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OBJECT OF THE INVENTION
[0001] The present invention relates to a mass, specially designed for the manufacture of high-capacity of radio-protection products, such as mass material, bricks, brick strips and/or special shapes.
[0002] The object of the invention is to achieve a mass with high homogeneity, with an optimum barrier effect against diverse kinds of radiation and diverse energy, allowing a marked reduction of the thickness of shielding barriers against standard materials to achieve the same barrier effect to said radiations.
[0003] Another object of the invention in one of its claims is to cause and/or accentuate the effect of neutron absorption and simultaneously the “capture” effect in their various energies by this material, and to eliminate or significantly reduce the effect of neutron scattering in enclosed facilities (scatter), which in the case of the bunkers for cancer treatment, it would mean that the patient would only receive the neutrons received directly from the main beam directly, eliminating those received by scatter effect. The electronics and room control systems are also benefited by this fact, as well as a significant reduction in the shielding of the bunker door, among other beneficial aspects.
[0004] The invention is applicable to any system of radiological protection, such as containers and/or mobile barriers of radioactive facilities, radiotherapy bunkers, or any facility where the existence of radioactive particles is expected, and where structural capacity is not required.
BACKGROUND OF THE INVENTION
[0005] Concrete with capacity of radio-protection have, in addition to the usual cement components, water and chemical additives which vary according to the characteristics intended for them, such as resistance, setting time, protection against freezing, assurance of the absence of cracking, marine environment, etc., and an aggregate that distinguishes them from conventional concrete.
[0006] The problem posed by this type of concrete is that in order to provide good radio-protection properties, it is necessary to have a considerable wall thickness, with the consequent and negative impact on weight, space, and cost, since the hydrogen content in the same is usually low.
[0007] Trying to avoid this problem, the Invention Patent with Application Number P 200900481 and publication number ES 2 344 290 is known, which describes a mass for the manufacture of products with high capacity of neutron radio-protection, mass that the same as any conventional concrete, is structured based on cement, aggregates, water and chemical additives that change the characteristics of the concrete, with the particularity that said mass uses as aggregate Colemanite with a very continuous grain size to achieve a perfect homogeneity in mass, determinant of a barrier effect against neutron radiation, which allows to significantly reduce the wall thickness without diminishing the barrier effect.
[0008] More specifically, said Patent envisaged the use of Portland cement, water, Colemanite and additives.
[0009] The patents of invention P200703404 and P200601392 provide similar effects for other particles and energies, and using another type of aggregates for X-rays and high energy Photons, respectively.
[0010] It would undoubtedly be desirable to continue to improve these results.
DESCRIPTION OF THE INVENTION
[0011] The material for absorption and attenuation of radiations proposed by the invention constitutes a new step forward in this technological field, with clearly improved results against the Patents of Invention mentioned above.
[0012] For this, more specifically, and in accordance with one of the features of the invention, the classic Portland cement, or in its case the Alumina cement used up to now, is replaced by an asphalt binder consisting of a mixture of hydrocarbons such as asphaltene, paraffin, olefins, naphthenic, aromatic, etc.
[0013] Polymers can be added to these asphalt binders, when it is desired to increase the working range of the product in temperature terms, so it is higher, thereby losing the consistency.
[0014] Asphaltic materials are characterized, inter alia, in that their hydrogen and carbon content is very high, and this is a very convenient situation for the construction of neutron shields.
[0015] As a means for neutron capture and absorption, the use of Colemanite (Ca 2 B 6 O 11 5H 2 O) as aggregate is shown, which is a borate calcium, which is very effective in neutron attenuation due to its boron and hydrogen content.
[0016] It has also been envisaged Colemanite to have a very continuous grain size, which on the other hand can be variable depending if the mass is intended to be poured, for the manufacture of bricks or for the manufacture of tiles.
[0017] Said particle size shall be comprised between 0 mm and 35 mm for obtaining poured mass, between 0 mm and 12 mm for obtaining bricks, and between 0 and 8 mm for the tiles, which features can vary both in positive sense and in negative sense in magnitudes of the order of 25%, depending on the dimensions of the final product.
[0018] From the suitable combination between aggregates and asphalt binder, is derived a significant increase in the number of molecules of hydrogen, very effective for neutron capture, primarily fast neutrons, absorbing them or thermalizing them, these thermal neutrons being the ones that are captured by the boron contained in the mixture.
[0019] For shielding and/or attenuation of X-rays, energies of up to about 500 KeV, energy range where the photoelectric effect predominates, the utilization of Barite (BaSO 4 ) as aggregate has been envisaged, since due to the atomic structure of the main component of the aggregate used, barium is more effective than other aggregate components with lower Z, in the shielding effect which is intended to be generated. Since the photoelectric absorption cross section is proportional in first approximation to Z 5 , i.e., heavily dependent on the Atomic Number of the absorbent material, 56 in the case of barium, main component of Barite, its utilization as basis of this product is optimal.
[0020] For high energy photons, above 500-600 KeV, which are subjected to the Compton effect, where the mass is a fundamental aspect for the attenuation and absorption of these particles, the use of minerals such as magnetite, hematite and even inclusion of steel shot has been envisaged, reaching densities of 4.3 Kg/dm 3 on a regular basis, (±15%), without the addition of shot, using the same hydrocarbon as a binder.
[0021] Finally, it has been verified experimentally that in some cases, for instance in mixtures corresponding to specific shields against neutrons, X-Rays under 500/700 KeV and Gamma-Rays above this intensity, and with regard to the main aggregates in the composition of the different corresponding materials, the presence of trapped air in the composition is possible depending of the type of asphaltic product and production method used, in which case, it has been envisaged adding to the mixture a “filler” of the same kind than the main aggregate of the composition, in an amount that may reach up to 10-15% of the total weight of the aggregate used.
[0022] In the hypothetical case of not having this “filler” available during the production phase, Portland cement could be added, below these limits, monitoring very closely the densities and the trapped air, as well as the eventual effects on the physical qualities of the produced sample.
EXAMPLES OF PREFERRED EMBODIMENT OF THE INVENTION
Example 1
[0023] In a practical embodiment of the product developed especially for specifically the neutron shielding, the following mixture has been prepared provided in % by volume and % by weight:
[0000]
Components
% Volume
% Weight
Hydrocarbons
14.5
8
Colemanite
85.5
92
[0024] These figures may vary ±15% according to the production processes to be used, fraction of aggregate to be used and objectives of priority weight such as radiation protection coefficients, mechanical strength of the mass, cracking, etc.
[0025] Mineral filler can be added up to a ratio of 1:1.5 of the hydrocarbon weight based on the changes of performance intended for the mass, such as fluidity, consistency, resistance, elasticity, etc.
[0026] Density is not a parameter pursued in a specific way, and will be the result of the optimization of the mixture; however it will be around 1.86 Kg/dm 3 .
Example 2
[0027] In a practical embodiment of the product developed especially for specifically the shielding against X-rays, the following mixture has been prepared provided in % by volume and % by weight.
[0000]
Components
% Volume
% Weight
Hydrocarbons
14.8
4.13
Barite
85.52
95.87
[0028] These figures may vary ±15% according to the production processes to be used, fraction of aggregate to be used and objectives of priority weight such as radiation protection coefficients, mechanical strength of the mass, cracking, etc.
[0029] Mineral filler can be added up to a ratio of 1:3 of the hydrocarbon weight to cause the physical changes mentioned above.
[0030] The densities obtained are around 3.68 Kg/dm 3 .
Example 3
[0031] In a practical embodiment of the product developed especially for specifically the high-energy photon shielding, the following mixture has been prepared provided in % by volume and % by weight.
[0000]
Components
% Volume
% Weight
Hydrocarbons
14.47
3.5
Magnetite, (*)
85.53
96.5
(*) Hematite, steel shot. In the case of the steel shot, since it has more density than magnetite and/or Hematite, the % by weight in the sample will be modified based on its participation in the same, maintaining the % by volume expressed.
[0032] These figures may vary ±15% according to the production processes to be used, fraction of aggregate to be used and objectives of priority weight such as radiation protection coefficients, mechanical strength of the mass, cracking, etc.
[0033] Mineral filler can be added up to a ratio of 1:4 of the hydrocarbon weight to cause the physical changes mentioned above.
[0034] The densities obtained are around 4.25 Kg/dm 3 . This density may be higher based on the incorporation of steel shot.
[0035] It should be noted finally that there is usually presence of neutrons at high energies, and that the high content of hydrogen of this product makes it particularly effective in this aspect of versatility in terms of radiation protection. | Products for obtaining masses for pouring, bricks, tiles and any other format are achieved, in which participate aggregates and asphaltic binders, as well as also additives for regulating the process. The invention achieves a remarkable increase in the capacity of neutrons, X-rays and/or photons radiation protection, and for this the use of asphaltic hydrocarbon as binder has been envisaged, while as aggregate is used Colemanite in absorption and attenuation of neutrons, Barite in the case of X-rays and Magnetite, Hematite and/or Steel shot in the case of photons. | 2 |
This invention relates to chewing gum products with improved stability toward L-appartic acid derived sweeteners. More particularly, this invention relates to a gum product of overall increased stability due to coextrusion or colayering the sweetener-containing composition(s).
In recent years, Aspartame has been employed as an artificial, low calorie sweetener in chewing gum compositions. However, chewing gum compositions employing Aspartame have characteristically exhibited impractical levels of instability. Instability may manifest itself in a number of different ways, such as by staling and by noticeable changes in texture, taste, color and the like. The instability of chewing gum compositions containing Aspartame is primarily attributable to the instability of Aspartame itself in heterogeneous environments which include, among other things, flavorings, especially aldehyde-based flavorings, and moisture components. Thus, one problem encountered by those skilled in the art of sugarless chewing gum compositions that employ Aspartame as a sweetener is the degradation of Aspartame due to the presence of aldehydes, which are used as flavorings, moisture components, and pH levels at which Aspartame exhibits instability, such as above about 4.5. This instability and other poblems associated with Aspartame are due to the wettability of the Aspartame crystal, as well as to its morphological configuration. More specifically, hydrolysis of Aspartame results in the formation of Schiff Bases. Also, Aspartame decomposes to phenylalanine and diketopiperazine (DKP) in the presence of aldehydes.
Numerous attempts in the art to stabilize Aspartame in chewing gum compositions have been disclosed. One attempt to stabilize Aspartame is by encapsulating it with a variety of formulated coatings For instance, U.S. Pat. No. 4,590,075 to Wei, et al. discloses a flavor and sweetener delivery system comprising sweetening agents, one of which is Aspartame, encapsulated in a matrix comprising at least one elastomer; at least one elastomer solvent; at least one wax system; an excipient selected from the group consisting of carbohydrates, polyhydric alcohols and mixtures thereof; and, optionally, spherical particles having microporous channels.
U.S. Pat. No. 4,556,565 to Arima, et al. discloses an encapsulated sweetener composition of L-aspartyl-L-phenylalanine methyl ester (APM) employed in a chewing gum base to form a chewing gum composition. The chewing gum composition also includes hydrogenated starch hydrolysate and/or hydrogenated maltose and a sugar alcohol wherein the chewing gum base excludes calcium carbonate and talc, and includes microcrystalline cellulose in lieu thereof.
U.S. Pat. No. 4,485,118 to Carroll, et al. discloses a gum composition and method for making same, which contains a sequentially releasable plural flavor system comprised of different flavors. One of the flavors is encapsulated within a water-insoluble coating. A separate liquid flavor is introduced individually and is available for immediate release.
U.S. Pat. No. 4,384,004 to Cea, et al. discloses the encapsulation of the artificial sweetener L-aspartyl-L-phenylalanine methyl ester (APM) within a coating material including cellulose ethers, cellulose esters, certain vinyl polymers, gelatin and zein, in a ratio of coating material to APM of 1:1 or less. The stabilized APM is particularly suited for incorporation into chewing gum formulations.
U.S. Pat. No. 4,139,639 to Bahoshy, et al. discloses the fixing or encapsulating of L-aspartyl-L-phenylalanine methyl ester (APM) in order to retard and/or prevent the conversion of APM to diketopiperazine (DKP), under certain moisture, temperature and pH conditions which can effect a chewing gum system.
U.S. Pat. Nos. 4,004,039, 3,956,507 and 3,928,633, each to Shoof, et al., disclose a sweetening composition wherein APM is discretely dispersed throughout a matrix created by melting a fuseable mass and subdividing it to encapsulate the APM therein. The sweetening composition of the disclosures are applicable to food mixes and patentees are not particularly concerned with chewing gum compositions.
U.S. Pat. No. 3,962,463 to Witzel discloses a chewing gum having an acceptable flavor but with a substantially reduced content of flavoring ingredients, obtained by impregnating or depositing solid flavor particles, such as microencapsulated flavor particles or flavors sorbed on an edible substrate, on the surface of the gum.
While the encapsulation or coating technique of stabilizing Aspartame has been successful to a limited degree, it does suffer a variety of disadvantages, since flavor aldehydes still penetrate the encapsulate and destabilize Aspartame. Aspartame is known to be rod-like, needle-like or dendritic in shape. As a result, it is very difficult to coat Aspartame using ordinary mixing or spray coating techniques. To be effective as protective barriers, coatings must be able to wet and adhere to the crystalline surface, including the needle-like tips and other shape variations of the Aspartame. Additionally, the coating must be capable of being applied in a film with a uniform thickness sufficient to provide a barrier against degradative factors such as moisture, pH changes, temperature changes and reactive chemicals. The coatings, in addition to being protective barriers, must be flexible enough to conform to the surface irregularities and geometrical configuration without cracking due to mechanical stresses which it is subjected to during incorporation of the sweetener into specific products.
It has been discovered that simple mixing of known materials, such as fats, with certain other core materials, such as Aspartame, does not provide adequate protection to keep the core material in a stabilized state. Fats have not been found to provide adequate coating materials, nor have such coating materials as starch and certain other materials such as waxes. Many of these materials require solvents and moisture for application, which have adverse effects on the stability of hydrophilic instable materials such as Aspartame. For example, simple mixing of Aspartame in liquid mixtures of traditional coating materials, e.g., fat and lecithin, has resulted in poor wetting, spotty coating and inadequate protection against moisture and chemicals. The result is degradation of the Aspartame upon exposure to these conditions. Changes in pH and temperature catalyze these degradative conditions.
Other shortcomings associated with encapsulates is that the gum compositions in which they are employed are initially organoleptically unsatisfying, since encapsulates shield the sweetener, i.e., Aspartame, from the consumer's tongue.
Other attempts at stabilizing Aspartame in chewing gum compositions are disclosed in U.S. Pat. No. 4,374,858 to Glass, et al. wherein the sweetness stability of an Aspartame sweetened chewing gum is enhanced by coating the Aspartame onto the surface of the chewing gum piece; U.S. Pat. No. 4,246,286 to Klose, et al. discloses a sweetened chewing gum composition which contains L-aspartyl-L-phenylalanine methyl ester (APM) in amounts up to 1.5% by weight of the total product. The reported improvement comprises a gum which has a pH of between 5.0 and 7.0 so that the degradation of APM to diketopiperazine is minimized and the storage stability of the gum is increased; and U.S. Pat. No. 4,122,195 to Bahoshy, et al. discloses a product and process in which L-aspartyl-L-phenylalanine methyl ester is fixed in the reaction product of a compound containing a polyvalent metallic ion, with an ungelatinized starch acid-ester of a substituted dicarboxylic acid whereby the decomposition rate of the L-aspartyl-L-phenylalanine methyl ester when employed in a chewing gum system is reduced.
U.K. Patent Application Serial No. GB 2,177,587 A, discloses a chewing gum product structured in layer form, with all of the water sensitive components of the formulation being placed in a core layer and encased in outer layers of water insensitive materials. It is also disclosed that one or more flavorants may be used in the gum base employed as the shell layers, and that the core material may contain one or more flavorings.
On the other hand, the chewing gum product of the present invention includes a coextruded or colayered gum including at least two separate portions wherein Aspartame is disposed in a portion separate and apart from those components which would degrade it, such as aldehyde-based flavorants, moisture components and other substances which would result in a pH of above about 4.5, an environment in which Aspartame is unstable.
SUMMARY OF THE INVENTION
The stabilized chewing gum product of this invention includes a first portion chewing gum composition comprising a gum base and an L-aspartic acid derived sweetener, and at least a second portion chewing gum composition comprising a gum base, at least one flavoring agent and, optionally, a moisture-containing component so that the L-aspartic acid derived sweetener of the first portion is present in the gum product substantially out of contact with the flavoring agents and moisture containing component of the second portion. In a particularly preferred embodiment, one or more organic acids are present in the portion containing the L-aspartic acid derived sweetener. The presence of the organic acid provides a pH range which increases and enhances the stability of the L-aspartic acid derived sweetener. The portions can be layers of gum composition or other distinct gum portions which maintain integrity in the gum product. The arrangement of the chewing gum product of the present invention increases the stability of the L-aspartic acid derived sweeteners.
The method of forming the stabilized chewing gum product of this invention includes providing a first portion including a gum base, an L-aspartic acid derived sweetener, and optionally, but preferably, one or more organic acids, in the absence of added aldehyde-based flavoring and moisture agents, providing at least one second portion including a gum base, flavorings and, optionally, at least one moisture-containing agent, and applying the first portion to the second portion in surface-to-surface relationship to form the stabilized gum product, whereby the L-aspartic acid derived sweetener(s) in the product is stabilized by preventing mutual contact between the L-aspartic acid derived sweetener(s) of the first portion and the flavorings and optional moisture component of the second portion, and is stabilized by the presence of the organic acids in the first portion.
The chewing gum product of the present invention exhibits a variety of advantages resulting from the improved manner in which the L-aspartic acid derived sweeteners are stabilized.
For instance, additional amounts of L-aspartyl-L-phenylalanine methyl ester (APM) are not required to be added when formulating the gum product in order to compensate for destabilization of APM so that when the gum product is being consumed, the desired concentration of APM will be available in the gum composition.
Additionally, the present gum product can include a normal and/or high moisture content without undergoing APM destabilization. Similarly, the present gum product can include aldehyde-based flavorings without suffering from the concomitant destabilization of APM.
Furthermore, the present gum product is organoleptically satisfying to the consumer, since immediate sweetness can be provided as well as sustained sweetness when, for example, encapsulated sweeteners are used in addition.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the present gum product in stick form;
FIG. 2 is a perspective view of the present gum product in chunk form;
FIG. 3 is a perspective view of the present gum product in chunk form having four separate portions;
FIG. 4 is a perspective view of the present gum product in tubular form having four separate portions; and
FIG. 5 is a perspective view of the present gum product in chunk form having four separate portions.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Description of the Portion Containing the L-Aspartic Acid Derived Sweetener
Preferably, the chewing gum composition of the first portion, i.e., the sweetener containing portion, as well as the chewing gum composition of the second portion, is substantially anhydrous. By substantially anhydrous, it is meant that there is less than about 2% by weight of moisture in the portion. Suitable chewing gum compositions having a relatively low moisture content are described in U.S. Pat. Nos. 4,514,422 to Yang et al., issued Apr. 20, 1985; 4,579,738 to Cherukuri et al., issued Apr. 1, 1986; 4,581,234 to Cherukuri et al., issued Apr. 8, 1986; and 4,587,125 to Cherukuri et al., issued May 6, 1986; the disclosures of each being incorporated herein by reference.
The gum base used may be any water-insoluble gum base well known in the art. Illustrative examples of suitable polymers in gum bases include both natural and synthetic elastomers and rubbers. For example, those polymers which are suitable in gum bases, include, without limitation, substances of vegetable origin such as chicle, jelutong, gutta percha and crown gum. Synthetic elastomers such as butadene-styrene copolymers, isobutylene-isoprene copolymers, polyethylene, polyisobutylene and polyvinylacetate and mixtures thereof, are particularly useful.
The gum base can contain elastomer solvents to aid in softening the rubber component. Such elastomer solvents may comprise methyl, glycerol or pentaerythritol esters of rosins or modified rosins, such as hydrogenated, dimerized or polymerized rosins or mixtures thereof. Examples of elastomer solvents suitable for use herein include the pentaerythritol ester of partially hydrogenated wood or gum rosin, pentaerythritol ester of wood or gum rosin, glycerol ester of wood or gum rosin, glycerol ester of partially dimerized rosin, glycerol ester of polymerized rosin, glycerol ester of tall oil rosin, glycerol ester of wood or gum rosin and partially hydrogenated wood or gum rosin and partially hydrogenated methyl ester of rosin, such as polymers of alpha-pinene or beta-pinene; terpene resins including polyterpene and mixtures thereof. The elastomer solvent may be employed in an amount ranging from about 10% to about 75% and preferably about 45% to about 70% by weight of the gum base.
A variety of traditional ingredients may be incorporated in the gum base, such as plasticizers or softeners. Examples of these ingredients include lanolin, stearic acid, sodium stearate, potassium stearate, glyceryl triacetate, glycerine, lecithin, glyceryl monostearate and the like. Natural waxes, petroleum waxes, polyurethane waxes, paraffin waxes and microcrystalline waxes may also be incorporated into the gum base to obtain a variety of desirable textures and consistency properties. Mixtures of these traditional ingredients are also contemplated. These traditional ingredients are generally employed in amounts of up to about 30% by weight, and preferably, in amounts of from about 3% to about 20% by weight of the final chewing gum product.
The sweetener containing portion of the present chewing gum product may additionally include the conventional additives of coloring agents such as titanium dioxide; emulsifiers such as lecithin and glyceryl monostearate; and additional fillers such as aluminum hydroxide, alumina, aluminum silicates, calcium carbonate, dicalcium phosphate, and talc and combinations thereof. These fillers may also be used in the gum base in various amounts. Usually, when present, these fillers are used in amounts up to about 30% by weight of said gum product. Preferably, the amount of fillers when used will vary from about 4% to about 30% by weight of the final chewing gum product.
The gum base used in the sweetener containing portion may be employed in quantities from about 5% to about 50%, preferably from 15% to about 40% and, most preferably, from about 20% to about 30% by weight of the final chewing gum product.
The sweetener containing portion of the present chewing gum product contains an L-aspartic acid derived sweetener in an amount effective to provide the level of sweetness desired. The preferred embodiment includes L-aspartyl-L- phenylalanine methyl ester (APM) as a sweetener, the preparation of which is set forth in U.S. Pat. No. 3,492,121, incorporated herein by reference. Other examples of L-aspartic acid derived sweeteners include L-α-aspartyl-N-(2,2,4,4-tetramethyl-3-thiethanyl)-D-alaninamide hydrate; methyl esters of L-aspartyl-L-phenylglycine and L-aspartyl-L-2,S,dihydrophenylglycine; L-aspartyl-2,5-dihydro-L-phenylalanine; L-aspartyl-L-(1-cyclohexy-en)alanine; and the like.
The problem with APM is that APM displays sensitivity when it is exposed to elevated temperatures, moisture, certain pH conditions and certain other food ingredients, including flavorings, especially aldehyde-based flavorings. Such exposure causes APM to break down to the corresponding diketopiperazine (DKP), which is evidenced by a proportionate decrease in sweetness.
APM, or other L-aspartic acid derived sweetener, can be employed in the sweetener-containing gum composition as a free sweetener whether used alone or in combination with other sweeteners and/or encapsulated APM. Free APM, or other L-aspartic acid derived sweetener, may be used in amounts of about 0.01% to about 2.0% by weight of the final chewing gum product. Preferably, APM is employed in an amount of about 0.01% to about 1.0% and, most preferably, in an amount of about 0.01% to about 0.4% of the final chewing gum product. Auxiliary sweeteners may be used to complement APM and may be employed in conventional amounts based on the total weight of the chewing gum product, as is standard in the art. For instance, a preparation of APM-containing sweeteners are disclosed in U.S. Pat. No. 4,556,565 to Arima et al. However, the present invention is distinguished from the disclosure of U.S. Pat. No. 4,556,565 which describes an APM-containing gum composition wherein an attempt to stabilize the APM is undertaken by replacing calcium carbonate with microcrystalline cellulose powder.
Optionally, other sweetening agents (sweeteners) can be used in conjunction with the APM or other L-aspartic acid derived sweeteners in amounts sufficient to complement the sweetness of the APM or other L-aspartic acid derived sweeteners. It is also contemplated that these other sweeteners may be used in amounts sufficient to provide a desired level of sweetness in which the level of sweetness is enhanced by the amount of APM or other L-aspartic acid derived sweeteners used. These other sweeteners include water-soluble sweetening agents, water-soluble artificial sweeteners, water-soluble sweetening agents derived from naturally occurring water-soluble sweeteners, protein based sweeteners, mixtures thereof, and the like. Without being limited to particular sweeteners, representative illustrations of these other sweeteners include:
A. Water-soluble sweetening agents such as monosaccharides, disaccharides and polysaccharides such as xylose, ribose, glucose (dextrose), mannose, galactose, fructose (levulose), sucrose (sugar), maltose, invert sugar (a mixture of fructose and glucose derived from sucrose), partially hydrolyzed starch, corn syrup solids, dihydrochalcones, monellin, steviosides, glycyrrhizin, and sugar alcohols such as sorbital, xylitol, mannitol, maltitol, hydrogenated starch hydrolysate and mixtures thereof;
B. Water-soluble artificial sweeteners such as the soluble saccharin salts, i.e., sodium or calcium saccharin salts, cyclamate salts, acesulfame-K and the like, and the free acid form of saccharin;
C. Water-soluble sweeteners derived from naturally occurring water-soluble sweeteners, such as a chlorinated derivative of ordinary sugar (sucrose), known, for example, under the product designation of sucralose; and
D. Protein based sweeteners such as thaumatin.
These other sweeteners, when used, are used in amounts effective to provide the desired end result and such amounts may vary with the sweetener selected. For example, for an easily extractable sweetener the amounts can range from about 0.01% to about 90% by weight of the final chewing gum product. The water-soluble sweeteners described in category A above can be used in amounts up to about 75% by weight of the final chewing gum product with about 25% to about 75% by weight being suitable. Some of the sweeteners in category A (e.g., glycyrrhizin) may be used in amounts set forth for categories B-D above due to the sweeteners known sweetening ability. The sweeteners in categories B-D can be used in amounts of about 0.005% to about 5.0% and preferably about 0.05% to abut 2.5% by weight of the final chewing gum product. The amounts selected for use in conjunction with the L-aspartic acid derived sweeteners are those which will provide a desired level of sweetness independent from the flavor level achieved from the flavorings used.
The sweetener containing portion of the present chewing gum product can also contain an encapsulated APM sweetener. APM may be encapsulated by a variety of coating techniques, including spray drying, coascervation, and the like. Preferably, the APM is encapsulated by a method that operates in similar fashion to fluidized bed coating processes, in that particles of APM are suspended in an apparatus that creates a strong upward air current or stream in which the particles move. The stream passes through a zone of finely atomized droplets of the coating material or encapsulant, after which the thus coated particles pass out of the upward stream and pass downward in a fluidized condition countercurrent to a flow of heated fluidized gas whereupon they are aired, and may reenter the upward-moving coating zone for a subsequent discrete coating application. The foregoing method and associated apparatus are known as the Wurster Process. The Wurster Process and its associated apparatus are set forth in detail in the following U.S. Pat. Nos.: 3,089,824,; 3,117,027, 3,196,827; 3,241,520; and 3,253,944.
The L-aspartic acid derived sweetener containing portion of the present chewing gum product also preferably contains one or more organic acids in amounts which will maintain the pH of this portion in a range of up to about 4.0 and, preferably, between a range of about 2.5 to about 3.5. The amount and type of organic acid to be employed is determined in any conventional manner, so that the pH is maintained within the desired ranges. As merely illustrative, these acids can include, but should not be limited to, malic acid, adipic acid, citric acid, tartaric acid, fumaric acid, ascorbic acid, and the like. By separating and concentrating the acids solely in the sweetener containing portion concentrations of acid can be used which will provide a stable pH environment for the L-aspartic acid derived sweetener and still yield a gum composition having low enough tartness to be palatable to the chewer. Thus, for example, organic acids used in a total amount of up to about 4% by weight of the total sweetener containing portion may prove useful with up to about 3% by weight being preferred. Usually, the amount of acid utilized is within the range of about 0.05% to about 3% by weight of the total sweetener containing portion.
Description of the Portion that is devoid of the L-Aspartic Acid Derived Sweetener
This particular portion of the present chewing gum product also includes a gum base. The preceding description regarding the gum base employed in the portion containing the L-aspartic acid derived sweetener applies equally as well herein.
Thus, in brief reiteration, the gum base is primarily fabricated from the suitable polymers described. Additionally, as previously described, the gum base can contain elastomer solvents, plasticizers, softeners, coloring agents, emulsifiers and fillers.
This particular portion of the present chewing gum product also includes flavoring components.
The flavorings employed in this portion include those known to the skilled artisan, such as, natural and artificial flavors. These flavorings may be chosen from synthetic flavor oils and flavoring aromatics, and/or oils, oleo resins and extracts derived from plants, leaves, flowers, fruits and so forth, and combinations thereof. Representative flavor oils include: spearmint oil, cinnamon oil, oil of wintergreen (methylsalicylate), peppermint oils, clove oil, bay oil, anise oil, eucalyptus oil, thyme oil, cedar leaf oil, oil of nutmeg, oil of sage, oil of bitter almonds and cassia oil. Also useful are artificial, natural or synthetic fruit flavors such as vanilla, and citrus oil, including lemon, orange, grape, lime and grapefruit and fruit essences including apple, pear, peach, strawberry, raspberry, cherry, plum, pineapple, apricot and so forth. These flavorings may be used individually or in admixture. Commonly used flavors include mints such as peppermint, menthol, artificial vanilla, cinnamon derivatives, and various fruit flavors, whether employed individually or in admixture. The flavorings are generally utilized in amounts that will vary depending upon the individual flavor, and may, for example, range in amounts of about 0.005% to about 5% by weight of the final chewing gum compositions weight and preferably about 0.2% to about 3% by weight and most preferably about 0.4% to about 2.5% by weight.
Separation of the L-aspartic acid derived sweetener into one portion and the flavorings into another portion, as stated above, results in improved stability of the L-aspartic acid derived sweetener. The improved stability is more significantly enhanced when organic acids are added to the L-aspartic acid derived sweetener portion, and such stability is more dramatically demonstrated when the flavorings (flavors) are aldehyde-based flavorings.
Examples of suitable aldehyde flavors include, but are not limited to: acetaldehyde (apple); benzaldehyde (cherry, almond); anisic aldehyde (licorice, anise); cinnamic aldehyde (cinnamon); citral, i.e., alpha citral (lemon, lime); neral, i.e., beta citral (lemon, lime); decanal (orange, lemon); ethyl vanillin (vanilla, cream); heliotropine, i.e., piperonal (vanilla, cream); vanillin (vanilla, cream); alpha-amyl cinnamaldehyde (spicy fruity flavors); butyraldehyde (butter, cheese) valeraldehyde (butter, cheese); citronellal (modifies, many types); decanal (citrus fruits); aldehyde C-8 (citrus fruits); aldehyde C-9 (citrus fruits); aldehyde C-12 (citrus fruits); 2-ethyl butyraldehyde (berry fruits); hexenal, i.e., trans-2 (berry fruits); tolyl aldehyde (cherry, almond); veratraldehyde (vanilla); 2,6-dimethyl-5-heptenal, i.e., Melonal (melon); 2,6-dimethyloctanal (green fruit); and, 2-dodecenal (citrus, mandarin); cherry; grape; strawberry shortcake; mixtures thereof; and the like.
When used, the moisture-containing component is used in amounts effective to provide the desired end result, and preferably is used in amounts such that an anhydrous chewing gum composition portion is obtained. The moisture-containing component is a material naturally containing water or a material in which water is added into the material. Examples of moisture-containing components include but are not limited to: water; hydrogenated starch hydrolysate; solutions of the other sweeteners described above; gum arabic solutions; and the like. In general, for anhydrous portions, the moisture-containing components may be used in amounts up to about 1% by weight of the final chewing gum product with a suitable range being about 0.01% to about 1% by weight. If an anhydrous portion is not contemplated then the moisture-containing component may be used in amounts up to about 20% by weight of the final chewing gum product, unless one of the other sweeteners described above and known to those skilled in the art as a high intensity sweetener (e.g., saccharin, cyclamate, acesulfame-K; glycyrrhizin, monellin, chlorinated derivative of sucrose, thaumatin, and the like) is used, in which case amounts up to about 3% by weight of the final chewing gum product may prove suitable.
Preparation of the Chewing Gum Product
The present chewing gum product is prepared by first separately preparing each of the portions described above. It is to be understood that while only two separate portions have been described, that is, the portion which contains the L-aspartic acid derived sweetener and the portion which is devoid of same, the present chewing gum product must contain both of these portions at a minimum. Other portions can be included in the final gum product. Each additional portion, however, will, of course, correspond in composition to either the portion containing the L-aspartic acid derived sweetener or the portion that is devoid of same.
After each of the respective portions have been separately prepared, in a manner which will be further understood by referring to the examples discussed hereinafter, the portions are mutually applied to each other, that is, they are colayered or coextruded in a surface-to-surface relationship.
Referring now to the drawings, illustrated in FIGS. 1 to 5 are various embodiments of the present chewing gum product. Each of the shaded portions represent the portion containing the L-aspartic acid derived sweetener, while the unshaded portion represents the portion devoid of the sweetener.
The following examples serve to provide further appreciation of the invention but are not meant in any way to restrict the effective scope of the invention. Thus, while the preceding description and the following examples focus on a bi-layered gum composition, it is to be understood that the present invention also pertains to a gum product having more than two portions which can take the form of layers or other configurations such as square or round shaped tubes, etc.
In the examples that follow substantially anhydrous chewing gum compositions were used.
EXAMPLES 1-6
The following procedure was used to form the chewing gum compositions of the examples using the formulations given in Table I.
The gum base was heated to a temperature in excess of 60° C. to reduce it to its molten state. The molten gum base was added to a standard gum mixing vessel. The gum base was reversed mixed as cold water was applied to the kettle while heating and mixing were continued. Before the gum base had achieved a temperature of 80° C., lecithin and a softener were added to the kettle and the admixture was reverse mixed for about 3 minutes. At a temperature maintained between 40°-75° C. two-thirds of the total amount of sorbitol, organic acids, which included malic acid, adipic acid and citric acid, mannitol and color, were added and forward mixed for 3 minutes. At a temperature maintained between 40°-70° C. another softener was added and forward mixed for 3 minutes, reversed mixed for 30 seconds, and then forward mixed for 30 seconds. At a temperature maintained between 30°-65° C., yet another softener was added and the admixture was forward mixed for about 2 minutes. At a temperature maintained between 30°-65° the remaining one-third of the total amount of sorbitol and still another softener were added, and the admixture was forward mixed for 4 minutes. At a temperature below the degradation temperature of encapsulated APM, encapsulated APM and the free APM were added to the designated examples, and the admixture was forward mixed for 3 minutes.
The aforedescribed procedure was employed to produce both portions. Both of the resulting admixtures for each example were removed from the vessel and placed into separate extruder chambers of a coextruder, and coextruded into a single slab which had limited surface-to-surface contact between formulas. The slab was cut and wrapped into pieces.
Table I below illustrates the percentage, by weight, of each ingredient used in each portion of the gums formed in Examples 1-6.
TABLE I__________________________________________________________________________Example 1 2* 3 4* 5 6*Flavor Cherry/Grape Regular** Strawberry ShortcakeLayers A B A B A B A B A B A B__________________________________________________________________________IngredientsGum Base 25.00 25.00 25.00 25.00 22.00 22.00 25.00 19.00 23.00 23.00 24.00 22.00Lecithin 1.00 1.00 1.00 1.00 0.80 0.80 0.50 1.10 1.00 1.00 1.00 1.00Malic Acid 0.35 0.35 -- 0.70 -- -- -- -- 0.30 0.30 0.60 --Adipic Acid 0.35 0.35 -- 0.70 -- -- -- -- 0.30 0.30 0.60 --Citric Acid 0.30 0.30 -- 0.60 0.50 0.50 -- 1.00 0.25 0.25 0.50 --Red Color 0.40 0.40 0.40 0.40 0.02 0.07 0.02 0.07 -- 0.10 -- 0.10Softeners 10.25 10.25 9.25 11.25 10.7 10.7 9.6 11.8 10.6 10.6 10.8 10.4Mannitol 15.00 15.00 15.00 15.00 15.00 15.00 15.00 15.00 15.00 15.00 15.00 15.00Cherry/Grape Flvr. 0.90 0.90 1.80 -- -- -- -- -- -- -- -- --Strawberry Short- -- -- -- -- -- -- -- -- 0.70 0.70 -- 1.40cake FlavorRegular Flavor -- -- -- -- 1.30 1.30 2.60 -- -- -- -- --Encapsulated APM 1.66 1.66 -- 3.32 1.66 1.66 -- 3.32 1.66 1.66 3.32 --Free APM 0.05 0.05 -- 0.10 0.05 0.05 -- 0.10 0.05 0.05 0.10 --Sorbitol 44.74 44.74 47.55 41.93 47.97 47.92 47.28 48.61 47.14 47.04 44.08 50.18__________________________________________________________________________ *Compositions of this invention **A bubble gum type flavor
Compositions of this invention are represented by Examples 2, 4 and 6 in which the APM and the organic acids are in one portion and the flavor is in another portion. A and B, represent the portions of each composition. In the controls, Examples 1, 3 and 5, the APM and organic acids are not separated into one portion distinct from the flavoring.
Table II below illustrates the improved stability of Aspartame when employed in the gum products of this invention, i.e., Examples 2, 4 and 6, relative to the gum products obtained in control Examples 1, 3 and 5.
TABLE II__________________________________________________________________________Storage Cond. Example 1 Example 2 Example 3 Example 4 Example 5 Example 6__________________________________________________________________________25° C.Initial 0.305 -- 0.29 -- 0.27 -- 0.29 -- 0.30 -- 0.315 --8 weeks 0.270 88.5 0.258 89.0 0.244 90.4 0.264 91.0 0.254 84.7 0.277 87.930° C.1 week 0.28 91.8 0.32 110* 0.265 98.2 0.295 102* 0.28 93.3 0.30 95.22 weeks 0.274 89.8 0.304 105* 0.242 89.6 0.288 99.3 0.272 90.7 0.290 92.14 weeks 0.275 90.2 0.278 95.9 0.244 90.4 0.272 93.8 0.264 88.0 0.289 91.88 weeks 0.242 79.3 0.248 85.5 0.206 76.3 0.280 96.6 0.223 74.3 0.245 77.837° C.1 week 0.260 85.2 0.276 95.2 0.236 87.4 0.283 97.6 0.282 94.0 0.284 90.22 weeks 0.252 82.6 -- -- 0.221 81.8 -- -- 0.254 84.6 0.294 93.34 weeks 0.234 76.7 0.238 82.1 0.202 74.8 0.216 74.5 0.236 78.7 0.260 82.5__________________________________________________________________________ *Appear to represent anomalous results
The numbers appearing in the left-hand columns represent the free APM remaining expressed as a percent of the total gum composition. The numbers appearing in the right-hand columns represent the free APM remaining expressed as a percent of the initial amount of APM utilized after a variety of time periods and temperature have elapsed.
As these data demonstrate, the chewing gum product of examples 2, 4 and 6 show improved Aspartame stability over the gum product of Examples 1, 3 and 5.
Table III below further demonstrates the improved stability of free Aspartame of the inventive gum products resulting from Examples 2, 4 and 6, relative to the gum products of Examples 1, 3 and 5.
Table III demonstrates Aspartame stability from 25° C. in a 52 week regression line (arrhenius treatment).
TABLE III__________________________________________________________________________Aspartame Example 1 Example 2 Example 3 Example 4 Example 5 Example 6__________________________________________________________________________log % Retained 1.627 1.740 1.725 1.736 1.435 1.627% Retained (52 weeks) 42 55 53 54 27 42% Retained (39 weeks) 52 64 62 63 38 52% Retained (26 weeks) 65 74 73 74 52 65__________________________________________________________________________
These data further demonstrate the improved stability of the free Aspartame in the present gum product.
The results of Example 2 in comparison to Example 1, and of Example 6 in comparison to Example 5, appear to be significantly greater than the results of Example 4 in comparison to Example 3. These results may be explained in that it is believed that the flavoring used in Examples 3 and 4 contains less aldehyde groups than the flavorings used in Examples 1 and 2 and in Examples 5 and 6.
Those skilled in the art will appreciate that, unless indicated otherwise, all percents herein are percent by weight of the final chewing gum composition (product). Also, the total amount of all ingredients (components) used in the chewing gum compositions of this invention equals 100%.
Thus, while there have been described what are presently believed to be the preferred embodiments of the invention, those skilled in the art will realize that changes and modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the true scope of the invention. | A stabilized chewing gum product containing an L-aspartic acid derived sweetener in its free form and method for manufacture thereof are disclosed. The chewing gum product includes at least two portions, one of which includes, in its free form, Aspartame (APM) as an artificial, low calorie sweetener. Also included in the APM-containing portion can be an organic acid which will maintain the pH of the portion at a level conducive to maintaining the stability of APM. A second portion can include flavoring agents, and optionally, at least one moisture-containing agent. The portions are arranged in surface-to-surface relationship whereby contact between the APM and the flavorings and/or moisture-containing agent of the second portion is substantially reduced. The stability of APM and, consequently, of the chewing gum product is substantially increased. | 8 |
This application is a continuation-in-part of Ser. No. 8/418,716 filed Apr. 7, 1995 now U.S. Pat. No. 5,612,040.
BACKGROUND OF THE INVENTION
1. Field of the Invention
Foot-and-mouth disease virus (FMDV) is responsible for one of the most devastating and contagious diseases in cattle and other cloven-hooved animals, affecting over 100,000 animals a year and resulting in significant economic loss. The disease occurs in many areas of the world outside the United States where vaccination programs have been largely effective. There are risks associated with the vaccines currently in use, however, and at present FMDV vaccines cannot be produced in the United States despite the continued threat of the introduction of this agent into the country. It is feared that the virus used to make vaccines could escape from containment and cause disease. Moreover, the failure to completely inactivate the virus during vaccine preparation has led to accidental outbreaks of infection. In addition, there is considerable antigenic variability among the various serotypes, thus some viruses may not be recognized by the vaccinated animals. Furthermore, frequent revaccination has been required in order to maintain protective immunity utilizing conventional vaccines containing virus attenuated by chemical inactivation (Bachrach, H. L. 1968. Annu. Rev. Microbiol. vol. 22, pp. 201-244). There is thus a strong incentive to develop an effective vaccine which eliminates the threat of infection due to the accidental outbreaks associated with vaccine production and administration. A new and safer genetically-engineered vaccine against FMDV which provides effective protection but is not infectious, and thus does not present the risk of causing accidental infections, is the subject of related patent application Ser. No. 08/418,716 now U.S. Pat. No. 5,612,040. This invention relates to a genetically-engineered cell line for the propagation of the mutant virus.
2. Description of the Related Art
In an effort to overcome the deficiencies of conventional virus vaccines, synthetic vaccines have been investigated. Identification of a flexible loop exposed on the virus surface as the main antigenic site of FMDV (site A) prompted the investigation of the use of various peptide fragments within site A to stimulate immunological responses. For example, the conserved tripeptide Arg-Gly-Asp (RGD) was evaluated for its ability to stimulate the production of neutralizing antibodies in rabbits or guinea pigs (Novella et al. 1993. FEBS Letters. vol. 330, no. 3, pp. 253-259).
Attempts to produce attenuated virus vaccines by genetic engineering were also carried out. Rieder et al. (1993. J. Virol. vol. 67, no. 9, pp. 5139-5145, herein incorporated by reference), for example, evaluated the role of the poly(C) tract found at the 5' end of the FMDV genome. Cardioviruses having shorter-than-natural poly(C) tracts had been shown to be dramatically attenuated; however, the poly(C) tract length of FMDV showed no effect on virulence when tested in mice.
A non-infectious form of the FMD virus consisting of a genetically-engineered receptor-binding site-deleted virus particle has been described in related U.S. Pat. No. 5,612,040, supra. The receptor binding site-deleted particle, which lacks the three amino acids of the tripeptide RGD in the capsid protein VP1 is not infectious for cells in culture or for animals; however, the RGD-deleted virion is able to induce a protective immune response in cattle U.S. Pat. No. 5,612,040, supra; McKenna et al. 1995. J. Virol. vol. 69, p. 5787). Since the virus cannot infect cells in culture or animals, production of the virus has been limited to the transfection of cells capable of allowing assembly of the mutant virus from the vector containing the mutant RNA, allowing RNA to replicate in the transfected cells and harvesting the mutant virus particles from the cell cultures. Although effective, it is expensive to produce commercial quantities of virus in this manner. Thus a means for the production of virus in larger quantities was needed.
SUMMARY OF THE INVENTION
To overcome this problem, we have now engineered a cell line capable of growing the virus which has a novel cellular receptor molecule derived from a recombinant DNA produced by fusing the gene for the active site of an antibody specific for the virus to the gene for a normal cell surface protein. The chimeric protein thus produced confers viral susceptibility to cells that normally lack the receptor, thereby producing a cell line useful for the mass cultivation of the receptor-deleted mutant virus. In accordance with this discovery, it is an object of the invention to provide a novel genetically-engineered cell line susceptible to infection by receptor-deleted FMD virus particles and capable of allowing replication of the virus to occur.
It is another object of the invention to provide a method of making the novel genetically-engineered cell line.
Other objects and advantages of the invention will become readily apparent from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the amino acid sequences of the G-H loop of the wild-type and mutant genomes. Dashes designate identity with wild-type.
FIG. 2 shows the position of mutated sequences on the FMDV genome. CDNA fragments used to engineer mutant viruses are shown above the FMDV portion of the plasmid pRMC 35 . UTR, untranslated region; oligos, oligonucleotides.
FIG. 3 shows a method for single chain antibody production.
FIG. 4 shows production of scAb-1CAM-1 receptor.
FIG. 5 shows one-step growth curves of wild-type FMDV type A12 released from infected BHK, CHO-WT, and CHO 11.1 cells. Arrow indicates the time of low pH rinse, see Table 3.
FIG. 6 shows plaques formed by the RGD-FMDV on monolayers of CHO 11.1 cells. Cells were infected with dilutions of virus, overlayed with tragacanth, and stained 72 hrs post infection by standard methods.
FIG. 7 shows A260 profile of sucrose density gradients prepared from RGD-virus grown in CHO 11.1 cells.
DETAILED DESCRIPTION OF THE INVENTION
A vaccine is defined herein as a biological agent which is capable of stimulating a protective immune response in an animal to which the vaccine is administered.
Foot-and-mouth disease virus is an RNA virus of the Aphthovirus genus of the family Picornaviridae. There are several known serotypes occurring in Europe (A, O and C
TABLE 3______________________________________Growth of wild-type FMDV in wild-type and transfected CHO cellcultures.CHO cell culture.sup.1 Virus yield (pfu/ml).sup.2______________________________________pscAb/ICAM-1#11-transfected 9.5 × 10.sup.5pV.sub.H K#2-transfected 2.0 × 10.sup.3wild-type cells 1.6 × 10.sup.3______________________________________ .sup.1 Cells were secondpassage, G418 selected cells or wildtype cells. .sup.2 Cells were grown in 35 mm diameter dishes, inflected at a multiplicity of infection (moi) of 20 for one hour at 37° C., rinsed in MESbuffered saline, pH 6.0 to remove input virus, incubated overnight at 37° C., lysed by freeze/thaw, and virus titers determined by plaque assay (Rieder et al., 1993. J. Virol. 67, 5139).
serotypes), southern Africa (SAT 1, SAT 2 and SAT 3) and the Asia 1 serotype, having distinct variations both immunologically and genetically. The virion consists of a single-strand, positive-sense RNA genome packaged in an icosahedrally symmetric shell composed of 60 copies each of four structural proteins, VP1-4. Analysis of the three-dimensional structure of FMDV revealed a prominent surface feature formed by a flexible loop between the G and H β strands of VP1 (G-H loop) (Acharya et al. 1989. Nature. vol., 337, p. 709; Parry et al. 1990. Nature. vol. 347, p. 569; Logan et al. 1993. Nature. vol. 362, p. 566). Contained within this loop is the highly conserved RGD tripeptide sequence which has been identified as the main antigenic site. In addition, synthetic peptide inhibition studies have suggested that the site is also involved in receptor binding activity (Fox et al. 1989. J. Gen. Virol. vol. 70, p. 625; Baxt and Becker. 1990. Virus Genes. vol. 4, p. 73).
Studies were carried out in order to further elucidate requirements for cell binding, immunogenicity and the infectious ability of the virus. For this purpose, mutant viruses were prepared from a full-length infectious cDNA clone of FMDV type A 12 (Rieder et al., supra), where amino acid substitutions were made either within or bordering the conserved RGD sequence (as described in Mason et al. 1994. PNAS. vol. 91, pp. 1932-1936, herein incorporated by reference).
Full-length mutant cDNA molecules having sequence changes as shown in FIG. 1 in codons 143-147 of VP1 were produced. Antigenic properties of mutant viruses produced from the cDNAs were evaluated by reacting the viruses with a panel of monoclonal antibodies which recognized epitopes either within or outside the G-H loop. Results, shown in Table 1, indicated that conservative changes within the G-H loop did not induce major changes in the antigenic structure of the virion.
TABLE 1______________________________________ AntibodySequence * Reactivity** Cell Binding, % +______________________________________VRGDF (Wild-type) + 65DRGDF + 28PRGDF + 61VRGDK‡ ± 63VKGDF + 2VRGEF + 2VKGEF + 2______________________________________ *Amino acids 143-147 of VP1 (underline denotes mutations) **Determined by radioimmunoprecipitation: +, strong reaction, ±, weak reaction + Determined at a constant virus/cell ratio (1000:1) ‡Also contains a leucine substitution for a proline at positio 152 (see FIG. 1)
Cell binding studies utilizing the mutant viruses were also carried out. Binding of the viruses having mutations bordering the RGD sequence to baby hamster kidney (BHK) cells were retained; however, cell binding was somewhat reduced in two of the three mutants and reduced by about 50% in the third. Those mutants having mutations within the RGD sequence did not bind to BHK cells, however, indicating that they were defective with respect to binding and adsorption into the cell (Table 1).
Transcripts of the various mutant sequences were evaluated for their ability to cause cytopathic effects (CPE) and produce plaques following transfection into BHK cells. Those transcripts having mutations bordering the RGD sequence caused CPE, plaques and specific infectivities similar to transcripts from the parental infectious clone (Table 2), indicating that mutations encoded by these RNAs had no effect on viability.
The mutant viruses were found to be antigenic but not infectious, however single base mutations have been known to revert to wild-type. Tests were thus carried out to determine if reversions occurred as expected for the mutant viruses. Cells transfected with mutant RNA containing KGD and RGE mutations were found to produce 10,000-fold less infectious virus than cells transfected with RNA produced from the wild-type virus. Sequence analysis of selected plaques harvested from transfected cells confirmed that those viruses found to be infectious had regained the RGD coding sequence. As also expected, the double mutation KGE did not appear to revert to wild-type since no plaque-forming units were recovered from cells transfected with the double-mutant RNA. In addition, all of the KGD and RGE revertants produced wild-type plaques, and a detailed examination of cell binding by one of these revertants revealed that it bound to cells as well as the wild-type virus, conclusively showing that the RGD sequence is required for adsorption to and infection of BHK cells.
TABLE 2______________________________________Sequence* Specific Infectivity**______________________________________VRGDF (Wild-type) 4.2 × 10.sup.3DRGDF 6.6 × 10.sup.3PRGDF 2.0 × 10.sup.3VRGDK 1.4 × 10.sup.3VKGDF <1VRGEK <1VKGEF <1______________________________________ *Amino acids 143-147 of VP1 (underline denotes mutation) **Specific Infectivity of transcripts (plaqueforming units/μg) determined using Lipofectin
Since the threat of reversion to wild-type is clearly not a desirable property for a virus contemplated for use as a vaccine, especially one having virulence such as that exhibited by FMDV, efforts to create a stable non-infectious FMDV were begun. A virus was constructed in which the entire RGD sequence was deleted, and tests were carried out to determine the effect of the deletion on the conformation of the capsid structure, and thus the antigenicity of the virus. A genome-length cDNA (Rieder et al., supra) was prepared from the wild-type RNA, and the codons encoding the wild-type amino acid sequence GVRGDF were replaced with codons for AsnPro (NP). Synthetic RNA transcripts were constructed from this CDNA and introduced into BHK cells (Mason et al., supra). Cells transfected with the synthetic RNA produced levels of virus particles similar to those produced by cells transfected with wild-type RNA, and preliminary experiments showed that these particles did not bind to cells, were non-infectious, and were recognized by monoclonal antibodies specific for four different epitopes on FMDV type A 12 (Baxt et al. 1984. J. Virol. vol. 51, p. 298; Baxt et al. 1989. J. Virol. vol. 63, p. 2143). One of these epitopes included portions of the G-H loop, indicating that the deletion had little, if any, effect on the antigenic structure of the RGD-deleted virus.
Tests were also carried out to demonstrate that the RGD-deleted mutant viruses would not revert to wild-type with respect to infectivity or virulence (see Example 2). RGD-deleted mutant virus preparations were used to inoculate BHK cells and baby mice. No CPE were observed in BHK cell cultures which had been incubated for 72 h, and a plaque assay carried out on passaged cells did not reveal any infectious agent. In addition, 20 7- to 10-day-old mice were inoculated, and none of the mice died or showed any signs of infection.
Virulence of the mutant virus was tested by inoculating swine with either mutant or wild-type virus (see Example 3). Virus was inoculated into the coronary band and the dermis of the snout of two adult Yorkshire swine, and the animals were observed for signs of FMD for 2 weeks. Symptoms of classical FMD were observed in the animal having received the wild-type inoculation, whereas the animal receiving mutant virus inoculations showed no signs of disease.
Tests were also carried out to demonstrate the efficacy of the vaccine (see Example 4). A vaccination/challenge study with nine 18- to 20-month-old steers was conducted. Three steers were mock vaccinated, three animals were vaccinated with a conventional inactivated wild-type virus and the remaining three animals were vaccinated with the mutant RGD-deleted virus. The animals were observed for signs of disease for 4 weeks, and none showed any development of disease.
To further test the effectiveness of the mutant virus, the nine animals were subsequently combined in a single room and exposed to a pig which had developed severe clinical manifestations of FMD. The cattle were examined daily for signs of the disease. All six vaccinated animals were protected whereas all three mock-vaccinated animals demonstrated clinical FMD within 7 days of exposure to the infected pig.
Preparation of the mutant virus is carried out by conventional genetic engineering techniques which are well-established in the art (as described, for example, in Current Protocols in Molecular Biology. 1994. Ausubel et al., eds. J. Wiley & Sons, NY). The preparation steps include 1) synthesizing cDNA from infectious RNA, 2) replacing the sequences coding for GVRGDF with NP, 3) transcribing RNA containing the deleted sequences from the mutant CDNA, 4) cloning the mutant synthetic RNA into an effective vector, 5) transfecting cells capable of allowing assembly of the mutant virus from the vector containing the mutant RNA, 6) allowing the RNA to replicate in the transfected cells in order to produce mutant virus particles and 7) harvesting the mutant virus particles from the cell cultures. A complete description of the method of preparing the mutant virus is contained in parent application now U.S. Pat. No. 5,612,040, supra, herein incorporated by reference.
Synthetic mutant RNAs are transcribed and introduced into cells capable of allowing replication of the mutant viruses. BHK cells have been found effective for this purpose; however, other cell lines such as Chinese hamster ovary (CHO) are also useful. The cells may be effectively transfected using Lipofectin (GIBCO/BRL) or electroporation as described in Mason et al., supra. Using the electroporation method described in Example 1, large numbers of cells transfected with the RGD-deleted RNA are produced, cultured and mutant virus particles are found in the culture medium. Any effective culture medium may be used, for example Eagle's minimum essential medium with 10% calf serum and 10% tryptose phosphate broth, supplemented with antibiotics. The mutant virus may then be harvested from the cultures and purified for use as a vaccine. While this method is effective for producing the novel virus, utilization of the genetically-engineered cell line described herein is advantageous in that the production of larger quantities of virus is facilitated.
The first step of infection of cells in culture or in animals by FMDV is the attachment of the virus to specific cell surface molecules. An RGD-specific cell surface integrin, alphav/beta3, is the receptor for type A 12 FMDV on cultured cells (Berinstein et al. 1995. J. Virol. vol. 69, p. 2664), consistent with the finding that the RGD-deleted virus cannot bind to or infect cells (McKenna et al., supra).
Since initiating the infectious cycle requires the binding of the virion to the surface of susceptible cells (Mason et al. 1993. Virol. vol. 192, p. 568), a cell surface receptor composed of a well-characterized cell surface molecule and the virus binding end of an antibody specific for FMDV was engineered, using standard molecular biology methods (as described, for example, in Ausubel et al., supra).
The cell line is prepared essentially by carrying out the following steps:
1) selecting an effective cell line;
2) selecting a cell surface protein and obtaining the DNA which encodes that protein;
3) selecting an antibody specific for FMDV and obtaining the DNA which encodes that antibody;
4) fusing the two DNAs for form a chimeric DNA;
5) inserting the chimeric DNA into a eucaryotic expression vector;
6) transfecting the selected cell line; and
7) testing the tranfected cells to determine if chimeric DNA has been incorporated.
In selecting an effective cell line, while not required, a cell line which is not susceptible to infection by FMDV is advantageous in that selection and testing of transformed cells is facilitated.
Specifically, the cDNAs for the variable (virus-binding) domains of the messenger RNAs (mRNAs) encoding the heavy and light chains of an FMDV-specific monoclonal antibody (MAb) were amplified (FIG. 3). While any monoclonal antibody specific for FMDV is considered useful for this purpose, the MAb 2PD11 described by Baxt et al. was utilized (Baxt et al., 1984, supra; Baxt et al., 1989, supra). Initially, the variable V region of the heavy chain and the V and constant C regions of the light chain were amplified, then assembled into the gene for a single-chain antibody molecule (scaB) in a bacterial plasmid (FIG. 3); He et al. 1995. Immunol. vol. 84, p. 662). Bacteria carrying this plasmid were induced to produce the gene product, and preparations of the induced bacterial cultures were tested for their ability to immunoprecipitate radiolabeled virus particles. In these tests, the scAb was shown to be active.
The next step was fusion of the scAb CDNA to the CDNA for intracellular adhesion molecule 1 (ICAM-1), a well-characterized cell surface molecule known to serve as the receptor for another group of picornaviruses, the rhinoviruses (Staunton et al. 1989. Cell. vol. 56, p. 849; Tomassini et al. 1989. PNAS. vol. 86,j p. 4907). Using standard techniques (Ausubel et al., supra), the two cDNAs were fused and inserted into the eucaryotic expression plasmid, pcDNA3 (Invitrogen, San Diego, Calif.) behind a cytomegalovirus (CMV) promoter and an IgG signal sequence, and in front of a bovine growth hormone polyadenylation signal (FIG. 4). While the above conditions have proven effective, the selection of alternative cell surface proteins, expression plasmids, promoters, etc. are well within the level of skill in the art.
The plasmid harboring the scAb-ICAM-1 fusion (designated pscAb-ICAM-1#11) was transfected into Chinese hamster ovary (CHO) cells (Mason et al., 1993, supra), using Lipofectin (Life Technologies, Inc., Gaithersburg, Md.). Transformed cells were selected in the presence of 0.6 mg/ml of the eucaryotic antibiotic, G418 (Life Technologies, Inc.) using standard CHO cell propagation methods (Mason et al., 1993, supra). Following two passages in G418, cultures prepared from cells transfected with pscAb/ICAM-1#11 were able to replicate FMDV, whereas wild-type CHO cells, or cells transfected with the plasmid encoding only the scAb (designated Pv H K#2) were not susceptible to infection (Table 4). Although these results provided the first evidence that the scAb/ICAM-1#11 molecule could serve as an FMDV receptor, the titers of virus recovered from the pscAb/ICAM-1#11-transfected cultures were much lower than those obtained in previous studies of CHO cells expressing the Fc receptor and infected with antibody-complexed virus (Mason et al., 1993, supra).
The lower-than-expected titer of virus harvested from these cultures was consistent with the fact that the type A 12 virus did not kill all of the cells in these cultures, suggesting that not all of the cells in the culture were expressing functional scAb-ICAM-1 receptors. Therefore, single-cell clones were prepared from these transfected cultures and tested for their ability to be killed by virus. These experiments identified several clones that showed nearly uniform virus-induced cell death, or cytopathic effect (CPE), when infected with virus. One transfected CHO cell clone, designated SHO 11.1 was expanded and further tested.
One-step growth curves with type A 12 confirmed that the CHO 11.1 cell line produced high titers of virus, whereas wild-type CHO cells did not (FIG. 5). The amount of virus recovered from this cell line was similar to that recovered from infected BHK cells (FIG. 5). Furthermore, wild-type virus was able to form plaques on the CHO 11.1 cell line, whereas a previously
TABLE 4______________________________________Plaque-forming ability of wild-type type A12 FMDV and B2PD.3on CHO11.1 and BHK cells. titer in pfu/ml.sup.avirus CHO 11.1 BHK______________________________________wild-type FMDV 2.7 × 10.sup.7 4.5 × 10.sup.8B2PD.3.sup.b 5 × 10.sup.2c 1.0 × 10.sup.8______________________________________ .sup.a Titers determined by staining monolayers at 2 days post infection. .sup.b 2PD11 MAb escape mutant (see Baxt et al., 1989). .sup.c Diffuse plaques.
TABLE 5______________________________________ Neut titer Response to challengeAnimal Vaccine (log.sub.10 PRN.sub.70) Fever Lesions______________________________________57 <0.7 + +109 No vaccine <0.7 + +148 <0.7 + +15 3.4 - -103 RGD-deleted 2.5 - -143 2.5 - -21 2.5 - -50 BEI-inactivated 2.8 - -101 2.2 - -______________________________________
characterized 2PD11 monoclonal antibody escape variant B2PD.3 (Baxt et al., 1989, supra) could not (Table 4).
Since the portion of the virus that binds to the natural cellular receptor is distinct from the site recognized by 2PD11, which is in the G-H loop of the capsid protein VP3 (Baxt et al., 1989, supra), tests were carried out to determine if the RGD-deleted deleted type A 12 virus (McKenna et al., supra; U.S. Pat. No. 5,612,040, supra) was able to infect the CHO 11.1 cells. FIG. 6 shows that the RGD-deleted virus was able to form plaques on these cells, consistent with the findings that the virus caused uniform CPE in this cell line. Furthermore, standard methods of virus cultivation yielded high levels of the RGD-deleted virus (FIG. 7). Data shown in FIG. 7 correspond to a production of over 1.5 μg purified RGD- virus from 10 6 CHO 11.1 cells, a value comparable with the 1.1 μg yield of purified wild-type A 12 virus from 106 BHK cells. Moreover, when 1×10 7 plaque forming units (pfu) of the CHO 11.1-propagated RGD-deleted virus was inoculated into the tongue of a bovine (as described by Cottral et al., 1965. Bull off. Int. Epiz. vol. 63, p. 1607), no lesions were formed, and the animal did not display fever or lameness, indicating that the RGD-deleted virus propagated by this method was over 10 6 -times less infectious in bovines than type A 12 virus (Cottrall et al., supra).
It has thus been shown that the scAb-ICAM-1-expressing cells are capable of producing large amounts of the RGD-deleted virus particles obtained from cells transfected with the RGD-deleted full-length RNA (U.S. Pat. No. 5,612,040, supra; McKenna et al., supra). The scAb-ICAM-1 plasmid is specific for the type A 12 virus, therefore antibodies used to manufacture receptors for other serotypes and subtypes of FMDV may need to be specific for those particular types. Furthermore, the selection of ICAM-1 as the cell surface protein is not considered an essential requirement for the production of a viable genetically-engineered receptor, i.e. any effective cell surface protein would be useful. Moreover, any effective eucaryotic expression plasmid is useful for transfection and expression of the receptor. Alternative methods (e.g., stable transformation by DNA integration) can also be used to generate cell lines expressing chimeric antibody-based receptors that will function for the replication of the receptor binding site-deleted virions. In addition, the cells may be cultured by conventional incubation techniques which are known in the art for the particular wild-type cell utilized. Mutant virus is harvested by collecting the culture media and separating the virus from the media.
Vaccines are prepared for inoculation by mixing an effective immunization dosage of the mutant virus in a pharmaceutically acceptable carrier or diluent, such as physiological saline or tissue culture medium. An effective immunization dosage is defined as that amount which will induce immunity in an animal against challenge by a virulent strain of FMDV, and immunity has been considered having been achieved when the level of protection for the immunized population is significantly higher than that of an unvaccinated control group. An effective dosage is easily determined by one of skill in the art for the particular animal of interest by administering varying amounts of the vaccine preparation to test animals and observing the dosage at which protection has been achieved.
In addition, appropriate adjuvants as known in the art may also be included in the vaccine formulation.
The following examples are intended only to further illustrate the invention and are not intended to limit the scope of the invention as defined by the claims.
EXAMPLES
Example 1
Preparation of Synthetic Mutant FMDV
FMDV RNA is isolated and purified from FMDV and used to produce cDNA by reverse transcription using AMV reverse transcriptase (Boehringer Mannheim) or Moloney murine leukemia virus (MMLV) reverse transcriptase (GIBCO/BRL). Mutations in the cDNA molecule are carried out according to the method presented in FIG. 2. Double-stranded DNA is then produced by filling in with DNA-dependent DNA polymerase and is cloned into the PGEM plasmid. Plasmids containing virus cDNAs are identified and assembled into genome-length cDNA molecules and placed under the control of the T7 bacteriophage polymerase promoter. Plasmid DNA molecules containing the full-length cDNA are purified from cultures of E. coli which harbor the plasmids, then used as a template for T7 RNA polymerase to produce synthetic genome-length RNAs containing the RGD deletion in the viral genome.
Electroporation is carried out by mixing 0.8 ml BHK cells at 3×10 7 cells per ml of Ca 2+ - and Mg 2+ -free phosphate buffered saline with 10 to 20 μg of RNA in a 0.4-cm cuvette, pulsed twice at 1500 V and 14 μF in an IBI Gene Zapper (IBI, New Haven, Conn.), diluted with growth medium (Eagle's MEM, 10% calf serum) and incubated in culture plates for 2-4 hours prior to removal of unattached cells and incubation overnight at 37° C.
The virus particles present in the culture fluid are harvested from the BHK cell cultures, concentrated by polyethylene glycol precipitation and further purified by sucrose density gradient centrifugation (Baxt et al., 1984 and 1989, supra) .
The amount of virus present in these partially purified preparations was estimated by comparison of the radioactive signals obtained on Western blots (Towbin et al. 1979. PNAS. vol. 76, p. 4350) with two-fold dilutions of a known concentration of wild-type virus, detected using polyclonal guinea pig serum specific for FMDV and 125 I-labeled protein A (NEN, Boston, Mass.). Approximately 1 μg of partially purified RGD-deleted virions could be obtained from 6×10 6 transfected cells.
Example 2
Inoculation into BHK Cells and Mice
BHK cells and baby mice were inoculated with the RGD-deleted virus preparations in order to demonstrate that the RGD-deleted virus would not regain its infectivity or virulence. Five hundred ng of RGD-deleted virus were diluted in culture media, inoculated into cultures of BHK cells, and incubated for 72 h at 37° C. Although no cytopathic effect (CPE) was visible at this time, the sample was lysed by freeze-thaw, and passaged onto fresh cells. A plaque assay of this second passage material on BHK cells did not reveal any infectious agent. One hundred ng of RGD-deleted virus were inoculated intraperitoneally (IP) into 20 seven- to ten-day-old mice. None of these mice died or showed any signs of infection. One hundred ng of a wild-type virus prepared from cells transfected with RNA derived from the wild-type genome-length cDNA, pRMC 35 (Rieder et al., supra), is equivalent to 1.2×10 6 mouse LD 50 . These results demonstrate that the RGD-deleted virus is attenuated greater than 1×10 6 fold relative to wild type.
Example 3
Inoculation of Swine
Two μg of either wild-type or RGD-deleted virus were inoculated into the coronary band and the dermis of the snout of two adult Yorkshire swine. The animals were observed for signs of FMD for 2 weeks. The animal receiving 2 μg of wild-type virus developed classical FMD (fever and lameness with vesicles on all four feet and the snout) within 5 days of inoculation, whereas the animal inoculated with 2 μg of the RGD-deleted virus did not show any signs of disease. As expected, radioimmunoprecipitation analyses of serum collected 28 days postinfection from the animal inoculated with the wild-type virus revealed strong reactivity to structural proteins as well as the non-structural proteins 3D and 2C, indicating that the virus had replicated in the animal (Berger et al. 1990. Vaccine. vol. 8, p. 213). In contrast, the 28-day postinoculation sera obtained from the pig inoculated by this route with the RGD-deleted virus showed very low levels of reactivity with structural proteins, and no detectable reactivity with non-structural proteins, indicating that the RGD-deleted virus did not replicate in this animal (Berger et al., supra).
Example 4
Inoculation of Cattle
To test the usefulness of the RGD-deleted virus as a vaccine, a vaccination/challenge study with nine 18- to 20-month-old Hereford steers was conducted. Three steers were mock vaccinated with a tissue culture media/mineral oil emulsion, three animals were vaccinated with sucrose gradient-purified, binary ethylenimine (BEI)-inactivated (H.G. Bahnemann. 1975. Arch. Virol. vol. 47, p. 47) wild-type virus emulsified in oil, and the remaining three animals were vaccinated with an oil emulsion containing RGD-deleted virus. Animals were observed for signs of FMD for 4 weeks, and in that time none of the animals developed fever or vesicles of FMD. Four weeks postvaccination, serum was collected from all nine animals, and tested for its ability to neutralize the virus in vitro. These assays showed that the RGD-deleted virus was indistinguishable from the BEI-inactivated preparation in its ability to elicit neutralizing antibodies in cattle (Table 5).
The nine animals listed in Table 5 were combined in a single large room and exposed to a pig which had developed severe clinical manifestations of FMD after infection with a virulent cattle-passaged strain of FMDV type A 12 (Vallee strain 119, cattle passage 78; kindly provided by Dr. J. House). The cattle were examined daily for onset of clinical signs (lameness, vesicle formation on the tongue, or fever). If temperatures over 39° C. were noted, the animals were sedated and examined closely for vesicular lesions on their feet and in their mouths. All six vaccinated animals were protected from clinical disease, whereas all three mock-vaccinated animals demonstrated clinical FMD with fevers (3 days over 40° C.) and lesions on the tongue and all four feet within 7 days of exposure to the infected pig.
Effectiveness of the vaccine was further evaluated by determining if viral challenge had produced immune responses to viral antigens, i.e. by comparing the ability of pre- and postchallenge sera to precipitate viral proteins from radiolabeled infected cell lysates. For one animal (#143), a weak reaction to protein 3D was observed in prechallenge sera, consistent with the fact that antibodies to 3D are often observed in sera from vaccinated animals (Berger et al., supra). Antibodies to non-structural proteins 2C, 3AB and 3C were present in postchallenge sera of mock-vaccinated animals. Based on previously established criteria (Berger et al., supra), the presence of antibodies to two or more of these antigens demonstrates extensive viral replication, consistent with the observed clinical signs in these animals (Table 6). Several minor differences between pre- and postchallenge sera were also noted among the six vaccinated animals, and in several cases antibodies to 3D were detected in postchallenge sera. However, following challenge none of the vaccinated animals developed antibodies to 2C, 3AB or 3C, indicating that vaccination had prevented, or severely limited, viral replication (Berger et al., supra). Interestingly, one of the BEI-inactivated vaccine-vaccinated animals (#101) showed an increase in antibodies to structural proteins and the appearance of reactivity with 3D following challenge, suggesting that limited, but clearly detectable, viral replication had taken place in the face of challenge in this animal. The possibility that virus replication occurred in this animal is consistent with the finding that this animal showed the lowest prechallenge titer of neutralizing antibodies (Table 5).
This challenge study demonstrates that the RGD-deleted vaccine performed as well as, or exceeded, the accepted BEI-inactivated vaccine with respect to protection from challenge, generation of serum neutralizing antibodies, and generation of an immune response which restricts replication of the virus upon challenge. This is the first demonstration that a safe and effective vaccine can be prepared by genetically removing the cell binding site from a virus.
Example 5
Growth of Wild-Type FMDV in Cell Cultures
Transfected and wild-type cell cultures as shown in Table 3 were second-passage, G418-selected cells or wild-type cells. Cells were grown in 35 mm Petri dishes, infected at a multiplicity of infection (moi) of 20 for one hour at 37° C., rinsed in MES-buffered saline, pH 6.0 to remove input virus, incubated overnight at 37° C., lysed by freeze/thaw and titers determined by plaque assay. Virus yields (pfu/ml) are shown in Table 3.
All references cited hereinabove are herein incorporated by reference. | A method of making a genetically-engineered cell line which is susceptible to infection by foot-and-mouth disease virus and allows the virus to replicate is disclosed. The method involves fusing the DNA encoding ICAM-1 with the DNA encoding an antibody specific for foot-and-mouth disease virus and expressing the resulting chimeric cell surface receptor protein. The chimeric cell surface receptor protein allows foot-and-mouth disease virus to bind, leading to subsequent infection and replication of foot-and-mouth disease virus. A genetically-engineered cell which expresses the chimeric cell surface receptor protein is also claimed. | 2 |
BACKGROUND OF THE INVENTION
The present invention provides an adjustable roller assembly for doors which slide on tracks. The adjustment mechanism can be used to take up slack after the door is installed on a track. Numerous arrangements of this general type are shown in U.S. Pat. Nos. 2,990,567, 3,237,238, 3,716,890, 4,134,178, 4,189,870 and 4,353,186. None of these patents discloses the features of the present invention.
SUMMARY OF THE INVENTION
The present invention provides an adjustable roller assembly for sliding doors. The assembly includes a housing adapted to be mounted in a recess provided at the upper or lower edge of a sliding door. The housing may be snap-fit into the slot in the door edge. The housing defines a cavity therein which is open at the lower end thereof. A roller carrier is mounted in the cavity and is vertically adjustable with respect to the housing. The roller carrier defines circular flanges at its lower end. A roller having an integral hub is rotatably mounted in the carrier, the hub supported by the circular flanges. A camming element associated with the roller carrier is disposed at the upper end of the housing. The camming element is provided with gear teeth which engage and cooperate with a threaded stem extending through the top of the housing. One end of the threaded stem extends through the side of the door. A slot adapted to receive a screwdriver is provided in the end of the stem. Vertical adjustment of the roller with respect to the housing may be achieved by rotating the stem which rotates the camming element and effects vertical adjustment of the roller carrier and roller.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view, partially broken away, of the roller assembly of the present invention installed in a door frame with the roller raised vertically with respect to the assembly housing.
FIG. 2 is a cross-sectional side view taken along line 2--2 shown in FIG. 1.
FIG. 3 is a front view, partially broken away, of the roller assembly shown in FIG. 1 with the roller lowered vertically with respect to the assembly housing.
FIG. 4 is a bottom view of the slot in the door frame into which the roller assembly of the present invention is inserted.
DETAILED DESCRIPTION OF THE INVENTION
An adjustable roller assembly, generally designated by the numeral 10, is shown in FIGS. 1-3. The roller assembly 10 is adapted to be mounted in a recess or slot 12 provided in an upper or lower edge of a door frame 14 for sliding on a track 16 extending the width of the door frame. The roller assembly 10 in FIGS. 1-3 is shown installed in the lower edge of a door frame 14.
The door frame edge defines a generally inverted U-shaped recess 18 having a flat bottom surface 18a, shown in FIG. 4, and a pair of side walls 18b, best shown in FIG. 2, depending downwardly therefrom. The slot 12 is defined in the flat surface 18a. As best seen in FIG. 4, each end of the slot 12 defines a pair of first shoulders 12a and a pair of second shoulders 12b. Defined between each pair of second shoulders 12b is a generally arcuate-shaped notch 19. The significance of the configuration of the slot 12 will become apparent below.
The roller assembly 10 includes a housing 20 comprising a pair of opposing corresponding walls 22 joined together in any appropriate manner, as for example, by pins 21. In FIG. 2, both side walls 22 are shown, but in FIGS. 1 and 3 the front side wall has been removed to show the inner components of the roller assembly. The upper end of the housing 20 is narrower than the lower end such that the edges diverge slightly from top to bottom. Each side wall 22 defines a generally arcuate-shaped slot 24 at the bottom thereof, the slot 24 being open at the bottom. The housing 20 defines a cavity 26 therein and has an opening 28 at the lower end thereof. The lower end of each side wall 22 is provided with an outwardly laterally extending flange 30 which is disposed adjacent to and in contact with the outer lower surface 18a of the door 14 when the assembly is installed. Extending from each side wall 22 is a resilient locking member 32 which enables the housing 20 to be releasably locked into the recess 12. The locking members 32 are integral to the side walls 22 and have a free end provided with an abutment surface 34.
A roller carrier 36 is mounted in the cavity 26 to be adjusted vertically with respect to the housing 20. The roller carrier 36 consists of a pair of opposing corresponding plates 38, each of which is disposed adjacent the inner side of a housing wall 22. A substantially U-shaped groove 40 is provided at the upper end of each plate 38, the groove 40 being open at the top. The lower end of each plate 38 is provided with a contoured portion 42, as best seen in FIG. 2, which defines an outwardly extending circular flange 44. The U-shaped grooves 40 and circular flanges 44 are vertically aligned with one another. Projections 46, defining cam followers, extend inwardly from plates 38 between the grooves 40 and the outwardly extending flanges 44.
A camming element 48 is mounted within the housing 20 between the upper ends of the opposing plates 38. The camming element 48 defines an integral axle 50 which extends outwardly from each side of the camming element 48, as best seen in FIG. 2. The ends of the axle 50 are positioned within the U-shaped grooves 40 defined in the plates 38 and each end is rotatably supported in an aperture 54 defined through the upper end of each wall 22 of the housing 20, such that the axle end lies flush with the outer surface of the wall 22.
The lower end of the camming element 48 includes a substantially arcuate slot 56, into which the cam followers 46 extend. The upper end of the camming element 48 defines a plurality of gear teeth 58. An adjustment stem 60 extends sideways from the upper end of the housing 20. The adjustment stem 60 is provided with a threaded portion 62 which is disposed within the housing 20 and is adapted to engage and cooperate with the gear teeth 58 on the camming element 48 to rotate the camming element 48 about its axle 50 to thereby raise or lower the roller carrier 36 with respect to the housing 20. A second portion 64 of the adjustment stem 60 extends laterally outwardly from the housing 20 and extends through an aperture 66 provided in the side of the door frame 14, such that the end 68 of the adjustment stem 60 lies generally flush with the outer surface of the door frame side 70. A slot 72 is provided in end 68 of the adjustment stem 60 to enable it to be easily rotated and adjusted from outside the door frame 14.
A roller 74, defining an integral hub 76, is rotatably supported between the contoured portions 42 at the lower ends of the roller carrier plates 38. The hub 76 extends outwardly from each side of the roller 74 and is generally cylindrically-shaped so that it is supported in the circular flanges 44, as seen in FIG. 2. The outer periphery of the roller 74 defines a substantially U-shaped groove 78 which fits over the rail 80 provided on the track 16 on which the door frame 14 slides.
The installation of the adjustable roller assembly is accomplished by inserting the housing 20 into the recess 12. Because of the diverging slant of the locking members 32, the upper portions of the locking members 32 contact the second shoulders 12b of the slot 12 and are biased inwardly toward the sides of the housing 20 as the roller assembly 10 is pushed upwardly through the slot 12 until the free ends of the locking members 32 pass therethrough. At that point, the locking members 32 spring outwardly trapping the flat surface 18a defined by the recess 18 between the locking members 32 and the flanges 30, such that the abutment surfaces 34 of the locking members 32 contact the upper surface 82 of surface 18a and the upper surfaces of the flanges 30 are disposed adjacent and in contact with the lower surface of the surface 18a. When the roller assembly 10 is thus inserted, the sides of the housing 20 contact the first shoulders 12a and prevent lateral movement of the assembly 10 within the slot 12. The end 68 of the adjustment stem 60 is positioned to extend through the aperture 66 in the side of the door frame. The free ends of the locking members 32 are positioned approximately half-way across the respective notches 19. No tools are necessary for installation. When it is desired to remove the roller assembly 10 from the slot 12, an implement or tool is inserted through the open portions of the notches 19 and is used to press the locking members 32 inwardly to effect removal.
The roller carrier 36, and consequently the roller 74, may be adjusted vertically with respect to the housing 20 and door frame 14 from the side edge of the door frame after installation. The end of a screwdriver or such is positioned in the slot 72 at the end 68 of the adjustment stem 60 and rotated one way or the other depending upon whether it is desired to raise or lower the roller carrier 36 and roller 74. When the adjustment stem 60 is rotated, the threaded portion 62 in engagement with the gear teeth 58 on the camming element 48 act to rotate the camming element 48 about its axis 50. As the camming element 48 rotates, it has a camming effect on the cam followers 46 trapped in the arcuate slot 56 thereby causing the cam followers 46 to be pushed downwardly or raised upwardly depending on the direction of rotation of the adjustment stem 60. Since the cam followers 46 are integral with the plates 38, the roller carrier 36 and roller 74 are moved vertically downwardly or upwardly, respectively. The roller assembly 10 may be adjusted to take up the slack between the door frame 14 and the track 16 or to tighten the fit therebetween by lowering the roller 74. Conversely, the roller assembly 10 may be adjusted to increase the slack or loosen the fit therebetween by raising the roller 74.
While the above description describes a roller assembly which is installed in the lower edge of a door, it is understood that the roller assembly may also be installed in the upper edge of a door.
Thus it has been shown that the present invention provides an easily adjustable roller assembly for sliding doors which may be installed without tools.
Various features of this invention have been particularly shown and described in connection with the illustrated embodiment of the invention. However, it must be understood that these particular arrangements merely illustrate and that the invention is to be given its fullest interpretation within the terms of the appended claims. | An adjustable roller assembly for sliding doors including a housing adapted to be snap-fit into a recess provided in the upper or lower surface of a door frame, the housing defining a cavity which is open at the lower end. A roller carrier is mounted in the housing cavity and is vertically adjustable with respect to the housing. The lower end of the roller carrier defines circular flanges in which is rotatably mounted a roller having an integral hub. A camming arrangement associated with the roller carrier is accessible for adjustment from the side of the door frame and is operable to adjust the vertical position of the roller carrier and roller to adjust the slack between the door and the track upon which the roller is adapted to ride. | 8 |
BACKGROUND OF THE INVENTION
This application is a continuation of U.S. Ser. No. 989,700, filed Dec. 14, 1992, now abandoned, which is a continuation of Ser. No. 692,925 filed Apr. 29, 1991, now abandoned.
The invention relates to a method of controlling a reactive sputtering process as used, for example, in coating technologies which employ cathode sputtering.
The reactive gases used include O 2 , N 2 , CH 4 , H 2 S and the like. The coating process produces the corresponding compounds: oxides, nitrides, carbides or sulfides which are applied onto the substrate as layers. This reactive sputtering process has proven well in the field of production engineering. It has the advantage, among others, of rendering the production of chemical compounds reproducible. An example is the use of such reactive sputtering processes for the manufacture of transparent conductive layers for liquid crystal displays (LCDs).
Known are direct voltage sputtering and high frequency sputtering as well as hybrids thereof. Also known is the sputtering with a bias voltage where the substrates are placed onto an electrically insulated substrate carrier which, as opposed to the cathode, has a small negative bias voltage.
Direct voltage sputtering is limited to the cathodes (targets) made of an electrically conductive material since the insulator of a non-conductive cathode interrupts the current.
High frequency sputtering is used for the sputtering of insulators. Here, the high frequency source serves to supply power to the electrodes of the sputtering system.
In the practice, the types of high performance sputtering systems used in corresponding processes are those where a magnetic field in front of the cathode enhances the probability of particles to collide and thus become ionized.
A high performance sputtering device of this kind is described, for example in German patent 24 17 288.
This publication shows a cathode sputtering apparatus with a high sputtering rate which comprises a cathode the surface of which holds the material to be sputtered and deposited on a substrate. Further, it has a magnet which is adjusted such that the magnetic flux lines emanating from the sputtering surface and returning thereto form a discharge zone which has the form of a closed loop. It also includes an anode disposed outside the paths of the sputtered material traveling from the sputtered surface toward the substrate.
This patent proposes that the cathode surface to be sputtered and facing the substrate to be coated be planar, that the substrate, in the vicinity of the discharge zone, can be moved above the planar sputtering surface and parallel thereto, and that the magnet system generating the magnetic field be disposed on the side of the cathode which faces away from the planar sputtering surface.
SUMMARY OF THE INVENTION
The actualization of the principle on which the present invention is based is not restricted to cathode sputtering as described above. The subject matter of the invention is universally usable wherever the regulation of reactive sputtering processes is important.
The present invention addresses itself to the following tasks:
The control of the reactive sputtering process is to be basically improved. More particularly, it is the purpose of the invention to ensure a more stable sputtering operation, i.e. operation must remain stable at or in the proximity of a working point on the physical characteristic curve.
The sputtering should be free of arcing. Further, a high sputtering rate should be maintained during the sputtering process.
Finally, the subject matter of the invention is to be universally usable, namely in the above-described direct-current sputtering process is (DC sputtering), in high-frequency sputtering (HF sputtering), in combined DC/HF sputtering, in sputtering at medium frequencies (in the kilohertz range) and in sputtering with or without bias.
The stated tasks are accomplished in accordance with the invention by adjusting and keeping constant or approximately constant the working point on the physical characteristic curve of cathode voltage or working current over the flow of reactive gas to the sputtering apparatus, as defined by the value of one of the two factors determining the electrical power drain of the reactive sputtering process, by metering the flow of the reactive gas, oxygen for example, fed into the processing chamber. The total sputtering power, P=IV, is kept constant by the power supply system.
In detail, the invention proposes that the working point of the sputtering system, as defined by the value of the operating voltage (discharge voltage), be adjusted and maintained constant or approximately constant by metering the supply of reactive gas, for example O 2 , to the process chamber.
Alternatively, provision can be made such that the working point of the sputtering system, as defined by the value of the working current, is selected and maintained constant or approximately constant by metering the supply of reactive gas, for example O 2 , to the process chamber.
Additionally, it is proposed that when reactive sputtering processes are employed wherein the sputtered layers comprise chemical compounds, such as Al 2 O 3 , SiO 2 for example, which have a secondary electron yield that is higher than that of the metallic components, e.g. Al, Si, of the chemical compounds, a regulating characteristic is applied in the metering of the reactive gas, which is characterized by a descending characteristic curve for the discharge voltage/reactive gas flow, i.e. a diminishing discharge voltage with an increasing reactive gas flow is established in the characteristic curve.
In the latter embodiment, it is alternatively possible that when reactive sputtering processes are employed wherein the sputtered layers comprise chemical compounds, Al 2 O 3 , SiO 2 for example, which have a secondary electron yield that is higher than that of the metallic components, e.g. Al, Si, of the chemical compounds, the metered addition of the reactive gas is regulated by a control characteristic distinguished by an ascending discharge current/reactive gas flow curve, i.e. an ascending discharge current with increasing reactive gas flow is established as the characteristic.
It is further part of the subject matter of the invention that when reactive sputtering processes are employed wherein the sputtered-on layers comprise chemical compounds, CrO, for example, which have a secondary electron yield that is lower than that of the metallic components, e.g. Cr, of the chemical compounds, the metered addition of the reactive gas is regulated by a control characteristic distinguished by an ascending discharge voltage/reactive gas flow curve, i.e. an ascending discharge voltage with increasing reactive gas flow is established as the characteristic curve.
Alternatively, it is possible that when reactive sputtering processes are employed wherein the sputtered layers comprise such chemical compounds as CrO, for example, which have a secondary electron yield that is lower than that of the metallic compounds, e.g. Cr, of the chemical compounds, the metered addition of the reactive gas is regulated by a control characteristic distinguished by a descending discharge current/reactive gas flow curve, i.e. a descending discharge current with an increasing reactive gas flow is established as the characteristic.
In detail, provision is made such that the cathode voltage is supplied to a control as a found value or an input signal, and that the control processes the input signal into an output signal which is fed as an adjusting magnitude to an actuator in the form of a control valve for the supply of reactive gas, this valve metering the supply of reactive gas.
Alternatively, it is proposed that the current level be supplied to a control as a found value or an input signal, and that the control process the input signal into an output signal which, as a is fed as an adjusting magnitude to an actuator in the form of a control valve for the supply of reactive gas, this valve metering the supply of reactive gas.
The invention further comprises an apparatus for the practice of the above method.
In particular, the invention proposes that a sputtering apparatus be provided comprising a control system (reactive gas control) and a control valve for the metering of the reactive gas, that a signal line be provided supplying the cathode voltage to the input of the control, and that the output of the control system be connected to the control valve via a line which supplies the adjusting magnitude obtained in the control to the control valve.
Alternatively, in another embodiment, it is possible to employ the cathode current instead of the cathode voltage.
The invention accomplishes the following advantages:
The sputtering is ensured at a stable working point or in the proximity thereof. Sputtering is free of arcing. A high sputtering rate is maintained during the sputtering process.
Additional details of the invention, the object, and the advantages gained can be understood from the following description of an embodiment of an apparatus for the practice of the method in accordance with the invention.
BRIEF DESCRIPTION OF THE DRAWING
The embodiment and the physical characteristic curves of a reactive sputtering process as well as the control procedures employed are explained with reference to three figures.
FIG. 1 is a diagrammatic representation of the apparatus.
FIG. 2 shows the discharge voltage in relation to the O 2 --flow in the form of a curve.
FIG. 3 shows the discharge current in relation to the O 2 --flow in the form of a curve.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The apparatus serves to produce layers on a non-represented substrate by means of reactive sputtering. In the present case, these layers consist of chemical compounds, for example Al 2 O 3 or SiO 2 . A metallic target made of Al or Si is used for the sputtering. The sputtering atmosphere consists of a gas mixture comprising Ar and, as a reactive gas, O 2 .
The apparatus comprises a control system in which a certain control characteristic is installed. This control system, with the aid of the control characteristic, processes the cathode voltage as an input signal to form a regulating magnitude available at the output of the control system. This regulating signal is supplied to an adjusting means in the form of a control valve for the reactive gas O 2 .
On the basis of the installed control characteristic the flow of O 2 is regulated in such a manner that the established discharge voltage (working voltage) remains constant.
In those sputtering processes where the substrates are coated with chemical compounds, e.g. Al 2 O 3 , SiO 2 , which have a secondary electron yield that is higher than that of the metallic components, e.g. Al, Si, a control characteristic is applied in the metering of the reactive gas which is a descending characteristic curve for the discharge voltage/reactive gas flow, i.e. the characteristic curve is established as a descending discharge voltage with an increasing reactive gas flow.
The inventive achievement consists in the fact that a principle of control has been found, whose teaching is contrary to what is indicated by the physical characteristics, "cathode voltage over oxygen flow" (see FIG. 2) and "current over oxygen flow" (see FIG. 3), and which nevertheless works in practice, whereas a control along the physical characteristics leads to the "abortion" of the sputtering process.
The core of the invention teaches that the desired stable working point of the sputtering process is controlled through the metered addition of the reaction gas.
FIGS. 2 and 3 are discussed further below. First the design of the sputtering apparatus will be described with reference to FIG. 1.
In FIG. 1, the process chamber is referenced as 1. Numeral 2 designates the cathode. The target bears numeral 3. Numeral 4 designates the energy supply. This can be a DC power supply or an HF transmitter (high frequency). Provision can also be made for an energy source comprising a DC power supply and an HF transmitter. Further, an MF trasnmitter (medium frequency) can also be provided.
Numeral 5 refers to a control system having an input 6 in which the control characteristic is installed as the guiding magnitude for output 7.
Numeral 8 designates an actuator of the control circuit in the form of a control valve. 9 references a flow meter for argon. 10 is the reference numeral for the gas mixer. Inside the process chamber 1, there is a lance 11 having outlets 12 for the gas mixture consisting of O 2 and Ar. Depending on the application requirements, the outlet openings are arranged in a gas shower or lance or in any other suitable arrangement. Vacuum line 14 serves to bring the process chamber to the necessary low operating pressure.
Numeral 36 references the supply line for the reactive gas O 2 . 37 is a line carrying the O 2 --flow, controlled by the control system, to the gas mixture.
Numeral 38 designates the argon supply line. 39 is the connecting line between flow meter 9 and gas mixer 10. 40 is the connecting line between gas mixer and gas shower or lance 11.
The substrate and the layer growing thereon, e.g. Al 2 O 3 , are omitted for reasons of simplicity since they are generally known.
During the sputtering process, an Ar/O 2 --atmosphere, hence a reactive atmosphere, prevails in the process chamber.
The power supply unit 4 feeds, among other things, the electric power P, which is the product of voltage V and current I and is necessary for the sputtering process, via line 13 to cathode 2. Further power lines which may be necessary are omitted for simplicity's sake and to keep the drawing clear. During the sputtering process, there is a plasma inside the process chamber; cf. in this respect numerous prior art publications.
Line 15 serves to supply the cathode voltage to input 6 of control 5 (reactive gas control). On the basis of the guiding magnitude (control characteristic) installed in the control, the signal available at input 6 is processed into a regulating magnitude which is made available at output 7 of the control. Line 16 serves to supply this regulating magnitude to the actuator (control valve) for the O 2 --flow. The flow of O 2 is hence metered according to the installed control characteristic.
The following explanations are provided for a general understanding the procedures and the sputtering process described below.
Oxides, for example Al 2 O 3 or SiO 2 , will form during the sputtering. Instead of Al 2 O 3 or SiO 2 other oxides or chemical compounds may be formed. On the one hand, the oxides form the coating growing on the substrate and, on the other hand, they blanket the target surface over a more or less large area during the sputtering process. The formation of this coating or blanket begins on the non-eroded areas of the target surface and grows, depending on the parameters, more or less into the eroded areas of the target surface.
It is assumed hereinafter that the chemical compound of the growing coating is Al 2 O 3 and the reactive gas used is O 2 .
Depending on the extent to which the target surface is covered with oxide, there will be a more or less high yield of secondary electrons. An increased supply of O 2 , will produce a larger covering of the target with Al 2 O 3 . The greater the blanketing of the target, the greater will be the yield of secondary electrons. A higher yield of secondary electrons means a greater discharge current I. If the power is kept constant, this is equivalent to a diminishing discharge voltage V since P const =IV.
Further details on the physical and chemical bases of the processes described here can be understood from technical literature.
The paradox, i.e., the contrast between the physical characteristic curves, on the one hand, and the installed control characteristics, on the other will be explained below with the aid of FIGS. 2 and 3. As mentioned earlier, the inventive step lies in defining these control characteristics contrary to the teaching of the physical characteristic curves.
FIG. 2 shows the physical characteristic curve 19 for "cathode voltage over O 2 flow." Numeral 20 is the working point, the desired point of control, on the curve, corresponding to desired voltage V D U desired , and 22 is the corresponding O 2 flow. Numeral 23 is a an actual point which is below the desired point. Numeral 24 designates a second actual point which is above the desired point. The two actual voltages V A1 and V A2 are associated with these two actual points. Although according to the physical characteristic curve for the discharge voltage/reactive gas flow in FIG. 2, there are slopes of opposite signs in the portions 42, distinguished by a dotted parallel accompanying line, and 43, identified by a broken parallel accompanying line, both relevant to the sputtering, only one control characteristic is used to regulate the process in both portions, namely the working portion 43 of the curve, where the working point of interest is located. Contrary to the physical characteristic it is necessary to regulate according to a control characteristic having a slope of opposite sign (an apparent contradiction to the rule). Since the voltage ultimately decreases with increasing O 2 flow, the overall slope of the curve is negative, whereas the slope of the working portion 43 is positive.
The following is a description of the control behavior for V smaller than V D :
1. The control compares V to V D and determines when V A1 has been reached.
2. In contradiction to what the physical characteristic curve, dictates the controller reduces the flow of O 2 . This results in the following:
a. the oxide layer on the target surface is reduced,
b. the yield of secondary electrons thus decreases, i.e. the current I is reduced,
since P constant =IV, the discharge voltage hence increases and, exceeding V D , reaches the value V A2 .
3. The determines that V A2 has been reached.
4. The controller increases the flow of O 2 .
5. The oxide blanket on the target surface grows.
6. The yield of secondary electrons increases and so does the current strength.
7. Since P constant =IV, the voltage decreases and approaches and/or reaches the value V D .
Conclusion: Controlling the flow of O 2 adjusts working point 20 and V D .
The physical characteristic curve "Current strength I with respect to O 2 --flow" is in FIG. 3 represented as curve 27.
The desired operating current I D and the value 41 for the flow of O 2 are associated with the working point 30. The actual point 31 is associated with the actual current I A1 and actual point 32 with actual current I A2 . The physical characteristic curve for the discharge current/reactive gas flow in FIG. 3 shows that characteristic portion 44 indicated by a parallel dotted secondary line and characteristic portion 45 indicated by a parallel broken secondary line have slopes of opposite signs. Yet the control of the sputtering process in both portions involves only one control characteristic for the control of the sputtering process, namely that of the working portion 45 of the curve where the relevant working point is located. The control, in contrast to the physical characteristic curve, must follow a control characteristic having a slope of opposite sign (seemingly a contradiction of the rule). Since the current ultimately increases with increasing O 2 flow, the overall slope of the curve is positive, whereas the slope of the working portion 45 is negative.
The following is a description of how the control works if I is less than I D .
1. The controller compares I to I D and determines when I A1 , has been reached.
2. Contrary to dictates the physical characteristic curve, dictates the controller increases the flow of O 2 which leads to the following:
a. the oxide blanket on the target surface continues to grow,
b. the yield of secondary electrons hence increases, i.e. the current I increases,
c. this leads to an increase of the discharge current since P const =IV and, exceeding I A2 , has been reached I -2 , reference numeral 35.
3. The controller I A2 to I desired and determines that I A2 has been reached.
4. The controller reduces the flow of O 2 .
5. The oxide blanket on the target surface is further reduced.
6. The yield of secondary electrons is further reduced and the current strength hence decreases.
7. The actual current approaches the desired the current strength and eventually reaches the desired current.
Conclusion: Controlling the flow of O 2 adjusts working point 30 and I desired .
When sputtering layers which are made of chemical compounds, e.g. CrO where the yield of secondary electrons is smaller than the secondary electron yield of the corresponding metallic components, e.g. Cr, the present invention proposes characteristic parameters for cathode voltage/reactive gas flow and cathode current/reactive gas flow which, due to their reversed yield of secondary electrons, have a correspondingly reversed configuration. This reversion refers to the control characteristics and control processes described further above in connection with FIGS. 2 and 3. Additional details of this control process are disclosed in the above claims 7 and 8 and in the introductory part of the description.
Parts List
1 process chamber
2 cathode
3 target
4 energy supply
5 controller
6 input
7 output
8 control valve
9 flowmeter
10 gas mixer
11 apparatus
12 opening
13 line
14 vacuum line
15 line
16 line
17 ordinate
18 abscissa
19 curve
20 working point
21 voltage
22 O 2 --flow, value
23 actual point
24 actual point
25 actual voltage, U act-1
26 actual voltage, U act-2
27 curve
28 ordinate
29 abscissa
30 working point
31 actual point
32 actual point
33 operating current
34 actual current, I act-1
35 actual current, I act-2
36 line
37 line
38 line
39 line
40 line
41 O 2 --flow, value
42 portion of characteristic curve
43 portion of characteristic curve
44 portion of characteristic curve
45 portion of characteristic curve | A method is proposed for controlling a reactive sputtering process wherein the working point on the physical characteristic curves, cathode voltage or working current intensity over reactive gas flow to the sputtering apparatus, defined by the value of one of the two factors determining the electrical power drain of the reactive sputtering process, is adjusted and maintained constant by metering the reactive gas, for example O 2 , to the process chamber. Further, the invention proposes a device for the practice of the method, wherein a sputtering apparatus is provided, comprising a controller 5 (reactive gas controller) and a control valve 8 for metering the reactive gas. Further, a signal line 15 is provided which carries the cathode voltage to the input of the controller in which the output of the controller is connected to the control valve via a line 16 which supplies the adjusting magnitude computed in the controller to the control valve. | 2 |
BRIEF SUMMARY OF THE INVENTION
This invention relates to an electric sieve to be used for spraying fine particles or powdered substance and, more particularly, to an electric sieve suited for use with cooking or baking.
In the cooking or baking art, it is often desirable, such as when making a cake, that fine particles or powdered substances such as sugar and wheat flour, be homogeneously mixed with water or other liquids. When mixing the wheat flour with water, if the wheat flour is directly dropped in the water from a small mouth of a bag thereof, or from a spoon having the wheat flour thereon, the wheat flour will partially lump, since the flour cannot homegenously contact the water. If the mixture is stirred enough to eliminate the flour lumps, the mixture becomes sticky and often spoils the taste of the cooked cake and such.
Accordingly, in order that the wheat flour may homogeneously be sprayed in the water without forming lumps thereof, it is desirable that the flour be sprayed by using a sieve and be rapidly mixed with the water. To spray the flour by using a sieve, manually, a cook has to shake the sieve with one hand, and rapidly mix the sprayed powder material with the water by using a stirrer with his other hand in a stirring motion. However, this operation of different movements of both hands at the same time, can be quite difficult, especially for a housewife.
Accordingly, an object of the present invention is to provide an electric sieve which can easily be held and operated by one hand of a housewife and can homogeneously spray fine particles or powdered substance therefrom.
Another object of the present invention is to provide an electric sieve which is compact, simple in structure and reliable in its operation.
Other objects and features of the present invention will become apparent from the following detailed description of specific embodiments thereof.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing an electric sieve according to one embodiment of the present invention;
FIG. 2 is a vertical sectional view of the electric sieve shown in FIG. 1;
FIG. 3 is a bottom view of the electric sieve shown in FIG. 1;
FIG. 4 is a perspective view showing the motor cover with which the electric sieve of FIG. 1 is equipped.
FIG. 5 is a bottom view showing an electric sieve according to a second embodiment of the present invention;
FIG. 6 is a vertical sectional view showing an electric sieve according to a third embodiment of the present invention, and
FIG. 7 is a vertical sectional view, partly in elevation, showing an electric sieve according to a fourth embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the first embodiment shown in FIGS. 1 to 4, there is provided a generally cylindrical casing 1 at the outer side of which a handle 2 is integrally formed from a synthetic resin. The handle 2 has a relatively thin flat portion 2a extending horizontally from the outer surface of the casing 1 near the upper end thereof, and a cylindrical hollow portion 2b extending vertically from the outer end of the flat portion 2a, thereby leaving a vertical space 3 between the outer surface of the casing 1 and the cylindrical portion 2b of the handle 2 to allow easy holding of the handle. A battery 4 is provided in the cylindrical hollow portion 2b of the handle, and a switch button 5 projects above the portion 2b, adapted to complete an electrical circuit and cause an electric current to flow to a motor (referred to hereinafter) through a conductive plate 6 and lead wires 7 by operation thereof.
Extended inwardly from the inner surface of the wall of the casing 1 near the lower part thereof are three arms 8 for supporting a small housing 9 substantially at the center of the casing. These arms 8 are spaced at substantially the same angular intervals and one of the arms 8a is located directly below the inner end of the flat handle portion 2a. These arms 8 and 8a and the small central housing 9 are also integrally formed with the casing 1 from the synthetic resin.
A cylindrical motor cover 10 is disposed within the small central housing 9 providing a small annular space between the inner peripheral wall of the housing and the outer peripheral wall of the motor cover 10. The motor cover 10 has, as shown in FIG. 4, an integral plate-like upper bridge portion 10a extending across the upper rim of the cylindrical motor cover 10 and is connected to the housing 9 by a screw 11 threaded through the upper end of the bridge portion 10a into the inner upper wall of the housing 9.
An electric motor 12 is snugly received and secured within the motor cover 10 and has an output shaft 13 extended downwardly through a center opening 14a of a meshed member 14 such as a wire net.
The meshed member 14 is firmly connected to the motor cover 10 by screws 15 passing through an imperforate annular portion 14b of the meshed member 14. The peripheral edge of the meshed member 14 is slightly spaced from the inner peripheral wall of the annular sleeve portion 1a at the lower end of the casing 1 but extending radially beyond an annular flange or shoulder 1b provided at the upper end of the sleeve 1a, thereby allowing the meshed member 14 to vibrate inside of the sleeve 1a below the flange or shoulder 1b.
A disc-shaped weight member 16 is eccentrically connected to the output shaft 13 of the motor below the meshed member 14.
The motor 12 is electrically connected to the battery 4 in the handle 2 by lead wires 7 which pass through a hole in the motor cover 10 and the supporting arm 8a and along the outer surface of the casing 1 and reach to the conductive plate 6 in the flat handle portion 2a.
When one intends to spray the fine particles or powdered substance by the present electric sieve, the sieve is lifted by holding the handle 2 and carried to a desired place where the powdered substance is to be sprayed. Then, after supplying the powdered substance in the casing 1, the switch button 5 is pressed down to complete the circuit and cause electric current to flow from the battery to the motor 12. As is apparent from the disclosure set forth above, when the motor 12 is actuated, the eccentric disc 16 rotates by the rotation of the output shaft 13, so that the motor cover 10 secured to the motor vibrates in the space inside of the housing 9. Thus, the meshed member 14 connected to the motor cover 10 also vibrates, thereby homogeneously spraying the powdered substance through and below the meshed member 14. The vibration of the meshed member 14 stops instantaneously when the pushing force on the switch button is released.
Though the disc-shaped weight member 16 is eccentrically connected to the output shaft 13 of the motor 12 in the first embodiment, a bar-shaped weight member 17 may be used in place of the disc-shaped weight member by connecting one end thereof to the output shaft 13 of the motor 12 as shown in the second embodiment of FIG. 5.
Another modification of the present invention will be described with reference to a third embodiment shown in FIG. 6. In this embodiment the disc-shaped weight member 16, which is connected to the output shaft 13 of the motor 12, is disposed in the motor cover 10' above the meshed member 14'. The lower open end of the motor cover 10' is closed by a closure member 18 fixed thereto by screws 19. The closure member 18 has a central threaded extension 18a extending downwardly through the central opening 14'a in the meshed member 14'. The meshed member 14' is secured to the closure member 18 by a cap nut 20 threadedly engaging the extension 18a against the imperforate annular portion 14'b of the meshed member 14'. The meshed member 14' has an annular vertical flange 14'c around the periphery thereof, which is partially received within an annular recess defined by the outer sleeve 1a and the sleeve 1c at the lower end portion of the casing 1 and spaced from both of the sleeves 1 a and 1c to allow the vibration of the meshed member 14'. In place of the push-type switch 5 in the first embodiment, a slide switch 21 is provided in the flat handle portion 2a, and the lead wires 7 running along the outer wall of the casing 1 are covered by a wire cover 22. Other remaining features of this embodiment are substantially the same as those of the first embodiment except design features.
A further modification of the present invention will be described with reference to the fourth embodiment shown in FIG. 7. In this embodiment, only one arm 8"a is integrally formed with the casing 1 and terminates at the center ring portion 9" to which the motor cover 10" is connected by the screw 11. Different from the housing 9 or 9' in the previous embodiments, the center ring portion 9" of this embodiment does not substantially enclose the motor cover 10". The meshed member 14" is integrally formed with a closure member 18' which is welded to the lower free end of the motor cover 10". The upper surface of the center ring portion 9" is covered by a cap 23. The other remaining features are substantially the same as those of the third embodiment shown in FIG. 6.
The electric sieve according to the present invention is so constructed that fine particles or a powdered substance can be sprayed very easily only by holding the handle portion 2 thereof and operating the switch button 5 or 21. Further, it is very light in weight and cheap to manufacture when the casing 1, handle portion 2, arms 8 or 8"a and central housing 9 or ring portion 9" are all integrally formed from synthetic resin. Moreover, since the vibratory movement of the meshed member is attained by the weight member 16 or 17 eccentrically attached to the output shaft 13 of the motor 12 secured within the motor cover 10, which is vibratable with respect to the supporting arm member to which the meshed member 14 is connected, it is very simple in structure and reliable in operation. Further, it is very easy to exchange the meshed member for another one of different mesh size.
Although the present invention has been described with reference to the preferred embodiments thereof, modifications and alterations may be made without departing from the spirit of the present invention. | A casing, in which a powdered substance to be sieved is fed, is provided with a handle portion containing a battery therein. A supporting arm extends from the inner wall of the casing and is connected with a vibratable motor cover at the center portion of the casing. A motor is mounted within the motor cover, and a weighted member is eccentrically connected to the output shaft thereof. The meshed member of the sieve is connected to the motor cover. | 8 |
BACKGROUND
The present invention relates to testing wireless radio frequency (RF) data signal transmitters, and in particular, to facilitating comparison of RF data signals transmitted by a device under test (DUT) and received by a test system.
Many communication devices use wireless technologies both for connectivity and for communications purposes. Because wireless devices transmit and receive electromagnetic waves, and because two or more wireless devices have the potential of interfering with the operations of one another by virtue of their signal frequencies and power spectral densities, these devices and their wireless technologies subscribe to various wireless-technology standard specifications.
In the designing of such devices, engineers take extraordinary care to ensure that such devices will meet or exceed each included wireless technology's prescribed standard-based specifications. Furthermore, once these devices are being mass produced, they are tested to ensure that manufacturing defects will not cause improper operation, including their adherence to the included wireless technology standard-based specifications.
As part of such manufacturing testing, current wireless device test systems employ a subsystem for analyzing signals received from a device under test (DUT), e.g., a subsystem such as a vector signal analyzer (VSA) for analyzing signals received from the DUT, and a subsystem such as a vector signal generator (VSG) for generating signals to be received by the DUT. The analysis performed by a VSA and the signals generated by a VSG are usually programmable so as to allow each to be used for testing a variety of wireless technology standards with differing frequency ranges, bandwidths, and modulation characteristics.
Today's wireless devices typically include circuitry designed to operate in accordance with several wireless signal technologies, such as WiFi (e.g., 802.11x), Bluetooth, cellular radio access technologies (e.g., LTE), and the like. In addition, to keep test time and costs from increasing as more and more wireless signal technologies are incorporated in such devices, some of today's wireless signal test systems are designed to capture and analyze longer signal sequences that have physical characteristics prescribed by two or more wireless signal technology standards.
In testing longer sequences of multiple technology characteristics, the test programs that control the test system (e.g., by controlling the VSA, VSG and other subsystems) become longer and more complex, and as does the test program debugging process. Often program debugging requires attaching external instruments, such as multi-channel oscilloscopes, to the test system and associated other test instruments in order to examine various control signals and power-versus-time displays so as to understand and solve problems related to the new-program debugging process.
SUMMARY
In accordance with the presently claimed invention, a system and method are provided for facilitating comparison of radio frequency (RF) data signals transmitted by a device under test (DUT) and received by a test system. A RF data signal received from a DUT is analyzed to provide analysis data indicative of conformance of the DUT operation with one or more applicable signal standards. The RF data signal is also converted to related conversion data that can be stored with state machine data corresponding to states of the signal testing subsystem. This state machine data can then be processed as needed with the analysis data and conversion data for off-line tasks such as debugging new test programs and procedures.
In accordance with one embodiment of the presently claimed invention, a test system for facilitating comparison of radio frequency (RF) data signals transmitted by a device under test (DUT) and received by the test system includes:
signal routing circuitry for routing at least one RF transmit data signal to and at least one RF receive data signal from a DUT;
data signal source circuitry coupled to the signal routing circuitry and responsive to a portion of a plurality of control signals and a plurality of transmit data by providing the at least one RF transmit data signal and a portion of a plurality of system data;
data signal analysis circuitry coupled to the signal routing circuitry and responsive to another portion of the plurality of control signals by processing the at least one RF receive data signal and providing a plurality of signal analysis data and another portion of the plurality of system data;
signal conversion circuitry coupled to the signal routing circuitry and responsive to the at least one RF receive data signal by providing a related plurality of receive conversion data; and
a state machine coupled to the data signal source circuitry and the data signal analysis circuitry, and responsive to the plurality of system data by providing a plurality of state machine data.
In accordance with another embodiment of the presently claimed invention, a method of facilitating comparison of radio frequency (RF) data signals transmitted by a device under test (DUT) and received by a test system includes:
routing at least one RF transmit data signal to and at least one RF receive data signal from a DUT;
receiving a portion of a plurality of control signals and a plurality of transmit data and in responsive thereto providing the at least one RF transmit data signal and a portion of a plurality of system data;
receiving another portion of the plurality of control signals and in responsive thereto processing the at least one RF receive data signal and providing a plurality of signal analysis data and another portion of the plurality of system data;
converting the at least one RF receive data signal to provide a related plurality of receive conversion data; and
processing the plurality of system data with a state machine to provide a plurality of state machine data.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a conventional testing environment for testing a wireless signal device under test (DUT).
FIG. 2 depicts intended and actual transmit signals from the DUT for the testing environment of FIG. 1 .
FIG. 3 is a functional block diagram of a conventional testing environment for testing a wireless signal DUT with the addition of external commercial test equipment for capturing the signal directly from the DUT.
FIG. 4 depicts intended and actual transmit signals from the DUT along with corresponding capture control signals within the tester for the testing environment of FIG. 3 .
FIG. 5 is a functional block diagram of a wireless signal testing environment using a test system and supporting one or more test methods in accordance with exemplary embodiments of the presently claimed invention.
FIG. 6 is functional block diagram of the testing environment of FIG. 5 with the test system supporting one or more test methods in accordance with further exemplary embodiments of the presently claimed invention.
FIG. 7 is a functional block diagram of a testing environment using a test system and supporting one or more test methods in accordance with further exemplary embodiments of the presently claimed invention.
DETAILED DESCRIPTION
The following detailed description is of example embodiments of the presently claimed invention with references to the accompanying drawings. Such description is intended to be illustrative and not limiting with respect to the scope of the present invention. Such embodiments are described in sufficient detail to enable one of ordinary skill in the art to practice the subject invention, and it will be understood that other embodiments may be practiced with some variations without departing from the spirit or scope of the subject invention.
Throughout the present disclosure, absent a clear indication to the contrary from the context, it will be understood that individual circuit elements as described may be singular or plural in number. For example, the terms “circuit” and “circuitry” may include either a single component or a plurality of components, which are either active and/or passive and are connected or otherwise coupled together (e.g., as one or more integrated circuit chips) to provide the described function. Additionally, the term “signal” may refer to one or more currents, one or more voltages, or a data signal. Within the drawings, like or related elements will have like or related alpha, numeric or alphanumeric designators. Further, while the present invention has been discussed in the context of implementations using discrete electronic circuitry (preferably in the form of one or more integrated circuit chips), the functions of any part of such circuitry may alternatively be implemented using one or more appropriately programmed processors, depending upon the signal frequencies or data rates to be processed. Moreover, to the extent that the figures illustrate diagrams of the functional blocks of various embodiments, the functional blocks are not necessarily indicative of the division between hardware circuitry. Thus, for example, one or more of the functional blocks (e.g., processors, memories, etc.) may be implemented in a single piece of hardware (e.g., a general purpose signal processor, random access memory, hard disk drive, etc.). Similarly, any programs described may be standalone programs, may be incorporated as subroutines in an operating system, may be functions in an installed software package, etc.
As discussed in more detail below, a system and method are introduced for adding and using additional subsystems, internal to a testing system, which will support program debug for virtually any and all test programs, particularly those that involve long multi-technology signal sequences. As such, overall costs are reduced by eliminating need for costly external testing adjuncts and by potentially shortening program debug time by providing insights unavailable when using external testing adjuncts. Furthermore, it allows one to visualize what is actually happening between the DUT and test system in the sense that the DUT and test system are controlled independently so that the sequences, while appearing to be highly coordinated, are more loosely coupled. Having a view of what's happening within the DUT and tester offers a more complete debugging picture. Also, this can be achieved without imposing a test-time penalty. During normal operations, it is a matter of simply keeping a record, in parallel with ongoing execution of the test program. In the event of an error, the signal and control capture signal data can then be used to diagnose what has occurred.
Referring to FIG. 1 , a conventional testing environment includes a test system 100 , or tester, for testing a wireless signal DUT 10 . The DUT 10 includes, among other subsystems, a RF transceiver 12 and a set 14 of pre-defined signal sequences to be initiated by one or more firmware routines, software commands or hardwired circuit structure(s) (various forms of each of which are well known in the art). The DUT 10 transmits a test signal sequence 13 t over a signal communication medium 14 (which is typically a hardwired signal path for purposes of testing, but may also be a wireless signal connection if desired) for reception by the tester 100 .
The tester 100 includes, among other subsystems, signal routing circuitry 112 (discussed in more detail below), signal analysis circuitry 114 (e.g., a VSA), test signal generating circuitry 116 (e.g., a VSG), data storage circuitry 118 (e.g., memory circuitry locally within the tester 100 or remotely available via a network) and control circuitry 120 (e.g., microprocessor- or microcontroller-based). The control circuitry 120 exchanges control signals in data 121 a , 121 g with the VSA 114 and VSG 116 , and provides control signals 121 s , as needed, for the signal routing circuitry 112 . The control circuitry 120 can also exchange control signals and data 121 c with external circuitry, such as an external controller in the form of a personal computer (not shown).
The signal routing circuitry 112 , in accordance with its control signals 121 s as required, performs two basic functions: routing the DUT transmit signal 13 t as the input signal 115 to the VSA 114 , and routing the VSG output signal 117 to the DUT as a DUT receive signal. The routing circuitry 112 can be a switch, such as a single-pole 124 , double-throw 126 a , 126 g switch in which the signal path 122 switches between receive and transmit modes of the tester 100 (and transmit and receive modes of the DUT, respectively). Alternatively, the signal routing circuitry 112 can be implemented in other known ways (e.g., as a diplexer).
As depicted in FIG. 1 , in accordance with the pre-defined signal sequence 14 , the DUT transceiver 12 transmits a signal 13 t having, for example, three sub-sequences of which the middle sequence has a significantly reduced signal level or power. This signal 13 t , routed as the input signal 115 to the VSA 114 , results in a captured signal 119 aa which is sampled and provided by the VSA 114 as digitized signal data 119 a for storage in the memory 118 . As depicted in FIG. 1 , the captured signal 119 aa is lacking the middle sequence having significantly reduced signal power.
Referring to FIG. 2 , this can be better visualized. As depicted in the upper signal wave form diagram, the intended DUT transmit signal 13 i was to include a middle sequence having increased signal power. As a result, all three signal sub-sequences A, B, C would have signal power sufficient to exceed the trigger level within the VSA 114 and thereby be assured of being captured all signal sub-sequences A, B, C.
However, as depicted in the lower signal diagram, the actual DUT transmit signal 13 t erroneously included a middle sequence B having significantly reduced signal power insufficient to exceed the trigger level, and, therefore, prevented from being captured by the VSA 114 as part of the captured test signal 119 aa . Accordingly, subsequent analysis of the captured data signal 119 aa could erroneously conclude that the second sub-sequence captured corresponds to the intended second sub-sequence B when, in fact, it corresponds to the third sub-sequence C. As a result, the test program would result in an erroneous analysis, and without any other data describing or somehow otherwise related to the actual received signal 13 t , detection and/or correction of this erroneous analysis would be difficult and de-bugging of the test program would require significantly more time.
Referring to FIG. 3 , one approach that has been used in an attempt to capture information about the actual DUT signal 13 t includes the use of an external triggered instrument 132 , such as a triggering oscilloscope, which can sample and store signal data 133 corresponding to the actual DUT signal 13 t . High resolution data is not required, and lower resolution signal data 133 will be adequate and can be stored using less memory 134 . This power-versus-time (PVT) data envelope 133 corresponding to the actual DUT signal 13 t can be stored and later compared, e.g., in terms of timing of the signal peaks and valleys, among other characteristics, as part of any troubleshooting or debugging of a test program.
Referring to FIG. 4 , as before, the intended DUT signal 13 i includes sub-sequences with the middle sub-sequence having increased signal power. However, the actual DUT signal 13 t includes sub-sequences in which the middle sub-sequence erroneously has lower signal power. As a result, the signal profiles for the capture control signal associated with the intended DUT signal 13 i will differ from that of the capture control signal profile as generated within the VSA 114 for the actual DUT signal 13 t . Such difference in capture control signal profiles, e.g., differences in capture control signal pulses versus time, provide insight into possible causes of the program error. However, the capture control signal generated by the VSA 114 is not accessible to the external instrumentation 132 . Accordingly, one or more additional external sub-systems would be required to collect, compare and/or correlate the capture control signals produced by the VSA 114 and external instrumentation 132 .
Referring to FIG. 5 , in accordance with exemplary embodiments of the presently claimed invention, the tester 200 further includes a sub-system 202 for capturing signal data related to the actual DUT signal 13 t . Also, the signal routing circuitry 112 a has the additional ability to provide a signal 203 corresponding to the actual DUT signal 13 t . For example, when implemented as a single-pole, double-throw switch, the pole 124 a can include a power divider so that the VSA input signal 115 and the diverted input signal 203 both correspond to the actual DUT signal 13 t.
This sub-system 202 includes a power detector 204 , analog-to-digital conversion (ADC) circuitry 206 , digital data storage circuitry 208 (e.g., memory circuitry) and a state machine 220 , interconnected substantially as shown. The power detector 204 detects the signal power envelope of the incoming signal 203 . The detected power envelope signal 205 is converted to a digital signal 207 by the ADC circuitry 206 . This digital data 207 is stored in the memory 208 in accordance with one or more control signals 221 s from the state machine 220 . The state machine 220 also receives the VSA 121 a and VSG 121 g control signals and data, as well as control and/or data signals 221 a , 221 g providing information about the sub-system states of the VSA 114 and VSG 116 . Such sub-system control information and data can also be stored in the memory 208 in accordance with the state machine control signals 221 s . As a result, one or more state machine data signals 209 can be provided, e.g., depicting the signal power envelope 209 a of the incoming DUT signal 203 and the capture control signals 209 b.
This advantageously provides for capture and later access to a PVT record of signal sub-sequences A, B, C ( FIGS. 2 and 4 ), plus state machine data (e.g., capture control signal data) associated with the capture of the incoming DUT signal 203 . Since the power detector 204 measures the power envelope of the signal, fewer data bits are required and a lower sampling rate can be used, thereby minimizing the amount of capture memory needed. The system state machine 220 will reflect internal timing in controlling the capture and storage in the memory 208 . As a result, internal timing, which would not otherwise be accessible by external instruments ( FIG. 3 ), can be used to cross-reference, compare and/or correlate the captured PVT data against internal timing markers. For example, the state machine states 209 b during the writing of the data 207 into memory 208 can be stored in the memory 208 along with the PVT envelope data 209 a . This provides a more richly populated set of troubleshooting information for use when debugging new or modified test programs.
Referring to FIG. 6 , in accordance with further exemplary embodiments of the presently claimed invention, such a tester 200 can also be used for troubleshooting and debugging test programs during performance of receive signal tests of the DUT 10 , i.e., where the VSG 116 is providing a test signal 117 to be routed out to the DUT 10 via the test signal path 14 as a receive signal 13 r for the DUT 10 . In this testing scenario, the power detector 204 and ADC circuitry 206 may or may not be needed. However, the state machine 220 can continue to provide state data 209 a , 209 b for storage in the memory 208 . This data 209 can later be accessed when needed for troubleshooting or debugging a test program.
Additionally, in DUT testing scenarios where frequency division duplex (FDD) signals are used, the VSA 114 and VSG 116 can both be active, with the VSA input signal 115 being received and processed by the VSA 114 while the VSG 116 is providing its output signal 117 . Test systems and methods in accordance with exemplary embodiments of the presently claimed invention allow for inspection of data packets received by the VSA 114 , e.g., to identify an erroneous synchronization event.
Referring to FIG. 7 , in accordance with further exemplary embodiments of the presently claimed invention, the test system 300 can be implemented to support testing of multiple DUTs 10 a , 10 b , 10 c , 10 d . (This illustrative example involves a testing environment for four DUTs, but as will be readily appreciated by one of ordinary skill in the art, this implementation can be scaled down or up to support testing of smaller or larger numbers of DUTs). In this exemplary embodiment, the tester 300 includes corresponding numbers of routing circuits 12 aa 12 ab , 12 ac , 12 ad , power detectors 204 a , 204 b , 204 c , 204 d , ADC circuits 206 a , 206 b , 206 c , 206 d and memory elements 208 a , 208 b , 208 c , 208 d (as will be readily appreciated, however, a single memory element can also be used to provide sufficient memory for storing the converted data 207 a , 297 b , 207 c , 207 d ). The tester 300 also includes a multiplexor 302 and a signal splitter 304 .
The DUT signals 13 ta , 13 tb , 13 tc , 13 td from the DUT transceivers 12 a , 12 b , 12 c , 12 d are routed by the signal routing circuits 112 aa , 112 ab , 112 ac , 112 ad to the multiplexor 302 , which, in accordance with one or more control signals 121 m from the controller 120 , selects one of its input signals 115 a , 115 b , 115 c , 115 d to be provided 115 to the VSA 114 , e.g., during successive time intervals t1, t2, t3, t4. As can be seen, the state machine subsystem 202 ( FIG. 5 ) is replicated in accordance with the number of the DUTs 10 to be tested. This allows the PVT envelope data of each diverted DUT signal 203 a , 203 b , 203 c , 203 d to be sampled and stored, as discussed above.
In this example, the third DUT 10 c is providing an erroneous signal 13 tc , which, unlike the remaining DUT signals 13 ta , 13 tb , 13 td , includes a signal sub-sequence with significantly reduced signal magnitude, as opposed to the intended significantly increased signal magnitude (e.g., corresponding to sub-sequence B as depicted in FIGS. 2 and 4 ). This signal 13 tc is routed by the multiplexor 302 , e.g., during time interval t3, to the VSA 114 . This results in the capture and storing of an incomplete signal sequence 119 aa 3 , similar to those as described above. Meanwhile, the state machine subsystem associated with the third DUT 10 c produces PVT data 209 ca and control signal 209 cb to be made available as data 209 c retrievable from the memory 208 c for analysis in determining problems with the test program.
Alternatively, for DUT receive system testing, the VSG output signal 117 is distributed by the splitter 304 and routing circuits 112 aa , 112 ab , 112 ac , 112 ad to the DUTs 10 a , 10 b , 10 c , 10 d . As discussed above, the VSA 121 a and VSG 121 g control signals and other VSA and VSG state data 221 a , 221 g are captured by the state machine 220 and stored 221 s in the memory 208 a , 208 b , 208 c , 208 d , for later use in correlating signal emissions from the VSG 116 with internal system control states.
As will be further appreciated, in accordance with this implementation 300 , one DUT signal is monitored by the VSA 114 during any given time interval. However, advantageously, all DUT signals can nonetheless be monitored by having their respective PVT envelopes sampled and stored along with state machine information for later analysis and use in program debugging.
Various other modifications and alterations in the structure and method of operation of this invention will be apparent to those skilled in the art without departing from the scope and the 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. It is intended that the following claims define the scope of the present invention and that structures and methods within the scope of these claims and their equivalents be covered thereby. | A system and method for facilitating comparison of radio frequency (RF) data signals transmitted by a device under test (DUT) and received by a test system. A RF data signal received from a DUT is analyzed to provide analysis data indicative of conformance of the DUT operation with one or more applicable signal standards. The RF data signal is also converted to related conversion data that can be stored with state machine data corresponding to states of the signal testing subsystem. This state machine data can then be processed as needed with the analysis data and conversion data for off-line tasks such as debugging new test programs and procedures. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention disclosed and claimed herein generally pertains to an apparatus and method that uses a passive or active sensor, such as a low-cost RF Identification (RFID) tag, to determine that a specified object is not in a correct or proper orientation. More particularly, the invention pertains to apparatus of the above type for use with shipping containers and the like, to readily determine that a container is not in a “right-side-up” orientation. It is anticipated that embodiments of the invention will be useful for detecting improper container orientation in warehouses or other environments in which it is difficult or time consuming to visually inspect the orientations of individual containers.
[0003] 2. Description of the Related Art
[0004] As is well known, conventional cartons or containers, of a type widely used to pack, ship and store products of many different kinds, typically have six rectangular sides. Each of the sides is in substantially orthogonal relationship with every other side with which it shares a common edge. As is further well known, it is very common to designate one of the sides of such containers as the top side, and the opposing side as the bottom side. Moreover, it may be important to maintain the container in a “right-side-up” orientation. In such orientation, the top side of the container is directed upward, and the bottom side is conversely directed downward. This may be necessary to prevent damage or to ensure safety. For example, a container may be used to hold comparatively fragile products, such as computer equipment or other electronic components. To protect the product if the container is unintentionally dropped, substantial cushioning material could be placed between the product and the bottom side of the container. However, if the container is not kept in a right-side-up orientation, the benefit of the cushioning placed along its bottom side would be substantially reduced.
[0005] Notwithstanding the importance of proper orientation, it may frequently be quite difficult to determine whether a box or container, as it is being stored or shipped, is in fact correctly oriented. This situation is often encountered in high volume package environments, such as warehouses, manufacturing facilities and transport vehicles. In these types of environments, it may be difficult or impossible to visually inspect every side of a container, or to detect orientation markings printed thereon. Accordingly, it would be beneficial to provide container handlers and others with improved non-visual means for readily detecting improper orientation of containers or boxes.
BRIEF SUMMARY OF THE INVENTION
[0006] The invention provides an apparatus and method for using low cost, RF sensor technology, such as RFID tags or devices, to determine whether or not containers or other objects are in a right-side-up orientation. In a useful embodiment, a standard passive RFID tag is affixed to a disk contained in a flat structure. The disk is directed into a shielded region, when an attached box or container is oriented properly. When the box or container is in any other orientation orthogonal to the proper orientation, the disk becomes unshielded. This allows a signal to be received from the RFID tag, to indicate that the box is not properly oriented. A further embodiment of the invention is directed to sensor apparatus for use in detecting an improper orientation of a container or other object with respect to a substantially horizontal surface. The apparatus includes a structure having sides in spaced apart relationship, to define an enclosed space within the structure. Selected shielding material attached to the structure shields a specified region of the enclosed space against RF signals, the shielded region being located in the lowest portion of the enclosed space when the structure is in a reference orientation with respect to the horizontal surface. An RF sensor device is positioned in the enclosed space, the RF sensor device being sized to move freely within the space. A guide element mounted in the space guides the RF sensor device in moving between a shielded region and an unshielded region of the space, when the structure is correspondingly moved between its reference orientation and an improper orientation corresponding to an improper orientation of the object.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0007] The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
[0008] FIG. 1 is a perspective view showing orientation sensors constructed in accordance with the invention.
[0009] FIGS. 2-5 are views respectively showing an orientation sensor of FIG. 1 in different positions, to illustrate the operation thereof.
[0010] FIG. 6 is a sectional view taken along line 6 - 6 of FIG. 2 .
[0011] FIG. 7 is a sectional view taken along line 7 - 7 of FIG. 4 .
DETAILED DESCRIPTION OF THE INVENTION
[0012] Referring to FIG. 1 , there is shown a conventional six-sided shipping container, carton or box 100 , supported upon a substantially horizontal support surface 102 . More particularly, container 100 comprises six rectangular-shaped sides or panels 100 A- 100 F, wherein each side is in substantially orthogonal relationship with each adjacent side, that is, with each side with which it has a common edge. Side 100 A is the top side of container 100 , and side 100 B is the bottom side thereof. Thus, all the force received from surface 102 to support container 100 is received through bottom side 100 B. FIG. 1 further shows sides 100 C- 100 F respectively extending between top side 100 A and bottom side 100 B. Bottom side 100 B shares common edges with each of the sides 100 C- 100 F, and is thus respectively adjacent thereto.
[0013] Horizontal support surface 102 may comprise, for example, a floor or a load carrying shelf in a warehouse, or the bed of a truck provided to transport container 100 . Surface 102 may also be the top sides of one or more other containers that container 100 has been stacked upon. Regardless of the nature of horizontal surface 102 , it will frequently be very important to place and maintain container 100 on surface 102 so that container 100 is right side up. In such orientation, top side 100 A is the uppermost side of container 100 , and bottom side 100 B is in contact with horizontal surface 102 . This is the orientation shown in FIG. 1 .
[0014] Referring further to FIG. 1 , there are shown orientation sensors 106 and 108 , each comprising an embodiment of the invention, respectively attached to adjacent sides 100 C and 100 F of container 100 . Sensors 106 and 108 are shown attached to the outside of container 100 , to avoid interfering with any product or items (not shown) that may be placed within container 100 . Alternatively, one or both of the orientation sensors could be attached to their respective sides within container 100 , to protect the sensors when container 100 is being handled. This mode of attachment would also prevent tampering with sensors 106 and 108 .
[0015] FIG. 1 shows orientation sensor 106 comprising a comparatively flat chamber or other structure 110 , that contains a narrow enclosed space 112 . A disk 114 , formed of plastic or other suitable material that will readily occur to those of skill in the art, is placed within the space 112 . Disk 114 serves as a holder or carrier for an RFID tag 116 that is encased or embedded in the disk 114 . Disk 114 is sized to provide clearance between the sides of disk 114 and surfaces of structure 110 that serve to define boundaries of space 112 . By providing such clearance, disk 114 and its RFID tag 116 are able to move freely within enclosed space 112 .
[0016] FIG. 1 further shows two linear members 118 and 120 contained in space 112 of structure 110 , the two members being joined together to form a “V” configuration. The linear members 118 and 120 are shown to incline downwardly toward the bottom of space 112 , as viewed in FIG. 1 . Thus, the “V” formed by linear members 118 and 120 serves as a guide element for disk 114 , to guide the disk to the lower portion of space 112 when structure 110 is oriented as shown in FIG. 1 . This orientation is referred to herein as the reference orientation of structure 110 . Disk 114 , when positioned between the two linear members near the point of the “V” formed thereby, is referred to herein as being in its home position.
[0017] FIG. 1 further shows metal foil or other RF shielding material attached to structure 110 , to define a shielded region 122 of enclosed space 112 . Dimensions of the shielded region 122 are selected to ensure that disk 114 and RFID tag 116 are entirely within the shielded region 122 , whenever disk 114 is in its home position. Thus, whenever RFID tag 116 is in such position, it is prevented by the shielding material from either detecting or responding to RF signal transmissions. For example, FIG. 1 shows an RF reader 124 , comprising an antenna and an RF transceiver, positioned to project RF signals toward container 100 . RFID tag 116 cannot detect these signals while in its home position.
[0018] Orientation sensor 108 is substantially identical to sensor 106 , but is attached to side 100 F, orthogonal to side 100 C. Thus, orientation sensor 108 likewise comprises a structure 110 provided with an enclosed space 112 . The enclosed space of sensor 108 similarly contains linear members 118 and 120 forming a “V”, and further contains a movable disk 114 having an RFID tag 116 embedded therein. The disk resides in a home position defined by the linear members when the sensor 108 is in its reference orientation as shown by FIG. 1 . Shielding material attached to the structure 110 of sensor 108 prevents its RFID tag 116 from detecting RF transmissions, when such device 116 is in the home position.
[0019] It will be readily apparent that container 100 could be placed on horizontal surface 102 in any of six orientations. That is, any of the six sides 100 A- 100 F of container 100 could be placed downward, in contact with surface 102 . However, only one of these orientations is correct or proper, namely, the orientation in which side 100 B is the downward side. Accordingly, the orientation sensors 106 and 108 have been designed so that their respective disks 114 will each be in the home position when side 100 B is the downward side, as shown in FIG. 1 . However, if container 100 is oriented so that any of its sides 100 A or 100 C- 100 F is the downward side, the disk 114 of one or both of the orientation sensors will roll out from the shielded region 122 , into an unshielded region 128 of enclosed space 112 . When this occurs, the RFID tag 116 in the disk 114 is enabled to detect RF signals.
[0020] It is important to emphasize that in order for the orientation sensors 106 and 108 to operate as described herein, they must both be attached to container 100 so that their respective structures 110 are in their reference orientations when side 100 B is downward. As indicated above, the structure of each orientation sensor is in its reference position when the point of the “V” formed by linear members 118 and 120 points directly downward, as shown by FIG. 1 . In this orientation, the “V” acts to guide disk 114 to the lower portion of space 112 and into shielded region 122 .
[0021] To assist a user in correctly attaching the orientation sensors to a container 100 , each sensor is usefully provided with visual indicia, such as two red dots 126 positioned along the lower edge of structure 110 . When attaching an orientation sensor to container 100 , the user would ensure that the edge with the red dots was the downward edge of the sensor, when side 100 B was the downward side of container 100 .
[0022] While FIG. 1 shows an embodiment of the invention directed to a container having six rectangular sides, it is to be emphasized that embodiments of the invention can be used with other types of containers as well, such as drums and pyramid type containers. In fact, embodiments of the invention can be used to detect improper orientation of a wide range of container types, as well as other objects that have two or more possible orientations. The principal requirement for use of the invention is that such containers and other objects must have only one orientation that is proper (or only one orientation that is improper).
[0023] Referring to FIG. 2 , there is shown sensor 106 in its reference orientation, so that disk 114 is in the home position. As described above, this occurs when side 100 B of container 100 is placed downward, in contact with surface 102 . As likewise described above, in this position RFID tag 116 resides in shielded region 122 of enclosed space 112 .
[0024] Referring to FIG. 3 , there is shown orientation sensor 106 when container 100 is oriented so that its side 100 D is the downward side in contact with surface 102 . In this orientation of the container, sensor 106 is rotated 90 degrees clockwise from its reference orientation. FIG. 3 shows that linear member 120 now inclines downwardly, away from shielded region 122 . Accordingly, disk 114 rolls down member 120 into unshielded region 128 of enclosed space 112 . This enables RFID tag 116 to detect RF signals.
[0025] Referring to FIG. 4 , there is shown orientation sensor 106 , when container 100 is oriented so that its side 100 A is the downward side in contact with surface 102 . In this orientation of the container, sensor 106 is rotated 180 degrees from its reference orientation. As shown by FIG. 4 , in this position disk 114 is pulled downwardly by gravity and out of shielded region 122 into unshielded region 128 of enclosed space 112 . This enables RFID tag 116 to detect RF signals. While not shown, the disk 114 of orientation sensor 108 would also move downwardly, from the shielded region to the unshielded region of such sensor.
[0026] Referring to FIG. 5 , there is shown sensor 106 when container 100 is oriented so that its side 100 F is the downward side in contact with surface 102 . In this orientation of the container, sensor 106 is rotated 270 degrees clockwise from its reference orientation. FIG. 5 shows that linear member 118 now inclines downwardly away from shielded region 122 . Accordingly, disk 114 rolls down member 118 into unshielded region 128 , enabling RFID tag 116 to detect RF signals.
[0027] While not shown, if container 100 was oriented so that side 100 E was the downward side in contact with the surface 102 , orientation sensor 108 would be rotated 90 degrees clockwise from its position in FIG. 1 . Accordingly, disk 114 of sensor 108 would move from its shielded region 122 to its unshielded region 128 in the manner described above. Moreover, if side 100 C became the downward side in contact with surface 102 , sensor 108 would be rotated 90 degrees counterclockwise, or 270 degrees clockwise, from its position shown in FIG. 1 . This would again result in disk 114 of orientation sensor 108 moving from the shielded region 122 to the unshielded region 128 thereof.
[0028] It is seen from the above that for each of the six possible orientations of container 100 , the RFID tags 116 of both orientation sensors 106 and 108 remain shielded from RF signals only when side 100 B is the downward side, as desired. When container 100 is in any of the other orientations, the RFID tag 116 of at least one of the sensors will be in its unshielded region 128 . Thus, improper orientation may be readily detected, by operating reader 124 to project an RF signal to container 100 . If an RFID tag 116 is unshielded, it will detect the signal, and transmit an identity code back to reader 124 in response. Accordingly, any RF transmission back to the reader from a tag 116 provides notice that container 100 is not in its proper orientation. It is to be noted that both of the orientation sensors 106 and 108 are necessary, in order to detect all possible improper orientations of the container 100 .
[0029] In the embodiment described above, RFID tag 116 functions as a passive device, in responding to signals projected from reader 124 . In other embodiments, an active RF device could be substituted for RFID tag 116 . Such active device could project an RF signal to a detector at some distance from a container, to indicate improper orientation of the container.
[0030] Referring to FIG. 6 , there is shown structure 110 of sensor 106 formed by joining layers or sheets of plastic 602 and 604 around their respective edges. Usefully, the two sheets have the same length and width dimensions, and each sheet has a raised edge or lip extending around its perimeter, on one of its sides. FIG. 6 shows sheets 602 and 604 , which may be clear or opaque, provided with raised edges 606 and 608 , respectively. To provide enclosed space 112 , the raised edges 606 and 608 are bonded together, such as by means of an adhesive 610 .
[0031] Referring further to FIG. 6 , there are shown linear members 118 and 120 and disk 114 contained in enclosed space 112 , as described above. Members 118 and 120 extend across the width of enclosed space 112 , for most effective RF shielding. Layers of metal foil 612 and 614 , or other suitable RF shielding material, are attached to plastic sheets 602 and 604 , respectively. The shielding layers provide shielded region 122 of enclosed space 112 , as likewise described above. To further enhance RF shielding, layers 612 and 614 are placed on the inner sides of sheets 602 and 604 , between the sheets and linear guide members 118 and 120 . To enable orientation sensor 106 to be readily attached to a container, a layer of adhesive 616 is applied to one of the sides of the sensor.
[0032] FIG. 6 further shows the edge of disk 114 covered with a coating or layer of RF shielding material 618 . This acts to prevent RF signal from penetrating the unshielded region 122 .
[0033] FIG. 7 shows a view of orientation sensor 106 that is similar to the view of FIG. 6 . However, in FIG. 7 the disk 114 , having moved into the unshielded region of enclosed space 112 , is not shown.
[0034] The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated. | Apparatus and method is provided for using low cost, passive RF sensor technology such as RFID tags, to determine whether containers or other objects are in a right-side-up orientation. A useful embodiment of the invention is directed to sensor apparatus for use in detecting an improper orientation of a conventional box or container with respect to a substantially horizontal surface. The apparatus includes a structure having two sides formed of plastic in spaced apart relationship, to define an enclosed space within the structure. Selected shielding material attached to the structure shields a specified region of the enclosed space against RF signals, the shielded region being located in the lowest portion of the enclosed space when the structure is in a reference orientation with respect to the horizontal surface. An RFID tag embedded in a disk is positioned in the enclosed space, the disk being sized to move freely within the space. A guide element guides the disk in moving between the shielded region and an unshielded region, when the structure is correspondingly moved between its reference orientation and an improper orientation corresponding to an improper orientation of the container. This allows a signal to be received from the RFID tag when it becomes unshielded, to indicate improper container orientation. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a dryer section for an apparatus for manufacturing webs of material, and, more specifically, to a dryer section for an apparatus for manufacturing paper, carton or cardboard.
2. Description of the Related Art
The sort of dryer sections discussed here are already known, that includes also those devices that contain an implement for compressing or smoothing the web, located either at the beginning or near the end of the dryer group of a dryer section (DE 44 07 405 A1). The effectiveness of such a pressure cylinder for compressing or smoothing the material web has reportedly not always been satisfactory.
It is therefore an objective of the present invention to improve on this sort of dryer section so that the effectiveness of the pressure cylinder for compressing or smoothing the material web will be significantly increased.
SUMMARY OF THE INVENTION
The present invention provides a dryer section with a significantly more effective compression and smoothening action by installing at least one pressure cylinder which is bounded by the second and the second to last dryer cylinder in the dryer group.
Quite preferable is an embodiment of this invention including a dryer section where one of the dryer rollers is assigned to the pressure cylinder with which it effectively interacts. This arrangement minimizes the overall spatial requirements of the dryer section. Furthermore, this sort of arrangement also simplifies the construction considerably.
Another embodiment of this invention incorporates an implement to control the moisture content and/or regulate the temperature distribution within the material web before this web approaches the pressure cylinder(s). This sort of adjustment substantially improves the effectiveness of the cylinder.
The dryer section of the present invention may also include a pressure cylinder which acts directly onto the material web instead of acting through the conveyer belt that supports the material web. This sort of arrangement prevents any impressions, e.g., imprint of the profile of the conveyer belt, into the surface of the material web from occurring.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIGS. 1, 2, 3 and 4 depict schematic side views of alternate embodiments of a dryer section of the present invention.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
The embodiments of dryer sections of the present invention that are described herein can generally be employed in conjunction with an apparatus to produce webs of material. For the purpose of illustrating this example it is from here on assumed that the described dryer section is a part of a machine that manufactures paper.
FIG. 1 shows a schematic side view of one particular part of a dryer section 1, more specifically, a side view of a section of the dryer group 3. This dryer group includes a number of different dryer cylinders 5, 7 and 9 whose centers are located in one plane. Below these dryer cylinders 5, 7 and 9 are carrier rollers 11 and 13 whose centers are located in a plane which in turn is parallel with the previously mentioned plane. The distance between the two planes is adjusted to provide several unobstructed paths 19 and 21 in-between the dryer cylinders 5, 7 and 9, and the corresponding carrier rollers 11 and 13. The material web 15, sketched as a dotted line near the oncoming side of the revolving dryer cylinder 5, is allowed to move through these openings and then further along a meandering path around the dryer cylinders 5, 7 and 9 and the carrier rollers 11 and 13. The clearance in-between these rollers must be wide enough to allow passage of the material web together with a conveyer belt 17 along its side to press and stabilize it. This conveyer belt 17 will from now on also be referred to as a flexible drying sieve. The four paths of free passage 19 and 21 are basically interrupted by the turn of the material web and the flexible drying sieve around carrier rollers 11 and 13. As shown in FIG. 1, it is possible that two suction boxes 23 and 25 can be placed in-between these two path segments so that they produce a negative pressure which sucks the material web towards the conveyer belt and thus stabilizes the transport of the web of material.
FIG. 1 also depicts some scrapers 27 which are commonly employed to keep incoming paper away from the surface of the dryer cylinders 5, 7 and 9. The diameters of the dryer cylinders 5 and 9 are kept a little larger than the diameters of the carrier rollers 9 and 11. The ratio of the diameters to one another can be adjusted to the material properties of the web. It is also an option to use the same diameter for the dryer cylinders and the carrier rollers so that the carrier rollers could potentially be replaced by dryer cylinders. It is furthermore possible to construct the carrier rollers 9 and 11 such that the material is sucked against the surface of these carrier rollers 9 and 11 in order to stabilize the transport of the material web through the apparatus.
Provisions are furthermore made for a guide roller 29 located a specific distance above the dryer cylinder 7. This guide roller 29 basically detaches the conveyer belt 17 from the web of material 15. While the conveyer belt travels quite a long distance away and then back to the dryer cylinder 7, the material web 15 actually sticks directly to the surface of the dryer cylinder 7. The conveyer belt being pulled away from the dryer cylinder 7 actually creates a little free space 31.
The way in which the material web 15 comes into direct contact with the dryer cylinder 7 permits the moisture to evaporate without any obstructions. A further advantage is created by the fact that the conveyer belt 17 does for a brief moment not press the material web 15 against the surface of the dryer cylinder 7. This allows the web to shrink a little which decreases the residual tensile stresses into the transverse direction within the web.
FIG. 1 illustrates how a pressure cylinder 33 can be fitted into the free space 31. This pressure cylinder 33 is juxtaposed to the dryer cylinder 7, so that their adjoining surfaces press against each other. It is furthermore suggested to wrap some soft synthetic fabric around the pressure cylinder 33 which helps conform the mating surface of the pressure cylinder 33 to the contour of the dryer cylinder 7.
The close contact between the pressure cylinder 33 and the dryer cylinder 7 effectively smoothens the web of material 15, and the compression helps densify the material web 15. This sort of effect lets the dryer cylinder 7 also act as a smoothening cylinder.
It is conceivable that if the free space 31 is large enough and appropriately shaped, a dehydration band (not shown in FIG. 1) may be placed in-between the cleft between the pressure cylinder 33 and the dryer cylinder 7. Such a dehydration band would help to reduce the moisture level in the material web by absorbing the water that is mechanically squeezed out of the web by the combined action of the pressure cylinder 33 and the dryer cylinder 7. In such an arrangement the pressure cylinder 33 acts as a compression implement that effectively increases the density of the material web. The densification of the material further improves the degree of dryness, especially if the material is some sort of porous paper. In yet another configuration of this dryer section, the pressure cylinder 33 can be fabricated so that its surface absorbs liquids. It is possible, for example, that the surface of the cylinder is made out of something porous, thus allowing it to absorb water. Such a design would eliminate the use of a dehydration band.
To ensure that the conveyer belt 17 wraps around a portion of the dryer cylinder 7, two support rollers 35 and 37 can be placed--looking along the travel direction of the material web--before and after the guide roller 29. This provision also helps to reduce the extent of the free space 31. It is also possible to control the number, location and the extent of the arc segment along which the conveyer belt 17 wraps around the dryer cylinder 7 by appropriately placing the support rollers 35 and 37. The support rollers 35 and 37 can be located, for example, so that the conveyer belt 17 contacts a particularly large portion of the surface of the dryer cylinder 7. This effectively increases the drying capacity of the dryer section without making any further adjustments to the apparatus or adding any additional features.
FIG. 2 shows a side view section of a dryer section with a modified dryer group 30. This dryer group 30 includes dryer cylinders 50, 70 and 90 located in an upper plane as well as dryer cylinders 80 and 82 in a somewhat lower plane. In addition, there are provisions made for a first carrier roller 110 that is located just below the dryer cylinders 50 and 70, and a second carrier roller 81 which is placed just above the dryer cylinders 80 and 82. The web of material 15 is indicated with a dotted line near the dryer cylinder 50 on the side where the conveyer belt and material web wrap onto dryer cylinder 50. The web of material is guided, while in close contact with the conveyer belt, in a meandering way around the dryer cylinders 50, 70, 80, 82 and 90 as well as around the carrier rollers 81 and 110. FIG. 2 shows two free spaces within the so called free paths 19 and 21 where material travels around carrier rollers 81 and 110. They are referred to as free paths because for these short distances neither the web of material nor the conveyer belt are supported by any rollers or cylinders. These free spaces are again utilized for suction devices 23 and 25 which serve to stabilize the passage of the material web 15. The dryer section 30 is equipped, as before, with scrapers 27, of which only one example is shown. They serve again to keep incoming paper away from the surface of the dryer cylinders, and prevent it from getting tangled around the dryer cylinders.
The diameters of carrier rollers 110 and 81 are kept a little smaller than the diameters of the dryer cylinders 50 and 90. It is also an option to use the same diameter for the dryer cylinders and the carrier rollers, so that the carrier rollers could potentially be replaced by dryer cylinders. It is furthermore possible to construct the carrier rollers 110 and 81 with suction acting from within to prevent the material web 15 from becoming detached.
A guide roller 29 is placed above the carrier roller 81. It is the purpose of guide roller 29 to lead the conveyer belt 17 at a specific distance away from the carrier roller 81. In addition to that, support rollers 35 and 37 are incorporated to determine the location and the extent of the arc segment along which the material web 15 and the conveyer belt 17 wrap around the dryer cylinders 70 and 90, respectively. At the same time the support rollers 35 and 37 define the extent and shape of the free space 31, located just above the guide roller 29. The top border of this free space 31 is outlined by the conveyer belt 17, while the bottom border is defined by the open surface of the dryer cylinders 80 and 82. The side borders of the free space, on the other hand, are defined by the so called free paths 19 and 21 where the web of material 15 travels unsupported by any rollers as well as the path taken by the material web 15 as it is guided over the carrier rollers 81. The support rollers 35 and 37 may potentially be utilized to control the free tension acting between the two dryer cylinders 70 and 80, or between another set of two dryer cylinders 70 and 80, respectively, i.e., generally to minimize these tensile forces. Such adjustments in tension are essential for producing webbed material at a fast rate without sacrificing control over the movement of the web. Further, the location of the support rollers may be influenced by the desired arc of contact between the material web 15 and the conveyer belt 17 as they wrap around the dryer cylinders, or the location of the support rollers may be influenced by the amount of free tension acting between adjacent dryer cylinders. Such arrangements optimize the manufacturing process of the material webs.
As the material web 15 travels unsupported by any rollers through the so called free space, moisture is allowed to freely evaporate from the unobstructed surface of the material web. Since the web is not constrained by any transverse forces pressing it against the surface of the carrier rollers 81, it is in a position to shrink. This inhibits the development and actually enables for brief moments the relaxation of residual stresses in the transverse direction.
If the free space is constructed such that the center axis of the guide roller 29 is sufficiently far enough away from the center axis of the carrier roller 81, then there is in this version of the dryer section room enough to incorporate a pressure cylinder 33 into the free space 31, as it was described in FIG. 1 for the previous version. In the following example, illustrated in FIG. 2, the pressure cylinder 33 is depicted adjacent to the dryer cylinder 80 at an arc segment where the material web 15 travels along the surface of the dryer cylinder, not accompanied by the conveyer belt 17. A line consisting of dots and dashes illustrates how a dehydration band 39 could be inserted between the pressure cylinder 33 and the dryer cylinder 80 so that it would run for a brief part of the way adjacent to the material web 15. The pressure exerted upon the material web 15 by the force of the pressure cylinder 33 pushing against the dryer cylinder 80 squeezes some of the moisture out of the material web 15, which then is absorbed by the dehydration band 39. The pressure cylinder 33 acts in this arrangement as a compression unit. Without the dehydration band 39, the pressure cylinder 33 merely acts as a smoothening implement. The pressure cylinder 33 can be constructed so that its surface is made out of a porous material. This makes the surface itself into an alternative tool to absorb moisture that could replace the dehydration band 39, just as it was explained in the previous version.
Another improvement feature is the second conveyer belt 17' that acts as a support to prevent the web of material 15 from detaching from the dryer cylinders 80 and 82. The path of the second conveyer belt 17' is shown to lead through carrier rollers 41 and 43, around a portion of the dryer cylinder 80, along the free path 19 to the carrier roller 81, and then along the second free path 21 to another dryer cylinder 82. The dryer group 30 is therefore in parts developed into a double lined dryer group. The previous dryer group 3, shown in FIG. 1 is therefore in contrast a simple "top felted" dryer group, where the conveyer belt 17 is guided above the dryer cylinders 5 through 9, up to the beginning of the dryer group 3. The dryer group 30, as it is shown in FIG. 2, must also be regarded as a quasi, single line, "top felted" dryer group within the regime of the dryer cylinders 50 and 70. More dryer cylinders can be added onto the dryer group 30 next to the dryer cylinder 90, so that this would then also be considered as quasi, single line, and "top felted" group. The possibility also exists to divide the dryer group before the dryer cylinder 50, and after the dryer cylinder 90, thus creating two separate group entities.
FIG. 3 is a simplified representation of the dryer group which was previously shown in FIG. 2 as dryer group 30. Since the same configurations are shown in FIGS. 2 and 3, the same reference numbers are used for the corresponding elements. The dryer group 30 in FIG. 3 shows again a number of dryer cylinders 50, 70 and 90, located along an upper horizontal plane. Dryer cylinders 80 and 82 are lined up along a lower horizontal plane where they are stacked in alternating steps between the upper cylinders 70 and 90, and after cylinder 90, respectively. A carrier roller 110 is shown placed in the same position as before, between the dryer cylinders 50 and 70. A suction device 23 is inserted between the so called free paths 19 and 21 to and from the carrier roller 110. The suction device 23 is applied to the carrier roller 110, and is used to stabilize the movement of the material web 15 as it traverses the free paths 19 and 21.
A support roller 35 is placed--looking along the travel direction of the conveyer belt 17--after the dryer cylinder 70. Following this, the conveyer belt 17 moves from the support roller 35 directly to the next dryer cylinder 90, and wraps around a portion of the dryer cylinder 90 before it is taken up by a second support roller 37 which is placed adjacent to the second dryer cylinder 90. The web of material 15 moves along a meandering path around the dryer cylinder 50, then the carrier roller 110, and then around another dryer cylinder 70. The material web 15 then winds around the lower dryer cylinder 80, next around the upper dryer cylinder 90, and finally around the lower dryer cylinder 82. For additional support a second conveyer belt 17' is utilized in the regime of the lower dryer cylinders 80 and 82, in order to press the material web 15 against the surfaces of these lower dryer cylinders 80 and 82 while carrier rollers 41, 43 and 45 help to keep the conveyer belt 17' along the right path.
The dryer group 30 is provided with scrapers 27 which are acting on the surfaces of the dryer cylinders 50, 70 and 90, as well as the dryer roller 80. Also the dryer cylinder 82 is equipped with a scraper.
A pressure cylinder 33 is installed at a location where the material web 15, while not being supported by either of the conveyer belts, is winding around the dryer cylinder 80. The purpose of the pressure cylinder 33 is to press the material web 15 against the dryer cylinder 80. A dehydration band 39 is inserted in-between the pressure cylinder 33 on one side and the dryer cylinder 80 as it is indicated by a line of dots and dashes (FIGS. 2 and 3). The function of the dehydration band 39 is to absorb the moisture that is being squeezed out of the material web 15. In such an arrangement, the dryer cylinder 80 acts as a smoothening cylinder. If the surface of the dryer cylinder 80 is made out of a porous substance, the dehydration band 39 may be eliminated.
FIGS. 1 through 3 show versions of a dryer section where the pressure cylinder 33 acts in conjunction with a dryer cylinder. The walls of the dryer cylinder preferably are enforced in order to take the pressure of the pressure cylinder 33. Also the bearing of the dryer cylinder needs to be enforced accordingly in order to sustain the pressure of the pressure cylinder 33. It is furthermore possible to incorporate deflection control into the dryer cylinder in order to compensate for the deflection of the larger dryer cylinder caused by the force exerted by the smaller pressure cylinder 33, and in order to develop a certain distribution of the compressive forces across the section of the cylinder. It is also possible to vary the force with which the pressure cylinder pushes on the material web in order to adjust the pressure to a desired value.
FIG. 4 shows a sectional side view of another dryer section with a modified dryer group 130, of which two dryer cylinders 150 and 170 are depicted which are situated in a horizontal plane. The sketch also shows two carrier rollers 110 and 140 in a somewhat lower plane. These carrier rollers 110 and 140 are displaced by a certain distance in the direction of the "overall movement of the material web" within the machine, which is indicated by a double arrow at the bottom of FIG. 4. A dashed line indicates the material web 15, supported by the conveyer belt 17, as it is in the progress of winding onto the dryer cylinder 150. From here, the material web 15 and the conveyer belt 17 travel unsupported by any roller or cylinder across a so-called free path 19, and onto another carrier roller 110. The material web 15 and the conveyer belt 17 then wind together from the carrier roller 110 before they embark on a second free path 19'. The material web 15, which traveled outside of the conveyer belt 17 around the carrier roller 110, then adheres to a first pressure cylinder 33, and then in-between a gap formed by this first pressure cylinder 33, and a second pressure cylinder 33', which is located just above the first pressure cylinder 33. In the mean time, the conveyer belt 17 extends along a separate path. To wit, the conveyer belt 17 is picked up by two widely spaced out guide rollers 29 and 29', which carry it along a path that describes a large free space 31. The two pressure cylinders 33 and 33' are confined within this free space 31, bordered by the path of the conveyer belt 17. The material web 15 and the conveyer belt 17 then join back together and travel along another free path 19', which brings the material web from the surface of the pressure cylinders 33 to the surface of the carrier roller 140. From there, the material web 15 and the conveyer belt 17 move along another "free path" 21' to another dryer cylinder 170.
The embodiment shown in FIG. 4 is characterized by the fact that the pressure cylinder 33 does not act together with the surface of a dryer cylinder but instead with the surface of another pressure cylinder 33'. The material web 15 is led in-between these two pressure cylinders 33 and 33', which act as smoothening cylinders onto the material web 15. A slightly different arrangement which is not shown in FIG. 4 employs a dehydration band that moves along with the material web 15 in-between these two pressure cylinders 33 and 33', which would in this case act as compression cylinders onto the material web 15.
It follows from the above description that pressure cylinders 33, which were before explained and are shown in FIGS. 1 through 3, can also act in conjunction with carrier rollers, especially when these carrier rollers are enforced to withstand the compressive forces.
It is common to all these versions of the present invention that the dryer group has at least one pressure cylinder which acts onto the material web in order to help squeeze some of the water out of this web, thus acting as a compression cylinder. In contrast, the pressure cylinder can also smoothen the surface of the material web and densify it, thus acting as a smoothening cylinder instead. The dryer group can be constructed in an especially compact fashion if a pressure cylinder is installed into the "free space" that is formed by separating the material web 15 from the conveyer belt 17, and leading the conveyer belt 17 by means of one or more guide rollers 29 or 29', respectively, around a path that basically describes the circumference of this "free space". The separation maneuver can only be executed in such a way that the conveyer belt is lifted up or carefully moved away from the material web as both are near a dryer cylinder. Else it is possible to separate the conveyer belt from the material web by leading both of them freely above a dryer cylinder or a carrier roller, such as is illustrated in FIG. 2.
By making special arrangements for the placement of the pressure cylinder within the confines of the dryer group it is possible to gain particularly good control over the moisture content in the material web and also to improve the quality of the surface of the material web. This dryer group allows a certain moisture content and a desired surface quality for the material web before the web moves on to another dryer group. The moisture content and the quality of the surface of the web of material can thus very well and very accurately be predicted and they can be varied to what ever is desirable for a given product. It is possible to predetermine the moisture content and the quality of the surface which the web of material will attain within the range of a dryer group, independent of the way in which the material web is transferred to the next group. A dryer group of this sort can thus be randomly combined with other dryer groups without any repercussions to the outcome of the moisture content and the quality of the surface of the web of material by the way the groups are configured with respect to one another. It is also possible to integrate such a dryer group at any location within a dryer section and to choose the location for the placement of the pressure cylinders only by criteria dictated by the moisture content and the material properties of the web of material.
It is furthermore common to all the above mentioned versions of this invention that an implement to balance the moisture level and/or temperature distribution across the web of material 15 is installed in front of the pressure cylinder 33, which in turn smoothens the material web 15. Especially notable is an arrangement that utilizes a steam blower box, which blows steam onto the material web 15 before this passes through the smoothening slot that is formed by the pressure cylinder. This sort of arrangement can be employed for the case where a pressure cylinder is working in conjunction with a dryer cylinder or a carrier roller, as well as for the case where two smoothening cylinders 33 and 33' are working in conjunction with one another.
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | The invention is directed to a dryer section for an apparatus to produce webs of material, such as paper, carton or cardboard which shall consist of a number drying cylinders and carrier rollers, at least one dryer group which shall include at least one conveyer bend to direct the continuous material web along a meandering path around these drying cylinders and carrier rollers, and with at least one pressure cylinder to compress or smoothen the web of material. The pressure cylinder is located within the dryer group 3, 30 or 130, respectively, such that it is located within a region that is contained within the second and the second-to-last dryer cylinder of the dryer group. | 3 |
CROSS-REFERENCE TO RELATED PATENTS
This application is related to U.S. Pat. Nos. 2,966,356, 3,251,109, 3,279,745, 4,304,403, 4,651,989 and 5,456,462 issued to the inventor of this application. The disclosures of these patents are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
This invention relates to belts having adjustable buckles which, as an example of use, may be used in flag tag games but which may also be used for many other purposes.
Belts such as specialty tool belts and flag-tag belts generally need to be constructed of several different sizes. First sizes are provided for smaller users with smaller waists who are not be able to wear larger sizes. Second sizes are provided for larger people which when used on smaller users result in dangling extensions of the belt. These extensions can be dangerous as well as inconvenient.
One belt design which attempts to correct this problem is disclosed in U.S. Pat. No. 3,355,744 and describes a belt and engaging member onto which the excess belt amount can be looped to prevent the belt end from flopping. However, it is often the case that the user will forget to engage the belt in said element, thereby defeating the purpose of this provision.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a safe plastic flexible belt buckle or fastener that is economical to manufacture, and which further, can be used effectively by users of all sizes. The buckle can be used with wide or thin belting. The buckle provides for automatically securing excess loose running and belting in at least one loop on the buckle. Thus, users are less likely to forget to secure loose ends of the belting.
The invention in its broadest aspect utilizes belt buckles which have pluralities of slots allowing substantial portions of belting to be accumulated on the buckles in overlapping loops.
In accordance with one embodiment of the present invention, a belt comprises a length of flexible material in the form of a web, sufficiently long to encircle the waist of a player of the game and having at least one removable flag attached thereto. A first end portion of the belt has a slot therein wherein the belt is inserted through the slot to form an adjustable loop which is connected to a buckle, while a second end portion of the belt has a leading edge which is detachably connected to the buckle. The buckle comprises a body portion having a mid-portion, a first end and a second end. The first end has a pair of closed slots separated by an intermediate strut and a first partially open slot outboard of the closed slots. The body further has a single closed slot adjacent the second end with a friction element associated with the single slot, as well as a second partially open slot outboard of the single closed slot. The loop formed at the first end of the belt extends through the pair of closed slots and is looped around the intermediate strut, separating the pair of closed slots. In order to attach the second end of the belt to the buckle, the leading edge of the second end is fed through the single closed slot at the second end, over the mid-portion of the body and strut separating the pair of first slots, through one of the first slots and around the strut separating the pair of first slots from the first partially open slot in the first end. The belt is then passed through the partially open slot at the first end, back over the body and through the second partially opened end slot. Consequently, the belt has an adjustable length selected by accumulating a substantial selected length of the belt in the loop and a frictional coupling with the buckle that maintains the selected length when lateral stress is applied to the belt in an attempt to move the flag.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
FIG. 1 is a perspective view of a first embodiment of the flag-tag belt in accordance with the present invention shown in an open condition;
FIG. 2 is a front view of a buckle used with the belt of FIG. 1 having a second end portion of the belt attached thereto;
FIG. 3 is a side view of the buckle of FIG. 2;
FIG. 4 is a side view showing attaching the free end to the buckle;
FIG. 5 is a view similar to FIG. 4, but showing the belt trained through slots in the buckle;
FIG. 6 is a side view showing a first embodiment of a coupling arrangement for coupling a flag to the flag-tag belt, showing the coupling connected;
FIG. 7 is a side view similar to FIG. 6, showing the coupling oriented at 90° to FIG. 6;
FIG. 8 is a side view similar to FIG. 6, showing the coupling disconnected;
FIG. 9 is a side view similar to FIGS. 6 and 8, showing another embodiment of the coupling arrangement for flags which uses a socket and projection.
FIG. 10 is a perspective view of a second embodiment of the flag-tag belt in accordance with the present invention shown in an open condition;
FIG. 11 is a front view of a buckle used with the belt of FIG. 10;
FIG. 12 is a rear view of the buckle of FIG. 10;
FIG. 13 is a side view of the buckle showing attaching the free end of the belt to the buckle by training the belt through slots in the buckle;
FIG. 14 is a view similar to FIG. 13, but showing the belt pulled taught;
FIG. 15 is a perspective view of a second embodiment of a flag coupling arrangement showing a flag being inserted in a loop on the belt;
FIG. 16 is a view similar to FIG. 15 showing the flag being pulled through the loop;
FIG. 17 is a view similar to FIGS. 15 and 16 showing the flag positions in the loop and ready for play; and
FIG. 18 is a view similar to FIGS. 15-17 showing the flag being pulled from the loop during play.
DETAILED DESCRIPTION
Referring now to FIG. 1, there is shown a first embodiment of a belt 10, in accordance with the present invention, which is used in play flag tag games wherein at least one flag 12 is detachably mounted to the belt by a coupling 16. The belt 10 has an elongated web portion 20 having a first end portion 22 and a second end portion 24, which are joined by a buckle 26. The belt 10 is preferably made of a plastic material such as polyethylene terafilate, reinforced polyvinyl chloride (PVC) or vinyl resins including PVC. In the embodiment of FIGS. 1-5, the belt has four ribs 27 extending along the outside surface 28 thereof with the inside surface 29 being smooth. Referring now mainly to FIGS. 2-5, the buckle 26 includes a first end 30 and a second 31 joined by a middle section 32. The belt buckle 26 has a first slot 35, a second slot 36, a third slot 37, a fourth slot 38, a fifth slot 39, a sixth slot 40 and a seventh slot 41. Separating the slots 35-41 are first strut 42, second strut 43, third strut 44, a fourth strut 45 and a fifth strut 46. Adjacent the first end 30 of the buckle 26, there is a land 55 and adjacent the second end 31 there is a land 56 which has a hole 57 therethrough for hanging the belt 10 on a wall hook, or the like. A central land 58 is disposed between the slots 35 and 36 and has a stud 59 projecting therefrom which has a head 60. The head 60 is used to secure the end 24 of the belt 10 to the first land 60 by passing through an aperture 62 in the first end of the belt. A rim 64 extends around the periphery of the belt buckle 26.
