851, there is the following saving of material:
______________________________________Resin 10.0 lbs. (4.5 kg)Plasticizer 3.5 lbs. (1.6 kg)Asbestos 12.5 lbs. (5.7 kg)Limestone 16.0 lbs. (7.3 kg)______________________________________
The difference between the total of the above and 50 pounds (22.5 kg) is the virgin resin and plasticizer which was added after the first blending step of the pre-diced chips. It is apparent that the use of tons of scrap per week recovered as described herein will result in substantial cost savings in the manufacture of floor tiles. | Scrap sheet floor covering is recovered for reuse through the use of a Banbury mixer. The mixer grinds pre-diced scrap and abrades away asbestos filler backing material from the vinyl wear layer material. Binder scrap or virgin resin and plasticizer is added to convert the scrap sheet floor material to a raw material for use in manufacturing fiber filled vinyl tile. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention is a continuation of co-pending patent application Ser. No. 09/974,337, filed Oct. 10, 2001 “Networked Personal Security System.” The subject invention is generally related to personal security alarms or panic button devices and is specifically directed to a personal alarm system having network communication capability whereby the user can generate a signal to a remote location from any monitored area.
[0003] 2. Description of the Prior Art
[0004] There are numerous devices that allow an individual to send a panic signal to a remote location in order to seek assistance when certain events occur. For example, many semi-invalid medical patients will wear a panic button as pendant around their neck, with the panic button adapted to be manually pushed in order to signal a medical emergency. The button device then transmits a signal to a remote monitoring station for initiating a response. Basically, the device transmits a radio signal to a receiver and identifies the patient. The response is typically a telephone call to the patient's residence and if no answer is received, emergency personnel are dispatched. This system works relatively well if the patient stays near the identified telephone or remembers to inform the monitoring system personnel of his/her whereabouts if he/she leaves an identified area. A major drawback to this system is the inability to track the location of a patient. Another drawback is the requirement that the panic button be manually activated in all circumstances. In certain situations, it may be impossible for the wearer to manually activate the system, rendering the panic system ineffective.
[0005] There are many applications both in the medical field and in other fields where a personal panic alarm system would be useful, particularly if the alarm identified the location of the personnel and even more so if under certain conditions the system were automatically activated. For example, such a device would be useful in school systems wherein the teaching staff could wear the panic button device and immediately signal security and/or administrative personnel of an incident. This would be particularly useful if the system identified the location of the teacher as well as in many instances identified the type of emergency. To date, no known devices provide such features and capability.
[0006] There are a number of devices available that address location tracking. As an example, U.S. Pat. No. 5,276,496 discloses an optical system for locating a target within a defined area by comparing the received light intensity between the several sensors. U.S. Pat. No. 5,355,222 discloses an optical position sensor, wherein an object with a luminous transmitter is viewed by an array of binary-patterned sensors. U.S. Pat. No. 5,548,637 discloses a telephone-forwarding system wherein people are ‘tagged’ with optical transmitters, and stationary receivers located throughout the premises determine the person's location and nearest telephone extension.
[0007] U.S. Pat. No. 4,275,385 discloses a personnel locator system wherein people carry coded infrared transmitters throughout a facility. Zoned receivers detect the coded signals and determine the person's location. U.S. Pat. No. 5,062,151 discloses a personnel location system, wherein people carry coded infrared transmitters, which activate infrared receivers in each equipped room.
[0008] While each of the prior art devices address certain location issues, none of the known devices provides an affordable, comprehensive personal signaling and locating device.
SUMMARY OF THE INVENTION
[0009] The subject invention is directed to a personal alarm system that is affordable, portable and fully compatible with a comprehensive security system such as that shown and described in my co-pending U.S. patent application Ser. No. 09/594,041, entitled: Multimedia Surveillance and Monitoring System Including Network Configuration, filed on Jun. 14, 2000. The device can be worn or carried by the user, may be activated at any time by the user and/or may be automatically activated to send a signal to any remote monitoring station on the network. The device also identifies the user as well as the user's location within the monitored area. In the preferred embodiment, the alarm-sending unit is designed to fit within a box the size of a small cell phone or pager. The unit includes an ID memory for identifying the user, and has on-board circuitry for generating a signal to a wireless transmitter for sending the signal to a to a local receiver for inputting the signal onto the network.
[0010] In one embodiment of the invention, the device can be worn on the person of key personnel for activating a signal that is transmitted to a remote location such as security personnel or a guard station processor or the like. As an example, the device of the present invention is particularly useful in aircraft applications where a crew member can send a distress signal directly to ground control in the event of an emergency or catastrophic event. In its simplest form, the device may be a wired “ON-OFF” button placed at a strategic location in the aircraft, such as, by way of example, on the control panel of the cockpit and/or in the galley or other strategic location in the passenger cabin. In an enhanced embodiment, the device is wireless and may be carried directly on the person of a crew member. Preferably, each crew member would be armed with the wireless device.
[0011] In its simplest form, the device simply sends an emergency signal to ground control, thus alerting ground control that an emergency has occurred and that the aircraft requires immediate monitoring and communication. In an enhanced embodiment, the device is linked to a comprehensive on-board security system and in addition to transmitting a signal to ground control, also activates the security system to collect additional data and store the data in the on-board recorders as well as optionally sending the data to the ground control in a live, real-time transmission.
[0012] One of the advantages of this system is that where loop recorders are used, such as, by way of example, thirty minute loop recorders common on many commercial aircraft, an activation signal can download the stored information and begin live transmission of new information. This permits the thirty minutes of data recorded prior to the incident to be received at ground control and minimizes the current dependency of finding the “black box” recorder. This also permits important data relating to the events prior to the incident as well as data after the incident to be collected for investigation and reconstruction of the event.
[0013] The wireless system has numerous advantages in preserving the ability to transmit emergency signals. For example, it is virtually impossible to simultaneously disarm all wireless components, preserving some transmission capability even if certain of the devices are disabled. Also, when used in combination with the comprehensive wireless system, it is possible to initiate and transmit information even after the integrity of the aircraft has begun to disintegrate.
[0014] In additional embodiments of the invention, the device may be more sophisticated to permit the type of emergency to be embedded in the emergency signal. For example, it is useful to distinguish between a fire emergency, a medical emergency and a security emergency since the response to each will be different.
[0015] The device of the subject invention is also well suited for use in facility security applications where roving personnel may have need for a personal alarm device in order to signal response personnel as to the presence of an emergency condition. For example, the device is very useful for teachers in managing classroom or campus emergencies. In this application, the device is location specific, not only sending a signal to the monitoring station, but also identifying the sender and the sender's location.
[0016] In one embodiment, a centralized, networked RF receiver is used with the personal alarm units. One or more of these RF receivers may be installed in order to provided adequate coverage of the monitored area. The signals generated by the personal alarm are received by the RF receiver(s) and decoded, whereupon the system processor assembles a message, packetizes it as necessary, and sends it to one or more monitoring stations via the intervening network and network interface The signals may be digitized where desired.
[0017] In an enhanced embodiment, beacon transmitters are installed at various locations around the monitored facility, again connected to a common facility network. The beacon transmitters are designed to transmit a unique beacon ID signal at regular intervals. The beacon signals may also be generated by a control signal from a system processor on the facility network. These signals may be infrared, RF, ultrasonic or other known format. The personal alarm unit will store the beacon signal each time it is received. When a signal is initiated from the personal alarm unit it will identify the location of the sender by transmitting the last stored beacon signal, providing an efficient, inexpensive and accurate method of tracking the user.
[0018] In large enclosed areas such as a gymnasium or auditorium multiple beacons may be employed for further refining the location of a sending unit. It is also an important feature of the invention that GPS technology may be employed in outdoor settings such as a stadium, campus grounds or the like. This is useful independently of the beacon technology, or may be employed in connection with the beacon technology in order to track location of a user both internally and externally while in the monitored area.
[0019] It is, therefore, an object and feature of the subject invention to provide a personal alarm device capable of transmitting a signal to a remote location upon activation.
[0020] It is also an object and feature of the subject invention to provide a personal alarm device capable of activating a security and surveillance system when the device is activated.
[0021] It is an additional object and feature of the subject invention to provide a personal alarm device for initiating the transmission of event data to a remote location when the device is activated.
[0022] It is also an object and feature of the subject invention to provide a personal alarm device capable of sending an alarm signal to a remote station while identifying the identity and/or the location of the user.
[0023] It is another object and feature of the subject invention to provide an efficient method of monitoring and identifying the location of each unit in the system.
[0024] It is an additional object and feature of the subject invention to provide the means and method for supporting a personal wireless alarm system via a local area network (LAN) or wide area network (WAN).
[0025] It is yet another object and feature of the invention to provide a personal alarm system that may be polled by the monitoring stations on demand.
[0026] It is another object and feature of the subject invention to provide a personal alarm that may automatically send a signal upon the occurrence of certain, specified events.
[0027] It is a further object and feature of the subject invention to provide a personal alarm capable of providing voice communication with the monitoring station.
[0028] It is a further object and feature of the subject invention to provide a personal alarm system capable of identifying the type of emergency causing the need to initiate a signal.
[0029] It is a further object and feature of the subject invention to provide an intercom feature, signaling designated stations and transmitting microphone signals to that station.
[0030] It is a further object and feature of the subject invention to signal the location of an intercom call to the called station, such as presenting a room name and/or a signaling icon on a map at the called station.
[0031] It is a further object and feature of the subject invention to provide an “open microphone” after the initiation of an emergency or intercom signal.
[0032] It is a further object and feature of the subject invention to incorporate the panic button receiver in multipurpose network appliances, such as wall clock appliances, video camera appliances, smoke detector appliances, and the like.
[0033] It is a further object and feature of the subject invention to incorporate the beacon transmitter (or receiver depending on the exact method of implementation) in multipurpose appliances, such as wall clock appliances, video camera appliances, smoke detector appliances, and the like.
[0034] Other objects and features of the invention will be readily apparent from the accompanying drawings and detailed description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIG. 1 is a perspective view of a basic personal alarm device in accordance with the teachings of the subject invention, including a basic block diagram of the circuitry for the device.
[0036] FIGS. 2A and 2B illustrate a decision flow diagram for one embodiment of the device.
[0037] FIG. 3 is a diagram of a network system for supporting the device of the subject invention.
[0038] FIG. 4 illustrates a beacon transmitter, which operates without a supporting facility network.
[0039] FIG. 5 is a perspective view of an enhanced personal alarm device with additional features, including a basic block diagram of the circuitry for the device.
[0040] FIGS. 6A and 6B illustrate the decision flow diagram for the device as modified in FIG. 5 .
[0041] FIG. 7 illustrates a comprehensive system incorporating the teachings of the subject invention.
[0042] FIG. 8 is the timing decision flow diagram for the configuration of FIG. 7 .
[0043] FIGS. 9A and 9B illustrate a beacon signal management system for supporting beacon signal management of a system in accordance with the subject invention.
[0044] FIG. 10 illustrates a system for housing the beacon transmitter/receiver in a wall appliance.
[0045] FIG. 11 shows a scheme for providing complete coverage of a target area utilizing strategically placed beacon transmitters/receivers.
[0046] FIG. 12 depicts an adaptation of the system to support usage in a large outdoor area such as a stadium.
[0047] FIG. 13 depicts a modification of the system of FIG. 1 incorporating an ultrasonic transducer for transmitting encoded information.
[0048] FIG. 14 illustrates a system for receiving, processing and disseminating the message received from a handheld device by a local networked appliance.
[0049] FIG. 15 illustrates a typical application of the system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0050] FIGS. 1-3 depict a basic embodiment of the system that does not included encoded location information. This application is particularly well suited for confined environments such as aircraft and the like, where the location of the person sending the signal is not as critical as in large installations such as a high school campus. In its simplest form, the alarm unit 5 of FIG. 1 comprises a simple panic button, which is a radiator that transmits a coded signal to the closest receiver via the antenna 40 , with the receivers of FIG. 3 being conveniently located and connected to the network. Receivers can be integrated into other devices, such as wall clock appliances, thermostats, smoke detectors, motion detectors, and the like in the room or facility where the alarm unit is to be used. The transmitter radiator may comprise any of a number of signal generating protocols, such as, by way of example: RF (a potential location problem for certain applications in that it goes through walls so exact room location and identification is more difficult); LIGHT, such as IR, (directional and can be blocked by clothing and other obstructions); and ULTRASONIC (includes the dual advantages of being contained to a room, while not being as directional as IR and not so blocked by clothes. The specific method used will be dictated by the application and by cost/benefit factors and is well within the scope of knowledge of those skilled in the art.
[0051] The device of the subject invention may send the signal directly to a transmitter for sending the signal to a remote station, as shown in FIG. 1 , or may be adapted for sending a signal to the installation security system for activating it as well, as shown in FIG. 10 . A detailed description of aircraft security systems are shown and described in my issued U.S. Pat. Nos. 5,798,458, 6,009,356, 6,253,064B1, and 6,246,320B1, incorporated by reference herein. A detailed description of a comprehensive multimedia security system is shown and described in my copending application Ser. No. 09/594,041, filed on Jun. 14, 2000, entitled: “Multimedia Surveillance and Monitoring System Including Network Configuration, also incorporated by reference herein.
[0052] In most cases, the receiver of FIG. 3 will be incorporated in other appliances in the facility. For example, a room monitor in a school may be mounted on a wall and may include various sensors as well as the receiver. A detailed description of such devices is incorporated in my co-pending application entitled: Multimedia Network Appliance for Security and Surveillance Applications, (Docket No. 081829.000026) Ser. No. ______, filed on Sep. 21, 2001, and incorporated herein by reference. Accordingly, FIG. 1 shows a wireless personal alarm 5 , housed in an enclosure similar to a pager. The alarm has one or more pushbutton switches S 1 -S 3 , to notify a monitoring station of an emergency condition. As depicted in FIG. 2A , upon activation via switches S 1 , S 2 , or S 3 , the internal processor 10 of FIG. 1 encodes and transmits a message containing the personal alarm unit ID number and the emergency ID number. Optionally, the alarm may be arranged to transmit audio from the environment near the pager as depicted in FIGS. 1 and 2 B. Microphone audio may be transmitted using conventional analog methods, or may optionally be digitized and compressed via A/D converter 31 and compressor 32 in FIG. 1 . For example, either of the following schemes may be utilizes: analog transmission of the microphone from the panic button with A/D and optional compression at the receiver/appliance end, or optional compression and digital transmission at the panic button end, with digital reception and digital relay at the receiver/appliance end.
[0053] It should be understood that the terms encoder and decoder as used throughout the application are intended to mean modules adapted for modifying a transmitted signal so that it is compatible with a receiver. In the simplest form, wherein the signal generator and the signal receiver are fully compatible, the encoder and decoder modules are unnecessary. In other instances, the protocol may have to be modified, or an analog signal may have to be converted to a digital signal and vice versa. In some instances, where it is clear that a signal is generated in an analog format (such as an analog microphone, see microphone 30 in FIG. 1 ) and is processed by a digital module (see the compressor 32 in FIG. 1 ) the “encoder” or “decoder” may be illustrated as a simple A/D converter.
[0054] The audio may be transmitted as analog or digital. If analog, it needs to be digitized and optionally compressed before introduction to the LAN or WAN network.
[0055] FIG. 3 depicts a centralized, networked RF receiver used with the personal alarm units. One or more of these RF receivers may be installed in a facility to provide adequate coverage of the premises. Personal alarm signals received by antenna 50 are demodulated by the wireless receiver 55 . These received messages are decoded via decoder 60 , and passed to system processor 70 . Processor 70 thereupon assembles a message, packetizes it if necessary, and sends it to one or more monitoring stations 85 via the intervening network interface 75 and network 80 . Optionally, audio transmitted by an active personal alarm unit and received by the wireless receiver 55 may be digitized by A/D converter 65 , then packetized by processor 70 , and conveyed to the monitoring station(s) via the network and associated interface. If the microphone audio had been transmitted digitally, then the system processor 70 need only packetize the audio data prior to transmission via network interface 75 .
[0056] As indicated in the drawing the network can be a wireless LAN (WLAN), a wired LAN, a modern/PSTN (public switched telephone network), two-way pager, CDPD, or other suitable network system. One embodiment of a suitable network system is shown and described in my previously mentioned co-pending application Ser. No. 09/257,720, entitled: Network Communication Techniques for Security Surveillance and Safety System.
[0057] FIGS. 4-6 illustrate a useful enhancement to the system, wherein numerous beacon transmitters are installed at various locations around the facility. Beacons transmit their unique ID to Personal Alarm Units, which thereby maintain a knowledge of the ID of the nearest beacon. When a Personal Alarm Unit needs to transmit an emergency indication, it can thereby notify one or more facility receivers of its ID, nearest beacon ID, and the type of emergency.
[0058] As shown in the circuit in FIG. 4 , the beacon transmitters are not required to be attached to any common network, and transmit a unique Beacon ID number at regular intervals. The beacons may employ infrared, RF, or ultrasonic energy to transmit their ID in to the local area. In the embodiment shown, each beacon transmitter includes a processor 100 with program memory 90 and a beacon ID memory 95 for introducing unique beacon identifying signals to the processor 100 . The processor output is encoded at encoder 105 and sent to the various transmitters such as the IR transmitter 110 , the RF transmitter 115 , or the ultrasonic transmitter 120 and the like. A typical sequence is shown in the flowchart of FIG. 4 , showing that once the timer is initialized the beacon identification signal will be blocked from transmission until the expiration of a pre-selected timer interval,
[0059] In FIG. 5 , an enhanced personal alarm is equipped with a beacon receiver, using infrared, RF, or ultrasonic methods as in the case of the beacon. The personal alarm unit receives and stores the ID number of the nearest beacon, as indicated at beacon receiver 135 . The personal alarm unit receives the identifying signal from the beacon via beacon receiver 135 . The beacon ID number is decoded by beacon decoder 145 and introduced into the unit processor at 150 . As in the embodiment of FIG. 1 the program memory 125 and device ID memory 130 provide device specific identify data to the processor. When one of the switches S 1 , S 2 , or S 3 is depressed, processor 150 formulates a message containing the personal alarm ID, the most recent beacon ID, and an indication of which switch was pressed. In this embodiment the encoder 155 encodes the processor output and introduces it to the transmitter 160 for wireless transmission via the antenna 165 . The microphone 140 permits direct audio input to the system from the unit. Audio may be transmitted in analog form, or may be digitized by A/D converter 141 and compressed by compressor 142 , thence transmitted digitally. The unit is shown at 170 and includes the activation switches S 1 , S 2 , S 3 , the microphone 140 and the antenna 165 .
[0060] Optionally, the personal alarm may store more than one beacon ID number for those cases where the personal alarm unit is moving through the facility, or may be in an area covered by more than one beacon.
[0061] It will be noted that the receiver is programmed to listen for or sense beacons and to store the last one detected. Then if a panic button is pressed when the panic button unit IS NOT in range of a beacon, the last know beacon ID will be used for transmission of location. This would perhaps not send the exact location, but would be close because it is the last substantiated location. As shown in FIGS. 6A and 6B , the personal alarm units may operate in either a continuous fashion, or in an as-needed fashion. In FIG. 6A , the personal alarm periodically sends it's unit ID number, last beacon ID number(s), and emergency ID number (if any). In FIG. 6B , the personal alarm transmits only when one of switches S 1 -S 3 are activated. The beacon generators do not necessarily need to be networked, which permits that common power be used. Networked beacon generators require network wiring, or wireless network infrastructure.