As is seen in FIGS. 3, 4 and 5, the end 24 of the belt 10 is passed through the first slot 35 either prior to or after anchoring the end with the belt with the head 60 of the stud 59. The end 22 of the belt is then attached to the belt buckle 26. This is done so that a substantial length of the belt 10 may be accumulated on the belt buckle 26, if the length of the belt is such that in order for it to fit on the player, the free end 22 of the belt will dangle loosely from the buckle. In order to accumulate a substantial portion of the belt's length on the buckle, it is threaded back and forth through the buckle as is seen in FIG. 5.
As is seen in FIG. 4, the free end 22 of the belt 10 is initially threaded through the second slot 36, passed over the head 60 of the stud 59. Depending on the waist size of the wearer, the end 22 of the belt 10 may then be passed out through the seventh slot 41 or may be passed through the second slot 37. The belt 10 can then loop around the strut 45, passed through the third slot 38 and then over itelf and through the fourth slot 39. If there is still excessive length in the belt 10, the belt can then be looped around the strut 44 and passed through the fifth slot 40 before again being passed over itself and inserted through the sixth slot 41 in the belt buckle 26. Consequently, the belt buckle 26 can accumulate about one foot of belt length thereon and thus keep the end 22 of the belt from dangling if the player has a relatively narrow waist. For larger players, the belt need not be threaded through all of the slots and the end of the belt can rather be inserted through a loop or other fitting such as the bracket 70 shown in FIG. 1 which has a couple of inwardly projecting pins 71 an 72 beneath which the free end 22 of the belt can be retained.
By having the belt buckle retained to the end 24 on the middle land 58 by the stud with the head 60, the buckle 26 can be pivoted adjacent its ends 30 and 31 so as to alternatively expose the back side of the buckle in order to facilitate ease of inserting the belt 10 through the slots 36-41.
Referring now to FIGS. 6-9, there is shown a first embodiment of a suction coupling 100 for coupling at least one of the flags 12 to the belt 10. The suction coupling 100 includes a slider support 102 which receives the web 20 of the belt 10 through a slot 104. The slot 104 has a sufficient width to receive a relatively thick, one inch width belt or a relatively thin but wider belt, which extra width is accommodated by the bends 106 and 108 in the slot 104. Projecting at an oblique angle ∝ with respect to the slider support 102 is a first suction cup 110 which is unitary with and molded from the same material as the slider support. By orienting the opening 112 of the suction cup 110 outwardly or away from the slider support 102, the expense of making the coupling, which is attached to the belt 10, is greatly reduced. This is because there is no need to weld the cup 110 to the slider 102, which was necessary in the prior art suction cup couplings.
The suction cup 110 has a cylindrical side wall 114 which is relatively thin and a base 116. The cup 110 and mounting slider 102 form a first portion of the suction coupling 100.
The second portion of the suction coupling 100 is the attachment comprised of a suction cup 120 and a flag attachment buckle 122 which is attached to the suction cup 120 by a stem 124. Suction cup 120 has a cylindrical wall 126 which is relatively flexible base 128. As is seen in FIG. 8, the suction cup 120 has an outer diameter D1 which complements the inner diameter D2 of the suction cup 110. Consequently, the suction cup 120 is snugly received within the suction cup 110. In order to facilitate easy insertion of the suction cup 120 into the suction cup 110, an air hole 130 is formed in one or both of the bases 128 or 116, of the suction cups 120 and 110. When the suction cups are inserted and pressed together, air trapped within the confines thereof vents through the air hole 130 as the suction cups are axially slid together. When the suction cups are pulled apart by yanking on one of the flags 12 or 14 attached to the buckle 122, there is audible report or "pop" as the suction cup 120 rapidly disengages from the suction cup 110.
As is seen in FIG. 7, in order to enhance the pop, the buckle 122 is also offset at an angle Θ from the suction cup 120. This increases friction between the walls 126 and 114 when the 12 flag attached to the buckle 122 is yanked, thus increasing the force and, therefore, the loudness of the sonic pop. Further to this point, by having the flag attachment buckle 122 offset by both angle Θ and angle α with respect to the slider support 102, the flag 12 extends at a double oblique angle with respect to the belt which results in a louder "pop" when the suction cups 110 and 120 separate. When the slider support 102 is on the belt 10 as is shown in FIG. 1, with the slots 136 and 138 of the attachment buckle 102 extending at 90° as is seen when comparing FIGS. 6 and 7, there are twisting and bending forces on the suction coupling 16 which result in an increased separation force and in the louder "pop."
Referring now to FIG. 9, there is shown suction coupling 100' in accordance with a second embodiment of the couplings 16 attaching the flags 12 to the belt 10. The second suction coupling 110' is substantially identical to the first suction coupling 100, but includes a projection 152 in the suction cup 110' which is received in a socket 154 in the suction cup 120'.
Referring now to FIG. 10, there is shown a second embodiment of the invention which uses a belt wherein at least one flag 212 or 214 is detachably mounted thereon by a suction coupling 216 or optionally, by a second type of coupling 218 to be further discussed hereinafter. The belt 210 has an elongated web portion 220 having the first end free end portion 222 and a second end portion 224 which are joined by a buckle 226. The belt 210 is preferably made of a plastic material such as polyethylene terephthalate, reinforced polyvinyl chloride (PVC), or vinyl resins including PVC.
Referring now to FIGS. 11 and 12, where the front and back views of the buckle 226 are shown. The buckle includes a first end 228 and a second end 230 joined by a mid-section 232. A pair of slots 234 and 236 are disposed proximate the first end 228 and are separated by an intermediate strut 238. An open slot 240 is positioned outboard the pair of slots 234 and 236 and is separated therefrom by a strut 242. The open slot 240 has its ends defined by lips 244 and 246, which define recesses 248 and 250 therebehind and are spaced by an opening 252.
At its second end 230, the buckle 226 has a single slot 256 which is separated from an end slot 258 by a strut 260. The single slot 256 has a pair of teeth 262 therein with rounded ends which oppose a pair of indentations 264 in the strut 260. The second open slot 258 is similar to the first open slot 240 in that it has lips 266 and 268 that are separated by a space 270 and which define recesses 272 and 274 thereunder. As is seen in FIG. 12, the buckle 226 has a row of conical projections 276 thereon which are pointed for engagement with the web 20 (FIG. 10) of the belt 210. The buckle 226 also has an aperture 278 therethrough which receives a hook (not shown) for hanging the belt 220.
Referring now to FIG. 13, it is seen that the first end of the belt 210 is formed into a loop 280 by inserting the tapered leading edge 282 of the second free end 224 of the belt through a slit 284 adjacent the tapered free edge 286 of first end 222. The loop is formed around the strut 238 with the web 220 of the belt passing through the slots 234 and 236. By adjusting the length of the loop 280 so as to accumulate either more or less of the web 220 of the belt 210, the length of the belt is selected.
In order to attach the second end 224 of the belt 210 to buckle 226, second end 282 is first passed through the single slot 256 at the second end 230 of the buckle from the underneath or backside of the buckle. The leading edge 282 of the web 220 is then passed through the slot 236 of the pair of slots 234 and 236 from the front side of the buckle over the loop 280. The web 220 is then inserted in the open slot 252 at the first end 228 of the buckle 226 and then passed back over belt portion 288 and the mid-portion 232 buckle and inserted through the second open slot 258 at the second end 230 of the buckle. If there is substantial length of the second end portion 224, it is simply tucked behind the web 220 of the belt.
When the web 220 of the belt 210 is inserted through the single slot 256 and pulled so as to be slightly tensioned about the wearer's waist, the frustoconical projections 276 on the rear face of the buckle 226 bite into the web to help restrain the web. The portion of the web 288 formed when the end 224 is passed through the slot 236 is tensioned when the second end 224 is pulled tight. This causes the teeth 262 to press into the web 220 and firmly fix the length of the belt 210. The end 224 is then passed through the open slot 40 and again pulled tight to flatten the belt portion 288, as is shown in FIG. 14. Finally, the end portion 224 is folded over the portion 288 and passed through the second open slot 258 and tensioned. If the end portion 224 is excessively long, then it can be tucked beneath the web 220 of the belt 210.
Referring now to FIGS. 15-18, there is shown a second embodiment of structure for attaching the flags 312 to the belt 210, which is considerably less expensive than the embodiments of FIGS. 6-9. In this embodiment, a buckle 360 having slots 362 and 364 therein for receiving the web 320 of the belt 210 has a relatively rigid loop 366. The relatively rigid loop 366 has a selected fixed diameter D4 which is less than the width D5 of the flag 312. The flag 312 has a tapered leading edge 370 which is passed through the loop 366 to attach the flag 312 to the belt 210. The flag 312 has a trailing end 372 which includes a tapered trailing edge 374 having a pair of slits 376 which extend laterally inward from the edges of the flag 312. Behind the slits 376 is a slot 378 in the flag 312 through which the tapered trailing edge 374 is inserted so that the slits hold this trailing end 372 in a loop 379. As is seen in FIG. 17, the trailing end 372 of the flag 312 is enlarged by the loop 379 in order to hold the flag in the loop 366 of the buckle 360. As is seen in FIGS. 15 and 16, the flag 312 is pulled through theloop 366 of the buckle until the loop 379 of the flag engages the loop 366 of the buckle. As is seen in FIG. 18, when tension is applied to the flag 212, the enlarged portion formed by the loop 379 is squeezed so as to slide through the loop 366 and free the flag 212 from the belt 210. While this approach does not provide for the "pop" of the suction coupling of FIGS. 6-9, it does provide a relatively inexpensive flag-tag arrangement.
From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. | Adjustable belts include new and improved belt buckles which allow for convenient adjustment of belt lengths, as well as secure and easily adjustable couplings of the two ends of the belts. This is accomplished by providing the belt buckles with an arrangement of slots and struts around which the belt is looped to selectively accumulate its length thereon and through which the belt is trained, so as to frictionally retain the belt on the buckle while determining the length of the belt. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to the field of telemetry, and in particular to a medical apparatus for programming and/or monitoring an implantable medical device over a radio-based wireless network, and such a system.
[0003] 2. Description of the Prior Art
[0004] Telemetry is a generic term for techniques for conveying measuring data from one point to another, usually by means of radio. In particular, within the medical field telemetry systems are generally used for enabling radio-frequency (RF) communication between an implantable medical device (IMD) such as a pacemaker, and an external monitoring device. The frequency spectrum used for wireless communications between implanted medical devices and external equipment is about 400 MHz, but for wireless medical telemetry services in general several frequency bands may be used. Within a medical telemetry system crucial physiologic data is transmitted, and it is critical to ensure that data is not lost or delayed. Medical telemetry is a low-power radio system, and although relatively short distances are usually employed within such systems, there may nevertheless arise a need for considering reception aspects. One such consideration is related to the fact that electromagnetic fields emitted in a room will give rise to standing wave patterns. The energy that a receiver will be able to receive is varying as a function of the position in the room. Using multiple antennas, resulting in so called spatial diversity, may minimize the effects of this.
[0005] U.S. Pat. No. 6,167,312 discloses such a device for use in communication with an implantable medical device. The device is provided with a spatial diversity antenna array including at least one antenna permanently and fixedly mounted to the housing of a monitor or programmer, and an additional antenna removably mounted to the housing.
[0006] This known telemetry system, although suggesting the use of spatial diversity in order to facilitate the reception of signals from an implantable device and also the transmission of signals to the implanted device, still has several drawbacks regarding the signaling. For example, as mentioned above, the system comprises a removable antenna, but the use of it entails the physician having to move the antenna around until an acceptable reception is obtained. Therefore, should there arise a need to move a patient from one place to another, for example from an examination room to an X-ray examination room, the tedious reception/transmission optimization would have to be performed once more. Thus, the apparatus described requires the physician operating it to perform a kind of an antenna reception optimization, which is a time-consuming and also unreliable method. Further, the range of said removable antenna is limited, and dependent upon the length of a coiled cord by means of which the removable antenna is coupled to a transceiver within the programmer.
[0007] Furthermore, such a programmer is relatively expensive, and it would be desirable and convenient to be able to easily move the programmer, for example between different wards in a hospital, with retained communication quality, to thereby avoid having to buy several costly programmers.
[0008] There is thus a need in a telemetry system, for improved two-way communication of signals between a monitoring device and an implantable medical device, both forming parts of a medical system for programming and/or monitoring the implantable medical device over a radio-based wireless network. In particular, it would be desirable to provide a reliable communication, which overcomes the aforementioned shortcomings of known systems and devices.
SUMMARY OF THE INVENTION
[0009] An object of the present invention is to provide reliable radio communication within a telemetry system, the communication being easily and conveniently optimized, eliminating or at least reducing the risk of a communication failure between an implantable medical device and a monitoring device due to fading and/or a low signal strength.
[0010] It is a further object of the present invention to provide a medical apparatus and system, by means of which spatial diversity is achieved.
[0011] These objects are achieved in accordance with the present invention by a medical apparatus having a monitoring device and at least two antenna devices, the medical apparatus enabling programming and/or monitoring of an implantable medical device over a radio-based wireless network. The at least two antenna devices in the system are provided as separate, stand-alone units, i.e. not forming part of the programmer or monitoring device. Thus it is possible to place the antenna devices in an optimal way, preferably at stationary locations, such as for example wall and/or ceiling mounted. The antennas may be placed in each room, or area of use, in which telemetry is utilized, for example an X-ray room, examination room or operating room, or even in the equipment utilized. Since, in accordance with the present invention, the distance between a patient and the programmer no longer is a consideration with regard to signal reception, the programmer may be easily moved from one place to another without thereby affecting the signal quality. The placement of the antennas may also be optimized in advance, in consideration of where in the respective rooms the patient usually is located.
[0012] In accordance with an embodiment of the present invention the medical apparatus further has a control unit provided for measuring a signal quality parameter of signals received from the implantable medical device by each of the antenna devices. Thereafter one of the antenna devices is selected for subsequent reception or transmission of signals from the implantable medical device depending on the measured signal quality parameter of the received signals. Spatial diversity is thereby ensured, and the antenna giving the best reception may be chosen and a reliable communication is provided.
[0013] In accordance with another embodiment of the present invention the signal quality parameter is any of RSSI, BER, or C/N ratio. A flexibility in how to chose a suitable antenna, i.e. in dependence on an optional parameter, is thereby provided. These parameters are commonly known and often used in assessing signal quality, thus enabling the use of well established, easily obtainable algorithms.
[0014] In accordance with yet another embodiment of the present invention the control unit is utilized for measuring a signal quality parameter of signals received from the implantable medical device by each of the antenna devices at regular intervals, or continuously. It is thereby possible to rapidly detect a deteriorated signal quality and switch to an antenna having a better signal reception.
[0015] In accordance with yet another embodiment of the present invention the control unit is connected between the programmer or monitoring device and the antenna devices. In an alternative embodiment, the control unit is an integral part of the programmer. In yet a further embodiment, the control unit is provided as an integral part of either one of the antenna devices. This provides a modular structure, giving a great design flexibility, and enabling custom-made solutions.
[0016] In accordance with yet another embodiment of the present invention the communication links between the programmer or monitoring device and the control unit, and between the control unit and the antenna devices, may be via wire, e.g. an USB connection, or wirelessly, e.g. via Bluetooth. This again adds to the design flexibility.
[0017] In accordance with yet another embodiment of the present invention each of the antenna devices comprises a radio transceiver unit. In another embodiment, only one transceiver unit is provided, preferably centrally located in a room, or other area of use. Utilizing several radio transceiver units provides an additional security, but if a less expensive solution is desired, a fewer number of radio transceiver units may be provided.
[0018] In accordance with still another embodiment of the present invention each of the antenna devices are fixedly mounted, for example in a ceiling or to a wall. Thereby the antenna devices may be more or less permanently placed at locations considered to be the best in view of reception/transmission from and to an implantable medical device. The reception/transmission may be optimized in advance, in dependence of an expected location in a room of the patient wearing the implantable medical device.
[0019] In accordance with still another embodiment of the present invention each of the antenna devices comprises a conductive radiating antenna element, and these conductive radiating antenna elements are adapted to emit and receive radio waves having essentially parallel polarization Thereby spatial diversity is provided independently of polarization diversity.
[0020] In accordance with still another embodiment of the present invention each of the antenna devices comprises at least one conductive radiating antenna element capable of emitting and receiving radio waves of orthogonal polarizations. If at least two conductive radiating antenna elements are provided in each antenna device they should be operatively provided adjacent to each other at a single location in space.
[0021] In accordance with still another embodiment of the invention the programmer or monitoring device is portable, and is in particular a hand held device. In accordance with the present invention, the antenna devices are not physically part of the programmer or monitoring device, which would, considering the frequencies in question, require a certain, non-portable size of the programmer in order to accommodate the fastening of several antennas to it. The size of the programmer may therefore be reduced in accordance with the invention. A user may thereby easily bring the programmer along, should such need arise. In another embodiment, the programmer or monitoring device is arranged on a movable rack such as a roller table or the like, whereby the present invention may be utilized also in connection with currently used programmer or monitoring devices, providing a solution that is easy to implement with existing programmers.
[0022] The present invention is also related to such a system, in accordance with which advantages corresponding to the above described are achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a schematic block diagram of an exemplary embodiment of a medical apparatus in accordance with the present invention.
[0024] FIG. 2 is a schematic block diagram of another exemplary embodiment of a medical apparatus in accordance with the present invention.
[0025] FIG. 3 shows a system in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] In the following description the same reference numerals will be used for equivalent or similar elements throughout the drawings. With reference first to FIG. 1 , a schematic layout depicting an exemplary medical apparatus in accordance with the invention is shown. A medical apparatus 1 for programming and/or monitoring a patient related device 7 shown in FIG. 3 , for example an implantable medical device, over a radio-based wireless network comprises a programmer or monitoring device 2 , hereinafter referred to as a programmer 2 . The programmer 2 is provided with input and/or output means for transmitting programming instructions to an implantable medical device, and/or for outputting monitoring information patient related data, for example for display on a screen, thereby enabling a physician to easily see such patient related data received from the implantable medical device.
[0027] A control unit 3 , for example a microcontroller, is connected to the programmer 2 , via wired standards, for example via USB (Universal Serial Bus), or via some wireless protocols. Bluetooth is such an exemplary, preferred wireless protocol, being an open-standard protocol. Using an open-standard protocol allows interoperability among devices from different manufacturers, which may be very advantageous in some cases. For example, utilizing Bluetooth standard for communication between the programmer 2 and antenna devices may permit the use of programmers from different producers, without also necessitating antenna device changes, which is particularly advantageous if the antenna devices are wall mounted or in some other manner more permanently mounted. In the embodiment shown in FIG. 1 , the control unit 3 and the programmer 2 are shown as separate parts, but it is possible to, in an alternative embodiment, make the control unit 3 an integrated part of the programmer 2 .
[0028] The control unit 3 is connected to at least one radio frequency circuitry unit 4 , hereinafter called transceiver unit, via a digital link such as SPI (Serial Peripheral Interface), USB, Bluetooth or the like. The control unit 3 controls the one or more transceiver units 4 . The transceiver unit 4 embodies conventional radio frequency circuitry, such as, for example, a duplexer, connected to a transmitter section and a receiver section, microcontroller, a wakeup transmitter, switches, low noise amplifiers (LNA), power amplifiers, AGC (Automatic Gain Control), power detectors and filters. The transceiver unit may also be an integral part of the contol unit 3 .
[0029] The medical apparatus 1 further includes at least two antenna devices 5 a, 5 b, . . . , 5 n operatively provided at different locations, that is, they are provided as separate, stand alone units, i.e. not forming part of the programmer 2 as in the prior art. The programmer 2 is connected, via a control unit 3 and transceiver unit 4 , to the antenna devices 5 a, 5 b, . . . , 5 n and is provided for transmitting signals to and receiving signals from an implantable medical device via either one of the antenna devices 5 a, 5 b, . . . , 5 n. The connection between the antenna devices 5 a, 5 b, . . . , 5 n and the programmer 2 is a wired connection, e.g. an USB connection, or a wireless connection, e.g. via Bluetooth. Thereby movements of the programmer 2 are enabled, while the antenna devices 5 a, 5 b, . . . , 5 n are kept still, for example being permanently mounted to a wall or the like. By means of the invention it is possible to place the antenna devices 5 a, 5 b, . . . 5 n in an optimal way, preferably at stationary locations, such as for example wall mounted. The antenna devices 5 a, 5 b, . . . 5 n may be placed in each room, or area of use, in which telemetry is utilized, for example an X-ray room, examination room or operating room, or even in the equipment utilized. Since, in accordance with the present invention, the distance between a patient and the programmer 2 is not a consideration with regard to signal reception anymore, the programmer 2 may be easily moved from one place to another without the signal quality being affected. The placement of the antenna devices 5 a, 5 b, . . . 5 n may also be optimized in advance, in consideration of where in a respective room the patient usually is located. For example, in an X-ray room the patient is most likely placed at a certain location known in advance, and the antenna devices 5 a, 5 b , . . . , 5 n may be placed so as to optimize the reception/transmission in relation to this location. In the embodiment shown in FIG. 1 the antenna devices 5 a, 5 b, . . . , 5 n consist only of antenna elements, i.e. electrically conductive and radiating structures for transmitting and receiving radio frequency signals. These antenna elements can have any desired and appropriate shape, such as for example strip shape, cross shape or star shape. In the figure three such antenna elements are shown, but it is understood that any suitable number of antenna elements may be used. Further, each antenna device 5 a, 5 b , . . . , 5 n may comprise means for enabling polarization diversity, for example by providing the antenna device 5 a, . . . , 5 b , . . . 5 n with conductive structures for emitting and/or receiving radiation of different polarizations. In this regard, reference is made to the pending International application, no. PCT/SE2004/000832, entitled “Medical transceiver device and method”, having the same applicant as the present application. Its disclosure is incorporated herein by reference.
[0030] The antenna devices 5 a, 5 b, . . . , 5 n are connected to the transceiver unit 4 , the transceiver unit 4 being controlled by the control unit 3 . A switch device 6 , switchable between using one or more of the different antenna devices 5 a, 5 b , . . . , 5 n is also included. When utilizing spatial diversity, advantage is taken of the different paths of a wave propagation in a reflective environment, and the antenna device 5 a, 5 b, . . . , 5 n giving the best reception at any time may be utilized. In accordance with the invention thus, the antenna device 5 a, 5 b , . . . , 5 n giving the best communication link, as determined in a suitable way, is chosen for communication between the programmer 2 and an implantable medical device. The control unit 3 includes circuitry for measuring characteristics of the radio frequency signals as received by the antenna devices 5 a, 5 b , . . . , 5 n. Depending on a suitable signal quality indicator one of the antenna devices 5 a, 5 b, . . . , 5 n is chosen for the subsequent communication. The signal quality indicator or parameter may for example be one of: signal strength, bit error rate (BER), carrier-to-noise (C/N) ratio, carrier-to-interference (C/I) ratio or received signal strength indicators (RSSI). In an alternative embodiment, requiring more signal processing, the signals from two or more of the different antenna devices 5 a , 5 b , . . . , 5 n are combined, i.e. the different paths are put in phase and then added. It is possible to perform regular polling of all antenna devices 5 a , 5 b , . . . , 5 n or transceiver units 4 in order to keep track of the signal quality at different places in the room. In an alternative embodiment, the control unit is set on continuous listening of the antenna devices 5 a, 5 b , . . . , 5 n or transceiver units 4 .
[0031] Alternatively, the medical apparatus 1 , and in particular the control unit 3 thereof, receives from an implantable medical device a measure of a signal quality parameter of signals as received by the implantable medical device, wherein the signals received by the implantable medical device are signals as transmitted from the medical apparatus to the implantable medical device after having been distorted by a transmission medium, i.e. the air interface between the respective antenna devices. The signal strength and the phase of the signals thereafter transmitted may be altered in dependence on the signal quality parameter of the signals as received by the implantable medical device.
[0032] In FIG. 1 a single transceiver unit 4 is shown, but in an alternative embodiment, shown in FIG. 2 , several transceiver units 4 , 4 ′, 4 ″ could be used. In fact, each antenna device 5 a, 5 b , . . . , 5 n could include one or more antenna elements and one transceiver unit 4 , 4 ′, 4 ″. The antenna devices 5 a , 5 b, . . . , 5 n and their respective transceiver units 4 , 4 ′, 4 ″ could form an integrated unit, as shown in FIG. 2 , or be separated units. Utilizing several transceiver units enables the use of an ad-hoc structure, i.e. the antenna devices 5 a, 5 b , . . . 5 n, embodying antenna elements and a transceiver unit, constitutes autonomous nodes, thereby providing increased robustness in the communication.
[0033] In the embodiment of FIG. 2 , there is no need for a switch device 6 , since each antenna device 5 a, 5 b , . . . , 5 n comprises a transceiver unit 4 . In other respects, the embodiment of FIG. 2 is similar to the embodiment in FIG. 1 .
[0034] The number of antenna devices 5 a, 5 b, . . . , 5 n may be different in different rooms, in dependence of the particular need in a certain room. For example, an exercise room used for monitoring the heart of a patient when subject to an increased heart rate, may be provided with a larger number of antennas, thereby increasing the spatial diversity and enabling the patient to freely move around within the room without risking a communication failure due to fading. In a smaller room, in which the patient is not moving around, it may suffice to use a single antenna device 5 a, 5 b, . . . , 5 n.
[0035] In accordance with the invention, the placing of the antenna devices 5 a, 5 b, . . . , 5 n may be optimized with regard to, on the one hand, the most probable placement of the patient in a room. As was mentioned above, the most probable location of the patient in a room may be readily determined for example in an x-ray examination room, in which the patient presumably is monitored when being in situ for being x-rayed. The antennas may be mounted on the walls, the ceiling or even within equipment such as x-ray equipment or a hospital bed, or in a hospital room, such as a waiting room or an operating room. Thereby it is easy to optimize the communication between the patient-related device and the antennas of the medical apparatus in advance. In addition, when positioning the antenna devices 5 a, 5 b, . . . , 5 n one should also consider near-field interference, and in particular their mutual coupling. Mutual coupling is pronounced up to a few wavelengths, and requires the space between adjacent antennas to be no less than a half-wavelength, the distance thus depending on the frequency in question. The signal at antenna device locations spaced a few wavelengths apart are almost independent, so increasing the distance between antennas would be beneficial. In accordance with the state of the art, the antennas are mounted to the programmer, whereby the distance between the antennas is limited to the size of the programmer. In contrast to this, the programmer 2 in accordance with the invention may be made portable, and in particular hand-held. Since the antenna devices 5 a, 5 b, . . . , 5 n are not physically part of the casing containing the programmer 2 , i.e. not in physical contact with the programmer 2 , there are no restrictions being placed on the size of the programmer 2 for accommodating a plurality of antennas. Therefore the size of the programmer may be reduced considerably, and a user may easily bring the programmer 2 along if desired. In particular, the antenna devices 5 a , 5 b , . . . , 5 n may be placed at locations such that the distance between them is larger than the largest external length of the programmer, and also such that the antenna devices 5 a, 5 b , . . . , 5 n are separated at least two wavelengths apart in order to achieve appropriate spatial diversity. However, it is to be understood that the programmer 2 may, in an alternative embodiment, have a state-of-the art size and be arranged on a movable rack such as a roller table or the like.
[0036] In the prior art referred to in the introductory part of the description, the distance between the patient and the programmer is critical. In fact, as soon as the programmer, which includes antennas permanently mounted to it, is moved relative the patient the signal reception has to be assessed once more. In accordance with the invention, there is no longer a need for such tedious optimization.
[0037] Although the medical apparatus in accordance with the invention has been described above utilizing antenna devices separated from the programmer, it does not exclude the additional use of antennas mounted to the programmer.
[0038] FIG. 3 shows a system in accordance with the present invention. A medical apparatus 1 in accordance with the invention, comprising a programmer 2 , a control unit 3 , and antenna devices 5 a, 5 b , . . . , 5 n, with radio transceiver units 4 , 4 ′ . . . are utilized for monitoring and/or transmitting programming instructions to a patient related device 7 , here shown to be an implantable device, implanted into a patient 8 . The implantable medical device 7 has a radio transceiver enabled for communication with the medical apparatus 1 of the present invention.
[0039] Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventors to embody within the patent warranted heron all changes and modifications as reasonably and properly come within the scope of their contribution to the art. | A medical system includes an implantable medical device configured for implantation in a living subject to interact with the subject, an extracorporeal device having a processor that processes information such as programming instructions for the implantable medical device or monitoring data received from the implantable medical device, and at least two antenna devices located at respectively different locations. The implantable medical device communicates with at least one of the two antenna devices, and the extracorporeal device also communicates with the at least two antenna devices to exchange the aforementioned information with the implantable medical device via at least one of the two antenna devices. The at least two antenna devices are physically separated from the extracorporeal device and the extracorporeal device communicates with each of the at least two antenna devices via a communication link that allows the extracorporeal device to be freely moved relative to the at least two antenna devices. The communication link can be a hard-wired communication link or a wireless communication link. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a projection aligner (projection exposure apparatus) for performing and exposing so that a pattern drawn on a reticle is projected onto a wafer by light emitted from the light source.
2. Description of the Related Art
A projection aligner is used for manufacturing semiconductor devices. The projection aligner has a light source, a reticle stage with a reticle, a wafer stage with a wafer and a reduction lens(scale-down projection lens). During a projection exposure operation, a pattern on the reticle is projected onto the wafer via the reduction lens by light emitted from the light source.
Recently, the projection aligner is required to have a high-pattern position precision for coping with the latest devices. For increasing the pattern position precision, rising temperatures in the projection aligner by the light emitted from the light source, is not to be disregarded. Pattern position precision is affected by the heat expansion of the reticle or by the changing the distribution of distortion of the reduction lens.
SUMMARY OF THE INVENTION
An object of the present application is to improve the pattern position precision by stabilizing the temperature of the reticle or the reduction lens in the projection aligner.
To achieve the object of the invention, the invention provides a projection aligner comprising a reticle stage with a reticle placed thereon, a light source emitting a light for irradiating the reticle, a reduction lens arranged so that a pattern drawn on the reticle is projected onto a wafer by light emitted from the light source, and a temperature control unit controlling the temperature of the reticle or the reduction lens.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention, it is believed that the invention, the objects and features of the invention and further objects, features and advantages thereof will be better understood from the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a configurational view schematically showing a projection aligner according to a first embodiment of the present invention.
FIG. 2 ablock diagram showing the temperature control unit in FIG. 1.
FIG. 3 is a schematic side view showing, in an enlarged form neighborhood of the reticle shown in FIG. 1.
FIG. 4 is a schematic plane view of FIG. 3.
FIG. 5 is a configurational view schematically showing a projection aligner according to a second embodiment of the present invention.
FIG. 6 is a schematic side view showing, in an enlarged form, the neighborhood of the reticle shown in FIG. 5.
FIG. 7 is schematic plane view of FIG. 6.
FIG. 8 is a configurational view schematically showing a projection aligner according to a third embodiment of the present invention.
FIG. 9 is a schematic side view showing, in an enlarged form, the neighborhood of the reticle shown in FIG. 8.
FIG. 10 is a schematic plane view of FIG. 9.
FIG. 11 a block diagram showing the temperature control unit in FIG. 8.
FIG. 12 is a configurational view schematically showing a projection aligner according to a fourth embodiment of the present invention.
FIG. 13 is a schematic side view showing, in an enlarged form, the neighborhood of the reticle shown in FIG. 12.
FIG. 14 is a schematic plane view of FIG. 13.
FIG. 15 is a configurational view schematically showing a projection aligner according to a fifth embodiment of the present invention.
FIG. 16 is a schematic side view showing, in an enlarged form, the neighborhood of the reduction lens shown in FIG. 15.
FIG. 17 is a schematic plane view of FIG. 16.
FIG. 18 is a configurational view schematically showing a projection aligner according to a sixth embodiment of the present invention.
FIG. 19 is a schematic side view showing, in an enlarged form, the neighborhood of a reduction lens shown in FIG. 18.
FIG. 20 is a schematic plane view of FIG. 18.
FIG. 21 is a configurational view schematically showing a projection aligner according to a seventh embodiment of the present invention.
FIG. 22 is a schematic side view showing, in an enlarged form, the neighborhood of a reduction lens shown in FIG. 21.
FIG. 23 is a schematic plane view of FIG. 22. and;
FIG. 24 is a configurational view schematically showing a projection aligner according to a eighth embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will hereinafter be described in detail with reference to the accompanying drawings.
FIG. 1 is a configurational view schematically showing a projection aligner according to a first embodiment of the present invention.
In the first embodiment as shown in FIG. 1, an air-conditioning unit having a cooler 3, a heater 4, a air blower 5 and a ULPA (Ultra Low Penetration Air-filter) controls temperatures inside an environmental chamber 2 (environments around the projection aligner 1) and clears dust from the inside of the environmental chamber 2. Open arrows shown in FIG. 1 indicate flows of clean air within the environmental chamber 2.
As shown in FIG. 1, the projection aligner 1 according to the first embodiment has, for example, a light source 7 such as an ArF excimer laser or the like, a reticle stage 9 with a reticle (e.g., 4×(four-times) reticle) 8 placed thereon, a reduction lens 10, and a wafer stage and XY stage unit 12 with a wafer 11 placed thereon. Exposure is performed so that a pattern drawn on the reticle 8 is projected onto the wafer 11 by light emitted from the light source 7.
Further, the projection aligner 1 according to the first embodiment has a first temperature control unit (temperature control unit) 20 for directly applying clean air temperature-controlled to within a temperature, range of ±0.1°C. of a set temperature to the reticle 8 to thereby regulate or control the temperature of the reticle 8. The first temperature control unit 20 has a part 21 for supplying clean air subjected to temperature control and dust removal, an air-blowing part 22 for feeding the clean air to the inside of a casing or enclosure 1a of the projection aligner 1, and a discharge part 23 discharging the clean air passed through the periphery of the reticle 8 from the enclosure 1a of the projection aligner 1 and returning it to the supply part 21.
FIG. 2 is a block diagram showing the supply part 21. As shown in FIG. 2, the supply part 21 has a cooler 24, a heater 25, an air blower 26 and a ULPA filter 27. Further, the supply part 21 has a temperature sensor 28, a circuit 29 for driving the cooler 24 and the heater 25, and a circuit 30 for controlling both operations of the cooler 24 and the heater 25 based on a value detected by the temperature sensor 28. The control circuit 30 controls both operations of the cooler 24 and the heater 25 so that the temperature of the clean air discharged from the supply part 21 falls within ±0.1° C. of the set temperature. The reason why the temperature of the clean air is set within ±0.1° C. of the set temperature, is that since the position of a pattern on a 6-inch reticle is shifted by about 0.0281 μm when the reticle (whose effective area is 125 mm 2 ) is raised by 0.3° C. in temperature and this value makes up about 50% of a value (e.g., 0.05 μm or 0.06 μm) adopted as a reticle exposure device accuracy (overlay allowable accuracy) required for fabrication of ULSI, the remaining allowable error becomes extremely small. This is also because the temperature of the clean air is in an error range of temperatures set to the present practically-utilized temperature control unit. Incidentally, the set position of the temperature sensor 28 is not limited to the position illustrated in the drawing. This sensor 28 may also be located in the neighborhood of the reticle 8, for example.
FIG. 3 is a schematic side view showing, in an enlarged form, the neighborhood of the reticle shown in
FIG. 1. FIG. 4 is a schematic plane view of FIG. 3. The arrows in FIGS. 3 and 4 indicate flows of clean air. As shown in FIG. 1, 3 or 4, the air blowing part 22 has a piping 22a for feeding clean air delivered from the supply part 21 to the inside of the enclosure of the projection aligner 1, a manifold 22b coupled to the piping 22a, and a plurality of blow-off nozzles (blowing parts) 22c, which are formed at the leading end of the manifold 22b and discharge clean air to the surface (upper surface) on the light source 7 side, of the reticle 8. Reference numeral 13 indicates a pellicle attached to the reticle 8.
The discharge (intake) part 23 has a discharge port 23 a provided on the opposite side of the blow-off nozzles 22c with the reticle 8 interposed therebetween, and a piping 23 b for feeding back clean air to the supply part 21.
Upon projection exposure, as shown in FIGS. 3 and 4, the clean air controlled to within ±0.1° C. of the set temperature by the first temperature control unit 20 is directly applied over the entire upper surface (i.e., the side opposite to the pellicle surface and pattern surface) of the reticle 8 through the blow-off nozzles 22c so as to flow toward the discharge port 23 a along the upper surface of the reticle 8.
According to the projection aligner 1 of the first embodiment, as has been described above, the outer side of the enclosure 1a of the projection aligner 1 is temperature-controlled. Further, the clean air temperature-controlled to within ±0.1° C. of the set temperature by the first temperature control unit 20 is directly applied to the reticle 8 inside the enclosure 1a of the projection aligner 1. As a result, the temperature of the reticle 8 can be stabilized. Therefore, even when the 4× reticle is used or the reticle is increased in size, an error of a overlay accuracy within the reticle 8 is prevented and hence a ULSI subjected to patterning with a high-precision alignment accuracy is obtained. As a result, the yield of fabrication of the ULSI can be greatly improved. Since no pellicle exists on the upper surface of the reticle 8, a large cooling effect is obtained in the case of the present embodiment wherein the clean air has been applied onto the upper surface of the reticle 8.
FIG. 5 is a configurational view schematically showing a projection aligner according to a second embodiment of the present invention. FIG. 6 is a schematic side view illustrating, in an enlarged form, the neighborhood of the reticle shown in FIG. 5. FIG. 7 is a schematic plane view of FIG. 6.
In FIGS. 5 through 7, the same elements of structure as those shown in FIGS. 1 through 4 or the elements of structure corresponding to those shown in FIGS. 1 through 4 are identified by the same reference numerals. The projection aligner 30 according to the second embodiment is different from the projection aligner 1 according to the first embodiment only in that a cover (box) 31 for covering the outer sides of a reticle 8 and a reticle stage 9 is provided and blow-off nozzles 22d for allowing clean air to flow toward the side and lower surface of the reticle stage 9 are provided in addition to the blow-off nozzles 22c.
Upon projection exposure, as shown in FIGS. 6 and 7, clean air temperature-controlled to within ±0.1° C. of a set temperature by a first temperature control unit 20 is fed into the cover 31 through the blow-off nozzles 22c and the blow-off nozzles 22d and thereafter blown to a discharge port 23 a along the upper surface of the reticle 8 and the side and lower surface of the reticle stage 9.
According to the projection aligner 30 of the second embodiment, as has been described above, the cover 31 is provided and the blow-off nozzles 22d extending directly below the reticle 8 are also provided in addition to the blow-off nozzles 22c directed to the upper surface of the reticle 8. As a result, the temperature of the reticle stage 9 as well as both surfaces of the reticle 8 can be stabilized. Therefore, even when a 4× reticle is used or the reticle is increased in size, an error of a pattern position precision within the reticle 8 is prevented and hence a ULSI subjected to patterning with a high-precision alignment accuracy is obtained. As a result, the yield of production of the ULSI can be greatly improved.
FIG. 8 is a configurational view schematically showing a projection aligner according to a third embodiment of the present invention. FIG. 9 is a schematic side view illustrating, in an enlarged form, the neighborhood of a reticle. FIG. 10 is a schematic plane view of FIG. 9.
In FIGS. 8 through 10, the same elements of structure as those shown in FIGS. 1 through 4 or the elements of structure corresponding to those shown in FIGS. 1 through 4 are identified by the same reference numerals. The projection aligner 40 according to the third embodiment is different from the projection aligner 1 according to the first embodiment only in that a second temperature control unit 41 for controlling the temperature of a reticle 8 is provided. The second temperature control unit 41 has a cooling water supply part 42 and a piping 43 for allowing cooling water to flow.
FIG. 11 is a configurational view showing the supply part 42. As shown in FIG. 11, the supply part 42 has a cooler 44, a heater 45 and a pump 46. Further, the supply part 42 includes a temperature sensor 47, a circuit 48 for driving the cooler 44 and the heater 45, and a circuit 49 for controlling both operations of the cooler 44 and the heater 45 based on a value detected by the temperature sensor 47. The control circuit 49 controls both operations of the cooler 44 and the heater 45 so that cooling water discharged from the supply part 42 falls within ±0.1° C. of a set temperature. Incidentally, the set position of the temperature sensor 47 is not limited to the position illustrated in the drawing. This sensor may be located in the vicinity of a reticle stage 9, for example.
Upon projection exposure, as shown in FIGS. 9 and 10, clean air temperature-controlled to within ±0.1° C. of a set temperature by a first temperature control unit 20 is fed to the upper surface of the reticle 8 through blow-off nozzles 22c and discharged through a discharge port 23 a. Simultaneously with this, the cooling water temperature-controlled to within ±0.1° C. of the set temperature by the second temperature control unit 41 is caused to flow into the piping 43 to thereby cool the reticle stage 9.
According to the projection aligner 40 of the third embodiment, as has been described above, the upper surface of the reticle 8 is cooled by the clean air temperature-controlled to within ±0.1° C. of the set temperature. Further, the reticle stage 9 is cooled by the cooling water temperature-controlled to within ±0.1° C. of the set temperature. Therefore, the lower part (e.g., the four corners of the reticle, i.e., an area being in contact with the reticle stage 9) of the reticle 8 is also cooled by the reticle stage 9. Thus, even if the reticle 8 is irradiated with repetitive UV light or deep UV light (excimer laser beam) by the projection aligner 40, the reticle 8 is more effectively prevented from increasing in temperature. Therefore, since an error of a pattern position precision within the reticle 8 is prevented and a ULSI subjected to patterning with a high-precision alignment accuracy is obtained, the yield of fabrication of the ULSI can be greatly improved.
Since the piping 42 is wound on the side of the reticle stage 9, although the reticle 8 (with the pellicle) is automatically loaded onto and unloaded from the reticle stage 9, the piping 42 interferes with its loading and unloading.
FIG. 12 is a configurational view schematically showing a projection aligner according to a fourth embodiment of the present invention. FIG. 13 is a schematic side view illustrating, in an enlarged form, the neighborhood of a reticle shown in FIG. 12. FIG. 14 is a schematic plane view of FIG. 13.
In FIGS. 12 through 14, the same elements of structure as those shown in FIGS. 8 through 11 or the elements of structure corresponding to those shown in FIGS. 8 through 11 are identified by the same reference numerals. The projection aligner 50 according to the fourth embodiment is different from the projection aligner 40 according to the third embodiment only in that a cover (box) 31 for covering the outer sides of a reticle 8 and a reticle stage 9 is provided and blow-off nozzles 22d for allowing clean air to flow toward the lower surface and side of the reticle stage 9 are provided in addition to the blow-off nozzles 22c.
Upon projection exposure, as shown in FIGS. 13 and 14, clean air temperature-controlled to within ±0.1° C. of a set temperature by a first temperature control unit 20 is fed into the cover 31 through the blow-off nozzles 22c and the blow-off nozzles 22d and thereafter blown to a discharge port 23 a along the upper surface of the reticle 8 and the lower surface of the reticle stage 9. Simultaneously with this, cooling water temperature-controlled to within ±0.1° C. of a set temperature by a second temperature control unit 41 is caused to flow into a piping 42 to thereby cool the reticle stage 9.
According to the projection aligner 50 of the fourth embodiment, as has been described above, the upper and lower surfaces of the reticle 8 are cooled by the clean air temperature-controlled to within ±0.1° C. of the set temperature. Further, the reticle stage 9 is cooled by the cooling water temperature-controlled to within ±0.1° C. of the set temperature. Therefore, even if the reticle 8 is irradiated with repetitive UV light or deep UV light, the reticle 8 is more effectively blocked from rising in temperature. Therefore, since an error of a pattern position precision within the reticle 8 is prevented from occurring and a ULSI subjected to patterning with a high-precision alignment accuracy is obtained, the yield of production of the ULSI can be greatly improved.
FIG. 15 is a configurational view schematically showing a projection aligner according to a fifth embodiment of the present invention. FIG. 16 is a schematic side view showing, in an enlarged form, the neighborhood of a reticle shown in FIG. 15. FIG. 17 is a schematic plane view of FIG. 16.
In FIGS. 15 through 17, the same elements of structure as those shown in FIGS. 1 through 4 or the elements of structure corresponding to those shown in FIGS. 1 through 4 are identified by the same reference numerals. The projection aligner 60 according to the fifth embodiment is different from the projection aligner 1 according to the first embodiment only in that as an alternative to the first temperature control unit 20, there is provided a third temperature control unit 61 for applying gas temperature-controlled to within ±0.1° C. of a set temperature onto a reduction lens 10 to thereby adjust or control the temperature of the reduction lens 10.
The third temperature control unit 61 has a part 62 for supplying clean air subjected to temperature control and dust removal, a housing 63 for surrounding the scale-down lens 10 and a piping 64 for coupling the supply part 62 and the housing 63 to each other. Similarly to the first temperature control unit 20 shown in FIG. 2, the supply part 62 has a cooler 65, a heater 66, an air blower 67, a ULPA filter 68, a temperature sensor (not shown), a circuit (not shown) for driving the cooler 65 and the heater 66, and a circuit (not shown) for controlling the driving circuit in response to the output of the temperature sensor. Designated at numeral 69 in FIG. 16 is a reticle stage.
Upon projection exposure, as shown in FIGS. 16 and 17, clean air temperature-controlled to within ±0.1° C. of a set temperature by the third temperature control unit 61 is fed into the housing 63 so as to flow along the periphery of the reduction lens 10.
According to the projection aligner 60 of the fifth embodiment, as has been described above, since the reduction lens can be cooled by the clean air temperature-controlled to within ±0.1° C. of the set temperature, the reduction lens does not increase in temperature even if the reduction lens is irradiated with repetitive UV light or deep UV light by the projection aligner, and hence the distribution of distortion of the reduction lens remains unchanged. Therefore, a ULSI subjected to patterning with a high-precision alignment accuracy can be obtained and the yield of production of the ULSI can be greatly improved.
FIG. 18 is a configurational view schematically showing a projection aligner according to a sixth embodiment of the present invention. FIG. 19 is a schematic side view illustrating, in an enlarged form, the neighborhood of a reticle shown in FIG. 18. FIG. 20 is a schematic plane view of FIG. 19.
In FIGS. 18 through 20, the same elements of structure as those shown in FIGS. 1 through 4 or the elements of structure corresponding to those shown in FIGS. 1 through 4 are identified by the same reference numerals. The projection aligner 70 according to the sixth embodiment is different from the projection aligner 1 according to the first embodiment only in that as an alternative to the first temperature control unit 20, there is provided a fourth temperature control unit 71 for allowing cooling water temperature-controlled to within ±0.1° C. of a set temperature to flow around a reduction lens 10 to thereby adjust or control the temperature of the reduction lens 10.
The fourth temperature control unit 71 has a cooling water supply part 72, a cooling plate 73 for surrounding the reduction lens 10 and a piping 74 for spirally surrounding the periphery of the cooling plate 73. In a manner similar to the second temperature control unit 40 shown in FIG. 11, the supply part 72 has a cooler 75, a heater 76, a pump 77, a temperature sensor (not shown), a circuit (not shown) for driving the cooler 75 and the heater 76, and a circuit (not shown) for controlling the driving circuit in response to the output of the temperature sensor.
Upon projection exposure, as shown in FIGS. 19 and 20, the cooling water temperature-controlled to within ±0.1° C. of a set temperature by the fourth temperature control unit 71 is allowed to flow into the piping 74 to thereby control the temperature of the reduction lens 10.
According to the projection aligner 70 of the sixth embodiment, as has been described above, since the reduction lens 10 is cooled by the cooling water temperature-controlled to within ±0.1° C. of the set temperature, the reduction lens does not increase in temperature even if the reduction lens is irradiated with repetitive UV light or deep UV light by the projection aligner, and hence the distribution of distortion of the reduction lens remains unchanged. Therefore, a ULSI subjected to patterning with a high-precision alignment accuracy can be obtained and the yield of production of the ULSI can be greatly improved. Since the cooling using the cooling water is higher than the cooling using the clean air in cooling capacity, the yield of production thereof can be still further improved.
FIG. 21 is a configurational view schematically showing a projection aligner according to a seventh embodiment of the present invention. FIG. 22 is a schematic side view showing, in an enlarged form, the neighborhood of a reduction lens shown in FIG. 21. FIG. 22 is a schematic plane view of FIG. 21.
In FIGS. 21 through 23, the same elements of structure as those shown in FIGS. 18 through 20 or the elements of structure associated with those shown in FIGS. 18 through 20 are identified by the same reference numerals. The projection aligner 80 according to the seventh embodiment is different from that according to the sixth embodiment only in that the periphery of a reduction lens 10 in a fourth temperature control unit 71 is surrounded by a housing 81. Upon projection exposure, as shown in FIGS. 22 and 23, cooling water temperature-controlled to within ±0.1° C. of a set temperature by the fourth temperature control unit 71 is introduced into the housing 81 to control the temperature of the reduction lens 10.
According to the projection aligner 80 of the seventh embodiment, as has been described above, since the reduction lens 10 is cooled by the cooling water temperature-controlled to within ±0.1° C. of the set temperature, the reduction lens does not increase in temperature even if the reduction lens is irradiated with repetitive UV light or deep UV light by the projection aligner, and hence the distribution of distortion of the reduction lens remains unchanged. Therefore, a ULSI subjected to patterning with a high-precision alignment accuracy can be obtained and the yield of production of the ULSI can be greatly improved. Since the cooling using the cooling water is higher than the cooling using the clean air in cooling capacity, the yield of production thereof can be still further improved.
FIG. 24 is a configurational view schematically showing a projection aligner according to an eighth embodiment of the present invention.
The projection aligner 90 according to the eighth embodiment is different from the projection aligner 1 according to the first embodiment only in that the projection aligner 90 combines the first temperature control unit 20 shown in FIG. 1 with the third temperature control unit 61 shown in FIG. 15.
Since both a reticle 8 and a reduction lens 10 are temperature-controlled (normally cooled) to within ±0.1° C. of a set temperature in the projection aligner 90 according to the eighth embodiment, a ULSI subjected to patterning with a higher-precision alignment accuracy as compared with where only the reticle is temperature-controlled or where only the reduction lens is temperature-controlled, is obtained. Therefore, the yield of fabrication of the ULSI can be greatly improved.
Further, the combination of the temperature control unit for the reticle 8 and the temperature control unit for the reduction lens 10 is not limited to the above. For example, any of the reticle temperature control units shown in FIGS. 1, 5, 8 and 12 may be combined with any of the lens temperature control units shown in FIGS. 15, 18 and 21.
While the present invention has been described with reference to the 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 those skilled in the art on 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. | An object of a inventions of the present application is raising the pattern position precision by stabilizing the temperature of a reticle or a reduction lens in a projection aligner. The projection aligner comprises a reticle stage with a reticle, a light source emitting light to the reticle, a reduction lens projecting the light onto the wafer via the reticle, and a temperature control unit controlling the temperature of the reticle or/and a reduction lens by a clean air. | 6 |
This application claims the benefit of Ser. No. 60/222,687, filed Aug. 2, 2000.
FIELD OF THE INVENTION
The present invention relates generally to storage bags and more specifically to worksite storage bags designed to hold and protect various tools and accessories.
BACKGROUND
It is known in the art to produce a bag that is required to carry substantial loads for various situations. These bags have numerous designs for various specific functions. However, these designs fail to address many concerns for a bag in use at a construction site.
Generally, many prior bag designs are made out of a unitary material that creates an enclosure. These bags, though good for light loads, are not well suited for carrying larger loads that require a great deal of strength. However, disclosures such as U.S. Pat. No. 5,518,315 disclose a frame attached to the bottom of a bag. This frame, though providing some support to the bottom of the bag, does not disclose a device that would provide superior protection to destruction of items in a bag and protect items from moisture damage.
Furthermore, the handles of bags are generally left to simply sitting on the outside walls of the bag, this can reduce the durability of the handles and the ability to carry extremely heavy loads. However, it is desirous to more integrally associate the handles with the bag. Handles that are simply affixed to the walls of the bag pose the possibility of tearing lose.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a handle system for a bag that may carry a heavy load without breaking or tearing away from the bag to which the handles are attached.
It is another object of the present invention to provide a storage bag which is large and strong enough to carry heavy loads.
A third object of the present invention is to provide a bag with a storage compartment reinforced with a base portion that is both durable and resistant to the elements such as water.
Yet another object of the present invention is to provide a storage bag that has additional storage pockets such that the seems of the pockets are resistant to wear due to grinding from debris and dirt within the pocket.
The present invention is a heavy-duty storage bag, especially for use at a construction work site. The present invention discloses a handle and strap system that surrounds the entire bag allowing for even weight distribution and long term durability. Furthermore, the bag is provided with pockets that are of a heavy-duty construction and affixed to the bag in such a way as to create a distance from the bottom of the pocket thus reducing wear due to debris. Another embodiment of the present invention provides a bottom for a bag that is both durable and resilient to elements such as moisture.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
FIG. 1 is a perspective view of the tool storage bag according to the present invention;
FIG. 2 is an end view of the tool storage bag according to the present invention;
FIG. 3 is a plan view of the interior of the tool storage bag according to the present invention including a cross-sectional view of side pockets of the worksite storage bag according to the present invention;
FIG. 4 is a cross-sectional view taken along line 4 — 4 of FIG. 3;
FIG. 5 is a bottom view of the tool storage bag according to the present invention;
FIG. 6 is a plan view of a front of a worksite storage bag according to an alternate embodiment of the present invention;
FIG. 7 is a plan view of a side of a worksite storage bag according to an alternate embodiment of the present invention; and
FIG. 8 is a perspective view of a tray bottom of a worksite storage bag according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A tool storage bag 10 , as is illustrated in FIGS. 1-5, includes a base 12 and generally vertical sidewalls 14 A- 14 D which are formed of a ballistic nylon inner and outer shell having open cell urethane disposed therebetween. A cover 16 is attached to the sidewall 14 D by a fabric hinge. A zipper 18 is provided along sidewalls 14 A- 14 C for securing the cover 16 in a closed position. The tool storage bag 10 is designed for storing tools and accessories and includes a plurality of exterior pockets 20 disposed on the exterior surface and an additional plurality of interior pockets 22 (as shown in FIG. 3) disposed on an interior surface of the sidewalls 14 A- 14 D. The pockets 20 , 22 are formed through stitching material to the sidewalls 14 A- 14 D. The sidewalls 14 A- 14 D are spaced a distance apart so as to create a large footprint for the tool storage bag 10 . This large footprint allows for the storage of numerous tools of various sizes not currently accommodated by other storage bags. Furthermore, the pockets 20 , 22 allow for additional storage of tools and their attendant accessories.
With continuing reference to FIG. 1 and additional reference to FIGS. 2-3, the tool storage bag 10 additionally includes a first leather strap portion 25 that extends along sidewall 14 A, the base 12 and sidewall 14 D. The first leather strap 25 terminates in uniquely designed handles 26 a, 26 b, described below. A second leather strap 28 extends from sidewall 14 B, the base 12 and sidewall 14 C and crossing the first leather strap 25 on the base 12 . The second leather strap 28 terminates at both ends in metal loops 29 which are designed to be engaged by a shoulder strap (not shown). The ends of leather straps 25 , 28 are stitched to the sidewalls 14 A- 14 D by a boxstitch 30 and to the base 12 of the storage bag 10 . Furthermore, the leather straps 25 , 28 provide even weight distribution for ease of transport and storage. The leather straps 25 , 28 in traversing, as one piece, the entire distance along the sidewalls and base of the storage bag 10 ensure that the weight of the storage bag 10 is not shifted unevenly.
With continuing reference to FIG. 1 and particular reference to FIG. 2 the unique handles 26 a, 26 b may be seen. The handles 26 a, 26 b have hook-and-loop fasteners 27 a, 27 b on the innermost sides for attaching the handles 26 a, 26 b together when carrying or storing the worksite storage bag 10 . The handles 26 a, 26 b may be fastened together to allow ease of storage and transport. Furthermore, having the handles 26 a, 26 b secured on top of the tool storage bag 10 can increase safety at a work site and during transport.
Now turning particular reference to FIGS. 3 and 4, the inner pockets 20 and exterior pockets 22 which are sewn to the inner and outer surfaces of the sidewalls 14 A- 14 D can be seen in detail. The pockets 20 , 22 are disposed around the interior and exterior of the tool storage bag 10 . The plurality of pockets 20 , 22 allow for extreme flexibility in storage of items and for increased storage capacity. The pockets 20 , 22 are provided with a lower seam 21 which is spaced a distance D above the pocket bottom 20 a, 22 a. This distance D up the sidewalls 14 A- 14 D will allow sand and other grit to fall to the pocket bottom 20 a, 22 a and not affect the seam 21 . In not affecting the seam 21 the seam 21 may have a longer wear life and increased value to the consumer.
With reference to FIGS. 6-8 an alternate embodiment of the tool storage bag 110 is provided with a plastic bottom or tray 60 which is sewn to the sidewalls 14 A- 14 D. The storage bag 110 as indicated in FIGS. 6 and 7 is disposed within the tray 60 . Thus the storage bag 110 includes a base and sidewalls 114 A- 114 D that extend to the bottom of the tray 60 . The tray 60 is provided with recesses 64 for receiving the first leather strap 125 and further recesses 62 for receiving the second leather strap 128 . The tray 60 receives the bottom of the storage bag 110 providing increased stability and increased wear resistance to the bottom of the storage bag 110 . Furthermore, the tray 60 is constructed of a suitable plastic or rubber which will also resist dampness which may be present at several worksites. This resistance to dampness will help increase the lifetime of tools stored in the storage bag 110 by resisting corrosion that may occur due to dampness that would otherwise soak through the storage bag 110 .
Now turning with particular reference to FIG. 8, the recesses 62 and 64 which receive the first leather strap 125 and the second leather strap 128 allow for a close fit of the leather straps 125 , 128 . This ensures that the leather traps 125 , 128 will not lose their grip on the storage bag 110 as it is moved from location to location. Furthermore, the recesses 62 , 64 may increase the wear time of the straps as well removing sharp edges which may be exposed if the leather straps 125 , 128 were not allowed to recess under the storage bag 10 . The tray 60 also includes a plurality of openings 66 a - 66 d and 68 a - 68 b which are formed to receive the leather straps 125 , 128 . The first leather strap 125 is received first through opening 66 a, extends across the bottom of the tray 60 , then under the bottom channel 74 through opening 66 b, then back through opening 66 c across the bottom of the tray 60 , and finally exiting the tray 60 through opening 66 d where it extends upward along the sidewall of the tray. In this way the first leather strap 25 travels from the outside of the tray into the tray 60 and exits the tray again. This serpentine path ensures that the first leather strap 125 will never disengage the tray 60 thus further assuring that the storage bag 110 is securely held by the first leather strap 125 . The second leather strap 128 is received first by opening 68 a extends below the channel 74 , while also being received into the channel 74 , crossing the first leather strap 125 and then is received by opening 68 b. In this manner the second leather strap 128 is disposed on the inside and the outside of the tray 60 as well further ensuring a secure hold upon the tray 60 and the tool storage bag 110 .
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | A tool storage bag is provided for storing tools and accessories at a work site. The tool storage bag has straps that allow for even distribution of the load during transit. The bag also includes a wear-resistant pocket design and a reinforced bottom construction. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 12/828,629, filed Jul. 1, 2010, which is a continuation of U.S. application Ser. No. 12/428,287 (now U.S. Pat. No. 7,757,692—issued Jul. 20, 2010), filed Apr. 22, 2009, which is a continuation of U.S. application Ser. No. 10/847,554, filed May 17, 2004, which is a divisional of U.S. application Ser. No. 09/951,105, filed Sep. 11, 2001, each of which is hereby incorporated herein by reference in its entirety. Any and all priority claims identified in the Application Data Sheet, or any correction thereto, are hereby incorporated by reference under 37 CFR 1.57.
BACKGROUND OF THE INVENTION
[0002] The present invention is generally directed to a treatment of Chronic Obstructive Pulmonary Disease (COPD). The present invention is more particularly directed to removable air passageway obstruction devices, and systems and methods for removing the devices.
[0003] Chronic Obstructive Pulmonary Disease (COPD) has become a major cause of morbidity and mortality in the United States over the last three decades. COPD is characterized by the presence of airflow obstruction due to chronic bronchitis or emphysema. The airflow obstruction in COPD is due largely to structural abnormalities in the smaller airways. Important causes are inflammation, fibrosis, goblet cell metaplasia, and smooth muscle hypertrophy in terminal bronchioles.
[0004] The incidence, prevalence, and health-related costs of COPD are on the rise. Mortality due to COPD is also on the rise. In 1991 COPD was the fourth leading cause of death in the United States and had increased 33% since 1979.
[0005] COPD affects the patients whole life. It has three main symptoms: cough; breathlessness; and wheeze. At first, breathlessness may be noticed when running for a bus, digging in the garden, or walking up hill. Later, it may be noticed when simply walking in the kitchen. Over time, it may occur with less and less effort until it is present all of the time.
[0006] COPD is a progressive disease and currently has no cure. Current treatments for COPD include the prevention of further respiratory damage, pharmacotherapy, and surgery. Each is discussed below.
[0007] The prevention of further respiratory damage entails the adoption of a healthy lifestyle. Smoking cessation is believed to be the single most important therapeutic intervention. However, regular exercise and weight control are also important. Patients whose symptoms restrict their daily activities or who otherwise have an impaired quality of life may require a pulmonary rehabilitation program including ventilatory muscle training and breathing retraining. Long-term oxygen therapy may also become necessary.
[0008] Pharmacotherapy may include bronchodilator therapy to open up the airways as much as possible or inhaled .beta.-agonists. For those patients who respond poorly to the foregoing or who have persistent symptoms, Ipratropium bromide may be indicated. Further, courses of steroids, such as corticosteroids, may be required. Lastly, antibiotics may be required to prevent infections and influenza and pheumococcal vaccines may be routinely administered. Unfortunately, there is no evidence that early, regular use of pharmacotherapy will alter the progression of COPD.
[0009] About 40 years ago, it was first postulated that the tethering force that tends to keep the intrathoracic airways open was lost in emphysema and that by surgically removing the most affected parts of the lungs, the force could be partially restored. Although the surgery was deemed promising, the procedure was abandoned.
[0010] The lung volume reduction surgery (LVRS) was later revived. In the early 1990's, hundreds of patients underwent the procedure. However, the procedure has fallen out of favor due to the fact that Medicare stopping reimbursing for LVRS. Unfortunately, data is relatively scarce and many factors conspire to make what data exists difficult to interpret. The procedure is currently under review in a controlled clinical trial. What data does exist tends to indicate that patients benefited from the procedure in terms of an increase in forced expiratory volume, a decrease in total lung capacity, and a significant improvement in lung function, dyspnea, and quality of life. However, the surgery is not without potential complications. Lung tissue is very thin and fragile. Hence, it is difficult to suture after sectioning. This gives rise to potential infection and air leaks. In fact, nearly thirty percent (30%) of such surgeries result in air leaks.
[0011] Improvements in pulmonary function after LVRS have been attributed to at least four possible mechanisms. These include enhanced elastic recoil, correction of ventilation/perfusion mismatch, improved efficiency of respiratory muscaulature, and improved right ventricular filling.
[0012] Lastly, lung transplantation is also an option. Today, COPD is the most common diagnosis for which lung transplantation is considered. Unfortunately, this consideration is given for only those with advanced COPD. Given the limited availability of donor organs, lung transplant is far from being available to all patients.
[0013] In view of the need in the art for new and improved therapies for COPD which provide more permanent results than pharmacotherapy while being less invasive and traumatic than LVRS, at least two new therapies have recently been proposed.
[0014] Both of these new therapies provide lung size reduction by permanently collapsing at least a portion of a lung.
[0015] In accordance with a first one of these therapies, and as described in U.S. Pat. No. 6,258,100 assigned to the assignee of the present invention and incorporated herein by reference, a lung may be collapsed by obstructing an air passageway communicating with the lung portion to be collapsed. The air passageway may be obstructed by placing an obstructing member in the air passageway. The obstructing member may be a plug-like device which precludes air flow in both directions or a one-way valve which permits air to be exhaled from the lung portion to be collapsed while precluding air from being inhaled into the lung portion. Once the air passageway is sealed, the residual air within the lung will be absorbed over time to cause the lung portion to collapse.
[0016] As further described in U.S. Pat. No. 6,258,100, the lung portion may be collapsed by inserting a conduit into the air passageway communicating with the lung portion to be collapsed. An obstruction device, such as a one-way valve is then advanced down the conduit into the air passageway. The obstruction device is then deployed in the air passageway for sealing the air passageway and causing the lung portion to be collapsed.
[0017] The second therapy is fully described in copending U.S. application Ser. No. 09/534,244, filed Mar. 23, 2000, for LUNG CONSTRICTION APPARATUS AND METHOD and, is also assigned to the assignee of the present invention. As described therein, a lung constriction device including a sleeve of elastic material is configured to cover at least a portion of a lung. The sleeve has a pair of opened ends to permit the lung portion to be drawn into the sleeve. Once drawn therein, the lung portion is constricted by the sleeve to reduce the size of the lung portion.
[0018] Both therapies hold great promise for treating COPD. Neither therapy requires sectioning and suturing of lung tissue.
[0019] While either therapy alone would be effective in providing lung size reduction and treatment of COPD, it has recently been proposed that the therapies may be combined for more effective treatment. More specifically, it has been proposed that the therapies could be administered in series, with the first mentioned therapy first applied acutely for evaluation of the effectiveness of lung size reduction in a patient and which lung portions should be reduced in size to obtain the best results. The first therapy is ideal for this as it is noninvasive and could be administered in a physician's office. Once the effectiveness of lung size reduction is confirmed and the identity of the lung portions to be collapsed is determined, the more invasive second mentioned therapy may be administered.
[0020] In order to combine these therapies, or simply administer the first therapy for evaluation, it will be necessary for at least some of the deployed air passageway obstruction devices to be removable. Unfortunately, such devices as currently known in the art are not suited for removal. While such devices are expandable for permanent deployment, such devices are not configured or adapted for recollapse after having once been deployed in an air passageway to facilitate removal. Hence, there is a need in the art for air passageway obstruction devices which are removable after having been deployed and systems and methods for removing them.
SUMMARY OF THE INVENTION
[0021] The invention provides device for reducing the size of a lung comprising an obstructing structure dimensioned for insertion into an air passageway communicating with a portion of the lung to be reduced in size, the obstructing structure having an outer dimension which is so dimensioned when deployed in the air passageway to preclude air from flowing into the lung portion to collapse the portion of the lung for reducing the size of the lung, the obstructing structure being collapsible to permit removal of the obstruction device from the air passageway.
[0022] The invention further provides an assembly comprising a device for reducing the size of a lung, the device being dimensioned for insertion into an air passageway communicating with a portion of the lung to be reduced in size, the device having an outer dimension which is so dimensioned when deployed in the air passageway to preclude air from flowing into the lung portion to collapse the portion of the lung for reducing the size of the lung, a catheter having an internal lumen and being configured to be passed down a trachea, into the air passageway, and a retractor dimensioned to be passed down the internal lumen of the catheter, seizing the device, and pulling the obstruction device proximally into the internal lumen to remove the device from the air passageway. The device is collapsible after having been deployed to permit the device to be pulled proximally into the internal lumen of the catheter by the retractor.
[0023] The invention further provides a method of removing a deployed air passageway obstruction device from an air passageway in which the device is deployed. The method includes the steps of passing a catheter, having an internal lumen, down a trachea and into the air passageway, advancing a retractor down the internal lumen of the catheter to the device, seizing the device with the retractor, collapsing the device to free the device from deployment in the air passageway, and pulling the device with the retractor proximally into the internal lumen of the catheter.
[0024] The invention still further provides an air passageway obstruction device comprising a frame structure, and a flexible membrane overlying the frame structure. The frame structure is collapsible upon advancement of the device into the air passageway, expandable into a rigid structure upon deployment in the air passageway whereby the flexible membrane obstructs inhaled air flow into a lung portion communicating with the air passageway, and re-collapsible upon removal from the air passageway.
[0025] The invention still further provides an air passageway obstruction device comprising frame means for forming a support structure, and flexible membrane means overlying the support structure. The frame means is expandable to an expanded state within an air passageway to position the membrane means for obstructing air flow within the air passageway and is collapsible for removal of the device from the air passageway.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further objects and advantages thereof, may best be understood by making reference to the following description taken in conjunction with the accompanying drawings, in the several figures of which like referenced numerals identify identical elements, and wherein:
[0027] FIG. 1 is a simplified sectional view of a thorax illustrating a healthy respiratory system;
[0028] FIG. 2 is a sectional view similar to FIG. 1 but illustrating a respiratory system suffering from COPD and the execution of a first step in treating the COPD condition in accordance with the present invention;
[0029] FIG. 3 is a perspective view, illustrating the frame structure of a removable air passageway obstruction device embodying the present invention;
[0030] FIG. 4 is a perspective view of the complete air passageway obstruction device of FIG. 3 ;
[0031] FIG. 5 is an end view of the device of FIG. 3 illustrating its operation for obstructing inhaled air flow;
[0032] FIG. 6 is another end view of the device of FIG. 3 illustrating its operation for permitting exhaled air flow;
[0033] FIG. 7 is a perspective view of the device of FIG. 3 , illustrating its operation for permitting partial exhaled air flow;
[0034] FIG. 8 is a side view illustrating a first step in removing the device of FIG. 3 in accordance with one embodiment of the present invention;
[0035] FIG. 9 is another side view illustrating the collapse of the device of FIG. 3 as it is removed from an air passageway;
[0036] FIG. 10 is a side view illustrating an initial step in the removal of the device of FIG. 3 in accordance with another embodiment of the present invention;
[0037] FIG. 11 is a side view illustrating engagement of the frame structure of the device with a catheter during removal of the device;
[0038] FIG. 12 is a side view illustrating the collapse of the device by the catheter during removal of the device;
[0039] FIG. 13 is a side view of another air passageway obstruction device embodying the present invention during an initial step in its removal from an air passageway;
[0040] FIG. 14 is another side view of the device of FIG. 13 illustrating its collapse during removal from the air passageway;
[0041] FIG. 15 is a perspective view of the frame structure of another removable air passageway obstruction device embodying the present invention;
[0042] FIG. 16 is a cross-sectional side view of the device of FIG. 15 shown in a deployed state;
[0043] FIG. 17 is a perspective side view of the device of FIG. 15 shown in a deployed state;
[0044] FIG. 18 is a side view illustrating an initial step in removing the device of FIG. 15 from an air passageway;
[0045] FIG. 19 is a side view illustrating an intermediate step in the removal of the device of FIG. 15 ; and
[0046] FIG. 20 is a side view illustrating the collapse of the device of FIG. 15 during its removal from an air passageway.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] Referring now to FIG. 1 , it is a sectional view of a healthy respiratory system. The respiratory system 20 resides within the thorax 22 which occupies a space defined by the chest wall 24 and the diaphragm 26 .
[0048] The respiratory system 20 includes the trachea 28 , the left mainstem bronchus 30 , the right mainstem bronchus 32 , the bronchial branches 34 , 36 , 38 , 40 , and 42 and sub-branches 44 , 46 , 48 , and 50 . The respiratory system 20 further includes left lung lobes 52 and 54 and right lung lobes 56 , 58 , and 60 . Each bronchial branch and sub-branch communicates with a respective different portion of a lung lobe, either the entire lung lobe or a portion thereof. As used herein, the term “air passageway” is meant to denote either a bronchial branch or sub-branch which communicates with a corresponding individual lung lobe or lung lobe portion to provide inhaled air thereto or conduct exhaled air therefrom.
[0049] Characteristic of a healthy respiratory system is the arched or inwardly arcuate diaphragm 26 . As the individual inhales, the diaphragm 26 straightens to increase the volume of the thorax 22 . This causes a negative pressure within the thorax. The negative pressure within the thorax in turn causes the lung lobes to fill with air. When the individual exhales, the diaphragm returns to its original arched condition to decrease the volume of the thorax. The decreased volume of the thorax causes a positive pressure within the thorax which in turn causes exhalation of the lung lobes.
[0050] In contrast to the healthy respiratory system of FIG. 1 , FIG. 2 illustrates a respiratory system suffering from COPD. Here it may be seen that the lung lobes 52 , 54 , 56 , 58 , and 60 are enlarged and that the diaphragm 26 is not arched but substantially straight. Hence, this individual is incapable of breathing normally by moving the diaphragm 28 . Instead, in order to create the negative pressure in the thorax 22 required for breathing, this individual must move the chest wall outwardly to increase the volume of the thorax. This results in inefficient breathing causing these individuals to breathe rapidly with shallow breaths. It has been found that the apex portion 62 and 66 of the upper lung lobes 52 and 56 , respectively, are most affected by COPD.
[0051] In accordance with this embodiment of the present invention, COPD treatment or evaluation is initiated by feeding a conduit or catheter 70 down the trachea 28 , into a mainstream bronchus such as the right mainstem bronchus 32 , and into an air passageway such as the bronchial branch 42 or the bronchial sub-branch 50 . An air passageway obstruction device embodying the present invention is then advanced down an internal lumen 71 of the catheter 70 for deployment in the air passageway. Once deployed, the obstruction device precludes inhaled air from entering the lung portion to be collapsed. In accordance with the present invention, it is preferable that the obstruction device take the form of a one-way valve. In addition to precluding inhaled air from entering the lung portion, the device further allows air within the lung portion to be exhaled. This results in more rapid collapse of the lung portion. However, obstruction devices which preclude both inhaled and exhaled air flow are contemplated as falling within the scope of the invention.
[0052] The catheter 70 is preferably formed of flexible material such as polyethylene. Also, the catheter 70 is preferably preformed with a bend 72 to assist the feeding of the catheter from the right mainstem bronchus 32 into the bronchial branch 42 .
[0053] FIGS. 3 and 4 show an air passageway obstruction device 80 embodying the present invention. The device 80 includes a proximal end 82 and a distal end 84 . The device 80 further includes a frame structure 86 including frame supports 88 , 90 , and 92 .
[0054] Each of the frame supports has a shape to define a generally cylindrical center portion 94 and a pair of oppositely extending inwardly arcuate conical end portions 96 and 98 . The frame structure further includes a plurality of fixation members 100 , 102 , and 104 which extend distally from the proximal end 82 . The fixation members have the generally conical shape and terminate in fixation projections or anchors 106 , 108 , and 110 which extend radially outwardly.
[0055] Overlying and partially enclosing the frame structure 86 is a flexible membrane 112 . The flexible membrane extends over the generally cylindrical and conical portions 94 and 98 defined by the frame structure. Hence, the flexible membrane is opened in the proximal direction.
[0056] The flexible membrane may be formed of silicone or polyurethane, for example. It may be secured to the frame structure in a manner known in the art such as by crimping, riveting, or adhesion.
[0057] The frame structure 86 and the device 80 are illustrated in FIGS. 3 and 4 as the device would appear when fully deployed in an air passageway. The frame structure supports and frame structure fixation members are preferably formed of stainless steel or Nitinol or other suitable material which has memory of an original shape. The frame structure permits the device to be collapsed for advancement down the internal lumen 71 of the catheter 70 into the air passageway where the device is to be deployed. Once the point of deployment is reached, the device is expelled from the catheter to assume its original shape in the air passageway. In doing so, the generally cylindrical portion 94 contacts the inner wall of the air passageway and the fixation projections 106 , 108 , and 110 pierce the wall of the air passageway for fixing or anchoring the device 80 within the air passageway.
[0058] When the device 80 is deployed, the frame structure 86 and flexible membrane 112 form an obstructing structure or one-way valve. FIGS. 5 and 6 show the valve action of the device 80 when deployed in an air passageway, such as the bronchial branch 42 .
[0059] As shown in FIG. 5 , during inhalation, the flexible membrane is filled with air and expands outwardly to obstruct the air passageway 42 . This precludes air from entering the lung portion being collapsed. However, as shown in FIG. 6 , during expiration, the flexible membrane 112 deflects inwardly to only partially obstruct the air passageway 42 . This enables air, which may be in the lung portion being collapsed, to be exhaled for more rapid collapse of the lung portion. FIG. 7 is another view showing the device 80 during expiration with a portion 114 of the membrane 112 deflected inwardly.
[0060] FIGS. 8 and 9 illustrate a manner in which the device 80 may be removed from the air passageway 42 in accordance with one embodiment of the present invention. As previously mentioned, it may be desired to remove the device 80 if it is only used for evaluating the effectiveness of collapsing a lung portion or if it is found the more effective treatment may be had with the collapse of other lung portions.
[0061] The device 80 is shown in FIG. 8 in a fully deployed state. The catheter 70 having the internal lumen 71 is advanced to the proximal end of the device 80 . In FIG. 8 it may be noted that the fixation members 102 and 104 define a larger conical radius than the frame supports 88 and 90 . Hence, when the proximal end of the device is engaged by a retractor and the catheter 70 is moved distally as shown in FIG. 9 , the internal lumen of the catheter engages the fixation members 102 and 104 before it engages the frame supports 88 and 90 . This causes the fixation projections to first disengage the inner wall of the air passageway 42 . With the device now free of the air passageway side wall, the retractor may be used to pull the device into the internal lumen 71 of the catheter 70 causing the support structure and thus the device to collapse. The collapsed device may now fully enter the internal lumen of the catheter for removal.
[0062] FIGS. 10-12 show another embodiment of the present invention for removing the device 80 from the air passageway 42 . Here, the catheter 70 is fed down a bronchoscope 118 to the device 80 . The retractor takes the form of a forceps 120 .
[0063] In FIG. 10 it may be seen that the forceps has just engaged the proximal end 82 of the device 80 . In FIG. 11 the forceps 120 is held stationary while the catheter 70 is advanced distally so that the internal lumen 71 of the catheter 70 engages the fixation members 102 and 104 . Further advancement of the catheter 70 as seen in FIG. 12 deflects the fixation projections 110 and 108 inwardly away from the inner wall of the air passageway 42 . Now, the forceps may be used to pull the device 80 into the internal lumen 71 of the catheter 70 for removal of the device 80 from the air passageway 42 .
[0064] FIGS. 13 and 14 show another removable air passageway obstruction device 130 and a method of removing it from an air passageway in accordance with the present invention. The device 130 is shown in FIG. 13 deployed in the air passageway 42 and the catheter 70 is in ready position to remove the device 130 from the air passageway 42 .
[0065] The device 130 is of similar configuration to the device 80 previously described. Here however, the fixation members 136 and 138 are extensions of the frame supports 132 and 134 , respectively. To that end, it will be noted in FIG. 13 that the frame supports 132 and 134 cross at a pivot point 140 at the distal end 142 of the device 130 . They extend distally and then are turned back at an acute angle to terminate at fixation or anchor ends 146 and 148 . When the device is deployed as shown in FIG. 13 , the cylindrical portions of the support frame engage the inner wall of the air passageway 42 and the fixation points 146 and 148 project into the inner wall of the air passageway 42 to maintain the device in a fixed position. The flexible membrane 150 extends from the dashed line 152 to the pivot or crossing point 140 of the frame supports 132 and 134 to form a one-way valve.
[0066] When the device is to be removed, the frame structure of the device 130 is held stationary by a retractor within the catheter 70 and the catheter is advanced distally. When the catheter 70 engages the frame supports 132 and 134 , the frame supports are deflected inwardly from their dashed line positions to their solid line positions. This also causes the fixation members 136 and 138 to be deflected inwardly from their dashed line positions to their solid line positions in the direction of arrows 154 . These actions disengage the device 130 from the inner wall of the air passageway 42 . Now, the retractor may pull the device into the internal lumen 71 of the catheter 70 for removal of the device 130 from the air passageway 42 .
[0067] FIGS. 15-17 show a still further removable air passageway obstruction device 160 embodying the present invention. As shown in the initial collapsed state in FIG. 15 , the device 160 includes a plurality of frame supports 162 , 164 , 166 , and 168 . The frame supports extend between a proximal ring 170 and a distal ring 172 . The device 160 is preferably laser cut from a sheet of Nitinol.
[0068] Since each of the frame supports are identical, only frame support 164 will be described herein. As will be noted, the support 164 includes a bend point 174 with a relatively long section 176 extending distally from the bend point 174 and a relatively short section 178 extending proximally from the bend point 174 . The short section 178 includes a fixation projection or anchor 180 extending slightly distally from the bend point 174 .
[0069] FIGS. 16 and 17 show the device 160 in its deployed configuration. When the device is deployed, it is advanced down a catheter to its deployment site in its collapsed state as shown in FIG. 15 . When the deployment site is reached, the device 160 is held outside of the catheter and the rings 170 and 172 are pulled toward each other. This causes the device to bend at the bend points of the frame supports. This forms fixation projections 180 , 182 , and 184 extending into the inner wall of the air passageway to fix the device in position.
[0070] The relatively long sections of the frame supports are covered with a flexible membrane 186 as shown in FIGS. 16 and 17 to form a one-way valve. The valve functions as previously described to obstruct inhaled air flow but to permit exhaled air flow.
[0071] FIGS. 18-20 illustrate a manner of removing the device 160 from an air passageway. Once again a catheter 70 is advanced down a bronchoscope 118 to the device 160 . Next, a retractor including a forceps 120 and pin 190 are advanced to the device. The pin 190 , carrying a larger diameter disk 192 , extends into the device as the forceps 120 grasps the proximal ring 170 of the device 160 . The pin 190 continues to advance until the disk 192 engages the distal ring 172 of the device 160 as shown in FIG. 19 . Then, while the forceps 120 holds the proximal ring 170 , the pin 190 and disk 192 are advanced distally carrying the distal ring 172 distally. This causes the device 160 to straighten and collapse as shown in FIG. 20 . Now, the forceps 120 , pin 190 , and the device 160 may be pulled into the internal lumen 71 of the catheter 70 for removal of the device. As will be appreciated by those skilled in the art, the foregoing steps may be reversed for deploying the device 160 .
[0072] While particular embodiments of the present invention have been shown and described, modifications may be made, and it is therefore intended in the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the invention. | An air passageway obstruction device includes a frame structure and a flexible membrane overlying the frame structure. The frame structure is collapsible upon advancement of the device into the air passageway, expandable into a rigid structure upon deploying in the air passageway and recollapsible upon removal from the air passageway. The flexible membrane obstructs inhaled air flow into a lung portion communicating with the air passageway. The device may be removed after deployment in an air passageway by recollapsing the device and pulling the device proximally through a catheter. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a steam buffer operating in a steam engine power plant having a closed steam system and is designed to alternately accumulate and emit steam under high pressure and temperature.
2. Description of the Related Art
In a steam engine power plant there is a significant need for a buffer, because at any particular time the amount of steam normally generated and the amount of steam required by the plant do not always correspond to one another. Such storage in a buffer has typically been carried out in a steam accumulator. The steam accumulator consists of a pressure vessel, which is partly filled with water that is heated by a boiler or a steam generator capable of operating at a varying pace. When steam is supplied to the steam engine from the steam accumulator, the pressure tends to decrease. This pressure drop will subsequently cause a spontaneous generation of new steam from the heated water. By using this steam accumulator, large power outputs can be obtained, and the power outputs can be obtained independent of an irregular burning in the steam generator. However, this type of steam-accumulator has several drawbacks because it is heavy and bulky and because the large amount of water and steam at high temperature constitutes a great hazard in the event of fractures in the pressure vessel casing.
In a steam accumulator energy is stored in the pressurized water. There is also the consideration of storing the heat energy in other materials. Thus, it has long been desirable to use an energy storing material which can change between a solid and liquid phase for latent heat. However, when utilizing latent heat there can be problems at phase changes, such as contraction, tensions and chemical exhaustion, which gives rise to mechanical, chemical, heat transfer and functional problems.
SUMMARY OF THE INVENTION
A steam buffer shall accomplish a levelling between power input in the shape of the steam arriving from the steam generator and the power output to the steam engine. This will make it possible to use intermittent and variable energy sources like solar energy in stationary plants and above all will make it possible to obtain considerably higher peak power outputs for short periods than the power which the steam generator is capable of alone. This will also involve the possibility of permitting the burner in the steam generator to operate at a low and constant power even when the steam engine power output is strongly fluctuating.
In a steam engine for vehicular applications with large power output variations, an effective steam buffer makes it possible to design the steam generator at a level for the highest continuous power output required, which is considerably lower than the highest momentary power output that is necessary for only short periods, as for example at acceleration. Further, the steam buffer can also constitute a source of energy storage, which makes it possible to drive the vehicle a certain distance without any exhaust gases, that is no firing of a combustion engine.
An object of the present invention is to provide a steam buffer which is small and light and provides a high power density and energy density, so far not attained. In addition, the buffer provides such a design that it will provide increased safety from accidents when it is used together with steam engines in vehicle applications.
This is obtained by the present invention in that the steam buffer is equipped with a high temperature connection for steam and a low temperature connection for feed water. A large number of elongated flow channels with a hydraulic diameter smaller than about 0.5 mm for the steam and the feed water are between the two connections. These channels are surrounded by pressure resistance walls of a material having a melting point above the highest incident temperature in the buffer and constitutes the primary heat storage substance for the buffer.
In this way, the invention utilizes sensible heat, or temperature changes in solid material. The solid material that constitutes the pressure resistant walls of the flow channels is mainly responsible for the heat storage capacity of the steam buffer.
The invention is particularly distinguished in that the steam buffer consists of a large number, preferably the maximum possible number, of flow channels with a hydraulic diameter at least as small as 0.5 mm. Such small channels require a high pressure to feed steam and water therethrough. A pressure of at least 100 bar is required, which is a pressure that is appropriate for an efficient operating steam engine such as of the displacement type. Despite the high pressure, the expansion strain in the wall material surrounding the flow channels is limited. Since each flow channel itself has pressure resistant walls, there is no need for a pressure resistant vessel capable of being exposed to the high pressure for the whole steam buffer diameter. Thus, there is no danger of an explosion of the vessel and, as is shown below, no danger of outflowing steam exists in the case of damage to the steam buffer.
According to a preferred embodiment of the present invention, the steam buffer is designed, as well as the steam engine, for a pressure above the critical pressure, preferably 250 bar, and a corresponding steam temperature, preferably 500° C., using a hydraulic diameter of 0.2 mm. With these values, it is possible to obtain an energy density of 500 kJ/kg and a power density of 100 kW/kg for the steam buffer, which can be compared with, for example, a lead battery with only 100 kJ/kg and 100 W/kg.
According to a further preferred embodiment of the present invention, the flow channels are formed by using small grains, preferably of a ceramic material, sintered to each other and to the inside of the casing of the steam buffer. The flow channels are thereby formed, between the grains and between the grains and the casing sintered to the grains. The casing can be thin-walled because it is exposed to low expansion strain and mainly has a sealing function, but it also provides a heat storage function like the other material.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described in the following in more detail with reference to the attached drawings, which schematically show different preferred embodiments of the steam buffer according to the present invention.
FIG. 1 shows the layout of a steam engine power plant with a steam buffer.
FIGS. 2-5 are partial sections of the steam buffer according to the present invention illustrating preferred forms for the flow channels.
FIG. 6a is a schematic side view of the steam buffer.
FIGS. 6b-f show temperature profiles of the material in the steam buffer at different conditions of charging.
FIGS. 7a-d illustrate temperature profiles for both the channel material and the steam at the end of the discharge process from the steam buffer at different pressure values and different diameters for the flow channels.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 schematically shows a steam generator 1, which is connected by a steam pipe 2 to a high temperature connection 3 of the steam buffer 4 and to the inlet valve 5 of a multicylinder axial type piston steam engine 6. From the outlet port of the steam engine 6, a pipe 7 leads to a condenser buffer 8, to which a cooler 9 is connected by the pipes 10, 11 for cooling of the feed water and the steam in the condenser buffer 8. From the condenser buffer, a pipe 12 leads to a pump 13 for pumping feed water of high pressure to a low temperature connection 14 consisting of a long heat insulated pipe to the steam buffer 4 via a pipe 15. Pump 13 also feeds a pipe 16 to a circulation pump 17 having an outlet to a pipe 18 that is connected to the steam generator 1.
Between the high temperature connection 3 of the steam buffer 4 and the low temperature connection 14 extends a large number of flow channels 20 such as illustrated in FIGS. 2-5. These channels can be formed by a packet of capillary tubes 21 having ends that are extended into the connections 3 and 14 and outer surfaces sealingly adhering to each other and to the connections 3 and 14. The pipes 21 have circular cross sectional areas in FIG. 2, but can alternatively have hexagonal shapes like the pipes 22 in FIG. 3. The flow channels 20 can alternatively be formed by an extrusion of a block 23 of some suitable material in which the flow channels are extended. The pipes 21, 22 and the block 23 can be a metal or ceramic material. An especially preferred design is illustrated in FIG. 5. Within a thin-walled cylindrical casing 24 between the connections 3, 14 are a large number of small grains of ceramic material sintered to each other and to the inside of the casing 24. The flow channels 20 are here formed by the space between the grains 25 and between grains and the inner wall of the casing 24. In all of these embodiments for the buffer flow channels the hydraulic diameter of the flow channels 20 should be at least less than 0.5 mm.
The steam engine power plant generally operates as follows. The steam generator 1 is designed to generate steam in specified discrete power outputs, with a high and a low continuous power output level and preferably some intermediate levels that are chosen depending on the required steam generation. When the valve 5 is closed, the engine 6 is not getting any steam and all generated steam from the steam generator 1 will flow with the pressure of 250 bar and temperature of 500° C. to the steam buffer 4. In the steam buffer, the steam will penetrate the flow channels 20 and force the water inside the flow channels 20 out by the pipe 15 to a buffer vessel 26. Vessel 26 is connected to the pipe 15 and contains a gas cushion against the pressure of which the water is forced into the vessel. The channel material 21, 22, 23, 24 or 25 in the steam buffer 4 is heated from the connection 3 with a transverse temperature front, which moves towards the connection 14. When this temperature front has reached connection 14, the steam buffer is fully charged, and the circulation pump 17 is stopped. The power plant can remain in this fully charged condition for a long time period and is equipped with an effective heat-insulation 27. The insulation 27 houses the steam generator 1, the steam buffer 4 with connection 14, the valve 5 and the top of the steam engine 6 as well as the depending pipes, which together constitute a high temperature part. The rest of the plant constitutes a low temperature part with a temperature of approximately 80° C. Some heat losses will of course be unavoidable, but can be made so small that the losses can be compensated by starting the steam generator 1 and allowing it to run for only a couple of minutes after a several day interval period to restore the intended temperature level.
When the valve 5 is opened for driving the steam engine 6 at normal low load, the continuously generated steam from the steam generator will be enough. When the valve 5 is opened for driving of the steam engine 6 at high load for short time periods, for example during acceleration when passing another vehicle, the main steam will be supplied from the steam buffer 4. The steam buffer will preferably give in the order of ten times more steam than the steam generator 1 alone can supply. The steam leaves by connection 3, and the feed water from the buffer 26 is forced by the gas cushion into the steam buffer 4 through the connection 14. In the steam buffer 4, the water is vaporized by the surrounding hot material, and the temperature front moves slowly in the direction toward the connection 3. When this temperature front reaches the connection 3, the steam buffer is fully unloaded and only the steam from the steam generator 1 is available for use by steam engine 6.
The above described process of charging the buffer 4 is illustrated in FIGS. 6a-6f. FIG. 6a shows the steam buffer 4 with the low temperature connection 14 and the high temperature connection 3. At fully charged condition the temperature in the steam buffer from one end to the other end is as the curve illustrates in FIG. 6b, that is approximately 80° C. outside the heat insulation and 500° C. along the whole steam buffer length. After a long time in the fully charged condition, the temperature distribution along the long pipe in connection 14 is as FIG. 6b illustrates. The temperature gradient in connection 14 is responsible for the largest amount of heat leakage from the steam buffer 4, but this leakage can be made small if the pipe 14 is made long. During the discharge, the steam flows out via connection 3, and the water flows in via connection 14. The transverse temperature front T is then formed as according to FIG. 6c. The temperature front will move slowly towards the connection 3 with a velocity of propagation that is always lower than the velocity of the fluid of steam and water. The speed is related to the velocity of the flowing fluid and the heat capacity of the fluid and the heat exchanger material. The discharge will take place with an unchanged temperature and almost unchanged pressure of the discharged steam until the front T reaches the connection 3, as shown in FIG. 6d.
If the heat transfer conditions are favorable and the flow velocity is not too high, which is a function of the number of flow channels, there will be a very steep rise at the temperature front, which is important in order to obtain high energy density. The high energy density is defined as the real power output possible to be obtained compared to the material weight of the steam buffer. The real energy discharged is in turn the energy discharge that can be made with a guaranteed quality of steam from a fully charged steam buffer until the required steam quality is no longer available at the outlet 3. This latter condition is illustrated in FIG. 6d. During the whole discharge time up until the condition in FIG. 6d, the discharged steam has the same quality as the steam that charged the steam buffer. When the position in FIG. 6d is reached, feed water that has been flowing in at 14 has been heated to a nominal steam temperature by the heat transferred from all the material which transfers its energy content from 500° C. to 80° C. This occurs for all of the material through which the temperature front has passed, and the energy will correspond to the marked section Y in FIG. 6e. The ratio between Y and the entire section in FIG. 6b is defined as the ratio of utilization, which for the steam buffer according to the present invention can be between 85-95%. With high steam temperatures of 800°-900° C. that can be used if the whole steam system is designed in ceramics, it is possible to obtain an energy density of about 1 MJ/kg.
At repeated charging, the temperature front moves in the opposite direction, as is shown in FIG. 6f, until a new discharge takes place or the steam buffer becomes again fully charged, as in FIG. 6b.
A condition for obtaining a high energy density is a rise of the temperature front in the steam buffer that is as steep as possible, and it can be shown that a hydraulic diameter of the channels should be some tenths of a millimeter. It can also be shown that a high power density, defined as the power per kg which can be withdrawn without large unacceptable pressure losses, requires a high steam pressure, a high value on the ratio between the total area of the cross section of the flow channels and the total cross sectional area of the wall buffer material and the flow channels, a high steam temperature, a low density of the buffer material, which makes ceramic material favorable, and a small hydraulic diameter as with for a high energy density.
The hydraulic diameter and its influence on the steepness of the temperature front is illustrated in FIGS. 7a-7d at different operational modes. FIGS. 7a and b show the temperature of the steam buffer along its relative length at pressure 250 bar and steam temperature 500° C. for flow channels with a hydraulic diameter of 0.5 and 0.2 mm, respectively. Tg and Ta refer to the temperature curves for the wall material and the steam, respectively. FIGS. 7c and d show corresponding curves at a pressure of 100 bar and a steam temperature of 450° C. In both cases, it is illustrated that for a change from 0.5 to 0.2 mm for the hydraulic diameter the temperature steepness will increase dramatically, especially in the case with the higher pressure and temperature values.
Despite the high pressure and temperature of the steam engine power plant, there is a very low risk of damage to the surroundings from an explosion and/or outflowing of hot steam, especially from the steam buffer, because the steam buffer is not contained in a large pressure resistant vessel and because the flow channels will contain only a minor amount of hot steam/water. The steam will be generated at the same pace at discharge as the feed water flows into the flow channels and will only take place if the steam buffer is intact. It can also be equipped with a pipe break valve 30 in the pressurized pipe 15 which is leading the feed water to the steam buffer 4. A greater velocity of the feed water than a predetermined value, for example fully open valve 5 or full load, will rapidly close the valve 30, and the steam generation in the buffer 4 will stop.
The invention is of course not restricted to the above described steam buffer designs and steam data but can be modified in several ways within the scope of the present inventive idea defined by the claims. | Disclosed is a steam buffer for use in a steam engine power plant with a closed system and designed to alternately accumulate and emit steam under high pressure and temperature. The steam buffer improves upon conventional steam accumulators which contain water and steam at high pressures and temperature in a large pressurized vessel. The steam buffer functions to store heat in solid material in the walls of a large number of long flow channels with a hydraulic diameter at least as small as 0.5 mm contained in a casing. The flow channels may be formed, for example, by capillary tubes attached to each other or, alternatively, by fine grains of metallic or ceramic material sintered together. The walls of the flow channels perform as the primary heat storing material and are made of a material having a melting point higher than the operating temperature in the steam buffer. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates generally to yarns, fabrics and protective garments knitted of such yarns. More particularly, the present invention relates to a yarn core construction which provides improved comfort, flexibility and pliability in both protective garments such as a gloves and also a variety of other applications.
In many industries, it is desirable to provide protective garments, particularly gloves, to protect employees from being cut. Ideally, such garments should be flexible, pliable, soft and cut resistant. Typically, any improvement in the last of these characteristics has usually been at the sacrifice of the others. Protective garments have been made cut resistant in the past through the use of yarns which contain wire. However, the use of wire is problematic in environments where a protective garment must not be electrically or thermally conductive. Moreover, experience has shown that the wire may break and injure the hand of the wearer. Lastly, articles or garments having a high wire content may be difficult and/or expensive to clean using conventional cleaning techniques.
In response to these problems, non-metallic cut-resistant yarns have been developed. These yarns have been described in U.S. Pat. No. 5,177,948 to Kolmes et al. which is owned by the assignee of the present invention. The contents of that patent are incorporated herein by reference. Kolmes describes a yarn having substantially parallel core strands which may include fiberglass. Kolmes does not describe wrapping an untwisted fiberglass yarn with a sheath yarn so as to change the knitting characteristics of the fiberglass yarn. Subjecting a fiberglass yarn strand to severe twisting degrades its performance and impedes its knittability. It is believed that some of the individual filaments of a multi-filament fiberglass yarn strand are not picked up cleanly by the needles of a conventional knitting machine. Thus the strands, given their inherent brittleness, break easily during knitting. These problems have prevented use of the yarns described in Kolmes extensively outside of traditional cut/abrasion resistant applications because they have not had desirable characteristics for uses such as fashion apparel.
There remains a need for a cut-resistant yarn core construction having a fiberglass component, which, when incorporated with other yarns into a composite yarn, is suitable for knitting into a fabric, protective garment or other article having improved flexibility and softness.
SUMMARY OF THE INVENTION
The present invention relates to a composite core yarn construction formed of a substantially untwisted fiberglass strand wrapped with another yarn. This construction renders the normally difficult to knit fiberglass much more supple and flexible thus improving its manufacturing qualities. The yarn offers increased strength in a finer denier. Articles manufactured from the yarn can be expected to be more comfortable without the drawbacks seen in previous cut/abrasion resistant articles.
The present invention includes a flexible, composite, cut and abrasion resistant yarn comprised of a substantially untwisted fiberglass strand having a denier of between about 100 and about 1200 and a sheath strand having a denier of between about 200 and about 700. The cover strand is wrapped around the fiberglass core strand at the rate of at least 8 turns per inch. The yarn could further comprise a non-metallic covering including a bottom cover strand wrapped about the yarn in a direction opposite to that of the sheath strand; and a top cover strand wrapped about said bottom cover strand in a direction opposite to that of the bottom cover strand.
The yarn desirably has a composite denier of from about 1800 to about 5000.
Another embodiment of the present invention could include two fiberglass strands in the core construction. Here the non-metallic composite core would include a first fiberglass strand and a second fiberglass strand, the second fiberglass strand being substantially parallel to and in an untwisted relationship with the first fiberglass strand. In this embodiment the first and second fiberglass strands have a combined denier of about between about 200 and about 600. This core construction of this embodiment further includes a sheath strand having a denier of between about 200 to about 600, the sheath strand being wrapped around the first and second fiberglass strands at the rate of at least 8 turns per inch. This embodiment also includes a non-metallic covering wrapped on the core. The covering includes a bottom cover strand wrapped about the core in a direction opposite to that of the sheath strand, the bottom cover having a denier of about 650 and being formed of fibers or filaments of extended chain polyethylene. The covering also includes a top cover strand wrapped about the bottom cover strand in a direction opposite to that of the bottom cover strand, the top cover strand having a denier of about 400 and being formed from fibers or filaments of nylon. This embodiment has a composite denier of between about 1800 and about 5000.
Therefore one aspect of the present invention is to provide a core yarn construction for a cut/abrasion resistant composite yarn featuring a knittable covered fiberglass strand.
Another aspect of the present invention is a core yarn construction which provides strength characteristics of prior art yarns in a finer denier.
BRIEF DESCRIPTION OF THE DRAWINGS
The various benefits and advantages of the present invention will be more apparent upon reading the following detailed description of the invention taken in conjunction with the drawings.
In the drawings, wherein like reference numbers identify a corresponding component:
FIG. 1 illustrates the core yarn construction in accordance with the principles of the present invention.
FIG. 2 illustrates the yarn depicted in FIG. 1 with the addition of two covering strands.
FIG. 3 is an illustration of an alternative embodiment having a two fiberglass strand core.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning to FIG. 1, the yarn core construction of the present invention is referred to generally at 10. The non-metallic core includes a single substantially untwisted fiberglass strand 16 and a sheath strand 18. The sheath strand is wrapped around the fiberglass strand at a rate of at least 8 turns per inch. As used herein the term cover does not require that the sheath strand completely cover or coat the single fiberglass strand. Rather the cover strand must have a sufficient number of turns per inch to give a substantially untwisted fiberglass core strand the properties discussed herein below.
At this point the core yarn may be knit for a variety of new uses as is described in more detail herein below. However, to improve its manufacturing qualities, the yarn may further include a non-metallic covering wrapped on the core yarn as shown in FIG. 2. There the core yarn construction described above includes a covering including a bottom cover strand 20 wrapped about the core in a first direction which may be opposite to that of the sheath strand. A top cover strand 22 may be provided wrapped about the bottom cover strand in a second direction opposite to that of the bottom cover to complete the yarn of the present invention. Each of the strands used in the present invention is non-metallic.
The fiberglass strand (or strands) in the core may be either E-glass or S-glass of either continuous filament or spun. The practice of the present invention contemplates using several different sizes of commonly available fiberglass strand, as illustrated in Table 1 below:
TABLE 1______________________________________ Fiberglass Approximate Size Denier______________________________________ G-450 99.21 D-225 198.0 G-150 297.6 G-75 595.27 G-50 892.90 G-37 1206.62______________________________________
The size designations in the Table are well known in the art to specify fiberglass strands.
These fiberglass strands may be used singly or in combination depending on the particular application for the finished article. By way of non-limiting example, if a total denier of about 200 is desired for the fiberglass component of the core, either a single D-225 or two substantially parallel G-450 strands may be used. The two G-450 strands preferably are in an untwisted relationship with each other. This embodiment is illustrated in FIG. 3 where the core construction is composed of a first fiberglass strand 30 and a second fiberglass strand 32 which is substantially parallel to and in an untwisted relationship with the first fiberglass strand. In a preferred embodiment these strands will have a combined denier of about between 200 and about 600. The yarn further includes a sheath strand 18 having a denier between about 200 and about 600. The sheath strand is wrapped about the fiberglass strands at a rate of at least 8 turns per inch and preferably about 12 to 14 turns per inch.
This dual fiberglass strand core embodiment may further include a non-metallic covering as described above. In a preferred embodiment the bottom cover may have a denier of about 650 and be formed of fibers or filaments of extended chain polyethylene.
The top cover strand may have a denier of about 400 and may be formed from fibers or filaments of nylon. In this embodiment the yarn has a composite denier of between about 1800 and about 5000.
It should be understood that the table above illustrates currently available fiberglass strand sizes. The practice of the present invention contemplates the use of other fiberglass strand sizes as they become available in the market or as found to be suitable for particular applications.
Suitable types of fiberglass fiber are manufactured by Corning and by PPG. The fibers have the desirable properties of relatively high tenacity, of about 12 to about 20 grams per denier, resistance to most acids and alkalis, being unaffected by bleaches and solvents, resistance to environmental conditions such as mildew and sunlight, and high resistance to abrasion and to aging.
The sheath strand may have a denier of from about 200 to about 400 and may be formed of fibers or filaments selected from the group consisting of high performance yarns such as extended chain polyethylene or aramid, or from more conventional yarns such as nylon and polyester. Desirably the sheath strand is formed from a textured yarn particularly when it is formed from nylon. In a preferred embodiment the sheath strand has a denier of about 375. Desirably, the single fiberglass strand has a denier of about 200.
The selection of the sheath strand will depend in part on the desired properties and end use of the finished yarn. For example, an extended chain polyethylene such as that sold under the SPECTRA® brand may be used for its durability and abrasion resistance. Other suitable materials include aramid such as Dupont's KELVAR® fiber, a polyethylene fiber such as CERTRAN® fiber manufactured by Hoechst Celanese. The CERTRAN® fiber is believed to provide performance similar to the SPECTRA® fiber at a lower cost. Another Hoechst product, VECTRAN® fiber, is suitable where high heat resistance is important for the finished article. This fiber is a polyester based liquid crystal fiber which is also desirable for use in cut-resistant articles. Again, the selection of a particular fiber will depend on cost considerations and the end use of the article constructed from the yarn.
The selection of the sheath strand may also depend on the denier of the first core strand. The finer the denier used in the first core strand the finer the sheath strand. The size of the sheath strand increases with the size of the first core strand.
The bottom cover 20 is wrapped about the core in a direction opposite to that of the sheath strand, and, in a preferred embodiment, is formed of extended chain polyethylene. The bottom cover may have a denier of about 500 to about 800 and desirably about 650. The bottom cover 20 is wrapped about the core at a rate of about 7 to 10 turns per inch, and preferably about 8 to 9 turns per inch. The number of turns per inch for the bottom core decreases as heavier strands are used in the core. Other suitable materials for the bottom cover include aramid, polyester, and nylon.
The top cover 22 is wrapped about the bottom cover in a direction opposite to that of the bottom cover and has a denier of from about 400 to about 800, and preferably of about 500. The top cover may be wrapped about the core and the bottom cover at a rate of about 8 to about 11 turns per inch, preferably at a rate of about 9 to about 10 turns per inch.
Desirably, top cover 22 is formed from nylon. Other suitable materials for the top cover include extended chain polyethylene, aramid, and polyester.
The use of a top cover will be determined by the need to provide better coverage for the core, to balance the overall yarn construction, or to make the yarn more knittable. The end use of a article constructed from the yarn may determine the need and material selection for the top cover. For instance, if the yarn will be knit into a fabric which will be dyed, polyester or nylon may be used for the top cover to take advantage of the relative ease with which they may be dyed.
In a preferred embodiment the overall denier of the yarn of the present invention to include the fiberglass strand, the sheath strand, the bottom cover, and the top cover is from about 1800 denier to about 5000 denier.
By way of non-limiting example, yarn constructions utilizing the principles of the present invention are illustrated as Examples 1 and 2 in Table 2 below:
TABLE 2______________________________________ Example 1 Example 2______________________________________Core Fiberglass G-75 G-150Sheath 650 Spectra ® Fiber 375 Spectra ® FiberBottom Cover 650 Spectra ® Fiber 650 Spectra ® FiberTop Cover 1000 polyester 500 polyester______________________________________
The Example 2 yarn would be knit using a 10 gauge knitting machine while the Example 1 yarn would be knit using a 7 gauge knitting machine.
The yarn of the present invention may be manufactured on standard knitting equipment. If the yarn will be provided with the cover layers, preferably the untwisted fiberglass strand is wrapped with the cover strand in a first step. Next, the bottom and top cover strands are added in a second operation on a separate machine.
The yarn of the present invention has several advantages over the non-metallic cut resistant yarns described herein above. Understanding these advantages requires a discussion of the properties of fiberglass strand material and its use in making yarns. Fiberglass has excellent tensile strength properties that make it attractive for use in a cut or abrasion resistant article. However, fiberglass is also quite brittle making it difficult to knit fiberglass fibers on conventional knitting equipment. Fiberglass strands cannot make the required sharp turns around knitting machine components without breaking. This breakage can cause the fiberglass component of a yarn to wash out presenting a fuzzy or "hairy" appearance.
The brittle nature of fiberglass also prevents it from being formed into a twisted composite yarn structure. The process of twisting the fiberglass with another yarn causes the fiberglass to make sharp turns and thus develop fracture points along the fiberglass strand leading to the problems described above. It should be understood that the fiberglass strands contemplated for use in the present invention typically are composed of a number of filaments held together by some amount of twist. However, the detrimental twisting discussed here refers to combining two or more parallel singles yarns into a multiple strand yarn.
It has been discovered that wrapping a cover strand around a fiberglass strand permits the fiberglass strand to make the sharp turns required in a knitted article without breaking. It is believed that the sheath yarn helps to hold the fiberglass filaments in place and to protect them from breakage. The resulting composite yarn is more supple and has more strength. That is, a thinner yarn may be constructed having the same strength as previous yarns using two parallel core strands, one fiberglass and one non-fiberglass. In those constructions the fiberglass strand acts as a supporting strand for the second strand which is relied upon for the cut/abrasion resistant quality. As will be understood by one of ordinary skill in the art, the core construction of the present invention offers the same performance in a yarn that has improved manufacturing characteristics. Moreover, the yarn may be manufactured at reduced cost for the same measure of performance.
In its broadest sense the present invention comprises a fiberglass supported core yarn having a substantially untwisted fiberglass strand and a sheath yarn strand wrapped about the fiberglass strand. The sheath strand is wrapped about the fiberglass strand at a rate of at least 8 turns per inch. The term core yarn means the combination of the fiberglass strand and the sheath strand which is intended to be used: 1) alone as the core construction of a composite yarn or 2) as one component of a multiple-component composite yarn core. In the first usage the core yarn of the present invention may be covered with another yarn or yarns. In the second usage, it is believed that the core yarn may be laid parallel to another yarn or yarns, or may be twisted or braided with another yarn or yarns to form a composite yarn core.
The untwisted fiberglass strand and the cover strand mutually benefit each other. The fiberglass component acts as a support for the cut/abrasion resistant cover and the cover permits the brittle fiberglass to be knit on conventional knitting machinery. Properties of the resulting yarn may be varied by the choice of yarn composition, denier and the rate of wrap (turns per inch) of the sheath yarn about the fiberglass strand.
It should be noted that the core construction of the present yarn may be put to use without the use of the cover yarns. However, given the benefits of manufacturing ease and final use options for the finished product, the cover yarns are desirable.
The yarn construction of the present invention permits the finished product to have more of the cut-resistant material in a given length compared to a yarn having a core with two parallel strands. For example, in 12 inches of such a prior art yarn structure, there will be 12 inches of both fiberglass and a cut resistant material such as SPECTRA® fiber in the yarn core. In a 12 inch length of the yarn of the present invention, the fiberglass supports from about a 30% to about 50% longer length of a cut resistant yarn with no penalty in increased bulk because the SPECTRA® fiber is wound around rather than laid alongside the fiberglass core.
Another advantage of the yarn of the present invention is the ability to control yarn properties through the selection of the sheath strand. It has been discovered that the use of the textured nylon creates a stronger yet soft, more breathable yarn. The use of a non-textured flat yarn creates a smoother core surface. It is believed that the sheath strand expands about the single fiberglass strand to create these properties.
The advantages discussed above expand the known range of suitable uses for cut/abrasion resistant fabrics. Possible new uses include fire hoses, motorcycle jackets, seat covers for automobiles, airplanes and buses, protective clothing/padding for skaters, the toe/heel regions of hosiery and outerwear fabrics. The last of these uses is significant as known cut or abrasion resistant fabrics have been used primarily for industrial applications, e.g. meat packing facilities, and not for everyday clothing. Previously these fabrics did not have the suppleness, hand or appearance characteristics suitable for fashion apparel.
Although the present invention has been described with preferred embodiments, it is to be understood that modifications and variations may be utilized without departing from the spirit and scope of this invention, as those skilled in the art would readily understand. Such modifications and variations are considered to be within the purview and scope of the appended claims and their equivalents. | The present invention relates to a yarn core construction suitable for forming a flexible composite yarn having a fiberglass component. The resulting yarn has good cut and abrasion resistance qualities without sacrificing knittability, flexibility and suppleness. A normally hard to knit fiberglass strand is wrapped with a sheath strand at a rate of at least 8 turns per inch. The core thus formed provides all of the benefits of a fiberglass supported yarn without experiencing any of the manufacturing difficulties normally associated with fiberglass yarns. The core may also be provided with a multi-layer covering to balance the yarn and to further improve knittability. | 3 |
BACKGROUND OF THE INVENTION
This invention relates to a straw spreader for spreading straw discharged from a combine harvester.
For zero till and low till farming practices, it is fundamentally more important to ensure that straw discharged from the rear discharge opening of a combine is spread effectively over the ground. This spreading action prevents the collection of trash at specific locations on the ground which would interfere with seeding in the subsequent harvesting year. In addition the effective spreading of the straw across the ground can assist in retaining moisture over most of the ground rather than in specific areas where the straw lands if not properly spread. Furthermore the nutrients from the straw are applied equally across the ground.
Conventionally the combine harvester includes a chopper at a rear discharge opening of the combine so the straw emerging from the rear of the straw walkers is vigorously chopped into short lengths and discharged rearwardly and downwardly from the rear opening of the combine. This action merely dumps the straw onto the ground in a stream behind the combine with little or no spreading action to the sides. Other devices have been proposed for addition onto the combine to provide a chopping and spreading action. One problem which arises with devices of this type is that they are mounted relatively high on the combine and this causes the spreading action to be adversely affected by wind movement. This wind effect on the straw can alter the desired even spread so the material is spread in bands across the ground. Furthermore, the relatively high discharge causes the wide spread of large amounts of dust which can interfere with the driver's operation of the combine.
SUMMARY OF THE INVENTION
It is one object of the present invention, therefore, to provide an improved straw spreader for attachment to a combine which allows a more effective and even spreading action.
It is a further object of the present invention to provide a spreader for attachment to a combine which reduces the amount of dust discharged around the combine.
As yet further object of the present invention to provide a straw spreader which can be readily attached and removed from the combine.
As a yet further object of the present invention to provide a straw spreader which can be used to vary the amount of straw spread on the ground relative to the amount of straw taken from that portion of the ground.
According to a first aspect of the invention there is provided a straw spreader for a combine harvester comprising a frame, at least one ground wheel on the frame for engaging the ground and supporting the frame at a predetermined height relative to the ground, hitch means for coupling the frame to a rear part of the combine for transportation behind the combine, spreader means mounted on the frame for discharging straw in a spread pattern outwardly to at least one side of the frame and guide means for receiving straw from a discharge opening of the combine and transporting the straw to the spreader means.
According to a second aspect of the invention there is provided a straw spreader for a combine harvester comprising a frame, at least one ground wheel on the frame for engaging the ground and supporting the frame at a predetermined height relative to the ground, hitch means for coupling the frame to a rear part of the combine for transportation behind the combine, spreader means mounted on the frame for discharging straw in a spread pattern outwardly to at least one side of the frame guide means for receiving straw from a discharge opening of the combine and transporting the straw to the spreader means, storage means for storing and accumulating chopped straw from the discharge opening of the combine and means for transporting the straw from the storage means to the spreader means such that the amount of straw spread on a portion of the ground can be varied relative to the amount of straw collected from that portion of ground.
The low position of the spreader relative to the ground reduces the effect of the wind on the spreading action which means:
(a) the dust is maintained closer to the ground and is less problem;
(b) the spread pattern is less affected by wind action and is more consistent.
With the foregoing in view, and other advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, the invention is herein described by reference to the accompanying drawings forming a part hereof, which includes a description of the best mode known to the application and of the preferred typical embodiment of the principles of the present invention, in which:
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a rear portion of a combine harvester to which is attached a straw spreader according to the present invention.
FIG. 2 is a rear elevation of the straw spreader and combine of FIG. 1.
FIG. 3 is a side elevation of the straw spreader and rear of the combine of FIG. 1.
FIG. 4 is a schematic side elevational view of an alternative straw spreader including an accumulator.
In the drawings like characters of reference indicate corresponding parts in the different figures.
DETAILED DESCRIPTION
The rear portion of a conventional combine is indicated generally at 10 mounted on the ground wheels 11 for transportation of the combine across the ground in a crop harvesting action. The details of the combine will not be described herein as they are conventional and vary from machine to machine but generally the machine includes a rear housing 12 which covers the straw walkers 13 together with a chaffer sieve 14. The machines shown is of the self-propelled type but also the invention can be used with a pull-type in which the wheels are moved forwardly. From the rear end of the straw walker the separated straw discharges onto a chopper 15 which rotates around a horizontal axis and extends across the width of the rear part of the housing so that all of the straw falling from the straw walker is chopped into short lengths and discharged outwardly through a discharge opening 16 across the lower edge of the rear face of the combine housing 12. The separated chaff from the sieve 14 is discharged from an area beneath the housing 12 through an opening indicated at 17 at a position generally between the rear wheels 11 of the combine.
Without the addition of any spreader arrangement, the straw would be deposited on the ground generally rearwardly of the combine over a width not significantly greater than that of the rear end of the combine and the chaff also would merely fall onto the ground over the same area.
The present invention therefore provides a straw spreader arrangement which may also incorporate a chaff spreader arrangement for receiving the straw discharged rearwardly from the combine and for spreading the straw over a greater width than the combine to obtain, as far as possible, an even spread across the ground.
The spreader comprises a metal frame 20 in the form of a rectangular structure defined by plurality of coupled beams. Specifically the frame includes a pair of side arms 21 and 22 which form two top side rails of the frame and continue forwardly from the frame to form a hitch section 23 defined by the forward portions of the arms indicated at 21A and 22A respectively.
In addition the frame includes vertical rear struts 24 and 25 and horizontal rear frame elements 26 and 27 at a top and bottom respectively of the frame. Forward cross frame elements 28 are provided at the front of the frame at the top and bottom respectively with the top frame element only being visible in the drawings. The frame further includes horizontal side frame elements at the bottom of the frame parallel to the arms 21 and 22 but again these are not visible in the drawings. The frame may be braced by various diagonal bracing elements to form a box structure.
A pair of castor wheels 30 and 31 are provided for supporting the frame and these are mounted for castoring action on the cross frame element 27 at the bottom of the frame.
The rear part of the combine 10 includes a vertical frame element 35 which is rigidly attached to the combine and forms a structural member thereof. This vertical frame element is positioned adjacent the ground wheels approximately five or six feet forwardly from the discharge opening 16 and the arms 21A and 22A extend from the frame forwardly for connection by inwardly extending coupling elements 35A to the vertical frame element 35. A pivot pin 36 allows the arms to move upwardly and downwardly as the height of the frame varies relative to the rear end of the combine as the device moves over rougher terrain while preventing the device from twisting or moving side to side relative to the combine. The height of the frame is governed by the ground wheels 30 and 31 so that the height of the device is substantially independent of the height of the rear part of the combine which can thus twist as the combine goes over the ridge or through a valley.
The frame carries a pair of spreader elements 40 and 41 which together provide a spreading action on the straw discharging from the rear of the combine. Each of the spreader elements is mounted upon a frame structure 42 extending outwardly from one side of the frame. The frame structure 42 supports a horizontal circular plate 45 which is fixed relative to the frame structure and thus is held against rotation. Around one part of the periphery of the circular plate 45 is mounted an upstanding guide wall 46. As shown in FIG. 1 the guide wall 46 extends from approximately the 11:00 position to approximately the 5:00 position of the left hand spreader assembly so that straw is prevented from escaping from the top of the plate 45 around the area where the guide wall is provided but is free to escape outwardly to the sides and rearwardly over the area where the guidewall is omitted over a spread pattern shown in dotted line which includes the sides and the rear of the device.
A smaller plate 47 is mounted on top of the plate 45 and is rotatable relative thereto mounted upon a shaft (not shown) carried in bearings 43 and driven for rotation about a vertical axis by a hydraulic motor 44. The smaller circular plate 47 carries the pairs of fins 48 and 49 which extend diametrically of the plate 45 and standing upwardly therefrom in so that the fins cross at the axis of rotation of the plate 47. The fins thus comprise substantially a simple vertical wall but a centre portion of the vertical wall is reduced in height as indicated at 50. The reduced height position acts to draw the material into the center of the spinner. The blades can be canted forwardly out of the vertical plane to prevent material escaping upwardly from the blades so that the material leaves the blades generally at right angles to the blade over the spread pattern shown.
In addition the frame carries a guide system for directing the straw discharging from the opening 16 onto the spreader assemblies. The guide system is shown on the right hand side of FIG. 1 and includes an apex portion 60 which includes a vertical line centrally of the discharge opening 16 and arranged to divide the straw driven outwardly from the opening 16 into two halves. The apex portion discharges and has diverging walls 61 extending rearwardly and outwardly with a forwardly facing portion for receiving the rearwardly discharged straw to turn it outwardly toward the spreader assembly. The curved guide wall 61 carries a top plate or upper surface 62 which faces downwardly and controls the flow of the straw and the air stream from the chopper of the combine so that it moves outwardly and then downwardly onto the top of the spreader assembly particularly at the central area defined by the portion of reduced height of the fins. The curved wall 61 is open at the bottom across the full area of the bottom with the momentum of the straw and the flow of the air stream causing the straw to pass from the apex 60 around the wall 61 to drop onto the spreader. The control of the straw into the spreader is caused by the slowing action of the increased curvature of the wall 61 and by the downward air stream generated into the centre of the spreader. The spreader then directs the air outwardly in a horizontal direction over the area which is free from the guide wall 46. A plate 64 is mounted at the discharge opening 16 of the combine and extends outwardly therefrom in the substantially horizontal plane across the full width of the opening 16. This plate acts to direct the material into the guide portion on the frame so that it is injected into the guide portion at a sufficient height to swirl around and to drop onto the spreader plates. The apex portion 60 is mounted on the plate 64 and is fixed thereto. The walls 61 can move relative to the apex portion as the rear of the combine lifts and lowers relative to the spreader device.
The straw spreader described above has the advantages that the spreader plates are mounted as close to the ground as possible that is at a height of approximately nine to fifteen inches from the ground and this position has two effects. Firstly, it reduces the amount of dust which is directed upwardly from the spreader action to avoid the combine becoming enveloped in the grain dust which is detrimental and can cause difficulty in operation. Secondly, the spreading actions takes place at a height which is much closer to the ground than conventionally and this is beneath the majority of the effect of the wind blowing across the ground so that the spreading action is much less dependent upon any cross winds which could otherwise interfere with the spread pattern.
The mounting of the spreader as a separate assembly on the rear of the combine carried by its own ground wheels and pivotal relative to the combine ensures that the spreader cannot be grounded by the combine passing over rough terrain. In addition the spreader is maintained at a proper height for the spreading action and the spreading action is thus much more consistent obtaining a more consistent spreading effect.
The system uses energy from the conventional chopper of the combine and the air flow from that chopper to move the material to the spreader. The shielding is designed to control ths air flow to obtain the required movement. The system provides a delay or dwell in the discharge of the straw sufficient to move the material from the position at which it is cut so that some averaging between heavy and light crop areas can be obtained.
A chaff spreader 70 is mounted under the chaffer sieve 14 so as to receive the chaff exiting therefrom and to spread it outwardly to the sides in a spreading action generated by rotating fins substantially of the type previously described. Two nozzles 71 and 72 are formed by the configuration of a surrounding wall 73 so the material is caused to spread outwardly preferentially to the sides of the combine. The chaffer 70 is mounted upon a cross beam 75 carried upon a pair of vertical straps 76 attached to the arms 21A and 22A respectively.
The chaff spreader and the straw spreader are therefore provided as a single unit which can be readily attached and detached from the rear of the combine as required.
The device of movement of the spinners of the chaff spreader and straw spreader are cumulative to improve the air flow outwardly from the sides of the combine. The chaff spreader is shielded on all sides by the combine itself and by the device.
Turning now to FIG. 4 the rear of a combine is again indicated at 10 and includes a straw discharge area 80 and a chaff discharge area 81 as previously described. In this case the spreader includes an accumulator in the form of a trailer vehicle 83 mounted upon rear wheels 84 and front wheels 85 and drawn by a hitch 86. The front wheels are steerable by the hitch in a wagon steering action so the trailer properly follows the combine.
A transfer assembly 87 is provided which includes a housing 88 defined by side walls and a base wall with the base wall being inclined upwardly and rearwardly. Just above the base wall is provided a conveyor assembly 89 including suitable drive mechanism and either an endless belt or chains and cross slats as required.
A guide chute 90 directs the material from the chopper at the discharge 80 onto the conveyor 89 so as to carry the material upwardly into the trailer 83.
The guide duct 88 is carried on a frame 91 which includes two arms 92 which project forwardly therefrom for coupling to the combine in the same manner as the arms 21A and 22A previously described. In this case the rear part of the frame is carried upon a single castor wheel 93 which supports a forward end of the hitch 86. The chaff spreader assembly 94 is substantially the same as previously described and is carried upon straps 95 as previously described.
Inside the trailer is provided a conveyor arrangement 96 which transports the straw material rearwardly to a spreader 97 of the construction previously described including the guide surfaces and spreader assemblies as described previously and positioned at relatively low height to obtain the previously described spreading action.
The accumulator provided by the trailer 83 enables the operator to vary the amount of straw spread relative to the amount of straw collected at a specific point on the ground.
Many farms have land which is variable in crop producing ability due to various factors. In the conventional approach where the straw taken from the ground is applied directly back to the ground by the spreading action, those areas which produce more lush crop receive back onto the soil more nutrients from the decomposing straw thus tending to maintain the difference between the crop producing areas. It is proposed therefore that the accumulator should be used to reduce the amount of straw spread over the ground at the areas of improved crop production and to maintain that straw in the accumulator for spreading over the areas of lower crop production for purposes of increased moisture retention and increased nutrient return.
Since various modifications can be made in my invention as hereinabove described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without departing from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense. | A straw spreader for the rear straw discharge of a combine comprises a frame mounted on ground wheels together with a pair of hitch arms which extend forwardly from the frame on either side of the rear portion of the combine for attachment to the combine frame structure. The separate frame can thus move up and down relative to the rear of the combine and maintains a pair of spreader spinners on the frame at a predetermined height relative to the ground. Guide surfaces collect the material from the chopper at the rear of the combine and direct it onto the spinners for a spreading action. The low height of the spreading action reduces dust emission and enhances spreading consistency. An accumulator can be provided between the spreader and the discharge in the rear of the combine to allow the amount of straw spread to be varied relative to the amount collected at any particular point on the field. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a linear piston pump, and more particularly to a permanent magnet linear piston pump.
[0003] 2. Description of the Related Art
[0004] The advantages of the magnetic-force linear piston pump contain a high operating pressure, a simple structure, a low consumption of energy and noises and a long durability. Therefore, it becomes more and more important and is applied to more and more applications. The mechanical movement and principle of the magnetic-force linear piston pump are similar to those of the plunger pump. Both of them take advantage of the relative reciprocating motion between the piston and the cylinder body to incur the variable capacity of the sealed piston cavity inside the pump, thereby inputting and outputting the fluid medium. A prior disclosure of CN1554868 as published on 2004 Dec. 15 and named by “magnetic-force linear piston pump” discloses a magnetic-force linear piston pump which comprises a housing in which a cylinder body and a piston are disposed. The piston is disposed inside the cylinder body with an axial movable airtight fit. On the outer periphery of the cylinder body is an electromagnetic coil. The electromagnetic coil is fixed into the housing. The electromagnetic coil is connected to an oscillating power supply. A permanent magnet is further disposed on the outer periphery of the cylinder body. The permanent magnet and the cylinder body are connected and positioned. One end of the piston is fixed to the housing, and the other end thereof is disposed within an inner hole of the cylinder body. A fluid hole is disposed on the piston. A first unidirectional valve and a second unidirectional valve are relatively disposed in the fluid hole or in the inner cavity of the cylinder body, thereby constructing three opposite and independent cavities in sequence, namely a low-pressure cavity, a variable-capacity operating cavity and a high-pressure cavity. The low-pressure cavity is communicated with an inlet pipe. The high-pressure cavity is communicated with an outlet pipe. However, since the electromagnetic coil is disposed inside the housing, the structure is unreasonable, which incurs an inconvenient installation. Furthermore, the electromagnetic coil and the permanent magnet are all set in the low-pressure cavity, so the sealing treatment to the electromagnetic coil and the permanent magnet is necessary, which incurs a complexity of the manufacture, high costs and hard promotions.
SUMMARY OF THE INVENTION
[0005] The object of the present invention is to overcome the aforementioned problems and to provide a permanent magnet linear piston pump having a simple structure, more convenient manufacture and lower costs.
[0006] The permanent magnet linear piston pump in accordance with the present invention comprises a piston body, a cylinder body, a permanent magnet assembly and an electromagnetic coil. It is characterized in that the cylinder body is in a shape of a polygonal prism, an interior of which arranges a piston cavity formed by an axial columnar accommodating cavity. The piston body is arranged in the piston cavity by a liquid sealing movable fit mode. A one-way inlet valve and a one-way outlet valve are disposed on an end face of the piston cavity opposite to an end face of a piston. A set of permanent magnet assembly is disposed on at least one side surface of the cylinder body. The permanent magnet assembly includes an inner mounting plate and an outer mounting plate disposed parallel to the side surface of the cylinder body. The inner plate and the outer mounting plate are made of a permeability magnetic material. An inner magnetic body and an outer magnetic body are respectively disposed on opposite surfaces of the inner mounting plate and the outer mounting plate. The inner magnetic body and the outer magnetic body are disposed oppositely and provide contrary magnetic poles at opposite faces thereof. A coil supporting member is disposed at an outside surface of the cylinder body. The electromagnetic coil is axially and distributively wound around the coil supporting member into a barrel shape. A barrel wall formed by the electromagnetic coil is disposed between the inner magnetic body and the outer magnetic body. An axial sliding slot is formed on the side surface of the cylinder body where the permanent magnet assembly is disposed. A connecting post is disposed on a side surface of the piston body in a radial direction to fit in with the sliding slot by a clearance fit mode. The connecting post penetrates through the sliding slot to be in connection with and in linkage with the inner mounting plate and the outer mounting plate.
[0007] By comparison with the prior technique, the present invention has the electromagnetic coil which is axially and distributively wound around the coil supporting member at the outside surface of the cylinder body and needs not subject the electromagnetic coil to a sealing treatment, which attains a simple structure, more convenient manufacture, lower costs, a reliable operation and convenient maintenance.
[0008] Preferably, two parts of the columnar accommodating cavity in the cylinder body are disposed symmetrically. The piston body is disposed at a middle portion of the columnar accommodating cavity. Two ends of the piston body are in cooperation with the two parts of the columnar accommodating cavity by the liquid sealing movable fit mode respectively, whereby the two parts of the columnar accommodating cavity are respectively defined as a first piston cavity and a second piston cavity, and the two ends of the piston body are respectively defined as a first piston body and a second piston body. A first one-way inlet valve and a first one-way outlet valve are disposed on an end face of the first piston cavity opposite to an end face of the first piston body. A second one-way inlet valve and a second one-way outlet valve are disposed on an end face of the second piston cavity opposite to an end face of the second piston body. A first inner magnetic body and a second inner magnetic body are respectively and symmetrically disposed at two ends of the inner mounting plate. A first outer magnetic body and a second outer magnetic body are respectively and symmetrically disposed at two ends of the outer mounting plate. A first electromagnetic coil and a second electromagnetic coil are respectively and correspondingly disposed on ribs at two sides of the cylinder body. Accordingly, the same cylinder body forms two permanent magnet linear piston pumps, and the piston body can be in the operating status during the reciprocating motion to attain the higher efficiency.
[0009] Preferably, one set of permanent magnet assembly is arranged at each side surface of the cylinder body, which allows the permanent magnet linear piston pump to have a greater power.
[0010] Preferably, the cylinder body includes a barrel unit and lids at two ends thereof. Sealing rings are respectively disposed between the lids at the two ends and two end faces of the barrel unit. The barrel unit and the lids at the two ends are connected with each other by a plurality of axial shanks and nuts around an outer periphery of the barrel unit. The shanks construct the coil supporting member. Accordingly, such arrangement designing the cylinder body and the coil supporting member attains a simple structure, a simple manufacturing technique and lower costs.
[0011] Preferably, ribs are disposed on edges of the cylinder body. The ribs construct the coil supporting member. The inner mounting plate and the inner magnetic body are disposed in a recess between the ribs at two sides of a same side surface of the cylinder body. Accordingly, such arrangement designing the cylinder body and the coil supporting member attains a simple structure, a simple manufacturing technique, a firm structure and high mechanical intensity.
[0012] Preferably, the cylinder body can be a prism having four to six sides, especially a quadrangular prism whose cross-section is in a rectangular shape, whereby the cylinder body in this shape is easier to be processed.
[0013] Preferably, the inner mounting plate and the outer mounting plate are made of a permeability magnetic material. A magnetizing coil is sleeved on the inner mounting plate or/and the outer mounting plate. A magnetic field line created by the magnetizing coil is formed in a closed annular shape along the inner mounting plate, the inner magnetic body, the outer magnetic body and the outer mounting plate. Accordingly, the magnetizing coil is sleeved on the inner mounting or/and the outer mounting plate, so an external magnetizing power supply in connection with the magnetizing coil magnetizes the inner magnetic body and the outer magnetic body to retrieve their intensity of magnetism when the intensity of magnetism of two magnetic bodies becomes lessened due to a long term of using the permanent magnet linear piston pump, thereby prolonging the duration of the permanent magnet linear piston pump.
[0014] The present invention is further described upon reading following preferred embodiments in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a perspective view showing a first preferred embodiment of the present invention;
[0016] FIG. 2 is a cross-sectional view showing the interior of the first preferred embodiment of the present invention;
[0017] FIG. 3 is a perspective view showing the piston body of the first preferred embodiment of the present invention;
[0018] FIG. 4 is a perspective view showing the cylinder body of the first preferred embodiment of the present invention;
[0019] FIG. 5 is a perspective view showing a second preferred embodiment of the present invention;
[0020] FIG. 6 is an exploded view showing a part of the second preferred embodiment of the present invention;
[0021] FIG. 7 is a cross-sectional view showing the interior of the second preferred embodiment of the present invention;
[0022] FIG. 8 is an enlarged view showing the “I” part of FIG. 7 ;
[0023] FIG. 9 is an enlarged view showing the “II” part of FIG. 7 ;
[0024] FIG. 10 is a schematic view showing the piston body in combination with the cylinder body of the second preferred embodiment;
[0025] FIG. 11 is a perspective view showing the cylinder body of the second preferred embodiment;
[0026] FIG. 12 is a perspective view showing a third preferred embodiment;
[0027] FIG. 13 is an exploded view showing a part of the third preferred embodiment;
[0028] FIG. 14 is a cross-sectional view showing the interior of the third preferred embodiment;
[0029] FIG. 15 is an enlarged view showing the “III” part of FIG. 14 ; and
[0030] FIG. 16 is an enlarged view showing the “IV” part of FIG. 14 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The 1 st Preferred Embodiment
[0031] Referring to FIG. 1 and FIG. 2 , a permanent magnet linear piston pump 3 of the present invention comprises a piston body 1 , a cylinder body 2 , a permanent magnet assembly 6 and an electromagnetic coil 3 . The cylinder body is in a shape of a polygonal prism, such as in a prism with four to six sides. Preferably, a quadrangular prism is adopted. As shown in FIG. 4 , this preferred embodiment has a quadrangular cylinder body 2 whose cross-section is shaped by a rectangular contour. An interior of the cylinder 2 arranges a piston cavity 201 formed by an axial columnar accommodating cavity. The piston body 1 is arranged in the piston cavity 201 by a liquid sealing movable fit mode. A cross-section of one end of the piston body 1 can be the same as the cross-section of the piston cavity 201 . This end is inserted into the piston cavity 201 by the liquid sealing movable fit mode. In this preferred embodiment, as shown in FIG. 2 and FIG. 3 , the piston body 1 is a prism whose cross-section is the same as the cross-section of the piston cavity 201 . The end of the piston body 1 is inserted into the piston cavity 201 by the liquid sealing movable fit mode; preferably, the other end thereof can arrange a supporting structure having an orientation effect. A one-way inlet valve 4 and a one-way outlet valve 5 are disposed on an end face of the piston cavity 201 opposite to an end face of a piston. A set of permanent magnet assembly 6 is disposed on at least one side surface of the cylinder body 2 . The permanent magnet assembly 6 includes an inner mounting plate 601 and an outer mounting plate 602 disposed parallel to the side surface of the cylinder body 2 . An inner magnetic body 603 and an outer magnetic body 604 are respectively disposed on opposite surfaces of the inner mounting plate 601 and the outer mounting plate 602 , whereby the permanent magnet linear piston pump has a greater power. One set of the permanent magnet assembly 6 is disposed on every side surface of the cylinder body 2 . A coil supporting member is disposed at an outside surface of the cylinder body 2 . The arrangement of the coil supporting member is to space the electromagnetic coil 3 and the outside surface of the cylinder body apart by a distance in order that the inner mounting plate 601 and the inner magnetic body 603 can be placed in this space. The electromagnetic coil 3 is axially and distributively wound around the coil supporting member into a barrel shape. Herein, the cylinder body 2 can include a barrel unit and lids at two ends thereof. Sealing rings are respectively disposed between the lids at the two ends and two end faces of the barrel unit. The barrel unit and the lids at the two ends are connected with each other by a plurality of axial shanks and nuts around an outer periphery of the barrel unit. The shanks are located at every edge of the cylinder body 2 . The shanks construct the coil supporting member. The cylinder body 2 and the coil supporting member of this arrangement are simple in structure and easier to manufacture and have lower costs although the mechanical intensity may be relatively lower. As shown in FIG. 4 , in this preferred embodiment, ribs 202 are disposed on every edge of the cylinder body 2 . The ribs 202 construct the coil supporting member. The ribs 202 can be extended throughout the full edge or extended to the part of the two ends where the electromagnetic coil 3 is wound. The ribs 202 are disposed to allow the surface of the cylinder body 2 to have a sufficient space where the inner mounting plate 601 and the inner magnetic body 603 are placed. The inner mounting plate 601 and the inner magnetic body 603 are disposed in a recess between the ribs 202 at two sides of a same side surface of the cylinder body 2 . The inner magnetic body 603 and the outer magnetic body 604 are disposed oppositely and provide contrary magnetic poles at opposite faces thereof. An interstice is formed between the inner magnetic body 603 and the outer magnetic body 604 . The interstice can be lessened possibly to satisfy the coiling of the electromagnetic coil 3 . The electromagnetic coil 3 is axially and distributively wound around the ribs 202 of every edge into a barrel type. Alternatively, it can be wound around the ribs 202 on which a pad or a bracket is disposed in advance. The electromagnetic coil 3 is disposed between the inner magnetic body 603 and the outer magnetic body 604 . The side surface of the cylinder body 2 where the permanent magnet assembly 6 is disposed forms an axial sliding slot 203 . A length of the sliding slot 203 is equal to a designed stroke length of the piston body 1 . A connecting post 101 is disposed on a side surface of the piston body 1 in a radial direction to fit in with the sliding slot 203 by a clearance fit mode. The connecting post 101 penetrates through the sliding slot 203 to be connected to the inner mounting plate 601 and the outer mounting plate 602 , thereby forming a linkage. In this preferred embodiment, through holes are respectively formed on the inner mounting plate 601 and the outer mounting plate 602 to fit in with the connecting post 101 by a clearance fit mode. The connecting post 101 penetrates through the sliding slot 203 and the through holes of the inner mounting plate 601 and the outer mounting plate 602 to be in connection with and in linkage with the inner mounting plate 601 and the outer mounting plate 602 .
The 2 nd Preferred Embodiment
[0032] To attain the higher efficiency of the permanent magnet linear piston pump, the piston body 1 is in the operating state during the reciprocating motion. In the present invention, two permanent magnet linear piston pumps are formed in the same cylinder body 2 . Referring to FIGS. 5-7 , two parts of the columnar accommodating cavity in the cylinder body 2 are disposed symmetrically. The piston body 1 is a prism whose cross-section is the same as the cross-section of the piston cavity 201 . The piston body 1 is disposed at a middle portion of the columnar accommodating cavity. Two ends of the piston body 1 are in cooperation with the two parts of the columnar accommodating cavity by the liquid sealing movable fit mode respectively, whereby the two parts of the columnar accommodating cavity are respectively defined as a first piston cavity 2011 and a second piston cavity 2012 , and the two ends of the piston body 1 are respectively defined as a first piston body 1 a and a second piston body 1 b . A first one-way inlet valve 4 a and a first one-way outlet valve 5 a are disposed on an end face of the first piston cavity 2011 opposite to an end face of the first piston body 1 a . A second one-way inlet valve 4 b and a second one-way outlet valve 5 b are disposed on an end face of the second piston cavity 2012 opposite to an end face of the second piston body 1 b . Likewise, the permanent magnet assembly 6 , as shown in FIGS. 7-9 , includes an inner mounting plate 601 and an outer mounting plate 602 disposed parallel to the side surface of the cylinder body 2 . A first inner magnetic body 603 a and a second inner magnetic body 603 b are respectively and symmetrically disposed at two opposite end faces of the inner mounting plate 601 . A first outer magnetic body 604 a and a second outer magnetic body 604 b are respectively and symmetrically disposed at two ends of the outer mounting plate 602 . A first electromagnetic coil 3 a and a second electromagnetic coil 3 b are respectively and correspondingly disposed on ribs 202 at two sides of the cylinder body 2 . Likewise, the inner mounting plate 601 and the inner magnetic body 603 are disposed in a recess between the ribs 202 at two sides of the same side surface of the cylinder body 2 . The first inner magnetic body 603 a and the first outer magnetic body 604 a at the two ends are disposed oppositely and provide contrary magnetic poles at opposite faces thereof. The second inner magnetic body 603 b and the second outer magnetic body 604 b at the two ends are disposed oppositely and provide contrary magnetic poles at opposite faces thereof. Interstices are respectively formed between the first inner magnetic body 603 a and the first outer magnetic body 604 a and between the second inner magnetic body 603 b and the second outer magnetic body 604 b . The interstice can be lessened possibly to satisfy the coiling of the electromagnetic coil 3 . The electromagnetic coil 3 is axially and distributively wound around the ribs 202 of every edge of the two ends of the cylinder body 2 into a barrel type. Alternatively, it can be wound around the ribs 202 on which a pad or a bracket is disposed in advance. The electromagnetic coils 3 are respectively disposed between the first inner magnetic body 603 a and the first outer magnetic body 604 a and between the second inner magnetic body 603 b and the second outer magnetic body 604 b . The side surface of the cylinder body 2 where the permanent magnet assembly 6 is disposed forms an axial sliding slot 203 . In this preferred embodiment, four permanent magnet assemblies 6 are respectively set on four side surfaces of the cylinder body 2 , with four sliding slots 203 formed on the four side surfaces of the cylinder body 2 respectively. A length of the sliding slot 203 is equal to a designed stroke length of the piston body 1 . Four connecting posts 101 are respectively disposed on four sides of the piston body 1 in a radial direction to fit in with the sliding slots 203 by a clearance fit mode. The connecting posts 101 penetrate through the sliding slots 203 to be connected to the inner mounting plate 601 and the outer mounting plate 602 , thereby forming a linkage. Referring to FIGS. 5-6 , this preferred embodiment forms through holes which are respectively formed on the inner mounting plate 601 and the outer mounting plate 602 to fit in with the connecting post 101 by a clearance fit mode. The connecting posts 101 penetrate through the sliding slots 203 and the through holes of the inner mounting plate 601 and the outer mounting plate 602 to be in connection with and in linkage with the inner mounting plate 601 and the outer mounting plate 602 .
The 3 rd Preferred Embodiment
[0033] To retrieve the intensity of magnetism of the inner magnetic body 603 and the outer magnetic body 604 by magnetizing and to prolong the duration of the permanent magnet linear piston pump, the permanent magnet linear piston pump of the present invention can be magnetized. Referring to FIGS. 12-16 , the remaining structure of the magnetizing permanent magnet linear piston pump is the same as the first and the second preferred embodiments. Differently, the inner mounting plate 601 and the outer mounting plate 602 are made of a permeability magnetic material. A magnetizing coil 7 is sleeved on the inner mounting plate 601 or the outer mounting plate 602 . To enhance the intensity of the recharging magnetic field, the magnetizing coil 7 of this embodiment is sleeved on the inner mounting plate 601 and the outer mounting plate 602 . The magnetizing coil 7 can be wound around a coil frame 8 of a “□” shape at first. Then, the inner mounting plate 601 or the outer mounting plate 602 can penetrate through the center of the coil frame 8 . The coil frame 8 is fixed onto the cylinder body 2 . A magnetic field line created by the magnetizing coil 7 is formed in a closed annular shape along the inner mounting plate 601 , the inner magnetic body 603 , the outer magnetic body 604 and the outer mounting plate 602 .
[0034] From the above preferred embodiments, the one-way inlet valve 4 and the one-way outlet valve 5 can be designed by using a diaphragm structure or by disposing a steel ball and a compression spring in the valve cavity. These arrangements can all satisfy the requirements. | A permanent magnet linear piston pump comprises a piston body, a cylinder body, a permanent magnet assembly and an electromagnetic coil. The piston body is arranged in a piston cavity by a liquid sealing movable fit mode. An inner magnetic body and an outer magnetic body are disposed on at least one side surface of the cylinder body. An electromagnetic coil is axially and distributively wound around a coil supporting member which is disposed at an outside surface of the cylinder body. The electromagnetic coil is disposed between the inner magnetic body and the outer magnetic body. By the above structure, the pump needs not subject the electromagnetic coil to a sealing treatment, thereby attaining a simple structure, more convenient manufacture, lower costs, a reliable operation and convenient maintenance. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a sealed-type optical information recording medium.
It is required that an adhesive agent for sealing a disk-type information recording medium have no adverse effects on the recording materials for the medium to be sealed, for instance, by a by-product formed during the hardening of the adhesive agent, and the adhesive agent not contain a solvent. For such a purpose, an epoxy adhesive agent is usually employed. However, an epoxy adhesive agent has the shortcomings that when a plastic substrate is employed, the adhesive agent deforms the substrate upon heat application for the hardening of the adhesive agent, and a long time is required for the hardening. Recently, a room-temperature-hardening type epoxy adhesive agent is proposed, which becomes hard at room temperature. However, it also has the shortcoming that a long time is required for the hardening.
Under such circumstances, an ultra-violet-ray hardening type adhesive agent attracts attention. This adhesive agent appears promising because it neither produces any adverse by-products during the hardening nor contains any solvent therein. In the case of this adhesive agent, the hardening is carried out by a radical polymerization reaction and the radicals present in the adhesive agent are consumed by oxgen contained in the air, so that it has the shortcoming that a long time is required for the hardening of the surface when applied. In particular, when this adhesive agent is used in an air-sandwich-type sealed disk, the surface of the applied adhesive agent in the sealed inner portion does not become hard enough so that unreacted monomer components evaporate form the sealed inner portion, by which the recording layer is adversely affected. As a countermeasure for this problem, it is proposed to eliminate oxygen from the atmosphere for the hardening process. Specifically, a method of hardening the adhesive agent in an atmosphere of nitrogen is proposed. However, this method is not necessarily suitable for mass production, because a large-scale facility is required.
In a sealed type information recording medium including a recording layer at an adhesion portion, it is known that the adhesion strength between the recording material and the substrate is not so strong that there is the risk that the recording layer eventually peels off the substrate surface.
Further, a variety of organic dyes have been developed as the recording material. Some of them allow easy formation of a recording layer, for example, by coating the dye dissolved in a solvent. This is one of the advantages of the organic dyes over other materials. When an organic dye is dissolved in a solvent and is coated on a substrate, spin coating is most suitable for accurate film formation coating. The spin coating, however, has the shortcoming that the masking for not forming a recording layer in the adhesion portion is extremely difficult. Therefore, if a recording layer in the adhesion portion is removed prior to the coating of an adhesive agent, it is possible to secure sufficient adhesion strength between the recording layer and the substrate. In this case, dust is formed in the course of the removing of the recording layer, by which defective recording mediums are apt to be produced.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a sealed-type optical information recording medium with its sealing reliability improved.
The above object of the present invention is attained by use of an adhesive agent comprising a compound having formula (I) and a compound having formula (II), by which the surface hardening of the adhesive agent is improved, and the deterioration of the recoridng material is minimized, respectively. In order to improve the adhesive strength, a compound having formula (III) can also be added to the adhesive agent. ##STR6## wherein φ represents ##STR7## (l=0 or 1) or ##STR8## in which R represents a methyl group or an ethyl group, m is an integer of 1 to 4, and n is an integer of 2 to 4. ##STR9## wherein n is an integer of 4 to 8. ##STR10## wherein L represents --CH 2 CH 2 O m (m=1 to 4) or --CH 2 C(OH)HCH 2 O--, R 1 represents --C n H 2n+1 (n=4 to 12), R 2 reprsents Cl or Br (n=0, 1 or 2)
In an embodiment of an optical information recording medium according to the present invention, a pair of disk-shaped substrates, with a recording layer comprising an organic dye being formed on one side of at least one substrate, are fixed to each other in a concentric configuration, through or without through a spacer such as an inner circumferential spacer and an outer circumferential spacer, in such a manner that the above-mentioned recording layer comes between the substrates, and the above-mentioned adhesive agent is used for the sealing thereof.
BRIEF DESCRIPTION OF THE DRAWING
The single FIGURE is a schematic sectional view of an optical recording medium according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
It is preferable that the adhesive agent for use in the present invention comprises the compound of formula (I) in an amount ranging from 40 wt.% to 70 wt.%, and the compound of formula (II) in an amount ranging from 10 wt% to 30 wt.%. When the compound of formula (III) is also employed, it is preferable that the amount be in the range of 10 wt.% to 30 wt.% in the adhesive agent.
With reference to the accompanying drawing, a sealed-type optical information recording medium according to the present invention will now be explained.
Each of a pair of disk-shaped substrates 1,1 is made of, for example, a transparent plastic plate. In each substrate 1, a fitting hole 2 is formed at the center thereof. One of the substrates 1,1 includes a recording layer 3 comprising an organic dye at one surface thereof. The substrates 1,1 are disposed in a concentric configuration, with an inner circumferential spacer 4 and an outer circumferential spacer 5 interposed therebetween, in such a fashion that the recording layer 3 comes inside so that a space 6 is formed between the recording layer 3 and the substrate 1 as shown in the FIGURE. The adhesive agent for use in the present invention is applied at a portion 7 for fixing the pair of the substrates 1,1.
The present invention is not necessarily restricted to the configuration shown in the FIGURE. For instance, the recording layer can be formed on both substrates 1,1 at one side of each thereof.
The materials and the layers of which the optical information recording medium according to the present invention is composed will now be specifically explained. In addition to the recording layer, an undercoat layer can be interposed between the substrate and the recording layer.
(1) Substrate
When recording and reproduction of information are performed on the substrate side, it is necessary that the substrate be transparent to the laser beams employed.
As the material for the substrate, plastics such as polyester, acrylic resin, polycarbonate, polyamide, polyolefine resin, phenolic resin, epoxy resin and polyimide, glass, ceramics and metals can be employed. On the surface of the substrate, preformats for address signal, and pregrooves as guide grooves can be formed. The substrate can be molded either by the photopolymer method or by the injection molding method.
(2) Recording Layer
The recording layer can record information by some optical changes in the layer, which may be caused by the recording layer being exposed to laser beams. The recording layer comprises as the main components an organic dye, for example, a polymethine dye, which will be described in detail later. Representative examples of the polymethine dye are a cyanine dye, a merocyanine dye, a croconium dye and a pyrylium dye.
In order to improve the recording characteristics and stability of the recording layer, two or more dyes can be employed in combination. Furthermore, in addition to the above dyestuffs, the following dyes can be employed: Phthalocyanine dyes, tetrahydrocholine dyes, dioxazine dyes, triphenothiazine dyes, triphenothiazine dyes, phenanthrene dyes, anthraquinone (Indanthrene) dyes, xanthene dyes, triphenylmethane dyes, and azulene dyes.
Metals such as In, Sn, Te, Bi, Al, Se, Ag and Cu, and metal compounds such as TeO 2 and SnO can be dispersed in the recording layer or made into a layer to form on the recording layer. Further, other polymeric materials, stabilizers for preservation (for example, metal complexes, and phenolic compounds), dispersing agent, agent for making incombustible, unguent, charging prevention agent, and plasticizer can be added to the recording layer.
The recording layer can be formed on the substrate by any of the conventional methods such as vacuum evaporation, sputtering, CVD (chemical vapor deposition) or solution coating. Of these methods, the solution coating method is most preferable for forming the recording layer.
When the solution coating method is performed, a polymethine dye and other components are dissolved in an organic solvent such as alcohol, ketone, amide, ether, sulfoxide, ester, halogenated aliphatic hydrocarbon, and aromatic hydrocarbon to prepare a solution. This solution is coated on a substrate by a conventional coating method, such as spray coating, spin coating, dip coating, blade coating and roller coating.
It is preferable that the thickness of the recording layer be in the range of 100 Å to 10 μm, more preferably in the range of 200 Å to 2 μm.
(3) Polymethine Dye
The following are representative polymethine dyes for use in the present invention:
(a) Cyanine Dye ##STR11##
In the above formulas (I)-(IV), A, B, D and E each represent a substituted or unsubstituted aryl group; R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 may be same or different, and each represents a hydrogen atom, a halogen atom or an alkyl group; Y represents a dihydric residue having an atomic group required for completing a pentacyclic ring or a hexacyclic ring; R 8 and R 9 may be same or different, and each represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aralkyl group or alkenyl group; Z 1 and Z 2 each represent an atomic group required for completing a substituted or unsubstituted heterocyclic ring; Z 3 represents an atomic group required for completing a substituted or unsubstituted pentacyclic ring or hexacyclic ring, and said pentacyclic ring or hexacyclic ring may be condensed with an aromatic ring; R 10 represents a hydrogen atom or a halogen atom; R 11 and R 12 each represent a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, an alkyl group, or a substituted or unsubstituted aryl group or acryloxy; and l, m and n each represent 0 or 1. Y represents an acid anion.
__________________________________________________________________________Compound No. A B D E__________________________________________________________________________Formula (I)-1 ##STR12## ##STR13## ##STR14## ##STR15##Formula (I)-2 " " " "Formula (I)-3 ##STR16## ##STR17## ##STR18## ##STR19##Formula (I)-4 " ##STR20## " ##STR21##Formula (I)-5 ##STR22## ##STR23## ##STR24## ##STR25##Formula (I)-6 ##STR26## ##STR27## ##STR28## ##STR29##Formula (I)-7 ##STR30## ##STR31## " "Formula (II)-1 " " " "Formula (II)-2 " ##STR32## " ##STR33##__________________________________________________________________________ Compound No. R.sup.1 R.sup.2 R.sup.3 R.sup.4 R.sup.5 Y X.sup.⊖__________________________________________________________________________ Formula (I)-1 H H H H H ##STR34## ClO.sub.4 Formula (I)-2 H H H H Cl " ClO.sub.4 Formula (I)-3 H H H H H ##STR35## ClO.sub.4 Formula (I)-4 H H H H H ##STR36## ClO.sub.4 Formula (I)-5 H H H H Br ##STR37## ClO.sub.4 Formula (I)-6 H H H H H ##STR38## ##STR39## Formula (I)-7 H H H H Cl " " R.sup.6 R.sup.7 Formula (II)-1 H H H H Cl H H " Formula (II)-2 H H H H Cl ##STR40## H ClO.sub.4__________________________________________________________________________
__________________________________________________________________________ (III)FormulaNo.poundCom- ##STR41## ##STR42## Z.sup.3 R.sup.8 R.sup.9 R.sup.10 l X.sup.⊖__________________________________________________________________________ ##STR43## ##STR44## ##STR45## CH.sub.3 CH.sub.3 H 0 I2 ##STR46## ##STR47## ##STR48## C.sub.4 H.sub.9 C.sub.4 H.sub.9 Cl 0 Cl3 ##STR49## ##STR50## ##STR51## C.sub.2 H.sub.5 C.sub.2 H.sub.5 H 1 I4 ##STR52## ##STR53## ##STR54## C.sub.2 H.sub.5 C.sub.2 H.sub.5 H 1 I5 ##STR55## ##STR56## ##STR57## C.sub.2 H.sub.5 C.sub.2 H.sub.5 H 1 I6 ##STR58## ##STR59## ##STR60## C.sub.2 H.sub.5 C.sub.2 H.sub.5 H 1 I7 ##STR61## ##STR62## ##STR63## C.sub.2 H.sub.5 C.sub.2 H.sub.5 Cl 1 I8 ##STR64## ##STR65## ##STR66## C.sub.2 H.sub.5 C.sub.2 H.sub.5 H 1 ##STR67##9 ##STR68## ##STR69## ##STR70## CH.sub.3 CH.sub.3 Br 1 SO.sub.4CH.sub.310 ##STR71## ##STR72## ##STR73## C.sub.4 H.sub.9 C.sub.4 H.sub.9 H 1 SO.sub.4C.sub.2__________________________________________________________________________ H.sub.5
__________________________________________________________________________ Compound No. ##STR74## ##STR75## R.sup.8 R.sup.9 R.sup.12 R.sup.11 l X.sup.⊖__________________________________________________________________________Formula (IV) ##STR76## ##STR77## C.sub.2 H.sub.5 C.sub.2 H.sub.5 H H 1 Cl2 ##STR78## ##STR79## CH.sub.3 CH.sub.3 H H 1 Cl3 ##STR80## ##STR81## C.sub.5 H.sub.7 C.sub.5 H.sub.7 H H 1 Cl4 ##STR82## ##STR83## C.sub.4 H.sub.9 C.sub.4 H.sub.9 H H 1 Cl5 ##STR84## ##STR85## CH.sub.3 CH.sub.3 H H 1 I6 ##STR86## ##STR87## CH.sub.3 CH.sub.3 H H 1 I7 ##STR88## ##STR89## CH.sub.3 CH.sub. 3 H H 1 I8 ##STR90## ##STR91## C.sub.2 H.sub.5 C.sub.2 H.sub.5 H H 1 ##STR92##9 ##STR93## ##STR94## C.sub.3 H.sub.7 C.sub.3 H.sub.7 H H 1 C.sub.2 H.sub.5SO.sub.4 410 ##STR95## ##STR96## CH.sub.3 CH.sub.3 H Cl 1 CH.sub.3 SO.sub.411 ##STR97## ##STR98## CH.sub.3 CH.sub.3 H Cl 0 ClO.sub.4__________________________________________________________________________
(b) Merocyanine Dye ##STR99## wherein A represents the following rings, the benzene ring and naphthyl ring of which may have a substituent: ##STR100## and the like; ##STR101## represents the following rings; ##STR102## and n represents 1 or 2.
(c) Pyrylium Dye ##STR103##
In the above formulas (VI) and (VII), X, X 1 and X 2 each represent a sulfur atom, an oxygen atom or a selenium atom; Z and Z 1 each represent a hydrocarbon group comprising an atomic group required for completing pyrylium, thiopyrylium, selenapyrylium, benzopyrylium, benzothiopyrylium, benzoselenapyrylium, naphthopyrylium, naphthothiopyrylium or naphthoselenapyrylium which may have been substituted; Z 2 represents a hydrocarbon group comprising an atomic group required for completing pyran, thiopyran, selenapyran, benzopyran, benzothiopyran, benzoselenapyran, naphthopyran, naphthothiopyran or naphthoselenapyran which may have been substituted; R 1 , R 2 , R 3 and R 4 each represent a hydrogen atom, a substituted or unsubstutued alkyl group or a substituted or unsubstituted aryl group; R 5 , R 6 and R 7 each represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group; m and l each represent 1 or 2; and n represents 0, 1 or 2. Y represents an acid anion.
(4) Undercoat Layer
An undercoat layer is employed for the following purposes: (a) improvement of the adhesiveness of the recording layer to the substrate, (b) protection of the recording layer from water and gases, (c) improvement of the preservability and stability of the recording layer, (d) improvement of the reflection ratio of the recording layer, (e) protection of the substrate from solvents, and (f) for formation of pregrooves in the recording layer.
For the purpose (a), a variety of polymeric materials such as ionomer resin, polyamide resin, vinyl resin, natural polymeric material, silicone and liquid rubber, and silane coupling agent can be employed.
For the purposes (b) and (c), in addition to the above polymeric materials in (a), inorganic compounds such as SiO 2 , MgF 2 , SiO, TiO 2 , ZnO, TiN and SiN, and metals and metalloids such as Zn, Cu, S, Ni, Cr, Ge, Se, Au, Ag and Al can be employed.
For the purpose (d), metals such as Ag and Al, and dyes having metallic luster such as methine dye and xanthene dye can be employed.
The present invention will now be explained in more detail with reference to the following examples. These examples are given for an illustrative purpose and therefore the present invention will not be restricted to these examples.
EXAMPLE 1
A pair of disk-shaped polymethyl methacrylate substrates having a diameter of 200 mm and a thickness of 1 mm were prepared. A pregroove was formed in one of the substrates by the conventional photopolymer method.
A 1,2-dichloroethane solution of the following dye with a concentration thereof being 0.7 wt.% was coated on the substrate by spin coating at 600 rpm, so that a recording layer was formed thereon. ##STR104##
By use of an inner circumferential spacer and an outer circumferential spacer each having a thickness of 1 mm, and an adhesive agent prepared in the following formulation, an optical information recording medium No. 1 of a sealed disk-type according to the present invention was fabricated in the same configuration as shown in the FIGURE. In the formulation give below, A represents a moiety of ##STR105##
______________________________________ Parts by weight______________________________________ 60ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2 ) .sub.6OCH.sub.2 C(OH)HCH.sub.2A 20 ##STR106## 202,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The thus fabricated optical information recording medium was allowed to stand at 60° C., 90% R.H. for 1,000 hours and the recording characteristics thereof were measured and compared with the initial values thereof. The results are shown in Table 1.
EXAMPLE 2
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby an optical information recording medium No. 2 according to the present invention was fabricated.
______________________________________ Parts by weight______________________________________ ##STR107## 65ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2) .sub.6OCH.sub.2 C(OH)HCH.sub.2A 20 ##STR108## 152,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The result are shown in Table 1.
EXAMPLE 3
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby an optical information recording medium No. 3 according to the present invention was fabricated.
______________________________________ Parts by weight______________________________________ ##STR109## 50ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2 ) .sub.4OCH.sub.2 C(OH)HCH.sub.2A 25 ##STR110## 252,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The results are shown in Table 1.
EXAMPLE 4
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby an optical information recording medium No. 4 according to the present invention was fabricated.
______________________________________ Parts by weight______________________________________ ##STR111## 60ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2 ) .sub.6OCH.sub.2 C(OH)HCH.sub.2A 30 ##STR112## 102,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The results are shown in Table 1.
EXAMPLE 5
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby an optical information recording medium No. 5 according to the present invention was fabricated.
______________________________________ Parts by weight______________________________________ ##STR113## 70ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2 ) .sub.6OCH.sub.2 C(OH)HCH.sub.2A 302,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium wer measured in the same manner as in Example 1. The results are shown in Table 1.
EXAMPLE 6
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby an optical information recording medium No. 6 according to the present invention was fabricated.
______________________________________ Parts by weight______________________________________ ##STR114## 65ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2 ) .sub.6OCH.sub.2 C(OH)HCH.sub.2A 20 ##STR115## 152,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The results are shown in Table 1.
EXAMPLE 7
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby an optical information recording medium No. 7 according to the present invention was fabricated.
______________________________________ Parts by weight______________________________________ ##STR116## 60ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2 ) .sub.4OCH.sub.2 C(OH)HCH.sub.2A 20 ##STR117## 202,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The results are shown in Table 1.
EXAMPLE 8
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby an optical information recording medium No. 8 according to the present invention was fabricated.
______________________________________ Parts by weight______________________________________ ##STR118## 50ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2) .sub.6OCH.sub.2 C(OH)HCH.sub.2A 20 ##STR119## 302,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The results are shown in Table 1.
EXAMPLE 9
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby an optical information recording medium No. 9 according to the present invention was fabricated.
______________________________________ Parts by weight______________________________________ ##STR120## 60ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2) .sub.8OCH.sub.2 C(OH)HCH.sub.2A 20 ##STR121## 202,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The results are shown in Table 1.
EXAMPLE 10
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby an optical information recording medium No. 10 according to the present invention was fabricated.
______________________________________ Parts by weight______________________________________ ##STR122## 70ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2) .sub.4OCH.sub.2 C(OH)HCH.sub.2A 302,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The results are shown in Table 1.
COMPARATIVE EXAMPLE 1
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby a comparative optical information recording medium No. 1 was fabricated.
______________________________________ Parts by weight______________________________________ ##STR123## 60ACH.sub.2 C(OH)HCH.sub.2 O(CH.sub.2 ) .sub.4OCH.sub.2 C(OH)HCH.sub.2A 20 ##STR124## 202,2-dimethoxy-2-phenylacetophenone 2(photopolymerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The results are shown in Table 1.
COMPARATIVE EXAMPLE 2
Example 1 was repeated except that the formulation of the adhesive agent employed in Example 1 was replaced by the following formulation, whereby a comparative optical information recording medium No. 2 was fabricated.
______________________________________ Parts by weight______________________________________ ##STR125## 55ACH.sub.2 ) .sub.3CCH.sub.2 OH 25 ##STR126## 202,2-dimethoxy-2-phenylacetophenone 2(photopolmerization initiator)______________________________________
The recording characteristics of the above optical information recording medium were measured in the same manner as in Example 1. The results are shown in Table 1.
TABLE 1__________________________________________________________________________Initial Values After 1000 hrs at 60° C., 90% R.H.Reflection C/N Repeated* Reflection C/N Repeated*Ratio (%) (dB) Reproduction Ratio (%) (dB) Reproduction__________________________________________________________________________Example 1 26.0 53 over 1 mil. 24.2 51 over 1 mil.Example 2 26.0 53 over 1 mil. 24.5 51 over 1 mil.Example 3 26.0 53 over 1 mil. 23.8 50 over 1 mil.Example 4 26.0 53 over 1 mil. 24.0 51 over 1 mil.Example 5 26.0 53 over 1 mil. 24.5 51 over 1 mil.Example 6 26.0 53 over 1 mil. 24.5 52 over 1 mil.Example 7 26.0 53 over 1 mil. 24.0 51 over 1 mil.Example 8 26.0 53 over 1 mil. 24.2 51 over 1 mil.Example 9 26.0 53 over 1 mil. 23.5 50 over 1 mil.Example 10 26.0 53 over 1 mil. 24.0 51 over 1 mil.Comp. 26.0 53 450,000 19 47 upto 10,000Example 1Comp. 26.0 53 450,000 Peeled off during storageExample 2__________________________________________________________________________ *In the above table, the repeated reproduction means the number of reproductions before the error ratio began to increase in the course of continuously repeated reproduction using the same track. | An optical information recording medium comprising a pair of substrates, with a recording layer comprising an organic dye being formed on one side of at least one substrate, fixed to each other through or without through a spacer and by an adhesive agent, in such a manner that the recording layer comes between the substrates, the adhesive agent comprising a compound of formula (I), ##STR1## wherein φ represents ##STR2## (l=0 or 1) or ##STR3## in which R represents a methyl group or an ethyl group, m is an integer of 1 to 4, and n is an integer of 2 to 4; and a compound of formula (II), ##STR4## wherein n is an integer of 4 to 8, to which a compound of formula (III) may be added, ##STR5## wherein L represents --CH 2 CH 2 O m (m=1 to 4) or --CH 2 C(OH)HCH 2 O--, R 1 represents --C n H 2n+1 (n=4 to 12), R 2 represents Cl or Br (n=0, 1 or 2). | 8 |
This is a continuation, of application serial no. 071,865 (now abandoned) filed Sept. 4, 1979.
BACKGROUND OF THE INVENTION
The present invention relates to a push-pull amplifier, and more particularly to an amplifier circuit which makes it possible to automatically adjust a biasing current.
FIG. 1 is a circuit diagram of a conventional push-pull amplifier.
Referring to FIG. 1, Q 1 and Q 2 denote NPN and PNP transistors, respectively, R 1 and R 2 resistors for stabilizing a biasing current I B , Z L load including reactance, V BS /2 biasing power supply circuit, and +V CC and -V CC DC voltage power supplies, respectively.
If the input voltage e i is 0 volts, the electric potential at the output terminal P is approximately 0 volts. Since no load current I L flows, only a biasing current I B ≃[V BS -(V BE1 +V BE2 )]/(R 1 +R 2 ) flows between transistors Q 1 and Q 2 .
However, assuming that the input voltage e i varies towards positive-going swing, the load current I L flows in the direction of the solid line shown in FIG. 1 from the transistor Q 1 . Due to the voltage drop I L R 1 across the resistor R 1 , the biasing current I B decreases.
If the input voltage e i further increases and I L R 1 ≧V BS -(V BE1 +V BE2 ) holds, the transistor Q 2 will be completely cut off.
In this condition, the push-pull circuit becomes equal to an emitter-follower circuit in which only transistor Q 1 is used, resulting in deterioration in the transient characteristics if the load Z L includes reactance.
On the other hand, when the input voltage e i varies towards negative-going swing, the load current I' L flows in the direction of the broken line in FIG. 1 to the transistor Q 2 .
Accordingly, when I' L R 2 ≧V BS -(V BE1 +V BE2 ) holds, transistor Q 1 is completely cut off, resulting in the same phenomenon.
In order to prevent this the push-pull circuit may, for instance, be greately biased to effect class "A" amplification. Thus, if the circuit is designed so that a biasing current I B flows, serving as an idling current whose value is of the order of magnitude of the load current I L , some improvement may be expected.
However, with this conventional circuit, a low efficiency of amplification will be obtained. Moreover, in order not to allow transistors Q 1 and Q 2 to be completely cut off, the minimum impedance value of the load is limited to a predetermined value. Therefore, this method is not very satisfactory.
SUMMARY OF THE INVENTION
With the above in mind, an object of the present invention is to provide a push-pull amplifier circuit which makes it possible to keep a biasing current constant independent of the load current.
Another object of the present invention is to provide a push-pull amplifier circuit including a feedback loop for automatically adjusting a biasing current to obtain good transfer characteristics.
A further object of the present invention is to provide a push-pull amplifier circuit wherein the feedback loop mentioned above is designed so as to have a gain of unity to improve linearity of the transfer characteristics of the push-pull amplifier.
According to the present invention, there is provided an amplifier comprising a push-pull amplifier connected to a biasing power supply circuit for supplying a biasing current through a first diode to the push-pull amplifier, and a DC amplifier connected to an input of the push-pull amplifier via a second diode connected with the first diode in logical-sum fashion so as to balance the half potential of the biasing power supply circuit with the potential at the output of the push-pull amplifier, thereby maintaining the biasing current constant independent of the load current flowing during rated operation of the push-pull amplifier.
Further in accordance with the present invention, there is provided an amplifier arrangement which comprises a first and a second biasing power supply circuits, a push-pull amplifier comprising a pair of transistors, a DC amplifier having a noninverting input terminal connected to a junction point which one half of a predetermined potential fed from the first biasing power supply circuit is applied and having an inverting input terminal connected to a feedback loop through which the output of the amplifier is fedback, a second biasing power supply circuit having a junction point at which the output of the DC amplifier is applied, and means responsive to an output of the DC amplifier for applying either of the first and second predetermined potentials fed from the first and second biasing circuits in accordance with the amount of feedback from the output of the push-pull amplifier to produce an output signal is applied to each base of the push-pull transistors so as to balance the half potential of the first biasing power supply circuit with the potential at the output of the push-pull amplifier.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of a push-pull amplifier circuit according to the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a circuit diagram of a conventional push-pull amplifier circuit,
FIG. 2 is a circuit diagram of a push-pull amplifier circuit according to the present invention,
FIG. 3 is a graph illustrating characteristics of load current versus biasing electric potential according to the present invention,
FIG. 4 is a graph illustrating load current versus biasing electric current characteristics and transfer characteristics according to the present invention,
FIG. 5 is a graph illustrating load current versus biasing current characteristics and transfer characteristics according to conventional push-pull amplifier circuit,
FIG. 6 is a circuit diagram of a modification of a push-pull amplifier circuit according to the present invention,
FIG. 7 is a circuit diagram of another embodiment of a push-pull amplifier circuit according to the present invention, and
FIG. 8 is a circuit diagram wherein a push-pull circuit according to the present invention is applied to a high fidelity amplifier.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG., 2, Q' 1 and Q' 2 denote NPN and PNP transistors, respectively, R' 1 and R' 2 are resistors for stabilizing a biasing current I' B , Z' L is a load including reactance, V' BS /2 is a biasing power supply circuit, and +V' CC and -V' CC respectively, are positive and negative DC power supplies. A and V" BS /2 denote a DC amplifier and biasing power supply circuits, respectively, which are newly added in the present invention.
D 1 , D 2 , D 3 , and D 4 denote diodes for preventing reverse direction current in the biasing power supply circuits and for applying either of the output of the biasing circuit already provided in the prior art circuit and the output of the biasing circuit newly added according to the present invention in accordance with the amount of feedback from the output of the push-pull amplifier.
Now, let the gain of the DC amplifier be designated by A. Then, suppose that settings are made such that the offset voltage is zero, biasing voltages V' BS /2 and V" BS /2 are equal, the emitter resistances R' 1 and R' 2 of the transistors Q' 1 and Q' 2 equal each other, the forward voltages V D across diodes D 1 , D 2 , D 3 and D 4 equal each other, and the forward voltages V BET between base and emitter electrodes of the transistors Q' 1 and Q' 2 equal each other.
Electric potentials e a and e o at output terminal C of the DC amplifier and at output terminal p' of the push-pull amplifier are determined from the input voltage e i and the load current I" L as follows; ##EQU1## If the gain of the DC amplifier is sufficiently large, equations (1) and (2) may be regarded as the following equations (1)' and (2)', respectively:
e.sub.a ≃e.sub.i +R'.sub.1 I".sub.L (1)'
e.sub.o ≃e.sub.i (2)'
Equation (1)' shows that the output e a of the DC amplifier varies according to increase and decrease of the load current, and the current flow direction.
Equation (2)' shows that the output voltage e o of the push-pull amplifier is independent of increases and decreases of the load current.
The concept expressed by the above equations (1), (2), (1)' and (2)' is essential for the present invention. Accordingly, it is important to refer to details of the derivation thereof for a better understanding of the present invention.
In FIG. 2, a non-inverting input terminal and an inverting input terminal of the differential amplifier are connected to the input voltage e i and the output terminal p' of the push-pull amplifier, respectively. Accordingly, assuming that the gain of the differential amplifier is A, the output voltage e a is expressed by the following equation;
e.sub.a =(e.sub.i -e.sub.o)A (i)
Suppose that e a >e i , the diode D 2 becomes conductive, and D 1 becomes nonconductive, then D 4 becomes conductive, and D 3 becomes nonconductive. The following equations are derived on the basis of this supposition.
Calculating the output voltage e a of the differential amplifier from the path through the diode D 2 to the load Z' L , the following equation is obtained.
e.sub.a =e.sub.o +R'.sub.1 (I'.sub.B +I".sub.L)+V.sub.BET +V.sub.D -V".sub.BS /2 (ii)
Calculating the biasing current I' B flowing in transistors Q' 1 and Q' 2 from the path through the diode D 4 to the load Z' L , the following equation is obtained. ##EQU2## Substitution of equation (iii) into equation (ii) gives: ##EQU3## Taking into account R' 1 =R' 2 , and V' BS /2=V" BS /2
e.sub.a =2e.sub.o -e.sub.i +R'.sub.1 I".sub.L (iv)
is obtained. Elimination of e a from equations (i) and (iv) gives: ##EQU4## Similarly, elimination of e o from equations (1) and (iv) gives: ##EQU5## In the above calculation, it was assumed that e a >e i , but if assuming that e a <e i , the diode D 2 becomes nonconductive, the diode D 1 becomes conductive, the diode D 4 becomes nonconductive, and D 3 becomes conductive. From the path through the diode D 3 to the load Z' L , a calculation of the output voltage e a of the differential amplifier is carried out to obtain the following equation similar to the equation (ii),
e.sub.a =e.sub.o -R'.sub.2 (I'.sub.B -I".sub.L)-V.sub.BET -V.sub.D +V".sub.BS /2 (ii)'
Furthermore, from the path through the diode D 1 to the load Z' L , a calculation of the biasing current I' B flowing in transistors Q' 1 and Q' 2 is carried out to obtain the following equation, ##EQU6## Substitution of equation (iii)' into equation (ii)', in consideration of R' 1 =R' 2 and V' BS /2=V" BS /2, gives
e.sub.a =2e.sub.o -e.sub.i +R'.sub.1 I".sub.L (iv)'
which is the same as equation (iv). Similarly, from equations (i) and (iv)' e a and e o are obtained with the same formulation as equations (1) and (2). Accordingly, it is understood that equations (1) and (2) always hold irrespective of the signs of the terms. As A goes to infinity, equations (1) and (2) become
e.sub.a ≃e.sub.i +R'.sub.1 I".sub.L (1)'
e.sub.o ≃e.sub.i (2)'
Thus, equations (1)' and (2)' are obtained.
Suppose that the base electrode voltages of the transistors Q' 1 , Q' 2 with respect to ground are V BG1 , and V BG2 , respectively.
The values of the voltages V BG1 and V BG2 are classified into the following cases, in accordance with the states of the diodes D 1 to D 4 , and the polarity of the load current I" L
(1) I" L ≧O (when I" L flows in the direction of the arrow in FIG. 2.)
V.sub.BG1 =V'.sub.BS /2+e.sub.i +R'.sub.1 I".sub.L -V.sub.D (3)
V.sub.BG2 =V.sub.BS /2+e.sub.i +V.sub.D (4)
(2) I" L <O (when I" L flows in the direction opposite to the arrow in FIG. 2.)
V.sub.BG1 =V'.sub.BS /2+e.sub.i -V.sub.D (3)'
V.sub.BG2 =-V'.sub.BS /2+e.sub.i +R'.sub.1 I".sub.L +V.sub.D (4)'
In equation (3), diode D 2 is conducting but the diode D 1 is cut off because of the inverse bias.
In equation (4), diode D 4 is conducting but the diode D 3 is cut off because of the reverse bias.
On the other hand, in equation (3)' the diode D 1 is conducting, but the diode D 2 is cut off and in equation (4)' the diode D 3 is conducting, but the diode D 4 is cut off.
Thus, it is possible to apply either of the output of each biasing circuit, thereby maintaining a biasing current constant independent of the load current.
FIG. 3 is a graph of the voltages V BG1 and V BG2 against the load current I" L .
In FIG. 3, I" L and voltages are abscissas and ordinates, respectively, and the input voltage e i is indicated on the V axis.
The graph of the voltages V BG1 and V BG2 has a rotational symmetry with respect to the value e i on the V axis. When the transistor Q' 1 becomes operative so that load current I" L flows in the positive direction, the voltage V BG1 increases by the voltage drop occurring across the emitter resistor R' 1 of the transistor Q' 1 , thereby keeping the potential level of the output terminal P equal to that of e i .
On the contrary, when the transistor Q' 2 becomes operative so that the load current I" L flows in the negative direction, V BG2 is lowered by the voltage drop produced across the emitter resistance R' 2 of the transistor Q' 2 , thereby keeping the potential e o at the output P of the push-pull circuit equal to that of e i .
Thus, a constant biasing voltage is applied to whichever transistor is not conducting.
That is, constant biasing voltage potentials V' BS /2-V D and -V' BS /2+V D are applied between the bases of transistors Q' 1 and Q' 2 , respectively, and the output of the push-pull circuit. Accordingly, it is possible to maintain a constant bias current I' B =[V' BS α/2-(V D +V BET )]/R' 1 between the emitter electrodes of the transistors Q' 1 and Q' 2 .
It will now be shown that, according to the present invention, irrespective of the value of the load current I" L , neither of the transistors Q' 1 and Q' 2 constituting the push-pull amplifier are ever put in the nonconducting state.
FIG. 4 is a graph illustrating the relationship between the load current I" L and the emitter currents of the transistors Q' 1 and Q' 2 according to the present invention.
FIG. 5 shows a similar relationship according to a conventional circuit.
As will be seen from FIG. 4, a predetermined bias current I' B flows in the transistor which is not conducting.
On the contrary, in the conventional circuit shown in FIG. 5, a bias current flows only when the load current I L is in the vicinity of zero. When the load current I L increases or decreases, one of the transistors Q 1 or Q 2 will be cut off.
Another drawback of the conventional circuit is that the transfer characteristic of the push-pull amplifier has curved portion where the load current is in the vicinity of zero, as shown by a broken line in FIG. 5, while, as shown by a broken line in FIG. 4, the transfer characteristic of a push-pull circuit according to the present invention has good linearity since a large negative feedback is supplied to the push-pull circuit.
FIG. 6 shows a circuit which is a modified version of the present invention, using transistors to provide the selecting of either of the outputs of each biasing circuit and push-pull operation, in place of the diodes used in the basic circuit shown in FIG. 2.
In FIG. 6, Q 3 and Q 4 denote NPN transistors, Q 5 and Q 6 PNP transistors, R" 1 , R" 2 resistors for stabilizing a bias current, Z" L a load including reactance, V BB /2 bias power supply circuit, +V c and -V c plus and minus power supplies, and A' a DC amplifier.
The basic operation is the same as that of the basic circuit shown in FIG. 2, but by making judicious use of inverse voltages between the base and emitter electrodes of transistors Q 3 , Q 4 , Q 5 and Q 6 , the same effect as with the diodes in the basic circuit is obtained. It is to be noted that these transistors also effect the push-pull operation.
FIG. 7 shows a circuit in which performance is improved in practice wherein a sum output between common emitter electrodes of the transistors is obtained similarly to the FIG. 6 circuit, but the output of the common emitter is not directly connected to the load, but it is Darlington-connected to a push-pull amplifier comprising separate transistors.
Referring to FIG. 7, Q" 1 and Q" 2 denote NPN and PNP transistors, R" 1 , R" 2 resistors for stabilizing bias current, Z'" L a load including reactance, V' BB /2 bias power supply circuit, +V' c and +V" cc plus DC power supply circuits, -V' c and -V' cc minus DC power supply circuits, A"DC amplifier, Q' 3 , Q' 4 , Q' 5 , and Q' 6 transistors which have the same function as the diodes of the basic circuit shown in FIG. 2 with the addition of a current amplification function.
The operation of this circuit is the same as the basic circuit. This circuit is characterized in that transistors Q' 3 , Q' 4 are connected to transistor Q" 1 of the push-pull circuit by Darlington-connection, and transistors Q' 5 and Q' 6 are also connected to transistor Q" 2 of the push-pull circuit by Darlington-connection. With this circuit, it is possible to lessen the load on the DC amplifier circuit A", and also that on the input power supply.
As stated above, the present invention provides for high linearity even for reactance loads. Accordingly, this circuit is widely applicable to various kind of stabilized power supply circuit.
Particularly, if the circuit of FIG. 7 is used as a stabilizing circuit and using a reference power supply as an input e i , not only a good source ability for supplying a current but also a good sink ability for absorbing current will be obtained, thereby improving performance over that of a conventional amplifier.
Reference is finally made to the embodiment applicable to a high fidelity amplifier illustrated in FIG. 8, wherein Q'" 1 and Q'" 2 denote NPN and PNP transistors, R"" 1 , R"" 2 resistors for stabilizing bias current, Z"" L a load including reactance, V" BB /2 bias power supply circuit, +V" c and -V'" c plus DC power supply circuits, -V" c and -V" c minus DC power supply circuits, and Q" 3 , Q" 4 , Q" 5 and Q" 6 transistors which have the same function as the corresponding transistors Q' 3 , Q' 4 , Q' 5 and Q' 6 shown in FIG. 7.
In this example, two DC amplifiers are employed, whereby an amplifier A'" for adjusting the bias is included within a feedback loop for the amplifier A"" which sets the gain.
It is to be understood that modifications and variations of the embodiments of the invention disclosed herein may be resorted to without departing from the spirit of the invention and the scope of the appended claims. | An amplifier arrangement is provided which comprises first and second biasing power supply circuits, a push-pull amplifier comprising a pair of transistors, a DC amplifier having a non-inverting input terminal connected to a junction point at which one half of a predetermined potential fed from the first biasing power supply circuit is applied and an inverting input terminal connecting a feedback loop through which the output the amplifier is fedback, a second biasing power supply circuit having a junction point at which the output of the DC amplifier is applied, and means responsive to an output of the DC amplifier for applying either of the first and second predetermined potentials fed from the first and second biasing circuits in accordance with the amount of feedback from the output of the push-pull amplifier to produce an output signal showing a biasing current, whereby the output signal is applied to each base of the push-pull transistors so as to balance the half potential of the first biasing power supply circuit with the potential at the output of the push-pull amplifier. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present disclosure relates to vehicles, for example, rotorcraft with fluid cooled engines. More specifically, the present disclosure relates to redundant cooling systems for vehicles with fluid cooled engines or fluid cooled systems.
[0002] Fluid cooled systems, for example, internal combustion engines, require a cooling system that forces air across a heat exchanger to reject thermal energy from a working fluid that circulates through the engine. The cooling system must function during normal engine operation to prevent the engine from overheating that leads to engine failure. Such a cooling system is prone to failure of any one of the multiple components of the system, such as a fan, duct, heat exchanger or fluid distribution system including pumps and piping network Failure or malfunction of any of these components could lead to cooling system failure and, consequently, engine failure.
[0003] In some applications, aircraft have multiple engines for redundancy to meet safety and reliability requirements if a failure of one of the engines occurs. It is difficult to meet safety and reliability requirements if a failure of one of the above components of the cooling system can result in cooling system failure. To overcome this difficulty, the individual components, such as the fan, duct and heat exchanger are robustly designed to increase damage and flaw tolerance, with the penalty of additional weight, increased cost, larger component size, and loss of mission capability of the aircraft.
BRIEF DESCRIPTION OF THE INVENTION
[0004] A fluid cooled system includes a heat generating component. A first airflow pathway directs a first flow of air across a first heat exchanger. A second airflow pathway directs a second flow of air across a second heat exchanger. A working fluid is flowed from the heat generating component, through the first heat exchanger and through the second heat exchanger and returned to the heat generating component.
[0005] A rotorcraft includes an airframe and a rotor assembly operably connected to the airframe including a plurality of rotor blades operably connected to a rotor shaft. The rotorcraft further includes a fluid cooled engine system operably connected to the rotor assembly. The fluid cooled engine system includes an engine, a first airflow pathway to direct a first flow of air across a first heat exchanger, and a second airflow pathway to direct a second flow of air across a second heat exchanger. A working fluid is flowed from the engine, through the first heat exchanger and through the second heat exchanger and returned to the engine.
[0006] A method of operating a fluid cooled engine system includes urging a flow of a working fluid from a heat generating component and urging the flow of working fluid through a first heat exchanger. A first airflow is urged across the first heat exchanger via a first airflow pathway thereby transferring thermal energy between the flow of working fluid and the first airflow. The flow of working fluid is conveyed through a second heat exchanger and a second airflow is conveyed across the second heat exchanger via a second airflow pathway thereby transferring thermal energy between the flow of working fluid and the second airflow. The flow of working fluid is returned to the heat generating component.
[0007] These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
[0009] FIG. 1 is a schematic view of an embodiment of a rotary wing aircraft;
[0010] FIG. 2 is a schematic embodiment of an embodiment of a fluid cooled engine system;
[0011] FIG. 3 is a schematic of coolant flow in a fluid cooled engine system;
[0012] FIG. 4 is another schematic of coolant flow in a fluid cooled engine system;
[0013] FIG. 5 is a schematic of lubricant flow in a fluid cooled engine system;
[0014] FIG. 6 is another schematic of lubricant flow in a fluid cooled engine system; and
[0015] FIG. 7 is a schematic of fluid flow in a fluid cooled engine system.
[0016] The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0017] FIG. 1 is a schematic illustration of a rotary wing aircraft 10 having a main rotor assembly 12 . The aircraft 10 includes an airframe 14 having an extending tail 16 at which is mounted a tail rotor 18 . The main rotor assembly 12 is driven by two or more fluid cooled engines 20 connected to the main rotor assembly via a gearbox 22 .
[0018] Referring now to FIG. 2 , in some embodiments the aircraft 10 has two engines 20 , identified as 20 a and 20 b in the FIG. and is cooled via a cooling system 24 . It is to be appreciated that while the system 24 described herein is for cooling two engines 20 a and 20 b, the system 24 may be arranged to cool any number of engines 20 . Further, while the system 24 is described herein as applied to a rotary wing aircraft 10 , it may be applied to any use of a fluid cooled engine arrangement 20 . Also, while the system 24 described herein is utilized to cool engines, it is to be appreciated that the system 24 may be utilized to cool other heat generating components or machines.
[0019] A first engine 20 a is operably connected to a first fan 26 a which urges a flow of inlet air 28 into a first duct 30 a. A first coolant heat exchanger 32 a and first engine oil heat exchanger 34 a are arranged at the first duct 30 a upstream of a first duct outlet 36 a. Further, first engine 20 a is operably connected to a first coolant pump 38 a and a first oil pump 40 a.
[0020] Similarly, a second engine 20 b is operably connected to a second fan 26 b which urges a flow of inlet air 28 into a second duct 30 b. A second coolant heat exchanger 32 b and second engine oil heat exchanger 34 b are arranged at the second duct 30 b upstream of a second duct outlet 36 b. Further, second engine 20 b is operably connected to a second coolant pump 38 b and a second oil pump 40 b.
[0021] Flow of coolant and engine oil for engines 20 a and 20 b during normal operation of engines 20 a and 20 b and cooling system 24 is illustrated in FIGS. 3-6 . Referring to FIG. 3 , when the first engine 20 a is operating, the first fan 26 a, the first coolant pump 38 a and the first oil pump 40 a, driven by the first engine 20 a are also operating. The first fan 26 a urges inlet air 28 through the first duct 30 a and across the first coolant heat exchanger 32 a and the first engine oil heat exchanger 34 a. The first coolant pump 38 a pumps a first engine coolant flow 42 a from the first engine 20 a. The first coolant pump 38 a urges this first engine coolant flow 42 a through the first coolant heat exchanger 32 a, where thermal energy is transferred from the first engine coolant flow 42 a to the inlet air 28 flowing through the first duct 30 a. The first engine coolant flow 42 a is then urged to the second coolant heat exchanger 32 b and flowed therethrough to transfer thermal energy from the first engine coolant flow 42 a to inlet air 28 flowing through the second duct 30 b. After flowing through the second coolant heat exchanger 32 b, the first engine coolant flow 42 a is flowed into the first engine 20 a where thermal energy is transferred from the first engine 20 a to the first engine coolant flow 42 a to cool the first engine 20 a. Directing the first engine coolant flow 42 a through both the first coolant heat exchanger 32 a and the second coolant heat exchanger 32 b allows for effective cooling of the first engine 20 a even with failure of components such as the first coolant heat exchanger 32 a, the first fan 26 a or first duct 30 a.
[0022] Similarly, and referring now to FIG. 4 , a second engine coolant flow 42 b is pumped from the second engine 20 b by the second coolant pump 38 b. The second coolant pump 38 b urges the second engine coolant flow 42 b through the second coolant heat exchanger 32 b, where thermal energy is transferred from the second engine coolant flow 42 b to the inlet air 28 flowing through the second duct 30 b. The second engine coolant flow 42 b is then urged to the first coolant heat exchanger 32 a and flowed therethrough to transfer thermal energy from the second engine coolant flow 42 b to inlet air 28 flowing through the first duct 30 a. After flowing through the first coolant heat exchanger 32 a, the second engine coolant flow 42 b is flowed into the second engine 20 b where thermal energy is transferred from the second engine 20 b to the second engine coolant flow 42 b to cool the second engine 20 b. Directing the second engine coolant flow 42 b through both the second coolant heat exchanger 32 b and the first engine coolant heat exchanger 32 a allows for effective cooling of the second engine 20 b even with failure of components such as the second coolant heat exchanger 32 b, the second fan 26 b or second duct 30 b.
[0023] Referring to FIG. 5 , the first oil pump 40 a pumps a first engine oil flow 44 a from the first engine 20 a and through the first engine oil heat exchanger 34 a, where thermal energy is transferred between the first engine oil flow 44 a and the inlet flow 28 through the first duct 30 a. The first engine oil flow 44 a then proceeds through the second engine oil heat exchanger 34 b and thermal energy is transferred between the first engine oil flow 44 a and the inlet flow 28 through the second duct 30 b. The first engine oil flow 44 a is then flowed into the first engine 20 a to lubricate and transfer thermal energy from the first engine 20 a to the first engine oil flow 44 a to cool the first engine 20 a. Directing the first engine oil flow 44 a through both the first engine oil heat exchanger 34 a and the second engine oil heat exchanger 34 b allows for effective cooling of the first engine oil flow 44 a even with failure of components such as the first engine oil heat exchanger 34 a, the first fan 26 a or the first duct 30 a.
[0024] Referring to FIG. 6 , the second oil pump 40 b pumps a second engine oil flow 44 b from the second engine 20 b and through the second engine oil heat exchanger 34 b, where thermal energy is transferred between the second engine oil flow 44 b and the inlet flow 28 through the second duct 30 b. The second engine oil flow 44 b then proceeds through the first engine oil heat exchanger 34 a and thermal energy is transferred between the second engine oil flow 44 b and the inlet flow 28 through the first duct 30 a. The second engine oil flow 44 b is then flowed into the second engine 20 b to lubricate and transfer thermal energy from the second engine 20 b to the second engine oil flow 44 b to cool the second engine 20 b. Directing the second engine oil flow 44 b through both the second engine oil heat exchanger 34 b and the first engine oil heat exchanger 34 a allows for effective cooling of the second engine oil flow 44 b even with failure of components such as the second engine oil heat exchanger 34 b, the second fan 26 b or the second duct 30 b.
[0025] Referring now to FIG. 7 , the system 24 is still operable to serve a remaining engine in the case of failure of one engine. For example, as shown in FIG. 7 , in the case of a failure of the second engine 20 b, the system 24 would still serve the first engine 20 a with sufficient cooling capacity for continued normal operation. In the case of failure of the second engine 20 b, first engine coolant flow 42 a is not routed to second coolant heat exchanger 32 b, but is diverted back through first coolant heat exchanger 32 a for a second pass by operation of first coolant valve 46 a. Similarly, the first engine oil flow 44 a is not routed to second oil heat exchanger 34 b, but is diverted for a second pass through first oil heat exchanger 34 a by first oil valve 48 a. Second coolant valve 46 b and second oil valve 48 b (shown in FIG. 2 ) are provided to similarly divert the second engine coolant flow 42 b and the second engine oil flow 44 b in the case of a failure of the first engine 20 a. In some embodiments, sensors such as temperature sensors 50 and/or pressure sensors 52 are provided in the system 24 to assist in determining functionality of the system 24 . In some embodiments, the sensors are connected to a health monitor 54 or other controller that utilizes inputs from the sensors to determine if valves 46 a, 46 b, 48 a or 48 b should be used to divert the flows 42 a, 42 b, 44 a, 44 b from their respective normal paths.
[0026] While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims. | A fluid cooled system includes a first heat generating component. A first airflow pathway directs a first flow of air across a first heat exchanger. A second airflow pathway directs a second flow of air across a second heat exchanger. A first working fluid is flowed from the first heat generating component, through the first heat exchanger and through the second heat exchanger and returned to the first heat generating component. | 5 |
TECHNICAL FIELD
The present invention relates generally to thrust-vectoring actuation systems for rocket nozzles.
BACKGROUND OF THE INVENTION
It has been observed that thrust-vectoring actuation (TVA) systems for rockets are subjected to transient loads which accompany the startup and shutdown of rocket engines. These loads, which are transferred to the nozzle structure of the rocket via the TVA system, are unpredictable in terms of both amplitude and direction. However, the loads are sufficiently strong to raise concern about the possibility that the nozzle structure could yield under the influence of such loads, thereby putting the nozzle in an out-of-round condition.
The above-described loads are cyclic, and have frequencies which vary with the particular rocket in question. Available data indicate, for example, that the frequency can vary from about 4 Hz on the Centaur to about 12 Hz on the Titan IV. Accordingly, any system designed to compensate for the transient loads should have a response time which is sufficiently short in view of the applicable frequency.
This invention is directed to apparatus and methods for compensating for transient loads which tend to deform the nozzle or associated structure of a rocket, and which exceed normal operational loads. Objects and advantages of the invention will become apparent from the following description, which includes the appended claims and accompanying drawings.
SUMMARY OF THE INVENTION
The invention provides thrust-vectoring apparatus adapted to position a rocket nozzle that is operatively associated with a rocket engine, and comprises in combination: a bi-directional electric motor; an actuator shaft connected in driven relation to the motor and in driving relation to the nozzle; and means, connected to the shaft between the motor and the nozzle, for sensing a transient force associated with startup or shutdown of the engine.
In essence, the invention provides a method for preventing damage to the nozzle or associated structure, comprising the steps of sensing a transient force applied in the system between the nozzle and the motor, and when the transient force exceeds a predetermined threshold, activating the motor to drive the output shaft in a direction of compliance with respect to the transient force.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a conventional thrust-vectoring actuation system for controlling the position of a rocket nozzle.
FIG. 2 is a schematic diagram of a thrust-vectoring actuation system in accord with the invention.
FIG. 3 is an elevational view of a preferred embodiment of the invention.
FIG. 4 is a comparative graph illustrating the degree of transient load compensation attainable by use of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 of the drawings depicts one of two legs of a conventional TVA control system 10 for a rocket nozzle 12. The second leg is identical to the illustrated leg but controls the nozzle 12 along a plane (into and out from the drawing) which is ninety degrees apart from the illustrated leg.
The illustrated leg includes a bi-directional electric motor 14 under the control of a conventional analog controller 16. The motor 14 is connected through a gearbox 18 to an actuator shaft 20. The actuator shaft 20 is connected at its opposite end to the rocket nozzle 12. As inputs, the controller 16 receives position feedback signals (signified by arrow 22 and indicative of the actual position of the nozzle) for each leg from conventional position sensors (not shown), and a commanded position signal (signified by arrow 24)from an electronic control system. As outputs, the controller 16 communicates control signals along a line 26 to each motor 14, and the motors collectively respond to position the nozzle 12 as needed.
FIG. 2 illustrates a TVA control system 28 in accord with the invention. Otherwise conventional in structure, the system 28 of the present invention includes a force sensor 30, which may be provided in the form of a piezoelectric transducer or load cell, for example. The sensor 30 is connected in series with the actuator shaft 20 so that any force acting on and in the direction of the shaft will be sensed. Signals indicative of the force acting on the sensor 30 are communicated along a line 32 to the controller 16. The controller is adapted by conventional analog circuit elements--such as a deadband and appropriate amplification and filtering through which the signal on line 32 is processed before becoming an operative input to a summing junction which also receives an input indicative of the difference between the actual position on line 22 and the commanded position on line 24--to respond to the signals on line 32 only when the associated transient force exceeds a predetermined threshold in excess of the normal operational loads to which the shaft 20 is subjected. In that case, the controller communicates appropriate control signals to the motor 14, and the motor responds by driving the actuator shaft 20 in a direction of compliance with respect to the transient force. That is, if the force is compressive, the shaft is driven in a direction away from the nozzle 12, and if the force is tensile, the shaft is driven in a direction toward the nozzle.
FIG. 3 illustrates a preferred embodiment of the invention. Two bi-directional, brushless DC motors 14, 34 are connected in driving relation to a gearbox. 18, which in turn is connected in driving relation to an actuator shaft 36. A load cell 30 is rigidly connected by any suitable means to the actuator shaft 36. Leads (not shown) are connected to the cell 30 for electrical communication to the controller 16 (FIG. 2). The shaft 36 terminates with a rod end bearing 38 which in use is connected to the nozzle 12 (FIG. 2), while the motors 14, 34 are connected via a bracket 38 to the outer structure of a rocket.
FIG. 4 illustrates for a single pulse of force the extent of force compensation which can be achieved by the invention. Line 40 indicates the compensated load while line 42 indicates the uncompensated load on the actuator shaft.
Having described the preferred embodiment of the invention, it should be understood that the description is intended as illustrative, and is not intended to restrict the scope of the invention more than is indicated by the following claims: | A thrust-vectoring actuation system for a rocket nozzle is provided with a force sensor to enable detection of transient loads during startup and shutdown of a rocket engine. A motor responds to transient loads in excess of a predetermined threshold to drive the rocket nozzle in a direction of compliance with the transient loads. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. 119 to U.S. provisional application Ser. No. 60/612,919, filed Sep. 27, 2004, and entitled “METHOD AND COMPOSITION OF MATTER FOR TREATMENT OF WATER” the disclosure of which is hereby expressly incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to compositions and their use for the treatment of water. In one embodiment, the invention provides for a compositions and their use for the treatment of micro-organisms. This invention also provides compositions and their use to provide clean water in an environmentally-friendly manner. In another embodiment, the invention provides for compositions and their use in combination with common equipment for controlling the growth of micro-organisms, such as with an ozonator or UV-C lamp, in a water system such as in hot tub or pool. Additionally, the specification describes methods and compositions for controlling the growth of microorganisms in an aqueous system. Using the methods and compositions, one treats an aqueous system with an amount effective to control the growth of at least one microorganism. Accordingly, several advantages of the invention are providing improved water treatment, providing environmentally-friendly treatment, providing a more user-friendly treatment, and providing water that is better for human health.
BACKGROUND OF THE INVENTION
During the past few decades, water has become increasingly important to our modern lifestyles, especially, for relaxation and social gatherings in pools and hot tubs. More and more people build their own swimming pools inside of their homes or in their gardens and stay healthy by training their bodies in water regularly. Although water is available in many places across our planet, a reliable supply of clean water is less easy to obtain.
During the last decade, the hot tub was presented on the market as a healthy and relaxing bath, to reduce stress and relax in warm water of ca. 100° F. In these easy-to-install hot tubs, jets are installed to pump the water under high pressure within the bath, where the water power relaxes the muscles. Also, a hot tub bath has been shown to be healthy and decrease blood pressure. Taking a bath in a hot tub also became a social affair—a place where everyone can enjoy the warm water and relax after a hard day's work. This is the same with swimming pools, although swimming pools are used more for sport and conditioning. However, for a pool outside, good weather is required as well as a lot of space.
Especially in pools and hot tubs, where the water temperature is relatively high, are risky environments for rapid bacterial growth. That is why treatment of hot tub water is needed. Presently, vast quantities of chlorine are used in combination with specific bacteria-killing equipment, like ozonators or UV-C lighting. This is due to the fact that chlorine kills and removes sessile bacterial slime layers from the walls, whereas ozone or UV-C kills plankton-like bacteria. Chlorine only kills bacteria suspended in the water along with the top of the slime layers of surfaces, but not all microorganisms since many microorganisms grow within the slime layer.
However, the disadvantages of chlorine are:
1. It has an unpleasant odor 2. It irritates the skin, and dries it 3. Many people are allergic to chlorine and their eyes become irritated if they come into contact with the chemical 4. Chlorine not only eliminates water-born bacteria but also destroys benevolent dermatological bacteria 5. Breathing directly above the water surface is irritating to the lungs 6. After a bath, people have to take a shower to eliminate chlorine residue 7. Chlorine is not environmentally friendly 8. People generally have to wash and/or treat their skin after a bath.
When water is treated with chlorine, it is necessary to keep the pH value between 7.2 and 7.8, because higher or lower pH values reduces chlorine efficiency. However there is no reason why water should not have a pH of around 8.2 like seawater of which the medical qualities are well-known.
In order to maintain the pH in chlorine treatment between the optimal values, it is necessary to dose pH+ or pH− additives. In practice, this means that the owner of a hot tub or pool is always measuring pH values to keep the water in good condition. Technically it is possible to control this by means of a computer, however the instruments are expensive. Besides chlorine, there are other methods for treating water, such as bromide. In combination with chlorine, it forms bromine. In most countries the use of bromide is forbidden due to suspected carcinogenic action by the formed bromate.
Up to now there is no solution for water treatment that will not irritate the skin or cause skin damage. Furthermore, there is an urgent need for water treatment additives that are environmentally friendly, healthy, gentle on the skin, that do not irritate the airways or the eyes.
BRIEF SUMMARY OF THE INVENTION
The present invention relates to compositions and their use for removing coatings from a substrate. The present invention is directed to a composition comprising (a) one or more metasilicate; (b) one or more carbonate; (c) one or more glyconate; and (d) one or more sulfate. The composition may also contain (d) salts, e.g., sea salts and other additives.
In another embodiment, the composition is suitable for removing a biofilm from a surface and which does not produce or comprise a peroxide, a terpene or sodium hypochlorite.
In another embodiment, the one or more metasilicate is an alkali metal silicate selected from the group consisting of sodium or potassium metasilicate, sodium or potassium orthosilicate and mixtures thereof.
In another embodiment, the one or more carbonate is selected from the group consisting of sodium carbonate, sodium sesquicarbonate, sodium sulfate,—sodium bicarbonate and mixtures thereof.
In another embodiment, the glyconate is selected from the group consisting of ammonium glyconate, lithium glyconate, sodium glyconate, sodium starch glyconate, potassium glyconate, ammonium acid glyconate, sodium acid glyconate, lithium acid glyconate, potassium acid glyconate, ammonium D-glyconate, lithium D-glyconate, sodium D-glyconate, potassium D-glyconate, glyconic acid, glyconic D acid, glyconic L acid, ammonium L-glyconate, lithium L-glyconate, sodium L-glyconate, potassium L-glyconate, magnesium glyconate, magnesium acid glyconate, magnesium D-glyconate, magnesium L-glyconate, calcium glyconate, calcium acid glyconate, calcium D-glyconate, calcium L-glyconate and mixtures thereof.
In another embodiment, the one or more sulfate is selected from the group consisting of potassium aluminum sulfate, sulfuric acid, sodium sulfate, potassium sulfate, lithium sulfate, ammonium sulfate, magnesium sulfate, strontium sulfate, aluminum sulfate, and mixtures thereof.
In one embodiment, the composition is free of chlorinated solvents, environmentally safe and user-friendly.
Another embodiment of the invention is a method for removing biofilm from, and/or for preventing biofilm from forming on, a surface, comprising adding an effective amount of a composition of the present invention to a water system.
In one embodiment, the method further comprising passing an ozone-containing gas through the water.
In one embodiment, the method further comprising irradiating the supply of water with ultraviolet radiation.
In one embodiment, the present methods and compositions are used in hot tubs or pools. In another embodiment, the hot tubs or pools have an ozonator and/or UV-C lamp to facilitate elimination of the microorganisms, e.g., planktonic bacteria, and a fine mesh filter is installed to capture the residues.
Without wishing to be bound by theory, it is believed that the methods and compositions of the present invention aid biofilm to detach from walls and pipes and to coagulate.
Biofilms are matrix-enclosed accumulations of microorganisms such as bacteria (with their associated bacteriophages), fungi, protozoa and viruses that may be associated with these elements. While biofilms are rarely composed of a single cell type, there are common circumstances where a particular cellular type predominates. The non-cellular components are diverse and may include carbohydrates, both simple and complex, proteins, including polypeptides, lipids and lipid complexes of sugars and proteins (lipopolysaccharides and lipoproteins).
Planktonic bacteria, which are metabolically active, are adsorbed onto a surface which has copious amounts of nutrients available for the initial colonization process. Once adsorbed onto a surface, the initial colonizing cells undergo phenotypic changes that alter many of their functional activities and metabolic paths. For example, at the time of adhesion, Pseudomonas aeruginosa ( P. aeruginosa ) shows upregulated algC, algD, algU etc. genes which control the production of phosphomanomutase and other pathway enzymes that are involved in alginate synthesis which is the exopolysaccharide that serves as the polysaccharide backbone for P. aeruginosa 's biofilm. As a consequence of this phenotypic transformation, as many as 30 percent of the intracellular proteins are different between planktonic and sessile cells of the same species.
Planktonic cells adsorb onto a surface, experience phenotypic transformations and form colonies. Once the colonizing cells become established, they secrete exopolysaccharides that serves as the backbone for the growing biofilm. While the core or backbone of the biofilm is derived from the cells themselves, other components e.g., lipids, proteins etc, over time, become part of the biofilm. Thus a biofilm is heterogeneous in its total composition, homogenous with respect to its backbone and heterogeneous with respect it its depth, creating diffusion gradients for materials and molecules that attempt to penetrate the biofilm structure.
Biofilm-associated or sessile cells predominate over their planktonic counterparts. Not only are sessile cells physiologically different from planktonic members of the same species, there is phenotypic variation within the sessile subsets or colonies. This variation is related to the distance a particular member is from the surface onto which the biofilm is attached. The more deeply a cell is embedded within a biofilm i.e., the closer a cell is to the solid surface to which the biofilm is attached or the more shielded or protected a cell is by the bulk of the biofilm matrix, the more metabolically inactive the cells are. The consequences of this variation and gradient create a true collection of communities where there is a distribution of labor, creating an efficient system with diverse functional traits, that is, build an eco system for the microorganisms.
Biofilm structures cause the reduced response of bacteria to chlorine and the bactericidal consequences of antimicrobial and sanitizing agents. Chlorine resistance and persistent infections that are refractory to treatments are a major problem in bacteriological transmissions, resistance to eradication and ultimately pathogenesis. While the consequences of bacterial resistance and bacterial recalcitrance are the same, there are two different mechanisms that explain the two processes.
In one embodiment, the microorganisms contained in the biofilm may subsequently be killed by ozone or UV-C equipment after putting into solution.
In another specific embodiment, the present methods and compositions are used in cooling water systems. In another specific embodiment, the present methods and compositions are used in water reservoir systems.
One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objects and obtain the ends and advantages mentioned as well as those inherent therein. It should be understood, however, that the materials, compounds, coatings, methods, procedures, and techniques described herein are presently representative of preferred embodiments. These techniques are intended to be exemplary, are given by way of illustration only, and are not intended as limitations on the scope. Other objects, features, and advantages of the present invention will be readily apparent to one skilled in the art from the following detailed description; specific examples and claims; and various changes, substitutions, other uses and modifications that may be made to the invention disclosed herein without departing from the scope and spirit of the invention or as defined by the scope of the appended claims.
As used herein other than the claims, the terms “a,” “an,” “the,” and “the” means one or more. As used herein in the claim(s), when used in conjunction with the words “comprises” or “comprising,” the words “a,” “an,” “the,” or “the” may mean one or more than one. As used herein “another” may mean at least a second or more.
As would be known to one of ordinary skill in the art, many variations of nomenclature are commonly used to refer to a specific chemical composition. Accordingly, several common alternative names may be provided herein in quotations and parentheses/brackets, or other grammatical technique, adjacent to a chemical composition's preferred designation when referred to herein. Additionally, many chemical compositions referred to herein are further identified by a Chemical Abstracts Service registration number. As would be known to those of ordinary skill in the art, the Chemical Abstracts Service provides a unique numeric designation, denoted herein as “CAS No.,” for specific chemicals and some chemical mixtures, which unambiguously identifies a chemical composition's molecular structure.
In various embodiments described herein, exemplary values are specified as a range. It will be understood that herein the phrase “including all intermediate ranges and combinations thereof associated with a given range is all integers and sub-ranges comprised within a cited range. For example, citation of a range “0.03% to 0.07%, including all intermediate ranges and combinations thereof is specific values within the sited range, such as, for example, 0.03%, 0.04%, 0.05%, 0.06%, and 0.07%, as well as various combinations of such specific values, such as, for example, 0.03%, 0.06% and 0.07%, 0.04% and 0.06%, or 0.05% and 0.07%, as well as sub-ranges such as 0.03% to 0.05%, 0.04% to 0.07%, or 0.04% to 0.06%, etc.
Amounts of ingredients stated herein generally refer to the amount of the particular active ingredient (e.g., surfactant). Amounts stated for commercial products typically relate to the amount of the commercial product. The amount of active provided by the commercial product can be determined from the concentration of the commercial product and the fraction of the commercial product that is the active ingredient.
As used herein, the term “about” modifying the quantity of an ingredient in the compositions of the invention or employed in the methods of the invention refers to variation in the numerical quantity that can occur, for example, through typical measuring and liquid handling procedures used for making concentrates or use compositions in the real world; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of the ingredients employed to make the compositions or carry out the methods; and the like. Whether or not modified by the term “about”, it is intended that the claims include equivalents to the quantities.
Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods, devices, and materials are now described. All references, publications, patents, patent applications, and commercial materials mentioned herein are incorporated herein by reference for the purpose of describing and disclosing the cell lines, vectors, and methodologies which are reported in the publications which might be used in connection with the invention. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention.
The above summary of the present invention is not intended to describe each embodiment or every implementation of the present invention. Advantages and attainments, together with a more complete understanding of the invention, will become apparent and appreciated by referring to the following detailed description and claims.
Further aspects and advantages of this invention will be disclosed in the following examples, which should be regarded as illustrative and not limiting the scope of this application.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and, together with the general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention.
FIG. 1 provides a cross-sectional view of a hot tub.
FIG. 2 depicts a cross-sectional view of a pool.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to compositions and their use for the treatment of water. The present invention is directed to a composition comprising:
(a) one or more metasilicates (b) one or more carbonate; (c) one or more glyconate; and (d) one or more sulfate or aluminum salt.
In one embodiment, the composition further comprises (e) an inorganic salt.
In one specific embodiment, the present invention provides for a composition comprising:
(a) one or more metasilicates (b) one or more carbonate; (c) one or more glyconate; and (d) one or more sulfate or aluminum salt.
In another specific embodiment, the present invention provides for a composition additionally comprising:
(e) one or more inorganic salt.
In another specific embodiment, the present invention provides for a composition additionally comprising:
(f) one or more additional ingredients.
In one embodiment, the glyconate is selected from the group consisting of ammonium glyconate, lithium glyconate, sodium glyconate, sodium starch glyconate, potassium glyconate, ammonium acid glyconate, sodium acid glyconate, lithium acid glyconate, potassium acid glyconate, ammonium D-glyconate, lithium D-glyconate, sodium D-glyconate, potassium D-glyconate, glyconic acid, glyconic D acid, glyconic L acid, ammonium L-glyconate, lithium L-glyconate, sodium L-glyconate, potassium L-glyconate, magnesium glyconate, magnesium acid glyconate, magnesium D-glyconate, magnesium L-glyconate, calcium glyconate, calcium acid glyconate, calcium D-glyconate, calcium L-glyconate and mixtures thereof.
In one embodiment, the composition is in a dry or granulated state and can be combined with a suitable carrier, typically water, to form a solution. In another embodiment, the composition is in solution.
In one embodiment, the composition further comprises peroxygen compound. The peroxygen compound is preferably a perborate or a percarbonate and more preferably a percarbonate. The perborate or percarbonate preferably is complexed with a metal such as sodium, lithium, calcium, potassium or boron. The preferred percent by weight of the peroxygen compound in the composition, when in the dry or granular state, ranges from about 1% to about 40% and more preferably from about 2.5% to about 40%.
In another embodiment, the carbonate is a builder wherein the builder is at least one of the following compounds: a sodium carbonate (e.g., soda ash), sodium sesquicarbonate, sodium sulfate or sodium bicarbonate. In one embodiment, the carbonate is a hydrated carbonate such as trona. In one embodiment, the percent by weight of the builder in the cleaning composition, when in the dry or granular state, is from about 1% to about 75%. In another embodiment, the peroxygen compound, metasilicate and chelate are all salts having the same cation. In one embodiment, the cation is sodium or potassium.
A builder is also known as a sequestrant. A “sequestrant” is a molecule capable of coordinating (i.e., binding) the metal ions commonly found in natural water to prevent the metal ions from interfering with the action of the other ingredients of the composition. Some chelating/sequestering agents can also function as a threshold agent when included in an effective amount.
Optionally, the builders can be added, e.g., water soluble inorganic salt builders, preferably sodium salts, such as sodium polyphosphates, e.g. sodium tripolyphosphate and sodium pyrophosphate, sodium carbonate, sodium bicarbonate, sodium sesquicarbonate, sodium silicate, sodium disilicate, sodium metasilicate and sodium borate. In addition to the water soluble inorganic salts, water insoluble builders may also be useful, including the ion exchanging zeolites, such as Zeolite 4A. Organic builders may also be employed. Among suitable organic builders are polyacetal carboxylates, as described in U.S. Pat. No. 4,725,455, and water-soluble salts of lower hydroxycarboxylic acids, such as an alkali metal gluconate. Potassium or sodium gluconate are preferred.
Examples of aluminum salts suitable for use in the present invention include inorganic aluminum salts such as potassium aluminum sulfate, ammonium aluminum sulfate and aluminum chloride; and soluble aluminum carboxylates such as aluminum lactate, aluminum citrate and aluminum maleate.
Regarding these aluminum salts, in one embodiment, at least 90% by weight (hereinafter referred to as “%”) or more of their particles have diameters of 200 micrometers or less. In one embodiment, at least 90% or more of the particles which make up the composition have diameters of 200 micrometers or less, and, in one embodiment, the average particle diameter falls within a range of 20-150. Ideally, the average particle diameter should be between 20 and 100 micrometers.
These aluminum salts can be used singly or in combination. It is preferred that the aluminum salts be incorporated into the composition in the range of 0.5-20%, preferably from 1-10% and more preferably from 1-5%, based on the total amount of the composition. Preferably, the concentration of aluminum salts within the bath water should fall within 0.5-80 ppm, more preferably 1-40 ppm. If the concentration is less than 0.5 ppm, a refreshing feeling is not imparted to the bather. If the concentration exceeds 80 ppm, insoluble substances precipitate out of the bath water.
In another embodiment, the carbonate used in the present invention is one or more carbonates selected from the group consisting of sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, and sodium sesquicarbonate. In another embodiment, the carbonate used in the present invention is sodium carbonate and sodium bicarbonate. In another embodiment, the carbonates is incorporated in the composition in an amount of 10-98%, preferably 30-90%, based on the total amount of the composition.
In another embodiment, the carbonates in the water is 10 ppm or higher, preferably within the range of 10-400 ppm, and more preferably within 30-400 ppm.
Typical carbonates include sodium carbonate (Na2 CO3), potassium carbonate (K2 CO3) or other typical carbonate sources. Such carbonates can contain as an impurity some proportion of bicarbonate (HCO3.sup.-).
In another embodiment, the composition according to the present invention is prepared and used so that the pH of the final water falls between 7 and 9, and preferably within 7.0-8.5, when the composition is dissolved in the bath water. No limitation is imposed on the method of adjusting the pH of bath water. For example, the pH of bath water can be adjusted by changing the ratio of the above-mentioned components and the optional ingredients described hereinafter which are incorporated into the composition. The amounts of the above components are adjusted such that the pH of an aqueous 0.01% solution (4° C.) of the composition falls between 7 and 9.
In another embodiment, the composition, prior to final use, is prepared as a composition comprising:
Meta Silicate
about 2-10 kg
Carbonate
about 2-10 kg
Glyconate
about 1-5 kg
Aluminum Sulfate
about 1-5 kg per 300 liters of water.
In another embodiment, the composition, prior to final use, is prepared as a composition comprising:
Meta Silicate
about 4-6 kg
Carbonate
about 4-5 kg
Glyconate
about 1-2 kg
Potassium Al Sulfate
about 1-2 kg per 300 liters of water.
In another embodiment, the composition, prior to final use, is prepared as a composition comprising:
MetaSilicate
about 2-10 kg
Carbonate
about 2-10 kg
Glyconate
about 1-5 kg
Potassium Al Sulfate
about 1-5 kg
Inorganic Salt
about 1-5 kg per 300 liters of water.
In another embodiment, the composition, prior to final use, is prepared as a composition comprising:
Meta Silicate
about 4-6 kg
Carbonate
about 4-5 kg
Glyconate
about 1-2 kg
Potassium Al Sulfate
about 1-2 kg
Inorganic Salt
about 1-2 kg per 300 liters of water.
In another embodiment, the composition, prior to final use, is prepared as a composition comprising:
Meta Silicate
about 4.9 kg
Sodium Carbonate
about 4.5 kg
Sodium Glyconate
about 1.5 kg
Potassium Al Sulfate
about 1.5 kg per 300 liters of water.
In another embodiment, the composition, prior to final use, is prepared as a composition comprising:
Meta Silicate
about 4.9 kg
Sodium Carbonate
about 4.5 kg
Sodium Glyconate
about 1.5 kg
Inorganic salt
about 1.5 kg
Potassium Al Sulfate
about 1.5 kg per 300 liters of water.
In one specific embodiment, the present invention provides for a composition comprising:
(a) at least 1 mg/L of one or more metasilicates; (b) at least 1 mg/L of one or more carbonate (c) at least 0.5 mg/L of one or more glyconate; and (d) at least 0.2 mg/L of one or more sulfate selected from the group consisting of potassium aluminum sulfate, sulfuric acid, sodium sulfate, potassium sulfate, lithium sulfate, ammonium sulfate, magnesium sulfate, strontium sulfate, and aluminum sulfate; wherein the concentrations are the concentration in final solution in the water to be treated.
In another specific embodiment, the present invention provides for a composition additionally comprising:
(e) at least 0.6 mg/L of one or more salts.
In one specific embodiment, the present invention provides for a composition comprising:
(a) at least 1 mg/L of one or more metasilicates; (b) at least 2 mg/L of one or more carbonate (c) at least 0.8 mg/L of one or more glyconate; and (d) at least 0.8 mg/L of one or more sulfate selected from the group consisting of potassium aluminum sulfate, sulfuric acid, sodium sulfate, potassium sulfate, lithium sulfate, ammonium sulfate, magnesium sulfate, strontium sulfate, and aluminum sulfate; wherein the concentrations are the concentration in final solution in the water to be treated.
In another specific embodiment, the present invention provides for a composition additionally comprising:
(e) at least 1 mg/L of one or more salts.
In one specific embodiment, the present invention provides for a composition comprising:
(a) at least 3 mg/L of one or more alkali metal silicate selected from the group consisting of sodium or potassium metasilicate, orthosilicate or other water-soluble silicate; (b) at least 3 mg/L of one or more carbonate selected from the group consisting of sodium carbonate, sodium sesquicarbonate, sodium sulfate and sodium bicarbonate; (c) at least 0.9 mg/L of one or more glyconate; and (d) at least 0.8 mg/L of one or more sulfate selected from the group consisting of potassium aluminum sulfate, sulfuric acid, sodium sulfate, potassium sulfate, lithium sulfate, ammonium sulfate, magnesium sulfate, strontium sulfate, and aluminum sulfate; wherein the concentrations are the concentration in final solution in the water to be treated.
In another specific embodiment, the present invention provides for a composition additionally comprising:
(e) at least 0.6 mg/L of one or more salts.
In one specific embodiment, the present invention provides for a composition comprising:
(a) at least 1 mg/L of metasilicates; (b) at least 2 mg/L of sodium carbonate (c) at least 0.8 mg/L of sodium glyconate; and (d) at least 0.8 mg/L of potassium aluminum sulfate; wherein the concentrations are the concentration in final solution in the water to be treated.
In another specific embodiment, the present invention provides for a composition additionally comprising:
(e) at least 1 mg/L of one or more salts.
In one specific embodiment, the present invention provides for a composition comprising:
(a) from about 1 to about 100 mg/L of one or more metasilicates; (b) from about 1 to about 100 mg/L of one or more (c) from about 0.1 to about 60 mg/L of one or more glyconate; and (d) from about 0.1 to about 100 mg/L of one or more sulfate, wherein the concentrations are the concentration in final solution in the water to be treated.
In another specific embodiment, the present invention provides for a composition additionally comprising:
(e) from about 1 to about 100 mg/L of one or more salts.
In one specific embodiment, the present invention provides for a composition comprising:
(a) from about 1 to about 10 mg/L of one or more metasilicates; (b) from about 1 to about 10 mg/L of one or more carbonate (c) from about 0.01 to about 6 mg/L of one or more glyconate; and (d) from about 1 to about 10 mg/L of potassium aluminum sulfate, wherein the concentrations are the concentration in final concentration in the water to be treated.
In another specific embodiment, the present invention provides for a composition additionally comprising:
(e) from about 1 to about 10 mg/L of one or more salts.
Additional Embodiments
Substance
Range per liter water
Meta Silicate
0.001-1,000
mg
Sodium Carbonate
1.00-850
mg
Sodium Glyconate
0.00-540
mg
Salt inorganic
1.00-920
mg
Potassium Al Sulfate
1.50-830
mg
Fragrances
Another embodiment:
Meta Silicate
1.10-500
mg
Sodium Carbonate
1.70-720
mg
Sodium Glyconate
0.50-420
mg
Salt
0.60-300
mg
Potassium Al Sulfate
0.90-275
mg
Fragrances
Another embodiment:
Meta Silicate
1.20-7.00
mg
Sodium Carbonate
2.90-4.80
mg
Sodium Glyconate
0.80-3.50
mg
Salt inorganic
0.60-2.80
mg
Potassium Al Sulfate
0.20-1.90
mg
Fragrances
Another embodiment:
Meta Silicate
3.50-6.50
mg
Sodium Carbonate
3.20-4.00
mg
Sodium Glyconate
0.90-1.40
mg
Sea salt anorganic
1.00-1.35
mg
Potassium Al Sulfate
0.80-1.35
mg
Fragrances
1.00-1.10
mg
Against all expectations and documented evidence, the present inventors found that effective removal of biofilm may be achieved, using a solution comprising an amount of the composition described herein effective to treat a biofilm in a water system. In one embodiment, the water system is selected from the group consisting of hot tubs, spas, swimming pools, heat exchangers, cooling water systems, filtration systems, holding tanks, and small-scale reservoirs.
These compositions by themselves are sufficient to remove well-established biofilms in a period of time varying from within 1 hour to an indefinite time. In one embodiment, the treatment is between about 1 hour and 48 hours.
In accordance with the present invention, a method is provided for removing biofilm from, and/or for preventing biofilm from forming on, a surface of a vessel, conduit or other device that receives a supply of water. The method comprises adding to the supply of water a composition comprising: one or more metasilicate, one or more carbonate, one or more glyconate, and one or more sulfate.
In accordance with one embodiment of the present invention, a system is provided for removing biofilm from, and/or for preventing biofilm from forming on, a surface of a vessel, conduit or other device that receives a supply of water. In one embodiment, the system comprises a device a device for passing an ozone-containing gas through the water.
In accordance with another embodiment of the present invention, a system is provided for providing disinfected water to a conduit, and for removing biofilm from, and/or for preventing biofilm from forming on, an interior surface of a conduit. In another embodiment, system comprises an ultraviolet lamp disposed within an ultraviolet radiation permeable sleeve such that a channel is formed between an outer surface of the ultraviolet lamp and an inner surface of the sleeve. In another embodiment, an oxygen-containing gas is supplied to, and an ozone-containing gas is removed from, the channel. In another embodiment, the system includes a device for passing the ozone-containing gas to the conduit.
In accordance with yet another embodiment of the present invention, a system is provided for removing biofilm from, and/or for preventing biofilm from forming on, a surface of a vessel, conduit or other device that receives a supply of water. The system comprises a source of an ozone-containing gas, an ultraviolet irradiator for (a) receiving source water and producing disinfected water, or (b) receiving the ozone-containing gas and producing an ozone-diminished gas, a device for selectively routing either the disinfected water or the ozone-containing gas to the surface, and a device for selectively routing either the source water or the ozone-containing gas, downstream of the conduit, to the ultraviolet irradiator.
Ozone-containing gas removes biofilm much more efficiently than conventional disinfectants, such as chlorine. Also, because it is in a gaseous state, the ozone-containing gas is unlikely to leave a residual trace. Ozone digester further reduces the risk of harm from residual ozone. Generally, the ozone generator produces an ozone-containing gas, for example air+ozone, from an oxygen-containing gas, such as air. Alternatively, the oxygen-containing gas can be oxygen or oxygen-enriched air. The ozone-containing gas is produced by exposing oxygen-containing gas to a corona discharge or by irradiating oxygen-containing gas with ultra-violet radiation. The generation of ozone by shortwave ultraviolet radiation take place in the spectral region of 120 nm to 242 nm, with a peak output at 150 nm to 160 nm. The ultraviolet lamp is preferably a 185 nm wavelength lamp. A 185 nm wavelength lamp can produce approximately 0.5 grams per hour of ozone per 425 ma of lamp current, in dry air.
In one embodiment, the system includes an ultraviolet lamp is capable of producing radiation in a first wavelength range of about 120 nanometers to about 242 nanometers, preferably 185 nm, to induce the generation of a sufficient amount of ozone in the oxygen-containing gas. It is also capable of producing radiation in a second wavelength range of about 200 nanometers to about 300 nanometers, preferably 254 nm, in order to effectively kill most microorganisms such as airborne and surface bacteria, viruses, yeasts and molds. The ultraviolet lamp can be, for example, a dual wavelength low-pressure mercury lamp, or a medium pressure mercury lamp with a continuous spectrum. In one embodiment, the system includes an ozone digester. The ozone-containing gas is passed through ozone digester, which digests residual ozone.
In another embodiment of a system for removing biofilm from, and for preventing biofilm from forming on, a surface of a vessel, conduit or other device that receives a supply of water, and additionally for providing disinfected water to the surface. The system includes an ozone generator and a water disinfector.
In one embodiment, the system includes ozone generator, which supplies an ozone-containing gas. In one embodiment, the system includes a water disinfector, which supplies disinfected water.
In one embodiment, the system includes an ultraviolet lamp for irradiating untreated water from water source to produce disinfected water. The ultraviolet lamp generates ultraviolet radiation with a wavelength in the range of about 200 nanometers to about 300 nanometers. In another embodiment, the system includes ozone generator which includes an ultraviolet lamp for irradiating an oxygen-containing gas, such as pressurized air, to produce ozone-containing gas. The ultraviolet lamp generates ultraviolet radiation with a wavelength in the range of about 120 nanometers to about 242 nanometers.
Filters can be formed from at least one material selected from the group consisting of: activated carbon, activated carbon block, adsorption resins, ion exchange resins, zeolite, reduction catalysts, paper, polymers, clay, ceramics, metals, nylon, wood pulp, cellulose, cotton, fibers, and any other material capable of separating particulate, organics or inorganics from a feed stream. In one embodiment, the filter is in the form of one of the following: string wound filter, fiber composite molded filter, pleated filter, hollow fiber membrane, spiral wound membrane or sheet, plate and frame membrane and any other conventional form. When filter is used to remove organic materials, such as benzene, it is preferably formed of activated carbon or adsorption resin. To remove inorganic materials, such as heavy metals, or sulfites, the filter should be formed from ion exchange resin, zeolite or a reduction catalyst.
Another embodiment of a device suitable for use as a water disinfector is a PURA™ UV1-EPCB water purifier from Hydrotech, Inc. This product combines ultraviolet disinfection and carbon filtration in a compact system. In one embodiment, ultraviolet lamps, in consideration of its dual role, generates ultraviolet radiation with a first wavelength in the range of about 120 nanometers to about 242 nanometers, and a second wavelength in the range of about 200 nanometers to 300 nanometers.
Optionally, to prevent a release of any residual ozone from the system, the water can be directed to a filter (not shown) that destroys ozone by adsorption or reaction with wet granulated activated carbon, by contact with manganese dioxide, or by chemical reduction, such as by thiosulfate. In another embodiment, the system is controlled by a conventional computer or a programmable controller.
Optionally, the removal of biofilm from the system can be enhanced by periodically flushing it with a disinfectant, such as hypochlorite, chlorine dioxide (ClO 2 ) solution, hydrogen peroxide or other type of commercial disinfectant, such as BioVAC™ from Micrylium Labs. In one embodiment, the disinfectant flush is performed daily, weekly, monthly or every other month. The disinfectant solution may be introduced by means of a siphoned bottle (not shown) and a check valve (not shown), and the use of pressurized air as a driving force.
The ingredients may optionally be processed in an effective amount of an aqueous medium such as water to substantially blend and solubilize the ingredients and achieve a homogenous mixture, to aid in the hydration reaction if needed, to provide an effective level of viscosity for processing the mixture, and to provide the processed composition with the desired consistency. The water source is generally any source of water readily available. The water supply can also be bottled water, or water from any appropriate container or source, and the water can also be conditioned, such as by softening.
The highest concentrations confer a strength to the composition such as it is effective within one hour. The lowest concentrations confer a good performance within 18 hours.
Salts
In one embodiment, the composition utilizes a salt carrier. The salt carrier should not interfere with the compositions biological activity. When other materials are present, the salt carrier should not degrade those materials or interfere with their properties or biological activity. In other words, the salt carrier should be inert with respect to the other components.
In one embodiment, the composition can be formed into a tablet. A tablet according to the invention contains from about 40 to about 95 percent by weight of the salt carrier material. More preferably, the tablet contains about 50 to about 80 percent by weight of the matrix material, and most preferably from about 70 to about 80 percent.
The matrix material may be a single salt material or a mixture of two or more salts alone or in combination with other matrix materials. When the carrier matrix contains a mixture of salts, those salts are preferably present in equal amounts, e.g., a mixture of two salts in a 1:1 ratio. As discussed below, the ratio of salts may be adjusted to improve tablet stability, for example, by reducing the hygroscopicity of the carrier matrix.
The salt carrier is preferably a substantially water-soluble matrix. Preferably, the salt carrier is a water-soluble inorganic or organic salt or mixtures of such salts. For purposes of the present invention, water-soluble means having a solubility in water of about 0.2 grams per hundred grams of water at 2O.degree. C.
Examples of suitable salts for the carrier matrix include various alkali metal and/or alkaline earth metal sulfates, chlorides, borates, bromides, citrates, acetates, lactates, etc. Specific examples of suitable salts include, but are not limited to, sodium acetate, sodium bicarbonate, sodium borate, sodium bromide, sodium carbonate, sodium chloride, sodium citrate, sodium fluoride, sodium gluconate, sodium sulfate, calcium chloride, calcium lactate, calcium sulfate, potassium sulfate, tripotassium phosphate, potassium chloride, potassium bromide, potassium fluoride, magnesium chloride, magnesium sulfate and lithium chloride. The preferred salts are the inorganic salts, especially the Group 1 or 2 metal sulfates and chlorides. Particularly preferred salts, because of their low cost, are sodium sulfate, and sodium chloride. Sodium chloride may be substantially pure or in the form of rock salt, sea salt, or dendrite salt.
As mentioned above, the salt carrier may contain other carrier materials, preferably in amounts from 0 to about 10 percent by weight of the tablet. These materials are preferably solid and include other carrier materials known in the art. These materials may be solid organic acids such as benzoic, gluconic, or sorbic acid. Use of such materials may allow the salt carrier to have beneficial activity, including biological activity, in the aqueous system. For example, gluconic acid, or its salts, may be used in a carrier matrix. But when the tablet is added to an aqueous system, the gluconic acid may additionally function as a metal chelant to sequester iron and prevent iron oxide staining.
Anti-Deposition Agent
The compositions of the present invention can also include an anti-redeposition agent capable of facilitating sustained suspension of coatings in a solution and preventing the removed coatings from being redeposited onto the substrate being cleaned. Examples of suitable anti-redeposition agents include surfactants, metasilicates, zeolites, fatty acid amides, fluorocarbon surfactants, complex phosphate esters, styrene maleic anhydride copolymers, and cellulosic derivatives such as hydroxyethyl cellulose, hydroxypropyl cellulose, and the like. The present composition can include about 0.5-15 wt. %, e.g., about 1-5 wt. %, of an anti-redeposition agent. Preferably, the re-deposition inhibitor is a surfactant, a metasilicate, a zeolite or any combination thereof.
In certain embodiments, the anti-redeposition agent is present at about 0.1 to about 30 wt. %, about 0.2 to about 10 wt. %, or about 0.5 to about 2 wt. %. In an embodiment, the anti-redeposition agent is present at about 1 wt. %. The composition can include any of these ranges or amounts not modified by about.
Alternatively, alkali metal silicate, alkali metal nitrite, alkali metal carbonate, and/or alkali metal phosphate components may be added to the composition of this invention. The alkali metal silicate component functions as both an alkalinity contributor as well as an anti re-deposition aid, is preferably present in the amount of between about 0.1 to 15 wt. % and is constituted by a sodium or potassium metasilicate, orthosilicate or other water-soluble silicate.
Additional Components
In addition to the above-noted components of the compositions of the invention, various optional adjuvants can be incorporated. These include thickeners, diluents, brighteners, fragrances, dyes, opacifiers, chelants, pH adjustants and anti-rust additives.
Corrosion inhibitors may optionally be added to the composition. Corrosion inhibitors, also known as anti-corrosive or anti-rust agents, reduce the degradation of the metallic parts contacted by the detergent and are incorporated at a level of about 0.1% to about 15%, and preferably about 0.5% to about 5% by weight of the total composition. The use of such corrosion inhibitors is preferred when the detergent is in contact with a metal surface. Suitable corrosion inhibitors include alkyl and aryl carboxylic acids and carboxylate salts thereof; sulfonates; alkyl and aryl esters; primary, secondary, tertiary and aryl amines; phosphoric esters; epoxides; mercaptans; and diols. Also suitable are the C12-C20 fatty acids, or their salts, especially aluminium tristearate; the C12-C20 hydroxy fatty acids, or their salts; and neutralized tall oil fatty acids. Phosphonated octa-decane and other anti-oxidants such as betahydroxytoluene (BHT) may also be used.
Other non-limiting examples of representative corrosion inhibitors include ethoxylated butynediol, petroleum sulfonates, blends of propargyl alcohol and thiourea. If used, the amount of such corrosion inhibitors is typically up to about 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10% by weight of the total composition.
Other useful corrosion inhibitors include organic zinc complexes such as a zinc citrate, zinc hydroxy oxime complexes, and zinc copolymer complexes of acrylic acid ethacrylate; nitrogen and sulfur-containing aryl heterocycles; alkanolamines such as triethanolamine; amine-neutralized alkyl acid phosphates; dibasic acids-neutralized with amines, where the dibasic acids include, but are not limited to, adipic acid, succinic acid, sebacic acid, glutaric acid, malonic acid, suberic acid and examples of amines include, but are not limited to, methylamine, ethylamine, ethanolamine, diethanolamine, triethanolamine and N,N-dimethylcyclohexylamine, and mixtures thereof. Each of the above-mentioned anti-corrosives can be used individually or in combination thereof, or in combination with other types of additives.
Optionally, the compositions of the invention may also contain a thickener which functions not only as a viscosifying thickener but also as an emulsion stabilizing agent stabilizing the emulsions of the invention against separation at elevated temperatures. Illustrative thickeners which may be used in the practice of the invention include acrylic acid/alkyl methacrylate copolymers (Acrysol ICS-I or Acusol 820), carboxy acrylic polymers (Carbopol 940), guar gums, xanthan gums, polyacrylic acid crosslinked with polyalkenyl polyvinyl alcohol, ammonium alginate and sodium alginate. Other thickeners known to the art may also be used. When incorporated into the composition of the invention, preferably from approximately 0.1 to 2 wt. % of the thickener is used. The preferred thickeners include acrylic acid/alkyl methacrylate copolymers and carboxy acrylic polymers. Where the thickener component is one which contains free acidic groups (e.g. Accusol 820 or Carbopol 940), a neutralizing base such as mono-, di- or triethanolamine or other neutralizing base is incorporated to ionize or neutralize the free acid groups and produce the full thickening effect of the thickener component.
The use of one or more pH-adjusting agents, including minor amounts of mineral acids, basic compositions, and organic acids may be used. An exemplary composition includes citric acid, such as is available in an anhydrous salt form of an alkali metal citric acid. The addition of an effective amount of such a pH-adjusting agent is useful in establishing a targeted pH range for compositions according to the invention. The addition of an effective amount of a pH buffering composition so as to maintain the pH of the inventive compositions may also be added. While the composition of the invention generally does not require a pH buffering composition, the use of such a pH buffering composition may provide the benefit of hard water ion sequestration. Examples of such useful pH buffer compounds and/or pH buffering systems or compositions are alkali metal phosphates, polyphosphates, pyrophosphates, triphosphates, tetraphosphates, silicates, metasilicates, polysilicates, carbonates, hydroxides, and mixtures of the same. Certain salts, such as the alkaline earth phosphates, carbonates, hydroxides, can also function as buffers. It may also be suitable to use as buffers such materials as aluminosilicates (zeolites), borates, aluminates and certain organic materials such as gluconates, succinates, maleates, citrates, and their alkali metal salts. Such buffers keep the pH ranges of the compositions of the present invention within acceptable limits. Others, not particularly elucidated here may also be used. Preferably, citric acid, such as is available in an anhydrous salt form of an alkali metal citric acid is added as it is readily commercially available, and effective. The addition of such a buffering agent is desirable in certain cases wherein long term, i.e., prolonged storage, is to be anticipated for a composition, as well as insuring the safe handling of the aqueous composition.
In even more preferred embodiments, the composition further comprises biofilm dislodging enhancer agents such as chaotropic agents or calcium chelators.
A calcium chelator such as EDTA, preferably in a salt form, in a concentration of at least about 0.25% or any calcium chelator having a chelating potency substantially equivalent thereto may be added.
Chelators: Tetrasodium EDTA (0.25%-1%) has been tried with a certain degree of success against biofilms. Any chelator in a concentration equipotent to the above concentrations of EDTA is within the scope of this invention. It is worthwhile noting that HEEDTA has been used in the acid form (0.3%) and was good when another salt forming acid: acetic acid, was at a concentration of 0.1% to 1% and when the pH was brought from 2.42 to 5.0. So, chelator salts can be used or chelator acid precursors can be used in salt forming conditions. It is recalled that the chelator is an optional component; it is used to increase the cleaning strength of the solution. Its function is mainly to capture divalent ions such as Ca.sup.2+ which are involved in EPS integrity.
A chaotropic agent such as SDS in a concentration of at least about 0.1% or any chaotropic agent having a chaotropic potency substantially equivalent thereto may also be added.
In more preferred embodiments, the compositions comprise at least about 0.1% SDS, at least about 0.1% acid, at least about 0.25% EDTA, the acid being selected from the group consisting of 2-ketoglutaric, acetic, iminodiacetic, mucic, glycolic, fumaric, aspartic, phosphoric, pyruvic, chloroacetic acids and alanine.
In a mostly preferred embodiment, the compositions comprise at least about 0.1% but less than 1% SDS, about 0.1%-2% acid, and at least about 0.25% but less than 1% EDTA, the acid being mandelic acid or any other of 2-ketoglutaric, acetic, iminodiacetic, mucic, glycolic, fumaric, aspartic, phosphoric, pyruvic, chloroacetic acids and alanine.
Chaotropic Agents: SDS has a dual action as a detergent and a chaotropic agent. Since a plurality of non-chaotropic detergents may substitute for SDS, the chaotropic activity is not considered essential to the claimed compositions. However, since SDS was the preferred detergent, it is contemplated that a chaotropic agent may be useful, as an optional component, in increasing the cleaning strength of the solution. Any chaotropic agent having the potency of in a concentration of at least about 0.1% SDS is within the scope of this invention.
Bactericides: When it is desirable to complete the cleaning solution with a bactericidal activity, especially in the medical field, a bactericide can be added in an effective concentration. It is recalled that bactericides alone are less effective against biofilms than against planktonic microorganisms. However, when bactericides are combined to a detergent/salt solution, or contacted with surfaces thereafter, they are capable of killing microorganisms which are retrieved as planktonic organisms and no longer organized as a biofilm, due to the detergent/acid/salt effect. Povidone-iodine 10%, mandelic acid 1%, sodium benzoate/salicylate 2%/0.2%, hydrogen peroxide 5%, sodium hypochlorite 0.5%, phenol 0.1% and CPC 0.1%-0.5% have all been tried with success, which indicates that any bactericide may be added in the cleaning solution in so far as the selected bactericide has a killing activity against the populations of microorganisms to eliminate.
Bactericidal Agents
Enzymatic enzymes include any member from the class of oxido-reductases, EC 1 that generate active oxygen; Monosasccharide oxidases, Peroxidases, Lactoperoxidases, Salivary peroxidases, Myeloperoxidases, Phenol oxidase, Cytochrome oxidase, Dioxygenases, Monooxygenases. The enzymes also include bacterial cell lytic enzymes, e.g., Lysozyme, Lactoferrin
Other agents include antimicrobials e.g., chlorhexidine, amine fluoride compounds, fluoride ions, hypochlorite, quaterinary ammonium compounds e.g. cetylpyridinium chloride, hydrogen peroxide, monochloramine, providone iodine, any recognized sanitizing agent or oxidative agent and biocides.
Also included are antibiotics, including, but not limited to the following classes and members within a class:
Aminoglycosides: Gentamicin, Tobramycin, Netilmicin, Amikacin, Kanamycin, Streptomycin, Neomycin Quinolones/Fluoroquinolones: Nalidixic Acid, Cinoxacin, Norfloxacin, Ciprofloxacin, Perfloxacin, Ofloxacin, Enoxacin, Fleroxacin, Levofloxacin Antipseudomonal: Carbenicillin, Carbenicillin Indanyl, Ticarcillin, Azlocillin, Mezlocillin, Piperacillin Cephalosporins: Cephalothin, Cephaprin, Cephalexin, Cephradine, Cefadroxil, Cefazolin, Cefamandole, Cefoxitin, Cefaclor, Cefuroxime, Cefotetan, Ceforanide, Cefuroxine Axetil, Cefonicid, Cefotaxime, Moxalactam, Ceftizoxime, Ceftriaxone, Cefoperazone, Cftazidime, Cephaloridine, Cefsulodin Other beta-Lactam Antibiotics: Imipenem, Aztreonam beta-Lactamase Inhibitors: Clavulanic Acid, Augmentin, Sulbactam Sulfonamides: Sulfanilamide, Sulfamethoxazole, Sulfacetamide, Sulfadiazine, Sulfisoxazole, Sulfacytine, Sulfadoxine, Mafenide, p-Aminobenzoic Acid, Trimethoprim-Sulfamethoxazole Urinary Tract Antiseptics: Methenamine, Nitrofurantoin, Phenazopyridine and other napthpyridines Penicillins: Penicillin G and Penicillin V Penicillinase Resistant Methicillin, Nafcillin, Oxacillin, Cloxacillin, Dicloxacillin Penicillins for Gram-Negative/Amino Penicillins: Ampicillin (Polymycin), Amoxicillin, Cyclacillin, Bacampicillin Tetracyclines: Tetracycline, Chlortetracycline, Demeclocycline, Methacycline, Doxycycline, Minocycline Other Antibiotics Chloramphenicol (Chlormycetin), Erythromycin, Lincomycin, Clindamycin, Spectinomycin, Polymyxin B (Colistin), Vancomycin, Bacitracin Tuberculosis Drugs Isoniazid, Rifampin, Ethambutol, Pyrazinamide, Ethinoamide, Aminosalicylic Acid, Cycloserine Anti-Fungal Agents: Amphotericin B, Cyclosporine, Flucytosine Imidazoles and Triazoles: Ketoconazole, Miconazaole, Itraconazole, Fluconazole, Griseofulvin Topical Anti Fungal Agents: Clotrimazole, Econazole, Miconazole, Terconazole, Butoconazole, Oxiconazole, Sulconazole, Ciclopirox Olamine, Haloprogin, Tolnaftate, Naftifine, Polyene, Amphotericin B, Natamycin
The term “treat”, “treating”, or “treatment” as used herein refers to regulating a population of a deleterious microorganism that may form a biofilm. The population may be regulated by the compositions and methods of the present invention so that the microorganism is killed, thereby reducing the viable populations such as by bacteriocidal or fungicidal or the like. The methods and compositions of the present invention may maintain and not allow a population of a deleterious organism to increase or may prevent an invasion by a deleterious microorganism.
The term “pH buffering agent” as used herein refers to any organic or inorganic compound or combination of compounds that will maintain the pH of a solution to within about 0.5 pH units of a selected pH value. A “pH buffering agent” may be selected from, but is not limited to, Tris (hydroxymethyl) aminomethane (tromethaprim; TRIZMA base), or salts thereof, phosphates, amino acids, polypeptides or any other pH buffering agent or combination thereof.
As used herein, the term “antioxidant” is intended to mean an agent that inhibits oxidation and thus is used to prevent the deterioration of preparations by oxidation. Such compounds include, by way of example and without limitation, ascorbyl palmitate, butylated hydroxyanisole, butylated hydroxytoluene, monothioglycerol, sodium ascorbate, sodium formaldehyde sulfoxylate and sodium metabisulfite and others known to those of ordinary skill in the art. Other suitable antioxidants include, for example, BHT, BHA, sodium bisulfite, vitamin E and its derivatives, propyl gallate or a sulfite derivative.
Buffering agents are used to control the pH of an aqueous solution in which the film is immersed so as to maintain the pH of the core in the approximately neutral or alkaline range. A buffering agent is used to resist change in pH upon dilution or addition of acid or alkali. Such compounds include, by way of example and without limitation, potassium metaphosphate, potassium phosphate, monobasic sodium acetate and sodium citrate anhydrous and dihydrate, salts of inorganic or organic acids, salts of inorganic or organic bases, and others known to those of ordinary skill in the art.
Preservatives include compounds used to prevent the growth of microorganisms. Suitable preservatives include, by way of example and without limitation, benzalkonium chloride, benzethonium chloride, benzyl alcohol, cetylpyridinium chloride, chlorobutanol, phenol, phenylethyl alcohol, phenylmercuric nitrate and thimerosal and others known to those of ordinary skill in the art.
As used herein, the term “diluent” or “filler” is intended to mean inert substances used as fillers to create the desired bulk, flow properties, and compression characteristics in the preparation of the cores. Such compounds include, by way of example and without limitation, dibasic calcium phosphate, kaolin, lactose, sucrose, mannitol, microcrystalline cellulose, powdered cellulose, precipitated calcium carbonate, sorbitol, and starch and other materials known to one of ordinary skill in the art.
By the term “effective amount”, it is understood that it is the amount or quantity of composition, which is sufficient to elicit the required or desired response, or in other words, the amount that is sufficient to elicit an appreciable biological response when administered to a water system.
Buffering agents help to maintain the pH in the range which approximates physiological conditions. They are preferably present at concentration ranging from about 2 mM to about 50 mM. Suitable buffering agents for use with the present invention include both organic and inorganic acids and salts thereof such as citrate buffers (e.g., monosodium citrate-disodium citrate mixture, citric acid-trisodium citrate mixture, citric acid-monosodium citrate mixture, etc.), succinate buffers (e.g., succinic acid-monosodium succinate mixture, succinic acid-sodium hydroxide mixture, succinic acid-disodium succinate mixture, etc.), tartrate buffers (e.g., tartaric acid-sodium tartrate mixture, tartaric acid-potassium tartrate mixture, tartaric acid-sodium hydroxide mixture, etc.), fumarate buffers (e.g., fumaric acid-monosodium fumarate mixture, etc.), fumarate buffers (e.g., fumaric acid-monosodium fumarate mixture, fumaric acid-disodium fumarate mixture, monosodium fumarate-disodium fumarate mixture, etc.), gluconate buffers (e.g., gluconic acid-sodium glyconate mixture, gluconic acid-sodium hydroxide mixture, gluconic acid-potassium glyuconate mixture, etc.), oxalate buffer (e.g., oxalic acid-sodium oxalate mixture, oxalic acid-sodium hydroxide mixture, oxalic acid-potassium oxalate mixture, etc.), lactate buffers (e.g., lactic acid-sodium lactate mixture, lactic acid-sodium hydroxide mixture, lactic acid-potassium lactate mixture, etc.) and acetate buffers (e.g., acetic acid-sodium acetate mixture, acetic acid-sodium hydroxide mixture, etc.). Additionally, there may be mentioned phosphate buffers, histidine buffers and trimethylamine salts such as Tris.
Preservatives are added to retard microbial growth, and are added in amounts ranging from 0.2%-1% (w/v). Suitable preservatives for use with the present invention include phenol, benzyl alcohol, meta-cresol, methyl paraben, propyl paraben, octadecyldimethylbenzyl ammonium chloride, benzalconium halides (e.g., chloride, bromide, iodide), hexamethonium chloride, alkyl parabens such as methyl or propyl paraben, catechol, resorcinol, cyclohexanol, and 3-pentanol.
The formulation herein may also contain more than one active compound as necessary for the particular indication being treated, preferably those with complementary activities that do not adversely affect each other. The active ingredients may also be entrapped in microcapsule prepared, for example, by coascervation techniques or by interfacial polymerization, for example, hydroxymethylcellulose or gelatin-microcapsule and poly-(methylmethacylate) microcapsule. Sustained-release preparations may be prepared. Suitable examples of sustained-release preparations include semi-permeable matrices of solid hydrophobic polymers, which matrices are in the form of shaped articles, e.g., films, or microcapsules.
For some uses, it might be desirable to add an anti-foamer. Also, a dye might be added to the compositions of this invention for easy monitoring of the extent of rinsing. In another embodiment, refreshing 30% of the water periodically will remove foam.
Various dyes, odorants including perfumes, and other aesthetic enhancing agents may also be included in the composition. Dyes may be included to alter the appearance of the composition, as for example, Direct Blue 86 (Miles), Fastusol Blue (Mobay Chemical Corp.), Acid Orange 7 (American Cyanamid), Basic Violet 10 (Sandoz), Acid Yellow 23 (GAF), Acid Yellow 17 (Sigma Chemical), Sap Green (Keyston Analine and Chemical), Metanil Yellow (Keystone Analine and Chemical), Acid Blue 9 (Hilton Davis), Sandolan Blue/Acid Blue 182 (Sandoz), Hisol Fast Red (Capitol Color and Chemical), Fluorescein (Capitol Color and Chemical), Acid Green 25 (Ciba-Geigy), and the like. Fragrances or perfumes that may be included in the compositions include, for example, terpenoids such as citronellol, aldehydes such as amyl cinnamaldehyde, a jasmine such as CIS-jasmine or jasmal, vanillin, and the like.
In another embodiment, bleaching agents for use in the compositions for lightening or whitening a substrate can be included, include bleaching compounds capable of liberating an active halogen species, such as Cl2, Br2, -OCl.sup.- and/or -OBr.sup.-, under conditions typically encountered during the cleansing process. Suitable bleaching agents for use in the present compositions include, for example, chlorine-containing compounds such as a chlorine, a hypochlorite, chloramine. Preferred halogen-releasing compounds include the alkali metal dichloroisocyanurates, chlorinated trisodium phosphate, the alkali metal hypochlorites, monochloramine and dichloramine, and the like. Encapsulated chlorine sources may also be used to enhance the stability of the chlorine source in the composition (see, for example, U.S. Pat. Nos. 4,618,914, and 4,830,773, the disclosure of which is incorporated by reference herein). A bleaching agent may also be a peroxygen or active oxygen source such as hydrogen peroxide, perborates, sodium carbonate peroxyhydrate, phosphate peroxyhydrates, potassium permonosulfate, and sodium perborate mono and tetrahydrate, with and without activators such as tetraacetylethylene diamine, and the like. A composition may include a minor but effective amount of a bleaching agent, preferably about 0.1-10 wt-%, preferably about 1-6 wt-%.
In one embodiment, the compositions of the present invention are used in combination with an ozonator and/or UV-C lamp. In another embodiment, the compositions of the present invention force biofilms to release from walls and pipes and coagulates the resulting residues.
In another embodiment, the compositions of the present invention are used in methods of treating water. Begin with a clean hot tub or pool filled with clear, fresh water, or clear water previously treated with chlorine. Pour out the appropriate dosage of the product on the water surface. Jets in the hot tub, or pumps in the swimming pool, should be activated to ensure that the product mixes with the water.
In one embodiment, the composition is added to the water to be treated on a continuous manner. In another embodiment, it is added daily. In another embodiment, it is added weekly.
In another embodiment, water includes a filter. In another embodiment, the filter is cleaned once or twice per week with the filter cleaner delivered with the compositions of the present invention.
In another embodiment, the compositions are used in a pool. In another embodiment, the pool filter is backwashed. In another embodiment, the pool filter is backwashed once or twice a week. In another embodiment, the filter is a zeolite filter. Zeolite filter is preferred In another embodiment, the pool filter is a sand filter.
CONTENTS
ADD
CONTENTS
ADD
IN LITRES
WEEKLY IN
IN LITRES
WEEKLY IN
OF HOTTUB
MILILITER
OF POOL
LITRES
800-900
225
2,500
0.1
900-1,000
250
5,000
0.2
1,000-1,100
275
10,000
0.4
1,100-1,200
300
20,000
0.5
1,200-1,300
325
30,000
1.2
1,300-1,400
350
40,000
1.6
1,400-1,500
375
50,000
2.0
1,500-1,600
400
60,000
2.4
1,600-1,700
425
70,000
2.8
1,700-1,800
450
80,000
3.2
1,800-1,900
475
90,000
3.6
1,900-2,000
500
100,000
4.0
The solution concentrates of the invention further include water sufficient to provide the remaining weight of the composition. Deionized or distilled water is preferably employed.
The present water additive composition may contain the following optional ingredients if desired:
(a) inorganic acids such as boric acid, metasilicic acid and silicic anhydride; (b) inorganic salts such as sodium chloride, sodium sulfate, potassium nitrate, sodium nitrate, calcium nitrate, sodium polyphosphate, ammonium chloride, ferrous sulfate, sodium phosphate and sodium thiosulfate; (c) crude drugs such as atractylodes rhizoma, atractylodes macrocephala, Japanese valerian, nepeta japonica, magnolia bark, cnidium rhizoma, bitter orange peel, ligusticum, powdered ginger, ginseng, cinnamon, paeoniae radix, peppermint leaves, Scutellariae radix, gardenias fructus, tackahoe, angelicae tuhou radix, calamus root, artemisias argyi folium, schisandra repanda, angelica dahurica root, houttuynia cordata, bomeol, suffron crocus, phellodendron extract, citrus unshiu peel, fennel, citri pericarpium pulveratum, camomile, melissa, rosemary, horse chestnut, milfoil and mountain amica. (d) oils and fats such as isopropylpalmitate, isopropylmyristate, cholesteryl isostearate, squalane, tri(capryl-capric acid) glycerol, rice-bran oil, rice-bran extract, 1-isostearoyl-3-myristoyl-glycerol, olive oil, jojoba oil, soybean oil, liquid paraffin and white Vaseline; (e) alcohols such as ethanol, stearyl alcohol, isopropyl alcohol, cetyl alcohol and hexadecyl alcohol; (f) polyols such as glycerol, propylene glycol and sorbitol; (g) surfactants such as alkyl sulfate, polyoxyethylene alkyl ether sulfate, lauric acid diethanolamide, polyoxyethylene alkyl ether, polyethylene glycol monostearate; and (h) other ingredients such as titanium oxide, zinc oxide, talc, sulfur, ore sand, neutral terra abla, sodium salicylate, yolk powder, parched rice-bran, mica powder and powdered skim milk.
The water additive compositions of this invention may further include preservatives, moisturizers, metal sequestering and chelating agents, perfumes and other ingredients. The compositions of the present invention are prepared by conventional methods to form powders, granules, tablets and the like.
The preferred embodiments are exemplified by the following nonlimiting examples.
EXAMPLES
Example 1
FIG. 1 . is a cross-sectional view of a hot tub ( 100 ) to be treated. Circulation of water ( 10 ) is illustrated, which begins in the hot tub water reservoir ( 15 ) itself where the surface water ( 10 ) flows through the filter ( 40 ). After the water ( 10 ) has been filtered, the water ( 10 ) passes through the heater ( 60 ) and from the heater ( 60 ) through the pump ( 30 ). After that, the water ( 10 ) flows back into the hot tub water reservoir ( 15 ). The flow can be controlled by the power of the pump ( 30 ) and there is a possibility to inject extra air into the water though the air control unit ( 70 ). An ozonator ( 50 ) is installed separately, and injects O 3 into the water ( 10 ) to kill the bacteria. The bubbles from the ozonator ( 50 ) enter the water ( 10 ) through the “ozonator exit” opening. The ozonator ( 50 ) is controlled according to the pollution level: from three times two hours in a twenty-four hour period, to six times two hours in a twenty-four period. In one instance, the ozonator ( 50 ) runs six times for two hours each, in a twenty-four hour period.
Example 2
FIG. 2 . is a cross-sectional view of a pool ( 200 ) to be treated. The water treatment composition ( 20 ) of the present invention is poured onto the water surface. Circulation of water ( 110 ) is illustrated, which begins in the pool ( 200 ) itself where the surface water ( 110 ) enters into the skimmer ( 45 ). From the skimmer ( 45 ) the water ( 110 ) goes through the filter ( 140 ) and from there the water ( 110 ) passes near the UV-C lamp and/or ozonator ( 150 ) for disinfection. After this the water ( 110 ) returns to the pool ( 200 ) through jets. Generally, at least once a week the filter ( 140 ) is backwashed. The wastewater flows into the sewer system. In this system, the wastewater is not polluted with chemicals that can damage the environment.
The description fully satisfies the objects, aspects and advantages set forth. While the invention has been set forth in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in the light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations which fall within the spirit and scope of the following claims. | The present invention relates to compositions and their use for the treatment of water. In one embodiment, the invention provides for a compositions and their use for the treatment of microorganisms. This invention also provides compositions and their use to provide clean water in an environmentally-friendly manner. In another embodiment, the invention provides for compositions and their use in combination with common equipment for controlling the growth of micro-organisms, such as with an ozonator or UV-C lamp, in a water system such as in hot tub or pool. Additionally, the specification describes methods and compositions for controlling the growth of microorganisms in an aqueous system. Using the methods and compositions, one treats an aqueous system with an amount effective to control the growth of at least one microorganism. Accordingly, several advantages of the invention are providing improved water treatment, providing environmentally-friendly treatment, providing a more user-friendly treatment, and providing water that is better for human health. | 2 |
[0001] This is a Continuation of application Ser. No. 10/653,288 filed Sep. 3, 2003, which in turn is a Continuation of Parent application Ser. No. 09/701,556, filed Mar. 16, 2001 as a National Stage Entry of PCT/FR99/01278, filed Jun. 1, 1999.
[0002] The present invention relates to the technical field of paper production and the polymers used in this field.
[0003] The invention relates to a process for producing a paper or paperboard with improved retention and other properties.
[0004] During the production of paper, paperboard, or the like, it is well known to introduce into the pulp retention aids whose function is to retain a maximum of fines and fillers in the sheet. The beneficial effects that result from the utilization of a retention aid are essentially:
increased production and reduction of production costs: energy savings, more reliable operation of the machine, higher yield in terms of fibers, fines, fillers and anionic finishing products, lower acidity in the circuit linked to a decrease in the use of aluminum sulfate, and hence a reduction in corrosion problems; an improvement in quality: better formation and better look-through, an improvement in the moisture content, the opacity, the gloss, and the absorptive capacity of the sheet, and a reduction in the porosity of the paper.
[0007] Long ago, it was proposed that bentonite be added to the pulp, possibly together with other mineral products such as aluminum sulfates or even synthetic polymers, notably polyethylene imine (see for example the documents DE-A-2 262 906 and U.S. Pat. No. 2,368,635).
[0008] In the document U.S. Pat. No. 3,052,595, it was proposed to associate the bentonite with a polyacrylamide of an essentially linear nature. This process met with competition from systems that were easier to use yet performed just as well. Moreover, even with the current linear polyacrylamides, the retention capacity is still insufficient.
[0009] In the document EP-A-0 017 353, it was proposed, for the retention of low-filler pulps (less than 5% fillers), to associate the bentonite with a nonionic to slightly anionic linear copolyacrylamide. This process has not been very widely used, since these polymers perform relatively poorly in terms of retention, especially that of pulps containing fillers, no doubt as a result of insufficient synergy between these copolymers and bentonite, which does not have much of a tendency to recoagulate.
[0010] In the document EP-A-0-235 893, it was proposed to use essentially linear cationic polyacrylamides having molecular weights of greater than one million, of thirty million and higher. This results in the obtainment of a retention effect that is satisfactory, but is still deemed inadequate in the papermaking application; since the use of bentonite causes problems during the subsequent treatment of the effluents issuing from the machine, users select this system only if there are significant advantages.
[0011] In the notes presented at the lecture given in Seattle on Oct. 11-13, 1989, published under the title “Supercoagulation in the control of wet end chemistry by synthetic polymer and activated bentonite,” R. Kajasvirta described the mechanism of supercoagulation of activated bentonite in the presence of a cationic polyacrylamide, without specifying its exact nature. This process has the same drawbacks as above.
[0012] Lastly, European Patent 0 574 335 produced an important improvement by proposing the use branched polymers (particularly polyacrylamides) in powder form.
[0013] The invention eliminates the drawbacks mentioned above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIGS. 1-10 are histograms showing the data obtained as a result of the analyses performed in Example 1.
[0015] FIGS. 11-20 are histograms showing the data obtained as a result of the analyses performed in Example 2.
DETAILED DESCRIPTION OF THE INVENTION
[0016] The object of the invention is to obtain an improved process of the type in question, which is comprised of adding to the suspension or fibrous mass or paper pulp to be flocculated, as the main retention aid, an agent consisting of or comprising a branched polyacrylamide which is characterized in that it has been prepared in reverse phase or water-in-oil emulsion, and bentonite as the second retention aid (a so-called “dual” system of the type also known as “microparticulate”).
[0017] The phrase “exists in reverse phase emulsion” or similar expressions related to the polymer used (i.e., injected or introduced into the pulp to be flocculated) according to the invention, will be understood by one skilled in the art to designate the reverse phase water-in-oil emulsion that is dissolved in water before its injection or its introduction into the mass or pulp to be flocculated (this dissolution in water results in what is known as the “reversal” of the initial reverse phase water-in-oil emulsion; these processes are well known to one skilled in the art).
[0018] The additions of the polymer and the bentonite are separated by a shearing stage, for example at the level of the mixing pump known as a “fan pump.” In this field, the reader is referred to the specification of U.S. Pat. No. 4,753,710, as well as to a vast body of prior art related to the addition point of the retention aid relative to the shearing stages existing in the machine, including U.S. Pat. No. 3,052,595; Unbehend, TAPPI Vol. 59, No. 10, October, 1976; Luner, 1984 Papermakers Conference or TAPPI, April, 1984, pp. 95-99; Sharpe, Merck and Co., Inc., Rahway, N.J., USA, around 1980, Chapter 5, “Polyelectrolyte Retention Aids”; Britt, TAPPI Vol. 56, October 1973, p. 46 ff.; and Waech, TAPPI, March, 1983, p. 137; or even U.S. Pat. No. 4,388,150 (Eka Nobel).
[0019] The reader is also referred to U.S. Pat. No. 4,753,710 for all of the generalities related to paper production, the usual additives used, and similar details.
[0020] It is possible to replace the bentonite, as the secondary retention aid, with a kaolin, as described in the Applicant's French patent application 95 13051, this kaolin preferably being pretreated with a polyelectrolyte. One skilled in the art can refer to this French patent application 95 13051.
[0021] This process makes it possible to obtain a distinctly improved retention of fines and fillers without a reverse effect. An additional characteristic of this improvement is that the drainage properties are improved.
[0022] The branched polyacrylamide (or more generally the branched (co)polymer) is introduced into the suspension, in a distinctly preferred way, in the form of a reverse phase water-in-oil emulsion at a rate of 0.03 to one per mill (0.03 to 1%, or 30 to 1,000 g/t) by weight of active material (polymer) relative to the dry weight of the fibrous suspension, preferably 0.15 to 0.5 per mill, or 150 to 500 g/t.
[0023] In a way that is known to one skilled in the art, the reverse phase emulsion polymer is diluted in water and inverted (solubized) by this dilution before its introduction, as described above.
[0024] This selection of the reverse phase emulsion form makes it possible, in the papermaking application for the retention of fillers and fines, to reach a level of performance unequalled up to now. Moreover, the utilization of branched polymers makes it possible to obtain a better retention of the bentonite in the sheet, as described in the above-mentioned European patent 0 574 335, and thus to limit its negative effects on the subsequent treatment of the effluents issuing from the machine. Furthermore, the choice of this branched polyacrylamide increases the fixation capacity of the bentonite in the sheet, consequently resulting in a synergy, and hence a recoagulation, which reduces the bentonite content in the white water.
[0025] It is understood that it is essential according to the invention that the polymer be prepared by means of a reverse phase oil-in-water emulsion polymerization. However, this polymer can then be used (i.e., injected or introduced into the mass or pulp to be flocculated) either in the form—preferably—of this reverse phase emulsion after its dissolution in water, or in the form of a powder obtained by drying (especially drying by means of “spray drying”) the reverse phase emulsion from the polymerization, and then redissolving this powder in water, for example at a concentration on the order of 5 g of active polymer/liter, the solution thus obtained then being injected into the pulp at substantially the same polymer dosages.
[0026] Advantageously, in practice, the branched (co)polyacrylamide is a cationic copolymer of acrylamide and of an unsaturated cationic ethylenic monomer, chosen from the group comprising dimethylaminoethyl acrylate (ADAME), dimethylaminoethyl methacrylate (MADAME), quaternized or salified by different acids and quaterinizing agents, benzyl chloride, methyl chloride, alkyl or aryl chloride, dimethyl sulfate, diallyldimethylammonium chloride (DADMAC), acrylamidopropyltrimethyaammonium chloride (APTAC), and methacrylamidopropyltrimethylammonium chloride (MAPTAC).
[0027] In a known way, this copolymer is branched by a branching agent constituted by a compound having at least two reagent groups chosen from the group comprising the double bonds, aldehyde bonds, or epoxy bonds. These compounds are well known and are described, for example, in the document EP-A-0 374 458 (see also the Applicant's document FR-A-2 589 145).
[0028] As is known, a “branched” polymer is a polymer that has in the chain branches, groups or branchings globally disposed in one plane and not in the three directions, unlike a “cross-linked” polymer; branched polymers of this type, of high molecular weight, are well known as flocculating agents. These branched polyacrylamides are distinguished from the cross-linked polyacrylamides by the fact that in the latter, the groups are disposed three dimensionally so as to lead to practically insoluble products of infinite molecular weight.
[0029] The branching can be carried out preferably during (or possibly after) the polymerization, for example by reaction of two soluble polymers having counter-ions, or by reaction on formaldehyde or a polyvalent metal compound. Often, the branching is carried out during the polymerization by the addition of a branching agent, and this method is clearly: preferred according to the invention. These processes for polymerization with branching are well known.
[0030] The branching agents that can be incorporated comprise ionic branching agents such as polyvalent metal salts, formaldehyde, glyoxal, or even, preferably, covalent cross linkers that will copolymerize with the monomers, preferably monomers with diethylenic unsaturation (like the family of diacrylate esters such as the diacrylates of polyethylene glycol PEG) or polyethylenic unsaturation, of the type classically used for the cross-linking of water-soluble polymers, and particularly methylenebisacrylamide (MBA), or any of the other known acrylic branching agents.
[0031] These agents are often identical to the cross linkers, but cross-linking can be avoided when desiring to obtain a polymer that is branched but not cross-linked, by optimizing polymerization conditions such as the concentration of the polymerization, type and quantity of transfer agent, temperature, type and quality of initiators, and the like.
[0032] In practice, the branching agent is methylenebisacrylamide (MBA), introduced at a rate of five to two hundred (5 to 200) moles per million moles of monomers, preferably 5 to 50.
[0033] Advantageously, the quantity of branched polyacrylamide introduced into the suspension to be flocculated is between thirty and one thousand grams of active polymer/ton of dry pulp (30 and 1,000 g/t), or between 0.03 per mill and one per mill, preferably 150 to 500 g/t; it was observed that if the quantity is lower than 0.03% (0.03 per mill), no significant retention is obtained; likewise, if this quantity exceeds 1% (1 per mill), no proportional improvement is observed; however, unlike the linear cationic polyacrylamides, as described in the documents EP-A-0 017 353 and EP 0 235 893 mentioned in the preamble, there is no observed reverse dispersion effect by recirculation in the closed circuits of the excess polymer not retained in the sheet. Preferably, the quantity of branched polyacrylamide introduced is between 0.15 and 0.5 per mill (0.15 and 0.5%) of the quantity of dry pulp, or between 150 g/t and 500 g/t.
[0034] As stated above, it is important that the branched polymer be prepared in reverse phase (water-in-oil) emulsion form in order to achieve the improvement of the invention. Emulsions of this type and the process for preparing them are well known to one skilled in the art.
[0035] This approach was condemned in the above-mentioned European patent 0 574 335, in which it was indicated that if a branched polymer is used in emulsion, the indispensable presence of surfactants in these emulsions promotes the formation of foams during the production of the paper and the appearance of disparities in the physical properties of the finished paper (modification of the absorbency in the places where part of the oil phase of the emulsion is retained in the sheet).
[0036] Therefore, it was not obvious to consider a fortiori the reverse phase water-in-oil emulsions whose oil content is clearly high.
[0037] The invention was even more difficult to achieve in that it was important to stay within the field of branched polymers and not to cross over to the field of cross-linked polymers. It is known that technically, especially on an industrial production scale, the borderline between the two areas is very easily crossed, in a way that is, moreover, irreversible. Since the branched area is very limited, the difficulty of developing the invention is considerable, and the Applicant deserves credit for undertaking to use of this technology in the field of paper production, which poses particular problems and has strict quality requirements.
[0038] The risk of failure, which may explain the fact that this technology had not been used, was even greater in that cross linked emulsions are not known to provide any particular advantage in paper.
[0039] In comparison with the linear polymers, the branched polymers in powder form of the above-mentioned European patent 0 574 335 had already made substantial progress relative to the properties and the paper production process. The improvement was on the order of 20 to 40% depending on the properties.
[0040] With the present branched emulsions, an improvement on the order of 50 to 60% is obtained., which would not have been foreseeable since, on the contrary, it was known that the cross linked products did not work.
[0041] According to the invention, in a preferred but non-limiting way, a “moderately branched” polymer is used, for example with 10 ppm of branching agent relative to the active material.
[0042] As already indicated above, the polymer can be used either in the form of its synthetic reverse-phase emulsion, dissolved or “inverted” in water, or in the form of the solution in water of the powder obtained by drying said synthetic: emulsion, particularly by means of spray-drying. Spray-drying is a process that is also known to one skilled in the art. The reader is referred to the tests below in order to verify that the results are comparable.
[0043] Bentonite, also known as “smectic swelling clay,” from the montmorillonite family, is well known and there is no need to describe it in detail here; these compounds, formed of microcrystallites, comprise surface sites having a high cation exchange capacity capable of retaining water (see for example the document U.S. Pat. No. 4,305,781, which corresponds to the document EP-A-0 017 353 mentioned above, and FR-A-2 283 102).
[0044] Preferably, a semisodic bentonite is used, which is introduced just upstream from the headbox, at a rate of 0.1 to 0.5 percent (0.1 to 0.5%) of the dry weight of the fibrous suspension.
[0045] As a filler, it is possible to use kaolins, GCC or ground CaCO 3 , precipitated CaCO 3 or PCC, and the like.
[0046] The branched polymer in reverse phase emulsion according to the invention is injected or introduced prior to a shearing stage into the paper pulp (or fibrous mass to be flocculated), which is more or less diluted according to the experience of one skilled in the art, and generally into the diluted paper pulp or “thin stock,” i.e. a pulp diluted to about 0.7 to 1.5% solid matter such as cellulose fibers, possible fillers, and the various additives commonly used in papermaking.
[0047] According to a variant of the invention with fractionated introduction, some of the branched polymer in emulsion according to the invention is introduced at the level of the stage for preparing the “thick stock” with about 5% or more solid matter, or even at the level of the preparation of the thick stock before a shearing stage.
[0048] The following examples illustrate the invention without limiting its scope.
EXAMPLE 1
[0000] Production of a Branched Polymer in the Form of a Reverse Phase Water-in-Oil Emulsion
[0049] In a reactor A, the constituents of the organic phase of the emulsion to be synthesized are mixed at the ambient temperature.
a) Organic phase
252 g of Exxsol D100 18 g of Span 80 4 g of Hypermer 2296
b) In a beaker B, the aqueous phase of the emulsion to be produced is prepared by mixing:
385 g of acrylamide at 50% 73 g of ethyl acrylate trimethyl ammonium chloride 80% 268 g of water 0.5 g of methylenebisacrylamide at 0.25% 0.75 ml of sodium bromate at 50 g l −1 20 ppm of sodium hypophosphite relative to the active material 0.29 ml of Versenex at 200 g l −1
[0062] The contents of B are mixed into A under agitation. After the mixing of the phases, the emulsion is sheared in the mixer for 1 minute in order to create the reverse phase emulsion. The emulsion is then degassed by means of a nitrogen bubbling; then after 20 minutes the gradual addition of the metabisulfite causes the initiation followed by the polymerization.
[0063] Once the reaction is finished, a “burn out” (treatment with the metabisulfite) is carried out in order to reduce the free monomer content.
[0064] The emulsion is then incorporated with its inverting surfactant in order to subsequently release the polymer in the aqueous phase. It is necessary to introduce 2 to 2.4% ethoxylated alcohol. The standard Brookfield viscosity of said polymer is 4.36 cps (viscosity measured at 0.1% in a 1.M NaCl solution at 25° C. at sixty rpm).
[0065] In accordance with a variation of the MBA content from 5 to 20 ppm, the results in terms of UL viscosity are the followings
[0066] Table of Example 1:
MBA NaH 2 PO 2 UL IR(1) IVR(2) Test ppm ppm(*) Viscosity (%) (%) State R 52 5 20 4.56 12.8 0 Branched R 102 10 20 3.74 28.9 0 Branched SD 102 10 20 3.70 26 0 Branched X 104 10 40 2.31 45 50 Cross- linked X 204 20 40 2.61 54.8 50 Cross- linked EM 140CT 0 15 4.5 0 <0 Linear EM 140L 0 30 3.82 0 0 Linear EM 140LH 0 40 3.16 0 <0 Linear EM 140BD 5 0 1.85 80 100 Cross- linked FO 4198 5 20 3.2 5 <0 Branched FO 4198: a branched powder containing 20 ppm transfer agent and 5 ppm branching agent. (*)sodium hypophosphite, transfer agent (1)ionic regain in % (2)intrinsic viscosity regain in % EM140CT: a standard emulsion of very high molecular weight containing no branching agent EM 140L: a standard emulsion of high molecular weight containing no branching agent EM140LH: an emulsion of average molecular weight containing no branching agent EM140BD: a cross-linked emulsion containing no transfer agent and 5 ppm cross linker SD 102: the emulsion R 102 dried by spray-drying, and the powder obtained dissolved in water to 5 g of active polymer/liter
[0067] It is noted that the linear products do not develop any ionic regain IR, and their intrinsic viscosity IV decreases under the effect of an intense shearing (two of the IV values are negative); the branched products in emulsion develop an ionic regain IR, but no IV (values <=0); the cross-linked products develop a high ionic regain and a very high IV regain.
[0000] Definitions of the Ionic Regains and Intrinsic Viscosity Regains:
[0000] Ionic regain IR=(X−Y)/Y×100
[0000] with X: ionicity after shearing in meq/g.
[0000] Y: ionicity before shearing in meq/g.
[0000] Intrinsic viscosity regain IVR=(V1−V2)/V2×100
[0000] with V1: intrinsic viscosity after shearing in dl/g
[0000] V2: intrinsic viscosity before shearing in dl/g
[0068] Some of the emulsions cited above will be the subjects of a study of effectiveness in retention and drainage in an automated sheet former at the Center for Paper Technology.
[0000] Procedure for Testing the Emulsions
[0069] Pulp Used:
mixture of 70% bleached hardwood kraft KF 10% bleached softwood kraft KR 20% mechanical pulp PM 20% natural calcium carbonate.
Sizing in a neutral medium with 2% of an alkyl ketene dimer emulsion.
[0071] The pulp used is diluted to a consistency of 1.5%. A sample of 2.24 dry g of pulp, or 149 g of pulp at 150%, is taken, then diluted to 0.4% with clear water.
[0072] The 560 ml volume is introduced into the plexiglass cylinder of the automated sheet former, and the sequence is begun.
t = 0 s, start of agitation at 1500 rpm. t = 10 s, addition of the polymer. t = 60 s, automatic reduction to 1000 :rpm and, if necessary, addition of the bentonite. t = 75 s, stopping of the agitation, formation of the sheet with vacuum under the wire, followed by reclamation of the white water.
[0073] The following operations are then carried out:
measurement of the turbidity of the water under the wire. dilution of a beaker of thick stock for a new sheet with the reclaimed water under the wire. drying of the so-called 1st pass sheet. start of a new sequence for producing the so-called 2nd pass sheet.
[0078] After 3 passes, the products to be tested are changed.
[0079] The following analyses are then performed:
measurement of the matter in suspension in the water under the measurement of the ash in the sheets (TAPPI standard: T 211 om-93) measurement of turbidity 30′ after the fibers are deposited in order to learn the state of the ionic medium. measurement of the degree of drainability of the pulp with a Canadian Standard Freeness (CSF; TAPPI standard T 227 om-94).
Notes for Tables (I) and (II) below:
X=so-called first-pass measurement
R1=so-called second pass-measurement (1st recycling)
R2=so-called third pass measurement (2nd recycling)
Ash % _% by weight of ash retained (=filler retention) in the sheet/weight of the sheet.
Comments on the Results: See Tables W and (TIC) Below Relative to Example 1, and FIGS. 1 Through 10 , which Represent the Corresponding Histograms
[0084] The cross-linked polymers have no advantage as to the flocculation and the retention of fines and. fillers in spite of the high rate of shear applied during the process to the fibrous mass (and not applied to the polymer itself), in this case 1,500 rpm, which is characteristic of this type of microparticulate retention systems They show a poor capture of fillers and colloidal matter, since no reduction in turbidity is observed.
[0085] The combination with bentonite does not significantly improve the effectiveness in terms of retention and only slightly improves the effectiveness in terms of drainage.
[0086] As for the linear polymer, its behavior follows the tendency to improve the retention of fillers and fines.
[0087] The combination according to the invention of a branched polymer in reverse phase emulsion and bentonite provides a net gain in filler retention and in total retention, and is revealed to be superior to the known linear polymer/bentonite system.
[0088] The coagulation capacity is better for a branched polymer in emulsion, which translates into an excellent reduction in the turbidity at 30′ (30 min.).
[0089] The R 52 test and the R 102 test show that the invention makes it possible to obtain branched products having UL viscosities higher than those accessible through gel polymerization as described in European patient 0 574 335. Any attempt to reach such highly advantageous UL viscosity values using a gel polymerization process with drying into a powder would result in a product that was totally insoluble and therefore totally unusable in the industry.
[0090] The SD 102 test shows that the polymer used in the form of a solution in water of the powder obtained by drying the reverse phase emulsion from the synthesis of the polymer behaves like the polymer used in the form of the solution in water of said synthetic reverse phase emulsion. In particular, no degradation of the polymer is observed during the stage for drying by means of spray-drying.
[0091] It is useful to compare the R 52 test to the FO 4198 test (powder), since the-polymers have the same chemistry, hence the same cationicity, and the same % of MBA, while the R52 of the invention is far superior to the powder in terms of drainage and retention (96.3 as compared to 87.6); compare also the turbidity in NTU after 30 minutes, 32 as compared to 75 NTU units.
[0092] Such UL viscosity values specifically result in substantially improved drainage.
[0093] The invention also relates to a novel retention aid for the production of a sheet of paper, paperboard or the like, which is comprised of a branched acrylic (co)polymer as described above, in reverse phase emulsion, which is characterized in that its UL viscosity is >3, or >3.5 or >4. Said agent can be used either in emulsion, inverted in water, or in a solution of the powder obtained by drying the emulsion, as described above.
EXAMPLE 2
[0000] Production of a Branched Acrylamidopropyltrimethylammonium Chloride (APTAC) Based Polymer in the (Corm of a Reverse Phase Oil-in-Water Emulsion:
[0094] In a reactor A, the constituents of the organic phase of the emulsion to be synthesized are mixed at the ambient temperature.
a) Organic phase
252 g of Exxsol D100 18 g of Span 80 4 g of Hypermer 2296
b) In a beaker B, the phase of the emulsion to be produced is prepared by mixing:
378 g of acrylamide at 50% 102.2 g of acrylamidopropyltrimethylamonium chloride (60%) 245.7 g of water 0.5 g of methylenebisacrylamide at 0.25% 0.75 ml of sodium bromate at 50 g/l 20 ppm of sodium hypophosphite relative to the active material 0.29 ml of Versenex at 200 g/l
[0107] The contents of B are mixed into A under agitation. After the mixing of the phases, the emulsion is sheared in the mixer for 1 minute in order to create the reverse-phase emulsion. The emulsion is then degassed by means of a nitrogen bubbling; then after 20 minutes, the gradual addition of the metabisulfite causes the initiation followed by the polymerization.
[0108] Once the reaction is finished, a “burn out” is carried out in order to reduce the free monomer content.
[0109] The emulsion is then incorporated with its inverting surfactant in order to subsequently free the polymer in the aqueous phase.
[0110] Table of Example 2:
MBA NaH 2 PO 2 UL IR (1) IVR (2) Test PPM ppm(*) viscosity (%) (%) State M 52 5 20 4.20 14.2 0 Branched M 102 10 20 3.34 21.3 0 Branched XM 104 10 40 2.11 37 50 Cross- linked XM 204 20 40 1.94 58 55 Cross- linked EK 190 0 15 4.35 0 0 Linear EK 190 5 0 1.85 78 60 Cross- BD linked EK 190: a standard emulsion of a copolymer of acrylamide and crylamidopropyltrimethylammonium chloride, linear.
Procedure for Testing the Emulsions
(identical to that of Example 1)
Comments on the Results: See Table (III) Below Relative to Example 2, and FIGS. 11 Through 20 , which Represent the Corresponding Histograms
[0112] The results invite the same comments as those of Example 1 and confirm the great advantage of the present invention.
[0113] The invention also relates to the novel retention aids described above, characterized in that they consist of, or comprise, at least one branched (co)polymer of the type described, prepared in reverse phase emulsion, intended to cooperate with a secondary retention aid after an intermediate stage for shearing the paper pulp, as well as to the processes for producing sheets of paper, paperboard or the like using the agents according to the invention or the process according to the invention, and the sheets of paper, paperboard and the like thus obtained.
[0114] Said agent can be used either in emulsion inverted in water, or in a solution of the powder obtained by drying the emulsion, as described above. | The invention concerns an improved method for making paper, which uses a branched polymer prepared in invert emulsion as the main retention agent, and bentonite as a secondary retention agent (dual type system). The two additions are separated by a step for shearing the fibrous suspension (or mass). The invention results in highly improved retention and also highly improved dewatering. Moreover, it enables the bentonite content in white water to be reduced. | 3 |
FIELD AND BACKGROUND OF THE INVENTION
[0001] The present invention relates in general to superconductors and, in particular, to a new and useful apparatus and method of making cable-in-conduit-conductors or CICC's.
[0002] Superconducting cables integrated into a metal jacket can be used as windings of coils which create very strong magnetic fields. At present, two previous methods are known to the inventors for the commercial manufacture of such Cable-In-Conduit-Conductor (CICC). The first method involves conventional cable handling equipment used in conjunction with seam welded tube manufacturing equipment. The second method relies upon pre-manufactured tubing, cable and a die block to produce the final product. Each of these prior art methods will be described in greater detail below.
[0003] In the first method, superconducting cable is creates a continuous length coil which is, in turn, loaded in a cable payout machine. A metal jacket material, in coiled strip form, is also provided to act as strip material. The jacket material is positioned directly under the superconducting cable proximate the payout machine. The cable and jacket materials are simultaneously fed into a series of rolls in a tube-forming mill. The forming rolls of the mill bend and roll the strip material around the cable to form an encasing tube. The tube is then subjected to a seam welding process so that the edges of the strip material of the jacket are joined to produce a leak tight tubular product. Additional forming rolls after the welding process reduce the diameter of the tube, forcing the strip material into intimate contact with the superconducting cable. Keeping in mind that the shape of the conductor can aid the winding process of the final coil, further forming processes may be used to form the jacket material into a square, oval, rectangular or other cross section as required by the conductor design specification, and the final CICC product is wrapped onto a storage spool until the coil winding process begins (see below).
[0004] A major drawback of this first method involves the welding process required, insofar as the superconducting cable may be damaged during this welding. Consequently, the first method described above typically results in CICC product of lower quality in comparison to other known manufacturing processes.
[0005] The second method uses pre-manufactured lengths (typically 20 ft.) of either welded or seamless tubing as the jacket material. The jacket material is stacked vertically in a equilateral triangular rack. Superconducting cable is then provided as a continuous length coil which is pulled through the hollow center of the jacket material. This cable pulling operation is started at the bottom of the rack and progresses upward in a helical fashion through each subsequent layer of tubes until the stringing operation is complete. Removing the first two tube sections from the bottom of the rack begins forming of the CICC. The tubes are slid together and joined by an orbital butt weld (over the cable) to produce a leak tight joint. The tubing is then pulled through a die (or series of dies) to produce the desired final shape. Once formed, the final product is wrapped onto a storage spool.
[0006] A significant disadvantage of this second manufacturing process results from its rack assembly. The orientation of the rack can limit the efficiency of the manufacturing operation.
SUMMARY OF THE INVENTION
[0007] The present invention is drawn to a system for fabricating a cable-in-conduit-conductor. The system has a work surface with superconductor cable distribution means situated on one end of the surface. This distribution means will also serve to guide the cable through a tube placed on the work surface, thereby creating a portion of cable encased within tube. Drum means are located on opposite sides of the work surface, and these serve to assist in bending and redirecting the cable without damaging it. Notably, the cable is bent around the first drum means and returned to across the work surface without pulling the cable through any additional tubes, thereby creating a naked length of cable. In contrast, the second drum means is capable of guiding the naked length of cable into additional tubes on the work surface, thereby creating additional portions of cable encased within tube. Finally, tension means and compression means work together to process the cable encased within tube into a single length of cable-in-conduit conductor (CICC). Additional items, such as collection means for collecting the CICC and/or orbital butt welding apparatus, may also be provided.
[0008] The present invention also contemplates a method for creating CICC. Essentially, this method includes pulling a superconductor cable through an appropriate tube situated on a work surface, bending and returning the exposed cable along the work surface, bending and pulling the cable back through a separate tube and finally compressing the cable encased in tube portions to eliminate the exposed lengths of cable while, at the same time, joining each section together. As above, this joining operation may be performed via orbital butt welding, and the pulling and returning operations can be performed numerous times until the desired length of CICC product is produced.
[0009] 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
[0010] In the drawings:
[0011] [0011]FIG. 1 is a plan view of an apparatus for fabricating a CICC during a first step of the process;
[0012] [0012]FIG. 2 is a view similar to FIG. 1 during a second step of the process;
[0013] [0013]FIG. 3 is a view similar to FIG. 1 during a third step of the process;
[0014] [0014]FIG. 4 is a view similar to FIG. 1 during a fourth step of the process;
[0015] [0015]FIG. 5 is a view similar to FIG. 1 during a fifth step of the process;
[0016] [0016]FIG. 6 is a view similar to FIG. 1 during a sixth step of the process;
[0017] [0017]FIG. 7 is a view similar to FIG. 1 during a seventh step of the process;
[0018] [0018]FIG. 8 is a view similar to FIG. 1 during an eighth step of the process;
[0019] [0019]FIG. 9 is a view similar to FIG. 1 during a ninth step of the process; and
[0020] [0020]FIG. 10 is a view similar to FIG. 1 during a final step of the process.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] The present invention is a folded manufacturing process and apparatus for efficiently producing very long lengths of CICC using shorter lengths of pre-manufactured welded or seamless tubing in comparison to previously known methods.
[0022] The initial stage of process is illustrated in FIG. 1. The tubing used to jacket the intended CICC product may comprise individual lengths, or the tubing may be made up of a series of tubes welded into tube assemblies 12 . In either case, the tubing 12 is of the type used for superconductor construction, and it is most preferably oriented on a horizontal work surface or table 10 . Cable management drums 16 a , 16 b are provided at opposite ends of the table.
[0023] Notably, drums 16 serve three primary functions. First, these drums control the minimum bending radius of the superconductor cable so as not to induce work hardening and thereby lower the RRR value of the cable. Second, the drums provide a means of controlling the position of the cable during the stringing and pulling operations. Third, the hairpin turn caused by wrapping cable 14 around drum 16 eliminates any twisting of the cable that would tend to change the twist pitch of strands within the cable bundles of the super conductor cable 14 .
[0024] The superconductor cable 14 used in this invention most typically comprises a plurality of smaller cable wires or strands that are twisted together at a specified twist pitch and bundled into a unitary element hereafter referred to simply as superconductor cable 14 . Superconductor cable 14 supplied by a payout spool 15 at one edge of the table 10 . As with the tubing mentioned above, those familiar in the superconducting arts will readily appreciate the range of appropriate materials.
[0025] In order to create CICC according to the present invention, superconductor cable 14 is pulled through one of any number of tube assemblies 12 . In effect, this pulling operation will serve to surround the cable with the tubing. Once the cable exits the end of assembly 12 a , it is wrapped in a hairpin fashion around cable management drums 16 a.
[0026] Once the first hairpin turn is completed, the leading edge of cable 14 is returned back down the table 10 to the end with payout spool 15 . During this returning step, the cable is positioned between or proximate to the tube assemblies 12 , rather than inside of them. The purpose of this “naked length” cable return operation is to allow the tube assemblies 12 to be indexed across the table for processing. It also prevents the need to rotate or flip the assemblies 12 in order to align the mating ends of each assembly (see below).
[0027] After the cable 14 has been returned to the payout-spool-end of the table, it is also wrapped in a hairpin fashion around drum 16 b for the same reasons outlined above. The cable pulling process is then repeated, with the cable 14 being pulled through a different tube assembly 12 and then back down the table as a “naked length”. As above, the cable 14 must be wrapped around the drums 16 a , 16 b , and the pulling and returning processes are repeated until all of the superconducting cable is on the work table (i.e., one half of the cable length being housed in tube assemblies and remaining half interposed between the drums 16 a , 16 b as naked lengths).
[0028] The CCIC is actually formed during the milling step of the operation. This step involves feeding the first or last tube assembly/pulled cable combination upon which a pulling cable operation was performed (along with the subsequent naked length of cable, as well as all the remaining tube/cable combinations and associated naked cable lengths) into a tube forming mill 18 , or series of die blocks known to those skilled in the art.
[0029] Forming mill 18 (or die blocks) reduces the diameter of the tubing assembly 12 around the cable 14 into a unitary conductor in which the cable and the tubing are in intimate contact. Forming mill 18 also shapes the conductor into a final, desired profile (typically either a square or rectangle). The finished conductor is wrapped on a storage spool 20 for future use/processing.
[0030] As the milling process progresses, the both the cable and tubing diameter will be reduced and a corresponding elongation in the length of each develops. However, this rate of elongation will be greater for the tubing in comparison to the cable because the tubing undergoes more compression within the mill relative to the cable (stated differently, the cable is unaffected by mill forming until it reaches the roll or die set that actually forces the tubing down onto the cable).
[0031] More importantly, the tubing will elongate backwards along the length of the cable during the milling process. However, a kink or sharp bend in the cable would cause irreparable harm to the cable because such an impediment would prevent the passage of the elongated tubing over the cable. Therefore, means to prevent such kinking must be employed in order for the invention to function efficiently.
[0032] Ideally, this means for preventing kinking comprises a combination of a cable tensioning device 26 (CTD), a cable “soft clamp” device (CSCD) 22 and a cable inlet/outlet guide device (CIOGD) 30 . CTD 26 applies tension to the cable 14 during processing while allowing the cable to move forward into mill 18 at the appropriate speed. However, for CTD 26 to function properly, cable 14 must be firmly anchored in order to counteract the applied tension of the CTD 26 in way that does not damage the cable. Accordingly, CSCD 22 is provided to clamp and stay the cable in place. Finally, CIOGD 30 is used to allow relative motion between the cable 14 and the outermost edge of the backwards-elongating tube end between tensioning operations (i.e., during milling). The CIOGD 30 should operate in a manner that does not cut or damage the cable 14 .
[0033] [0033]FIG. 2 illustrates the relative positioning of the tube assemblies and other elements after almost all of the first tube assembly 12 a has been mill processed. Note that the remaining cable 14 (i.e., the cable which has not yet been milled) is removed from CTD 26 and soft clamp device 22 via loop 29 (see below).
[0034] The slack removal step should be performed next, as seen in FIG. 3. Essentially, in this step, loop 29 is used to capture the naked length of cable 14 and then moved in the opposite direction from the pulling operation (i.e., toward mill 18 ) so as to draw the next tube assembly 12 proximate to the portion of tube assembly 12 a that has not yet been milled, thereby eliminating the naked length cable between the first tube assembly 12 a and the second tube assembly. Once the second tube assembly is proximate to the first, almost completely milled tube assembly 12 a , the two are joined together to form a leak tight seal 13 using an orbital butt weld or any other appropriate means for joining the tubing assemblies 12 . Preferably, this slack removal step (as well as the welding) is performed prior to further milling of subsequent tube assemblies, thereby simplifying the welding/joining procedure.
[0035] Ideally, the weld is a full penetration butt weld. Such a weld can be formed without damaging the underlying cable through the use of a consumable centering device. Such a device may include, but is not limited to, a corrugated foil or other such implements known in the art. A corrugated foil having dimensions of 0.001″×1.5″×2″ seems to work particularly well. The foil is wrapped around the cable and inserted between the cable and either tubing assembly prior to butt welding so as to protect the cable. As the name implies, the foil is consumed during the welding operation, thereby avoiding formation of any significant irregularities in the final CICC product.
[0036] As seen in FIG. 4, the second tube assembly is processed through the tube forming mill or die blocks (FIG. 4) and taken up on the storage spool 20 . The process is repeated until the desired length of CICC has been fabricated. For the sake of completeness, these subsequent milling and slack removal steps are shown in FIGS. 5 - 10 .
[0037] During the forming operation of each tube/tube assembly, the tensioning device 26 and soft clamp device 22 are used to control the amount of back tension applied to the end of the cable exiting the tube being formed. Tension is applied to keep the cable taut, allowing the tubing to slide backward along the cable as it elongates from the forming operation.
[0038] The soft clamp 22 holds the cable in a fixed position to provide the resistance necessary for operation of CTD 26 . The soft clamp also monitors the load being applied to the superconductor cable and can be equipped with automated monitors that would shutdown the process in the event of over-tensioning and before the cable was damaged. Cable carriage 24 can be used in conjunction with softclamp 22 and CTD 26 to provide further safeguards against damaging the cable. As will be appreciated by those familiar with the art, CICC cables must have consistent and uniform construction for proper operation.
[0039] The work surface 10 can be constructed of any materials that adequately support the tubing 12 and cable 14 . The tubes/cable can be positioned either vertically or horizontally, provided they are properly supported and the remaining elements of the invention are appropriately aligned.
[0040] The process can produce straight length sections of a specified length or a continuous length product accumulated on a storage spool. The pulling/shaping operation of the CICC can be done with a forming mill or drawn through a fixed die (or set of dies).
[0041] The individual length of the tubing assemblies 12 are determined by (1) the length of the manufacturing facility, and (2) the shipping limitations for incoming products. Similarly, the spatial constricts of the manufacturing facility will ultimately determine the intermediate length of the tubing prior to the insertion of the cable, although a table 10 is expected to have a length anywhere from eighty feet to several hundred feet.
[0042] For straight length tubing, the current maximum allowable shipping length is 100-120 feet. If the material is received as a coil, the length is limited by the tubing manufacturer's coiling process, although it is expected that this length could easily be exceed 1,000 feet.
[0043] One of the key advantages of this invention is that the process can be easily modified to suit the incoming material length. In turn, straight tubular sections can have any length, so long as the manufacturing facility permits, and tubing can be purchased in straight lengths of up to 100-120 feet, or in coil form (straightened once at the site) as long as required. This procedure, along with the use of a seamless tubular product, significantly reduces the number and total linear feet of welds in the final product. A reduction in the number of and length of welds significantly reduces costs, as well as the potential for damage to the relatively fragile superconductor cable itself. Furthermore, to the extent that CICC must be durable and leak resistant (in order to create a barrier for the liquid helium), the ability to limit the number and total linear feet of welds should also significantly enhance the quality of the product.
[0044] Additionally, this process enables the production of very long lengths of CCIC within a facility of any size. In turn, this reduced facility footprint will markedly reduce costs (in terms of construction and/or maintenance of the physical plant).
[0045] Because the primary limiting factor of this method is based upon the length of the table 10 , it is possible to construct large lengths of tubing assemblies via orbital welding prior to pulling the superconducting cable through these assemblies. By way of example rather than limitation, if a 300 foot work surface were provided, one could arrange ten groupings of three 100 foot straight tubes. Each set of three would be welded prior to the pulling operation (resulting in 20 welds being performed without the cable in place), and only 9 additional welds would be required using this method (and yields a final CICC product of over 3,000 feet in length).
[0046] Likewise, if a single piece, non-tubular jacket material is used, obviously that material must be joined together (via welding) in order to form a tube assembly that can be integrated into a CICC product (see above for prior art methods of using such material). In the previously known methods, the welding was by necessity performed in close proximity to the superconducting cable. However, in the present invention, the tubes can be preformed on-site prior to the cable pulling operation (with reference to the example above, the non-tubular jacket material is formed into tubes that would be incorporated into the example above).
[0047] In either case, it becomes plain to see that, using this procedure, a vast majority of the inspection, repair and removal of defective welds can be done without any risk of damage to the superconducting cable. Given that any weld made over the superconductor necessarily puts the entire length of conductor at risk to damage or loss (since the superconductor cable cannot be spliced or repaired if damaged by the welding process), another advantage of this invention is its ability to construct large lengths of CICC with minimal risk to the cable itself.
[0048] Yet another advantage of the present invention resides in its unique ability to create long lengths of CICC without the need to rotate or align mating ends of the tube assemblies during construction. Stated differently, by alternating the pulling of cable inside of a tube and then continuously returning the cable as a naked length, tubes that are longer in length than the actual facility in which they are processed can be made without the further manipulation of the assemblies. In contrast, previously known methods (especially the aforementioned rack-assembly method described above) were not capable of running the assemblies through the process without the physical manipulation and further alignment of specific ends of the tube assemblies.
[0049] Thus, in the present invention, the combination of the 2 hairpin turns used during the superconductor stringing eliminates the twist created if it were wrapped around a spool hub. Elimination of this spool hub prevents any change to the twist pitch of the cable strands that might adversely effect the performance of the resulting CICC product.
[0050] 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. | An system and method for fabricating a cable-in-conduit-conductor for use in superconductor application is described. The system utilizes a work surface with drum means provided at each end. A superconductor cable is fed from a supply source at one end. After the cable is pulled through a tube on the work surface, the leading edge of the cable is bent around one of the drums and returned to the opposite end of the table. This naked length of cable is once again bent around one of the drums and then pulled through another tube on the table. This process is repeated until an acceptable length of superconductor cable is present. Tension means are used in conjunction with a tube mill which compresses the tube-cable combination into a viable cable-in-conduit conductor (CICC). Notably, as this tension-compression is occurring, the naked lengths of cable are eliminated and each separate tube section is joined together to create a uniform CICC. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to rubber compositions and has particular reference to rubber compositions suitable for use in the manufacture of steel-belted automobile tires.
2. Prior Art
Steel-belted tires are in widespread use for their inherent advantages of good driving stability, high wear resistance and other superior physical properties compared to conventional tires. Research, efforts have been focused, inter alia, on improving the of adhesion between rubber layers and steel cords which has an important bearing upon the quality of the tires. This adhesion parameter determines the service life of the tire exposed to various environmental conditions during and subsequent to its processing stage and shipment to the end user. In the manufacture of a steel-belted tire, the starting rubber possesses sufficient "initial adhesion" with steel cords at the time of vulcanization. Unvulcanized rubber, however, is susceptible to absorption of moisture and hence its adhesive property, namely "unvulcanized moisture resistant adhesion", tends to decline upon vulcanization. Vulcanized rubber is also liable to suffer a reduction in its adhesive property, namely "vulcanized moisture resistant adhesion", due to penetration of moisture in the air through the rubber layer into the steel cords during the use of tire. It is further possible that if the tire receives cuts, nail punctures and other damage to its tread portion during running of the automobile, which will allow permeation of water therethrough, this water is warmed up by the heat generated in the running tire and flows through the interstices of the steel cords, causing the rubber to separate due to a loss of its adhesive property; namely "vulcanized warm water resistant adhesion".
The terms quoted above represent all aspects of the adhesive property required of rubber compositions for steel-belted tires.
Various tire rubber composition are known which are capable of meeting some, but not all of the above adhesion requirements.
The vulcanization process in the manufacture of steel-belted tires holds the key to productivity as a whole. Vulcanization time can be shortened by increasing its temperature. However, conventional rubber compositions containing cobalt salts of organic acids, though believed conducive to adhesion with steel cord, are liable to suffer a decline in their "unvulcanized moisture resistant adhesion", "vulcanized moisture resistant adhesion" and "vulcanized warm water resistant adhesion" because of the higher vulcanization temperature.
It is known to choose high hardness and high modulus rubbers to cover hard steel cords for steel-belted tires. Such hard rubbers often incorporate large quantities of sulfur and carbon black and exhibit increased hardness and modulus upon vulcanization. At the same time, however, they tend to deteriorate in tensile strength and breaking extension.
SUMMARY OF THE INVENTION
With the foregoing difficulties of the prior art in mind, the present, invention seeks to provide rubber compositions that will have enhanced adhesive strength with respect to steel cords in terms of "initial adhesion", "unvulcanized moisture resistant adhesion", "vulcanized moisture resistant adhesion" and "vulcanized warm water resistant adhesion", with all these adhesive properties being retained even using high temperature vulcanization. Further that they will possess high hardness and excellent breaking extension property.
The inventive rubber compositions are therefore particularly useful and effective in coating the steel cords used in steel-belted tires.
The rubber composition according to the invention comprises 100 parts by weight of a starting rubber, and, based on the rubber, 1.0-5 parts by weight of partial condensates of hexamethylolmelamine pentamethylether 0.5-5 parts by weight of a cresol resin 4-7 parts by weight of sulfur and 0.1-0.8 parts by weight of a cobalt salt of organic acid based on the amount of cobalt element.
DETAILED DESCRIPTION OF THE INVENTION
The rubber composition of the invention essentially comprises the following components.
i) Starting Rubber
Natural rubber (NR) alone or in combination with synthetic isoprene rubber (IR).
ii) Partial Condensates of Hexamethylolmelamine Pentamethylether of the Formula ##STR1##
These partial condensates are commercially available such as for example Sumicanol 507 (tradename of Sumitomo Chemicals Co., Ltd.) which contains 50% of hexamethylolmelamine pentamethylether partial condensates. Other polymethoxymethylolmelamines for example hexamethoxymethylmelamine are not eligible for the purpose of the invention. The hexamethylolmelamine pentamethylether according to the invention should be used in an amount of 1.0-5 parts by weight per 100 parts by weight of the starting rubber. Smaller amounts than 1.0 weight parts would result in insufficient rubber hardness, and larger than 5 weight parts would lead to reduced breaking extension.
iii) Cresol Resin
This may be one readily available in commerce and is preferably meta-cresol resin which should be used in an amount of 0.5-5 parts by weight per 100 parts by weight of the starting rubber. Less than 0.5 weight part would result in insufficient rubber hardness, and more than 5 weight parts would lead to reduced breaking extension and to objectionably increased heat in vulcanized rubber.
iv) Sulfur
The amount of sulfur to be added should be 4-7 parts by weight per 100 parts by weight of the starting rubber. Less than 4 weight parts would be ineffective, while more than 7 weight parts would result in bloomed rubber surface.
v) Cobalt Salts of Organic Acid
Typical examples include straight chain or branched cobalt salts of monocarboxylic acid having a carbon number of 50-20 such as cobalt naphthenate, cobalt stearate, cobalt octylate and cobalt oleate. These cobalt salts should be added in an amount of 0.1-0.8 weight parts in terms of cobalt element per 100 weight parts of the starting rubber. Departures from this range would serve no useful purposes.
vi) Other Additives
There may be used other suitable additives such as carbon black, a vulcanization accelerator and the like depending upon the particular application for the rubber composition.
Comparative and Inventive Examples
For purposes of brevity, the formulations of the various rubber compositions for the Comparative Examples and Inventive Examples are shown in Tables 1 and 2 respectively along with their respective test results.
Metal Adhesion Test
1) Initial Adhesion
Brass plated steel cords (1×5 strand) spaced 12.5 mm apart in parallel were coated from both sides with each of the rubber compositions into a 25 mm wide web which was subsequently vulcanized at 170° C. for 20 minutes. The resulting test sample was subjected to drawing of the steel cords in accordance with the procedures of ASTM:D2229. Draw strength (index) and rubber coat percentage (%) were measured to determine the "initial adhesion" of the rubber composition.
2) Vulcanized Warm Water Resistant Adhesion
The test sample was immersed in 70° water with lower end cords cut and thus disposed for four consecutive weeks, followed by drawing of the cords.
Separation Test
A tire fabricated with a belt layer consisting of steel cords coated with each of the rubber compositions was inflated to an air pressure of 1.2 kg/cm 2 and run on a test drum set with slip angle of ±3°, camber angle of 2° and load of 127% (JATMA standards) at a speed of 60 km/hr for a distance of 6,000 km. The tire was dismantled, and the extent or amount of separation of an end portion of the belt layer was measured, in which instance the value in Comparative Example 2 was taken as a reference index. Test results are better the smaller the index value.
TABLE 1__________________________________________________________________________ Comparative Examples 1 2 3 4 5 6 7__________________________________________________________________________natural rubber (RSS #1) 100 100 100 100 100 100 100carbon black (HAF) 60 60 60 60 60 60 60zinc oxide 10 10 10 10 10 10 10aging inhibitor 1 1 1 1 1 1 1(phenylenediamine)cobalt-naphthenate *1 3 3 3 3 3 3 (0.3) (0.3) (0.3) (0.3) (0.3) (0.3)cobalt stearate *1 3 (0.3)sulfur 6 6 6 6 6 6 6accelerator *2 0.7 0.7 0.7 0.7 0.7 0.7 0.7meta-cresol resin *3 1 1 1 1 2 4 4hexamethoxy- 2 4 6 4 4 4 6methylmelamine *4hexamethylolmelaminepentamethyletherpartial condensate *5vulcanizationproperties(160° C. × 20 min)tensile strength 250 238 221 231 240 245 240breaking extension 390 345 305 340 355 365 340hardness (JIS A) 74 76 77.5 76.5 76.5 78 79initial adhesion(170° C. × 20 min)draw strength 97 100 97 99 100 99 98rubber coat (%) 95 95 95 95 95 95 95vulcanized warm waterresistant adhesion(170° C. × 20 min)draw strength 60 64 65 64 62 63 67rubber coat (%) 50 64 68 60 65 67 70separation test 110 100 90 90 90 85 85__________________________________________________________________________
TABLE 2______________________________________ Inventive Examples 1 2 3 4______________________________________natural rubber (RSS #1) 100 100 100 100carbon black (HAF) 60 60 60 60zinc oxide 10 10 10 10aging inhibitor 1 1 1 1(phenylenediamine)cobalt-naphthenate *1 3 3 3 3 (0.3) (0.3) (0.3) (0.3)cobalt stearate *1sulfur 6 6 6 6accelerator *2 0.7 0.7 0.7 0.7meta-cresol resin *3 1 1 2 4hexamethoxy-methylmelamine *4hexamethylolmelamine 2 4 4 6pentamethyletherpartial condensate *5vulcanizationproperties(160° C. × 20 min)tensile strength 255 246 250 255breaking extension 400 380 375 360hardness (JIS A) 77.5 79.5 81 83initial adhesion(170° C. × 20 min)draw strength 98 100 102 101rubber coat (%) 95 95 95 95vulcanized warm waterresistant adhesion(170° C. × 20 min)draw strength 73 78 80 79rubber coat (%) 78 82 86 85separation test 70 60 50 50______________________________________ Note: *1 each contains 10 weight % of cobalt element *2 N,Ndicyclohexylbenzothiazole sulfenamide *3 Sumicanol 610 (by Sumitomo Chemical Co., Ltd.) *4 Cyrez 964 (by American Cyanamid Co.) *5 Sumicanol 507 (containing 50% partial condensates of hexamethylolmelamine pentamethylether) | A rubber composition for steel-belted automobile tires containing selected amounts of partial condensates of hexamethylolmelamine pentamethylether, cresol resin, sulfur and cobalt salts of organic acid, to improve its warm water to steel cords in the tire and increased tensile strength. | 2 |
[0001] This application is a divisional application of co-pending U.S. application Ser. No. 10/446,328, filed May 27, 2003, entitled “Gas Supply Unit, Gas Supply Method And Exposure System”. Aforementioned, U.S. application Ser. No. 10/446,328, filed May 27, 2003, is incorporated by reference herein in its entirety.
[0002] This application claims the right of priority under 35 U.S.C. § 119 based on Japanese Patent Application No. 2002-153008, filed on May 27, 2002, which is hereby incorporated by reference herein in its entirety as if fully set forth herein.
BACKGROUND OF THE INVENTION
[0003] The present invention relates generally to gas supply units and methods for supplying inert gas to an exposure apparatus, and exposure systems using the same. In particular, the present invention is suitable for a gas supply unit, as well as to an exposure system, for supplying inert gas to an exposure light path of a projection exposure apparatus that uses far UV light and an excimer laser beam as a light source.
[0004] Along with recent demands on smaller and lower profile electronic devices, fine semiconductor devices to be mounted onto these electronic devices have been increasingly demanded. The conventional printing or photolithography for fabricating semiconductor devices has used a projection exposure apparatus.
[0005] In general, a projection exposure apparatus includes an illumination optical system that uses light emitted from a light source to illuminate a mask, and a projection optical system arranged between the mask and an object to be exposed. For a uniform illumination area, the illumination optical system introduces light from a light source into a light integrator, such as a fly-eye lens composed of multiple rod lenses, and uses a light exit plane of the light integrator as a secondary light source plane to Koehler-illuminate the mask plane through a condenser lens.
[0006] The minimum critical dimension to be transferred by the projection exposure apparatus (resolution) is proportionate to a wavelength of light used for exposure, and inversely proportionate to the numerical aperture of the projection optical system. The shorter the wavelength is, the better the resolution is.
[0007] Accordingly, the light source in recent years has been in transition from an ultra-high pressure mercury lamp (g-line with a wavelength of approximately 436 nm) and i-line with a wavelength of approximately 365 nm) to KrF excimer laser (with a wavelength of approximately 248 nm) and ArF excimer laser (with a wavelength of approximately 193 nm). Practical use of F 2 excimer laser (with a wavelength of 157 nm) has been promoted.
[0008] It is known that i-line or other exposure light with a shorter wavelength results in a photochemical reaction between the impurity in the air and oxygen (O 2 ) due to its short wavelength, which generates products to adhere to and opaque an optical element, such as a lens and a mirror in an optical system.
[0009] The products typically include ammonium sulfate ((NH 4 ) 2 SO 4 ), for example, which is produced by sulfuric acid (SO 2 ) that reacts with oxygen in the air or oxidizes when it absorbs light energy and gets excited. Ammonium sulfate is whitish and opaques an optical element, such as a lens and mirror, when it adheres to a surface of the optical element. Ammonium sulfate disperses and absorbs the exposure light, and lowers the transmittance of an optical system, thus greatly reducing an exposure light intensity or transmittance down to an object to be exposed and throughput.
[0010] The far UV light, such as excimer laser with a wavelength of 250 nm or less, particularly, ArF excimer laser having an oscillation wavelength of about 193 nm includes multiple oxygen absorption bands in this wavelength region. For example, as shown in FIG. 10 , inert gas supplied from a plant facility 1100 is supplied to a tube port 1210 in an exposure apparatus 1200 to purge its optical system and reduce oxygen concentration in the exposure light path to a very low level for exposure light with a less absorbent and purified oscillation wavelength. Here, FIG. 10 is a schematic block diagram of a conventional exposure apparatus.
[0011] It is also known that the F 2 excimer laser with an oscillation wavelength of about 157 nm includes consecutive oxygen absorption bands in this wavelength region, and does not allow exposure light with a less absorbent wavelength to be selected like the ArF excimer laser. The vacuum UV light with a wavelength of about 157 nm includes continuous steam absorption bands that cannot be observed around 193 nm. The vacuum UV light with 157 nm is easily absorbed by ammonia (NH 3 ), carbon dioxide (CO 2 ), organic gases, etc., and a light absorption in the exposure light path increases substantially, which is not a problem for the vacuum UV light with a wavelength of 160 nm or less.
[0012] A fluctuant concentration of a light absorbent material in the exposure light path during exposure would result in an error or discord of the actual exposure dose relative to the target exposure dose, and deteriorate the above throughput and an exposure-dose control precision.
[0013] Accordingly, the impurity concentration should be monitored in gas constituents in the exposure light path in a projection exposure apparatus that uses the far UV light or excimer laser for controls over optical systems in their product adhesion, efficiency and the exposure dose.
[0014] However, the conventional exposure apparatus shown in FIG. 10 cannot detect the impurity concentration of the supplied gas, and might cause the projection exposure apparatus to accept the inert gas, etc. with an impermissible impurity concentration due to malfunctions etc. of the plant facility. The inert gas, etc., with an impermissible impurity concentration supplied to the exposure apparatus would cause the following disadvantages:
[0015] (1) The light absorption increases in the exposure light path and considerably lowers the throughput of the apparatus. (2) The fluctuant light absorption in the exposure light path during an exposure operation causes a change or error in the actual exposure dose to the target exposure dose, and deteriorates the exposure-dose control accuracy. (3) Impurities in the inert gas, etc. in the exposure light path photochemically react and cause resultant products to adhere to an optical element, such as a lens and a mirror in an optical system. The products lower performance, such as the optical efficiency, and might require an exchange for an expensive optical element depending on adhesions. (4) The impurities adhere to a pipeline system for guiding the inert gas, etc. to the exposure light path, and might require its cleansing or exchange.
BRIEF SUMMARY OF THE INVENTION
[0016] Accordingly, it is an exemplary object of the present invention to provide a gas supply unit and method, and an exposure system having the same, which detect the inert gas with an impurity concentration beyond a permissible value, and prevent the inert gas from entering the exposure apparatus.
[0017] A gas supply unit of one aspect according to the present invention supplies gas to a certain space via a channel, and includes a first switch mechanism located in the channel for selectively changing the channel of the gas.
[0018] The gas supply unit may further include a first detector, provided in the channel, for detecting an impurity concentration in the gas, wherein the first switch mechanism is located downstream in the channel from the first detector in a direction supplying the gas, the first switch mechanism switching the channel of the gas when the first detector detects an impermissible impurity concentration.
[0019] The first switch mechanism switches the channel to a predetermined channel that has a filter for removing the impurity. The first switch mechanism may switch the channel to a predetermined channel connected to a reserve gas container that contains gas with a permissible impurity concentration. The gas supply unit may further include a first delay part, located between the first detector and the first changing mechanism, for delaying a flow of the gas.
[0020] The gas supply unit may further include a second detector for detecting an impurity concentration of the gas that has passed through the filter, and a shut-off valve, provided between the second detector and the certain space, which shuts off the gas, the shut-off valve shutting off the gas when the second detector detects that the impermissible impurity concentration. The gas supply unit may further includes a second switch mechanism, located downstream from the shut-off valve in a direction supplying the gas in the channel, for switching the channel, the switch mechanism selecting another channel that is connected to a unit for supplying the gas with a permissible impurity concentration, the second switch mechanism switching the channel to the different channel via when the shut-off valve shuts off the channel.
[0021] The gas supply unit may further include a controller for controlling operations of the first or second switch mechanism based on a detection result of the first or second detector. The impurity may include one or more of ammonia, carbon oxide, organic substances, inorganic substances, oxygen, and water. The gas supply unit may further include a second delay part, located between the second detector and the shut-off valve, for delaying a flow of the gas. The first or second delay part may be a delay tube or a tank. The gas supply unit may further include an exhaust part, located between the shut-off valve and the certain space, for exhausting the gas. The gas supply unit may further include an alarm that notifies of the impermissible impurity concentration of the gas. The gas supply unit may further include a power supply of uninterruptible power.
[0022] A gas supply method of another aspect of the present invention that detects an impurity concentration of a gas in a certain space, and switches a gas supply channel such that the certain space has a permissible impurity concentration of the gas includes the steps of storing information on a permissible value, comparing the permissible value stored in the storing step with a detected impurity concentration, and switching the supply channel based on a result of the comparing step. The gas supply method may include the step of stopping supplying the gas to the supply channel based on the result of the comparing step.
[0023] An exposure system of still another aspect includes the above gas supply unit, and an exposure apparatus that exposes an object by using ultraviolet light, far infrared light and vacuum ultraviolet light as exposure light, and the channel filled with the gas supplied by the gas supply unit.
[0024] A device fabrication method of still another aspect of the present invention includes the steps of exposing an object using the above exposure system, and performing a predetermined process for the projected and exposed object. Claims for a device fabrication method for performing operations similar to that of the above exposure apparatus cover devices as intermediate and final products. Such devices include semiconductor chips like an LSI and VLSI, CCDs, LCDs, magnetic sensors, thin film magnetic heads, and the like.
[0025] Other objects and further features of the present invention will become readily apparent from the following description of the preferred embodiments with reference to accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a schematic block diagram of an exposure system of a first embodiment according to the present invention.
[0027] FIG. 2 is a view showing an inert-gas flow introduced into the gas supply unit shown in FIG. 1 with a permissible inert-gas impurity concentration.
[0028] FIG. 3 is a view showing an inert-gas flow introduced into the gas supply unit shown in FIG. 1 with an impermissible inert-gas impurity concentration.
[0029] FIG. 4 is a view showing an inert-gas flow with impermissible impurity concentration that passes through a filter shown in FIG. 1 .
[0030] FIG. 5 is a view showing cleansing-gas and inert-gas flows when impurities are cleansed from the pipeline in the gas supply unit shown in FIG. 1 .
[0031] FIG. 6 is a schematic block diagram of a gas supply unit as a variation of the gas supply unit shown in FIG. 1 .
[0032] FIG. 7 is a schematic block diagram of an exposure system of a second embodiment according to the present invention.
[0033] FIG. 8 is a flowchart for a device fabrication method including an inventive exposure system.
[0034] FIG. 9 is a flowchart for a wafer process shown in FIG. 8 .
[0035] FIG. 10 is a schematic block diagram of a conventional exposure apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] A description will now be given of an exposure system as one embodiment according to the present invention with reference to accompanying drawings. However, the present invention is not limited to this embodiment, but each element may be replaced with an alternative element within the spirit and scope of the present invention. Here, FIG. 1 is a schematic block diagram of an exposure system 1 as a first embodiment of the present invention. As shown in FIG. 1 , the exposure system 1 includes a plant facility 100 , a gas supply unit 200 , a power supply 300 , an exhaust facility 400 , a spare gas supply unit 500 , and an exposure apparatus 700 . The exposure system 1 of the present embodiment is a system that supplies the exposure apparatus 700 with inert gas for exposure with an impurity concentration equal to or less than a permissible value from the plant facility 100 via the gas supply unit 200 .
[0037] Although the instant embodiment describes as if the gas supply unit, the spare gas supply unit, the exhaust facility, etc. are separate members from the exposure apparatus and the exposure system has all of them, the exposure apparatus may include the gas supply unit, the spare gas supply unit, the exhaust facility, etc. However, the factory facility 100 (for supplying inert gas and clean gas) is preferably a separate member from the exposure apparatus.
[0038] The plant facility 100 produces gas supplied to the exposure apparatus 700 via the gas supply unit 200 . The gas produced by the plant facility 100 is inert gas or clean dry air with a permissible concentration of impurities including ammonia (NH 3 ), carbon dioxide (CO 2 ), organic and inorganic matters, oxygen (O 2 ), and water (H 2 O). The instant embodiment separately forms the plant facility 100 that produces the inert gas and the gas supply unit 200 , but they may be integrated into one body so as to serve as the gas supply unit 200 , which will be described later.
[0039] The gas supply unit 200 detects an impurity concentration of gas produced from the plant facility 100 and supplies the exposure system 700 with the inert gas with a permissible impurity concentration. The gas supply unit 200 includes a port 210 , a first detector 220 , a delay tube 230 , a channel 240 , a second detector 250 , a delay tube 260 , a shut-off valve 270 , valves 280 and 282 , a controller 290 and an alarm 292 . Preferably, the delay tubes 230 and 260 at least partially have an S shape.
[0040] The port 210 is connected to the plant facility 100 , and separates the plant facility 100 and the gas supply unit 200 from each other. The port 210 introduces the inert gas produced by the plant facility 100 to the gas supply unit 200 .
[0041] The first detector 220 detects the concentration of one or more of ammonia, carbon dioxide, organic and inorganic substances, oxygen, and water as impurities contained in the inert gas introduced from the port 210 . The first detector 220 feeds a detected impurity-concentration result of the inert gas to the controller 290 . The first detector 220 may use a dry ammonia analyzer, a zirconia oxygen densitometer, a thin-film aluminum oxide moisture meter, etc.
[0042] The delay tube 230 is arranged between the first detector 220 and the channel 240 , which will be described later. The delay tube 230 is a first delay member that delays a flow of the inert gas with an impermissible impurity concentration (hereinafter called “contaminated inert gas”) until a supply channel for the inert gas is switched to the channel 240 so that the contaminated inert gas may not enter the exposure apparatus 700 .
[0043] The channel 240 includes a filter 242 , and valves 244 and 246 , and serves to remove the impurities of the contaminated gas. More specifically, when the first detector 220 detects that the gas supplied to the gas supply unit 200 from the plant facility 100 is the contaminated inert gas, the valve 244 switches the supply channel for the contaminated inert gas to the channel 240 and the filter 242 removes the impurity. The filter 242 may use a chemisorption refiner, and a porous substance, such as activated carbon and zeolite. The inert gas whose impurities are removed by the filter 242 returns to the original supply channel, and enters the second detector 250 . The controller 290 , which will be described later, switches the supply channel for the inert gas.
[0044] The second detector 250 detects a concentration of impurities, e.g., one or more of ammonia, carbon dioxide, organic and inorganic substances, oxygen, and water contained in the inert gas which have been removed by the filter 242 located in the channel 240 . The second detector 250 determines whether the filter 242 has removed the impurity of the contaminated inert gas and whether the impurity concentration becomes permissible. The second detector 250 feeds an impurity concentration result of the inert gas to the controller 290 . The controller 290 includes a microprocessor etc., determines whether the impurity concentration sent from the first and second detectors 220 and 250 is permissible or equal to or less than a predetermined value, and switches the valves if it is impermissible.
[0045] The delay tube 260 is arranged between the second detector 250 and the shut-off valve 270 , which will be described later. The delay tube 260 is a second delay member that delays a flow of the inert gas that has passed through the filter 242 located in the channel 240 and its impurity concentration exceeds the permissible value, or when the filter 242 does not remove impurity sufficiently until the shut-off valve 270 works to prevent the contaminated gas from entering the exposure apparatus 700 .
[0046] The shut-off valve 270 stops supplying the inert gas to the exposure apparatus 700 when the second detector 250 detects that the inert gas having passed through the channel 240 is contaminated.
[0047] The valve 280 switches channels for flowing cleansing gas to the exhaust the facility 400 when the impurity adheres to the pipeline system in the gas supply unit 200 , and the pipeline system needs to be cleaned.
[0048] The valve 282 switches connections so that the inert gas may be supplied to the exposure apparatus 700 from the spare gas supply unit 500 to allow the exposure apparatus 700 to continue actions while the impurity that sticks to the tube in the gas supply unit 200 is cleansed from the tube.
[0049] The controller 290 is connected to and controls the first detector 220 , the second detector 250 , the valves 244 , 246 , 280 , and 282 , and the shut-off 270 in the gas supply unit 200 . The controller 290 receives the impurity concentrations of the inert gas detected by the first and second detectors 220 and 250 , compares them with the permissible value, and, controls switching actions of the valves 244 , 246 , 280 and 282 , and the shut-off valve 270 based on these comparison results. The controller 290 has stored a permissible impurity-concentration value of the inert gas as a threshold in advance. A detailed description of its operations will be given later.
[0050] The alarm 292 informs via sounds, light, displays, etc. that the first and second detectors 220 and/or 250 have detected an impermissible impurity concentration of the inert gas. The alarm 292 can also inform of an operational status, such as cleaning and pipeline cleansing of the current gas supply unit 200 , and identify a supply channel for the inert gas.
[0051] The power supply 300 supplies all parts of the gas supply unit 200 with power. The power supply 300 is an uninterruptible one for privately generating electric power to prevent the gas supply unit 200 from stopping its actions due to a power failure, etc. during actions of the exposure system 1 and the contaminated inert gas from entering the exposure apparatus 700 by mistake.
[0052] The exhaust facility 400 exhausts cleansing gas via the valve 280 when the impurity adheres to the tube of the gas supply unit 200 , and the tube needs to be cleaned.
[0053] The spare gas supply unit (gas container) 500 supplies the exposure apparatus 700 with inert gas via the valve 282 in order to allow the exposure apparatus 700 to continue its actions even when the impurity has adhered to the tube and tube is being cleansed. The spare gas supply unit 500 may be of the same structure as that of the gas supply unit 200 , or it may be a unit that supplies the inert gas whose purity is assured in advance.
[0054] Referring to FIGS. 2-5 , a description will be given of the gas supply unit 200 's operation and a flow of inert gas that fills the exposure light path in the exposure apparatus 700 . Here, FIG. 2 is a view showing a flow of inert gas with a permissible impurity concentration, which has been introduced from the plant facility 100 to the gas supply unit 200 in a normal state. As illustrated, the flow of the inert gas is shown by an arrow.
[0055] Referring to FIG. 2 , the inert gas produced by the plant facility 100 is initially introduced to the port 210 of the gas supply unit 200 . The inert gas introduced to the port 210 enters the first detector 220 , which in turn detects its impurity concentration. The concentration detected by the first detector 220 is sent to the controller 290 , and compared with the permissible value. When the controller 290 determines that the inert gas has a permissible impurity concentration, it opens the valves 244 and 246 , the shut-off valve 270 , and the valves 280 and 282 . The delay tube 230 then delays a flow of the inert gas. Then, the inert gas is supplied to the exposure apparatus 700 through the valve 244 , the valve 246 , the second detector 250 , the delay tube 260 , the shut-off valve 270 , the valve 280 , and the valve 282 .
[0056] The second detector 250 in the present embodiment does not work since the inert gas has a permissible impurity concentration, but it may work when the impurity is likely to be mixed into the supply channel from the first detector 220 to the second detector 250 . In this case, the impurity concentration of the inert gas is sent to the controller 290 , which in turn closes the shut-off valve 270 to stop supplying the inert gas to the exposure apparatus 700 when determining that it exceeds the permissible value.
[0057] FIG. 3 is a view showing an inert-gas flow introduced from the plant facility 100 to the gas supply unit 220 when its impurity concentration exceeds the permissible value in an abnormal state. As illustrated, the flow of the inert gas is shown by an arrow.
[0058] Referring to FIG. 3 , at first, the inert gas produced by the plant facility 100 is introduced to the port 210 of the gas supply unit 200 . The inert gas introduced to the port 210 enters the first detector 220 , which in turn detects its impurity concentration. The concentration detected by the first detector 220 is sent to the controller 290 , and compared with the permissible value. When the controller 290 determines that the impurity concentration of the inert gas exceeds the permissible value, it switches the valves 244 and 246 to supply the contaminated inert gas to the channel 240 , and prevent the contaminated inert gas from flowing downstream. The controller 290 uses the alarm 292 to notify an operator via sounds, light, displays, etc., that the inert gas has an impermissible impurity concentration, and switches the valves 244 and 246 . The delay tube 230 delays a flow of the inert gas during this period, and the contaminated inert gas never enters the second detector 250 through the valves 244 and 246 . The filter 242 removes the impurity from the contaminated inert gas in the channel 240 . The inert gas whose impurity has been removed by the filter 242 enters the second detector 250 via the valve 246 , which in turn detects a concentration of its impurities. The impurity concentration detected by the second detector 250 is sent the controller 290 , and compared with the permissible value. When the controller 290 determines that the inert gas has a permissible impurity concentration, it opens the shut-off valve 270 and the valves 280 and 282 . The delay tube 260 delays a flow of the inert gas during this period. The inert gas is then supplied to the exposure apparatus 700 through the shut-off valve 270 and the valves 280 and 282 .
[0059] When the controller 290 determines that the inert gas that has passed through the filter 242 of the channel 240 has an impermissible impurity concentration, it closes the shut-off valve 270 and stops supplying the inert gas to the exposure apparatus 700 , as shown in FIG. 4 . The controller 290 uses the alarm 292 to notify an operator via sounds, light, displays, etc. that the inert gas has an impermissible impurity concentration, as well as switching the valves 244 and 246 . The delay tube 260 delays a flow of the inert gas this time, and the contaminated inert gas never enters the exposure apparatus 700 through the valves 280 and 282 . Here, FIG. 4 is a view showing an inert-gas flow with impermissible impurity concentration in an abnormal state that passes through the filter 250 in the channel 240 . As illustrated, the flow of the inert gas is shown by an arrow.
[0060] FIG. 5 is a view showing cleansing-gas and inert-gas flows when the impurity is cleansed from the pipeline in the gas supply unit 200 when the impurity concentration of the inert gas introduced from the plant facility 100 to the gas supply unit 200 exceeds the permissible value. As illustrated, the flow of the cleansing gas and inert gas is shown by an arrow.
[0061] A cleansing gas supply unit 600 introduces a cleansing gas to the gas supply unit 200 via the port 210 . The cleansing gas removes the impurity adhering to the pipeline system in the gas supply unit 200 . The cleansing gas uses inert gas of nitrogen, etc. with a confirmedly permissible impurity concentration. Referring to FIG. 5 , the valve 282 is switched such that inert gas is supplied to the exposure apparatus 700 from the spare gas supply unit 500 that has the inert gas with a confirmedly permissible impurity concentration. Thus, the exposure apparatus 700 may act even when the pipeline of the gas supply unit 200 is being cleaned. The port 210 is disconnected between the plant facility 100 and the gas supply unit 200 , and connected to the cleansing gas supply unit 600 . Then, the valve 280 is switched to connect the flow channel for the cleansing gas to the exhaust facility 400 .
[0062] The cleansing gas is introduced from the cleansing gas supply unit 600 to the port 210 in the gas supply unit 200 . The cleansing gas introduced to the port 210 is exhausted to the exhaust facility 400 through the first detector 220 , the delay tube 230 , the valves 244 and 246 , the second detector 250 , the delay tube 260 , the shut-off valve 270 and the valve 280 . The cleansing gas then removes the impurity that clings to the pipeline in the gas supply unit 200 .
[0063] Upon completion of removal of the impurity adhering to the pipeline in the gas supply unit 200 , the port 210 is disconnected from the cleansing gas supply unit 600 and connected to the plant facility 100 , which has the inert gas with a confirmedly permissible impurity concentration. The inert gas is introduced from the plant facility 100 to the gas supply unit 200 , and exhausted from the exhaust facility 400 . The first and second detectors 220 and 250 detect the impurity concentration of the inert gas. The concentrations detected by the first and second detectors 220 and 250 are sent to the controller 290 for comparison with the permissible value. When the inert gas has a confirmedly permissible impurity concentration, the valves 280 and 282 are switched such that the inert gas from the plant facility 100 is supplied to the exposure apparatus 700 . When the impurity concentration of the inert gas exceeds the permissible value, the plant facility 100 and the port 210 are disconnected, and instead, the cleansing gas supply unit 600 is connected to repeat the cleaning of the gas supply unit 200 's pipeline by using the cleansing gas.