[0062] The utility of the system may be greatly enhanced by connecting all the facility's beacon units to a common network, as depicted in FIG. 7 . In this enhancement, the beacon transmitter of FIG. 4 is equipped with a wireless receiver, to receive transmissions from personal alarm units within it's immediate area. Additionally, the beacon transmitter/receiver is connected to a network or LAN serving the facility, allowing emergency transmissions from personal alarm units to be disseminated throughout the network. As before, the beacon transmits its unique beacon ID number into the local area, again using infrared, RF, or ultrasonic methods, as indicated by the antenna 180 and RF transmitter 185 , the IR transmitter 190 and generator 195 , ultrasonic transducer 205 and generator 200 , respectively. The beacon ID memory is provided by a discrete memory circuit 235 . Additionally, the beacon unit of FIG. 7 has a RF receiver 215 with antenna 210 , capable of receiving the transmissions from the personal alarm units of FIG. 1 or FIG. 5 , if any, located within its immediate area. The signal received and demodulated by the wireless receiver 215 is decoded at decoder 225 and introduced into the processor 230 . The processor formulates a message containing the personal alarm ID, alarm type, and beacon number transmitted by the personal alarm unit. This message is introduced to the network 245 via the network interface 240 for transmission to the monitoring station 250 . The antenna 255 provides the means for transmitting and receiving signals from the RF transmitter 265 and the RF receiver 270 via a transmitter/receiver switch 260 , permitting reduction of circuit redundancies. Since each beacon unit has it's own wireless receiver for receiving emergency transmissions from the personal alarm units, the beacon units may supplement or replace the facility-wide RF receivers depicted in FIG. 3 .
[0063] In an alternative embodiment, the dual antennas 180 and 210 in FIG. 7 may be replaced by a single shared antenna. In this embodiment, a transmit/receive switch 260 connects antenna 255 to either transmitter 265 or receiver 270 . As before, the output signal from encoder 220 is passed to the RF transmitter 255 , whilst the output from RF receiver 270 is passed to decoder 225 for decoding.
[0064] As shown in the flowchart of FIG. 8 , the beacons transmit their beacon ID at regular intervals, based on an internal timer. The beacon may additionally transmit its beacon ID upon request from the monitoring station(s). The personal alarm units from FIG. 5 may interact with the networked beacon of FIG. 7 according to the flowcharts of FIG. 9A and FIG. 9B . In FIG. 9A , the personal alarm unit receives the beacon signal, decodes the beacon ID number, waits for a unique time interval to pass, then encodes and sends it's unit ID, received beacon ID, and emergency ID (if any). The unique time interval is derived from the personal alarm unit's ID number, such that no two personal alarm units will have the same interval. That prevents the case where multiple personal alarm units respond to the beacon at the same instant, and thereby mutually interfere.
[0065] In FIG. 9B , the personal alarm unit responds to a beacon's transmission, as before. Additionally, the personal alarm contains a timer that determines when an excessive time has elapsed with no beacon signal received. Upon this detection of beacon loss, the personal alarm transmits it's unit ID number, last-heard beacon ID number, and emergency ID (if any) at periodic intervals. A facility-wide receiver as in FIG. 3 may receive such transmissions.
[0066] FIG. 10 depicts a beacon transmitter/receiver housed in a wall clock. Suitable network time protocols may be employed to accurately time-stamp received alarms, as well as to set the clock. The time stamped location data thus derived may be useful in reconstructing a person's movements around the facility. As shown, the beacon signal may be transmitted using RF techniques (transmitter 280 and antenna 275 ), IR techniques (transmitter 290 and diode 285 ) or ultrasonic techniques (transducer 310 and generator 305 ). As previously described, the panic button may transmit an ID signal to the system via the antenna 315 and the wireless receiver 320 (such as the networked appliance as shown and described in my aforementioned U.S. patent application Ser. No. ______). The encoder 295 and decoder 300 are connected to the processor 325 , as previously described, for providing a signal link to the network 340 and monitor 345 via the network interface 335 . The clock configuration is shown at 346 with a digital clock display such as LED, LCD or electrolumenescent 347 and the signal antenna 275 .
[0067] In another embodiment for implementing the geo-location system where there is no beacon, but there are networked receiver appliances available the panic button will send a continuous signal, allowing continuous location determination via the networked appliance for automatic call dispatch and other responses as described. In the alternative, the panic button signal will be generated only when a button is pushed, with the receiving networked appliance providing the location information.
[0068] As illustrated in FIG. 11 , large enclosed areas such as auditoriums or gymnasiums (the outer boundaries or walls of which are shown as line 350 ) multiple beacons may be employed. As depicted in FIG. 11 , the beacons B 1 , B 2 , B 3 , B 4 are deployed so as to have overlapping areas of coverage, such that a personal alarm unit is always within range of at least one beacon. Activated, the personal alarm unit can transmit the beacon ID number of all beacons it currently receives, or make a decision about the ID that is transmitted based on signal strength, frequency of beacon receptions, or other criteria.
[0069] FIG. 12 depicts an adaptation of the system to support usage in a large outdoor area such as a stadium. Such an area may be beyond the range of the beacon transmitters, such that the personal alarm unit 400 does not have any beacon location information available to send upon demand. In this instance, the personal alarm unit is supplemented with a GPS receiver 355 . When the alarm is activated by activation of switches S 1 , S 2 or S 3 , or periodically activated by the processor 375 at predetermined intervals, the personal alarm unit sends its unit ID number and other identifying information from memories 365 and 360 , GPS coordinates from receiver 355 , and emergency code as indicated by the selection of switch S 1 , S 2 or S 3 (if any). For improved accuracy, the GPS data may be supplemented with DGPS correction data. The processed signals communicate with the system receiver via encoder 380 , transmitter 390 and antenna 395 .
[0070] An office button 54 may also be included. In the illustrated embodiment this is an intercom activation button permitting audio transmission between the unit and the office either directly through the unit or by remotely activating the networked intercom appliance in the operating range of the unit. This can be used in both emergency and non-emergency situations, using the microphone on the unit to send audio, and the nearest speaker to receive audio. The unit could also have a numeric keypad (not illustrated) so that intercom numbers can be dialed.
[0071] FIG. 13 depicts an adaptation of the system of FIG. 1 wherein the personal alarm 5 uses an ultrasonic transducer 410 to transmit encoded information to a nearby receiver. The example personal alarm unit 5 has four switches or pushbuttons S 1 -S 4 , which are labeled, by way of example, FIRE, SECURITY, MEDICAL, and OFFICE. Other functions may be included without departing from the intent and spirit of the invention. When a pushbutton is depressed, the processor 10 retrieves the unique device identification number from memory 20 . The processor subsequently composes a short message containing the device ID and data describing which button was pressed by the user. This message is then encoded by the encoder 25 and transmitted by the transmitter 35 and the ultrasonic transducer 410 .
[0072] The transmitted message is received, processed, and disseminated by the room appliance 480 as shown in FIG. 14 . The ultrasonic transducer 415 receives the transmitted signal. The signal is decoded by the decoder 420 and interpreted by processor 425 . The processor then composes a short message containing the identification number transmitted by the personal alarm, the location of the receiving appliance, and where applicable, the type of message transmitted. The message may be sent to a number of appropriate monitoring stations anywhere on the network.
[0073] Optionally, the room appliance may contain a variety of related devices and functions as described more fully in my aforementioned co-pending application entitled: Networked Room Appliance. For example, the appliance 480 includes a motion detector 435 and a smoke detector 440 . Conditions detected by these detectors, such as a fire or a motion detected after hours, are sent to the processor 425 which then generates a signal for alerting an appropriate monitoring station 490 or 495 via the network interface 430 and the network 485 . A video camera 445 and encoder 450 may be commanded to capture and transmit visual images from the room to the monitoring stations 490 or 495 . The microphone 455 and associated audio encoder 460 may be commanded to capture ambient sounds and likewise transmit them to the monitoring stations 490 and/or 495 . Conversely, the user at monitoring station 490 or 495 may speak to occupants of the room via the intervening network 485 , processor 425 , audio decoder 470 and loudspeaker 465 . The appliance 480 may also contain an information display 475 capable of displaying useful information generated by a device on the network or by a monitoring station 490 or 495 . A common use of the display 475 would be a simple time-of-day clock.
[0074] FIG. 15 depicts operation of the system. A user 565 presses a pushbutton on the personal alarm unit 510 . The personal alarm composes and transmits the appropriate message, which is received and decoded by appliance 500 .
[0075] The appliance 500 forwards the message in a manner appropriate for the type of condition or emergency, as defined by the specific pushbutton activated on the alarm unit 510 . For example, if the user 5654 pressed the FIRE pushbutton, the appliance will notify the fire department 540 and the signal will identify the location of the of the person reporting the fire as well as the identity of the personal alarm unit sending the message via signals sent over the intervening network 570 . The appliance additionally may enable the microphone and/or video camera housed within the appliance 500 , permitting the fire department to further evaluate the nature and magnitude of the emergency.
[0076] If the user 565 pressed the MEDICAL pushbutton, the appliance 500 alerts the nurse station 520 of the location and identity of the user, again via the intervening network 570 . Similarly, the office 535 may be notified and/or the guard station 545 . In each case, the location and identity of the sender is transmitted to the appropriate monitoring stations. The audio and video capability of the room appliance will also permit further verification of the user and further audio with which to evaluate the extent of the emergency, which is to be handled.
[0077] In the embodiment shown the guard station 545 is equipped with several additional enhancements, including the microphone 555 , the push-to-talk switch 550 , and the speaker 560 . When the guard station 545 receives a personal alert alarm signal, the microphone of appliance 500 may be remotely activated, permitting the guard station to monitor audio signals in the vicinity of the appliance for further evaluation of the events. The guard station personnel may also audibly communicate with personnel in the room using the push-to-talk feature and station microphone 555 . The system would route the push-to-talk audio form the station microphone to one or more appliances such as 500 that are in the immediate area of the personal alert unit. Any of the messages generated by the appliance 500 may also be transmitted to a server 515 for archival and logging functions, as well as audio and commands generated by responding guard stations, fire stations, or other stations.
[0078] The various guard stations and other stations with microphones may also have “voice activated” push to-talk-which would automatically, based on voice level and/or duration criteria, generate the push-to-talk signals which would open up the microphone to be transmitted to the selected speaker(s) on various room appliances. For this invention, “push-to-talk” is defined as being either manual switch pushes such as on a microphone button or a computer mouse switch, or voice activated switching.
[0079] While certain features and embodiments of the invention have been described in detail herein, it will be readily understood that the invention includes all modifications and enhancements within the scope and spirit of the following claims. | A personal alarm system can be worn or carried by the user, may be activated at any time by the user and/or may be automatically activated to send a signal to any remote monitoring station on the network. The device identifies the user as well as the user's location within the monitored area. The alarm-sending unit is designed to fit within a box the size of a small cell phone or pager. The unit includes an ID memory for identifying the user, is programmable and has an on-board processor for generating a signal to a wireless transmitter for sending the signal to a to a local receiver for inputting the signal onto the network. A centralized, networked RF receiver is used with the personal alarm unit and one or more of these RF receivers may be installed in order to provided adequate coverage of the monitored area. The signals generated by the personal alarm are received by the RF receiver(s) and decoded, whereupon the system processor assembles a message, packetizes it as necessary, and sends it to one or more monitoring stations via the intervening network and network interface. The signals may be digitized where desired. A beacon generator may be used to identify location of the portable unit. The system may also employ a GPS generator to identify location. | 6 |
This is the natural phase of PCT/EP98/00980, filed 2/20/1998, now WO 98/39339.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to novel aluminum salts of alkyl-(1-alkoxyethyl)-phosphinic acids, their preparation and their use as flame retardants.
2. Description of the Prior Art
Polymers are frequently made flame retardant by adding to them phosphorus-containing or halogen-containing compounds or mixtures thereof. Some polymers are processed at high temperatures, e.g. at 250° C. or above. For this reason, many known flame retardants are not suitable for such applications, because they are too volatile or are not sufficiently heat-stable.
Alkali metal salts of dialkylphosphinic acids are thermally stable and are already proposed as flame retardant additives for polyester (DE-A1-2 252 258). They must be introduced in amounts of up to 30% by weight and some have an adverse corrosion-promoting effect on the processing machinery.
Furthermore, the salts of dialkylphosphinic acids with an alkali metal or a metal from the second or third main group or subgroup of the Periodic Table of the Elements have been used for the preparation of flame-resistant polyamide molding compositions, in particular the zinc salts (DE-A1-2 447 727). Low-flammability thermoplastics may also be prepared by using said salts of phosphinic acids in combination with nitrogen bases such as melamine, dicyandiamide or guanidine (DE-A1-28 27 867).
A further large class of salts of phosphinic acid are the polymeric metal phosphinates. These are nonionic coordination complexes and are soluble in organic solvents. They are suitable as flame retardant components for halogenated aromatic polymers and for polyesters (U.S. Pat. Nos. 4,078,016; 4,180,495), polyamides (U.S. Pat. No. 4,208,321) and polyester/polyamides (U.S. Pat. No. 4,208,322).
Dialkylphosphinic acids are prepared by free-radically catalyzed addition of olefins onto phosphonous acid monoesters and the subsequent hydrolysis of the dialkylphosphinic esters thus produced. Monoesters of phosphonous acid are produced from phosphonous acids. These are obtained by hydrolysis of dichlorophosphines. The processes are technically complex and proceed over a plurality of stages. Industrially simple preparation processes for salts of phosphinic acids which start from dichlorophosphines are therefore sought.
SUMMARY OF THE INVENTION
The object is achieved by novel aluminum salts of alkyl-(1-alkoxyethyl)-phosphinic acids of the formula (I)
where R 1 is an unbranched or branched alkyl radical having 1 to 6 carbon atoms, preferably methyl, ethyl, n-propyl, isopropyl, n-butyl or tert-butyl, and R 2 is an unbranched or branched alkyl radical having 1 to 4 carbon atoms, preferably methyl or ethyl, and a process for preparing the aluminum salts of the formula (I), which comprises reacting alkyl-(1-alkoxyethyl)phosphinic acids of the formula (II)
with aluminum hydroxide in a molar ratio of approximately 3:1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The phosphinic acids of the formula (II) are prepared by known methods from alkyldichlorophosphines and acetaldehyde diacetals (V.S. Tsivunin et al., Zh. Obshch. Khim. 40 (102) 1970, 12, 2560 (1970).
For example, alkyldichlorophosphine is reacted with acetaldehyde diacetal to give alkyl-(1-alkoxyethyl)phosphinic chloride, which is then hydrolyzed to give the corresponding phosphinic acid. The phosphinic acids formed are then reacted in a known manner (EP-A-699 708) with aluminum hydroxide in a molar ratio of 3:1. In this reaction the phosphinic acid and the aluminum hydroxide are stirred in water at 80-100° C. until the aluminum phosphinate according to the invention has been formed virtually quantitatively. Preferably, the reaction is carried out in suitable solvents or solvent mixtures, e.g. in glacial acetic acid. To reduce the duration of the reaction, it is also possible to carry out the preparation of the salts of phosphinic acid according to the invention under pressure at temperatures of 110-250° C.
The salts of phosphinic acid, after drying well, preferably under reduced pressure at temperatures of 150-200° C., are used as flame retardants for polymer molding compositions, e.g. for polyesters such as poly(butylene terephthalate).
Polyesters are polymers which contain repeating units bound via an ester group in the polymer chain. Polyesters which can be used according to the invention are described, for example, in “Ullmann's encyclopedia of industrial chemistry”, ed. Barbara Eivers, Vol. A21, Chapter ‘Polyesters’ (pp. 227-251), VCH, Weinheim-Basle-Cambridge-New York 1992, which is incorporated herein by reference.
The amount of the salt of phosphinic acid of the formula (I) to be added to the polymer can vary within broad limits. Generally, 5 to 30% by weight are used, based on the polymer. The optimum amount depends on the nature of the polymer and on the type of the salt of phosphinic acid used and can readily be determined by experiments.
The salts of phosphinic acid according to the invention can be used in various physical forms, depending on the type of the polymer used and on the desired properties. Thus, for example to achieve an enhanced dispersion in the polymer, the salts of phosphinic acid can be ground to give a finely particulate form. If desired, mixtures of different salts of phosphinic acid can also be used.
The salts of phosphinic acid according to the invention are thermally stable, and neither decompose the polymers during processing nor affect the production process of the polyester molding composition. The salts of phosphinic acid are not volatile under preparation and processing conditions for polymers.
The salt of phosphinic acid can be incorporated into the polymer by mixing the two and then melting the polymer in a compounding unit (e.g. in a twin-screw extruder) and homogenizing the salt of phosphinic acid in the polymer melt. The melt can be taken off as extrudate, cooled and granulated. The salt of phosphinic acid can also be metered directly into the compounding unit.
It is also possible to admix the flame-retardant additives to finished polyester granules and process the mixture directly on an injection molding machine or to melt the flame-resistant additives in advance in an extruder, to granulate them and process them after a drying process.
The flame-retardant additive can also be added during the polycondensation. In addition to salts of phosphinic acid according to the invention, fillers and reinforcing agents such as glass fibers, glass beads or minerals such as chalk can be added to the formulations. In addition, the products can comprise other additives, such as stabilizers, lubricants, colorants, nucleating agents or antistatics.
The low-flammabiiity polyesters according to the invention are suitable for the preparation of shaped bodies, films, filaments and fibers, e.g. by injection molding, extrusion or pressing.
EXAMPLES
1. Preparation of 1-methoxyethyl(methyl)phosphinic Acid
1.1. Preparation of the acid chloride
649 g (5.55 mol) of dichloromethylphosphine were heated to 30° C. and 500 g (5.55 mol) of acetaldehyde dimethyl acetal were added dropwise at 30-40° C. in the course of 3.5 hours with stirring and cooling. In the course of this, methyl chloride was formed vigorously. After completion of gas formation, the mixture was heated briefly to 60° C., then cooled and stirred further. The mixture was then distilled. 548 g of 1-methoxyethyl(methyl)phosphinic chloride were obtained at a boiling temperature of 63° C. at 0.25 mbar. This corresponds to a yield of 64% of theory.
1.2. Preparation of the Acid
126.1 g (7 mol) of water were added carefully dropwise with cooling and stirring to 547.6 g (3.5 mol) of 1-methoxyethyl(methyl)-phosphinic chloride. After addition was complete, the mixture was agitated at room temperature and then distilled. 471 g were obtained at a boiling temperature of 135-138° C. at 0.1 mbar. This corresponds to a yield of 97.5% of theory.
2. Preparation of the Aluminum salt of 1-methoxyethyl(methyl)-phosphinic Acid
345 g (2.5 mol) of 1-methoxyethyl(methyl)phosphinic acid were dissolved in 1.2 l of water and stirred with 65 g (0.83 mol) of aluminum hydroxide for 72 hours at 80-90° C. The mixture was filtered off using suction, washed with water and dried at 0.5 mbar, initially at 80° C. and then at 180° C. 334 g of a white powder which does not melt at 350° C. were obtained. This corresponds to a yield of 92% of theory.
Result of elemental analysis:
C 12 H 30 AIO 9 P 3 (438)
calculated:
32.9% C
6.85% H
6.17% AI
21.23% P
found:
33.0% C
7.05% H
5.9% AI
20.9% P
3. Preparation of 1-ethoxyethyl(methyl)phosphinic acid
3.1. Preparation of the Acid Chloride
96.1 g (0.82 mol) of dichloromethylphosphine were cooled to −20° C. and 97 g (0.82 mol) of acetaldehyde diethyl acetal were added dropwise in the course of 3.5 hours with stirring and constant cooling. After dropwise addition was complete, the mixture was allowed to come to room temperature and was further stirred for two hours. The mixture was then distilled. 87 g of 1-ethoxyethyl(methyl)-phosphinic chloride were obtained at a boiling temperature of 65° C. at 0.75 mbar. This corresponds to a yield of 62% of theory.
3.2. Preparation of the Acid
18 g (1.0 mol) of water were carefully added dropwise to 34 g (0.2 mol) of 1-ethoxyethyl(methyl)phosphinic chloride at 10° C. with cooling and stirring. After addition was complete, the mixture was further stirred for one hour at room temperature and then distilled. 29.5 g were obtained at a boiling temperature of 136-138° C. at 0.35 mbar. This corresponds to a yield of 97% of theory.
4. Preparation of the Aluminum salt of 1-ethoxyethyl(methyl)phosphinic Acid
297 g (1.95 mol) of 1-ethoxyethyl(methyl)phosphinic acid and 50.7 g (0.65 mol) of aluminum hydroxide were stirred in 1.2 l of water for 75 hours at 80-90° C. The mixture was then filtered off using suction, rinsed with water and dried at 0.5 mbar, initially at 80° C. then at 180° C. 265 g of a white powder having a residual water content of 0.06% were obtained. The melting point is above 350° C. This corresponds to a yield of 85% of theory.