[0064] Referring now to FIG. 6 , a description will be given of a gas supply unit 200 A as a variation of the gas supply unit 200 . The gas supply unit 200 A differs from the gas supply unit 200 in the delay tubes 230 and 260 as the first and second delay parts. Here, FIG. 6 is a schematic block diagram of a gas supply unit 200 A as a variation of the gas supply unit 200 shown in FIG. 1 .
[0065] Similar to the gas supply 200 , the gas supply unit 200 A detects an impurity concentration of the inert gas produced by the plant facility 100 and supplies to the exposure apparatus 700 the inert gas with a permissible impurity concentration.
[0066] A delay tank 230 A is arranged between the first detector 220 and the channel 240 , and serves as a first delay member that delays a flow of the inert gas with an impermissible impurity concentration until the supply channel for the inert gas is switched to the channel 240 so that the contaminated inert gas may not enter the exposure apparatus 700 .
[0067] A delay tank 260 A is arranged between the second detector 250 and the shut-off valve 270 , and serves as a second delay member that delays a flow of the inert gas that has passed through the filter 242 of the channel 240 and includes an impermissible impurity concentration or when the filter 242 does not remove the impurity sufficiently until the shut-off valve 270 works, so that the contaminated inert gas may not enter the exposure apparatus 700 .
[0068] The gas supply unit 200 A's action and the flow of the inert gas filling the exposure light path in the exposure apparatus 700 are the same as those of the gas supply unit 200 , and a description thereof will be omitted.
[0069] Turning back to FIG. 1 again, the exposure apparatus 700 includes an illumination apparatus 710 that illuminates a mask or reticle (these terms are used interchangeably in the present application) 720 which forms a pattern, a stage 745 that supports a plate, and a projection optical system 730 that projects diffracted light arising from the illuminated mask pattern to the plate 740 , and a piping unit 750 .
[0070] The exposure apparatus 700 is a projection exposure apparatus that exposes a circuit pattern formed on the mask 720 onto the plate 740 , e.g., in a step-and-repeat or step-and-scan manner. Such an exposure apparatus is suitable for a photolithography process of a sub-micron or a quarter-micron or less. A description will be given below of a step-and-scan exposure apparatus (which is also referred to as a “scanner”) as an example. The “step-and-scan” manner, as used herein, is one mode of exposure method which exposes a pattern on a mask onto a wafer by continuously scanning the wafer relative to the mask, and by moving, after a shot of exposure, the wafer stepwise to the next exposure area to be shot. The “step-and-repeat” manner is another mode of exposure method which moves a wafer stepwise to an exposure area for the next shot every shot onto the wafer.
[0071] The illumination apparatus 710 illuminates the mask 720 which forms a circuit pattern to be transferred, and includes a light source section 712 , a delivery optics unit 714 , and an illumination optical system 716 .
[0072] The light source section 712 employs, e.g., laser as a light source. The laser may use ArF excimer laser with a wavelength of approximately about 193 nm, KrF excimer laser with a wavelength of about 248 nm, F 2 excimer laser with a wavelength of about 153 nm, etc. However, a kind of laser is not limited to excimer laser. For example, YAG laser can be used, and the number of laser units is not limited. For example, if two units of solid laser that operates independently are used, no coherence between these solid laser units exists, and thus, speckles arising from the coherence will be reduced considerably. In order to reduce speckles, it would be preferable to oscillate an optical system in a straight or rotating manner. When the light source section 712 uses laser, it is desirable to employ a beam shaping optical system that shapes a parallel beam from a laser source to a desired beam shape, and an incoherently turning optical system that turns a coherent laser beam into an incoherent one. A light source applicable to the light source part 712 is not limited to the laser, but may use one or more lamps such as a mercury lamp, xenon lamp, etc.
[0073] The delivery optics unit 714 guides light from the light source section 712 to the illumination optical system 716 . The illumination optical system 716 is an optical system that illuminates the mask 729 , including a lens, a mirror, a light integrator, a stop, and the like, for example, in the order of a condenser lens, a fly-eye lens, an aperture stop, a condenser lens, a slit, and an imaging optical system. The illumination optical system 716 can use any light whether it is axial or non-axial light. The light integrator may include a fly-eye lens or an integrator formed by stacking two sets of cylindrical lens array plates (or lenticular lenses), and be replaced with an optical rod or a diffractive element.
[0074] The mask 720 forms a circuit pattern or an image to be transferred, and is made, for example, of quartz and supported and driven by a mask stage (not shown). Diffracted light through the mask 720 is projected onto the plate 740 through the projection optical system 730 . The plate 740 is an object to be exposed such as a wafer or a liquid crystal plate, onto which resist is applied. The mask 720 and plate 740 are located in a conjugate relationship. When the exposure apparatus 700 is a scanner, it transfers a pattern on the mask 720 onto the plate 740 by scanning the mask 720 and plate 740 . When the exposure apparatus 700 is a stepper (or a “step-and-repeat” exposure apparatus), it exposes while resting the mask 720 and plate 740 .
[0075] The projection optical system 730 may use an optical system including plural lens elements, an optical system including plural lens elements and at least one concave mirror (a catadioptric optical system), an optical system including plural lens elements and at least one diffractive optical element such as a kinoform, a full mirror type optical system, and so on. Any necessary correction of the chromatic aberration may use plural lens units made from glass materials having different dispersion values (Abbe values), or arrange a diffractive optical element such that it disperses in a direction opposite to that of the lens unit.
[0076] Photoresist is applied onto the plate 740 . A photoresist application step includes a pretreatment, an adhesion accelerator application treatment, a photo-resist application treatment, and a pre-bake treatment. The pretreatment includes cleaning, drying, etc. The adhesion accelerator application treatment is a surface reforming process so as to enhance the adhesion between the photo resist and a base (i.e., a process to increase the hydrophobicity by applying a surface active agent), through a coat or vaporous process using an organic film such as HMDS (Hexamethyl-disilazane). The pre-bake treatment is a baking (or burning) step, softer than that after development, which removes the solvent.
[0077] The stage 745 supports the plate 740 . The stage 745 may use any structure known in the art, and thus a detailed description of its structure and operations is omitted. For example, the stage 745 may use a linear motor to move the plate 740 in directions X and Y. The mask 720 and plate 740 are, for example, scanned synchronously, and the positions of the stage 745 and mask stage (not shown) are monitored, for example, by a laser interferometer and the like, so that both are driven at a constant speed ratio. The stage 745 is installed on a stage stool supported on the floor and the like, for example, via a damper, and the mask stage and the projection optical system 730 are installed on a lens barrel stool (not shown) supported, for example, via a damper on a base-frame placed on the floor and the like.
[0078] The piping unit 750 has a pipeline port 752 , and supplies the inert gas into the exposure light path while decompressing its pressure and adjusting its flow rate, the inert gas that is supplied with a permissible impurity concentration from the gas supply unit 200 connected via the pipeline port 752 . The pipeline unit 750 allows the exposure light path to be filled with the inert gas with a permissible impurity concentration. This may prevent extremely lowered throughput due to augmented light absorption in the exposure light path caused by impurity of the inert gas, the degraded exposure-dose control accuracy due to the fluctuant light absorption in the exposure light path during exposure and fluctuant or erroneous exposure dose, and lowered performance such as optical efficiency as a result of adhesions of impurity onto an optical element, such as a lens and a mirror in an optical system and its photochemical reactions in the exposure light path and product generated by the reactions.
[0079] In exposure, light emitted from the light source section 712 uses the illumination optical system 716 to Koehler-illuminate the mask 720 . Light passing the mask 720 and reflecting the mask pattern is imaged onto the plate 740 by the projection optical system 730 . Since the inside of the exposure apparatus 700 's exposure light path is filled with the inert gas supplied with a permissible impurity concentration by the inventive gas supply unit 200 , UV, far UV light and vacuum UV light are transmitted with high transmittance, and may provide devices (such as semiconductor devices, LCD devices, image pick-up devices (such as CCDs), thin-film magnetic heads, etc. with high throughput and high economical efficiency.
[0080] Referring now to FIG. 7 , a description will be given of an exposure system 2 of a second embodiment according to the present invention. FIG. 7 is a schematic block diagram of the exposure system 2 of the second embodiment according to the present invention. The exposure system 2 in FIG. 7 is similar to the exposure system 1 in FIG. 1 , but differs in the structure of the gas supply unit 200 . Incidentally, for the same elements as are shown in the exposure system 1 in FIG. 1 , the same reference numerals are assigned such that a duplicate description of them is avoided.
[0081] As shown in FIG. 7 , the exposure system 2 includes the plant facility 100 , a gas supply unit 800 , an electric power supply 300 , the exhaust facility 400 , the spare gas supply unit 500 , and the exposure apparatus 700 . The exposure system 2 of this embodiment is a system that uses the gas supply unit 800 to supply the exposure apparatus 700 with the inert gas with a permissible impurity concentration from the plant facility 100 for exposure.
[0082] The gas supply unit 800 supplies the exposure apparatus 700 with the inert gas with a permissible impurity concentration and detects the impurity concentration of the inert gas produced by the plant facility 100 . As illustrated, the gas supply unit 800 has a gas container 812 in place of the filter 242 and the valves 244 and 246 , the shut-off valve 814 , and the valve 816 in the channel 810 .
[0083] The channel 810 includes the gas container 812 , the shut-off valve 814 and valve 816 . The channel 810 is to provide the exposure apparatus 700 with the inert gas from the gas container 812 that is filled with the apparently purified inert gas, when the first detector 220 has detected that the inert gas supplied from the plant facility 100 to the gas supply unit 800 is contaminated inert gas. The shut-off valve 814 opens and closes the gas container 812 . The valve 816 switches a supply channel of the inert gas to the channel 810 . The controller 290 controls switching of the supply channel of the inert gas or the opening/closing of the shut-off valve 814 and the switching of the valve 816 .
[0084] A description will be given of the operations of the gas supply unit 800 and a flow of the inert gas filling the exposure light path in the exposure apparatus 800 . FIG. 7 indicates the flow of the inert gas by an arrow.
[0085] At first, the inert gas produced by the plant facility 100 is introduced to the port 210 of the gas supply unit 800 . The inert gas introduced to the port 210 enters the first detector 220 , which in turn detects its impurity concentration. The concentration detected by the first detector 220 is sent to the controller 290 , and compared with the permissible value.
[0086] If the controller 290 determines that the inert gas has a permissible impurity concentration, it controls the valve 816 to switch the channel supplying the inert gas to the channel 810 , and prevents the contaminated inert gas from flowing downstream. The controller 290 notifies an operator through sounds, light, displays, etc. of an impermissible impurity concentration of the inert gas via the alarm 292 . The delay tube 230 delays a flow of the inert gas this time, and the contaminated inert gas never enters the valve 816 and the second detector 250 . The controller 290 then opens the shut-off valve 814 , which allows the inert gas to flow from the gas container 812 via the valve 816 into the second detector 250 , which in turn detects the impurity concentration. The impurity concentration detected by the second detector 250 is sent to the controller 290 , and compared with the permissible value. When the controller 290 determines that the inert gas has a permissible impurity concentration, it opens the shut-off valve 270 , and the valves 280 and 282 . The delay tube 260 delays a flow of the inert gas during this time. Then, the inert gas is supplied to the exposure apparatus 700 through the shut-off valve 270 , and the valves 280 and 282 .
[0087] When the controller 290 determines that the inert gas that is supplied from the gas container 812 in the channel 810 and has an impermissible impurity concentration, it closes the shut-off valve 270 and stops supplying the inert gas to the exposure apparatus 700 . The controller 290 closes the shut-off valve 270 and notifies an operator through sounds, light, displays, etc. from the alarm 292 that the inert gas has an impermissible impurity concentration. The delay tube 260 delays a flow of the inert gas during this time, and the contaminated inert gas never enters the valves 280 and 282 and flows into the exposure 700 .
[0088] Referring now to FIGS. 8 and 9 , a description will be given of an embodiment of a device fabricating method using the above exposure apparatus 1 . FIG. 8 is a flowchart for explaining a fabrication of devices (i.e., semiconductor chips such as IC and LSI, LCDs, CCDs, etc.). Here, a description will be given of a fabrication of a semiconductor chip as an example. Step 1 (circuit design) designs a semiconductor device circuit. Step 2 (mask fabrication) forms a mask having a designed circuit pattern. Step 3 (wafer preparation) manufactures a wafer using materials such as silicon. Step 4 (wafer process), which is referred to as a pretreatment, forms actual circuitry on the wafer through photolithography using the mask and wafer. Step 5 (assembly), which is also referred to as a posttreatment, forms into a semiconductor chip the wafer formed in Step 4 and includes an assembly step (e.g., dicing, bonding), a packaging step (chip sealing), and the like. Step 6 (inspection) performs various tests for the semiconductor device made in Step 5 , such as a validity test and a durability test. Through these steps, a semiconductor device is finished and shipped (Step 7 ).
[0089] FIG. 9 is a detailed flowchart of the wafer process in Step 4 . Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer's surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor disposition and the like. Step 14 (ion implantation) implants ion into the wafer. Step 15 (resist process) applies a photosensitive material onto the wafer. Step 16 (exposure) uses the exposure apparatus 200 to expose a circuit pattern on the mask onto the wafer. Step 17 (development) develops the exposed wafer. Step 18 (etching) etches parts other than a developed resist image. Step 19 (resist stripping) removes disused resist after etching. These steps are repeated, and multilayer circuit patterns are formed on the wafer. The device fabrication method of this embodiment may manufacture higher quality devices than the conventional one.
[0090] The above gas supply unit and method, and exposure systems may detect the inert gas with an impermissible impurity concentration, and prevent that inert gas from entering an exposure apparatus. This may prevent extremely lowered throughput due to augmented light absorption in the exposure light path caused by impurity of the inert gas, the degraded exposure-dose control accuracy due to the fluctuant light absorption in the exposure light path during exposure and fluctuant or erroneous exposure dose, and lowered performance such as optical efficiency as a result of adhesions of impurity onto an optical element, such as a lens and a mirror in an optical system and its photochemical reactions in the exposure light path and product generated by the reactions. This may also reduce cost incurred in exchanging optical elements and pipelines to which the impurities have adhered.
[0091] Only when an impurity concentration of supplied inert gas exceeds a permissible value, a filter removes the impurity or a gas container of the inert gas works with the purified inert gas. Thus, a regular exchange of the filter or gas container is unnecessary, restraining the running cost.
[0092] Further, the present invention is not limited to these preferred embodiments, and various variations and modifications may be made without departing from the scope of the present invention.
[0093] The gas supply unit, the supply method, and the exposure system of the instant invention can detect the inert gas with an impermissible impurity concentration, and prevent that inert gas from entering the exposure apparatus. | A gas supply unit supplies gas to a certain space via a channel, and includes a first switch mechanism located in the channel for selectively changing the channel of the gas. | 5 |
RELATED CASES
[0001] This application is based on and claims priority to U.S. Provisional Patent Application No. 60/402,878, filed Aug. 8, 2002, the entire contents of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention is directed to nitrogen generators, and in particular, portable cryogenic nitrogen generators.
[0004] 2. Description of the Related Art
[0005] Inert gases are widely used in many industrial processes. For example, nitrogen gas is commonly used in conjunction with operation of a drilling rig for oil, gas, or geothermal wells, as well as for post drilling operations. In particular, nitrogen is injected into the down-hole region during a drilling operation, to remove drill cuttings.
[0006] In the art of well drilling, tubular casings are typically inserted into the wells so as to secure the perimeter of the wellbore. In some wells, multiple casings are secured at the surface of the well to lower down-hole locations. Other types of casings, called liners, are sometimes used to extend from the lower-most casing into the lower-most portion of the wellbore. Drilling fluids, such as drilling mud, are often used when large flows of water are present in the well. The drilling mud is circulated down the drill string, through the drill bit, and up the annular region between the drill string and the wellbore or casing. Gas, such as Nitrogen gas, may be injected into the down-hole region to provide faster drilling when substantial amounts of water are not present in the well.
[0007] In the past, air has been used as the principal down-hole drilling fluid for lower water content drilling. The air can be combined with a surfactant, foaming agent, water, and/or mud for different applications. The primary advantages of straight air drilling are greatly increased penetration rates, greater bit footage, and fewer down-hole drilling problems.
[0008] However, drilling with air does raise a number of disadvantages. For example, injection of high-pressure air into a down-hole during a drilling operation increases corrosion rates and raises the risk of explosions or fire due to the presence of high levels of oxygen in the pressurized air. In order to reduce the risk of explosions or fire, it has been known to reduce the temperature of the injected air, or to replace the air with an inert gas, such as Nitrogen.
[0009] One option for supplying nitrogen gas to the down-hole region of a well during a drilling operation is to ship containerized nitrogen to the drilling site and pump the nitrogen gas into the well at a pressure from about 200 psig to 10,000 psig. However, the shipment of containerized nitrogen to a drilling site, which may be in a remote location, can be expensive. Thus, it is more desirable to generate nitrogen gas at the site of the drilling operation.
[0010] One option for producing nitrogen gas at a drilling site is disclosed in U.S. Pat. No. 6,041,873 issued to Michael, the entire contents of which is hereby expressly incorporated by reference. The Michael patent discloses a portable unit that produces nitrogen gas through non-cryogenic systems including membrane separation units.
SUMMARY OF THE INVENTION
[0011] One drawback of non-cryogenic devices is that efficiency drops off rapidly as purity increases. For example, it has been found that portable membrane separation units can provide 95% pure nitrogen gas at a flow rate sufficient for drilling operations. However, these units are not practical for generating an appropriate nitrogen flow at purities of above 95%, and in particular, purities above 99.0%.
[0012] One aspect of the present invention includes the realization that cryogenic nitrogen generators can be made sufficiently portable to provide practicable sources of higher purity nitrogen gas for drilling operations.
[0013] Another aspect of the present invention includes the realization that standard sized containers can be used to provide a protective housing during transportation and operation of the cryogenic nitrogen generator. By using standard size containers to form a housing for a cryogenic nitrogen generator, such as a cryogenic distillation and associated heat exchanger unit, the device can be shipped to a drilling site and efficiently and quickly assembled into an operative state. For example, a cryogenic nitrogen generator can include an air preparation unit and a cryogenic distillation and associated heat exchanger unit. The air preparation unit typically will include an absorption device, such as a Pressure Swing Absorption (PSA) or a Temperature Swing Absorption (TSA) unit. Optionally, the air preparation unit can also include one or a plurality of air compressor units. The air preparation unit can be configured to fit within a standard ISO container resting horizontally. However, a cryogenic distillation unit is quite tall. For example, typical cryogenic distillation units, also known as “cold boxes,” can be as tall as 30 feet or more to produce Nitrogen gas of better than 99% purity. Thus, the distillation unit can be separately housed in a standard ISO container. With these units separately housed as such, they can be transported to and through virtually any country in the world using standard sized trucks or via ocean-going ships. Additionally, once delivered to a drilling site, the separate components can be connected and operated while they remain in the separate containers.
[0014] A further advantage in using ISO containers is that such containers include standard anchoring points which can be connected together. For example, anchoring points of each container can be connected together so as to provide further stability for plumbing connections between the containers and also to provide further stability to the container housing the distillation unit. For example, because the distillation unit is tall, connection to another container, and in particular another ISO container, provides further stability to the total system.
[0015] Typical cryogenic air separation plants are designed to remove normal levels of carbon dioxide, hydrocarbons, sulfur containing compounds, and other acid gases in ambient feed air. However, ambient air contaminate levels at oil or gas exploration drilling and recovery sites can be higher than normal levels, making it necessary to use additional precautions to ensure safe air separation plant operation. Accordingly, in one embodiment, the air preparation unit also includes a catalytic converter to remove hydrocarbons from an ambient air stream, preferably before the air stream enters the absorption device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] [0016]FIG. 1 is a schematic illustration of a gas separation unit constructed in accordance with one aspect of the present invention;
[0017] [0017]FIG. 2 is a schematic illustration of a modification of the gas separation unit illustrated in FIG. 1;
[0018] [0018]FIG. 3 is a schematic illustration of the gas separation unit illustrated in FIG. 1 containing a catalytic reactor system.
[0019] [0019]FIG. 4 is a front, top, and left side perspective view of a housing assembly for the gas separation units illustrated in FIGS. 1 and 2, the housing assembly including a generally horizontal portion and a generally vertical portion;
[0020] [0020]FIG. 4A is a left side elevational view of the generally vertical portion of the housing assembly of FIG. 4;
[0021] [0021]FIG. 5 is a front, top, and left side perspective view of the housing unit illustrated in FIG. 4, with components of the gas separation units illustrated in FIGS. 1 and 2 shown in phantom;
[0022] [0022]FIG. 6 is a front, top, and left side perspective view of a modification of the housing assembly illustrated in FIG. 5;
[0023] [0023]FIG. 6A is a rear elevational view of the horizontal portion of the housing assembly shown in FIG. 6; and
[0024] [0024]FIG. 7 is a front, top, and left side perspective view of a further modification of the housing assembly illustrated in FIG. 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0025] With reference to FIG. 1, a gas separation unit, constructed in accordance with one aspect of the present invention, is illustrated therein identified by the reference numeral 10 . The gas separation unit 10 comprises an air source 12 , an absorption unit 14 , and a cryogenic distillation unit 16 .
[0026] The air source 12 can be in the form of any source of air. Preferably, the air source 12 is an air compressor configured to pressurize air. Any commercially available air compressor can be used for the air source 12 . For example, the air source 12 can be a centrifugal, dry or lubricated screw, or reciprocating-type air compressor. If an oil-lubricated system is used, additional equipment can be used to remove oil droplets and vapors formed during the compression process.
[0027] The absorption unit 14 can be in the form of a pressure swing absorption (PSA) or a temperature swing absorption (TSA) system. Preferably, the absorption unit 14 is configured to remove water vapor, carbon dioxide, and other air contaminants from a feed stream of air from the air source 12 . The illustrated absorption unit 14 is a pressure swing absorption unit and preferably includes at least two absorption beds 18 , 20 . In the illustrated embodiment, the absorption unit 14 includes three absorption beds, 18 , 20 , and 22 . The absorption unit 14 also includes a set of check valves 23 disposed downstream of the absorption beds 18 , 20 , 22 to prevent reverse flow into the absorption beds 18 , 20 , 22 during operation of the unit 14 and to allow flow into the beds 18 , 20 , 22 to reactivate the beds 18 , 20 , 22 by purging, described below. Those of ordinary skill in the art readily appreciate that the check valves can be in the form of passive mechanical check valves, or electronically controlled solenoid or switch controlled valves.
[0028] The absorption unit 14 also includes the controller 24 . The controller 24 can be in the form of a programmable logic controller configured to emit electronic control signals via a plurality of connectors 25 to a plurality of electronic actuators 27 which control the operation of a plurality of valves 29 which, in turn, control the flow of gases in and out of the beds 18 , 20 , 22 . Alternatively, the controller 24 can be configured to selectively apply pneumatic pressure to a plurality of pneumatic actuators for controlling the valves 29 . The operation of the controller 24 and the associated valves 29 is well known in the art and thus will not be described further.
[0029] The cryogenic distillation unit 16 includes a main heat exchanger 26 , a distillation column 28 , and preferably a sub-cooler 30 . The illustrated embodiment also includes a coolant reservoir 32 , a purge vaporizer 33 , and a defrosting circuit 34 . The operation of the defrosting circuit 34 is well known in the art, and thus is not described further.
[0030] In operation, compressed air is delivered from the air source 12 to the absorption unit 14 through a compressed air conduit 36 . A condensate trap 37 is disposed inline with the conduit 36 . The trap 37 removes condensed water and oil from the air supplied by the air source 12 before it enters the absorption unit 14 . In the absorption unit 14 , water vapor, carbon dioxide, and a majority of other air contaminants are removed. As noted above, the illustrated absorption unit is a pressure swing absorption device.
[0031] In the illustrated embodiment, the absorption unit can be configured to provide pre-purification of the compressed air from the air source 12 . As known in the art, the absorption unit 14 , operating under a pressure swing absorption principle, selectively pressurizes and depressurizes the beds 18 , 20 , 22 through the actuation of the valves 29 which are controlled by the controller 24 . Absorbent material in the beds 18 , 20 , 22 is used to absorb the water vapor, carbon dioxide, and other air contaminants. Once each bed is saturated with the waste products, the bed can be reactivated by purging, described below. The pre-purified air from the absorption unit 14 can be delivered to the cryogenic distillation unit 16 through a conduit 38 . Check valves 23 disposed downstream of the absorption beds 18 , 20 , 22 can prevent reverse flow along the conduit 38 during operation of the absorption unit 14 . A particulate filter 39 can be disposed in-line with the conduit 38 . The particulate filter 39 prevents dust from the absorption unit 14 from entering the cryogenic distillation unit 16 .
[0032] The pre-purified and compressed air, which is predominately oxygen and nitrogen, is fed into the main heat exchanger 26 . The main heat exchanger 26 is configured to cool the incoming pre-purified air to its condensing temperature. Refrigeration for cooling the incoming pre-purified air is provided by purified nitrogen (i.e., product nitrogen) and waste gas discharged from the distillation unit 16 , described in greater detail below. A startup/defrost loop control 41 connects to the conduit 38 upstream of the heat exchanger 26 . The loop control 41 diverts a portion of the air stream through the defrosting circuit 34 and associated valves 43 during the initial activation of the absorption unit 14 and for periodic defrosting of the cryogenic distillation unit 16 to remove built-up contaminates. An instrument air supply line 45 can also be connected to the conduit 38 upstream of the heat exchanger 26 and diverts a portion of the pre-purified air stream to supply instrument air to plant controls and instruments.
[0033] The cooled pre-purified air discharged from the main heat exchanger 26 is supplied to the distillation column 28 through a conduit 40 . A safety valve 47 can be connected to the conduit 40 to provide high-pressure safety relief to the heat exchanger 26 and distillation column 28 . The conduit 40 is connected to a lower end of the distillation column 28 . As the cooled and pre-purified air enters the distillation column 28 , it contacts a descending liquid reflux, described in greater detail below.
[0034] As the pre-purified and cooled air rises within the distillation column 28 , the nitrogen concentration increases until it reaches the top of the column. Preferably, the pre-purified and cooled air rises through a series of distillation trays or packing material as it rises through the distillation column 28 .
[0035] Above the distillation trays or packing material, a further heat exchanger, commonly known as a “condenser/reboiler,” can be disposed within the distillation column. The rising pre-purified and cooled air, which has been distilled into purified or “product nitrogen,” rises and thus flows into thermal communication with the reboiler/condenser where it is condensed against a boiling stream of oxygen-enriched reflux, described in greater detail below.
[0036] The condensed liquid nitrogen then falls into the distillation column, and in particular through the distillation trays or packing material, and thus effects the desired separation on the rising pre-purified gas. As noted above, the falling condensed nitrogen is referred to as “liquid reflux.” As this liquid reflux falls through the distillation column, it causes oxygen to separate out of the rising pre-purified air and thus the liquid reflux itself becomes enriched with oxygen.
[0037] At the bottom of the distillation column, the liquid reflux stream, which includes liquid nitrogen enriched with oxygen, pools. The pooled liquid reflux is discharged from the lower end of the distillation column through a conduit 42 . The liquid reflux, flowing through the conduit 42 , enters an optional subcooler 30 . After leaving the subcooler 30 , the liquid reflux flows through the pressure reduction valve 44 , which lowers pressure and thus lowers the boiling point of the liquid reflux to a temperature lower than the boiling point of the higher pressure nitrogen gas flowing upward toward the top of the distillation column 28 . Thus, as the liquid reflux boils, and thus changes phase, it absorbs heat from the higher-pressure nitrogen gas flowing up towards the top of the distillation column 28 .
[0038] Optionally, a portion of the liquid reflux is diverted to the purge vaporizer 33 to prevent the build up of contaminates. In one embodiment, the vaporizer 33 comprises an external heat exchanger that vaporizes the liquid against compressed air. In another alternative, a portion of the liquid reflux can be mixed with waste stream entering the cold end of the vaporizer.
[0039] In order to compensate for process and heat leak refrigeration losses, liquid nitrogen (LIN) from the liquid coolant reservoir 32 is introduced at the top of the distillation column where it is mixed with the reflux stream of oxygen enriched liquid nitrogen flowing downward through the distillation column 28 and is thus used in the distillation process to further aid and separation of oxygen from the rising pre-purified air. A liquid assist control valve 49 is disposed downstream of the reservoir 32 and regulates the flow of liquid nitrogen from the reservoir 32 into the distillation column 28 .
[0040] The uncondensed gaseous nitrogen at the top of the distillation column is directed to the cold end of the main heat exchanger 26 through a conduit 46 . As the uncondensed nitrogen gas passes through the main heat exchanger 26 , it absorbs heat from the incoming pre-purified air, as noted above. As the flow of uncondensed nitrogen gas leaves the main heat exchanger 26 , it is approximately at ambient temperature. This flow of product nitrogen gas at ambient temperature is delivered to either a generator battery limits or to the suction of a booster compressor where it is raised to the desired delivery pressure. For a drilling operation, the pressure can be raised to from about 70 psig to about 10,000 psig. More typically, the pressure is raised from about 1,000 to 2,000 psig.
[0041] With reference again to the reboiler/condenser and the distillation column 28 , as the liquid reflux is revaporized, it is discharged from the top of the distillation column 28 through a conduit 48 . The conduit 48 directs the vaporized oxygen enriched reflux through the optional subcooler 30 . In the subcooler 30 , heat from the liquid reflux flowing through the conduit 42 is absorbed by the flow of vaporized reflux flowing through the conduit 48 . After the subcooler, the vaporized reflux is directed through the cold end of the main heat exchanger 26 .
[0042] Within the main heat exchanger 26 , the vaporized reflux absorbs additional heat from the incoming flow of pre-purified air. The vaporized reflux from the distillation column 28 can be used for reactivating the beds 18 , 20 , 22 in the absorption unit 14 . Thus, a conduit 50 guides the vaporized reflux back to the absorption unit 14 for purging of the beds 18 , 20 , 22 . The check valves 23 prevent reverse flow along the conduit 50 during the purging process. A cold box purge control 51 connects to the conduit 50 and diverts a portion of the vaporized reflux to maintain a slight positive pressure in the cryogenic distillation unit 16 to prevent moisture laden air from entering the unit 16 , where moisture would freeze and air condense upon contact with very cold vessels and/or piping.
[0043] Although the various heat exchangers 26 , 30 , and the condenser/reboiler are illustrated as separate units, all of the heat exchanges in the distillation unit 16 , including but not limited to the heat exchangers 26 , 30 , and the condenser/reboiler, can be constructed as a single unit. Additionally, it is to be noted that the condenser/reboiler can be separate from the distillation unit 28 . However, the condenser/reboiler preferably is disposed above the top of the distillation column 28 .
[0044] The gas separation unit 10 includes a number of thermocouples 53 and pressure sensors 55 for collecting data indications of temperature and pressure, respectively, throughout the system 10 . The system 10 also includes a number of drains 57 for draining fluids or purging air out of the system 10 for maintenance or repair purposes.
[0045] With reference to FIG. 2, a modification of the separation unit 10 is illustrated therein and identified generally by the reference numeral 10 ′. Components of the gas separation unit 10 ′ that are similar to the corresponding components of the gas separation unit 10 are identified with the same reference numeral, except that a “′” has been added thereto. These components can be constructed identically to the correspondence components of the gas separation unit 10 , except as noted below.
[0046] In the gas separation unit 10 ′, a centrifugal expander 52 communicates with the main heat exchanger 26 ′. The centrifugal expander 52 replaces the addition of liquid coolant from the liquid coolant reservoir 32 of the gas separation unit 10 (FIG. 1). In this modification, the centrifugal expander 52 compensates for process and heat leak refrigeration losses. Optionally, the additional refrigeration provided by the expander 52 can be used to liquefy part of the liquid nitrogen product as liquid or stored for later use, such as, for example, but without limitation, peak operation.
[0047] In this modification, the pressure of the oxygen rich reflux vapor discharge from the distillation column 28 ′ is reduced through an expander so as to provide the additional compensating cooling effect. In particular, after the vaporized oxygen rich reflux has entered the cold end of the main heat exchanger 26 ′, the vapor is passed through the centrifugal expander, which reduces the pressure of the reflux vapor and thus the temperature. The expanded oxygen rich reflux is then rerouted through the cool end of the main heat exchanger 26 ′. As such, the vaporized oxygen rich reflux aids in cooling the incoming pre-purified compressed air. Thus, as noted above, the vaporized oxygen rich reflux can optionally be diverted or stored for any use, or for later use, such as during peak operation.
[0048] After passing through the main heat exchanger 26 ′, the vaporized oxygen rich reflux is returned to the absorption unit 14 ′ through the conduit 50 ′. The expansion of the reflux in the centrifugal expander 52 produces energy. Preferably, the energy, in the form of a spinning shaft, is absorbed through an air or oil brake connected to the shaft of the centrifugal expander 52 .
[0049] [0049]FIG. 3 illustrates a modification of the separation unit 10 , and is identified generally by the reference numeral 10 ″. Components of the gas separation unit 10 ″ that are similar to the corresponding components of the gas separation unit 10 are identified with the same reference numeral, except that a “″” has been added thereto. These components can be constructed identically to the correspondence components of the gas separation unit 10 , and can be used with or without the expander 52 , except as noted below.
[0050] Preferably, the gas separation unit 10 ″ includes an additional device for removing hydrocarbons. In the illustrated embodiment, the unit 10 ″ includes a catalytic reactor system 54 configured to remove hydrocarbons from the air discharged from the air source 12 ″. An example of such a catalytic reactor system is known as a “Deoxo system.”
[0051] Preferably, the reactor system 54 is located upstream of the absorption beds 18 ″, 20 ″, 22 ″ and is connected to the air source 12 ″ through the conduit 36 ″. The reactor system 54 preferably includes a housing containing a catalyst. For example, the catalyst can be Platinum or Palladium. The reactor system 54 is configured to receive a stream of air from the air source 12 ″ and an amount of oxygen, and to generate a reaction between the air stream and oxygen to form water and carbon dioxide. The reactor system 54 is further configured to remove the water and carbon dioxide from the air stream.
[0052] During operation, a feed stream of air from the air source 12 ″ enters the system 54 through the conduit 36 ″. Inside the system 54 , hydrocarbons present in the air stream react with a measured amount of oxygen in the presence of a catalyst to form water and carbon dioxide. The water and carbon dioxide produced by the catalytic reaction are then removed from the air stream by the system 54 and the air stream continues onto the absorption beds 18 ″, 20 ″, 22 ″ essentially free of hydrocarbons. The operation of the system 54 is well known in the art and thus will not be described further.
[0053] With reference to FIG. 4, a housing assembly 60 is illustrated therein. The housing assembly 60 can be used to house either of the gas separation units 10 , 10 ′, 10 ″. Preferably, the housing assembly 60 comprises an air preparation unit housing 62 and a cryogenic distillation and associated heat exchanger housing 64 .
[0054] Preferably, the air preparation unit housing 62 is comprised of a frame assembly 66 defining a rectangular prism. Additionally, the housing 62 preferably includes anchoring points 68 at each of its corners. Additionally, the housing 62 preferably includes one or a plurality of removable or openable panels 70 . For example, the panels 70 can be in the form of hinged doors, panels that are completely removable, scroll-type, or sliding doors.
[0055] Preferably, the frame 66 is dimensioned so as to conform to a standard ISO size. For example, the frame 66 can be about five feet, seven feet, ten feet, twenty feet, forty, or forty-five feet long. As used herein, “length,” or “long,” refers to the longest dimension of the frame 66 , i.e., the major axis 72 . Additionally, the frame 66 can have a standard height, such as, for example, but without limitation, five feet, seven feet, eight feet, or nine and one-half feet. Additionally, the anchoring points 68 preferably conform to ISO standard anchoring points. Such anchoring points have at least two flat faces, each of which includes an aperture for connection to other anchoring points or other anchoring or connector devices.
[0056] The housing 64 includes a frame 74 . The frame 74 preferably is configured and sized to conform to at least one standard ISO container dimension. For example, but without limitation, the frame 74 can have a length along its major axis 76 of five feet, six feet, seven feet, ten feet, twenty feet, or forty feet. Additionally, the frame 74 also preferably includes anchoring points 68 at each of its corners.
[0057] With reference to FIG. 4A, one side of the housing 64 preferably includes an aperture 78 that can be aligned with an aperture on the housing 62 . Preferably, the aperture 78 includes a hinged, removable, scroll-type, or sliding door. Additionally, the frame 74 preferably includes two additional anchoring points 80 that are not positioned at a corner of the frame 74 . Rather, the additional mounting points 80 are disposed on a longitudinally-extending side of the frame 74 so as to be in alignment with two of the anchoring points 68 of the frame 66 .
[0058] For example, as shown in FIG. 4, one end of the housing 62 abuts a lower end of the housing 64 . The standard anchoring points 68 on the housing 64 are in alignment with the lower anchoring points 68 of the housing 62 . Additionally, the mounting points 80 are in alignment with the upper anchoring points 68 of the housing 62 . Thus, when the housings 62 , 64 are arranged as illustrated in FIG. 4, the mounting points 68 , 80 can be connected together to ensure a secure connection between the housings 62 , 64 and thus protect any plumbing connection between the absorption unit 14 , 14 ′, 14 ″ and the distillation and heat exchanger unit 16 , 16 ′, 16 ″. Additionally, by connecting the housings 62 , 64 as such, the housing assembly 60 is more stable and thus less likely to fall over if struck by heavy machinery or exposed to a strong wind.
[0059] For example, as shown in FIG. 5, the absorption unit 14 , 14 ′, 14 ″ is mounted within the housing 62 . Optionally, the compressor 12 can also be mounted in the housing 62 . Further, another compressor can be mounted in the housing 62 . For example, as noted above with reference to FIG. 1, a booster compressor can be used to raise the pressure of the product Nitrogen. Thus, such a booster can be mounted in the housing 62 . Additionally, the cryogenic distillation unit 16 , 16 ′, 16 ″ is mounted within the housing 64 . Preferably, the absorption unit 14 , 14 ′, 14 ″ and cryogenic distillation unit 16 , 16 ′, 16 ″ are rigidly mounted to the interior of the housings 62 , 64 , respectively. Vibration isolation devices can be used for rigidly mounting the units 14 , 14 ′, 14 ″, 16 , 16 ′, 16 ″ to the housings 62 , 64 .
[0060] As schematically shown in FIG. 1, the conduits 38 , 38 ′, 38 ″, and 50 , 50 ′, 50 ″ preferably include flanges 59 which allow the conduits 38 , 38 ′, 38 ″, 50 , 50 ′, 50 ″ to be separated in proximity to the apertures in the housings 62 , 64 . Preferably, the flanges 59 are located closer to the apertures in the housings 62 , 64 than as depicted in FIG. 1. For example, the conduits 38 , 38 ′, 38 ″, 50 , 50 ′, 50 ″ can include flat flanges disposed in proximity to the apertures in the housings 62 , 64 . Alternatively, the flanges 59 disposed on the conduits 38 , 38 ′, 38 ″, 50 , 50 ′, 50 ″ can be disposed so as to be spaced apart when the housings 62 , 64 are juxtaposed to each other. In this modification, flexible or rigid intermediate conduits can be installed between the flanges so as to complete the conduits 38 , 38 ′, 38 ″, 50 , 50 ′, 50 ″.
[0061] With reference to FIG. 6, a modification of the housing assembly 60 is illustrated therein and identified generally by the reference numeral 60 A. Components of the housing assembly 60 A similar to corresponding components of the housing assembly 60 are identified with the same reference numeral, except that a letter “A” has been added.
[0062] As shown in FIG. 6, the lower portion of the housing 64 A is aligned with a central portion of the side of the housing 62 A. Preferably, in this modification, as shown in FIG. 6A, the frame 66 A of the housing 62 A includes additional anchoring points 80 on the side of the housing 62 A that faces the housing 64 A. The additional anchoring points 80 disposed on the frame 66 A can be connected to the anchoring points 68 A, 80 A of the housing 64 A.
[0063] By connecting the housing 64 A to a central side portion of the housing 62 A, the housing assembly 60 A provides further stability and thus better protection against the risk of tip over of the housing 64 A.
[0064] With reference to FIG. 7, a further modification of the housing assembly 60 is illustrated therein and identified generally by the reference numeral 60 B. Components of the housing assembly 60 B similar to the corresponding components of the housing assemblies 60 , 60 A are identified with the same reference numeral, except that a letter “B” has been added.
[0065] As shown in FIG. 7, the housing 64 B can be connected to a side of the housing 62 B adjacent a longitudinal end thereof. The connections between the housing 62 B and 64 B of the assembly 60 B can be the same as those described above with reference to FIG. 5.
[0066] As noted above, by mounting an absorption unit in one container having standard ISO container dimensions and mounting a cryogenic distillation unit in a second container also including standard ISO container dimensions, an entire cryogenic gas separation unit can be conveniently shipped to a drilling location and quickly assembled. Additionally, because the units 14 , 14 ′, 14 ″, 16 , 16 ′, 16 ″ remain in the containers, they are well protected from hazards common at the site of a drilling operation.
[0067] Additionally, by connecting the housings 62 , 62 A, 62 B, 64 , 64 A, 64 B together using the standard ISO anchoring point hardware, the entire housing assembly 60 , 60 A, 60 B can be stabilized. This is particularly advantageous because the containers or housings 64 , 64 A, 64 B which house the cryogenic distillation units, stand on their longitudinal end in operation. Thus, connecting the housing together provides additional stability thereby lowering the risk that the housing 64 , 64 A, 64 B could tip over. Preferably, the housings 62 , 62 A, 62 B are preferably connected to the housings 64 , 64 A, 64 B with bridge fittings which provide a tension and can connect the containers so they touch each other.
[0068] While a cryogenic process to produce Nitrogen from ambient air is disclosed herein, other similar cryogenic processes can be used to produce the desired product Nitrogen. In the systems described above, refrigeration is generated by either the injection of liquid Nitrogen or by the expansion of waste gas from the distillation process to compensate for heat leak and process losses.
[0069] Other cryogenic processes can include the expansion of part or all of the inlet air to produce the required refrigeration. Such processes, including the processes disclosed above, are considered to be applicable to the present inventions.
[0070] Although these inventions have been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present inventions extend beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the inventions and obvious modifications and equivalents thereof. In addition, while several variations of the inventions have been shown and described in detail, other modifications, which are within the scope of the present inventions, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combination or sub-combinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the inventions. It should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed inventions. Thus, it is intended that the scope of the present inventions herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow. | A portable cryogenic nitrogen generator consists of an air preparation unit and a cryogenic distillation unit mounted inside separate standard-sized ISO containers that can be easily shipped to a drilling site and efficiently and quickly assembled into an operative state. The containers can be connected together at anchor points on the housings of both containers, making the nitrogen generator assembly more stable. The air preparation unit includes an absorption device and optionally includes one or a plurality of air compressor units. The cryogenic distillation unit includes a distillation column and associated heat exchangers. The air preparation and cryogenic distillation units connect through apertures in their respective containers and operate while being mounted in the containers. | 8 |
BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention relates to a rotatable spinning ring of such construction that the ring will dust automatically.
(B) Description of the Invention
In rotatable spinning rings employed heretofore in which a passive rotary ring is rotated by the frictional pressure of a traveller or in which a rotary ring is rotated transitively by the means of a driven belt, a friction wheel, or the like, and notwithstanding the torque created by the rotation of the ring, together with the prolonged period of operation, dust problems, such as spinning-mill, minute floating fibers resulting from cut-off or fallen fuzz generated by squeezing yarn fibers at the point where snail wire, traveller, or the like, come into contact with the yarn, are created. Also, various fiber oil materials sticking to fibers which have fallen as minute powders as well as floating material found in the air around the spinning ring are created, so that the material is made into a felt-like admixture by being compressed in the play of the rotary body of the rotating, that is to say, between the rotary body and the holder on the opposite side which holds the rotary body or the bearing portion thereof, resulting in a similar dust problem. The dust problems so created tend to interrupt the rotary motion of the spinning ring.
According to the kind and fineness of the spinning fibers, such as, for example, synthetic fibers, card wool, flax, silk, cotton, and mixtures of the foregoing, such fiber dusts are generated in a large quantity. As a result thereof, the frictional resistance of the sliding position of the rotary ring was increased by such use after a period of only one to three months. Also, the rotation of the spinning ring did not function smoothly, and thus resulted in unequal tension between the spindles, and also the operation of the rotary ring was impaired due to an increase of the cutting of the yarn and deterring an increase of rotation thereof. A method for preventing this problem has been the construction of means for continuously blowing away the cotton dust or the like with air under pressure and the like. This operation is undesirable since a reconstruction of the machine base was required along with the positioning of the air compressor and the necessary piping in the area. From a standpoint of the required reconstruction of machine, the increase in cost resulting therefrom and the area needed for setting up the equipment and the use of the automatic doffer being interrupted, and from the viewpoint of the cost per one spindle and such meachanism, a practical use of such a system in a large area could not be achieved satisfactorily.
SUMMARY OF THE INVENTION
The present invention is directed to a solving of the foregoing problems, and to achieve a dusting action by having the ring rotary body commence its rotary motion by means of the frictional pressure of the traveller without requiring any power from an air compressor or any other external power source. The working force so created will be sufficient to blow away or exhaust short fibers and powders in a minute state at the first stage until cotton dusts and other powdery dusts are accumulated and placed into a felt-like admixture by being gathered together and compressed. This objective may be achieved by the rotary motion of an individual ring rotary body, and also the dusting effect may be obtained by the combined action of the physical action resulting from the periphery of the rotary body and the tapered construction of the inner surface of the holder, and the air flow generated by the inclined grooves cut in the periphery of the rotaty body.
In accordance with the present invention, air flow created by the rotation of the spinning ring is generated surely and strongly from the play between the rotary body and the holder toward the outside and by means of the tapered surface formed on the peripheral surface of the spinning ring body and the inclined grooves present on such surface and the inclined groove strips on the inner surface of the dust cover, the prevention of the intrusion of dust, and the exhausting of such dust are eliminated. The ring rotary body in carried on the holder such that a fine clearance is achieved during the rotation thereby insuring that the rotation thereof is smooth. Also, in accordance with the present invention, the spinning ring body is provided with a triangular annular sliding flange which is fitted in the central portion thereof and is associated with the traingular recessed groove of the holder, so that even under all rotary conditions, there will be no deviation of the axis of the rotary body, and thereby high speed rotation is possible. Also, the upper dust cover has the additional advantage of creating a brake action, stopping the ring rotary body.
The spinning ring body in accordance with the present invention is rotated passively by the tension of spinning yarn and the frictional pressure resulting from the sliding of the traveller. This action, as compared with a ring rotated positively by other power means, reflects sensitivity to all minute tension variations for every spindle due to the variation of the bobbin winding condition from the beginning of winding to the full winding thereof, the change of the outer diameter of caps and the diameter of the bottom between chases, the rise and fall of ring rail, the unequality of sliver, the unequality in grain and shape of travellers, the difference in the quantity of the abrasion of traveller, and minute manufacturing error of ring flange and the like. Thus, the difference of rotation of the rotary body or the spinning ring of each spindle performs a so-called speed change between chases, while a cutting or braking of yarn does not occur even if a momentary abnormal tension is applied, the tension being absorbed by rotating the ring at a high speed for a few seconds. Therefore, clogging by dust cottons, as before, and the variation of yarn tension due to the difference of rotary friction of the ring itself and the generation of fuzz and melted yarn is not caused. The high speed spinning effect of the rotary ring may be continued for a longer time period, if desired, and the effect of spinning of high quality yarn at a high degree of efficiency is demonstrated.
BRIEF EXPLANATION OF THE DRAWING
FIG. 1 is a front view partially longitudinally sectioned of a spinning ring assembly made in accordance with the present invention.
FIG. 2 is an enlarged longitudinal section of the main portion of a spinning ring assembly made in accordance with the present invention showing a state of operation at the time of normal running when the ring rotary body is being rotated freely.
FIG. 3 is an enlarged longitudinal section of the main portion of a spinning ring assembly made in accordance with the present invention and showing a state of operation in which the ring rail is located in the upper position and the tension of the upper spinning yarn is decreased and the ring rotary body is associated with the holder and is borne thereby.
DESCRIPTION OF PREFERRED EMBODIMENT
As illustrated in FIGS. 1 and 2, the periphery of the spinning ring rotary body 1 is shaped so as to provide a tapered peripheral surface with increased diameter from the central portion a towards the upper and lower ends, respectively, with dust compressed interposedly being exhausted towards the upper and lower ends which are larger in outer diameter by the action of the centrifugal force created together with the rotation of the ring. The upper and lower tapered portions a 1 and a 2 of the periphery of the rotary body 1 are provided with a large number of inclined grooves c 1 , c 2 , respectively, for improving the efficiency of exhausing dust from the entire surface of the spinning ring body according to the respective direction of rotation of the ring from the central portion a of the body 1 to the respective ends a 1 and a 2 . Thus, when the body 1 is in a state wherein there is no admixture such as cotton dust or the like present in the inclined grooves c 1 and c.sub. 2, there will be no friction resistance on the rotary body, as shown in FIG. 2. Thus, the rotation of the spinning ring is increased in speed and air flow exhausted towards the respective ends a' 1 and a' 2 of the upper and lower tapered portions a 1 and a 2 is generated and thereby preventing the intrusion of dust from the upper and lower ends. In this instance, when fine dust or the like should stick or enter, the admixture will be held in the small plays d 1 and d 2 between the ring rotary body 1 and the upper and lower bearings rings 2a and 2b forming the holder 2, and will be exhausted from the upper end a' 1 and the lower end a' 2 of the tapered portions a 1 and a 2 by the application of light friction. The dust discharged from both the upper and lower ends will be removed by air flow passing over the inclinded groove strips 5" and 6" cut in the inner walls of the upper dust cover 5 and the lower dust cover 6, and which is generated by the air flow passing outside by the rotation of the spinning ring. This action also simultaneously functions to exhaust dust cotton fine particles which may stick by reason of the physical centrifugal action to the outside area. The upper and lower dust covers 5 and 6 also carry out the action of a dust cover to prevent cotton dust from falling directly on the ring and from entering into the play of the ring rotary body. The holder 2 is fixed on the ring rail 8 by a stop ring 7, with a traveller 9, a bobbin 10, a bobbin yarn 11, and the spinning yarn 12 being included in the apparatus.
The upper and lower dust covers 5 and 6 are made from an aged elastic body, such as, for example, synthetic rubber and the like, and the core portion thereof fitted on the ring rotary body 1 has inserted therein metal rings 5' and 6' respectively. The dust covers 5 and 6 are pressed on the upper and lower peripheral edges of the rotary body 1 and are affixed thereto by means of the metal rings 5' and 6', and are thinner gradually towards the peripheral edge thereof. Therefore, since there will be almost no resistance due to the frictional pressure of the traveller against the torque in a state in which there is no engagement of the plays d 1 and d 2 , and e 1 and e 2 , and the like, the ring rotary body 1 will increase its speed gradually. When the rate of rotation goes above a specified value, such as, for example, with a 47 ring, 10 inch lift, 60's acrylic synthetic spinning yarn, the number of revolutions of the spindle will be 15,000 R/M. In the case of a traveller, the number of rotations of the ring will be 5,000 R/M. The edges of the dust covers 5 and 6 will be opened slightly due to centrifugal force, and will generate a violent circulating air flow so that cotton dust around the ring will be blown away and cannot enter into the ring. Therefore, the rate of rotation of the spinning ring may be increased to 90%-95% of that of the spindle depending on the twisting factor of the spinning yarn. The dust covers 5 and 6 also function as a brake thereby preventing the spinning ring from continuously rotating inertially after the stopping of the spindle by the shutting off of the power.
When the rotation of the spinning ring is lowered and the tension of the spinning yarn is reduced due to the reduction of the frictional pressure of the traveller rotating the ring, the upper vector of the apparatus having the ring rotary body 1 upwards in the inner diameter at the intermediate position of the plays e 1 and e 2 at the bearing portion of the triangular groove of the upper and lower bearing rings 2a and 2b is reduced and the ring rotary body 1 is lowered, as shown in FIG. 3. The triangular annular sliding flange 4 is positioned against the conical surface of the triangular groove of the lower bearing ring 2b, while the periphery of the edge of the upper dust cover 5 is lowered and contacted against the upper surface of the upper bearing ring 2a and imposes a quick resistance upon the rotation of the ring, and thereby achieves the action of stopping the rotation of the ring before the stop of the rotation of the spindle. By this action, the generation of snarl due to the inertial rotation of the ring may be prevented. The plays e 1 and e 2 at the bearing portions are smaller than the plays d 1 and d 2 at the tapered inclined groove and even when the plays e 1 and e 2 are eliminted by a contacting, the plays d 1 and d 2 maintain small plays of some degree and will not interrupt the dusting function of the apparatus.
The triangular annular sliding flange 4 formed by fitting same in the recessed groove at the central portion on the periphery of the ring rotary body 1 is made of an abrasive resistant material having a non-lubricating low frictional factor, such as, for example, tetrafluoroethylene resin or the like containing a filling material. This annular sliding flange 4 is positioned at the triangular surface thereof to the inside of the smooth recessed triangular groove 3 of the holder 2 formed from the upper and lower bearing rings 2a and 2b, with very small plays e 1 and e 2 created between them and thereby forming a concave-convex triangular bearing portion in cross section therebetween. When the rotation of the spindle is low, i.e., the tension of the upper spinning yarn S and the weight of the ring rotary body 1, the ring rotary body 1 is lowered and positioned agannst the lower bearing ring 2b, and is rotated slowly. When the spindle is rotated at a high rotational speed or the tension of the spinning yarn is increased, i.e., by the tension of the upper spinning yarn S and the weight of the ring rotary body 1, the ring rotary body 1 is lifted upwards and comes into contact alternately against both the upper and lower bearing rings 2a and 2b at the bearing portion, or separated from both of them and frictional resistance is greatly reduced and a state is brought about wherein the frictional resistance between the traveller and the ring is greater than the frictional resistance at the plays e 1 and e 2 , and thereby the ring is rotated at a high speed, this being the state shown in FIG. 2. This causes such action that if the ring is rotated at a high speed when the tension of spinning yarn is small, and the ring is lowered and contacted against the lower bearing ring 2b, and friction between the traveller and the ring is reduced further, and thereby balloon collapse is increased or the generation of snarl is brought about, so that at this time point, the edge portion of the upper dust cover 5 is contacted against the upper surface of the upper bearing ring 2a of the holder and controls the overrun of the ring. When the tension of spinning yarn is increased and the ring rotary body 1 is lifted, the edge of the upper dust cover 5 is separated from the upper surface of the upper bearing ring 2a and is discontacted therefrom. When a strong torque due to the frictional pressure of the traveller acts on the ring flange the ring rotary body 1 is rotated at a high speed and air flow layer is generated in the plays e 1 and e 2 and it acts as a kind of air bearing and floats the ring rotary body 1 in the air. The ring rotary body 1 may be moved up and down by the small clearance of the plays e 1 and e 2 according to the variation of the tension of the spinning yarn, but as the bearing surfaces of the upper and lower bearing rings 2a and 2b receiving this and the contacting surfaces of the sliding flange 4 have a taper of the same angle, the center of the ring rotary portion is not biased with respect to the center of the holder portion, so that the ring can be rotated smoothly and at a high speed. In an actual spinning test in accordance with the present invention, stability was achieved completely with the ring at 17,000 R/M when the spindle is at 18,000 R/M. | A rotary spinning ring construction is provided wherein the rotary ring body is provided with upper and lower outwardly tapered body portions, each of which has its surface provided with inclined grooves, a ring holder for receiving the rotary body therein, a sliding flange positioned between the holder and the body and having some play therein, and dust caps mounted on the upper and lower portions of the rotary body to seal the upper and lower areas of play between the holder and the rotary body. This arrangement results in a spinning ring construction that will dust automatically. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This Application claims the benefit of priority and of U.S. Utility Provisional Patent Application No. 60/802,639, filed May 23, 2006, the entire disclosure of which application is expressly incorporated by reference in its entirety herein.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to aquatic extraction system and, more particularly, to an aquatic extraction system with filtration that is environmentally friendly.
(2) Description of Related Art
Conventional aquatic extraction systems are well known and have been in use for a number of years. Reference is made to the following few exemplary U.S. Patent Publications, including U.S. Pat. Nos. 3,722,685; 4,740,317; 5,160,039; 5,584,991; 5,650,073; 5,958,234; 5,993,652; 6,089,790; 6,491,818; and 6,524,028. Regrettably, most prior art aquatic extraction systems suffer from obvious disadvantages in that they are comprised of permanently fixed structures located on or near a body of water, are bulky, costly to manufacture, and expensive to maintain. Further, because they are permanently fixed, they are disruptive to the environmental ecosystem and are not esthetically pleasing when installed in a natural setting such as near a river or pond.
In addition, most other prior art water pump systems have powerful water intake units that remove or draw out massive amounts of water in a very short time. The pull or suction of water by these pumps generates a high velocity water flow (vortex) near the pump intake unit. The high rate of water flow is sufficiently strong that aquatic lives such as fish cannot escape the water current generated, and are sucked into the pump system. Therefore, regrettably, during water pumping operations, water is not the only element removed, but in addition, fish and other aquatic life is also drawn out indiscriminately by the prior art water pump systems, which threaten the ecosystem of the water source and the aquatic life therein.
Accordingly, in light of the current state of the art and the drawbacks to current aquatic extraction systems mentioned above, a need exists for an apparatus for aquatic extraction and filtration system that would be environmentally friendly. In addition, a need exists for such an apparatus that would be lightweight and portable and that would allow for varying rates of extraction of water for different applications without threatening the ecosystem of the water source and the aquatic life therein.
BRIEF SUMMARY OF THE INVENTION
One aspect of the present invention provides an aquatic extraction and filtration device that is comprised of a portable frame, piping coupled with the portable frame, and a screen enclosing the portable frame and the piping.
An optional aspect of the present invention provides an aquatic extraction and filtration device that further includes a pan coupled with the screen.
Another optional aspect of the present invention provides an aquatic extraction and filtration device wherein the portable frame is comprised of a set of compression supports and a set of lateral structural posts, with the set of compression supports and the set of lateral structural posts forming an axial length of the portable frame, and a set of bulkheads transversely coupled with the set of compression supports and the set of lateral structural, with the bulkheads forming a width of the portable frame.
Yet another optional aspect of the present invention provides an aquatic extraction and filtration device wherein the set of compression supports is comprised of hallow tubes and a commensurate set of first fasteners inserted through the hallow tubes for fastening the set of compression supports with the set of bulkheads.
Still another optional aspect of the present invention provides an aquatic extraction and filtration device wherein the set of first fasteners are comprised of all-thread, and are coupled with the set of bulkheads by nuts.
Another aspect of the present invention provides a method for extraction of water, comprising filtering and moving of water at a first rate by a pump operating at a pump rate; moving the filtered water through a set of openings at a second rate, greater than the first rate by the pump operating at the pump rate; and extracting water through the set of openings at a substantially equal rate to that of the pump rate.
Another optional aspect of the present invention provides a method for extraction of wherein the filtering and moving of water is performed at a distance away from the set of openings.
Another optional aspect of the present invention provides a method for extraction of wherein set of openings is comprised of a first set of openings and a second set of openings.
A further optional aspect of the present invention provides an aquatic extraction and filtration device wherein the set of lateral structural supports are comprised of hallow tubes that are fastened to the set of bulkheads by a set of eyebolts.
Yet a further optional aspect of the present invention provides an aquatic extraction and filtration device wherein the set of bulkheads are comprised of a groove for securing the screen therein, with the groove being proximal along an inside periphery edge of the set of bulkheads allowing transversely oriented edges of the screen along the width of the portable frame to be inserted within the groove of the set of bulkheads.
Another optional aspect of the present invention provides an aquatic extraction and filtration device wherein the piping is comprised of two main pipes that are oriented longitudinally along an axial length of the portable frame, with each pipe including two sets of slots aligned along an axial length of the pipes. A first set of slots of the two sets of slots face an exterior of the portable frame juxtaposed proximal lateral edges of the portable frame and are oriented at an angle λ degrees. A second set of slots of the two sets of slots face an interior of portable frame and are oriented at angle φ degrees. The first set of slots and the second set of slots are comprised of different sizes, with larger size slots placed away from a suction end coupled with a pumping unit for equalizing a suction velocity across an entire area of the screen, eliminating high flow areas that might impinge aquatic life.
Another aspect of the present invention provides a method for extraction of water, comprising filtering and moving of water at a first flow rate by a pump, then moving the filtered water through a set of openings at a second flow rate, greater than the first flow rate by the pump, and finally extracting water through the set of openings at a substantially equal flow rate to that of a third flow rate of water that moves through the pump.
Another optional aspect of the present invention provides a method for extraction of water wherein the filtering and moving of water is performed at a distance away from the set of openings.
These and other features, aspects, and advantages of the invention will be apparent to those skilled in the art from the following detailed description of preferred non-limiting exemplary embodiments, taken together with the drawings and the claims that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
It is to be understood that the drawings are to be used for the purposes of exemplary illustration only and not as a definition of the limits of the invention. Throughout the disclosure, the word “exemplary” is used exclusively to mean “serving as an example, instance, or illustration.” Any embodiment described as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.
Referring to the drawings in which like reference character(s) present corresponding part(s) throughout:
FIGS. 1A and 1B are an exemplary overview illustration of environments within which the aquatic extraction and filtration device of the present invention may be used in accordance with the present invention;
FIG. 2 is an exemplary perspective illustration of an aquatic extraction and filtration device in accordance with the present invention;
FIG. 3A is an exemplary perspective illustration of the aquatic extraction and filtration device 100 illustrated in FIG. 2 , showing a disassemble view of the screen in accordance with the present invention;
FIG. 3B is an exemplary perspective illustration of one of the bulkheads in accordance with the present invention;
FIG. 3C is an exemplary enlarged perspective illustration of a section of the bulkhead illustrated in FIG. 3B in accordance with the present invention;
FIG. 3D is an exemplary perspective close-up view of the assembled screen with one of one of the bulkheads in accordance with the present invention;
FIG. 4 is an exemplary perspective illustration of the aquatic extraction and filtration device with the screen partially removed, in accordance with the present invention;
FIG. 5 is an exemplary perspective illustration of the aquatic extraction and filtration device with the bulkheads, screen and the pan removed only showing the internal portable frame and plumbing in accordance with the present invention;
FIG. 6 is an exemplary perspective illustration of an eyebolt used for coupling the bulkheads in accordance with the present invention;
FIG. 7A is an exemplary top view illustration of the aquatic extraction and filtration device in accordance with the present invention;
FIG. 7B is an exemplary top view illustration of the first bulkhead in accordance with the present invention, and FIG. 7C is an exemplary top view illustration of the second bulkhead in accordance with the present invention;
FIG. 7D is an exemplary side view illustration of the aquatic extraction and filtration device in accordance with the present invention;
FIG. 7E is an exemplary top view illustration of the aquatic extraction and filtration device for a second plumbing option in accordance with the present invention;
FIG. 7F is an exemplary top view illustration of the first bulkhead in accordance with the present invention;
FIG. 7G is an exemplary top view illustration of the second bulkhead used with the second embodiment illustrated in FIG. 7E in accordance with the present invention;
FIG. 7H is an exemplary perspective illustration of a set of plugs used with the second embodiment illustrated in FIGS. 7E and 7G .
FIG. 8 is an exemplary illustration that maps the various preferred orientations, distances, and sizes of the slots or apertures that are on the preferred two-pipe system of the aquatic extraction and filtration device in accordance with the present invention;
FIGS. 9A and 9B are exemplary illustrations of one or more aquatic extraction and filtration device coupled with one another in series and/or in parallel combinations in accordance with the present invention;
FIGS. 10A , 10 B, and 10 C are exemplary illustrations of alternative embodiments for various configurations of the inner plumbing of the aquatic extraction and filtration device that use plurality of parallel tubes in accordance with the present invention; and
FIGS. 11A to 11L are exemplary illustrations that map the various orientations of the slots or apertures for the various embodiments for the plumbing systems for different embodiments of the aquatic extraction and filtration device illustrated in FIGS. 10A to 10C in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The detailed description set forth below in connection with the appended drawings is intended as a description of presently preferred embodiments of the invention and is not intended to represent the only forms in which the present invention may be constructed and or utilized.
Various jurisdictional regulations have been instituted that require the preservation of marine life, regardless of the reason for which water is extracted from various water sources such as lakes, ponds, rivers or others. The present invention provides an environmentally friendly aquatic extraction and filtration device that is portable, lightweight, has low profile, and provides effective, economic means of protecting aquatic life and, further, provides protection for the equipment used for water extraction. The present invention reduces the “approach” velocity of the water proximal a protective screen of the aquatic extraction and filtration device of the present invention, enabling aquatic life such as fish to swim away from the device. The approach velocity of water is the velocity (speed and direction) that water flows through the protective screen of the present invention. That is, it is the momentum (mass and velocity) of the water current being impinged upon the screen. The present invention therefore, prevents aquatic life from being impaled or impinged on the protective screen of the present invention, and from being ingested into the pump stream. Further, although the “approach” velocity of the water proximal the protective screen is reduced to a level that protects aquatic life, the present invention maintains the rate of water pumped and in fact, the rate of water extracted is easily controlled by variation in the dimensions of the device of the present invention. Therefore, in order to maintain a low level of approach velocity of water, if the pumping rate of the water is increased, then the size of the screen is commensurately increased. This way, a large volume of water flows over a larger surface area, neutralizing, maintaining, or in fact, reducing the actual approach velocity of the water near the protective screen, despite an increase in the rate of water pumped.
FIGS. 1A and 1B are an exemplary overview illustration of typical environments within which the aquatic extraction and filtration device 100 of the present invention is mostly used, which are ponds, rivers, and other natural bodies of water. The aquatic extraction and filtration device 100 of the present invention may be coupled with a water pump system 102 to extract water 104 from a body of water, which may eventual be used to fight fire, such as in wild land firefighting situations. The present invention can be immersed and placed at the bottom floor of the body of water, or be floated by a buoyant or a floatation device. Although not illustrated, for deep waters, the aquatic extraction and filtration device 100 of the present invention may also be simply immersed within water at any orientation.
The aquatic extraction and filtration device 100 of the present invention may be described in terms of three main sections, which include a screen, a framework, and internal plumbing. The screen assembly includes the screen and connection units, is the filtering part of the device, and further forms an enclosure for the device. The portable frame of the aquatic extraction and filtration device 100 of the present invention functions to give the device its low profile, and allows the screen to wrap around the portable frame giving the screen additional surface area for the given screen size. The low profile of the portable frame allows drafting in shallow water situations, and decreases the overall weight of the aquatic extraction and filtration device 100 . The portable frame further includes a pair of bulkheads, which form the shape of the screen and block the water flow of the stream, eliminating unwanted excessive “approach velocities” that might impinge aquatic life or debris to the screen surface. Exemplary eyebolts attach the bulkheads and the outer portable frame tubes, and provide an attachment point for securing or suspending the device in the water source. A carry sling (not shown) may be attached to the eyebolts. The screen enclosure and the portable frame form a housing for the internal plumbing, which is comprised of main pipes having slots, through which water is pumped, and includes optional periphery plumbing such as “T” and elbow configuration pipes for connection of the main pipes to the pump. The main pipes of the internal plumbing are slotted, with slot sizes increasing as they progress along the length of the pipes (away from the pump) and are aligned at certain angles. This configuration distributes the suction flow of water evenly across the entire screen surface.
FIG. 2 is an exemplary perspective illustration of an aquatic extraction and filtration device 100 in accordance with the present invention, and FIG. 3A is an exemplary perspective illustration of the aquatic extraction and filtration device 100 illustrated in FIG. 2 , showing a disassemble view of the screen 202 . As illustrated in both FIGS. 2 and 3A , the aquatic extraction and filtration device 100 is comprised of a single piece, unitary screen 202 that wraps around a portable frame, and functions as a filter. The screen 202 of the aquatic extraction and filtration device 100 is longitudinally configured into a structure having a plurality of straight or flat sides and two curved or rounded lateral edges, spanning longitudinally along an axial length L of the aquatic extraction and filtration device 100 .
The top section 204 of the screen 202 includes the middle portion 224 , and the bottom section 350 ( FIG. 3A ) includes a corresponding middle portion that is comprised of the two end sections 352 and 354 of the screen. When assembled, the middle portion 224 is parallel to the coupled end sections 352 and 354 , parallel along the axial length L of aquatic extraction and filtration device 100 . The top section 204 further includes two top lateral portions 206 and 208 that are bent at an angle θ relative to the surface of the middle portion 224 , and have an axial length L. The screen 202 further includes the curved or rounded lateral edges 214 and 226 , which are common to both top and bottom sections 204 and 350 , and which curve or bend to form the two bottom lateral portions 304 and 344 of the screen. The two bottom lateral portions 304 and 344 are bent at an angle θ, relative to the surface of the screen ends 352 and 354 that are substantially horizontally oriented. As further illustrated in FIG. 3A , couplers 332 , 334 , and 336 in the form of slats couple the screen ends 352 and 354 with one another to shape the bottom middle portion, which is parallel with the top middle portion 224 . The slat couplers 332 , 334 , and 336 may be coupled with the screen ends 352 and 354 by a variety of mechanisms, a non-limiting example of which may be the use of screws 374 .
As illustrated in FIG. 3A , the screen 202 is capped by a front side 210 and a backside 310 that are parallel in relation to one another, and are transversely coupled with the longitudinally oriented sides of the screen 202 to form the width of the aquatic extraction and filtration device 100 . The front side 210 and the backside 310 (collectively known as bulkheads) form a part of the portable frame, and enclose the screen 202 at axial ends. The screen 202 is detachably fixed on to the bulkheads 210 and 310 . The detachably removable bulkheads 210 and 310 provide easy access to within the enclosure (formed by the screen 202 ) for replacement of the inside components of the aquatic extraction and filtration device 100 . It should be noted that although bulkheads are referred to as either “front side 210 ” and the “backside 310 ,” both bulkheads are identical, and can function as the front or back sides. Of course, regardless of the nomenclature, the water flow through the device 100 is only in one direction. That is, the aquatic extraction and filtration device 100 can only be coupled between the water source and the pump in only one way due to its internal plumbing configuration. Stated otherwise, the actual bulkheads may be interchangeable, but the direction in which the actual aquatic extraction and filtration device 100 of the present invention is coupled between the water source and the pump is specifically in only one orientation, which is dictated by the internal plumbing configuration.
FIG. 3B is an exemplary perspective illustration of one of the bulkheads, showing the details of the grooves for securing the screen 202 therein, FIG. 3C is an exemplary enlarged perspective illustration of a section of the bulkhead illustrated in FIG. 3B , and FIG. 3D is an exemplary perspective close-up view of the assembled screen with one of one of the bulkheads. As best illustrated in FIGS. 3B and 3C , the bulkheads 210 and 310 further includes a groove 364 proximal along an inside periphery edge of the bulkheads 210 and 310 having an approximate width of about ¼ inch and an approximate depth of ⅜ inch. The groove 364 of the bulkheads 210 and 310 is used to help secure the screen 202 to the respective bulkheads 210 and 310 , and maintain and secure the structural integrity of the screen 202 . In other words, the transversely oriented edges of the screen along the width W of the device 100 are inserted within the groove 364 of the bulkheads 210 and 310 , and secured therein as illustrated in FIGS. 2 and 3D . Reference 250 exemplarily illustrates the hidden portion of the one screen edge within the groove 364 of the bulkhead 310 .
It should be noted that transversely oriented edges of the screen 202 along the width W of the device 100 are first inserted within the groove 364 of the bulkheads 210 and 310 , and then the slats 332 , 334 , and 336 are used to couple the screen ends 352 and 354 . That is, after the portable frame is first made, the inner plumbing is made second, and the bulkheads are coupled with the portable frame, next, the screen 202 is assembled in accordance with the above description. The screen 202 is wrapped first, tightened, and then slats 332 , 334 , and 336 are used to coupled the screen ends 352 and 354 . Finally, a sealant is used around the bulkhead grooves 364 . At the end, an optional pan 338 is placed and affixed to the exterior of the screen enclosure 202 .
As stated, further included with the aquatic extraction and filtration system 100 is an optional pan 338 , which is substantially configured commensurate with the longitudinal axial sides of the screen 202 . That is, it includes a middle portion 356 and two lateral ends 340 and 342 , with the lateral ends 340 and 342 bent at an angle to substantially match the bent angle of two bottom lateral portions 304 and 344 of the screen 202 . The optional pan 338 is coupled to the exterior of the screen 202 , and functions to prevent debris being sucked into the screen, i.e., granulated (fine) sands, rocks, or other debris. In other words, the pan 338 acts as a shield between the screen 202 and the water floor, preventing debris from being introduced into the pump system, which reduces the deterioration of the pumps. In general, the amount of surface area covered by the pan 338 is compensated by an increase in the surface area of the screen 202 that is exposed. Hence, the screen area required to maintain a maximum “approach velocity” for water and to move or pump through a desired amount of water is determined based on the exposed portion of the screen 202 . Of course, without the pan 338 the surface area of the screen 202 will be exposed more and therefore, the overall size of the device 100 can be reduced. The pan 338 on the bottom allows the aquatic extraction and filtration device 100 to be placed anywhere in the water basin without hampering its operation. It should be noted that without the use of the pan, the location of the various slot orientations on the internal pipes (described below) would change for efficient operation of the aquatic extraction and filtration device 100 .
FIGS. 4 to 6 are exemplary illustrations of the aquatic extraction and filtration device 100 , showing its frame and internal plumbing. FIG. 4 is an exemplary perspective illustration of the aquatic extraction and filtration device 100 with the screen 202 partially removed, FIG. 5 is an exemplary perspective illustration of the aquatic extraction and filtration device 100 with the bulkheads, screen and the pan removed only showing the internal frame and plumbing, and FIG. 6 is an exemplary perspective illustration of an eyebolt. As illustrated in the FIGS. 4 to 6 , the portable frame of the aquatic extraction and filtration device 100 is generally comprised of two or more hallow, lateral structural posts 410 and 412 that coupled the bulkheads 210 and 310 and define the axial length (longitudinally) of the aquatic extraction and filtration device 100 . The lateral structural posts also facilitate in forming the shape of the screen 202 , in particular, the curved or rounded lateral edges 214 and 216 thereof, and prevent the screen enclosure 202 from collapsing longitudinally. Non-limiting examples of materials for the structural posts may include a 60/61 T6 Aluminum, where (60/61 is the alloy composition, and T6 is the brittleness of the Aluminum). In other words, the two or more structural posts 410 and 412 must be strong, and cannot flex. Of course, any material that is not flexible, is ridged, strong, and can resist corrosion may be used, a non-limiting example of which may include high-density polyethylene. The axial lengths of the structural posts depend on the size of the aquatic extraction and filtration device 100 .
As best illustrated in FIGS. 4 and 5 , further included as part of the overall portable frame of the aquatic extraction and filtration device 100 are substantially centrally located hallow compression supports 458 , 502 , 504 , and 506 that include within their longitudinally oriented hallow chambers a respective set of all-threads 456 , 450 , 440 , and 448 . As with the lateral structural posts 410 and 412 , the compression supports 458 , 502 , 504 , and 506 couple and tighten the bulkheads 210 and 310 together and define the axial length (longitudinally) of the aquatic extraction and filtration device 100 . The compression supports 458 , 502 , 504 , and 506 also facilitate in forming the shape of the screen 202 , in particular, the middle portion 224 , lateral portions 206 and 208 , bottom lateral portions 304 and 344 , screen ends 352 and 354 thereof, and prevent the screen 202 from collapsing longitudinally. Accordingly, the lateral posts 410 and 412 pull the screen 202 laterally and the compression supports 458 , 502 , 504 , and 506 maintain the screen 202 up and above the internal pipes so that the screen 202 does not rest on the pipes, in particular, preventing the screen enclosure from blocking the various apertures aligned along the internal pipes. This also improves the flow of water within the space created between the compression supports 458 , 502 , 504 , and 506 and the internal pipes. Non-limiting examples of materials for the compression supports 458 , 502 , 504 , and 506 may include a 60/61 T6 Aluminum, where (60/61 is the alloy composition, and T6 is the brittleness of the Aluminum). In other words, the compression supports 458 , 502 , 504 , and 506 must be strong, and cannot flex. Of course, any material that is not flexible, is ridged, strong, and can resist corrosion may be used, a non-limiting example of which may include high-density polyethylene. The axial lengths of the compression supports 458 , 502 , 504 , and 506 depend on the size of the aquatic extraction and filtration device 100 .
As further illustrated in FIG. 4 , the portable frame of the aquatic extraction and filtration device 100 is further comprised of the bulkheads 210 and 310 , which define the transverse shape of the portable frame. The bulkheads 210 and 310 function to cap the screen 202 at its transversely oriented sides, and are detachably coupled with one another by the posts 410 and 412 and the compression supports 458 , 502 , 504 , and 506 . The posts 410 and 412 are coupled to the bulkheads through a first set of respective apertures 362 and 366 , and 370 and 372 by a first set of fasteners. The compression supports 458 , 502 , 504 , and 506 are coupled to the bulkheads through a second set of respective apertures 360 and 380 , 320 and 328 , 324 and 382 , 326 and 368 by a second set of fasteners. Non-limiting examples of first set of fasteners may include a set of eyebolts 400 , 402 , 406 , 408 , and that of second set of fasteners nuts 440 that couple through the respective all-threads 456 , 450 , 440 , and 448 of the respective compression supports 458 , 502 , 504 , and 506 . The bulkhead 310 is a mirror image of the bulkhead 210 .
The eyebolts attach the bulkheads 210 and 310 with the posts 410 and 412 , and provide an attachment point for securing or suspending the device 100 in water. They are also accommodating for carrying an optional sling to be attached thereto. The eyebolts 400 , 402 , 406 , and 408 may be used to suspend the aquatic extraction and filtration device 100 from a floating platform so it can be poised within the body of water. In addition, the eyebolts 400 , 402 , 406 , and 408 enable the securing of the aquatic filtration device 100 in a fast flowing stream of water. The eyebolts provide attachment points on which to secure the screen in position in the water current, suspend it, or relocate it in the water source, without disconnecting it or entering the water to make a positioning adjustment. As best illustrated in FIG. 6 , the eyebolts include a washer 602 , which facilitates further tightening of the bulkheads together.
FIGS. 5 and 7A to 7 G detail the various embodiments of the plumbing options of the aquatic extraction and filtration device 100 . FIG. 7A is an exemplary top view illustration of the aquatic extraction and filtration device 100 , FIG. 7B is an exemplary top view illustration of the first bulkhead ( 210 ), FIG. 7C is an exemplary top view illustration of the second bulkhead ( 310 ), and FIG. 7D is an exemplary side view illustration of the aquatic extraction and filtration device 100 . The bulkheads 210 and 310 have respective central opening 212 and 312 to accommodate for the respective “T” plumbing 536 and 544 , with one of the “T” pluming (either 536 or 544 ) coupled to a cam lock 230 ( FIG. 2 ). As further illustrated in FIGS. 5 and 7A , the aquatic extraction and filtration device 100 is comprised of two main pipes 532 and 540 , four pipes of elbow configuration 530 , 534 , 538 , and 542 , and two pipes of “T” configuration 536 and 544 , all of which are housed within the screen 202 . The two main pipes 532 and 540 are adjoined at the openings 212 and 312 of the respective bulkheads 210 and 310 by the “T” and elbow configuration pipes. That is, a first end of the main pipes 532 and 540 are coupled with two elbow configuration pipes 534 and 538 , these, in turn, are coupled with one another with a “T” form pipe 536 . The second end of the main pipes 532 and 540 are coupled with two other elbow configuration pipes 530 and 542 , these, in turn, are coupled with one another with a “T” form pipe 544 . The two main pipes 532 and 540 include one or more apertures or slots of different sizes thereon for suction of water (described in detail below). The pan 338 is coupled to the aquatic extraction and filtration device 100 via an exemplary set of fasteners 712 and 714 , illustrated in FIGS. 7B and 7C .
FIGS. 7E to 7H are exemplary illustrations of another embodiment of the aquatic extraction and filtration device 100 that use a different plumbing option. This embodiment of the aquatic extraction and filtration device 100 includes similar corresponding or equivalent components as those shown in the previous FIGS. 1A to 7D , and described above. Therefore, for the sake of brevity, clarity, convenience, and to avoid duplication, the general description of FIGS. 7E to 7H will not repeat every corresponding or equivalent component that has already been described above in relation to the aquatic extraction and filtration device 100 that is shown in FIGS. 1A to 7D .
FIG. 7E is an exemplary top view illustration of the aquatic extraction and filtration device 100 for the second plumbing option, FIG. 7F is an exemplary top view illustration of the first bulkhead ( 210 ), FIG. 7G is an exemplary top view illustration of the second bulkhead ( 710 ), and FIG. 7H is an exemplary perspective illustration of the plugs used with the second embodiment illustrated in FIGS. 7E and 7G . As illustrated, the aquatic extraction and filtration system of 100 includes only the single “T” configuration pipe 536 at a first end. At the other end of the aquatic extraction and filtration system of 100 , the “T” configured pipe 544 , and the elbow-configured pipes 542 and 530 (all illustrated in FIG. 7A ) are removed. Of course, given that the bulkheads 210 and 310 are identical, the “T” configured pipe 544 , and the elbow-configured pipes 542 and 530 could remain and, instead, the “T” configured pipe 536 , and the elbow-configured pipes 538 and 534 removed. With this embodiment, the bulkhead 310 is replaced with bulkhead 710 , which includes plugs 702 and 704 ( FIGS. 7G and 7H ) that are directly inserted into the open ends of the main pipes 532 and 540 when the bulkhead 710 is coupled with the aquatic extraction and filtration device of 100 , as illustrated in FIG. 7E . The plugs 702 and 704 are comprised of thick cylinder that are fastened to the bulkhead 710 by fasteners. The diameter of the plugs 702 and 704 is smaller than the interior diameter of the pipes 532 and 540 to allow the plugs 702 and 704 to be inserted therein. The main pipes 540 and 532 mount onto the respective plugs 702 and 704 , which secure the position of the pipes 540 and 532 . The plugs 702 and 704 are secured (pulled in) further inside the pipes 540 and 532 when the compression supports 458 , 502 , 504 , and 506 are tightened by the second set of fasteners. It should be noted that bulkhead 710 also differs from that of bulkhead 310 by removing (closure of) the aperture 312 .
FIG. 8 is an exemplary illustration that maps the various preferred orientations and sizes of the slots or apertures that are on the preferred two pipe system (two main straight pipes 540 and 532 ). As illustrated in FIG. 8 , each of the pipes 540 and 532 has two sets of slots. The slots 801 to 814 facing the exterior of the screen enclosure 202 juxtaposed proximal the curved or rounded lateral edges 214 and 216 are at λ degrees orientation as illustrate by the reference number 840 , and the slots 820 to 833 facing the interior of the screen enclosure 202 are oriented at φ degrees as illustrated by the reference number 842 . The varying sizes of the slots help equalize the suction velocity across the entire area of the screen, eliminating high flow areas that might impinge aquatic life or debris. The interior slots 820 to 833 are oriented at φ degrees, which provide a balance of flow. For the embodiment of the aquatic extraction and filtration device 100 that uses the optional pan 338 , the interior slots 820 to 830 are lowered towards the ground (the pan) for better disbursement of water, and a more constant flow rate, eliminating hot spots (which are specific locations on the screen where high speed flow rates of water current takes place). The size and slot orientations assures that no hot spots or dead spots (where there is no flow rate of current) are created any where on the screen, and that all flow rates of water 852 impaled or impinged onto the screen is uniform and equal, and is below some jurisdictional standard. The distance 850 between the apertures, and the apertures and the screen is important. Appropriate distances 850 between the apertures allows for even distribution of water flow across the device 100 . In addition, the further away the screen is placed from the apertures the more disbursed the flow of the water. Furthermore, larger apertures are placed away from the suction ends 860 and 862 (where the pump is coupled) to reduce vortex.
FIGS. 9A and 9B are exemplary illustrations of one or more aquatic extraction and filtration device 100 coupled with one another in series and in parallel combinations. Each device 100 must be oriented in a specified direction dictated by the internal plumbing. That is, as was described in relation to FIG. 8 , the internal plumbing, in particular, the main pipes 540 and 532 have a set of openings that progressively increase in size, with the smallest opening at one end (proximal the pump), and the largest at the other (distal from the pump). The direction in which the aquatic extraction and filtration device 100 is oriented for connection between a water source and the pump is that the largest sized opening must be distal from the pump, and the smallest must be proximal to the pump. This configuration applies to one or multiple series or parallel connections of device 100 .
As illustrated, multiple screens can be joined together in series ( FIG. 9A ) and or parallel ( FIG. 9B ), the series configuration reduces the need for frequent cleansing in high debris water sources, the parallel configuration, plumbed with manifold in multiples, will allow larger volume pumps to be used with the same size screen. With series configuration, the need for frequent cleaning is reduced because if screen “A” on the aquatic extraction and filtration device 100 becomes clogged with dirt and debris, most of the water suction will be compensated through screen “B” of the second series connected aquatic extraction and filtration device 100 . In other words, one of the clean screens “A” or “B” will take over the slack from the other screen “A” or “B” that is clogged. For example, the more clogged the aquatic extraction and filtration device “A” becomes, the more water will be removed from the other aquatic extraction and filtration device “B.” It should be noted that the flow rate of water into the pump would remain the same (balanced) due to the series connection of the two aquatic extraction and filtration devices “A” and “B.” It should be apparent to those skilled in the art that the embodiment illustrated and described in FIGS. 7E to 7H cannot be used in the series connection as the first unit (the unit coupled closest to the pump, in this instance, unit “B”). The end unit (unit “A”) can use any of the embodiments illustrated in FIGS. 7A to 7H in the series connection. With parallel connections, if one of the aquatic extraction and filtration systems “C” or “D” becomes clogged, then the total rate of water flow pumped would be reduced by the amount that the clogged aquatic extraction and filtration device (“C” or “D”) was extracting water. Although not illustrated, it should readily be apparent to those skilled in the art that any combination or permutations of parallel and or series connection of the aquatic extraction and filtration devices can be made. Hence, for example, the aquatic extraction and filtration devices “C” and “D” can each have additional series connected aquatic extraction and filtration devices, making a parallel/series combination.
It should be noted that cleaning the screen 202 of debris build up is accomplished easily by back flushing the device from the water storage tanks or bladders, by adding a gated “Y” to the intake hose and connecting a hose to the discharge side of the pump, and pumping from the storage. This will blast the screen clean. It should further be noted that there are no moving parts to ware, and no internal parts that could break and become ingested into the pump, damaging vital component parts.
FIGS. 10A , 10 B, and 10 C are exemplary illustrations of alternative embodiments for various configurations of the inner plumbing of the respective aquatic extraction and filtration devices 1000 , 1002 , and 1004 , where instead of using the preferred two main straight pipes 540 and 532 , a plurality thereof is used. Hence, as illustrated, a variety of plumbing configurations may be attained by attaching the straight pipes in pairs or gangs. However, it is preferable to use two straight pipes rather than a plurality thereof. The use of two straight pipes as illustrated in the previous figures will produce a “captive” area for the water flow, and produce the greatest disturbance to reduce turbulence. The use of a center pipes 1008 will create a hot spot because in general, water tends to move in a straight direction, therefore, water will be sucked into the pump mainly through the center tube, leaving the others underutilized, thereby creating a hot spot surrounding the center tubes (and the central portion of the aquatic extraction and filtration device 100 ). With respect to the configurations 1000 and 1004 , substantial space is used that is wasted, without much advantage.
FIGS. 11A to 11L are exemplary illustrations that map the various orientations and sizes of the slots or apertures for the various embodiments for the plumbing system for different embodiments of the aquatic extraction and filtration device 100 illustrated in FIGS. 1A to 10C . Orientation and sizes of the slots dictate the flow rate and direction of water into the slotted pipes, with the goal of equalizing the flow rate over the entire screen area. Accordingly, FIGS. 11A to 11L provide a mapping for an exemplary set of slot orientation and size for different embodiments of the aquatic extraction and filtration device 100 .
FIG. 11A is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 with a bottom pan 338 , having a preferred two pipe configuration showing exemplary slot location angles (also illustrated and described above with respect to FIGS. 1A to 9B ). As illustrated, with this preferred exemplary embodiment, a first set of slots “ 1 ” and “ 2 ” on pipes 540 and 532 face the exterior of the enclosure juxtaposed proximal the curved or rounded lateral edges 214 and 216 , and are oriented at an angle λ degrees orientation, with an exemplary value of about 0°/180°. The second set of slots “ 3 ” and “ 4 ” face the interior of the screen enclosure, and are oriented at φ degrees, with an exemplary value of 45 degrees (+/−) from the 0°/18.0° reference. It should be noted that within the context of FIGS. 11A to 11L , each set of slots illustrated (e.g., set of slots “ 1 ”) includes a plurality of individual slots aligned along the axial length of a pipe.
FIG. 11B is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 with a bottom pan having a four pipe configuration (illustrated in FIG. 10A ) exemplary showing slot location angles. The four pipe configuration illustrated includes similar corresponding or equivalent components as the two pipe configuration that is shown in FIG. 11A , and described above. Therefore, for the sake of brevity, clarity, convenience, and to avoid duplication, the general description of FIG. 11B will not repeat every corresponding or equivalent component that has already been described above in relation to the two pipe configuration that is shown in FIG. 11A . As illustrated, with this exemplary embodiment, the two interior pipes 1106 and 1108 include respective distal slots “ 5 ” and “ 6 ” that are oriented at an angle φ degrees orientation, with an exemplary value of 45 degrees (+/−) from the 0°/180° reference. The interior pipes 1106 and 1108 further include respective proximal slots “ 7 ” and “ 8 ” that are also oriented at an angle φ degrees orientation, with an exemplary value of 45 degrees (+/−) from the 0°/180° reference.
FIG. 11C is an exemplary cross-sectional illustration of the aquatic extraction and filtration devices 100 without a bottom pan having a two pipe configuration showing exemplary slot location angles (also illustrated and described above with respect to FIGS. 1A to 9B , and 11 A). As illustrated, with this exemplary embodiment, a first set of slots “ 1 ” and “ 2 ” on pipes 1104 and 1102 face the exterior of the enclosure juxtaposed proximal the curved or rounded lateral edges 214 and 216 , and are oriented at an angle λ degrees orientation, with an exemplary value of about 0°/180°. The second set of slots “ 9 ” and “ 10 ” face the interior of the screen enclosure, and are oriented at γ degrees, with an exemplary value of 22.5 degrees (+/−) from the 0°/180° reference. The final set of slots “ 11 ” and “ 12 ” face the interior of the screen enclosure, and are oriented at δ degrees, with an exemplary value of 22.5 degrees (+/−) from the 0°/180° reference.
FIG. 11D is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 without a bottom pan having a four pipe configuration (illustrated in FIG. 10A ) showing exemplary slot location angles. The four pipe configuration without the bottom pan includes similar corresponding or equivalent components as the two pipe configuration that is shown in FIG. 11C , and described above. Therefore, for the sake of brevity, clarity, convenience, and to avoid duplication, the general description of FIG. 11D will not repeat every corresponding or equivalent component that has already been described above in relation to the four-pipe configuration without the bottom pan that is shown in FIG. 11C . As illustrated, with this exemplary embodiment, the two interior pipes 1106 and 1108 include four sets of slots (with each set including a plurality of slots aligned along the axial length of the pipes), including slots sets “ 13 ,” “ 14 ,” “ 15 ,” “ 16 ,” “ 17 ,” “ 18 ,” “ 9 ,” and “ 20 ” are oriented at an angle η degrees orientation, with an exemplary value of 11.25 degrees (+/−) from the 0°/180° reference. In other words, the pairs of set of slots 13 and 14 , 15 and 16 , 17 and 18 , and 19 and 20 have an exemplary 22.5 degree separation.
It should be noted that the size of each individual slot is decreased commensurately as the number of slots increases. This is to maintain the aggregate size of the individual slots equal to the cross-sectional diameter of the pipe. Increasing the sizes of the slots (or maintaining their size, and increasing their number) so that the collective total size of the slot openings is larger than that of the cross-sectional diameter of the pip does not provide additional advantage because the amount of water moved through the pipe will continue to be limited by the cross-sectional diameter size of the pipe, no matter how many or how large of slots. Therefore, the total, collective opening size of the slots (regardless of number of slots) should at most equal to that of the cross-sectional diameter of the pipe. Accordingly, for example, if the number of slots is doubled (in case of pipes 1106 and 1108 illustrated in FIG. 11D versus that which is illustrated in FIG. 11B ), the size of each slot within the set of slots should be reduced by a half.
FIG. 11E is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 without a bottom pan having a two pipe configuration (illustrated in FIG. 10A ) showing exemplary slot location angles. As illustrated, with this exemplary embodiment, a first set of slots “ 1 ” and “ 2 ” on pipes 1104 and 1102 face the exterior of the enclosure juxtaposed proximal the curved or rounded lateral edges 214 and 216 , and are oriented at an angle λ degrees orientation, with an exemplary value of about 0°/180°. The second set of slots “ 21 ” and “ 22 ” face the interior of the screen enclosure, and are oriented at ζ degrees, with an exemplary value of 0°/180°.
FIG. 11F is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 without a bottom pan having a four pipe configuration (illustrated in FIG. 10A ) showing exemplary slot location angles. The four pipe configuration without a bottom pan includes similar corresponding or equivalent components as the two pipe configuration that is shown in FIG. 11E , and described above. Therefore, for the sake of brevity, clarity, convenience, and to avoid duplication, the general description of FIG. 11F will not repeat every corresponding or equivalent component that has already been described above in relation to the two pipe configuration that is shown in FIG. 11E . As illustrated, with this exemplary embodiment, the two interior pipes 1106 and 1108 include two sets of slots (with each set including a plurality of slots aligned along the axial length of the pipes), including slots sets “ 23 ,” “ 24 ,” “ 25 ,” and “ 26 ” that are oriented at an angle ζ degrees orientation, with an exemplary value of 0°/180°.
FIG. 11G is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 with a bottom pan having a three pipe configuration (illustrated in FIG. 10B ) showing exemplary slot location angles. As illustrated, with this exemplary embodiment, a first set of slots “ 1 ” and “ 2 ” on pipes 1104 and 1102 face the exterior of the enclosure juxtaposed proximal the curved or rounded lateral edges 214 and 216 , and are oriented at an angle λ degrees orientation, with an exemplary value of about 0°/180°. The second set of slots “ 27 ” and “ 30 ” face the interior of the screen enclosure, and are oriented at δ degrees, with an exemplary value of 22.5 degrees (+/−) from the 0°/180° reference. The sets of slots 28 and 29 for pipe 1110 are also oriented at δ degrees, with an exemplary value of 22.5 degrees (+/−) from the 0°/180° reference.
FIG. 11H is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 with a bottom pan having a six pipe configuration showing exemplary slot location angles. The six pipe configuration with the bottom pan includes similar corresponding or equivalent components as the three pipe configuration that is shown in FIG. 11G , and described above. Therefore, for the sake of brevity, clarity, convenience, and to avoid duplication, the general description of FIG. 11H will not repeat every corresponding or equivalent component that has already been described above in relation to the three pipe configuration that is shown in FIG. 10G . As illustrated, with this exemplary embodiment, each of the four interior pipes 1112 to 1118 include two sets of slots (with each set including a plurality of slots aligned along the axial length of the pipes), including slots sets “ 31 ” to “ 38 ” that are oriented at an angle δ degrees orientation, with an exemplary value 22.5 degrees from 0°/180° reference.
FIG. 11I is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 without a bottom pan having a three pipe configuration (illustrated in FIG. 10B ) showing exemplary slot location angles. As illustrated, with this exemplary embodiment, a first set of slots “ 1 ” and “ 2 ” on pipes 1104 and 1102 face the exterior of the enclosure juxtaposed proximal the curved or rounded lateral edges 214 and 216 , and are oriented at an angle λ degrees orientation, with an exemplary value of about 0°/180°. The second sets of slots “ 27 ,” “ 30 ,” “ 39 ,” and “ 42 ” face the interior of the screen enclosure, and are oriented at δ degrees, with an exemplary value of 22.5 degrees (+/−) from the 0°/180° reference. The sets of slots “ 28 ,” “ 29 ,” “ 40 ,” and “ 41 ” for pipe 1110 are also oriented at δ degrees, with an exemplary value of 22.5 degrees (+/−) from the 0°/180° reference. That is, the difference in angle between the internally oriented slots is approximately 45° or so.
FIG. 11J is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 without a bottom pan having a six pipe configuration showing exemplary slot location angles. The six pipe configuration without the bottom pan includes similar corresponding or equivalent components as the three pipe configuration that is shown in FIG. 11I , and described above. Therefore, for the sake of brevity, clarity, convenience, and to avoid duplication, the general description of FIG. 11J will not repeat every corresponding or equivalent component that has already been described above in relation to the three pipe configuration that is shown in FIG. 11I . As illustrated, with this exemplary embodiment, each of the four interior pipes 1112 to 1118 include four sets of slots (with each set including a plurality of slots aligned along the axial length of the pipes), including slots sets “ 43 ” to “ 58 ” that are oriented at an angle δ degrees orientation, with an exemplary value 22.5 degrees from 0°/180° reference. That is, the difference in angle between the sets of slots on each pipe is approximately 45° or so.
FIG. 11K is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 without a bottom pan having a three pipe configuration (illustrated in FIG. 10B ) showing exemplary slot location angles. As illustrated, with this exemplary embodiment, a first set of slots “ 1 ” and “ 2 ” on pipes 1104 and 1102 face the exterior of the enclosure juxtaposed proximal the curved or rounded lateral edges 214 and 216 , and are oriented at an angle λ degrees orientation, with an exemplary value of about 0°/180°. The second sets of slots “ 59 ” and “ 62 ” face the interior of the screen enclosure, and are oriented also at λ degrees, with an exemplary value of about 0°/180°. The sets of slots “ 60 ” and “ 61 ” for pipe 1110 are also oriented at λ degrees, with an exemplary value of about 0°/180° reference.
FIG. 11L is an exemplary cross-sectional illustration of the aquatic extraction and filtration device 100 without a bottom pan having a six-pipe configuration showing exemplary slot location angles. The six-pipe configuration without the bottom pan includes similar corresponding or equivalent components as the three pipe configuration that is shown in FIG. 11K , and described above. Therefore, for the sake of brevity, clarity, convenience, and to avoid duplication, the general description of FIG. 11L will not repeat every corresponding or equivalent component that has already been described above in relation to the three-pipe configuration that is shown in FIG. 11K . As illustrated, with this exemplary embodiment, each of the four interior pipes 1112 to 1118 include two sets of slots (with each set including a plurality of slots aligned along the axial length of the pipes), including slots sets “ 63 ” to “ 70 ” that are oriented at an angle λ degrees orientation, with an exemplary value about 0°/180°.
Accordingly, one aspect of the invention is that it protects aquatic life from being impaled on the screening device, or ingested into the pumps, while pumping water from streams, lakes or other body of water. The internal plumbing distributes the intake flow over the entire area of the screen, balancing approach velocities and eliminating “hotspots” that could impale aquatic life. The invention's low profile enables water to be pumped from very shallow water sources, certain jurisdictional requirements state that the depth of the water must be 2 times the thickness of the device at a minimum, allowing for a buffer zone of water above the device. The lightweight, portability and small profile makes the aquatic extraction and filtration device 100 easy to use and transport. The present invention will be effective in the exploitation of most available water sources, allowing more water to be pumped, increasing the safety factor, and reducing risk to life and property. Equipment and labor expenses will be reduced as a result of the increased efficiency afforded by aquatic extraction and filtration device 100 .
Although the invention has been described in considerable detail in language specific to structural features and or method acts, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as preferred forms of implementing the claimed invention. Therefore, while exemplary illustrative embodiments of the invention have been described, numerous variations and alternative embodiments will occur to those skilled in the art. For example, the number and sizes of the various components mentioned may be varied. Increasing the size of the screen 202 will enable the use of a stronger and more powerful pumping action to extract more gallons of water per time, without an increase in the rate of flow of water impinging on the screen. The dimensions of the slots, their orientation, and their distances with respect to one another may be varied to reduce or increase the flow rates, using the same or different size screen for different applications of the filtering system. Accordingly, dimensions of any of the components mentioned may easily be varied to accommodate an increase or a decrease in the amount of water pumped per time, in view of the requirement that the flow rate of water (or “approach velocity”) impinging against the screen of the aquatic filtration device remain within a pre-set amount. Such variations and alternate embodiments are contemplated, and can be made without departing from the spirit and scope of the invention.
It should further be noted that throughout the entire disclosure, the labels such as left, right, front, back, top, bottom, forward, reverse, clockwise, counter clockwise, up, down, or other similar terms such as upper, lower, aft, fore, vertical, horizontal, proximal, distal, etc. have been used for convenience purposes only and are not intended to imply any particular fixed direction or orientation. Instead, they are used to reflect relative locations and/or directions/orientations between various portions of an object.
In addition, reference to “first,” “second,” “third,” and etc. members throughout the disclosure (and in particular, claims) is not used to show a serial or numerical limitation but instead is used to distinguish or identify the various members of the group.
In addition, any element in a claim that does not explicitly state “means for” performing a specified function, or “step for” performing a specific function, is not to be interpreted as a “means” or “step” clause as specified in 35 U.S.C. Section §112, Paragraph 6. In particular, the use of “step of,” “act of,” “operation of,” or “operational act of” in the claims herein is not intended to invoke the provisions of 35 U.S.C. §112, Paragraph 6. | An aquatic extraction and filtration device, comprising a portable frame, a screen enclosing the portable frame for blocking solids, and piping coupled within the enclosed portable frame for extracting water. The aquatic extraction and filtration device filtering and moving of water at a first flow rate by a pump, and moving the filtered water through a set of openings at a second flow rate, greater than the first flow rate by the pump. Finally, extracting water through the set of openings at a substantially equal flow rate to that of a third flow rate of water that moves through the pump. | 1 |
The present invention is directed to plastic closures, and more particularly to a closure that can be modified by a user to change the functionality of the closure. In the specific embodiment disclosed, for example, the closure can be modified by a user from child-resistant to non-child-resistant operation.
BACKGROUND AND SUMMARY OF THE INVENTION
It is a general object of the present invention to provide a plastic closure that can be modified by a user to alter its functionality or mode of operation.
A closure in accordance with one aspect of the invention includes a one-piece integrally molded plastic shell having a shell portion that is engageable within a container such that the closure is adapted to function in cooperation with the container in a first predetermined mode of operation. The shell portion is selectively removable by a user so that the closure is adapted to function in cooperation with the container in a second predetermined mode of operation different from the first mode of operation. In the disclosed embodiment of the invention the shell portion is frangibly connected to the shell and includes structure that is cooperable with the container in a child-resistant mode of operation. Removal of the shell portion by a user thus converts the closure for operation in a non-child-resistant mode of operation.
In accordance with a second aspect of the invention, there is provided a method of making a closure that is adapted to be converted by a user between first and second differing modes of operation in cooperation with a container. A one-piece integrally molded closure shell is provided with a portion frangibly connected to the shell, such as a band having child-resistance structure frangibly connected to the shell. The portion is adapted to cooperate with a container to operate in a first mode of operation—e.g., a child-resistant mode of operation—and the closure shell is adapted to cooperate with the container in a second mode of operation—e.g., a non-child-resistant mode of operation—when the portion is removed by a user.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, together with additional objects, features, advantages and aspects thereof, will be best understood from the following description, the appended claims and the accompanying drawings, in which:
FIG. 1 is a cross-sectional view of a child-resistant package according to one exemplary embodiment of the present invention;
FIG. 2 is a partial cross-sectional view of a closure of the child-resistant package of FIG. 1 ; and
FIG. 3 is an exploded partial cross-sectional view of the closure of FIG. 2 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 illustrates a child-resistant package 10 that is substantially similar to that disclosed in U.S. Pat. No. 5,899,348, except for the inventive features of the present invention, which will be described in detail below. U.S. Pat. No. 5,899,348 is assigned to the assignee hereof and is incorporated by reference herein. The child-resistant package 10 includes a cylindrical plastic vial or container 12 which has one or more surface manifestations or external threads 14 on a finish 16 , and optionally has a radial flange 18 below the threads 14 . The present invention discloses the use of threads 14 , but it is contemplated that any surface manifestations may be used, including bayonet features and the like. A child-resistant element, such as a deflectable tab or release element 20 , is formed on the container 12 , preferably at a circumferential interruption or space in the radial flange 18 . The deflectable release element 20 includes an integral cantilevered stop element or lug 22 that extends axially upwardly from the release element 20 . The cantilevered lug 22 also extends generally circumferentially in the same direction as a downward-threading spiral direction of the threads 14 , and terminates in an axial stop surface 24 . As defined herein, threading and unthreading generally corresponds to the terms applying and removing, and more specifically corresponds to the terms rotating, pulling, and the like.
Referring to FIGS. 1-3 , the child-resistant package 10 further includes a plastic closure 26 . Closure 26 in the illustrated embodiment includes a one-piece integrally molded shell having a base wall 28 and a skirt 30 with one or more internal manifestations or threads 32 . The axial edge of skirt 30 is integrally connected—i.e., as molded—to a band 38 . This integral connection is a frangible connection, such as by a frangible web or a circumferential array of frangible bridges 44 . A child-resistant element, such as a locking lug 48 , extends axially downwardly from the ledge 40 of band 38 and radially inwardly from the band skirt 42 . More than one locking lug 48 may be provided, but the quantity preferably corresponds to the quantity of threads on the container finish and closure skirt. The locking lug 48 also includes a chamfered surface 50 to facilitate application of the closure 26 to the container 12 .
Closure 26 is applied to container 12 by downwardly rotating the closure over the finish 16 of the container 12 so as to engage the threads 32 of the closure 26 with the threads 14 of the container 12 . Before the closure 26 abuts the finish 16 of the container 12 , the locking lug 48 traverses freely over the cantilevered lug 22 and deflects the cantilevered lug 22 downwardly in the process. Once the locking lug 48 has deflected and passed over the cantilevered lug 22 , the cantilevered lug 22 snaps back to its original upwardly extending orientation. Thus, if one attempts to open the child-resistant package by rotating the closure 26 in an unscrewing or upward threading direction, the locking lug 48 will confront the axial stop surface 24 of the cantilevered lug 22 and thereby prevent the closure 26 from rotating any further. Accordingly, the closure 25 will not be removable from the container 12 , unless the child-resistant feature is defeated. The child-resistant feature of the present invention may be temporarily defeated by first depressing the release element 20 with a user's thumb or finger. Depressing the release element 20 in a radially inward and axially downward direction tends to pull the cantilevered lug 22 in an axial direction out of engagement or confrontation with the locking lug 48 of the closure 25 . Once this is done, the closure 25 may be further rotated in the upward threading direction until the threads 32 of the closure 25 disengage from the threads 14 of the container 12 to remove the closure 26 and thereby open the container 12 .
There are, however, circumstances in which it may be desired permanently to defeat the child-resistant feature of the present invention, such that the child-resistant package 10 is converted to a non-child-resistant package. In other words, the child-resistant package 10 is capable of operating in two modes: a child-resistant mode as originally provided and a non-child-resistant mode as modified. The child-resistant feature may be permanently defeated by removing or separating the band 38 from the skirt 30 of the closure 26 , with the closure removed from the container, as depicted in the exploded view of FIG. 3 . After the band is removed or separated from the closure 26 , the closure 26 will function in a non-child-resistant manner. Referring to FIG. 2 , the band 38 may be separated from the skirt 30 of the closure 26 in any desired manner. For example, in one method, the band 38 may be separated by removing the closure 26 from the container 12 , gripping the base wall 28 and/or skirt 30 with one hand, gripping the band 38 with another hand, and pulling in opposite directions to break the frangible bridges 44 and thereby separate or remove the band 38 from the closure shell. Band 38 may also be severed from the shell.
There has thus been disclosed a closure, a closure and container package, and a method of manufacture that satisfy all of the objects and aims previously set forth. The present invention has been disclosed in conjunction with one exemplary embodiment thereof, and a number of modifications and variations have been discussed. Other modifications and variations will readily suggest themselves to persons of ordinary skill in the art in view of the foregoing description. For example, the invention has been disclosed in conjunction with a one-piece closure. However, additional closure elements, such as liners or other sealing elements, can be provided without departing from the disclosure. Furthermore, the invention has been disclosed in conjunction with converting a child-resistant closure to a non-child-resistant closure; however other implementations are contemplated. Indeed, the invention is intended to embrace all modifications and variations as fall within the spirit and broad scope of the appended claims. | A closure includes a one-piece integrally molded plastic shell having a shell portion that is engageable with a container such that said closure is adapted to function in cooperation with the container in a first predetermined mode of operation, such as a child-resistant mode of operation. The shell portion is selectively removable by a user such that the closure is then adapted to function in cooperation with the container in a second predetermined mode of operation different from said first mode of operation, such as a non-child-resistant mode of operation. | 1 |
This invention has to do with a novel fuel cell catholyte regenerating apparatus.
BACKGROUND OF THE INVENTION
In the art of fuel cells, there are a number of different forms of fuel cells which include adjacent anode and cathode sections separated by ion exchange membranes or barriers and which are filled with or contain volumes of anolyte and catholyte (electrolyte solutions) and in which anode and cathode plates are immersed. Still other fuel cells, of a somewhat similar nature, include ion exchange sections between and separated from the anode and cathode sections, by ion exchange barriers or membranes and which are filled with ionolyte solutions.
Effective and efficient operation of fuel cells of the general character referred to above is greatly dependent upon maintaining the electrolytes, that is, the anolytes and catholytes or the anolytes, ionolytes and catholytes in proper chemical balance. The normal fuel cell reaction in the fuel cells of the character referred to above works to adversely alter the chemical balance of the electrolytes and requires that the electrolytes be constantly monitored and regularly replaced with new or fresh electrolytes in order to maintain effective and efficient fuel cell operation.
To maintain the electrolytes in fuel cells in a properly balance condition by replacing the old or spent electrolytes with new or fresh electrolytes require that large and heavy supplies of new or fresh electrolytes be provided and maintained and requires complicated and inconvenient to operate means for effecting a replacement of spent electrolytes with fresh or new electrolytes in the fuel cells. Means must also be provided to receive and/or to effect disposal of the replaced or spent electrolytes. The whole of the apparatus or means required to effect handling new and old electrolytes in the course of operating fuel cells generally occupies more space, is heavier and can be more costly than the fuel cells served thereby. Further, the electrolytes are or can be costly to establish solutions and are such that the practice of replacing partially spent electrolytes with fresh electrolytes and directing the spent electrolytes to waste cannot be considered desirable and is certainly not a cost effective practice.
It is apparent that many prior art fuel cells have been determined to be wanting and unsuitable for practical use because they require large, heavy, costly and inconvenient to maintain and operate electrolyte supply means and/or systems, not because the fuel cells themselves are inherently wanting.
In accordance with the foregoing, there is a recognized want and need for electrolyte supply means and/or apparatus for fuel cells of the general character referred to in the preceding which eliminate the need to provide and maintain large volumes of fresh electrolytes, eliminate uneconomical waste of electrolytes and which are easy and economical to make and maintain, whereby sustained operation of such fuel cells can be made functionally and economically practical. More particularly, there is a want and need for an effecive and efficient means or apparatus for regenerating cathode electrolytes or catholytes for that class of fuel cells having cathode sections which are structurally separated from related anode sections or related ion exchange sections, whereby such fuel cells can be operated continuously and uninterruptedly on and with a small supply of catholyte.
OBJECTS AND FEATURES OF MY INVENTION
It is an object of my invention to provide a novel apparatus for maintaining the supply of catholyte in a fuel cell or in a battery of fuel cells, in balanced condition throughout protracted and sustained periods of fuel cell operation.
It is an object and a feature of my invention to provide an apparatus for the purpose set forth above related to or in combination with the cathode section or sections of one or a battery of fuel cells which apparatus receives spent or weakened and diluted catholyte, works upon the spent catholyte to rejuvenate it and to bring it back to full strength and which returns the regenerated catholyte back into the fuel cell cathode section or sections served thereby.
It is an object and feature of my invention to provide a means or apparatus of the general character referred to above which is easy and economical to make and maintain, which is easy, effective and dependable in operation, and which is sufficiently small and light so that its use, in combination with a related battery of fuel cells, is highly effective and practical in the great majority of those situations where the battery of fuel cells might be used.
The foregoing and other objects and features of my invention will be made apparent and fully understood from the following detailed description of my invention, throughout which description reference is made to the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic view of my new apparatus shown connected to and in combination with a fuel cell;
FIG. 2 sets forth the cathode fuel cell reaction formula in the preferred embodiment of my invention.
DESCRIPTION OF THE INVENTION
The fuel cell catholyte regenerating apparatus that I provide is intended to be related to and to serve a multiplicity of like fuel cells which are related to establish a battery of fuel cells. For the purpose of this disclosure and so an not to unduly complicate the drawings and possibly cloud the invention, I have elected to illustrate and will describe the apparatus related to a single fuel cell F. It is to be understood that the fuel cell F is but one of a multiplicty of like fuel cells in a related battery of fuel cells served by my apparatus.
The fuel cell F can vary considerably in form and details of construction and is diagrammatically shown as including an anode section A, a central or intermediate ion exchange section I and a cathode section C. The anode section A is filled with or contains a suitable volume of anolyte (electrolyte) 10, an anode plate 11 immersed in the anolyte and an anode terminal 12 related to the plate 11 and accessible at the exterior of the cell structure. The intermediate ion exchange section I is filled with or contains a suitable volume of ionolyte (electrolyte) 13 which is separated from the anolyte 10 by an ion exchange barrier or membrane B-1. The catholyte section C is filled with or contains a suitable volume of catholyte (electrolyte) 14 which is separated from the ionolyte 13 by an ion exchange barrier or membrane B-2. The section C further includes an electron distributor or cathode plate 15 immersed in the catholyte 13 and a cathode terminal 16 related to the plate 15 and accessible at the exterior of the cell.
The terminals 12 and 16 are connected with an electric circuit 17 served by the fuel cell F. The circuit 17 allows or provides for the flow of free electrons from the anode section A to the cathode section C. The circuit 17 is shown as including a resistance 18 which represents a work load served by the cell F and as including an on and off switch 19.
In practice, the anode plate 11 can be established of various or different materials and/or elements which are suitable and effective anode fuels. For example, and for the purpose of this disclosure, the anode plate 11 is aluminum. The anolyte 10 in the section A is an aqueous alkaline or base solution of, for example, sodium hydroxide.
The ionolyte 13 in the intermediate or central ion exchange section I can be an aqueous alkaline solution similar to the anolyte 10.
The catholyte 13, like the ionolyte, is an aqueous nitric solution. The cathode plate 15 is a chemically inert electron distributor element or part and is preferably established of particular carbon or the like having great surface area.
When the switch 19 of the electric circuit 17 is closed, electrons flow from the anode section A to the cathode section C and fuel cell reaction is commenced. Fuel cell reaction generates free electrons or electric current at the anode section A. The current flows through the circuit 17 to perform suitable work at the resistance 18 and directs free electrons into the cathode section C.
Upon the addition of free electrons (3 e - ) to the nitric acid catholyte 14 and commencement of fuel cell reaction, hydrogen ions (3 H+) move from the ion exchange section 13 through the ion exchange membrane B-2 and combine with the catholyte. The resulting chemical reaction in the cathode section reduces the nitric acid (HNO 3 ) to nitrogen oxide gases (NO and NO 2 ) and produces water (2 H 2 O). The generating of nitrogen oxide gases results in the depletion of acid in the catholyte and the water generated by fuel cell reaction dilutes the acid catholyte. Accordingly, reduction and loss of acid and the addition of water combined to rapidly weaken and dilute the catholyte to a degree that it will not support effective and efficient fuel cell reaction. When the catholyte is so weakened and/or diluted, it is said to be "spent".
In common practice, when the catholyte in a fuel cell or in a battery of fuel cells is spent, the spent catholyte is drained from the cell or cells and directed to waste. The spent and wasted catholyte is replaced with new or fresh catholyte from an available supply of new or fresh catholyte.
The fuel cell catholyte regenerating apparatus that I provide is intended and operates to receive spent catholyte 14 and the nitrogen oxide gases from the cathode section C of the fuel cell F and works upon the spent catholyte and gases to regenerate or return the materials worked upon to their original state, that is, to new or fresh catholyte. The apparatus further works to return the new or regenerated catholyte back into the fuel cell F, thus maintaining the catholyte in the fuel cell in desired strength or chemical balance at all times. Thus, the apparatus serves to eliminate the need to commit spent catholyte to waste and the need to continuously replace spent catholyte with new catholyte from an independent supply of fresh catholyte.
The apparatus that I provide includes a liquid or outlet port 20 in the fuel cell structure and communicating with the cathode section C and a gas outlet port 21 in the fuel cell structure communicating with the section C. Liquid and gas conducting lines 22 and 23 connect with the ports 20 and 21 and extend to and connect with liquid and gas inlets of a mixing unit 24. The mixing unit 24 has an outlet which is connected with a delivery line 25 extending to an absorption column 26.
A pump 27 is engaged in the line 22 to move liquid catholyte from the cell section C and to deliver into and through the mixing unit 24 at substantial velocity. The mixing unit 24 is an aspirator unit and is such that the liquid catholyte directed through it draws the gases from the cell section C through line 23 and commingles or mixes the gases with the catholyte within the flowing from the unit 24. The commingled or mixed catholyte and gases flowing from the mixing unit 24 are conducted through the lines 25 and discharge into the absorption column 26. The absorption column 26 is an elongate vertical tank-like unit with a lower chamber 27 having an upper receiving portion and a lower catch basin portion, an upper gas accumulating chamber 28, and an intermediate or central absorption chamber 29. The absorption chamber is filled with a suitable high wetted surface area packing 30. In practice, the nature and form of the packing 30 can vary widely. In the preferred carrying out of my invention, the packing 30 is established of thin, flat metal ribbons formed with a plurality of very small burred perforations. The packing 30 is contained in the chamber 29 and the interfaces between the adjacent chambers in the column are defined by suitable metal fabric screens or the like.
In addition to the foregoing, the absorption column 26 includes, contains or is provided with a volume of solvent S which occurs in and wets the surface of the packing 30. In one preferred carrying out of my invention, the solvent S is a solution of 20-50% tributyl phosphate and 80-50% kerosene. While other materials can be used to establish solvents S which are the full equivalents of the noted kerosene base solvent, the noted solvent is economical and easy to make.
The solvent S is introduced into the top of the column 26 above the packing 30 and flows down through the packing 30 to collect in the catch basin portion of the lower chamber 26', as will be made apparent in the following.
The commingled or mixed gases and spent catholyte flowing from the mixing unit 24 through line 25 and into the column 26 is discharged in the column 26 at the bottom or lower end of the packing 30 and is preferably directed upwardly into and through the packing. The gases and catholyte flowing up into and through the packing 30 counter the gravity induced downwardly flow of the solvent S therein. The solvent absorbs the gases and the gas ladened solvent, commingled with the catholyte, drops down into the catch basin portion of the lower chamber 26' in the column.
To assure complete absorption of all of the gases, a recirculating line 31 is connected with and between the upper and lower chambers 26' and 28 of the column 26 and a pump 32 is engaged in the line 31 to move gases rising and collecting in the chamber 28, at the top of the column, down and into the chamber 26' at the bottom of the column, for recirculation up into and through the packing 30.
The solvent S, with absorbed gases and the spent catholyte collected in the lower catch basin portion of the lower chamber 27 of the column 26 is conducted from the column 26 through a transfer line 33 and is commingled and mixed with air and thence delivered into the lower end of an elongate vertical tank-like catalyst column 40.
The transfer line 33 has a pump 34 engaged therein to move the materials from the column 26 to the column 40 and has an aspirator 35 engaged therein, downstream of the pump 34. The aspirator 35 has an air inlet and operates to draw air, which contains necessary oxygen (0 2 ) from the atmosphere and commingles the air or oxygen with the liquids flowing into the column 40. The commingled oxygen is, at least in part, absorbed by the solvent whereby the nitric oxide gases absorbed by the solvent and the oxygen are brought into intimate contact with each other and the nitric oxide gases are suitably oxidized by the oxygen. The aspirator 35 is adjustable and/or set so that the oxygen (0 2 ) from the air is added to the solution flowing through the aspirator in stoichiometric proportions for effective oxidation of the solvent absorbed nitric oxide gases.
The catalyst column 40 has a lower collector and separator chamber 41, an upper accumulator chamber 42, and a central or intermediate catalyst chamber 43.
The catalyst chamber 43 is filled with a suitable catalyst packing 44. The packing 44 in chamber 43 can, for example, be a hydrogen form cation exchange resin produced from a cross-linked styrene divinylbenzene polymer or can, for example, be established by a volume of alumina pellets coated with appropriate elements such as palladium, platinum, rhodium, or ruthenium. It might also be established of a suitable metal in perforated ribbon form, similar to the packing 30 in column 26. The foregoing example of catalyst packings are but examples of packing materials that might be advantageously employed.
The packing 43 is contained and the interface between the chambers 41, 42 and 43 are defined by screens or the like.
The line 33 enters the lower end portion of the column 40 and opens upwardly at the bottom of the packing 44.
The materials conducted through the line 33 and into the lower portion of the column 40 flow up through the packing 44. The absorbed nitric oxide gases are oxidized by the entrained and/or absorbed oxygen within the packing 44 to regenerate or establish nitric acid which recombines with and strengthens the acid content of the spent catholyte within the column 40. Further, the solvent and strengthened or regenerated nitric acid catholyte solution drop down into and collect in the lower chamber 41 to separate therein. That is, the regenerated catholyte and solvent settling in the lower chamber 41 separate by specific gravity displacement. The solvent rises to the top of and occurs above the catholyte and well-defined interface is established therebetween.
The other gases from the air which are introduced into the materials worked upon by the aspirator 35 and which are discharged into the column 40 separate and rise to the upper accumulator chamber 42 of the column 40 from which they are suitably vented to atmosphere.
The separated solvent S in the column 40 is conducted from the column 40 and delivered into the top of column 26 for recirculation through the packing 30 therein by means of a return line 45 connected with and between the lower portion of the column 40 and the upper portion of the column 26 and in which a pump 46 is engaged to move the solvent (substantially as shown).
The separated regenerated or fresh catholyte collected at the bottom of the chamber 41 of column 40 is conducted from the column 40 to a holding tank 50 by a flow line 47 in which a suitable pump 48 is engaged to move the liquid. The pump 48 is preferably under control of a resistance type liquid level sensing device 49 which operates to close a power supply to the pump 48 when the level of the catholyte collected at the bottom of the column 40 is of a predetermined low level. The device 49 serves to maintain the supply of catholyte suitably distributed throughout the system or apparatus at all times.
The catholyte in the holding tank 50 is gravity fed back into the cathode section C of the fuel cell F by a delivery line 51 extending from the tank through an inlet port in the fuel cell structure.
The regenerated or reconstituted catholyte delivered into the holding tank 50 from the column 40 is still diluted by the water (H 2 0) product of cathode reaction. To remove excess water from the catholyte in the holding tank 50, I provide a distillation column 60 for reconcentrating the catholyte by fractional distillation. The column 60 is a conventional plate or packed type distillation column with a liquid inlet connected with the tank 50 by a line 61, a liquid outlet connected with the tank 50 by a line 62, and a vapor outlet connected with a condensor 63 by a line 64. A pump 65 is engaged in the line 62 to move liquid from the column 60 through line 62 back into the tank 50.
In the case illustrated, a liquid heater unit H is engaged in a recirculation line 67 with upper and lower inlet and outlet ends communicating with the column 60 and a pump 68 engaged in the line 67 to move and recirculate the catholyte in the column 60 through the heater unit H. The water vapor flowing from the column 60 into the condensor 63 condenses therein and is thereafter conducted through line 69 into the ion exchange section I of the fuel cell F to maintain the supply of ionolyte therein at desired level and to maintain it suitably diluted.
The fractional distillation process if preferably carried on slowly and continuously. The catholyte in the holding tank 50 is continuously recirculated through the column 60 and is reconcentrated at approximately the same mean rate that reconstituted catholyte is conducted from the tank 50 into the fuel cell F.
In practice, the diluted reconstituted catholyte flowing from the catalyst column 40 can be conducted directly to the distillation column 60 rather than to the tank 50, without departing from the broader aspects and spirit of my invention.
With the apparatus described above and shown in FIG. 1 of the drawings, and with the catholyte in the cathode section of the fuel cell being an aqueous solution of nitric acid (HNO) to which three free electrons (3 e - ) from the anode section A of the fuel cell and three hydrogen ions (3 H+) from the ion exchange section I of the fuel cell are added, the chemical reaction at the cathode section C of the cell F, that is, the cathode reaction is that reaction which is set forth in the formula in FIG. 2 of the drawings.
In practice, when the materials employed to establish the anode plate and the various electrolytes of the fuel cell F are changed, the cathode chemical reaction, while similar to the reaction shown in FIG. 2 of the drawings, will change. Accordingly, the cathode chemical reaction set forth in claim 2 of the drawings is but an example of the cathode reaction which is encountered in connection with and in carrying out of my invention and is set forth to provide a better understanding of the nature and function of my new apparatus.
In the drawings, the lines 22, 23, 51 and 69 are shown as having manifolds 60, 61, 62 and 63 engaged therein. The manifolds serve to connect the apparatus with a plurality of like fuel cells which make up a battery of fuel cells served by the apparatus.
Further, in practice, the lines 22, 23, 51 and 69 are preferably established of dielectric plastic tubing and are sufficiently small in diameter and sufficiently long so that the electric resistance of the columns of liquid and gas therein is sufficiently great to prevent the flow of shunt currents therethrough which might adversely affect operation of the battery of cells. The foregoing method and/or means for electrically isolating the cells from the apparatus is but one of a number of means that can be advantageously used. The means shown is preferred since it is quite inexpensive, simple and has proven to be highly effective.
Having described one preferred form and carrying out of my invention, I do not wish to be limited to the specific details herein set forth but wish to reserve to myself any modifications and variations that might appear to those skilled in the art and which fall within the scope of the following claims: | A catholyte regenerating apparatus for a fuel cell having a cathode section containing a catholyte solution and wherein fuel cell reaction reduces the catholyte to gas and water. The apparatus includes means to conduct partially reduced water diluted catholyte from the fuel cell and means to conduct the gas from the fuel cell to a mixing means. An absorption tower containing a volume of gas absorbing liquid solvent receives the mixed together gas and diluted catholyte from the mixing means within the absorption column, the gas is absorbed by the solvent and the gas ladened solvent and diluted catholyte are commingled. A liquid transfer means conducts gas ladened commingled solvent and electrolyte from the absorption column to an air supply means wherein air is added and commingled therewith and a stoichiometric volume of oxygen from the air is absorbed thereby. A second liquid transfer means conducts the gas ladened commingled solvent and diluted catholyte into a catalyst column wherein the oxygen and gas react to reconstitute the catholyte from which the gas was generated and wherein the reconstituted diluted catholyte is separated from the solvent. Recirculating means conducts the solvent from the catalyst column back into the absorption column and liquid conducting means conducts the reconstituted catholyte to a holding tank preparatory for recirculation through the cathode section of the fuel cell. | 8 |
BACKGROUND OF INVENTION
As shown in FIG. 1 , a common computer system ( 100 ) includes a central processing unit (CPU) ( 102 ), memory ( 104 ), and numerous other elements and functionalities typical of today's computers (not shown). The computer ( 100 ) may also include input means, such as a keyboard ( 106 ), a mouse ( 108 ), and an output device, such as a monitor ( 110 ). Those skilled in the art will understand that these input and output means may take other forms in an accessible environment. In one or more embodiments of the invention, the computer system may have multiple processors and may be configured to handle multiple tasks.
The CPU ( 102 ) is an integrated circuit (IC) and is one of many integrated circuits included in the computer ( 100 ). Integrated circuits may perform operations on data and transmit resulting data to other integrated circuits. The performance of the computer depends heavily on the speed and efficiency with which data is transmitted between integrated circuits.
FIG. 2 shows a block diagram of a prior art system ( 200 ) for transmitting data from a transmitting IC ( 202 ) to a receiving IC ( 250 ) using a transmission path ( 248 ). A data source ( 210 ) represents computing elements of the transmitting IC ( 202 ). The data source ( 210 ) may produce data for the transmitting IC ( 202 ) to transmit to the receiving IC ( 250 ). Data to be transmitted is sent by the data source ( 210 ) to the transmitting output buffer ( 212 ) to be put onto the transmission path ( 248 ). The transmission path ( 248 ) propagates the data signal to the receiving IC ( 250 ) where the data signal is received at the data destination ( 262 ), which represents the receiving IC's ( 250 ) input buffer and computing elements.
The rate of data transmission on the transmission path ( 248 ) between the transmitting IC ( 202 ) and the receiving IC ( 250 ) on a printed circuit board (PCB) is limited by a bandwidth of the transmission path ( 248 ). However, the rate at which data can be put onto the transmission path ( 248 ) is limited by the speed at which output buffer ( 212 ) on the transmitting IC ( 202 ) can operate. Using current technologies, the rate at which data can be put onto the transmission path ( 248 ) may be substantially lower than the rate at which the transmission path ( 248 ) may transmit.
If the output buffer ( 212 ) is incapable of using the entire bandwidth of the transmission path ( 248 ), then part of the bandwidth of the transmission path ( 248 ) is wasted. In order to transmit more data, more transmission paths (like 248 ) must be used. Additional transmission paths result in increased cost of materials and increased design complexity. Each of the added transmission paths must also use a package pin to drive the data signals on those transmission paths, increasing complexity and cost still more.
Printed circuit boards are commonly constructed from a glass fiber epoxy laminate called FR4. Transmission paths are traces of metal on the PCB. The traces of metal form wires along which electrical signals may be propagated. The traces of metal are commonly constructed from copper. One of ordinary skill in the art will understand that materials other than FR4 may be used for the PCB and that materials other than copper may be used for the metal traces. Properties of the metal traces and of the PCB material determine the bandwidth of the transmission path formed by the metal traces on the PCB. A significant property of the metal traces is resistivity, which, along with geometry, determines the resistance of the traces. A significant property of the PCB material is the dielectric constant, which, along with geometry, determines the capacitance between metal traces.
A PCB may connect to another PCB through a PCB connector. A PCB connector may include multiple conductive elements to connect multiple metal traces on a first PCB to multiple metal traces on a second PCB. A transmission path may traverse a metal trace on a first PCB, a PCB connector, and a metal trace on a second PCB.
SUMMARY OF INVENTION
According to an embodiment of the present invention, a computer system having a printed circuit board comprises a transmission path disposed on the printed circuit board; a first transmitter, disposed on the printed circuit board, arranged to output a first modulated signal; a second transmitter, disposed on the printed circuit board, arranged to output a second modulated signal on the transmission path, where a modulated transmission on the transmission path comprises the first modulated signal and the second modulated signal; a first receiver, disposed on the printed circuit board, arranged to receive the modulated transmission; and a second receiver, disposed on the printed circuit board, arranged to receive the modulated transmission.
According to an embodiment of the present invention, a method for transmitting on a transmission path on a printed circuit board comprises generating a first modulated signal using a first carrier frequency, where the first carrier frequency is within a first frequency band of a plurality of frequency bands; generating a second modulated signal using a second carrier frequency, where the second carrier frequency is within a second frequency band of the plurality of frequency bands; transmitting a modulated transmission on the transmission path on the printed circuit board, where the modulated transmission comprises the first modulated signal and the second modulated signal; and receiving the modulated transmission.
According to an embodiment of the present invention, an apparatus comprises means for generating a first modulated signal using a first carrier frequency, where the first carrier frequency is within a first frequency band of a plurality of frequency bands; means for generating a second modulated signal using a second carrier frequency, where the second carrier frequency is within a second frequency band of the plurality of frequency; means for transmitting a modulated transmission on the a transmission path on a printed circuit board, where the modulated transmission comprises the first modulated signal and the second modulated signal; and means for receiving the modulated transmission.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows a prior art block diagram of a computer system.
FIG. 2 shows a block diagram of a prior art scheme for data transmission between two integrated circuits.
FIG. 3 shows a block diagram of a scheme for data transmission between two integrated circuits in accordance with an embodiment of the present invention.
FIG. 4 shows a block diagram of a scheme for data transmission between two integrated circuits in accordance with an embodiment of the present invention.
FIG. 5 shows a block diagram of a transmitter in accordance with an embodiment of the present invention.
FIG. 6 shows a block diagram of a receiver in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
A transmission path on a PCB is capable of handling more data than conventional transmitters can provide. A technique to allow multiple transmitters to transmit on the same transmission path may increase the amount of data on the transmission path. Embodiments of the present invention relate to a means for increasing data transmitted on a transmission path using modulation techniques to allow multiple data signals to be propagated on the transmission path simultaneously.
FIG. 3 shows an exemplary block diagram of a multiple band transmission system ( 300 ) in accordance with an embodiment of the present invention. In FIG. 3 , a data source ( 310 ) represents the computing elements of a transmitting IC ( 302 ). The data source ( 310 ) produces data for the transmitting IC ( 302 ) to transmit to a receiving IC ( 350 ). Rather than sending data to be transmitted to a transmitting output buffer ( 212 shown in FIG. 2 ), the data is split up into multiple data signals and sent to multiple data buffers ( 312 , 314 , 316 ). The splitting of the data into separate data signals may take multiple forms. The data source ( 310 ) comprises elements that handle this splitting.
The data source ( 310 ) may comprise multiple elements, each with data to be transmitted to the receiving IC ( 350 ). The multiple elements may be coupled to individual data buffers ( 312 , 314 , 316 ). Alternatively, the computing elements comprising the data source ( 310 ) may produce a single data signal. The single data signal may be split into multiple parallel data signals at lower speeds than the single data signal. Each of the parallel data signals may be coupled to individual data buffers ( 312 , 314 , 316 ).
Each transmitter ( 322 , 324 , 326 ) comprises a modulator. The modulator modulates the data signal forwarded from the data buffers ( 312 , 314 , 316 ) so that an appropriately configured demodulator may recover the data signal from a transmission path ( 348 ) carrying other data signals. Each transmitter ( 322 , 324 , 326 ) may modulate the signal received from the corresponding data buffer ( 312 , 314 , 316 ) such that the modulated signal produced by the transmitter (e.g., 322 ) does not interfere with the modulated signals produced by the other transmitters (e.g., 324 , 326 ).
Each of the modulated signals are put onto the same transmission path ( 348 ). A modulated transmission comprises the sum of all the modulated signals. The modulated transmission is carried by the transmission path ( 348 ). The modulated transmission is fed in parallel to a plurality of receivers ( 352 , 354 , 356 ) on the receiving IC ( 350 ). Each of the plurality of receivers ( 352 , 354 , 356 ) includes a demodulator. Each demodulator is configured to demodulate at least one of the modulated signals produced by the transmitters ( 312 , 314 , 316 ). Each demodulated output of the receivers ( 352 , 354 , 356 ) corresponds to one of the data signals produced by the data source ( 310 ). The demodulated outputs of the receivers ( 352 , 354 , 356 ) are then fed to a data destination ( 362 ). The data destination ( 362 ) is representative of the receiving IC's ( 350 ) computing elements.
One of ordinary skill in the art will understand that with a modulating transmission scheme, multiple integrated circuits may transmit and receive on the same transmission path.
FIG. 4 shows an exemplary block diagram of communication system ( 400 ) with multiple transmitting integrated circuits ( 402 , 403 ). Transmitting IC ( 402 ) includes data source ( 410 ), data buffer ( 414 ), and transmitter ( 424 ). Transmitting IC ( 403 ) includes data source ( 411 ), data buffer ( 415 ), and transmitter ( 425 ). The data source ( 410 ), data buffer ( 414 ), and transmitter ( 424 ) operate similarly to the data source ( 310 ), data buffer ( 312 ), and transmitter ( 322 ) shown in FIG. 3 . With properly configured modulators inside transmitters ( 424 , 425 ), transmitting IC ( 402 ) and transmitting IC ( 403 ) may transmit simultaneously on transmission path ( 448 ). Inside the receiving IC ( 450 ), receivers ( 452 , 456 ) demodulate the modulated signals transmitted by the transmitting integrated circuits ( 402 , 403 ) to generate demodulated data signals. The demodulated data signals are forwarded to the data destination ( 462 ), which represents the computing elements of the receiving IC ( 450 ).
One of ordinary skill in the art will understand that there are a large number of possible permutations of configurations of multiple modulating transmitters and multiple demodulating receivers using a single transmission line. FIGS. 3 and 4 are examples of only two potential configurations in accordance with embodiments of the present invention.
In one or more embodiments of the present invention, amplitude modulation may be used to modulate data signals for transmission on a transmission pathway. In an amplitude modulation system, total bandwidth of a transmission path is divided into frequency bands. Each frequency band is used to transmit one modulated signal. In one or more embodiments, each modulated signal has a bandwidth equal to or less than the bandwidth of the frequency band in which the modulated signal is transmitted. In one or more embodiments, the frequency band used by a modulated signal is determined by a carrier frequency. The carrier frequency may be equal to a center frequency of the frequency band.
FIG. 5 shows an exemplary embodiment of a transmitter ( 500 ) used for modulating a data signal. The transmitter ( 500 ) is similar to the transmitters in FIGS. 3 and 4 , for example, transmitter ( 322 ) shown in FIG. 3 . The transmitter ( 500 ) uses an amplitude modulation scheme and includes a carrier frequency oscillator ( 502 ) and a modulator ( 504 ). A data signal is carried to the modulator ( 504 ) on line ( 506 ). An output of the carrier frequency oscillator ( 502 ) is a carrier signal oscillating at the carrier frequency. The carrier signal is input to the modulator ( 504 ). The modulator ( 504 ) is a non-linear circuit that outputs a modulated signal on line ( 508 ). The modulated signal oscillates at the carrier frequency and the data signal is represented by a varying amplitude of the modulated signal.
FIG. 6 shows an exemplary embodiment of a receiver ( 600 ) used for demodulating signals modulated by a transmitter (e.g. transmitter ( 500 ) shown in FIG. 5 ). The receiver ( 600 ) is similar to the receivers in FIGS. 3 and 4 , for example, receiver ( 352 ) shown in FIG. 3 . The receiver ( 600 ) includes a local oscillator ( 602 ), a mixer ( 604 ), and a low-pass filter ( 606 ). A modulated transmission is input to the mixer ( 604 ) on line ( 610 ). An output of the local oscillator ( 602 ) is a local oscillator signal oscillating at the local oscillating frequency. In one or more embodiments, the local oscillator frequency is similar to a carrier frequency used to modulate the data signal.
The local oscillator signal is input to the mixer ( 604 ). The mixer ( 604 ) is a non-linear circuit that produces a mixer output signal that includes intermodulation frequencies and harmonic frequencies of the carrier frequency and the local oscillator frequency. One of the intermodulation frequencies produced is equal to the difference between the carrier frequency and the local oscillator frequency. If the carrier frequency and the local oscillator frequency closely match one another, the difference between them is approximately zero. Therefore, a low-pass filter ( 606 ) may be applied to the mixer output signal to filter other (non-zero) intermodulation and harmonic frequencies. The output of the low-pass filter ( 606 ) is a demodulated data signal and may be similar to a data signal originally input to a transmitter.
One of ordinary skill in the art will understand that other modulation and demodulation schemes may be used in the present invention. A more complex scheme of AM modulation includes using a local oscillator frequency that is substantially different than the carrier frequency. An output of a mixer using the more complex scheme is an amplitude modulated signal at an intermediate frequency. The amplitude modulated signal is then demodulated from the intermediate frequency. In one or more embodiments, a demodulation scheme using an intermediate frequency may decrease the complexity of a receiver. Other modulation/demodulation schemes that may be used include, but are not limited to: frequency modulation, time division multiple access, code division multiple access, and quadrature amplitude modulation.
Advantages of the present invention may include one or more of the following. In one or more embodiments, the present invention may increase the amount of data on a transmission path. In one or more embodiments, the present invention may decrease the cost of PCB manufacture by decreasing the number of traces on the PCB. In one or more embodiments, the present invention may decrease the cost of PCB manufacture by decreasing the complexity of routing signals on the PCB. In one or more embodiments, the present invention may decrease the time required to design a PCB by decreasing the complexity of routing signals on the PCB.
While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. | The present invention is an apparatus and method for increasing the amount of data on a transmission path on a printed circuit board. Conventional methods allow only one data signal to be transmitted on the transmission path. The present invention uses multiple transmitters to modulate multiple data signals to form multiple modulated signals. The modulated signals are transmitted, possibly simultaneously, on the transmission path to receivers configured to demodulate individual modulated signals and recover the original data signals. | 7 |
CROSS-REFERENCE TO RELATED PATENT
This invention is an improvement to the invention to which application Ser. No. 541,143, filed Oct. 10, 1983 is directed, which issued as U.S. Pat. No. 4,524,095 on June 18, 1985.
BACKGROUND OF THE INVENTION
The present invention is related to flat laminate parts consisting of a substrate and a cover layer with an auxiliary pull-off means for said cover layer or parts thereof.
It is often necessary to protect one or both surfaces of a flat substrate or one or both open surfaces of a flat laminate, by a cover layer before the final use thereof. Such a cover layer is necessary for instance due to the adhesive properties of said surface or its sensitivity to mechanical damage or in order to avoid evaporation of highly volatile components from a layer by way of such a surface. The cover layer in general is kept to the substrate layer by adhesive additions to said substrate layer or by the self-adhesive properties of the surface of the substrate layer which adhesive forces may be overcome by the application of mechanical pull-off forces. The problem with such compositions is to make the combination of the substrate layer and the cover layer such that both layers are securely held together but the pull-off of the cover layer or of parts thereof is easy and readily possible.
There are known already several propositions to solve this problem. Thus, a mere tearing of the laminate allows to use the finger nail to grasp a part of the cover layer and pull it off from the substrate layer and by using this part of the cover layer as grasp part to thereby allow a complete pull-off of the cover layer. It is furthermore known to compose the cover layer of several parts with a total surface larger than the surface of the substrate layer thereby producing overlapping parts in the surface of the cover layer which overlapping parts are used as grasp parts and auxiliary pull-off means in the cover layer. If no such overlapping parts are provided in the cover layer, grasp parts in the cover layer are known to be produced by sharply bending the laminate at one or several of its edges thereby causing the cover layer to be solved from the substrate layer at such edges if the cover layer is rigid enough to produce sufficient peel-off forces by such rigidity. Another known possibility to produce grasp parts for the cover layer is to cover the substrate layer by a cover layer larger than the substrate layer. Furthermore, another known means to ease the pull-off of the cover layer from the substrate layer is to produce linear cuts or preset linear breaking lines in the cover layer allowing to produce lines in the cover layer by pulling and bending the laminate wherefrom the pull-off of the cover layer may be started. Still furthermore, it is known to incorporate into the laminate a wire or a strap between the cover layer and the substrate layer said wire or strap projecting over the edges of the laminate which wire or strap serves as an auxiliary pull-off means for the cover layer from the substrate layer. It is furthermore known a flat laminate part consisting of a substrate layer and a cover layer the adhesive forces between said substrate layer and said cover layer being such that both layers are securely held together, but a pull-off of said cover layer is readily possible by hand or mechanically, said flat laminate part having additionally an auxiliary pull-off means to so pull-off said cover layer or parts of said cover layer by hand or mechanically said auxiliary pull-off means comprising preset cuts or breaking lines in the cover layer, wherein said preset cuts or preset breaking lines in said cover layer are positioned and formed such that there is at least one part of the cover layer which can be grasped per each part of said cover layer to be pulled off, said grasp part getting exposed by bending the flat laminate part to form a concave curvature of the surface of said cover layer opposite to the surface of said cover layer adhearing to said substrate layer, the at least two points of attack of the force producing such bending of the flat laminate part being distributed over the surface of the flat laminate part such that the forces acting substantially vertically from the laminate in the bend, result in a peeling off of said grasp part of said cover layer.
All these proposals to solve the problem are not satisfactory because they either necessitate additional material or complicated procedures to produce them or only give a sufficient large grasp part to easily pull-off the cover layer from the adhearing substrate layer if there is a sufficient difference in the stiffness of the cover layer and of the substrate layer.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an auxiliary pull-off means for the cover layer or parts thereof in such flat laminate parts which avoid the above mentioned disadvantages.
According to the present invention the solution of this object is a flat laminate part consisting of a substrate layer and a cover layer, the adhesive forces between the substrate layer and the cover layer being such that both the substrate layer and the cover layer are securely held together, but a pull-off of the cover layer from the substrate layer is readily possible, said flat laminate having an auxiliary pull-off means to so pull-off the cover layer or parts thereof along preset cuts or preset breaking lines in the cover layer, the preset cuts or preset breaking lines being particularly positioned and formed such that there is at least one part of the cover layer which can be grasped, for each part of the cover layer to be pulled off, which part is getting exposed by bending the flat laminate part to form a concave curvature of the surface of the cover layer opposite to the surface of the cover layer adhearing to the substrate layer with the at least two points of attack of the force producing such bending of the flat laminate part being distributed over the surface of the flat laminate part such that the mechanical forces acting substantially vertically to the laminate result in a peeling off of the grasp parts of the cover layer characterized in that there is provided a stiffened area surrounding said preset cuts or preset breaking lines to ease the peeling off of said grasp parts from said cover layer to pull-off said cover layer or parts thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is further illustrated by means of the attached drawings without however limiting the same thereto.
FIG. 1 shows a top view of the cover layer of a quadrangular part of the flat laminate according to the present invention.
FIG. 2 shows a perspective view of the bent laminate part of FIG. 1.
FIGS. 3 to 6 show the top view of the cover layers of other embodiments of the flat laminate part according to the present invention.
DETAILED DESCRIPTION
In FIG. 1, (1) is the quadrangular laminate part as such. The cover layer of this laminate part is subdivided by the preset cut or preset breaking line (4) into two partial surface areas (2) and (3). The preset cut or preset breaking line (4) runs from one edge of the laminate part to the opposite edge thereof and partially has the form of a sinusoid (sine curve). This sine curve defines the hatched or shaded surface area (6) as grasp or pick-up part for the partial surface area (2) of the cover layer and the hatched area (7) as grasp part of the partial surface area (3) of the cover layer. The stiffened area (6a) on the part (2) and an equal area on the part (3) cover the whole area of breaking line (4) and is somewhat larger. The crosses (5) characterize those areas, wherein the forces producing the bending of the laminate and thereby producing the exposition of the grasp parts (6) and (7), are to be applied. Or, the laminate is bent substantially along a line connecting the end points of line (4) at the opposite edges of the laminate to produce the peel-off of the grasp parts (6) and (7). A perspective illustration of the bent quadrangular laminate part is given in FIG. 2. The numbers contained therein have the same meaning as in FIG. 1. The exposed grasp parts (6) and (7) are readily recognizable and show that the pull-off of the surface areas (2) and (3) by hand or mechanically is readily possible.
FIG. 3 shows an oval-shaped embodiment (8) of a laminate part according to the present invention. The cover layer thereof is subdivided asymmetrically by a preset cut or preset breaking line (11) in the partial surface areas (9) and (10) different in surface area from each other. The preset cut or preset breaking line (11) connects two opposite points at the edge of the oval and is zigzag formed and produces the hatched surface area (12) as grasp part for the partial surface area (9) and the hatched area (13) as grasp part for the partial surface area (10). The zigzag form actually shown in FIG. 3 may of course also be a mirror inversion which is true for many preset cut or, respectively, preset breaking line embodiments shown in the present Figures. If bending forces in FIG. 3 attack in the area defined with crosses (5), the grasp parts (12) and (13) are exposed and the partial or complete pull-off of the cover layer is readily possible.
A triangular-shaped embodiment (14) of the laminate part according to the present invention is shown in FIG. 4. In this embodiment the present cut or, respectively, breaking line (17) runs from one edge of the triangular to one of the other edges thus subdividing the surface of the cover layer into the partial surface areas (15) and (16) different in surface size. The grasp parts (18) and (19) of this embodiment have a rectangular shape and become exposed upon the application of bending forces in the areas (5). The partial or complete pull-off of the cover layer may then occur by hand or mechanically.
A further embodiment of the present invention is shown in FIG. 5. In this embodiment two preset cuts or breaking lines subdivide the surface of the cover layer of the laminate part (20) in three partial surface areas (21), (22) and (23). The preset cuts or breaking lines run from one of the longer edges of the rectangular shape to the other long side. The preset cuts or preset breaking lines are shaped angled such that the triangular grasp part (26) for the one outer surface area part (21), the triangular grasp part (27) for the middle partial area (22) and the grasp part (28) for the other outer partial surface area (23) is formed. The exposition of these grasp parts occurs after allowing bending forces to attack in the areas indicated with crosses (5). The exposed grasp parts (26), (27) and (28) readily allow the partial or complete pull-off of the cover layer.
The circular or round embodiment (29) of the laminate part according to the present invention as shown in FIG. 6 has the particularity that the preset cut or preset breaking line (32) is a closed line, has the geometrical form substantially of an equilateral square and does not touch any edge of this embodiment of the laminate part. In order to pull off that partial surface area (31) embraced by the preset cut or breaking line partially from the cover layer allowing the partial surface area (31) to leave the partial surface area (30), the preset substantially equilaterally quadrangular cut or breaking line has two convexities at two opposite edges of the equilateral square projecting into the partial surface areas (30). These convexities (33) represent the grasp parts and may be exposed by the application of bending forces in the areas (5). The partial surface area (31) has two grasp parts (33) and thereby may be readily pulled off.
The Examples illustrated in the present drawings indicate that the present invention may have many various embodiments and is only limited by the definitions given in the following claims. Thus, a prerequisite of the present invention is that the cover layer is subdivided by the preset cuts or preset breaking lines in at least two partial surface areas. The preset cuts or breaking lines connect two points at the edge of the laminate part or form closed geometrical figures which do not touch any edge of the laminate part. The latter embodiment is in particular useful in connection with the pull-off of partial surface areas positioned within the total surface area.
The cover layer and/or the substrate layer may be composed of one or a multitude of individual layers. In all cases where there are particular circumstances, which prevent that the difference in the stiffness of the cover layer and that of the substrate layer is not sufficiently large in order to peel off the grasp part by bending the flat laminate part the area with increased stiffness in the surrounding of the preset cuts or preset breaking lines in accordance with the present invention gives a solution of the problem. The area of increased stiffness is flat in itself, having a thickness of 30 to 150 μm and its form depends upon the form of the preset cuts or preset breaking lines. They have to cover at least the area of the preset cut or preset breaking line (see the present Figures).
The stiffened area may be produced by known methods. Thus, it may be produced by a liquid, dissolved or emulgated phase directly upon the cover layer before the formation of the preset cut or preset breaking line. More particularly, the stiffened area may be produced immediately on the cover layer by cooling a liquid substrate layer. Another technique is evaporating the solvent of a dissolved substrate. Yet another technique is evaporation of the emulsifying solvent of an emulgated substrate.
Another preferred method consists in producing the area of of higher stiffness by applying another layer in the form of single-sided adhesive material of necessary thickness. Also in this embodiment, the preset cuts or preset breaking lines are produced after such material has been applied.
The partial or complete pull-off of the cover layer rendered possible by the present invention exposes the second surface of the substrate or a part thereof such that it may be used for the subsequent purpose of use of the substrate. In a preferred embodiment of the present invention, this surface of the substrate is self-adhesive such that the substrate or parts thereof, after removal of the cover layer, may be fixed to an intended base. The outer edge or contour of the laminate part may be varied and depends upon the necessities of the intended use thereof. The substrate may also have a cover layer on both of its surfaces. In accordance with the present invention, in this embodiment there may be provided preset cuts or preset breaking lines in both cover layers which allows the removal of one or both cover layers simultaneously or at different times.
The preset cuts or preset breaking lines in the cover layer may be produced by methods known to the expert in the art, for instance by punching, cutting, pressing, squeezing, or stamping while the preset beaking lines are preferably produced by perforation, local chemical treatment or by the application of pull-off wires. | The present invention is related to a flat laminate part consisting of a substrate layer and a cover layer having an auxiliary pull-off means to so pull-off said cover layer or parts of said cover layer said auxiliary pull-off means comprising a preset cut or cuts or a preset breaking line or lines in said cover layer, said auxiliary pull-off means being improved by having a stiffened area in the surrounding of the preset cuts or preset breaking lines in order to facilitate the producing of the grasp parts for pulling off said cover layer or parts of said cover layer. | 8 |
FIELD OF INVENTION
The present invention relates to a thin film resistive heater and more particularly to a circuit and method for controlling the temperature of a thin film resistive heater used to heat a liquid crystal display.
BACKGROUND OF INVENTION
FIG. 1 shows an exploded view of a conventional module 10 which is used for housing a Liquid Crystal Display (LCD) 14 . The module 10 includes a front frame 12 , an LCD 14 , a thin film resistive heater 16 , and a back frame 18 . The device 10 is held together by interlocking tabs and recesses.
As is known in the art, if the temperature of the LCD 14 becomes too cold, the liquid crystal material within the LCD 14 becomes increasingly viscous. If such a result occurs, the LCD 14 does not work properly.
In view of this problem, the thin film resistive heater 16 is provided to maintain the temperature of the LCD 14 within a certain temperature range. To perform its heating function, the thin film resistive heater 16 includes a glass substrate 20 which contains a thin film coating of, for example, indium tin oxide (ITO). The substrate 20 is attached to a plastic frame 22 . As is known in the art, when a current is passed through the thin film coating, heat is transferred to the glass substrate 20 thus creating a heater.
When the module 10 is assembled, glass substrate 20 of the thin film heater 16 is placed in thermal contact with the LCD 14 . This configuration allows for the transfer of heat from the heater 16 to the LCD 14 .
Typically, a thermistor 24 is placed on an outer edge of the glass substrate 20 to monitor the temperature of the thin film heater 16 . As is known in the art, the thermistor is a device whose resistance is a function of temperature.
Based on the design of the device shown in FIG. 1, the thermistor 24 is required to be placed on an outer edge of the thin film heater 16 to ensure that the thermistor 24 does not interrupt the viewing area of the LCD 14 . In particular, if the thermistor 24 is positioned at the center of the glass substrate 20 , a shadow will appear on the LCD 14 . This is obviously undesirable given that such a shadow would impact the usefulness and desirability of the LCD 14 .
FIG. 2 shows a conventional circuit that is used to control and measure the temperature of the thin film heater 16 shown in FIG. 1 . The circuit shown in FIG. 2 contains a power supply 26 which provides a supply voltage V SUPP to bus bars 21 of the glass substrate 20 contained within the thin film heater 16 . As is known in the art, the application of the voltage V SUPP creates a current I which in turn heats the substrate 20 .
The circuit shown in FIG. 2 also contains a temperature feedback circuit 28 which is connected to the power supply 26 and the thermistor 24 . The temperature feed back circuit 28 continuously measures the temperature of the thermistor 24 .
If the temperature of the thermistor 24 falls below a certain temperature To , the feedback circuit 28 instructs the power supply 26 to apply the voltage V SUPP to the bus bars 21 to heat the glass substrate 20 . Conversely, if the temperature of the thermistor 24 reaches temperature To, the feedback circuit 24 then instructs the power supply 26 to remove the voltage V SUPP .
While the conventional device discussed above and shown in FIGS. 1 and 2 allows for the temperature of the thermistor 24 to be measured, the device still has significant drawbacks. In particular, the design of the device shown in FIGS. 1 and 2 results in a large thermal mass at the edge of the thin film heater 16 where the thermistor 24 is located. As is known in the art, large thermal masses resist changes in temperature. That is, large thermal masses either maintain temperature for prolonged periods of time or require an inordinately large amount of heat to achieve an increase in temperature.
Given that the edge of the thin film heater 16 is in contact with a large thermal mass and that the thermistor 24 is required to be positioned at this location, it is difficult to accurately monitor and maintain the temperature of thin film heater 16 . In view of this problem, there currently exists a need for a device which can accurately measure the temperature of the center of a thin film heater in a manner that is minimally impacted by the thermal mass proximate to the heater and does not affect, in any way, the viewing area of the heater.
SUMMARY OF THE INVENTION
It is accordingly an object of the present invention to provide a device which can accurately measure the temperature of a thin film heater which is minimally impacted by a surrounding thermal mass.
It is another object of the invention to provide a device which can accurately measure the temperature of a thin film heater that does not, in any way, impact the viewing are of the thin film heater.
In accordance with the invention, a device and method are disclosed which regulate the temperature of a thin film heating element by using a modeling technique which assumes that the thin film coating of the heater functions as a single electrical resistor.
In accordance with one embodiment of the invention, a circuit for controlling the temperature of a heating device is disclosed where the circuit comprises: a heater containing a thin film coating; and a control circuit for applying a voltage to the heater; wherein the control circuit regulates the temperature of the heater by using a modeling technique which assumes that the thin film coating functions as a single resistor.
In accordance with another aspect of this embodiment of the invention, the control circuit includes: a power supply for applying a voltage to the heater; a resistor that is connected in series with the power supply and the heater; a voltage sensing device which measures voltage drops occurring across the resistor; and, a temperature control circuit which monitors the voltage sensing means and the power supply to regulate the temperature of the heater.
In accordance with another aspect of this embodiment of the invention, the temperature control circuit regulates the temperature of the heater by: (i) calculating the resistance of the thin film coating and,(ii) calculating the temperature of the thin film coating based on the calculated resistance.
In accordance with yet another aspect of this embodiment of the invention, the resistance of the thin film coating is calculated by using the equation R 2 =R 1 (V SUPP /V 1 −1).
In accordance with even yet another aspect of this embodiment of the invention, the temperature of the thin film coating is calculated by using the equation T 2 =T 0 +(R 2 −R 0 )/a.
In accordance with another embodiment of the invention, a method for calculating the temperature of a heater containing a thin film coating is disclosed, where the method comprises the steps of: (i) calculating a resistance of the thin film coating, and, (ii) calculating a temperature of the thin film coating based on the resistance calculated in step (i).
In accordance with another aspect of this embodiment of the invention, the resistance of the thin film coating is calculated by using the equation R 2 =R 1 (V SUPP /V 1 −1).
In accordance with still another aspect of this embodiment of the invention, the temperature of the thin film coating is calculated by using the equation T 2 =T 0 +(R 2 −R 0 )/a. dr
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings are included to provide an understanding of the invention and constitute a part of the specification.
FIG. 1 illustrates an exploded view of a conventional module which is used for housing an LCD;
FIG. 2 illustrates a conventional circuit which is used to control and measure the temperature of a thin film heater shown in FIG. 1; and,
FIG. 3 is a schematic representation of an illustrative embodiment of the present invention that is used to control and measure the temperature of a thin film heater.
DESCRIPTION OF THE INVENTION
FIG. 3 shows a circuit 40 in accordance with the present invention. The circuit 40 is used to control and measure the temperature of a thin film heater containing a glass substrate with a thin film coating.
The circuit 40 contains a power supply 42 and resistor R 1 . Both devices are connected in series to bus bars 21 of the glass substrate 20 . Power supply 42 provides a supply voltage V SUPP to bus bars 21 of the substrate 20 to produce a current I though the thin film coating. The current I in turn heats the substrate 20 .
The circuit 40 also includes a voltmeter 44 and a temperature control circuit 46 . The voltmeter 44 is used to measure voltage drops which occur across resistor R 1 . The temperature control circuit 46 is used to control both the power supply 42 and voltmeter 44 .
The circuit 40 , unlike the conventional device described above, does not require the use of a thermistor to measure the temperature of the edge of the substrate 20 . The circuit 40 developed in accordance with the present invention overcomes this problem by assuming, that the thin film coating on the lass substrate 20 constitutes a resistor R 2 . Based on this assumption, the circuit 40 uses a mathematical modeling, technique to calculate the temperature T 2 of the thin film coating, and substrate 20 .
It is important to point out that the resistor R 2 shown of FIG. 3 is provided for illustrative purposes only. The thin film coating, on the glass substrate 20 shown in FIG. 3 does not include a resistor R 2 . The circuit 40 only assumes that the thin film coating constitutes a resistor R 2 for modeling purposes. This assumption is valid given that the resistance of the material used for the thin film coating, such as indium tin oxide, is generally found to be a function of the material's temperature.
Based on this assumption, the circuit 40 calculates the temperature T 2 of the thin film coating on the glass substrate 20 using a mathematical modeling technique which involves a two step calculation. This two step calculation is described in detail below with reference to Equations 1 through 4.
First, the circuit 40 calculates the assumed resistance R 2 of the thin film coating. This value is calculated on a realtime basis, usually once every second, by the temperature control circuit 46 .
The temperature control circuit 46 performs this first calculation by using, Equation 1 below.
R 2 =R 1 ( V SUPP /V 1 −1) Equation 1
Referring to Equation 1, R 1 is a known resistance value, V 1 is a known value based on measurements obtained by voltmeter 44 , and V SUPP is a known value. With these known variables, R 2 is calculated by the temperature control circuit 46 .
Once R 2 is computed, the second calculation is performed by the circuit 46 . The second calculation computes the temperature T 2 of the thin film coating on the substrate 20 by using Equations 2 through 4 below.
As indicated above, the resistance R 2 of the thin film coating on glass substrate 20 can be expressed as a function of the coating's temperature. This mathematical temperature is shown as Equation 2 below.
R 2 =R 0 +a ( T 2 −T 0 )+ b ( T 2 −T 0 ) 2 + Equation 2
By truncating Equation 2, the resistance R 2 of the coating can be approximated by Equation 3 below.
R 2 =R 0 +a ( T 2 −T 0 ) Equation 3
Equation 3 can then be solved for T 2 and represented as shown in Equation 4 below.
T 2 =T 0 +( R 2 −R 0 )/ a Equation 4
Referring to Equation 4, T 0 is a reference temperature of the thin film coating contained on glass substrate 20 at which the coating's resistance R 0 is known, R 0 is a resistance of the coating at the temperature T 0 , and the coefficient “a” is a constant that is unique to the particular materials of the coating. With these variables being known and R 2 being known from the first calculation, T 2 is then calculated by the temperature control circuit 46 . This calculation is also performed on a realtime basis which is usually once/second.
By assuming that the thin film coating contained on the glass substrate 20 constitutes a resistor and using the mathematical models described above, the circuit 40 developed in accordance with the present invention calculates the temperature T 2 of the coating on the glass substrate contained within a thin film heater. Moreover, circuit 40 is able to calculate the temperature T 2 in a manner that is minimally impacted by the thermal mass proximate to the thin film heater and does not impact the viewing are of the substrate 20 .
The present invention is not to be considered limited in scope by the preferred embodiments described in the specification. For example, while the invention described herein is used as a device for heating for LCD's, the invention can be used in any type of thin film heating device. Additional advantages and modifications, which will readily occur to those skilled in the art from consideration of the specification and practice of the invention, are intended to be within the scope and spirit of the following claims. | A circuit for controlling the temperature of a thin film conductive heater includes a control circuit for applying a voltage to the heater. The control circuit regulates the temperature of the heater element by using a modeling technique which assumes that the thin film coating functions as a single electrical resistor. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This patent application claims priority of German Patent Application No. 10 2005 047 287.7 filed Oct. 1, 2005, which application is incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a method and a device for operating a drive mechanism, in particular for adjusting an automatic transmission and/or a clutch in a motor vehicle, with the drive mechanism being provided with an engine, which is connected in a driving manner to a mobile element to be positioned.
BACKGROUND OF THE INVENTION
Such a method for operating a drive mechanism provided for shifting an automatic transmission is known from DE 103 16 442 A1. The drive mechanism has a brushless electric motor, which shifts a mobile element of the transmission. In order to position the mobile element, the winding of the electric motor is addressed via a control electronic. The rotation of the mobile element is measured by an incremental rotation measurement signal being determined using reverb sensors. The rotation measurement signal is also used to absolutely determine the position of the mobile element. Using the engine, the mobile element is first brought into a known predetermined position. Subsequently, an absolute position signal is set to a reference value allocated to a reference position. Then the mobile element is displaced out of the reference position in order to select a gear requested by the transmission control. The incremental rotation measurement signal is controlled here, in order to follow the absolute position signal with each change of the incremental position measurement signal. During the positioning process of the mobile element the rotation measurement signal is compared to saved rotation signals. If any deviation is determined, a neutral reference shift is initiated. This largely avoids mistakes even during the shifting of the transmission, which might lead to a critical driving condition, damage to the transmission, and/or a dangerous situation when, due to a malfunction, too many or too few increments were measured in the rotation measurement signal. However, by this reasoning an erroneous positioning of the mobile element cannot be detected or avoided in all cases, in particular, when only few increments were missed or counted in excess and the error remains within the range of the mechanical tolerances and the statistic variations of the measurements.
BRIEF SUMMARY OF THE INVENTION
Therefore, the object is to provide a method of the type mentioned at the outset, which can detect highly accurately any faulty positioning of the mobile element, even when only small errors of the position measurement signal have occurred.
This object is attained in that:
a) the mobile element is brought into a predetermined reference position with the help of the engine and an absolute position signal is set to a reference value allocated to a reference position;
b) the position of the mobile element is changed with the help of the engine and an incremental position measurement signal of the position is created for the mobile element depending on the change of the position;
c) the incremental position measurement signal is controlled and the absolute position signal is followed when a change of the incremental position measurement signal occurs;
d) the mobile element is positioned once more with the help of the engine in the reference position and the position value is determined, which is allocated to the absolute position signal in the reference position;
e) a difference is determined from the position value and the reference value and said value is saved in a data storage;
f) the steps b) through e) are performed at least once more;
g) at least two of the difference values resulting in this manner are added to form a control value; and,
h) and the control value is compared to a predetermined range of target values and that an error condition is recognized when a deviation occurs between the control value and the range of target values.
Thus, in an advantageous manner the generally always present individual deviations in the cycles, determined in two subsequent reference shifts between the position value of the absolute position signal in the reference position and the reference value, are added to a control value over several cycles. Here, errors are largely compensated, which are caused by noise or by individual cycles being once in the positive, once in the negative range. However, errors always pointing in the same direction lead to a nominal increase of the control value. This way, even small mistakes can initiate the detection of an error condition, if it occurs repeatedly. The control value and/or the difference values are preferably saved in a non-volatile data storage so that it remains saved in a motor vehicle even after turning off the ignition.
The above-mentioned object can also be obtained in that:
a) the mobile element is brought into a predetermined reference position with the help of the engine and that an absolute position signal is set to a reference value allocated to said reference position;
b) the position of the mobile element is changed with the help of the engine and an incremental position measurement signal, dependent on the change of position, is created for the mobile element;
c) the incremental position measurement signal is controlled and the absolute position signal is followed when any changes of the incremental position measurement signal occur;
d) the mobile element is repositioned in the reference position with the help of the engine and that the position value of the absolute position signal in the reference position is determined and saved in a data storage;
e) the steps b) through d) are performed at least one more time;
f) the position values determined in this manner are added to a total value and the difference between the total value and the product of the reference value and the number of added positioning values is determined as a control value; and,
g) and the control value is compared to a predetermined range of target values and an error condition is recognized when a deviation of the control value from the range of target values is detected.
In this solution, errors always having the same algebraic sign in the individual cycles cause a nominal increase of the control value as well. Thus, even small mistakes can be detected securely. The total value and the control value are preferably saved in a non-volatile data storage.
In an advantageous embodiment of the invention, the incremental position measurement signal is compared to a saved signal and an error condition is detected when a deviation of the position measurement signal and the saved signal occurs. Here, for example, in an incremental position measurement signal, which performs a predetermined sequence of logical signal levels (e.g., 0 and 1) for an error-free creation of signals, said sequence can be compared to a saved pattern. The positioning of the mobile element is therefore controlled in two different manners, by which errors in positioning can be detected even more securely.
It is advantageous if during and/or after the detection of an error condition the engine becomes blocked. Here, it is assumed that the group of components to be adjusted in the drive mechanism, such as, e.g., an automatic transmission and/or a clutch, is in a secured condition prior to the error being detected and that said condition is to be maintained.