Result of elemental analysis:
C 15 H 36 AIO 9 P 3 (480)
calculated:
37.5% C
7.5% H
5.69% AI
19.38% P
found:
36.9% C
7.4% H
5.5% AI
19.4% P
5. Preparation of 1-methoxyethyl(ethyl)phosphinic Acid
5.1. Preparation of the acid chloride
143.8 g (1.098 mol) of dichloroethylphosphine were cooled to −10 to 15° C. and 99 g (1.099 mol) of acetaldehyde dimethyl acetal were added dropwise in the course of 90 minutes. The mixture was allowed to come to room temperature slowly. It was then further stirred for 24 hours and then distilled. 119 g of 1-methoxyethyl-(ethyl)ethylphosphinic chloride were obtained at a boiling temperature of 69° C. at 0.6 mbar. This corresponds to a yield of 60% of theory.
5.2. The acid was prepared in a similar manner to the instructions of 1.2 1-Methoxyethyl(ethyl)phosphinic acid having a boiling point of 146-151° C. at 0.25 mbar were obtained in approximately 95% yield.
6. Preparation of the Aluminum Salt of 1-methoxyethyl(ethyl)phosphinic Acid
127 g (0.84 mol) of 1-methoxyethyl(ethyl)phosphinic acid were stirred in 400 ml of water with 21.7 g (0.278 mol) of aluminum hydroxide for 72 hours at 80-90° C. The mixture was then filtered off using suction, washed with water and dried at 0.5 mbar, initially at 80° C. then at 180° C. 96 g of a white powder which does not melt at up to 350° C. were obtained. This corresponds to a yield of 72% of theory.
Result of elemental analysis:
C 15 H 36 AIO 9 P 3 (480)
calculated:
37.5% C
7.5% H
5.63% AI
19.38% P
found:
37.5 %C
7.1% H
5.3% AI
20.0% P
7. Use Example
From the aluminum salt of 1-methoxyethyl(methyl)phosphinic acid, prepared as described in Example 2, and poly(butylene terephthalate), compounds reinforced with 30% glass fibers were produced without other additives, test pieces of thickness 1.5 mm were extruded and tested with the following result:
Concentration
Flammability rating
%
UL 94
20
V1 | Aluminum salts of alky-(1-alkoxyethyl)phosphinic acids are prepared by reacting alky-(1-alkoxyethyl)phospihnic acids with aluminum hydroxide in a molar ratio of 3:1. The resulting aluminum phosphinates are used as flame retardants in thermoplastics, particularly in polyesters. | 2 |
SUMMARY OF THE INVENTION
This invention relates to mowing machines.
According to the present invention there is provided a mowing machine with a number of mowing elements arranged in a row near each other, each mowing element comprising at least one pivotably mounted cutting member; there being a gear wheel housing mounted below said mowing elements and the pivot axis of each cutting member, as seen from above, being inside the circumference of a gear wheel driving the corresponding mowing element.
For a better understanding of the invention and to show how the same way be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a mowing machine shown attached to the lifting device of a tractor;
FIG. 2 is a rear view of part of the mowing machine of FIG. 2 taken on the line II--II in FIG. 1 and on a larger scale;
FIG. 3 is an enlarged plan view of part of the machine,
FIG. 4 is an enlarged sectional view taken on the line IV--IV in FIG. 3;
FIG. 5 is a view from the rear of a detail, taken at V--V in FIG. 3;
FIG. 6 is an enlarged detail view in the direction of arrow VI in FIG. 1 of part of a swath building device of the mowing machine;
FIG. 7 shows the same part of the mowing machine as FIG. 2 but in a different position;
FIG. 8 is a sectional view (similar to FIG. 4 but illustrating an alternative form of mowing machine;
FIG. 9 is a rear view of an alternative form of mowing machine, this form being equipped with a screening device; and
FIG. 10 is a sectional view taken on the line X--X in FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1 the mowing machine shown has a cutter bar 1 shown in the Figure connected by means of an intermediate frame 2 and a three-point trestle 3 with the three-point lifting device 4 at the rear (with respect to the direction of operative travel A over the ground) of a tractor 5. The three-point trestle 3 includes (see also FIG. 2) two upwardly converging frame members 7 extending from a horizontal supporting beam 6 and having, near the top, parallel ears 8 providing the means for attachment to the top rod 9 of the three-point lifting device 4. The supporting beam 6 is furthermore provided at both ends with pins 10 for coupling to the two lifting arms 11 of the three-point lifting device 4.
At the rear the three-point trestle 3 has rigidly secured thereto a hollow beam 12 extending parallel to the supporting beam 6 and connected with the rear edge portions of the frame members 7, this beam 12 being located substantially midway of the distance between the supporting beam 6 and the ears 8, see FIG. 2. The lower side of the supporting beam 6 is provided near one end with a support 13 mounting a horizontal pivot shaft 14 extending in the direction of travel A and consisting of a substantially hollow, tubular member. Pivotable about the pivot shaft 14 is a supporting beam 15 constructed, viewed in plan, of two longitudinally spaced beams 15A and 15B extending transversely of the direction of travel A and interconnected by intermediate parts 15C, 15D and 15E of which the intermediate parts 15C and 15D are near the ends and the part 15E is in the proximity of the pivot shaft 14 approximately at the level of the end of the supporting beam 6. The part 15E constitutes a stiffening member. The supporting beam 15 constitutes the main part of the intermediate frame 2 and is, therefore, comparatively heavy.
As shown in FIG. 2 the hollow beam 12 is provided near a free end of the supporting beam 15 with a buffer 16, which is variable in length and is provided with a stop 17 the distance of which from the hollow beam 12 is adjustable by placing a pin in a selected one of a plurality of bores 18. The buffer 16 limites pivotal movement of the supporting beam 15.
At the end remote from the three-point trestle 3 the supporting beam 5 is pivotally connected by means of a horizontal pivot shaft 19, extending in the direction of travel A, with a support 20 having a U-shaped form viewed in plan, the web and the limbs of which extend vertically a selected. As shown in FIG. 2 the web occupies a substantially vertical position. Near the top the limbs of support 20 are transversed by a pivot shaft 21 which is connected with an arm 22 near the end thereof front with respect to the direction of travel A. The arm 22 is made up of two portions 23 and 24 and is adapted to turn, at the end remote from the pivot shaft 21, about a pivot shaft 25 connected with the hollow beam 12. The pivot shafts 14, 19, 21 and 25 are located at the corners of a parallelogram. The arm portions 23 and 24 are relatively pivotable about a pivot shaft 26, relative pivotal movement of these two portions being limited on one direction by stop lugs 27 and 28 on the portion 23 and 24 respectively. Therefore, the pivot shaft 26 can move with respect to the supporting beam 15 only over a limited distance. As is shown in FIG. 2, the arm portions 23 and 24 are, in the operational state, at an angle of less than 10° to one another.
The supporting beam 15 has a bore 29 for cooperation with a locking pin 30 inserted in support 20. In this way support 20 can be fixed in a transport position relative to the supporting beam 15, as will be described later with reference to FIG. 7.
On the side remote from the intermediate frame 2 support 20 is connected via a flat frame beam 32 with a gear trough 31 which is covered on its top by flat frame beam 32. As is shown in FIG. 4, the frame beam 32 serves not only as a cover for the trough 31 but also as a support for a large number in the machine illustrated sixteen - of mowing elements or cutting members 33. The gear trough 31 consists of a plurality of releasable gear boxes 34, each of which surrounds four pinions 51 for rotating four cutting members 33. Each gear box preferably has a length of about forty centimeters. As shown in the plan view of FIG. 3 each gear box 34 has a scalloped edge portion at the front and is straight at the rear. The operative part of each cutting member projects forwardly of its gear box, whereas it does not project beyond the rear edge of the gear box.
As shown in FIG. 5, neighboring gear boxes 34 are provided with flanges 35 fastened to one another by bolts 36. It is preferred to sandwich a packing of, for example, teflon between the flanges 35. The portion of the gear trough 31 connected with support 20 is formed by a gear box 34A which is widened rearwardly in the proximity of the supporting part 20 (see FIG. 1). The web of support 20 carries a gear box 37 containing a 90° pinion transmission including a comparatively large bevel pinion 38 and a smaller bevel pinion 39 (FIG. 2). The pinion 38 is on a shaft 40 which extends through the web of support 20 and is provided at the end remote from the pinion 38 with splines. The shaft 40 is thus connectable with a universal auxiliary shaft 41, which can follow the deflections of the cutter bar 1 by means of universal joints.
The auxiliary shaft 41 is coupled at the end remote from the shaft 40 with an output shaft 42 of a gear box 43. The gear box 43 contains mainly two meshing pinions 44 and 45 having a comparatively small diameter and a comparatively large diameter respectively. In order to obtain the desired number of revolutions of the cutting member 33 the pinions 44 and 45 may be selected accordingly. The shaft 42 is coupled by means of a bevel pinion 46 with the pinions 44 and 45. The gear box 43 is bolted to the top of the supporting beam 15, as shown in FIG. 2, between the part 15C and the pivot shaft 14. The pinion 45 is on a horizontal shaft 47, extending in the direction of travel A and projecting out of the gear box 43 both at the front and at the rear. At the front of the gear box 43 the shaft 47 is coupled in a manner not shown through a universal auxiliary shaft with the power take-off shaft of the tractor 5. At the rear the shaft 47 is available for driving an additional implement.
The bottom of gear box 37 is disposed at a small distance above the cover 32 so that space is left between the top of the cover-forming frame beam 32 and the bottom of the gear box 37, in which space the cutting member 33 adjacent support 20 rotates. The pinion 39 is on a shaft 48 which is screened by a sleeve 49 in the space between the box 37 and the frame beam 32.
The shaft 48 extends into the gear box 34A, where it carries a pinion 50 (FIG. 1). The pinion 50 is drivably in mesh with a pinion 51 (FIG. 4). The pinion 51 is the first pinion of a large sequence of preferably spare gears which are all disposed in the gear trough 31. The diameter of the addendum circle of these pinions amounts to about 10.5 centimeters. The pinions 51 are cylindrical with hollow centers. Each pinion 51 has its bottom face connected, by means of a number of countersunk or recessed head screws 52, with the top face of a ground or base plate 53 having a circular shape viewed in plan. This base plate 53 is rigidly secured, for example, by casting or welding, to a rotor shaft or stub shaft 54 (FIG. 4). By means of bearings 56 and 57 at the top and bottom respectively the stub shaft 54 is rotatable about a rotary axis 55 in a bearing support 58. Bearing support 58 is connected by bolts 59 with the bottom of the frame beam 32. In this way each pinion 51 is suspended from the frame beam 32.
As already stated, the frame beam 32 covers the four gear boxes 34 and 34A. The rear of the frame beam 32 is connected with the gear trough 31 by means of bolts 59 (FIG. 4), the head of each bolt being countersunk in the frame beam 32. At the front bolts 60 establish the connection between the frame beam 32 and the trough 31. As shown in FIGS. 3 and 5, the bolts 59 and 60 are also arranged in close proximity to one another between two adjacent gear boxes 34. For sealing purposes a packing of, for example, teflon is provided between the frame beam 32 and the trough 31.
With the described disposition of the cutting members 33 the distance between neighboring rotary axes 55 amounts to about ten centimeters. The space enclosed in the gear box 34 or 34A located beneath each cutting member 33 is preferably such that the pinion 51 associated with the cutting member is fairly intimately embraced, that is there is little free space around each pinion 51.
Neighboring cutting members rotate in opposite senses as indicated by arrows B and C in FIG. 3. Each cutting member 33 is fastened by means of a fixing pin 61 to the associated stub shaft 54. Each cutting member 33 consists of a rotor 62 formed by a strip that is wedge-shaped in section as shown in FIG. 4. The lower face of the rotor 62 is parallel to the top face of the frame beam 32, whereas the top face is at an acute angle of, preferably, less than 10° and more preferably about 8° to the top face of the frame beam 32. Near one end each rotor 62 has a pin 63 at right angles to its top surface, the extended axis of pin 53 intersects the extended rotor axis 55 at a small acute angle which is, in the machine illustrated, about 4°. The pin 63 is provided on the side facing the rotary axis 55 with a projection or cam 64. The pin 63 pivotably supports a cutter formed by an elongate blade 65.
Viewed in plan (FIG. 3) and in the sectional view of FIG. 4 the part of the rotor 62 remote from the cutter 65 is thickened and widened to serve as a counter-weight 66. In order to fasten the cutter 65 to the pin 63 it has a slot 67 corresponding to the cam 64 so that by turning it through 180° the cutter can be mounted on, or removed from, the pin 63.
The cutter 65 extends to such a distance beyond the front edge of the frame beam 32 that neighboring cutters 65 can overlap in the vicinity of the narrowest part of the trough 31, viewed in the direction of travel A. As clearly shown in FIG. 3 immediately adjacent rotors are angularly displaced relatively to one another by 90°. The resulting 90° off-set of adjacent cutters 65 (FIG. 3) provides, in addition, a large overlap region. Each cutter 65 preferably has a slightly trapezoidal shape as viewed in plan such that near the end remote from the pin 63 the cutter 65 has a larger width than at the end nearest the rotary axis 55. Each cutter 65 is preferably parallel to the top face of the rotor 62. The position and the length of each cutter 65 with respect to its pin 63 are such that the cutter 65 preferably does not intersect the prolongation of the top surface of the frame beam 32. The largest dimension of the rotor 62 is preferably smaller than the diameter of the addendum circle of its pinion 51. In a direction parallel to the top surface of the frame beam 32 this largest dimension amounts to about nine centimeters. The length of the cutter 65 is preferably chosen as that the cutter projects over a distance of about two centimeters in front of the front of the gear trough 31. The pivot axis (that is the axis of the pin 63) of each cutter 62 is inside the circumference of the pinion 51 that drives the cutting member 33 that carries the cutter 62.
The end of the cutter bar 1 remote from the intermediate frame 2 is provided with a swath building device 68 that includes four rake wheels 69, 70, 71 and 72 having the lowermost points of their peripheries at substantially equal distances from the ground. These rake wheels (see FIG. 1) are arranged in a row and overlapping one another at least partly. The diameter of the foremost rake wheel 72 with respect to the direction of travel A is smaller than the diameter of the next rake wheel 71 and so on, the diameters of the four rake wheels 69 and 72 differing to an extent such that the diameter of each rake wheel is about 25% smaller than that of the next-following rake wheel. Each rake wheel is formed by a swath board, the outer rim of which is bent over towards the cutter bar and is provided with regular notches (FIG. 6). The notches have a sawtooth shape, the teeth formed at the periphery extending rearwardly viewed in the direction of rotation D of the rake wheel in operation. The rake wheels are each fastened to a shaft 73, 74, 75 and 76 respectively, these shafts being parallel to one another and trailing at an acute angle of preferably about 50° to 60° to the direction of travel A. Viewed in a direction parallel to the shafts 73 to 76 each rake wheel overlaps by about 25% of the diameter of the next-following rake wheel. The shafts 73 and 76 are fastened to a carrier 77 inclined upwardly away from the cutter bar 1 and pivotable to a limited extent with respect to the cutter bar 1 about a horizontal pivot shaft 78. The pivot shaft 78 preferably extends parallel to the shafts 73 to 76. The pivot shaft 78 is connected with a lug 79 which is pivotable about a substantially vertical pivot shaft 80 and is connected with the rear of the external part of the cutter bar 1. In the outward direction with respect to the intermediate frame 2 turning of the lug 79 about the shaft 80 is limited by a stop part 81 of the frame beam 32.
The mowing machine described above operates as follows.
During operation the mowing machine is suspended from the three-point lifting device 4 of the tractor 5 and in the operational state the intermediate frame 2 occupies the position shown in FIG. 2. The power take-off shaft of the tractor drives the pinions 51 within gear box 43, the auxiliary shaft 41 and the gears or pinions 38, 39, and 50 so that with the illustrated disposition of the cutting member 33 the neighboring cutting members are driven in opposite senses B and C. The construction of the cutting members shown in FIG. 4 requires that each pinion in the trough 31 is directly coupled with the superjacent cutting member 33. The results in a simple and extremely effective assembly, in which the space between each cutting member and its pinion is utilized for sealing the trough 31 by means of the cover-forming frame beam 32. This beam 32 serves as a main carrier for the cutter bar 1 and therefore is a rigid structure. By the mode of fastening of the stub shaft 54 the cutting member is fastened to the frame beam 32. By its connection with the stub shaft 54 each pinion 51 is also connected with the frame beam 32. Thus the trough 31 only serves for accommodating the pinions 51 so that it can be of comparatively simple and light-weight structure. The trough 31 is composed of sections formed by the gear boxes 34 and 34A, each holding four cutting members. In this way a trough is formed which can be readily replaced in parts, which may be important when, for example, the bottom of a gear box has worn out or when the through and/or the pinions have been damaged. Since each gear box has a fixed length corresponding to the dimension of the frame beam 32, a satisfactory seal is obtained between the gear boxes and the frame beam 32.
Since each cutting member 33 has only one cutter 65 double cutting is minimized yet a satisfactory overlap is obtained. The inclined position of the cutter 65 with respect to the top surface of the frame beam 32 is advantageous for cutting at a level near the ground and in conjunction with the upwardly inclined rotors 33 adjacent thereto it improves the delivery of the cut crop. Owing to the very small distance between the rotary axes 55, which distance is preferably about ten centimeters, pinions of small diameter may be employed, while in addition the front of the cutter bar 1 may have a scalloped shape so that a regular mowing effect can be ensured throughout the width of the cutter bar 1. The low weight of the small cutting elements means that the mower can be moved with comparatively high speed while satisfactory ground contact is maintained. If desired, the cutting level of the cutting member 65 can be adjusted by adjusting the top rod 9 of the lifting device 4.
The construction described above avoids the use of intermediate pinions or shafts or both so that it can be compact. The composition of the mowing machine by substantially identical modules matches the present-day efficiency requirements. Owing to the comparatively low weight of the cutting members and the pinions it is possible to use comparatively very high speed cutting members, which speed can be raised by the gear boxes 43 and 37 from 540 rev/min of the power take-off shaft to preferably about 10,000 rev/min.
The swath building device 68 permits not only of clearing a strip of ground to obtain a separation between the cut and deposited crop and the standing crop in the next run but also of obtaining an airy swath. For this purpose the disposition of the rake wheels 69 to 72 is very important. Since the rake wheels are at a given distance above the ground on the carrier 77, the rake wheels are struck by the stream of crop near the top, while the top of each rake wheel rotates in the direction of the arrow D, which gives a movement of the top of the rake wheels to the rear. Thus the crop is constantly raised in the rearward direction so that the crop can be deposited in a very airy state. In order to ensure a satisfactory grip on the crop the rake wheels preferably have their edge near the circumference bent over towards the cutter bar 1. Owing to the orientation of the teeth in the direction of rotation D the teeth will readily disengage the crop.
The parallelogram structure of the intermediate frame 2 permits the cutter bar 1 to respond smoothly to unevennesses of the ground during operation, on the one hand by pivotal motion of the portions of the arm 22 about the pivot shaft 26. The cutter bar can be set in a plurality of positions by means of the buffer 16. This may be important, for example, for cutting at a desired height above the ground surface of for mowing on a sloping surface.
FIG. 7 shown a transport position of the mower, in which by means of the locking pin 30 at the cutter bar 1 is fixedly connected with the intermediate frame. In this position of pivot shaft 26 has moved over a predetermined distance in a direction of height. The supporting beam 15 extends substantially horizontally in this position and this position is fixed by the buffer 16. If desired, the buffer 16 may as an alternative, be formed by a hydraulic cylinder suitable for operation by remote control. The open construction of the supporting beam 15 allows the auxiliary shaft 41 during the pivotal movement to move between the portions 15A and 15B to beneath the frame beam (FIG. 7).