In another beneficial embodiment of the invention, it is assumed that a signal representing a measurement for the reliability of the absolute position signal is provided and that during or after the detection of an error condition said signal is adjusted to a value having a lower reliability allocated. The signal representing a scale for the system confidence can be cyclically controlled and/or at least be called at a predetermined operational condition of the vehicle, in order to initiate a predetermined action, depending on the operational state, such as e.g., a re-initiation of the microcomputer necessary for determining the absolute position signal.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, an exemplary embodiment of the invention is explained in greater detail using the drawing, in which:
FIG. 1 is a schematic representation of a motor vehicle;
FIG. 2 is a graphic representation of a mechanical position (continuous line) of an adjustable element and an absolute position signal (dot-dash line), with the x-coordinate showing the time and the y-coordinate showing the position;
FIG. 3 is a graphic representation of a control value signal deducted from the position signal shown in FIG. 2 ;
FIG. 4 is a representation similar to FIG. 2 , however, with a systematic error being present during the detection of the position signal;
FIG. 5 is a graphic representation of a control value signal deducted from the position signal shown in FIG. 4 ; and,
FIG. 6 is a flow chart explaining the steps performed during the determination of the signal of the control value.
DETAILED DESCRIPTION OF THE INVENTION
A vehicle marked 1 in its entirety in FIG. 1 has a drive train with a drive unit 2 , such as e.g., a motor or an internal combustion engine. Furthermore, clutch 3 and transmission 4 are arranged in the drive train. Clutch 3 is arranged in the power flow between drive unit 2 and transmission 4 , with a drive moment of drive unit 2 being transmitted via clutch 3 to transmission 4 and from transmission 4 on the output side to drive shaft 5 and to subsequent axle 6 as well as to the wheels.
Clutch 3 is provided with driving side 7 and power take-off side 8 , with a torque being transmitted from driving side 7 to take-off side 8 , e.g., by which clutch disc 9 being impinged with force by pressure plate 10 , disc spring 11 , and clutch release bearing 12 , as well as flywheel 13 . For this impingement, clutch release lever 14 is operated via actuator 15 .
Actuator 15 is provided with engine 16 , preferably an electronically commutating electric motor, which is connected via transmission 17 to mobile element 18 , namely a master cylinder of a hydraulic operating device for a clutch. The device is connected to clutch release lever 14 in the drive connection. The control of engine 16 occurs via control device 19 , provided with a control electronic, which is connected via a final stage to a winding of engine 16 .
The motion of mobile element 18 is incrementally detected via clutch-path sensor 20 . For this purpose, several reverb sensors can be arranged, e.g., at the stator of engine 16 , offset in reference to one another in the circumferential direction, which cooperate with permanently magnetic poles provided at the rotor of engine 16 . Each time a magnetic pole is passed, the respective reverb sensor creates an electric impulse.
The force impingement of pressure plate 10 and/or the friction surfaces can be adjusted in a controlled manner according to a provided target value signal via the position of mobile element 18 . Here, pressure plate 10 can be arbitrarily positioned between two end positions and be fixed in the respective location. One of the end positions is equivalent to a fully inserted clutch position and the other end position to a fully extended clutch position.
In order to adjust a torque transmitted by transmission 3 , a position of pressure plate 10 can be controlled, which is located in an intermediate area between the two end positions. For this purpose, mobile element 18 is positioned in an appropriate location with the help of actuator 15 .
In order to allow clutch 3 to be brought into the position required for the torques to be transmitted, an absolute position signal is created indicating the position of the mobile element. For this purpose, in a first step mobile element 18 is brought into a predetermined reference position with the help of engine 16 . This can be achieved, for example, such that mobile element 18 is positioned in a locally fixed position abutting a mechanical stop and that contacting the stop can be detected.
In order to detect the stop, the measurement signal of sensor 20 of the clutch path can be evaluated. If during the control of engine 16 in the direction of the stop the measuring signal remains constant, the stop is detected. Of course, it is also possible to detect the positioning of mobile element 18 abutting the stop independent from the measurement signal of sensor 20 of the clutch path with the help of a separate sensor of the reference position, such as, e.g., an end switch.
As soon as it was detected that the reference position has been reached an absolute positioning signal provided is set to a reference value allocated to the reference position, for example to the value 0.
Now the position of mobile element 18 is changed with the help of an engine, for example, in order to appropriately adjust the position of pressure plate 10 when a change in the target value signal occurs for the impingement of force to pressure plate 10 . The incremental position measurement signal is controlled and, when a change of the incremental position measurement signal occurs, the absolute position signal is appropriately followed.
In FIG. 2 , a potential progression of the measured absolute position signal is shown exemplarily by dot-dash line 21 . Additionally, the actual mechanical position of mobile element 18 is marked by continuous line 22 . It is clearly discernible that line 21 of the position signal only slightly deviates from line 22 for the mechanical position.
The operational condition of motor vehicle 1 is controlled with the help of sensors 23 , 24 , and 25 . In FIG. 1 , in an exemplary manner, two sensors 23 are shown for determining the position of the shift lever and sensor 24 for determining the position of a brake pedal and idling switch 25 .
If the operational state of motor vehicle 1 permits it, mobile element 18 can be repositioned in the reference position with the help of engine 16 . This can be achieved, for example, when no gear is engaged in transmission 4 and thus the transfer of force between drive unit 2 and axle 6 is interrupted.
As soon as the reference position has been detected, first positioning value 26 a is determined for the absolute position signal. As discernible in FIG. 2 , first position value 26 a can deviate from the reference position, for example, due to mechanical tolerances and/or quantization noise.
Now the difference between first position value 26 a and the reference value is determined and saved as a control value in the data storage not shown in greater detail in the drawing ( FIG. 3 ). When the reference value equals zero, the position value 26 a can be saved directly in the data storage. Additionally, the absolute position signal is set to the reference value allocated to the reference position, thus e.g., to the value 0.
Now, the position of mobile element 18 is modified once more with the help of engine 16 , in order to position pressure plate 10 according to the target value signal for the impingement with force.
If permitted by the operational state of motor vehicle 1 , mobile element 18 is positioned once more in the reference position with the help of engine 16 , in order to determine second position value 26 b for the absolute position signal. The difference between second position value 26 b and the reference value is determined and added to the control value saved in the data storage. The result of this addition is saved as the new control value ( FIG. 3 ) in the data storage. The absolute position signal is again set to the reference value allocated to the reference position ( FIG. 2 ).
If necessary, the position of mobile element 18 can be modified again with the help of engine 16 and the mobile element can then be positioned in the reference position in order to determine at least third position value 26 c and to continue the control value in the respective manner. In FIG. 3 , it is discernible that the individual differences between position values 26 a , 26 b , 26 c , on the one hand, and the reference value, on the other hand, show different algebraic signs and therefore the added control value has only small numeric values.
FIGS. 4 and 5 show the mechanical position of mobile element 18 , the absolute positioning signal, and the control value signal for a drive mechanism, in which a systematic error occurs when the absolute position signal is measured, leading to individual differences between positioning values 26 a , 26 b , 26 c , on the one hand, and the reference value, on the other hand, always having the same algebraic sign. It is clearly discernible that the control value increases numerically in each comparison of positions.
In order to detect this error, the control value and/or the control value signal is compared to a predetermined target value range. In FIG. 6 , in processing step 43 , it is discernible that an error condition is detected when a deviation of the control value and/or the control value signal to the target value range occurs, which sets a signal representing a measurement for the reliability of the absolute position signal to a value allocated to a lower reliability. As soon as the operational state of motor vehicle 1 allows, reference shifting is performed, in which the absolute position signal is compared to the reference position and/or an entry is made in the error recording file.
Thus, the invention relates to a method for operating a drive mechanism comprising the following steps:
a) In processing step 31 , a mobile element is brought into a predetermined reference position and an absolute position signal is set to a reference value.
b) In processing step 33 , the position of the mobile element is modified and an incremental position measurement signal is created depending on the change of position.
c) In processing step 35 , the position measurement signal is controlled and the absolute position signal is followed when any change occurs.
d) In processing step 37 , the mobile element is again repositioned in the reference position and the position value is determined that is shown by the absolute positioning signal in the reference position.
e) In processing step 39 , a difference value is determined from the position value and the reference value and saved in the data storage.
f) Steps b) through e) and/or processing steps 33 through 39 are performed at least one more time.
g) In processing step 41 , at least two of the difference values created this way are added to a control value.
h) In processing step 43 , the control value is compared to a predetermined target value range and error state 45 is determined, when a deviation occurs between the control value and the target value range.
Another embodiment is identical to the previous one in processing steps 31 through 37 . In processing step 39 , a difference value is also determined from the position value and the reference value. The loop described in step f) is omitted. In processing step 41 , the actual control value is formed by adding the difference value to the previous control value. In processing step 43 , the control value is compared to the predetermined target value range and an error state is detected when a deviation occurs between the control value and the target value range. It is understood that in this comparison the control value must be weighed by the number of added difference values. Subsequently the method returns to processing step 33 .
LIST OF REFERENCE CHARACTERS
1 Motor vehicle
2 Drive mechanism
3 Clutch
4 Transmission
5 Drive shaft
6 Axle
7 Driving side
8 Take-off side
9 Coupling disc
10 Pressure plate
11 Disc spring
12 Clutch release bearing
13 Fly wheel
14 Clutch release lever
15 Actuator
16 Engine
17 Transmission
18 Mobile element
19 Control unit
20 Clutch path sensor
21 Line
22 Line
23 Sensor for determining the shift position of the lever
24 Sensor for determining the position of the brake pedal
25 Idling switch
26 a First position value
26 b Second positioning value
26 c Third positioning value
31 Processing step
33 Processing step
35 Processing step
37 Processing step
39 Processing step
41 Processing step
43 Processing step
45 Processing step | A method for operating a drive mechanism comprising bringing a mobile element into a predetermined reference position with the help of an engine and setting an absolute position signal to a reference value allocated to a reference position; changing the position of the mobile element with the help of the engine and creating an incremental position measurement signal, depending on the change in position, for the mobile element; controlling the incremental position measurement signal and following the absolute position signal when a change in the incremental position measurement signal occurs; repositioning the mobile element in the reference position with assistance of the engine and determining the position value indicated by the absolute position signal in the reference position; determining a difference value from the position value and the reference value and saving the difference value in a data storage; and, repeating steps b) through e) are performed at least once. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser. No. 11/339,333, filed Jan. 24, 2006; which is a continuation of U.S. application Ser. No. 10/400,045, filed Mar. 25, 2003 (now U.S. Pat. No. 6,988,817); which is a continuation of U.S. application Ser. No. 09/724,588, filed Nov. 28, 2000 (now U.S. Pat. No. 6,536,922); which is a divisional of U.S. application Ser. No. 09/711,355, filed Nov. 9, 2000 (now U.S. Pat. No. 6,601,974); which is a divisional of U.S. application Ser. No. 09/108,263, filed Jul. 1, 1998 (now U.S. Pat. No. 6,220,730).
TECHNICAL FIELD
[0002] The present disclosure describes a special image obscurement device for a light source.
BACKGROUND
[0003] In live dramatic performances controlled lighting is often used to illuminate a performer or other item of interest. The illuminated area for live dramatic performance is conventionally a circular beam of light called a “spot light.” This spot light has been formed from a bulb reflected by a spherical, parabolic, or ellipsoidal reflector. The combination forms a round beam due to the circular nature of reflectors and lenses.
[0004] The beam is often shaped by gobos. FIG. 1 shows a light source 100 with reflector 101 projecting light through a triangular gobo 108 to the target 105 . The metal gobo 108 as shown is a sheet of material with an aperture 110 in the shape of the desired illumination. Here, that aperture 110 is triangular, but more generally it could be any shape. The gobo 108 restricts the amount of light which passes from the light source 100 to the imaging lenses 103 . As a result, the pattern of light 106 imaged on the stage 105 conforms to the shape of the aperture 110 in the gobo 108 .
[0005] Light and Sound Design, the assignee of this application, have pioneered an alternate approach of forming the gobo from multiple selected reflective silicon micromirrors. One such array is called a digital mirror device (“DMD”) where individual mirrors are controlled by digital signals. See U.S. Pat. No. 5,828,485 the disclosure of which are herein incorporated by reference. DMDs have typically been used for projecting images from video sources. Because video images are typically rectangular, the mirrors of DMDs are arranged in a rectangular array of rows and columns.
[0006] The individual mirrors 370 of a DMD are rotatable. Each mirror is mounted on a hinge 372 such that it can rotate in place around the axis formed by the hinge 372 . Using this rotation, individual mirrors 370 can be turned “on” and “off” to restrict the available reflective surface.
[0007] FIG. 2 shows an example of using a DMD 400 to project a triangular illumination by turning “off” some of the mirrors in the DMD 400 . The surface of the DMD 400 exposed to a light source 402 comprises three portions. The individual mirrors which are turned “on” (toward the light source 402 ) make up an active portion 404 . In FIG. 3A , the active portion 404 is triangular. The individual mirrors which are turned “off” (away from the light source 402 ) make up an inactive portion 406 . These pixels are reflected. The third portion is a surrounding edge 408 of the DMD 400 . Each of these portions of the DMD 400 reflects light from the light source 402 to different degrees.
[0008] FIG. 3A shows a resulting illumination pattern 410 with the active area 404 inactive area 406 and cage 408 .
SUMMARY
[0009] The inventors recognize that light reflected from the inactive portion 406 of the DMD 400 generates a dim rectangular penumbra 418 area surrounding the bright desired area 404 . Light reflected from the edge 408 of the DMD 400 generates a dim frame area. The inventors recognized that this rectangular penumbra 418 is not desirable.
[0010] The inventors also recognized that a circular penumbra is much less noticeable in the context of illumination used in dramatic lighting.
[0011] Accordingly the inventors have determined that it would be desirable to have a device which would provide a circular illumination without a rectangular penumbra while using a rectangular arrayed device as an imaging surface. The present disclosure provides such capabilities.
[0012] This disclosure describes controlling illumination from a light source. The disclosed system is optimized for use with a rectangular, arrayed, selective imaging device.
[0013] In a preferred embodiment, a rotatable shutter with three positions is placed between a DMD and the imaging optical system. The first position of the shutter is a mask, preferably a circle, placed at a point in the optical system to be slightly out of focus. This circle creates a circular mask and changes any unwanted dim reflection to a circular shape. The second position of the shutter is completely open, allowing substantially all the light to pass. The third position of the shutter is completely closed, blocking substantially all the light from passing.
[0014] An alternate embodiment for blocking the rectangular penumbra by changing any penumbra to round uses an iris shutter placed between a DMD and increases optics. The iris shutter creates a variable aperture which ranges from completely closed to completely open. Intermediate settings include circles of varying diameter, resulting in similar projections as with the first position of the shutter embodiment.
[0015] Another alternate embodiment for blocking the rectangular penumbra by changing any penumbra to round uses two reflective surfaces. The first reflective surface is a DMD. The second reflective surface is preferably a light-sensitive reflective surface such as a polymer. If the light striking a portion of the reflective surface is not sufficiently bright, that portion will not reflect the full amount of that light.
[0016] By controlling the penumbra illumination surrounding the desired illumination, DMDs and other pixel-based rectangular elements can be used in illumination devices without creating undesirable rectangular penumbras.
DESCRIPTION OF DRAWINGS
[0017] FIG. 1 shows a conventional illumination device including a gobo.
[0018] FIG. 2 shows an illumination device including a DMD.
[0019] FIGS. 3A-3G shows a illumination patterns.
[0020] FIG. 4 show the optical train.
[0021] FIG. 5 shows a three position shutter according to a preferred embodiment of the present invention.
[0022] FIG. 6A shows an illumination device including a three position shutter according to a preferred embodiment of the present invention which is set to a mask position.
[0023] FIG. 6B shows an illumination pattern resulting from the device shown in FIG. 6A .
[0024] FIG. 7 shows an iris-type shutter.
[0025] FIGS. 8A and 8B show use of the adjustable iris in a DMD system.
[0026] FIG. 9 shows a three-position shutter with an iris system.
[0027] FIG. 10 shows an embodiment with a light.
DETAILED DESCRIPTION
[0028] The structure and operational parameters of preferred embodiments will be explained below making reference to the drawings.
[0029] The present system uses two different operations to minimize the viewable effect of the unintentional illumination, or penumbra, discussed previously. A first operation forms the optics of the system in a way which prevents certain light from being focused on the DMD and hence prevents that light from being reflected. By appropriately masking the incoming light to the DMD, certain edge portions of the penumbra can be masked. A second part of the system uses a special illumination shutter to provide different shaped penumbras when desired.
[0030] The overall optical system is shown in FIG. 4 . The bulb assembly 200 includes a high wattage bulb, here an MSR 1200 SA Xenon bulb 202 and retroreflectors 204 which capture some of the output from that bulb. The output of the bulb is coupled to a dichroic or “cold” mirror 206 which reflects the visible light while passing certain portions of the infrared. The first focus of the reflector is at Point 208 . A DMD mask is located at that point. The DMD mask is preferably rectangular, and substantially precisely the shape of the inner area 418 of the DMD. The image of the mask is also focused onto the DMD: such that if one were looking at the mask from the position of the DMD, one would see the mask clearly and in focus.
[0031] A first color system includes an RGB system 210 and a parameter color system 212 . The light passes through all of these elements and is then further processed by an illumination relay lens 214 and then by an imaging relay lens 216 . The image relay lens 216 has an aperture of 35 millimeters by 48 millimeters. The output is focused through a field lens 218 to the DMD 400 . The off pixels are coupled to heat sink 220 , and the on pixels are coupled via path 222 back through the imaging relay 216 folded in the further optics 224 and finally coupled to zoom elements 230 . The zoom elements control the amount of zoom of the light beam. The light is colored by a designer color wheel 232 and finally focused by a final focus element 235 controlled by motor assembly 236 .
[0032] The way in which the outer penumbra is removed will be explained with reference to FIGS. 3A and 8B .
[0033] FIG. 3B shows the front surface of the DMD. This includes a relatively small inner active portion 350 which includes the movable mirrors. Active portion 350 is surrounded by a white inactive portion 352 which is surrounded by packaging portion 354 , a gold package 356 , and a ceramic package 358 . Light is input at a 20° angle from the perpendicular. The reason why becomes apparent when one considers FIG. 3C . The mirrors in the DMD tip by 10°.
[0034] FIG. 3C shows two exemplary mirrors, one mirror 360 being on, and the other mirror 361 being off. Input light 362 is input at a 20° angle. Hence, light from the on mirror emerges from the DMD perpendicular to its front surface shown as 364 . However, the same light 362 impinging on an off mirror emerges at a different angle shown as 366 . The difference between those two angles forms the difference 367 between undesired light and desired light. However, note in FIG. 3C what happens when the incoming light 362 hits a flat surface. Note the outgoing beam 368 is at a different angle than either the off position or the on position. The hypothetical beam 366 from an off mirror is also shown.
[0035] The inventors recognize, therefore, that a lot of this information falls within an undesired cone of light. All light which is input (e.g. 362 rays) can be filtered by removing the undesired cone. This is done according to the present disclosure by stopping down the cone of light to about 18° on each side. The final result is shown in FIG. 3D . The incoming light is stopped down to a cone of 18° by an F/3.2 lens. The incoming light is coupled to the surface of the DMD 400 , and the outgoing light is also stopped to a cone of 18°. These cones in the optical systems are identified such that the exit cone does not overlap with the undesired cone 367 shown in FIG. 3C .
[0036] This operation is made possibly by appropriate two-dimensional selection of the incoming light to the digital mirror. FIG. 3E shows the active portion 350 of the digital mirror. Each pixel is a rectangular mirror 370 , hinged on axis 372 . In order to allow use of this mirror and its hinge, the light needs to be input at a 45° angle to the mirror, shown as incident light ray 374 . The inventors recognized, however, that light can be anywhere on the plane defined by the line 374 and perpendicular to the plane of the paper in FIG. 3E . Hence, the light of this embodiment is input at the FIG. 3F which represents a cross section along the line 3 E- 3 F. This complex angle enables using a plane of light which has no interference from the undesired portions of the light. Hence, by using the specific desired lenses, reflections of random scattered illumination is bouncing off the other parts is removed. This masking carried out by at least one of the DMD mask 208 and the DMD lens 218 . By appropriate selection of the input light, the output light has a profile as shown in FIG. 3G . 350 represents the DMD active area, 356 represents the package edge, and 358 represents the mount. The light output is only from the DMD active area and is stopped and focused by appropriate lenses as shown in FIG. 3G .
[0037] FIG. 5 shows a planar view of a shutter 500 according to a preferred embodiment of the invention. The preferred configuration of the shutter 500 is a disk divided into three sections. Each section represents one position to which the shutter 500 may be set. The shutter 500 is preferably rotated about the center point 502 of the shutter. The gate of the light is off center, to allow it to interact with one of the three sections. Rotation is preferred because rotation allows efficient transition between positions. Alternately, the shutter 500 may slide vertically or horizontally to change from one position to another. A round shape is preferred because of efficiency in material and space use. Alternately, the shutter 500 may be rectangular or some other polygonal shape.
[0038] Three positions are preferred because each position is rotatably equidistant from the other positions. However, a shutter 500 with three positions provides more positions than a shutter 500 with only two positions.
[0039] In a preferred embodiment, a first position is a mask position 504 . The mask position 504 includes an open or transparent aperture 506 and an opaque mask portion 508 which is not permeable to light. Preferably, material is removed from the shutter 500 leaving a shaped aperture 506 and a mask portion 508 .
[0040] The second position is an open position 510 . The open position 510 includes an opening 512 . Preferably the opening 512 is formed by removing substantially all material from the shutter 500 in the section of the open position 510 .
[0041] The third position is a closed position 514 . The closed position 514 includes a opaque barrier portion 516 . Preferably, the barrier portion 516 is just a solid block of material.
[0042] FIG. 6A shows a preferred embodiment of an illumination system. A shutter 500 of the type shown in FIG. 5 is rotatably mounted between a light source 602 /DMD 604 such that substantially all the light from the light source 602 strikes only one section of the shutter 500 at a time. The shutter 500 is rotatably positioned to the mask position 504 . Thus, when the light source 602 is activated, light from the light source 602 reflected by DMD 604 strikes only the mask position 504 of the shutter 500 .
[0043] Using digital control signals, the DMD 604 is set so that an active portion 404 of the individual mirrors are turned “on” and an inactive portion 406 of the individual mirrors are turned “off” (see FIG. 3A ). The shape of the active portion 404 is set to conform to the desired shape of the bright portion of the illumination reflected by the DMD 604 shown in FIG. 6B , described below.
[0044] FIG. 6B shows an illumination pattern generated by the illumination device 600 configured as shown in FIG. 6A .
[0045] Returning to FIGS. 3A and 3B , when the shutter 500 is not interposed between the DMD 400 and the stage. All portions of the DMD 400 reflect the light and create the undesirable illumination pattern shown in FIG. 3A . In particular, the bright triangular area 404 is surrounded by an undesirable dim rectangular penumbra 418 and slightly brighter frame 422 .
[0046] As described above, the illumination pattern shown in FIG. 6B does not include a dim rectangular penumbra 418 and a slightly brighter frame 422 . These undesirable projections are substantially eliminated by using the shutter 500 and the aperture 506 . A dim penumbra illumination is generated by light reflecting from the inactive portion of the DMD 604 . This dim circular penumbra illumination is more desirable than the dim rectangular penumbra and slightly brighter frame 422 of FIG. 3A because the shape of the dim penumbra illumination is controlled by the shape of the aperture 506 . Accordingly, the dim penumbra illumination can be conformed to a desirable shape.
[0047] FIG. 7 shows an alternate embodiment for an iris shutter 900 . Preferably, a series of opaque plates 902 are arranged inside a ring 904 to form an iris diaphragm. By turning the ring 904 the plates 902 move so that an iris aperture 906 in the center of the iris shutter 900 varies in diameter. The iris aperture 906 preferably varies from closed to a desired maximum open diameter. Preferably the iris shutter 900 can transition from closed to a maximum diameter (or the reverse) in 0.1 seconds or less.
[0048] FIG. 8A shows an illumination device 1000 including an iris shutter 900 as shown in FIG. 7 . The iris shutter 900 is positioned between a DMD 1004 and a stage 1002 . In FIG. 8A , the iris shutter 900 is partially open such that the iris aperture 906 allows part of the light 1006 , 1008 from the light source 1002 to pass through, similar to the mask position 504 of the three position shutter 500 shown in FIG. 5 . One difference between the mask position 504 and the iris shutter 900 is that the iris aperture 906 is variable in diameter while the aperture 506 of the mask position 504 is fixed. The remainder of the light 1010 from the light source 1002 is blocked by the plates 902 of the iris shutter 900 . The light 1006 , 1008 which passes through the iris aperture 906 strikes the DMD 1004 in a pattern 1012 which is the same shape as the shape of the iris aperture 906 . Through digital control signals, some of the individual mirrors of the DMD 1004 are turned “on” to form an active portion 1014 , and some of the individual mirrors are turned “off” to form an inactive region 1016 . Preferably, the pattern 1012 is at least as large as the active portion 1014 of the DMD.
[0049] FIG. 8B shows an illumination pattern 1018 generated by the illumination device 1000 shown in FIG. 8A . Similar to FIGS. 6A and 6B , a bright illumination 1020 is generated by light 1022 , 1020 reflected from the active portion 1014 of the DMD 1004 . A dim penumbra illumination 1024 is generated by light 1026 reflected from the inactive portion 1016 of the DMD 1004 . By varying the diameter of the iris aperture 906 , the size of the pattern 1012 on the DMD 1004 changes. As the pattern 1012 changes the amount of the inactive portion 1016 of the DMD 1004 which is struck by light 1008 from the light source 1002 changes and so the dim penumbra 1024 changes as well.
[0050] FIG. 9 shows an alternate embodiment of a shutter 1100 which combines features of a three position shutter 500 with an iris shutter 900 . The overall configuration of this shutter 1100 is that of the three position shutter 500 . However, instead of the mask portion 504 as shown in FIG. 5 and FIG. 6A , one of the positions is an iris portion 1102 . The iris portion 1102 has an iris diaphragm 1104 inserted into the material of the shutter 1100 . Similar to the iris shutter 900 of FIG. 7 , the iris diaphragm 1104 is made from a series of opaque plates 1106 arranged inside a ring 1108 . By turning the ring 1108 the plates 1106 move so that an iris aperture 1110 in the center of the iris diaphragm 1104 varies in diameter. This configuration operates in most respects similarly to the three position shutter 500 as shown in FIG. 5 and FIG. 6A . Because of the iris diaphragm 1104 , the amount of light blocked by the iris portion 1102 is variable.
[0051] FIG. 10 shows an alternate embodiment of an illumination device 1200 which includes a second reflective surface 1220 . A light source 1204 projects light onto a DMD 1206 which has an active portion 1208 and an inactive portion 1210 . Light reflects off the DMD 1206 and strikes the second reflective surface 1220 . The second reflective surface 1220 acts to reduce the dim penumbra and frame created by the inactive 1210 and edge 1212 of the DMD 1206 (recall FIGS. 3A and 3B ), leaving the active portion 1222 , to project image 1246 .
[0052] In the embodiment shown in FIG. 10 , the second reflective surface 1220 is a light sensitive surface such as an array of light trigger cells. Only light of a certain brightness is reflected. If the light striking a cell is insufficiently bright, substantially no light is reflected by that cell. Alternately, the second reflective surface 1220 may be made of a polymer material that only reflects or passes light of sufficient brightness. Light 1224 reflected from the active portion 1208 of the DMD 1206 is preferably bright enough to be reflected from the second reflective surface 1220 . Light 1230 reflected from the inactive portion 1210 and the edge 1212 of the DMD 1206 is preferably not bright enough to be reflected from the second reflective surface 1220 . Thus, only light 1224 from the active portion 1208 of the DMD 1206 will be reflected from the second reflective surface 1220 . As described above, the undesirable dim rectangular penumbra 418 and slightly brighter frame 422 (recall FIG. 3A ) would be created by light 1230 reflected from the inactive portion 1210 and edge 1212 of the DMD 1206 . The second reflective surface 1220 does not reflect this dim light 1230 and so wholly eliminates the dim penumbra and frame from the resulting illumination.
[0053] A number of embodiments of the present invention have been described which provide controlled obscurement of illumination. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, filters or lenses might be introduced to the illumination device 600 shown in FIG. 6A between the shutter 500 and the DMD 604 . Alternately, the light source might be a video projection device or a laser.
[0054] While this disclosure describes blocking the light before impinging on the DMD, it should be understood that this same device could be used anywhere in the optical train, including downstream of the DMD. Preferably the blocking is at an out of focus location to soften the edge of the penumbra, but could be in-focus.
[0055] The light reflecting device could be any such device, including a DMD, a grating light valve (“GLV”), or any other arrayed reflecting device which has a non-circular shape.
[0056] All such modifications are intended to be encompassed in the following claims. | An illumination obscurement device for controlling the obscurement of illumination from a light source which is optimized for use with a rectangular, arrayed, selective reflection device. In a preferred embodiment, a rotatable shutter with three positions is placed between a light source and a DMD. The first position of the shutter is a mask, preferably an out of focus circle. This out of focus circle creates a circular mask and changes any unwanted dim reflection to a circular shape. The second position of the shutter is completely open, allowing substantially all the light to pass. The third position of the shutter is completely closed, blocking substantially all the light from passing. By controlling the penumbra illumination surrounding the desired illumination, DMDs can be used in illumination devices without creating undesirable rectangular penumbras. | 8 |
REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 13/022,241, filed Feb. 7, 2011, now U.S. Pat. No. 8,064,669, which is a continuation of U.S. patent application Ser. No. 11/437,230, filed May 19, 2006, now U.S. Pat. No. 7,889,905, which claims priority to U.S. Provisional Patent Application Ser. No. 60/683,588, filed May 23, 2005. The entire content of each application is incorporated herein by reference.
STATEMENT OF GOVERNMENT SPONSORSHIP
This invention was made with government support under Grant No. CA074325, awarded by the National Institutes of Health. The Government has certain rights in the invention.
FIELD OF THE INVENTION
This invention relates generally to image correlation and, in particular, to a fast image registration method applicable to guided endoscopy and other fields.
BACKGROUND OF THE INVENTION
Registration and alignment of images taken by cameras at different spatial locations and orientations within the same environment is a task which is vital to many applications in computer vision and medical imaging. For example, registration between images taken by a mobile camera and those from a fixed surveillance camera can assist in robot navigation. Other applications include the ability to construct image mosaics and panoramas, high dynamic range images, or super-resolution images, or the fusion of information between the two sources.
However, because the structure of a scene is inherently lost by the 2D imaging of a 3D scene, only partial registration information can typically be recovered. In many applications, depth maps can be generated or estimated to accompany the images in order to reintroduce the structure to the registration problem.
Most currently available 2D alignment algorithms use a gradient descent approach which relies on three things: a parameterization of the spatial relationship between two images (e.g., the 2D rotation and translation between two 2D images), the ability to visualize these images under any value of the parameters (e.g., viewing a 2D reference image rotated by 30 degrees), and a cost function with associated image gradient information which allows an estimate of the parameter updates to be calculated. Among the most straightforward and earliest of these algorithms is the Lucas-Kanade algorithm, which casts image alignment as a Gauss-Newton minimization problem [5]. A subsequent refinement to this algorithm includes the inverse compositional alignment algorithm which greatly speeds the computation of the parameter update by recasting the problem, allowing all gradient and Hessian information to be calculated one time instead of every iteration [6]. Several other improvements have centered around the choice of parameters and the corresponding image warps these parameterizations induce. For example, images obtained from two identical cameras observing the same scene from a different location can be approximately related by an affine transformation or an 8-parameter homography [7].
The main problem with these types of parameterizations is that they do not truly capture the physically relevant parameters of the system, and, in the case of the homography, can lead to overfitting of the image. A more recent choice of parameters attempts to match two images obtained from a camera that can have arbitrary 3D rotations around its focal point [8]. This algorithm succeeds in extracting the physically relevant parameters (rotation angles about the focal point). However, while it is able to handle small translations, it cannot handle general translation and treats it as a source of error.
Little has been done to tackle the problem of registration of two images generated by cameras related by a general rigid transformation (i.e., 3D rotation and translation). The main reason for this is that the accurate visualization of a reference image as seen from a different camera location ideally requires that the depth map associated with that image be known—something which is not generally true. In certain situations, such as a robot operating in a known man-made environment, or during bronchoscopy where 3D scans are typically performed before the procedure, this information is known. Indeed, even in situations where the depth map is unknown, it can often be estimated from the images themselves.
An example of this is the aforementioned shape-from-shading problem in bronchoscopy guidance [9]. Current practice requires a physician to guide a bronchoscope from the trachea to some predetermined location in the airway tree with little more than a 3D mental image of the airway structure, which must be constructed based on the physician's interpretation of a set of computed tomography (CT) films. This complex task can often result in the physician getting lost within the airway during navigation [1]. Such navigation errors result in missed diagnoses, or cause undue stress to the patient as the physician may take multiple biopsies at incorrect locations, or the physician may need to spend extra time returning to known locations in order to reorient themselves.
In order to alleviate this problem and increase the success rate of bronchoscopic biopsy, thereby improving patient care, some method of locating the camera within the airway tree must be employed. Fluoroscopy can provide intraoperative views which can help determine the location of the endoscope. However, as the images created are 2D projections of the 3D airways, they can only give limited information of the endoscope position. Additionally, fluoroscopy is not always available and comes with the added cost of an increased radiation dose to the patient.
A few techniques also exist that determine the bronchoscope's location by attempting to match the bronchoscope's video to the preoperative CT data. One method uses shape-from-shading, as in [2], to estimate 3D surfaces from the bronchoscope images in order to do 3D-to-3D alignment of the CT airway surface. This method requires many assumptions to be made regarding the lighting model and the airway surface properties and results in large surface errors when these assumptions are violated. A second method of doing this is by iteratively rendering virtual images from the CT data and attempting to match these to the real bronchoscopic video using mutual information [3] or image difference [4].
While these methods can register the video to the CT with varying degrees of success, all operate very slowly and only involve single-frame registration—none of them are fast enough to provide continuous registration between the real video and the CT volume. They rely on optimization methods which make no use of either the gradient information nor the known depth of the CT-derived images, and thus require very computationally intensive searches of a parameter space.
SUMMARY OF THE INVENTION
This invention resides in a novel framework for fast and continuous registration between two imaging modalities. A method of registering an image according to the invention comprises the steps of providing a set of one or more reference images with depth maps, and registering the image to at least one of the reference images of the set using the depth map for that reference image. The image and the reference set may both be real, virtual, or one real with the other virtual. The set of reference images may endoscopic, derived from a bronchoscope, colonoscope, laparoscope or other instrument. The registration preferably occurs in real-time or near real-time, and one or more of the images in the set of reference images can be updated before, during, or after registration.
According to a robust implementation, the set of reference images represents viewpoints with depth maps and image gradients, and the image to be registered is derived from a video feed having a plurality of consecutive frames. The method includes the steps of:
a) warping a frame of the video to the nearest viewpoint of the reference source;
b) computing an image difference between the warped video frame and the reference image;
c) updating the viewpoint using a Gauss-Newton parameter update; and
d) repeating steps a) through c) for each frame until the viewpoint converges or the next video frame becomes available.
The invention makes it possible to completely determine the rigid transformation between multiple sources at real-time or near real-time frame-rates in order to register the two sources. A disclosed embodiment involving guided bronchoscopy includes the following steps:
1. In the off-line phase, a set of reference images is computed or captured within a known environment, complete with corresponding depth maps and image gradients. The collection of these images and depth maps constitutes the reference source.
2. The second source is a real-time source from a live video feed. Given one frame from this video feed, and starting from an initial guess of viewpoint, the real-time video frame is warped to the nearest viewing site of the reference source.
3. An image difference is computed between the warped video frame and the reference image.
4. The viewpoint is updated via a Gauss-Newton parameter update.
5. Steps 2-4 are repeated for each frame until the viewpoint converges or the next video frame becomes available. The final viewpoint gives an estimate of the relative rotation and translation between the camera at that particular video frame and the reference source.
The invention has far-reaching applications, particularly in the field of assisted endoscopy, including bronchoscopy and colonoscopy. Other applications include aerial and ground-based navigation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a block diagram of registration algorithm for guided bronchoscopy;
FIGS. 2A-2F show source images and results for virtual-to-real registration; specifically, FIG. 2A shows a real video frame, FIG. 2B shows a warped real image at initial viewpoint, FIG. 2C shows edges from final reference image overlaid, FIG. 2D shows a reference virtual image corresponding to final registration, FIG. 2E shows a warped real image at final viewpoint, and FIG. 2F shows edges of corresponding virtual image overlaid; and
FIGS. 3A-3C show source images and sample results for virtual-to-virtual registration; specifically, FIG. 3A shows a real image, FIG. 3B shows a reference image, and FIG. 3C shows a warped real image.
DETAILED DESCRIPTION OF THE INVENTION
Broadly, this invention is a 2D image alignment algorithm which is augmented to three dimensions by introducing the depth maps of the images. The method provides an ideal way to extend the existing matching framework to handle general 3D camera motion, allowing one to directly solve for the extrinsic parameters of the camera and localize it within its environment.
For the purpose of explaining the method in a very concrete fashion, discussion shall focus on a situation similar to that used in guided bronchoscopy. In a typical bronchoscopic procedure, a CT scan is initially performed and can subsequently be processed to extract the airway tree surfaces. The interior of the hollow airway tree constitutes the known environment. During bronchoscopy, the bronchoscope is inserted into the airways and a camera mounted on the tip transmits in real-time a sequence of real bronchoscopic (RB) video images. Assuming that the calibration parameters of the endoscope are known, virtual bronchoscopic (VB) images (endoluminal renderings) can be rendered at arbitrary viewpoints within the airway tree. It is also clear that the depths corresponding to each pixel of the VB image can be immediately calculated and form a virtual depth map (VDM).
The problem is that we have a fixed real-time RB image from an unknown location within the interior of an airway, but we also have a known VB source with known location and 3D information that enables us to create manifestations of the same hollow airway structure from arbitrary viewpoint. Given the above setup, the goal is to locate the source of the RB image by attempting to find the best match between that fixed RB image and any possible VB endoluminal rendering. A fairly straightforward approach to accomplish this is by employing a Gauss-Newton gradient descent algorithm that attempts to minimize a difference measure between the RB image and the VB image with respect to the viewing parameters (i.e., viewpoint) of the virtual image. The method for doing this is similar to the Lucas-Kanade image alignment algorithm [5].
The objective function used in [5, 6] is the sum squared difference (SSD) between the pixel intensities of the two images, although weighted SSD is equally viable, and weighted or unweighted normalized cross-correlation (CC) can be used if some additional weak assumptions are made. Using the SSD, the objective function can thus be written as
E = ∑ u , v [ I v ( u , v ; p + Δ p ) - I r ( u , v ) ] 2 ( 1 )
where p is the vector of viewing parameters, I v (u, v; p+Δp) is the virtual VB image rendered from the viewpoint p+Δp, u and v are the row and column indices, and I r is the real RB image. Following the procedure of [5], it is shown that that the Gauss-Newton parameter update Δp can be found as
Δ p = H - 1 ∑ u , v [ ∂ I ∂ p ] [ I v ( u , v ; p ) - I r ( u , v ) ] ( 2 )
where the Hessian H is approximated per Gauss-Newton as
H = ∑ u , v [ ∂ I v ∂ p ] u , v ; p T [ ∂ I v ∂ p ] u , v ; p ( 3 )
Where
[ ∂ I v ∂ p ] u , v ; p
is a vector that gives the change in the intensity of a pixel (u, v) in a VB image I v rendered at viewpoint p with respect to each of the components of the parameter vector Δp.
[ ∂ I v ∂ p ] p
can also be interpreted as a vector of steepest descent images, where each component of the vector is actually an image that describes the variation of the image intensities with respect a component of the parameter vector. Because the steepest descent images
[ ∂ I v ∂ p ] p
change at every viewpoint p, they, and the Hessian must be recomputed every iteration, leading to a very computationally costly algorithm.
To speed up the iteration, the inverse compositional algorithm was proposed [6]. Under this strategy, instead of moving the virtual viewpoint towards the real viewpoint using the parameter update, we instead move the real viewpoint toward the virtual viewpoint using the inverse of the parameter update. Since the computer obviously has no control over the location of the bronchoscope tip, this may seem to be an unfeasible strategy. However, using a depth-based warping, the RB image can be warped to simulate its appearance from other viewpoints. This strategy results in comparing a warped version of the real image to a stationary virtual image. Under this formulation, the objective function we seek to minimize is:
E
=
∑
u
,
v
[
I
v
(
u
,
v
;
Δ
p
)
-
I
r
(
W
(
u
,
v
,
Z
r
;
p
)
)
]
2
(
4
)
The warping function W(•) warps the image coordinates of the RB image I r and hence warps the image itself. It is important also to note that the warp in this case is dependent on the depth map of the real image Z r . Solving for the Gauss-Newton parameter update associated with 4 yields
Δ
p
=
H
-
1
|
p
=
0
→
∑
u
,
v
[
∂
I
∂
p
]
u
,
v
;
0
→
[
I
r
(
W
(
u
,
v
,
Z
r
;
p
)
)
-
I
v
(
u
,
v
)
]
(
5
)
While this may seem to add unnecessary complexity and error to the problem, it actually serves to greatly speed the iteration and has the additional side benefit of eliminating the need to render arbitrary viewpoints on the fly if you instead have a collection of pre-rendered (or pre-captured) images and corresponding depth maps. The reason for this significant increase in speed is that the VB image and VB image gradients are always evaluated at p=0, the reference viewing site, and as such allows all of the following operations to be pre-computed before iteration begins:
1. The known environment is sampled as a set of viewing sites.
2. Virtual images I v are pre-rendered at each viewing site.
3. Virtual depth maps Z v are computed at each site.
4. Steepest descent images
[ ∂ I v ∂ p ]
are computed with respect to each of the viewing parameters in vector p.
5. The inverse Hessian H −1 is Gauss-Newton estimated from the steepest descent images
[ ∂ I v ∂ p ]
via equation (14).
The iterative portion of the algorithm may then be carried out in the following steps:
1. Warp the real image from pose p to the nearest reference site.
2. Compute the error image [I r (W(u,v,Z r ;p))−I v (u,v;{right arrow over (0)}).
3. Compute the parameter update Δp via equation (5).
4. Find the new values of p by incrementing the old parameters by the inverse of the update (Δp) −1 .
These steps are illustrated in FIG. 1 . Ignoring the warp function, all the equations presented thus far are general and can apply equally well to 2D transformations, such as affine or homography, or 3D rotations. The focus is now narrowed, however, to the full 3D motion case with our choice of coordinate system and parameters. One may realize from inspection of the warps in (4) that the problem is defined in terms of several local coordinate systems as each reference view is defined to be at p={right arrow over (0)}, yielding a different coordinate system for each viewing site used. It is, however, a trivial matter to relate each of these coordinate systems to a global coordinate frame in order to perform parameter conversions between frames. Therefore, given a camera pose with respect to the global camera frame, we can define our parameter vector as
p=[θ r θ p θ y t x t y t z ] T (6)
with three Euler rotation angles and three translations with respect to the nearest reference view.
With this parameterization, the warping W(u,v,Z;p) is governed by the matrix equation
[ u ′ z ′ f v ′ z ′ f Z ′ ] = R [ u Z f v Z f Z ] + [ t x t y t z ] ( 7 )
where R is the rotation matrix defined by the Euler angles (θ r , θ p , θ y ), u and v are the columns and rows of the image, f is the focal length, and Z is the entry on the depth map Z corresponding to the point (u,v). Here (u′,v′) gives the warped image coordinate of interest, and Z′ gives the warped depth corresponding to that point. Note that in the problem statement, we assume only that the virtual depth map Z v is known. However, when using the inverse compositional algorithm, the warp is applied to the real image I r and the real depth map Z r must first be calculated by warping the virtual depth map Z v to the current estimated pose of the real camera via p. This can also be performed using (7) and then interpolating the resulting warped depth map onto the coordinate system of the real image. In doing so, we are implicitly assuming that our estimate of p is relatively close to its actual value. If this is not the case, the parameter error can lead to large errors in the real depth map Z r , and therefore large errors in the image warping. Under such circumstances, the forward gradient descent method governed by (1-2) may be better suited to the problem.
In order to apply the warping function, at each pixel coordinate (u,v), with intensity I(u,v) and depth Z(u,v), a new coordinate (u′,v′) and depth Z′(u′,v′) are found via (7). The original intensities and depths may then be mapped onto the new image array I(u′,v′). Some special care must be taken when performing the warping. Firstly, the image difference in (4) requires that the coordinate locations be the same for both images. The resultant array must therefore be interpolated onto the same coordinate grid as the original arrays. Because of this interpolation, and because the depth-based warping may result in occlusion, it can be difficult to choose the proper intensity corresponding to an output pixel. This can be mitigated somewhat if the intensities corresponding to larger depths are discarded when they overlap with those of smaller depths.
Finally, we turn to the calculation of the steepest-descent images
[ ∂ I ∂ p ] .
There are several ways to generate the steepest descent images. They may be generated numerically by taking the difference of the reference images warped to small positive and negative values of each parameter. They may also be generated analytically by expanding the derivative via the chain rule:
∂ I ∂ p = [ ∇ u I ∇ v I ] J p ( 8 )
where ∇ u I and ∇ v I are the image gradients with respect to the rows and columns of the image, and J p is the Jacobian of the warped coordinates with respect to p and thus can be found by differentiating u′ and v′ from (7) with respect to each of the warp parameters and evaluating it at a particular current value of p. In the case of the inverse compositional algorithm, the image derivatives are always evaluated at p={right arrow over (0)} and thus the Jacobian is constant for each reference viewing site:
J
p
=
[
-
v
-
u
v
f
-
f
-
u
2
f
f
z
0
-
u
z
-
u
-
f
-
v
2
f
-
v
u
f
0
f
z
-
v
z
]
(
9
)
We now have all the necessary information to calculate the iterated parameter update Δp. The final step is to invert this update, and compose it with the current estimate of p. The Euler angles can be found from the rotation matrix resulting from
R′=RR d T (10)
where R d is the incremental rotation matrix associated with the rotation angles in Δp. The updated translations can be found from
( t z ′ t y ′ t z ′ ) = ( t z t y t z ) - RR d T ( Δ t x Δ t y Δ t z ) ( 11 )
where Δt i are the translation elements of the parameter update Δp.
In order to improve the performance when applying the above approach, several optimizing techniques are used. Operations performed on full-resolution images can be very computationally intensive. Therefore, a resolution pyramid is used wherein all images, depth maps, and gradients are down-sampled, preferably by a factor of 4, at each level. As we are not particularly concerned with computation time regarding the precomputed virtual views and gradients, and most video capture hardware provides real-time hardware subsampling for the real image, the computational cost of this subsampling is inconsequential and provides much quicker iteration times.
When implementing the above registration algorithm using pyramid decomposition, the algorithm is begun at the lowest resolution level of the pyramid (experimental results in this paper were performed starting at level 3; i.e., a factor of 64 reduction in resolution) and run until a reasonable stopping criteria was met before proceeding to a higher resolution level. This pyramidal approach not only speeds computation, it also serves to prevent convergence to local optima, because only the largest features are present in the highly subsampled images, while sharper features are introduced in higher resolution levels to aid in fine adjustment.
A second optimization that is used in practice is the use of the weighted normalized cross-correlation objective function
E = - ∑ u , v w u , v [ I v ( W ( u , v , Z ; Δ p ) ) - μ v σ v ] [ I r ( W ( u , v , Z ; p ) ) - μ r σ r ] ( 12 )
that allows images of different mean intensities and intensity ranges to be compared and also allows weighting of individual pixel values. It should be noted that in order to use this objective function under the inverse compositional algorithm, the weights must be constant and they must be chosen prior to the computation of the steepest descent images (i.e. they must be based off features of the virtual images). Taking advantage of the equivalence of normalized SSD and normalized cross-correlation, the update can be found as:
Δ p = H - 1 | p = 0 ∑ u , v w u , v [ ∂ I ∂ p ] _ p = 0 T [ I _ r ( W ( u , v , Z ; p ) ) - I _ v ( u , v ) ] ( 13 )
where the Hessian in this case is
H
=
∑
u
,
v
w
u
,
v
[
∂
I
∂
p
]
_
T
[
∂
I
∂
p
]
_
(
14
)
[ ∂ I ∂ p ] _
is the set of mean-subtracted steepest descent images divided by the variance of the virtual image I v , and I i i are the normalized images.
EXAMPLES
To validate the algorithm, sample results for the virtual-to-real and virtual-to-virtual registration cases are given. In both of the cases outlined below, the virtual environment is a CT chest scan of a human patient designated h005. The airway surfaces were automatically generated using the methods of Kiraly et al. [10]. Airway centerlines were extracted using the methods of Swift et al. and the virtual viewing sites were chosen along these airway centerlines at intervals varying between 0.3 mm and 1 mm, with the viewing direction chosen parallel to the airway centerline [11]. Virtual images and depth maps were generated by an OpenGL renderer assuming a spot light source at the camera focal point, a field of view of 78.2 degrees and a 264×264 image size to match the calibration parameters of the bronchoscope camera.
Virtual-to-Real Registration
The virtual-to-real registration was performed using pyramid decomposition starting from level 3 and ending at level 1. To account for the difference in intensity characteristics between the imaging sources, the weighted normalized cross-correlation (12) was used as the objective function, with weights w u,v chosen as
w u,v =1 −I v ( u,v ) (15)
in order to emphasize dark areas, which tend to have more information in bronchoscopic video. The video frame, taken from a bronchoscopic procedure performed on h005 was first processed to remove the geometric barrel distortion from the lens to obtain the real image I r . In the virtual-to-real registration case, it is difficult to give ground truth locations as the location of the scope tip is in practice unknown. Without external localization, the quality of a good registration is somewhat qualitative in nature. FIG. 2 shows a sample of the registration results, with edges from the virtual image overlaid on the unregistered and registered real views. The results show that the alignment is qualitatively very satisfying.
Virtual-to-Virtual Registration
In the virtual-to-virtual registration case, the “real” image is actually a rendering generated at a specified location in the airway, but with all depth information discarded. The algorithm uses pyramid decomposition starting from level 3 and ending at level 1, and the weighted SSD objective function was used where the weights w u,v were chosen as in (15) as before.
FIG. 3 shows the “real” image I r prior to registration, the virtual image I v at the nearest reference site and the warped real image I r (W(u,v,Z;p)) after registration is complete.
X position
Y position
Z position
θα
θβ
θγ
Viewpoint
(mm)
(mm)
(mm)
(deg)
(deg)
(deg)
Initial
147.5
149.2
71.1
−20.2
−1.7
0
Reference
146.7
149.4
73.3
−7.3
5.1
−19.9
Site
Registered
147.6
149.0
73.9
−20.9
1.2
−3.2
Ground
147.1
148.9
73.8
−20.24
−1.8
−0.4
Truth
Error
0.6
0.1
0.5
−0.7
3.0
2.8
At least four different alternatives are available for registering the real and virtual sources in the case of bronchoscopy. These scenarios are outlined below:
1. Virtual-to-real registration: real-time or pre-recorded video images I r from a bronchoscope at an unknown location are registered to a set of endoluminal CT renderings I v and depth maps Z v .
2. Virtual-to-virtual registration: an endoluminal rendering I r with unknown location and with or without an associated depth map Z r is registered to a set of endoluminal CT renderings I v and depth maps Z v .
3. Real-to-real registration: real-time video images I r from an endoscope at an unknown location is registered to a set of previously recorded video images I v with known or estimated depth maps Z v .
4. Real-to-virtual registration: an endoluminal rendering I r with unknown position and with or without an associated depth map Z r is registered to a set of previously recorded video images I v with known or estimated depth maps Z v .
The application has far-reaching applications, particularly in the field of assisted endoscopy. The registration between a CT volume and real-time bronchoscopic video allows the fusion of information between the CT realm and the bronchoscope. This allows regions of interest (ROIs) defined only in the CT volume to be superimposed on the real video frame to assist the physician in navigating to these ROIs. Likewise, airway centerlines, branch labels and metric information such as distances to walls can be displayed on the video frame.
A natural extension of this concept is to other forms of endoscopy such as colonoscopy, where similar guidance information could be displayed on the registered colonoscopic image. Virtual-to-real registration can also be applied to pre-recorded endoscopic video, and opens the door to many post-processing options, such as mapping textural and color information available only in the endoscopic video onto the CT-derived surfaces to enable their visualization from viewpoints not available in the video alone.
An application of the real-to-real registration scenario that can be envisioned for this approach, is for aerial navigation. Satellite imagery, combined with topographic terrain information provides the known 3D environment, while real-time images from a mobile camera aboard an aircraft can be registered to this environment to give the aircraft's location and orientation without GPS or radar information. Similarly, this method also assists in ground-based robotic navigation within a known environment. Reference images and depth maps can be captured at known locations throughout the robot's working environment using a stereo camera setup, and a camera mounted on the robot can be registered to this set of images and depth maps.
REFERENCES
1. H. Minami, Y. Ando, F. Nomura, S. Sakai, and K. Shimokata, “Interbronchoscopist variability in the diagnosis of lung cancer by flexible bronchoscopy,” Chest 105(2), pp. 1658-1662, June 1994.
2. I. Bricault, G. Ferretti, and P. Cinquin, “Registration of real and CT-derived virtual bronchoscopic images to assist transbronchial biopsy,” IEEE Transactions On Medical Imaging, Vol. 17, No. 5, pp. 703-714, October 1998.
3. J. Helferty, Image-Guided Endoscopy and its Application To Pulmonary Medicine. PhD thesis, The Pennsylvania State University, 2002.
4. D. Deguchi, K. Mori, J. Hasegawa, J. Toriwaki, and H. Natori et al., “Camera motion tracking of real bronchoscope using epipolar geometry analysis and CT derived bronchoscopic images,” SPIE Medical Imaging 2002: Physiol. Func. from Multidim. Images A Clough and C. Chen (ed.), v. 4683, pp. 30-41, 2002.
5. B. Lucas and T. Kanade, “An iterative image registration technique with an application to stereo vision,” Proceedings of the International Joint Conference on Artificial Intelligence, pp. 674-679, 1981.
6. S. Baker and I. Matthews, “Equivalence and efficiency of image alignment algorithms,” Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition 1, pp. 1090-1097, 2001.
7. H.-Y. Shum and R. Szeliski, “Panoramic Image Mosaics,” Technical Report MSR-TR-97-23, Microsoft Research.
8. H.-Y. Shum and R. Szeliski, “Construction of panoramic image mosaics with global and local alignment,” International Journal of Computer Vision 36(2), pp 101-130 (2000)
9. T. Okatani and K. Deguchi, “Shape reconstruction from an endoscope image by shape from shading technique for a point light source at the projection center,” Computer Vision and Image Understanding 66, pp. 119-131, May 1997.
10. A. P. Kiraly, E. A. Hoffman, G. McLennan, W. E. Higgins, and J. M. Reinhardt, “3D human airway segmentation for virtual bronchoscopy,” SPIE Medical Imaging 2002: Physiology and Funct. from Multidim. Images, A. V. Clough and C. T. Chen, eds. 4683, pp. 16-29, 2002.
11. R. Swift, A. Kiraly, A. Sherbondy, A. L. Austin, E. A. Hoffman, G. McLennan, and W. E. Higgins, “Automatic axes-generation for virtual bronchoscopic assessment of major airway obstructions,” Computerized Medical Imaging and Graphics 26, pp. 103-118, March-April 2002. | Fast and continuous registration between two imaging modalities makes it possible to completely determine the rigid transformation between multiple sources at real-time or near real-time frame-rates in order to localize video cameras and register the two sources. A set of reference images are computed or captured within a known environment, with corresponding depth maps and image gradients defining a reference source. Given one frame from a real-time or near-real time video feed, and starting from an initial guess of viewpoint, a real-time video frame is warped to the nearest viewing site of the reference source. An image difference is computed between the warped video frame and the reference image. Steps are repeated for each frame until the viewpoint converges or the next video frame becomes available. The final viewpoint gives an estimate of the relative rotation and translation between the camera at that particular video frame and the reference source. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is directed to riser strings used with offshore rigs and vessels, keel joints used in various well operations, and to methods of their use.
[0003] 2. Description of Related Art
[0004] Wellbore operations from floating vessels typically utilize risers or tendons in a string that extends from the vessel to the sea floor. Such floating vessels include tension buoyant towers, compliant towers, and spars in which the structures extend well below the sea surface and are subjected to heave, pitch, and roll motion at the surface. The risers and tendons are connected to the sea floor and pass through openings in the keel or bottom portion of the vessels. The openings in the vessels constrain the pipe forming the risers or tendons when the vessel is moved laterally with respect to the sea floor connection.
[0005] In many prior systems a special section of riser called a “keel joint” is used adjacent the keel of the hull: to accommodate the bending loads where the riser leaves the support of the platform; to accommodate the relative vertical movement between the riser and the hull; and to protect the riser string and the hull from damage. Several prior keel joints are reinforced to carry the bending loads imposed on the riser by the pitch/heel motions of the hull relative to the riser as well as the bearing and wear loads imposed on the riser by the vertical and lateral motions of the hull relative to the riser. Lateral movement can produce bending of the riser pipe at the hull opening, or rotation of the riser pipe about the contact of the riser pipe with the edges of the opening. Bending of the pipe, which is normally under tension, can result in fatigue and wear at the opening.
[0006] The prior art includes a variety of patents directed to vessels, risers and keel joints, including, but not limited to, U.S. Pat. Nos. 4,634,314; 5,377,763; 5,628,586; 5,683,205; 6,422,791; 6,739,395; 6,746,182; 7,013,824; 7,144,048; and 7,217,067—all incorporated fully herein for all purposes. Certain prior systems include the use of thick-walled pipes with tapered ends. These thick, tapered wall sections have been machined from heavy forgings and can be relatively expensive. Another solution utilizes a sleeve member centralized within the vessel opening and a mud line or sea floor connection to receive the lower end of the pipe. The pipe is centralized within the sleeve but otherwise unattached to the sleeve. Other approaches use a centralizing, ring-like device and/or a ball joint, located between the side walls of the vessel opening and the pipe.
[0007] U.S. Pat. No. 5,683,205 discloses a joint that passes through the vessel opening and is connected to the sea floor with the pipe centralized within an outer sleeve with large elastomeric rings located at each axial end of the sleeve. U.S. Pat. No. 6,422,791 discloses a sleeve positioned around a riser pipe where the pipe penetrates the keel of the platform. The riser-to-sleeve attachment provides a load carrying capacity in both the axial and lateral direction (or reduced capacity in one of these directions) and permits flexibility for angular offsets between an outer sleeve and a riser pipe.
[0008] U.S. Pat. No. 7,217,067 discloses a riser joint keel assembly in which a tapered riser joint is connected to a larger diameter outer sleeve through a connection that allows the tapered section and outer sleeve to function as one unit. In the combined design, the outer sleeve provides the required sliding interface between the riser and the guide at the keel of the hull while also providing some of the bending compliance needed to transition from the riser supported in the hull to the riser unsupported below the hull. The tapered section also provides the remaining bending compliance needed for the transition. The connection between the tapered and sleeve sections is a forged, machined ring plate welded to the bottom end of the sleeve, which provides a base for either bolted or threaded type attachment points for the tapered riser joint below the ring plate and the internal riser joint that continues to the surface. In one aspect such an assembly for a floating offshore structure with a top-tensioned riser arrangement, includes a compliant riser keel joint assembly, including: a. an outer sleeve positioned inside two keel guides in the hull structure; b. an internal riser joint positioned in said sleeve and having a flange attached at the lower end; c. a centralizer mounted inside said outer sleeve adjacent the upper end and sized to receive said internal riser joint; d. a single, tapered riser joint positioned below said internal riser joint; and e. means for connecting the lower end of said internal riser joint to the upper end of said single-tapered riser joint, including i. said internal riser joint having a threaded lower end; ii. a flange attached to the upper end of said tapered riser joint; and iii. a machined ring attached to said sleeve, said ring having a threaded bore sized to threadably receive the internal riser joint and providing the attachment point for the flange on the tapered riser joint.
[0009] U.S. Pat. No. 7,013,824 discloses a riser centralizer for transferring lateral loads from the riser to a platform hull with a keel centralizer mounted on a keel joint. The keel centralizer is received within a keel guide sleeve secured in a support mounted at the lower end of the platform hull. The keel centralizer includes a nonmetallic composite bearing ring having a radiused peripheral profile for minimizing contact stresses between the keel centralizer and the keel guide sleeve in extremes of riser and platform motion. The internal surface of the keel guide sleeve is clad with a corrosion resistant alloy and coated with a wear resistant ceramic rich coating. In one aspect, there is keel centralizer that includes: a. a flat keel centralizer body having a central bore extending through said body; b. the keel centralizer body including a circumferential flange member defining the perimeter thereof; c. at least one opening extending through the keel centralizer body; d) a bearing ring mounted on the flange member; and e) a keel sleeve mounted in a keel support frame, the keel sleeve being adapted for slidably receiving the keel centralizer body, and wherein the keel sleeve is clad with a corrosion resistant material.
[0010] U.S. Pat. No. 6,746,182 discloses keel joint assemblies that permit a degree of rotational movement of a riser within the keel of a floating vessel and greatly reduce the amount of stress and strain that is placed upon the riser, as well. Keel joint assemblies described provide a limiting joint between the riser and the keel opening that permits some angular rotation of the riser with respect to the floating vessel. Additionally, the limiting joint permits the riser to move upwardly and downwardly within the keel opening, but centralizes the riser with respect to the keel opening so that the riser cannot move horizontally with respect to the keel opening. In certain embodiments, the limiting joint is provided by a single annular joint that allows that riser to move angularly with respect to the can. In some embodiments, the keel joint assembly incorporates a cylindrical stiffening can that radially surrounds a portion of the riser and is disposed within the keel opening. In these embodiments, a flexible joint is provided between the can and the riser. Supports or guides may be used to retain the can within the keel opening. In one aspect, in floating platform, there is: a hull having a bottom and a deck spaced above the bottom; a riser opening extending generally vertically through the hull from the bottom to the deck; a riser extending through the riser opening; a landing profile in the riser opening adjacent to the bottom of the hull; a guide sleeve having an engagement profile that lands and locks on the landing profile for movement with the hull; and a collar being located with the guide sleeve and having a flex member having a central passage through which the riser extends, the flex member being supported by the guide sleeve adjacent to the bottom of the hull, the flex member being movable axially relative to an axis of the riser and allowing angular movement of the guide sleeve relative to the riser.
[0011] U.S. Pat. No. 6,422,791 discloses an attachment that extends between an outer sleeve and an inner riser pipe where the pipe penetrates the keel of a platform. In one version, the attachment is a conically-shaped with a small diameter ring that engages the riser pipe and a large diameter ring that engages the outer sleeve. This attachment has elements that are very flexible in bending but relatively stiff and strong in axial load. Other versions include flat rings where lateral load is taken directly into tension and compression in the beams, allowing for relatively high lateral load transfer. Both the conically-shaped attachment and the flat ring have a number of variations that provide low bending stiffness but high axial stiffness of the elements. Depending on whether resistance to axial loads, lateral loads, or resistance to combination of both loads is desired, the attachment and the flat ring may be used alone or in combination. Other variations of the device provide two opposing conical shaped attachments or a conical and flat ring attachment installed together to provide load capability in both axial and lateral directions while still providing angular flexibility. In one aspect there is a riser joint for a riser extending between a floating vessel and a sea floor, the riser joint including: a tubular member having an axis; a sleeve surrounding a portion of the tubular member and having an upper end, a lower end, and a sleeve axis that substantially aligns with the axis of the tubular member; a metal upper element adjacent to the upper end of the sleeve, and having a first portion mounted to the sleeve, and a second portion mounted to the tubular member, wherein the first and second portions of the upper element are axially spaced apart; a metal lower element adjacent to the lower end of the sleeve, and having a first portion mounted to the sleeve, and a second portion mounted to the tubular member, wherein the first and second portions of the lower element are axially spaced apart; and wherein the upper and lower elements have apertures therein between the first and second portions to allow angular and radial flexibility of the tubular member relative to the sleeve and resist axial motion of the tubular member relative to the sleeve.
[0012] U.S. Pat. No. 4,634,314 discloses composite marine riser system which, in certain aspects, include tubular marine riser sections formed by a wound or woven filament-resin matrix tubular body having a modulus of elasticity in tension of about 27,000,000 psi or greater utilizing carbon or boron for the filament material. The riser sections may be provided with end couplings secured to the tubular body for forming a riser system wherein the tensile strength or load bearing capacity of each section and its hydrostatic collapse resistance may be selectively determined by its position in the riser system. The riser sections may be provided with cylindrical collapse resisting ribs defining spaced buoyancy chambers filled with low density material contained by an outer shell formed of a glass or aramid fiber-resin matrix composite having a lower modulus of elasticity in tension than the primary load bearing tubular member. An inner abrasion and fluid impervious sleeve is disposed within the tubular body but is not bonded thereto. Multiple conduit riser sections may be utilized as anchoring members for a floating platform and the like. In one aspect there is a marine riser for use in drilling or production of hydrocarbons from a subsea formation including: elongated tubular body means constructed of a composite of elongated filaments of a material in a resin matrix having a modulus of elasticity not less than about 27.times.10.sup.6 psi, said filaments being bonded in a resin matrix to form a load bearing member of the tubular body means having an elastic elongation strain characteristic under stress in tension not substantially greater than steel; and coupling means at opposite ends of the tubular body means for coupling the riser to a member for transmission of tensile loads through the tubular body means between said ends.
BRIEF SUMMARY OF THE PRESENT INVENTION
[0013] The present invention, in at least certain aspects, provides a keel joint protector with a body made of flexible material, a central open bore through the body, and the body having a plurality of spaced-apart energy management zones therein for diffusing a force applied to a particular part of the body.
[0014] A force or load that encounters an energy management zone in an apparatus according to the present invention is defocused in the sense that the force or load goes around the zone Thus a concentrated or point-applied force or load is diffused and distributed.
[0015] In certain aspects, the present invention teaches a keel with: a riser pipe; a plurality of keel joint protectors on the riser pipe including at least one pair of keel joint protectors,; each of the plurality of keel joint protectors having a body made of flexible material, a central open bore through the body, the body having a plurality of spaced-apart energy management zones; a support ring between each pair of keel joint protectors; and, optionally, a protective shell over the keel joint protectors and support rings.
[0016] In certain aspects, the present invention teaches methods for protecting a hull of a rig adjacent a keel joint, the keel joint extending through an opening in the hull, the methods including: positioning a keel joint with respect to a hull, the keel joint extending through an opening in the hull, the keel joint like any disclosed herein according to the present invention, e.g., one having a body made of flexible material, a central open bore through the body, the body having a plurality of spaced-apart energy management zones, and contacting the hull with the keel joint so that a force is applied to the body of the keel joint and the force's effects on the hull is diffused.
[0017] The present invention, in certain embodiments, discloses centralizers for centralizing a tubular, e.g. in a wellbore or in another tubular, the centralizers, in certain aspects, including: a body made of flexible material; a central open bore through the body; the body having a plurality of spaced-apart energy management zones.
[0018] Accordingly, the present invention includes features and advantages which are believed to enable it to advance keel joint and centralizer technology. Characteristics and advantages of the present invention described above and additional features and benefits will be readily apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments and referring to the accompanying drawings.
[0019] Certain embodiments of this invention are not limited to any particular individual feature disclosed here, but include combinations of them distinguished from the prior art in their structures, functions, and/or results achieved. Features of the invention have been broadly described so that the detailed descriptions that follow may be better understood, and in order that the contributions of this invention to the arts may be better appreciated. There are, of course, additional aspects of the invention described below and which may be included in the subject matter of the claims to this invention. Those skilled in the art who have the benefit of this invention, its teachings, and suggestions will appreciate that the conceptions of this disclosure may be used as a creative basis for designing other structures, methods and systems for carrying out and practicing the present invention. The claims of this invention are to be read to include any legally equivalent devices or methods which do not depart from the spirit and scope of the present invention.
[0020] What follows are some of, but not all, the objects of this invention. In addition to the specific objects stated below for at least certain embodiments of the invention, there are other objects and purposes which will be readily apparent to one of skill in this art who has the benefit of this invention's teachings and disclosures. It is, therefore, an object of at least certain preferred embodiments of the present invention to provide the embodiments and aspects listed above and:
[0021] New, useful, unique, efficient, non-obvious keel joints, vessels with such keel joints, and methods of their use; and
[0022] Such systems with riser protectors with a plurality of energy management zones.
[0023] The present invention recognizes and addresses the problems and needs in this area and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one of skill in this art who has the benefits of this invention's realizations, teachings, disclosures, and suggestions, various purposes and advantages will be appreciated from the following description of preferred embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent's object to claim this invention no matter how others may later attempt to disguise it by variations in form or additions of further improvements.
[0024] The Abstract that is part hereof is to enable the U.S. Patent and Trademark Office and the public generally, and scientists, engineers, researchers, and practitioners in the art who are not familiar with patent terms or legal terms of phraseology to determine quickly from a cursory inspection or review the nature and general area of the disclosure of this invention. The Abstract is neither intended to define the invention, which is done by the claims, nor is it intended to be limiting of the scope of the invention or of the claims in any way.
[0025] It will be understood that the various embodiments of the present invention may include one, some, or all of the disclosed, described, and/or enumerated improvements and/or technical advantages and/or elements in claims to this invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0026] A more particular description of embodiments of the invention briefly summarized above may be had by references to the embodiments which are shown in the drawings which form a part of this specification. These drawings illustrate certain preferred embodiments and are not to be used to improperly limit the scope of the invention which may have other equally effective or legally equivalent embodiments.
[0027] FIG. 1 is a side schematic view of a system according to the present invention.
[0028] FIG. 2A is a perspective view of a pipe used in the keel joint according to the present invention shown in FIG. 2B .
[0029] FIG. 2B is a perspective view of a keel joint according to the present invention.
[0030] FIG. 2C is an exploded perspective view of the keel joint of FIG. 2B .
[0031] FIG. 3A is a side view of a protector according to the present invention.
[0032] FIG. 3B is a top view of the protector of FIG. 3A .
[0033] FIG. 4A is a side view of an inner support of the protector of FIG. 3A .
[0034] FIG. 4B is a top view of the inner support of FIG. 4A .
[0035] FIG. 5A is a side view of an outer support of the protector of FIG. 3A .
[0036] FIG. 5B is a top view of the outer support according to the present invention of FIG. 5A .
[0037] FIG. 6A is a side view of an eyebolt mounting block of the protector of FIG. 3A .
[0038] FIG. 6B is a front view of the eyebolt mounting block of FIG. 6A .
[0039] FIG. 7A is a side view of a safety cable mounting block of the protector of FIG. 3A .
[0040] FIG. 7B is a front view of the safety cable mounting block of FIG. 6A .
[0041] FIG. 8A is a top view of a mounting bracket of the protector of FIG. 3A .
[0042] FIG. 8B is a side view of the mounting bracket of FIG. 8A .
[0043] FIG. 8C illustrates top views of various shapes of brackets for supports according to the present invention.
[0044] FIG. 9A is a side view of a mounting block of the protector of FIG. 3A .
[0045] FIG. 9B is a top view of the mounting block of FIG. 9A .
[0046] FIG. 10 is a perspective view of a body part of a protector according to the present invention.
[0047] FIG. 10A illustrates top views of various shapes for an energy management zone according to the present invention.
[0048] FIG. 11A is a side view of a protector according to the present invention.
[0049] FIG. 11B is a side view of locking bars according to the present invention for securing together two protectors according to the present invention.
[0050] FIG. 11C is a side view of a protector according to the present invention.
[0051] FIG. 11D is a top view (or bottom view) of the protectors of FIGS. 11A and 1C .
[0052] FIG. 11E is an end view of half of one of the protectors of FIG. 11D .
[0053] FIG. 11F is a schematic view of the protector half of FIG. 11E .
[0054] FIG. 11G is a schematic view of the protector half of FIG. 11E .
[0055] FIG. 11H is a schematic view of the protector half of FIG. 11E .
[0056] FIG. 12A is a perspective view of the protector according to the present invention.
[0057] FIG. 12B is a cross-section view of the protector of FIG. 12A .
[0058] FIG. 13A is a perspective view of the protector according to the present invention.
[0059] FIG. 13B is a cross-section view of the protector of FIG. 13A .
[0060] FIG. 14A is a top view of a protector according to the present invention.
[0061] FIG. 14B is a side cross-section view of the protector of FIG. 14A .
[0062] FIG. 14C is a side view of supports of the protector of FIG. 14A .
[0063] FIG. 14D is a top view of the supports of FIG. 14C .
[0064] FIG. 15 is a side view of a centralizer according to the present invention on a tubular member.
[0065] Presently preferred embodiments of the invention are shown in the above-identified figures and described in detail below. It should be understood that the appended drawings and description herein are of preferred embodiments and are not intended to limit the invention or the appended claims. On the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims. In showing and describing the preferred embodiments, like or identical reference numerals are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.
[0066] As used herein and throughout all the various portions (and headings) of this patent, the terms “invention”, “present invention” and variations thereof mean one or more embodiments, and are not intended to mean the claimed invention of any particular appended claim(s) or all of the appended claims. Accordingly, the subject or topic of each such reference is not automatically or necessarily part of, or required by, any particular claim(s) merely because of such reference. So long as they are not mutually exclusive or contradictory any aspect or feature or combination of aspects or features of any embodiment disclosed herein may be used in any other embodiment disclosed herein.
DETAILED DESCRIPTION OF THE INVENTION
[0067] FIG. 1 illustrates a floating drilling vessel 10 according to the present invention which has a hull 12 in water up to a waterline 14 . A riser string 20 extends from a deck 16 into the water. A derrick 18 , shown partially, on the deck 16 is a typical wellbore operations derrick. Typical well operations equipment E 1 , E 2 , E 3 , E 4 , E 5 is used with the riser string (any suitable known equipment for any wellbore operations). The riser string pivot 22 permits the riser string 20 to pivot.
[0068] A keel joint 30 according to the present invention is located in the riser string 20 for contacting sides 24 of a moonpool of the hull 12 . The keel joint 30 may be any keel joint according to the present invention disclosed herein.
[0069] FIGS. 2A and 2B shows a keel joint 40 according to the present invention which has a plurality of protectors 50 according to the present invention on a riser 44 covered by a shell 42 . The shell 42 has two halves, 42 a and 42 b (one shown in FIGS. 2B , 2 C), which are bolted, fastened, welded, and/or glued in place. Optionally, the shell 42 is a single hollow cylinder. Rings 54 between the protectors 50 hold together two halves, 50 a, and 50 b, of each protector 50 . In one aspect, each pair of halves 50 a, 50 b are bolted together on the riser 44 . The rings 54 (which may be split rings secured together) carry the weight of the protectors and hold them in position.
[0070] The protectors 50 may be any protector disclosed herein according to the present invention. Any desired number of protectors 50 may be used on the riser 44 (as is true for the number of protectors for any keel joint according to the present invention). In certain aspects according to the present invention, a riser or pipe of a keel joint is completely covered with protectors (e.g. as in FIG. 2B ), while in other aspects only one protector is used or two or more spaced-apart protectors are used. In certain aspects the protectors are two-piece with the two pieces installed around the riser and secured together. When connected together, the protectors have a central open bore through which the riser passes. In other aspects, the protectors are a single integral item with a central bore in one aspect, molded in place on a tubular such as a riser.
[0071] As is true of any keel joint according to the present invention, the protectors 50 , the rings 54 , inner and outer supports, and/or the shells 42 may be made of plastic, foam, rubber, wood, metal (including, but not limited to, brass, bronze, steel, stainless steel, aluminum, aluminum alloy, zinc, zinc alloy), composite, fiberglass, nylon, and/or KEVLAR (TRADEMARK) material. In certain aspects the bodies of protectors like the protectors 50 (and any protector according to the present invention) are made from flexible material, e.g., but not limited to, flexible urethanes and polyurethanes. Optionally, the shell 42 may be molded in place on a riser or formed of two (or more) parts secured together on a riser. Optionally a protector 50 (and any protector disclosed herein) can be a single integral item.
[0072] As shown in FIG. 2C the protectors 50 each have a series of cells, holes, zones and/or openings 58 . Any such zones, cells, etc. disclosed herein according to the present invention may be used. The rings 54 may have grooves or recesses for receiving and holding a protector or part of a protector.
[0073] FIGS. 3A and 3B show a protector 100 according to the present invention which may be used in any keel joint according to the present invention. The protector 100 has a central open bore 100 b therethrough. The protector 100 has two halves 101 , 102 releasably secured together by securing together lips 120 s with bolts 103 , threadedly secured in corresponding holes 108 a in nuts 108 each on an inner support 120 . An outer support 140 is spaced-apart from the inner support 120 . Optionally, the two halves 101 , 102 are also releasably held together by one, two, or more members 105 each secured by bolts 106 /nuts 107 to an outer support 140 through holes 140 a in lips 140 p. The lips 140 p wrap around and are adjacent edges of the halves 101 , 102 . The members 105 may be any suitable rigid (e.g. but not limited to metal plates or bars) or flexible member (e.g., but not limited to springs, corrugated metal, cables, etc.). As shown in FIG. 3B , the members 105 are pieces of flexible stainless steel cable. Optionally, the bolts 103 are deleted. Optionally, the bolts 103 are deleted and bolts (not shown) at the location of the members 105 releasably hold the two halves 101 , 102 together. The bolts 103 are accessible through channels 109 .
[0074] As is true of any keel joint disclosed herein according to the present invention, the inner support 120 and any inner supports and outer supports) can be made of any suitable material, including, but not limited to, metal, plastic, composite or fiberglass. In certain aspects an optional interior ridge member 128 is provided on each inner support 120 for contacting a riser on which a protector with such inner supports is installed. In certain aspects, the ridge members 128 are made of non-conductive material that does not conduct electricity, e.g., but not limited to fiberglass, plastic, foam, or polyurethane to reduce or inhibit galvanic corrosion. Optionally ridge members, with recesses 120 , inhibits or prevents metal/metal contact between a riser (or other tubular) and metal of the protector 100 (especially in the event of corrosion of a metal part). This also prevents metal/metal corrosion. The recesses 120 provide space into which material under load can move.
[0075] Channels 109 provide access to bolts 103 . Eyebolt holes 111 are adjacent corresponding holes 112 a in eyebolt mounting blocks 112 . The eyebolt mounting blocks provide lift points and attachment points. The bolts 106 extend through the outer supports 140 and threadedly mate with corresponding holes 113 a in mounting blocks 113 which are secured to the outer supports (e.g. with epoxy and/or welding). Openings or gaps 120 p permit material flow during production process, e.g. a molding process, to produce the halves 101 , 102 . Material can remain within the gaps following production.
[0076] Optionally bodies 101 a, 102 a of the halves 101 , 102 are formed or made with one, two, three, four, five, six or more inner retaining brackets 114 . In one aspect, these brackets 114 are completely encased within material (e.g. plastic, rubber, foam, fiberglass or composite) that is used to make the halves 101 , 102 . The inner support 120 may be connected to the outer support 140 or, as shown, the two are not connected together (other than by body material between them); thus desirable movement of the inner support with respect to the outer support is possible, which facilitates energy management. The mounting blocks 108 are shown in FIGS. 4A and 4B .
[0077] Each half 101 , 102 has a plurality of energy management zones 161 , 162 , 163 , 164 defined by ribs 165 , 166 , 167 , 174 and by parts 168 , 169 , 171 , 172 , 173 of the bodies 101 a, 102 a. It is within the scope of the present invention for the energy management zones to each have a floor F 1 , F 2 , F 3 , F 4 , i.e., these zones are not holes or channels which extend all the way through the bodies 101 , 102 from one side to the other or from one end to the other. These floors F 1 -F 4 are below a surface of the bodies 101 , 102 . The depth of each energy management zone can be the same or, according to the present invention, depths of different zones can be different. In one particular embodiment, the energy management zones 162 are three inches deep with a two degree side taper in a body that is 28 inches wide (“w”, FIG. 3A ), 49.3 inches long (“l,” FIG. 3A ) and about 10 inches thick (“t,” FIG. 3B ). In such a body, the energy management zones 163 are 11 inches deep, the energy management zones 161 and 164 are 13 inches deep, the ribs 165 , 167 are about 1.7 inches thick, the ribs 174 are about 1.8 inches thick.
[0078] The outer support 140 can be within the body of the protector or, as shown in FIG. 3B , can be on the outside of the protector. The inner support 120 can, as shown in FIG. 3B , be within the protector, or can be outside.
[0079] FIG. 10 shows a protector half 200 according to the present invention for use with any protector disclosed herein according to the present invention. The half 200 has a body 202 with a plurality of energy management zones 211 , 212 , 213 , 214 ; ribs 216 , 217 , 218 ; body parts 221 , 222 , 223 , 224 and ends 225 , 226 . An inner support 238 (like any inner support disclosed herein) with or without brackets (like the brackets 114 ) is spaced-apart from an outer support 240 , like any outer support disclosed herein, with or without brackets (like the brackets 114 ). The inner support 238 has lips 238 a which are adjacent and wrap around edges of the body 202 . The outer support 240 has lips 240 a that are adjacent and wrap around edges of the body 202 . FIG. 10 shows the top of the body 202 . The bottom (not shown) has corresponding energy management zones which are the same as the energy management zones, ribs, body parts and ends shown for the top. The energy management zones of top and bottom all have floors and, e.g., the energy management zones 212 on the top are spaced-apart from the corresponding zones 212 on the bottom by part of the body 202 so that corresponding top and bottom zones are not in communication with each other (i.e., fluid cannot flow from a top zone to a corresponding bottom zone). In one aspect the protector half 200 is made of polyurethane.
[0080] In use, the various energy management zones of the protector 200 (and of any protector according to the present invention with a plurality of adjacent energy management zones) act as deformable crumple zones which absorb an impact and facilitate the distribution of the force of an impact from an impact point or area to other portions of the protector. In certain methods of use, according to the present invention, of protectors according to the present invention the protectors are secured to the riser adjacent moonpool sides with the protector seams (the plane at which ends of adjacent protector halves meet) perpendicular to the moonpool sides so that relatively large body parts (e.g. body parts 222 , FIG. 10 ) will abut the moonpool sides in the event of keel-joint/moonpool-side contact. In certain aspects with such a positioning of a protector, force initially applied at such a body part (e.g. the body parts 222 , 224 , FIG. 10 ) is distributed over a portion of the protector which includes additional parts of the body in addition to the body part at which the initial impact occurs. In certain aspects it is desirable that the protector be positioned so that a point of impact will be at or near a protector part at which protector material extends all the way from the protector outer surface to the protector inner surface (e.g. see adjacent body parts 222 , 224 ; and rib 216 and part 221 ). In one particular aspect such an initial impact is distributed over, about one fourth of the entire protector's body (e.g., with a protector that has an outer circumference of about one hundred fifty seven inches, and a height of about twenty-six inches). Thus by using body parts (like the body parts 221 , 222 , 224 , FIG. 10 ) with ribs (like the ribs 217 , 218 , FIG. 10 ) localized contact forces are distributed over a larger area than the area of initial contact. In certain particular cases in which a distribution to one-fourth of the protector is achieved, no brackets (like the optional brackets 114 ) are used. By using such brackets, it is believed greater and more efficient, force distribution will be achieved and separation of a body, e.g. separation of a urethane body from steel inner and outer supports, will be inhibited or reduced.
[0081] In one aspect of the protector 200 , zone depth in inches is as follows: zones 211 , 11 inches; zones 212 , 13 inches; zones 213 13 inches; and zones 214 , 3 or 11 inches.
[0082] It is within the scope of the present invention to employ energy management zones which, viewed from above, are generally triangular (like the zones 211 - 214 , FIG. 10 ) with bases of adjacent zones adjacent each other, with apices of adjacent zones opposite each other (see apex a and apex b, FIG. 10 ). Optionally, each pair of generally triangular zones is spaced-apart from each other pair by a relatively large body part (e.g. see body parts 222 , 224 , FIG. 10 ) or by a relatively large body part and a rib (e.g., see body part 221 and rib 216 , FIG. 10 ). Optionally, a relatively large body part has a plurality of spaced-apart ribs radiating from it (e.g. see ribs 217 and 218 with respect to body part 222 , FIG. 10 ; see, ribs 217 , 216 , 217 with respect to body part 221 , FIG. 10 ). Optionally, at an area of expected impact energy management zones are adjacent a relatively large body mass (e.g. see zones 212 , 211 , 214 , 213 adjacent a mass including body parts 222 , 224 , FIG. 10 ), a relatively large mass which extends fro an outer surface of the body to an inner surface thereof. It is within the scope of the present invention for the shape of the energy management zones, as viewed from above, to be any suitable shape, including, but not limited to, square, rectangular, pentagonal, hexagonal, or seven-sided, with or without rounded-off corners, e.g., as those shown in FIG. 10A .
[0083] The brackets 114 , shown in FIGS. 8A , 8 B and 3 B, serve as mechanical anchors for the body material of a protector half. It is within the scope of the present invention for these anchors to be any suitable shape or size so long as they protrude from their respective support sufficiently to anchor the body to the support. FIG. 8C shows several alternative shapes for these anchoring brackets, as viewed from above. In use within a body of a protector, a portion, in some cases a substantial portion, of these anchoring brackets is encased in the material of the body of a protector.
[0084] Any energy management zone of any keel joint or centralizer according to the present invention may extend all the way through the protector or centralizer body. For protectors according to the present invention or centralizers according to the present invention, halves thereof may be secured together by frangible members and/or shear bolts which break under a certain predetermined load.
[0085] In certain aspects, a keel joint according to the present invention has a body having a first primary body part, a second primary body part, a third primary body part, and a fourth primary body part (primary body parts like the parts 222 , FIG. 10 ); the plurality of spaced-apart energy management zones (e.g. as in the protector 200 ) including a plurality of first zones, a plurality of second zones, a plurality of third zones, and a plurality of fourth zones; the plurality of first zones projecting inwardly of the body from the first primary body part (e.g. the zones 211 , 212 , 213 , 214 , FIG. 10 ) and the plurality of second zones projecting inwardly of the body from the second primary body part (e.g. the zones 211 , 212 , 213 , 214 , FIG. 10 ); the plurality of third zones projecting inwardly of the body from the third primary body part (e.g. the zones 211 , 212 , 213 , 214 , FIG. 10 ); and the plurality of fourth zones projecting inwardly of the body from the fourth primary body part (e.g. the zones 211 , 212 , 213 , 214 , FIG. 10 ). In such a keel joint the body has a central open bore therethrough (e.g. bore 100 , FIG. 3B or a bore formed between two halves as shown in FIG. 10 ); an inner support (e.g. support 120 , FIG. 3B or support 238 , FIG. 10 ); an outer support (e.g. support 140 , FIG. 3B or support 240 , FIG. 10A ); the inner support spaced-apart from the outer support; and a secondary body part extending from each primary body part to an inner support (e.g. the part 224 , FIG. 10 or the rib 166 , FIG. 3B ). In such a keel joint, in certain aspects, there is a bracket in each primary part and encased therein (e.g. a bracket 114 on the support 140 , FIG. 3B ); and a bracket in each secondary part and encased therein (e.g. a bracket 114 on the support 120 , FIG. 3B ).
[0086] In certain aspects, a keel joint according to the present invention has a first half having a first inner support and a first outer support and a second half having a second inner support and a second outer support (e.g., the two halves 101 , 102 , FIG. 3B ); each inner support having a first end and a second end; a first inner lip on the first end of the first inner support adjacent an edge of the first body half, a second inner lip on the second end of the first inner support each adjacent an edge of the first body half, a third inner lip on the second inner support adjacent an edge of the second body half, a fourth inner lip on the second inner support adjacent an edge of the second body half (see, e.g., lips 120 s, FIG. 3B ); a first outer lip on the first outer support adjacent an edge of the first body half, a second outer lip on the first outer support adjacent an edge of the first body half, a third outer lip on the second outer support adjacent an edge of the second body half, and a fourth outer lip on the second outer support adjacent an edge of the second body half (outer lips e.g. the lips 140 p, FIG. 3B ).
[0087] In certain aspects, a keel joint according to the present invention has a plurality of energy management zones, each energy management zone having a depth and a plurality of adjacent energy management zones having different depths (e.g. the zones from a one o'clock to a three o'clock position as viewed in FIG. 11F ). In certain aspects a keel joint according to the present invention has a plurality of the spaced-apart energy management zones each having portions therein with different depths (e.g. the zones 321 with zones 326 therein, FIGS. 11F and 11G ).
[0088] FIGS. 11A-11C show an exploded view of two protectors 300 , 302 according to the present invention (which may be any protector according to the present invention) which are joined together by pins 304 or bars which have portions that extend with a friction fit into holes 306 , 308 of the adjacent protectors 300 , 302 .
[0089] FIG. 11D shows an end view of one embodiment of the protector 302 . The protector 302 as shown in FIGS. 11D and 11E has two halves 311 , 312 each with an inner support 313 and an outer support 314 , each with a plurality of anchor brackets 315 and bodies 311 a, 312 a, respectively anchored to the brackets 315 and made, in one aspect, of polyurethane which is bonded to the inner surfaces of the supports 313 , 314 . A plurality of spaced-apart ridge members 316 made of polyurethane or some other non-electrical-conductor material encircle the circle formed by inner surfaces of the inner supports 313 . The halves 311 , 312 may be releasably secured together around a riser with any securement structure disclosed herein.
[0090] In one aspect the protector halves 311 , 312 have a plurality of energy management zones, 321 , 322 , 323 , 324 adjacent each other (with the zones 322 , 323 , 325 , and 326 projecting further downwardly from a floor of zones 321 ). As is true for any embodiment hereof, the zones may be of the same or of different depths, and/or as in certain aspects, the zone sides are tapered (as may be any zone of any protector disclosed herein), e.g., but not limited to, with a two degree taper. FIGS. 11F-11H provide a key for zone depth for one particular embodiment of the protector 300 (the end of the protector 300 opposite the end shown in FIGS. 11D and 11E has corresponding zones). The zones blacked out in FIG. 11F are three inches deep; those in FIG. 11G , twelve-and-a-half inches deep; and those in FIG. 11H , eleven inches deep. Some (not all) of the corresponding zones are shown in FIG. 11C . As is true for any keel joint according to the present invention or centralizer according to the present invention, energy management zones reduce the amount of material in a body and facilitate the distribution of a focused or what is essentially a point load over a larger area and mass.
[0091] FIGS. 14A and 14B show a protector 400 according to the present invention which has two halves 401 , 402 each with a body 401 a, 402 a, respectively. Each half has an inner support 403 with body anchor brackets 404 and securement structure 405 for releasably securing the two halves 401 , 402 together. Recesses 406 provide access to the securement structures 405 . Each body half 401 , 402 has a plurality of spaced-apart energy management zones 407 and 408 . Corresponding top and bottom zones (as viewed in FIG. 14B ) have floors (e.g. see the floors 407 f, 407 g, FIG. 14B ) which are spaced-apart by a certain amount of the mass of the body of the protector. As shown the zones 407 are all of the same depth as are the zones 408 and the depth of all zones is the same. As with any protector according to the present invention, the zone depth for any zone may be a percentage of the total height (height h as viewed in FIG. 14B ) which is, in certain aspects, between 10 and 45% of the height; in certain aspects with individual zones with depths of 10.7% of h, 39.2% of h, and 44.6% of h; and, in certain aspects, with at least two inches between the floors of corresponding zones.
[0092] FIGS. 12A and 12B show a keel joint 500 according to the present invention which includes a plurality of spaced-apart protectors 502 on a riser pipe 504 with rings 506 between the protectors 502 . A protective shell 508 (only half shown in FIG. 12A ) is secured around the protectors 502 . The rings 506 , secured to the riser pipe 504 , hold the protectors in place on the riser pipe 504 and support the weight of the protectors.
[0093] FIGS. 13A and 13B show a keel joint 600 according to the present invention which includes a plurality of spaced-apart protectors 602 on a riser pipe 604 with spacers 606 between the protectors 602 . A protective shell 608 (only half shown in FIG. 13A ) is secured around the protectors 602 . As is true for any embodiment herein, rings, like the rings 606 can be deleted either so the protectors have empty space between them or so that protectors are positioned in contact with each other. Radially-oriented holes 610 extend through the protectors 602 .
[0094] In certain particular aspects a structure according to the present invention (any disclosed herein) is used as a centralizer on a wellbore tubular (pipe, casing, tubing). FIG. 15 shows a centralizer 700 according to the present invention on a tubular member 702 . The centralizer 700 may have the structure, materials, and details of any protector described above or disclosed herein.
[0095] A centralizer according to the present invention may be used, e.g., in place of centralizers as disclosed in U.S. Pat. Nos. 7,159,668; 6,435,275; 5,908,072; 5,881,810; 5,575,333; 5,261,488; 5,238,062; 5,095,981; 4,984,633; 4,794,986; 4,787,458; 3,963,075; 3,528,499; and 3,052,310.
[0096] The present invention, therefore, provides in at least some, but necessarily all, embodiments: keel joint protector including: a body made of flexible material, a central open bore through the body, and the body having a plurality of spaced-apart energy management zones therein for diffusing a force applied to a particular part of the body. Such a system may include one or some, in any possible combination, of the following: wherein the flexible material is polyurethane; the body having a central open bore therethrough, an inner support, an outer support, and the inner support spaced-apart from the outer support; wherein the body is molded onto the inner support and the outer support; wherein the inner support has a plurality of spaced-apart openings therethrough, said openings containing a portion of the flexible material that makes the body; a plurality of brackets on the inner support projecting outwardly from the inner support into the body, a plurality of brackets on the outer support projecting inwardly from the outer support into the body, and a portion of each bracket encased in the flexible material of the body; the body having a first primary body part, a second primary body part, a third primary body part, and a fourth primary body part, the plurality of spaced-apart energy management zones including a plurality of first zones, a plurality of second zones, a plurality of third zones, and a plurality of fourth zones, the plurality of first zones projecting inwardly of the body from the first primary body part, the plurality of second zones projecting inwardly of the body from the second primary body part, the plurality of third zones projecting inwardly of the body from the third primary body part, and the plurality of fourth zones projecting inwardly of the body from the fourth primary body part; the body having a central open bore therethrough, an inner support, an outer support, the inner support spaced-apart from the outer support, and a secondary body part extending from each primary body part to an inner support; a bracket in each primary part and encased therein, and a bracket in each secondary part and encased therein; wherein the energy management zones extend down into the body at different depths; an inner layer of flexible material on the inner support, and the central open bore defined by the inner layer; a plurality of spaced-apart gaps in the inner layer; the body made of two halves connected together including a first half and a second half; the first half having a first inner support and a first outer support, the second half having a second inner support and a second outer support, each inner support having a first end and a second end, a first inner lip on the first end of the first inner support adjacent an edge of the first body half, a second inner lip on the second end of the first inner support each adjacent an edge of the first body half, a third inner lip on the second inner support adjacent an edge of the second body half, a fourth inner lip on the second inner support adjacent an edge of the second body half, a first outer lip on the first outer support adjacent an edge of the first body half, a second outer lip on the first outer support adjacent an edge of the first body half, a third outer lip on the second outer support adjacent an edge of the second body half, and a fourth outer lip on the second outer support adjacent an edge of the second body half; a first fastener connecting the first inner lip and the third inner lip, and a second fastener connecting the second inner lip and the fourth inner lip; a third fastener connecting the first outer lip and the third outer lip, and a fourth fastener connecting the second outer lip and the fourth outer lip; a first fastener connecting the first inner lip and the third inner lip, a second fastener connecting the second inner lip and the fourth inner lip, a third fastener connecting the first outer lip and the third outer lip, and a fourth fastener connecting the second outer lip and the fourth outer lip; each energy management zone having a depth; and a plurality of adjacent energy management zones having different depths; and/or a plurality of the spaced-apart energy management zones each has portions therein with different depths.
[0097] The present invention, therefore, provides in at least some, but necessarily all, embodiments: a keel joint protector including: a body made of flexible material, a central open bore through the body, the body having a plurality of spaced-apart energy management zones therein for diffusing a force applied to a particular part of the body, an inner support connected to the body, an outer support connected to the body, the inner support spaced-apart from the outer support, the inner support having a plurality of spaced-apart openings therethrough, said openings containing a portion of the flexible material, a plurality of brackets on the inner support projecting outwardly from the inner support into the body, a plurality of brackets on the outer support projecting inwardly from the outer support into the body, a portion of each bracket encased in the flexible material, the body made of two halves, including a first half and a second half, the first half connected to the second half with fasteners.
[0098] The present invention, therefore, provides in at least some, but necessarily all embodiments, a keel joint including: a riser pipe; a plurality of keel joint protectors on the riser pipe comprising at least one pair of keel joint protectors; each of the plurality of keel joint protectors comprising a body made of flexible material, a central open bore through the body, the body having a plurality of spaced-apart energy management zones therein for diffusing a force applied to a particular part of the body; a support ring between each pair of keel joint protectors; and a protective shell over the keel joint protectors and support rings.
[0099] The present invention, therefore, provides in at least some, but necessarily all embodiments, a method for protecting a hull of a rig with respect to a keel joint adjacent the hull, the keel joint extending through an opening in the hull, the method including: positioning a keel joint with respect to a hull, the keel joint extending through an opening in the hull, the keel joint comprising a body made of flexible material, a central open bore through the body, the body having a plurality of spaced-apart energy management zones therein for diffusing a force applied to a particular part of the body; and contacting the hull with the keel joint so that a force is applied to the body of the keel joint and said force is diffused in the body.
[0100] The present invention, therefore, provides in at least some, but necessarily all embodiments, a centralizer for centralizing a tubular, the centralizer including: a body made of flexible material, a central open bore through the body, and the body having a plurality of spaced-apart energy management zones therein for diffusing a force applied to a particular part of the body.
[0101] In conclusion, therefore, it is seen that the present invention and the embodiments disclosed herein and those covered by the appended claims are well adapted to carry out the objectives and obtain the ends set forth. Certain changes can be made in the subject matter without departing from the spirit and the scope of this invention. It is realized that changes are possible within the scope of this invention and it is further intended that each element or step recited in any of the following claims is to be understood as referring to the step literally and/or to all equivalent elements or steps. The following claims are intended to cover the invention as broadly as legally possible in whatever form it may be utilized. The invention claimed herein is new and novel in accordance with 35 U.S.C. §102 and satisfies the conditions for patentability in §102. The invention claimed herein is not obvious in accordance with 35 U.S.C. §103 and satisfies the conditions for patentability in §103. This specification and the claims that follow are in accordance with all of the requirements of 35 U.S.C. §112. The inventors may rely on the Doctrine of Equivalents to determine and assess the scope of their invention and of the claims that follow as they may pertain to apparatus not materially departing from, but outside of, the literal scope of the invention as set forth in the following claims. All patents and applications identified herein are incorporated fully herein for all purposes. What follows are some of the claims for some of the embodiments and aspects of the present invention, but these claims are not necessarily meant to be a complete listing of nor exhaustive of every possible aspect and embodiment of the invention. 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 screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words ‘means for’ together with an associated function. In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are including, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements. | A keel joint protector, which, in certain aspects, includes a body made of flexible material, a central open bore through the body, and the body having a plurality of spaced-apart energy management zones therein for diffusing a force applied to a particular part of the body. This abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims, 37 CFR 1.72(b). | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and apparatus for making photographic light-sensitive material wherein a photographic emulsion is coated on a support web, such as photographic film, Baryta paper and the like, and thereafter irradiated with microwave energy before cooling and setting to thereby concentrate the coating and decrease the overall drying time.
1. Description of the Prior Art
In the past, photographic film has been made by coating a light-sensitive emulsion on a web, cooling and setting the coating, and thereafter using ordinary air to dry the coating under controlled humidity conditions, and it is a natural tendency to try to increase the coating speed in order to enhance production capacity. Since the coating and drying steps in manufacturing a film are conducted in a continuous manner, if the web transport speed is increased to increase the coating speed, the drying time becomes shortened if the drying zone is constant in length. Generally speaking, if the drying capacity is constant, the degree of drying progress is proportional to the drying time, resulting in difficulty in achieving sufficient drying. For this reason, it is necessary to lengthen the drying zone corresponding to the rate of increase in the coating speed to accomplish sufficient drying. This is difficult to realize, however, in terms of both space and the cost of the added installation. To achieve sufficient drying, additional means must thus be provided to relieve the drying load in order to meet the needs of hgh speed coating.
To relieve such drying load, two methods have been proposed to provide a concentrated photographic emulsion prior to its application to the web. One method is to concentrate the photographic emulsion during its formation process, and thereafter various chemicals are added and mixed with the emulsion. In the other method, the emulsion is firstly mixed with various chemicals, and thereafter the mixture is concentrated by a condenser, such as an evaporator, immediately before coating. In the former method, it is difficult to provide a uniform mixture when various chemicals are added after the emulsion has been produced, whereby the quality of the product might be increased. In the latter method, some problems occur, such as a pressure loss when the condensed emulsion is fed to a coating device, difficulty in removing generated bubbles, and difficulty in washing the coating device. Also, in both methods the condensed emulsion results in a decreased quantity of coating per unit area of the web, which results in the necessity of applying the coating in a thin layer, and it is difficult to provide a uniform coating due to the higher viscosity of the coating liquids.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a method and apparatus for achieving high speed coating by decreasing the drying load without producing inferior product quality or coating problems. This object may be realized by coating a photographic emulsion on a web and thereafter concentrating the coating by means of microwave energy without cooling and setting the coating.
It has generally been known in the drying of photographic light-sensitive material that the best results are obtained, in terms of product quality, by slow wind drying over a long period of time at a low temperature, but this method is obviously not very efficient. As a result of further studies, it has been found that the quality of photographic light-sensitive material is most heavily influenced during the period from the later stage of a constant drying rate period to a falling (or decreasing) drying rate period, while the material quality is less influenced during the other drying periods. Thus, if the material is slowly dried by wind at a low temperature only from the later stage of the constant drying rate period to the falling drying rate period, the material quality will not be greatly affected even if the material is dried as quickly as possible in other periods.
The present invention utilizes such knowledge, whereby the photographic emulsion is coated on the web and thereafter irradiated by microwave energy to quickly dry and concentrate it during the early and middle periods in the constant drying rate period, after which the coating is cooled and set, and drying from the later stage of the constant drying rate period to the falling drying rate period takes place slowly at a low temperature without greatly affecting the quality of the dried material. Drying by means of microwave irradiation can be performed more efficiently and in less time than drying by means of wind, and therefore even if the drying starting at the later stage of the constant drying rate period is performed slowly at a low temperature by means of air blowing, the overall drying period can still be shortened. While the ratio of time required between the constant drying rate period and the falling drying rate period depends upon the kind, composition or the like of the photographic emulsion to be coated, it is normally 1 to 2, and accordingly, the drying time may be considerably shortened by the present invention.
When a solidified film is formed at the surface of the coating during the course of drying, it impedes the movement of water out of the coating and impairs the drying progress. With microwave irradiation, however, the interior of the coating is first heated so that the coating may be dried and concentrated without the formation of a film on the surface of the coating, and hence there is no hinderance to the subsequent normal drying by wind after the coating has been concentrated.
The irradiation of microwave energy onto the surface of the coating may be performed after coating without cooling and setting the coating. Spraying gases are preferably employed in addition to the microwave irradiation. When a boundary layer of high humidity is formed in the neighbourhood of the surface of the coating due to the water content vaporized from the interior and surface of the coating, it becomes a barrier to subsequent vaporization of the water content. The wind removes the boundary layer, and fresh air being fed into the concentrating device assists in maintaining constant humidity and drying conditions therein and in preventing the condensation of moisture.
The gases used for such purposes are not particularly limited as long as they are inactive relative to the coating and involve no handling dangers, and inactive gases such as nitrogen, carbon dioxide, helium or the like may be used in addition to air. From the economical viewpoint, air is most preferable in achieving the above-described purposes.
The temperature and humidity of the gas depends upon the kind, composition and the like of the photographic emulsion to be used, but the temperature is normally 5° to 35° C., and preferably 15° to 25° C., and the humidity is normally less than 50%RH, and preferably less than 30%RH.
As for the airflow, the greater the better within the limit of producing no unevenness in the coating surface. The actual value thereof varies with an extent of the fluidization of the coating by the microwave irradiation, that is, with the microwave intensity. Normally, a suitable airflow will be less than 10 m 3 /m 2 min, preferably about 1 to 5 m 3 /m 2 min.
The term microwave in the present invention refers to a.c. frequencies above several MHz but below ten thousand MHz. Because of industry Standards the most commercially available oscillators at present have usable frequencies of either 915 MHz or 2,450 MHz.
The concentration by microwave irradiation terminates at a point whereat the later stage of the constant drying rate period begins. It is difficult to express such point by the percentage of water because it varies with the kind and composition of emulsion, but it is generally the point where the percentage of water in the coating based on the average transfer weight is approximately 200%. That is, it is desirable that any water content above about 200% by removed by the microwave irradiation, with the percentage of water given by: ##EQU1##
In the present invention the water content in the coating is normally concentrated by the microwave irradiation immediately after coating, and thereafter, the coating is cooled and set. The cooling and setting are performed in a conventional manner. That is, they are normally performed by low temperature air at a dry bulb temperature of from -10 to 10° C.
After being cooled and set the coating is dried by blowing air at a dry bulb temperature of from 15° to 45° C. and relative humidity 10- 50%RH against the coating with an airflow of 10 to 40 m 3 /m 2 min.
The thus dried coating is then humidity controlled by air at a bulb dry temperature of from 20° to 40° C. and a relative humidity of from 50 to 70%RH.
The steps of cooling and setting the coating are not always required. For example, cooling and setting can be omitted where the coating fluidity has been decreased to an extent that the surface of the coating is not disordered by the application of air thereto.
Generally speaking, the greatest equipment cost for making photographic light-sensitive material involves the air conditioning installation. Since the cost of such installation is generally in proportion to the airflow used, it is thus very important to minimize the airflow requirements in order to reduce the final cost of the photographic light-sensitive material. Further, the amount of airflow largely occupies in the operational cost, so that the minimization of the amount of airflow greatly contributes to reduce the operational cost. The airflow required for the microwave irradiation is smaller than that required for a conventional drying process only by air, and the drying time as a whole is shortened, whereby it is possible to materially reduce the airflow and the costs of the installation and operation.
The photographic emulsion to be coated sometimes contains methanol, ethanol and other organic solvents in the amount of about 2 to 15 wt%, and it is known that these solvents are normally vaporized during the first half of the drying process. In the present invention, however, these solvents are almost completely vaporized during the microwave concentration stage. Since the quantity of air used in the concentration stage is generally small, the density of the vaporized organic solvents contained in waste gases from the concentrating device is thus quite high, and it is therefore possible to readily recover such organic solvents as a source of public hazard.
The photographic light-sensitive material produced effectively by the method of the present invention includes a layer of silver halide emulsion on a support, and the emulsion may include silver chloride, silver bromide, silver iodide, silver chloride bromide, silver iodide bromide, and silver chloride iodide bromide.
The protective colloid for the emulsion includes gelatin, which is most common, and water soluble high polymer compounds such as gelatin derivatives, such as phthalic gelatin, colloidal albumin, polyvinyl alcohol, etc., independently or jointly.
The weight ratio of the protective colloid to silver halide can be varied widely. Fog may effectively be prevented when the weight ratio of silver halide to protective colloid is in excess of 0.8.
The silver halide photographic emulsion may be chemically sensitized by a method well-known in the air with a compound containing a labile sulfur atom such as sodium thiosulfate, alkylthiocarbazide, etc., a compound such as the gold (I) thiocyanate complex salt, a reducing agent such as stannous chloride, polyalkyleneoxide derivative or a combination of these. Further, the silver halide photographic emulsion may be optically sensitized only by the cyanine dye such as 1,1'-diethylcyanine iodide, 1,1'-diethyl-9-methylcarbocyanine bromide, anhydro-5,5'-diphenyl-9-ethyl-3,3'-di(2-sulfoethyl)-benzoxazolocarbocyanine hydroxide and the like and a combination of these. In addition, the emulsion may include chemicals which can release development restraining substances, such as 2-iodo-5-pentadecylhydroquinone, 2-methyl-5-(1-phenyl-5-tetrazolylthio)-hydroquinone, or the like, stabilizers such as 4-hydroxy-6-methyl-1,3,3a,7-tetrazaindene, benzimidazole, 1-phenyl-5-mercaptotetrazole, hardeners such as formaldehyde, mucobromic acid, and coating assistants such as saponin, sodium alkylbenzenesulfonates.
The emulsion maybe coated in layers on supports such as polyester, polycarbonate, polystyrene, cellulose acetate, polypropylene and the like.
The protective colloid layer including gelatin may be placed on the emulsion layer. In this case, the content of the protective colloid is 3 to 10 wt% of the coating liquid for the protective layer. The protective layer may also be coated simultaneously with the emulsion layer.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 shows a simplified flow diagram of an apparatus for making photographic light-sensitive material according to one embodiment of the present invention;
FIG. 2 shows a perspective view of one embodiment of a microwave irradiating and concentrating device; and
FIG. 3 shows a schematic sectional view of one embodiment of a microwave concentrating device in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A continuously travelling web 1, after having a photographic emulsion applied by a coating device 2, is fed into a microwave concentrating device 3 comprising a microwave oscillator 4 and an undulating waveguide 5. The coated web passes through the waveguide via slits 7 while being supported on transport rollers 6, and is subjected to irradiation by microwave energy to concentrate the coating. Reference numeral 8 designates a dummy load for absorbing microwave energy not absorbed by the coating, and exhaust ports 9 are provided for discharging gases. The slits 7 should be of sufficient size enough to allow the web to pass therethrough without contacting the waveguide 5, while at the same time being small enough to minimize microwave leakage. To meet such conflicting requirements it is desirable to provide eaves (not shown) at the upper and lower portions of the slits 7 having surfaces parallel to the travelling direction of the web. The length of the eaves in such direction is normally 1 to 2 times of width of the slits. The actual size of the slit gaps depends not only on the presence of the eaves but also on the microwave frequencies used. Generally speaking, with eaves installed the gap size is 25 to 40 mm, preferably about 30 mm, for 915 MHz, and 10 to 20 mm, preferably about 15 mm, for 2450 MHz.
Air is supplied to the microwave concentrating device 3 in a direction of arrow A and is subjected to temperature and humidity adjustment by dehumidifiers 10, heaters 11 and coolers 12. The air is then blown onto the web and enters the waveguide 5, and is discharged outside the system by fans 13 through the exhaust ports 9. The discharged air is recycled to recover the solvent by means of a solvent recovering unit 14 and reused along with newly supplied air.
The web 1 with the coating concentrated in the manner described is fed into a cooling and solidifying device 15 where a low temperature air flow is applied to cool and solidify the coating. This low temperature air is also recycled.
The web with the cooled and solidified coating is then fed to a drier device 16 where the web is dried by air in a conventional manner, and thereafter it is fed to a humidity control zone (not shown). The air used in the drier 16 is recycled and reused.
The present invention provides the following advantages:
(1) The drying time may be considerably reduced.
(2) The drying zone can be made shorter if the coating speed is kept constant, and therefore the cost of the installation may be reduced.
(3) In an existing drying device an increase in production may be realized by increasing the coating speed without lengthening the drying zone.
(4) The drying of the web in the zone which most greatly affects the material quality is carefully carried out by air, and hence the overall drying time may be considerably reduced without greatly affecting quality.
(5) Organic solvents contained in the photographic emulsion may easily be recovered to reduce environmental protection costs.
(6) Since the interior of the coating is heated by microwave irradiation, a blocking film caused by drying the surface of the coating is not formed on the surface of the coating as in the case of wind drying.
(7) Since the coating is concentrated before being cooled and set, the time required for cooling and solidifying is reduced. It is also possible to omit the solidifying process depending upon the kind and composition of photographic emulsion used. Therefore, the cost of the solidifying installation and the overall operational cost can be reduced.
For a better understanding of the effects of the present invention, the following examples are given:
EXAMPLE 1
A photographic emulsion as a lower layer with components consisting of silver bromide (50 mg/100 cm 2 ) and gelatin (40 mg/100 cm 2 ), and an upper protective coating layer including gelatin (9 mg/100 cm 2 ), mat agent and surface active agent were coated in quantities of 90 cc/m 2 and 20 cc/m 2 , respectively, in layer relation, on a polyethylene terephthalate film.
After coating a specimen A was passed through a cooling air zone at a dew point of -10° C. and a dry bulb temperature of 3 to 5° C. for fifteen seconds similar to the prior art to cool and solidify the film surface, after which it was dried in 6.3 minutes by air at a dry bulb temperature of 20° to 35° C. and a relative humidity of 30 to 65%, and humidity controlled by air at a dry bulb temperature of 25° C. and a relative humidity of 60% for one minute.
A specimen B was cooled and solidified under the same conditions as specimen A and then dried for five minutes using air at a dry bulb temperature of 25° to 38° C. and a relative humidity of 30 to 65%, after which it was humidity controlled under the same conditions as specimen A.
A specimen C was heated for 20 seconds employing the method according to the present invention as shown in FIGS. 1 to 3, using two microwave oscillators of 2,450 MHz and 5 kW to vaporize approximately one half of the water content, after which it was cooled for ten seconds at a dry bulb temperature of 5° to 8° C. to cool and solidify the film surface. The specimen was then dried for 4.6 minutes using air at a dry bulb temperature of 25° C. and a relative humidity of 40 to 65%, and further humidity controlled under the same conditions as specimen A.
The thus obtained specimens A, B and C were cut into two pieces 5 cm square, left in a relative humidity atmosphere of 90% for one minute, and thereafter placed one on the other under a load of 1 Kg and left in an atmosphere of 45° C. for two days. The respective specimens were then removed and the areas at which they adhered were measured to obtain the results given in Table 1 below.
TABLE 1______________________________________Specimen A 15%Specimen B 55%Specimen C 18%______________________________________
As seen from Table 1, specimens A and C were good. With respect to photographic properties, physical properties of coating layer and other performance criteria, there was no appreciable difference between the respective specimens. Specimen C according to the present invention thus exhitited equal performance despite the fact that its drying zone was on the order of 70% shorter, including the microwave heating zone, than in the case of specimen A.
EXAMPLE 2
A photographic emulsion as a lower layer consisting of silver bromide (90 mg/100 cm 2 ) and gelatin (40 mg/100 cm 2 ), and an upper protective coating layer including gelatin (18 mg/100 cm 2 ), mat agent and surface active agent were coated in quantities of 98 cc/m 2 and 18 cc/m 2 , respectively, in layer relation, on a polyethylene terephthalate film 80 μ thick and 30 cm wide continuously travelling at 20 m/min.
The coatings were cooled, solidified and dried in a manner similar to Example 1 to obtain specimens D, E and F.
The thus obtained specimens were subjected to development and fixation treatment without being allowed to dry, and their degrees of haze were measured to obtain the results given in Table 2 below.
TABLE 2______________________________________Specimen D 35%Specimen E 52%Specimen F 34%______________________________________
As seen from Table 2, specimen F according to the present invention exhibited performance equal to that of the specimen D despite its higher drying speed. With respect to other performance criteria, there was practically no difference.
EXAMPLE 3
A positive collar photographic emulsion as a lower layer consisting of silver bromide (40 mg/100 cm 2 ), gelatin (21 mg/100 cm 2 ) and a coupler, and an upper protective coating layer including gelatin (10 mg/100 cm 2 ), mat agent and surface active agent were coated in quantities of 60 cc/m 2 and 20 cc/m 2 , respectively, in layer relation, on a cellulose triacetate film 135 μ thick and 30 cm wide continuously travelling at 20 m/min.
After coating, a specimen G was cooled and solidified in an air cooling zone at a dry bulb temperature of 2° C. for 25 seconds and further air dried at a dry bulb temperature of 25 to 40 C. and a relative humidity of 30 to 50% for 4.8 minutes, after which it was himidity controlled at 25° C. and 60% R.H.
A specimen H was processed in accordance with the present invention. That is, the temperature of the coated surface was measured in a non-contact manner by an infrared meter and air at a dew point of -2° C. and a dry bulb temperature of 27° C. was fed over the surface for 2.0 minutes while the output power of the microwave oscillators was adjusted such that the temperature of the coated surface was maintained at 20° to 25° C. The specimen was then further dried at 25°- 30° C. and 30- 40% R.H., after which it was humidity controlled under the same conditions as specimen G.
After testing specimens G and H as to the photographic properties (such as fog and sensitivity) and physical properties (such as scratch strength and the amount of swelling) of their coating surfaces, no significant differences were found between them even though specimen H was dried at a speed approximately 40% higher than specimen G. | A photographic emulsion coating on a travelling web 1 is irradiated by microwave energy propogated through a slotted, undulating waveguide 5 to condense or concentrate the coating by evaporating a significant percentage of its water content, thereby shortening the overall drying time for a given coating rate. A forced flow of air and/or other gases is established through apertures 9 in the waveguide under controlled temperature and humidity conditions, and the internal heating effected by the microwaves prevents the formation of a surface film which might impede subsequent drying. | 5 |
This is a continuation of Ser. No. 10/463,959, filed on Jun. 18, 2003, now abandoned, which claims the benefit of U.S. Provisional Application No. 60/438,361, filed Jan. 7, 2003
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process for concurrently fractionating and hydrotreating a full range naphtha stream. More particularly a selected boiling range naphtha stream is subjected to simultaneous hydrodesulfurization and splitting into a light boiling range naphtha and a heavy boiling range naphtha and thereafter polishing the light fraction or the recombined light and heavy fraction in a manner to prevent or reduce recombinant mercaptans.
2. Related Information
The composition of untreated naphtha as it comes from the crude still, or straight run naphtha, is primarily influenced by the crude source. Naphthas from paraffinic crude sources have more saturated straight chain or cyclic compounds. As a general rule most of the “sweet” (low sulfur) crudes and naphthas are paraffinic. The naphthenic crudes contain more unsaturates and cyclic and polycylic compounds. The higher sulfur content crudes tend to be naphthenic. Treatment of the different straight run naphthas may be slightly different depending upon their composition due to crude source.
Petroleum distillate streams contain a variety of organic chemical components. Generally the streams are defined by their boiling ranges which determine the compositions. The processing of the streams also affects the composition. For instance, products from either catalytic cracking or thermal cracking processes contain high concentrations of olefinic materials as well as saturated (alkanes) materials and polyunsaturated materials (diolefins). Additionally, these components may be any of the various isomers of the compounds.
Reformed naphtha or reformate generally requires no further treatment except perhaps distillation or solvent extraction for valuable aromatic product removal. Reformed naphthas have essentially no sulfur contaminants due to the severity of their pretreatment for the process and the process itself.
Cracked naphtha as it comes from the catalytic cracker has a relatively high octane number as a result of the olefinic and aromatic compounds contained therein. In some cases this fraction may contribute as much as half of the gasoline in the refinery pool together with a significant portion of the octane. Such cracked-steam sources such as from FCC, coker, visbreaker (and the like) typically contain around 90% of all of the “destination sulfur” that would have reported to refinery gasoline in the absence of all desulfurization treatment.
Catalytically cracked naphtha gasoline boiling range material currently forms a significant part (˜⅓) of the gasoline product pool in the United States and it provides the largest portion of the sulfur. The sulfur impurities require removal, usually by hydrotreating, in order to comply with product specifications or to ensure compliance with environmental regulations.
The most common method of removal of the sulfur compounds is by hydrodesulfurization (HDS) in which the petroleum distillate is passed over a solid particulate catalyst comprising a hydrogenation metal supported on an alumina base. Additionally copious quantities of hydrogen are included in the feed. The following equations illustrate the reactions in a typical HDS unit:
RSH+H 2 →RH+H 2 S (1)
RCl+H 2 →RH+HCl (2)
2RN+4H 2 →2RH+2NH 3 (3)
ROOH+2H 2 →RH+2H 2 O (4)
Typical operating conditions for naphtha HDS reactions are:
Temperature, ° F. 450-650 Pressure, psig 250-750 H 2 recycle rate, SCF/bbl 700-2000 Fresh H 2 makeup, SCF/bbl 150-500
After the hydrotreating is complete, the product may be fractionated or simply flashed to release the hydrogen sulfide and collect the now desulfurized naphtha.
In addition to supplying high octane blending components the cracked naphthas are often used as sources of olefins in other processes such as etherifications. The conditions of hydrotreating of the naphtha fraction to remove sulfur will also saturate some of the olefinic compounds in the fraction, thereby reducing the octane and causing a loss of source olefins.
Various proposals have been made for removing sulfur while retaining the more desirable olefins. Since the olefins in the cracked naphtha are mainly in the low boiling fraction of these naphthas and the sulfur containing impurities tend to be concentrated in the high boiling fraction the most common solution has been prefractionation prior to hydrotreating. The prefractionation produces a light boiling range naphtha which boils in the range of C 5 to about 250° F. and a heavy boiling range naphtha which boils in the range of from about 250-475° F.
The predominant light or lower boiling sulfur compounds are mercaptans (RSH)while the heavier or higher boiling compounds are thiophenes and other heterocyclic compounds. The separation by fractionation alone will not remove the mercaptans. However, in the past the mercaptans have been removed by oxidative processes involving caustic washing. A combination oxidative removal of the mercaptans followed by fractionation and hydrotreating of the heavier fraction is disclosed in U.S. Pat. No. 5,320,742. In the oxidative removal of the mercaptans the mercaptans are converted to the corresponding disulfides.
In addition to treating the lighter portion of the naphtha to remove the mercaptans, it has been traditional to use the light portion as feed to a catalytic reforming unit to increase the octane number if necessary. Also the lighter fraction may be subjected to further separation to remove the valuable C 5 olefins (amylenes) which are useful in preparing ethers.
U.S. Pat. No. 6,083,378 discloses a naphtha splitter as a distillation column reactor to treat a portion or all of the naphtha to remove the organic sulfur compounds contained therein. The catalyst is placed in the distillation column reactor such that the selected portion of the naphtha is contacted with the catalyst and treated. The catalyst may be placed in the rectification section to treat the lighter boiling range components only, in the stripping section to treat the heavier boiling range components only, or throughout the column to widely treat the naphtha. In addition the distillation column reactor may be combined with standard single pass fixed bed reactors or another distillation column reactor to fine tune the treatment.
In hydrodesulfurizations it is known that H 2 S can recombine to form mercaptans thus increasing the amount of sulfur in the product. In U.S. Pat. No. 6,416,658 a full boiling range naphtha stream is subjected to simultaneous hydrodesulfurization and splitting into a light boiling range naphtha and a heavy boiling range naphtha followed by a further hydrodesulfurization by contacting the light boiling range naphtha with hydrogen in countercurrent flow in a fixed bed of hydrodesulfurization catalyst to remove recombinant mercaptans which are formed by the reverse reaction of H 2 S with olefins in the naphtha during the initial hydrodesulfurization. In particular the entire recovered portion of the light naphtha from a reaction distillation column hydrodesulfurization is further contacted with hydrogen in countercurrent flow in a fixed bed of hydrodesulfurization catalyst.
However, it has been found that the lighter portion of the recovered light naphtha is virtually free of mercaptans and it is not necessary to further treat this fraction. It has been discovered that by fractionating the recovered light portion to remove a specific lighter portion of the light boiling range naphtha which is substantially free of mercaptans, the load on the countercurrent catalyst bed is reduced, therefore allowing a smaller catalyst bed, while still providing hydrodesulfurization treatment for that portion of the light boiling naphtha with the recombinant mercaptans.
It is an advantage of the present invention that the sulfur may be removed from the light and/or heavy naphtha portions of the stream without any substantial loss of olefins. Thus, reduced levels of sulfur may be obtained in the selected fraction and/or the entire stream with reduced costs.
SUMMARY OF THE INVENTION
Briefly the present invention is an improvement in a catalytic distillation hydrodesulfurization process comprising:
(a) feeding a naphtha boiling range hydrocarbon stream containing organic sulfur compounds and hydrogen to a distillation column reactor; (b) concurrently in said distillation column reactor
(i) separating said naphtha into a light boiling range naphtha and a heavy boiling range naphtha (ii) contacting said naphtha and hydrogen with a hydrodesulfurization catalyst to selectively react the organic sulfur compounds therein with said hydrogen to form H 2 S;
(c) recovering a portion of said light boiling range naphtha wherein said light boiling range naphtha contains recombinant mercaptans; (d) removing said heavier boiling range naphtha from said distillation column reactor, e.g. as bottoms; and (e) passing said portion of said light boiling range naphtha to a countercurrent flow reactor for contact with hydrogen in fixed bed hydrodesulfurization catalyst to reduce the recombinant mercaptans therein;
wherein the improvement comprises fractionating said portion of light boiling range naphtha to remove a lighter fraction thereof, said lighter fraction being substantially free of mercaptans, from said countercurrent flow reactor before contact of said lighter fraction with said fixed bed catalyst. The fixed catalyst bed may be conventional or alternatively in the form of a catalytic distillation structure.
Both the light naphtha fraction and the heavy naphtha fraction are preferably hydrodesulfurized in a catalytic distillation step. The H 2 S produced in the catalytic distillation is removed with the light naphtha fraction, and separated therefrom. Thus, it is in the light naphtha fraction that the recombinant mercaptans are most likely to form, because the H 2 S will be in contact with that fraction during its recovery.
In the counterflow operation the newly released H 2 S at a given location is unavailable to react again with olefins in the lower sections of the column to form another mercaptan. Hence, there is substantially no H 2 S arriving in the bottom of the column and therefore there is no equilibrium limitation on the mercaptan removal. Furthermore, since the lighter fraction which will exit with the H 2 S, contacts the H 2 S in the absence of a catalyst there is substantially no reverse reaction with the olefins in that fraction to form recombinant mercaptans.
The light gasoline that is removed from the countercurrent flow HDS unit without contacting the fixed bed of catalyst is represented as a fraction in the boiling range of initial point through endpoint equal to initial point ∓20° F. for the overheads from the reaction distillation column. This fraction is substantially mercaptan free. The entire fraction or a portion thereof may be removed to obtain a benefit as described. An advantage of the present invention is that the countercurrent flow reactor generally treats less, preferably less than about 55%, of the overheads from the catalytic distillation HDS, rather than 80-100% previously used. The present improvement allows the use of moderate pressures, preferably 100-270 psig, in the countercurrent flow HDS reactor to obtain temperatures sufficient for HDS and the use of less catalyst.
“Recombinant mercaptans” as that term is used herein means those mercaptans which are not in the feed to the present process but are the reaction products of the H 2 S generated by the hydrogenation of the present process and alkenes in the feed. Thus, the recombinant mercaptans are not necessarily the same as those destroyed by the hydrogenation of first portion of the present process, although they may be. The present catalytic distillation hydrogenation is considered to dissociate substantially all of the mercaptans in the feed and the small amounts of mercaptans observed in the product streams are in fact recombinant mercaptans. Although the catalytic distillation reaction is superior to the prior art straight hydrogenation for removing mercaptans, the dynamic system of a catalytic distillation allows sufficient time for some undesirable recombination reaction to occur. Thus, in the present invention the combination of a less efficient countercurrent, straight pass hydrodesulfurization is sufficient to dissociate the small quantities of recombinant mercaptans by having only a limited contact of the produced H 2 S before it is removed from the reaction zone.
As used herein the term “distillation column reactor” means a distillation column which also contains catalyst such that reaction and distillation are going on concurrently in the column. In a preferred embodiment the catalyst is prepared as a distillation structure and serves as both the catalyst and distillation structure. The term “reactive distillation” is used to describe the concurrent reaction and fractionation in a column. For the purposes of the present invention, the term “catalytic distillation” includes reactive distillation and any other process of concurrent reaction and fractional distillation in a column regardless of the designation applied thereto.
BRIEF DESCRIPTION OF THE DRAWING
The FIGURE is a schematic representation of one embodiment of the invention having catalyst beds in a distillation column/naphtha splitter which are used to treat both the light and heavy fraction to hydrogenate and remove mercaptans by reactive distillation in which the overhead light fraction is recovered and sent to a separate fixed bed countercurrent flow polishing reactor.
DETAILED DESCRIPTION OF THE INVENTION
The feed to the process comprises a sulfur-containing petroleum fraction which boils in the gasoline boiling range. Feeds of this type include light naphthas having a boiling range of about C 5 to 330° F. and full range naphthas having a boiling range of C 5 to 400° F. end point to as high as, e.g. 470° F. end point. Generally the process is useful on the naphtha boiling range material from catalytic cracker products because they contain the desired olefins and unwanted sulfur compounds. Straight run naphthas have very little olefinic material, and unless the crude source is “sour”, very little sulfur.
The sulfur content of the catalytically cracked fractions will depend upon the sulfur content of the feed to the cracker as well as the boiling range of the selected fraction used as feed to the process. Lighter fractions will have lower sulfur contents than higher boiling fractions. The front end of the naphtha contains most of the high octane olefins but relatively little of the sulfur. The sulfur components in the front end are mainly mercaptans and typical of those compounds are: methyl mercaptan (b.p. 43° F.), ethyl mercaptan (b.p. 99° F.), n-propyl mercaptan (b.p. 154° F.), iso-propyl mercaptan (b.p. 135-140° F.), iso-butyl mercaptan (b.p. 190° F.), tert-butyl mercaptan (b.p. 147° F.), n-butyl mercaptan (b.p. 208° F.), sec-butyl mercaptan (b.p. 203° F.), iso-amyl mercaptan (b.p. 250° F.), n-amyl mercaptan (b.p. 259° F.), α-methylbutyl mercaptan (b.p. 234° F.), α-ethylpropyl mercaptan (b.p. 293° F.), n-hexyl mercaptan (b.p. 304° F.), 2-mercapto hexane (b.p. 284° F.), and 3-mercapto hexane (b.p. 135° F.). Typical sulfur compounds found in the heavier boiling fraction include the heavier mercaptans, thiophenes, sulfides and disulfides.
The reaction of organic sulfur compounds in a refinery stream with hydrogen over a catalyst to form H 2 S is typically called hydrodesulfurization. Hydrotreating is a broader term which includes saturation of olefins and aromatics and the reaction of organic nitrogen compounds to form ammonia. However hydrodesulfurization is included and is sometimes simply referred to as hydrotreating.
Catalysts which are useful for the hydrodesulfurization reaction include Group VIII metals such as cobalt, nickel, palladium, alone or in combination with other metals such as molybdenum or tungsten on a suitable support which may be alumina, silica-alumina, titania-zirconia or the like. Normally the metals are provided as the oxides of the metals supported on extrudates or spheres and as such are not generally useful as distillation structures. However, in the countercurrent fixed-bed polishing reactor, such shapes are directly useful when loaded at optimal particle size which would be slightly larger than those typically encountered in conventional concurrent trickle bed reactor technology. Alternatively, catalyst may be packaged in a suitable catalytic distillation structure which characteristically can accommodate a wide range of typically manufactured fixed-bed catalyst sizes.
The catalysts contain components from Group V, VIB, VIII metals of the Periodic Table or mixtures thereof. The use of the distillation system reduces the deactivation and provides for longer runs than the fixed bed hydrogenation units of the prior art. The Group VIII metal provides increased overall average activity. Catalysts containing a Group VIB metal such as molybdenum and a Group VIII such as cobalt or nickel are preferred. Catalysts suitable for the hydrodesulfurization reaction include cobalt-molybdenum, nickel-molybdenum and nickel-tungsten. The metals are generally present as oxides supported on a neutral base such as alumina, silica-alumina or the like. The metals are reduced to the sulfide either in use or prior to use by exposure to sulfur compound containing streams and hydrogen.
The catalyst may also catalyze the hydrogenation of the olefins and polyolefins contained within the light cracked naphtha and to a lesser degree the isomerization of some of the mono-olefins. The hydrogenation, especially of the mono-olefins in the lighter fraction may not be desirable.
If at the temperature of use in the present process, the ratio of the partial pressures of H 2 S/(H 2 S+H 2 ) falls below a temperature-dependent critical value, then desulfiding of the catalyst is likely to occur. Desulfiding is not a harmless event, because the mixed catalysts are typically formulated to yield optimally formed metal clusters on the alumina substrate. Typically, one of the two metals will form base clusters on the alumina support, and the second metal will tend to decorate the first metal along the edges of those clusters. The process of desulfiding a catalyst and then subsequently resulfiding that catalyst is not an identically reversible process. Catalyst mishandled in this way will usually suffer noticeable activity loss and selectivity loss. By selectivity loss, is meant that more olefin loss and more octane-number loss will be registered at a given level of total-sulfur conversion after a desulfiding incident when compared with earlier performance. The desulfiding is most likely to occur in the lower portion of the catalyst bed that would be H 2 S deprived compared to other portions of the catalyst beds where H 2 S is produced by the decomposition of the mercaptans. The desulfiding of the catalyst may be reduced by introducing H 2 S into the catalytic distillation column and/or the polishing column, for example with the hydrogen feed in an amount sufficient to maintain the catalyst.
The catalytic distillation step is carried out at a temperature in the range of 400 to 800° F. at 50 to 400 psig pressure with hydrogen partial pressure in the range of 0.1 to 100 psi at 20 to 1200 scf/bbl at WHSV in the range of 0.1 to 10 hr −1 based on feed rate and particulate catalyst packaged in structures. If advanced specialty catalytic structures are used (where catalyst is one with the structure rather than a form of packaged pellets to be held in place by structure). The LHSV for such systems should be about in the same range as those of granular-based catalytic distillation catalyst systems as just referenced.
In the present countercurrent flow reaction the temperature is generally in the range of 400 to 550° F. at 90 to 280 psig pressure. The hydrogen partial pressure is generally in the range of 7 to 250 psi. The hydrogen is fed below the catalyst bed at 50 to 250 scf/bbl. The light naphtha is fed in such that the rate of bottoms draw to catalyst corresponds to a WHSV in the range of 3-15 hr −1 . The catalyst may be the same as that used in the catalytic distillation structure and it may be utilized in such a structure, although it is not necessary to do so. Generally catalytic particles are ⅛″-½″ dimension to facilitate favorable mass flow and favorable fluid-to-particle mass transfer characteristics.
Preferably there is a stripper section above the catalyst bed in the fixed bed countercurrent reactor. This provides for removal of additional dissolved H 2 S and the lighter fraction from the catalytic distillation column. For example, in order to reduce recombinant in a feed containing mercaptans 252 ppm H 2 S to 2-5 ppm in the effluent from the counterflow trickle bed reactor which is operated at 215 psig, 400° F., WHSV of 8 hr −1 , in a 7 foot bed of Co/Mo, ¼″ catalyst, a stripper zone of 6-12 theoretical stage is required above the catalyst bed. This arrangement reduces the light overheads contacting the fixed bed from about 25-40% and reduces the dissolved H 2 S in the reaction zone, e.g., 5-10 ppm, hence reducing the recombinant mercaptans to negligible levels.
The concentration of H 2 S necessary to avoid desulfiding the metals on the catalyst is quite small. So long as the required amount of H 2 S relative to flowing hydrogen is equaled or exceeded everywhere in the vapor exposed to the bed, the catalyst will not desulfide. Also, as temperature is increased, the amount of H 2 S relative to hydrogen present that is necessary to achieve this control will increase as well.
The properties of a typical hydrodesulfurization catalyst are shown in Table I below.
TABLE I
Manufacture
Criterion Catalyst Co.
Designation
C-448
Form
Tri-lobe Extrudate
Nominal size
1.2 mm diameter
Metal,
Wt. %
Cobalt
2-5%
Molybdenum
5-20%
Support
Alumina
The catalyst typically is in the form of extrudates having a diameter of ⅛, 1/16 or 1/32 inches and an LD of 1.5 to 10. The catalyst also may be in the form of spheres having the same diameters. They may be directly loaded into standard single pass fixed bed reactors which include supports and reactant distribution structures. However, in their regular form they form too compact a mass for operation in the catalytic distillation hydrodesulfurization tower and must then be prepared in the form of a catalytic distillation structure. (However, in the polishing reactor, extrudates are perfectly acceptable if the size range is in the ⅛, ¼, ⅜, ½ inch ranges. Typically particles used in countercurrent fixed bed operation are roughly twice the average diameter of those used in corresponding concurrent fixed bed reactors). The catalytic distillation structure must be able to function as catalyst and as mass transfer medium. The catalyst must be suitably supported and spaced within the column to act as a catalytic distillation structure. In a preferred embodiment the catalyst is contained in a structure as disclosed in U.S. Pat. No. 5,730,843, which is hereby incorporated by reference. More preferably the catalyst is contained in a plurality of wire mesh tubes closed at either end and laid across a sheet of wire mesh fabric such as demister wire. The sheet and tubes are then rolled into a bale for loading into the distillation column reactor. This embodiment is described in U.S. Pat. No. 5,431,890 which is hereby incorporated by reference. Other catalytic distillation structures useful for this purpose are disclosed in U.S. Pat. Nos. 4,731,229, 5,073,236, 5,431,890 and 5,266,546 which are also incorporated by reference.
Reaction conditions for sulfur removal only in a standard single pass fixed bed reactor are in the range of 500-700° F. at pressures of between 400-1000 psig. Residence times expressed as liquid hourly space velocity are generally typically between 1.0 and 10. The naphtha in the single pass fixed bed reaction may be in the liquid phase or gaseous phase depending on the temperature and pressure, with total pressure and hydrogen gas rate adjusted to attain hydrogen partial pressures in the 100-600 psia range. The operation of the single pass fixed bed hydrodesulfurization is otherwise well known in the art.
The conditions suitable for the desulfurization of naphtha in a distillation column reactor are very different from those in a standard trickle bed reactor, especially with regard to total pressure and hydrogen partial pressure. Typical conditions in a reaction distillation zone of a naphtha hydrodesulfurization distillation column reactor are:
Temperature
450-700°
F.
Total Pressure
75-300
psig
H 2 partial pressure
6-75
psia
WHSV of naphtha
about 1-5
H 2 rate
10-1000
scf/bbl
The operation of the distillation column reactor results in both a liquid and vapor phase within the distillation reaction zone. A considerable portion of the vapor is hydrogen while a portion is vaporous hydrocarbon from the petroleum fraction.
In the catalytic distillation it has been proposed that the mechanism that produces the effectiveness of the present process is the condensation of a portion of the vapors in the reaction system, which occludes sufficient hydrogen in the condensed liquid to obtain the requisite intimate contact between the hydrogen and the sulfur compounds in the presence of the catalyst to result in their hydrogenation. In particular, sulfur species concentrate in the liquid while the olefins and H 2 S concentrate in the vapor allowing for high conversion of the sulfur compounds with low conversion of the olefin species. The result of the operation of the process in the distillation column reactor is that lower hydrogen partial pressures (and thus lower total pressures) may be used.
As in any distillation there is a temperature gradient within the distillation column reactor. The temperature at the lower end of the column contains higher boiling material and thus is at a higher temperature than the upper end of the column. The lower boiling fraction, which contains more easily removable sulfur compounds, is subjected to lower temperatures at the top of the column which provides for greater selectivity, that is, no hydrocracking or less saturation of desirable olefinic compounds. The higher boiling portion is subjected to higher temperatures in the lower end of the distillation column reactor to crack open the sulfur containing ring compounds and hydrogenate the sulfur. The heat of reaction simply creates more boil up, but no increase in temperature at a given pressure. As a result, a great deal of control over the rate of reaction and distribution of products can be achieved by regulating the system pressure.
Operating conditions for the present fixed bed countercurrent flow naphtha HDS reactions may be:
Temperature, ° F.
400-550
Pressure, psig
140-275
H 2 recycle rate, SCF/bbl
70-200
Fresh H 2 makeup, SCF/bbl
25-75
In the polishing reactor or section of the present invention, the liquid is downflow and the hydrogen is upflow, thus the stripping action is also present and the very small amounts of recombinant mercaptans are readily reduced to even lower levels. As discussed above, the optimum conditions for the two types of reactions are not in the same range. Since the major hydrodesulfurization is going on in the reactive distillation, the activity of the countercurrent flow straight pass hydrodesulfurization is somewhat compromised, however it is adequate to achieve a sufficient removal of the recombinant mercaptans to meet the objectives of the treatment.
Referring now to the FIGURE the catalyst 12 a and 14 a is loaded into the stripping section 12 and the rectification section 14 of a naphtha splitter 10 configured as a distillation column reactor. The naphtha is fed into the distillation column reactor 10 between the sections via flow line 1 and hydrogen is fed below both sections via lines 2 and 2 a . The light naphtha (comprised of a light ends and a mid light) is boiled up into the rectification section 14 and removed along with unreacted hydrogen and H 2 S as overheads via flow line 3 . The light naphtha is condensed in condensers 20 and separated from the hydrogen and H 2 S and other lights in receiver/separator 30 via flow line 22 . The liquid (light naphtha) from the separator 20 and 30 is removed via flow line 5 and 5 a , respectively and a portion returned to the distillation column reactor as reflux via flow line 6 . Alternatively, the flow line 6 A may be utilized instead of 6 so that all of the liquid leaving the colder drum 30 is diverted to reactor 50 . The recovered liquid portion not returned as reflux is directed to the straight pass countercurrent flow reactor 50 , via line 21 , where it contacts the hydrogen in the hydrodesulfurization catalyst bed 15 . The hydrogen is fed via line 16 below the bed 15 . The hydrogen passes upward through the catalyst bed and the downflowing light naphtha where it contacts the recombinant mercaptans and covers a portion to H 2 S.
The light naphtha has a spread in the range between its End Point and the Initial Point of preferably about 120° F. or less the H 2 S, and the unreacted hydrogen exit the countercurrent flow reactor 50 to separator 60 . The unreacted hydrogen and H 2 S exit the separator 60 and pass via line 17 to the separator 20 for treatment with the overhead from the catalytic distillation reactor and the condensed and the condensed light ends are recovered from separator 60 via line 27 . A stripping section 24 above the catalyst bed 15 , but below the feed 21 to countercurrent polishing reactor 50 is used to keep H 2 S in the feed from flow line 21 away from the catalyst bed 15 . A rectification section 25 is provided above feed 21 to facilitate the H 2 S and light ends removal and to separate the liquids (the mid light) which may be entrained in the upflow gas stream. Mid light naphtha product is recovered via line 18 and heavy naphtha product is recovered via line 19 . The catalytic distillation column has a reboiler 40 and the fixed bed reactor 50 may have an optional reboiler 41 , which will result in some reflux into the catalyst bed. The upper section of reactor 50 is preferably a multistage contact zone where H 2 S dissolved in the incoming light naphtha can be stripped out so that dissolved H 2 S is not present in the catalyst zone 15 .
The preferred operating conditions and results for the distillation column reactor 10 of the FIGURE are as follows:
Pressure, psig
100-300
H 2 rate, scfh
150-1000
H 2 partial pres., psi
5-75
WHSV
0.2-10
% HDS
90-99
In the fixed bed reactor 50 of the FIGURE the preferred operating conditions and results are:
Pressure, psig
90-250
H 2 rate, scf
50-250
H 2 partial pres., psi
10-180
WHSV(based on bottom flow)
3-16
Mercaptans(combined w/stream 21), ppm
<2-10
Note that a small recycle compressor (not shown ) may be necessary in line 17 , if the countercurrent reactor 50 operates a lower pressure than column 10 .
The hydrogen may be recycled back to the reactors. Vents may be sufficient to maintain the H 2 S levels low enough for the reaction. However, if desired, the recycle gas may be scrubbed using conventional methods to remove the H 2 S. The light naphtha recovered in line 27 may be combined with the mid light of line 18 to replicate the overheads 3 from column 10 having reduced total sulfur. Similarly the entire naphtha feed to the process (line 1 ) may be recreated having reduce total sulfur by combining all three product streams from lines 27 , 18 and 19 . | A process for concurrently fractionating and hydrotreating a full range naphtha stream. The full boiling range naphtha stream is subjected to simultaneous hydrodesulfurization and splitting into a light boiling range naphtha and a heavy boiling range naphtha, which have been treated to convert mercaptans in the fractions to H 2 S, which is separated with and separated from the light naphtha which is further hydrodesulfurized by contacting the light boiling range naphtha with hydrogen in countercurrent flow in a fixed bed of hydrodesulfurization catalyst to remove recombinant mercaptans which are formed by the reverse reaction of H 2 S with olefins in the naphtha during the initial hydrodesulfurization wherein the improvement comprises fractionating said portion of light boiling range naphtha to remove a lighter fraction thereof from said countercurrent flow reactor before contact of said lighter fraction with said fixed bed catalyst, because the lighter fraction is substantially free of mercaptans and is not benefitted by further treatment. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a waveform equalizer for a Teletext signal and, more particularly, to an improvement in an operation timing control signal generator for use in this waveform equalizer.
Recently, in Europe, United States of America and Japan, Teletext services have been practiced, whereby textual and graphic information is inserted into television broadcast signals and this teletext signal is converted to a television signal in a TV receiver to be displayed on the screen. As shown in FIG. 1, the Teletext signal is inserted, in the form of a two-level signal and, subsequent to a color burst signal, into one or more horizontal scanning lines in the vertical blanking interval of the television signal. A data packet of the Teletext signal consists of a header and information data. According to the system in Japan, the data packet has 320 samples and the sampling clock rate is 5.73 mega samples/second.
Recently, picture ghost cancellers (waveform equalizer) have been put into practical use to remove ghost components (waveform distortion), which are caused due to multipath transmission, from a received television signal. Where the waveform distortion is caused in the television signal, due to the ghost components, it is also obviously caused in the Teletext signal.
In the case of picture ghost cancellers, the video signal has to be processed on a real-time basis to remove ghost components. For this purpose, the ghost canceller has to be designed so as to operate at high speed, which has lead them to be large in circuit scale and costly. It is economically disadvantageous to use such a picture ghost canceller to remove the ghost components from the Teletext signal having a frequency band narrower than the video signal. Further, since the above picture ghost cancellers cannot eliminate short-delay ghosts, they cannot be adapted for a Teletext signal equalizer without modification.
Since the Teletext signal is transmitted within the vertical blanking interval of the television signal, the real-time process is not always necessary to eliminate the waveform distortions. That is, the waveform equalizing process can be performed during a video signal interval (one field interval). This means that an equalizer which may be simple in arrangement and operate at low speed is enough for equalization of the waveform of the Teletext signal. An example of the waveform equalizer for the Teletext signal is disclosed in Japanese Laid-Open Patent Publication No. 56(1981)-166674.
In the Teletext waveform equalizer, various kinds of timing control signals are needed to determine the operation timings of circuits. Further, for the waveform equalizing process, about 90,000 shots of 5.73 MHz clock pulses are needed in one field interval (about 16 milliseconds). A low-speed microprocessor is not adapted for generating such high-speed timing signals. To generate such timing control signals, a conventional timing control signal generator mainly consists of TTL logic ICs including counters, flip-flops and the like. However, in this case, the number of elements constituting the counters increases, causing the circuit scale to be remarkably enlarged. Actually, about 300 general-purpose logic ICs are used.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an operation timing control signal generator for use in a Teletext waveform equalizer which is simple in construction and, therefore, is of low cost.
A timing control signal generator, according to the invention comprises a synchronous circuit means connected to receive a television signal for generating a field start signal indicative of the start of a vertical blanking interval and sample clock pulses which have a frequency equal to the sample clock rate of a Teletext signal and are phase-locked with samples of the Teletext signal; first and second counter means; and first and second read only memories (ROMs). A feature of the invention resides in storing in the ROMs information indicative of level changes of the timing control signals and level information of the timing control signals at the timings when the level changes occur. These ROMs are accessed by the first and second counters driven by the sample clock pulses. For reducing the capacity of the ROMs, according to another embodiment of the invention, the first ROM stores the respective level information of the timing control signals at respective level change timings of the timing control signals, while the second ROM stores information as to a time duration between each level change timing and the next level change timing of a predetermined timing control signal.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a waveform diagram of a television signal for explaining a Teletext signal;
FIG. 2 is a schematic block diagram of a conventional Teletext signal waveform equalizer;
FIG. 3 is a block diagram of an input waveform memory in FIG. 2;
FIG. 4 is a signal waveform diagram for explaining the operation of the input waveform memory in FIG. 3;
FIG. 5 is a block diagram of a timing control signal generator for a Teletext signal waveform equalizer according to one embodiment of the present invention;
FIG. 6 shows a partially modified form of the timing control signal generator of FIG. 5; and
FIG. 7 is a block diagram of a timing control signal generator according to another embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
For easy understanding of the present invention, the Teletext signal waveform equalizer (ghost canceller) disclosed in the foregoing patent publication will now be described in detail with reference to FIGS. 2 and 3. A television signal demodulated by a demodulator (not shown) is applied through an input terminal 11 to an analog-to-digital (A/D) converter 12 and a timing signal generating circuit 13. The television signal is converted to a 6-bit digital form by the A/D converter 12. A digital output signal of the A/D converter 12 is applied to an input waveform memory 14, which extracts a Teletext signal in response to the timing signal generator 13 and stores the waveform of the Teletext signal in a digital form. The A/D converter 12 may be constituted so as to convert only the Teletext signal to a digital signal. The A/D converter 12 converts each sample of the two-level Teletext signal to six-bit digital data including a sign bit. As will be easily understood, in the case where the Teletext signal is subjected to waveform distortions due to ghost components, the amplitude of each sample varies depending upon the magnitude of ghost components.
The Teletext signal waveform read out from the input waveform memory 14 is applied to a transversal filter 15 for waveform equalization. An output signal of the transversal filter 15 is sent to a utilization circuit (not shown) through an output terminal 16, and to a subtracter 17 and a reference waveform generator 18. The reference waveform generator 18 examines the sign of a digital output signal of the transversal filter 15 and applies an output signal to the subtracter 17. The output signal of the reference waveform generator 18 is +1 when the sign is plus and -1 when it is minus. The subtracter 17 calculates the difference between the output signals of the transversal filter 15 and reference waveform generator 18, thereby producing data indicative of an error in the waveform. The error waveform data is stored in an error waveform memory 19.
The error waveform data from the error waveform memory 19 and the Teletext signal waveform from the input waveform memory 14 are applied to a tap weight computing circuit 20, which computes the correlation between the input waveform and the error waveform to obtain optimum tap weights of the transversal filter 15. The tap weights are stored in a tap weight memory 21, thereby applying tap weight data to the transversal filter 15. In this example, the number of taps of the transversal filter 15 is 24.
In the Teletext signal waveform equalizer, the error waveform computation, tap weight computation and convolution computation in the transversal filter 15 may be performed within one field interval of the television signal. The operation of the Teletext signal waveform equalizer is governed by a clock signal CK (5.73 MHz in the case of the Teletext system in Japan) and various kinds of timing control signals from the timing signal generator 13.
The operation of the waveform equalizer will now be described. It is assumed that the input waveform memory 14 is comprised of a shift register with 324 stages each connected to receive a word of 6-bits in parallel as shown in FIG. 3. The shift register is divided into a 300-stage shift register 33 and a 24-stage shift register 35. A switching circuit 32 is connected between an input terminal 31 and the shift register 35, while a switching circuit 34 is connected between the shift registers 33 and 35. Each of the electronic-type switching circuits 32 and 34 is of a single-pole double-throw type having stationary contacts A and B. The contacts A and B of the switching circuit 32 are connected to the input terminal 31 and the output of shift register 35, respectively. The contacts A and B of the switching circuits 34 are connected to outputs of the shift registers 33 and 35, respectively. The electronic switching circuits 32 and 34 are controlled by the operation of timing control signals SW1 and SW2 respectively, which are generated from the timing signal generator 13. Clock signals CK1 and CK2 of 5.73 MHz from the timing signal generator 13 are supplied to the shift registers 33 and 35, respectively, so that digital data is shifted right in the shift registers 33 and 35. The number of stages of the shift register 35 is equal to the number of taps of the transversal filter 15.
The operation of the input waveform memory 14 is shown in Table 1 below.
TABLE 1______________________________________ NumberMode SW1 SW2 CK1 CK2 of times______________________________________Input A A ○ ○ 324EW1- ○1 B B X ○ 24 ○2 B A ○ ○ 1EW2- ○1 B B X ○ 24 ○2 B A ○ ○ 1..EW48- ○1 B B X ○ 24 ○2 B A ○ ○ 1Rear- B A ○ ○ 276rangement______________________________________
In this table, O denotes that the clock signal is supplied to the corresponding shift register and X means that no clock signal is supplied.
The timing signal generator 13 receives the TV signal to generate a field start signal FSTRT indicative of the start of a field, the sample clock signals CK, CK1 and CK2 phase-locked to the color burst signal, and various operation timing control signals including SW1 and SW2. The sample clock frequency (5.73 MHz) is set at 8/5 times the color burst signal frequency (3.58 MHz) of the NTSC color television system.
The operation of the input memory 14 in FIG. 3 will now be described with reference to FIG. 4 and Table 1. The timing signal generator 13 detects a vertical blanking interval of a TV signal to generate the field start signal FSTRT. The switching circuits 32 and 34 are switched to the side B by the timing control signals SW1 and SW2, respectively. This occurs from the start of the field until the beginning of the Teletext signal, which allows the shift registers 33 and 35 to be disconnected from the A/D converter 12. When a Teletext signal is received, the switching circuits 32 and 34 are switched to the side A by the timing control signals SW1 and SW2, respectively, thereby permitting the digital Teletext signal to be loaded into the shift registers 33 and 35. During this interval, 324 clock signals CK1 and CK2 are applied to the shift registers 33 and 35 respectively, so that 324 samples of the Teletext signal are loaded into the shift registers 33 and 35 with 324 stages. Six bits of each sample are loaded into the shift register in parallel. The above-mentioned mode is the input mode shown in Table 1.
After the Teletext signal has been loaded, the switching circuits 32 and 34 are changed over to the side B by the control signals SW1 and SW2 and thereafter an error waveform operation mode EW is started. The error waveform operation is executed 48 times for every 24 samples. In a first error waveform operation interval EW1- Å1 , the clock pulse CK1 is not generated but 24 clock pulses CK2 are generated. Thus, the data in the shift register 35 recirculates while being loaded into the transversal filter 15. Thereafter, in the interval EW1- Å2 , the switching circuit 34 is switched to the side A, for only one clock pulse interval, by the switch control signal SW2 while the switching circuit 32 remains switched to the side B. Therefore, the shift registers 33 and 35 serve as a circulating shift register for the interval EW1- Å2 so that the data is shifted one stage right. The convolution is computed in accordance with the 24 sample data loaded in the transversal filter 15 and the tap weight coefficients from the tap weight memory 26. The result of the computation is applied to the subtracter 17 to produce an error waveform component which is stored in the error waveform memory 19. In this way, the data is read out 48 times on a 24-sample data unit basis from the input waveform memory 14, so that the convolution computation is executed 48 times and the data necessary for the gain computation for 24 taps of the transversal filter 15 is stored in the error waveform memory 19.
Thereafter, the rearrangement mode is executed to rearrange data in the shift registers 33 and 35 in the original input sequence. In this mode, the switching circuit 32 is switched to the side B and the switching circuit 34 is switched to the side A. 276 clock pulses CK1 and CK2 are applied to the shift registers 33 and 35, respectively, and 324 sample data are rearranged in the original input sequence. Thereafter, the processes of tap-weight computing in the tap weight computing circuit 20, writing the computed tap weight into the tap gain memory 21, and correcting the tap weights of the transversal filter 15 are executed.
An embodiment of the timing control signal generator, according to the invention, which is arranged to generate the operation timing control signals such as SW1 and SW2 will now be described with reference to FIG. 5. A video signal is applied, through an input terminal 40, to a synchronous circuit 41 which detects a vertical sync signal and extracts a color burst signal. Thus, the synchronous circuit 41 produces the field start signal FSTRT and the sample clock signal CK of 5.73 MHz. The field start signal FSTRT is applied to clear terminals of first and second counters 42 and 48, thereby initializing these counters every field. The sample clock signal CK is applied to the A/D converter 12 through a terminal 46 and to clock terminals of the counter 42 and a latch circuit 50.
The counter 42 is a binary counter having bit outputs which is responsive to the rising edge of the sample clock signal CK to vary output state in accordance with the binary system. Outputs of the counter 42 are coupled to address inputs of a first read only memory (ROM) 43. Binary data indicative of the changing points, occuring after the start of the field, of the operation timing control signals such as SW1 and SW2 has been stored in the ROM 43. Data of 1 is stored in addresses of the ROM 43 which correspond to times at which the level of at least one of the timing control signals including SW1 and SW2 changes after the start of the field, while data of 0 is stored in other addresses thereof. The addresses of the ROM 43 are designated by the counter 42 for measuring time from the start of the field on the basis of the sample clock signal CK. Therefore, data of 1 is read out from the ROM 43 whenever times, at which the level of the timing control signal should vary (these times have been predetermined), elapse with reference to the start time of the field.
An output signal of the ROM 43 is latched in a flip-flop 44 responsive to an inverted sample clock signal from an inverter 45, thereby driving the second counter 48. The counter 48 is a binary counter like the first counter 43, which counts 1 data outputs of the ROM 43, i.e., changing points of the timing control signal, thereby accessing a second ROM 49. The ROM 49 has, for instance, eight outputs corresponding to the number of necessary timing control signals for one address. ROM 49 stores, in each address thereof (corresponding to one changing point of the timing control signals) designated by counter 48, the level information (1 or 0) of each timing control signal at each changing point of the timing control signals. Consequently, eight data representative of the levels of eight timing control signals are read out from the ROM 49 at every changing point of the timing control signals.
Eight output data of the ROM 49 are latched into the latch circuit 50 responsive to the sample clock signal CK. Timing control signals T1 to T8 are taken from output terminals 47a to 47h of the latch circuit 50. For example, the control signals SW1 and SW2 as shown in FIG. 4 are taken from the output terminals T1 and T2. From an AND gate 51 to which the sample clock signal CK is applied and which is enabled by an inverted timing control signal SW2, is taken the clock signal CK1 to be applied to the shift register 33 of FIG. 3.
As described above, according to the present invention, due to the provision of two low-cost ROMs, the timing control signals for the Teletext signal waveform equalizer, which have little regularity and must vary at a speed of 5.73 MHz, can be generated on a relatively small circuit scale. According to the teaching of the present invention, the timing control signal generator may be sufficiently constituted by 10 to 20 general-purpose ICs. The circuit of the present invention can be easily integrated. If the timing control signal generator is realized by one ROM, the ROM necessitates a capacity of 90,000×8=720,000 bits to produce eight timing control signals. According to the embodiment of the present invention, two ROMs are used; therefore, the second ROM 49 may have a capacity of about 200 bits (the number of changing points of the timing control signals within a predetermined interval) per output, and thus the whole ROM capacity may be 90,000×1+256×8=92,000 bits.
Another embodiment of the present invention will now be described with reference to FIG. 6. In this embodiment, an eight-bit low-speed ROM is used as the first ROM. The sample clock signal CK is applied to a three-bit binary counter 57 so that its frequency is divided by 8. The MSB output of the counter 57 is applied to the clock input of the first counter 42. Outputs of the first counter 42 designate addresses of the first ROM 43. The MSB output of the counter 57 is inverted by an inverter 54 and then applied to a clock input of a latch circuit 55. Thus, the latch circuit 55 latches output data of the ROM 43 at the falling edge of the MSB output of the counter 57. Then, a selector 56 sequentially selects one of eight outputs of the ROM 43 in response to three-bit outputs of the counter 57 and sends it to the flip flop 44 in FIG. 5. Thereafter, various timing control signals are produced in a similar manner as in the case of FIG. 5.
Still another embodiment of the present invention will now be described with reference to FIG. 7.
In FIG. 7, a synchronous circuit 61 receives a video signal through an input terminal 60 to produce the field start signal FSTRT and sample clock signal CK. The field start signal FSTRT is applied to clear terminals of first and second counters 62 and 63. The sample clock signal CK is applied to a clock terminal of the counter 62 through an AND gate 64. The AND gate 64 is enabled by the Q output of a flip-flop 65. As will be described later, the AND gate 64 is enabled by the flip-flop 65 when at least one of the timing control signals changes. Therefore, the counter 62 counts one shot of sample clock signal CK when the level of at least one of the timing control signals changes after the counter 62 has been cleared by the field start signal FSTRT.
Outputs of the counter 62 are coupled to address inputs of first and second ROMs 66 and 67. Similarly to the ROM 49 in FIG. 5, the ROM 66 stores in each address the level data of 8 timing control signals at each change point thereof. The data read out from the ROM 66 is latched in a latch circuit 68 responsive to the sample clock CK from the AND gate 64. The latch circuit 68 holds data read out from the ROM 66 at the previous change point until the next change occurs in the timing control signals. Eight timing control signals are generated from eight outputs 68a to 68h of the latch circuit 68 in a similar manner as the foregoing embodiment.
The ROM 67 stores data as to the respective time durations of the 1-level intervals and 0-level intervals of one timing control signal, in other words, data as to time duration between adjacent change points of this timing control signal. The counter 63 is cleared through an OR gate 69 by the field start signal FSTRT or the Q output of the flip-flop 65. The counter 63 counts the sample clock signal CK to measure time running from a changing point of the timing control signal indicated by the Q output of the flip-flop 65. The outputs of the ROM 67 and counter 63 are compared by a comparator 70. When both outputs coincide, the comparator 70 sends a 1 output to the D input of the flip-flop 65. The inverted signal of the sample clock CK is applied through an inverter 71 to the clock terminal of the flip-flop 65. As a result, the flip-flop 65 holds the 1 output of the comparator 70 at the falling edge of the sample clock CK. Thus, the AND gate 64 is enabled to cause the counter 62 to count one sample clock CK, and at the same time the counter 63 is cleared, thereby allowing the measurement of time to be restarted. In this way, the timing control signals, necessary for the waveform equalization, are generated.
In the embodiment of FIG. 7, capacities of ROMs may be smaller than those in the case of FIG. 5. The number of all change points of eight timing control signals is about 200, so that 256×8=2,048 bits are enough for the first ROM 66. If a time duration between change points of the timing control signal is expressed by eight bits, the second ROM 67 may have a capacity of 256×8=2,048 bits. Therefore, the whole capacity of ROMs is 4,096 bits. | A timing control signal generator used in a Teletext signal waveform equalizer to remove waveform distortions in a Teletext signal inserted into a horizontal scanning line for a vertical blanking interval of a television signal and arranged to generate timing control signals for controlling the operation of the waveform equalizer. The timing of each of the timing control signals, at which the level variation thereof occurs, is predetermined. To generate these timing control signals by a small scale circuit arrangement, a pair of counters and a pair of read only memories are used. The first counter is cleared by a field start signal and counts sample clock pulses synchronized with the Teletext signal. The first ROM stores information indicative of level changes of the timing control signals and is accessed by the first counter. The level change information read out from the first ROM is counted by the second counter. The second counter accesses the second ROM which stores level information of the timing control signals at the level change timing of at least one of the timing control signals. The level information of the timing control signals read out from the second ROM is held in a latch circuit, thereby producing the timing control signals. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims benefit under 35 U.S.C. §120 of priority from U.S. Provisional Patent Application No. 60/461,319 filed on 8 Apr. 2003, entitled, “A PORTABLE WIRELESS GATEWAY FOR REMOTE MEDICAL EXAMINATION,” the subject matter of which is hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to the field of remote medical examinations for subjects, particularly in a non-medical environment, such as the home or office or even within an “Internet Cafe”. Preferably, the present invention is operable by individuals who are not medically trained, such as by the subject himself or herself.
BACKGROUND OF THE INVENTION
Currently, a number of different types of devices are available for non-invasive monitoring of human subjects. For example, the heart function can be monitored in a subject through the use of electrodes, which must be attached to the skin of the subject. Although non-invasive, such equipment is nevertheless uncomfortable for the subject, who is attached to a network of cables and wired sensors. In addition, such equipment is very expensive, limiting its use to hospitals and other medical settings in which both the cost and the discomfort of the subject can be justified. Furthermore, discomfort and the overwhelming technological appearance of current monitoring systems may result in the subjects becoming anxious when examined by medical personnel, thereby significantly altering the normal readings for these subjects.
However, there are many different situations in which non-invasive monitoring of a human subject is desired. For example, such monitoring could be very useful as part of the overall health maintenance of the human subject, and could be used in order to detect any type of deterioration in the physiological condition of the subject before a concomitant deterioration in the health of the subject becomes noticeable. Examples of adverse physiological conditions which could be detected with regular non-invasive monitoring include, but are not limited to, excessive weight gain or weigh loss; arrhythmia and other heart conditions; incipient diabetes in the form of improper glucose metabolism; and the loss of lung capacity or other problems with respiration.
Heart rate and blood pressure are important factors in determining the state of a person's health and the physical condition of a person's body in response to physical or emotional stress. Periodic monitoring of these physical parameters is particularly important for individuals having cardiac disease and/or lowered cardiac functioning, or high blood pressure. However, physically healthy individuals may also wish to periodically monitor their heart rate and blood pressure in stressful situations, for example when engaging in strenuous exercise or in work.
In order to support regular monitoring of human subjects in their normal environment, such as in the home and at the office for example, the equipment must be non-invasive and easy to use. The equipment would then be able to monitor at least one physiological parameter of the user, without requiring the user to perform any complicated actions and/or to operate complex devices. Indeed, it would be highly preferred for the equipment to be incorporated as part of the regular daily living routine of the subject, since the requirement for any additional or special actions on the part of human subject is likely to result in decreased compliance. In addition, the equipment should be robust yet inexpensive.
For ease of use, monitoring equipment carried by the user may be used. Such monitoring equipment is required to be ready for receiving an impromptu call initiated by a medical center. However, keeping the monitoring equipment active and ready to receive a call results in reducing the lifetime of its battery. Therefore there is a need for a system that enables the Medical Service Center to make an impromptu call to the monitoring equipment, while the monitoring equipment is not active (i.e., in a sleeping mode) without losing the information that is transferred from the Medical Service Center to the monitoring equipment.
Furthermore, preferably the subject should be able to transmit the collected medical information and to communicate verbally with medical personnel. Also, medical personnel should be able to view the subject and the data being collected. In order to make the remote medical service available to wide variety of users the communication with medical personal may be carried over a common communication link such as regular telephone lines.
Common remote medical examination systems may include at least one piece of monitoring equipment carried by the user. The monitoring equipment communicates over a wireless communication channel with a gateway. On the other side, the gateway communicates to a computer at a central service center using common communication protocols such as Internet Protocol (IP) over common telephone line, ISDN etc. Such a remote medical examination system is disclosed in PCT applications PCT/IL02/00994 or in PCT/IL02/00995, the contents of which are incorporated herein by reference. The advantage of such a system is that the user may move freely and do the normal activities that he or she is used to do while the system may monitor the subject's physical conditions. However, these systems are stationary and require some installation procedure and needs. Therefore the user may enjoy the system only while staying in the site where the system is installed, for instance in the subject's home or office.
In addition each user may have some personal data, such as: user's medical file history, special measuring programs, escalation procedures etc. It can be beneficial for a user if this information may be portable with the user and valid in case that the user is far from the site in which the remote system is installed. For example, in case that the user is in hospital, the medical personal there may have access to the system as well as to the personal medical files.
Therefore there is a need for a portable system and a method for medical monitoring system that may communicate with a medical service center. Such a system will spread the opportunity of a user to benefit from his medical services in variety of locations such as home, work, hotels hospitals etc. In addition, there is a need for a system in which personal medical data may be carried by the user.
Throughout this description the term “computer” includes, but is not limited to, Personal Computer (PC), laptop, notebook, palm computer, cellular phone etc. Henceforth, the description of the present invention may use the term ‘PC’ as a representative term for any of the above group or similar type system.
SUMMARY OF THE INVENTION
The present invention overcomes the deficiencies of the current art by providing a wireless portable gateway that may be connected to a common connector of a PC such as Universal Serial Bus (USB) connector. On the other hand, the wireless portable gateway may communicate with at least one portable measuring equipment device by using RF communication. The RF communication may be based on standards protocols such as Bluetooth or IEEE 802.11 (wireless LAN) or on a similar or proprietary protocol.
Such a portable gateway may have the shape of a USB flash memory disk with an internal or external antenna. The product is easily carried and installed by the user using the USB plug and play capabilities.
Other embodiments of the present invention may use other types of connectors/protocols rather than the USB. For example, other embodiments may use FIREWIRE or RS232 etc. Henceforth, the description of the present invention may use the term ‘USB’ as a representative term for any of the above group. Furthermore, the present invention is not limited to the shape of a USB flash memory disk and other shapes may also be used. Those embodiments may be connected directly to the PC connector or via a cable or a docking station. The embodiments may use the power coming from the PC connector or from external source or battery.
The PC may communicate with the medical center over any network solution such, as but not limited to, an Internet Protocol based network such as the Internet, Intranet, LAN etc. over communication links such as a telephone line, cellular, ISDN, ADSL etc. The PC may be used as an interface node on the communication link or may also be used as the monitor and the controller of the medical examination system, at the user site. In parallel to medical examination activities the PC may perform its common tasks.
The portable wireless gateway (PWG) may have a nonvolatile memory, such as but not limited to flash memory, EEPROM, RAM, etc. In an embodiment of the present invention the nonvolatile memory may contain the operating software that runs over the PC that is used as a host PC for communicating and controlling the medical measuring system at the user's current location. Such an embodiment may have two stages during its installation. At the first stage the PWG emulates a nonvolatile memory device, such as but not limited to a USB flash memory disk. After plugging the PWG to the USB plug, the user may use it as a USB flash memory disk and loads the operating software with or without a driver to the PC or the operating software may download and initialize itself automatically into the host PC computer. Then during the second stage, the medical measuring system is activated, using the operating software that was loaded to the host computer.
In other embodiments, the nonvolatile memory may include, in addition to the operating software or instead of the operating software, personal data such as, but not limited to, personal information, medical history, medical properties, statistical data of previous measurements, data regarding the physical condition of the user, special sensitivities of the user to medicines etc. In some embodiments, part or all of the personal data may be encrypted.
Other embodiments may use external media to store the operating software. For example, an exemplary embodiment may use CD ROM to store the operating software at the user's location. In such an embodiment, the operating software is loaded first into the PC from the CD ROM and then the PWG is plugged to the PC's connector. Or in some cases, upon plugging the PWG, the PC senses that a new hardware device is plugged in and requests the user to install the operating software of the new device from the CD ROM. In other embodiment of the present invention the operating software of the medical measuring system may be downloaded via the Internet.
In some embodiments of the present invention the PWG may include authentication and/or encryption capabilities. In some embodiments, the user may configure the PC to avoid storing medical information over its local disc. Instead or simultaneously any medical information may be stored in the PWG.
In other embodiments of the present invention, the nonvolatile memory may include an authentication code for authenticating the user to the service center. Such authentication may be protected using an encryption protocol.
In some embodiments of the present invention the PC may have audiovisual capabilities enabling the user to communicate with the call center.
In some embodiments of the present invention, the PWG may also communicate with other standard wireless domestic sensors, such as smoke detectors and burglary alarms, thus the PWG may receive their transmission and activate the operation software on the PC to alert the user, for example, by sending him an SMS massage to his cellular phone or by alerting the call center using its computer network capabilities.
Thus it is evident that the present invention, by utilizing a portable wireless gateway (PWG) that can be connected to any PC (an item which is present in many houses, offices, hospitals etc.). The PC is preferably connected to the Internet, enables the owner of the PWG to enjoy the medical measuring services in a plurality of locations.
It should be noted that the terms “home”, “remote”, “user's site”, “user's location” and “office” are used interchangeably herein and are used as examples only, in order to indicate the use of the present invention outside of a professional medical environment, and are not intended to be limiting in any way.
It should be noted that the terms “subject”, “user” and “patient” are used interchangeably herein. And that the terms “Medical Service Center”, “Call Center” and “Medical Center” are used interchangeably herein.
Hereinafter, the terms “microprocessor”, “computational device” and “computer” includes, but is not limited to, a general-purpose microprocessor, a DSP, a micro-controller or a special ASIC, hardware, a combination of hardware and software and/or firmware, designed for that purpose.
The method of the present invention could be described as a process for being performed by a data processor, and as such could optionally be implemented as software, hardware or firmware, or a combination thereof. For the present invention, a software application could be written in substantially any suitable programming language, which could easily be selected by one of ordinary skill in the art. The programming language chosen should be compatible with the computational device (computer hardware and operating system) according to which the software application is executed. Examples of suitable programming languages include, but are not limited to, Visual Basic, Assembler, Visual C, standard C, C++ and Java.
Other objects, features, and advantages of the present invention will become apparent upon reading the following detailed description of the embodiments with the accompanying drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
FIG. 1 is a schematic block diagram of a system according to an exemplary embodiment of the present invention;
FIG. 2 is a schematic block diagram of the PWG part of the system according to an exemplary embodiment of the present invention;
FIG. 3 is an exemplary flow diagram illustrating the installation of the PWG of FIG. 2 ; and
FIG. 4 is an exemplary flow diagram illustrating the removal of the PWG.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
Referring now to the drawings, in which like numerals refer to like parts throughout the several views, exemplary embodiments of the present invention are described.
The present invention is of a portable system and method for enabling medical data collection to be performed remotely, at the user location, while the user may easily carry the system, install and operate it in different locations. In each of these locations, there is a PC, which may be connected to a communication network that may access the central server, such as the Internet. In some locations in which the PC has audio/visual capabilities, the system may also permit Audio/Video conferencing between the subject and the medical personnel. Where the PC is not connected on-line to the network, it may store the medical data and forward it to the central server when the link becomes on-line, alternately it may store the data within its local disk or on the nonvolatile memory permanently or temporarily to be retrieved later by the user or by a medical personnel.
More specifically, the present invention is of an apparatus, which features bi-directional communication for transferring medical data with medical personnel operated Call Center, alternately or simultaneously, to a central server. The communication may be carried over any communication network such as the Internet via regular telephone line, ISDN, ADSL, CABLE TV, Cellular or any other type of physical network. The PC in which the apparatus is connected may be integrated with audio and video conferencing between a remote (home, “Internet Cafe” and office) subject and a medical service center. The invention is particularly useful for subjects having some type of medical risk who wishes to be supervised by a medical service center from numerous locations as long there is a PC with a USB connector or similarly functional connector and a network connection available.
According to an embodiment of the present invention, the system of the present invention features a remote apparatus and a medical service center with central server, which operates to enable remote monitoring for a subject at the home or other locations. The medical examinations may include visual and verbal communication and examinations with a two-way audio and video channel for enabling conversation between the subject and medical personnel at a medical service center.
FIG. 1 illustrates a schematic block diagram of a system according to an exemplary embodiment of the present invention. As shown, a system 100 features a wearable device 101 to be worn by a user, or a wireless medical device for measuring at least one physiological parameter of the user. Wearable device 101 may be as a wrist-mounted device, for example by being attached with a wristband or other fastening article to the wrist of the user; however, it should be understood that the device can be attached to clothing, carried in a pocket or attached to other parts of the body as well. The present invention enables such a measurement to preferably be transformed into medical information about the user. Such information may be sent through a portable wireless gateway 210 via USB connection, or similarly functional connection, 212 to PC 220 . PC 220 may or may not process the received information and transfers the data over the computer network 180 to central server 187 . The information may also be delivered to medical personnel (for example at a call center 185 ). The call center 185 and the central server 187 may be in the same site and may be connected over a LAN or INTERNET.
As previously noted, the present invention is not limited to wearable device. Other measuring equipment 190 a to 190 c may be used such as, but not limited to, scale, EGC, blood pressure measuring device, glucometer, smoke detectors, etc. Portable wireless gateway 210 may communicate with one or more measuring equipment devices 190 a to 190 c . Computer network 180 may be any network solution such as, but not limited to, Internet Protocol based network as the Internet, Intranet, LAN etc. over communication links such as telephone line, cellular, ISDN, ADSL etc. Henceforth, the description of the present invention may use the term ‘Internet’ as a representative term for any of the computer network solutions.
Examples of medical information which may be extracted from the measured physiological parameter or parameters include, but are not limited to: heart rate; heart rate regularity; breathing rate; arrhythmia of the heart (if any), as well as the general rhythm and functioning of the heart; blood pressure (systolic and diastolic); presence of abnormal body movements such as convulsions for example; body position; fall detection; general body movements; body temperature; presence and level of sweat; oxygen saturation in the blood; and glucose levels in the blood.
The PWG 210 may communicate with the wearable device 101 of the present invention through a wireless communication channel. The wireless communication may be based on common standards such as, but not limited to, Bluetooth, wireless LAN (IEEE 802.11) or proprietary protocol. Other embodiments may use IR communication instead of RF communication between the wearable device 101 and the PWG 210 . The PWG may convert the information coming from the wearable device into the format that fit the communication over USB.
PWG 210 is described in detail herein below in conjunction with FIGS. 2 , 3 and 4 . Additional information about the operation of wearable device 101 , call center 185 and the central server 187 is disclosed in PCT applications PCT/IL01/01187; PCT/IL02/00285; PCT/IL02/00995; PCT/IL02/00994 the contents of which are incorporated herein by reference.
In an exemplary embodiment of the present invention, the PWG, the wearable device or the medical device may also measure other parameters that may affect the subject's physical condition, including but not limited to, ambient temperature and humidity, lighting conditions, smoke and/or other material in the air, user location, distance from home etc.
The present invention may feature a manually/automatically activated medical measurement signal that may be initiated by the subject himself, by PC 220 , or from the call center 185 . The activate signal from the call center is transferred over the Internet 180 through PC 220 for being transmitted through the PWG 210 . In same cases the activate signal may be used as alarm signal in order to indicate an emergency or otherwise dangerous situation for the user. The activate/alarm signal may optionally be transmitted in the reverse direction according to a manual action of the user, such as pressing a “panic button” 116 for example.
Most preferably, the alarm signal is transmitted automatically upon measurement of the one or more physiological parameters of the user, preferably even if the user is unable to press the panic button. Optionally, the alarm signal may be given to the user, additionally or alternatively, for example by sounding an audible alarm, more preferably from the wrist-mounted device itself. Upon receipt of manually/automatically activated medical measurement of the user, the PWG may store it on its local nonvolatile memory module 240 or transfer it the host PC 220 to be stored there on its local hard disk or to be transferred further on to the central server 187 to be stored and analyzed. PC 220 , after receiving and processing the message may return the processed information to the PWG 210 in order to store in the nonvolatile memory of the PWG 210 .
Upon receipt of the manually/automatically activated alarm signal via PWG 210 , the PC 220 would preferably initiate immediately a call to a human operated call center 185 . Then the PC 220 may instruct, via PWG 210 , the user to manually activate the wearable device 101 to collect one or more current physiological measurements of the user. These measurements may be sent directly to PWG 210 , or alternatively may be analyzed, in the wearable device, in order to compute the medical parameters of the user before sending the results to PC 220 via the PWG 210 . The PC 220 may analyze the measurement. The human operator, at the medical center, would then preferably be able to assess the user's medical condition from the received information.
The wearable device 101 of the present invention may also monitor, at least periodically but more preferably continuously, the value or condition of one or more physiological parameters of the user. Continuous monitoring would more easily enable the device to transmit the alarm signal if measurements of one or more physiological parameters are collected and analyzed by a microprocessor to form medical information, which then could be determined to be above predefined criteria, such as unstable heart rate, or very high or low blood pressure, for example.
According to a non-limiting exemplary embodiment of the present invention, the wrist-mounted device 101 features one or more sensors attached to a wristband or other fastening article. The sensor(s) are preferably connected to a microprocessor, optionally by a wire but alternatively through a wireless connection. The microprocessor may optionally also be located within the wristband, or otherwise attached to the wristband. The sensor(s) preferably support automatic collection of at least one physiological measurement; more preferably, the microprocessor is able to execute one or more instructions for extracting clinically useful information about the user from such measurement(s).
The microprocessor more preferably operates a software program to process and analyze the data, which is collected, in order to deliver medical information. The measurement data, is then preferably transferred via PWG 210 to PC 220 . The PC 220 may relay such information to a central server 187 , which may be able to provide such information to medical personnel, for example as part of a call center 185 . Therefore, continuous monitoring of the physiological parameters of the user may optionally and more preferably be made, enabling better medical care for the user.
A general, non-limiting example of suitable methods for measuring the heart rate and/or other heart-related physiological parameters of a subject who is wearing the device according to the present invention may be found in the article “Cuff-less Continuous Monitoring of Beat-To-Beat Blood Pressure Using Sensor Fusion”, by Boo-Ho Yang, Yi Zhang and H. Harry Asada, submitted to IEEE transactions on Biomedical Engineering, 2000, hereby incorporated by reference as if fully set forth herein, where systolic and diastolic blood pressure are calculated using the pulse pressure shape per heartbeat. The disclosure does not describe a device, which has the functionality according to the present invention, but the disclosed method is generally useful for determining blood pressure from an external measurement of pressure from the pulse through the skin of the subject.
Device 101 may have at least one physiological sensor 102 for measuring at least one physiological parameter of the user, a vibration sensor 123 , preferably a piezoceramic sensor, which is not in direct contact with the skin of the user. Sensor 123 measures the movement of the wrist. The output of sensor 123 can be used by a processing unit 103 to capture the movement of the wrist and to recover some noise received by sensor 102 , which is caused by such movement.
Sensor 123 may be used for measuring the breath of the subject. For measuring the breath, the subject may be requested to put the hand (with the wearable device 101 ) over the subject's abdomen. In this position sensor 123 measures the movement of the abdomen, which is due to the subject's breath.
Device 101 may include additional ambient sensors 130 such as but not limited to a humidity sensor for measuring the ambient humidity. An exemplary humidity sensor may be the Humidity Gauge manufactured by Honeywell.
In order to support processing of the measured physiological parameter or parameters, processing unit 103 may optionally include internal RAM and non-volatile program memory (not shown). Also processing unit 103 may optionally include an extended data memory 105 located externally to processing unit 103 . Processing unit 103 preferably executes at least one instruction for processing the data obtained by sensor 102 .
Examples of such processing units 103 include but are not limited to PIC18LC452 by Microchip Technology Inc., which contains 10 channels of 10 bit A/D converters, a 1.5K bytes of internal RAM and 32K Bytes of non-volatile program memory.
Extended memory component 105 is preferably an electrically erasable non-volatile external memory component. Examples of such a memory component include but are not limited to FM24CL64-S (Ramtron, USA), with 64 Kbit of fast access read/write serial memory for storing temporary data related to the sampled physiological parameter.
Device 101 may have a real time clock 117 in order to provide an accurate time and date for each measurement, as device 101 can optionally store a few measurements before transmitting such data and/or information to PWG 210 , as described in greater detail below. Real time clock may also optionally be used for such applications as reminding the subject to take medication, perform a prescheduled measurement, and so forth. An A/D converter 109 with multiple inputs may be utilized if sensor 102 is an analog sensor, in order to convert the analog signal to a digital signal.
Device 101 may include a display unit or units 118 and/or 124 . The display unit may be used for displaying messages coming from the Call Center 185 , alarm information, instructions to the user etc.
Device 101 may also optionally feature a watchdog 115 , which monitors the function of device 101 . If the end of a watchdog time period is reached, device 101 is assumed to have a fault in its operation, and a master reset is preferably initiated automatically.
Device 101 preferably features an internal communication unit 104 , for at least unidirectional, but more preferably bi-directional, communication with PWG 210 . Communication unit 104 may act as an interface module between processing unit 103 and the communication protocol that is used over the wireless connection 121 with PWG 210 . In addition communication unit 104 may include the transmitter and the receiver that are used for the wireless communication 121 . Communication 121 may be RF communication based on standard protocols such as Bluetooth or IEEE 802.11 (wireless LAN) or on a proprietary protocol or other wireless communication methods such as IR. In case of using an RF proprietary protocol, the communication may be in any allocated frequency band but most preferably is in the unlicensed frequency spectrum.
In order to save power and increase the life of the battery, wearable device 101 may be placed into a sleep mode for the majority of the time. The wearable device 101 can be awaked according to a prescheduled program that is sent from the medical center or by manual activation.
FIG. 2 illustrates a schematic block diagram of the PWG part of the system 200 according to an exemplary embodiment of the present invention. The PWG section 200 of the system may comprise a PWG 210 and a PC 220 connected to the computer network 180 . PC 220 may have Audio/Visual capabilities. PWG 210 together with PC 220 act as the interface between the user and/or the wearable device 101 ( FIG. 1 ) and the central server 187 and/or the call center 185 . PC 220 may act as a host platform having a USB host controller for controlling and managing all USB transfers on the USB bus.
PWG 210 may be implemented as a single unit that is plugged into the USB port of PC 220 . PWG 210 may have the shape of a USB flash memory disk that is illustrated in U.S. design Pat. No. D 462,689 or D 468,090 the contents of which are incorporated herein by reference. However the present invention is not limited to this shape, other embodiments of the present invention may have other shapes or may be connected to other ports of PC 220 .
PWG 210 may comprise a USB module 230 , a non-volatile memory module such as flash memory, EEPROM, FRAM that may be logically divided into several non-volatile memory modules that are represented by three modules 240 a to 240 c , RF module 270 , antenna 245 , a memory 250 , authentication/encryption module 280 , and a processor/controller 260 that controls the operation of the different modules of PWG 210 . PWG 210 may comprise two buses, a data bus 266 and a control bus 263 or any other serial or parallel bus structure. In other embodiments of the present invention the two logical buses data bus 266 and a control bus 263 may share the same physical bus.
PWG 210 collects medical data from at least one monitor equipment such as wearable device 101 ( FIG. 1 ) via wireless communication. The data is sent to computer 220 over USB connection 212 and from PC 220 over the computer network 180 to the call center and/or the central server 187 .
USB module 230 acts as the interface module between the controller 260 of PWG 210 and PC 220 . USB module 230 may include the physical interface for receiving and transmitting electrical signals to and from PC 220 according to the communication protocol and a logical interface for decoding the address, synchronizing the signals and communicating with the controller 260 . The incoming packets from PC 220 are parsed and transferred to controller 260 over the internal buses 266 and/or 263 . In the other direction information from the controller 260 are received by USB module 230 , packetized according to the USB protocol and sent over the USB 212 port to the PC 220 . In case of using other type of communication port than USB, such as RS232, then USB module 230 may be replaced by an appropriate module.
Nonvolatile memory Module (NVMM) 240 a - 204 c may be divided into several logical non-volatile memory modules. NVMM 240 a may store the software that controls the operation of controller 260 . NVMM 240 b may store the operating software that is used by PC 220 for controlling the operation of the user site. This software may be loaded into PC 220 immediately after connecting the PWG 210 to the USB port 212 . NVMM 240 c may be used for storing the personal information of the user. The personal information may include authentication data of the user as well as medical information, such as the file history of the user, current results of medical measurements, the schedule for taking medicine, sensitivity information about medicines, or any type of data that may help a medical personal that take care of the user. The present invention is not limited to 3 modules of NVMM 240 a to 240 c and any other number of modules may be used. The operation of NVMM 240 is controlled by processor 260 . Exemplary NVMM may be built of nonvolatile memory, such as but not limited to flash memory, EEPROM, FRAM, a section of NVMM 240 may be built of non-erasable memory modules such as EPROM, PROM, etc.
RF module 270 is used as the complementary communication unit to the communication unit 104 ( FIG. 1 ) of the wearable device. RF module 270 may comprise an interface unit (not shown) that converts the data coming from the internal bus 266 and/or 263 according to the RF communication protocol and vice versa. The interface unit is connected in one side to bus 266 and/or 263 and on the other end to RF transmitter/receiver (not shown). The RF transmitter/receiver is connected to an antenna 245 that may be an external antenna or an internal antenna. RF module 270 and communication unit 104 may use a standard RF protocol, such as Bluetooth or IEEE 802.11 (wireless LAN) or any other technology or proprietary protocol. The RF frequency may be 433 MHz, 868 MHz, 915 MHz or any other frequency that may be used for such an application.
Other exemplary embodiments of the present invention may use wireless communication techniques other than RF, for example IR communication. In such an embodiment, the RF module will be replaced by an appropriate module having the appropriate transmitter/receiver and may have a lens/sensor instead of antenna 245 .
Memory module 250 may be a combination of any type of short-term memory such as RAM, SRAM and DRAM etc. with long-term memory such as EPROM that is used to support the operation of the controller 260 . The memory 250 may be used for storing the bootstrap program of controller 260 , the current program, setting parameters for monitoring equipment 101 and may be used for intermediate buffer for data coming from/to the Medical Center 185 to/from the Monitoring equipments 101 .
Controller 260 may be a computational device such as, but not limited to, a general-purpose microprocessor, a DSP, a micro-controller or a special ASIC designed for that purpose. In some embodiments of the present invention Controller 260 is used to control the operation of the internal modules of PWG 210 , while PC 220 is used to control the operation of system 200 as well as the wearable device 101 ( FIG. 1 ). In those embodiments, PC 220 may analyze the medical information that is coming from the wearable device 101 via PWG 210 .
In other embodiments of the present invention the PC 220 is just used as an interface between PWG 210 and the Internet 180 . In those embodiments the controller 260 may process the physiological measurements into medical information before transferring the results to the call center 185 via PC 220 and the Internet. In other embodiments of the present invention, processing the information may be done in the central server 187 ( FIG. 1 ).
An exemplary embodiment of the present invention may comprise an authentication/encryption module 280 . Authentication/encryption module 280 may be used in order to protect the privacy of the information that is stored in PWG 210 .
PC 220 and/or the PWG 210 may be used as an intermediate buffer that stores commands and/or data, which requested by the user using the software running on the PC 220 or commands and/or data coming from the Medical Service center 185 (FIG. 1 ) to the monitoring equipment 101 , until receiving a request from the monitoring equipment 101 to set communication with the PWG 210 . The information coming from the Medical Center 185 and/or from the user may include data like, but not limited to, type of measurements that are needed, setting the sleeping period, setting the internal clock of the monitoring equipment etc. Upon setting the communication between the two, the monitoring equipment 101 asks the PWG 210 to retrieve the information that has been received from the medical center 185 and/or from the user during the recent sleeping period. In this method of operation, the PWG 210 and/or PC 220 is used as an intermediate buffer for calls coming from both sides either from the monitoring equipment 101 or from the medical center 185 . The PWG 210 and/or PC 220 eliminate the need for the medical center as well as the monitoring equipment 101 to be on-line on the same time.
FIG. 3 is an exemplary flow diagram illustrating the operation of PC 220 and PWG 210 during the set up, after installing the PWG 210 in a USB port 212 ( FIG. 2 ). Upon installing 310 PWG 210 in the USB socket, a standard USB configuration process 315 takes place. In this process PC 220 configures the USB new device 210 and the mode of communication with USB device 210 . Although there are many different methods for configuring USB devices, for the purposes of clarity only and without intending to be limiting, the present invention is explained in greater detail below with regard to a method in which PC 220 issues commands and requests to a USB device through one endpoint. PC 220 queries USB device 210 through the other endpoint for status changes, and receives related packets if any such packets are waiting to be received.
Then in step 320 PC 220 may check whether the driver for the new device exist in its library. If yes, PC 220 moves to step 335 and starts loading the software that performs the operation of PC 220 . If not, PC 210 indicates to the user 325 about the new device and waits 330 for the loading of the driver of the PWG 210 by the user. The loading may be done from a portable media such as CD ROM or from the NVMM 240 b of device 210 or through the Internet. In case of using the PWG 210 as the storage media of the driver, the PWG 210 upon installing and turn on, emulates a USB flash memory disk device, which is known to PC 220 . Then the user may load 330 the driver from PWG 210 and continue to step 335 .
After loading 335 , PC 220 reads 340 the file history and the personal information of the user from NVMM 240 c updates PWG 210 accordingly and synchronizes with PWG 210 . Then PC 220 prompts the user to identify him and perform an authentication protocol. If 350 the authentication is successful, the PC 210 continues to step 355 and calls the call center 185 , updates it with the current situation of the user and the current communication link to the system 200 via PC 220 . If the authentication fails 350 , PC 220 returns to step 340 . This procedure may repeat for several times until the PC 220 sends a fail indication to the user.
Then PC 220 and PWG 210 may wait 360 for new call. The new call may come from the wearable device 101 ( FIG. 1 ) or from the call center 185 . The response of PGW 210 with PC 220 to incoming calls may be like the response of the remote gateway that is disclosed in the incorporated PCT applications (PCT/IL01/01187; PCT/IL02/00285; PCT/IL02/00995; PCT/IL02/00994) the contents of which are incorporated herein by reference.
FIG. 4 is an exemplary flow diagram illustrating the removal of the PWG 210 from the USB port 212 . When the user desires to remove the PWG 210 from the PC 220 , the user instructs PC 220 to disconnect 410 the PWG 210 . Then PC 220 updates 415 the call center 185 ( FIG. 1 ) and the central server 187 ( FIG. 1 ) about the disconnection and exchange the required information before the disconnection. Then 420 PWG 210 is updated regarding the incoming disconnection. PC 220 updates NVMM 240 c ( FIG. 2 ) with the current information. If during this period of time there is a valid connection with the wearable device 101 , the PWG 210 may update the wearable device too. Otherwise, the wearable device will be updated upon the next installation of PWG 210 .
After the updating, PC 220 may indicate 430 to the user that the PWG 210 may be safety removed. And the task of PC 220 is terminated 440 .
In the description and claims of the present application, each of the verbs, “comprise” “include” and “have”, and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of members, components, elements or parts of the subject or subjects of the verb.
In this application the words “unit” and “module” are used interchangeably. Anything designated as a unit or module may be a stand-alone unit or a specialized module. A unit or a module may be modular or have modular aspects allowing it to be easily removed and replaced with another similar unit or module. Each unit or module may be any one of, or any combination of, software, hardware, and/or firmware.
The present invention has been described using detailed descriptions of embodiments thereof that are provided by way of example and are not intended to limit the scope of the invention. The described embodiments comprise different features, not all of which are required in all embodiments of the invention. Some embodiments of the present invention utilize only some of the features or possible combinations of the features. Variations of embodiments of the present invention that are described and embodiments of the present invention comprising different combinations of features noted in the described embodiments will occur to persons of the art. The scope of the invention is limited only by the following claims. | A remote monitoring system that includes a portable measuring device that can be coupled to a portable wireless gateway. The portable measuring device obtains measurements including physiological data, movement data and ambient measurements and provides these measurements to the portable wireless gateway. The portable wireless gateway can interface with a networked personal computer through an USB connector. Once interfaced to the computer, the measurement data can be loaded into the computer and delivered to a central system through the networked personal computer. The system enables the monitoring of a user's medical information to allow diagnostics of the user. | 0 |
FIELD
[0001] The present invention relates to bioflavonoid impregnated cellulosic fibrous materials, processes for impregnating the materials and their uses. In particular, the invention relates to bioflavonoid impregnated cellulosic fibrous materials such as paper, paper towels, bamboo fibre and cardboard and articles formed from such materials.
BACKGROUND
[0002] Cellulosic fibrous materials such as paper are used in a wide variety of applications, ranging from domestic use to commercial use in, for example, hospitals, schools, kitchens and laboratories in the form of, for example, paper towels or face masks or even garments such as bamboo fibre socks.
[0003] Some materials would benefit from having antimicrobial properties. These include for example, cardboard, paper, cleaning wipes, paper towels or face masks or even garments.
[0004] GB2468836 discloses compositions comprising bioflavonoid compounds and their antibacterial, antifungal and antiviral activity but no suggestion was made that they could be used in impregnating fibres and materials.
SUMMARY OF THE INVENTION
[0005] The present invention relates to cellulosic materials impregnated with a bioflavonoid composition.
[0006] According to a first aspect of the invention there is provided a material impregnated with a bioflavonoid composition, the bioflavonoid content of the composition comprising at least naringin and neohesperidin.
[0007] Especially preferred is when the major part of the bioflavonoid content of the composition comprises naringin and neohesperidin. Preferably, naringin and neohesperidin together form at least 50% wt/wt, more preferably at least 70% wt/wt, for example at least 75% wt/wt, for example 75%-80% wt/wt of the bioflavonoid content of the composition (excluding other biomass).
[0008] The bioflavonoid content of the composition may further comprise one or more compounds of Formula (I):
[0000]
[0009] wherein R 1 is a hydroxyl or methoxyl and R 2 is hydrogen, hydroxyl or methoxyl and X is hydrogen or a saccharide.
[0010] A preferred option is when R 2 is hydrogen and R 1 is in the 3- or 4-position. Another option is when R 1 is 3-hydroxy and R 2 is 4-methoxyl. Preferably, X is H. More preferably, X is a saccharide.
[0011] In preferred embodiments, X is a disaccharide. Suitable disaccharides include combinations of two monosaccharides, preferably pyranoses, linked by a glycosidic bond, for example rhamnose and glucose, for example L-rhamnose and D-glucose.
[0012] Suitable disaccharides can have the structure:
[0000]
[0000] wherein one of R 3 and R 4 is H and the other OH or both are H or both are OH. Preferably R 3 is H and R 4 is OH so that the disaccharide is rutinose.
[0013] Favoured aglycones of bioflavonoids for use in this invention are the disaccharides 6-O-(alpha-L-rhamnopyranosyl)-beta-D-glucopyranose, also known as rutinose, and 2-O-(alpha-L-rhamnopyra-nosyl)-beta-D-glucopyra-rose.
[0014] Suitable compounds of Formula (I) include neoeriocitrin, isonaringin, hesperidin, neodiosmin, naringenin, poncirin and rhiofolin, in addition to naringin and neohesperidin. One of these compounds may be present in addition to naringin and neohesperidin, although a mixture of two or more of these compounds is particularly preferred.
[0015] Such mixtures can be obtained by extraction from bitter oranges and the end product is called citrus aurantium amara extract. Particularly preferred are the mixtures of bioflavonoid obtained from the extract of crushed whole immature bitter oranges. The mixtures can also be derived from the starting material comprised of the pith of immature, bitter (blood/red) oranges such as Seville oranges that are classed as ‘inedible’ and from which the pips, flesh and oily skin have been substantially removed or remain undeveloped.
[0016] Suitable mixtures can include 2, 3, 4, 5, 6, 7, 8, 9 or more compounds of Formula (I). A mixture comprising 2, 3, 4, 5, 6, 7, 8, or 9 of the above named bioflavonoids is preferable, for example containing 3, or containing 4, or containing 5, or containing 6, or containing 7, or containing 8, or containing 9 of said bioflavonoids.
[0017] It is presently believed that mixtures of such bioflavonoids have advantages over the use of a single bioflavonoid. It is particularly advantageous that extract of bitter oranges is employed without the need for isolating individual bioflavonoids. In an extract from bitter oranges biomass may be associated with up to 40-60% wt/wt, preferably about 55% wt/wt based on the weight of the bioflavonoid content of the composition. The biomass comprises pectins and other sugar derived materials. If it is desired to avoid biomass, other solubilising agents such as dextrines, for example cyclodextrin, may be employed if desired.
[0018] A particular advantage of many compositions described herein is that they may employ compounds of natural origin. Thus, for example, it is preferred to employ compounds of Formula (I) from bitter oranges. However synthetically or semi-synthetically obtained compounds may be employed if desired instead of the ones directly extracted from natural sources although this tends to be less favourable in view of cost.
[0019] The compositions may further comprise oleuropein. Preferably this is obtained from extraction from the leaf of the olive, for example Olea europaea . Such extracts typically contain 5% to 80% wt/wt, more preferably 10% to 70%, for example 20% wt/wt of oleuropein.
[0020] The wt/wt ratio of bioflavonoids to oleuropein can be 5:1 to 1:4, preferably 2:1 to 1:2, more preferably 1:2 to 1:1 and even more preferably 3:2. In addition to the bioflavonoid content of the composition, the composition may further comprise one or more fruit acids, for example citric acid, malic acid, and ascorbic acid. One or more of the acids are preferably neutralized with a suitable base, such as a quaternary ammonium base, for example a choline base, such as choline carbonate, bicarbonate or, preferably, hydroxide. More preferably, citric, malic and ascorbic acids are all used in the preparation of the composition, and especially preferred is when these are fully neutralized to provide citrate, malate and/or ascorbate salts. Especially preferred is choline ascorbate.
[0021] It has been found that the composition described herein is particularly effective in the presence of one or more organic acids. In one embodiment, the composition further comprises one or more organic acids.
[0022] A surprisingly effective organic acid is salicylic acid or its pharmaceutically acceptable salt optionally together with a further organic acid or pharmaceutically acceptable salt.
[0023] The salicylic acid may be obtained from willow bark extract. Alternatively, methods for synthesising salicylic acid are known to those skilled in the art.
[0024] Sometimes it is preferred that the salicylic acid is in the form of the acid rather than its salt.
[0025] Similarly, a further organic acid if present is similarly in the form of the acid rather than its salt. Suitable further organic acids include acids of up to 8 carbon atoms which are monobasic (i.e. one CO 2 H group), di-basic or tri-basic acid which optionally contain 1, 2 or 3 hydroxyl groups. Such further organic acid may be one or more of citric acid, malic acid, latic acid, tartaric acid, fumaric acid and the like.
[0026] Such compositions can provide an approximately neutral or acid pH, when used, for example from 3 to 8, more aptly 3.5 to 7, for example 4 to 5.
[0027] At present it is preferred to employ salicylic acid and citric acid in the compositions.
[0028] Such compositions may include a solubilising agent, for example, salicylic acid such as a dextrin such as cyclodextrin.
[0029] The compositions described herein have an extremely favourable safety and environmental profile. As well as showing extremely effective antimicrobial activity, the compositions are also non-toxic, non-corrosive, renewable and completely biodegradable. The compositions disclosed in WO 2012/017186 (herein incorporated by reference) are the preferred compositions of the present invention.
[0030] The cellulosic fibrous materials of the invention may be composed of paper or cardboard or bamboo fibres. Paper is defined as a material produced from a cellulose pulp which may be derived from wood, rags or grasses. The paper may be in the form of a paper towel, towelette, cloth, wipe or pad. Paper towels have a variety of applications, for example, paper towels are used to dry a person's hands after washing, also known as hand towels. Paper towels or wipes are also used for cleaning purposes to wipe down surfaces in a hospital, laboratory or a kitchen, for example, and can also be known as kitchen roll, kitchen paper or kitchen wipes. Pads are cellulosic fibre sponges and have application in personal hygiene and in medical kits. Wipes are produced as air-laid paper where the fibres are carried and formed to the structure of paper by air.
[0031] The paper may be treated with softeners, lotions or added perfume to create a desirable “feel” or texture.
[0032] Bamboo materials may be formed of bamboo fibre which is a cellulose fibre extracted or fabricated from natural bamboo. Bamboo is a sustainable crop and, as a natural product derived entirely from plant cellulose, bamboo fibre is biodegradable by microorganisms in soil and also by sunlight. Preferably, the bamboo materials of the present invention are formed of 100% bamboo fibres although mixtures with other cellulose fibres are also contemplated.
[0033] The bamboo may also be in the form of a paper towel, towelette, wipe or pad which may have the same applications as paper towels. The bamboo fibres may also be used as a clothing fabric, optionally in combination with other known fibres, to make garments, such as socks and hospital gowns. For example, socks made from bamboo fibres impregnated with the bioflavonoid compositions described herein can help reduce foot odour. The bioflavonoid impregnated bamboo fibres are activated when they come into contact with moisture from the foot. For hospital gowns, the bioflavonoid composition is activated when the gowns come into contact with, for example, blood or urine.
[0034] Fabrics made from bamboo fibres which are impregnated with the bioflavonoid compositions described herein are very useful in hospital or care home environments. For example, the bamboo fabric can be used for bedding sheets, surgical drapes, curtains and the like where it is desirable to use a material with antimicrobial properties.
[0035] Paper fibre fabrics can be used instead of the bamboo fibre fabrics described herein; however, the bamboo fibre fabrics are preferred as these fabrics are more durable than paper fibre fabrics.
[0036] Paper towels, bamboo towels and the like, may be heated, for example by using a microwave, in order to provide a hot towel. These hot towels may be disposable and/or re-heatable and can be used in restaurants, hotels and on planes.
[0037] The bioflavonoid impregnated paper and/or bamboo fibres of the invention can also be provided in the form of a face mask, such as a respiratory mask or surgical mask, to provide the user with enhanced protection against inhaling bacteria and viruses or to prevent or reduce the spread of bacteria and viruses. The face masks may be reusable or disposable. Methods of manufacturing face masks are well known in the art.
[0038] Bioflavonoid impregnated bamboo and/or paper fibres can be used in the form of single or multi-ply food pads. Such food pads are often found in the bottom of food packaging and can also be referred to as napkins or blankets. The use of these food pads is particularly desirable in food packaging containing food with a short shelf life, for example meat or fruit. The food product, for example, the meat or fruit generally sit on top of the food pad within the packaging. The bioflavonoid impregnated food pad provides a dramatic reduction in the number of bacteria such as Salmonella, E. coli and Campylobacter which cause foods such as meat and fresh fruit to decay, reducing their shelf life. The bioflavonoid impregnated food pads are particularly suitable in the packaging of meats, including poultry (e.g. chicken or turkey), lamb, beef and pork; fish, including salmon and prawns; and fruits including soft fruits such as blackberries, raspberries, loganberries, strawberries and the like.
[0039] Cardboard is heavy duty paper and may include a single thick sheet of paper or more complex configurations such as multiple corrugated and uncorrugated layers which tend to by more durable than regular paper. The cardboard of the present invention will generally be of a depth of less than about 1 cm. The impregnated cardboard can be used in packaging, for example food packaging.
[0040] The cellulosic fibrous materials of the present invention are provided in a dry form and are activated when they are wetted, i.e. when the material comes into contact with moisture, such as a liquid. The liquid may be, for example, water, body fluids, for example sweat, blood or urine, fruit juice, cooking juices and the like. The materials can be wetted before being applied to a surface to be cleaned, for example, by applying water to the material before using on a surface. Alternatively, the materials are activated during use, for example, when drying hands moisture is transferred onto the material or when using the material to wipe down a wet surface.
[0041] The materials are provided in a substantially dry form and are preferably dried by heating to constant mass.
[0042] Preferably, the amount of bioflavonoid coating impregnated in the material is uniform throughout the material.
[0043] The bioflavonoid compositions described herein are biodegradable and can be impregnated into biodegradable materials such as biodegradable paper, bamboo fibres and the like to provide environmentally friendly products.
[0044] The bioflavonoid compositions described herein show activity against a wide range of organisms including gram positive bacteria, gram negative bacteria, fungi, virus, protazoans and insect parasites. The compositions may be employed against difficult bacteria such as methicillin resistant Staphylococcus aureus (MRSA), Clostridium difficile ( C. diff ), Helicobacter pylori ( H. pylori ), and vancomycin resistant enterobacteria. The compositions may also be used against norovirus and other pathogens whereby transmission is by contact on air. In particular, the compositions described herein show activity against E. coli, S. aureus, Salmonella, B. subtilis and P. aeruginosa.
[0045] According to a second aspect of the invention, there is provided a process for impregnating the materials described herein with the bioflavonoid compositions described herein. Impregnation is the partial or total saturation of a material, although total saturation is preferred. In particular the material is a thin material. A thin material is defined as having a depth of less than about 1 cm. Impregnation may be after manufacture of the thin material or it may occur during manufacture of the thin material, for example, impregnation of the cellulose fibres before being formed into the material.
[0046] If impregnating pre-formed cellulosic fibrous material, the process involves immersing the material, in the bioflavonoid composition to totally or partially saturate the material with the composition. The material may then be rolled, squeezed or wrung to remove any excess of the composition. The material is then dried, either by air drying naturally, oven drying or by mechanical drying. The equipment used to mechanically dry materials will be known to those skilled in the art as will alternative drying methods. The process results in a dry material which can then be packaged as desired and later activated by wetting. Alternatively, the cellulosic fibres used to produce the material may first be immersed in the bioflavonoid composition to totally or partially saturate the fibres with the composition which are then dried either before or after being formed into materials such as paper or cardboard by methods known in the art.
[0047] Alternatively, the materials may be impregnated by spraying the bioflavonoid composition onto the materials so that the composition impregnates the outer surface region of the material to achieve at least partial impregnation. Spraying may also be used to impregnate the fibres during manufacture or extraction, before being formed into the materials of the invention.
[0048] A particular method for impregnating paper towels is disclosed in Example 3. Fibrous bamboo products may also be impregnated in the same way as disclosed in Example 3.
[0049] Preferably, the processes described above provide uniform bioflavonoid impregnation throughout the cellulosic fibrous material. A concentration of between 0.005 and 0.75%, preferably between 0.005 and 0.5%, more preferably between 0.025% and 0.5%, even more preferably between 0.025 and 0.1% of the bioflavonoid composition is used. The compositions described herein are water soluble and water can be used to dilute the bioflavonoid composition to the desired concentration.
[0050] According to a third aspect of the invention, there is provided a method of reducing the bacterial load on a surface. The method of reducing the bacterial load on a surface is provided by two mechanisms. Firstly, the kill is achieved by the action of the bioflavonoid compositions and then secondly the contaminants are mechanically removed by the material itself via the action of placing on and wiping the surface, i.e. mechanical wiping.
[0051] The surface may be any bioactive surface and could be either a human or non-human surface. For example, a human surface may include the skin on the hands, feet or face. A non-human surface may include any surface of sanitary importance which may carry a contaminant, for example, the surfaces found in schools, bathrooms, kitchens, factories, for example food factories, laboratories, hospitals and the like.
[0052] For food contact the Environmental Protection Agency (EPA) requires the active to effect a 5 log reduction of the challenge organism in 30 seconds. Preferably, the materials of the present invention effect at least a 5 log reduction of the bacteria load on a surface in 30 seconds.
[0053] According to a fourth aspect of the invention, there is provided a packaged product wherein the product is formed of a dry cellulosic fibrous material impregnated with a bioflavonoid composition. The product and the bioflavonoid composition are as described in the first aspect of the invention.
[0054] The cellulosic product may be individually packaged. Alternatively, the product may be packaged as part of a multi-pack. Known packaging methods and materials may be used to package the products of the present invention, for example conventional filmic agents or cardboard boxes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0055] In order that the invention may be more fully understood it will now be described, by way of example only, and with reference to the following Figure(s), in which:
[0056] FIG. 1 is a graph showing the results of the effects of different dilutions of the Citrox BC active dried onto Bounty® brand paper towels on S. aureus activity.
[0057] FIG. 2 is a graph showing the results of the effects of different dilutions of the Citrox BC active dried onto Bounty® brand paper towels on E. coli activity.
DETAILED DESCRIPTION
[0058] The bioflavonoid content may comprise 40-50%, for example about 45% wt/wt of the bioflavonoid composition. A suitable source of a bioflavonoid composition is herein referred to as “HPLC 45” or “Citrox BC” of which about 45% (of the total composition of HPLC 45/Citrox BC) comprises bioflavonoids. The bioflavonoids are in admixture with biomass residues of extraction from bitter oranges, such as pectins, sugars and minor organic acids, which make up the remaining 55%. HPLC 45 is available from Exquim (a company of Grupo Ferrer) as Citrus Bioflavonoid Complex 45% HPLC.
[0000]
TABLE 1
The mixture of bioflavonoids in HPLC 45
%
bioflavonoid in mixture
Bioflavonoid
with biomass
Neoeriocitrin
1.1
Isonaringin
1.2
Naringin
23.4
Hesperidin
1.4
Neohesperidin
12.5
Neodiosmin
1.4
Naringenin
1.5
Poncirin
2.0
Other (Rhiofolin)
0.5
EXAMPLES
[0059] Staphylococcus aureus was chosen as a representative gram positive organism. This organism is found on mammalian skin and is, therefore, shed into the surrounding environment. E. coli was chosen as the representative of the gram negative enteric bacteria. This organism is found in the digestive tract of birds, mammals and reptiles. Its presence in the environment signals fecal contamination. Pseudomonas aeruginosa was chosen to represent the non-enteric gram-negative bacteria. This genera of bacteria is present in water with related species representing major plant pathogens and human opportunistic pathogens. Bacillus subtilis was chosen as the representative gram positive spore-formers. This bacterium is found in soil and water but is also ubiquitous in the environment. This species forms endospores as a survival mechanism. Bacterial endospores are the most resistant form of life on Earth and, therefore, represent an ongoing concern for sanitation, disinfection and sterilisation processes. Endospores represent the “ultimate” challenge for any antimicrobial agent.
Example 1
Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC)
Procedure
[0060] A pure culture of a single microorganism is grown in an appropriate broth. The culture is standardized using standard microbiological techniques to have a concentration of very near 1 million cells per millilitre. The more standard the microbial culture, the more reproducible the test results. The antimicrobial agent is diluted a number of times, 1:1, using sterile diluents. After the antimicrobial agent has been diluted, a volume of the standardised inoculums equal to the volume of the diluted antimicrobial agent is added to each dilution vessel, bringing the microbial concentration to approximately 500,000 cells per millilitre. The inoculated, serially diluted antimicrobial agent is incubated at an appropriate temperature for the test organism for a pre-set period, usually 18 hours. After incubation, the series of dilution vessels is observed for microbial growth, usually indicated by turbidity and/or a pellet of microorganisms in the bottom of the vessel. The last tube in the dilution series that does not demonstrate growth corresponds with the minimum inhibitory concentration (MIC) of the antimicrobial agent.
[0061] In order to differentiate between a microbiostatic agent (bacteria are not killed just inhibited) and a microbiocidal agent (bacteria are killed) an MBC test is performed. When a microbiostatic agent is removed or neutralized, previously inhibited bacteria begin to grow again. Each well showing no growth/turbidity in the MIC test is sub-cultured on media that contains no biocide. Any microbial growth resulting from this test indicates that, at that concentration, the active is microbiostatic. If the subculture results in no bacterial regrowth, then, at that concentration, the active is microbiosidal. The range of concentration of Citrox BC active tested was 0.075-0.75%.
Discussion of Results
[0062] The MIC test is an established “screen” for the biostatic (and possibly also biocidal) activity of liquid antimicrobials. It is often used to find the appropriate concentrations of an antimicrobial active to use for further efficacy testing. Performing both the MIC and MBC test will enable one to differentiate between a biocidal or biostatic mode of action. Depending on the concentration of active used and the contact time an active will often demonstrate both biostatic and biocidal modes of action.
[0063] The range of Citrox BC active tested was 0.075%-0.75%. For P. aeruginosa , no MIC value was obtained as all concentrations of the Citrox BC active tested showed no turbidity (Table 2).
[0064] MCB testing showed that all concentrations were also bactericidal for B. subtilis , there was also no MIC value obtained demonstrating that inhibition of growth took place at all concentrations tested. The MBC value obtained for B. subtilis was 0.315% Citrox BC active. This means that concentrations ranging from 0.075% to 0.315% are bacteristatic and all concentrations of the Citrox BC active greater than or equal to 0.315% are bactericidal.
[0065] These results indicate that gram negatives like P. aeruginosa are more easily killed by the Citrox BC active than the gram positive B. subtilis .
[0000]
TABLE 2
MIC/MBC Testing
%
MIC
MBC
Citrox
(G/NG)
(CFU/mL)
BC
P.a.
B.s.
P.a.
B.s.
0
G
0
0
0
0.075
NG
G
0
4.2 × 10 2
0.095
NG
G
0
3.1 × 10 2
0.115
NG
G
0
3.3 × 10 2
0.135
NG
G
0
3.5 × 10 2
0.155
NG
G
0
3.6 × 10 2
0.175
NG
G
0
2.4 × 10 2
0.195
NG
G
0
1.5 × 10 2
0.215
NG
G
0
1.3 × 10 2
0.235
NG
G
0
1.6 × 10 2
0.255
NG
G
0
40
0.275
NG
G
0
40
0.295
NG
G
0
1
0.315
NG
NG
0
0
0.335
NG
NG
0
0
0.355
NG
NG
0
0
0.375-0.750
NG
NG
0
0
G = Growth,
NG = No Growth
P.a. = Psuedomonas aeruginosa
B.s. = Bacillus subtilis
Example 2
Time Kill Test
Procedure
[0066] All timed kill tests were performed using a standard viable count procedure. Reference NB X34689.
[0067] The following neutralising solution was used in all kill tests.
Tween 80-3%
Saponin-3%
Histidine-0.1%
Cysteine-0.1%
Rationale
[0068] A timed kill test assesses the amount of time it takes to kill a defined population of microorganisms. A wide variety of microorganisms are killed by the Citrox BC active. An important first step in characterising this active for use in an antimicrobial towel is to verify the kill claims. Claims for efficacy are based on the number of bacterial killed within a defined time frame. The most rigorous claims are those made for food contact where the active must affect a 5 log reduction of the challenge organism in 30 seconds.
Discussion of Results
Example 2(a)
Timed Kill Test: 10 Minute Contact Time
[0069] Bacterial kill kinetics are affected by bacterial numbers, the concentration of active used and the contact time. In order to determine the most effective range of the Citrox BC active, S. aureus was used in a 10 minute kill test to assess the efficacy of various concentrations of the Citrox BC active. A >6.56 log reduction was observed for all concentrations (0.45-0.65%) of the Citrox BC active tested (Table 3).
[0070] When B. subtilis was used as a challenge organism, 0.7% Citrox BC was required to effect a >5 log reduction in 10 minutes (Table 4). Based on previous tests, 0.5% active is the most effective for general use.
[0000]
TABLE 3
Time Kill Test: S. aureus , 10 min.
% Citrox
Log10
Log
BC
CFU/mL
CFU/mL
Reduction
0
7.4 × 10 6
6.86
0
0.45
<2
0.3
6.56
0.5
<2
0.3
6.56
0.55
<2
0.3
6.56
0.6
<2
0.3
6.56
0.65
<2
0.3
6.56
0.65 +
6.6 × 10 6
6.81
0.05
neutralizer
[0000]
TABLE 4
Time Kill Test: B. subtilis , 10 min.
%
Citrox
Log10
Log
BC
CFU/mL
CFU/mL
Reduction
0
1.1 × 10 6
6.04
NA
0.5
2.9 × 10 4
4.4
1.64
0.7
<2
0.3
5.74
Example 2(b)
Timed Kill Test: 30 Second Contact Time
[0071] Timed kill studies using E. coli, P. aeruginosa and S. aureus were performed using 0.5% Citrox BC active with a contact time of 30 seconds. Log reductions of >6.4 were seen for all organisms (Table 5). This confirms that this active would meet the criteria for use in food contact situations.
[0000]
TABLE 5
Time Kill Test: 30 seconds
E. coli
P. aeruginosa
S. aureus
% Citrox BC
0
0.5
0
0.5
0
0.5
CFU/mL
5.1 × 10 6
<2
6.4 × 10 7
<2
7.4 × 10 6
<2
Log10
6.7
<0.3
7.8
<0.3
6.8
<0.3
CFU/mL
Log
NA
6.5
NA
7.3
NA
6.5
Reduction
Example 2(c)
Timed Kill Test: Sporicidal Activity
[0072] As stated above, the ultimate test for any antimicrobial active is the ability to kill spores. Any chemical or process that kills a bacterial spore is, by definition, a sterilant. In order to assess if the Citrox BC active was sporicidal, a kill test was performed on an actual spore suspension. Citrox BC, over a range 0.5% to 1.5%, was tested over a 1 hour time period. There were some limitations to this test. The spore suspension ( B. subtilis , ATCC 6633, 6.4×10 4 CFU/pellet, Microbiologics) in the test was only at ˜2×10 4 CFU/ml, limiting the log reduction calculation. The lyophilized pellets were found to contain charcoal, a substance known to neutralise the bioflavonoid component of the Citrox BC active. With those limitations, approximately a 2 log reduction in spores was demonstrated. This indicates that the Citrox BC active has definite activity against spores. Spore suspensions at a higher titer without a charcoal additive should be used to investigate this activity further.
Example 3
Surface Testing Using Paper Towel Impregnated with Citrox BC Active
1) Procedure: Adding Citrox BC to Paper Towel
[0073] Bounty® (“Bounty” is a registered trademark of Procter & Gamble) brand paper towels were used to make the dry antimicrobial towels. Bounty® paper towels are a conventional, commercially available paper towel product. Citrox BC active concentrate was diluted to desired concentrations. One paper towel was immersed completely into the diluted active and then wrung out by hand. The towel was dried overnight.
[0000] 2) Procedure: Weight of Citrox BC Active Dried onto Bounty® Brand Paper Towel
[0074] Bounty® brand paper towels were dried to a constant weight in a 54° C. oven. Various dilutions of the Citrox BC active were dried onto Bounty® brand paper towels as described above. The towels were dried at room temperature overnight. The treated towels were then dried to a constant weight at 54° C. The weight difference between the untreated and treated towels is presumed to be the weight of the Citrox BC active.
3) Procedure: For Testing Affect of Administration of Impregnated Paper Towels to a Surface
[0075] Using the lab bench top as a representative hard, non-porous surface, a grid was marked off using tape. Cotton-tipped swabs saturated with a broth culture of the challenge organism were used to inoculate the surface and air dried. Paper towels treated with dilutions of the Citrox BC active were wetted and then used to clean the inoculated bench top. The bench top was visibly wet for 3 minutes (contact time) and then allowed to completely air dry. RODAC (Replicate Organism Detection and Counting) plates were used to sample the cleaned surface for surviving bacteria. The plates were incubated overnight at a temperature appropriate to the challenge organism. Colonies were counted and the number used to calculate CFU/cm 2 . Results were calculated by averaging the counts from five 3″×3″ “grid squares”.
4) Procedure: RODAC Sampling
[0076] A RODAC plate is used to touch the surface to be sampled after which the plate is incubated at an appropriate temperature. There are nutrients in the media that promote the growth of a variety of microbes. Lecithin and Polysorbate 80 are incorporated in the agar and function as disinfectant/sanitizer neutralisers. The type and number of microorganisms is detected by the appearance of colonies on the surface of the agar medium. Collection of samples from the same area before and after cleaning and treatment with a disinfectant permits the evaluation of sanitary procedures.
Results
[0077] Paper towels wetted with water and containing no Citrox BC active were assessed for the ability to remove bacteria from a contaminated hard surface. The results for this control (i.e. unimpregnated paper towels) are shown by the bar labelled “0” in FIGS. 1 and 2 . FIGS. 1 and 2 show the results for both S. aureus and E. coli . Paper towels containing dilutions of the Citrox BC active greater than 1:200 were able to reduce the levels of S. aureus from >50 CFU/cm 2 to <1 CFU/cm 2 . The paper towels containing dilutions of the Citrox BC active greater than 1:200 were able to reduce the levels of E. coli from >7 CFU/cm 2 to <1 CFU/cm 2 .
[0078] These results show that a dry antimicrobial towel are activated by wetting.
Discussion of Results
[0079] Different dilutions of the Citrox BC active were dried onto Bounty® brand paper towels. These treated towels were used to decontaminate a lab bench heavily inoculated with bacteria. The ability of the treated towels to affect a decrease of contaminants on the lab bench was evaluated using RODAC plates.
[0080] A method was developed to assess ability of a paper towel impregnated with the Citrox BC active to reduce bacterial numbers on a contaminated hard surface. RODAC plates are recommended for the detection and enumeration of microorganisms present on surfaces of sanitary importance. RODAC plates are specially constructed so that an agar medium can be overfilled producing a dome-shaped surface that can be pressed on a surface for sampling its microbial content. RODAC plates are used in a variety of programs to establish and monitor cleaning techniques and schedules.
[0081] When using a paper towel plus an antimicrobial active, one must keep in mind that removal of bacteria from a contaminated surface occurs by two mechanisms: first is the kill achieved by the action of the antimicrobial active and second is mechanical removal of the contaminants by the paper towel itself.
[0082] Lab scale antibacterial towels were used to calculate the weight of the Citrox BC active dried onto the towels. The weight of active present on the towel (Table 6) can be used as a starting point for cost analysis.
[0000]
TABLE 6
Weight of Citrox BC active dried onto Bounty ® paper towel
Post-
Ave. wt.
Citrox
Pre-
treatment
of BC
BC
treatment
Dry
active
Dilution
Dry Weight
Weight
Difference
(g/towel)
Std Dev
1:150
4.32547
4.31821
−0.00726
0.00388
0.006875
4.31226
4.32089
0.00863
4.31476
4.32400
0.00924
4.32424
4.32607
0.00183
4.32625
4.33321
0.00696
1:100
4.30877
4.35320
0.04443
0.05244
0.010257
4.30530
4.36125
0.05595
4.32380
4.37021
0.04641
4.30800
4.35446
0.04646
4.30435
4.37329
0.06895
1:50
4.31739
4.49804
0.18065
0.20090
0.046566
4.38309
4.51604
0.13295
4.31517
4.54191
0.22674
4.31539
4.52472
0.20933
4.32305
4.57787
0.25482 | Cellulosic fibrous materials are described which are impregnated with a bioflavonoid composition, the bioflavonoid content of the composition comprising at least naringin and neohesperidin. The use of such impregnated materials is also described, for example as paper or bamboo towels and cardboard, as well as the process for impregnating the materials. | 3 |
BACKGROUND OF THE INVENTION
1. Technical Field
The invention relates generally to semiconductor memory fabrication, and more particularly, to a self-aligned strap for embedded trench memory, e.g., a trench capacitor, on a hybrid orientation technology (HOT) substrate and related method.
2. Background Art
As technologies become increasingly complex, demand for integrated circuits (IC) having more functionality is growing. In order to provide ICs with optimum designs, high-performance complementary metal-oxide semiconductor (CMOS) devices are required with additional features such as embedded memory devices like dynamic random access memory (DRAM). A challenge that arises relative to providing all of these features is that each feature is optimized under different conditions. For example, high-performance CMOS devices may be completed on silicon on insulator (SOI) wafers but memory devices may be built in bulk silicon.
Conventional techniques exist for making patterned SOI (part bulk and part SOI) wafers for the purposes of merging the best of “bulk technologies” with the best of “SOI technologies.” One such technique that utilizes this approach integrates DRAM in SOI. In this case, the DRAM array blocks are built in bulk silicon and logic is built in the SOI. The use of SOI and bulk silicon allows for different crystalline orientations on a surface of the substrate. This process technology is referred to as hybrid (surface) orientation technology (HOT).
One challenge relative to HOT technology and embedded memory is efficiently generating a low resistance strap to electrically couple a source/drain region of a transistor on the SOI substrate to an electrode of the embedded memory (e.g., trench capacitor) in the bulk silicon. In particular, conventional techniques require extra masks and cannot generate the strap in a self-aligned manner. Accordingly, the conventional techniques present a complex and costly approach.
SUMMARY OF THE INVENTION
Structures including a self-aligned strap for embedded trench memory (e.g., trench capacitor) on hybrid orientation technology (HOT) substrate, and related method, are disclosed. One structure includes a hybrid orientation substrate including a semiconductor-on-insulator (SOI) section and a bulk semiconductor section; a transistor over the SOI section; a trench capacitor in the bulk semiconductor section; and a self-aligned strap extending from a source/drain region of the transistor to an electrode of the trench capacitor. The method does not require additional masks to generate the strap, results in a self-aligned strap and improved device performance. In one embodiment, the strap is a silicide strap.
A first aspect of the invention provides a structure comprising: a hybrid orientation substrate including a semiconductor-on-insulator (SOI) section and a bulk semiconductor section; a transistor over the SOI section; a trench capacitor in the bulk semiconductor section; and a self-aligned strap extending from a source/drain region of the transistor to an electrode of the trench capacitor.
A second aspect of the invention provides a method comprising: providing a hybrid orientation substrate including a semiconductor-on-insulator (SOI) section and a bulk semiconductor section; forming a trench across an interface between the SOI section and the bulk semiconductor section, the trench stopping on a buried insulator of the SOI section and extending into the bulk semiconductor section; depositing a node dielectric and a first conducting portion in the trench to form a trench capacitor in the trench; recessing the trench capacitor; forming a second conducting portion adjacent to a semiconductor layer of the SOI section; forming a trench isolation over the trench capacitor and the second conducting portion; forming a transistor on the SOI section by which a portion of the trench isolation is removed over the second conducting portion adjacent to the semiconductor layer; and forming a self-aligned strap between the transistor and the trench capacitor.
A third aspect of the invention provides a structure comprising: a hybrid orientation substrate including a semiconductor-on-insulator (SOI) section and a bulk semiconductor section; a transistor over the SOI section; a trench capacitor in the bulk semiconductor section, the trench capacitor including a first portion in the bulk semiconductor and a second portion extending from the first portion over a portion of a buried insulator of the SOI section; and a self-aligned strap extending from a source/drain region of the transistor to an electrode of the trench capacitor, the self-aligned strap including at least a portion of the second portion.
The illustrative aspects of the present invention are designed to solve the problems herein described and/or other problems not discussed.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of this invention will be more readily understood from the following detailed description of the various aspects of the invention taken in conjunction with the accompanying drawings that depict various embodiments of the invention, in which:
FIGS. 1-8 show one embodiment of a method of forming a self-aligned strap on a hybrid orientation technology (HOT) substrate according to the invention, with FIG. 8 showing a structure including the self-aligned strap according to one embodiment of the invention.
It is noted that the drawings of the invention are not to scale. The drawings are intended to depict only typical aspects of the invention, and therefore should not be considered as limiting the scope of the invention. In the drawings, like numbering represents like elements between the drawings.
DETAILED DESCRIPTION
Turning to the drawings, FIGS. 1-8 show one embodiment of a method of forming a self-aligned strap 180 ( FIG. 8 ) on a hybrid orientation technology (HOT) substrate 100 (hereinafter “hybrid orientation substrate”) according to the invention. As used herein, “orientation” refers to the crystallographic structure or periodic arrangement of silicon atoms on the surface of a wafer. FIG. 1 shows providing a hybrid orientation substrate 100 including a semiconductor-on-insulator (SOI) section 102 and a bulk semiconductor section 104 . SOI section 102 may include a semiconductor layer 106 (e.g., silicon) and a buried insulator layer 108 (e.g., silicon oxide) atop semiconductor substrate 110 (e.g., silicon), from which bulk semiconductor section 104 extends. Bulk semiconductor section 104 includes a semiconductor layer 112 atop semiconductor substrate 110 . As indicated, semiconductor layer 106 of SOI section 102 has a different orientation, e.g., ( 100 ), than bulk semiconductor section 104 , e.g., ( 110 ). Other orientations may also be employed. Hybrid orientation substrate 100 can be generated in any now known or later developed fashion. For example, SOI section 102 may be provided, and semiconductor layer 104 and buried insulator layer 106 etched away, and semiconductor layer 112 epitaxially grown from semiconductor substrate 110 . SOI section 102 and bulk section 104 may be separated by an interface layer 114 (e.g., silicon oxide or silicon nitride).
“Semiconductor” as used herein may include silicon, germanium, silicon germanium, silicon carbide, and those consisting essentially of one or more III-V compound semiconductors having a composition defined by the formula Al X1 Ga X2 In X3 As Y1 P Y2 N Y3 Sb Y4 , where X1, X2, X3, Y1, Y2, Y3, and Y4 represent relative proportions, each greater than or equal to zero and X1+X2+X3+Y1+Y2+Y3+Y4=1 (1 being the total relative mole quantity). Other suitable substrates include II-VI compound semiconductors having a composition Zn A1 Cd A2 Se B1 Te B2 , where A1, A2, B1, and B2 are relative proportions each greater than or equal to zero and A1+A2+B1+B2=1 (1 being a total mole quantity). Furthermore, a portion or entire semiconductor substrate may be strained. For example, SOI layer 106 and/or semiconductor layer 112 may be strained.
As shown in FIG. 2 , a trench 120 is formed across interface 114 between SOI section 102 and bulk semiconductor section 104 . Trench 120 may be formed in any now known or later developed manner. For example, as shown, a pad layer 124 (e.g., of silicon oxide and/or silicon nitride) is formed (e.g., deposited), a hardmask 126 (e.g., boro-silicate glass) is deposited, patterned and etched to a surface (not shown) of SOI section 102 and bulk semiconductor section 104 . Further etching is then performed to open trench 120 . Trench 120 stops on buried insulator 108 after removal of silicon layer 106 of SOI section 102 , but extends into bulk semiconductor section 104 (including into semiconductor substrate 110 ). Hardmask 126 is then removed in any now known or later developed manner, e.g., a reactive ion etch (RIE). As used herein, “depositing” may include any now known or later developed techniques appropriate for the material to be deposited, e.g., chemical vapor deposition (CVD), low-pressure CVD (LPCVD), plasma-enhanced CVD (PECVD), semi-atmosphere CVD (SACVD) and high density plasma CVD (HDPCVD), rapid thermal CVD (RTCVD), ultra-high vacuum CVD (UHVCVD), sputtering deposition, ion beam deposition, electron beam deposition, laser assisted deposition, thermal oxidation, thermal nitridation, spin-on methods, physical vapor deposition (PVD) or atomic layer deposition (ALD). A portion of interface layer 114 above buried insulator layer 108 may be removed during the process of etching trench 120 .
FIG. 3 shows depositing a node dielectric 130 and a first conducting portion 132 of conducting material in trench 120 to form a trench capacitor 134 in trench 120 . Node dielectric 130 may include any now known or later developed insulator appropriate for forming a trench capacitor 134 , e.g., silicon oxide, silicon nitride, silicon oxynitride, high-k material having a relative permittivity above about 10, or any combination of these materials. Examples of high-k material include but are not limited to metal oxides such as Ta 2 O 5 , BaTiO 3 , HfO 2 , ZrO 2 , Al 2 O 3 , or metal silicates such as Hf A1 Si A2 O A3 or Hf A1 Si A2 O A3 N A4 , where A1, A2, A3, and A4 represent relative proportions, each greater than or equal to zero and A1+A2+A3+A4 (1 being the total relative mole quantity). First conducting portion 132 may include, for example, amorphous silicon, polycrystalline silicon (hereinafter “polysilicon”), germanium, silicon germanium, a metal (e.g., tungsten, titanium, tantalum, ruthenium, cobalt, copper, aluminum), a conducting metallic compound material (e.g., tungsten silicide, tungsten nitride, titanium nitride, tantalum nitride, ruthenium oxide, cobalt silicide, nickel silicide), or any suitable combination of these materials. First conducting portion 132 may further include dopants. In one embodiment, first conducting portion 132 includes doped polysilicon. Methods for forming the node dielectric 130 and first conducting portion 132 include but are not limited to thermal oxidation, chemical oxidation, thermal nitridation, atomic layer deposition (ALD), low-pressure chemical vapor deposition (LPCVD), plasma enhanced chemical vapor deposition (PECVD), high density plasma chemical vapor deposition (HDPCVD), sub-atmospheric chemical vapor deposition (SACVD), rapid thermal chemical vapor deposition (RTCVD), limited reaction processing chemical vapor deposition (LRPCVD), ultrahigh vacuum chemical vapor deposition (UHVCVD), metalorganic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), physical vapor deposition, sputtering, plating, evaporation, ion beam deposition, electron beam deposition and/or laser assisted deposition.
As known in the art, trench capacitor 134 includes an electrode 136 within silicon substrate 110 separated by node dielectric 130 from another electrode 138 formed by first conducting portion 132 inside trench 120 . Part or entire semiconductor substrate 110 may be doped and therefore electrode 136 may be placed in a doped region. Planarization (e.g., chemical mechanical polishing (CMP)) may be conducted at this point after depositing first conducting portion 132 .
FIG. 4 shows recessing trench capacitor 134 , which may include etching first conducting portion 132 and removing any exposed node dielectric 130 . Trench capacitor 134 is shown recessed to just below a surface 140 of buried insulator layer 108 ; however, it may be at other locations relative to surface 140 , e.g., higher or lower.
FIG. 5 shows forming a second conducting portion 150 of conducting material adjacent to silicon layer 106 of SOI section 102 . Second conducting portion 150 may include, for example, amorphous silicon, polycrystalline silicon (polysilicon hereinafter), germanium, silicon germanium, a metal (e.g., tungsten, titanium, tantalum, ruthenium, cobalt, copper, aluminum), a conducting metallic compound material (e.g., tungsten silicide, tungsten nitride, titanium nitride, tantalum nitride, ruthenium oxide, cobalt silicide, nickel silicide), or any suitable combination of these materials. Second conducting portion 150 may extend over first conducting portion 132 to silicon layer 106 . Trench capacitor 134 now includes first conducting portion 132 and second conducting portion 150 , as is described in greater detail herein. FIG. 6 shows forming a trench isolation 152 over trench capacitor 134 , including second conducting portion 150 . Trench isolation 152 may be formed using any technique, e.g., etching and then depositing a dielectric such as silicon oxide.
FIG. 7 shows forming a transistor 160 on SOI section 102 . A passive transistor 161 also may be formed at this point on isolation region 152 over trench capacitor 134 . Passive transistor 161 may be advantageous in self-alignment of strap 180 ( FIG. 8 ), but may not be necessary in all instances, e.g., trench isolation 152 and/or other materials may be used for self-alignment purposes. Each transistor 160 , 161 may be formed using any now known or later developed techniques. For example, pad layer 124 ( FIG. 6 ) may be removed (e.g., by etching or polishing), ion implantation may be performed to incorporate dopants (not shown) into a channel region 163 in semiconductor layer 106 , a gate dielectric layer 166 (e.g., hafnium silicate, hafnium oxide, zirconium silicate, zirconium oxide, silicon oxide, silicon nitride, silicon oxynitride, high-k material or any combination of these materials) may be deposited, a gate conductor layer 168 (e.g., polysilicon, metal or alloys thereof) may be deposited, and a gate 170 may be patterned and etched from gate dielectric layer 166 and gate conductor layer 168 . Spacer(s) 169 may be added as known in the art. It is during this later etching that portion 162 of trench isolation 152 is removed adjacent to silicon layer 106 to expose at least a portion of the top surface of second conducting portion 150 . Source/drain 164 then may be formed in silicon layer 106 adjacent to gate 170 by ion implantation. During the ion implantation process, dopants are also implanted into the exposed portion of second conducting portion 150 , forming a self-aligned doped strap 172 in second conducting portion 150 . One terminal of source/drain 164 is electrically connected to remaining portion of second conducting portion 150 through doped strap 172 . Note that transistor 161 does not include a source/drain region since it is formed on trench isolation 152 .
FIG. 8 shows forming a self-aligned strap 180 between transistor 160 and trench capacitor 134 . In one embodiment, the forming includes simultaneously forming silicide 182 in semiconductor layer 106 and at least a portion of doped strap 172 , i.e., in second conducting portion 150 . Silicide 182 , including but not limited to titanium silicide, nickel silicide, and cobalt silicide, may be formed using any now known or later developed technique, e.g., depositing a metal such as titanium, nickel, cobalt, annealing to have the metal reacts with silicon, and removing unreacted metal. Silicide 182 is formed in silicon layer 106 and doped strap 172 , e.g. of polysilicon, generating a silicide strap 180 . Strap 180 is thus self-aligned to trench capacitor 134 (and transistor 161 , where used) and transistor 160 . In another embodiment, the forming includes simultaneously incorporating dopants into semiconductor layer 106 and at least a portion of second conducting portion 150 , e.g., by simply forming source/drain region 164 and doped strap 172 . In this case, self-aligned strap 180 includes dopants.
FIG. 8 also shows one embodiment of a structure 200 according to the invention. Structure 200 includes hybrid orientation substrate 100 including SOI section 102 and bulk semiconductor section 104 , transistor 160 over SOI section 102 , trench capacitor 134 in bulk semiconductor section 104 , self-aligned silicide strap 180 extending from source/drain region 164 of transistor 160 to electrode 138 of trench capacitor 134 . Trench capacitor 134 includes first conducting portion 132 in bulk semiconductor section 104 and second conducting portion 150 . Second conducting portion 150 may extend from first conducting portion 132 and have a portion thereof extend over a portion 190 of buried insulator 108 of SOI section 102 . Self-aligned silicide strap 180 includes at least a portion of second conducting portion 150 . As shown in FIG. 8 , a surface 192 of silicide strap 180 in source/drain region 164 may be non-planar with a surface 194 of suicide strap adjacent to trench capacitor 134 . Trench isolation 152 isolates trench capacitor 134 from other structure (not shown). As noted above, trench isolation 152 may include passive transistor 161 thereover such that strap 180 is self-aligned between transistor 160 and passive transistor 161 . Trench isolation 152 may extend over trench capacitor 134 .
The foregoing description of various aspects of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously, many modifications and variations are possible. Such modifications and variations that may be apparent to a person skilled in the art are intended to be included within the scope of the invention as defined by the accompanying claims. | Structures including a self-aligned strap for embedded trench memory (e.g., trench capacitor) on hybrid orientation technology (HOT) substrate, and related method, are disclosed. One structure includes a hybrid orientation substrate including a semiconductor-on-insulator (SOI) section and a bulk semiconductor section; a transistor over the SOI section; a trench capacitor in the bulk semiconductor section; and a self-aligned strap extending from a source/drain region of the transistor to an electrode of the trench capacitor. The method does not require additional masks to generate the strap, results in a self-aligned strap and improved device performance. In one embodiment, the strap is a silicide strap. | 7 |
BACKGROUND OF THE INVENTION
The scope of the present invention is that of protection devices for a vehicle or structure against attack by a shaped-charge munition.
Protection devices which consist of supplementary armour, called reactive armour, are already known. In a known manner, this armour comprises a sheet of explosive placed between two metal plates (see, for example, patent U.S. Pat. No. 4,741,244).
The impact of the dart of a shaped charge on such an armour causes the initiation of the explosive and the projection of a metal plate against the dart.
The projected plate consumes the dart which reduces its piercing power with respect to the vehicle wall.
Such armours are efficient, but their detonating properties impose constraints from the safety and storage point of view. On functioning, they may also cause injury to the soldiers who are in the vicinity of the vehicle.
Moreover, their initiation causes a substantial shock to the vehicle which makes them ill-adapted to use on light vehicles or slightly-armoured vehicles. They are all the more ill-adapted in that they have a high mass.
The initiation is triggered by the impact of the shaped-charge dart itself, i.e. when the charge comes into contact with the vehicle. In this case it is primordial to provide the vehicle with a relatively substantial explosive mass to ensure that the dart is fully consumed, otherwise there is the risk that the residual effectiveness of the latter would be enough to cause damage to the vehicle.
Lastly, the effectiveness of this type of armour is not guaranteed when the dart hits the armour plate at a certain angle of incidence. Thus a dart perpendicular to a reactive armour would pierce it without being significantly diminished.
It is therefore difficult using known reactive armour to ensure the protection of vehicle roofs against attack from shaped-charge sub-munitions scattered by vectors such as artillery shells, rockets or missiles.
Protection devices are also known, for example by patents DE2409876 and DE2507351, which employ nets or chains design to cause the initiation of the shaped charge at a great distance from the vehicle.
Such devices are both heavy and unwieldy, they must be kept permanently deployed in order to be effective and thus prejudice the mobility and stealth of the vehicle.
SUMMARY OF THE INVENTION
The aim of the present invention is to propose a protection device for a vehicle, or for a structure such as a building, which does not have such disadvantages.
The invention thus provides an effective protection against attack by shaped-charge munitions whatever the angle of incidences of these charges.
The invention also enables such a protection to be applied to light vehicles or structures without the risk of inflicting injury to the occupying persons and without using explosive materials.
The invention also improves the effectiveness of known reactive armour, notably against warhead having several shaped charges mounted in tandem (charge described, for example, in patent FR2552870).
The subject of the invention is thus a protection device for a vehicle or structure against attack by shaped-charge munitions, a device characterised in that it comprises at least one deployable bag fastened to an outer wall of the vehicle or structure, a bag which can be inflated by means of a generator in response to the detection of an attack.
According to a first embodiment of the invention, the generator is a generator of a polymerizable foam, a foam which inflates the bag before solidifying.
According to another embodiment of the invention, the generator is a pressurized gas tank connected to the bag by a valve.
Each deployable bag may, with advantage, be placed in a case which is fastened to the outer wall of the vehicle or structure by a dismountable connecting means.
According to one alternative, the connecting means may be released from inside the structure or vehicle.
According to another embodiment of the invention, the deployable bag may cover a reactive armour. This alternative enables the effectiveness of the reactive armour to be improved against warheads having several shaped charges mounted in tandem.
The device according to the invention shall comprise at least one threat detector which could automatically control the inflation of at least one bag.
According to a practical embodiment, the device designed to protect a vehicle shall comprise at least one deployable bag placed on the vehicle roof.
It could comprise at least one deployable bag on at least one lateral or front wall of the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood after reading the description of the particular embodiments, a description made with reference to the appended drawings wherein:
FIG. 1 shows a view in profile of a vehicle fitted with a protection device according to the invention;
FIG. 2 is a top view of the vehicle shown in FIG. 1;
FIG. 2a shows a top view of a vehicle according to an alternate embodiment of the invention;
FIG. 3 shows a diagram of a case implemented in the device according to the invention;
FIG. 3a shows a diagram of a case according to an alternate embodiment of the invention;
FIGS. 4a and 4b show how the protection device according to the invention functions.
FIG. 5 is a cross-sectional view showing a release mechanism for the protection device of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
With reference to FIGS. 1 and 2, a vehicle 1, such as a light tracked armoured vehicle, comprises a chassis 2 on which a turret 3 is mounted. The tracks 4a and 4b are protected by side panels 5a, 5b.
This vehicle is fitted with a protection device according to the invention which comprises protection cases 6 distributed over the roof 3a and the sides 3b, 3c of the turret, as well as over the chassis 2 and the side panels 5a, 5b.
The protection device also comprises a threat detector 7 which is mounted on the roof 3a and which could, for example, comprise several radar systems set in different surveillance directions.
The purpose of the threat detector is firstly, to detect the approach of shaped-charge munitions and secondly, to determine the direction of attack (from the roof, from the left side or right side, or from the front).
The protection device lastly comprises an electronic control module (not shown) which capts the information sent by the threat detector and which determines which protection case or cases must be activated in response to the detected threat.
The electronic module will preferably be placed inside the vehicle and it could comprise a device to visualize the direction of the threat and a hand-driven back-up control to activate the cases.
FIG. 3 shows in diagram form a case 6 fastened to a wall 8 of the vehicle.
In this example, the case is of a roughly parallelepiped shape and is, for example, made of a plastic material (another shape could naturally be chosen for the case, for example, a cylindrical shape). It has fastening hooks 9 which enable it to be fastened in a dismountable manner onto the wall 8, for example, using screws.
The case 6 contains a gas generator 10 of the pyrotechnic type. This generator contains a gas-generating composition as well as an electric igniter (not shown). The composition will be selected from among compositions which generate a large volume of gas with a restricted rise in temperature, for example, a composition based on sodium azide.
The igniter is connected to an electronic trigger circuit 11 by a conducting wire 12.
The gas generator is designed to inflate a bag 14 which is folded up inside the case 6. The bag is pinched at its edge between a rim 15 of the case and a strap 16. The bag and the strap could be fastened to the case, for example, by bonding.
The bag is made of a material which is both flexible and strong, for example, a polyamide or Kevlar material, or in an elastic material such as an elastomer.
The technologies related to gas generators and to inflatable bags are well known in the field of motor vehicle safety. Reference could, for example, be made to patent EP529371 which discloses a material which may be used to make such a bag and to patents U.S. Pat. No. 5,062,367, FR2691706 and EP509655 which disclose gas generators which can be used in motor vehicle safety conditions.
The case is closed by a lid 17 made of a rigid plastic material (for example, of polyvinyl chloride), its thickness is chosen so that it is broken when the bag inflates.
An incipient fracture could, for example, be provided on the periphery of the lid 17 so as to make it easier to break.
The purpose of the trigger circuit 11 is to cause the initiation of the gas generator in response to a command received from the control module.
In the embodiment shown here, the trigger circuit receives commands from the control module by means of an antenna 13 housed in a groove arranged in the wall of the case 6.
In the event that the case is made of metal, the antenna shall be placed on the outside of the case.
The trigger circuit 11 shall comprise: a power source (such as a battery), a receiver stage, a decoding circuit, and a programmable memory in which information regarding the position of the case on the vehicle will be programmed.
This information is introduced when the case is mounted onto the vehicle, for example, by means of a multi-position switch. This enables the following cases to be differentiated: case on the roof, case on a left wall, case on a right wall, case on the chassis and to the front of the vehicle.
The trigger circuit 11 will also comprise a computer which enables the command received by radio from the control module to be compared with the positioning information programmed into the memory and enables the initiation of the gas generator to be commanded or not.
The mode of operation of the device according to the invention will now be described with reference to FIGS. 4a and 4b.
A rocket 18 passes over the vehicle 1 and releases shaped-charge sub-munitions above it (for example, bomblets of the type disclosed by patent FR2697079).
The threat detector 7 detects the approach of the sub-munitions 19 from above the vehicle.
In response to this threat, it commands the inflation of all the bags in the case 6 which are placed on the upper part of the vehicle, or on the turret roof and on the top of the chassis (notably on the front and side glacis plates).
FIG. 4b shows the vehicle after inflation of the bags in question. The volume of the bags has been chosen such that, after their deployment, they occupy a volume such that the sub-munitions are not able to come into contact with the vehicle, at least not on the vulnerable parts (turret, motorization).
The impact of a sub-munition on a bag will cause its initiation because of the deceleration which occurs. A gas pressure will be provided which gives enough rigidity to the bag to enable such an initiation to take place. The rigidity of the usual motor vehicle safety bags is enough to perform this function.
The volume of the bags is also chosen such that, upon impact of a sub-munition on a bag, the latter is found at a distance D from the vehicle wall which is greater than the distance of optimal efficiency of the charge (which is usually of around 2 to 4 calibres).
For 40 mm calibre sub-munitions, we may see that the bags merely have to ensure a distance D greater or equal to 160 mm to be able to significantly reduce the piercing capacity of shaped charges.
It may be noted that the incidence of impact of the sub-munition on the bag has no effect on the effectiveness of the protection, the initiation of the charge is ensured at a great enough distance from the vehicle.
The bags inflated by a pyrotechnic generator usually deploy in thirty or so milliseconds (motor vehicle technology). As may be seen, for a sub-munition falling at a velocity of 50 m/s, it is possible to effectively trigger the deployment of the bags when the nearest sub-munition is less than 2 m from the vehicle. It is therefore possible to choose a threat detector having a reduced range (from 2 to 5 m), thereby limiting the power consumption of the latter and decreasing the signature of the vehicle.
Furthermore, the inflation only occurs if required, i.e. when there is a very high probability that the vehicle will be hit by a sub-munition (the detection of the sub-munitions being carried out at a small distance).
In the event that the vehicle is attacked from the side or the front by a missile, a rocket or grenade, the threat detector will determine the direction of the attack and the control module will then activate the inflation of the bags in the cases placed to the front of the chassis or on the side walls in question (right or left) or possibly all the bags so as to counter a missile able to attack from the roof.
For a rocket or missile which travels at 300 m/s, the threat detector would have to have a range of around 50 m. Detection at this distance allows an inflation time of 150 milliseconds, which allows larger-sized bags to be envisaged or bags using a specific inflation technology such as that described hereafter.
Different alternatives are possible without departing from the scope of the invention.
It is possible to provide a different number of bags, possibly only one if its volume is appropriate for the type of protection required.
It is also possible to inflate the bags using a generator of polymerizable foam, for example, polyurethane foam, rather than a gas generator. This foam will solidify and will therefore give the bag greater rigidity. Moreover, the foam will act as a composite "armour" enabling the dart to be weakened, reducing even more its residual piercing capacity.
Patent WO8800882 discloses a foam which is particularly well adapted to the inflation of deployable bags, notably in the rapid creation of floats.
In this event, the performances of the detection means will naturally be adapted to the inflation and solidification times which are greater than those obtained with gas generators.
It is possible to provide bags of differing volumes or types according to their position on the vehicle so as to adapt the protection to the part of the vehicle under consideration.
Gas-inflated bags could thus be provided to protect the roof and foam-filled bags could be provided to protect the side walls.
It is also possible to ensure inflation of the bags by means of a pressurized gas tank 32, as shown in FIG. 3a.
In this event, connecting nozzles linking the different cases to the gas tank will be provided.
Each case will therefore comprise a valve 30 whose opening will be controlled by a trigger circuit in the case acting in response to a command sent by the control module.
It would also be possible to replace the radio links between the control module and the cases by wire links.
It is also possible to replace or to back-up the threat detector carried by the vehicle by another threat detector placed outside of the vehicle and which have a greater range, for example a surveillance radar.
Means could be provided, with advantage, to link the cases and the vehicle which can be released from inside the structure or vehicle.
Such an arrangement allows the different used cases to be discarded from the vehicle after the attack.
Fastening could, for example, be ensured by means of cylindrical rods 20 having a hook 21 at the end, hooks which would work in conjunction with bolts 22 integral with the vehicle and electrically-controlled at 23.
Springs 24 could, in this case, be provided to facilitate the ejection of the rods 20 and the cases 6 when the bolts 22 are released.
Given their reduced volume and mass, spare cases could be provided on-board the vehicle.
It is also possible to use cases which combine an inflatable bag with a reactive armour of a known type. Such an alternative will enable warheads having shaped-charges mounted in tandem (see, for example, patent FR2552870 which discloses such charges) to be countered. The front charge, generally of a small calibre will thus be triggered at a distance from the reactive armour by its coming into contact with the bag. It will not be able to trigger the explosive of the reactive armour which will thus maintain its full effectiveness to counter the main charge.
In concrete terms, for this alternative a case merely has to be designed in which the bottom is made of a reactive armour. The inflatable bag thus covers the reactive armour thereby protecting it.
The device according to the invention may naturally be used to protect immobile structures such as buildings and hangars, and mobiles shelters. | A device for protecting a vehicle or structure against attack by a shaped-charge munition includes at least one deployable bag fastened on an external wall of the vehicle or structure. The bag is inflated by a generator in response to the detection of an attack. As a result, the invention provides an effective protection against attack by shaped-charge munitions whatever the angle of incidence of these charges. | 5 |
TECHNICAL FIELD
This application relates to an iPhone frequency sensor/magnifier application, and other matters.
BACKGROUND
Many physical objects, particularly those having defined surfaces that are relatively wider than they are thick, are characterized by a resonant frequency, that is, a frequency at which those physical objects exhibit a maximum (or at least a local maximum) energy response to vibrations. For example, a wooden tabletop might, depending on its size, thickness, and the substance from which it is made, have a particular frequency at which it might vibrate, and at which it might amplify vibrations if those vibrations are applied to that tabletop at that frequency.
This can have the effect that a speaker, or a speaker in combination with an amplifier, can deliberately cause the tabletop to vibrate at a relative maximum, by emitting vibrations (such as sound) that match the resonant frequency of that tabletop.
This can also have the effect that a sensor, or a sensor in combination with an amplifier, can detect or otherwise determine the resonant frequency of a tabletop on which it sits, in response to vibrations of the tabletop and in response to whether that sensor detects relative amplification or relative damping of those vibrations.
BRIEF DESCRIPTION OF THE DISCLOSURE
This application provides techniques, including devices and methods, which can determine a resonant frequency and possibly other characteristics of the object. For example, devices and methods as described herein can determine a resonant frequency of a surface upon which a frequency device (as described herein) is placed, and can in response thereto, determine useful information about that surface, such as its size, thickness, and construction materials included in that surface.
In one embodiment, one or more devices as described herein can emit one or more selected frequencies, and can detect a response of an object to which the devices are coupled, such as when the devices are placed upon a surface of the object. In response to this information, the devices can determine useful information about the object. The device can adjust its operation in response to information about the object, which can have the effect of improving performance of the device in one or more characteristics. For example, a speaker can emit vibrations at one or more known frequencies and can, in response to whether the tabletop amplifies or dampens vibrations at those frequencies, determine whether those frequencies include one or more resonant frequencies of the tabletop. In response to the resonant frequencies of the tabletop, the speaker can use the tabletop as an alarm or speaker, or as a center frequency for sonic output (such as a center frequency for playing music).
This application provides techniques, including devices and methods, which can sense acoustic vibrations from an object, such as received from a finger or stylus applied to the object, from a frequency emitted by a device applied to the object, or from a swept-sinusoid signal emitted by a device applied to the object. For example, devices and methods as described herein can sense impulse vibrations from an object coupled to a device having an inertial response sensor, and can in response thereto, determine useful information about those vibrations, such as their duration, location, volume, and materials used to induce those vibrations.
In one embodiment, one or more devices as described herein can receive one or more impulse vibrations from an object, such as using an accelerometer or another inertial response sensor (such as a gyroscope or otherwise), and can translate those impulse vibrations into information, such as a direction or location from which the vibrations originate, or a number of those vibrations that are received. The device can adjust its operation in response to the vibrations, such as constructing input data for the device. For example, devices can receive impulse vibrations or other vibrations from one or more locations on a tabletop, and can, in response to a measure of how much the tabletop amplifies or dampens vibrations from those locations, emulate a keyboard, keypad, mouse or trackpad, game controller, musical instrument control, or other input for a computing device.
This application provides techniques, including methods and systems, which can coordinate devices, such as having at least one emitter and at least one sensor, and coupled using one or more radio frequency (RF) or other electromagnetic frequency (EMF) channels. For example, methods and systems as described herein can emit vibrations from a first device and receive vibrations at a second device, the first device sending those vibrations to the second device both using (a) EMF techniques, such as using Bluetooth™ or radiotelephone techniques, near field communication, or otherwise; as well as (b) sonic techniques deliberately mediated by the resonant frequency of one or more objects to which the first and second device are coupled.
In one embodiment, the first and second device can each include a cellular telephone, such as an iPhone™ or other device, wherein the first and second device can be disposed to communicate using EMF techniques, such as a cellular telephone circuit or a packet switched network. In alternative embodiments, the first and second device can each include other devices disposed to communicate using EMF techniques, such as other cellular telephones, an iPad™ or other computing tablet, a netbook, a laptop computer or other portable personal computer, or otherwise. The first and second device can each be disposed on a tabletop, such as a wooden tabletop disposed to support both the first and second device, and disposed to transmit an acoustic signal from the first to the second device. The first device can be disposed to emit one or more such acoustic signals, such as a known frequency for which a frequency response from the tabletop is known to at least either the first or second device, and the second device can be disposed to receive those acoustic signals, such as mediated by that frequency response from the tabletop. The first and second device can be disposed to compare the emitted acoustic signal with the received acoustic signal, in response to which one or both of them can determine an impulse response or a resonant frequency of the tabletop.
While multiple embodiments are disclosed, including variations thereof, still other embodiments of the present disclosure will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the disclosure. As will be realized, the disclosure is capable of modifications in various obvious aspects, all without departing from the spirit and scope of the present disclosure. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a conceptual drawing of a frequency device on a surface.
FIG. 2 shows a conceptual drawing of a first example method of operation.
FIG. 3 shows a conceptual drawing of a second example method of operation.
FIG. 4 shows a conceptual drawing of a two frequency devices cooperating on a surface.
FIG. 5 shows a conceptual drawing of a third example method of operation.
FIG. 6 shows a conceptual drawing of a frequency device.
DETAILED DESCRIPTION
Terminology
The following terminology is exemplary, and not intended to be limiting in any way.
The text “frequency device”, and variants thereof, generally refers to any device capable of generating a sound or other vibration, such as a mobile sound player, mobile telephone, iPhone™, or otherwise. For example, a frequency device can include another type of cellular telephone, an iPod™ or other mobile media player, such as an MP3 player or other music player, an iPad™ or other computing tablet, a netbook, a laptop computer or other portable personal computer, or otherwise. The amount of sound or vibration need not be concentrated in any particular frequency band, and need not be confined to any particular frequency band, such as a human audible frequency band. For some examples, the frequency band can be a human audible frequency band, or another frequency band such as an infrasonic or ultrasonic frequency band. Moreover, the amount of sound or vibration need not be constant, or periodic, or follow any particular pattern.
The text “resonant surface”, “surface”, and variants thereof, generally refers to any surface, or any other portion of an object, whether solid or otherwise, having at least one definable frequency at which that resonant surface has (at least a local) maximum in its response to a frequency applied to that resonant surface. For some examples, a resonant surface can include a relatively flat surface including metal, plastic, wood, or combinations or composites thereof, such as having the effect that a particular frequency is received by the resonant surface and amplified relative to other frequencies. In one such case, a tabletop can have the property that it might reverberate more loudly at 1 KHz than at other frequencies, in which case the 1 KHz frequency would be said to be a resonant frequency of that resonant surface.
After reading this application, those skilled in the art would recognize that these statements of terminology would be applicable to techniques, methods, physical elements, and systems (whether currently known or otherwise), including extensions thereof inferred or inferable by those skilled in the art after reading this application.
Frequency Device on a Surface
FIG. 1 shows a conceptual drawing of a frequency device on a surface.
A frequency device 100 can be disposed on a resonant surface 120 , or can be coupled to one or more objects collectively having at least one such surface 120 .
In one embodiment, the frequency device 100 can include a speaker 102 , disposed to emit one or more acoustic signals. For a first example, the one or more acoustic signals can include an acoustic impulse, such as a click or a pulse, or otherwise disposed to elicit a sonic impulse response from a sonic medium. For a second example, the acoustic signals can include one or more selected frequencies, or combinations or conjunctions thereof, such as one or more pure frequencies, or one or more dual-tone multi-frequency (DTMF) sounds. For a third example, the acoustic signals can include one or more swept-sinusoid signals, or combinations or conjunctions thereof, or other known time-varying signals, such as ramped triangular waves, square waves, or otherwise.
In one embodiment, the frequency device 100 can include a vibration sensor 104 (shown in FIG. 6 ), disposed to receive one or more acoustic signals, such as signals mediated by the surface 120 . For example, the vibration sensor 104 can include an accelerometer, an inertial response sensor, or other device disposed to receive vibrations from the surface 120 .
In one embodiment, the frequency device 100 can include a sonic sensor 106 (shown in FIG. 6 ), disposed to receive one or more acoustic signals, such as those mediated by an ambient atmosphere or other sonic medium. For example, the sonic sensor 106 can include a microphone or other device disposed to receive acoustic signals emitted by the surface 120 .
In one embodiment, the surface 120 can be disposed to have a shape and size, and include one or more materials from which it is manufactured. For a first example, the surface 120 can be made of metal, plastic, wood, or another substance. For a second example, the surface 120 can be laminated or covered with a secondary substance, such as a metal or wooden surface laminated with a plastic covering. The shape and size, and one or more materials, can have the effect that the surface 120 has an acoustic impulse response and one or more resonant frequencies. As described herein, the resonant frequencies of the surface 120 can have the property that an acoustic signal (or portion thereof) having one of those resonant frequencies would be amplified when applied to the surface 120 , and that the amplification would be (at least locally) maximized.
This can have the effect that when the frequency device 100 applies, using the speaker 102 , an acoustic signal including one or more of the resonant frequencies to the surface 120 , the surface 120 would amplify the portion of that acoustic signal including the resonant frequencies, and would provide to the frequency device 100 and returned acoustic signal in which the resonant frequencies would be amplified. This can have the effect that the vibration sensor 104 and the sonic sensor 106 of the frequency device 100 would detect the returned acoustic signal with the portion of the resonant frequencies having been amplified. This can have the effect that the frequency device 100 can detect the resonant frequencies in response to the surface 120 . For example, the frequency device 100 can determine those frequencies at which the surface 120 returns a signal that is maximally amplified.
In one embodiment, the frequency device 100 can include a processor 108 (shown in FIG. 6 ), associated with program and data memory 110 (shown in FIG. 6 ), disposed to interpret instructions in the program and data memory 110 , and disposed to execute those instructions to provide one or more acoustic signals to the surface 120 . For example, the frequency device 100 can be disposed to provide acoustic signals to the surface 120 including one or more impulse vibrations, one or more frequencies, or one or more swept-sinusoids emitted by the frequency device 100 . In such cases, the frequency device 100 can be disposed to provide impulse vibrations as described in any known text describing generation and transmission of impulse signals, emitted as sound. In such cases, the frequency device 100 can be disposed to provide one or more frequencies as described in any known text describing generation and transmission of known frequencies, whether pure or mixed, emitted as sound. In such cases, the frequency device 100 can be disposed to provide one or more swept-sinusoids as described in any known text describing generation and transmission of signals having sine waves of known varying frequencies, emitted as sound.
In one embodiment, the surface 120 can include a relatively flat, relatively solid object, such as a desk or a tabletop. For example, the surface 120 can include one or more regions 122 on which a user (not shown) can poke, scratch, slide, tap, or otherwise cause a vibration or other sonic impulse. This can have the effect that the surface 120 , when the user taps on one such region 122 , emits a sonic impulse that can be received and interpreted by the frequency device 100 .
In one embodiment, the regions 122 into which the surface 120 is divided can indicate specific signals or symbols, such as could be used as a substitute for typewriter keys. In one embodiment, lines or boxes, or typography indicative of those signals or symbols, or other indicators for those signals or symbols, can be projected by the frequency device 100 , or another device, onto the surface 120 . This can have the effect that the regions 122 of the surface 120 can be so divided that the frequency device 100 can detect one of a multiplicity of such signals or symbols. This can have the effect that the surface 120 can be used, in combination with the frequency device 100 , to determine in what region 122 on the surface 120 the sonic impulse occurred. For a first example, the user can tap in one of the corners of the surface 120 , and the frequency device 100 can determine which corner. For a second example, the user can tap in one of a multiplicity of small regions 122 of the surface 120 , and the frequency device 100 can determine which of those small regions 122 . In such cases, the multiplicity of small regions 122 could emulate a keyboard or other form of touchable control element.
In one embodiment, the frequency device 100 may pre-calibrate a set of locations where the user would swipe or tap on the surface 120 . (In one embodiment, the frequency device 100 may detect when the user swipes on the surface 120 , in addition to or in alternative to tapping on the surface 120 .) In one embodiment, the frequency device 100 may pre-calibrate locations by asking the user to swipe or tap at each location in turn. For a first example, the user could swipe or tap at each location in an order requested by the frequency device 100 , or by swiping or tapping at locations using a code to indicate which location, such as Morse code or another known code for representing symbols, or by swiping or tapping at locations using another fixed signal already known to the frequency device 100 . This would have the effect that the frequency device 100 could match the indicated symbol with the acoustic signal associated with that location, thus identifying that symbol with that location. For a second example, the user could swipe or tap at each location with a user-defined identifiable set of touches for each such symbol, with the effect that the frequency device 100 could match the indicated symbol with the user-defined identifiable set of touches and its associated acoustic signal.
In one embodiment, the user may place a printed keyboard, such as made of paper or plastic, under the frequency device 100 . The printed keyboard may indicate a location of where to tap or slide to indicate particular keys or controls. For a first example, a plastic keyboard may include a material with a relatively high resolution of location, by its own impulse response or resonant frequency. For a second example, the locations of keys or controls may be pre-determined by calibration of the frequency device 100 with respect to the surface 120 , such as described above, with the effect that the frequency device 100 would have relatively good resolution of where the user swipes or taps, and without substantial overlap of acoustic signals. For a third example, the printed keyboard may include a set of ridges or other surface features, such that swiping a finger (or other implement, such as a stylus) on or near those surface features would be detectable by the frequency device 100 .
In one embodiment, in cases in which the regions 122 of the surface 120 can be divided into a multiplicity of letters or symbols such as a virtual keyboard, the virtual keyboard can be combined with a display and dynamically adjusted to alter the letters or symbols associated with each key in response to one or more time-varying circumstances. For a first example, the virtual keyboard can be adjusted to use a “SHIFT” key to change the presentation of letters or symbols to indicate upper-case characters instead of lower-case characters. For a second example, the virtual keyboard can be adjusted to show diacritical marks or a secondary set of letters or symbols in response to a function key, such as with a scientific calculator.
While the frequency device 100 and the surface 120 , and associated elements, have been described with respect to one or more particular embodiments, alternative embodiments are possible that remain within the scope and spirit of the invention, would be clear to those of ordinary skill in the art after reading this application, and would not require either further invention or undue experiment.
First Method of Operation
FIG. 2 shows a conceptual drawing of a first method of operation.
A first method 200 includes a set of flow points and method steps. In one embodiment, the method 200 can enable the frequency device 100 to determine one or more resonant frequencies of the surface 120 , and in response to those one or more resonant frequencies, determine information about the surface (such as a shape, size, and composition material of the surface 120 ). In one embodiment, the method 200 can enable the frequency device 100 to use the resonant frequencies of the surface 120 , such as to use the surface 120 as an alarm or noise generator, to use the surface 120 as an amplifier for music or other sound, to find studs, weak points, or other irregularities within the surface 120 , and otherwise.
Although these flow points and method steps are sometimes described as performed in a particular order, in the context of the invention, there is no particular requirement for any such limitation. For example, the flow points and method steps could be performed in a different order, concurrently, in parallel, or otherwise. Similarly, although these flow points and method steps are shown performed by a general purpose processor in a force sensitive device, in the context of the invention, there is no particular requirement for any such limitation. For example, one or more such method steps could be performed by special purpose processor, by another circuit, or be offloaded to other processors or other circuits in other devices, such as by offloading those functions to nearby devices using wireless technology or by offloading those functions to cloud computing functions.
Although these flow points and method steps are sometimes described as performed by the method 200 , they are substantially performed by elements with respect to one or more devices or systems as described herein. For example, one or more such method steps could be performed by the frequency device 100 , by the surface 120 (or by devices coupled thereto), by a portion thereof, by a combination or conjunction thereof, or by other devices or systems as described herein. Moreover, one or more such method steps could be performed by other devices or systems not explicitly described herein, but which would be clear to those of ordinary skill in the art after reading this application, and which would not require either further invention or undue experimentation.
At a flow point 200 a , the method 200 is ready to begin.
At a step 202 , the frequency device 100 can decide whether it will attempt to determine resonant frequencies of the surface 120 , or whether it will attempt to receive an acoustic signal from the surface 120 . If the frequency device 100 decides it will attempt to determine resonant frequencies of the surface 120 , the method 200 proceeds with the flow point 220 . If the frequency device 100 decides it will attempt to receive an acoustic signal from the surface 120 , the method 200 proceeds with the flow point 240 . In alternative embodiments, the frequency device 100 can proceed with both flow points 220 and 240 in parallel.
At the flow point 220 , the frequency device 100 is ready to determine resonant frequencies of the surface 120 . In one embodiment, the frequency device 100 can attempt to determine information about one or more resonant frequencies of the surface 120 by emitting an acoustic signal and receiving a response from the surface 120 .
At a step 222 , the frequency device 100 can emit one or more acoustic signals, such as at the surface 120 . This can have the effect that the acoustic signal is transmitted to the surface 120 . For example, the acoustic signal can include an impulse vibration, one or more selected frequencies, a time-varying signal such as a swept-sinusoid, or otherwise.
For a first example, if the frequency device 100 is positioned near or on top of the surface 120 , and the frequency device 100 includes a speaker 102 , the frequency device 100 can emit a sound that propagates through at least a portion of the surface 120 . For a second example, if the on top of the surface 120 , and the frequency device 100 includes a haptic element such as a vibrating element, the frequency device 100 can emit a vibration impulse that propagates through at least a portion of the surface 120 .
In one embodiment, the frequency device 100 can include a mobile media player, such as an iPod™, iPhone™, or iPad™, or another type of related device, interpreting or executing instructions from an application program.
In one embodiment, the acoustic signal includes a swept-sinusoid. This can have the effect that substantially each frequency within the range of the swept-sinusoid that might be a resonant frequency is presented to the surface 120 as part of an acoustic signal, with the effect that the surface 120 can respond by relatively amplifying the resonant frequency components of that acoustic signal, and relatively damping non-resonant frequency components of that acoustic signal.
In one embodiment, the surface 120 can include a flat surface such as a keyboard (or a flat object painted to look like a keyboard), a table, or some other object. While this application primarily describes surfaces 120 that are substantially flat and have substantially smooth layers, in the context of the invention, there is no particular requirement for any such limitation. For example, one or more such surfaces 120 could be curved, could have ribbed or ridged lines or other texture, or otherwise. As described herein, for example, one or more such surfaces 120 could also include cracks, leaks, studs, or other irregularities, with concomitant effect on the resonant frequencies of such surfaces 120 .
At a step 224 , the surface 120 can receive the acoustic signal. This can have the effect that the surface 120 relatively amplifies the one or more frequencies included in the signal that are resonant frequencies of the surface 120 , and relatively dampens any frequencies that are not resonant frequencies in the signal. For example, if the surface 120 has a resonant frequency of about 1 KHz, the surface 120 provides a response (whether to an impulse vibration, a set of selected frequencies, a swept-sinusoid, or otherwise) in which the resonant frequency is relatively pronounced.
At a step 226 , the frequency device 100 receives, from the surface 120 , one or more responses to the acoustic signal. In one embodiment, the frequency device 100 can analyze the response and determine resonant frequencies of the surface 120 . For a first example, the frequency device 100 can determine each of the resonant frequencies of the surface 120 , or can determine a resonant frequency of the surface 120 with the highest relative amplification. For a second example, the frequency device 100 can determine an impulse response of the surface 120 , either in response to the resonant frequency (or frequencies) of the surface 120 , or in response to a comparison of the emitted acoustic signal with the received acoustic signal.
At a step 228 , the frequency device 100 , in response to a result from the previous step, can determine one or more characteristics of the surface 120 . For example, the frequency device 100 can determine one of: a shape, size, or construction material of the surface 120 , in response to information about the other two of them.
At a step 230 , the frequency device 100 can adjust its operation in response to information about the object. This can have the effect of improving performance of the device in one or more characteristics. For example, should the frequency device 100 determine a resonant frequency of the surface 120 , the frequency device 100 can adjust its operation so that it uses that resonant frequency as a center frequency for sonic output (such as a center frequency for playing music). As described herein, in one embodiment, the frequency device 100 can make other and further adjustments to its operation, with the effect of operating with the surface 120 to greater value.
In one embodiment, the method 200 can continue with step 202 , at which it re-decides whether it will attempt to determine resonant frequencies of the surface 120 , or whether it will attempt to receive an acoustic signal from the surface 120 . In alternative embodiments, the method 200 can continue with the flow point 200 b , at which the method 200 is complete, and can be repeated.
At the flow point 240 , the frequency device 100 is ready to use one or more of the resonant frequencies of the surface 120 .
At a step 242 , the frequency device 100 attempts to use one or more of the resonant frequencies of the surface 120 . As part of this step, the frequency device 100 can attempt one or more of several different uses of the resonant frequencies, as described below:
For a first example, the frequency device 100 can emit an acoustic signal having one or more of the resonant frequencies of the surface 120 as a significant component. In such cases, the surface 120 would respond by amplifying those resonant frequencies. This could have the effect of generating and emitting a relatively loud noise, such as could be used as an alarm.
For a second example, the frequency device 100 can emit an acoustic signal with one of the resonant frequencies as a center frequency for a sound to be amplified, such as music or speech. This could have the effect of generating and emitting an amplified version of the sound. In such cases, the music or speech would be reproduced at a louder volume than the device itself might be able to attain, such as from a loudspeaker.
For a third example, the frequency device 100 can emit an acoustic signal with one of the resonant frequencies as a finder for studs or other irregularities in the surface 120 (such as cracks or leaks), that is, a finder for elements in the surface 120 that differ in density or substance from a remainder of the surface 120 . Such elements could have the effect that the resonant frequencies of the surface 120 would be different at distinct locations near or on the surface 120 . In one embodiment, the frequency device 100 can be moved about until one or more such studs are detected or located.
For example, the detected resonant frequencies of the surface 120 would be different in a “normal” region 122 of the surface 120 , from the detected resonant frequencies would be in a region 122 near or on a stud (or other irregularity, such as a crack or a leak). This could be due to a stud or other irregularity having a different density underneath a top layer of the surface 120 . In one embodiment, the frequency device 100 can emit an acoustic signal including one or more of the resonant frequencies of the surface 120 in the “normal” regions 122 of the surface 120 . Should the frequency device 100 be moved near or on a stud or other irregularity, it could find that those frequencies would not be resonant frequencies near or on such a stud or other irregularity. This could have the effect that the frequency device 100 would be able to detect and locate studs or other irregularities underneath a top layer of the surface 120 .
In one embodiment, the method 200 can continue with the step 202 , at which it re-decides whether it will attempt to determine resonant frequencies of the surface 120 , or whether it will attempt to receive an acoustic signal from the surface 120 . In alternative embodiments, the method 200 can continue with the flow point 200 b , at which the method 200 is complete, and can be repeated.
At a flow point 200 b , the method 200 is complete. In one embodiment, the method 200 is repeated so long as the frequency device 100 is powered on, or if operating under control of an application program, the method 200 is repeated so long as the application program directs it to.
Second Method of Operation
FIG. 3 shows a conceptual drawing of a second method of operation. In one embodiment, the method 300 can enable the frequency device 100 to receive vibration signals from the surface 120 , in response to one or more resonant frequencies of that surface 120 , and determine characteristics about those vibration signals (such as a duration, location, pressure, or otherwise).
A second method 300 includes a set of flow points and method steps. In one embodiment, the method 300 can enable the frequency device 100 to sense acoustic vibrations from an object, such as received from a finger or stylus applied to the object, or from a device applied to the object. In one embodiment, the frequency device 100 can adjust its operation in response to the vibrations, such as constructing input data. For example, the frequency device 100 can receive vibrations from one or more locations on a tabletop, and can, in response to a measure of how much the tabletop amplifies or dampens vibrations from those locations, emulate a keyboard, keypad, mouse or trackpad, game controller, musical instrument control, or other input for a computing device.
Although these flow points and method steps are sometimes described as performed in a particular order, in the context of the invention, there is no particular requirement for any such limitation. For example, the flow points and method steps could be performed in a different order, concurrently, in parallel, or otherwise. Similarly, although these flow points and method steps are shown performed by a general purpose processor in a force sensitive device, in the context of the invention, there is no particular requirement for any such limitation. For example, one or more such method steps could be performed by special purpose processor, by another circuit, or be offloaded to other processors or other circuits in other devices, such as by offloading those functions to nearby devices using wireless technology or by offloading those functions to cloud computing functions.
Although these flow points and method steps are sometimes described as performed by the method 200 , they are substantially performed by elements with respect to one or more devices or systems as described herein. For example, one or more such method steps could be performed by the frequency device 100 , by the surface 120 (or by devices coupled thereto), by a portion thereof, by a combination or conjunction thereof, or by other devices or systems as described herein. Moreover, one or more such method steps could be performed by other devices or systems not explicitly described herein, but which would be clear to those of ordinary skill in the art after reading this application, and which would not require either further invention or undue experiment.
At a flow point 300 a , the method 300 is ready to begin.
At a step 302 , the frequency device 100 can attempt to receive an acoustic signal from the surface 120 .
At a step 304 , the surface 120 receives the acoustic signal. For a first example, the acoustic signal can include an impulse vibration imposed on the surface 120 , such as a finger tap on a location somewhere on the surface 120 . For a second example, the acoustic signal can include a more complex acoustic signal imposed on the surface 120 , such as by a device (such as a pen, stylus, or vibrating element), and can include one or more selected frequencies.
At a step 306 , the surface 120 transforms the acoustic signal in accordance with the impulse response of the surface 120 . For example, the impulse response of the surface 120 can have the property of providing one or more resonant frequencies. As described herein, this can have the effect that the surface 120 relatively amplifies the one or more component frequencies included in the acoustic signal that are resonant frequencies, and relatively dampens any component frequencies included in the acoustic signal that are not resonant frequencies. The one or more resonant frequencies of the surface 120 can have the properties that the frequency device 100 can determine the impulse response of the surface 120 in response thereto.
At a step 308 , the frequency device 100 receives, from the surface 120 , one or more responses to the acoustic signal. For a first example, the surface 120 can send a main response to the acoustic signal, which the frequency device 100 detects. For a second example, the surface 120 can send more than one response to the acoustic signal by means of distinct acoustic paths, which the frequency device 100 can detect. In such cases, sometimes referred to herein as “multipath” cases, the more than one response to the acoustic signal can occur because the acoustic signal is reflected from one or more edges of the surface, or is refracted by one or more portions of the surface 120 .
At a step 310 , the frequency device 100 can analyze the response and determine resonant frequencies of the surface 120 . For a first example, the frequency device 100 can determine each of the resonant frequencies of the surface 120 , or can determine a resonant frequency of the surface 120 with the highest relative amplification. For a second example, the frequency device 100 can determine an impulse response of the surface 120 , either in response to the resonant frequency (or frequencies) of the surface 120 , or in response to a comparison of the emitted acoustic signal with the received acoustic signal.
In one embodiment, the frequency device 100 receives the acoustic signal, and filters it to reduce noise. In one embodiment, having filtered the acoustic signal, the frequency device 100 analyzes a waveform of the received and filtered acoustic signal, and determines an impulse response of the surface 120 in response thereto. In one embodiment, the frequency device 100 , having determined an impulse response of the surface 120 , determines the one or more resonant frequencies of the surface 120 in response thereto.
For a first example, if more than one resonant frequency exists, the frequency device 100 attempts to determine all of them. Should there be multiple resonant frequencies, the resonant frequencies above the base may be a multiple of the fundamental resonant frequency. In one embodiment, if a microphone or other vibration element of the frequency device 100 has only some of those resonant frequencies within its range, the frequency device 100 records only those resonant frequencies within its range.
For a second example, should the frequency device 100 send a time-varying swept-sinusoid acoustic signal to the surface 120 , the surface 120 should provide a response that relatively amplifies the one or more component frequencies included in the acoustic signal that are resonant frequencies, and relatively dampens any component frequencies included in the acoustic signal that are not resonant frequencies. In such cases, the frequency device 100 can determine the one or more resonant frequencies of the surface 120 in response to which component frequencies are relatively amplified and which component frequencies are relatively damped. This can have the effect that, instead of attempting to determine an impulse response for the surface 120 , the frequency device 100 can record which component frequencies are relatively most amplified by the surface 120 .
At a step 312 , the frequency device 100 attempts to determine, in response to the acoustic signal, useful information about the acoustic signal. In one embodiment, the frequency device 100 attempt to determine one or more of the following about the acoustic signal: duration, location, volume, and materials used to induce the acoustic signal.
In one embodiment, the frequency device 100 could maintain a pre-defined database of impulse responses and/or step responses of distinct materials. This could have the effect that the frequency device 100 could determine the nature of the surface 120 (such as its material), or other useful information about the surface 120 (such as its size, shape, and other features) in response to a comparison of the acoustic signal with one or more of those impulse responses and/or step responses. For a first example, the frequency device 100 could have its own vibrational information and location information of its own speaker 102 , vibration sensor 104 , and sonic sensor 106 , as relatively located within the its housing, which the frequency device 100 could take into consideration when comparing the acoustic signal with those impulse responses and/or step responses. For a second example, the user could provide the frequency device 100 with information (such as an estimate) about the size or shape of the surface 120 , such as by using a keyboard or other touch input directly on the frequency device 100 . This could have the effect that the frequency device 100 could take this information into account when analyzing acoustic signals from the surface 120 . For a third example, the user could provide the frequency device 100 with one or more examples of relatively “normal” strength taps on the surface 120 , in contrast with relatively “soft” taps or relatively “hard” taps. This could have the effect that the frequency device 100 could compare relatively “soft” taps or relatively “hard” taps with relatively “normal” strength taps, such as using the vibration sensor 104 and sonic sensor 106 , and could identify a relative wider variety of acoustic signals. For a fourth example, the frequency device 100 could include more than one vibration sensor 104 , more than one sonic sensor 106 , or maintain its vibration sensor 104 and its sonic sensor 106 at a relative distance. This could have the effect that the frequency device 100 could use the separation between multiple sensors to triangulate a location of original of the acoustic signal on the surface 120 .
For a first example, the frequency device 100 can attempt to determine a location from which the acoustic signal originated, such as in response to an amount of relative amplification of one or more resonant frequencies, or an amount of relative damping of one or more non-resonant frequencies. In such cases, the frequency device 100 can attempt to determine a distance the acoustic signal traveled, such as in response to an amount of relative amplification or damping, or in response to a number of multipaths, in response to a time delay as compared with a calibration location, or otherwise. In such cases, the frequency device 100 can attempt to determine a direction the acoustic signal came from, such as in response to a phase delay of the acoustic signal with respect to more than one receiver (such as a stereo receiver), or otherwise. In alternative embodiments, the frequency device 100 can attempt to determine a location from which the acoustic signal originated in response to calibration, by a user tapping at each distinct location to be identified.
For a second example, the frequency device 100 can attempt to determine a duration of the acoustic signal, such as in response to a relative volume of an envelope of the acoustic signal. In such cases, the frequency device 100 could determine that the duration of the acoustic signal includes that time duration when the acoustic signal exceeds a signal to noise threshold, or otherwise.
For a third example, the frequency device 100 can attempt to determine a volume of the acoustic signal, such as in response to a relative volume of an envelope of the acoustic signal. In such cases, the frequency device 100 could determine that the volume of the acoustic signal is responsive to a average peak value of the acoustic signal, or otherwise.
In one embodiment, should the frequency device 100 determine a particular region 122 from which the acoustic signal originated in enough detail, the frequency device 100 can determine a typewriter key, letter, or other symbol as an input from a user. In one embodiment, the frequency device 100 can accept that input for itself, or can direct that input to another device. In alternative embodiments, the frequency device 100 could determine a location to be used as input for a game controller or other device, such as a motion-oriented game.
For example, the frequency device 100 could determine inputs for one or more of the following: (A) The frequency device 100 could determine inputs for a music player, such as one tap to start a song, two taps to pause a song, and otherwise. (B) The frequency device 100 could determine inputs for a game or other application, such as drumming with one or more fingers to indicate inputs to single-player games or multiplayer games. (C) The frequency device 100 could determine inputs for an authentication technique, password, unlock code, or other security measure, such as requiring a user to present a specific drumming or tapping pattern. In one embodiment, the pattern could be specific in location, specific in time, or both, or otherwise.
In one embodiment, the pattern could authenticate a specific user or otherwise indicate that the frequency device 100 should respond to particular commands.
The method 300 continues with the flow point 300 b.
At a flow point 300 b , the method 300 is complete. In one embodiment, the method 300 is repeated so long as the device is powered on.
Cooperating Frequency Devices
FIG. 4 shows a conceptual drawing of a two frequency devices cooperating on a surface.
A first frequency device 100 a and a second frequency device 100 b can be disposed on a surface 120 , or can be coupled to one or more objects collectively having at least one such surface 120 . In one embodiment, each frequency device 100 a and 100 b can include a speaker 102 , a vibration sensor 104 (shown in FIG. 6 ), a sonic sensor 106 (shown in FIG. 6 ), a processor 108 (shown in FIG. 6 ), associated with program and data memory 110 (shown in FIG. 6 ), and otherwise, similar to the frequency device 100 described with respect to the FIG. 1 .
In one embodiment, the surface 120 can be disposed to have a shape and size, and include one or more materials from which it is manufactured, similar to the surface 120 described with respect to the FIG. 1 . The surface 120 can include one or more regions 122 a and 122 b , similar to the regions 122 described with respect to the FIG. 1 .
In one embodiment, the first frequency device 100 a and the second frequency device 100 b can communicate using an electronic communication link 420 , such as a Bluetooth™ communication link, a cellular telephone communication link, a packet switched communication link, or otherwise.
In one embodiment, collectively, the first frequency device 100 a and the second frequency device 100 b can include at least one acoustic emitter and at least one acoustic sensor. This can have the effect that the first frequency device 100 a and the second frequency device 100 b can send acoustic signals from a first location (such as where the first frequency device 100 a is located) and receive acoustic signals at a second location (such as where the second frequency device 100 a is located). In one embodiment, collectively, the first frequency device 100 a and the second frequency device 100 b can include at least one electronic emitter and at least one electronic sensor. This can have the effect that the first frequency device 100 a and the second frequency device 100 b can send electromagnetic signals between the first frequency device 100 a and the second frequency device 100 b.
In one embodiment, the first frequency device 100 a and the second frequency device 100 b can emit acoustic signals from one of the two frequency devices 100 a and 100 b , mediate those acoustic signals using the surface 120 , and can receive those acoustic signals at the other of the two frequency devices 100 a and 100 b . The first frequency device 100 a and the second frequency device 100 b can also send information electronically, such as using the electronic communication link 420 , describing the nature of the acoustic signals that were sent, and comparing them with the nature of the acoustic signals that were received.
In one embodiment, one of the two frequency devices 100 a and 100 b can be disposed to emit an acoustic signal including a selected frequency for which a frequency response from the surface 120 is known to at least one of the two frequency devices 100 a and 100 b . The other of the two frequency devices 100 a and 100 b can be disposed to receive that selected frequency, and compare the sent acoustic signal with the received acoustic signal. Having compared the sent acoustic signal with the received acoustic signal, collectively, the two frequency devices 100 a and 100 b can determine an impulse response or a resonant frequency of the tabletop.
Third Method of Operation
FIG. 5 shows a conceptual drawing of a third method of operation.
A third method 500 includes a set of flow points and method steps.
Although these flow points and method steps are sometimes described as performed in a particular order, in the context of the invention, there is no particular requirement for any such limitation. For example, the flow points and method steps could be performed in a different order, concurrently, in parallel, or otherwise. Similarly, although these flow points and method steps are shown performed by a general purpose processor in a force sensitive device, in the context of the invention, there is no particular requirement for any such limitation. For example, one or more such method steps could be performed by special purpose processor, by another circuit, or be offloaded to other processors or other circuits in other devices, such as by offloading those functions to nearby devices using wireless technology or by offloading those functions to cloud computing functions.
Although these flow points and method steps are sometimes described as performed by the method 200 , they are substantially performed by elements with respect to one or more devices or systems as described herein. For example, one or more such method steps could be performed, either individually or collectively, by the frequency devices 100 a and 100 b , by the surface 120 , by a portion thereof, by a combination or conjunction thereof, or by other devices or systems as described herein. Moreover, one or more such method steps could be performed by other devices or systems not explicitly described herein, but which would be clear to those of ordinary skill in the art after reading this application, and which would not require either further invention or undue experiment.
At a flow point 500 a , the method 500 is ready to begin. The method 500 can coordinate devices, such as having at least one acoustic emitter and at least one acoustic sensor, and coupled using one or more electronic communication links 420 . For example, the devices could include the frequency device 100 a and 100 b , and could communicate acoustic signals mediated by the surface 120 .
At a step 502 , the first frequency device 100 a determines an acoustic signal to send to the second frequency device 100 b . For a first example, the first frequency device 100 a can select an acoustic signal including one or more known frequency components, such as a time-varying swept-sinusoid acoustic signal. For a second example, the first frequency device 100 a can select an acoustic signal including components for which the impulse response or the resonant frequencies of the surface 120 are believed to be known.
At a step 504 , the first frequency device 100 a sends information with respect to the acoustic signal (as determined in the previous step) to the second frequency device 100 b , such as using the electronic link 420 . In alternative embodiments, if the nature of the surface 120 permits, the first frequency device 100 a can send information with respect to the acoustic signal to the second frequency device 100 b using an acoustic signal. For example, the first frequency device 100 a can send a distinct acoustic signal with that information to the second frequency device 100 b , or can encode that information in the same acoustic signal. As part of this step, the second frequency device 100 b receives the information about the acoustic signal.
At a step 506 , the first frequency device 100 a emits an acoustic signal to the surface 120 , the surface 120 propagates the emitted acoustic signal to the second frequency device 100 b , and the second frequency device 100 b receives the propagated acoustic signal. This can have the effect that the emitted acoustic signal is mediated by the surface 120 during transmission from the first frequency device 100 a to the second frequency device 100 b.
At a step 508 , in one embodiment, the second frequency device 100 b can compare the emitted acoustic signal with the received acoustic signal. In alternative embodiments, the second frequency device 100 b sends information with respect to the received acoustic signal to the first frequency device 100 a , which can compare the emitted acoustic signal with the received acoustic signal. Either way, the first frequency device 100 a and the second frequency device 100 b can collectively compare the emitted acoustic signal with the received acoustic signal.
At a step 510 , the first frequency device 100 a and the second frequency device 100 b can collectively determine an impulse response of the surface 120 , or a set of one or more resonant frequencies of the surface 120 . The first frequency device 100 a and the second frequency device 100 b can exchange information so that both have sufficient information to determine that impulse response or those resonant frequencies.
Having determined that impulse response or those resonant frequencies, the first frequency device 100 a and the second frequency device 100 b can proceed similarly to the methods 200 and 300 described with respect to the FIG. 2 and the FIG. 3 .
The method 500 proceeds with the flow point 500 b.
At a flow point 500 b , the method 500 is complete. In one embodiment, the method 500 is repeated so long as the devices are powered on.
Frequency Device Components
FIG. 6 shows a conceptual drawing of a frequency device.
The frequency device 100 can include a processor 108 , and program and data memory 110 including instructions interpretable by the processor 108 to perform methods as described herein, either alone or in combination or conjunction with a one or more additional frequency devices 100 .
The frequency device 100 can include a speaker 102 , a vibration sensor 104 , and a sonic sensor 106 , as described above. The speaker 102 can be disposed to emit acoustic signals, as described above. The vibration sensor 104 can include an accelerometer or other inertial response sensor, and can be disposed to detect vibrations in or on the surface 120 , as described above. The sonic sensor 106 can include a microphone or other sonic-sensitive element, and can be disposed to detect acoustic signals in or on the surface 120 , as described above.
The frequency device 100 can include an input device 112 , such as a keyboard, disposed to allow the user to provide information to the frequency device 100 , as described above. For example, the input device 112 can include a touch-sensitive virtual keyboard presented on a display, such as provided by an iPhone™ or similar device.
The frequency device 100 can include other elements as described herein, and other elements disposed for allowing the frequency device 100 to conduct method steps as described herein. The frequency device 100 can also include other and further elements useful for interaction with the surface 120 , with the user, with acoustic signals (such as emitting or detecting such signals), and otherwise.
Alternative Embodiments
After reading this application, those skilled in the art would recognize that techniques described herein, are responsive to, and transformative of, real-world data such as acoustic and vibrational signals, and resonant frequencies and impulse responses of physical devices, and provides a useful and tangible result in the service of detecting and using resonant frequencies and other information about acoustic and vibrational signals. Moreover, after reading this application, those skilled in the art would recognize that processing of acoustic and vibrational signals by a frequency device includes substantial computer control and programming, involves substantial records of acoustic signals, and involves interaction with acoustic signal hardware and optionally a user interface.
Certain aspects of the embodiments described in the present disclosure may be provided as a computer program product, or software, that may include, for example, a computer-readable storage medium or a non-transitory machine-readable medium having stored thereon instructions, which may be used to program a computer system (or other electronic devices) to perform a process according to the present disclosure. A non-transitory machine-readable medium includes any mechanism for storing information in a form (e.g., software, processing application) readable by a machine (e.g., a computer). The non-transitory machine-readable medium may take the form of, but is not limited to, a magnetic storage medium (e.g., floppy diskette, video cassette, and so on); optical storage medium (e.g., CD-ROM); magneto-optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM and EEPROM); flash memory; and so on.
While the present disclosure has been described with reference to various embodiments, it will be understood that these embodiments are illustrative and that the scope of the disclosure is not limited to them. Many variations, modifications, additions, and improvements are possible. More generally, embodiments in accordance with the present disclosure have been described in the context of particular embodiments. Functionality may be separated or combined in procedures differently in various embodiments of the disclosure or described with different terminology. These and other variations, modifications, additions, and improvements may fall within the scope of the disclosure as defined in the claims that follow. | Devices, using emitted acoustic signals and received vibrations, determine resonant frequencies of a surface or other object, and determine useful information about that surface, including size, thickness, and material. Received vibrations include impulse vibrations from striking that surface with a finger or stylus, or from a frequency or from a swept-sinusoid emitted by the device. The device can adjust its frequency output to use the surface as an amplifier for alarms or speakers, or a center frequency for sonic output. Using an accelerometer, devices sense impulse vibrations, translating those impulses into information, such as keystrokes, game controls, mice, or musical instrument controls. Devices can emulate keyboards and input devices using tabletops. Devices can coordinate signals through multiple media, including air, surface, or EMF channels. | 6 |
BACKGROUND OF INVENTION
This invention relates generally to ground fault measurement. More particularly, this invention relates to an algorithm to prevent nuisance tripping due to inaccurate ground fault current calculation.
Ground faults are the result of currents flowing through a ground return path. In electrical systems, current should flow from one of the power phases out to the electrical load and return on another power phase or the neutral circuit. The detection of ground fault currents is a common protective mode for high function circuit breakers. The manner that this protection is accomplished varies, but a common approach is to calculate the ground fault current by summing the values of phase and neutral, if in use, currents. In normal, unfaulted use, this signal is zero. If a signal exists, it indicates that some of the current is returning via a ground path. Then, this measured ground fault current is compared to an operator-selected threshold to determine if the circuit breaker should trip.
High level fault currents provide one common source of inaccuracy in a ground fault measurement. When high fault or temporary application currents (for example, motor starting) flow, the small errors due to tolerance or sensor saturation can become relatively large when compared to the ground fault signals that a trip unit attempts to detect. Due to the short trip times customary in ground fault protection, these errors can cause false or nuisance tripping.
A nuisance trip in a circuit breaker can cause expensive processes to shut down. It can have serious ramifications and be very costly. Ground fault protection can be a source of nuisance tripping if the method for determining the ground fault current is, under certain conditions, sufficiently inaccurate.
Inaccurate ground fault current calculations occur when the threshold for ground fault protection is very small compared to the measured phase currents. If the phase currents are sufficiently large and the ground fault threshold is sufficiently small, the error in measuring ground fault current can result in a level that can exceed the specified trip level for a ground fault circuit.
One method used to deal with the inaccuracy noted above is to make the measurement of the phase currents so accurate that the calculated ground fault current is sufficiently accurate. This is difficult and expensive to do especially when large phase currents are used to calculate small ground fault currents. Another method involves eliminating or disabling the ground fault function when fault currents exceed a specified level. This avoids the nuisance tripping but may allow incremental damage in the faulted circuit (due to a longer tripping time), particularly if the high level fault is entirely a ground fault.
SUMMARY OF INVENTION
The above discussed and other drawbacks and deficiencies of the prior art are overcome or alleviated by a method for ground fault circuit interruption. In an exemplary embodiment of the invention the method includes determining a minimum ground fault setting for detected phase currents, comparing the minimum ground fault setting to a customer provided threshold, determining a maximum value between the minimum ground fault setting and the customer provided threshold, and, utilizing the maximum value as a ground fault threshold.
In another exemplary embodiment of the invention, a storage medium encoded with machine-readable computer program code for determining a ground fault threshold, may include instructions for causing a circuit breaker microprocessor to implement the above-described method.
In another exemplary embodiment of the invention, a trip unit may include phase protection circuits, a ground fault protection circuit, and, a phase current qualification circuit intermediate the phase protection circuits and the ground fault protection circuit, wherein the phase current qualification circuit includes circuitry for determining a minimum ground fault setting for detected phase currents.
In another exemplary embodiment of the invention, a circuit breaker containing a plurality of phases and sets of contacts may include the above-described trip unit.
The above-discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.
BRIEF DESCRIPTION OF DRAWINGS
Referring to the exemplary drawings wherein like elements are numbered alike in the several FIGURES:
FIG. 1 is a diagrammatic representation of a circuit breaker having ground fault protection; and
FIG. 2 is a diagrammatic representation of a circuit breaker having ground fault protection with phase current qualification.
DETAILED DESCRIPTION
The algorithm of this invention may be implemented in a program that controls the circuit breaker electronic trip unit. The algorithm determines when conditions are such that inaccurate results would occur with calculated ground fault currents. The algorithm then adjusts the tripping threshold higher, and by doing so prevents nuisance tripping.
Referring to FIG. 1, a block diagram of a circuit breaker 10 having a ground fault measurement algorithm is shown. Many elements of an actual circuit breaker are not shown for clarity, and the emphasis for the purpose of describing this invention lies in depicting relative features of the trip unit. Phases A, B, and C (lines 12 , 14 , and 16 ) flow through the circuit breaker 10 and a set of current transformers 20 , 22 , 24 detect current of each respective line 12 , 14 , and 16 . The neutral path N 18 , which is typically connected to ground at the source and normally not interrupted by the circuit breaker 10 provides a return path for unbalances in current in a 3 phase system. For ground fault protection, a current transformer 26 must sense the neutral current as well. The outputs of the current transformers 20 , 22 , 24 , and 26 are processed via the phase amplifiers 34 , 36 , 38 , and 40 and provided to the phase protection circuits 30 for overcurrent protection (long time, short time, and instantaneous). These signals are provided to the ground fault circuit 32 as well. The 3 phase signals and neutral are added together (including the polarity of all 4 signals) in the summing amplifier 42 . In some alternative implementations, the summing may be performed by a small secondary current transformer. In an electrical system with no ground fault (that is, no inadvertent connection to ground on the load side 28 of the circuit breaker 10 ), the currents which flow out on any given phase must return to the electrical source via another phase or the neutral. In this case, the sum of the phase currents and neutral must equal zero. If they do not equal zero, the summing amplifier 42 will have an output equal to the difference from zero. In an errorless system, this signal will correspond to the amount of current which flows in the ground fault. The customer can set a level of ground fault above which the tripping algorithm starts (pickup) using a customer adjustable threshold mechanism 44 . Although any mechanism for entering the customer adjustable threshold is within the scope of this invention, an exemplary mechanism would include a rotary switch, keypad, or any multiposition switch with switch positions corresponding to settings. The customer adjustable threshold and the residual current are compared in a comparator 46 for determining the ground fault pickup. The signal from the summing amplifier 42 is passed to an integrator 48 and the circuit 32 will generate a trip signal 50 at a time delay which is fixed or proportional to the amount by which the square of the ground fault current exceeds the customer selected threshold.
The trip signal 50 is then passed to a line 52 which may lead to a trip actuator 54 and operating mechanism 56 for opening the contacts 58 , 60 , and 62 which interrupt the flow of current from the lines 12 , 14 , 16 to the load 28 . The line 52 may further include a microprocessor for receiving the trip signal 52 and setting the trip actuator 54 into motion, such as by the use of a solenoid or other known means of creating a trip action, all of which would be within the scope of this invention.
The ground fault thresholds in industrial circuit breakers can be set typically from 20% to 60% of the circuit breaker capacity. When phase currents are less than 100% of the capacity, small errors in measurement, 2 to 3%, do not affect the ground fault protection. When phase currents reach 300% or 500% of breaker capacity, the same 2% or 3% error, becomes a signal equivalent to 20% of the breaker capacity as the current transformers 20 , 22 , 24 often perform poorly at higher currents. In this case, a balanced, fault level current may create a false unbalance which causes the ground fault circuit 32 to pickup and operate. If the high phase current is the result of a normal load such as the inrush current of a high efficiency motor, the circuit breaker 10 may erroneously trip when no fault is present.
To avoid this problem, some trip units disable ground fault whenever high fault currents are present. This provides very poor protection when a “hard” ground fault occurs such as a short circuit of a phase directly or indirectly to ground. Due to the poor ground path, the fault may be limited to 300% or 500% of breaker capacity. The normal phase protection circuits 30 will interrupt this fault, but the fault may persist for 10 seconds or more. Equipment damage can occur at these high levels for this delay. The improved circuit breaker and algorithm of this invention avoids both of these problems.
As the exact algorithm will differ by hardware platform tolerances and performance, the procedure for determining the algorithm is preferably as follows:
characterize the expected errors in phase current measurement which are not correlated: some errors such as A/D reference error will affect all phase measurements identically; also, current transformer error may be characteristic of an expected error, that is, while the absolute error is +/−3%, the variation in error at a specific point is small, so the error from several current transformers measuring similar currents may cancel somewhat; amplifier offset and resistor tolerance in gain circuits are other exemplary sources of error.
determine the phase current level or levels at which erroneous readings may occur
override the customer threshold level to raise the ground fault pickup above the phase current error level whenever any of the phase current measurements exceed the determined levels.
For example, if the phase current measurement has 6% error at 300% of breaker rating, this equates to a ground fault error of 18%, almost equal to a minimum threshold of 20%. When the processor calculating phase current senses this level, the customer threshold may be overridden if it is 20%. The trip unit processor, i.e., the phase current qualification block in FIG. 2, may raise the threshold to 30%. Note in this example, if the phase current of 300% is all ground fault, the ground fault circuit will still detect a ground fault condition (300%>>30%) and trip the circuit breaker quickly. It is important to note that the ground fault protection is not disabled altogether but simply made less sensitive.
FIG. 2 shows the modifications to the trip unit of the circuit breaker 100 , in block diagram form. A microprocessor 102 (which encompass the entire phase current qualification circuit, the ground fault circuit, and the phase protection circuits) which must measure the phase currents for phase protection compares the current level with stored values which have high errors. The circuit breaker 100 includes a phase current qualification circuit 104 which receives phase current information from the phase protection circuits 30 and determines the maximum phase current being received by the circuit breaker 100 within the maximum phase current selector 106 . The phase current qualification circuit 104 includes storage 108 , such as a read only memory or a fixed analog circuit, for storing phase current error levels, that is, values which have been known to have high errors. Both the maximum phase current information and the stored phase current error levels are sent to a summer 110 . Depending on the level of the maximum phase current, a minimum ground fault threshold 112 is selected from processor memory 108 (preferably determined offline). Both the customer adjustable threshold 44 and the minimum ground fault threshold 112 are entered into a maximum ground fault threshold selector 114 . Thus, the ground fault threshold becomes the maximum of the customer setting and the minimum value that varies with fault current. The remainder of the ground fault circuitry preferably remains the same, that is, the signal from the summing amplifier 42 is passed to an integrator 48 and the circuit 32 will generate a trip signal 50 at a time delay which is fixed or proportional to the amount by which the ground fault current exceeds the customer selected threshold or the minimum ground fault setting, whichever is greater. The trip signal 50 will initiate a trip response to separate the contacts 58 , 60 , and 62 as previously described.
Note that while this disclosure discusses independent phase and neutral measurements summed electronically and the protection algorithm implemented by a processor, those skilled in the art could, in light of this invention, employ summing transformers and analog circuitry to achieve the same end.
Additionally, at least in part, the electronic trip unit of the circuit breaker of the present invention can be embodied in the form of computer-implemented processes and apparatuses for practicing those processes. The present invention can, in part, also be embodied in the form of computer program code containing instructions embodied in tangible media, such as floppy diskettes, CD-ROM's, hard drives, or any other computer-readable storage medium, wherein, when the computer program code is loaded into and executed by a computer or circuit breaker microprocessor, the computer or circuit breaker microprocessor becomes an apparatus for practicing the invention. The present invention can also be embodied in the form of computer program code, for example, whether stored in a storage medium, loaded into and/or executed by a computer or circuit breaker microprocessor, or transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via electromagnetic radiation, wherein, when the computer program code is loaded into and executed by a computer or circuit breaker microprocessor, the computer or circuit breaker microprocessor becomes an apparatus for practicing the invention. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. | A method for ground fault circuit interruption is disclosed in which the method includes determining a minimum ground fault setting for detected phase currents, comparing the minimum ground fault setting to a customer provided threshold, determining a maximum value between the minimum ground fault setting and the customer provided threshold, and, utilizing the maximum value as a ground fault threshold. A storage medium encoded with machine-readable computer program code for determining a ground fault threshold may include instructions for causing a circuit breaker microprocessor to implement the method. A trip unit and a circuit breaker including the trip unit are also disclosed which may include phase protection circuits, a ground fault protection circuit, and, a phase current qualification circuit intermediate the phase protection circuits and the ground fault protection circuit, wherein the phase current qualification circuit includes circuitry for determining a minimum ground fault setting for detected phase currents. | 7 |
STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
BACKGROUND OF THE INVENTION
Towed seismic streamers containing a hydrophone array have been in use for some time as data gatherers. The information obtained has been of particular interest for oil exploration, and other marine geophysical studies, to name a few. Typical examples of the evolving state-of-the-art are shown in U.S. Pat. No. 2,465,696 to Leroy C. Paslay for his Method and Means of Surveying Geological Formations; the Pressure Cable Construction of F. G. Blake et al in U.S. Pat. No. 2,791,757; the Method and Underwater Streamer Apparatus for Improving the Fidelity of Recorded Seismic Signals of G. M. Pavey, Jr. et al in U.S. Pat. No. 3,290,645 as well as Pavey's later apparatus of U.S. Pat. No. 3,319,734; Frank R. Abbott's Towable Sonar Array With Depth Compensation of U.S. Pat. No. 3,868,623 and J. J. Babbs Shallow Water Seismic Prospecting Cable of U.S. Pat. No. 3,435,410. These patents show typical examples of the efforts undertaken to upgrade the validity of the data obtained by using improved transducers, data processing techniques and general design considerations. All these designs represent advances in the state-of-the-art; however, it is safe to say that all would seek to improve the validity of the collected data to one degree or another.
One aspect of design allowing the quality of the gathered data to be improved is the provision of a device for blocking mechanical shocks and vibrations originating in other structural members from reaching the array. The streamlined outer surface presented by a hose-like sheath in most of the patents cited above represents an attempt to avoid some of the motional disturbances to the acoustic sensors. Yet, high speed towing creates unwanted shock and vibration due to unsteady motion of the towing platform, vibration of the propulsion machinery, strumming of the tow cable, and unstable motion of the drogue used to tension the array. These many mechanical disturbances, if allowed to propagate to the acoustic sections of the array, cause accelerations and pressure fluctuations within the array that are monitored and converted into erroneous signals by the receiving transducers.
An attempt to reduce the motional disturbances has been the inclusion of vibration isolation modules. Currently, the modules typically consist of an outer plastic hose, a fill fluid, an internal compliant member or members (usually in the form of a nylon rope), an internal slack essentially nonextensional member or members (usually in the form of a steel cable or a rope made of very strong, stiff aramid fiber such as that marketed under the DuPont Company trademark KEVLAR), appropriate very slack electrical conductors, and suitable end caps. At very low speeds the load of the vibration isolation module and its towed array is carried by the hose wall alone. When somewhat higher speeds are reached, the load is carried by the hose wall and the internal compliant member jointly. Within these lower speed regimes the vibration isolation module functions primarily as a spring with some damping resulting from tensional losses in both the hose wall and the compliant member and from viscous flow in the fill fluid.
Traveling at some still higher speed the hose wall and compliant member "bottom out" when the essentially nonextensional member becomes taut. At this point all vibration and shock isolation is lost and the array is subject to accelerated wear and early failure.
Thus there is a continuing need in the state-of-the-art for a vibration isolation module that provides for greater damping and higher dynamic range without "bottoming out" or being permanently stretched, and which also more effectively reduces the influences of longitudinal shock and other longitudinal motional disturbances from compromising the response of the towed acoustic array. Such a device would also find applications where such shocks and disturbances were to be isolated from members attached to opposite ends of the modules such as in a restraint harness, between a towed barge and a tug or in an instrumentation package suspended from shipboard or a buoy.
SUMMARY OF THE INVENTION
The present invention is directed to providing an apparatus for providing longitudinal shock mitigation and reducing the influences of longitudinal motional disturbances between members coupled to its opposite ends while permitting desired communication between these opposite ends whether by electrical conductors, optical fibers, or tubes. A cylindrically-shaped elongated core is coupled between the members for compliantly and dissipatively yielding and at least one cord-like or ribbon-like essentially nonextensible high-strength member is disposed about the core in a helical fashion having at least one symmetrically-located pitch reversal. Note: What is meant here and elsewhere with reference to the high strength member or members by the terms "essentially nonextensible" is that the product of the cross-sectional area of the strength member and its Young's modulus is very high in comparison with that of the core. Thus, the cord-like member has the property of being relatively nonextensible as compared to the core. This high-strength member is attached to the core at least at the point of pitch reversal and to the end members for imparting torsional strains to the compliantly and dissipatively yielding core, which strains are non-linearly related to the steady strain and the longitudinal shock and motional disturbances. A hose-like sheath is disposed to contain both these members as well as a viscous fill fluid. The sheath further provides for additional shock and motional disturbance reduction as the apparatus is longitudinally stretched. A plurality of the cord-like or ribbon-like high-strength essentially nonextensible members can be provided, each having one or more pitch reversals so long as the helical angles and directions for all the non-extensible members are the same, the pitch reversals occur at common stations along the core, and the nonextensible members are attached to the end members and to the core at least where the common pitch reversals occur. The tensile reaction for small extensions is dominated by the initial pitch of the cord-like torsion producing member and the elastic properties of the core. The tensile reaction for large extensions are dominated by the elastic properties of the cord-like torsion producing members, themselves, allowing appropriate selection of the initial and final slopes of the tension vs. elongation curve and the location of the knee therein. Thusly configured, the acoustic performance of an array is improved. Other applications of the module are to improve the towing characteristics of a barge being towed by a tug or other vessel, the securing of an occupant in a seat by a harness arrangement joined to an appropriately modified module, motion reduction of instrumentation packages suspended from a ship or buoy and other applications where shocks and disturbances are to be isolated.
It is a prime object of the invention to provide an apparatus for mitigating longitudinal shocks and the influences of longitudinal motional disturbances while permitting the communication of power and intelligence between its opposite ends.
Another object of the invention is to provide a shock and disturbance reducer having a nonlinear, longitudinal stress/strain characteristic with a desirable dissipation capability.
Yet another object of the invention is to provide a shock and disturbance reducer which transforms longitudinal stresses to torsional strains.
A further object of the invention is to provide an essentially cylindrically shaped core of elastomer having at least one cord-like or ribbon-like essentially nonextensible strength member wrapped about in a helical configuration having at least one symmetrically disposed pitch reversal for translating longitudinal stresses to torsional strains.
Yet still another object is to provide a vibration isolation module having a nonlinear torsional strain converting section for reducing the effects of shock and severe longitudinal motional disturbances.
Still another object of the invention is to provide a vibration isolation module having a nonlinear torsional strain dissipative member cooperating with a coaxially disposed longitudinal strain converting member for sharing the stresses imposed by longitudinal shocks and longitudinal motional disturbances.
Still another object of the invention is to provide a torsional strain dissipative member, a coaxially disposed longitudinal strain producing member having an interposed viscous fluid that provides, through shear losses, an additive reduction of longitudinal shock and motional disturbances.
Still another object is to provide a vibration isolation module that utilizes a lossy elastomeric core in which longitudinal stretching of the module is converted into both longitudinal stretching and torsional shear of the core.
Another object is to provide a vibration isolation module that converts longitudinal stresses into torsional motion to greatly increase the shear losses and its motion relative to a fill fluid to greatly increase the viscous damping thereof between a core and a jacket.
Yet another object is to provide a vibration isolation module producing a longitudinal stress to torsional shear conversion that is nonlinear with a conversion ratio such that the effective spring constant of the module increases with increasing steady tension that correlates to increasing tow speed.
Still another object is to provide a vibration isolation module having a spring constant which increases with tension to support a much greater drag at higher tow speeds without undue stretching or "bottoming out".
Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sketch depicting at least one vibration isolation module interposed between an acoustic array and a towing cable from a ship.
FIG. 2 is a vibration isolation module partially in cross-section that shows one pitch reversal of an essentially nonextensible cord located outside the elastomeric core and secured onto the core by a clamp where the pitch reversal occurs. (For simplicity, no additional means for conveying intelligence or power is shown).
FIG. 2a is a cross-sectional end view of the embodiment of FIG. 2 shown generally along lines 2a--2a in FIG. 2.
FIG. 3 is a vibration isolation module depicted partially in cross-section having two essentially nonextensible strength members and two pitch reversal sites with the strength members being secured by clamps at least at the pitch reversal points. Also included is an annular spacer at a node midway between the two pitch reversals, which assists in mode conversion and transfers load in the hosewall to the core.
FIG. 3a is a cross-sectional representation of the embodiment of FIG. 3 shown generally along lines 3a--3a in FIG. 3.
FIG. 4 is another embodiment of a vibration isolation module having three (or more) nonextensible cords each disposed in a separate helical groove provided in the compliant core with annular spacers disposed at the nodes located midway between consecutive pitch reversals.
FIG. 4a is a cross-sectional representation of the embodiment of FIG. 4 shown generally along lines 4a--4a in FIG. 4.
FIG. 4b is a cross-sectional view of the embodiment of FIG. 4 shown along lines 4b--4b in FIG. 4a depicting one end cap and the nonextensible cord interconnection of the embodiment of FIG. 4. Although the termination of each cord in the end cap is shown only schematically in the figure, a wide variety of in-line terminations is available, ranging from swaged sleeves and ferrules to wedging plug and socket combinations.
FIGS. 5a-5c present diagrams and equations relating the various variables including the rotation of the core at the pitch reversal point as a function of longitudinal strain and the initial helix angle of the nonextensible cord-like member on the compliant core.
FIG. 6 is a graph showing the relation between the longitudinal strain and the fractional unwinding (torsional twisting) that takes place in the core as the nonextensible cord-like members straighten. (B=0 corresponds to the initial unstrained condition, and B=1 corresponds to the extension at which the cord-like members have become straight and taut. The individual curves are for the indicated initial helical angles, θ.)
FIG. 7a displays the permissible operating region for the most desired type of operation, as a function of the design parameter, W, and the longitudinal strain, s. For values of W below the zero response floor, no rotation of the core occurs with stretching because the circumference of the core falls fast enough, due to Poisson's ratio, to accomodate the change in helix angle. Beyond the taut limit, any additional stretching can occur only with stretching of the cords.
FIG. 7b is a graph showing the tension versus the longitudinal strain of a typical core for various values of the parameter W for the case in which the axial stiffness of the cords is extremely high. The marked up-bending of the curves displays the severe nonlinearity thereof.
FIG. 7c presents data on a core in which the compliance of the core material is less and that of the cords is considerably greater than for the cores of FIG. 7b. The increase in dynamic range can be noted by comparing the ordinate ranges for the two figures.
FIG. 8 is a vibration isolation module interposed in shortened hawsers coupled to a barge and a towing vessel.
FIG. 9 shows a vibration module adapted to provide shock mitigation for an instrumentation package suspended from a floating platform or buoy.
FIG. 10 is a representative depiction of a vibration isolation module adapted to a seatbelt or harness arresting structure.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and in particular to FIG. 1, a vibration isolation module 10 is coupled between an acoustic array 11 and a towing cable 12 pulled through the water by a support vessel 13. At the tail end of the array, another vibration isolation module 10' provides isolation between the array and the rope or other drogue 12A used to tension the array. Although the towing vessel is shown as a surface craft, many of the adverse influences on a towed hose-like transducer array are eliminated when a submersible is used as the towing vessel. Also, although not shown in the figure, if one or more separate arrays are added, additional modules can be interposed to isolate one array from another.
The many very sensitive transducer elements disposed along the array's length, in addition to being responsive to the signals of interest, are also responsive to the longitudinal disturbances and the pressure waves created by them. These unwanted disturbances tend to hide the signals of interest and also often produce highly misleading data. These deleterious motional disturbances can be attributed to machinery vibrations, to the roll, pitch, heave and yaw of the towing platform, to strumming of the towing cable, and to the unsteady motion of the drogue, all of these effects becoming more severe as higher towing speeds are reached. Vibration isolation module 10 (and 10') forming the subject matter of invention reduces the effects of the longitudinal motional disturbances, and the destructive effects accompanying longitudinal shocks when conventional vibration isolation modules "bottom out".
Looking to FIGS. 2 through 4 where like reference characters depict like or substantially similar elements, vibration isolation module 10 includes as the principal longitudinal load-bearing members a core assembly, consisting of items 15, 25, and 26 and 18, and 31, if used, and coaxially disposed jacket 20. The core 15 of the core assembly is essentially a lossy elastomeric material which is selected to translate longitudinal stresses into torsional shear strains in a manner to be elaborated on below. The conversion of tensile strain to mechanically amplified torsional shear has been found to provide greatly increased dissipation, and the nonlinear conversion mechanism used allows equal incremental increases in shear stress to balance disproportionately larger and larger tensile forces. This bestows on the mechanism a nonlinear spring constant, and allows the vibration isolation module to accommodate the much greater drag produced by longer arrays and higher towing speeds, without unduly stretching or "bottoming out".
The elastomeric material selected for the core possesses a usefully high loss tangent, low tensile and shear modului, a high permissible elongation, a low tensile set and a good resistance to the aliphatic hydrocarbon or other fill fluid 23 disposed in the annular space formed between the core and the jacket. One highly suitable core material now appears to be an ethylene/acrylic elastomer marketed by DuPont under the tradename "VAMAC". This material has a loss tangent of 0.24 to 0.32 at typical ocean temperatures. An approximately one inch diameter core of "VAMAC" of various lengths has been found to provide the desired descriptive properties for the anticipated towed array application. Other elastomers, such as butyl rubber, are also useful in those applications in which any swelling effect caused by the fill fluid can be avoided.
The material for the jacket of the vibration isolation module is selected to provide some longitudinal load sharing between the core assembly and jacket over the operating speed range of the towed array. Selecting a commercially available properly dimensioned sheath or jacket material fabricated from either an ether-base polyurethane or from a polyvinyl chloride material having low-temperature flexibility and an ultra-violet inhibitor has been found to be suitable for a variety of array lengths and speeds.
The ultimate longitudinal stretch of the vibration isolation module, including the core and sheath, is limited by one or more essentially nonextensible cord-like members 25. The cord-like members can have a circular cross-sectional shape like a true cord or have a flattened appearance like a ribbon. In either case they function to transmit forces and loads. The embodiment of FIG. 2 and 2a shows a single cord-like member 25 helically extending along the length of the compliant core and having a single pitch reversal 21 and a pitch reversal clamp 26 at the mid-length point of the core. The embodiment of FIG. 3 shows a pair of cooperating but diametrically opposed, essentially nonextensible cord-like members 25' and 25" wrapped with equal pitch about the compliant core 15 having a pair of pitch reversals 21' and 21" at pitch reversal clamps 26' and 26", with the pitch reversal points being located at the one-quarter and three-quarter length positions. The embodiment of FIG. 4 shows three essentially nonextensible cord-like members 25'" being symmetrically disposed about the center of the core, having identical pitch and having several common uniformly spaced pitch reversal points. In any embodiment or further modifications not specifically described, one or more essentially nonextensible cord-like or ribbon-like members determines the ultimate stretch of the module that is capable of producing torsional shear in the core. Here it should be pointed out again, that the term "essentially nonextensible" is used to mean that the ratio of the tensile stiffness of the cords or ribbons to that of the core is large or very large, and that, by reason of the nonlinear relation between tension in the cords and the torsional reaction, this ultimate longitudinal stretch is beyond the best operating point for the system.
Referring back to FIG. 2, each end of the essentially nonextensible cord-like member is secured to a fitting or end cap 27 to transmit the steady component of the tension and to assure that responsive longitudinal motional disturbance is longitudinally reduced as well as torsionally dissipated. The fitting or caps are provided with pad eyes for connection to the towing cable 12 and array 11. Pad eyes, as such, are shown for demonstration purposes only. Obviously, many different types of presently available mechanical connections would serve this purpose. The connections preferably are streamlined or contained in streamlined housings 28 to avoid turbulance caused by hydrodynamic flow. Jacket 20 is bonded to the end caps using suitable adhesives and sometimes constricting metal straps or high-strength wrappings 27a and 28a are suitably applied to hold the jacket more securely on the caps. The straps or wrappings also are configured to reduce the problems associated with hydrodynamic flow.
In the FIG. 2 embodiment, pitch reversal clamp 26 secures the essentially nonextensible member 25 to a point 30 of helical pitch reversal of the essentially nonextensible member on elastomeric core 15. The opposite ends 25a and 25b of the cord-like member are secured to end caps 27 and 28. Ends 25a and 25b are shown as having been passed through holes in the end caps and then secured with knots. Other stronger securing means could be, and usually are, employed. For example, the knots could have been replaced or augmented with swaged or crimped ferrules or the ends could have been unwraveled and potted in plastic or socket-and-plug in-line terminations could have been used. With the arrangement shown in FIG. 2, the opposite ends 15a and 15b of the core are bonded or otherwise suitably secured in end caps 27 and 28. The single essentially nonextensible cord, having a single pitch reversal at the pitch reversal clamp, causes the varying longitudinal motion between the two end caps to create torsional forces that twist the core in torsional shear about its longitudinal axis when shocks or longitudinal motional disturbances are transmitted to the vibration isolation module via end cap 28 from towing cable 12. In other words, the longitudinal stresses created by the shocks and motional disturbances are translated into torsional shear strains within the compliant core member. These strains are in addition to the longitudinal strain borne by the compliant core which is shared by the jacket that is secured onto both of the end cap members. Furthermore, the viscous fluid in between the jacket and core provides additional attenuation of the varying longitudinal stresses through viscous shear dissipation.
Referring to FIG. 3, another embodiment has two essentially nonextensible cord-like members 25' and 25" which helically extend about the elastomeric cord. The two cord-like members which are diametrically opposed have the same pitch and direction and are attached by pitch reversal clamps 26' and 26" onto the elastomeric core at the one-quarter and three-quarter length points. The two pitch reversal clamps are each coupled to both of the essentially nonextensible cord-like members 25' and 25" and impart a translation of any longitudinal extension of the assembly into oppositely directed torsional rotations. These torsional rotations act on the core at the pitch reversal points which produce torsional shear strains within the section of the elastomeric core between the two points of pitch reversal and also between each end of the core and the adjacent pitch reversal point. Approximately midway between the successive pitch reversals, a node 30 is created in which there is substantially no rotational motion of the elastomeric core. An annular spacer 31 made up of joinable segments and disposed radially outwardly of the core and between the sheath and the core is mounted at the node to snuggly fit between the jacket and core to aid in mode conversion and to transfer drag load on the covering sheath or hosewall to the core. At least one opening 31a is provided in each of the annular spacers where the pieces join to allow the passage of the electrical, optical or other conductors 34 of the array. No conductors are shown in the embodiments of FIG. 2 and 3; however, the conductors are shown in the embodiment of FIG. 4. These flexible conductors are either wrapped loosely about the assembled core, roughly matching the pitch and direction of the cords or they are laid in a serpentine pattern between the core and outer jacket. In either case their length must safely exceed the maximum expected stretched out length of the module.
The essentially nonextensible cord-like members impart dissipative torsional strains to the core when the longitudinal shocks and motional disturbances would otherwise be transmitted to the array. The most nonextensible members were fabricated from a number of strands of an aramid fiber marketed under the registered trademark KEVLAR by E. I. DuPont. Strands fabricated from these fibers have superior tensile strength characteristics without excessive strain over the stress range of interest, and low-angle braided cord made from eight strands of the fibers covered by a woven polyester covering have proven to work in a highly satisfactory manner for translating the longitudinal stresses to torsional strains within the compliant core. Twisted and single- and double-braided cords made of other plastic fibers such as polyester, polyolefin, polypropylene and nylon have been used to achieve lower changes in the effective overall spring constant of the assembly with increasing extension, which in turn, makes the non-linear effect less severe.
Looking once again to FIG. 2, the essentially nonextensible cord-like member 25 is located on the outer surface of the compliant core in its helically extending, pitch reversing orientation. It is secured to the core at its pitch reversal clamp 26 as well as where it extends through each of the end caps and terminates in knots 25a and 25b. Optionally, it is bonded or otherwise suitably affixed along a contiguous surface where it abuts the outer surface of the elastomeric core. The embodiment of FIG. 3 having the two cord-like members 25' and 25" also could be bonded or adhered along their length to the outer surface of the compliant core as well as being secured to the pitch reversal clamps 26' and 26". Connection of the two members to the end cap could be similar to that shown with respect to FIG. 2 or as previously described. As mentioned above, when the core and cord are attached to the endcaps and are elsewhere free to rotate, the maximum rotation occurs at the pitch reversal points, and none occurs at the nodal points midway between these pitch reversals. The spacing and placement of the pitch reversal points are chosen so that the end caps also are positioned at nodal or non-rotation points. Note node 30' in FIG. 3 here, the node or non-rotating point lies halfway between the pitch reversal clamps 26' and 26". The reader will also note that the continuity breaks along the length of the module have been used in the figures to permit showing of essential structure without undue redundancy of structure in the illustration.
The embodiment of FIG. 4 has a modified compliant core member 15' that is provided with three helically extending grooves 16 provided in its outer surface layer. The grooves are cut into the core and have pitch reversals at locations generally designated by the reference character 17 where the grooves undergo a pitch reversal. Within each of the grooves a multiple strand cord-like member 25'" is disposed, it being understood that the depth of the groove is configured to receive a portion or all of a cord-like member within it. The pitch reversal clamps required on the embodiments of FIGS. 2 and 3 are not needed, but elastic retainer rings 18 hold the cord-like members within the grooves and assure the structural integrity of the module. They are spaced such that they do not interfere with annular spacers 31 provided at selected nodes 30" wherever they occur along the length of the module. An alternate construction technique that dispences with the requirement for retainer rings is to bond or embed the cords in place in the grooves with a flexible adhesive. As mentioned before, the periodic breaks shown in the module illustration are to remove redundant portions of the module which may extend for over one hundred feet with numerous pitch reversals, it being understood that where used, the relative location of annular spacers 31 on their respective nodes are midway between successive pitch reversal locations 17. The viscous fill fluid 23 fills the space between the compliant core and the inner wall of the jacket 20 and provides for viscous damping.
The end caps for the embodiment of FIG. 4 have different configurations from those shown in earlier figures. Cap 27 and the opposite end cap (not shown in the drawings) each have a hose clamp 27a' holding jacket 20 on the end caps to permit longitudinal load sharing. The essentially nonextensible cord-like members extend through the cap in suitable terminations 25a'". The end portion 15a' of the elastomeric core need not be bonded into a recess provided in the end cap 27 because the nonextensible cords lie in the helically extending grooves provided within the elastomeric core 15' and 15a', and the grooves in the core are keyed to the holes in the end caps, through which the cords pass and are terminated. In like manner, the opposite end of the vibration isolation module has the cord-like members terminated in the end cap there.
Referring now to part A of FIG. 5 of the drawings, an elastomeric core 15 has a single nonextensible cord-like member helically wrapped around it with a single pitch reversal at 15a. The upper portion of the figure has an N-turn right-hand helix extending for a distance of "a" (one half the length of the compliant core 15). At the point of pitch reversal 15a (the point where the nonextensible member is secured to the compliant core in the embodiments of FIGS. 2 and 3 or where the helical grooves reverse their pitch in the embodiment of FIG. 4) a series of N left hand helical turns continues down the core for a distance "a". The pitch of the helix, which is the axial distance per turn, is the ratio of the length "a" over the number of turns "N" in that length as they wrap around the core of diameter "2R". The initial helix angle θ, is the angle which the helically wound essentially nonextensible cord-like member makes with respect to the plane normal to the axis of the core. It can be visualized for study by unwrapping the imaginary right triangle shown in the upper part of part B of FIG. 5, from around the core. One will note that the hypotenuse of this triangle, which is of length "l", corresponds exactly to the length of the essentially non-extensible cord-like member. The right triangle shown in the lower portion of part B of FIG. 5 is the distorted version of the upper triangle that accompanies the longitudinal elongation or stretching of "a" by an amount "Δa" when the cord length "l" remains unchanged during the process. Equating the two expressions for "l" leads to equation (1) of part C of FIG. 5, which represents the case in which the cord has infinite longitudinal stiffness. If, on the other hand, the longitudinal stiffness of the cord, although still greater than that of the core, is somewhat more comparable to that of the core, computations must also allow for a stretching of the cord. This stretching causes "l" to increase by an amount "Δl" when "a" increases by an amount "Δa". Making this modification, leads to equation (5) of part C of FIG. 5, which relates the number of forced rotations of the core at the pitch reversal point to the stated parameters and variables which include the strain in the cord and the longitudinal strain in the core assembly.
Referring to equation (1) in part C of FIG. 5, as the length of a vibration isolation module of part A undergoes a longitudinal strain, the number of turns or rotations at the pitch reversal point with respect to the end caps, is given by the quantity ΔN. The theoretical taut limit, which is the maximum amount the vibration isolation module of part A could be hypothetically stretched if the cords were truly nonextensible, would occur when the quantity B equals 1 and ΔN=-N. At this condition, the nonextensible cord-like member 25 would be under infinite tension and would be stretched straight between opposite ends of the module. At the other extreme is the zero response or zero rotation condition that occurs whenever the reduction in cross-section of the core due to the Poisson effect and the change in pitch of the essentially nonextensible cord-like member occurring when the core is stretched balance each other without the need for any core rotation at the pitch reversal point. This ΔN=0 condition occurs whenever condition (4) of part C of FIG. 5 is satisfied.
Looking to FIG. 6 several curves have been plotted to show the nonlinearity of the relation between longitudinal strain of the module and the parameter B for several initial helix angles of the essentially nonextensible member. A helix angle (theta)=57.7° (W=2.5), provides a buildable design with good dynamic range and desired operating characteristics. The one-inch diameter core fabricated from the VAMAC material has performed satisfactorily for the dynamic towing speeds of interest, and when used with longitudinally stiff, KEVLAR low-angle braided cord it provided characteristics similar to those shown on FIG. 6.
FIG. 7A depicts the permissible operating region for a KEVLAR-corded core having a σ=0.5 which lies between the taut limit of B=1 and the zero response floor of B=0. Within the permissible operating region shown, the helix angles could have the values set out in FIG. 6, and no severe limitations were apparent. The better choices for the initial helix angle at which the helically extending essentially nonextensible members are wrapped about the elastomeric core, varies from one cord material to another and from one core material to another and with the loads imposed by the dynamic operating range of the towed instrumentation package. However, with the many choices available in materials and parameters a designer has wide latitude in selecting the optimum design and can feel reasonably secure that destructive shocks and longitudinal motional disturbances will be effectively dissipated by the vibration isolation module. FIG. 7B and 7C present contrasting tension versus longitudinal strain curves for similarly sized core assemblies. FIG. 7B was obtained using a low modulus core and KEVLAR cords, and 7C, was obtained using a high modulus core and much more compliant double-braided nylon/polypropylene cords of a slightly larger diameter.
The tensile reaction for small extensions is dominated by the initial pitch of the cord-like torsion producing member and the elastic properties of the core. The tensile reaction for large extensions are dominated by the elastic properties of the cord-like torsion producing members, themselves, allowing appropriate selection of the initial and final slopes of the tension vs. elongation curve and the location of the knee therein. Also, when the rate of longitudinal extension is sufficiently increased (as can occur for a given vibrational amplitude when the frequency is increased or when one end of the module is subjected to large sudden excursions) the resistance of the core to changes in angular momentum must be taken into account. The resulting effect, which is related to both the time rate of change of angular momentum of the core and the instantaneous helix angle of the cord-like members, is to increase the apparent longitudinal stiffness of the module. Fortunately, the magnitude of this effect is proportional to the spacing between successive pitch reversals, and so adjusting the distance between pitch reversals provides an independent design tool for dealing with this effect.
Modifications of the disclosed concept lend themselves to a host of unique applications all of which serve to dissipate longitudinal shocks and motional disturbances. In FIG. 8 a vibration isolation module 10 is interposed between a tug and a barge. Note that the hawsers 14 are short compared to the lengths of line which normally separates a tug and barge. Conventionally, long towing hawsers have been found to be a necessary expedient to provide for an acceptable lessening of the effects of the yawing, heaving, pitching motions and other unsteady loads associated with towing. In addition to reducing the controllability of the barge the long hawsers store considerable energy and pose a real hazard if accidentally parted.
The vibration isolation module fabricated to anticipate the dynamic towing loads would necessarily have a larger core or consist of a number of such cores in parallel each having associated helically wound nonextensible members to bear the load. The severe strain that may result from high wind and storm conditions could be accommodated by a suitably designed nonlinear vibration isolation module without exposing the men and equipment to unacceptable hazards.
The vibration isolation module can also serve in an oceanographic application as a damper for suspended loads, see FIG. 9. The wave induced motion of a supporting surface platform represented by buoy 37 is dampened by a vibration isolation module 10 from reaching a suspended, weighted instrumentation package 38. The materials of the vibration isolation module can be chosen to assure a soft damping and dissipation of the buoy induced motions during calm spells. The nonlinearity of the modules will also prevent severe shocks from being transmitted during severe sea states.
A further application of the vibration isolation module is its use as a motion arresting device 10 in a restraining harness. Harnesses of this type are generally found in high-performance aircraft and other vehicles. A number of elastomeric cores 15 are disposed in a parallel relationship and each have a number of essentially nonextensible cord-like members helically wrapped thereabout with one or several pitch reversals. A strong back 39 and an anchor 40 at opposite ends coupled the modules to the arresting harness and to an anchor point to cushion the shocks and motional disturbances otherwise attributed to the violent maneuvering of such high speed craft.