FIG. 8 shows a second form of the cutter bar 1 based on the same gear trough 31 closed by the cover-forming frame beam 2. In this form the cutting members 82 are also driven from below by means of pinions 83, each of which specifically serves to drive its associated cutting element 82 in accordance with the structure of the preceding embodiment. In this form the gear trough 31 is formed by gear boxes 84 having each near its center a bearing 85. The bearing 85 holds a shaft 86, which mounts the pinion 83, this shaft extending upwardly from the bearing 85 through the cover-forming frame beam 32. The shaft 86 is journalled in the cover 32 by means of a bearing 87. At the top the shaft 86 is fixedly connected by means of a safety pin 88 with a disc-shaped rotor 89, the bottom of which is substantially parallel to the surface of the frame beam 32. The top surface of the rotor 89 is of a frusto-conical form the cone of which has a half apex smaller than 10° and preferably of 8°. The diameter of the rotor 89 is preferably smaller than the diameter of the addendum circle of the pinion 83. Near the outer edge the rotor 89 has two diametrically disposed pins 90 each having a projection or cam 91 in the manner shown in the preceding form. The pins 90 serve for pivotably supporting the cutters 92, each of which has a slot 93 corresponding to the cam 91 and displaced 180° as seen in FIG. 8. The cutters 92 preferably extend parallel to the associated neighboring surface of the rotor 89. The shape and the length of the cutters 92 correspond with those of the cutters 65 in the first form. Neighboring cutters 92 are relatively off-set through 90°.
The alternative form of the cutting member 82 shown in FIG. 8 is a construction in which the frame beam 32 supports the shaft 86 and also the gear trough 84 has a supporting function. This construction may be advantageous when the shafts 86 have to be supported to the optimum, which may be required for mowing heavy crop. It should be noted, however, that the cover-forming frame beam 32 maintains its supporting function.
FIGS. 9 and 10 show a form in which the cutting members are protected by a screening member 94 at the front and by a screening member 95 on the rear. The screening assembly consisting of members 94 and 95 is only supported by the top of support 20 so that a very ample passage for the crop is obtained. Each screening member consists of a framework 96 holding a screening plate 97. FIG. 10 shows that the screening plate has a substantially zigzag-shaped form. At a distance above the cutting members and also at a distance in front of and behind the cutting members the screening members 94 and 95 respectively are bent over forwardly and rearwardly respectively, while, viewed in the direction of travel A as seen in FIG. 9, the lower edge of the screening member is located just above the cutting members. Each screening member 94 and 95 is pivotable about a pivot shaft 98 and 99 respectively, each of which shafts are supported at the end on the web of support 20.
Angular supports 100 are provided substantially midway the length of the screening members, viewed in a direction parallel to the cutter bar 1. The downwardly extending ends of the angular supports 100 serve to hold two rods 101, each of which is surrounded by a helical spring 102. The rods 101 are pivotable about shafts 103. In this manner each screening member 94 and 95 is resiliently deflectable, while, if desired, stop elements 104 of the rods 101 can limit the amplitude of the deflection.
During operation the screening members 94 and 95 serve as step or guard means against hard objects ejected by the cutting member, and the screening member 94 extending far to the front protects animals tending in a frightened flight to jump against the bent part of the screening member 94. Owing to their resiliently deflectability the screening members have a comparatively stable position, while the zigzag-shaped screening plate is sufficiently rigid to absorb relatively heavy forces.
The shape of the screening members is quite suitable for guiding long stalks on the space between the screening members so that the various stalks can be effectively cut by the cutting member, that is so say without double cuts.
Although various features of the mowing machine described and illustrated in the drawings are set forth in the following claims as inventive features it is to be understood that the invention is not necessarily limited to these features and encompasses all of the features that have been described both individually and in various combinations. | Mowing apparatus for connection to the lifting device of a tractor which is powered by the power take-off of the tractor. The apparatus includes a three-point trestle for mounting on the three-point lift device of the tractor, the trestle supporting a parallelogram suspension gear for the mowing component, a gear box and an intermediate telescopic driving shaft for the mowing elements. The parallelogram has a suspension gear including two foldable arm portions whereby the mowing component can be rotated upwardly for transport. The intermediate drive shaft is connected to the mowing component via a gear box. The mowing component is made up of four gear boxes each holding four side-by-side intermeshing pinions, the four gear boxes being connected by a flat frame beam across the top of same with the pinions of adjacent gear boxes being in mesh. Each pinion is journalled in bearings connected to the frame beam thereby suspending same above the bottom of the gear box. A shaft from the pinion extends upwardly from the gear box to engage a disc with a slanting top side, a cutter being mounted at the lower portion of such disc to extend in front of the frame beam which, at its front edge, is curved to correspond with the underlying pinions. A swathboard at the outer end of the mowing component includes a plurality of rake wheels arranged in echelon having sawtooth-shaped circumferences and becoming progressively larger in diameter to the rear. A carrier for the rake wheels is pivotable within limits about horizontal and vertical axes with respect to the frame beam. A screening member is mounted on the frame beam which extends both in front and to the rear of the cutting component whereby, when seen from the side, it has an inverted wide V-configuration, the screen mechanism being resiliently deflectable. | 0 |
BACKGROUND OF THE INVENTION
The present invention pertains to doppler radars including a transmitter which periodically transmits pulses of electrical energy and a receiver which receives reflected portions of the energy of the transmitted pulses and removes the carrier so that only the change of frequency is available. The signal which is provided by the receiver is referred to in the art as a bipolar video, or reflected, pulse train. In prior art range tracking apparatus the bipolar video pulse train is sampled by a circuit which is controlled by a range gate and the sampled signals are detected and filtered, after which they are used as part of an error signal in a conventional servo loop to control the position of the range gate. The major problem with this system is that the loop becomes unstable if the filter time constants are reduced too far. However, the large time constants of the prior art systems cause range errors which are largely dependent on the velocity or acceleration of targets. It is extremely difficult to design a servo loop which can accurately track wide variations of range, velocity and acceleration, such as missiles passing close to the radar vehicle. Further, the prior art systems are relatively complicated and expensive to produce.
SUMMARY OF THE INVENTION
The present invention pertains to range tracking apparatus in a pulse doppler radar wherein sample and hold means are connected to the radar receiver to provide a doppler signal, which doppler signal is applied to threshold means that apply a signal to range counter means each time the doppler signal exceeds a predetermined threshold and the range counter means control the range position of a gate applied to activate the sample and hold means.
In an embodiment of the present invention, in addition to the above noted apparatus, a second range tracking gate is provided a short time after the start of the first range tracking gate and the second range tracking gate activates a second sample and hold means which supplies a second doppler signal through threshold means to a range counter each time the second doppler signal exceeds a predetermined threshold and the range counter reduces the range of the first gate when the first threshold means applies a signal thereto and increases the range of the first gate when the second threshold means applies a signal thereto with no signal output from the first threshold means.
It is an object of the present invention to provide improved range tracking apparatus for a doppler radar.
It is a further object of the present invention to provide range tracking apparatus for a pulse doppler radar wherein the range of a tracking gate is changed in discrete steps in accordance with the position of the range gate relative to the leading edge of the doppler signal.
These and other objects of this invention will become apparent to those skilled in the art upon consideration of the accompanying specification, claims and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified block diagram of a doppler radar including an embodiment of the present invention, and
FIGS. 2(a), (b), (c) and (d) illustrate various conditions which the tracking apparatus will experience.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring specifically to FIG. 1, a doppler radar transmitter 10 periodically supplies pulses of RF energy to an antenna 11. The frequency of the RF pulses is controlled by a local oscillator 12, which is connected to the transmitter 10. When the pulses of energy transmitted by the antenna 11 are reflected from a moving object, portions of the reflected energy are received by an antenna 13 and supplied to an RF amplifier 14. The signals from the RF amplifer 14 are applied to a mixer 15 and mixed with a signal from the local oscillator 12 to remove the RF and provide an output signal having a frequency proportional to the speed of the target. This signal, which is a train of video or reflected pulses, is amplified in a video amplifier 16 and the amplified signal is available at an output terminal 17. The operation of a pulse doppler radar is well known to those skilled in the art and is illustrated here in very simplified block form only to place the present invention in the proper environment. It will further be understood by those skilled in the art that many variations and alterations of the foregoing are, or may become, available.
The output of the video amplifier 16 at the terminal 17 is applied to inputs of a first sample and hold circuit 20 and a second sample and hold circuit 21. The sample and hold circuit 20 is activated by a range tracking gate which is applied to a gating signal input thereof from a range counter 25. The range counter 25 receives a signal from the transmitter 10 which is indicative of the pulse repetition rate of the transmitter 10 and one tracking gate is produced by the range counter 25 for each pulse of energy transmitted by the transmitter 10. The range tracking gate is produced at some time subsequent to the associated transmitter pulse, which time is dependent upon a setting or count stored in the range counter 25. Initially, the tracking gate supplied to the sample and hold circuit 20 may be produced at some preset value, for example near the outer most end of the range of the doppler radar.
The signals supplied to the sample and hold circuit 20 from the video amplifier 16 are sampled once for each tracking gate applied to the sample and hold circuit 20. It should be understood that, generally, the repetition rate of the transmitter 10 will be high compared to the signal supplied by the video amplifier 16 so that the sample and hold circuit 20 will sample each cycle a plurality of times. The output signal from the sample and hold circuit 20 is applied through a doppler filter 26, which is in general a low pass filter, and the doppler signal available at the output of the filter 26 is applied to one input of a threshold circuit, generally designated 30. In the present embodiment, the threshold circuit 30 includes a comparator 31 and a variable feedback resistor 32, which operates to set the threshold of the circuit. The resistor 32 is connected between fixed power voltage (not shown) and a second input of the comparator 31 so that the output of the doppler filter 26 is always compared to the threshold set by the resistor 32. When the signal at the output of the doppler filter 26 exceeds the predetermined threshold voltage applied to the comparator 31, a signal or pulse is applied to one input of the range counter 25. The range counter 25 generally includes an up/down counter and the output from the threshold circuit 30 is applied to the down input so that each time a pulse is received from the threshold circuit 30 the range counter 25 reduces the range of the tracking gate applied to the sample and hold circuit 20 by one increment. The increments or steps of range through which the tracking gate applied to the sample and hold circuit 20 is controlled are sufficiently small so that no loss of accuracy of the doppler radar is noticeable as compared to a prior art continuous tracking conventional servo loop.
The gate from the range counter 25 is also applied through a delay circuit 35 to a gating signal input of the second sample and hold circuit 21. The output signal from the sample and hold circuit 21 is applied through a second doppler filter 36 to an input of a threshold circuit generally designated 37, which includes a comparator 38 and a variable threshold resistor 39 connected between a fixed voltage (not shown) and to a second input of the comparator 38. The sample and hold circuit 21, doppler filter 36, and threshold circuit 37 operate in a fashion similar to that described for the sample and hold circuit 20, doppler filter 26, and threshold circuit 30.
The delayed gate from the delay circuit 35 activates the sample and hold circuit 21 so that a sample is taken of the signal from the video amplifier 16 each time the gate appears. The tracking gate is delayed by the delayed circuit 35 so that the leading edge of the tracking gate applied to the sample and hold circuit 21 occurs subsequent to the leading edge of the tracking gate applied to the sample and hold circuit 20, but generally prior to the trailing edge of the gate applied to the sample and hold circuit 20. In the present embodiment, for example, the second tracking gate is delayed a time equal to approximately one-half of the width of the first tracking gate. Doppler signals applied to the threshold circuit 37 which exceed the predetermined threshold set by the variable resistor 39 supply a signal or pulse to one input of an inhibit circuit 40. A second input of the inhibit circuit 40 is connected to the output of the first threshold circuit 30 and an output of the inhibit circuit 40 is connected to a second input (the up input) of the range counter 25. When a signal is prevelant at the output of the threshold circuit 30, the inhibit circuit 40 prevents the application of signals from the output of the threshold circuit 37 to the second input of the range counter 25. When no signals are present at the output of the threshold circuit 30 but signals are present at the output of the threshold circuit 37, these signals are applied to the second input of the range counter 25 to increase the range of the tracking gate provided by the range counter 25. Since the tracking gates applied to both sample and hold circuits 20 and 21 are generated from the range counter 25, an increase or decrease in range will affect both tracking gates.
FIG. 2(a), (b), (c) and (d) indicate the various conditions which the range tracking apparatus will experience as a reflected pulse appears at approximately the same range as the tracking gates. For convenience, the tracking gate applied to the sample and hold circuit 20 is referred to as an "early gate" and the tracking gate applied from the delay circuit 35 to the sample and hold circuit 21 is referred to as a "late gate" . In FIG. 2(a) a reflected pulse has a greater range than either of the early or late gates. At this time, there is insufficient signal level in either gate position to develop an error signal at the output of the threshold circuits 30 or 37 and, therefore, both the early and late gates will remain stationery at there present range. If the target moves away from the radar the reflected pulse will move further out in range and will not be tracked. If the target moves toward the radar the following sequence of events will occur. In FIG. 2(b) the signal in the late gate channel (sample and hold circuit 21, doppler filter 36 and threshold circuit 37) has just overcome the threshold level set by the resistor 39 in the threshold circuit 37. This condition results in an error signal being gated to the range counter 25 to step the tracking gates out in range to meet the incoming pulse. This situation will continue until the signal in the early gate channel (sample and hold circuit 20, doppler filter 26, and threshold circuit 30) also exceeds the threshold set by the resistor 32 in the threshold circuit 30.
In FIG. 2(c) the signal level in the early gate channel has just crossed the threshold set by the resistor 32 in the threshold circuit 30. This condition causes the error signal from the early gate channel to assume control, that is, the output from the threshold circuit 30 will activate the inhibit circuit 40 to prevent the output from the threshold circuit 37 from reaching the range counter 25. Also, the error signal from the threshold circuit 30, or the early gate channel, causes the range counter 25 to step the tracking gates to the left in FIG. 2, or decrease the range, at a rate related to the doppler frequency. This condition will prevail until the position of the early gate moves along the leading edge of the reflected pulse to a point where the signal level in the early gate channel crosses below the threshold and the late gate channel again takes over as shown in FIG. 2(b). Thus, the early gate will effectively dither about the location of the threshold of the reflected pulse and accurately track the pulse as it progresses in either direction, once the threshold has been exceeded for either of the gates. The doppler signal frequency from the doppler filters 26 and 36 is directly proportional to the relative radial velocity between the moving target and the radar. Therefore, the signals from the comparators 31 and 38, which increase or decrease the range in the range counter 25, are produced at exactly the rate required to track the target. Further, the range counter 25 must move the tracking gate by an amount equal to or slightly greater than the radial distance change between the radar and the target which produced the doppler cycle otherwise the video pulse from the video amplifier 16 will move in range at a faster rate than the tracking gates and tracking will be lost. The amount, or step, that the tracking gates move for each doppler cyle, or each pulse applied to the range counter 25, must be equal to or greater than one half of the carrier wavelength.
The fact that the present apparatus always tracks on the leading edge of the reflected pulses allows rejection of multipath effects and enhances accuracy when tracking extended targets, because the apparatus is always tracking the nearest point. Because the apparatus does not require a sensitive servo loop it is capable of tracking targets that vary widely in range, velocity and acceleration and, further, the apparatus is relatively inexpensive and simple to manufacture. | A first variable tracking gate is generated which activates a sample and hold circuit connected to receive incoming signals from a doppler radar receiver and apply output signals therefrom to a threshold circuit which in turn supplies a signal to a range counter each time the signal from the sample and hold circuit exceeds a predetermined threshold, whereupon an output from the range counter decreases the range at which the tracking gate is generated. A second tracking gate, generated a short time after the beginning of the first tracking gate, activates a second sample and hold circuit connected to receive signals from the radar receiver and supplies signals through a second threshold circuit to the range counter to increase the range of the first gate when the signal from the second sample and hold exceeds a predetermined threshold and signals from the first sample and hold circuit are below the predetermined threshold. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates generally to the printing of webs, and more particularly to the printing of traveling webs. Still more particularly, the invention relates to an apparatus for printing a traveling web.
It is known to print traveling webs in printing machines, usually of the screen printing type. Especially if the web is a textile web, and if a screen printing machine is used, it is customary to apply the web onto a traveling printing blanket of the machine, which serves to support the web. Usually, the web is adhesively secured (by means of adhesive which allows it later to be stripped off) to the printing blanket, or else the printing blanket is provided with needle projections which penetrate into the web (this is usually done when the web is of a heavy quality, for instance a carpet). The purpose is to assure an absolute uniformity of the movements of the web and the printing blanket; in other words: no relative displacement of printing blanket and web is to be allowed to occur.
Theoretically, this approach works well. In actual fact, however, difficulties are frequently experienced, especially if the web is of a relatively heavy character, for instance carpeting or the like. Heavier textile webs, such as carpets, cannot be so produced that they are absolutely uniform in tension over their entire width. As a general rule, the edge portions of such a web are woven more loosely than the center portions, or sometimes the reverse might be true. In any case, it is well known that if a web which has this differential characteristic is advanced in the manner outlined above through a screen printing machine, bulges will frequently form in the web when it passes beneath the printing screens, with the result that the image or pattern that is being printed onto the web will become blurred and unsightly. The reason for this is that the web will be locally squeezed as it passes under the printing screen and an unsightly print will be obtained, or a local relative displacement will occur between portions of the web that are displaced by contact with the printing screen, and the printing screen and printing blanket.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to overcome these disadvantages of the prior art.
More particularly, it is an object of the present invention to provide an improved apparatus for printing a traveling web which is not possessed of the aforementioned disadvantages.
Another object of the invention is to provide such an improved apparatus in which tension differentials within the web to be printed are compensated, thus assuring that the print that is applied to the web is not blurred or otherwise of undesirable characteristics.
In keeping with the aforementioned objects, and with others which will become apparent hereafter, one feature of the invention resides in an apparatus for printing a traveling web which, briefly stated, comprises means for guiding a web onto a movable support, means for advancing the web and the support together in a common direction but at differential speeds, and means for printing onto the thus supported web.
The web is supplied onto the movable support, such as a printing blanket, in an already tensioned state so that its internal stresses or tensions are already equalized. This equalization is maintained due to the fact that the differential speeds of advancement of the web and the support, of which the latter travels at a slightly faster rate of speed than the web, maintains a tension upon the web which is uniform over the entire width of the web due to the frictional engagement of web and support, and the slight slippage resulting from the speed differential.
A further important concept of the invention provides for the printing to take place wholly or partially in relative movement with reference to the direction of advancement of the web itself. In other words, it is desired to obtain a certain amount of slip between the surface of the web onto which the print is applied, and the printing screen which effects the printing. The printing screen may be operated at a speed which is fast or slow with respect to the advancement of the web, since in either case a further tension will be exerted upon the web and a further equalization of tensions in the web will be obtained. The desired slip must, of course, be small and can be on the order of approximately 1 or 2 percent, so that it will not be sufficient to cause a noticeable distortion in the applied print. On the other hand, the ability of providing such slip makes it possible, assuming that several screen printing units are provided which all print upon the web one behind the other, and assuming that they can be independently controlled as to their speed of operation, to obtain shifts in the pattern of the print that is being applied to the web.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a diagrammatic side view illustrating one embodiment of an apparatus according to the invention;
FIG. 1a is a more structural overall side view showing the machine of FIG. 1;
FIG. 2 is a diagrammatic sectional view illustrating details of a drive arrangement for driving the printing screens of the screen printing units of the machine in FIG. 1;
FIG. 3 is a partly sectioned detail view illustrating an embodiment of a drive for the feeding roller which feeds the web in the machine of FIG. 1;
FIG. 4 is a fragmentary detail view illustrating an embodiment of a main machine drive for the machine in FIG. 1;
FIG. 5 is a view analogous to FIG. 1, but illustrating a somewhat different embodiment of the machine;
FIG. 6 is a fragmentary enlarged axially sectioned view in a section taken on line VI--VI of FIG. 5, illustrating a slip coupling used in the embodiment of FIG. 5;
FIG. 7 is a view analogous to FIG. 6, but illustrating a somewhat different embodiment of the slip coupling;
FIG. 8 is a sectioned view showing the structural details of the arrangement that is diagrammatically shown in FIG. 3;
FIG. 9 is a diagrammatic detail view, on an enlarged scale, showing a detail of the feeding arrangement which feeds the web into the machine;
FIG. 10 is a side-elevational view of one of the printing units 6 of the apparatus;
FIG. 11 is an end-elevational view of the printing unit in FIG. 10;
FIG. 12 is a sectioned view showing on an enlarged scale the structural details of the diagrammatically illustrated arrangement in FIG. 2;
FIG. 13 is a fragmentary partly sectioned detail view illustrating an exemplary embodiment relating to the arrangement of the slip coupling with reference to the feeding roller of the machine;
FIGS. 14 and 15 are somewhat diagrammatic detail views illustrating details of the web feeding arrangement of the machine; and
FIG. 16 is analogous to FIG. 1, but illustrates a somewhat different embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawing in detail, and firstly to FIGS. 1, 1a and also 5, it will be seen that a web 1 which is to be printed, for example a strip of carpet which may have a width on the order of 15 feet, passes between the nip of a pair of cooperating nip rollers 2 in the direction indicated by the arrow, and then forms a loop 10 which is tensioned by a tensioning device 3. From the tensioning device 3 the carpet 1 then travels to the feeding device 4 which feeds it by cooperation of its feed roller 40 with the guide rollers 42 and 43 which constitutes guide means for the web onto the upwardly directed side of a traveling printing blanket 5 which travels towards the right in FIG. 1 about the rollers 50, 51, 52 and 53. On the printing blanket 5 the carpet 1 travels beneath a plurality of printing units 6 which are diagrammatically illustrated in FIG. 1, and more structurally in FIG. 1a, and which for purposes of this specification will be discussed as being rotary-screen printing units each having a squeegee roller located within the respective tubular printing screen. However, it should be understood that non-tubular printing screens could also be used, and in fact the application might also be employed with printing units which do not operate on the screen printing principle.