Obviously many modifications and variations of the present invention are possible in the 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. | Longitudinal shocks and longitudinal emotional disturbances are reduced between members attached to opposite ends of a vibration isolation module. An elongate, essentially cylindrically shaped cord extends the length of the module and is fabricated from a compliant and dissipative material. At least one cord-like essentially nonextensible member is wound about the core in a helical fashion with at least one symmetrically located pitch reversal, and with attachment to the core at least at the ends and pitch reversal points. Longitudinal shocks and motional disturbances are translated by the essentially nonextensible cord-like member into torsional shear strains in the compliant core. The dissipative characteristics of the core material coupled with the nonlinear relationship between longitudinal and torsional strain produce a tensile shock absorber with both damping and a spring constant that increases with longitudinal strain. A flexible outer jacket covers the core and cord-like nonextensible members and help share the shocks and motional disturbances as well as containing a fill fluid that aids the core and jacket by viscously dissipating part of the shocks and motional disturbances, including a series of helical pitch reverses in the nonextensible cord-like member along a module's length and having annular spacers disposed between the core and jacket and located at nodes between successive pitch reversals helps assure the integrity of the module and presents a streamlined surface to reduce the problems associated with excessive flow noise. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 60/151,971, filed Sep. 1, 1999. More than one reissue application has been filed for U.S. Pat. No. 6,181,120. Specifically, application Ser. No. 10/375,914 was filed on Feb. 26, 2003 as a continuation of the present application, Ser. No. 10/045,169.
FIELD OF THE INVENTION
The present invention relates to DC/DC converters.
BACKGROUND OF THE INVENTION
As the complexity and clock speed of CPUs continue to rise, greater demands are placed on the power supplies (DC/DC converters) that supply the operating voltage to the CPUs. Typically, the operating voltage of CPUs is specified with a relatively tight tolerance to ensure proper operation of the CPU. The tight tolerances on CPU operating voltages are being further narrowed as CPU clock and CPU bus speeds increase, and CPU operating voltages decrease. The decrease in permissible tolerances on CPU operating voltages has resulted in a corresponding increase in the regulation specifications of power supplies that supply operating voltages to CPUs.
The current drawn by a CPU generally undergoes frequent variation and rapid changes of substantial magnitude. For example, the current a CPU draws from a power supply may change by as much as 10-75 Amps per microsecond. These frequently varying and rapidly changing demands for substantial amounts of current are referred to as load transients. These extreme load transients cause a corresponding voltage transient on voltage output of the power supply, thereby making it very difficult for a power supply to comply with tight power supply regulation specifications. Many power supplies incorporate very large capacitors to reduce the effect of these large and rapid load transients, and thereby lessen the resultant corresponding voltage transients on the output voltage of the power supply to an acceptable level. However, the use of large capacitors adds significantly to the cost, size and weight of the power supply.
In order to reduce the number and size of capacitors needed to lessen the effect of a given load transient on power supply output voltage, a technique known as “droop” is employed. Normally, power supplies are designed to have an output voltage that is essentially independent of the load current. However, in applications where a power supply will be required to comply with tight regulation specifications in a high-load-transient environment, there is an advantage in carefully controlling and/or adjusting the output impedance of the power supply to thereby cause the power supply output voltage to decrease by a predetermined amount in response to an increase in current demanded by or being supplied to the load.
In conventional current-mode DC/DC converters, the duty cycle of the DC/DC converter is modulated by a negative-feedback voltage loop to maintain the desired output voltage. The feedback voltage loop has a DC voltage gain which determines the amount of “droop” in the output impedance of the power supply. The DC voltage gain of the feedback loop is, therefore, designed to be relatively low in order to achieve a relatively small amount of droop and thereby maintain a substantial degree of voltage regulation to comply with the tight tolerances placed upon the operating voltage supplied to the CPU.
The low DC gain in the feedback loop, however, results in any variations or offsets in the voltages within the DC/DC converter being reflected in a corresponding error in the output voltage of the converter. The only known solution to this problem is to design precise circuitry using components having tight tolerances in order to achieve low-offset voltages and/or precise internal voltages within the DC/DC converter. The inclusion of such precise circuitry adds substantially to the cost and complexity of the converter.
Therefore, what is needed in the art is a converter that maintains voltage regulation in a high-load-transient environment.
Furthermore, what is needed in the art is a converter which does not depend upon large capacitors to maintain voltage regulation in a high-load transient environment, and is therefore less expensive to build, smaller in size and lighter in weight.
Moreover, what is needed in the art is a converter which achieves voltage regulation in a high-load transient environment without the use of precision circuitry, and is therefore less complex and less expensive to build.
SUMMARY OF THE INVENTION
The present invention provides a DC/DC converter having a controlled output impedance and which provides for a controlled droop in the output voltage in response to load transients.
The invention comprises, in one form thereof, a DC/DC converter having an output voltage and sourcing an output current to a load. The DC/DC converter includes an error amplifier with a reference input and a summing input. The reference input is electrically connected to a reference voltage. The summing input is electrically connected to the output voltage and the output current. The summing input is configured for adding together the output voltage and the output current. The error amplifier issues an error signal and adjusts the error signal dependent at least in part upon the output voltage and the output current. A comparator receives the error signal. The comparator has a ramp input electrically connected to a voltage ramp signal. The comparator issues an output signal that is based at least in part upon said error input. A power switch has an on condition and an off condition, and supplies dc current to the load when in the on condition. The power switch has a control input electrically connected to the comparator output signal. The power switch is responsive to the control input to change between the on condition and the off condition to thereby adjust the output current of the DC/DC converter.
An advantage of the present invention is that droop in the output voltage of the converter in response to a load transient is controlled and reduced.
Another advantage of the present invention is that the need for a plurality of large capacitors to maintain regulation of the output voltage in a high-load transient environment is eliminated, and therefore the present invention is less expensive to manufacture, is of a lighter weight and smaller in size than conventional DC/DC converters.
A further advantage of the present invention is that it is essentially immune to errors in internal reference and offset voltages.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become apparent and be better understood by reference to the following description of one embodiment of the invention in conjunction with the accompanying drawings, wherein:
FIG. 1A includes a pair of graphs illustrating how conventional converters droop when a load is applied and then removed.
FIG. 1B includes a pair of graphs that show how the present invention improves droop when a load is applied and then removed;
FIG. 2 is a schematic of a conventional converter;
FIG. 3 is a schematic of one embodiment of a current mode DC/DC converter with controlled output impedance of the present invention; and
FIGS. 4A and 4B show examples of the summing circuit of FIG. 3 ;
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates one preferred embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and particularly to FIG. 1A , the effect of a load transient upon the output voltage of a conventional converter is illustrated. The targeted no-load output voltage of the converter is V TARGET1 . The actual no-load output voltage of the converter is V 1A . In the case of FIG. 1A , V TARGET1 is intentionally set equal to V 1A . A load current transient occurs at time T 1A , which results in a contemporaneous and corresponding droop in the converter output voltage to a level below V TARGET1 . As the demand for load current reduces at time T 1A +1, a contemporaneous and corresponding spike in the converter output voltage to a level above V TARGET1 is observed.
Referring now to FIG. 1B , the effect of the same load current transient as shown in FIG. 1A is illustrated on a converter having a targeted no-load output voltage of V TARGET2 . However, in the case of FIG. 1B , the actual no-load output voltage of the converter V 1B is intentionally set to be a predetermined amount greater than V TARGET2 . By intentionally setting V 1B a predetermined amount greater than V TARGET2 , the load transient at time T 1B results in a smaller-magnitude droop in the converter output voltage. More particularly, the droop in output voltage in FIG. 1B is only one-half the magnitude of the droop in converter output voltage observed in FIG. 1 A. Thus, for a given load transient and a fixed amount of converter output capacitance, a designer can reduce by one-half the amount of droop in the output voltage of the converter by setting the actual no-load output voltage of the converter to be a predetermined amount greater than the targeted no-load output voltage. Alternatively, the amount of converter output capacitance can be dramatically reduced while maintaining a given amount of droop in the converter output voltage in response to the same given load transient by setting the actual no-load output voltage of the converter to be a predetermined amount greater than the targeted no-load voltage.
Referring now to FIG. 2 , the operation of conventional current-mode DC/DC converter 10 is described. A constant-frequency signal CLK sets SR-Latch 12 and turns on power switch 14 once per every cycle of the constant-frequency signal CLK. Power switch 14 remains on for a fraction of the cycle of the CLK signal (known as the “Duty Cycle”) as determined by the output of comparator 16 . During the “off-time” of power switch 14 , diode 18 conducts current flowing through inductor 20 to load 22 . In an alternate configuration, diode 18 is replaced by a second power switch (not shown), which is controlled in a complementary fashion to power switch 14 . Such a configuration is known as Synchronous Rectification.
As will be described in more detail hereinafter, the duty cycle of DC/DC converter 10 is modulated by a negative-feedback voltage loop to maintain the desired output voltage V OUT across load 22 . In a current-mode converter (as in FIG. 2 ), output voltage regulation is achieved in an indirect fashion by controlling a sensed current. The current through power switch 14 is sensed, and therefore controlled, by current sensor 24 , and signal V ISENSE , which is proportional to the current sensed by current sensor 24 , is issued. However, it is to be understood that either the current through inductor 20 or the current through diode 18 can be sensed instead.
To achieve output voltage regulation, output voltage V OUT is sensed and divided down by the voltage divider formed by R 1 and R 2 to produce the voltage V FB at node 26 . Error Amp 28 amplifies the difference between V FB and the voltage reference V REF at node 30 and produces the error voltage V ERROR at node 32 . Thus, error amp 28 adjusts the V ERROR voltage at node 30 as needed to achieve a power switch 14 duty cycle that forces V FB at node 26 to be equal to V REF . Subtraction circuit 35 subtracts V ISENSE from V ERROR . Because the current sensed by current sensor 24 is subtracted from V ERROR in the form of V ISENSE , error amp 28 also adjusts V ERROR at node 32 in accordance with V ISENSE to produce the needed duty cycle. This results in an effective control, or programming, of the current sensed by current sensor 24 . Depending on the gain of the signal conditioning block 36 , the V ERROR signal at node 32 can be proportional to the intra-cycle peaks of the sensed current (known as Peak Current Control) or the V ERROR signal may be proportional to the average value of the sensed current (known as Average Current Control).
To implement either Peak Current or Average Current Control, it is necessary to add frequency compensation to the voltage feedback loop to achieve stability. Frequency compensation is accomplished by C COMP and R 1 . C COMP and R 1 add a high-frequency pole into the feedback loop that cancels a zero that is due to the Equivalent Series Resistance (ESR) of the output capacitor C L . Depending on the details of the circuit values, this compensating pole is sometimes not needed. The feedback resistor R FB is adjusted to control the DC gain of error amplifier 28 , and thereby provide the desired amount of droop in the output voltage V OUT of converter 10 . Since the voltage V ERROR at node 32 is proportional to V ISENSE , which represents the current sensed by current sensor 24 and which is proportional to load current I OUT , a reduction in DC gain will cause the output voltage V OUT to vary with the load current I OUT . In this manner, a controlled droop in the output impedance of converter 10 is achieved. For example, the voltage V ISENSE may vary by 2V as the load current I OUT varies from 0 to 10 Amps. If the ratio of R FB to R 1 , is equal to 10 (ten), the voltage V OUT will decrease by 0.1V as the load current is increased from 0 to 10 Amps (hence, “Droop”).
The fundamental problem with the method of converter 10 in achieving and controlling droop resides in the low DC gain of the voltage feedback loop. This low gain is used to provide the drooping characteristic, but it also has an undesirable side-effect. As a result of this low DC gain, any variations in the V RAMP signal or DC offsets in current sensor 24 or comparator 16 will be reflected in a corresponding error in the voltage V OUT . For example, if the average value of the voltage V RAMP has tolerance of ±200 mV, and the ratio of R FB to R 1 is equal to 20, an additional error term of ±10 mV on the voltage V OUT will result. The only known solution to this problem is to design precise circuitry in order to achieve low-offset voltages and/or a precise V RAMP voltage. The inclusion of such precise circuitry adds substantially to the cost and complexity of a DC/DC converter.
Referring now to FIG. 3 , there is illustrated one embodiment of an improved current-mode DC/DC converter 100 of the present invention. DC/DC converter 10 includes SR latch 112 having a constant-frequency signal CLK which sets latch 112 which, in turn, turns on power switch 114 . Power switch 114 , although shown schematically as a conventional switch, is a transistor-based switch having one or more power transistors configured to source current in response to an input signal, which is the output of latch 112 . Switch 114 remains in the on state for a fraction of the period of the CLK signal, which is known as the duty cycle, as determined by comparator 116 . The current flowing through load 122 is sensed by current sensor 124 , which issues signal V ISENSE . The duty cycle of power switch 114 is modulated by a negative voltage feedback loop. Voltage V FE at node 126 is input to error amplifier 128 . Summing circuit 129 sums voltages V ISENSE and V OUT . This summed voltage is then divided by a voltage divider formed by R1 and R2, thereby creating voltage V FE at node 126 . Thus, V ISENSE is a component of V FB . Error amplifier 128 compares V FB with V REF , thereby creating V ERROR . Comparator 116 compares V ERROR with V RAMP . The output of comparator 116 periodically resets latch 112 to thereby determine the duty cycle of power switch 114 . Error amplifier 128 includes, in its negative voltage feedback path R COMP and C COMP , which provide for the frequency compensation of V FB . The gain of error amplifier 128 is determined by the ratio of R COMP to R 1 .
The most fundamental feature of DC/DC converter 100 is that current sensor 124 is electrically connected to the output voltage feedback loop. More particularly, V ISENESE is divided by the voltage divider formed by R 1 and R 2 , and this divided portion forms part of V FB . However, it is to be understood that the current through inductor 120 or the current through diode 118 can be sensed and similarly connected to the output voltage feedback loop, rather than the current through power switch 114 . V ISENESE is connected to the voltage feedback loop without first being frequency compensated by error amplifier 128 , as in conventional DC/DC converter 10 of FIG. 2 . The principle advantage of not performing frequency compensation upon signal V ISENESE prior to the connection thereof with the output voltage feedback signal is that the gain of error amp 128 is thereby permitted to be arbitrarily high at DC (note the absence of RF), thus providing DC/DC converter 100 excellent output voltage accuracy that is essentially immune to variations in the V RAMP voltage and offset voltages, etc.
To understand how DC/DC converter 100 creates the desired drooping output voltage characteristic, first consider the operation of DC/DC converter 100 under a no-load condition with I OUT =0. In this case, V ISENSE =0, and the output voltage V OUT of converter 100 , under this no-load condition, is given by Vref (R 1 +R 2 )/R 2 . Note that R 1 and R 2 here are intentionally chosen so that the no-load output voltage of converter 100 is a predetermined amount greater than the desired target voltage. At full load, when I OUT =I MAX , V ISENSE will equal V ISENSE, MAX , and thus we have V OUT =[V REF (R 1 +R 2 )/R 2 ]−V ISENSE,MAX . Thus, as the current through load 122 increases from zero to full load current, output voltage V OUT decreases, or droops, by V ISENSE,MAX Volts.
Note especially that the same frequency compensation provided by R COMP and C COMP is applied to both the V FB voltage signal and the V ISENSE current signal. In this way, average current mode control is implemented without the need for a separate signal conditioning block (Gc(s) in FIG. 2 ). This is another advantage of DC/DC converter 100 . Average current mode control and accurate droop are achieved using a single amplifier. The frequency compensation in DC/DC converter 10 introduces a pole at very low frequency, which is set by the characteristics of error amp 128 , and a zero which is set by R COMP and C COMP . For the voltage feedback loop, a high DC gain is provided, which makes the output voltage of DC/DC converter 100 essentially immune from errors in V RAMP and offset voltage errors. Likewise, in regards to current, the high DC gain and averaging characteristic of the frequency compensation provide excellent response to the average value of the sensed current. Because of the current-mode control, the two poles associated with the LC filter formed by inductor 120 and load capacitor 121 are split, with one pole moving to a relatively high frequency and the other pole moving to a relatively low frequency. The zero is placed before the crossover of the frequency compensation loop, which effectively cancels the effect of the low-frequency pole associated with the LC filter formed by inductor 120 and load capacitor 121 . The high frequency gain of error amp 128 is determined by the ratio R COMP /R 1 . This ratio is adjusted to provide suitable high frequency current gain (and the associated pole-splitting of the LC filter poles). The high-frequency pole associated with the LC filter formed by inductor 120 and load capacitor 121 is used to compensate for the zero associated with the ESR of load capacitor 121 . In this manner, a response that is essentially a single-pole response having excellent phase margin is achieved.
Referring now to FIGS. 4A and 4B , two practical circuits are illustrated for the summing of V OUT and V ISENSE . In FIG. 4A , error amplifier 128 is configured as a summing amplifier to sum voltages V OUT and V ISENSE . R 3 has been added between current sensor 124 and node 126 . Note that, in the configuration of FIG. 4A , it is necessary to divide the voltage V REF by a factor of two to obtain the correct output voltage V ERROR . In FIG. 4B , the sensed current signal is summed into the V FB node 126 as a current. This is a particularly useful approach, because it allows the voltage V REF to be used directly, rather than being divided by two, and also allows the magnitude of the droop to be easily adjusted by varying the value of R 1 .
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the present invention using the general principles disclosed herein. Further, this application is intended to cover such departures from the present disclosure as come within the known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | A DC/DC converter has an output voltage and sources an output current to a load. The DC/DC converter includes an error amplifier with a reference input and a summing input. The reference input is electrically connected to a reference voltage. The summing input is electrically connected to the output voltage and the output current. The summing input is configured for adding together the output voltage and the output current. The error amplifier issues an error signal and adjusts the error signal dependent at least in part upon the output voltage and the output current. A comparator receives the error signal. The comparator has a ramp input electrically connected to a voltage ramp signal. The comparator issues an output signal that is based at least in part upon said error input. A power switch has an on condition and an off condition, and supplies dc current to the load when in the on condition. The power switch has a control input electrically connected to the comparator output signal. The power switch is responsive to the control input to change between the on condition and the off condition to thereby adjust the output current of the DC/DC converter. | 7 |
ORIGIN OF THE INVENTION
The invention described herein was made in the performance of official duties by employees of the Department of the Navy and may be manufactured, used, licensed by or for the Government for any governmental purpose without payment of any royalties thereon.
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
This patent application is co-pending with two related patent applications entitled "AIR-SAFED MECHANICAL WATER ACTUATOR" filed Sep. 19, 1998 as U.S. patent application Ser. No. 09/156,382, and "LOCK AND RELEASE MECHANISM" filed Dec. 15, 1998 as U.S. patent application Ser. No. 09/211,002, and, owned by the same assignee as this patent application.
FIELD OF THE INVENTION
The invention relates generally to fuzes or fuze systems for use with launched munitions, and more particularly to an air-safed underwater fuze system that is readied at launch and causes detonation only when submerged in water.
BACKGROUND OF THE INVENTION
In general, military specifications define a fuze or fusing system as a physical system designed to sense a target or respond to one or more prescribed conditions such as elapsed time, pressure or command, and initiate a train of fire or detonation in munitions. Safety and arming are primary roles performed by a fuze to preclude ignition of the munitions before the desired position or time. For example, if a munitions is an array of energetic charges launched from a watercraft into shallow (or deep) water to clear mines and obstructions, the fuze should ideally determine that launch and deployment occurred as intended before initiating detonation. Several fuzes designed to just prevent in-air detonation are known in the prior art.
U.S. Pat. Nos. 3,765,331 (the '331 patent) and 3,765,332 (the '332 patent) disclose water-armed air-safetied detonators in which a plurality of small explosives are aligned in a spaced-apart fashion in a fuze housing. The first of these small explosives is a delay charge which ignites when the ordnance is launched or released. The delay charge eventually burns and flashes down an adjacent housing bore to ignite a transfer charge. Detonation of the transfer charge releases energy that is either used to move a piston (the '331 patent) or is in the form of a shock wave (the '332 patent). This released energy is delivered to a chamber that is flooded with either air or water depending on the environment in which the fuze is immersed. Adjacent the flooded chamber is a firing pin/percussion primer (the '331 patent) or just a percussion primer (the '332 patent). If the flooded chamber is filled with air, the released energy in the form of a moving piston (the '331 patent) or shock wave (the '332 patent) will not transfer through to the next stage of the fuze. If, however, the fuze is submerged in water, the flooded chamber is filled with water and the released energy entering the flooded chamber is transferred therethrough to the next stage of the fuze.
Although being air-safed, these devices still have several disadvantages. Use of stored energy (i.e., explosive material) for arming and firing is considered bad design practice because the energy is available at all times during storage and transportation, and may therefore be released due to unforeseen causes or situations. The use of explosives as part of the fuze train can be inherently problematic. These problems range from the safety concerns related to the construction and storage of such devices to the fact that these fuzes are not reusable.
To overcome the problems inherent with the use of explosives, a mechanical underwater firing mechanism is disclosed in U.S. Pat. No. 2,660,952. Briefly, a spring-loaded plunger is mounted in a housing. The head of the plunger is formed with a recess. Fitted in the housing coaxial with the plunger is a plug having a central bored portion in which a firing pin is temporarily positioned intermediately therein by a shear pin. As a result, small chambers are defined in the central bored portion on either side of the firing pin. The central bored portion of the plug opposes the plunger's recess and is sized at its exterior to fit within the recess. When the spring-loaded plunger is cocked, the head of the plunger is spaced apart from the central bored portion of the plug to define a chamber within the housing. An opening in the side of the housing at the chamber allows the environment surrounding the housing (e.g., air or water) to fill the chamber.
When the spring-loaded plunger is released, the plunger recess envelops the central bored portion of the plug to compress any fluid trapped in the small chamber of the central bored portion between the firing pin and the head of the plunger. If the trapped fluid is air, the compression thereof will not develop forces sufficient to cause the shear pin to fail. However, if the trapped fluid is water, the compression forces imparted by the plunger will be sufficient to cause failure of the shear pin thereby allowing movement of the firing pin to impact a primer.
While eliminating the use of explosives in the firing mechanism, this device has other disadvantages. For example, the requirement that a small chamber be defined in the central bored portion opposing the head of the plunger raises the possibility that an air bubble will form therein when the device is submerged in water. The presence of such an air bubble could prevent the mechanism from functioning underwater. At the same time, the requirement that the small chamber be present in the central bored portion could also bring about an unwanted firing. This could occur if the mechanism were not cocked and inadvertently dropped in water. Water could seep into the mechanism and fill the small chamber. Then, an in-air release of the (cocked) plunger could bring about movement of the firing pin just as if the mechanism were submerged in water. Another disadvantage brought about by the requirement of the small chamber arises in sub-freezing environments. Specifically, water in the small chamber could quickly freeze due to its small volume. If this occurs, the mechanism will not function.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an air-safed underwater fuze for launched munitions.
Another object of the present invention is to provide an air-safed underwater fuze for launched munitions that is readied only at time of launch.
Still another object of the present invention is to provide an air-safed underwater fuze that can initiate detonation only when submerged in water.
Other objects and advantages of the present invention will become more obvious hereinafter in the specification and drawings.
In accordance with the present invention, a fuze system is provided for munitions that are to be launch-deployed and water-detonated. A housing defines a first bore contiguous with a second bore. One or more radial ports formed in the housing allow an environment about the housing to communicate with the first bore. A first piston is slidably mounted in the first bore and a second piston is slidably mounted in the second bore and positioned flush with the first bore. Piston control means are coupled between the munitions and first piston for positioning the first piston in a first position prior to launch. In the first position, the first piston seals off the radial port(s) while being spaced apart from the second piston so that a chamber in the first bore is defined between the first and second piston. The piston control means moves the first piston at launch to a second position so that the chamber expands and the radial port(s) are in communication with the chamber. As a result, fluid in the environment about the housing can fill the chamber. The piston control means further drives the first piston from its second position towards its first position at a specified time after launch. Once the first piston seals off the radial port(s), the first piston pressurizes the fluid in the chamber. If the fluid is water, the second piston is driven along the second bore as actuating movement. A firing mechanism is provided in communication with the second bore and coupled to the munitions. The firing mechanism is responsive to the actuating movement of the second piston to generate detonation energy for the munitions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side sectional view of an embodiment of the air-safed underwater fuze system of the present invention in its at-rest state;
FIG. 2 is a side sectional view of the fuze system in its readied state;
FIG. 3 is a side sectional view of the fuze system in transition from its readied state to its at-rest state; and
FIG. 4 is a side sectional view of the fuze system after transition from its readied state to its at-rest state assuming the fuze is submerged in water;
FIG. 5A is an enlarged partial side sectional view of another embodiment of the piston used to trigger the fuze system's firing mechanism;
FIG. 5B is a sectional view taken along line 5--5 of FIG. 5A;
FIG. 6A is an enlarged partial side sectional view depicting another embodiment of a piston safety restraining mechanism when the fuze system is at-rest;
FIG. 6B is the piston safety restraining mechanism of FIG. 6A when the fuze system is in its readied state; and
FIG. 6C is the piston safety restraining mechanism of FIG. 6A when the fuze system has been activated.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, FIGS. 1-4 depict an operational sequence of the fuze system of the present invention for use with launched munitions. Accordingly, the reference numerals will be the same for the common elements in each of the views. The fuze system is referenced generally by numeral 10. By way of example, fuze system 10 is coupled inline with a projectile 100 and one or more line charges 102 to be detonated in a water environment. Projectile 100 can receive its launch power from a launcher (not shown) or can be capable of self-propulsion via rockets, motors, etc. Charges 102 are main charges which are generally insensitive and require specific initiation provided by fuze system 10 at the appropriate time.
Also, by way of example, fuze system 10 is illustrated and will be described for use in harsh environmental conditions where sub-freezing air (e.g., on the order of 0° F. or less) and seawater (e.g., on the order of 27-29° F.) temperatures are expected. Note that the freezing temperature of seawater is generally less than 32° F. and can be considerably lower depending on salinity. However, it is to be understood that the present invention is not limited to use in such harsh environmental conditions.
The pre-launch or at-rest state of fuze system 10 illustrated in FIG. 1 will be referred to first to describe the component parts thereof. A rigid housing 12 defines a first bore 14 and a second bore 16 therein. Bores 14 and 16 are adjoined and can be coaxially-aligned with one another along longitudinal axis 11 as in the illustrated embodiment. However, bores 14 and 16 could also be offset slightly with respect to their longitudinal axis or be angularly disposed with respect to one another. In the illustrated embodiment, the diameter of bore 14 is larger than that of bore 16 such that the cross-sectional area of bore 14 is at least several times that of bore 16. In some applications, bores 14 and 16 could have the same diameter. Also defined in housing 12 are one or more ports 18 linking the exterior of housing 12 with bore 14. Typically, ports 18 extend radially outward from bore 14 about the circumference of housing 12.
Disposed within bore 14 is a piston 24 mounted for sealed but sliding engagement in bore 14 in any of the conventional ways known in the art. For example, a ring seal (not shown for sake of clarity) can be retained in a circumferential notch 24A of piston 24. In the at-rest position, piston 24 is positioned such that ports 18 are sealed with respect to bore 14 and a chamber 22 is defined in bore 14 between piston 24 and the start of bore 16. The sealing of chamber 22 from ports 18 is insured by notch 24A (holding a ring seal) being positioned between ports 18 and the end of piston 24 facing chamber 22. The reasons for sealing off ports 18 from chamber 22 in this at-rest position will be explained in detail below.
Disposed in bore 16 is another piston 26 mounted for sealed but sliding engagement in bore 16. Accordingly, a ring seal (not shown for sake of clarity) can be retained in a circumferential notch 26A of piston 26. Note that the ring seal in notch 26A completes the sealing of chamber 22 between pistons 24 and 26. In the at-rest position, piston 26 is positioned so that it is flush with bore 14 for reasons that will be explained in detail below. Retention of piston 26 in the at-rest position can be passive (i.e., by means of the sealing strength of the ring seal in notch 26A) or can be active as illustrated. More specifically, the at-rest position of piston 26 can be maintained by providing a shear pin 28 coupling piston 26 to housing 12. In the illustrated example, shear pin 28 is inserted through housing 12 for ease of assembly. Other types of positioners (e.g., spring) or safety restraints can be used as long as they fail or yield at the appropriate time as will be explained further below.
Coupled to or integral with (as shown) piston 24 is a piston rod 30 that extends back through bore 14 and out of housing 12. Outboard end 30A of piston rod 30 is mechanically coupled to the last of line charges 102 either directly or via a lanyard 104 as in the illustrated embodiment. A lock and release mechanism 32 positioned in (as shown) or out of housing 12 is provided for engaging or disengaging from piston rod 30. Lock and release mechanism 32 is a mechanical device such as a ball lock type device. One suitable lock and release mechanism is disclosed in the afore-mentioned co-pending patent application entitled "LOCK AND RELEASE MECHANISM" U.S. patent application Ser. No. 09/211,002, the contents of which are hereby incorporated by reference.
In order to mechanically load piston 24, a spring 34 is provided in bore 14 about piston rod 30. Specifically, spring 34 is captured between piston 24 and the terminal end 14A of bore 14. To position piston 24 in its at-rest position, lock and release mechanism 32 is disengaged from piston rod 30 and spring 24 is selected to have an at-rest or maximum travel state that properly positions piston 24 as described above. A release actuator 36 is coupled to lock and release mechanism 32 and a timer 38 is coupled to release actuator 36. In general, timer 38 is configured to countdown a specified time period. At the conclusion of the specified time period, release actuator 36 activates the release mechanism of lock and release mechanism 32 which, in turn, will then disengage from piston rod 30.
Operation of fuze system 10 will now be explained beginning with the at-rest position illustrated in FIG. 1. In this position, spring 34 is at-rest and chamber 22 is sealed from the outside environment. At launch, projectile 100 and line charges 102 begin to move in the direction of arrow 40. As the last line charge 102 takes off, lanyard 104 is placed in tension. In turn, piston rod 30 is extracted from housing 12 in the direction of arrow 42 as depicted in FIG. 2 to draw piston 24 along bore 14 and compress spring 34. Spring 34 thus supplies a potential energy bias to piston 24. Lock and release mechanism is designed to lock onto piston rod 30 once spring 34 is compressed thereby maintaining piston 24 in its ready state. Timer 38 can be activated to start its countdown either at launch or once lock and release mechanism 32 locks onto piston rod 30.
The length of bore 14 and configuration of spring 34 are designed to allow piston 24 to clear ports 18 as piston rod 30 is extracted from housing 12 by lanyard 104. As chamber 22 expands, ports 18 communicate therewith as shown in FIG. 2. Once housing 12 is submerged in water, the water is admitted into (expanded) chamber 22 via ports 18.
Timer 38 is pre-set to countdown the expected time it takes for line charges 102 to reach their destination in water. At the conclusion of this time, release actuator 36 activates the release mechanism of lock and release mechanism 32. Lock and release mechanism 32 is thus disengaged from piston rod 30 with spring 34 compressed as in FIG. 2. Once this occurs, piston 24 begins to move in the direction of arrow 44 (as depicted in FIG. 3) under the bias force of spring 34 which is in transition to its at-rest state. After piston 24 has again sealed off ports 18 as in FIG. 3, the water in chamber 22 is pressurized. The pressure in chamber 22 builds against piston 26 until shear pin 28 fails. At this point, as illustrated in FIG. 4, piston 26 is driven along bore 16 in the direction of arrow 46. The movement of piston 26 is used to trigger the fuze system's firing mechanism.
While a variety of firing mechanisms could be incorporated into fuze system 10, one firing mechanism currently in use by the U.S. Navy will be described by way of example. Briefly, a wedge 50 incorporates a detonator 52 and lead line 54, and is mounted in housing 12 such that wedge 50 is constrained to transverse movement relative to the axial movement of piston 26. More specifically, wedge 50 moves transverse to piston 26 when struck thereby. Such transverse movement of wedge 50 causes detonator 52 to be impaled by a firing pin 56 mounted in housing 12. At the same time, the transverse movement of wedge 50 causes lead line 54 to become aligned with a detonating cord 58 that leads to line charges 102. Firing pin 56 fires detonator 52 to generate detonation energy which is transported to line charges 102 via lead line 54 and detonating cord 58.
The present invention can also include fuze sterilization to prevent failed or dud systems from existing as an on-going hazard to innocent or retrieval personnel. That is, should some portion of fuze system 10 fail such that wedge 50 does not move at the appropriate time, the fuze sterilization would permanently prevent detonator 52 from being impaled by firing pin 56. By way of illustrative example, fuze sterilization can take the form of water-absorbent fibers (e.g., cotton fibers) compressed into a pellet 60 (or a stack of pellets) mounted in a chamber 62 in housing 12. Ports 64 are provided in housing 12 to lead water to pellet 60 when housing 12 is submerged in water. Pellet 60 is positioned and configured to expand (e.g., axially in the direction of arrow 48) via water absorption to block movement of wedge 50 that might allow detonator 52 to strike firing pin 56. Because the expansion of compressed cotton fibers due to water absorption is relatively slow, pellet 60 can be designed to expand over a period of time that is longer than it should take for fuze system 10 to function properly. Pellet 60 can terminate in a hard tip 66 that shrouds firing pin 56 when pellet 60 expands to further guarantee that firing pin 56 cannot contact detonator 52.
The technical constraint for preventing entrapment of air bubbles in chamber 22 when housing 12 is submerged in water is defined in terms of an L/D ratio where L is the length of chamber 22 in the ready position (FIG. 2) and D is the diameter of piston 24. If the L/D ratio is large, e.g., one or greater, there is a greater chance of entrapping air bubbles in chamber 22 than if the L/D ratio is less than one. The L/D ratio used in successful tests of the present invention was approximately 0.375.
If housing 12 is surrounded by a compressible fluid (e.g., air) while in its ready state shown in FIG. 2, piston 26 will not be driven along bore 16 when lock and release mechanism 32 is disengaged from piston rod 30. This is because air is compressible and because the volume of chamber 22 is large enough to hold the pressurized air even when piston 24 has fully transitioned from the ready position (FIG. 2) to the at-rest position (FIG. 4).
The advantages of the present invention are numerous. The fuze system is fully mechanical and therefore presents no safety concerns for the assembly, storage and usage thereof. In addition, the fuze system is not readied for operation until launch and only permits detonation when submerged in water.
As illustrated, fuze system 10 is constructed for reliable use in harsh environmental conditions where the air is 0° F. or less while the water (e.g., seawater) temperature is at or close to its freezing point, i.e., typically on the order of 27-29°F. In order to prevent the formation of ice in bore 14 or on piston 24, materials used for at least housing 12 and piston 24 should have a low thermal conductivity. Piston 26 and piston rod 30 could also be made of the same material as illustrated. For purpose of the present invention, low thermal conductivity is defined as a material that does not support the formation of ice thereon when cooled to a sub-freezing temperature prior to submergence in freezing seawater. Suitable materials are a variety of plastics such as acetal which is a thermoplastic material with inherent lubricating qualities. Acetal is manufactured by DuPont de Nemours, E. I. and Co. under the trademark Delrin. Materials such as these possess thermal conductivities that are approximately 100 times less than the thermal conductivities of most metals which are susceptible to having ice form thereon when subjected to the conditions described above.
Although the invention has been described relative to a specific embodiment thereof, there are numerous variations and modifications that will be readily apparent to those skilled in the art in light of the above teachings. For example, piston 26 and wedge 50 could be directly coupled to one another and incorporate fuze sterilization as shown in FIGS. 5A and 5B where piston 260 replaces piston 26 and wedge 500 replaces wedge 50. Common elements are referenced with the same numerals as the embodiment illustrated in FIGS. 1-4. Structurally, piston 260 is circularly-shaped at end face 262 opposing piston 24. Piston 260 is hollow along the remainder of its length to define a longitudinal sleeve 264. Fitted in sleeve 264 adjacent end face 262 is a water-absorbent fiber (e.g., cotton) pellet 266. Ports 268 feed through end face 262 to couple chamber 22 with pellet 266. A slot 270 is formed through sleeve 264 in the other end of piston 260. A slide pin 502 mounted on wedge 500 fits in slot 270.
In operation of this embodiment, when water fills chamber 22, water is also admitted through ports 268 to pellet 266 causing pellet 266 to slowly expand axially along sleeve 264. If all parts of the fuze system function properly, water in chamber 22 is pressurized by piston 24 and piston 260 moves to the right before pellet 266 can expand. Rightward movement of piston 260 causes wedge 500 to move upward as pin 502 slides in slot 270. However, if some part of the fuze system fails so that piston 24 does not pressurize the water in chamber 22 in the prescribed timely fashion, pellet 266 expands axially and will eventually press against wedge 500 to prevent any rightward movement of piston 260. The advantages of this embodiment include the direct coupling of piston 260 and wedge 500 as well as the compact way fuze sterilization is incorporated therein.
As mentioned above, other forms of safety restraint can be provided to cooperate with piston 26. On such alternative is illustrated in FIGS. 6A-6C. Structurally, piston 24 is provided with a locking flange 25 that is attached to or integral with piston 24. Flange 25 extends through chamber 22 and into a recess 13 of housing 12 that is parallel to bore 16. Flange 25 should be capable of slight flexing movement in the radial direction of piston 24 for reasons that will become apparent below. Flange 25 has an oblique angle notch 25A formed therein that faces towards piston 26. A sleeve 15 is formed in housing 12 to couple recess 13 with bore 16. Housed in sleeve 15 is a lock ball 17. Finally, piston 26 is notched at 26B to receive lock ball 17 in both the at-rest (FIG. 6A) and readied (FIG. 6B) states as will now be explained.
In FIG. 6A, the fuze system is at-rest so that chamber 22 is sealed and flange 25 is positioned to press lock ball 17 into notch 26B thereby positively restraining piston 26. When the fuze system is readied as illustrated in FIG. 6B, flange 25 still presses lock ball 17 into notch 26B. Note that even though oblique angle notch 25A momentarily passes over lock ball 17, three is no spring-loading on lock ball 17 that would cause same to move radially outward. In FIG. 6C, piston 24 has been released with water in chamber 22. Pressure on piston 26 builds and rightward movement thereof is possible as soon as oblique angle notch 25A is aligned over sleeve 15. That is, the tendency of piston 26 to move right presses lock ball 17 radially outward as illustrated.
In light of the above description, it will therefore be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described. | An air-safed underwater fuze system is provided for munitions that are to launch-deployed and water-detonated. A housing defines a first bore contiguous with a second bore. Radial ports in the housing communicate with the first bore. A first piston is slidably mounted in the first bore and a second piston is slidably mounted in the second bore and positioned flush with the first bore. Piston control means are coupled between the munitions and first piston for positioning the first piston in a first position prior to launch in which the first piston seals off the radial ports while being spaced apart from the second piston to define a chamber. The piston control means moves the first piston at launch to a second position so that the chamber expands and the radial ports are in communication with the chamber. The piston control means further drives the first piston from its second position towards its first position at a specified time after launch. Once the first piston seals off the radial ports, the first piston pressurizes the water in the chamber. As a result, the second piston is driven along the second bore as actuating movement. A firing mechanism is provided in communication with the second bore and coupled to the munitions. The firing mechanism is responsive to the actuating movement of the second piston to generate detonation energy for the munitions. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority to Korean Patent Application Number 10-2010-0123777 filed Dec. 6, 2010, the entire contents of which application is incorporated herein for all purposes by this reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a motor driven column apparatus, and more particularly, to a unique motor type motor driven column apparatus using one unified motor to implement tilt and telescoping motions.
2. Description of Related Art
In general, motor driven power steering (MDPS) systems which are motor driven steering systems are a type which does not use fluid pressure and assists steering power with motor power, and are mainly applied to compact vehicles.
An MDPS system has a decelerator including a worm shaft and a worm wheel rotating by a motor in order to assist the steering power, and uses a motor driven column apparatus having a tilt motor and a telescoping motor to implement tilt and telescoping motions, respectively.
An MDPS motor is controlled by an MDPS ECU, and the tilt motor and the telescoping motor are controlled by a separate tilt/telescoping ECU.
As importance of improvement of fuel efficiency of vehicles is emphasized, there is a trend in that the MDPS systems should be necessarily applied to not only compact vehicles but also mid-size and full-size vehicles.
FIG. 8 shows a motor driven column apparatus having an MDPS motor, a tilt motor, a telescoping motor, and an MDPS ECU and a tilt/telescoping ECU for controlling those motors as described above.
As shown in FIG. 8 , the motor driven column apparatus has an MDPS motor 200 and a decelerator for assisting steering power provided in a column tube 100 covering a steering shaft 100 a , a tilt mechanism for tilting column tube 100 up and down, and a telescoping mechanism for telescoping transmission.
The tilt mechanism includes a tilt motor 300 which is a power source, a deceleration gear 301 decelerating the rotation of the motor and increasing torque, and a tilt rod 302 moving a tilt bracket 303 by an output of deceleration gear 301 .
The telescoping mechanism includes a telescoping motor 400 which is a power source, a deceleration gear 401 decelerating the rotation of the motor and increasing torque, and a telescoping rod 402 moving a telescoping bracket 403 by an output of deceleration gear 401 .
Also, an MDPS ECU 210 for controlling MDPS motor 200 and a tilt/telescoping ECU 500 for controlling tilt motor 300 and telescoping motor 400 are provided, respectively. MDPS ECU 210 is configured to receive a signal of an MDPS motor/angle sensor, and tilt/telescoping ECU 500 is configured to receive signals of a tilt motor/angle sensor and a telescoping motor/angle sensor.
However, since the tilt mechanism having MDPS motor 200 for assisting the steering power and the tilt mechanism having tilt motor 300 and the telescoping mechanism having telescoping motor 400 are separately provided to the motor driven column apparatus as described above, a structure for tilt and telescoping operations is complex, and especially, when the motor driven column apparatus is installed together with a knee airbag, a column collision absorption structure, etc., it is very difficult to secure a package.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
BRIEF SUMMARY
Various aspects of the present invention are directed to providing a unique motor type motor driven column apparatus which uses one unified motor as a power source to implement tilt and telescoping motions, thereby simplifying a tilt and telescoping structure and making it easy to ensure a package of a knee airbag, a column collision absorption structure, etc.
In an aspect of the present invention, the unique motor type motor driven column apparatus, may include a motor attached to a telescoping tube that slidably receives a column tube therein, wherein the telescoping tube may be pivotally coupled with a vehicle body by a tilt bracket, an actuating rod rotating by the motor, a tilt mechanism including a tilt clutch receiving the actuating rod therethrough and selectively engaged therebetween by a motor controller such that a rotation force of the actuating rod may be converted into a linear movement of the tilt mechanism so as to make a tilt motion of the column tube, and a telescoping mechanism including a telescoping clutch receiving the actuating rod therethrough and selectively engaged therebetween by the motor controller such that a rotation force of the actuating rod may be converted into a linear movement of the telescoping mechanism so as to make a telescoping motion of the column tube.
The tilt mechanism may further include a first block housing, and a first moving block operably mounted in the first block housing with a predetermined gap therebetween so that the actuating rod passes through and may be engaged with the first moving block, and wherein the first moving block may include a first groove formed on an outer surface thereof.
The tilt clutch may include a plug rod which may be selectively engaged with the first groove through an opening formed in the first block housing by the motor controller.
The tilt bracket may be pivotally coupled with the first block housing and the vehicle body.
A tilt sensor may include a moving knob fixed to the first block housing, and a potentiometer installed in the telescoping tube at a position of the moving knob to sense a position change of the moving knob according to the tilt motion so as to signal tilting amount to the motor controller.
The telescoping mechanism further may include a second block housing, and a second moving block operably mounted in the second block housing with a predetermined gap therebetween so that the actuating rod passes through and may be engaged with the second moving block, and wherein the second moving block may include a second groove formed on an outer surface thereof.
The telescoping clutch may include a plug rod which may be selectively engaged with the second groove through an opening formed in the second block housing.
The telescoping mechanism further may include a telescoping rod, an end of which may be attached to the second block housing and the other end of which may be attached to a support bracket coupled to the column tube.
A telescoping sensor may include a moving knob fixed to the second block housing, and a potentiometer installed in the telescoping tube at a position of the moving knob to sense a position change of the moving knob according to the telescoping motion so as to signal telescoping amount to the motor controller.
The motor driven column apparatus according to the exemplary embodiment of the present invention uses a unified motor as a power source for implementing tilt and telescoping motions. Therefore, it is possible to simplify a tilt and telescoping structure and make it easy to ensure a package of a knee airbag, a column collision absorption structure, etc.
The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view illustrating a configuration of a unique motor type motor driven column apparatus according to an exemplary embodiment of the present invention.
FIGS. 2A and 2B are views illustrating configurations of tilt and telescoping clutches of the unique motor type motor driven column apparatus according to the exemplary embodiment of the present invention.
FIGS. 3A and 3B are views illustrating configurations of potentiometers of the unique motor type motor driven column apparatus according to the exemplary embodiment of the present invention.
FIGS. 4 and 5 are views illustrating tilt operations of the unique motor type motor driven column apparatus according to the exemplary embodiment of the present invention.
FIGS. 6 and 7 are views illustrating telescoping operations of the unique motor type motor driven column apparatus according to the exemplary embodiment of the present invention.
FIG. 8 is a view illustrating a configuration of a motor driven column apparatus having an MDPS motor, a tilt motor, and a telescoping motor, and an MDPS ECU and a tilt/telescoping ECU for controlling the motors according to the related art.
It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.
In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.
DETAILED DESCRIPTION
Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.
Hereinafter, an exemplary embodiment of the present invention will be described in detail with reference to the accompanying illustrative drawings. The exemplary embodiment is an example and may be implemented in various different forms by those skilled in the art. Therefore, the present invention is not limited to the exemplary embodiment to be described here.
FIG. 1 is a view illustrating a configuration of a unique motor type motor driven column apparatus according to an exemplary embodiment of the present invention. Referring to FIG. 1 , the motor driven column apparatus includes a column tube 1 joined with a mounting bracket 2 mounted to a vehicle body 800 and covering a steering shaft 1 a , an MDPS motor 3 controlled by an MDPS motor ECU 3 a and installed in column tube 1 , a unified motor 5 controlled by a unified motor ECU 4 , generating power for tilt and telescoping motions of steering shaft 1 a , and installed in telescoping tube 30 , a decelerator 6 decelerating the rotation of unified motor 5 and increasing a torque output, and an actuating rod 7 aligned along an axis direction of column tube 1 and rotating by decelerator 6 .
Decelerator 6 and actuating rod 7 are connected to each other as a screw and nut structure for decelerating the rotation of unified motor 5 .
Actuating rod 7 has a thread formed on the outer circumference surface along the overall length.
Actuating rod 7 is supported at one or more positions. To this end, a rod support end 31 integrally formed with a telescoping tube 30 covering column tube 1 supports the middle portion of actuating rod 7 .
The motor driven column apparatus further includes a tilt mechanism 10 engaged with actuating rod 7 to implement a tilt motion by a linear movement of actuating rod 7 , a telescoping mechanism 20 engaged with actuating rod 7 inside tilt mechanism 10 to implement a telescoping motion by rotation of actuating rod 7 , and a tilt sensor 40 and a telescoping sensor 50 sensing a motion of tilt mechanism 10 and a motion of telescoping mechanism 20 and transmitting signals to unified motor ECU 4 .
FIGS. 2A and 2B show internal configurations of clutches of the tilt and telescoping mechanisms according to the exemplary embodiment of the present invention. As shown in FIG. 2A , tilt mechanism 10 includes a tilt clutch 11 , a block housing 13 , a moving block 14 , and a tilt bracket 18 .
Tilt clutch 11 has a plug rod 12 controlled by unified motor ECU 4 to be drawn from and into tilt clutch 11 . In an exemplary embodiment of the present invention, the tilt clutch 11 may be an electromagnetic actuator or pneumatic actuator but limited thereto so as to move the plug rod 12 as generally known in the art.
Actuating rod 7 passes through block housing 13 , and block housing 13 has an opening 13 a from and into which plug rod 12 of tilt clutch 11 is drawn. Moving block 14 is accommodated in block housing 13 with a predetermined gap therebetween and is locked by or released from plug rod 12 . Actuating rod 7 is coupled with moving block 14 in a screw-coupling manner, and passes through moving block 14 . Tilt bracket 18 is connected from block housing 13 to mounting bracket 2 to tilt column tube 1 .
If moving block 14 is not locked by plug rod 12 of tilt clutch 11 , moving block 14 rotates idle with actuating rod 7 at the same place since the moving block 14 is spaced with the block housing 13 with a gap. If moving block 14 is locked with the actuating rod 7 by plug rod 12 of tilt clutch 11 being positioned into a groove 140 formed along outer surface of the moving block 14 , moving block 14 linearly moves by actuating rod 7 .
A tilt motion is implemented by the above-mentioned linear movement of moving block 14 .
Also, inside block housing 13 , a pair of inner rings 15 and 16 is positioned on both sides (i.e. left and right) of moving block 14 . Outside block housing 13 , an outer ring 17 is positioned.
As shown in FIG. 3A , a lower end portion of tilt bracket 18 is linked with block housing 13 by a lower end hinge shaft 19 a , and an upper end portion of tilt bracket 18 is linked with mounting bracket 2 by an upper end hinge shaft 19 b.
As described above, tilt bracket 18 forms a two-point hinge structure, such that, during tilt, the lower end portion of tilt bracket 18 linked by lower end hinge shaft 19 a is pushed aside and rotates. In this case, upper end hinge shaft 19 b acts as a rotation shaft for tilt bracket 18 .
Therefore, tilt bracket 18 can tilt column tube 1 by the movement of the lower end portion linked by lower end hinge shaft 19 a without a movement of the upper end portion linked by upper end hinge shaft 19 b.
Tilting column tube 1 up is implemented by a counterclockwise rotation of tilt bracket 18 , and tilting column tube 1 down is implemented by a clockwise rotation of tilt bracket 18 .
Telescoping mechanism 20 shown in FIG. 2B includes a telescoping clutch 21 , a block housing 23 , a moving block 24 , a telescoping rod 28 , and telescoping tube 30 . Telescoping clutch 21 has a plug rod 22 controlled by unified motor ECU 4 to be drawn from and into telescoping clutch 21 .
In an exemplary embodiment of the present invention, the telescoping clutch 21 may be an electromagnetic actuator pneumatic actuator but limited thereto so as to move the plug rod 22 as generally known in the art.
Actuating rod 7 passes through block housing 23 , and block housing 23 has an opening 23 a from and into which plug rod 22 of telescoping clutch 21 is drawn. Moving block 24 is accommodated in block housing 23 and is locked or released by plug rod 22 . Actuating rod 7 is coupled with moving block 24 in a screw-coupling manner, and passes through moving block 24 . Telescoping rod 28 is fixed to block housing 23 and guides the movement of support bracket 8 to which the telescoping rod 28 is connected, wherein the support bracket 8 is joined with column tube 1 . Telescoping tube 30 is fixed to block housing 23 to be capable of a telescoping movement and covers column tube 1 .
If moving block 24 is not locked by plug rod 22 of telescoping clutch 21 , moving block 24 rotates idle with actuating rod 7 at the same place since the moving block 24 is spaced with the block housing 23 with a gap. If moving block 24 is locked with actuating rod 7 by plug rod 22 of telescoping clutch 21 being positioned into a groove 240 formed along outer surface of the moving block 24 , moving block 24 linearly moves by the actuating rod 7 .
The telescoping motion is implemented by the above-mentioned linear movement of moving block 24 .
Also, inside block housing 23 , a pair of inner rings 25 and 26 is positioned on both sides (i.e. left and right) of moving block 24 . Outside block housing 23 , an outer ring 27 is positioned.
In the exemplary embodiment, as described above, telescoping tube 30 is integrally formed with rod support end 31 supporting the middle portion of actuating rod 7 .
FIGS. 3A and 3B are views illustrating configurations of tilt and telescoping sensors of the unique motor type motor driven column apparatus according to the exemplary embodiment of the present invention. As shown in FIG. 3A , tilt sensor 40 includes a moving knob 41 fixed to block housing 13 in perpendicular to block housing 13 inside tilt bracket 18 to follow the tilt motion, and a potentiometer 42 horizontally installed at the position of moving knob 41 to sense a position change of moving knob 41 according to the tilt motion.
In the exemplary embodiment, as described above, tilt sensor 40 transmits a signal based on the sensed tilt motion to unified motor ECU 4 .
As shown in FIG. 3B , telescoping sensor 50 includes a moving knob 51 fixed to block housing 23 in perpendicular to block housing 23 to follow the telescoping motion, and a potentiometer 52 horizontally installed at the position of moving knob 51 to sense a position change of moving knob 51 according to the telescoping motion.
In the exemplary embodiment, as described above, telescoping sensor 50 transmits a signal based on the sensed telescoping motion to unified motor ECU 4 .
FIG. 4 shows a tilt operation state of the unique motor type motor driven column apparatus according to the exemplary embodiment of the present invention. If a tilt motion is implemented, the rotation of unified motor 5 driven by the control of unified motor ECU 4 is decelerated by decelerator 6 and is converted into a motion for moving actuating rod 7 forward (in a case of tilting column tube 1 up) while rotating actuating rod 7 .
At the same time, unified motor ECU 4 differently controls tilt clutch 11 of tilt mechanism 10 and telescoping clutch 21 of telescoping mechanism 20 , such that the tilt motion can be implemented by the operation of tilt mechanism 10 without interference of telescoping mechanism 20 .
That is, during tilt, unified motor ECU 4 draws plug rod 12 of tilt clutch 11 into opening 13 a of block housing 13 while drawing out plug rod 22 of telescoping clutch 21 from opening 23 a of block housing 23 .
Therefore, moving block 14 of tilt mechanism 10 is locked by plug rod 12 (a locked state Ka), while moving block 24 of telescoping mechanism 20 is released from plug rod 22 (a released state Kb), such that moving block 14 of tilt mechanism 10 moves forward along actuating rod 7 without rotating, while moving block 24 of telescoping mechanism 20 rotates idle at the same place without moving forward along actuating rod 7 .
If moving block 14 of tilt mechanism 10 moves forward as described above, the forward movement force of moving block 14 is converted into a force for pushing block housing 13 through inner ring 16 .
That is, if the tilt motion is implemented, moving block 14 of tilt mechanism 10 moves forward along actuating rod 7 moving forward while rotating so as to push block housing 13 . As block housing 13 is pushed, tilt bracket 18 moves up while rotating so as to tilt column tube 1 up.
The motion of tilt bracket 18 for tilting column tube 1 up is implemented by an action of lower end hinge shaft 19 a and upper end hinge shaft 19 b forming the two-point hinge structure of tilt bracket 18 .
That is, if tilt bracket 18 receives a pushing force by block housing 13 , the lower end portion of tilt bracket 18 linked by lower end hinge shaft 19 a is pushed while rotating. In this case, the upper end portion of tilt bracket 18 linked by upper end hinge shaft 19 b acts as the rotation shaft of tilt bracket 18 . As a result, tilt bracket 18 tilts column tube 1 up by the movement of the lower end portion without the movement of the upper end portion.
In the exemplary embodiment, if unified motor 5 reversely rotates by unified motor ECU 4 (when the rotation direction of unified motor 5 for titling column tube 1 up is referred to as a normal direction), actuating rod 7 moves backward while reversely rotating, such that tilt bracket 18 clockwise rotates so as to tilt column tube 1 down. That is, an operation process for tilting column tube 1 down is the same as the above-mentioned operation process for tilting column tube 1 up, except for the operation directions of the components.
FIG. 5 shows an operation state for detecting the tilt motion during tilt according to the exemplary embodiment of the present invention. If the tilt motion is implemented, in tilt mechanism 10 , block housing 13 is pushed or pulled by moving block 14 to push or pull tilt bracket 18 . The motion of block housing 13 moves moving knob 41 , fixed to block housing 13 in perpendicular thereto, in the same direction as block housing 13 .
The motion of moving knob 41 causes a position change of moving knob 41 relative to potentiometer 42 , and potentiometer 42 transmits an electric signal corresponding to the position change of moving knob 41 to unified motor ECU 4 .
Therefore, unified motor ECU 4 can exactly recognize the progression degree of the tilt motion, and thus, unified motor ECU 4 can greatly improve the accuracy of the tilt motion.
FIG. 6 shows a telescoping operation state of the unique motor type motor driven column apparatus according to the exemplary embodiment of the present invention. If the telescoping motion is implemented, the rotation of unified motor 5 driven by the control of unified motor ECU 4 is decelerated by decelerator 6 and then is converted into a motion for moving actuating rod 7 forward (assuming a case of performing forward telescoping) while rotating actuating rod 7 .
At the same time, unified motor ECU 4 differently controls tilt clutch 11 of tilt mechanism 10 and telescoping clutch 21 of telescoping mechanism 20 , such that the telescoping motion can be implemented by the operation of telescoping mechanism 20 without interference of tilt mechanism 10 .
That is, during telescoping, unified motor ECU 4 draws out plug rod 12 of tilt clutch 11 from opening 13 a of block housing 13 while drawing plug rod 22 of telescoping clutch 21 into opening 23 a of block housing 23 .
Therefore, moving block 24 of telescoping mechanism 20 is locked by plug rod 22 (locked state Kc), while moving block 14 of tilt mechanism 10 is released from plug rod 12 (released state Kd), such that moving block 24 of telescoping mechanism 20 moves forward along actuating rod 7 without rotating, while moving block 14 of tilt mechanism 10 rotates idle at the same place without moving forward along actuating rod 7 .
If moving block 24 of telescoping mechanism 20 moves forward as described above, the forward movement force of moving block 24 is converted into a force for pushing block housing 23 through inner ring 26 .
That is, if the telescoping motion is implemented, moving block 24 of telescoping mechanism 20 moves forward along actuating rod 7 moving forward while rotating so as to push block housing 23 . As a result, block housing 23 pushes telescoping rod 28 and thereby moving the support bracket 8 joined with column tube 1 .
Telescoping tube 30 pushes column tube 1 covered by telescoping tube 30 while being pushed as described above so as to implement forward telescoping to make a steering wheel closer to a driver side.
At this time, tilt mechanism 10 does not make any tilt motion according to the forward movement of actuating rod 7 as described above.
In the exemplary embodiment, if unified motor 5 reversely rotates by unified motor ECU 4 (when the rotation direction of unified motor 5 for forward telescoping is referred to as a normal direction), actuating rod 7 moves backward while reversely rotating, such that telescoping rod 28 is pulled so as to implement backward telescoping. That is, an operation process for backward telescoping is the same as the above-mentioned operation process for forward telescoping, except for the operation directions of the components.
FIG. 7 shows an operation state for detecting the telescoping motion during telescoping according to the exemplary embodiment of the present invention. If the telescoping motion is implemented, in telescoping mechanism 20 , block housing 23 is pushed or pulled by moving block 24 to push or pull telescoping rod 28 . The motion of block housing 23 moves moving knob 51 , fixed to block housing 23 in perpendicular thereto, in the same direction as block housing 23 .
The motion of moving knob 51 causes a position change of moving knob 51 relative to potentiometer 52 , and potentiometer 52 transmits an electric signal corresponding to the position change of moving knob 51 to unified motor ECU 4 .
Therefore, unified motor ECU 4 can exactly recognize the progression degree of the telescoping motion, and thus, unified motor ECU 4 can greatly improve the accuracy of the telescoping motion.
As described above, the motor driven column apparatus according to the exemplary embodiment includes tilt mechanism 10 having tilt clutch 11 converting the rotation force of actuating rod 7 moving by one unified motor 5 into a linear movement force for the tilt motion, and telescoping mechanism 20 having telescoping clutch 21 converting the rotation force of actuating rod 7 into a linear movement force for the telescoping motion. Therefore, the simple configuration with one unified motor 5 makes it easy to secure a package of a knee airbag, a column collision absorption structure, etc.
Further, the motor driven column apparatus according to the exemplary embodiment further includes potentiometers 42 and 52 sensing the tilt motion and the telescoping motion and transmitting the electric signals to unified motor ECU 4 . Therefore, the accuracy of the tilt and telescoping motions is greatly improved, and the reliability is also greatly improved.
For convenience in explanation and accurate definition in the appended claims, the terms “upper”, “lower”, “inner” and “outer” are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.
The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents. | A unique motor type motor driven column apparatus may include a motor attached to a telescoping tube that slidably receives a column tube therein, wherein the telescoping tube may be pivotally coupled with a vehicle body by a tilt bracket, an actuating rod rotating by the motor, a tilt mechanism including a tilt clutch receiving the actuating rod therethrough and selectively engaged therebetween by a motor controller such that a rotation force of the actuating rod may be converted into a linear movement of the tilt mechanism to make a tilt motion of the column tube, and a telescoping mechanism including a telescoping clutch receiving the actuating rod therethrough and selectively engaged therebetween by the motor controller such that a rotation force of the actuating rod may be converted into a linear movement of the telescoping mechanism so as to make a telescoping motion of the column tube. | 1 |
BACKGROUND OF THE INVENTION
The installation of a glazing product, such as a sheet of glass, a sheet of plastic, a ventilator and the like in an opening typically involves the use of a plurality of framing members for supporting the glazing product about its edges. The term glazing product, as commonly used in the glazing industry and as used herein, means any product which is installed in a frame erected in a wall opening or the like. The terms "glazed window" or "window", as used herein unless otherwise indicated from the context, means an assembly comprising a glazing product glazed in a frame. which is supported about its edges by a plurality of framing members or they may comprise two or more sheets of glazing product, in which case there is further provided a framing member called a mullion for joining the sheets.
The installation or erection of windows may take several forms depending on the particular type of windows, the number and arrangement of the windows and the nature of the opening in which they are erected. In one type of erection, a part of the framing members used for supporting the windows is installed in the opening. The glazing product is then inserted and a glazing stop attached for retaining the glazing product in the frame. Caulking, putty or other sealants are then inserted between the framing members and the glazing product to seal the window against the weather.
The erection of windows in the manner just described is time-consuming and costly because of the labor involved. This is particularly true in the erection of windows in high-rise buildings because of the precautions that must be taken in transporting unsupported glass sheets.
Principally for these reasons, the glazing industry has turned to a more efficient method of erecting windows in which the windows are factory glazed. That is, the glazing products are glazed in their framing members before being taken to the jot site. Once at the job site, they are installed over a pre-installed sub-framing member or otherwise fixed in a prepared opening.
The present invention is in part related to these types of windows -- that is, to novel window frame assemblies which may be pre-glazed at the factory.
With the advent of new glazing products and because of the aesthetic and beneficial characteristics of windows, windows are being used more frequently in place of steel bars and the like for enclosing openings in security areas, such as prisons, warehouses, and the like.
When used in such applications, it is obviously necessary to prevent entry of the window. This requires not only the use of an unbreakable glazing product but also the employment of means for preventing destruction of the framing members holding the glazing product.
Presently, the most widely used materials for window framing members are aluminum and relatively thin steel. Both of these materials are relatively easy to saw or otherwise cut. Consequently, so far as it appears, others, heretofore, have been dissuaded from attempting to replace barred openings and the like with ordinary appearing, but much more aesthetically pleasing windows on a large scale.
To prevent a successful entry through a window using such framing materials, the present invention employs rotatable rod members in each of the framing members.
The use of rotatable rod members is known to have been proposed long ago for use in prison bars and the like for preventing the successful sawing or cutting thereof, but so far as is known, no one heretofore has suggested their use for preventing the destruction of an otherwise relatively easily destructable window framing member.
SUMMARY OF THE INVENTION
In view of the foregoing, a principal object of the present invention is a novel window frame assembly and method for fabricating pre-glazed windows comprising novel framing members. Another object of the invention is a novel mullion for installing pre-glazed windows. Another object of the present invention is a window frame assembly comprising means for preventing the cutting through of a framing member as by a saw or the like.
In accordance with the above objects, there is provided in one embodiment of the present invention, a window frame assembly having framing members comprising: a T-shaped framing member; a glazing stop with means for attaching said stop to said T-shaped member to form a U-shaped channel for securing a glazing product; and an L-shaped framing member with means for attaching said L-shaped member to said T-shaped member to form a U-shaped channel for securing said framing member to a pre-installed sub-framing member.
In another embodiment of the present invention, rotatable rod means are provided in a framing member for preventing the sawing through of said framing member. In this embodiment, a means is also employed for preventing the non-destructive disassembly of the framing member.
In still other embodiments of the present invention, there is provided a novel mullion means for erecting a pair of pre-glazed windows with and without means for preventing the non-destructive disassembly of said mullion means. In certain ones of these embodiments, a means is optionally provided for the attachment of a partition.
DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present invention will be apparent from the following detailed description of the accompanying drawings in which
FIG. 1 is an elevation view of a single window unit in accordance with the present invention.
FIG. 2 is a cross-sectional view taken along lines 2--2 of FIG. 1.
FIG. 3 is an elevation view of a single window unit in accordance with another embodiment of the present invention.
FIG. 4 is a cross-sectional view taken along lines 4--4 of FIG. 3.
FIG. 4a is a cross-sectional view taken along lines 4a-4a of FIG. 4.
FIG. 4b is a top view of FIG. 4a.
FIG. 5 is a partial elevation view of a double window unit with a mullion in accordance with the present invention.
FIG. 6 is a cross-sectional view taken along lines 6--6 of FIG. 5.
FIG. 7 is a cross-sectional view of an alternative embodiment of the mullion of FIG. 5.
FIG. 8 is a cross-sectional view of another alternative embodiment of the mullion of FIG. 5.
DETAILED DESCRIPTION
The terms "glazing product", while typically used in reference to one or more sheets of glass, are considered in the glazing industry, and are used herein, as referring to any product -- e.g., a sheet of glass, a sheet of plastic or a ventilator assembly -- which is capable of being glazed in a frame. Similarly, the term "window" is considered in the glazing industry, and is used herein, as referring not merely to the glazing product but rather to the entire assembly of glazing product and supporting frame members.
With respect to the following description, it should also be understood that all of the novel framing members of the present invention need not necessarily be identical in any given installation but that, depending on the application, one or more of the members in a given installation may be constructed somewhat differently. For example, the header and jamb framing members may be identical in cross-section, while the sill framing member is constructed for attachment using sill clips and the like. Such features are considered conventional and form no part of the present invention beyond the fact that they may be used as required with framing members made in accordance with the invention.
Referring to FIGS. 1-2, there is provided in accordance with the present invention a window 1 comprising a glazing product 2 which is supported in a plurality of framing members 3, 4, 5 and 6. For purposes of describing the present invention, each of the framing members 3-6 has an identical cross-section. It is understood, however, that one or more of them may be constructed differently for adaptation to the requirements of a particular installation. Accordingly, only one of the framing members, member 4, need be described.
Referring to FIG. 2, there is provided in framing member 4 a sub-framing member 95. Member 95 typically comprises a U-shaped channel having a base section 96 and a pair of spaced parallel leg members 7 and 8 extending therefrom. For attachment to a jamb, comprising a concrete or wooden surface 9, or the like, there is provided one or more attaching fittings 10 which, depending on the application, may comprise a lag bolt, screw, nut and bolt, or the like. Fittings 10, only one of which is shown, are positioned at pre-selected intervals along the length of the framing member.
Fitted about the sub-framing member 95 is an h-shaped framing member 15. Member 15 has a relatively thick base section 16 from which extend in opposite directions a pair of spaced parallel leg members 17 and 18 and a single leg member 19. Members 17 and 18 form a U-shaped channel for receiving the member 95. Member 19 forms a part of another U-shaped channel for receiving the glazing product 2. To reduce weight and conserve material, the interior surfaces of leg members 17 and 18 are provided with a plurality of parallel extending grooves or recesses 14, 14 . . . .
Spaced from leg member 19 and attached to section 16 of member 15 as by a screw 20 is a U-shaped glazing stop 21. Stop 21 has a base section 22 from which extend a pair of spaced parallel leg members 23 and 24. Leg member 24 is provided with an extended section 11 and is, therefore, somewhat longer than member 23 such that it is substantially coextensive with member 19. The U-shaped channel thus formed between leg members 19 and 24 serves as a receiving space for the glazing product 2.
Mounted at selected locations along the length of framing member 4 in the channel formed by leg members 19 and 24 is one or more block members 25. Each of block members 25 is provided with a hole through which is passed an elongated rotatable rod member 26. The length of the member 26 is preferably substantially equal to the length of the framing member 4. The holes have a diameter slightly larger than the diameter of the rod member so as to allow the rod member to rotate freely therein. The number, size and location of the blocks 25 in each of the framing members 3-6 are chosen such that any expected lateral forces on the rod member 26 are insufficient to bend and bind the rod member by friction in the holes so as to prevent its free rotation. Also, the blocks 26 are preferably formed from a material having a low coefficient of friction and the rod member 26 is formed from a material having the hardness and resistance to cutting as by sawing of tool steel.
The purpose, therefore, of the blocks is to serve as a bearing surface for the rod member 26 such that, if any attempt is made to saw through the framing member 4, the saw, when contacting the rod member 26, will cause the rod member to rotate in the blocks. This is effective to prevent cutting of the rod member. From the foregoing, it follows that, for long lengths of rod, the rod member 26 should be supported at several points so as to prevent its being bent by a saw such that it becomes bound in a block and can then be cut.
To prevent non-destructive dissassembly of the window 1, there is further provided a non-removable cover member 27. Member 27, after the window is installed, is inserted between the legs of stop 21 to cover the screw means 20.
In the cover member 27, there is provided, extending from the interior surfaces thereof, a pair of spaced leg members 28 and 29. Members 28 and 29 are, respectively, terminated by a shouldered clip-like termination 12 and 13 for non-removable engagement with a corresponding pair of engaging surfaces in the surfaces of leg members 23 and 24 of the stop 21. Termination 12 and 13 serves to prevent the non-destructive removal of the cover 27 and, thereby, the non-destructive disassembly of the framing member 4.
To install a window according to the embodiment of FIGS. 1 and 2 in a pre-constructed opening, the sub-framing member 95 and the corresponding member in each of the members 3, 5 and 6 are fitted with a plurality of fittings 10 and inserted between the legs 17 and 18 of the h-shaped member 15. They are temporarily secured there as by masking tape or the like. The member 15, with the member 5 so secured, is then inserted and plumbed in the opening. Through pilot holes (not shown) in the base section 16 of member 15, which are located in registration with the fittings 10, the fittings 10 are then screwed into or otherwise fixed in the header, jambs and sill. The blocks 25 and the rod members 26 are then positioned with the glazing product 2 suppported therebetween. Finally, stop 21 is installed, weather sealing material 97 is added between the glazing product 2 and leg members 19 and 24 and cover 27 is inserted.
Referring to FIGS. 3-4, there is provided in another embodiment of the present invention a window 30. Window 30 comprises a glazing product 2, as described above with respect to FIGS. 1-2, supported in a plurality of framing members 34, 35, 36 and 37. Each of the members 34, 35, 36 and 37 is identical and accordingly only one -- namely, member 34 -- is described.
Referring to FIG. 4, there is provided in the member 34 a number of the features of the member 4 of FIG. 2. As to those members which are identical in both embodiments, the same numerical designators are employed for identification purposes and a reference to the discussion above is invited for the details of their construction. Included in the list of features which are identical in both embodiments are the sub-framing member 5 and fitting 10, the block 25 and rod member 26, and the cover member 27.
In contrast to member 15 of FIG. 2, there are provided in the embodiment of FIG. 5, a main framing member 40 comprising two separable members, a T-shaped framing member 41 and L-shaped framing member 42. Member 41 has a thick base section 43 from which extends from one end thereof a pair of oppositely directed leg members 44 and 45. L-shaped member 42 comprises a pair of perpendicular leg members 46 and 47. In the base section 43, opposite the end from which members 44 and 45 extend, is a recess for recessing the leg 46 of member 42. Attached to the base section 43 by means of a screw means 20 is a glazing stop 48. In stop 48 and in base section 43, in communication with the recess and in registration with each other, is a pilot hole for receiving a screw means 49. Screw means 49 is used for fixedly attaching the leg member 46 in the recess in the base section 43. Because of the pilot hole in the stop 48, however, screw means 49 can be inserted and member 42 secured before stop 48 is attached. As previously described, in all other essential respects, the remaining features of the framing member 40 are identical to the same features in the member 4 of FIGS. 1-2 and reference may be made to the description above for the details with respect to those features.
Referring to FIGS. 5 and 6, there is provided a pair of window units 31, 31 which are joined by a mullion 32 according to the present invention. Windows 31, 31 may comprise the framing members of the embodiments described above except that there is typically a modification to the inside members 38, 38 . . . joined by the mullion.
In the members 38, 38 . . . there is provided an h-shaped main framing member 50 which is similar to the h-shaped member 15 described with respect to FIGS. 1-2. The only essential difference between the two members 50 and 15 is that the pair of parallel leg members 17 and 18 of member 15 are foreshortened in member 50 and terminated by a pair of inwardly directed flanges 51 and 52. In addition, a plurality of sealing members 53, 53 . . . are provided between the framing members 40, 50 . . . for weather sealing. In all other respects, the features of members 50 are identical to those of member 4 of FIG. 2.
In mullion 32 there is provided a pair of L-shaped members 60 and 61. Members 60 and 61 comprise a pair of spaced parallel leg members 62 and 63 and a pair of oppositely directed leg members 64 and 65 which are rigidly attached by a bridging member 71 and a recessed bridging member 66, recessed between the legs 62 and 63. Attached to the bridging member 66 as by a screw means 67 is a face plate 68 comprising a pair of spaced oppositely directed legs or plate members 69 and 70. The space between the plate members 69 and 70 is recessed to fit in the recess provided by the recessed bridge member 66 between the leg members 62 and 63 of the members 60 and 61. As described above with respect to the embodiments of FIGS. 1-4, screw 67 is covered by a cover member 27 which is non-removably inserted in the recess of plate 68 to engage corresponding shouldered surfaces in the interior walls thereof.
Referring to FIG. 7, there is provided a mullion 72 which is an alternative embodiment of the mullion 32 of FIG. 6. In mullion 72, the bridging member 71 of FIG. 6 is omitted. Parallel leg members 62 and 63 are extended by means of a pair of parallel flange members 73 and 74 somewhat beyond the plane of leg members 60 and 61. Attached to flange members 73 and 74 as by rivets or screws 75 and 76, or the like, is an elongated U-shaped channel 77. Channel 77 may be ridigly attached to a partition, wall or the like by means of one or more fittings 78. In all other respects, the mullion 72 is identical to the mullion 32 of FIG. 6.
In FIG. 8, there is shown yet another embodiment of a mullion according to the present invention.
Referring to FIG. 8, there is provided in a mullion 80 an H-shaped framing member 81. Attached to opposite sides of member 81, in the recesses between its parallel legs, as by screw means 82 and 83, are a pair of identical facing plate members 84 and 85. Each of plate members 84 and 85 are identical to facing plate member 68 of FIG. 6 and incorporate cover members 27, as shown in FIG. 6.
In the installation of the windows according to the embodiments of FIGS. 3-8, the sub-framing members 5 are first attached to and plumbed in the sides of a pre-constructed opening in a wall or the like except for that part of the frame contiguous to a mullion. The remainder of the frame, which is preferably pre-glazed, is then inserted and the attachable L-shaped framing member 42 is fitted and tightened in the recess of the T-shaped member 41 by the screw means 49. The glazing stop 21, which is at that time already attached by the screw means 20, is then fitted with the cover 27 to cover the screw means 20 and 49.
With respect to the erection of the mullions of FIGS. 5-8, the installation procedure is equally simple since all that is required, once the mullion is in place, is the attachment of the respective face plates. With respect to the embodiment of FIG. 8, of course, the mullion can be reversed since two opposing attachable face plates are used.
It is apparent from the foregoing that various combinations of the embodiments described may be incorporated in a given installation depending on the requirements of the job. It is also apparent that various modifications can be made to the embodiments described, as required, without departing from the spirit and scope of the present invention. It is, therefore, intended that the embodiments described serve only as illustrations of the present invention and that the true scope of the invention be determined by reference to the claims hereinafter provided. | Several embodiments of window frame assemblies comprising novel window framing members for supporting a glazing product are described. In one embodiment, a window frame assembly is described comprising a conventional framing member including a novel rotatable rod means for preventing the cutting through of the framing member as by a saw. In another embodiment, a window frame assembly is described comprising a framing member for installing pre-glazed windows with or without a rotatable rod means in the framing member, said member including a separately attachable leg member for attaching the pre-glazed window to a pre-installed sub-framing member. In still other embodiments, window frame assemblies are described comprising novel mullions for joining pairs of pre-glazed windows. The mullions, as described, may optionally include means for the attachment of a partition and the aforementioned rotatable rod means. | 4 |
This application is a divisional of, and claims priority to U.S. application Ser. No. 10/250,561 filed October which claims priority to International Application No. PCT/CU01/00014 filed on Dec. 17, 2001. This application also asserts priority to Cuban Application No. CU 2001/0004 filed on Jan. 3, 2001.
FIELD OF THE INVENTION
This invention comprises several synergistic compositions, of the pesticide and antiparasitic kind, useful for the control of parasitic phytonematodes and zoonematodes, some diseases (fungal and bacterial), and the control of parasitic trematodes ( Fasciola hepatica ).
BACKGROUND OF THE INVENTION
Nematodes are blamed for causing the greatest damages to agriculture in tropical, subtropical and temperate regions worldwide (Nickle W. R. (Editor). 1991. Manual of Agricultural Nematology, Marcel Dekker, Inc., New York, N.Y. Pub. 1035 pp). Plantain alone has about 20% nematode-related losses of world production, representing $178 millions each year (Sasser J. N. and Freckman D. W. 1987. A world perspective on nematology: the role of the society. Vistas on nematology: a commemoration of the twenty-fifth anniversary of the Society of Nematologists/edited by Joseph A. Veech and Donald W. Dickson. p. 7-14). Plantain and banana plantations are significantly affected by Radopholus similis.
Meloidogyne spp is the most important plant parasitic nematode, for its activity causes losses between 11% and 25% of crops in almost all the tropical regions (Sasser J. N. 1979 . Root - knot nematodes . Ed. F. Lamberti & C. E. Taylor, Academic Press, London, p 359). Consequently, there is a great need to control those parasites that were fought against with chemical nematicides in the past. Such compounds can be highly effective; however, many of them pose a great danger on the environment. In some cases the regulating authorities have limited the amount or frequency, or both in the use of such compounds, thus compromising their nematicidal effectiveness.
Nematode control still falls short. The use of chemical nematicides is restricted each day more and more, because they have highly toxic and widespread action compounds. As a result, efforts have been made to identify the effective means to eliminate the damage caused by nematodes, in favor of reducing the use of chemical pesticides. One of the approaches is the use, of biological ones with specific mode of actions and relatively safer toxicological profiles, instead of chemical nematicides. Some of the alternative nematicides include ABG-9008, a Myrothecium verrucaria fungus metabolite and a combination of avermectines (or related compounds, like milbecines) with fatty acids (Abercrombie K. D. 1994. Synergistic pesticidal compositions. U.S. Pat. No. 5,346,698. Mycogen Corporation. September. 13). Likewise, a method that includes concurrent administration to eliminate damages caused to plants by nematodes, the site, soil or seeds that need treatment of a) a Myrothecium verrucaria fungus metabolite and b) a chemical pesticide, as well as the synergistic nematicide compositions useful in this case, is claimed under patent (Warrior P., Heiman D. F. and Rehberger Linda A. 1996. Synergistic nematocidal compositions. Abbott laboratories. WO9634529, 1996 Nov. 7). Another approach is to combine spores of Pasteuria penetrans a nematode bacterial parasite, with organophosphorated nematicides (Nordmeyer D. 1987. Synergistic nematocidal compositions of Pasteuria penetrans spores and an organophosphorus nematocide. 1987. CIBA-GEIGY AG Patent AU 06057386A1. Jan. 29, 1987).
However, preparation of P. penetrans spores at industrial scale faces the problem that the organism is an obligated parasite; hence it must be grown in in situ nematodes, isolated from nematode infested root digests.
Chitinolytic fungi and bacteria that share the nematode's habitat, may have certain biological balance and somehow restrict nematode proliferation. Two strains of chitinolytic bacteria (Toda T. and Matsuda H. 1993. Antibacterial, anti-nematode and/or plant-cell activating composition, and chitinolytic microorganisms for producing the same. Toda Biosystem Laboratory, Japan. U.S. Pat. No. 5,208,159, May 4, 1993) have been claimed as antibacterial, antinematode and/or plant-cell activating composition.
There are some examples of the chitinolytic effect on nematodes. Some of the most significant are the strains of new bacteria described (Suslow T. and Jones D. G. 1994. Novel chitinase-producing bacteria and plants. DNA Plant Technology Corporation, U.S. Pat. No. 4,940,840, Jul. 10, 1990) that are created by the introduction of DNA that codifies for chitinase production, an enzyme that can degrade chitin in fungi and nematodes. The strains are useful in the production of chitinase to inhibit plant pathogens. Novel plants resistant to pathogens are described too, as the result of introduction of DNA codifying for chitinase production.
Other instances of microorganisms that reduce nematode populations that attack plants in natural conditions are described.
Rodriguez-Kabana et al. (Rodriguez-Kabana R., Jordan J. W., Hollis J. P. 1965. Nematodes: Biological control in rice fields-role of hydrogen sulfide. Science. 148: 524-26); Hollis and Rodriguez-Kabana (Hollis, J. P., y R. Rodríguez-Kábana. 1966. Rapid kill of nematodes in flooded soil. Phytopathology 56, pp 1015-19) observed correspondence among bacterium Desulfovibrio desulfuricans , hydrogen sulfide production and plant parasitic nematodes, whose population decreased in Louisiana's rice plantations. Sulfides are inhibitors in the electron transport breathing process of the aerobic organism, just like other metabolites produced by certain soil bacteria (Rodríguez-Kábana, R. 1991. Control biológico de nematodos parásitos de plantas. NEMATROPICA, 21(1), pp 111-22).
PAECIL™, also known as BIOACT or Nemachek, is a biological nematicide that contains a patented strain from Paecilomyces lilacinus , in a dry and stable spore concentration for soil and seed treatment. This fungal species is commonly found in all soils worldwide. The patented strain used as PAECIL™ active ingredient has a particular effectiveness against plant parasitic nematodes. It was originally isolated at The Philippines University, and has been developed in Australia, Macquarie University. Furthermore, it has been broadly tested for the control of several kinds of nematodes that attack major crops in Australia, The Philippines, South Africa, and others. PAECIL™ formulation is commercially available as a pesticide registered in The Philippines, under the name of BIOACT®; in South Africa, under the name of PL PLUS; and Indonesia, under the name of PAECIL™. Currently, the Australian National Registration Authority is evaluating the product as a pesticide (Holland, R. PAECIL™. 1998. http://www.ticorp.com.au/article1.htm). The above-mentioned instances fail to solve all parasitic helminth problems. Therefore, the need to implement improved means for parasite control to substitute chemical pesticides and antiparasitic products still remains.
Trematodes cause considerable economic damage to animal production and human health. The diversity of the species, relative benign pathogenicity and endemism in isolated regions seem to be essential factors that effect on the lack of knowledge on trematodes. In general terms, intestinal trematodes are zoonotic and have a large number of reservoir hosts in each species.
Economically speaking, one of the most significant trematodes is Fasciola hepatica , the first known parasitic trematode; it affects man by inhabiting the bile conduits. Its egg is one of the largest, ovoid and operculated from helminthes, and causes digestive malfunction consisting in gastric disepsia, colon motility malfunction, liver and bile vesicle pain, fever and hepatic colic. Other signs may include cystic forms in lungs, eyes, brain, hepatic vein, and other tissues (Saleha A. 1991. Liver fluke disease (fasciolosis) epidemiology, economic impact and public health significance. Southeast Asian J. Trop. Med. Public health 22 supp 1dic. P 361-4)
Zoohelminths have become significant pests to sheep and cattle. Antihelminthic resistance is wide, particularly in populations of small ruminant parasitic nematodes.
New supplementary techniques have been developed, others are under research. Fungus, Duddingtonia flagrans is a predator that forms nets, produce wide wall, motionless spores: clamidospores, able to survive the passage along the intestinal tract of cattle, equines, sheep and swine (Larsen M. 1999. Biological control of helminths. Int J Parasitol . January; 29(1): 139-46, and Larsen, M. 2000. Prospects for controlling animal parasitic nematodes by predacious micro fungi. Parasitology, 120, S120-S121).
Works on D. flagrans in Denmark, France, Australia, USA, and Mexico, have confirmed the strong potential for biological control this fungus has.
Like many other important sheep producing countries, South Africa undergoes a big crisis in terms of antihelminthic resistance, especially in gastrointestinal nematodes in sheep and goat. Significant parasitic helminthes are involved in this phenomenon; however, this causes a particular problem with abomasum hematophage parasite Haemonchus contortus . The studies point out that over 90% of this parasite's strains from the most important sheep producing regions in South Africa, show several drug resistance degrees, in three out of the four antihelminthic groups available in the South African market. Even in areas of common grazing in Northern Province, it was detected in five herds studied in 1993 (van Wyk J. A., Bath G. F. and Malan F. S. 2000. The need for alternative methods to control nematode parasites of ruminant livestock in South Africa. World Animal Review. http://www.fao.org/ag/AGA/AGAP/FRG/FEEDback/War/contents.htm).
Resistance increase has become serious, since it has been experienced in other areas as well. A series of antihelminthic studies have been recently conducted in four Latin American countries: Argentina (Eddi, C., Caracostantogolo, J., Peya, M., Schapiro, J., Marangunich, L., Waller, P. J. & Hansen, J. W. 1996. The prevalence of anthelmintic resistance in nematode parasites of sheep in southern Latin America: Argentina. Vet. Parasitol., 62: 189-197); Brazil (Echevarria F., Borba M. F. S., Pinheiro A. C., Waller P. J. & Hansen J. W. 1996. The prevalence of anthelmintic resistance in nematode parasites of sheep in southern Latin America: Brazil. Vet. Parasitol., 62: 199-206); Paraguay (Maciel S., Giminez A. M., Gaona, C., Waller P. J. & Hansen J. W. 1996. The prevalence of anthelmintic resistance in nematode parasites of sheep in southern Latin America: Paraguay. Vet. Parasitol., 62: 207-212); and Uruguay (Nari A., Salles J., Gil A., Waller P. J. & Hansen J. W. 1996. The prevalence of anthelmintic resistance in nematode parasites of sheep in southern Latin America: Uruguay. Vet. Parasitol., 62: 213-222).
One of the nematodes that causes the greatest damages to cattle is Dictyocaulus viviparous , a parasite that comes to sexual maturity and when adult, is lodged in the lung of cattle, particularly young animals. The diseased caused is known as verminose bronchitis, or bovine Dictyocaulosis, and infestation is produced after ingesting the 3 or infesting larvae, present in the pastures. The treatment requires antihelminthics (Borgsteede F. H. M, de Leeuw W. A. & Burg W. P. J. 1988. A comparison of the efficacy of four different long-acting boluses to prevent infections with Dictyocaulus viviparus in calves. The Veterinary Quarterly, Vol 10, No. 3), but success is at the expense of new strains resistant to the drugs, which make further infested animal treatment harder. The high cost of these products is a restrictive factor to the countries with a large number of resources, and harmful ecological effects are produced with the use of these formulations.
The international problem of anthelmintic resistance is compounded by the fact that, while chemotherapy continues to be the cornerstone of parasite control, there seems little hope that any novel, chemically unrelated anthelmintics will be forthcoming for at least the next decade (Soll, M. D. 1997. The future of anthelmintic therapy from an industry perspective. In J. A. van Wyk & P. C. van Schalkwyk, eds. Managing anthelmintic resistance in endoparasites , p. 1-5. Proceedings of the 16th International Conference of the World Association for the Advancement of Veterinary Parasitology, Sun City, South Africa, 10-15 Aug. 1997).
In the case of bacteria and pathogenic fungi, there are comprehensive reports on biologicals, whose action is mainly based on antagonism and that a large amount of them are commercially available. Some of them are Conquer ( Pseudomonas fluorescens that antagonizes Pseudomonas tolassii ), Galltrol-A ( Agrobacterium radiobacter , that controls Agrobacterium tumefaciens ), Bio-Fungus ( Trichoderma spp, that controls the following fungi: Phytophthora, Rhizoctonia solani, Pythium spp, Fusarium, Verticillium ), Aspire ( Candida oleophila I-182 that controls Botrytis spp. and Penicillium spp), etcetera.
One of the most widely active biofungicides is Trichoderma spp (Chet I, Inbar J. 1994 Biological control of fungal pathogens. Appl Biochem Biotechnol; 48(1):37-43) a fungus whose action mechanism is largely discussed, where chitinases that degrade the cellular wall of the host fungus take part. Moreover, there are experimental evidences of chitinolytic action from fungi and bacteria used as fungal disease bioregulators (Herrera-Estrella A, Chet I. 1999. Chitinases in biological control. EXS; 87:171-84). However, this is not the only mode of action of bacteria over phytopathogenic fungi; there are other control ways based on the production of secondary metabolites, like hydrogen cyanide, that manages to inhibit root pathogenic fungi (Blumer C. and Haas D. 2000. Mechanism, regulation, and ecological role of bacterial cyanide biosynthesis. Arch Microbiol March; 173(3):170-7), in the particular case of P. fluorescens CHAO strain.
Analyses of bacterium-bacterium interaction have shown there are three main types: antibiosis, substrate competition and parasitism. In the case of antibiosis, some bacterial strains are known to release antibiotics in order to suppress the surrounding bacterial activity, which may be used for biological control of pathogenic species. Likewise, substrate competition is a mechanism that may as well be used to achieve proper biological control, since the bioregulating organism is able to synthesize siderophores microelement quelant agents, which causes microelement deficiency, mainly iron, in the medium, thus inhibiting the respective pathogenic growth (Ongena M. 1998. Conference on biological controls. Training program in the area of biotechnology applied to agriculture and bioindustry. Gembloux, Belgium).
SUMMARY OF THE INVENTION
The invention is related with a composition that contains, at least, one chitinolytic agent or a chitinolytic activity inducing agent, and sulfide or a sulfide producing agent from microorganisms or chemical compounds, where the chitinolytic agent or a chitinolytic activity inducing agent, and sulfide or sulfide producing agent from microorganisms or chemical compounds, are concurrently applied at a substantially minor degree than when each component is used independently to achieve effective control over helminths and causative agents of bacterial and fungal diseases.
The invention is also related with the use of such compositions and/or the concurrent administration of the said compounds from different sources, such as, biologicals and chemicals for effective control over a wide spectrum of plant parasitic nematodes ( Meloidogyne spp, Angina spp, Ditylenchus spp, Pratylenchus spp, Heterodera spp, Aphelenchus spp, Radopholus spp, Xiphinema spp, Rotylenchulus spp), animal parasitic nematodes and trematodes ( Haemonchus spp, Trichostrongylus spp, Dictyocaulus spp. y Fasciola hepatica ), bacterial agents causative of diseases ( Erwinia chrysanthemi, Burkholderia glumae ) and fungal agents causative of diseases ( Pestalotia palmarum, Alternaria tabacina, Sarocladium orizae ).
DETAILED DESCRIPTION OF THE INVENTION
The effects of a chitinolytic agent or a chitinolytic activity inducing agent and sulfide, or a sulfide-producing agent on helminths, bacteria and fungi have been previously demonstrated or reported. In this study, however, for the first time, a synergistic effect is demonstrated when both components are concurrently applied.
When the chitinolytic agent, or the chitinolytic activity inducing agent and sulfide or a sulfide producing agent are separately applied, the effects are always less than when the two agents are simultaneously applied.
When applied as a composition of the present invention, the chitinolytic agent or the chitinolytic activity inducing agent and sulfide, or sulfide producing agent can be appropriately mixed in the form of a solution, suspension, emulsion, powder or granulating mixture, and is applied to the plant or soil as a fertilizer, pre-packed soil, covert seed device, a powder, granulate, nebulizer, a suspension, liquid, or any of the indicated form in capsules for the control of parasitic helmiths, and bacterial and fungal diseases.
The optimal application ranges of the chitinolytic agent or the chitinolytic activity inducing agent and sulfide or a sulfide producing agent for the particular case of nematodes, trematodes, bacteria or fungus; and for the case of specific conditions, the ranges are determined through experimental studies, in vitro, greenhouse or under field conditions.
According to the results described in the present invention, a significant control over helminths, bacteria and fungi is achieved with a mixture of 1) a chitinase producing microorganism between 10 7 Colony Forming Units (CFU) and 10 12 CFU of a particular microorganism per composition gram or chitin between 1% and 50% of the composition; and 2) a sulfide producing microorganism between 10 7 CFU and 10 12 CFU of a particular microorganism per composition gram, or any sulfide producing chemical agent, where sulfide varies between 1.0 mg/minute per composition gram.
Any composition with a microorganism between 10 7 CFU and 10 12 CFU per composition gram, that concurrently produces chitinolytic agents and sulfide, is appropriate for the control over helminths, bacteria and fungi. The previous compositions involve combinations of the following agents in the above-mentioned proportions:
1. Chitinase and Na 2 S.
2. Chitinase and FeS.
3. Chitinase and microorganism Desulfovibrio desulfuricans.
4. Chitinase and Na 2 S.
5. Chitinase and FeS.
6. Chitine and microorganism Desulfovibrio desulfuricans.
7. Microorganism that produces chitinolytic activity and H 2 S concurrently.
The previous compositions are effective against a wide range of plant parasitic nematodes, including, not limiting Meloidogyne species, such as, M. incognita; Angina species, such as A. tritici; Ditylencus species, such as D. dipsaci; Pratylenchus species, such as P. coffee; Heterodera species, such as H. glycines; Aphelenchus species, such as A. avenae; Radopholus species, such as R. similis; Xiphinema species, such as X. index; Rotylenchulus species, such as R. reniformis ; zoonematodes such as: Haemonchus spp, Trichostrongylus spp, Ostertagia spp, Nematodirus spp, Cooperia spp, Ascaris spp, Bunostomum spp, Oesophagostomum spp, Chabertia spp, Trichuris spp, Strongylus spp, Trichonema spp., Dictyocaulus spp., Capillaria spp., Heterakis spp., Toxocara spp, Ascaridia spp, Oxyuris spp, Ancylostoma spp, Uncinaria spp, Toxascaris spp and Parascaris spp; trematodes, such as Fasciola hepatica ; plant pathogenic bacteria, such as Erwinia chrysanthemi, Burkholderia glumae , and plant pathogenic fungi such as Pestalotia palmarum, Alternaria tabacina and Sarocladium orizae.
EXAMPLES
Example 1
In Vitro Evaluation of the Nematicidal Effect of Hydrogen Sulfide from Chemical Sources and a Chitinolytic Enzyme
Eggs from zoonematodes Haemonchus spp and Trichostrongylus colubriformis and Dictyocaulus viviparus were used, as well as parasitic phytonematode larvae (juveniles 2) from Melodoigyne incognita.
Collections of Haemonchus spp and Trichostrongylus colubriformis nematodes were made from ovine (sheep) and bovine (cattle) abomasa, respectively. The adult female nematodes were washed in a physiological solution and treated with “Hibitane” (Chlorhexidine Acetate) at 0.5%, for 1 minute, the process developed at 37° C. Approximately 100 previously disinfected individuals were introduced into an Erlenmeyer containing 50 ml of LB medium solution, diluted 10 times in distilled sterile water, and were left laying their eggs overnight (8-10 hours).
Collections of D. viviparous nematode were made from the infested lung of a bovine (cattle), previously sacrificed. The same procedure was used for Haemochus spp. and T. colubriformis ; however, the females were allowed to lay their eggs for 2-3 hours.
From that moment on, manipulation was done under aseptic conditions in a vertical laminar flow, using 24-well tissue culture plates. The total volume of the medium that contained the females and the eggs was filtered with a sift net of 60 μm. The nematode eggs were trapped on the 30 μm net of a second sifts. It was introduced into a Hibitane solution at 0.5% for 3 minutes, followed by three washes with LB medium diluted 10 times in sterile distilled water.
Once disinfected, the eggs were removed from the sift and were carefully resuspended with a LB medium solution diluted 10 times in sterile distilled water. The final result of the distribution was checked by counting and registering the eggs in each well with an inverted Olympus microscope, observations of the uniformity of the evolutionary state in this phase were made too.
The Haemonchus spp and T. colubriformis' eggs hatch between 24 and 48 hours of incubation at 28° C., whereas the D. vivparus' eggs hatch before 24 hours. A good sample preparation is accomplished when in all the untreated controls more than 60% of hatching occurs in the previously foreseen times for each species.
The collection of egg mass of Meloidogyne incognita was performed from squash roots ( Cucurbita pepo ), previously infested and cultivated in greenhouses. For this operation a stereoscope microscope and needles with properly altered tips were used. The masses were put in sterile distilled water in Petri dishes at 28° C., in a number of 50 masses per dish. Daily observations were made to check egg hatching. In approximately 72 hours, there were enough larvae to start collecting and disinfecting.
The total volume of water containing the egg masses and the larvae were filtered through a sift net of 60 μm. From that moment on all the manipulation was done under aseptic conditions in a vertical laminar flow, using 24-well tissue culture plates. The eggs detached from the mass were unable to hatch and remained on the sift net of 30 μm; the larvae were collected with a further net of 5 μm. It was introduced into a Hibitane solution at 0.5% for 3 minutes followed by 3 washes with LB medium diluted 10 times in sterile distilled water. Once disinfected, the Meloidogyne incognita larvae were removed from the sift net and carefully resuspended with a LB medium solution diluted 10 times in sterile distilled water. The final collecting and disinfecting results were checked by counting and registering the live larvae with an inverted Olympus microscope.
The nematode's eggs and larvae were placed in a number of 100 individuals in approximately 2 ml of LB medium diluted 10 times. This volume was introduced into safety valves that allow the air to go through the liquid and, therefore, the gasses make contact with the eggs and larvae. Every valve was a replica for each treatment.
The hydrogen sulfide was obtained by a reaction against the chloride acid of two sulfide salts (Na 2 S and FeS), and from an anaerobial fermentation of bacterium Desulfovibrio desulfuricans subs. desulfuricans ATCC 27774 (isolated from an ovine rumen). The chitinolytic enzyme used was chitinase SIGMA C 1650, from bacterium Serratia marcescens.
The nematode's eggs and larvae under the study were subjected to the following treatments for 24 hours:
1. Control treatment: chitinase not applied, and air circulated through the valve.
2. Chitinase treatment: chitinase at a rate of 0.2 units per replica.
3. Sulfide treatment: hydrogen sulfide from Na 2 S with a 0.2 flux at 0.3 mg/minute.
4. Sulfide treatment: hydrogen sulfide from FeS with a 0.2 flux at 0.3 mg/minute.
5. Sulfide treatment: hydrogen sulfide from Desulfovibrio desulfuricans with a 0.2 flux at 0.3 mg/minute.
6. Combined treatment: simultaneous application of treatments 2 and 3.
7. Combined treatment: simultaneous application of treatments 2 and 4.
8. Combined treatment: simultaneous application of treatments 2 and 5.
All the above treatments had 4 replicas.
Twenty-four hours after starting the experiment the emerging larvae ( Haemonchus sp., T. colubriformis and D. viviparous ) and the number of live larvae ( Melodogyne incognita ) in all the treatments, were counted. The effectiveness results (E) are shown in table 1. This value is the mean of the 4 replicas in every treatment. The variance analysis (ANOVA) was applied to the results obtained in each nematode species in the study, separately; the Duncan test (Lerch G. 1977. La Experimentación en las ciencias biológicas y agrícolas. 1 ra edición, p.p. 203-308, Editorial Científico-Técnica, La Habana) was applied, which is also shown in table 1. Equal letters indicate that there are no significant differences (p<0.05) among the treatments.
TABLE 1
Treatment effectiveness (E)*
Treatment effectiveness (E)*
1. Ec
6. Eqsn
7. Eqsf
8. Eqsd
Control
2. Eq
3. Esn
4. Esf
5. Esd
(2 + 3)
(2 + 4)
(2 + 5)
Haemonchus
0.00
0.32
0.41
0.40
0.37
0.86
0.85
0.82
(a)
(b)
(c)
(c)
(b, c)
(d)
(d)
(d)
Trichostrongilus
0.00
0.37
0.40
0.39
0.38
0.88
0.88
0.83
(a 1 )
(b 1 )
(b 1 , c 1 )
(b 1 , c 1 )
(b 1 , c 1 )
(d 1 )
(d 1 )
(d 1 )
Dictyocaulus
0.00
0.35
0.44
0.42
0.40
0.91
0.90
0.86
(a 2 )
(b 2 )
(c 2 )
(c 2 )
(b 2 , c 2 )
(d 2 )
(d 2 )
(d 2 )
Meloidogyne
0.00
0.39
0.51
0.52
0.47
0.95
0.93
0.90
(a 3 )
(b 3 )
(c 3 )
(c 3 )
(c 3 )
(d 3 )
(d 3 )
(d 3 )
*Effectiveness (E) is the result from subtracting the value of active frequency (Fr) for hatching or the live larvae from 1, regarding the case. Fr is the ratio between the number of emerging or live larvae in each treatment (Ntto) and the number of emerging or live larvae in treatment 1 (Nc): E = 1 − Fr, where Fr = Ntto − Nc; therefore, E = 1 − Ntto/Nc
To determine the synergic effect in treatments 6, 7 and 8, it was assumed that the events occurring in them are not excluding.
For this type of analysis, the expected effectiveness (EE) must be equal to the sum of the individual effects (EI), given by the effectiveness rendered to the chitinase action (Eq) and the effectiveness rendered to the hydrogen sulfide action (Esn, Esf and Esd), minus the intersection effect (ei) (Sigarroa, A. 1985. Biometría y diseño experimental. 1ra. Parte. Minist. Educación Sup. Ed. Pueblo y EducaciFón. Cap. 3. pag 69-107).
EE= Eq+Es−ei , where ei=Eq×Es
If the experimental effectiveness (E) in the treatments where two nematicidal agents combine (treatments 6, 7, 8) is greater than the expected effectiveness (EE) for those treatments, it can be assured that there is synergism in terms of the nematicidal activity of the chitinolytic agent (chitinase) and the hydrogen sulfide when both are concurrently applied in the same treatment. The values obtained are summarized in table 2.
TABLE 2
Experimental (E) and expected (EE) effectiveness.
Experimental (E) and expected (EE) effectiveness.
Tratamiento 6
Tratamiento 7
Tratamiento 8
E
EE
E
EE
E
EE
Haemonchus
0.86
0.60
0.85
0.59
0.82
0.57
Trichostrongilus
0.88
0.62
0.88
0.62
0.83
0.61
Dictyocaulus
0.91
0.64
0.90
0.62
0.86
0.61
Meloidogyne
0.95
0.70
0.93
0.71
0.90
0.68
In the three treatments where chitinase and hydrogen sulfide are simultaneously combined, the experimental effectiveness (E) was greater than the expected effectiveness (EE) for the four nematodes under the study, which statistically demonstrates the existence of synergism between both compounds (when they act concurrently), regarding their nematicidal activity. No significant differences were observed as to the origin of the sulfides and their nematicidal effect (TABLE1).
Example 2
Greenhouse Evaluation of the Nematicidal Effect of a Chitinolytic-Activity Inducing Agent (Chitin) and a Hydrogen Sulfide-Producing Agent ( Desulfovibrio desulfuricans subps. desulfuricans ATCC 29577 Isolated from the Soil)
Brown soil with neutral pH was selected: it was dried and sieved with a 0.5 cm net to remove the undesirable particles. It was sterilized in a vertical autoclave for 1 hour at 120° C. and 1 atmosphere (Sambrook J., Fritsch E. F. and Maniatis T. 1989. Molecular Cloning: A Laboratory Manual. 2 nd . Ed. Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y., USA). It was dried at room temperature for 3-4 days to later make the foreseen mixtures in the treatments with river sand, soil worm humus and chitin (ICN catalogue number 101334).
Twenty pots (15 cm diameter×13 cm depth and 1 liter of capacity) were filled with the set proportions in the following treatments:
1. Control treatment: soil 70%, river sand 25% and humus 5%.
2. Chitin treatment: soil 70%, river sand 25%, humus 4% and chitin 1%.
3. Microorganic treatment: soil 70%, river sand 25%, humus 5% and D. desulfuricans , applied to a concentration of 10 10 CFU-pot.
4. Combined treatment: soil 70%, river sand 25%, humus 4%, chitin 1% and D. desulfuricans applied to a concentration of 10 10 CFU/pot.
Each treatment was carried out with 5 replicas (pots).
In treatments 2 and 4 a pre-mixture of humus with chitin was made in a 4:1 proportion, followed by a final mixture with the soil and the sand. In treatments 3 and 4 , D. desulfuricans was applied with 100 ml of de-ionized water per pot. These volumes were uniformly applied during the first irrigation.
For all the treatments, 500 nematode specimens of Radopholus similis previously collected from naturally infested banana roots were inoculated in the pots. The centrifugation-floatation technique (Jenkins, W. R. 1964. A rapid centrifugal-flotation technique for separation nematodes from soil. Plant Disease Reporter, 48: 692) was used; the specimens were diluted in 5 ml of distilled water and uniformly applied at a depth of 5 cm under the soil surface.
The pots were placed in greenhouses and remained still for three days after applying the treatments and inoculating the nematodes. Daily irrigation was performed during this stage, in order to preserve the good moisture conditions. Before the fourth day of treatments, a banana plant var. Cavendish , achieved by in vitro tissue culture, was transplanted to the pots. From that moment on a strict irrigation regime followed, which allowed permanent soil moisture in its field capacity.
The final evaluation was done three months after the experiment was initiated, the plant's roots were carefully removed from the soil. Then the number of specimens (larvae and adults) and live nematodes collected from the plants, were registered, using the centrifugation-floatation technique (Jenkins, W. R. 1964. A rapid centrifugal-flotation technique for separation nematodes from soil. Plant Disease Reporter, 48: 692), and an inverted microscope for the counts. The effectiveness results for the different treatments are shown in table 3. This is the mean value of the 5 replicas for each treatment. The variance analysis was applied to the results achieved (ANOVA), followed by the Duncan test (Lerch G. 1977. La Experimentación en las ciencias biológicas y agrícolas. 1 ra edición, p.p. 203-308, Editorial Científico-Técnica, La Habana), shown in table 3. Equal letters indicate that that there are no significant differences (p<0.05) among the treatments.
TABLE 3
Treatment effectiveness (E)*
Treatment effectiveness (E)*
1. Ec
2. Eq
3. Esd
4. Eqsd
Radopholus similis
0.00(a)
0.21(b)
0.18(b)
0.48(c)
*Effectiveness (E) is the result from subtracting the live specimen relative frequency (Fr) value from 1. Fr is the ratio between the number of live specimens in each treatment (Ntto) and the number of live specimens in treatment 1 (Nc): E = 1 − Fr, where Fr = Ntto/Nc, therefore, E = 1 − Ntto/Nc.
To determine the possible synergic effect in treatment 4, it was assumed that the occurring events (nematicidal effect), are not excluding.
Like Example 1, the expected effectiveness (EE) must be equal to the sum of the individual effects (EI), given by the effectiveness rendered to chitin action (Eq) as an inductor of the chitinolytic activity of the microorganisms present in the mixture of soil and humus, and the effectiveness rendered to the action of hydrogen sulfide (Esd) from bacteria D. desulfuricans ; minus the intersection effect (ei) between the two treatments (Sigarroa, A. 1985. Biometría y diseño experimental. 1ra. Parte. Minist. Educación Sup. Ed. Pueblo y Educación. Cap. 3. pag 69-107)
EE= Eq+Es−ei , where ei=Eq×Es
If the experimental effectiveness (E) in treatment 4 where the two nematicidal agents are combined, is greater than the expected effectiveness (EE), it can be assured that there is synergism between the chitinolytic activity-inducing agent (chitin) and hydrogen sulfide (from D. desulfuricans ), where they are concurrently applied in the same treatment. The values obtained are shown in table 4.
TABLE 4
Experimental (E) and expected (EE) effectiveness.
Experimental (E) and expected (EE)
effectiveness
Treatment 4.
E
EE
Radopholus similis
0.48
0.35
In treatment 4 a chitinolytic activity inductor (chitin), and a biological source of hydrogen sulfide ( D. sulfuricans ) are combined. In this case the experimental effectiveness (E) was greater than the expected effectiveness (EE), thus proving the existence of synergism (regarding its nematicidal activity) in the two compounds when they are concurrently applied in the soil.
Example 3
Demonstration of Chitinolytic Activity and Sulfide Production from Bacteria Corynebacterium paurometabolum C-924 and Tsukamurella paurometabola DSM 20162
Sulfide Production Determination:
In tubes of 100 ml for gas collection, samples from the gas current from fermentation of strains C-924 and DSM 20162 in 51 bioreactors, were taken. The total culture time was 24 h. The formation of hydrogen sulfide was detected first at the 16 th h.
The samples were processed in an analogous manner to the H 2 S pattern generated. The analysis was performed in the Varian gas chromatograph, following these conditions:
Flame photometric detector with filter sensitive to compounds that contain sulfur. Hydrogen sulfide pattern: 43.2 ng/ml, by duplicate. Samples: duplicate for each time when sampling was done. Injection: 1 ml or μl of head space. Column: DB-5 (15 m×0.53 mm) Temperature: 35° C. Carrier gas: Nitrogen 1.5 ml/min. Detector: FPD-S Purge gas: Nitrogen 30 ml/min.
Table 5 shows a summary of the sulfide gases analysis issued by the two strains at different times.
TABLE 5
Sulfide gases analysis
H 2 S flux mg/min (Sulfide flux detected)
16
18
20
22
24
Strains
Samples
hours
hours
hours
hours
hours
C-924
1
0.0673
0.2208
0.4779
0.3578
0.0672
2
0.0659
0.2160
0.4755
0.3552
0.0680
DSM
1
0.0231
0.0416
0.1014
0.1863
0.0009
20162
2
0.0240
0.0422
0.1040
0.1887
0.0097
Both strains produce sulfides, but C-924 produces higher flux than strain DSM 20162.
Chitinolytic Activity Determination:
Corynebacterium paurometabolum C-924, Tsukamurella paurometabola DSM 20162, Serratia marcescen ATCC 13880 and E. coli ATCC 25922 strains, were used.
The bacterial cultures of the studied strains were grown in LB medium at 28° C. and 100 rpm for 24 hours, followed by centrifugation at 3500 rpm; the supernatants were filtered through two 0.2 μm nets. The filtered product was assayed in plates prepared with a chitin colloidal suspension (0.5%), agarose was added too, up to 0.8%, to achieve the medium gelling and assure porosity to facilitate protein diffusion. After gelling, 5 mm diameter wells were opened, where 100 μl of the filtered supernatant from each bacterial strain was added. Three replicas were used for every plate, and were incubated at 28° C. in the dark.
From the 48 th hour on, a decrease was observed in the medium turbidity resembling a halo, which demonstrated chitin hydrolysis. In the following table (TABLE 6), the qualitative results from the occurrence of a hydrolysis halo at different incubation times with the supernatant from the culture of the different strains studied, are shown.
TABLE 6
Occurrence of a hydrolysis halo.
Strains
24 hours
48 hours
72 hours
S. marcescen .
Negative
Positive +
Positive +++
C. paurometabolum
Negative
Negative
Positive ++
T. paurometabola .
Negative
Negative
Positive +
E. coli .
Negative
Negative
Negative
+++ refers to the greatest hydrolysis halo observed,
++ refers to an intermediate hydrolysis halo, and
+ refers to the least hydrolysis halo observed.
Both strains ( C. paurometabolum and T. paurometabola ) showed the chitin-hydrolysis halo, just like the positive control used ( S. marcescen ), whereas the E. coli strain (negative control) did not produce a hydrolysis halo.
Example 4
In Vitro Evaluation of Effects from Sulfides and Chitinases, Produced by Bacteria Corynebacterium paurometabolum C-924 and Tsukamurella paurometabola DSM 20162, on Parasite Fasciola hepatica (Trematode)
Eggs from parasite Fasciola hepatica were used. The egg collections were directly made from the infested liver bile of a bovine (cattle), previously sacrificed. The bile content was resuspended in a 3 times higher volume of distilled water and remained still for 2-3 hours at 28° C., to achieve egg precipitation. Then the greatest possible volume of supernatant liquid was removed. The precipitate was filtered through a sift net of 71 μm, where the eggs were trapped.
From that moment on, all the manipulation was done under aseptic conditions in a vertical laminar flow, using 24-well tissue culture plates. The sift with the F. hepatica eggs was introduced into a Hibitane solution at 0.5% for 3 minutes, followed by 3 washes with LB medium diluted 10 times in sterile distilled water. Once disinfected, the eggs were removed from the sift and were carefully resuspended with a LB medium solution diluted 10 times in sterile distilled water. The final collecting and disinfecting results were checked by counting and registering the live larvae with an inverted Olympus microscope.
Observations regarding the uniformity of the evolutionary state in this phase, were made as well.
This parasitic trematode's eggs hatch under the previously in vitro set conditions in about 15 days of incubation at 28° C.; a good preparation of the sample was considered when more than 60% of the eggs hatched at the end of the incubation period.
To develop the experiment, the disinfected eggs were placed in a number of 100 individuals approximately, in 1 ml of LB medium diluted 10 times. The volume was uniformly introduced in 20 safety valves that allow the air passage through the liquid; hence, the gases make contact with the eggs. Each valve was a replica (4 per treatment) in all the five treatments.
The F. hepatica eggs were exposed to the following treatments during the last 4 days of incubation:
1. Control treatment: Addition of 1 ml of LB medium diluted 10 times to every valve, with no chitinase, and air circulating through it.
2. Addition to each valve of 1 ml of a chitinolytic supernatant without bacterial cells from a culture of 10 10 Colony Forming Units per milliliter (CFU/ml) of Corynebacterium paurometabolum C-924.
3. Addition to each valve of 1 ml of a chitinolytic supernatant without bacterial cells, from a 10 10 CFU/ml of Tsukamurella paurometabola DSM 20162.
4. The flux of gases from a continuous culture of Corynebacterium paurometabolum C-924 at 10 10 CFU/ml, was allowed to go through the valves.
5. The flux of gases from a continuous culture of Tsukamurella paurometabola DSM 20162 at 10 10 CFU/ml, was allowed to go through the valves.
6. Combined treatment: simultaneous application of treatments 2 and 4.
7. Simultaneous treatment: simultaneous application of treatments 3 and 5.
On the fourth day following the start of the experiment, the hatched eggs were counted. In the case of F. hepatica , it was not possible to count the larvae (miracides) that come out due to the great motility they have; therefore, observations through the microscope are focused on the eggs. The effectiveness results from the different treatments are shown in table 7. This is the mean value for the 4 replicas in each treatment. Equal letters indicate the lack of significant differences (p<0.05) among the treatments.
TABLE 7
Treatment effectiveness (E)*
Treatment effectiveness (E) *
1. E
2. Eq
3. Eq
4. Es
5. Es
6. E
7. E
Control
C-924
DSM20162
C-924
DSM20162
(2 + 4)
(3 + 5)
Fasciola hepatica
0.00
0.18
0.11
0.29
0.16
0.52
0.28
(a)
(b)
(c)
(d)
(b, c)
(e)
(d)
The effectiveness * is the result from subtracting the relative frequency (Fr) of hatching value from 1. Fr is the ratio between the number of hatched eggs in every treatment (Ntto) and the number of eggs hatched in treatment 1 (Nc): E = 1 − Fr, where Fr = Ntto/Nc; therefore, E = 1 − Ntto/Nc
To determine the possible synergic effect in treatments 6 and 7, it was assumed that the events (anti-parasitic effect) occurring in them, are not excluding.
For this type of analysis, the expected effectiveness (EE) is given by the effectiveness rendered to the chitinase action (Eq) and the effectiveness rendered to the action of hydrogen sulfide (Esn, Esf and Esd), minus the intersection effect (ei) (Sigarroa, A. 1985. Biometría y diseño experimental. 1ra. Parte. Minist. Educación Sup. Ed. Pueblo y Educación. Cap. 3. pag 69-107).
EE= Eq+Es−ei , where ei=Eq×Es
If the experimental effectiveness (E) in the treatments where two anti-parasitic agents combine (treatments 6 and 7), is greater than the expected effectiveness for these treatments, it can be assured that there is synergism in terms of the anti-parasitic activity of the chitinolytic agent (chitinase) and hydrogen sulfide when both are concurrently applied in the same treatment. The values obtained are summarized in table 8.
TABLE 8
Experimental (E) and Expected (EE) effectiveness.
Experimental (E) and Expected (EE) effectiveness.
Treatment 6
Treatment 7
E
EE
E
EE
Fasciola hepatica
0.52
0.31
0.28
0.25
In the treatments where chitinase and hydrogen sulfide are combined, the experimental effectiveness (E) was greater than the expected effectiveness (EE), which demonstrates the synergism of the two compounds when acting concurrently in terms of their nematicidal activity.
Example 5
In Vitro Effect Evaluation of a Bacterial Strain ( Corynebacterium paurometabolum C-924) which Produces Hydrogen Sulfide and has Chitinolytic Activity on Several Bacteria and Fungi
The following fungus species were used: Pestalotia palmarum, Alternaria tabacina, Sarocladium orizae, Pitium debaryanum ; and the following bacterial species: Erwinia chrysanthemi, Burkholderia glumae, Serratia marcescen ATCC 13880, Bacillus subtilis F 1695 and Escherichia coli ATCC 25922, were used as well.
A) Fungus Assay.
The interaction of Corynebacterium paurometabolum C-924 on fungi was assayed on these fungi: Pestalotia palmarum, Alternaria tabacina, Sarocladium orizae and Pytium debayianum . Strain of Serratia marcescen ATCC 13880 was used as the positive control for fungicidal activity and E. coli strain ATCC 25922 was used as the negative control for fungicidal activity. The bacterial cultures were grown with the usual shaking and temperature conditions for all species in 24 hours. The necessary dilutions were made with absorbance at λ530 nm to assure a cell concentration of 10 9 cfu/ml. They were placed in petry dishes containing PDA medium (agar-potato-dextrose), the inocula were made with a central line and the aid of the microbiological loop. The dishes were incubated for 48 hours at 28° C., then the 8 mm diameter discs from the different fungal strains previously grown were inoculated (plates containing PDA medium) and placed on the plate's surface at either pole regarding the central line of the inoculated bacteria. Three replicas were used for each fungus to be studied and were incubated for 10 days at 28° C. The results were read from the fifth day of the beginning of the experiment on.
b) Bacterium Assay.
The incidence of the interaction of Corynebacterium paurometabolum C-924, E. coli ATCC 25922 and Bacillus subtilis F 1695 was studied in these bacteria: Erwinia chrysanthanem and Burkholderia glumae . The Bacillus subtilis strain F 1695 was used as the positive control for antagonism with other bacteria, for the negative control E. coli strain ATCC 25922 was used. The bacterial strains were grown in LB medium under the usual shaking and temperature conditions for 24 hours. From these cultures, the necessary dilutions were made, with a previous absorbance reading at λ530 nm to assure a cell concentration of 10 9 cfu/ml. In the case of C-924, drops of 5 μl were applied on three different sites on plates with LB medium, on two different sites for the positive control and two other different sites for the negative control, respectively. The plates were incubated at 28° C. for 48 hours. After that time they were treated with chloroform steam for 3 minutes (to inactivate and avoid dispersion in further steps), then the plates were left in the laminar flow, half-open, to eliminate the gas excess. Inoculation of the challenging strains Erwinia chrysanthemi and Burkholderia glumae , was carried out, which started with pure cultures from every microorganism from which the necessary amounts to make a cellular concentration of 10 9 cfu/ml were taken, after adding up to three milliliters of semi-solid LB medium (0.1% technical agar No. 3) The mixture was dispersed on the plates containing the challenged strains, then they were incubated at 28° C. for 48 hours to evaluate the results.
Table 9 shows the description of the results accomplished during the above mentioned interaction assays.
TABLE 9
Results accomplished during interaction assays.
Antagonistic effect of
Species
Description
strain C-924.
Pestalotia palmarum
Fungus, Deuteromiceto, phytopathogenic of
+++
foliage and fruits.
Alternaria tabacina
Fungus, Deuteromiceto, phytopathogenic of
+++
tobacco leaves.
Sarocladium orizae
Fungus, Deuteromiceto, phytopathogenic of
++
rice, it is involved in the acarus-fungus
complex, affecting seeds, sheath and neck.
Pytium debaryanum
Fungus, Oomiceto, lives on the soil and is
+
part of the causative Damping-off complex.
Erwinia
Bacterium, isolation of Dahlia stems with
+++
chrysanthemi
soft rottenness symptoms.
Burkholderia glumae
Bacterium, isolation of rice plants with apical
++
and marginal necrosis.
Bacillus subtilis
Bacterium, isolation of potato rhyzosphere
−
cepa F1695
in rottenness-free on affected field.
Biorregulator.
+++: Strong antagonism is observed when growth stops and causes the formation of a halo by the effect of C-924. In the case of fungi the typical radial growth is inhibited.
++: Mean antagonist effect of C-924 on the microorganism.
+: Slight antagonist effect of C-924 on the microorganism.
−: No antagonist effect of C-924 is observed on the microorganism.
As shown in table 9, there is a marked antagonist effect of strain Corynebacterium paurometabolum C-924 on fungi Pestlotioa palmarum, Alternaria tabacina and Sarocladium orizae , which are characterized by having a high chitin content in their structures. Only a slight antagonism caused by the action of hydrogen sulfide was observed. In the case of the interaction with the bacteria studied, the antagonism was observed in the two pathogenic strains ( Erwinia crhysanthemi and Burkholderia glumae ), whereas antagonism was not observed in the case of Bacillus subtilis , as it is isolated from an antagonist soil with other microorganisms and; therefore, more resistant to adverse environmental factors. | This invention relates to pesticide and antiparasitic compositions for the control of pests, diseases and parasites attacking plants and animals. The compositions include, at least one chitinolytic agent or a chitinolytic activity-inducing agent, and sulfide or a sulfide-producing agent from microorganisms or chemical compounds, wherein the chitinolytic agent or the chitinolytic activity-inducing agent and sulfur or a sulfur-producing agent obtaining from microorganisms or chemical compounds are concurrently applied at a range significantly lower than any of the above-mentioned compounds, when they are individually to attain effective control. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an amplifier circuit that samples input signals and outputs signals obtained by applying a gain to the sampled input signals having different voltages.
[0003] 2. Description of the Related Art
[0004] In video equipment using a solid-state image pickup device such as a CCD (Charge Coupled Device), a correlation double sampling circuit (CDS) and a variable gain amplifier circuit (PGA) are used so that the noise of a video signal from the solid-state image pickup device is eliminated and the signal itself is amplified with a prescribed gain. In the CDS and PGA, an amplifier circuit composed of a switched capacitor circuit is conventionally used. For example, Patent Document 1 describes a differential amplifier circuit composed of a switched capacitor circuit.
[0005] FIG. 1 shows the conventional differential amplifier circuit composed of the switched capacitor circuit. The differential amplifier circuit 10 shown in FIG. 1 is composed of a full differential amplifier circuit 11 , switches SW 1 , SW 2 , SW 3 , SW 4 , SW 5 , SW 6 , SW 7 , and SW 8 , and capacitors Cs and Cf. The differential amplifier circuit 11 is connected to, for example, an external device 12 that outputs signals to be amplified. The external device 12 represents, for example, a solid-state image pickup device that outputs video signals to be amplified. The operations of the differential amplifier circuit 11 are described below.
[0006] At a sampling operation in the differential amplifier circuit 11 , the switches SW 1 , SW 2 , SW 4 , SW 5 , and SW 8 are turned on, and the switch SW 3 is turned off. A reference voltage Vref 2 is supplied to the switches SW 6 and SW 7 . At this time, signals output from the external device 12 are input to input terminals Vip and Vim, and an electrical charge corresponding to a potential difference between a standard voltage Vref 1 and the input signals is stored in the capacitors Cs. Furthermore, both outputs from the full differential amplifier circuit 11 are short-circuited by the switch SW 8 , and an electrical charge corresponding to a potential difference between the standard voltage Vref 1 and the reference voltage Vref 2 is stored in the capacitors Cf via the switches SW 6 and SW 7 .
[0007] Then, when the sampling operation is completed to establish a signal output state, the switches SW 1 , SW 2 , SW 4 , SW 5 , and SW 8 are turned off, and the switch SW 3 is turned on. The switches SW 6 and SW 7 are connected to the outputs of the full differential amplifier circuit 11 . At this time, the one terminal of the capacitors Cs is short-circuited to have the same potential as the other terminal thereof, which in turn moves the electrical charges stored in the capacitors Cs to the capacitors Cf. Accordingly, a potential difference Vop−Vom in the outputs of the full differential amplifier circuit 11 is calculated according to the following formula.
[0000] Vo=Vop−Vom=Cs/Cf×{ ( Vip−V ref1)−( Vim−V ref1)}= Cs/Cf× ( Vip−Vim ) (1)
[0008] From the above formula (1), it is found that the gain of the full differential amplifier circuit 11 in the amplifier circuit 10 is determined by the ratio of the capacitors Cs to the capacitors Cf.
[0009] Patent Document 1: JP-A-2006-174091
[0010] However, the above formula (1) according to the conventional art does not take the offset voltage Voff of the full differential amplifier circuit 11 into consideration, but it includes an error as shown in the following formula (2).
[0000] Vo=Vop−Vom=Cs/Cf× ( Vip−Vim+Voff ) (2)
SUMMARY OF THE INVENTION
[0011] The present invention has been made in light of the above circumstances and may provide an amplifier circuit capable of having improved characteristics without being influenced by an offset voltage.
[0012] According to an aspect of the present invention, there is provided an amplifier circuit including a first input terminal; a second input terminal; a first differential amplifier circuit that samples signals input to the first and second input terminals and outputs signals obtained by applying a gain to the sampled input signals having different voltages; and a second differential amplifier circuit that supplies first and second reference voltages referred to when a sampling operation is performed in the first differential amplifier circuit to the first and second input terminals, respectively. A potential difference between the first and second reference voltages is equal to an offset voltage of the first differential amplifier circuit.
[0013] Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 shows a conventional differential amplifier circuit composed of a switched capacitor circuit;
[0015] FIG. 2 shows the amplifier circuit 100 of a first embodiment;
[0016] FIG. 3 shows the amplifier circuit 100 A of a second embodiment; and
[0017] FIG. 4 shows the amplifier circuit 100 B of the third embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] According to embodiments of the present invention, at a sampling operation in a differential amplifier circuit, a potential difference between a first reference voltage supplied to a first input terminal and a second reference voltage supplied to a second input terminal is set to be equal to the offset voltage of the differential amplifier circuit, thereby making it possible to cancel the offset voltage. As a result, the characteristics of an amplifier circuit can be improved.
First Embodiment
[0019] Referring to the accompanying drawing, a description is now made of a first embodiment of the present invention. FIG. 2 shows an amplifier circuit 100 of the first embodiment.
[0020] The amplifier circuit 100 of the first embodiment is configured of a first differential amplifier circuit 110 , a second differential amplifier circuit 120 , switches SW 10 SW 20 , SW 30 , SW 40 , SW 50 , SW 60 , SW 70 , and SW 80 , and capacitors Cs 1 , Cs 2 , Cf 1 , and Cf 2 . Note that the capacitors Cs 1 and Cs 2 are capacitors having the same capacitance, and the capacitance of the capacitors Cs 1 and Cs 2 is represented as Cs. Furthermore, the capacitors Cf 1 and Cf 2 are capacitors having the same capacitances, and the capacitance of the capacitors Cf 1 and Cf 2 is represented as Cf.
[0021] In this embodiment, an inverting input terminal T 1 of the differential amplifier circuit 110 is connected to one end of the capacitor Cs 1 , one end of the switch SW 40 , and one end of the capacitor Cf 1 . Furthermore, a non-inverting input terminal T 2 of the differential amplifier circuit 110 is connected to one end of the capacitor Cs 2 , one end of the switch SW 50 , and one end of the capacitor Cf 2 . The other end of the capacitor Cs 1 is connected to one end of the switch SW 10 and one end of the switch SW 30 . The other end of the capacitor Cs 2 is connected to one end of the switch SW 20 and the other end of the switch SW 30 .
[0022] The other ends of the switches SW 10 and SW 20 are connected to the input terminals Vip and Vim of the amplifier circuit 100 of this embodiment, respectively. The input terminals Vip and Vim are connected to an external device 130 . Note that the external device 130 of this embodiment represents, for example, a device that outputs a signal to be amplified by the amplifier circuit 100 , such as a solid-state image pickup device that outputs a video signal or the like to be amplified.
[0023] The other end of the capacitor Cf 1 is connected to either a standard voltage source 140 that generates a standard voltage Vref or a first output terminal T 3 of the differential amplifier circuit 110 via the switch SW 60 . The other end of the capacitor Cf 2 is connected to either a standard voltage source 150 that generates the standard voltage Vref or a second output terminal T 4 of the differential amplifier circuit 110 via the switch SW 70 . Furthermore, the switch SW 80 is connected between the output terminals T 3 and T 4 of the differential amplifier circuit 110 .
[0024] The other end of the switch SW 40 is connected to an inverting input terminal T 5 of the differential amplifier circuit 120 . The inverting input terminal T 5 of the differential amplifier circuit 120 is connected to a first output terminal T 7 of the differential amplifier circuit 120 . The other end of the switch SW 50 is connected to a non-inverting input terminal T 6 of the differential amplifier circuit 120 . The non-inverting input terminal T 6 of the differential amplifier circuit 120 is connected to a second output terminal T 8 of the differential amplifier circuit 120 . Accordingly, the input and output terminals of the differential amplifier circuit 120 are short-circuited. In this embodiment, the voltage of the inverting input terminal T 5 of the differential amplifier circuit 120 is defined as a first reference voltage (voltage Vc 1 ), and the voltage of the non-inverting input terminal T 6 thereof is defined as a second reference voltage (voltage Vc 2 ).
[0025] In this embodiment, the configuration of the differential amplifier circuit 120 is the same as that of the differential amplifier circuit 110 . In other words, the offset voltage of the differential amplifier circuit 120 is set to be equal to that of the differential amplifier circuit 110 .
[0026] With this configuration, the following problem can be solved in this embodiment. For example, when a potential difference between the signals input to the input terminals Vip and Vim is about 1 V in the amplifier circuit 100 of this embodiment, an offset voltage Voff depends on the manufacturing tolerance of transistors inside the differential amplifier circuit 110 . Here, several millivolts (mV) of offset voltages are generated. The gain accuracy demanded under an environment in which the amplifier circuit 100 of this embodiment is used is about 1/1000. Therefore, an error caused by the offset voltage exceeds a tolerance, which results in degradation in the characteristics of the amplifier circuit 100 .
[0027] In order to deal with the above problem, the offset voltage of the differential amplifier circuit 110 is cancelled to eliminate influences due to the offset voltage in this embodiment.
[0028] The operations of the amplifier circuit 100 are described below.
[0029] First, a sampling operation in the amplifier circuit 100 of this embodiment is described. At the sampling operation in the amplifier circuit 100 of this embodiment, the switches SW 10 , SW 20 , SW 40 , SW 50 , and SW 80 are turned on, and the switch SW 30 is turned off. Furthermore, the switches SW 60 and SW 70 are connected to the standard voltage sources 140 and 150 that generate the standard voltage Vref, respectively.
[0030] At this time, signals from the external device 130 are input to the input terminals Vip and Vim of the amplifier circuit 100 , and a reference voltage Vc 1 is supplied to the capacitor Cs 1 via the switch SW 40 . Furthermore, a reference voltage Vc 2 is supplied to the capacitor Cs 2 via the switch SW 50 . Accordingly, an electrical charge corresponding to a potential difference between the reference voltage Vc 1 and the signal supplied to the input terminal Vip is stored in the capacitor Cs 1 . Furthermore, an electrical charge corresponding to a potential difference between the reference voltage Vc 2 and the signal supplied to the input terminal Vim is stored in the capacitor Cs 2 .
[0031] Furthermore, an electrical charge corresponding to a potential difference between the standard voltage Vref and the reference voltage Vc 1 is stored in the capacitor Cf 1 via the switch SW 60 . Furthermore, an electrical charge corresponding to a potential difference between the standard voltage Vref and the reference voltage Vc 2 is stored in the capacitor Cf 2 via the switch SW 70 .
[0032] Here, the input and output terminals of the differential amplifier circuit 120 are short-circuited. Therefore, the reference voltage Vc 1 output from the output terminal T 7 of the differential amplifier circuit 120 and the reference voltage Vc 2 output from the output terminal T 8 thereof are output with the potential difference corresponding to the offset voltage of the differential amplifier circuit 120 .
[0033] Next, an operation in the amplifier circuit 100 of this embodiment after the completion of the sampling operation is described.
[0034] When the sampling operation is completed to establish a signal output state in the amplifier circuit of this embodiment, the switches SW 10 , SW 20 , SW 40 , SW 50 , and SW 80 are turned off, and the switch SW 30 is turned on. Furthermore, the switch SW 60 is connected to the output terminal T 3 of the differential amplifier circuit 110 , and the switch SW 70 is connected to the output terminal T 4 thereof.
[0035] At this time, the capacitors Cs 1 and Cs 2 are short-circuited by the switch SW 30 to have the same potential. Therefore, the electrical charges are moved to the capacitors Cf 1 and Cf 2 . Accordingly, a potential difference (Vop−Vom) between the voltages of the output terminals T 3 and T 4 of the differential amplifier circuit 110 is calculated according to the following formula (3).
[0000] Vo=Vop−Vom=Cs/Cf×{ ( Vip−Vc 1)−( Vim−Vc 2)+ Voff} (3)
[0036] The offset voltage Voff is included in the above formula (3). Therefore, an error is caused in the output voltage Vo. In this embodiment, however, a potential difference between the reference voltages Vc 1 and Vc 2 is equal to the offset voltage Voff of the differential amplifier circuit 110 . Therefore, the output voltage Vo is finally calculated according to the following formula (4).
[0000] Vo=Vop−Vom=Cs/Cf×{ ( Vip−Vc 1)−( Vim−Vc 1 +Voff )+ Voff}=Cs/Cf× ( Vip−Vim ) (4)
[0037] According to the above formula (4), it is found that the offset voltage Voff is cancelled.
[0038] As described above, the amplifier circuit 100 of this embodiment is provided with the differential amplifier circuit 120 that supplies the reference voltages Vc 1 and Vc 2 having the same potential difference as the offset voltage Voff of the difference amplifier circuit 110 . Therefore, the offset voltage Voff of the differential amplifier circuit 110 can be cancelled. As a result, according to this embodiment of the present invention, the characteristics of the amplifier circuit 100 can be improved without being influenced by the offset voltage.
Second Embodiment
[0039] Referring to the accompanying drawing, a description is now made of a second embodiment of the present invention. The second embodiment of the present invention is different from the first embodiment only in that it is provided with switches SW 90 and SW 100 instead of the switch SW 30 of the first embodiment. Therefore, a description is made only of the difference between the first and second embodiments. In addition, components the same as those of the first embodiment are denoted by the same reference numerals and their descriptions are omitted in this embodiment.
[0040] FIG. 3 shows an amplifier circuit 100 A of the second embodiment. In the amplifier circuit 100 A of this embodiment, the switch SW 30 of the first embodiment that short-circuits the capacitors Cs 1 and Cs 2 is replaced by the switches SW 90 and SW 100 .
[0041] One end of the switch SW 90 is connected to one end of the capacitor Cs 1 , and the other end thereof is connected to the input terminal T 5 of the differential amplifier circuit 120 . Furthermore, one end of the switch SW 100 is connected to one end of the capacitor Cs 2 , and the other end thereof is connected to the input terminal T 6 of the differential amplifier circuit 120 .
[0042] The switches SW 90 and SW 100 are turned on and off at the same timing as the switch SW 30 of the first embodiment. In other words, the switches SW 90 and SW 100 are turned off at the sampling operation and turned on when the sampling operation is completed to establish a signal output state.
[0043] With this configuration, the input terminals T 5 and T 6 of the differential amplifier circuit 120 are connected to the capacitors Cs 1 and Cs 2 , respectively, in the signal output state in this embodiment. Accordingly, in this embodiment, the voltages of the input terminals T 1 and T 2 are fixed in the signal output state. Therefore, it is possible to further ensure the time (settling time) required until sampling of the input signals of input voltages using a difference in on-resistance between the switches of the amplifier circuit 100 A is enabled. As a result, the distortions of an output voltage can be reduced.
Third Embodiment
[0044] Referring to the accompanying drawing, a description is now made of a third embodiment of the present invention. The third embodiment of the present invention is a modification of the amplifier circuit 100 A of the second embodiment. Therefore, a description is made only of the difference between the second and third embodiments. In addition, components the same as those of the second embodiment are denoted by the same reference numerals and their descriptions are omitted in this embodiment.
[0045] FIG. 4 shows an amplifier circuit 100 B of the third embodiment. The amplifier circuit 100 B of this embodiment is different from the amplifier circuit 100 A of the second embodiment in that it has capacitors C 1 and C 2 for ensuring an output provided in the output terminals T 7 and T 8 of the differential amplifier circuit 120 .
[0046] In this embodiment, the output voltages of the output terminals T 7 and T 8 are ensured by the capacitors C 1 and C 2 . Therefore, a switching noise called a kickback can be reduced. As a result, the characteristics of the amplifier circuit 100 B can be further improved.
[0047] Note that it is described in the first through third embodiments that the configuration of the differential amplifier circuit 120 has the same configuration as that of the differential amplifier circuit 110 . However, the configuration of the differential amplifier circuit 120 is not limited to this.
[0048] For example, the size of internal devices such as transistors constituting the differential amplifier circuit 120 may be different from that of internal devices constituting the differential amplifier circuit 110 .
[0049] If the size of the internal devices constituting the differential amplifier circuit 120 is made smaller than that of the internal devices constituting the differential amplifier circuit 110 , the amplifier circuit of the embodiments of the present invention can be downsized and the consumption power thereof can be reduced.
[0050] Furthermore, if the size of the internal devices constituting the differential amplifier circuit 120 is made larger than that of the internal devices constituting the differential amplifier circuit 110 , an output voltage can be further ensured, which is effective for a large kickback.
[0051] According to the embodiments of the present invention, the characteristics of the amplifier circuit can be improved without being influenced by an offset voltage.
[0052] The present invention is not limited to the specifically disclosed embodiments, and variations and modifications may be made without departing from the scope of the present invention.
[0053] The present application is based on Japanese Priority Application No. 2008-068460 filed on Mar. 17, 2008, the entire contents of which are hereby incorporated herein by reference. | An amplifier circuit is disclosed that includes a first input terminal; a second input terminal; a first differential amplifier circuit that samples signals input to the first and second input terminals and outputs signals obtained by applying a gain to the sampled input signals having different voltages; and a second differential amplifier circuit that supplies first and second reference voltages referred to when a sampling operation is performed in the first differential amplifier circuit to the first and second input terminals, respectively. A potential difference between the first and second reference voltages is equal to an offset voltage of the first differential amplifier circuit. | 7 |
BACKGROUND OF THE INVENTION
Plate-type heat exchangers are being more widely used for certain industrial applications in place of fin and tube or shell and tube type heat exchangers because they are less expensive and easier to make than most forms of heat exchangers. In one form of such plate exchangers, a plurality of plates are clamped together in a stacked assembly with gaskets located between adjacent plates and traversing a course adjacent to the plate peripheries. Flow of the two fluids involved in heat exchange is through the alternate ones of the layers defined by the clamped plates.
The stacked plates also can be joined together as a unitary structure by brazing the various components together. U.S. Pat. No. 4,006,776 discloses a plate heat exchanger made in such manner. U.S. Pat. No. 4,569,391 discloses a plate heat exchanger in which plural parallel spaced plates are welded together. The space between plates is occupied by nipple-like protuberances formed in the plates and which serve to increase turbulence in the fluid flow. All of the fluid flowing in a given defined space is in contact with the plates to thereby enhance heat transfer.
U.S. Pat. No. 4,561,494 also discloses employment of a turbulator, i.e., a turbulence producing device, in a plate heat exchanger. U.S. Pat. No. 4,398,596 discloses another construction of a plate heat exchanger in which spaced rectangular-shaped plates define a succession of fluid flow passages, the alternate ones of which are associated with the flow of the two fluids involved in heat exchange. The plates have four orifices located at the four plate corners. Two of these orifices are associated with one fluid flow and the other two with the second fluid flow. The orifices are aligned with tubular passages leading to the various fluid flow passages.
While plate heat exchangers of known construction and as exemplified in the aforementioned U.S. Patents, have the advantage of being less complicated and more easily fabricated than fin and tube types, they employ components that involve unnecessary assembly steps or possess shapes that entail undesirable shaping procedures. Further, they require maintaining a components inventory that could be reduced if a more simplified plate heat exchanger construction optimizing standardized components usage was provided. With a standardized system, it would be possible to provide a stacked plate exchanger that could be produced economically and efficiently on demand with a variety of different interchangeable structures to satisfy a wide variety of needs.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a plate type heat exchanger which is easily, economically and efficiently fabricated. For such purpose, plate components of simple structural character are employed thereby reducing the need for special components shaping devices and stocking of a multiplicity of different shaped elements.
Another object is to provide a plate heat exchanger having heat transfer cells which can be embodied in a compact heat exchanger structure in a given fluid cooling capacity for a wide range of industrial and/or commercial applications.
A further object is to provide a plate heat exchanger which is particularly suited for ready incorporation therein of any one or combinations of differently configured flow turbulator members for most efficiently matching the turbulator used to the characteristics and flow properties of the various fluids for which a heat exchanger is used.
In accordance with the invention, the plate heat exchanger is a brazed together unitary, elongated generally rectangular-shaped structure comprising a stacked assembly of substantially flat coextensive and superposed plates. The stacked assembly will, depending on particular heat transfer requirements, include at least one but most usually a plurality of heat transfer cells. It will be understood that a "cell" is constituted by two adjacently placed or alternating flow cavities in the assembly and wherein respective heated and cooling fluids flow.
The plate heat exchanger comprises a plurality of flow plates and a plurality of heat transfer plates arranged in an alternating stacked relationship with one another so that flow cavities are formed between the adjacent surfaces of the heat transfer and flow plates. A turbulator member is positioned in each flow cavity and it can be one of a plurality of differently configured turbulator shapes that can be employed interchangeably in any one of the heat exchanger cavities. The flexibility of being able to utilize any one or several of the differently configured turbulator members in the heat exchanger is a major advantage of the invention. It allows utilization of a standardized heat exchanger construction and fabrication procedure with simple modification thereto effected by utilizing any one or combination of freely selectable turbulator shapes to produce a heat exchanger specially adapted for a given cooling requirement and type of fluid.
The heat exchanger has an inlet and outlet for a first fluid and there is a passage network therebetween with the passage network being comprised of various network defining structure, e.g., openings, being present in the flow and heat transfer plates. A similar inlet and outlet and passage network arrangement is provided for a second fluid. Each turbulator member is located in the passage network of one of the fluids with the network so arranged that there is heat transfer between the fluids passing therethrough. The stacked plates and turbulators are sealingly interconnected to form them together in unitary structure form and the assembly can be provided with top and bottom plates. Where the assembly is interconnected by brazing, a thin braze alloy sheet can during assembly, be intervened between the alternating plates and following subjection of the assembly to a heated brazing environment, the braze alloy sheets will form alloy layers adhering to adjoining faces of the plates and also fluid-tightly seal the peripheral regions of the plate interfacings.
The plates from which the heat exchanger is fabricated are such as to standardize as much as possible the shape, dimension, types of material and the like. This makes manufacturing as convenient and economical as possible yet allows great latitude in fabrication of a line of heat exchangers from a single basic design. For example, the plates and braze alloy sheets can be of generally flat rectangular shape and substantially the same dimension. Additionally, the flow and top and bottom plates can be of uniform and the same thickness, while the heat transfer plates will be of lesser thickness. Also the openings in the plates which define the passage networks are standardized as to location and size and the flow plates have a single configuration so that alternately arranged ones in the assembly have reversed orientation to alternately communicate the flow cavities to the respective two fluid passage networks. Further the turbulator members have a single size that allows their interchangeable reception in flow course openings in any of the assembly flow plates.
The turbulator members serve to present tortuous flow courses within the flow plates. This causes fluid turbulence flow conditions in the cavities such that film buildup on heat transfer surfaces as would materially effect desirable film coefficient values is avoided. Also, heat transfer is enhanced by exposing as much as possible the fluid to adjacent heat transfer surfaces. These turbulator members as noted can be of identical or different configuration. In one form, the turbulator members can be a grid of parallel rows of upstanding projections, i.e., be an alternating arrangement of peaks and valleys. The projections have alternately arranged at the sides thereof, a succession of laterally projecting abutment wings which present flow barriers requiring that striking fluid divert into openings at the sides of the wings to obtain on-flow access within the cavities. The rows of projections can be disposed either crosswise to or longitudinally of the flow cavities. The turbulator member projections can in another form, be of inverted channel section.
Because of the configurations of turbulators which can be selected for use in the heat exchanger, the turbulators can serve an additional important function in that they can constitute an extended heat transfer surface in each heat transfer cell thereby to increase the heat transfer capabilities of the heat exchanger for given heat exchanger dimensions. Increased heat transfer surface presence for a given heat exchanger cell dimension of as much as 40% or more is possible.
The heat exchanger can be used for cooling of and with various types of gases and liquids inclusive of air, refrigerants, lubricants, water etc. It possesses excellent heat transfer characteristics providing large heat transfer surface with minimized space requirements. Of particular advantage is that both hot and cold fluids can develop good film coefficients with overall coefficients two or three times those of shell and tube type heat exchangers.
The invention accordingly comprises the features of construction, combination of elements and arrangements of parts and steps as embodied in a heat exchanger which will be exemplified in the construction thereof and method for fabrication as hereinafter set forth and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will appear more clearly from the following detailed description taken in conjunction with the accompany drawings in which:
FIG. 1 is a side elevational view on reduced scale of a plate heat exchanger constructed in accordance with the principles of the present invention, the depicted embodiment being comprised of a plurality of heat transfer cells;
FIG. 2 is an exploded perspective view of a heat exchanger of the type shown in FIG. 1 but embodying only a single heat transfer cell therein, the turbulator members positioned in each of the flow cavities being of identically shaped configuration;
FIG. 3 is an exploded perspective view of a portion of a heat exchanger like that of FIG. 2 showing another turbulator configuration which can be used in the heat exchanger flow cavities;
FIG. 4 is a perspective view of another embodiment of turbulator member and depicts further the received positioning of such member in the flow plate that defines its associated flow cavity;
FIGS. 5 and 6 are respective fragmentary plan and right end elevational views of the turbulator members employed in the FIG. 2 heat exchanger;
FIGS. 7 and 8 are respective fragmentary plan and right end elevational views of the turbulator member shown in FIG. 4; and
FIG. 9 is a vertical sectional view on enlarged scale of the heat exchanger shown in FIG. 1 as taken along the cutting line IX--IX in FIG. 1, the embodiment shown being of a heat exchanger having five heat transfer cells.
Throughout the following description, like reference numerals are used to denote like parts in the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, there is depicted a plate heat exchanger 10 of the stacked plate type and which includes therein heat transfer cells 12 comprising in number as little as one and as many as fifteen cells, the cells each presenting heat exchange flow paths for a heated fluid and for a cooling fluid. FIGS. 2 and 3 illustrate the basic constructional makeup of the heat exchanger and as same incorporates but a single heat transfer cell. The arrangement of parts seen in FIGS. 2 and 3 are simply correspondingly duplicated in plural presence where it is desired to fabricate a plural heat transfer cell heat exchanger of greater heat exchanger capacity, e.g., the five heat transfer cell unit shown in FIG. 9.
Referring now to FIG. 2, heat exchanger 10 is comprised of elongated generally rectangular-shaped, flat plate members. The plate members stack in superposed relation one on the other and include a top plate 14, a bottom plate 16, the two flow plates 18H and 18C and heat transfer plate 20 which three plates together constitute a heat transfer cell 12. Braze alloy sheets 22 are shown intervening the top, bottom, flow plates and the heat transfer plate. These sheets are inserted in the stack during fabrication and provide the brazing alloy source material for joining together the unassembled plates.
Each flow plate 18H, 18C with the alternating heat transfer plate 20 defines a fluid flow course or flow cavity (the top and bottom plates in this respect also being heat transfer plates). The flow plates each have an elongated laterally widened flow course opening 26, such opening having diagonally disposed extensions as at 28 at its opposite ends, these extensions constituting flow inlet and outlet points communicating the defined flow cavity with a flow passage network as shall be described later. Disposed within each opening 26 is a turbulator member 30, the turbulator member having substantially regular plan outline and being sized to be slightly shorter than the run of the flow course opening 26 between its two end extensions 28. The turbulator member is of predetermined configuration selected from a plurality of different turbulator configurations available and related to type of fluid used therewith etc. and serves to present obstruction to flow within plates 18H, 18C thereby causing creation of irregular and random fluid flow currents. This effect is to enhance heat transfer from or to the fluid flowing in the cavity. In this regard and by reason of the particular finned turbulator configurations from which selection is made as well as the fact that the turbulator is connected in the assembly to the heat transfer plate, the turbulator additionally serves as an extended heat transfer surface so that the total heat transfer surface of the cell is considerably greater (for a given cell physical dimension) than that possible with prior types of heat exchangers.
The turbulator member 30 details of which are also shown in FIGS. 5 and 6, is a grid comprised of a plurality of parallel spaced rows 32 of upstanding projections, i.e., the grid presents alternating peaks and valleys which peaks and valleys will be, in the finished heat exchanger, secured or connected to the adjoining heat transfer plates by a braze alloy layer. The projections include a longitudinal succession of laterally directed abutment wings 34, the wings being located alternately at the two opposite sides of each row. The underside of each wing abutment is open and it is these openings which provide flow communication between the spaces or valleys at the two sides of each row. The turbulator can be positioned in the flow plates such that the rows 32 dispose transverse to the major axis or flow plate openings 26 and thereby present maximum abutment confrontation to fluid flowing through the flow plate. In such case, the flowing fluid will be forced to deviate laterally slightly in its course to enter the openings under the wings at one side of each row and also follow slight lateral deviation again to outlet from the wings at the other side of a row. The offset relationship of the wings 34 in each row can be seen with reference to FIGS. 5 and 6.
FIGS. 4, 7 and 8 show the same configured turbulator member 130 except in that embodiment, the rows 132 are disposed longitudinally of the flow course opening 26 of the flow course plate. This orientation of the turbulator provides less direct opposition to fluid flow since the wings 134 face crosswise to the flow direction and direct longitudinal flow courses exist in the spaces between the rows as at 133 and where the openings under each of the wings align as at 135, 137. The flow turbulence produced with this orientation is sufficient to effect good heat transfer while at the same time pressure loss through the cell is minimized.
FIG. 2 illustrates how the various plate components can be apertured or provided with openings to establish the two separate fluid flow passage networks present in the heat exchanger. The top plate 14, each braze alloy sheet 22 and heat transfer plate 20 are punched to have identically sized and located openings 40, 41 at an end thereof and a similar pair of openings 40a and 41a at the other end, the said openings being located each proximate a corner of its associated component. The flow plates 18H, 18C have a pair of diagonally opposed openings 42 which are located alongside of and isolated from the respective flow course extensions 28 in each such plate. With the plates in stacked and brazed assembly, the openings 40, 40a of the plates and the extensions 28 of the flow course plate 18H will register to constitute a heated fluid passage network extending between inlet to the heat exchanger defined by top plate opening 40a and the outlet defined by the top plate opening 40, the turbulator 30 in the flow cavity defined by flow plate 18H and heat transfer plate 20 and top plate 14 being located in such passage network. Threaded nipples IH and OH are brazed to the top plate and provide means for connecting the heat exchanger to the heated fluid origin. The same arrangement applies to the cooling fluid flow passage network wherein aligned openings 41, 41a and extensions 28 in plate 18C align to constitute the cooling fluid passage network, and it communicates with nipples IC and OC in the top plate. It will be appreciated that a variety of types of inlet and outlet arrangements for fluid flow to and from the heat exchanger are possible.
While the depicted heat exchanger construction involves countercurrent flow between the two fluids in the heat transfer cell, the same structure could also be employed if concurrent fluid flow is desired by simply connecting the inlets and outlets for the two fluids at corresponding ends of the heat exchanger. Various ways to provide multiple passes of either hot or cold side flow will be understood by those skilled in the art.
For fabrication of the heat exchanger no special or costly practice is involved. The bottom, top and flow plates can be of uniform and the same thickness, e.g., 12 gauge carbon or stainless steel plate stock. These plates, in a practical heat exchanger form, can be provided in sizes about 123/8 by 45/8 inches but in other convenient sizes as well. The various openings in the plates are made in a punching operation. The heat transfer plate can be made from the same carbon or stainless steel material but its thickness will while substantially uniform, be much less than that of the top, bottom or flow plates, e.g., about 1/10 inch. The braze alloy sheets, for example, and as is a common practice to this art, can be base metal with an overall surface cladding of an alloy material of any one of a number of such materials well known to those skilled in the art. The overall thickness of the braze alloy plates need only be several thousands of an inch.
In assembling a heat exchanger, the various plate components will be stacked as shown in FIG. 2, except that if plural heat transfer cells are to be embodied, the required numbers and alternating arrangement of additional flow and heat transfer plates will be used. In placing the plates in the stack, the assembler is guided by the readily visually discernible telltale margin notches 50 in the flow plates 18 so as to alternate these identically configured plates in reversed fashion in the stack to effect proper flow communication of each with its respective heated or cooling fluid passage network. The turbulator members used for a particular heat exchanger will of course depend on a particular use, type of fluid involved and cooling capacity required. The turbulator members will generally be fabricated in the grid shapes shown from carbon or stainless steel stock of about 0.005 to 0.010 inch thickness. The turbulators will have an overall height only slightly less than the thickness of the flow plates and are dimensioned lengthwise to be about 8 inches and have a width of about 4 inches.
When all of the plate components and turbulators as described above have been arranged in stacked assembly, the stack will be clamped and fittings IO, OC, IH and OH will be positioned on the top plate. The assembly will then be placed in an oven or like brazing environment to heat the assembly until the braze alloy sheets become molten sufficiently to effect connection joinder of the components as a unitary structure, with the spaces between the plates having fluid tight seal. Upon cooling, the assembly then is ready for testing and ultimate end use purpose. U.S. Pat. No. 4,006,776 is referred to as an example of a brazing procedure which can be used for this purpose. Other means of interconnecting the components such as welding also could be employed.
The FIG. 3 heat exchanger 110 is much the same as that shown in FIG. 2 except it reflects the use of a differently configured turbulator member. A turbulator member such as that shown in FIG. 2 would be used in one flow cavity of this embodiment whereas, the turbulator in the alternate cavity, i.e., turbulator member 230 would be comprised of a plurality of longitudinally directed parallel spaced fins 231, the turbulator fins each having the shape of an inverted channel member.
FIG. 9 shows how plural heat transfer cells are arranged in the heat exchanger, viz., a five cell unit. The five cells are designated 61-65 and the hot fluid passage networks in each by the letter h and the cold fluid passage networks by letter c.
From the foregoing description it will be understood that variations in the plate heat exchanger construction will occur to those skilled in the art and yet remain within the scope of the inventive concept disclosed. | A plate heat exchanger in which the various plates from which it is fabricated are brazed together in a stacked assembly comprised of flow plates and heat transfer plates arranged in alternating relationship. The heat exchanger has inlets and outlets for two fluids with passage networks extending between the inlets and outlets and turbulator members are located in each flow cavity formed between adjacent surfaces of the heat transfer and flow plates. The turbulator members are interchangeably positionable between each pair of adjacent flow and heat transfer plates and are selectable from a plurality of differently configured turbulator members. Plate sizes, shapes and openings therein are standardized to provide a basic heat exchanger system which can be fabricated in easily modified embodiments to meet various and diverse heat exchange requirements. | 5 |
SUMMARY OF THE INVENTION
The present invention relates generally to a two position, straight line motion actuator and more particularly to a fast acting actuator which utilizes pneumatic energy against a piston to perform extremely fast transit times between the two positions. The invention utilizes a pair of control valves to gate high pressure air to the piston and latching magnets to hold the valves in their closed positions until a timed short term electrical energy pulse excites a coil around a magnet to partially neutralize the magnet's holding force and release the associated valve to move in response to high pressure air to an open position. Stored pneumatic gases accelerate the piston rapidly from one position to the other position. During movement of the piston from one position to the other, intermediate pressure air fills a chamber applying an opposing force on the piston to slow the piston.
This actuator finds particular utility in opening and closing the gas exchange, i.e., intake or exhaust, valves of an otherwise conventional internal combustion engine. Due to its fast acting trait, the valves may be moved between full open and full closed positions almost immediately rather than gradually as is characteristic of cam actuated valves.
The actuator mechanism may find numerous other applications such as in compressor valving and valving in other hydraulic or pneumatic devices, or as a fast acting control valve for fluidic actuators or mechanical actuators where fast controlled action is required such as moving items in a production line environment.
Internal combustion engine valves are almost universally of a poppet type which are spring loaded toward a valve-closed position and opened against that spring bias by a cam on a rotating cam shaft with the cam shaft being synchronized with the engine crankshaft to achieve opening and closing at fixed preferred times in the engine cycle. This fixed timing is a compromise between the timing best suited for high engine speed and the timing best suited to lower speeds or engine idling speed.
The prior art has recognized numerous advantages which might be achieved by replacing such cam actuated valve arrangements with other types of valve opening mechanism which could be controlled in their opening and closing as a function of engine speed as well as engine crankshaft angular position or other engine parameters.
In copending application Ser. No. 021,195 entitled ELECTROMAGNETIC VALVE ACTUATOR, filed Mar. 3, 1987 in the name of WiIliam E. Richeson and assigned to the assignee of the present application, there is disclosed a valve actuator which has permanent magnet latching at the open and closed positions. Electromagnetic repulsion may be employed to cause the valve to move from one position to the other. Several damping and energy recovery schemes are also included.
In copending application Ser. No. 07/153,257, entitled PNEUMATIC ELECTRONIC VALVE ACTUATOR, filed Feb. 8, 1988 in the names of William E. Richeson and Frederick L. Erickson there is disclosed a somewhat similar valve actuating device which employs a release type mechanism rather than a repulsion scheme as in the previously identified copending application. The disclosed device in this application is a truly pneumatically powered valve with high pressure air supply and control valving to use the air for both damping and as the primary motive force. This copending application also discloses different operating modes including delayed intake valve closure and a six stroke cycle mode of operation.
Other related applications all assigned to the assignee of the present invention and filed in the name of William E. Richeson on even date herewith are Ser. No. 07/153,262 POTENTIAL-MAGNETIC ENERGY DRIVEN VALVE MECHANISM where energy is stored from one valve motion to power the next, and Ser. No. 07/153,154 REPULSION ACTUATED POTENTIAL ENERGY DRIVEN VALVE MECHANISM wherein a spring (or pneumatic equivalent) functions both as a damping device and as an energy storage device ready to supply part of the accelerating force to aid the next transition from one i5 position to the other. One distinguishing feature of the REPULSION ACTUATED POTENTIAL ENERGY DRIVEN VALVE MECHANISM application is the fact that initial accelerating force is partly due to electromagnetic repulsion somewhat like that employed in the first abovementioned copending application.
In the first two mentioned copending applications, numerous advantages and operating mode variations suitable for incorporation with the present valve actuator are disclosed and the entire disclosures of all four of these applications are specifically incorporated herein by reference.
In the present invention, the power or working piston which moves the engine valve between open and closed positions is separated from the latching components and certain control valving structures so that the mass to be moved is materially reduced allowing much faster operation than in the above two identified applications. Latching and release forces are also reduced. Those valving components which have been separated from the main piston need not travel the full length of the piston stroke, thus, less power is consumed in moving components.
Among the several objects of the present invention may be noted the provision of a bistable fluid powered actuating device characterized by extremely fast transition times; the provision of a pneumatically driven actuating device which is tolerant of variations in air pressure and other operating parameters; the provision of an improved electronically controlled pneumatically powered valve actuating device; and the provision of a pneumatically powered valve actuator where the control valves within the actuator cooperate with, but operate separately from the main working piston. These as well as other objects and advantageous features of the present invention will be in part apparent and in part pointed out hereinafter.
In general, a bistable electronically controlled fluid powered transducer has an armature including an air powered piston which is reciprocable along an axis between first and second positions along with a control valve reciprocable along the same axis between open and closed positions. A magnetic latching arrangement functions to hold the control valve in the closed position while an electromagnetic arrangement may be energized to temporarily neutralize the effect of the permanent magnet latching arrangement to release the control valve to move from the closed position to the open position. Energization of the electromagnetic arrangement causes movement of the valve in one direction along the axis allowing fluid from a high pressure source to drive the armature in the opposite direction from the first position to the second position along the axis. The distance between the first and second positions of the armature is typically greater than the distance between the open and closed positions of the valve.
Also in general and in one form of the invention, a pneumatically powered valve actuator includes a valve actuator housing with a piston reciprocable inside the housing along an axis. The piston has a pair of oppositely facing primary working surfaces. A pair of air control valves are reciprocable along the same axis relative to both the housing and the piston between open and closed positions. A coil is electrically energized to selectively opening one of the air control valves to supply pressurized air to one of the primary working surfaces causing the piston to move. The piston cooperates with the just opened air control valve upon sufficient piston motion to modify the air pressure differential across that air control valve causing the air control valve to reclose. Each of the air control valves includes an air pressure responsive surface which urges the control valve, when closed, toward its open position and there may be an air vent located about midway between the extreme positions of piston reciprocation for dumping expanded air from the one primary working surface and removing the accelerating force from the piston. The air vent also functions to introduce air at an intermediate pressure to be captured and compressed by the opposite primary working surface of the piston to slow piston motion as it nears one of the extreme positions and the air vent supplies intermediate pressure air to one primary working surface of the piston to temporarily hold the piston in one of its extreme positions pending the next opening of an air control valve. The air control valve is uniquely effective to vent air from the piston for but a short time interval after damping near the end of a piston stroke while supplying air to power the piston during a much longer time interval earlier in the stroke.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a view in cross-section showing the pneumatically powered actuator of the present invention with the power piston latched in its leftmost position as it would normally be when the corresponding engine valve is closed;
FIGS. 2-8 are views in cross-section similar to FIG. 1, but illustrating component motion and function as the piston progresses rightwardly to its extreme rightward or valve open position; and
FIGS. 9 and 10 compare air control valve behavior during the power stroke and damping blow-down.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawing.
The exemplifications set out herein illustrate a preferred embodiment of the invention in one form thereof and such exemplifications are not to be construed as limiting the scope of the disclosure or the scope of the invention in any manner.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The valve actuator is illustrated sequentially in FIGS. 1-8 to illustrate various component locations and functions in moving a poppet valve or other component (not shown) from a closed to an open position. Motion in the opposite direction will be clearly understood from the symmetry of the components. The actuator includes a shaft or stem 11 which may form a part of or connect to an internal combustion engine poppet valve. The actuator also includes a low mass reciprocable piston 13, and a pair of reciprocating or sliding control valve members 15 and 17 enclosed within a housing 19. The control valve members 15 and 17 are latched in one position by permanent magnets 21 and 23 and may be dislodged from their respective latched positions by energization of coils 25 and 27. The permanent magnet latching arrangement also includes iron pole pieces 20 and 22. The control valve members or shuttle valves 15 and 17 cooperate with both the piston 13 and the housing 19 to achieVe the various porting functions during operation. The housing 19 has a high pressure inlet port 39, a low pressure outlet port 41 and an intermediate pressure port 48. The low pressure may be about atmospheric pressure while the intermediate pressure is about 10 psi. above atmospheric pressure and the high pressure is on the order of 100 psi. gauge pressure.
FIG. 1 shows an initial state with piston 13 in the extreme leftward position and with the air control valve 15 latched closed. In this state, the annular abutment end surface 29 is inserted into an annular slot in the housing 19 and seals against an o-ring 31. This seals the pressure in cavity 33 and prevents the application of any moving force to the main piston 13. In this position, the main piston 13 being urged to the left (latched) by the pressure in cavity or chamber 35 which is greater than the pressure in chamber or cavity 37. In the position illustrated, annular opening 45 is in its final open position after having rapidly released compressed air from cavity 37 at the end of a previous leftward piston stroke. This rapid release is discussed in greater detail later in conjunction with FIGS. 9 and 10.
In FIG. 2, the shuttle valve 15 has moved toward the left, for example, 0.05 in. while piston 13 has moved toward the right perhaps half that distance and air at a high pressure now enters the annular cavity 37 from cavity 33 applying a motive force to the left face 38 of piston 13. The air valve 15 has opened because of an electrical pulse applied to coil 25 which has temporarily neutralized the holding force on iron armature or plate 47 by permanent magnet 21. When that holding force is temporarily neutralized, air pressure in cavity 33 which is applied to the air pressure responsive annular face 49 of valve 15 causes the valve to open. Notice that the communication between cavity 51 and the low pressure outlet port 41 has been interrupted by movement of the valve 15 before the valve clears the slot containing o-ring 31. This assures that no high pressure air escapes to the outlet port. It should also be noted that the edge of air valve 15 has overlapped the piston 13 at 53 closing annular opening 45 of FIG. 1 to assure rapid pressurization and maximum acceleration of the piston 13.
FIG. 3 shows the opening of the air valve 15 to about 0.10 in. (2/3 of its total travel) and movement of the piston 13 about 0.15 in. to the right. In FIG. 2, the high pressure air had been supplied to the cavity 37 and to the face 38 of piston 13 driving that piston toward the right. That high pressure air supply to cavity 37 is now cut off by the edge of piston 13 passing the annular abutment 55 of the housing 19. Piston 13 continues to accelerate, however, due to the expansion energy of the high pressure air in cavity 37. The right edge of piston 13 is about to cut off communication at 57 between the port 43 and chamber 35. Disk 47 is nearing the leftward extreme of its travel and is compressing air in the gap 61. This offers a damping or slowing effort to reduce the end approach velocity and consequently reduce any impact of the air valve components with the stationary structure. The annular surface 62 which is shown as a portion of a right circular cylinder may be undercut (concave) or tapered (a conical surface) to restrict air flow more near one or both extremes of the travel of plate 47 to enhance damping without restricting motion intermediate the ends.
The piston 13 is continuing to accelerate toward the right in FIG. 4 and the air valve 15 has just reached its maximum leftward open displacement. The valve will tend to remain in this position for a short time due to the continuing air pressure on the annular surface 49 from high pressure source 39. There is a bleeding of air between the annular air valve and the piston into chamber 63 which is rapidly decreasing the pressure differential across the air valve 15 and this will soon allow the magnetic attraction of the disk 47 by the permanent magnet 21 to pull the air valve 15 back toward its closed position. This air bleeding is complete and the motion apparent in FIG. 6. A wave washer or other spring may be located between the disk 47 and the end of housing 19 to both add to the damping provided by the air trapped in the end chamber 61 (FIG. 3) and to give a more rapid return of the air valve to the closed position if desired. In FIG. 4, the main piston 13 has just closed off communication between chamber 35 and medium pressure port 43 and further rightward motion of the main piston will compress the air trapped in chamber 35 so that the piston will be slowed and stopped by the time it has reached its extreme right hand position.
In FIG. 5, the air valve 15 is still in its extreme leftward position, but is just beginning to move toward the right to close the high pressure air port. For the first time, the main piston has cleared the edge of the valve 15 and high pressure air from source 39 is now applying a force against surface 65. This additional force on the piston 13 will continue so long as the valve remains open. The air valve is designed to close at about the same time as the main piston arrives at its furthest right hand location so the piston will experience this additional force during the remainder of its rightward movement. It has been found that this additional force on the piston helps to stabilize the damping of piston motion at the end of its travel and makes it much easier to adjust the intermediate pressure level at port 43 (and thus the initial pressure in cavity 35) to cancel any tendency for the main piston to bounce back prior to coming to rest at the right hand location. Also, in FIG. 5, the piston is continuing to compress the air in cavity 35 slowing its motion.
in FIG. 6, the air valve 15 is beginning to return to its closed position since all pressure around the valve has been neutralized and only the high attractive force of the magnet 21 on the disk 47 is causing the disk to move back toward the magnetic latch.