The roller 51 is a tension roller with is spring biased towards the right in FIG. 1, as indicated by its associated arrow, and which serves to maintain the printing blanket 5 in tensioned condition. The tension of the printing blanket 5 can be further regulated by the roller 56 which is not spring biased but is so mounted that it can be moved with reference to the printing blanket 5, in a sense causing the latter to become more or less tensioned; i.e., the roller 56 in FIG. 1 is mounted so that it can be moved up or down to thereby tension or relax the printing blanket 5. The rollers 52 and 53 serve as reserving rollers for the printing blanket 5, and the drive of the latter could be obtained by making one or the other of these two rollers a driven roller. In the illustrated embodiment, however, it is the roller 50 which is driven and thereby advances the printing blanket 5. FIG. 4 shows that the drive can be imparted to the roller 50 via the main shaft 8, 8a which, in turn, is driven from an electric motor 55 that is controlled by a motor control unit ST, via an interposed continuously variable transmission 54. Reference numeral 80 in FIG. 4 identifies an output drive by means of which motion is transmitted also from the shaft 8 to the drives for the printing screens of the units 6.
To carry out the method of the present invention, the web 1--e.g., a strip of carpet--travels between the nip of the nip rollers 2 which tightly engage it during such travel, and forms downstream of these nip rollers 2 the loop 10. In order to tension the carpet 1, the tensioning device 3 is provided having a roller 30 which engages in the loop and which is mounted for rotation about a shaft 31 on the piston rod 32 of a fluid pressure operated cylinder 33 that is suitably mounted on the frame of the machine. When fluid is admitted into the cylinder 33, the piston thereof will move downwardly and urge the roller 30 against the carpet 1 within the loop 10. Since from the loop 10 the carpet 1 passes around a feed roller 40 of the feeding device 4, which it surrounds over a substantial portion of its periphery due to the location of the guide rollers 42, 43 under which it must pass, the operation of the tensioning device 3 tensions the carpet 1 intermediate the nip of the rollers 2 and the device 4. A photoelectric arrangement 7 may be provided to control the length of the loop 10, and may be connected as illustrated via an amplifier V with a motor control unit M of a drive for rollers 2 to regulate the speed of the carpet 1 and to thereby maintain the loop 10 of substantially uniform size, in that deviations from this size are detected by the photoelectric detector 7 and cause variations in the feeding speed until the loop 10 is restored to its original intended size.
The feeding device 4 has the aforementioned feeding roller 40 which preferably is provided on its circumference with a high-friction layer 41, for instance a layer of natural or synthetic rubber which prevents relative slippage between the roller 40 and the carpet 1. The rollers 42, 43 are mounted so as to extend in axial parallelism with the axis of the roller 40, and by being so located that the carpet 1 must loop around a large portion of the periphery of the roller 40 they serve to further prevent slippage between the latter and the carpet 1.
From the roller 43, the carpet 1 moves onto the upper surface of the upper run of the printing blanket 5. According to the present invention the speed at which the carpet 1 and the printing blanket 5 advance while they are in contact is to be differential, and in fact the speed of advancement of the printing blanket 5 is to be somewhat greater than part of the carpet 1. This speed differential is obtained by driving the roller 50 and the roller 40 at different angular speeds, in that the roller 40 rotates slightly more slowly than the roller 50. The speed differential can be quite small and can be readily determined empirically by those conversant with this art. The only requirement is that a slight tension develop in the carpet 1 due to the frictional engagement between the same and the printing blanket 5, and the tendency of the printing blanket 5 to overrun the carpet 1. The thus developing tension is sufficient to maintain the equalization of the differential tensions originally existing in the carpet 1 over the width thereof, which was obtained by the device 3, or even to aid in obtaining this equilization.
As the carpet 1 travels with the printing blanket 5 in clockwise direction in FIGS. 1, 1a and 5, it passes beneath the printing units 6 which, as pointed out earlier, are here illustrated as having tubular printing screens, although other printing devices, including non-tubular printing screens, could also be employed. Similarly, the number of printing units 6 could differ from the number that has been illustrated for purposes of example.
The shaft 8, 8a shown for instance in FIGS. 1 and 4, is intended to symbolically represent the main drive of the machine. It is provided with the aforementioned output drive 80 which transmits motion to angle drives 81 of the respective printing units 6. Two of these units with their drives have been illustrated diagrammatically in FIG. 2, and it will be appreciated from a comparison with FIG. 1 that the angle drives of the several units are all, in turn, connected for joint operation by a shaft 82. Structural details of this arrangement are shown more clearly in FIG. 12. Reference to these Figures will show that the shaft 82, which can also extend to the drive for the roller 40, as will be discussed later, drives the angle drives 81 of the several printing units 6. Each of the angle drives has an input gear 81a and an output gear 81b. The shaft 83 of the output gear 81b carries a gear 84 and is connected via a further gear 85 with a planetary gear drive 9. The latter has a main shaft 90 which carries the gear 85 and is thereby connected with the angle drive 81, also drives a gear 91 which then rotates a planetary gear carrier 92. The latter engages with gear ring 93 which is mounted on the shaft 90 so as to freely turn about the same. The gear ring 93 meshes with an intermediate gear 94 which transmits motion to gears 95 and 96 which then drive the tubular printing screen 60 of the respective printing unit 6. They can also drive the squeegee roller 61 which is located in the interior of the tubular printing screen 60. For this purpose, the shaft 62 drives via the gears 95' and 96', and an intermediate gear 94, the squeegee roller 61 in rotation, and the arrangement obtains a uniform relative rotation of the printing screen 60 and the squeegee roller 61.
To operate the planetary gear drive 9 and make it effective when desired, a control motor 97 is provided which turns the gears 98 and 99 and thus rotates the shaft 92' of the planetary gear carrier 92 which loosely rotates about the shaft 92'. When the control motor 97 is not energized, there is a simple gear transmission via the angle drives 91 to the several printing screens 60 of the respective printing units 6. In other words, all of the printing screens 60 operate at one and the same circumferential speed. When the motor 97 is energized, the planetary gear drive 9 of the respective printing unit 6 is operated and, depending upon whether the motor 97 is used for speeding up or retarding the rotation of the respective printing screen 60, the circumferential speeds of the printing screens 60 of the several units 6 can be adjusted as desired with reference to one another. FIG. 2 shows clearly that the drive arrangement can be identical for all of the printing units 6, as suggested by the two printing units that are illustrated in that Figure.
The rotational speed of the rotor 40 can be similarly regulated, and the drive for it can also be of the same type as that employed for the printing units 6. This is illustrated in FIGS. 3 and 8, where another angle drive 81, also driven by the shaft 82, will be seen to act upon and turn the gears 184 and 185. The gear 185 has a shaft 190 which turns a gear 191 that drives the planetary gear carrier 192 of a planetary gear drive 19. The carrier 192 engages with gear ring 193 which, in turn, can act directly upon a gear 140 of the roller 40, to rotate the shaft 45 of the latter. A control 197 is provided for this drive also, and the output shaft thereof turns the gear 198 which meshes with a gear 199 that is mounted on the shaft 192' of the planetary gear carrier 192 and turns the latter via the branch shaft 192". When it is desired that there be a speed differential between the speed of advancement of the carpet 1 and that of the printing blanket 5, the motor 197 is operated to retard the speed of rotation of the roller 40 with respect to that of the roller 50.
It would, of course, also be possible to provide a completely separate drive for the roller 40, that is a drive which is not powered from the shaft 8. The principle of operation would, however, remain the same.
In any case, by resorting to the present invention and obtaining the desired differential speeds of advancement of the carpet 1 and the printing blanket 5, a largely or completely uniform tension over the entire width of the carpet 1 is obtained, even though the latter be of a width on the order of 15 feet and be in the process of being printed over this entire width. When the type of web that is to be printed does not present the particular problems with which the present invention is intended to cope, for example if it is a textile of light weight, then it will be appreciated that the construction herein disclosed makes it possible to have the web 1 and the printing blanket 5 advance at identical speeds, so that there is no relative displacement between them, and also to have no relative speed differential between the web 1 and the printing screens 60. If, however, a web is to be printed which presents the problems that have been outlined at the beginning of this specification, then the desired speed differentials can be readily obtained. Also, speed differentials between the web 1 and the printing screens 60 can be selected at will, in order to obtain different printed patterns, to shrink the patterns or expand them, and for similar purposes. It will be appreciated that the degree of precision of the pattern print will be much greater if there is no speed differential between the web 1 and the printing screens 60.
To provide for an automatic adjustment of the arrangement to the tension conditions and conditions of relative movement between carpet 1 and printing blanket 5 that exist at any given time, it is highly advantageous to provide, according to a further concept of the invention, an adjustable slip coupling 44 as part of the drive for the roller 40. FIG. 6 shows that the slip coupling 44 can be mounted on the shaft 45 of the roller 40, whereas FIG. 7 shows that it can also be mounted in the region of the shaft 82, and more particularly in the region of the angle drive 81 which is driven by the shaft 82 and, in turn, drives the roller 40.
The embodiment in FIG. 6 is the simpler of the two. It will be seen that in this embodiment, which is incorporated in the machine of FIG. 5, the slip coupling 44 has an annulus 46 of gear teeth, a portion 146 of which is clampingly retained in a groove formed between friction pads 47 which are respectively carried on the components 44a, 44b, of the slip coupling 44. The friction pads 47 are maintained in frictional engagement with the portion 146 by the dished or Belleville springs 48 of which any desired number can be provided, and which can be arranged in various ways, for instance only in the manner shown in FIG. 6 but also in that shown in FIG. 7. This means that the annulus 46 acts as a safety device to prevent overloading since, in the event of such overloading, slippage can occur between the portion 146 and the friction pads 47. The degree of pressure exerted by the springs 48 upon the friction pads 47 and therefore upon the portion 146, and thus the point at which relative slippage can occur, can be adjusted by turning of a tensioning ring 49 which is a part of component 44b. The pads 47 can be replaced readily with new ones.
The arrangement in FIG. 6 or alternately the one in FIG. 7, assures that the roller 40 can either be driven directly from the shaft 8 or from the shaft 82. If different carpets 1 having different characteristics or qualities are to be printed in the machine, the slip coupling 44 is readjusted by operation of the ring 49. Its presence assures that the operation of the feed for the carpet or web 1 is dependent upon the tension of the same, and that in dependence upon the particular characteristics of a web an automatic readjustment will take place which obtains a still further improved uniformity of the tension conditions within the web ahead of the printing units 6 than would be possible without the use of the slip coupling 44.
The slip coupling 44 could be replaced with a different type of device performing the same service, for example a hydraulic brake which would be throttled in case of excess pressure.
Returning to FIG. 8 for a further explanation, it will be seen that the control motor 197 acts upon a gear ring 297 via a coupling that is illustrated in section. The gearing ring 297 is of the adjustable type known in the art, and its presence means that the motor 197 which has to be controlled as to its rotation, for example by means of a resistor or the like, but that the control can be affected by adjusting the gear ring 297. The gears 198 and 199 were previously discussed with reference to FIG. 3, and the gear 199 transmits via the shaft 192" the planetary gear carrier 192 which turns about the gears 191 and 193. THe gear 193 is mounted on a sleeve and meshes with a gear 239 which, in turn, meshes with a gear ring 393 which is shown in FIG. 8, but not visible in FIG. 3. The gears 393' and 393" are turned by the gear ring 393, and in their turn rotate a gear 493 which turns the gear 140 (see also FIG. 3) that rotates the roller 40.
FIG. 9 shows diagrammatically how the drive can be transmitted to the roller 40 and how the various components can be located. It will be seen that the angle drive 81 can also be arranged in the manner from what has heretofore been discussed. The Figure also shows that an additional guide roller 152 for the printing blanket 5 may be provided, if desired.
FIGS. 10 and 11 are intended to show more clearly the arrangement of various of the components with reference to the printing screens 60, of which one is illustrated. Reference characters SP illustrate tension members which are located at opposite lateral sides of the printing screen 60 and connect the end mounts thereof in which the printing screen 60 is journalled for rotation. Reference character D identifies a support mounted on the frame G located beneath the printing blanket 5 and the carpet 1, as shown in FIG. 11, so as to provide support in the area where printing takes place.
The illustration in FIG. 12 has already been discussed, and it remains merely to point out that the control motor 97 here also is not of the type whose operation is controlled directly, but instead that the control motor 97 is coupled as illustrated with a variable gear ring 397. The gear 98 meshes with the gear 99 so that the shaft 90 is turned in rotation. The shaft portion 92' turns the planetary gear carrier 92 which rotates about the gear 91 and the teeth of the gear ring 93. The latter has gears 93' 93" and transmits motion to a gear ring 593 which has gears 593' and 593". Gear 593' transmits motion to gear 94 which transmits motion to gear 96 from where the printing screen 60 is driven in rotation. In this embodiment, no squeegee roller has been shown that is intended to be driven by this arrangement, and hence gear 95 is not necessary and has not been illustrated. Also, the gears 84 and 85 shown in FIG. 2 can be omitted in the embodiment of FIG. 12, and replaced with the coupling K, and the components 61, 62 and 95 can also be omitted.
FIG. 13 shows the arrangement of the slip coupling 44 which in this particular embodiment is arranged in the region of the roller 40, rather than in the region of the shaft 8.
FIGS. 14 and 15 show the feeding device 4 to illustrate that a belt or chain drive, utilizing in this embodiment the chain 146 (compare also FIG. 5) which transmits motion from the roller 52 that is driven from the shaft 8, to the slip coupling 44. Reference numeral 246 identifies a device for tensioning the chain 146 to the desired extent. In this embodiment the direction of travel of the carpet is from right to left (see FIG. 14).
Finally, FIG. 16--which shows the same apparatus as FIG. 1, except that some of the elements of FIG. 1 have been omitted for simplicity--illustrates that the tubular screen printing units 6 can be replaced with others, such as the traveling-band screen printing units 160. These have three axially parallel rollers 161, 162 and 163, about which a flexible band screen 164 is trained which forms a continuous belt. As the double-headed arrows indicate, the units 160 can be raised and lowered. One of the rollers, e.g., the roller 161, is driven and drives the screen 164 by friction, or in another suitable way, e.g., via a sprocket or the like. The printing units 160 are already known per se.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the type described above.
While the invention has been illustrated and described as embodied in a printing apparatus for printing traveling webs, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that from the standpoint of prior art fairly constitute essential characteristics of the generic or specific aspects of this invention. | A web is guided onto a movable support, such as a printing blanket, and the web and the support are advanced together in a common direction, but at differential speeds so that the web will be subjected to tensioning. Onto the thus supported and tensioned web, a print is then applied. The invention discloses an apparatus for carrying out the above sequence. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to a hydraulic system for mud pulse generation.
One technique used to drill a wellbore involves rotational drilling in which a drill string is rotated to actuate a drill bit at the remote end of the drill string. The rotating bit cuts through subterranean formations opening a path for the drill pipe that follows. Another technique involves using a motor, as opposed to rotating the drill string, to actuate the drill bit. The motor responds to drilling fluid that is forced through a central passageway of the drill string to the motor. The drilling fluid exits the motor and returns to the surface via an annular space, or annulus, that is located between the drill string and the wellbore.
It is usually desirable to obtain information about one or more downhole conditions as drilling progresses. For example, it may be desirable to know the wellbore inclination angle, wellbore magnetic heading and/or the tool-face orientation of the bottom-hole assembly to ensure that drilling is progressing in the right direction. Other useful information includes radioactivity of the formation to discriminate between sands and shale, resistivity and porosity of the formation to determine if oil is present.
These downhole conditions are typically measured by sensors located as near as possible to the bit. A downhole measurement while drilling (MWD) mud pulser transmits these measurements to the surface of the well by modulating the already present stream of drilling fluid that circulates down the central passageway of the drill string and up through the annulus. Sensor measurements are typically encoded in the stream by selectively restricting the flow of drilling fluid. As a result of these restrictions, the encoded data takes on the form of pressure pulses. Sensors at the surface of the well decode these pressure pulses to recover the downhole information from the mud stream.
SUMMARY OF THE INVENTION
In general, in one aspect, the invention features a hydraulic system for supplying hydraulic fluid for operating a mud pulse generator. The hydraulic system includes an accumulator that has a reservoir and a pressure operated, one way inlet valve. The accumulator is arranged to maintain the fluid pressure in the reservoir, and the valve is arranged to allow hydraulic fluid to be added, under pressure, to the reservoir.
Implementations of the invention may include one or more of the following. The one way inlet valve may have a valve core. The hydraulic fluid reservoir may have a fluid pressure accumulator.
In general, in another aspect, the invention features a method for charging a hydraulic system for a mud pulse generator. The method includes supplying hydraulic fluid under pressure through a one way inlet valve to a reservoir of the system.
Implementations of the invention may include one or more of the following. The hydraulic system may be located in a pressure housing of a downhole tool. The method may include submerging the hydraulic system in a tank of hydraulic fluid, applying a vacuum to the fluid to remove air from the hydraulic system, releasing the vacuum and mounting the pressure housing over the hydraulic system while the system remains submerged. The method may include maintaining the hydraulic system in one discrete assembly that is part of a downhole tool that has at least one other discrete assembly. The hydraulic system is charged before the discrete assemblies are connected together.
In general, in another aspect, the invention features a downhole tool for use in a high pressure environment in a subterranean well. The tool includes an accumulator that has a reservoir for storing hydraulic fluid and an actuator that has a shaft with a passageway adapted to establish pressure communication between the reservoir and the high pressure environment.
Implementations of the invention may include one or more of the following. The high pressure environment may include the hydrostatic pressure of a drilling fluid. The downhole tool may include a housing encasing the accumulator and actuator. The tool may also have a gasket that is adapted to form a seal between the housing and the actuator. The communication established by the passageway may minimize a pressure difference across the seaal. The actuator may include a rotary actuator.
In general, in another aspect, the invention features a method for use with a downhole tool that includes an accumulator having a reservoir with hydraulic fluid and a piston having a position indicative of a pressure level of the hydraulic fluid. The method includes determining the position of the piston, and based on the position, determining the pressure level of the hydraulic fluid.
Implementations of the invention may include one or more of the following. The tool may include an actuator that has a shaft with a passageway that is adapted to establish communication between the reservoir and an area surrounding the tool. The step of determining the position of the piston may include from outside of the tool, inserting a rod into the passageway a distance to contact the piston and determining the position based on the distance.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic view of a drilling assembly.
FIG. 2 is a vertical cross-sectional view of a portion of the drilling assembly of FIG. 1.
FIGS. 3 and 3A are schematic views of a turbine assembly of the drilling assembly of FIG. 1.
FIG. 4 is an exploded perspective view of the turbine assembly of FIG. 3.
FIG. 5 is a vertical cross-sectional view of the actuator assembly of the drilling assembly of FIG. 1.
FIG. 6 is an exploded perspective view of the actuator assembly of FIG. 5.
FIG. 7 is a vertical schematic view of the mud valve assembly of FIG. 1.
FIG. 8 is an exploded perspective view of a portion of the mud valve assembly of FIG. 7.
FIG. 8A is and end view of the inner sleeve of FIG. 8.
FIG. 9 is a hydraulic diagram of the downhole tool assembly.
FIGS. 10 and 11 are perspective views of the connectors.
FIG. 12 is a cross-sectional view of the connectors when mated together.
FIG. 13 is an exploded perspective view of the circuit board assembly.
FIG. 14 is a schematic view illustrating connection of the actuator and turbine assemblies.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawing wherein like reference characters are used for like parts throughout the several views, a drill string 10 (see FIG. 1) is suspended in a wellbore 12 and supported at the surface 14 by a drilling rig 16. The drill string 10 includes a drill pipe 18 coupled to a downhole tool assembly 20. The downhole tool assembly 20 includes multiple (e.g., twenty) drill collars 22, a measurement-while-drilling (MWD) tool assembly 1, a mud motor 24, and a drill bit 26. The drill collars 22 are connected to the drill string 10 on the uphole end of the drill collars 22, and the uphole end of the MWD tool assembly 1 is connected to the downhole end of the drill collars 22. The uphole end of the mud motor 24 is connected to the downhole end of MWD tool assembly 1. The downhole end of the mud motor 24 is connected to drill bit 26.
The drill bit 26 is rotated by the mud motor 24 which responds to the flow of drilling fluid, or mud, which is pumped from a mud tank 28 through a central passageway of the drill pipe 18, drill collars 22, MWD tool assembly 1 and then to the mud motor 24. The pumped drilling fluid jets out of the drill bit 26 and flows back to the surface through an annular region, or annulus, between the drill string 10 and the wellbore 12. The drilling fluid carries debris away from the drill bit 26 as the drilling fluid flows back to the surface. Shakers and other filters remove the debris from the drilling fluid before the drilling fluid is recirculated downhole.
The drill collars 22 provide a means to set weight off on the drill bit 26, enabling the drill bit 26 to crush and cut the formations as the mud motor 24 rotates the drill bit 26. As drilling progresses, there is a need to monitor various downhole conditions. To accomplish this, the MWD tool assembly 1 measures and stores downhole parameters and formation characteristics for transmission to the surface using the circulating column of drilling fluid. The downhole information is transmitted to the surface via encoded pressure pulses in the circulating column of drilling fluid.
Referring to FIG. 2, from top to bottom, the components housed within the MWD tool assembly 1 include a bull plug 100, an upper rubber fin centralizer 300a, a survey measurement assembly 200, a lower rubber fin centralizer 300b, an interface assembly 400, a turbine assembly 500, an actuator assembly 600 and a valve assembly 700.
The bull plug 100 diverts the drilling fluid and protects the upper end of upper rubber fin centralizer 300a. The rubber fin centralizers 300a and 300b coaxially center the survey measurement assembly 200 and the interface assembly 400 that are housed within non-magnetic drill collar 2.
The survey measurement assembly 200 may include, for example, survey sensors, a microprocessor, microprocessor control program, and such additional supporting electrical circuitry (not shown) for producing electrical signals representative of downhole information that may be of interest. These electrical signals, via the interface assembly 400, control a spool valve 647 (see FIG. 5) within the actuator assembly 600. The spool valve 647 controls the flow of hydraulic fluid to a rotary actuator 657, which in turn, controls a valve sleeve 703. (See FIG. 7).
Referring to FIG. 7, the valve sleeve 703 may be shifted between positions of low resistance (referred to as the open position) and high resistance (referred to as the close position, though not totally restricting the flow) to the flow of the drilling fluid. Shifting the valve sleeve 703 from an open position to a closed position and then back to an open position generates a momentary pressure increase, or pressure pulse, which is detectable on the surface with a pressure sensor. Detected pressure pulses may be decoded in order to reconstruct the information of interest. Thus, in response to the electrical signals generate by the survey measurement assembly 200, pressure pulses are generated in the drilling fluid corresponding to the information of interest and the sequence of pressure pulses carries this information which is recoverable at the surface.
Referring back to FIG. 2, circuitry within the interface assembly 400 rectifies and regulates the three phase AC output of alternator 625. The regulated power is distributed to the survey measurement assembly 200 and the actuator assembly 600.
Drilling fluid flows through the drill string 10 and past the stabilizer 300a, the survey measurement assembly 200, the stabilizer 300b, the interface assembly 400, and then, into the inlet ports 510 (see FIG. 3) of the turbine assembly 500. Referring to FIG. 3, as the drilling fluid flows past the turbine rotors 538 the drilling fluid exerts a force on the turbine rotors 538 which causes a rotation of a drive shaft 539. The drive shaft 539, which is mechanically coupled to the actuator assembly 600, provides mechanical power to drive the alternator 625 and a hydraulic pump 634 (see FIG. 5). Electrical power provided by the alternator 625 powers the electrically systems, and hydraulic power provided by the hydraulic pump 634 powers the rotary actuator 657 which opens and closes the valve 700.
More detailed descriptions of components of the MWD assembly 1, such as a printed circuit board assembly 202, the turbine assembly 500, the actuator assembly 600, the valve assembly 700, and the connectors 550 and 608 are found below in the respective sections.
Turbine Assembly
Referring to FIGS. 3 and 4, the turbine assembly 500 is the system prime mover; that is, the turbine provides the rotary power to drive the alternator 625 and the hydraulic pump 634. The turbine assembly 500 is mechanically and electrically coupled and keyed to the actuator assembly 600.
The assembly of the turbine assembly 500 begins with the installation of a feed-through connector 518. Wires are soldered to both ends of feed-through conductors on the connector 518, the two O-rings 517 are installed in the O-ring grooves 518a on the body of connector 518, and then the connector 518 is installed in a weldment 512. In the course of installing the connector 518, the wires on the top side of connector 518 are fed from the lower end of the weldment 512 through a hole 512a in the center of weldment 512 up to and through the upper end of weldment 512. The connector 518 is seated in gland 512e, and the wires on the up-hole side are trimmed and soldered to connector 501. The O-ring 502 is installed on the outside of the connector 501, and the wires are folded and stuffed into the upper end of weldment 512 as the connector 501 is installed in the upper end of weldment 512.
The connector 501 is keyed to the upper end of weldment 512 by set screws 516. The connector 518 is a high pressure, high temperature connector designed to protect connector 501 and the balance of the electronics installed above connector 501. The connector 518 is held in place by the interference between the body of connector 518 and tapered ring 519. The tapered ring 519 is, in turn, held in place by accumulator housing 525.
The interface assembly 400 is connected to the top end of the weldment 512 via threaded nut 506. One of the two O-rings 511 is installed in O-ring gland 512c on the upper end of the weldment 512, and nut 506 slipped onto the upper end of the weldment 512. The two half-shells 504, which are installed in groove 512b and held together by O-ring 503, hold the nut 506 in place on the weldment 512. The second of the two O-rings 511 and O-ring 505 are installed in conjunction with the installation of the rubber fin centralizer 300b.
The drilling fluid is directed through the turbine assembly 500 via a diverter 510 which slides over the upper end of weldment 512. The diverter 510 is keyed in place with dowel pins 513 and held in place on top of the weldment 512 by a nut 508. The O-ring 507 is installed in an interior gland of nut 508, and the nut 508 slides over the upper end of weldment 512 and is threadedly attached to the weldment 512. The O-ring 507 keeps debris out of the threaded area below the O-ring 507. The drilling fluid may be extremely abrasive and diverter 510 is a disposable part that absorbs the wear caused by the incoming drilling fluid.
The turbine accumulator includes elements 521, 522, 523, 524 and 525. The turbine accumulator provides a means to maintain a net positive pressure, with respect to the hydrostatic pressure of the column of drilling fluid, in the interior cavities of the turbine. The snap ring 520, which is installed in an interior groove of accumulator housing 525, is a means to stop the upward displacement of piston 522. The two O-rings 524 are installed in the two O-ring grooves on the lower end of housing 525, and the accumulator housing 525 slides into the cavity within 512 from the lower end.
The wires on the lower side of feed-through connector 518 are fed down through the cavity within the weldment and into cross holes 512c as shown in FIG. 4. As housing 525 slides into place the wires running from connector 518 are worked into the grooves 525a running along the outside of 525. The relative alignment of the grooves 525a and the cross holes 512c is maintain by dowel pins 526 which engage the slots 525b on the accumulator and slots 512d on the weldment. After this assembly has been completed, the wires on the lower side of connector 518 run laterally down to the top of grooves 525a, along side the accumulator housing in grooves 525a and into the cross holes 512c. The accumulator housing 525 holds tapered ring 519 and connector 518 in place via the interference of the parts. The accumulator housing 525 is, in turn, held in place by the interference between housing 525 and the upper bearing housing 533.
The upper end of shaft 539 is secured by bearing 532 which is seated in upper bearing housing 533. The housing 533 surrounds the bearing 532, disc springs 529 (that go in on top of the bearing 532), the piston 528 and an O-ring 527. The O-ring 527 goes in the O-ring groove on piston 528 and slides into the opening 533b of housing 533. On each side of the housing 533, near the outer edge, are two O-ring glands 533a. An O-ring 530 fits in each of these glands 533a. The glands 533a are associated with the conduit 557 that extends through the turbine assembly 500 to provide the means to run wires from connector 518 to connector 550. On the underside of 533 is a gland for shaft seal 534. Seal 534 is a lip seal which may be encapsulated in a stainless steel housing. Seal 534 is held in place by snap ring 535. The seal 534 seals the passage between the housing 533 and the shaft 539.
Below the upper bearing housing 533 are two turbine stators 536 and two turbine rotors 538. The rotors 538 are keyed to shaft 539 via key 540. The bottom rotor slides over the upper end of shaft 539 and shoulders up on the raised area 539a on shaft 539. The turbine stack is assembled by sliding the lower rotor 538 onto the shaft 539 from the upper end of the shaft 539 and then sliding the lower stator 536 over the lower rotor 538 from the upper end of shaft 539. Next, the upper rotor 538 slides onto the shaft 539 from the upper end of shaft 539 and is axially fixed in position by a snap ring 537. The rotors are axially positioned on shaft 539 between the raised area on the area 539a on the shaft 539 and the snap ring 537 located in snap ring groove 539b. Then the upper stator 536 slides over the upper rotor 538 from the upper end of shaft 539.
Each rotor 538 has evenly spaced fins 538a that are circumferentially located on the body of the rotor 538. Each stator 536 of the turbine assembly has evenly space ports that are circumferentially arranged about the stator. The passages through the stator are ports that run axially along the body of the stator while the passages through the rotor fins are defined by "cupped" blades. In traditional turbine design, the fins on both the rotor and stator are "cupped," and more specifically, they are "cupped" in the opposite direction. The rotors and stators of the traditional design are manufactured in a casting process which is burdened by large financial investment in the castings. Unlike traditional designs, by making the ports through the stator straight while maintaining a "cupped" profile for the rotor blades, the rotor and stator can both manufacture in small volume at a significantly reduced cost.
Below the lower turbine stator is a seal plate 541. On the underside of the seal plate 541 is a gland for shaft seal 542. The seal 542 is a lip seal which may be encapsulated in a stainless steel housing. The seal 542 is held in place by snap ring 543. The seal 542 seals the passage between the seal plate 541 and the shaft 539. The O-ring 544 seal is one of several seals that is employed to seal the internal cavity of the turbine assembly 500.
The lower weldment 546 features a means to secure the lower end of shaft 539, porting through the weldment 546 for wireways, means to key the turbine assembly to the pulser collar 4, and means to couple, electrically and mechanically, the turbine assembly 500 and the actuator assembly 600. The porting through weldment 546 includes O-ring glands 546a and ports 546c which extend axially down to intersect a diagonally drilled hole 546d, shown in FIG. 3, which extends axially downwardly and radially inwardly to intersect drilled holes 546e. Drilled holes 546e extend from the intersection with 546d to the lower end of the weldment 546. The weldment 546 is made up of two pieces to form the diagonal hole through the part.
The turbine assembly components, upper weldment 512, bearing housing 533, two stators 536, seal plate 541 and lower weldment 546 are held together by the cap screws 549. An advantage of this segmented assembly is that the bolts hold the assembly together so the assembly can be removed as a unit. The drilled hole wireways through the components are aligned with respect to one another and wires are fished through the wireways. As the components are brought together the upper end of shaft 539 engages seal 534 and bearing 532. Seal plate 541 and lower weldment 546 slide over the lower end of shaft 539, and seal 542 and bearing 545 engage the shaft 539 just below the raised area 539a. The bolts 549 hold together the upper weldment 512, lower weldment 546 and all of the intervening components. The bolts 549 go through the lower weldment 546 and through the seal plate 541, the two stators 536 and the upper bearing housing 533, and the bolts 549 are threadedly anchored in the upper weldment 512.
The wires which are pulled through the wireway porting in the course of assembling the turbine assembly are cut to length and soldered to the terminals on the connector 550. The connector 550 is attached to the lower end of weldment 546 with bolts 551, and the excess wire is folded over into pockets 546f of the lower weldment 546 and a potting material is used to secure the wires in the pockets 546f.
Referring to FIG. 3A, the sleeve 552 provides the means to mechanically attach the turbine assembly 600 to the actuator assembly 500. O-ring 547 is installed and sleeve 552 is slipped over the lower end of the weldment 546. The sleeve 552 is held in place by balls 554. A passage 550j along the side of connector 550 and a passage 546g along the lower end of the weldment 546 provides the means to load the balls 554 in the cavity formed by inner ball race 546h and outer ball race 552a. To load the balls, the turbine assembly is turned upside down and tilted slightly. The balls are dropped through the passages 550j and 546g, and the balls fall through the passages 550j and 546g into the cavity formed by inner ball race 546h and outer ball race 552a. The balls are held in place by a keeper 555 which is inserted into the passages 550j and 546g. Keeper 555 is in turn held in place by a screw 556. O-ring 553 is installed in an interior gland on sleeve 552 and provides a means to seal the passage between the threaded end of the sleeve 552 and the upper, threaded end of pressure housing 664.
The turbine assembly 600 includes conduits through which electrical wires extend through the assembly 600. A conduit 557 extends from the upper end of weldment 512 down through the center of 512, along the outside of 525 in the cavity formed by groove 525a, through the diagonally drilled hole 512c, axially through each of the components 533, 536, and 541, through the diagonally drilled hole 546d, axially through the drilled hole 546e, and radially through port 546i. This conduit 557 provides the means to run electrical wires from connector 501 to connector 550.
The electrical wiring through the turbine assembly provides the means to power the electronics located above the turbine assembly 500 with the alternator 625 which is located below the turbine assembly 500 in the actuator assembly 600. The electrical wiring through the turbine assembly 500 also provides the means to control the power to the solenoids within the spool valve 647. The spool valve 647 in turn controls the position, either open or closed, of the mud valve.
The lower weldment 546 rests on an inner, annular shelf 4a inside the pulser collar 4 (see FIG. 2). To key the turbine assembly 500 inside the pulser collar 4, the dowel pins 548 of the lower weldment 546 are configured to align with mating ports 4c (see FIG. 15) that are formed in the shelf 4a.
Actuator Assembly
The actuator assembly 600 provides hydraulic power to operate the mud valve and also provides electrical power to the electronics. Actuator assembly 600 connects to the turbine assembly 500 which provides the rotary power to drive the alternator 625 and the hydraulic pump 634.
Referring to FIGS. 5 and 6, a sub-assembly of the assembly 600 includes components 602 through 619 that provide a means to seal the upper end of actuator assembly 600 within pressure housing 664. This sub-assembly also provides the means to electrically connect alternator 625 and solenoid valve 647 to connector 550 on the lower end of turbine 500 and to mechanically couple alternator 625 and hydraulic pump 634 to drive shaft 539 of turbine assembly 500.
The bearing 603 is installed in the top of connector 608 and held in place by a snap ring 602. An O-ring 609 and a dowel pin 610 are installed in the lower end of the connector 608 and the non-rotating portion of the face seal 612 is inserted in the lower end of the connector 608. The O-ring 609 seals the passage between the connector and the non-rotating portion of the face seal 612. The rotating portion of the face seal 612 slides over the upper end of shaft 615 and is held in place by set screws (not shown). The O-ring 613 within the face seal 612 seals the passage between the face seal 612 and the shaft 615. Lower bearing 617 slides over the lower end of shaft 615, and shaft 615 is held in place via the opposed bearing 603 by securing bracket 619 to connector 608 with cap screws 604. Cap screws 604 run through the O-rings 607 and are anchored in threaded holes 619a in bracket 619. O-rings 607 seal the passage between cap screws 604 and connector 609.
The coupling 601 provides the means to couple shaft 615 to turbine shaft 539. The coupling 601 is threadedly attached to the upper end of shaft 615. In the course of attaching the turbine assembly 500 to the actuator assembly 600, the splined (external spline) end of shaft 539 engages the splined (internal spline) end of coupling 601.
The coupling 623, keys 616 and 624, and set screws 622 provide the means to couple shaft 615 to alternator shaft 625a. Coupling 623 is installed on shaft 615 and bracket 619 is secured to alternator 625 with cap screws 621 and washers 620. Set screws 622 secure the coupling 623 to shaft 615 and alternator shaft 625a.
Bracket 628, keys 626 and 633, and coupling 631 provide the means to couple hydraulic pump 634 to the alternator 625. The coupling 631 is secured to the shaft 625b via set screws 632 installed in the upper end of coupling 631, and bracket 628 is attached to the lower end of alternator 625 by means of cap screws 629. Set screws 632 installed in the lower end of coupling 631 secure coupling 631 to the shaft of the hydraulic pump 634.
The bracket 639 provide the means to secure the hydraulic pump 634 to spool valve 647. The bracket 639 also houses a relief valve 641 and strainer 637. The O-ring 638 and strainer 637 are installed in port 639a and secured in place with snap ring 636. O-ring 640 is installed on the relief valve 641, and the relief valve 641 is installed in bracket 639 from the lower end of the bracket 639. The relief valve is held in place by washer 642 and snap ring 643. The port through which the relief is installed is sealed off by plug 645 and O-ring 644. Post 641a is sealed with an expanded plug 665. The bracket 628, pump 634, bracket 639 and spool valve 647 are held together by cap screws 630. O-rings 635 and 646 are installed along the high pressure conduits through bracket 639 and spool valve 647 to maintain the integrity of the fluid flow to the spool valve.
An accumulator 664 is formed from O-rings 648, piston 649, disc springs 650 and a bracket 652. The accumulator provides the means to store within the actuator assembly 600 a small reserve volume of fluid and to offset the hydrostatic pressure due to the column of fluid in the drill string 10. O-rings 648 are install on piston 649, and the disc springs 650 and piston 649 are inserted in bracket 652. Grooves 652a in the upper end of bracket 652 provide the means for hydraulic communications across the end of the bracket 652.
The rotary actuator 657 and bracket 652 are secured to spool valve 647 with cap screws 660. Plug 655 and O-rings 651, 653, 654 and 656 are installed in the course of attaching bracket 652 and rotary actuator 657 to spool valve 647. O-rings 651 and 656 seal the fluid paths between the spool valve 647 and rotary actuator 657. O-ring 653 seals the passage between bracket 652 and plug 655, and O-ring 654 seals the passage between rotary actuator 657 and plug 655.
O-rings 658 and 659 are installed on the lower end of rotary actuator 657, and lug 663 is threaded onto the lower end of rotary actuator 657. O-rings 658 and 659 seal the passage between the lug 663 and rotary actuator 657.
O-rings 614 and 662 are installed in conjunction with the installation of the pressure housing 664. The actuator assembly 600, less the pressure housing 664, is placed in a horizontal tank fill with hydraulic fluid. Via the coupling 601, the alternator 625 and hydraulic pump 634 are rotationally driven in order to functionally check the system and to chase the air out of the hydraulic system. After removing the air from the hydraulic lines in the assembly, the assembly is removed from the horizontal tank and lowered into a vertical tank filled with hydraulic fluid and the tank is sealed. A vacuum is pulled on the tank in an effort to remove any addition trapped air. A predetermined vacuum level (e.g., a 28 inch vacuum) is held on the tank for a predetermined duration (e.g., 15 to 20 minutes), and then the vacuum is released. With the actuator assembly remaining submerged in the vertical tank, the pressure housing 664 is slipped over the actuator assembly and threaded onto lug 663. The actuator assembly 600 is then removed from the vertical and the valve core 606 is installed.
The accumulator 664 is charged with hydraulic fluid in the final stages of preparing the tool for use. Externally, a hydraulic pump is attached to the connector 608 via a port 608a, and hydraulic fluid is pumped into the system, charging the system to a nominal pressure of, for example, 250 psi. In the process of charging the system, piston 649 is moved downwardly compressing springs 650. After charging the actuator assembly 600, the charging apparatus is removed, and valve core 606 checks the back flow of hydraulic fluid until plug 605 is installed in connector 608. The top of plug 605 is flush with the surface so that it does not interfere with the make up of the connectors 608 and 550.
A hole through the shaft 657a of rotary actuator 657 and through plug 655 provides 1) the means to check the charge on the accumulator and 2) the means to communicate the hydrostatic pressure due to the drilling fluid to the interior of bracket 652. A rod inserted through shaft 657 facilitates a measurement of the location of piston 649 with respect to an external reference such as, for example, the lower end of lug 663. With regard to the second function, hydraulic communication between the drilling fluid on the outside of the actuator assembly 600 and the hydraulic fluid on the inside of the actuator assembly 600 provides the means to limit the pressure across the rotary actuator shaft seal (not shown) and the O-ring seals 607, 609, 613, 614, 658, 659, 661 and 662 to a pressure which is no greater that the accumulator charge. That balance is established by movement of piston 649.
Four grooves on brackets 652 and 639 are bolt passageways. This grooved structure reduces the need for deep hole drilling, thus enhancing the manufacturing process.
The slots 647a and 639b form a flow path for the circulating hydraulics fluid and a wire conduit for the wires that connect the solenoids of valve 647 to the connector 608.
Wires extend from spool valve 647 to the connector 508 and extend from the alternator 625 to the connector 508. To take slack in the wires, the wire runs along side of the bracket 619 and is folded into the pocket 619b and held in place by O-rings 618. Similarly, wires that run along side of the bracket 628 are held in place by O-rings 627.
Mud Valve Assembly
Referring to FIGS. 7 and 8, the lower end of a lug 663 receives the outer sleeve 701 of a mud valve 700. The inner sleeve 703 is attached to an actuator coupling 702 with hex head bolts 705 and lock washers 704 which are secured in threaded holes 702b. The splined coupling 702 engages the splined end 657a of actuator shaft 657 and provides the means to roughly align the flow slots 703b of the inner sleeve with the flow slots 701a of the outer sleeve. Slots 703a (see FIG. 8A), in the upper end of inner sleeve 703 provide the means for a precise alignment of slots 703b of the inner sleeve with respect to the slot 701a of the outer sleeve. As a matter of practice, the adjustment of the inner sleeve 703 with respect to the outer sleeve 701 takes place after outer sleeve 701 has been made up to the actuator assembly 600 and the turbine assembly 500 and actuator assembly 600 have been coupled together and installed in the pulser collar 4. After this adjustment has been completed, then valve collar 5 is made up to pulser collar 4. The inner valve sleeve 703 and spacer sleeve 706 held inside 701 by nut 707. Spacer sleeve 706 maintains the axial alignment of inner sleeve slots 703b with respect to the outer sleeve slots 701a. The nut 707 also secures the pulser assembly within pulser collar 300. Set screws 708 are installed in threaded holes 707a and pulled down against the end 701b of outer sleeve 701. The set screws 708 prevent nut 707 from backing off while tool assembly 1 is in service.
FIG. 8 is a section view of the mud valve. The primary components of the mud valve assembly are outer sleeve 701, inner sleeve 703, and valve collar 5. Drilling fluid flow proceeds downstream from the turbine assembly 500 through the annular passage between the outer wall of the actuator assembly 600 and the inner wall of the pulser collar 4. With slots 701a and 703b aligned the drilling fluid is flows radially inwardly, as indicated by the arrow C in FIG. 7, into the central axial flow passage 709 and down through the internal passage within 5 to the mud motor and out the bit.
Mud flow through the turbine assembly 500 provides rotary power to drive the actuator assembly 600, and in turn, the actuator assembly 600 provide the means to rotate the shaft 657a of rotary actuator 657. Rotation of shaft 657a causes the inner sleeve 703 of valve assembly 700 to rotation the small openings 703c of inner sleeve into alignment with slots 701a of the outer sleeve. This valve position is referred to as the closed valve position. In the closed position, the flow area through the valve is decreased, and thus, the pressure drop across the valve is increased. The actuator assembly 600 also provides the means to rotate the inner sleeve back to the original position, which is referred to as the open valve position, where inner sleeve slots 701a are aligned with the outer sleeve slots 703b.
A microprocessor within instrument package 200 makes measurements of parameters of interest and encodes those measurements as a sequence of valve positions. The mud valve may be closed and subsequently open after, for example, 1 second to create a pressure pulse which is transmitted through the continuous column of drilling fluid within the drill string. The sequence of valve positions, and thus, the pressure pulses, is correlated to the encoded measurements. At the surface the pressure pulses may be detected and decoded to obtain the measured valves of the parameters of interest.
Hydraulic Circuit
Referring to FIG. 9, the hydraulics equipment incorporated into the actuator assembly 600 provides the means to operate mud valve 700. The prime mover PM, which in this case is the turbine assembly 500, drives hydraulic pump 634. Fluid leaving the pump 634 flows to the spool valve 647 or the relief valve 641. Spool valve 647 is a four-way, three position tandem valve. With neither solenoid actuated the spool is centered with P ported to T. With solenoid 647b actuated the spool is shifted to connect P to A and B to T. In this configuration, fluid flows from the hydraulic pump 634 through the spool valve 647 to the A port of the rotary actuator 657 and thus, shifts the position of rotary actuator 657. As the rotary actuator 657 reaches the rotational extreme, the fluid flow to A ceases, line pressure builds, the relief valve opens at a predetermined pressure (i.e., 600 psi), and fluid flows across relief valve 641. As the vanes within the rotary actuator 657 shift positions, fluid flows out of the B port to T and back to the inlet of the pump through strainer 637. With solenoid 647c actuated the spool is shifted to connect P to B and A to T. Fluid flows from hydraulic pump 634 to the B port of the rotary actuator 657 and shifts the rotary actuator 657 in the opposite direction. As the rotary actuator 657 reaches the rotational extreme the fluid flow to B ceases and fluid flows across relief valve 641. As fluid flows into port B, fluid flows out of port A to T and back to the inlet of hydraulic pump 634 through strainer 637. Accumulator 664 provides the means to maintain a small net pressure, with respect to hydrostatic pressure of the column of drilling fluid, on the actuator assembly 600. The pressure compensation afforded by the accumulator provides an assurance that the pressure across the O-ring seals 607, 609, 613, 614, 658, 659, 661 and 662 and the shaft seals (not shown) within rotary actuator 657 do not exceed the initial charge pressure of the accumulator. Hydraulic fluid stored within the accumulator 664 serves as a small reserve volume of fluid to compensate for small fluid losses across the seals, particularly the face seal 612.
Connector Assembly
Referring to FIGS. 10, 11 and 12, the connectors 550 and 608 are configured to align with each other along a common central axis in order to establish electrical continuity across the connectors and to mechanically interlock the connectors. The mechanical connection restricts rotation of the connectors 550 and 608 about the common central axis with respect to each other and keeps the connectors engaged to each other. The connectors 550 and 608 provide the means to electrically connect the turbine assembly 500 to the actuator assembly 600.
Connectors 500 and 608 each have a similar design, with the differences pointed out below. Connector 550 has an annular body 550a with a central passageway 550d through which the rotary drive of the alternator and hydraulic pump passes. The central passageway 500d is coaxial with the central axis of the body 550a.
The interlocking connection between the connectors is formed from mating surfaces of the connectors. The body 550a of connector 550 has a raised, annular ridge 550n that partially extends around the central passageway 550d at the end of the body 550a. The ridge 550n forms an interlocking "clam shell" connection with a corresponding ridge 608n of connector 608 when the two connectors are mated. The end of the connector 550 has a bullet nose 550c which surrounds the central passageway 550d of connector 550. The bullet nose 550c is configured to engage annular passage 608d of connector 608. In this manner, the two ridges interlock with each other to prevent the connectors from rotating, one with respect to the other. The bodies of the connectors are locked together so as to minimize the relative motion of the connectors. In turn this minimizes the static and vibrational loading at the pin and socket interconnects.
The ridge 608n has embedded electrical sockets 608g that are configured to mate with corresponding pins 550e that protrude from body 550a near the end of the connector 550. The pins 550e are parallel to the central axis of the body 550a and extend from a portion of the end that receives the ridge 608n.
The pins, 550e and 608e, and the sockets, 608g and 550g, provide the means to electrically connect wires 550i of the turbine assembly and wires 608i of the actuator assembly. To accomplish this, the connector 608 has internal conductive rods 608h that are embedded in the body 608a and extend longitudinally from end to end of the body 608a. The conductive rods 608h are eccentric to the central passageway 608d and are mechanically secured and electrically isolated from the body 608a by an outer, insulative glass seal 608f. The sockets 608g are mechanically supported by a nylon sleeve 608p. Small drilled holes in the opposite end of each of conductive rods 608h provide the means to mechanically and electrically secure wires 608i to conductive rods 608h. The wires 608i are soldered to conductive rods 608h via the drilled holes in the end of the rods.
Similar to connector 608, connector 550 has internal conductive rods 550h that are embedded in the body 550a and extend longitudinally from end to end of the body 550a. The conductive rods 550h are eccentric to the central passageway 550d and are mechanically secured and electrically isolated from the body 550a by an insulative glass seal 550f. Near the mating end of the body 550a, pins 550e are extensions of the conductive rods 550h and are adapted to mate with the sockets 608g. Near the other end of the body 550a, conductive rods 550h extend beyond the body 550a. Small drilled holes in the ends of conductive rods 550h provide the means to mechanically and electrically secure wires 550i to conductive rods 550h. The wires 550i are soldered to conductive rods 550h via the drilled in end of the rods.
The connector 550 also has sockets 550g that are configured to mate with corresponding pins 608e of the connector 608. The pin and socket features of the one connector parallel the pin and socket features of the other.
Among the other features of the connectors, the body 550a of the connector 550 has four holes 550m that permit the bolts to pass through the body 550a. The holes 550m are parallel and eccentric to the central passageway 550d of the body 550a. The holes 550m are aligned with corresponding threaded holes 546j of the lower weldment 546 (see FIG. 3). The body 550a also has a keyway 550j that is exposed on the outside of the body 550 and extends along the longitudinal length of the body 550. The keyway 550j, along with a corresponding keyway 546g in the lower end of weldment 546, forms a passageway for loading balls 554. Threaded hole 550k provides a means to secure the ball keeper 555 with the screw 556.
The body 608a of connector 608 has four holes 608j that permit bolts to pass through body 608a. The holes 608j are parallel and eccentric to the central passageway 608d of the body 608a. The holes 608j are aligned with corresponding threaded holes 619a in bracket 619 (see FIG. 9). The O-ring glands within holes 608j provide the means to seal the passage between the bolts and the connector body 608. The ports 608k and 608q are connected by a hole drilled through the body 608. Both ports are threaded to receive pipe fittings such as a pipe nipple or a pipe plug. Pipe plug 605 (see FIG. 6) is installed in the port 608k after the actuator assembly has been charged. Within the drilled hole connecting the two ports, 608k and 608q, is a gland 608r designed to seal the port by threadedly securing valve core 606 (see FIG. 6) in the port.
The valve core 606 and seat may be tested by threadedly attaching port 608q of connector 608 to a hydraulic test stand.
In some embodiments, the bodies 550a and 608a of the connectors are made of metal and in other embodiments, the bodies 550a and 608a are made of an insulative material, such as PEEK. In the embodiments where PEEK is used, the conductive rods passing through the body of the connector are sealed directly to the body of the connector. Thus, the need for the glass seals is eliminated.
Printed Circuit Board Assembly
Referring to FIG. 13, a printed circuit board mounting assembly 202 is adapted to mount a printed circuit board 218 on the upper surface of a section 214a of a chassis 204. The chassis 204 includes two sets of upstanding quarter circular sections 206 which define between them a generally flat region 214 for receiving the printed circuit board 218. A plurality of upstanding guides 210 extend from the four corners of the region 214 to guide the printed circuit board into position on the surface 214. In addition, a plurality of screw holes 208 are adapted to receive screws (not shown).
A pair of electrical insulators 220a and 220b sandwich printed circuit board 218. The lower insulator 220b is a continuous sheet of insulating material such as Teflon® with a plurality of apertures 222b alignable with apertures 216 in printed circuit board 218. Similarly, the insulator 220a includes apertures 222a which mate with the apertures 222b and 218 in the insulator 220b and the printed circuit board 218, respectively. Insulators 222a and 222b include an openings 224a and 224b to accommodate any electrical components which extend outwardly from the surface of the printed circuit board 218. A semicircular cover 226 includes a plurality of screw holes 230 which mate with the holes 208 in surface 214. In addition, an opening 228 is provided to permit electrical wires to feed between the elements 206 and onto the printed circuit board 216.
When the assembly 202 is made up, the elements 220a, 218, and 220b are sandwiched on top of the surface 214 held in alignment by the upstanding pins 210. The whole assembly is sandwiched onto the surface 214 by the cover 226 which is threadedly connected by screws (not shown) to the surface 214. In this way, the printed circuit board 218 is uniformly clamped around its peripheral edge to the chassis 204. This peripheral clamping of the printed circuit board 218 serves to shift the mechanical modes of vibration of the printed circuit board and the components attached to the board to a higher frequency, into a frequency range where the energy available to excite the resonant modes of the printed circuit board and components is substantially reduced. Thus, the clamping of the printed circuit board reduces the effect of mechanical vibration which otherwise causes damage to the printed circuit board, solder joints and electrical components attached to the printed circuit board. Clamping the printed circuit board 216 serve to increase the useful life of the printed circuit board 216 and the components mounted thereon.
MWD Tool Assembly
As stated above, the turbine assembly 500 and actuator assembly 600 are designed to couple together mechanically and electrically. Referring to FIG. 14 As turbine assembly 500 is coupled to actuator assembly 600 the splined end of shaft 539 first engages the matching splined coupling 601. Then, the connector 550 on the lower end of turbine assembly 500 engages the connector 608 on the upper end of actuator assembly 600. As connector sleeve 552 is threaded onto the pressure housing the two connectors, 550 and 608, are pulled together, and the pins 550e (608e) engage the sockets of 608g (550g). Continuing to thread connector sleeve 552 onto the pressure housing, the nose 550d of connector 550 engages the opening 608d of connector 608.
Referring to FIGS. 3 and 4, to charge the turbine assembly 500 with hydraulic fluid, the assembly 500 is placed in a vertical position and filled with hydraulic fluid via a port 514a of the upper weldment 512. As hydraulic fluid is introduced into the system, the fluid displaces air trapped inside the assembly 500. This displaced air exits the assembly 500 through another port 514a (not shown) in the upper weldment 512. Once the air is substantially displaced, as evidenced by a flow of hydraulic fluid, a valve core 514 (e.g., a Shrader valve core) is installed in each of the ports 514a of the upper weldment 512. A plug 515 is then installed in one of the ports 514a above the valve core 514, and the hydraulic charging tool is attached to the other port 514a to charge the accumulator in the assembly 500 to a predetermined pressure (e.g., 100 p.s.i.). The charging tool is then removed from the port 514a, and a plug 515 is then installed in this port 514a to seal the assembly 500.
The assembly including the interface assembly 400, turbine assembly 500, actuator assembly 600 and outer valve sleeve 701 is threadedly attached to the lower end of lug 663 and is installed in pulser collar 4. The entire assembly slides into pulser collar 4 and the dowel pins 548 of the turbine assembly 500 are made to engage the mating ports 4c that are formed in the shelf 4a. Besides holding the turbine assembly 500, the shelf 4a also prevents the bolts 549 of the assembly 500 from backing out. Per the alignment procedure discussed above, the inner valve 703 is inserted through the open end of outer valve sleeve 701 and the inner valve 703 is aligned with respect to the outer sleeve 701.
The valve collar 5 slides over the outer valve sleeve 701 on the lower end of the assembly, and the valve collar 5 is threadedly attached to the lower end of pulser collar 4. The inner valve sleeve 703, spacer sleeve 706 and the entire pulser assembly are secured by a nut 707, which is made up to the lower end of outer valve sleeve 701. The set screws 708 prevent nut 707 from backing off while the MWD tool assembly 1 is in service.
The assembly of the MWD tool assembly 1 is continued by attaching bull plug 110, rubber fin centralizer 300a, survey measurement assembly 200 and rubber fin centralizer 300b to the upper end of the pulser assembly (which is the upper end of the interface assembly 400). The cross over sub 3 and the non-magnetic drill collar 2 slide over the upper end of pulser assembly and are threadedly attached to the upper end of pulser collar 4.
Other embodiments are within the scope of the following claims. | A hydraulic system for supplying hydraulic fluid for operating a mud pulse generator includes an accumulator that has a reservoir. The accumulator is arranged to maintain the fluid pressure in the reservoir. The system also has a pressure operated, one way inlet valve that is arranged to allow hydraulic fluid to be added, under pressure, to the reservoir. The one way inlet valve also includes a valve core. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to knitting machines.
2. Description of the Prior Art
In circular knitting machines and other types of knitting machines, there is provided for each yarn feed, a lowering cam which acts on the butts of the needles to lower them in the active or stitch-forming stroke. There is associated with the lowering cam, which is sometimes termed the "drawdown" or "knocking-over" cam, a stop or counter-cam which faces the lowermost part of the lowering cam and which is spaced therefrom by a distance corresponding to the length of the butts in the direction of reciprocating movement of the needles.
With the increase of the speed of movement of the needles with respect to the cams, which occurs in modern machines for achieving higher production rates, serious problems arise owing to the high speed variations of the needles, operated by the above indicated cams, since the extension of the cam profiles is restricted owing to the available space in the machine and to the necessity of receiving selected needles which reach the cams at a relatively low level. Particular difficulties are encountered in the relatively sudden deceleration which the needles receive at the end of their lowering stroke imposed by the lowering cam when the needle butt contacts the stop cam. This deceleration must take place over a distance corresponding to 1 to 1.5 needle pitches, because otherwise the yarn would not be evenly drawn by the needles as too many needles and sinkers would be simultaneously in a retaining or gripping position.
In order to reduce the risk of damage to the needles due to the deceleration at the end of the needle lowering stroke, it has been proposed to provide the stop cam with an arcuate profile arranged to brake the needle gradually at the end of its lowering stroke. Hitherto, this profile of the stop cam has necessitated difficult and expensive machining of the two cams in order to obtain the required accuracy not only of the gap between the lower part of the lowering cam and the stop cam, but also between the last portion of the active profile of the lowering cam for the lowering of the needle butts and the initial portion of the stop cam profile (which must be parallel to the active profile of the lowering cam of the needle butts) and from which initial portion the aforesaid arcuate profile extends. On the other hand, it is necessary that the needle butt grazes the initial portion of the stop cam profile such that the arcuate profile of the stop cam effects deceleration of the needle according to a predetermined function or relationship.
SUMMARY OF THE INVENTION
According to the present invention, there is provided in a knitting machine, a lowering cam engageable with the butts of the needles to lower the needles along a predetermined lowering path, a stop cam engageable with the butts of the needles to effect progressive deceleration of the needles, said stop cam having means defining a first profile parallel with said lowering path, means defining a second profile corresponding to the maximum lowered position of the needles, and means defining a concave connecting profile between the first and second profiles, means for adjusting the position of one of said cams relative to the other of said cams in the direction of reciprocating movement of the needles, and means for adjusting the position of the other of said cams relative to the said one of said cams in a direction transverse to the first direction so as to ensure that the butt engages the stop cam tangentially to the connecting profile.
Further according to the invention there is provided in a knitting machine, a first cam engageable with the butts of the needles to move the needles longitudinally in a stitch-forming stroke, a stop cam engageable with the butts of the needles to decelerate smoothly the needles at the end of the movement imposed by the first cam, means for adjusting the position of the first cam relative to the stop cam in a first direction, and means for adjusting the position of the stop cam relative to the first cam in a second direction inclined to the first direction.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings, in which:
FIG. 1 is a front elevation of a cam support structure and associated cams, of a knitting machine in accordance with the invention;
FIG. 2 is a section taken on line II--II of FIG. 1;
FIG. 3 is a plan view looking along line III--III of FIG. 1; and
FIG. 4 is a developed schematic view showing the operation of the cams.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in the accompanying drawings, a cam support structure 1 has for each yarn feed and at a position at which the needles are to be lowered for the formation of loops, a sliding seat parallel to the direction of movement of the needles as indicated by the double arrow f 1 . The seat receives a slide 3 arranged to carry a lowering cam 5 and a stop cam 7. The slide 3 is adjustable in the seat by screw means or the like in order to adjust the stitch loop length, with this adjustment, there is obtained simultaneous movement of the cams 5 and 7 as a unit. The cam 5 is adjustably mounted on the slide 3 for movement relative to the slide 3 in the direction of arrow f 1 . Adjustment of the cam 5 on the slide 3 is obtained by means of a screw or pin 9 carried by the slide 3 and which forms an adjustable shoulder which is engaged by a clamping screw 10 of the cam 5. The screw 10 is accommodated in an aperture wider than the diameter of the screw 10 and passing through the slide 3. This arrangement permits the distance between the lower apex of the cam 5 and the cam 7 to be adjusted.
The cam 7 is provided with an initial profile 7A (see especially FIG. 4) and an arcuate connecting profile 7B between this initial profile 7A and a profile 7C arranged beneath the lower apex or maximum lowering zone 5A of the cam 5 and extending parallel thereto. The adjustment obtained by means of the screws 9 and 10 as described above allows the desired gap X to be provided between the profiles 5A and 7C. The arcuate connecting profile 7B serves to decelerate the butt T of a needle which is lowered along an active profile 5B of the cam 5, so as to obtain a desired rate of deceleration at the end of the needle lowering stroke. This action of the arcuate profile 7B however involves the necessity of adjusting to a very high degree of accuracy, the relative position of the cams 5 and 7 so that gap Y between the profiles 5B and 7A corresponds exactly to the dimensions of the butt T. The corner T of the butt T farthest from the profile 5B must graze the profile 7A so that the corner T O engages smoothly the profile 7B which decelerates the butt. If the corner T O moves along a path such that indicated by Z in FIG. 4 which is only slightly spaced from the profile 7A, there would be a sudden impact at the point Z O between the corner T.sub. O and the profile 7B and thus a sudden deceleration of the butt T and of the needle which may cause breakage or other damage to the needle. For this reason, the gap Y must be set with a very high degree of accuracy.
In order to avoid the above stated disadvantage, and in order to accurately adjust the gap Y with inexpensive and simple means, there is provided in the slide 3, a guide 12 perpendicular to the direction of the arrow f 1 and in which the cam 7 is slidable in the direction of the arrow f 3 . The cam 7 is locked in the guide 12 by means of a screw 14 similar to the screw 10 and cooperating with a screw or pin 16, with an arrangement similar to that already described for the adjustment of the cam 5.
With this arrangement, it is possible to obtain, in a simple manner, the adjustment of the position of the cam 7 with respect to the cam 5 in the direction of the arrow f 3 , without necessitating high machining costs and a high machining accuracy.
It should be noted that with the adjustment of the cam 7 with respect to the cam 5 in the direction of the arrow f 3 , the gap X is not altered between the two cams in correspondence of the lower apex of the cam 5. Therefore there is obtained with the adjustment of the cam 7, smooth deceleration of the butt by means of the arcuate profile 7B without any sudden impacts of the corner T O which at high speeds would be liable to cause breakage of the needle.
In an alternative arrangement (not shown), the cam 5 may be adjustable in the direction of the arrow f 3 and the cam 7 in the direction of the arrow f 1 . In other alternative arrangements the cams may be adjustable relative to each other in directions different to those indicated by the arrows f 1 and f 3 and inclined to each other, in such a manner as to obtain final adjustment which does not alter the previous adjustment or adjustments.
The invention is applicable to circular knitting machines for knitting hosiery, and to other types of knitting machines. | A knitting machine has a lowering cam which acts on the butts of the needles to lower the needles in an active stroke. A stop cam associated with the lowering cam acts on the butts to decelerate the needles at the end of the stroke. The relative positions of the lowering cam and the stop cam can be adjusted in two mutually transverse directions to ensure smooth engagement of the butts with the stop cam. | 3 |
This is a division of application Ser. No. 08/405,022, filed Mar. 16, 1995, now U.S. Pat. No. 5,603,968.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus for manufacturing a steering wheel pad and a method for manufacturing therefor.
2. Description of Related Art
Steering wheels with pads for accommodating air bags are widely used. Such pads are injection molded, using a resin material, into a configuration enabling the accommodation of air bags therein.
More particularly, as shown in FIG. 10, a known steering wheel pad body 32 includes a pocket 35a for securing a metal fitting 42 of an air bag device generally indicated at 43. The pocket 35a is defined between a first upper projection 34 and a hook-shaped second lower projection 35 both extending inwardly from the inner wall of the pad body 32.
A conventional mold 36, described with reference to FIGS. 8 and 9, is utilized to manufacture the conventional steering wheel pad 31 having two projections 34 and 35, which differ from each other in shape. The mold 36 comprises a fixed mold half 37, a movable mold half 38 which moves relative to mold half 37, and a pushing core 39 extensible along a moving path of mold half 38. The core 39 has a first protrusion 39a, a second protrusion 39b, and a depression "D" between the two protrusions 39a, 39b to form the two projections 34, 35 and the pocket 35a on the pad body 32.
For manufacturing the pad 31, a cavity 40 is first defined by moving the movable mold half 38, with the core 39 disposed therein, to a position close to the fixed mold half 37. Molten resin is then injected into the cavity 40 to thereby form the pad 31. Afterwards, the mold half 38 and the core 39 are separated from the mold 37. Subsequently, the pad 31 is separated from the mold half 37.
As shown in FIG. 9, the core 39 is separated from the mold half 38 to push the pad 31 out from the mold half 38. A lateral force is then applied to a bottom portion 33 of the body 32 by an operator's hand 41. This lateral force resiliently bends the bottom portion 33 to separate the second and first projections 35, 34 from the associated protrusions 39b, 39a, respectively, and thus permits the pad 31 to be separated from the core 39.
However, the above-described operation requires the operator to repeatedly apply force to bend the pad body 32 when removing the pad 31 from the core 39. This makes the manufacturing operation tiresome for the operator.
SUMMARY OF THE INVENTION
The objective of the present invention is to provide a steering wheel pad manufacturing apparatus and a simplified method for manufacturing a steering wheel pad, compared to those of the prior art, as discussed above.
To achieve the above objective, an apparatus for manufacturing a steering wheel pad is provided. The pad is formed by resin injection molding so as to have a cover and a pocket portion defined between a first projection and a second hook-shaped projection. The pocket portion holds an arm of an air bag device accommodated in the pad.
The apparatus has a first and second mold portions, such as a fixed mold half and a movable mold half which opposes the fixed mold half. The movable mold half is adapted to move along a predetermined path to selectively contact and separate from the fixed mold half. The apparatus further has a plurality of core members which are movable between retracted and extended positions with respect to one of the movable and fixed mold halves. The core members define a molding cavity along with the movable and fixed molds halves, when the core members are in their retracted position.
In particular, the core members include a first core member, for forming the first projection of the pad, which is movable along a predetermined moving path. At least one second core member and at least one third core member are also provided, the latter for forming the second projection of the pad.
According to another aspect of the present invention a method for manufacturing a steering wheel pad is proposed. The pad is formed by injecting a resin into a cavity to form a cover and a pocket between a first projection and a second hook-shaped projection for holding an arm of an air bag device accommodated in the pad. Then, by selectively extending and retracting the core members, the steering wheel pad can be separated from the mold apparatus without requiring an operator to exert manual force therefor.
First, the pad is formed by injecting a molten resin into a cavity defined by a fixed mold half and an opposed movable mold half. One of the mold halves includes the first, second and third core members, each being movable between a retracted position and an extended position with respect to one of the mold halves. Each of the core members is held in its retracted position at this stage.
Second, the movable mold half is moved along a predetermined moving path to separate it from the fixed mold half while the core members are maintained in their retracted position. The pad is held on the core members and the movable mold half;
Third, the core members are selectively extended and retracted so that pad becomes disengaged from the mold half and released. To accomplish this, each of the first and second core members are moved along the predetermined path, to an extended position and then the third core members are moved in a direction obliquely to and intersecting the predetermined path, whereby the pad is separated from the mold and the second projection is separated from the third core member(s);
Fourth, the second and third core members are retracted, during which time the second core members are moved in a direction along the moving path of the moveable mold half, and the first projection of the pad is separated from the second core member; and
Finally, the first core member is retracted so that the pad is separated from the first core member.
Other objects, features, and characteristics of the present invention, as well as methods of operation and function of the related elements of structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings, in which:
FIG. 1 (a) is a cross-sectional view taken along the line I--I of FIG. 7 showing a first step according to the present invention, in which a cavity of a mold is filled with molten resin;
FIG. 1 (b) is a cross-sectional view showing the movable mold half separated from the fixed mold half;
FIG. 2 is a partial cross-sectional view showing the second step in which a second projection of the steering wheel pad is separated from an inclined core member;
FIG. 3 is a partial cross-sectional view showing a third step in which a first projection of the steering wheel pad is separated from a first core member;
FIG. 4 is a partial cross-section view showing a second pushing core member moved upward from the position shown in FIG. 3;
FIG. 5 is a partial cross-sectional view illustrating a fourth step in which a pad is separated from the second core member;
FIG. 6 is a partial cross-sectional view showing a steering wheel with an air bag device therein;
FIG. 7 is a partial plan view showing a movable half mold, two core members, and an inclined core member;
FIG. 8 is a partial cross-sectional view illustrating a cavity of a conventional mold filled with molten resin;
FIG. 9 is a partial cross-sectional view showing a pad separated from the conventional core member of FIG. 8; and
FIG. 10 is an enlarged partial cross-sectional view of a conventional metal fitting for mounting an air bag.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
An embodiment according to the present invention will now be described with reference to the drawings.
FIG. 6 illustrates a portion of a steering wheel 2 with an air bag device 30 accommodated therein. The steering wheel 2 has a pad 3. The pad 3 includes a central cover 4 having an open bottom. The cover 4 has side walls provided with holding portions 5 integrally formed on the inner side thereof. The holding portions 5 serve to hold the air bag device 30 in place and are thicker than cover 4.
Each holding portion 5 includes a first upper projection 6 and a second hook-shaped lower projection 7, both extending inwardly. A pocket 29 is defined between the two projections 6, 7. Further, projections 6, 7 are generally perpendicular to a predetermined path of a movable mold 15 (seen in FIGS. 1(a) and 1(b).
The pad 3 is preferably made from an elastomer, such as a high polymer having rubber-like elasticity under normal temperatures. SEBS (styrene-ethylene-butadiene-styrene copolymer), for example can be used as the elastomer. Accordingly, pad 3 easily deforms under the application small stresses and returns quickly to its original configuration when the stress is removed.
The air bag device 30 comprises a main air-bag body 1 and an inflator 11 which supplies inflating gas to the air bag body 1. The air bag body 1 and the inflator 11 are attached to the holding portion 5 via, for example, a bag holder 8, a retainer 9, rivets 10, and nuts 12. More particularly, the top end of the bag holder 8 is engagingly inserted into a pocket 29. The bottom end of the bag holder 8, an open end 1a of the air bag body 1, and the retainer 9 are all held on a flange 11a of the inflator 11. Legs 9a project downward through the open end 1a of the air bag body. The legs 9a, the bag holder 8, and the flange 11a are each fastened by nuts 12. The retainer 9, open end 1a, and bag holder 8 are also secured in sandwiched manner by rivets 10.
To manufacture the above-described pad 3, the molding apparatus 13 shown in FIGS. 1(a), 1(b) and 7 is utilized. The mold apparatus 13 comprises a fixed mold half 14, a movable mold half 15, a first core member 16, four second core members 17, and four inclining core members 18.
The movable mold half 15 is typically moved vertically by a conventional drive mechanism (not shown) connected to the mold half 15. In this instance, the movable mold half 15 approaches the fixed mold half 14 when moving upward, and is separated there from when moving downward. On the upper section of the mold half 15, a number of recesses are provided for receiving various core members including a recess 19 for accommodating the first core member 16, four recesses 20 for accommodating second core members 17, and four recesses 21 for accommodating inclining core members 18.
The movable mold half 15 also includes rod passages 22, 23 that extend vertically through the mold half 15 and communicate with recesses 19, 20. The mold half 15 also includes four rod passages 24, each being inclined, with respect to the predetermined moving path of the mold half 15, at a designated angle θ. Each rod passage communicates with an associated recess portion 21.
The first core member 16 is fixed to a top of a push rod 25 which is slidably inserted into passage 22. The first core member 16 is provided with a protrusion 16a. Protrusion 16a extends outwardly and is generally perpendicular to the predetermined movement path of mold half 15. The core member 16 fits into the recess 19 when the core member 16 is in a lower, retracted position within mold half 15. Core member 16 is disposed above the recess 19 when the core member 16 is in a projected position outside the mold half 15 as in FIGS. 2-4.
The second core members 17 are fixed to the tops of push rods 26, respectively. Each of the rods 26 are slidably inserted into an associated rod passage 23. Each core member 17 fits into an associated recess 20 when the core member is in a retracted position within the mold half 15. The core members 17 will abut against the first core member 16 when the core member 17 are in a retracted position as in FIG. 1(a). The core members 17 project from the recess 20 when they are in a position outside the mold 15.
The inclined third core members 18 are each fixed to the top of one of the inclined push rods 27, respectively. Each push rod 27 is slidably inserted into an associated rod passage 24. Each third core member 18 has a second protrusion 18a. The protrusion 18a is generally perpendicular to the predetermined movement path of the mold half 15. Each third core member 18 fits in a respective recess 21 when the core member 18 is in a retracted position within the mold half 15. In their retracted positions, core members 18 abut against the bottom surface 16b of the first core member 16. Also, each core member 18 is disposed above the recess 21 when the core members 18 are in a projected position. Since each rod 27 slides upward at an inclined angle to lift core members 18 to the projected position, core members 18 also move inwardly in a direction oblique to the predetermined movement path of core member 16, as shown in FIG. 2.
The lower end portions of rods 25, 27 are connected to each other by a connecting member C. This connection allows movement of core members 16 and 18 to be synchronized while keeping core members 18 abutting against the bottom 16b of core member 16.
As shown in FIG. 1(a), a cavity 28 is defined by mold halves 14, 15 when the movable mold half 15 closes with the fixed mold half 14 and with all core members 16, 17, 18 being in their respective retracted positions.
The first projection 6 of pad 3 is formed between the first and second protrusions 16a, 18a, respectively. The second projection 7 of pad 3 is formed between second protrusion 18a and a step portion 15a (see FIG. 2) formed on the surface of movable mold half 15.
A method for manufacturing the pad 3, utilizing the above apparatus, will now be explained by the following sequence of steps.
In the first step as illustrated in FIGS. 1(a) and 1(b), core members 16, 17, 18 begin in their retracted positions and accommodated in their respective recesses 19, 20, 21. The movable mold half 15 is then moved upward to engage the fixed mold half 14. When mold half 15 comes into partial contact with mold half 14, a cavity 28 is defined between the mold halves 14, 15 and the core members 16, 17, 18. Molten resin (e.g., SEBS) is then injected into cavity 28 and cooled, thus forming a steering wheel pad 3 having the desired configuration.
The first projection 6 of pad 3 is formed between the first protrusion 16a of first core member 16 and protrusions 18a. The second projection 7 is formed between the protrusion 18a of each inclining core member 18 and mold 15.
In the second step, the movable mold half 15 and the core members 16, 17, 18 are first separated from the fixed mold half 14. This movement causes pad 3 to be separated from mold half 14 and moved downward, integral with mold half 15 and core members 16, 17, 18.
Then, with reference now to FIG. 2, core members 16, 17, 18 are simultaneously moved upward from the movable mold half 15. The pad 3 is thereby separated from mold half 15 and the core members 16, 17, 18 are extended from their respective recesses 19, 20, 21. The extended axis of the inclined rods 27 intersect the movement path of mold half 15. This enables core member 18 to move inwardly in a direction opposite to the direction of extension of second projection 7. The pad 3 is still held by core members 16, 17 and is, therefore, constrained from moving. Accordingly, the second protrusion 18a of core member 18 is separated from pocket 29 formed on the interior surface of pad 3.
In the third step, as shown in FIG. 3, the upward movement of the first and inclining core members 16, 18 is stopped. However, each of the second core 17 members continue moving upward. The pad 3, supported by core members 17, thus moves upwardly along with them.
Although the second projection 7 of the pad 3 was separated from the inclining core members 18, the first projection 6 remains engaged with protrusion 16a of the first core member 16 during the second step. However, during the third step, the holding portion 5 of the pad is gradually deflected due to its elasticity when the pad 3 is pushed upwardly by second core members 17. Hence, projection 6 is bent away from and separated from protrusion 16a. Afterwards, the holding portion 5 returns to its original configuration because of its own resiliency.
In the fourth step, the second core members 17, which support pad 3, are moved down from the position shown in FIG. 4. During the downward movement of core members 17, the simultaneous downward movement of the pad 3 is restricted when holding portion 5 contacts the protrusion 16a. This produces an upward force on that side of pad 3 counter to the force on the opposite side created by the downward movement of core members 17. These opposing forces separate the pad 3 from core members 17. After core member 17 is further retracted, the core members 16, 17, 18 move downward together and again fit into their associated recesses 19, 20, 21, as shown in FIG. 5.
Finally, an extracting mechanism (not shown) is separately provided to remove pad from the mold 13.
Although only one embodiment of the present invention has been described herein, it should be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention. Particularly, it should be understood that the present invention may be embodied in the modes given below.
(1) A different type of a mold half with a movable mold which moves horizontally may be employed. In this case, the pad may be dropped freely after being separated from the mold, thus making it possible to omit the extracting mechanism.
(2) In the third step of the above embodiment, only the second core members 17 are moved upward after the first and inclining core members 16, 18 are stopped. On the other hand, the second core members 17 may be stopped and the remaining core members 16, 18 may be moved downward. The significant feature is that pad 3 is supported by core members 17 while core member 16 moves away downwardly from pad 3 thereby establishing countering separating forces. This can be accomplished by suitable relative movement between the core members 16, 17.
(3) In the fourth step of the above embodiment, while the core members 17 are moving down, the downward movement of the 3 may be regulated by having pad 3 contact core member 18, or portions other than the protrusion 16a, on core member 16.
(4) In the fourth step, core members 16 and 18 could be moved upward instead of having core members 17 move downward.
(5) The core members 16, 17, 18 could be retracted and projected from the fixed mold half 14 instead of from the movable mold half 15.
While the invention has been described in connection with what is presently considered to be the most practical and preferable embodiments, it is to be understood that the invention is certainly not limited to these disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | A manufacturing method for an injection molded steering wheel pad having a cover and a pocket formed between a first projection and a second hook-shaped projection, that together hold an arm of an air bag device. The method includes use of fixed and movable mold members opposed to one another. The movable mold member moves along a predetermined moving path to selectively contact and separate from the fixed mold member. Core members are provided in one of the mold members for forming the first and second projections in the pad. To permit the removal of the molded pad core members are movable between retracted and extended positions with respect to one of the movable and fixed mold members so that the formed pad projections can be separated from the mold by varying movements of the core members, relative to each other and the mold in which they operate. | 8 |
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