Further rightward movement of the piston as depicted in FIG. 6, uncovers the partial annular slot 67 leading to intermediate pressure port 43 so that the high pressure air in chamber 37 has blown down to the intermediate pressure. While the air valve has begun to close in FIG. 6, it is still open and the force of the high pressure air is still being applied to surface 65 helping to drive the piston toward the right and compress the air in chamber 35. In FIG. 6, the pressure in chamber 35 has reached a maximum and an annular opening is just beginning to form at 69 between the abutting corners of the piston 13 and air valve 17. This annular opening vents the high pressure air from chamber 35 just as the piston nears its right hand resting position to help prevent any rebound of the piston back toward the left.
It will be understood from the symmetry of the valve actuator that the behavior of the air control valves 15 and 17 in this venting or blow-down is, as are many of the other features, substantially the same near each of the opposite extremes of the piston travel. In each case, the air control valve, piston and a fixed portion of the housing cooperate to vent the damping air from the piston at the last possible moment while these same components cooperate at the beginning of a stroke to supply air to power the piston for a much longer portion of the stroke. Fragments of these components are shown in FIGS. 9 and 10 to better describe these two functions.
FIG. 9 illustrates the components in the same relative positions as in FIG. 2 while FIG. 10 depicts the components in the relative locations of FIG. 1. In FIG. 10, blow-down or dumping of damping air from the piston has taken place through annular opening 45 between the piston valve edge 97 and the extended porting edge 99. In FIG. 9, high pressure air is being supplied through the opening between the air valve 15 and the fixed porting edge 101 to the face 38 of piston 13 to drive the piston toward the right. It will be noted that the distance y in FIG. 9 which corresponds to the distance moved by the piston while air is being supplied to the face 38 is significantly greater than the distance x in FIG. 10 which is the piston travel during blow-down. This difference is achieved by moving or translating the effective porting edge back and forth during actuator operation.
The air valve 15 provides an extension at 99 of the fixed porting edge 101 when the air control valve is closed. This extension reduces the space (x in FIG. 10) between the piston valve edge 97 and the porting edge (now 99) so that the damping blow-down occurs during a very short time period from the narrow slot 45. However, when the air valve 15 is open, this extension is rendered inoperative allowing a larger closing distance (y in FIG. 9) between the piston valve edge 97 and the fixed porting edge 101 to assure a long power stroke. Thus, during leftward piston travel (FIG. 10), the distance (and therefore also the time) the piston travels while the port is open is considerably less than the length (and time) of piston travel toward the right while the port is open (FIG. 9).
The damping of the piston motion near its right extremity is adjustable by controlling the intermediate pressure level at port 43 to effectively control the density of the air initially entrapped in chamber 35. If this intermediate pressure is too high, the piston will rebound due to the high pressure of the compressed air in chamber 35. If this pressure is too low, the piston will approach it end position too fast and may mechanically rebound due to metallic deflection or mechanical spring back. With the correct pressure, the piston will gently come to rest in its right hand position. A further final damping of piston motion may be provided during the last few thousandths of an inch of travel by a small hydraulic damper including a fluid medium filled cavity 73 and a small piston 75 fastened to and moving with the main piston 13. Near either end of the main piston travel, the small piston 75 enters a shallow annular restricted area 77 displacing the fluid therefrom and bringing the main piston to rest. Fluid, such as oil, may be supplied to the damping cavity 78 by way of inlet 85.
in FIG. 7, the air valve 15 is nearly completely closed to shut off the high pressure air supply to chamber 63. The high pressure air continues to exert a force on face 65 of piston 13 which will tend to stabilize the damping of piston motion which is occurring in chamber 35. The pressure in chamber 35 is being relieved through the annular opening 79 and through the opening 81 and channel 83 to the low pressure port 41 so that the pressure throughout chambers 35 and 86 is reduced to nearly atmospheric pressure. Note that valves 15 and 17 include a number of apertures such as 93 and 95 in their respective web portions allowing free air flow between chambers 81 and 91 or 51 and 63. The piston 13 is reaching a very low velocity, the damping is almost complete and the final damping by the small fluid piston 75 is underway.
The main piston 13 has reached its righthand extreme in FIG. 8 and air valve 15 has closed off the supply of high pressure air from the source 39 to chamber 63. The respective annular openings 87 and 89 are venting chambers 63 and 35 to the low pressure port 41 and the piston is held or latched in the position shown by the intermediate pressure in chamber 37 from source 43.
In FIG. 1, which corresponds to a valve-closed condition, there is a slight gap between the piston face 38 and the valve housing while in FIG. 8 with the valve open, no such gap is seen. This gap provides for somewhat greater potential travel of the piston 13 than needed to close the engine valve insuring complete closure despite differential temperature expansions and similar problems which might otherwise result in the engine valve not completely closing.
Little has been said about the internal combustion engine environment in which this invention finds great utility. That environment may be much the same as disclosed in the abovementioned copending applications and the literature cited therein to which reference may be had for details of features such as electronic controls and air pressure sources. In this preferred environment, the mass of the actuating piston and its associated coupled engine valve is greatly reduced as compared to the prior devices. While the engine valve and piston move about 0.45 inches between fully open and fully closed positions, the control valves move only about 0.125 inches, therefore requiring less energy to operate. The air passageways in the present invention are generally large annular openings with little or no associated throttling losses.
From the foregoing, it is now apparent that a novel electronically controlled, pneumatically powered actuator has been disclosed meeting the objects and advantageous features set out hereinbefore as well as others, and that numerous modifications as to the precise shapes, configurations and details may be made by those having ordinary skill in the art without departing from the spirit of the invention or the scope thereof as set out by the claims which follow. | A bistable electronically controlled pneumatically powered transducer for use, for example, as a valve mechanism actuator in an internal combustion engine is disclosed. The transducer has an armature including a piston which is coupled to an engine valve, for example. The piston is powered by a pneumatic source and includes pneumatic and hydraulic damping as it nears its destination postion. The armature is held in each of its extreme positions by pneumatic pressure under the control of control valves which are in turn held in their closed postions by permanent magnet latching arrangements and are released therefrom to supply air to the piston to be pneumatically driven to the other extreme position by an electromagnetic arrangement which temporarily neutralizes the permanent magnetic field of the latching arrangement. | 5 |
BACKGROUND OF THE INVENTION
The invention relates to a power transmission unit with an input member and an output member and a hydraulic coupling dependent on a rotational-speed difference, in which, when a rotational-speed difference occurs between the input member and the output member, a hydrostatic displacement machine produces in a pressure space a pressure that acts on a piston acting on a friction clutch, the friction clutch having first and second disks connected in terms of drive to the input member and the output member respectively, and one of the members forming a housing that contains the displacement machine.
Power transmission units of this kind are used especially in drive trains of motor vehicles, preferably all-wheel-drive vehicles; either together with a differential, the hydraulic coupling limiting the differential action, or to drive the second driven axle, the torque transmitted depending on the difference between the wheel speed and the drive shaft connected to the wheels of the other axle. The pressure produced by the displacement machine acts on a clutch, preferably a multi-plate clutch. This action can be influenced by means of various valves, whether these are automatically acting valves or valves actuated by an external control system.
U.S. Pat. No. 5,536,215 has disclosed a power transmission unit of this kind, as has Austrian Utility Model 2964. In these and all such power transmission units, the pressure space in which the pressure acting on the piston is built up is in the rotating housing. As a result, the operating fluid contained in this housing is subject to a centrifugal force, which increases and thus distorts the pressure prevailing in the pressure chamber as a function of the rotational speed. This is particularly disruptive if the pressure is dependent on a rotational-speed difference and is supplied by a hydrostatic displacement machine, and this applies in both possible cases: if, in the first case—that of an unregulated coupling—there are no control valves, compensation is impossible; and if, in the second case, control valves intended to depressurize the pressure space for disengagement are provided, this is not possible at higher absolute rotational speeds because the discharge line adjoining the control valve has to end in a smaller radius. However, the pressure there is always less than in the pressure chamber, owing to centrifugal force.
It is therefore the object of the invention to eliminate these disadvantages corresponding to the special features of couplings of the generic type. The influence of centrifugal force should be at least partially compensated for to a necessary extent.
SUMMARY OF THE INVENTION
According to the invention, at least one centrifugal-force element is provided for this purpose in the housing, exerting on the piston a force that is the square of the rotational speed and acts counter to the pressure acting on the piston. By virtue of the fact that it is likewise situated in the housing, compensation to a specifiable extent is possible in all rotational-speed ranges without any outlay on regulation systems, given appropriate design. It is thereby possible to establish a speed dependence of the transmitted torque corresponding to the requirements as regards driving dynamics. The extent of compensation ranges from partial compensation and full compensation to overcompensation. In this arrangement, the transmitted torque falls as the speed increases, giving better traction at low speed and improved interaction with electronic brake systems (e.g. ABS) at high speed.
In an advantageous design, the at least one centrifugal-force element is a flyweight. Compensation of centrifugal force is thus performed in a purely mechanical way, and, in a preferred embodiment, the centrifugal-force element is part of a two-armed lever, one leg of which is the flyweight and the other lever of which is a pressure finger. The levers, of which there are three for example, are very simple and can be accommodated in the housing with only slight design changes. This is the simplest solution and can even be retrofitted to existing couplings.
The other design comprises the centrifugal-force element being an annular space that contains an operating fluid and rotates with the housing. This is a hydraulic method of compensating for centrifugal force. Since there is sufficient operating fluid in and around the coupling, there is no problem with supplying it.
In a first advantageous embodiment of this other design, the rotating annular space is formed by a cylindrical sleeve surrounding the housing and having a wall in the form of a circular ring normal to the axis and by a wall, normal to the axis, of the housing, and the sleeve is connected to the piston and can be displaced in an axial direction.
In this way, the annular space is bounded on one side by a displaceable wall and on the other side by a nondisplaceable wall of the housing. The liquid level in the annular space is determined by the inner radius of the wall in the form of a circular ring normal to the axis. The centrifugal force acting on the working medium in the annular space pushes apart the walls normal to the axis. This compensating force is transmitted to the piston by the displaceable sleeve.
In a second advantageous embodiment of this other design, the radially outermost zone of the rotating annular space is connected via a passage to a compensation pressure space on the opposite side of the piston from the pressure space. The annular space and the passage can also be provided within the housing. It is even possible, by means of valves associated with the passage, to achieve special effects in terms of driving dynamics.
A particularly elegant solution is for the compensation pressure space to be formed by an annular cylinder in the housing and by an annular continuation on the opposite side of the piston from the pressure space.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described and explained below with reference to figures, in which:
FIG. 1 shows a longitudinal section through a device according to the invention in a first embodiment,
FIG. 2 shows a longitudinal section through a device according to the invention in a second embodiment, and
FIG. 3 shows a longitudinal section through a device according to the invention in a third embodiment.
DETAILED DESCRIPTION
In FIG. 1 , the input member is denoted by 1 but it could also be the output member, to which a shaft 2 , indicated in broken lines, is flanged by means of bolts, which are merely indicated. It comprises a front plate 3 , an essentially cylindrical housing 4 , which is connected integrally or in a fixed manner to the front plate 3 , and an end plate 5 , which is connected releasably to the housing 4 for the purpose of assembly, though in a leaktight way. The output member 6 (it could also be the input member) is a hollow shaft, into which a shaft that is merely indicated is introduced by means of splines; it is supported in bearings 7 in the front plate 3 and the end plate 5 of the input member 1 and can be sealed off relative to the latter by means of seals 8 . Simple sealing rings are sufficient because the rotational-speed difference is very small on average. 9 denotes the axis of rotation or center line.
Within the housing 4 , there is a hydrostatic displacement machine 20 , which comprises an inner part 21 and an outer part 22 . The first of these is connected in a rotationally fixed manner to the output member 6 , while the second is connected to the input member 1 and, more specifically, to the housing 4 . The corresponding coupling teeth are merely indicated. Extending between the inner part 21 and the outer part 22 is a working space 23 , which is supplied via an intake passage 24 in a manner that is not shown. Adjoining the hydrostatic displacement machine 20 on the other side is an insert 25 , which contains a pressure passage 26 and a piston 27 , which is acted upon by the pressurized fluid supplied via the pressure passage 26 and, with the insert 25 , delimits a pressure space 34 . Some of this pressurized fluid can be directed into the space, which contains a clutch 31 , via a throttle valve 28 by a piston 27 , a number of inner plates 29 and outer plates 30 being arranged in said space. The first of these are connected to the output member 6 in a way that prevents relative rotation but allows translation, while the second are connected in the same way to the housing 4 of the input member 1 .
For the purpose of mounting a device for compensating the force exerted on the piston 27 by the centrifugal force in the pressure chamber 34 , the housing 4 here has a plurality of apertures 10 , which are distributed around the circumference and through which two-armed angled levers 12 reach. One leg of such a lever is constructed as a flyweight 11 , while the other is constructed as a pressure finger 13 , which engages in a recess 14 on the opposite side of the piston 27 from the pressure space 34 . Instead of a pivot passing through the two-armed lever 12 , a bearing edge 15 , on which a bearing shoulder 16 on the rear side of the pressure finger 13 is supported, is provided here on the aperture 10 in the housing 4 . This ensures that the lever 12 does not fly off. A projection 18 , which is held by an end stop 17 when the outermost permitted position of the flyweight 11 is reached, can be provided on the outermost end of the flyweight 11 .
FIG. 2 shows a different design. Here too, the housing 4 has a plurality of apertures 10 distributed around the circumference, through which radial pins 40 inserted into the piston 27 extend outward and are connected to a cylindrical sleeve 41 surrounding the housing 4 all the way round. They can transmit a force in the axial direction between the sleeve 41 and the piston 27 . The cylindrical sleeve 41 extends toward the left in the figure, projects beyond the housing 4 and ends in a wall 42 in the form of a circular ring normal to the axis. An annular space 44 is thus formed between this wall and a wall 43 , normal to the axis, of the housing 4 . This annular space is sealed off by means of a sealing ring 45 between the housing 4 and the sleeve 41 and contains working fluid to a level determined by the inside diameter of the wall 42 .
When the housing 4 is rotated, this liquid surface 46 becomes a cylindrical surface. During rotation, the centrifugal force in this annular space 44 gives rise to a pressure that pulls the wall 43 of the sleeve 41 to the left in the exemplary embodiment illustrated and thus, in turn, exerts on the piston 27 , via the pins 40 , a force that compensates for the centrifugal force in the pressure space 34 . The design and position of the annular space 44 can also be modified. The essential point is that an axial force counter to the force acting on the piston 27 in the pressure space 34 arises.
According to the variant in FIG. 3 , the connection between the annular space and the piston can also be established hydraulically. For this purpose, an annular space 50 is again provided, on the opposite side of the piston 27 from the pressure space 34 and within the housing 4 in the exemplary embodiment shown. The annular space 50 is kept filled from the interior of the clutch space via a feed hole 51 , a drain hole 52 ensuring that a constant (cylindrical) liquid surface 53 is maintained. The pressure produced by the centrifugal force in the annular space 50 acts via an axial passage 54 (or a plurality of such passages) on an annular cylinder 55 . This is likewise formed in the housing 4 and accepts an annular continuation 56 of the piston 27 in a sealing manner. With the annular cylinder 55 , it forms a compensation pressure space 57 . There, the pressure acts on the surface 58 in the form of a circular ring and thus compensates for the action of the pressure prevailing in the pressure chamber 34 .
It is possible to modify many details of the exemplary embodiments illustrated while remaining within the scope of the invention. Thus the construction of the hydrostatic displacement machine can vary very widely, both as regards the shape of its rotors and as regards their arrangement in the housing 4 . Finally, the power transmission unit can be arranged at various points within the drive train, in particular ahead of or after the axle differential in the power flow. It can also be arranged within a housing containing the axle differential. | A power transmission unit with a hydraulic coupling dependent on a rotational-speed difference, in which, when a rotationalspeed difference occurs between the input member ( 1 ) and the output member ( 6 ), a hydrostatic displacement machine ( 20 ) produces in a pressure space ( 34 ) a pressure that acts on a piston ( 27 ) acting on a friction clutch ( 31 ), has a housing ( 4 ). To compensate for the centrifugal force acting on the working fluid in the pressure space ( 34 ), at least one centrifugalforce element ( 11, 12, 13 ) is provided in the housing, exerting on the piston ( 27 ) a force counter to the pressure produced by the centrifugal force in the pressure chamber ( 34 ). | 5 |
TECHNICAL FIELD
[0001] The invention relates to a container for transporting, storing and dispensing hardwood charcoal.
CROSS REFERENCE TO RELATED APPLICATIONS
[0002] (Not applicable)
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0003] (Not applicable)
BACKGROUND OF THE INVENTION
[0004] Sixty thousand years ago, when men first began to cook food, it was done over open fires. Over the years, numerous innovations have been brought to the cooking of food. For example, in Roman times ovens, typically of stone and filled with a fire were used. The fire was set in the ovens for a long period of time to heat them up, after which the ashes were emptied, at least partially, to allow the introduction of bread or other items to be cooked.
[0005] Other societies, for example the aboriginal inhabitants of Hawaii, cooked food in a similar manner by digging a hole in the earth and heating up the surfaces of the hole through the use of burning wood. Following this, the item to be cooked was put into the hole, for example a whole animal, perhaps one in which the insides have been removed and replaced with accompaniments to the meat, such as vegetables, grains or the like.
[0006] An entirely different set of improvements to the cooking process involved the use of cooking vessels, typically copper, bronze, earthenware or the like which provided the advantage of containing the food being cooked, and containing the heat, perhaps through the use of a cover.
[0007] Both of these innovations resulted in minimizing the amount of fuel necessary to cook the food. More particularly, covering the vessel had the effect of preventing the escape of steam and the heat associated therewith. Likewise, containment of the food in a relatively small compartment of the vessel also reduced the area to be heated by the fuel, thus minimizing the amount of fuel necessary to cook the meal. Such innovations were of substantial importance. For example, in the relatively arid Fertile Crescent, fuel was in short supply due to the limited amount of vegetation. Indeed, even in comparatively lush geography, such as in England, wood was a precious commodity and laws regulated the use of this fuel resource. For example, in the English forest of the medieval period, it was legal for people to collect fallen branches in the forest, but the harvesting of live wood cut from trees was prohibited and punished.
[0008] Throughout the entire period of technological innovations and improvements, the cooking of food over a fire without a container or other cooking device has remained a popular option. Indeed, even the extremely convenient technologies of electric stove tops, electric ovens, microwave ovens, gas ovens, induction heaters, and the like have not remotely displaced the continuing practice of cooking food over an open fire.
[0009] No doubt, this is due to something more than a nostalgic or romantic connection to the past. This is in contrast to other areas of technology, where horses have been replaced by automobiles, handwork has been replaced by power tools, writing pens have been replaced by computers, and magazines and books have been replaced by tablets. No doubt, the continued strength of open fire cooking, typically practiced using charcoal briquettes or hardwood charcoal, is due to the superior process with which it cooks food, at least from the standpoint of taste.
[0010] Perhaps the closest approximation is the use of a propane grill which relies upon the item being cooked to release juices which fall upon heated steel or ceramic-like materials which cause it to burn, imparting something of the flavor of wood to the food being cooked. The use of dampened wood chips and the like with propane grills also contribute to making the flavor approach that of food cooked over an open wood fire. However, while propane grills have achieved great popularity, their performance still falls substantially short of hardwood charcoal.
[0011] In an effort to make the relatively inconvenient task of using charcoal more manageable and less troublesome, many innovations have been tried. Typically, and still overwhelmingly today, fuel for cooking is sold in the form of charcoal briquettes in a bag. In another context, fuel may be sold as split hardwood logs. Although the applications for the same are relatively limited, typically the realm of colonial cooking enthusiasts and the like, who have followed the colonial practices of hanging vessels over a fireplace, cooking cake in a Dutch oven nestled into ashes to prevent the cake from burning.
[0012] The present invention has as its object addressing the issues presented by prior art charcoal cooking apparatus and methods. More particularly, extensive efforts made by persons seeking to improve the cooking of food over an open fire have been to use manufactured briquettes whose uniform size allows them to be relatively easily poured out of a bag, for example one with a hole cut in the upper portion of a corner of the bag. The bag is then inverted and the coals are allowed to fall into the charcoal grill. While this technique has some advantages, it also has substantial disadvantages. More particularly, the bags of charcoal, when sold in economical sizes, are very large and difficult to handle and tend to bend over. They are also difficult to turn upside down to expel coal, especially when they are relatively full.
[0013] In an effort to address these issues, the use of rigid boxes for hardwood charcoal have long been recognized. However, these charcoal products tend to be of irregular shape, often elongated in shape and do not lend themselves to being poured from, for example, a paper bag. More particularly, pieces of this type of charcoal tend to interlock with other pieces of charcoal forming an interlocked mass. The only way to obtain a flow is to disrupt the interlocked mass. This can be done, for example, by shaking. However shaking a bag is relatively ineffective because of the free form formability of the bag causing it to tend to conform to the interlocked mass of hardwood charcoal in the bag.
[0014] Accordingly, the use of rigid containers has been proposed for containing hardwood charcoal. In connection with such efforts, the placement of the opening in the box has been proposed at the bottom of the container, insofar as this eliminates the need to turn the container over. See, for example, U.S. Pat. No. 6,357,653. However, this approach has a substantial flaw of resulting in making hardwood charcoal relatively difficult to fall. Accordingly, this approach has seen substantially no commercial use.
SUMMARY OF THE INVENTION
[0015] In accordance with the invention, it has been recognized that during shipment, hardwood charcoal will be shaken, causing the various pieces of charcoal to more securely interlock with each other. This complicates the interlocking which is built up as the charcoal bag is filled. Moreover, as the charcoal box is filled, the interlocking reinforces itself with upper layers interlocking with and supporting and improving the integrity of the interlocked mass as they add weight and add more structural interlocking elements. As a result, boxes with pour spouts on the bottom suffer from substantial difficulty during use.
[0016] In contrast, the present invention contemplates the use of a cardboard container, or container made of other material, having a size which is small enough to be easily picked up and inverted for emptying of charcoal through the opening on the top of the container. Moreover, the box is made with dimensions which promote the disintegration of the interlocked hardwood charcoal array matrix in the container. The use of relatively small containers in accordance with the invention goes against conventional wisdom which is biased in favor of large containers, due to the relatively low energy density of the typically used charcoal briquettes of the prior art.
[0017] The present invention has the advantage of promoting the use of hardwood charcoal which is environmentally superior due to its high energy density. More particularly, the same number of kilocalories of energy may be stored in relatively small boxes which may be easily moved and sufficiently provided to the consumer. Moreover, boxes of the size contemplated by the invention may be easily stacked in grocery store racks, and fit into shelves in conventional sizes while still providing the amount of energy needed to cook several meals. This dispenses with the necessity for the buyer to return, perhaps by car, to the point of sale to purchase more fuel, as would be the case with conventional low energy density charcoal briquettes. Moreover, while the packages are relatively small, they are not difficult to handle.
[0018] In accordance with the invention, the inventive cartridges containing charcoal are placed in numerous box sizes. However, the sizes take the form of boxes having specific dimensions for providing an easy to handle box shape and size while still providing flexibility in the amount of fuel being purchased. This may be of particular value to, for example, older persons or persons of relatively small strength to handle the inventive boxes in an appropriate size, while providing larger boxes of equally well proportioned size and configuration to enable persons of relatively greater strength to handle a large box and thus purchase in the single box a substantial amount of fuel. This reduces the need for packaging fuel in smaller quantities, but in multiple boxes. It also reduces the need to makes return trips to the store to load up on fuel repeated times.
[0019] In accordance with the invention, a cartridge for transporting, storing and dispensing hardwood charcoal is provided in a configuration which promotes easy handling and cartridge integrity and longevity.
[0020] The cartridge comprises a container having a height, a width and a depth for defining a volume. A cap is formed from a portion of a top portion of the container, and extends downwardly from the top of the container. A hinge portion joins the cap to the remaining portion of the top portion of the container. A quantity of hardwood charcoal is contained within the container.
[0021] The container may be a rectangular solid defined by a top surface, a bottom surface, a right side surface, a left side surface, a front surface, and a rear surface.
[0022] The cartridge container may be made of corrugated cardboard with the corrugations oriented to extend from the bottom to the top of the container. The top is formed from extensions of the corrugated cardboard forming the right side surface and the left side surface, whereby the corrugations forming the top are oriented extending from the right side surface to the left side surface.
[0023] The hinge portion may bend along a path substantially aligned with the corrugations in the corrugated cardboard forming the top.
[0024] The extensions of the corrugated cardboard forming the right side surface and the left side surface may overlie each other, and an extension of the front surface may extend between the top of the front surface and the hinge portion.
[0025] The cartridge height may vary between 10 inches and 18 inches, depth may vary between 10 inches and 18 inches, and width may vary in the range of 7 inches to 9 inches.
[0026] The ratio of the sum of the height and width to the depth may be in the range between 1 and 2.
[0027] Height may vary between 10 inches and 18 inches. Depth may vary between 10 inches and 18 inches. Width may vary in the range of 7 inches to 9 inches. The ratio of the sum of the height and width to the depth may be in the range between 1.25 and 1.95. The ratio of the sum of the height and width to the depth may be in the range between 1.7 and 1.8. The ratio of the sum of the height and width to the depth may also be in the range between 1.2 and 1.7.
[0028] The cap may be defined by a perforated path in the in the container, the perforated path extending partially around the periphery of the cap, the perforated path extending from a beginning point to an ending point and wherein the hinge portion extends between the beginning point and the ending point.
[0029] The container may have a cap comprising a) a roughly triangular member integral with said left side surface and separated from the remaining portion of said left side surface by perforations, b) a roughly triangular member integral with said right side surface and separated from the remaining portion of said right side surface by perforations, c) a roughly rectangular member integral with said top surface and separated from the remaining portion of said top surface by said hinge portion, and d) a roughly rectangular member integral with said front surface and separated from the remaining portion of said front surface by perforations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The operation of the inventive charcoal cartridge will become apparent from the following description taken in conjunction with the drawings, in which:
[0031] FIG. 1 is a perspective view of a hardwood charcoal loading cartridge illustrating a general implementation of the present invention;
[0032] FIG. 2 is a top plan view of a sheet of corrugated cardboard cut into a form for the assembly of the inventive hardwood charcoal loading cartridge;
[0033] FIG. 3 illustrates the embodiment of the hardwood charcoal loading cartridge of the present invention of FIG. 1 with the cap open for the discharge of hardwood charcoal;
[0034] FIG. 4 is a cross-sectional view along lines 4 - 4 of FIG. 1 of a hardwood charcoal loading cartridge according to the present invention;
[0035] FIG. 5 illustrates a graphic instruction printed on the inventive hardwood charcoal cartridge in accordance with the invention;
[0036] FIG. 6 is a perspective view of the inventive hardwood charcoal dispensing cartridge during the discharge of hardwood charcoal;
[0037] FIG. 7 is a perspective view of an alternative embodiment of the inventive hardwood charcoal dispensing cartridge in a size larger than the cartridge of FIGS. 1-6 ;
[0038] FIG. 8 is a top plan view of a sheet of cardboard cut to form the inventive hardwood charcoal dispensing cartridge illustrated in FIG. 7 ;
[0039] FIG. 9 is a top plan view of a sheet of cardboard cut to form the inventive hardwood charcoal dispensing cartridge in an intermediate or medium size; and
[0040] FIG. 10 is a top plan to different at the restaurant okay I have the set limit review them to is a paper there view of a sheet of cardboard cut to form the inventive hardwood charcoal dispensing cartridge in an extra small size.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0041] With reference to FIG. 1 , the inventive cartridge 10 comprises a left side 12 and a right side 14 . Referring to FIG. 2 , cartridge 10 has a depth 16 , a height 18 and a width 20 and is sized to enable comfortable handling and disentangling actions calculated to increase the flow of charcoal from the cartridge, as detailed below. In the embodiment illustrated in FIGS. 1 and 2 , the depth 16 of cartridge 10 may be made approximately 15.1 inches. Height 18 of cartridge 10 has a dimension of 11.1 inches. Width 20 has a dimension of 7.1 inches. Cartridge 10 has a capacity of 0.88 cubic feet.
[0042] As alluded to above with reference to FIG. 2 , the cartridge 10 of the present invention is made from a single sheet of cardboard member 22 , which may be either a single ply or a multiple ply corrugated cardboard having vertically oriented corrugations 23 , and a thickness of approximately ⅛ inch. Cardboard member 22 is assembled into cartridge 10 by incorporating a plurality of score lines 24 in the manner typical of prior art corrugated card manufacturer. In accordance with the invention, cardboard member 22 may be bent along vertical score lines 24 . Likewise, in conventional manner, flaps 26 and 28 may be bent upwardly along their respective horizontal score lines 24 . Structural integrity of cartridge 10 is provided, in part, by securing flaps 26 to each other along their length, after flaps 28 have been folded inwardly into the interior of the cartridge 10 . Further structural integrity is provided by gluing flap 30 to the periphery 32 of panel 34 .
[0043] Flaps 36 and 38 are then folded inwardly, followed by the folding in a flap 40 and then flap 42 . If desired, additional strength and ease of operation of the pouring orifice, as described below, may be obtained by gluing flap 36 to flap 40 . Moreover, additional strength can also be obtained by gluing flap 40 to top panel 44 .
[0044] In accordance with the invention, cardboard member 22 is provided with perforations 46 and 48 , which enable the formation of a pouring orifice 50 , by rotating a cap 52 upwardly, as illustrated in FIG. 3 . Such rotation is facilitated by score lines 54 . A notch to facilitate breaking perforations 46 and 48 may be formed by breaking perforation lines 58 and rotating at scoring 60 . Cap 52 has a height 62 of about four inches and a depth of about three inches.
[0045] The inventive cartridge 10 also has spaces for printing a product description 62 , graphic instruction 64 , logo 66 , and trademark 68 .
[0046] In accordance with the invention, cartridge 10 is filled to a height approximately 90% the height of the box with hardwood charcoal. By hardwood charcoal is meant charcoal made from hardwood species such as oak, or hickory or other hardwood charcoal with a density of very roughly about 9.3 pounds per cubic foot.
[0047] As alluded to above, the bottom of the cartridge may be taped closed, although glued construction or staples are preferred. In accordance with the invention, the bottom of the cartridge is of standard strength, while the top is of considerably greater strength, comprising multiple full layers of cardboard which may be glued or stapled, as described above, but being of slightly weaker construction at score line 54 to facilitate rotation of the cap 52 .
[0048] When it is desired to use the inventive cartridge 10 , cap 52 is formed by using a fingernail, key or tool to weaken or break perforations 46 and 48 . Notch 70 is then formed by pressing on flap 72 . This causes perforations 58 to break and the folding of flap 72 back along score line 60 . See FIGS. 1 and 3 . When notch 70 has been thus formed, the user may then pull cap 52 up and out, rotating along score line 54 and ripping perforation 48 then perforations 46 .
[0049] Cartridge 10 may then be rotated forwardly as shown in FIG. 6 to allow charcoal to be loaded into a grill from the inventive cartridge 10 . Handling may be facilitated by forming a hole for the fingers to grip by ripping perforations 78 and folding along score line 80 . This allows cartridge to be held simultaneously at the corner formed at the interface of the front face and bottom of cartridge 10 , and the hole formed by perforations 78 and score line 80 .
[0050] While specific cartridge dimensions are detailed above, some variation in the same may be implemented. However, depending upon objectives, in accordance with the invention, it has been discovered that maintenance of dimensional parameters within certain ranges provides substantial advantages. More particularly, in accordance with the invention, in the case of a right-handed person, the dimensions of the inventive cartridge 10 should be large enough for the left side 12 of cartridge 10 to fit comfortably against the right side of the torso of the person loading the charcoal into the grill with the right arm wrapped around right side 14 of cartridge 10 . In use, cartridge 10 may be cradled in the crook of the right elbow while the thumb bears against right side 14 of cartridge 10 . This allows for a stable maintenance of the position of the cartridge while also allowing the cartridge to be shaken to untangle the hardwood charcoal contained within cartridge 10 . In the case of a left-handed person, this configuration may be mirrored.
[0051] In accordance with a preferred embodiment of the invention, the ratio of the sum of the height 18 and width 20 to the depth 16 of the cartridge should be in the range between 1 and 2, preferably in the range between 1.25 and 1.95, and most preferably in the range between 1.7 and 1.8. Moreover for smaller persons, it has been discovered that the ratio of the sum of the height 18 and width 20 to the depth 16 of the cartridge is advantageously in the range between 1.2 and 1.7. Keeping these parameters within the above specification represents an optimal compromise between control, comfort and the provision of a sufficient quantity of hardwood charcoal in a cartridge.
[0052] Further in accordance with the invention it has been discovered that for the dispensing of hardwood charcoal, a particularly preferred hardwood charcoal dispensing cartridge is provided when height varies between 10 inches and 18 inches, and depth also varies between 10 inches and 18 inches, with width varied to accommodate the amount of hardwood charcoal which one wishes to load in a cartridge, preferably with width in the range of 7 inches to 9 inches and further provided that above ranges of the ratio of the sum of the height 18 and width 20 to the depth 16 are maintained. However, a particularly advantageous cartridge is provided when depth varies between 14 inches and 18 inches.
[0053] In accordance with the invention, a large cartridge 110 may be provided, as illustrated in FIGS. 7 and 8 . Cartridge 110 has a height of 16 inches, a depth of 16 inches and a width of 12 inches and can accommodate contents of 1.76 cubic feet. A cardboard member 122 to be formed into cartridge 110 , which is used and formed in the manner of the cartridge of the embodiment of FIGS. 1-6 is illustrated in FIG. 8 .
[0054] In accordance with the invention, a medium sized cartridge 210 may be provided, as illustrated in FIG. 9 . Cartridge 210 has a height of 16 inches, a depth of 16 inches and a width of 8 inches and can accommodate contents of 1.18 cubic feet. A cardboard member 222 to be formed into cartridge 210 , which is used and formed in the manner of the cartridge of the embodiment of FIGS. 1-6 is illustrated in FIG. 9 .
[0055] In accordance with the invention, an extra small cartridge 310 may be provided, as illustrated in FIG. 10 . Cartridge 310 has a height of 12 inches, a depth of 12 inches and a width of 8 inches and can accommodate contents of 0.66 cubic feet. A cardboard member 322 to be formed into cartridge 310 , which is used and formed in the manner of the cartridge of the embodiment of FIGS. 1-6 is illustrated in FIG. 10 .
[0056] The present invention contemplates the use of materials other than corrugated cardboard, and corrugated cardboard in various thickness. Moreover, cardboard that is not corrugated, as well as other materials such as substantially rigid plastic, wood and metal may be used to implement the inventive cartridge. Such cartridges may be made disposable, recyclable or reusable. For example, reusable cartridges may be made with their top panel secured in place by six screws, allowing the screws to be unscrewed and the top removed to allow the cartridge to be refilled, after which the top panel may be replaced into its original position, and then resecured in position with the screws.
[0057] While various embodiments of the invention have been described, it is understood that modifications within the spirit and scope of the invention may be made by those of skill in the art. Hardwood charcoal cartridges with such modifications are within the spirit and scope of the invention which is limited and defined only by the appended claims. | The inventive cartridge comprises a container having a height, a width and a depth for defining a volume. A cap is formed from a portion of a top portion of the container, and extends downwardly from the top of the container. A hinge portion joins the cap to the remaining portion of the top portion of the container. A quantity of hardwood charcoal is contained within the container. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention:
This invention relates to means for opening stopped up drains and the like.
2. Description of the Prior Art:
Prior methods and devices for opening stopped up drains have comprised three general proposals. First the introduction of a mechanical element into the drain so as to forcefully move or remove the stoppage. Two, the attempted introduction of a caustic material into the stopped up drain by pouring the same thereinto and three, the introduction of pressure both hydraulic and pneumatic so as to forcefully remove the stoppage.
The invention combines the best features of the prior art and introduces device for applying hydraulic and pneumatic pressure to the stopped up drain together with a charge of a caustic material which is injected thereby into the area of the stoppage by a device containing the caustic material and collapsible when in registry with the drain opening to create the hydraulic and pneumatic and injecting pressures necessary.
SUMMARY OF THE INVENTION
A device for clearing a stopped up drain is disclosed in which hydraulic and pneumatic pressure along with an injected charge of a caustic material are introduced into a stopped up drain through a drain opening communicating therewith by a collapsible container for the caustic material and acting as a pressure generating unit when manually collapsed while in registry with the drain opening.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded side elevation of a collapsible caustic container and dual closures therefor with parts broken away and parts in cross section,
FIG. 2 is a vertical section through a portion of a drain opening illustrating the force generating and material injecting action of the collapsible container of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In its simplest form the device for clearing a stopped up drain comprise uses the forceful introduction of a caustic agent such as lye into a drain opening along with a pressure surge, both hydraulic and pneumatic and the device comprises a collapsible container 10 preferably cylindrical having a closed bottom end 11 and an exteriorly threaded throat 12. A relatively wide annular collar 13 is formed exteriorly of the throat 12 and the body of the container 10 between the throat 12 and the closed lower end 11 takes the form of a plurality of bellow-like collapsible sections 14.
The body 10 of the container is formed of a flexible resilient synthetic resin such as polypropelene or the like and as illustrated in FIG. 1 of the drawings is normally filled with a caustic compound 15 such as lye in powder or flake form. A first sealing disc 16 preferably of aluminum, is sealed at its peripheral edge to the upper end of the throat 12 and a second closure comprising a threaded cap 17 is positioned thereover and engaged on the threaded throat 12 to form a satisfactory package for the caustic material.
It will thus be seen that a container for a caustic material such as lye has been disclosed which is doubly sealed so as to be safe in handling.
By referring now to FIG. 2 of the drawings, it will be seen that the container and the caustic material therein are shown in use in the herein disclosed method of clearing a stopped up drain and wherein a drain pipe 18 is shown in communication with a sink 19 or the like and the container 10 is shown inverted and positioned with its threaded throat 12 partially within the drain pipe 18 and the relatively wide collar 13 forming a closure with respect to the open end of the drain pipe 18.
In FIG. 2 of the drawings the container 10 will be seen to have been largely collapsed by force directed against its inverted bottom 11 as by the hand of the user so that the bellows-like sections 14 of the body 10 are collapsed to the point where the caustic material 15 has been forced through the aluminum sealing disc 16 which is broken and injected into the drain along with the caustic material where it is consumed thereby as the caustic material 15 reacts with and dissolves the stoppage blocking the drain pipe 18.
In addition to the introduction of the caustic material 15 the action of collapsing the container 10 as shown in FIG. 2 applies a hydraulic and pneumatic pressure surge to the stopped up drain pipe 18 with the combined result that the caustic material is injected into the area of the stoppage and the drain opened thereby.
It will thus be seen that a device for clearing a stopped up drain has been disclosed which may be inexpensively formed and safely used and will be effective under the circumstances described in view of the dual action of the pressure surge and injection of the caustic material which occur when the collapsible container is collapsed when in communication with the stopped up drain. It will occur to those skilled in the art that the present method and device will work very well when submerged in water in a sink bowl in communication with a stopped up drain associated therewith. | A device comprising a collapsible container having a throat configuration registrable with a drain opening and a frangible seal acting to open when the collapsible container is collapsed as in directing the caustic contents thereof into a stopped up drain. | 4 |
This application is a continuation of application Ser. No. 235,572, filed Feb. 18, 1981, abandoned.
BACKGROUND OF THE INVENTION
The field of the present invention is drive mechanisms for power boats. More specifically, the present invention is directed to mechanisms for transmitting power from an inboard motor of a power boat to a propeller.
A variety of mechanisms for providing power to a propeller for driving a boat have been employed, both successfully and unsuccessfully, since at least the 1800's. Two general categories of such devices employed with inboard motors have developed. Early on, fixed propeller shafts were developed which generally require a second mechanism, a rudder, for steering. More recently, devices known as inboard-outboards or stern drives have been developed which employ an articulated propeller shaft coupled with an inboard motor. These devices do not generally require additional steering mechanisms as the thrust from the propeller or propellers may be directed to effect steering much as a conventional outboard motor is employed.
Two mechanisms may be considered representative of the types of stern drives presently available. The first is illustrated in the North patent, U.S. Pat. No. 3,136,287. This device employs a horizontal input shaft, a vertical power transmission shaft, and a horizontal propeller shaft. This type of stern drive provides certain advantages of outboard motor flexibility and steering control. However, vertical shaft stern drives are typically rather inefficient because of the required gearing. The second type is represented by the Adams et al. patent, U.S. Pat. No. 3,933,116. This patent employs an inclined shaft from the inboard motor to an outboard, articulated propeller shaft. For reasons pointed out below, the engine disadvantageously must be placed low in the bilge, must be inclined and must be forward in the boat, particularly if gearing is required.
Coincident with the development of power trains for boats, improved propeller performance has also been achieved. To date, it is understood to be beneficial to run the propeller of high speed, competition type boats only about 55% submerged in the water. It is also believed to be beneficial to have the axis of the propeller angled downwardly relative to the keel line by a maximum of about two to three degrees. Finally, a factor affecting the overall performance of the propeller and the hull is to have a relatively low center of thrust. Because of these desirable factors for high speed performance, the inboard motor of the Adams et al. device must be located low, at an angle, and as far forward as possible. The North type stern drive is better able to accomplish a desired propeller orientation. However, as mentioned above, substantial efficiency is lost in the power train.
SUMMARY OF THE INVENTION
The present invention is directed to a power train for a boat having an inboard motor and a stern drive propeller. The invention includes a gear box located exterior to the hull for achieving the proper propeller attitude relative to the hull without the inefficiency of circuitous drive train lengths. This result accomplished by the present invention is achieved through the employment of an outboard gear box having parallel shafts each positioned in a generally horizontal orientation and being positioned relative to one another in a generally vertical arrangement, the lowermost of the shafts being the output shaft. A companion case dealing with the same stern drive system is disclosed in an application filed concurrently herewith to John A. Conner entitled STERN DRIVE, Ser. No. 235,573, filed Feb. 18, 1981, now U.S. Pat. No. 4,565,532, the disclosure of which is incorporated herein by reference.
The arrangements contemplated by the present invention do not achieve the appropriate orientation of the propeller shaft at the expense of inboard motor placement. Instead, the present system improves the placement of the inboard motor by allowing it to be positioned as far aft as the inboard side of the transom. It is also contemplated that the inboard position of the motor will be substantially horizontal relative to the hull and may be located up out of the bilge. In spite of this more advantageous placement of the inboard motor, the center of thrust is located low in the stern and is not tending to force the stern up and bow down.
The devices contemplated by the present invention also may enjoy other advantages. The outboard location of the gear box removes the gear box from the relatively stagnant, heated environment of the engine compartment and places it in a position to receive both water and air cooling.
Accordingly, it is an object of the present invention to provide an improved drive train for a stern drive. Other and further objects and advantages will appear hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of an embodiment of the present invention shown positioned on a boat. The hull has been partially sectioned for clarity of illustration.
FIG. 2 is a side view of the embodiment of FIG. 1 with the boat hull sectioned along line 3--3.
FIG. 3 is a cross-sectional elevation taken along line 3--3 of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning in detail to the drawings, FIGS. 1 and 2 illustrate the arrangement of an embodiment of the present invention in association with a hull 10. The hull 10 includes a transom 12. The hull illustrated in FIG. 1 may represent either of two configurations. The first configuration would be that of a small boat wherein the drive is positioned centrally in the hull. In a second configuration, the portion of the hull illustrated may simply be the port side thereof. In such an event, a link, shown in phantom as 14, may be employed to control a second stern drive located on the starboard side of the hull.
Located inboard within the hull 10 is an inboard motor 16. Consistent with this preferred embodiment of the present invention, the inboard motor 16 is illustrated as being horizontally disposed relative to the hull 10 and positioned well out of the bilge. A hole 17 provides access between the motor and the stern drive.
A gear box, generally designated 18, is securely positioned to the outboard side of the transom 12. The gear box 18 includes a gear box housing 20 which is generally configured in a functional manner to enclose the drive train and to provide structural support for the articulated propeller shaft housing. The gear box 18 is held to the transom 12 by conventional means such as bolts. The bolts are distributed about the gear box housing 20 for optimum support and sealing with the transom 12. Where necessary, such as at location 22, clearance is made for facile placement of the bolts. The housing 20 generally includes a flange 24 which receives the fastening means.
Located aft of the gearbox 18 is a propeller shaft housing 24. The propeller shaft housing 24 includes an input shaft 26 and an output shaft 28. Together the input shaft 26 and the output shaft 28 combine to form a propeller shaft assembly. A gear pair consisting of gear wheels 30 and 32 couple the propeller shafts 26 and 28 together. The input propeller shaft 26 is mounted at a first end by a ball bearing 34 and at a second end by a roller bearing 36. The ball bearing 34 is retained by a shoulder 38 and a split ring retainer 40. A spacer 42 and another split ring retainer 44 retain the gear wheel 30 in position. The gear wheel 30 is caused to rotate with the shaft 26 by means of a coupling with splines 46.
The output propeller shaft 28 is rotatably mounted in the propeller shaft housing 24 by means of two ball bearings 48 and 50. The gear wheel 32 is held in place on the shaft 28 by means of a spacer 52 and a split ring retainer 54. Splines 56 insure coupled rotation of the gear wheel 32 with the shaft 28. At the distal end of the output propeller shaft 28, it is rotatably mounted in the propeller shaft housing 24 by a roller bearing 58. A plurality of seals 60 protect the distal end of the propeller shaft housing 24 from water intrusion. A cap 62 and a split ring retainer 64 retain the seals and bearing in position. A propeller 66 is conventionally mounted to the end of the propeller output shaft 28.
The gear pair provided by gear wheels 30 and 32 are employed in the propeller shaft housing 24 to lower the center of thrust of the stern drive without inducing further angular offset with the keel line. At the location where the gear pair is arranged, less drag is encountered than if the gearbox 18 were to be positioned such that it extended below the bottom of the transom 12. Thus, improved propeller performance is achieved with out substantially increasing the drag of the stern drive in the water.
Naturally, the propeller shaft housing 24 is configured as narrow as possible about the gear pair located therein. The propeller shaft housing 24 is split in a plane substantially normal to the axis of the propeller drive. Fasteners 68 are employed to retain the two portions of the propeller shaft housing 24 together and sealed.
The propeller shaft housing 24 is fixed to a mount 70 which, in this embodiment, is formed as an integral part of the gearbox housing 20. If no gearbox is employed, the mount 70 may be directly affixed to the transom 12. Coupled to the mount 70 is a mounting means for retaining the propeller shaft housing 24 yet allowing the housing 24 universal pivotal motion such that the propeller shaft housing 24 may be pulled up out of the water or extended down further into the water or may be pivoted laterally for steering. Appropriate portions of the mount 70 and the propeller shaft housing 24 are cut away to provide the necessary clearance for such movement. The mounting means includes in this preferred embodiment of a gimbal ring 72. Gimbal lugs are formed on each of the mount 70 and the propeller shaft housing 24 to receive gimbal pins of the gimbal ring 72. The gimbal lugs are split and include lug caps 76 on both the mount 70 and the propeller shaft housing 24.
The propeller shaft housing 24 is gimbaled to the mount 70 concentrically about a coupling means for transmitting power from the output shaft 78 to the propeller input shaft 26. This coupling means accommodates a range of colinear and non-collinear orientations of the two shafts and, in the present embodiment, is provided by a universal joint generally designated 80. The universal joint 80 is directly coupled to both the output 78 and the propeller input shaft 26 in a conventional manner.
To protect the gimbal 72 and the universal joint 80, it is contemplated that a boot (not shown) be positioned in sealed engagement with the mount 70 and extending into a similar sealed engagement with the propeller shaft housing 24. In this way, moisture can be excluded from the area of both the mounting and coupling means for the gimbaled propeller shaft. The boot, of course, requires substantial flexibility to accommodate the gimbaled motion of the propeller shaft housing 24.
Steering and attitude control mechanisms are associated with the propeller shaft housing 24 by a boss 82 on the upper side of the propeller shaft housing 24. A control bracket 84 is pivotally mounted on the boss 82 by means of a clevis and spherical joint assembly 86. To this control bracket 84 are coupled an attitude control hydraulic cylinder 88 and a steering control hydraulic cylinder 90. Also link 14 may be coupled with the control bracket 84 when a dual stern drive arrangement is employed. The steering cylinder 90 is then fixed by means of a conventional mount 92 to the transom 12. The attitude cylinder 88 is coupled to a plurality of mounting brackets 94 located on the upper portion of the gearbox housing 20. Thus, the gimbaled propeller may be controlled in all directions by conventional hydraulics.
On the propeller shaft housing 24 are fins available for further control. A dorsal fin 94 extends upwardly to a horizontal propeller guard 96. A skeg 98 extends downwardly from the main portion of the propeller shaft housing.
Thus, an improved stern drive arrangement is here disclosed. | A drive mechanism for power boats having an inboard motor and a stern drive propeller mounting. The device includes a gimbaled propeller shaft housing located outboard of the transom. A gear pair mounted within the propeller shaft housing provides a lower propeller shaft relative to the hull of the boat without requiring a greater propeller shaft angle relative to the hull and without requiring a lowered inboard motor position. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The application is a continuation of application Ser. No. 10/586,462 filed on Jul. 14, 2006. This application is the US National Stage of International Application No. PCT/EP2005/000223, filed Jan. 12, 2005 and claims the benefit thereof. The International Application claims the benefits of European Patent application No. 04001107.4 filed Jan. 20, 2004. All of the applications are incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
[0002] The invention relates to a turbine blade with a blade leaf arranged along a blade axis and with a platform region, which, arranged at the foot of the blade leaf, has a platform extending transversely with respect to the blade axis. The invention applies, furthermore, to a gas turbine with a flow duct extending along an axis of the gas turbine and having an annular cross section for a working medium, and a second blade stage arranged downstream of a first along the axis, a blade stage having a number of annularly arranged turbine blades extending radially into the duct.
BACKGROUND OF THE INVENTION
[0003] In a gas turbine of this type, temperatures which may lie in the range of between 1000° C. and 1400° C. arise in the flow duct after it has been acted upon by hot gas. The platform of the turbine blade, as a result of the annular arrangement of a number of such turbine blades in a blade stage, forms part of the flow duct for a working fluid in the form of hot gas which flows through the gas turbine and thereby drives the axial turbine rotor by the turbine blades. Such high thermal stress on the flow duct boundary formed by the platforms is counter-acted in that a platform is cooled from the rear, that is to say from a turbine blade foot arranged below the platform. For this purpose, the foot and the platform region conventionally have suitable ducting so as to be acted upon by a cooling medium.
[0004] An impact-cooling system for a turbine blade of the type initially mentioned may be gathered from DE 2 628 807 A1. In DE 2 628 807 A1, for cooling of the platform, a perforated wall element is arranged upstream of that side of the platform which faces away from the hot gas, i.e. downstream of the platform, that is to say between a blade foot and the platform.
[0005] Cooling air under relatively high pressure impinges through the holes of the wall element onto that side of the platform which faces away from the hot gas, with the result that efficient impact cooling is achieved.
[0006] EP 1 073 827 B1 discloses a novel way of designing the platform region of cast turbine blades. The platform region is designed as a double platform consisting of two platform walls lying opposite one another. What is achieved thereby is that the platform wall directly exposed to the flow duct and therefore to the hot gas and delimiting the flow duct can be made thin. The design in the form of two platform walls results in functional separation for the platform walls. The platform wall delimiting the flow duct is responsible essentially for the ducting of hot gas. The opposite platform wall not acted upon by the hot gas takes over the absorption of the loads originating from the blade leaf. This functional separation allows the platform wall delimiting the flow duct to be made so thin that the ducting of the hot gas is ensured, without substantial loads in this case having to be absorbed.
[0007] In the design of the turbine blade of the type initially mentioned, in a parting plane between platforms of turbine blades of the same blade stage which are contiguous or of adjacent turbine blades of blade stages arranged one behind the other, sealing measures are necessary in order to prevent an unwanted and excessive outflow of cooling medium into the flow duct acted upon by hot gas. The measures required for sealing off may lead to difficult situations in structural and cooling terms on a platform wall subjected to high thermal load and constitute an increased potential for the failure of a turbine blade and consequently of a gas turbine.
[0008] Conventionally, the sealing off of such parting planes is achieved by the installation of special sealing elements. However, on the one hand, these have to be sufficiently flexible to permit simultaneous relative movements of adjacent parts, in particular of adjacent turbine blades and their platforms, and, on the other hand, they must nevertheless maintain a sealing action. The installation of such sealing elements leads to geometrically and structurally complicated components. As a result of this, special cooling measures are necessary so that platform edge regions where access is difficult can be cooled sufficiently.
[0009] It would be desirable to have a gas turbine in which the boundary of the flow duct is configured as simply as possible and at the same time can be cooled effectively and is sealed off.
SUMMARY OF THE INVENTION
[0010] This is where the invention comes in, the object of which is to specify a turbine blade with a platform, which at the same time is configured in a simple way and also advantageously satisfies the geometrically structural and cooling requirements within the framework of a flow duct boundary of a gas turbine. Furthermore, the sealing off of the parting planes between adjacent turbine blades is to take place particularly simply and cost-effectively.
[0011] As regards the turbine blade, the object is achieved by the invention by means of the turbine blade initially mentioned, in which, according to the invention, the platform is formed at least partially by a first resilient elastic sheet metal part which is fixed to the blade leaf and which can be laid against an adjacent turbine blade.
[0012] The invention proceeds from the consideration that the use of a platform which is not load-bearing for forming the boundary of a flow duct, acted upon by hot gas, of a gas turbine is fundamentally suitable for cooling the platform and consequently the boundary of the flow duct as effectively as possible. Beyond this, the essential recognition of the invention is that it is possible to equip the platform itself with an increased sealing action, specifically in that the platform is made thin-walled such that it is formed by a resilient elastic sheet metal part lying against the blade leaf.
[0013] To be precise, the platform, as a part delimiting the flow duct acted upon by hot gas, consequently fulfills all the requirements in terms of cooling and also of a sealing element. By resilient elastic sheet metal part being fixed to the blade leaf, to be precise, the platform as such is sufficiently flexible to permit simultaneous relative movements of adjacent blade leaves and of other parts, and nevertheless maintains the sealing action. This avoids the need for a special sealing element. This simplifies the configuration and cooling of the flow duct boundary.
[0014] According to the invention, the first resilient elastic sheet metal part is provided as a platform wall which is not load-bearing, which at least partially delimits the flow duct acted upon by hot gas. A load-bearing platform wall provided in EP 1 073 827 B1, which would be arranged downstream of the first resilient elastic sheet metal part, may largely be dispensed with. The platform therefore consists at least partially of the first resilient elastic sheet metal part fixed to the blade leaf.
[0015] The sealing element necessary hitherto between platforms of adjacent turbine blades may be dispensed with, since the first resilient elastic sheet metal part of one turbine blade lies sealingly against the other adjacent turbine blade.
[0016] The advantages as regards the cooling and sealing action of the first resilient elastic sheet metal part for the platform and consequently the flow duct boundary are preserved.
[0017] Advantageous developments of the invention can be gathered from the subclaims and specify in detail advantageous possibilities, in particular, for developing the platform in terms of the above object.
[0018] According to a particularly preferred development of the invention, there is provision for the platform to be formed by the first resilient elastic sheet metal part fixed to a first abutment on one side of the blade leaf and to be formed by a second sheet metal part fixed to a second abutment on the other side of the blade leaf. Consequently, two sheet metal parts are expediently provided, which form the platform and which therefore extend on both sides transversely with respect to the blade axis on one side of the blade leaf and the other.
[0019] Expediently, the second sheet metal part lying against the blade leaf assumes the function of a first platform wall not bearing the load of the blade leaf, and, furthermore, the platform has a second platform wall bearing the load of the blade leaf. In this refinement, appropriate cooling space for acting upon by cooling medium is formed between the first platform wall which is not load-bearing and which consists of the second sheet metal part and the second thicker load-bearing platform wall, as a special load-bearing structure.
[0020] According to a development of the invention, each abutment may be designed in the form of a groove or edge. This allows a particularly reliable and fluidically beneficial fastening of the sheet metal part to the foot of the blade leaf.
[0021] Within the scope of a preferred development of the invention, it has proved expedient for the sheet metal parts, in particular the first, to be held at a further abutment of an adjacent turbine blade. Expediently, this further abutment may be in the form of a bearing support.
[0022] For example, such a bearing support may be formed by a step integrally formed between the blade foot and the foot of the blade leaf. The first sheet metal part of a first turbine blade engages sealingly behind the bearing support of the turbine blade adjacent to this. The second sheet metal part may advantageously engage behind the bearing support arranged on the same turbine blade or, additionally or alternatively, may be attached to the step.
[0023] Expediently, in the state of rest, the first resilient elastic sheet metal part lies loosely against the further abutment of the adjacent turbine blade. In this case, a sufficient fastening, yet to be explained, of the sheet metal part arises from the movement or fluidic tie-up of the turbine blade in the operating state of a gas turbine.
[0024] The sealing action of the first resilient elastic sheet metal part on the further abutment may be further improved if the first resilient elastic sheet metal part lies against the further abutment under a self-generated prestress.
[0025] Furthermore, to achieve the object, the invention applies to a gas turbine mentioned initially, a blade stage having a number of annularly arranged turbine blades extending radially into the flow duct, in accordance with the invention a turbine blade being designed according to an abovementioned type.
[0026] Advantageous developments of the gas turbine may be gathered from the further subclaims and specify in detail advantageous possibilities, in particular, for designing the flow duct boundary and the function of the turbine blade within the framework of the flow duct boundary in accordance with the above object.
[0027] Within the framework of a first development, the turbine blade is a moving blade. Such a moving blade is fastened to an axially extending turbine rotor and rotates together with the turbine rotor during operation of the gas turbine. During the rotary operation of a turbine blade in the form of a moving blade on the turbine rotor, a centrifugal force acting from the foot of the blade leaf in the direction of the blade leaf is generated as a result of rotation. In this case, according to the development, the first resilient elastic sheet metal part achieves a sufficient sealing action between two mutually contiguous sheet metal parts of two adjacent moving blades. As a result of the centrifugal force, the first resilient elastic sheet metal part of a first moving blade is pressed against a further abutment of the second moving blade and is thereby laid in place, fastened by centrifugal force. That is to say, even in the event that the first resilient elastic sheet metal part lies loosely against the further abutment in the state of rest of the moving blade, the centrifugal force ensures that the resilient elastic sheet metal part lies sealingly against the moving blade in the operating state. When the moving blade of the gas turbine is in operation, the first resilient elastic sheet metal part thus also has the function of a sealing element. In this case, the lying surface of the first resilient elastic sheet metal part against the further abutment of the adjacent moving blade in the form of a bearing support advantageously acts as a sealing abutment for the first metal part. The penetration of hot gas flowing through the turbine through the gap formed hitherto between two platforms of adjacent moving blades can be avoided on account of the effective seal, as can an undesirably high leakage of coolant through the gap into the hot-gas space.
[0028] According to an alternative development of the gas turbine, the turbine blade is provided as a guide blade on the peripheral turbine casing. During the operation of a turbine blade in the form of a guide blade on the turbine casing, a pressure drop is generated by a cooling medium from the foot of the blade leaf in the direction of the blade leaf. In this case, the alternative development provides for the first resilient elastic sheet metal part of a first guide blade to be pressed due to the pressure drop against the further abutment of a second guide blade and thereby to be fastened by pressure. The pressure drop is thus generated in that the first resilient elastic sheet metal part is acted upon from the rear by cooling medium and is thereby pressed against the further abutment. For a guide blade, the pressure drop is sufficiently high, so that this not only suffices for a pressure fastening of the first resilient elastic sheet metal part against the further abutment, but, furthermore, when the guide blade in the gas turbine is in operation, the first resilient elastic sheet metal part, has the function of a sealing element. The lying surfaces of the first resilient elastic sheet metal part act as sufficient sealing surfaces at an abutment explained above, and the abutment acts as an abutment for the first resilient elastic sheet metal part.
[0029] Within the framework of a refinement of the gas turbine, it proves advantageous that a flow duct boundary is continuously formed, between a first turbine blade and an adjacent second turbine blade of the same blade stage, by a first resilient elastic sheet metal part of the first turbine blade and by a second sheet metal part of the second turbine blade. Within a blade stage, a continuous radial boundary of the flow duct is thereby advantageously formed.
[0030] Within the framework of a further refinement of the gas turbine, it proves advantageous, furthermore, that a flow duct boundary is continuously formed, between a first turbine blade of the first blade stage and a second turbine blade of the second blade stage axially adjacent to the first turbine blade with respect to the rotor, by a first resilient elastic sheet metal part of the first turbine blade and by a second sheet metal part of the second turbine blade. A continuous boundary of the flow duct is thereby advantageously formed. Advantageously, the blade stages are guide blade stages and the turbine blades are guide blades.
[0031] Because of, the abovementioned types of continuous boundary, the parting planes, otherwise to be sealed off in the case of conventional boundaries of a flow duct of a gas turbine, and the then additionally required sealing elements are expended. The problems arising in connection with sealing elements are eliminated entirely on account of the continuous delimitation of the flow duct by means of the first resilient elastic sheet metal part and the second sheet metal part.
[0032] In this case, it proves expedient that a first resilient elastic sheet metal part arranged on a first turbine blade and a second sheet metal part arranged on a second turbine blade are held jointly at the further abutment of the first turbine blade. Details are explained in connection with the drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] A particularly preferred exemplary embodiment of the invention is described below with reference to the drawing. This is not intended to illustrate the exemplary embodiment true to scale, on the contrary the drawing, where appropriate for an explanation, is in diagrammatic and/or slightly distorted form. As regards additions to the teachings which can be seen directly from the drawing, reference is made to the relevant prior art. In particular, in the drawing:
[0034] FIG. 1 shows a particularly preferred embodiment of a gas turbine with a flow duct and with a preferred version of the guide and moving blading in diagrammatic form in a cross-sectional view;
[0035] FIG. 2 shows a platform region of a particularly preferred embodiment of a first turbine blade of a first blade stage and of a second turbine blade, axially adjacent to the first turbine blade, of a second blade stage, in a perspective view.
DETAILED DESCRIPTION OF THE INVENTION
[0036] FIG. 1 shows a gas turbine 1 with a flow duct 5 extending along an axis 3 and having an annular cross section for a working medium M. A number of blade stages are arranged in the flow duct 5 . In particular, a second guide blade stage 9 is arranged downstream of a first guide blade stage 7 along the axis 3 . Furthermore, a second moving blade stage 13 is arranged downstream of a first moving blade stage 11 . The guide blade stages 7 , 9 in this case have a number of guide blades 21 arranged annularly on a peripheral turbine casing 15 and extending radially into the flow duct 5 . A moving blade stage 11 , 13 in this case has a number of moving blades 23 arranged annularly on an axial turbine rotor 19 and extending radially into the flow duct 5 . The flow of a working medium M is in this case generated in the form of a hot gas by a burner 17 . Correspondingly to the annular cross section of the flow duct 5 , a number of such burners 17 are arranged around the axis 3 in an annular space not shown in the cross-sectional drawing of FIG. 1 .
[0037] A guide blade 21 and a moving blade 23 are shown diagrammatically in FIG. 1 . A guide blade 21 has a blade tip 27 arranged along a blade axis 25 , a blade leaf 29 and a platform region 31 . The platform region 31 has a platform 33 extending transversely with respect to the blade axis 25 and a blade foot 35 .
[0038] A moving blade 23 has a blade tip 37 arranged along a blade axis, a blade leaf 39 and a platform region 41 . The platform region 41 has a platform 43 extended transversely with respect to the blade axis 45 and a blade foot 47 .
[0039] The platform 33 of a guide blade 21 and the platform 43 of a moving blade 23 thus form in each case part of a boundary 49 , 51 of the flow duct 5 for the working medium M which flows through the gas turbine 1 . The peripheral boundary 49 is in this case part of the peripheral turbine casing 15 . The rotor-side boundary 51 is in this case part of the turbine rotor 19 rotating when the gas turbine 1 is in the operating state.
[0040] As indicated diagrammatically in FIG. 1 and shown in detail in FIG. 2 , in this case the platform 33 of a guide blade 21 and the platform 43 of a moving blade 23 are formed by sheet metal parts fixed to the blade leaf 29 , 39 .
[0041] FIG. 2 shows, to represent a platform region 31 , 41 , a platform region 61 . The first turbine blade 63 and second turbine blade 65 , shown in FIG. 2 , in this case represents a first guide blade 21 of a first guide blade stage 7 and a second guide blade 21 , arranged directly axially downstream of this, of a second guide blade stage 9 . The first turbine blade 63 and the second turbine blade 65 also represent a first moving blade 23 , shown in FIG. 1 , of the first moving blade stage 11 and a second moving blade 23 , directly arranged axially downstream of this, of the second moving blade stage 13 . Preferably, however, the turbine blades 63 , 65 are guide blades.
[0042] The first turbine blade 63 has a blade leaf 69 depicted in truncated form. The second turbine blade 65 in this case has a blade leaf 67 depicted in truncated form. In the case of the first turbine blade 63 and of the second turbine blade 65 , the platform region 61 has formed in it, at the foot of the blade leaf 67 , 69 , a platform 71 which extends transversely with respect to the blade axis 73 , 75 . In this case, the platform 71 is formed, on the one hand, by a first resilient elastic sheet metal part 79 shown in the first blade 63 and, on the other hand, by a second sheet metal part 77 shown in the second blade 65 . The first resilient elastic sheet metal part 79 is fastened to a first abutment 83 on one side of the blade leaf 69 , this side being shown in the case of the first turbine blade 63 . The second resilient elastic sheet metal part 77 is fastened to a second abutment 81 on the other side of the blade leaf 67 , this side being shown in the case of the second turbine blade 65 . The fastening may take place, for example, by welding or soldering and is in this case leak tight. The first abutment 83 and the second abutment 81 are in each case designed in the form of a groove, into which in each case the first resilient sheet metal part 79 and the second sheet metal part 77 butts in each case with its edge ending at the blade leaf 69 or at the blade leaf 67 . Furthermore, the second resilient elastic sheet metal part 77 is held at a further abutment 85 of the second turbine blade 65 . In the present embodiment, the second sheet metal part 77 is attached to the abutment 85 . Alternatively or additionally, the second sheet metal part 77 could also engage behind the further abutment 85 . The latter case applies to the first resilient elastic sheet metal part 79 of the first turbine blade 63 , which sheet metal part is held jointly with the second sheet metal part 77 at the further abutment 85 of the second turbine blade 67 . For this purpose, the first resilient elastic sheet metal part 79 engages loosely behind the further abutment 85 . The further abutment 85 is designed in the form of a bearing support for holding the second sheet metal part 77 and the first resilient elastic sheet metal part 79 and thus forms, on its side facing the first resilient elastic sheet metal part 79 , a sealing surface which serves as an abutment for the first resilient elastic sheet metal part 79 .
[0043] A boundary 87 of the flow duct 5 is formed in the way outlined above between the first turbine blade 63 and the second turbine blade 65 by the first resilient elastic sheet metal part 79 of the first turbine blade 63 and by the second sheet metal part 77 of the second turbine blade 65 , the boundary 87 being continuous. Thus, the use of a thin-walled platform 71 which is not load-bearing for producing the boundary 87 in the form of a second sheet metal part 77 and of a first resilient elastic sheet metal part 79 makes it possible at the same time for the sheet metal parts 77 , 79 to act as a sealing element. A sealing element of this type is at the same time sufficiently flexible to allow relative movement of the adjacent first turbine blade 63 and second turbine blade 65 , and nevertheless has a sufficient sealing action. This avoids the need for a sealing element, such as would have been necessary for the sealing off of parting planes in the case of hitherto conventional platforms lying opposite one another. Potentially high-risk, structurally and thermally unfavorable reception structures of such a sealing element are consequently avoided.
[0044] In the embodiment shown here, the platform 71 largely manages on its rear side 89 without a supporting structure or a load-bearing platform wall arrangement. Instead, on the rear side 89 , a first cooling space 93 and a second cooling space 91 are formed, which make it possible to cool the platform 71 optimally in the region between the second turbine blade 65 and the first turbine blade 63 . Thus, a platform edge design which is otherwise normally complicated to configure can, in connection with the further abutment 85 , have a simpler configuration without any thermally high-risk region. To assist the cooling in the cooling spaces 91 , 93 , the carrying structure 95 , 97 of the turbine blades 65 , 63 which starts from the foot of the blade leaf 67 , 69 is continued with an optimized configuration toward the blade foot 35 , 47 in FIG. 1 .
[0045] The sealing action, provided particularly at the further abutment 85 , of the second sheet metal part 77 and of the first resilient elastic sheet metal part 79 arises, depending on the type of operation of the first turbine blade 63 and of the second turbine blade 65 , preferably in the form of a guide blade 21 shown in FIG. 1 or, if appropriate, also in the form of a moving blade 23 shown in FIG. 1 .
[0046] During the rotary operation of a turbine blade 65 , 63 in the form of a moving blade 23 on a turbine rotor 19 , to be precise, a centrifugal force acting from the foot of the blade leaf 67 , 69 in the direction 99 of the blade leaf 67 , 69 is generated as a result of rotation. A pressure drop, in the case of a guide blade 21 , also occurs in addition. It is also conceivable that the first resilient elastic sheet metal part 79 lies sealingly against the further abutment 85 by means of a prestress self-generated by the first resilient elastic sheet metal part 79 . The pressing force generated by the pressure drop can thereby be intensified.
[0047] During the operation of a turbine blade 65 , 63 in the form of a guide blade 21 , shown in FIG. 1 , on a peripheral turbine casing 15 , a pressure drop from the foot of the blade leaf 67 , 69 in the direction 99 of the blade leaf 67 , 69 is generated from the rear side 89 of a platform 71 by a cooling medium. The direction 99 of an abovementioned centrifugal force for a moving blade 23 also the direction 99 of the pressure drop for a guide blade 21 are identified in FIG. 2 by an arrow. Depending on the design of the turbine blade 67 , 69 as a moving blade 23 or as a guide blade 21 , therefore, the platform 71 in the form of the resilient elastic sheet metal parts 77 , 79 is pressed against the further abutment 85 by means of the centrifugal force or by means of the pressure drop. In this way, the sheet metal parts 77 , 79 of the platform 71 are fastened by centrifugal force or fastened by pressure and at the same time deploy their sealing action and separating action between the flow duct 5 , acted upon by hot gas, and the rear side 89 , acted upon by cooling medium, of the platform 71 .
[0048] In summary, in order to configure a boundary 87 of a flow duct 5 of a gas turbine 1 as simply as possible, in the case of a turbine blade 63 , 65 with a blade leaf 67 , 69 arranged along a blade axis 73 , 75 and with a platform region 61 which, arranged at the foot of the blade leaf
[0049] 67 , 69 , has a platform 71 extending transversely with respect to the blade axis 73 , 75 , it is proposed that the platform 71 be formed by a sheet metal part 77 , 79 fixed to the blade leaf 67 , 69 . This also applies to a gas turbine 1 with a flow duct 5 extending along an axis 3 of the gas turbine 1 and having an annular cross section for a working medium M, and with a second blade stage 9 , 13 arranged downstream of a first 7 , 11 along the axis 3 , a blade stage 7 , 9 , 11 , 13 having a number of annularly arranged turbine blades 63 , 65 extending radially into the duct 5 , according to the above concept. | The invention relates to a turbine blade comprising a vane that runs along a blade axis and a platform region, located at the root of the vane having a platform that extends transversally to the blade axis. The aim of the invention is to configure a delimitation of a flow channel of a gas turbine in the simplest possible manner. Therefore, the platform is configured by an elastic sheet metal part that rests on the vane. Said part leads to a gas turbine comprising a flow conduit that runs along an axis of the gas turbine, said conduit having an annular cross-section for a working medium and a second vane stage that is situated downstream of a first vane stage, which runs along the axis. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This patent application is a continuation of U.S. application Ser. No. 12/699,631, filed on Feb. 3, 2010, which is incorporated herein by reference.
BACKGROUND
[0002] Computer virtualization is a technique that involves encapsulating a physical computing machine platform into a virtual machine that is executed under the control of virtualization software on a hardware computing platform. Virtualization software enables multiple virtual machines to be run on a single hardware computing platform, and can manage the allocation of computing resources to each virtual machine.
[0003] A set of hardware computing platforms can be organized as a server cluster to provide computing resources for example, for a data center. In addition, supporting technology can move running virtual machines between servers (also referred to herein as “host systems”) in the cluster; an example of this supporting technology is sold as VMware VMotion™ by VMware, Inc. of Palo Alto, Calif. In addition, server cluster virtualization management software that incorporates cluster resource management technology can determine initial and ongoing locations of virtual machines on hardware computing platforms in the server cluster, and can manage the allocation of cluster computing resources. An example of this server cluster virtualization management software is sold as VMware Distributed Resource Scheduler™ by VMware, Inc. of Palo Alto, Calif. (hereinafter referred to as “DRS”). In addition, the server cluster virtualization management software can request that a server in the cluster power itself down, and can use mechanisms available in the marketplace to remotely power-on a server that is powered down. An example of this power management software is sold as the VMware Distributed Power Management feature within DRS by VMware, Inc. of Palo Alto, Calif. (hereinafter referred to as “DPM”).
[0004] Current implementations of DRS limit the cluster size to a certain number (N) of servers. As a consequence, resource management has to be carried out in groups of N servers or less. For data centers that operate considerably more than N servers and data centers that operate multiple groups of servers where each group is dedicated to a different customer or has a particular server configuration, DRS cannot ensure optimized resource management. Although resource usage within any single group of servers may be balanced using DRS, adding capacity to an overloaded group of servers cannot be easily done.
SUMMARY
[0005] One or more embodiments of the present invention provide a system and a method for automatically optimizing capacity between server clusters or groups that support a virtual machine computing environment. Such a system and method enable the balancing of resources across server clusters or groups and provides inter-cluster or inter-group resource sharing without compromising the isolation aspect of a server cluster or a server group.
[0006] According to this system and method, a software component monitors the capacity of server clusters or groups and automatically adds and removes host systems to and from server clusters or groups. The software component may be implemented at a server cluster management level to monitor and execute host system moves between server clusters and/or at a higher level in the resource management hierarchy. At the higher level, the software component is configured to monitor and execute host system moves between sets of server clusters being managed by different server cluster management agents.
[0007] A method of allocating physical computing resources in a virtual machine computing environment, according to an embodiment of the present invention, includes the steps of computing a usage metric of a multiple groups of server computers, determining a load imbalance between the groups, evacuating a host system in an under-utilized group, and allocating the evacuated host system to an over-utilized group. The host system move from the under-utilized group to the over-utilized group is carried out when the overall utilization is high enough. In situations where overall utilization is low, the host system move is not carried out although load imbalance has been determined.
[0008] A method of allocating physical computing resources in a virtual machine computing environment, according to another embodiment of the present invention, includes the steps of computing a usage metric of a group of server computers, determining a load imbalance for the group, and allocating an additional server computer to the group if the group is overloaded and deallocating one of the server computers of the group if the group is underloaded.
[0009] A hierarchical resource management system according to an embodiment of the present invention includes a plurality of first level resource managers, each configured to monitor a load imbalance across two or more clusters of server computers, and a second level resource manager configured to monitor a load imbalance between groups of server computers, where each group is monitored by one of the first level resource managers.
[0010] Other embodiments of the present invention include, without limitation, a computer-readable storage medium that includes instructions that enable a processing unit to implement one or more aspects of the disclosed methods as well as a system configured to implement one or more aspects of the disclosed methods.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic diagram of a hierarchical resource management system according to an embodiment of the present invention;
[0012] FIG. 2 illustrates the components of the hierarchical resource management system of FIG. 1 in additional detail;
[0013] FIG. 3 is a block diagram representing an example of a host system included in a cluster of servers shown in FIG. 1 ;
[0014] FIG. 4 illustrates the virtual cloud resource manager of FIG. 1 in additional detail;
[0015] FIGS. 5A and 5B conceptually illustrate the process of moving a host system from one server cluster to another server cluster;
[0016] FIG. 6 conceptually illustrates the process of evacuating a host system prior to moving the host system to a repository or another server cluster;
[0017] FIG. 7 is a flow diagram that depicts the steps carried out to balance resource usage between server clusters or server groups; and
[0018] FIG. 8 is a flow diagram that depicts the steps carried out to allocate or deallocate a host system.
DETAILED DESCRIPTION
[0019] FIG. 1 is a schematic diagram of a hierarchical resource management system 10 according to an embodiment of the present invention. Two levels of resource management are shown in FIG. 1 for simplicity. An embodiment of the present invention may be practiced with additional (higher) levels, e.g., a third level. A third level resource manager would operate similarly to a second level resource manager except that the third level resource manager would collect statistics data from and recommend host system moves to the second level resource managers (one of which is shown in FIG. 1 as cloud resource manager 40 ). At the first level, cluster managers 20 , 30 are managing resources for their respective server clusters. At the second level, virtual cloud resource manager 40 is managing resources for server clusters managed by cluster managers 20 , 30 . Resources being managed by system 10 are physical resources, namely server computers (or host systems) contained in server clusters 21 , 22 , 31 , 32 and server repositories 23 , 33 . Server clusters 21 , 22 and server repository 23 are under the control of cluster manager 20 and server clusters 31 , 32 and server repository 33 are under the control of cluster manager 30 . Cluster manager 20 and cluster manager 30 are server computers each programmed to manage its respective server clusters and server repository in the manner described herein.
[0020] The components of cluster manager 20 are detailed in FIG. 2 . Cluster manager 30 includes the same components except they are used to manage server clusters 31 , 32 and server repository 33 . The components of cluster manager 20 include a server cluster virtualization management software 201 which comprises a user interface 202 , DRS module 203 , and a DPM module 204 . An inter-cluster capacity manager 205 is implemented as an extension to server cluster virtualization management software 201 and communicates with server cluster virtualization management software 201 using Application Programming Interface (API) calls. Inter-cluster capacity manager 205 has three modules. The first module is a capacity monitor which collects at periodic intervals resource usage statistics. In one embodiment, resource usage statistics that are collected include the total idle capacity of each cluster managed by cluster manager 20 . In another embodiment, resource usage statistics that are collected include entitlement data for each running virtual machine (VM). Entitlement data for a VM at a point in time signifies the amount of resources the VM is entitled to at that point in time. The resource usage statistics may be supplied by a software component inside server cluster virtualization management software 201 that is separate from DRS module 203 or they may be supplied by DRS module 203 . The second module is a policy engine which stores information (policy) on how resources are to be allocated to each server cluster. The third module is a capacity balancer which receives inputs from the capacity monitor and the policy engine and makes decisions on host system moves accordingly. In one embodiment, the capacity balancer makes host system move decisions less frequently than entitlement data collection, because it may be desirable to analyze capacity trends prior to making a move decision. In either case, the frequency of data collection and the frequency of host system move decisions are configurable parameters. In another embodiment, as will be further described below, the capacity balancer makes host system move decisions by comparing a statistical measure of variance between normalized entitlements of server clusters.
[0021] In the embodiment described above, inter-cluster capacity manager 205 is shown as an extension of server cluster virtualization management software 201 . In alternative embodiments, inter-cluster capacity manager 205 may be a stand-alone software component that periodically polls each of the clusters for resource usage statistics or a software component inside server cluster virtualization management software 201 that periodically polls each of the clusters for resource usage statistics.
[0022] FIG. 2 further illustrates a representative structure for a server cluster. In the illustration, the components of server cluster 21 are shown but it should be understood that server clusters 22 , 31 , 32 have substantially the same structure, although the number of host systems can differ. Server cluster 21 includes a plurality of host systems 211 - 218 that are grouped or clustered together (physically or logically). Eight host systems 211 - 218 are shown here; however, in practice, server cluster 21 may include an arbitrary number of host systems.
[0023] A server repository 23 or 33 is a logical group of host systems that are made available for any of the server clusters to utilize. Some are powered off to preserve power consumption. Others are left powered on and booted for quick deployment.
[0024] FIG. 3 is a block diagram of a host system 300 in which one or more VMs are running and is representative of a host system in any of the server clusters. Host system 300 is the physical platform for one or more VMs (e.g., VM 321 , VM 322 , and VM 323 ) and has conventional hardware resources of a computing device, such as one or more CPUs 351 , system memory 352 , disk interface 353 , and network interface 354 . Examples of disk interface 353 are a host bus adapter and a network file system interface. An example of network interface 354 is a network adapter. The VMs run on top of a hypervisor (or virtual machine monitor) 340 , which is a software interface layer that enables sharing of the hardware resources of host system 300 . Persistent data storage is served by a storage device (not shown) connected via disk interface 353 .
[0025] FIG. 4 illustrates the virtual cloud resource manager of FIG. 1 in additional detail. The components of virtual cloud resource manager 40 include a software component referred to herein as a cloud capacity manager 405 . Cloud capacity manager 405 has three modules. The first module is a capacity monitor which collects resource usage statistics from cluster managers 20 , 30 . The second module is a policy engine which stores information (policy) on how resources are to be allocated to each set of clusters managed by cluster managers 20 , 30 . The third module is a capacity balancer which receives inputs from the capacity monitor and the policy engine, and makes decisions on host system moves accordingly.
[0026] A server repository 43 is a logical group of host systems that are made available by virtual cloud resource manager 40 for either cluster manager 20 , 30 to allocate. Some are powered off to preserve power consumption. Others are left powered on and booted for quick deployment.
[0027] FIG. 5A conceptually illustrates the process of moving a host system directly from one server group to another server group. The host system that is moved is initially contained in server cluster 22 . When cluster manager 20 determines through inter-cluster capacity manager 205 that server cluster 22 is underutilized and that server cluster 21 is overutilized, it deallocates a host system within server cluster 22 by evacuating the VMs running therein and making the host system available for server cluster 21 . In the example shown, host system 227 is selected for deallocation and is made available for allocation by server cluster 21 . The selection of host system 227 among all host systems running in server cluster 22 may be determined through any heuristic, e.g., host system with the smallest total entitlement. More complicated heuristics, e.g., the heuristic implemented in DPM 204 to select the host system to power down, may also be used.
[0028] FIG. 5B conceptually illustrates the process of moving a host system from one server group to another server group via a server repository 23 . The host system that is moved into server repository 23 is initially contained in server cluster 22 . When cluster manager 20 determines through inter-cluster capacity manager 205 that server cluster 22 is underutilized, it deallocates a host system within server cluster 22 by evacuating the VMs running therein and making the host system available for server cluster 21 . In the example shown, host system 227 is selected for deallocation and is made available for allocation by another server cluster by logically placing host system 227 in server repository 23 . The selection of host system 227 is made in the manner previously described.
[0029] Then, at a later time, when cluster manager 20 determines through inter-cluster capacity manager 205 that server cluster 21 is overutilized, it allocates a host system from server repository 23 (e.g., host system 227 ) to server cluster 21 . FIG. 5B also shows host systems 231 , 232 within server repository 23 . Cluster manager 20 may also allocate host system 231 or 232 to server cluster 21 , as needed. In addition, if server cluster 22 becomes overutilized, cluster manager 20 may also allocate host system 231 or 232 to server cluster 22 , as needed. For quicker deployment, any of host systems 231 , 232 , 227 in server repository 23 may be kept in a powered-on state. If power conservation is of higher priority, one or more of host systems in server repository 23 may be powered off. In certain instances, e.g., in situations where no cluster seems to be close to needing additional resources, host systems in server repository 23 may be powered off in a more aggressive manner. There also may be situations where a set number of host systems in server repository 23 , the set number being configurable, are kept powered on and the rest are powered off. In all of these different scenarios, the powered-off host systems need to be remotely powered on and booted for deployment.
[0030] FIG. 6 conceptually illustrates the process of evacuating a host system prior to moving the host system to a repository or to another server group. In this example, host system 227 has been selected for deallocation. Two VMs are shown running in host system 227 and thus they need to be moved to other host systems within server cluster 22 . As shown, one VM is moved to host system 224 and the other VM is moved to host system 226 . In one embodiment, the selection of destination host systems is made by DRS and the VMs are moved using VMware's VMotion™ technology. After evacuation, host system 227 is allocated to server cluster 21 in the embodiment of FIG. 5A or logically placed into server repository 23 for subsequent allocation in the embodiment of FIG. 5B .
[0031] FIG. 7 is a flow diagram that depicts the steps carried out to balance resource usage between server clusters or server groups. This method may be carried out by a cluster manager through its inter-cluster capacity manager or by a virtual cloud resource manager through its cloud capacity manager. In step 710 , resource usage statistics (in particular, entitlement data) are collected at regular intervals of time for each running VM. The entitlement data can be obtained using an API call into DRS. Entitlement data for a VM at a point in time signify the amount of resources the VM is entitled to at that point in time. Therefore, the total entitlement for all VMs running in a server cluster or in any server group signifies the amount of resources that are entitled to the VMs running in that server cluster or server group. In step 712 , a normalized entitlement for each server cluster or server group is computed by dividing the total entitlement by a number representing the total processing power and memory capacity of the server cluster or server group.
[0032] The equations for computing the normalized entitlement for a group of server clusters managed by a cluster manager (also referred to as Virtual Center or VC, for short), and at the cloud level are provided below. In the equations below, E VM is the entitlement value for a VM, E C DRS entitlement for a cluster C as calculated by DRS, Ë C DRS entitlement for a cluster C as adjusted for statistical smoothing, E VC VC is the total entitlement for a group of clusters managed by one cluster manager VC as calculated at the VC layer and Ë VC VC its statistically adjusted value. NE C is the normalized entitlement for a server cluster C. NE VC is the normalized entitlement for a group of server clusters managed by a cluster manager VC.
[0000] E C DRS =ΣE VM
[0000] (summation is done over all of the VMs in the cluster C)
[0000] Ë C DRS =mean (recent values of E C DRS )+two times the standard deviation from this mean
[0000] E VC VC =ΣË C DRS
[0000] (summation is done over all of the clusters C managed as a group by a VC)
[0000] Ë VC VC =mean (recent values of E VC VC )+two times the standard deviation from this mean
[0000] NE C =Ë C DRS /total resource capacity of server cluster C
[0000] NE VC =Ë VC VC /total resource capacity of a group of server clusters managed by VC
[0033] In the equations above, the entitlement value represents either processing power or memory capacity, and the normalized entitlement is calculated separately for each resource.
[0034] In step 714 , the normalized entitlements of two server clusters or server groups are compared to determine imbalance. In one example, the normalized entitlement of server cluster 21 is compared with the normalized entitlement of server cluster 22 to determine if there is any imbalance between these two server clusters. In another example, the normalized entitlement of a first server group containing host systems in server clusters 21 , 22 is compared with the normalized entitlement of a second server group containing host systems in server clusters 31 , 32 . If there is no imbalance, i.e., the difference between the two normalized entitlements is less than a predetermined threshold, the flow returns to step 710 . If there is an imbalance, i.e., the difference between the two normalized entitlements is greater than a predetermined threshold, step 716 is executed. In step 716 , a host system from the server cluster or server group with the lower normalized entitlement is evacuated and allocated to the server cluster or server group with the higher normalized entitlement. The movement of the host system can be carried out by making API calls into server cluster virtualization management software 201 to move the host system out of one server cluster and into another server cluster.
[0035] When determining imbalance, processing power imbalance may be evaluated, or memory capacity imbalance may be evaluated, or an overall imbalance may be evaluated. The overall imbalance is a weighted combination of the imbalance on each resource. The weight value for each is configurable and defaults to 0.25 for processing power and 0.75 for memory capacity.
[0036] In one embodiment, the decision block in step 714 is carried out with less frequency than steps 710 and 712 . Consequently, the decision on whether there is an imbalance is made by comparing the running averages of the normalized entitlements.
[0037] In one embodiment, the decision block in step 714 is carried out by comparing a statistical measure of variance between the normalized entitlements of server clusters or server groups. In one example, the variance (e.g., standard deviation) of normalized entitlements of server cluster 21 and server cluster 22 is calculated. If the variance (e.g., standard deviation) is above a user specified threshold, a host system is evacuated from the server cluster with the lower normalized entitlement and allocated to the server repository or a server cluster with the higher normalized entitlement. After such a move, the variance (e.g., standard deviation) is computed again and the process is repeated until no further moves are possible or the variance is below the threshold. In a similar manner, variance can be used to determine the imbalance between server groups.
[0038] A systematic search can be carried out to find a spare host system for one or more overloaded clusters. First, the server repository is examined and the spare host system is allocated from the server repository, if one is available. If not, the underloaded clusters and clusters in equilibrium are sorted in ascending order of normalized entitlement, and beginning from the top, look for host systems that have been powered down, and if none, select a host system from the most underloaded cluster.
[0039] In some embodiments of the present invention, the host system move from the under-utilized group to the over-utilized group may not be always carried out although the load imbalance is sufficiently high. In situations where overall utilization is low, e.g., the maximum normalized entitlement of the server clusters or groups is less than a predefined threshold, the host system move is not carried out although load imbalance is sufficiently high.
[0040] FIG. 8 is a flow diagram that depicts the steps carried out to allocate or deallocate a host system. This method may be carried out by a cluster manager through its inter-cluster capacity manager or by a virtual cloud resource manager through its cloud capacity manager. In this example, the host system is allocated from a server repository and configured with a default host profile, and, after deallocation, the host system is logically placed into a server repository. In step 810 , resource usage statistics (in particular, entitlement data) are collected at regular intervals of time for each running VM. The entitlement data can be obtained using an API call into DRS. Entitlement data for a VM at a point in time signify the amount of resources the VM is entitled to at that point in time. Therefore, the total entitlement for all VMs running in a server cluster or in any server group signifies the amount of resources that are entitled to the VMs running in that server cluster or server group. In step 812 , a normalized entitlement for the server cluster or server group is computed by dividing the total entitlement by a number representing the total processing power and memory capacity of the server cluster or server group. In step 814 , the normalized entitlement is compared to a predetermined upper threshold value. If the normalized entitlement is not greater than the upper threshold value, the normalized entitlement is compared to a predetermined lower threshold value. If the normalized entitlement is not less than the lower threshold value, the flow returns to step 810 .
[0041] On the other hand, if the normalized entitlement is greater than the upper threshold value, steps 816 and 818 are carried out, or if the normalized entitlement is less than the lower threshold value, steps 822 and 824 are carried out. In step 816 , a host system is allocated to the server cluster or server group from the server repository. Then, in step 818 , the host system is configured according to a default host profile of the server cluster to which it was added and DRS performs balancing of the workloads within that server cluster. In step 822 , a host system is selected from the server cluster or server group according to heuristics previously discussed and evacuated. Then, in step 824 , the evacuated host system is logically placed in the server repository. The movement of the host system can be carried out by making API calls into server cluster virtualization management software 201 to move the host system out of a server cluster or server repository and into a server cluster or server repository.
[0042] In one embodiment, the decision blocks in steps 814 and 820 are carried out with less frequency than steps 810 and 812 . Consequently, the decision on whether there is an imbalance is made by comparing the running averages of the normalized entitlements against the thresholds. In alternative embodiments, if a sudden rise in normalized entitlement is detected, the decision block in step 814 may be executed earlier than its scheduled time so that the sudden rise in processing and/or memory demands can be met in a timely manner.
[0043] In addition, various policies for resource management may be specified. For example, a default low limit and a default high limit may be defined for all server clusters. For some server clusters, these limits may be overridden with custom values. When the percentage of spare capacity is below the low limit, then a host system is added to the server cluster. When the percentage of spare capacity is above the high limit, then a host system is removed from the server cluster. If the low limit is 0% and the high limit is 100% for a server cluster, that server cluster will not be monitored.
[0044] The various embodiments described herein may employ various computer-implemented operations involving data stored in computer systems. For example, these operations may require physical manipulation of physical quantities usually, though not necessarily, these quantities may take the form of electrical or magnetic signals where they, or representations of them, are capable of being stored, transferred, combined, compared, or otherwise manipulated. Further, such manipulations are often referred to in terms, such as producing, identifying, determining, or comparing. Any operations described herein that form part of one or more embodiments of the invention may be useful machine operations. In addition, one or more embodiments of the invention also relate to a device or an apparatus for performing these operations. The apparatus may be specially constructed for specific required purposes, or it may be a general purpose computer selectively activated or configured by a computer program stored in the computer. In particular, various general purpose machines may be used with computer programs written in accordance with the teachings herein, or it may be more convenient to construct a more specialized apparatus to perform the required operations.
[0045] The various embodiments described herein may be practiced with other computer system configurations including hand-held devices, microprocessor systems, microprocessor-based or programmable consumer electronics, minicomputers, mainframe computers, and the like.
[0046] One or more embodiments of the present invention may be implemented as one or more computer programs or as one or more computer program modules embodied in one or more computer readable media. The term computer readable medium refers to any data storage device that can store data which can thereafter be input to a computer system. Computer readable media may be based on any existing or subsequently developed technology for embodying computer programs in a manner that enables them to be read by a computer. Examples of a computer readable medium include a hard drive, network attached storage (NAS), read-only memory, random-access memory (e.g., a flash memory device), a CD (Compact Discs), such as CD-ROM, a CD-R, or a CD-RW, a DVD (Digital Versatile Disc), a magnetic tape, and other optical and non-optical data storage devices. The computer readable medium can also be distributed over a network coupled computer system so that the computer readable code is stored and executed in a distributed fashion.
[0047] Although one or more embodiments of the present invention have been described in some detail for clarity of understanding, it will be apparent that certain changes and modifications may be made within the scope of the claims. Accordingly, the described embodiments are to be considered as illustrative and not restrictive, and the scope of the claims is not to be limited to details given herein, but may be modified within the scope and equivalents of the claims. In the claims, elements and/or steps do not imply any particular order of operation, unless explicitly stated in the claims.
[0048] In addition, while described virtualization methods have generally assumed that virtual machines present interfaces consistent with a particular hardware system, persons of ordinary skill in the art will recognize that the methods described may be used in conjunction with virtualizations that do not correspond directly to any particular hardware system. Virtualization systems in accordance with the various embodiments, implemented as hosted embodiments, non-hosted embodiments, or as embodiments that tend to blur distinctions between the two, are all envisioned. Furthermore, various virtualization operations may be wholly or partially implemented in hardware. For example, a hardware implementation may employ a look-up table for modification of storage access requests to secure non-disk data.
[0049] Many variations, modifications, additions, and improvements are possible, regardless the degree of virtualization. The virtualization software can therefore include components of a host, console, or guest operating system that performs virtualization functions. Plural instances may be provided for components, operations or structures described herein as a single instance. Finally, boundaries between various components, operations and data stores are somewhat arbitrary, and particular operations are illustrated in the context of specific illustrative configurations. Other allocations of functionality are envisioned and may fall within the scope of the invention(s). In general, structures and functionality presented as separate components in exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the appended claims(s). | A resource management system for a virtual machine computing environment includes a software component that optimizes capacity between server clusters or groups by monitoring the capacity of server clusters or groups and automatically adding and removing host systems to and from server clusters or groups. The software component may be implemented at a server cluster management level to monitor and execute host system moves between server clusters and/or at a higher level in the resource management hierarchy. At the higher level, the software component is configured to monitor and execute host system moves between sets of server clusters being managed by different server cluster management agents. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to printing apparatus such as electrophotographic copying machines and electrophotographic printers, and more particularly to an electrophotographic recording apparatus having an exposing unit on a cover thereof.
[0003] 2. Description of the Related Art
[0004] With conventional printing apparatus such as electrophotographic copying machines and electrophotographic printers, the operator opens a lid to replace an image-forming unit and/or a toner cartridge or to remove jammed paper. The lid is usually of simple construction in which the lid is opened and closed substantially in a vertical direction.
[0005] Among the electrophotographic printers on the market is one in which, for example, an LED head as an exposing unit used for electrophotography is mounted on a lid. Such a printer includes four LED heads for forming yellow, magenta, cyan, and black images on corresponding image forming units.
[0006] However, such a conventional electrophotographic recording apparatus having LED heads suffers from the problem that when the operator opens a lid to replace an image-forming unit and/or a toner cartridge or to remove jammed paper, the LED heads that project downward from the lid interfere with the operator's hands. In order that the LED heads do not interfere with the operator's hands, the lid should be designed to open wider.
SUMMARY OF THE INVENTION
[0007] The present invention was made in view of the aforementioned drawbacks of the conventional apparatus.
[0008] An object of the invention is to provide an electrophotographic recording apparatus in which when the user replaces a toner cartridge and/or image forming unit or removes jammed paper, an exposing unit does not obstruct the operations.
[0009] An electrophotographic recording apparatus according to the invention has a lid movable to open and close relative to a body of the apparatus, the lid having an exposing unit mounted thereto. The recording apparatus comprises a collapsible mechanism and a gear mechanism. The collapsible mechanism can be selectively deformed into a collapsed position and into an expanded position. The gear mechanism drives the collapsible mechanism to deform selectively into the collapsed position and the expanded position. When the lid is opened, the collapsible mechanism causes the exposing unit to move to a retracted position. When the lid is closed, the collapsible mechanism causes the exposing unit to move to an extended position. When the lid is opened and closed, said gear mechanism operates operatively with the lid to cause the collapsible mechanism to be selectively deformed into the collapsed position and into the expanded position.
[0010] The exposing unit extends longitudinally and has a first longitudinal end and a second longitudinal end. When the lid is opened, one of the first and second longitudinal ends is moved to the retracted position.
[0011] The exposing unit is mounted to the collapsible mechanism through a biasing member. When the lid is closed, the collapsible mechanism is deformed into the expanded position so that the exposing unit is placed in position with respect to an image-forming unit and the biasing member urges the exposing unit against the image-forming unit.
[0012] The gear mechanism may include a torque limiter.
[0013] The exposing unit extends substantially parallel to an axis about which the lid pivots to open and close.
[0014] The exposing unit extends in a direction substantially perpendicular to an axis about which the lid pivots to open and close.
[0015] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limiting the present invention, and wherein:
[0017] [0017]FIG. 1 is a perspective view of a pertinent portion of an electrophotographic printer according to a first embodiment of the invention;
[0018] [0018]FIG. 2 is a side view of the LED assemblies and associated structural elements of the image recording apparatus;
[0019] [0019]FIG. 3 is a fragmentary front view of a pertinent portion of the first embodiment when the lid is opened;
[0020] [0020]FIG. 4 is a fragmentary side view of a pertinent portion of the first embodiment when a lid is completely closed;
[0021] FIGS. 5 - 8 illustrate the opening operation of the lid according to the first embodiment;
[0022] FIGS. 9 - 12 illustrate the closing operation of the first embodiment;
[0023] [0023]FIG. 13 is a perspective view of a pertinent portion of an electrophotographic printer according to a second embodiment; FIG. 14 is a fragmentary plan view illustrating the second embodiment;
[0024] FIGS. 15 - 17 illustrate the operation of the second embodiment;
[0025] [0025]FIG. 18 is a perspective view of a pertinent portion of an electrophotographic printer according to a third embodiment;
[0026] [0026]FIG. 19 is a fragmentary view of a pertinent portion of the third embodiment;
[0027] [0027]FIG. 20 is a side view of a pertinent portion of the third embodiment; and
[0028] [0028]FIG. 21 is the bottom view of the LED head 6 .
DETAILED DESCRIPTION OF THE INVENTION
[0029] Embodiments of the invention will be described in detail with reference to the accompanying drawings.
[0030] First embodiment
[0031] {Construction}
[0032] Embodiments of the invention will be described with respect to an electrophotographic printer as an electrophotographic recording apparatus. The electrophotographic printer incorporates an LED head as an exposing unit.
[0033] [0033]FIG. 1 is a perspective view of a pertinent portion of an electrophotographic printer according to a first embodiment of the invention.
[0034] Referring to FIG. 1, an electrophotographic printer 1 has a body 2 . The lid 3 is pivotally assembled to the main frame of the body 2 . The lid 3 has a pair of supporting projections 4 on the left and right ends thereof. A sector gear 3 a is formed on the left side of the lid 3 in one-piece construction with the lid 3 such that the sector gear 3 a is rotatable about an axis passing through the centers of the pair of supporting projections 4 . The lid 3 has a pair of support shafts 11 a and 11 b that are rotatably supported by bearings, not shown, and extend parallel to each other.
[0035] There are four LED assemblies 5 assembled to an inner surface of the lid 3 , the LED assemblies 5 being aligned at equal intervals. FIG. 1 shows only one of the LED assemblies 5 in the detail and three others in phantom lines. The four LED head assemblies 5 are provided because the electrophotographic printer according to the first embodiment is a color printer. If an electrophotographic printer is a monochrome printer, only one LED head assembly is required. Each of the LED head assemblies 5 includes an LED head 6 , a pair of compression springs 7 , a sub plate 8 , a pair of base inks 9 a and 9 b , and a pair of interconnecting links 10 a and 10 b.
[0036] The base links 9 a and 9 b and the interconnecting links 10 a and 10 b have a U-shaped cross section. The base links 9 a and 9 b have top end portions firmly connected to front end portions of the support shafts 11 a and 11 b , respectively. The lower end portions of the base links 9 a and 9 b partially enter the upper end portions of the interconnecting links 10 a and 10 b such that the base links are pivotally coupled to corresponding the interconnecting links by means of coupling pins 12 a and 12 b.
[0037] [0037]FIG. 2 is a side view of the LED assemblies 5 and associated structural elements of the printer. Referring to FIG. 2, the four LED head assemblies 5 are mounted to the lid 3 such that they face corresponding image-forming units 21 accurately when the lid 3 is completely closed.
[0038] [0038]FIG. 3 is a fragmentary front view of a pertinent portion of the first embodiment when the lid 3 is opened.
[0039] Referring to FIG. 3, the interconnecting link 10 a is pivotal clockwise about a coupling pin 13 a but is prevented from pivoting counterclockwise due to the fact that when the interconnecting link 10 a pivots counterclockwise, the upper portion of the interconnecting link 10 a abuts the lower end portion of the base link 9 a. Specifically, the interconnecting link 10 a is prevented from further pivoting counterclockwise when the interconnecting link 10 a pivots such that the coupling pin 12 a is outside of a line La connecting the support shaft 11 a and the coupling pin 13 a.
[0040] The relation between the lower end portion of the base link 9 b and the interconnecting link 10 b is similar to that between the lower end portion of the base link 9 a and the interconnecting link 10 a . In other words, the interconnecting link 10 b is pivotal clockwise about a coupling pin 13 b but is prevented from pivoting counterclockwise due to the fact that the upper portion of the interconnecting link 10 b abuts the lower end portion of the base link 9 b . Specifically, the interconnecting link 10 b is prevented from further pivoting counterclockwise when the interconnecting link 10 b pivots such that the coupling pin 12 b is outside of a line Lb connecting the support shaft 11 b and the coupling pin 13 b.
[0041] The lower end portions of the interconnecting links 10 a and 10 b are coupled to upward projections 8 a and 8 b , formed on the left and right end portions of the support plate 8 , by means of the coupling pins 13 a and 13 b , respectively. Each of the compression springs 7 has one end thereof connected to the underside of the support plate 8 and the other end thereof connected to the LED head 6 . The LED head 6 is suspended from the supporting plate 8 by means of the compression springs 7 . The LED head 6 has engagement holes 6 a and 6 b (FIG. 3) formed in longitudinal end portions thereof.
[0042] Disposed below the respective LED heads 6 are corresponding image-forming units 21 . Each of the image-forming units 21 has pilot pins 21 a and 21 b that correspond to the engagement holes 6 a and 6 b of the LED head 6 , respectively. When the pilot pins 21 a and 21 b enter the engagement holes 6 a and 6 b , respectively, the LED heads 6 are placed in position.
[0043] [0043]FIG. 4 is a fragmentary side view of a pertinent portion of the first embodiment when the lid 3 is completely closed.
[0044] Referring to FIGS. 1 and 4, the support shafts 11 a and 11 b have worm wheels 14 a and 14 b secured to the rear end portions of the support shafts 11 a and 11 b . The shaft 16 is in line with the pair of supporting projections 4 formed in the lid 3 but not coupled to the supporting projections 4 . The shaft 16 is rotatably supported by bearings, not shown, provided on the lid 3 . The shaft 16 also has worm gears 17 a and 17 b and an idle gear 18 , which are secured to the shaft 16 . The worm gears 17 a and 17 b are in mesh with worm wheels 14 a and 14 b , respectively, and the idle gear 18 is disposed close to the sector gear 3 a.
[0045] Referring to FIG. 1, a main gear 19 is rotatably supported on a rear end of the body 2 near the sector gear 3 a . The main gear 19 is in mesh with a sub gear 20 rotatably supported on the body 2 . When the main gear 19 moves into meshing engagement with the sector gear 3 a , the pivotal motion of the lid 3 is transmitted from the main gear 19 to the idle gear 18 . The pivotal motion is further transmitted from the idle gear 18 to the support shaft 11 a and 11 b through the worm gears 17 a and 17 b and worm wheels 14 a and 14 b . The sector gear 3 a is shaped such that the sector gear 3 a moves into meshing engagement with the main gear 19 after the lid 3 has pivoted to a certain angle from a position where the lid 3 is completely closed to a position where the lid is partially opened.
[0046] {Operation of the first embodiment}
[0047] {Opening operation}
[0048] FIGS. 5 - 8 illustrate the opening operation of the lid according to the first embodiment.
[0049] The opening operation of the lid 3 will now be described with reference to FIGS. 5 - 8 . When the lid 3 is completely closed as shown in FIG. 3, the upper end portions of the interconnecting links 10 a and 10 b abut the lower end portions of the base links 9 a and 9 b , respectively, preventing the interconnecting links 10 a and 10 b from further pivoting. Thus, the LED head assembly 5 is firmly positioned with the aid of the urging forces of the compression springs 7 .
[0050] After the operator unlocks the lid 3 by operating a locking mechanism, not shown, the operator raises the lid 3 such that the lid 3 pivots from the closed position shown in FIG. 4 in a direction shown by arrow A of FIG. 5. At this moment, the sector gear 3 a is not in mesh with the main gear 19 yet. The pin holes 6 a and 6 b of the LED head 6 will move out of engagement with the pilot pins 21 a and 21 b of the image-forming unit 21 before the sector gear 3 a moves into meshing engagement with the main gear 19 . When the lid 3 is further opened, the sector gear 3 a moves into meshing engagement with the main gear 19 , so that the main gear 19 rotates clockwise as shown by arrow B in FIG. 5. Then, the rotary motion of the main gear 19 is transmitted to the idle gear 18 . The idle gear 18 then transmits the rotary motion to the support shafts 11 a and 11 b through the warm gears 17 a and 17 b , respectively. As a result, the support shaft 11 a rotates in a direction shown by arrow C (counterclockwise) in FIG. 6, and the support shaft 11 b rotates in a direction shown by arrow D (clockwise).
[0051] As the support shaft 11 a rotates, the base link 9 a and interconnecting link 10 a collapse such that one is folded over the other as shown in FIG. 6. Likewise, as the support shaft 11 b rotates, the base link 9 b and interconnecting link 10 b collapse such that one is folded over the other. As the base links 9 a and 9 b and the interconnecting links 10 a and 10 b collapse, the LED head assembly 5 is deformed from an expanded position toward a collapsed position.
[0052] When the lid 3 has been fully opened as shown in FIG. 7, the LED assembly 5 has completely collapsed as shown in FIG. 8. The lid 3 is at its open position where the lid 3 is at an angle greater than 90 degrees with respect to its closed position and is held at the open position.
[0053] Then, with the lid 3 opened, the operator replaces the toner cartridge and/or the image-forming unit or removes jammed paper. Since the LED assemblies are at their collapsed positions, the LED assemblies 5 do not interfere with the operator's hands, facilitating replacement of the toner cartridge and/or the image-forming unit or removal of the jammed paper.
[0054] {Closing operation}
[0055] FIGS. 9 - 12 illustrate the closing operation of the first embodiment.
[0056] When the lid 3 is fully opened as shown in FIG. 7, the sector gear 3 a is in meshing engagement with the main gear 19 . As the operator closes the lid 3 in a direction shown by arrow F as shown FIG. 9, the sequence of the aforementioned opening operation is reversed. In other words, referring to FIG. 9, the main gear 19 rotates counterclockwise shown by arrow E, and the rotary motion of the main gear 19 is transmitted to the idle gear 18 through the sub gear 20 . The rotary motion of the idle gear is then transmitted to the support shafts 11 a and 11 b through the worm gear gears 17 a and 17 b and worm wheels 14 a and 14 b . Then, as shown in FIG. 10, the support shaft 11 a rotates in a direction shown by arrow G (clockwise) while the support shaft 11 b rotates in a direction shown by arrow H (counterclockwise).
[0057] As shown in FIG. 11, the clockwise rotation of the support shaft 11 a causes the base link 9 a and interconnecting link 10 a to gradually open from their collapsed state. The counterclockwise rotation of the support shaft 11 b causes the base link 9 b and the interconnecting link 10 b to gradually open from their collapsed state. The coupling pins 12 a and 12 b will have moved outside of the lines La and Lb, respectively, as shown in FIG. 12, before the sector gear 3 a moves out of meshing engagement with the main upper gear 19 as shown in FIG. 11. Thus, in FIG. 12, the upper end corners 10 a ′ and 10 b ′ of the U-shaped interconnecting links 10 a and 10 b abut the common parts 9 a ′ and 9 b ′ of the U-shaped base links 9 a and 9 b , thereby preventing the interconnecting links 10 a and 10 b from further pivoting. At this moment, neither a compressive force nor a tensile force is exerted to the compression coil spring 7 .
[0058] As the lid 3 is further closed, the sector gear 3 a moves out of engagement with the main gear 19 but the worm gear 17 a and 17 b cause the interconnecting links 10 a and 10 b and the base links 9 a and 9 b to stay at their positions. Then, the pilot pins 21 a and 21 b enter the engagement holes 6 a and 6 b formed in the LED head 6 , thereby placing the LED head 6 in position above the image-forming unit 21 .
[0059] When the LED head 6 is positioned above the image-forming unit 21 , the compression spring 7 starts to be compressed so that the spring 7 urges the interconnecting links 10 a and 10 b and the base links 9 a and 9 b . However, the worm gears 17 a and 17 b prevent the base links 9 a and 9 b from pivoting, and the upper end corners 10 a ′ and 10 b ′ of the interconnecting links 10 a and 10 b abut the common parts 9 a and 9 b of the base links 9 a and 9 b . Therefore, the interconnecting links 10 a and 10 b and the base links 9 a and 9 b are not collapsed but remain positioned over the image-forming unit 21 as shown in FIG. 12. Subsequently, the lid 3 is pivoted further in the closing direction so that the compression spring 7 exerts a large biasing force on the LED head 6 . After the lid 3 has been completely closed, the operator locks the lid 3 to the body 2 by operating a fastening means, not shown.
[0060] The first embodiment is advantageous in that the LED head assemblies 5 do not obstruct the operator's hands and it is only necessary for the operator o open the lid 3 through a small pivotal angle because the LED head assemblies 5 collapses into a small size.
[0061] Second Embodiment
[0062] {Construction}
[0063] [0063]FIG. 13 is a perspective view of a pertinent portion of an electrophotographic printer according to a second embodiment.
[0064] [0064]FIG. 14 is a fragmentary plan view illustrating the second embodiment.
[0065] Referring to FIG. 13, the rear end portions of the support shafts 11 a and 11 b are firmly supported by means of torque limiters 30 a and 30 b . The torque limiters 30 a and 30 b each include an inner ring member and an outer ring member. When a torque smaller than a predetermined value acts on the inner and outer ring members, the inner and outer ring members rotate together. When a torque larger than the predetermined value acts on the inner and outer ring members, one ring member rotates relative to the other with a certain torque acting on them.
[0066] Referring to FIG. 14, the stoppers 31 a and 31 b are provided on the inner surface of the lid 3 and restrict the rotation of the base links 9 a and 9 b . The rest of the construction is the same as the first embodiment.
[0067] {Operation of the second embodiment}
[0068] {Opening operation}
[0069] FIGS. 15 - 17 illustrate the operation of the second embodiment.
[0070] The opening operation of the lid of the second embodiment will now be described with reference to FIGS. 15 - 17 .
[0071] Just as in the first embodiment, when the lid 3 has been completely closed, the upper end corners 10 a ′ and 10 b ′ of the interconnecting links 10 a and 10 b abut the upper common parts 9 a ′ and 9 b ′ of the base links 9 a and 9 b . Therefore, the interconnecting links 10 a and 10 b are prevented from pivoting and the compression springs 7 urge the LED head 6 against the image-forming unit 21 and the sector gear 3 a has not been in meshing engagement with the main gear 19 yet.
[0072] Referring to FIG. 15, when the operator opens the lid 3 , the lid 3 pivots in a direction shown by arrow I but the sector gear 3 a is not in meshing engagement with the main gear 19 until the lid 3 opens to an angle greater than a predetermined value. Before the sector gear 3 a moves into meshing engagement with the main gear 19 , the LED head 6 will have moved out of engagement with the pilot pins 21 a and 21 b of the image-forming unit 21 . When the lid 3 is further opened, the sector gear 3 a moves into meshing engagement with the main gear 19 , so that the main gear 19 starts to rotate clockwise. The rotation of the main gear 19 is transmitted to the idle gear 18 through the sub gear 20 , and then to the support shafts 11 a and 11 b through the worm gears 17 a and 17 b and worm wheels 14 a an 14 b . As a result, as described in the first embodiment, the base links 9 a and 9 b and the interconnecting links 10 a and 10 b collapse into a folded position, so that the LED assemblies 5 are collapsed from their expanded positions to their collapsed positions.
[0073] When the lid 3 is still further opened, the upper end corners 9 a ′ and 9 b ′ of the base links 9 a and 9 b abut the stoppers 31 a and 31 b as shown in FIG. 17, and the base links and interconnecting links are not further collapses.
[0074] As shown in FIG. 16, if the operator attempts to further open the lid 3 in the direction shown by arrow J, the lid 3 can be opened with the support shafts 11 a and 11 b not rotated. This is because the torque limiters 30 a and 30 b becomes operative, so that the pivotal motion of the lid 3 is transmitted to the worm gears 17 a and 17 b of the relay shaft 16 and not from the worm gears 17 a and 17 b to the worm wheels 14 a and 14 b.
[0075] When the lid 3 has been completely opened, the operator replaces the cartridge and/or the image-forming unit or removes jammed paper. At this moment, just like the first embodiment, the LED head assemblies 5 are at their collapsed positions, facilitating replacement of the cartridge and/or image-forming unit or removal of the jammed paper.
[0076] {Closing operation}
[0077] The closing operation of the lid 3 will now be described with reference to FIGS. 15 and 16.
[0078] When the lid 3 is fully opened, the sector gear 3 a is in mesh with the main gear 19 . When the operator starts to close the lid 3 from this position, the sequence of the aforementioned opening operation is reversed so that the base links 9 a and 9 b and the interconnecting links 10 a and 10 b gradually open from their collapsed position.
[0079] Before the lid 3 is closed to the position shown in FIG. 15 where the sector gear 3 a moves out of engagement with the main gear 19 , the coupling pins 12 a and 12 b will have become outside of the lines La and Lb (FIG. 12), respectively. The upper end corners 9 a ″ and 9 b ″ of the base links 9 a and 9 b abut the stoppers 31 a and 31 b to prevent the basing links 9 a and 9 b from pivoting.
[0080] When the lid 3 has been fully opened, the interconnecting links 10 a and 10 b and the base links 9 a and 9 b are in their expanded positions as shown in FIG. 14 and the torque limiters 30 a and 30 b remain operative. In this situation, the torque limiters 30 a and 30 b operate so that the rotation of the lid 3 is not transmitted to the support shafts 11 a and 11 b . In other words, the lid 3 can pivot further in the closing direction with the support shafts 11 a and 11 b not rotating. If the gear ratio is designed such that the support shafts 11 a and 11 b rotate a larger number of times for the same amount of pivotal motion of the lid 3 , then the interconnecting links 10 a and 10 b and the base links 9 a and 9 b operate as follows. When the lid 3 is closed from its fully opened position, the interconnecting links 10 a and 10 b and the base links 9 a and 9 b move into their fully expanded positions when the lid 3 is still wide open. When the lid 3 is opened from its fully closed position, the interconnecting links 10 a and 10 b and the base links 9 a and 9 b move into their fully collapsed positions when the lid 3 is not wide open yet.
[0081] Conversely, if the gear ratio is designed such that the support shafts 11 a and 11 b rotate a smaller number of times for the same amount of pivotal motion of the lid 3 , then the interconnecting links 10 a and 10 b and the base links 9 a and 9 b are in their expanded positions when the lid 3 is still wide open.
[0082] When the lid 3 is further pivoted in the closing direction, the sector gear 3 a moves out of engagement with the main gear 19 . Then, the worm gears 17 a and 17 b hold the interconnecting links 17 a and 17 b and the base links 9 a and 9 b at their positions, and the pilot pins 21 a and 21 b of the image-forming unit 21 move into engagement with the engagement holes 6 a and 6 b formed in the LED head 6 . Thus, the LED head 6 is placed in position with respect to the image-forming unit 21 .
[0083] Since the LED head 6 is positioned on the image-forming unit 21 , the compression springs 7 are compressed such that the urging forces of the compression springs 7 act on the interconnecting links 10 a and 10 b and the base links 9 a and 9 b . However, the upper end corners 9 a ″ and 9 b ″ of the base links 9 a and 9 b abut the stoppers 31 a and 31 b . In addition, the upper end corners 10 a ′ and 10 b ′ of the interconnecting links 10 a and 10 b abut the common parts 9 a ′ and 9 b ′ of the base links 9 a and 9 b having a U-shaped cross section. Therefore, the overall structure of the base links 9 a and 9 b the interconnecting links 10 a and 10 b is prevented from buckling, placing the LED head 6 positioned above the image-forming unit 21 . Since the interconnecting links 10 a and 10 b and base links 9 a and 9 b do not collapse, the compression springs 7 exert large urging forces on the LED head 6 so that the LED head 6 is positioned relative to the image-forming unit 21 . When the lid 3 has been completely closed, the operator locks the lid 3 to the body by means of a fastening means, not shown.
[0084] As described above, the second embodiment provides the same advantages as the first embodiment. In addition, the use of the torque limiters 30 a and 30 b allows the lid 3 to be opened wider or to a desired position. The second embodiment has been described with respect to a case where when the lid 3 has been completely closed, the sector gear 3 a is not in mesh with the main gear 19 . However, the mechanism may also be designed such that the sector gear 3 a is in mesh with the main gear at all times.
[0085] Third embodiment
[0086] {Construction}
[0087] [0087]FIG. 18 is a perspective view of a pertinent portion of an electrophotographic printer according to a third embodiment.
[0088] [0088]FIG. 19 is a fragmentary view of a pertinent portion of the third embodiment.
[0089] [0089]FIG. 20 is a side view of a pertinent portion of the third embodiment.
[0090] The third embodiment is characterized in that a lid has supporting projections that extend perpendicular to the longitudinal direction of the LED head.
[0091] Referring to FIGS. 18 - 20 , an electrophotographic printer has a lid 53 pivotally mounted to a frame 52 of the printer such that the lid 53 can be opened and closed. The lid 53 has a pair of supporting projections 54 on the left and right sides of the printer so that the lid 53 is rotatably mounted to the frame 52 by means of the supporting projections 54 . A sector gear 53 a is formed in one-piece construction with the lid 53 , the sector gear 53 a rotating about an axis passing through the centers of the supporting projections 54 . There are provided four LED assemblies 5 on the inner side of the lid 53 , the LED assemblies 5 being positioned such that each of the LED assemblies 5 extends in a direction perpendicular to the axis passing through the supporting projections 54 .
[0092] Each of the LED assemblies 5 includes the LED head 6 , a pair of compression coil springs 7 , a support plate 8 , a base link 9 , an interconnecting link 10 , and a long link 55 . The base link 9 , interconnecting link 10 , and long link 55 have a U-shaped cross-section. The base link 9 and interconnecting link 10 are disposed on a rear side of the lid 3 (i.e., near rotational axis X). The long link 55 is disposed on a front side of the lid 3 (i.e., the side remote from the rotational axis X). The base link 9 , interconnecting link 10 , and the long link 55 cooperate to support the LED head 6 .
[0093] A support shaft 11 extends parallel to the pivotal axis of the lid 53 and is rotatably mounted on the rear side of the lid 53 by means of bearings, not shown. The upper end portion of the base link 9 is fixed to the support shaft 11 so that the rotation of the support shaft 11 causes the base link 9 to pivot. The lower end portion of the base link 9 enters the upper end portion of the interconnection link 10 such that the base link 9 and the interconnecting link 10 are pivotally coupled by a coupling pin 12 to each other.
[0094] As shown in FIG. 19, the interconnecting link 10 can sufficiently pivot counterclockwise with respect to the base link 9 but is prevented from rotating clockwise because the upper end corner 10 ′ of the interconnecting link 10 abuts the common parts 9 ′ of the base link 9 . The interconnecting link 10 stops pivoting at a position where the coupling pin 12 becomes outside of a line L connecting the support shaft 11 and the coupling pin 13 b . The lower end portion of the interconnecting link 10 and an upward projection 8 b of the support plate 8 are coupled together by means of the coupling pin 13 b such that they are pivotal to each other.
[0095] The long link 55 has an upper end portion rotatably supported on a coupling pin 56 formed on the inner side of the lid 53 , and a lower end portion coupled to the projection 8 b of the support plate 8 by means of the coupling pin 13 a . The lid 53 has opposing stoppers 53 c and 53 d formed on the inner surface thereof with the upper end portion of the long link 55 between the stoppers 53 c and 53 d . The stoppers 53 c and 53 d restrict the motion of the long link 55 such that the long link 55 can pivot only in a limited range. The lid 53 also has a stopper 53 e formed on the inner surface thereof, the stopper 53 e being located at an upper left side of the base link 9 in FIG. 19.
[0096] [0096]FIG. 21 is the bottom view of the LED head 6 .
[0097] There are provided compression springs 7 under longitudinal ends of the support plate 8 . Each of the springs 7 has one end connected to the support plate 8 and the other end connected to the LED head 6 . In other words, the LED head 6 is suspended from the support plate 8 via the springs 7 . The LED head 6 has an engagement hole 56 a formed in one of the longitudinal ends thereof and a U-shaped cutout 56 b formed in the other.
[0098] Referring back to FIG. 19, there are provided image-forming units 21 under the respective LED head assemblies 5 . Each of the image-forming units 21 has pilot pins 21 a and 21 b corresponding to the engagement hole 56 a and the cutout 56 b formed in the corresponding LED head 6 , respectively. The pilot pins 21 a and 21 b enter the engagement hole 56 a and cutout 56 b , respectively, so that the LED head 6 is placed in position.
[0099] The support shaft 11 has a gear 57 fixedly mounted to an end portion of the support shaft 11 . There is provided a relay gear 58 that rotates about an axis passing through the pair of supporting projections 54 and is in mesh with the gear 57 . The main gear 53 a is rotatably supported on a rear side of the lid 53 where the sector gear 53 a is formed. The main gear 19 is in mesh with the sector gear 53 a . A sub gear 60 is rotatably provided which is in mesh with both the main gear 59 and the relay gear 58 .
[0100] With the aforementioned gear mechanism, the pivotal motion of the lid 53 is transmitted through the sector gear 53 a from the main gear 59 through the sub gear 60 to the relay gear 58 . The rotation is further transmitted through the gear 57 to the support shaft 11 . As shown in FIG. 19, when the lid 53 has been completely closed, the sector gear 53 a and the main gear 59 are not in mesh with each other.
[0101] {Operation of the third embodiment}
[0102] The operation of the third embodiment will now be described.
[0103] When the lid 3 has been completely closed, the upper end corner 10 ′ of the interconnecting link 10 abuts a bottom part of the U-shaped base link 9 so that the interconnecting link 10 is prevented from further pivoting and the LED head assemblies 5 are fixedly placed in position. When the lid 53 has been completely closed, the sector gear 53 a and the main gear 59 are not in mesh with each other.
[0104] {Opening operation}
[0105] When the user unlocks a fastening means, not shown, and opens the lid 53 from the fully closed position (FIG. 19), the lid 53 pivots. The sector gear 53 a is not in meshing engagement with the main gear 59 until the lid 53 has pivoted beyond a predetermined angle. If the lid 53 is further opened in a direction shown by arrow K in FIG. 20 beyond the predetermined angle, then the sector gear 53 a moves into meshing engagement with the main gear 59 , so that the main gear 59 rotates counterclockwise. The rotation of the main gear 59 is transmitted through the sub gear 60 to the relay gear 58 and further to the support shaft 11 through the gear 57 . Just like the first embodiment, the rotation of the support shaft 11 causes the base links 9 and interconnecting links 10 to collapse so that each of the LED head assemblies 5 moves from its extended position to its collapsed position.
[0106] As shown in FIG. 20, as the base link 9 and interconnecting link 10 are folded one over the other, the long link 55 pivots counterclockwise slightly about the coupling pin 56 until the upper end of the long link 55 abuts the limiter 53 c.
[0107] As the lid 53 is further opened, the upper portion 9 ′ of the base link 9 abuts the stopper 53 e as shown in FIG. 20, the limiter 53 e preventing the base link 9 and the interconnecting link 10 from further collapsing. When the LED head assembly 5 takes the position shown in FIG. 20, the collapse of one end of the LED head assembly 5 is completed. When the lid 53 is fully opened, the lid 53 can be at an angle that is greater than 90 degrees just as in the first embodiment.
[0108] After the lid 53 has been opened fully, the operator replaces the toner cartridge and/or image-forming unit or removes jammed paper. Because one end of the LED head assembly 5 has collapsed, the LED head assembly 5 does not interfere with the operator's hands.
[0109] {Closing operation}
[0110] The closing operation of the lid 53 will be described.
[0111] When the lid 53 is fully opened, the sector gear 53 a is still in mesh engagement with the main gear 59 . As the lid 53 is closed from where it is fully opened, the rotations of the associated parts of the mechanism are reversed with respect to the opening operation of the lid 53 . In other words, the base links 9 and the interconnecting links 10 will move from their collapsed positions toward their expanded positions. The coupling pin 12 will be outside of the line L (FIG. 19) that connects the support shaft 11 and the coupling pin 13 before the sector gear 53 a moves out of engagement with the main gear 59 . When the shaft 12 is outside of the line L, the upper end portion 9 ′ of the base link 9 abuts the stopper 53 e and the upper end corner 10 ′ of the interconnecting link 10 abuts the common part 9 ′ of the base link 9 . Thus, the base link 9 and interconnecting link 10 are prevented from further rotating as shown in FIG. 19 where the long link 55 extends substantially perpendicular to the upper surface of the lid 53 .
[0112] As the lid 53 is further closed, the sector gear 53 a moves out of meshing engagement with the main gear 59 and the pilot pins 21 a and 21 b move into fitting engagement with the engagement hole 56 a and U-shaped, respectively, thereby placing the LED head 6 in position with respect to the image-forming unit 21 .
[0113] Because the LED head 6 is positioned above the image-forming unit 21 , the compression spring 7 is compressed so that the reaction force of the compression spring 7 is exerted on the interconnecting link 10 , base link 9 , and long link 55 . The interconnecting link 10 , base link 9 , and long link 55 do not buckle but hold the LED head assembly 5 in position relative to the image-forming unit 21 . The compression spring 7 exerts a large reaction force on the LED head 6 , thereby firmly positioning the LED head 6 relative to the image-forming unit 21 . When the lid 53 has been fully closed, the user locks the lid 53 to the body 2 by a fastening, not shown.
[0114] The third embodiment may be applicable to a printer where a pivot pin of the lid extends perpendicular to the longitudinal dimension of the LED heads. In such a printer, as the lid is opened, the LED head assemblies are partially collapsed to facilitate the replacement of the toner cartridge.
[0115] The third embodiment has been described with respect to a case where when the lid is opened, one end of the LED assembly collapses. However, the LED head assembly may be constructed such that the entire LED head assembly collapse just like the first and second embodiments.
[0116] While the first to third embodiments have been described with respect to a case where all of four LED assemblies collapse, the printer may be designed such that only one or two LED head assemblies collapse. A motor can be provided on the body for driving the interconnecting link and base link to collapse, in which case, the mechanism should be designed such that the mechanism move into a collapsed position and an expanded position only when the lid is closed. In other words, the motor is energized such that the mechanism is completely collapsed before the user starts to open the lid and the mechanism starts to move into the expanded position after the lid has been fully closed.
[0117] The first to third embodiments have been described with respect to a case where the LED head assemblies are mounted on the lid of the apparatus. However, the present invention can also be applied to apparatus where the LED head assemblies are provided on the inner lid assembly of the apparatus. Although, the embodiments have been described with respect to an LED head as an exposing unit, the invention may be applied to an apparatus incorporating other type of exposing unit that employs a semiconductor laser.
[0118] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art intended to be included within the scope of the following claims. | An electrophotographic recording apparatus has a lid movable to open and close relative to a body of the apparatus, the lid having an exposing unit mounted thereto. The recording apparatus comprises a collapsible mechanism and a drive mechanism (gear mechanism). The exposing unit is suspended from the collapsible mechanism. The gear mechanism is operatively connected to the lid so that when the lid is opened and closed, the gear mechanism drives the collapsible mechanism to deform selectively into the collapsed position and the expanded position, respectively. When the collapsible mechanism is at the expanded position, the exposing unit is accurately positioned relative to an image-forming unit. When the collapsible mechanism is at the collapsed position, the exposing unit is at a retracted position so that the exposing unit allows easy access to the interior of the apparatus. The gear mechanism may include a torque limiter. | 6 |
FIELD OF THE INVENTION
This invention relates to the pyrolysis of fluoroform (CHF 3 ) to form perfluoroolefins.
BACKGROUND OF THE INVENTION
Tetrafluoroethylene (TFE) can be produced by pyrolysis of CF 2 HCl(F-22) at about 800° C. HCl splits off and two of the remaining CF 2 radicals combine to form CH 2 ═CH 2 . However F-22 is an ozone destroying chemical and other procedures for obtaining TFE are desirable.
In U.S. Pat. No. 3,009,966 fluoroform is converted to TFE and perfluoropropene using high temperatures, short dwell times and low pressures. However the pyrolysis temperatures are limited by the heat tolerance of the reaction vessel, which in the Examples is platinum lined nickel or simply nickel. Indeed, the patent examples use no higher temperatures than 1120° C. (Ex. 60) even though the patent states that temperatures up to 1500° C. may be used. Such a high temperature may be unrealistic since the Examples do not begin to approach that. Furthermore, the patent states at column 2, lines 1-3 that it is difficult to produce the desired products because of the extremely short contact times that must be used.
SUMMARY OF THE INVENTION
It is a purpose of this invention to provide a process for preparing perfluoroolefins especially TFE and perfluoropropene from fluoroform which overcome the deficiencies recited above.
The deficiencies may be overcome by carrying out the pyrolyzation in a flame envelope submerged in water, said flame being at a temperature of between about 1000° C. and 3000° C. and said flame being submerged in water such that the water pressure at the flame point is between about one and thirty inches of water. The surrounding water acts as a reaction vessel.
BRIEF DESCRIPTION OF THE DRAWING
The drawing is a side view, cutaway, of a vessel useful in the process of the invention.
DESCRIPTION OF THE INVENTION
In this invention equipment can be used consisting of a torch similar to a regular oxygen/hydrogen torch, modified so that gaseous nitrogen and gases such as fluoroform can also be fed. Each gas stream is supplied by storage cylinders of the conventional type equipped with conventional pressure reducers, related pressure indicators and also flowmeters.
Referring to the drawing, at the torch supply end 10, all four gas hoses are connected into an enlarged mixing header 11 by the addition of the nitrogen and fluoroform gas supplies. This means bringing two additional, separate connections to the standard system of hydrogen and oxygen mixing. The assembly follows standard practice in which the remainder of the torch is isolated by a small flame arrestor. For convenience, the pipe between the flame arrestor and the nozzle 15 can be extended and bent into an acute 45° angle so as to permit the flame to burn in an upward direction when it is immersed under water.
The water tank 12 is typically five gallon size, it will have a very light transparent, loose cover 13 with a hole 14 for gas venting. This hole is sized by experience with the particular torch employed, in order to vent products in a controlled way without lifting the light transparent cover (which is then in place for explosion release purposes). The gas space below the cover will have automatic gas sampling and an oxygen detector (not shown). This space is also fitted with a UV detector for indication that the flame has gone out. This detector connects to the fail-safe valves for automatic shut down at the cylinders. There is also a temperature indicator in the gas space as another indicator of flame out. The water space is fitted with a pH meter, and a temperature indicator for controlling the supply of water for cooling, and an overflow drain.
In operation, a flame 16 is established in air by igniting the hydrogen supply to the torch nozzle. Oxygen is then turned on and the two gases adjusted to achieve a typical stable oxy-hydrogen flame. This flame is not very luminous so that operation in a darkened area is helpful. Balanced combustion is recognized by the conventional aspect of the flame, whereby a small cone of unburned gas is luminous adjacent to the nozzle.
For subsequent repeatability, the length of the total flame envelope, from the nozzle to the envelope tip together with a description of the colors and pattern of the flame envelope and the cone are all measured and recorded. The objective is to aim for repeating this flame condition in order to optimize subsequent fluorocarbon conversion.
The established, standarized oxy-hydrogen flame is then immersed in the water in the container. Because of the 45° nozzle, the flame is then vertical but if the nozzle goes too deep for the pressure conditions, then the flame will go out. To rectify this problem, a series of different, smaller nozzles with shorter flame lengths are necessary in order to obtain a flame which is completely immersed and burning in a stable manner even though it is under water.
With the flame burning steadily underwater, nitrogen is slowly introduced at an increasing, controlled rate until the flame goes out. The flowrate of the nitrogen at this point, then becomes the basis for continued experimental operation and is called the "flame out rate."
Once again the flame is re-established underwater, but this time nitrogen flow is limited to 80% of flame out rate. This condition is used for a sufficient length of time that the oxygen detector shows that the gas in the space above the water is less than 0.5% oxygen. An inert blanket is thus established over the water and under the lightweight cover.
With the nitrogen at the steady 80% rate, the fluoroform is now added to the flame as the raw material for conversion, at a rate of 1% of the "flame out rate" of the nitrogen. Sampling of the gas space commences almost immediately since this is a process with very small reactor capacity. The flow rate of the fluoroform is increased in 1% steps subsequent to extraction of each satisfactory sample. This increase continues until the flame goes out.
In this way the characteristics of the particular nozzle and flame system (which acts as a complete reactor) are determined. This capability continues with the following steps.
Again the flame is established underwater but now, with steady, similar conditions, nitrogen is fed at a rate of 60% of the flame out rate. Once again fluoroform is fed as raw material, starting at 1% of flame out rate and again increasing this flow in steps interspersed with satisfactory gas sampling. The increases continue until once again the flame is extinguished. Consequently a second set of data steps is obtained for fluoroform conversion this particular nozzle and flame condition.
By continuing the method of stepwise decreasing nitrogen flow, associated with stepwise increases of the fluoroform feed stock, an extensive data set is obtained, and indicates the conditions such as diluent ratio which are optimum for the chosen nozzle and flame with respect to the desired end product such as tetrafluoroethylene.
Once an acceptable optimum yield is obtained and the choice is made not only between different burner nozzles but also with respect to safe operation, a collecting cover is placed on the apparatus. The collecting cover is fitted with an explosion disk and an adjacent piping nozzle for product discharge via a spray trap to subsequent refining equipment. For safety reasons, the product discharge must always be at a positive pressure. The resulting gaseous products are then collected and individually isolated.
In this present invention of submerged pyrolysis the by-product hydrogen fluoride is obtained in aqueous form and is readily available for sale in this form at various concentrations or, by the addition of KOH to the water can precipitate out at potassium fluoride which is an inert solid and therefore more readily convenient as an acceptable material for waste disposal.
In this present invention, where the combustion is submerged, the container for the reaction is the water. Thus water avoids the problems mentioned up to a rate of heat generation which causes excessive localized boiling. Since it is such an inexpensive material, and can be regularly or continuously purged, it in effect makes an excellent material of reactor construction.
In the invention very short contact times are inherent in the nature of the flame envelope and are partly a function of a particular nozzle arrangement. Because the short contact times are inherent, this is one of the features which make this system of submerged reaction desirable.
It is a notable feature of this invention that not only low contact times are inherent in the process of submerged combustion, but at the same time both the presence of oxy-hydrogen combustion and the available variations in nitrogen dilution enable the partial pressure of the fluorocarbon reaction system to be reduced in a very controllable way.
It is noteworthy that in this present invention, though it is impractical to measure the volume of the heated zone, and indeed that volume will vary with the gas flow and flame envelope length, nevertheless, it is an added advantage of this new submerged processing system, that for a given set of stable conditions, the reaction zone is very precisely bounded by the water in which it is contained.
It is the inherent size and dynamics of the submerged flame configuration which fit in so advantageously with the requirements of short contact time of the fluoroform to TFE conversion process. In fact, with flowrates of the gas feeds totalling one cubic foot/minute and with a flame envelope on the order of twelve inches long by half inch diameter, calculations show roughly that total contact times are much less than 0.5 seconds although the rapidly changing chemistry inside the flame envelope coupled with the complications of gaseous expansion due to the unknown thermal profile prevent any reasonably accurate calculation of contact time at reactive temperatures from being carried out.
As previously mentioned, one of the salient advantages of the invention is that it provides a simple and economical method of obtaining high yields and conversions of tetrafluoroethylene and perfluoropropylene direct from fluoroform. To obtain optimum yields and conversions to these two materials it is preferred to employ the combination of relatively high temperatures (preferably, from 1000° to 3000° C.) preferably 1500°-3000° C., short contact time (preferably contact times of from 0.5 to 0.010 second). Relatively high temperatures are preferred in order to increase the rate of reaction (and therefore conversion per pass). Short contact times and sub-atmospheric pressures are preferred since it has been found that these conditions maximize the yield of these two products and minimize the production of other products such as per fluoroisobutylene.
Safety considerations are important in this operation since by-products can be extremely toxic, as they include the possible occurrence of PFIB. PFIB namely, perfluoroisobutylene, is one of the most toxic substances known. Similarly, there is a significant potential for explosions arising not only from TFE decomposition but also from oxygen interaction with unlit hydrogen or from oxygen reacting with TFE or from elemental carbon reacting with oxygen. It must be noted that the presence of fluorine compounds adds many hazards to the situation particularly because of potential oxyfluorine compounds such as COF 2 .
For safety, the cylinder supply system is physically isolated from the reaction area, so relatively long hoses are needed to connect the cylinder system to the torch. Also, power actuated fail-safe valves are required adjacent to and downstream of the pressure reducers. The fail-safe valves must close immediately if a safety problem arises.
For safety, alertness to the flame condition is essential, and this can be determined optically as stated above, or by a sudden increase in the exit gas volume, or by an alarm from an oxygen detector which samples the gas space over the water. When this happens, the oxygen supply must be shut off immediately and be quickly followed by shut off of the hydrogen supply and the CHF 3 supply.
With the flame burning steadily, and a steady CHF 3 supply, pyrolysis is indicated by a pH meter which shows an increase in acidity as HF is formed. However, reactions may go towards the undesirable manufacture of CF 4 and elemental carbon. For this reason the gas space and water overflow (if any) need to be carefully watched for the presence of carbon which in the event, must trigger the same urgent oxy-hydrogen shut down procedure given above.
Much of the above process is a function of the particular choice of hydrogen torch and size of the water reservoir since the oxy-hydrogen flame will heat the water and lead to water loss through evaporation. Also, water will be formed by the reaction so that the net volume of water may or may not lead to a water overflow. | A preparation of perfluoroolefins from fluoroform is described in which the fluoroform is pyrolyzed in a flame submerged in water in which the water acts as the walls of a reaction vessel. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. National Stage of International Application No. PCT/EP2008/059377 filed on Jul. 17, 2008 and claims the benefit thereof. The International Application claims the benefit of GB Application No. 0715281.2 filed on Aug. 7, 2007, both applications are incorporated by reference herein in their entirety.
BACKGROUND OF THE INVENTION
[0002] Described below is a method of reducing the transmission time interval (UI) in enhanced general packet radio service (GPRS) EGPRS networks.
[0003] Currently, radio blocks are divided into four bursts; up to and including in 3GPP GERAN Release 6 the bursts are transmitted on a specific timeslot in four time division multiple access (TDMA) frames. Each TDMA frame is approximately 5 ms in duration, making the transmission time interval approximately 20 ms.
[0004] According to the reduced transmission time interval (TTI) RTTI scheme introduced in Release 7 of the 3rd Generation Partnership Project (3GPP) General Packet Radio Service (GPRS)/ Enhanced Data for global system for mobile communication (GSM) Evolution (EDGE) Radio Access Network (GERAN) 3GPP GERAN standards, timeslots (of which there are eight, numbered 0 through 7, per TDMA frame) can be combined into pairs; then four bursts are transmitted using two (paired) timeslots in each of two TDMA frames, reducing the TTI to approximately 10 ms. The configuration of a pair of timeslots (which may or may not be on the same carrier) is referred to as a packet data channel (PDCH)-pair.
[0005] In the case of downlink dual carrier assignments a mobile can receive on two different carriers simultaneously. This addresses both the case where PDCH-pairs must use timeslots on the same carrier and the case where no such restriction exists (where so-called ‘split PDCH-pairs’ are possible). In the latter case, this concerns only the case where, if PDCH-pairs are on different carriers, the timeslot numbers are the same.
[0006] In general, this considers that PDCH pairs cannot ‘split’ another pair e.g. a pair on 1,3 cannot co-exist with a pair on 2,4.
[0007] It is assumed that in any RTTI configuration, there must be at least one uplink (UL) PDCH pair and one downlink (DL) PDCH pair (even though it is not essential that the mobile has resources assigned on both, they are needed for packet associated control channel (PACCH)).
[0008] Due to the medium access control (MAC) protocols used in GERAN, it is not required that every UL PDCH pair must have a corresponding DL PDCH pair (in such a case, either extended dynamic allocation (EDA) can be used, or a modified shifted uplink status flag (USF) approach can be used see 3GPP TS 44.060 v.7.0.0).
[0009] Similarly, it is not required that every DL PDCH pair must have a corresponding UL PDCH pair: the network is forbidden from polling a mobile on a DL PDCH pair for which no corresponding UL PDCH pair exists.
[0010] The problem here is to communicate efficiently to the mobile which timeslots are configured as PDCH-pairs and on which of these PDCH-pairs the mobile is assigned resources.
[0011] A subset of this problem is to efficiently encode the description of how PDCH-pairs are assigned to different timeslots and, in the case of Downlink Dual Carrier, different carriers.
[0012] It is further necessary to specify how a mobile determines, based on the configuration and/or its assignment, which uplink (UL) and downlink (DL) PDCH-pairs correspond to each other. These so-called ‘corresponding pairs’ govern, for example, on which DL PDCH-pair the mobile should expect to receive an uplink state flag (USF) indicating that it may transmit on a given UL PDCH-pair; also, on which UL PDCH-pair should a mobile respond to a poll sent on a given downlink PDCH-pair.
[0013] Description of PDCH-pairs is separated into a “configuration” and an “assignment”. A mobile may receive a message which describes a change in configuration or assignment or both.
[0014] Broadly speaking, the configuration describes all RTTI PDCH-pairs currently in use on a given carrier (or pair of carriers), and is distinct from timeslots which are used for non-RTTI packet transfer, or for circuit-switched voice or data transfer. The assignment describes the subset of PDCH-pairs on which a given mobile can expect to transmit or receive data, and also specifies various RLC and MAC parameters (uplink state flag, etc.).
[0015] Two methods of encoding the configuration are specified using a bitmap, either fixed or variable length, depending on whether or not ‘split PDCH-pairs’ are permitted.
[0016] Rules for determining which PDCH-pairs are ‘corresponding PDCH-pairs’ are specified, based on either the configuration or the assignment.
[0017] Rules for informing the mobile of a change in assignment or a change in configuration, or both are specified, including the definition of a new message to inform mobiles (possibly a broadcast message) that a configuration has changed, but the assignment remains (broadly) as before, based on the new configuration.
[0018] A mobile may be sent a message describing a modification to an existing assignment, without a corresponding change in configuration, e.g. a downlink assignment message may indicate that the mobile now is assigned resources on downlink PDCH-pairs 1 & 2, instead of on 2 & 3.
[0019] A mobile may be sent a message describing a modification to an existing configuration, without a corresponding change in assignment, e.g., downlink PDCH-pair 3 now uses timeslots 5 & 6, rather than on 5 & 7. Any resources assigned on DL PDCH-pair 3 remain unchanged (but using the new timeslots).
[0020] Since the configuration affects all mobiles using resources on a specific carrier, a message indicating a change of configuration is defined which is a broadcast message. That message may be sent repeatedly to ensure reception and may include a ‘start time’ at which the new configuration will apply.
[0021] The mobile should be informed of the configuration currently being used. The configuration need not be described in subsequent assignment messages if it has not changed.
[0022] PDCH-pairs within a configuration are identified by a number, and the identifying number is increased in order of the timeslot numbers used in the configuration. E.g., PDCH-pair using timeslots 1 & 2 is PDCH-pair number 1, PDCH-pair on timeslots 3 & 5 is PDCH-pair number 2. In order to re-use existing message structures, these identifying numbers are considered equivalent to timeslot numbers in legacy configurations—legacy messages/structures etc. referring to timeslot numbers can be used without change, to refer to PDCH-pairs.
[0023] A default configuration is specified, having 4 PDCH-pairs per carrier, with PDCH pair i (0≦i≦3) using timeslots 2i and 2i+1, both in the UL and DL.
[0024] The described PDCH-pair configuration need not match the actual PDCH-pair configuration, provided that assignments refer only to PDCH-pairs which actually exist. This means that, for example, the default configuration may be indicated even if only a subset of PDCH-pairs in the described configuration exist. This has the benefit of reducing the amount of signaling information both for the default configuration and where the actual configuration changes but, thanks to this rule, no actual notification is required to mobiles.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] These and other objects and advantages of the present invention will become more apparent and more readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which:
[0026] FIG. 1 is a graphic depiction of a first coding example;
[0027] FIG. 2 is a graphic depiction of a second coding example;
[0028] FIG. 3 is a graphic depiction of a third coding example;
[0029] FIG. 4 is a graphic depiction of a coding example regarding ALTERNATIVE 1;
[0030] FIG. 5 is a graphic depiction of a further coding example regarding ALTERNATIVE 1;
[0031] FIG. 6 is a graphic depiction of a coding example regarding ALTERNATIVE 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0032] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.
[0033] Coding of the Configuration Description When Split PDCH-Pairs is Not Permitted
[0034] If split PDCH-pairs are not permitted, then up to four PDCH pairs may be configured on a carrier. These are described in a 7- or 8-bit bitmap as follows . PDCH pair 1 is configured on the two lowest-numbered timeslots whose corresponding bits in the bitmap are set to 1. PDCH pair 2 is configured on the two timeslots with the next lowest timeslot numbers whose corresponding bits in the bitmap are set to 1 and so on. The bit corresponding to timeslot 7 need not be included in the assignment message but can be considered a 1 if there are an odd number of 1's in the included bitmap, otherwise it shall be considered a 0 (since there must be an even number of 1's in the total bitmap).
[0035] For mobiles currently in packet transfer mode or Dual Transfer Mode (i.e. currently having some packet resources), the absence of the UL PDCH Pairs bitmap and DL PDCH pairs bitmap shall indicate that the PDCH pair configuration has not changed since the previous assignment message was received.
[0036] For mobiles currently in packet idle mode or dedicated mode (i.e. having no packet resources), the absence of the UL PDCH Pairs bitmap and DL PDCH pairs bitmap shall indicate that the PDCH pair configuration are according to a default configuration, as follows: on both uplink and downlink, PDCH pair i (0≦i≦3) is on timeslots 2i and 2i+1.
[0037] An explicit indication of the use of the default configuration shall also be specified.
[0038] For existing assignment messages, structures and information elements (IEs) which allocate resources in RTTI mode, and other messages, e.g., measurement report messages, references to Timeslot Numbers shall refer to PDCH Pairs. A message which refers to resources on a PDCH pair that is not known (e.g., for all PDCH pairs 4, 5, 6, 7 which cannot exist for a non-downlink dual carrier configuration) shall be considered to be an error.
[0039] Coding of the Configuration Description When Split PDCH-Pairs is Permitted
[0040] If split PDCH-pairs are permitted then, according to the approach provided herein, a variable-length bitmap is used to code the PDCH-pairs, according to the following algorithm:
[0041] For each timeslot/carrier, starting at TN0 on C1 going through (TN7, C1), then (TN0, C2)−>(TN7, C2):
if this timeslot forms part of a PDCH pair *and* forms part of a split PDCH (i.e. the other timeslot is on a different carrier) *and* the other timeslot in the pair has already been referenced in the bitmap, then skip this timeslot, otherwise:
if this timeslot does not form part of a PDCH pair −> insert 0 in bitmap if this timeslot forms part of a PDCH pair −> insert 1 in bitmap
if the other timeslot which forms part of this PDCH pair has already been denoted in the bitmap proceed to the next timeslot, otherwise if the other timeslot which forms part of this PDCH pair has not already been denoted in the bitmap:
if the other timeslot in this PDCH pair is on the same carrier −> insert 0 in bitmap if the other timeslot in this PDCH pair is on a different carrier but on the same timeslot (i.e. a ‘split PDCH pair’)−> insert 0 in bitmap
[0049] As an option, any trailing zeros can be omitted, if the bitmap is preceded by an indication of its length.
[0050] As a further option, in addition to trailing zeros, the last ‘1’ can be omitted (if the bitmap is always terminated by a 1, then this can be implicit).
[0051] As a further option, a one or two default codes are assigned to indicate that every timeslot forms part of a PDCH, where the first default code indicates that all PDCH-pairs use timeslots on the same carrier and on contiguous timeslots and there are four PDCH-pairs per carrier; the second default code indicates that all PDCH-pairs are split PDCH-pairs, and there are 8 PDCH-pairs per two carriers.
[0000] Coding examples:
[0052] With PDCH pairs on (see FIG. 1 )
[(C1,TN1), (C1,TN2)] [(C1,TN4), (C1,TN5)] [(C1,TN6), (C2,TN6)] [(C2,TN2), (C2,TN3)]
is coded as:
0 1 0 1 0 1 0 1 1 1 0 0 0 1 0 1 (3 trailing zeros omitted)
[0057] PDCH pairs on (see FIG. 2 )
[(C1,TN0), (C2,TN0)] [(C1,TN1), (C1,TN2)] [(C1,TN3), (C2,TN3)] [(C1,TN4), (C2,TN4)]
is coded as:
1 1 1 0 1 1 1 1 1 (8 trailing zeros omitted)
[0062] With PDCH pairs as (see FIG. 3 )
[(C1,TN0), (C2,TN0)] [(C1,TN1), (C1,TN3)] [(C1,TN4), (C2,TN4)] [(C1,TN5), (C2,TN5)]
is coded as:
1 1 1 0 0 1 1 1 1 1 (7 trailing zeros omitted)
[0067] Example coding of default options (using CSN.1 coding):
[0000]
{ 00 -- no PDCH pairs configured (or configuration as per
previously received description)
| 01 -- default option 1
| 10 -- default option 2
| 11 < PDCH Description length : bit (5) > < PDCH Description : bit
(val(PDCH Description length)) > }
[0068] This scheme is beneficial, because it efficiently encodes the arrangement of PDCH pairs in a logical manner. It is logical, insofar as timeslots are processed in order (unless already specified); it is efficient in that it makes use of the redundancy by not encoding timeslots that are known to be part of a PDCH pair when it is a ‘split pair’ and this has already been specified for the other timeslot (which must be on the same timeslot number).
Determining Corresponding PDCH-pairs: ALTERNATIVE 1:
[0069] (1) Default PDCH-pair correspondence is according to the set of PDCH-pairs used in the assignment: The i-th PDCH-pair in the DL assignment corresponds to the i-th PDCH-pair in the UL assignment (for mTBF, these refer to the union of all PDCH-pairs in assignments for all TBFs).
[0070] (2) If there are n DL PDCH-pairs and m UL PDCH-pairs in the assignment, and m>0, n>0,m≠n:
a. if n>m, the jth DL PDCH-pair (j>m) corresponds to the m th UL PDCH-pair.
If there are PDCH pairs on (see FIG. 4 )
Downlink [(C1,TN1), (C1,TN2)] Downlink [(C1,TN4), (C1,TN5)] Uplink [(C2,TN1), (C2,TN2)]
The UL PDCH-pair corresponds to both downlink PDCH-pairs, i.e. a poll on either downlink PDCH-pair is responded to on the single UL PDCH-pair. However, only the USF on the first downlink PDCH-pair signals an UL allocation. An alternative is that there is no corresponding UL PDCH-pair; network is never allowed to poll on this PDCH-pair.
b. if m>n , the j-th UL PDCH-pair (j>n) corresponds to the m-th DL PDCH-pair.
An example is shown in FIG. 5 :
Downlink [(C1,TN1), (C1,TN2)] Uplink [(C2,TN1), (C2,TN2)] Uplink [(C2,TN4), (C2,TN5)]
In the example above, there are two options: i) use Extended Dynamic Allocation (EDA) to signal allocations on the two
[0085] UL PDCH-pairs;
ii) use a modified ‘shifted USF’ approach i.e. define two separate USFs to be sent on the DL PDCH-pair which correspond to each of the two UL PDCH-pairs.
[0087] (3) UPLINK_CONTROL_TIMESLOT can be re-used to mean UPLINK_CONTROL_PDCH_PAIR.
[0088] (4) If n=0 (i.e. no DL PDCH-pairs in the assignment), then the corresponding PDCH-pair is found according to Alternative 2, see below.
Determining Corresponding PDCH-Pairs: ALTERNATIVE 2:
[0089] (1) Default PDCH-pairs correspondence is according to the timeslots used in the PDCH pair configuration. For an UL PDCH pair using timeslots i and j (i<j), the corresponding downlink pair is
a. the one which uses DL timeslot i and some other timeslot k, k>i, or, if that does not exist, b. the one which uses DL timeslot i−1 and some other timeslot k, k≧i ; or, if that does not exist, c. keep searching by increasing x (starting at 1) for a PDCH pair which uses DL timeslot i−x and some other timeslot k, k>i−x.
[0093] An example is shown in FIG. 6 :
Downlink [(C1,TN3), (C1,TN5)] Downlink [(C1,TN6), (C1,TN7)] Uplink [(C2,TN4), (C2,TN5)]
[0097] In the above example, the DL PDCH-pair on 3, 5 corresponds to UL PDCH pair on 4, 5.
[0098] Note that the above search may find nothing (you get to the beginning of the frame); in this case, search forward until you find a PDCH-pair in the DL; in the above example, if the PDCH-pair on 3,5 did not exist, then the PDCH-pair on 6,7 would be the corresponding pair.
Changing Assignments/Configurations
[0099] It is likely that over time, a mobile's assignment will change, also that the cell RTTI configuration will change. These can change independently of each other or jointly.
[0100] Considering four possible cases:
a. The configuration changes, the assignment doesn't change [the timeslots used for the PDCH-pairs which make up the assignment do not change]. In this case, the PDCH-pair numbers may change; this will have no impact except for measurement reports. The mobile report will have to use the new PDCH-pair numbers, rather than the old numbers.
In this case, a new message is required to notify the mobile of the new configuration.
b. The configuration changes, and as a direct result, the assignment changes [the timeslots used for the PDCH-pairs which make up the assignment do change]. A new assignment message is not needed if:
i) resources (inc. USFs) on PDCH-pair i remain on PDCH-pair i; and, ii) resources on PDCH-pairs (including, in the case of DL PDCH-pairs, their USFs) which no longer exist in the new configuration are implicitly released; iii) all remaining corresponding pairs (i.e. not those involving pairs released under rule 2 above) remain the same (i.e. DL PDCH-pair i and UL PDCH-pair j were corresponding pairs before and after the re-configuration).
In this case, a new message is required to notify the mobile of the new configuration.
c. The assignment and the configuration change. In this case, a new assignment message, including a description of the new configuration is required. d. The assignment changes, but the configuration does not change. In this case a new assignment message is required; the configuration description may be omitted.
[0110] Further advantages include that
by specifying a way of calculating the corresponding pairs based on the configuration and/or assignment information, no additional signaling is required between the network and the mobile; by defining a new message to indicate that the configuration has changed, but the assignment has not (except for some implicit indications) no new assignment message is needed, thereby reducing signaling; by specifying that the configuration information should be sent to mobiles in addition to the assignment information, the new message may be broadcast to multiple devices where the assignment information has not changed, further reducing signaling; and
by specifying a default configuration reduces the average amount of signaling for RTTI messages, since this default configuration would use a very short code but would be applicable in many scenarios.
[0114] The invention has been described in detail with particular reference to preferred embodiments thereof and examples, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention covered by the claims which may include the phrase “at least one of A, B and C” as an alternative expression that means one or more of A, B and C may be used, contrary to the holding in Superguide v. DIRECTV, 69 USPQ2d 1865 (Fed. Cir. 2004). | A method is suggested for communicating to a mobile station which timeslots are configured as packet data channel pairs and on which of these packet data channel pairs the mobile station is assigned resources, wherein a description of packet data channel pairs is separated into “configuration” and an “assignment”. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a Continuation-in-Part of U.S. application Ser. No. 08/857,133, filed May 15, 1997 now U.S. Pat. No. 5,816,155 which is a continuation of Ser. No. 08/595,103 filed Feb. 1, 1996.
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a sheet guiding device for printing presses having guide surface members with slit nozzles for receiving and transmitting blast air. The slit nozzles are aimed in a direction crosswise to a sheet travel path.
A sheet guiding device of this general type has become known heretofore from the published German Patent Document DE 34 11 029 C2. In this known sheet guiding device, an attempt has been made to achieve a reliable floating or suspended guidance of the sheets by using nozzles having different blowing directions. A floating sheet guidance device must be used during two-sided printing to avoid smearing of the ink along the guide faces, however, it has disadvantages. It is either difficult or not at all possible to obtain a floating guidance for unstable sheets, especially sheets with low weight or a low density (less than 100 g/m 2 ). Additional problems arise at high machine speeds due to arising centrifugal forces which make clean sheet guidance via the floating guide difficult.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a sheet guiding device for printing presses which overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type, and which provides a floating guiding device which can process sheets with a low weight and/or a low density (less than 100 /m 2 ).
With the foregoing and other objects in view there is provided, in accordance with the invention, a sheet guiding device for a printing press, having guide surface members with slit nozzles for emitting blast air, the slit nozzles are aimed in a direction to an outside of (crosswise to) a sheet travel path.
In accordance with an added feature of the invention, the slit nozzles have an air blowing direction and the air blowing direction is essentially perpendicular to the sheet travel path.
In accordance with another feature of the invention, the guide surface members have an area and the area is occupied by a different degree of concentration of the nozzles to suit the particular air requirement for keeping sheets taunt.
A further feature provides that the guide surface members be arrayed with a varying number of nozzles or a varying density thereof per unit area to suit or match the particular air requirement for keeping the sheets taunt. For example, it is thus possible for the entry and exit regions of the guide surface members to be provided with a greater density of nozzles per unit area or a higher degree of occupancy by nozzles in the respective area, while the guide zone(s) located between those regions have a lower nozzle density or degree of occupancy per unit area. It is also possible for the nozzle density or degree of areal occupancy to be provided greatest in the middle of the sheet travel path and to decrease toward the edge or sides thereof. This is especially expedient if the nozzles are slit nozzles directed towards the outside of the sheet travel path. Then, the corresponding air flow is generated in the middle of the sheet travel path and need merely be maintained towards the edge; that is, as many nozzles as in the middle of the sheet travel path are no longer needed.
In accordance with an additional feature of the invention, there are axial fans and/or adjustable-speed fans for supplying air to the slit nozzles. The air supply to the nozzles is preferably accomplished via the adjustable-speed fans. In this manner, in the blowing or blast mode, the floating or suspension guidance can be adjusted.
In accordance with yet another added feature of the invention, there are air supply chests for effecting a supply of air to the slit nozzles.
In accordance with yet another feature of the invention, there is an axial fan assigned to each of the air supply chests.
In accordance with another additional feature of the invention, the slit nozzles are stamped into the guide surface members.
In accordance with a concomitant feature of the invention there is a central air supply provided with blowing air for supplying air to the slit nozzles.
It is possible to have the desired air act upon relatively large nozzles individually by the fans, or an air supply can be provided wherein individual regions or portions of the air supply are made effective via air supply chests or boxes, to each of which an air supply is assigned. Naturally, a further subdivision is also possible, depending upon how strong the action of the air in a certain region is required. The advantage of the air supply chests or boxes is that many nozzles can be supplied by one air supply element. For a relatively large number of nozzles, for example, correspondingly strong axial fans can be used. Due to the subdivision, it is nevertheless possible to supply air variably to the individual regions. It is therefore proposed that an axial fan be assigned to each blower chest, and that the size of the air supply chests be adapted to the air requirement of the respective region.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a sheet guiding device for printing presses, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a diagrammatic side elevational view of a printing press provided with a sheet guiding device according to the invention;
FIG. 2 is an enlarged fragmentary view of FIG. 1 showing a guide surface of a transfer drum of the printing press in accordance with the invention;
FIG. 3 is a developed top plan view of the sheet guiding device formed of air supply boxes in accordance with the invention;
FIGS. 4, 5 and 6 are different arrangements of axial fans in the air supply boxes;
FIG. 7 is a nozzle array in the air supply boxes;
FIGS. 8 and 8 a are respective cross-sectional and plan views of a slit nozzle in accordance with the invention; and
FIG. 9 is a view similar to that of FIG. 3 showing a guide surface wherein sucking of a sheet occurs in sections disposed centrally to a longitudinal axis of the sheet.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and, first, particularly to FIG. 1 thereof, there is shown therein diagrammatically a printing press with an exemplary embodiment of a sheet guiding device according to the invention. In the interest of simplicity, only two printing units 20 and 20 ′ of the printing press are shown; generally, such a printing press has four printing units or more. Each printing unit 20 , 20 ′ has an impression cylinder 8 , 8 ′, a rubber blanket cylinder 9 , 9 ′, and a plate cylinder 10 , 10 ′, as well as non-illustrated inking units. Between the printing units 20 and 20 ′, a transfer drum 6 assures the further passage of the sheets 4 to be printed. If a printing press has several printing units, transfer drums 6 are always disposed between each two printing units. Naturally, it is also possible for a plurality of sheet feeding drums to be provided instead of the single transfer drum 6 . In the illustrated printing press, a sheet travel path 17 is shown with accompanying arrows 24 indicating the sheet travel direction. The sheets 4 are removed from a feed pile 19 and forwarded, by a conventional non-illustrated feeder device, to a feeder drum 5 having non-illustrated grippers with which it transfers the sheets 4 to an impression cylinder 8 for printing. From the impression cylinder 8 , the sheet 4 is accepted by grippers 26 (FIG. 2) of the transfer drum 6 and delivered to a further impression cylinder 8 ′, so that a further printing operation can be performed on the sheet 4 . In the illustrated printing press, the impression cylinder 8 ′ transfers the sheet 4 to a delivery drum 7 of a delivery system 21 . The delivery drum 7 is a transfer drum having gripper bars which are disposed on a delivery chain 22 and which transport the accepted sheets 4 to the end of the delivery system 21 , whereat the sheets 4 are deposited on a delivery pile 23 .
Additional sheet guidance is required in sections 3 of the printing press so that the sheets 4 will be transported cleanly and, above all, transferred to the impression cylinders 8 and 8 ′ so as to lie smoothly thereon. In this regard, guide surface members or deflectors 1 having a number of preferably slitlike nozzles 2 are disposed in the sections 3 . These nozzles are not shown in FIG. 1 but can be seen, for example, at the transfer drum 6 in FIG. 2 . The guide surface member 1 at the transfer drum 6 has a total of four nozzle regions 11 , 12 , 40 and 42 , divided by partitions 44 , 46 and 48 , and acted upon with air by a respective axial fan 15 . The nozzle regions 11 , 12 , 40 and 42 are formed of a plurality of nozzles 2 , which are disposed behind one another as seen in the viewing direction of FIG. 2 . The arrows 25 indicate the possible directions in which the respective axial fans 15 blow. The sheet 4 which has been accepted or taken over by the transfer drum 6 from the impression cylinder 8 by a row of grippers 26 is transported onwardly to the impression cylinder 8 ′.
When the sheet guiding device is in the blowing or blast mode, the sheet 4 experiences a floating or suspension guidance wherein it is guided between the transfer drum 6 and the guide surface member 1 without contacting the surface of the guide surface member 1 . Such a floating guidance is necessary in perfector printing, for example, because neither side of the sheet 4 must be allowed to become smeared at the transfer drum 6 or at the guide surface members 1 .
It is believed to be apparent from FIG. 1 that the axial fans 15 are also disposed at the feeder drum 5 in the entry region 11 and the exit region 13 , respectively, and can apply suction air to the nozzles 2 so as to permit taut sheet guidance there as well, and thereby ensuring that the sheet 4 lies properly on the impression cylinder 8 . One of the axial fans 15 is also provided at the delivery drum 7 and assures that an end of a sheet in this region is reliably guided and cannot fall downwardly if the press should stop, which could consequently cause a creasing of the sheet 4 and render it unuseable. Further apparent is how additional axial fans 15 for sheet guidance can be disposed in the section 3 of the delivery system 21 and can serve, respectively, to feed the sheet 4 reliably to the delivery pile 23 , and to assure that the sheets are acted upon with blown or blast air above the delivery pile 23 in such a manner that they are deposited quickly on the delivery pile 23 .
FIG. 3 shows a guide surface member 1 having the nozzles 2 which are acted upon with air supplied by air supply boxes or chests 16 and 16 ′. The guide surface member 1 is shown in a plan view in FIG. 3, wherein the lines illustrate the subdivision of the guide surface member 1 into the various air supply boxes or chests 16 and 16 ′. The density per unit of surface area of the nozzles 2 which are embodied as slit nozzles 18 is varied. In the entry region 11 , for example, two air supply boxes or chests 16 are provided, which have a relatively high density of nozzles 2 per unit of surface area. They are followed by a guide zone 14 having a varied density of nozzles 2 which is greater in a middle region thereof than at the edges thereof. The guide zone 14 corresponds to the nozzle regions 40 and 42 , wherein an application of blown or blast air is adequate for any operating mode of the printing press. Then follows again a region, which has a higher density of nozzles, which is the exit region 12 , wherein relatively strong holding or retention forces must act upon the sheet 4 in the suction-air operating mode.
FIG. 4 shows how the axial fans 15 can be arranged with the air supply chests 16 and 16 ′ shown in FIG. 3 . It is also possible, however, to provide an arrangement of air supply chests 16 and 16 ′ and of axial fans 15 in the manner shown in FIG. 5 .
If a lesser amount of air is required, one of the subdivisions can be dispensed with, so that only one blower chest 16 ″, respectively, is provided in the entry region 11 and in the exit region 12 , and a large blower chest 16 ′″ is provided in the guide zone 14 , as shown in FIG. 6 . The nozzle array is formed accordingly and is represented in FIG. 7 .
FIGS. 8 and 8 a show the preferred embodiment of the nozzles 2 which have already been indicated in FIG. 3 . This involves slit nozzles 18 , which can be stamped in a relatively simple manner into the sheet metal of the guide surface members 1 . In the arrangement shown in FIG. 3, the direction of blowing is directed outwardly (crosswise to the sheet travel direction) as represented by arrows, which tautens the sheet 4 transversely or crosswise to the travel direction thereof. To that end, it is necessary for two strong, outwardly directed air flows to be formed in the middle and move towards the side of the sheet 4 , those air flows, as they travel towards the outside, being maintainable by using a lesser number of nozzles 2 , 18 .
The exemplary embodiments merely illustrate possibilities for constructing the sheet guiding device of the invention; other constructions with different nozzle arrays and, if necessary or desirable, other blowing or blast directions are also conceivable within the scope of the invention. Instead of the axial fans 15 , a central air supply with blown or blast air and suction air or different types of fans may also be used. | A sheet guiding device for a printing press, includes guide surface members having slit nozzles for emitting blast air. The slit nozzles are aimed in a direction crosswise to a sheet travel path for tautening sheets traveling in the printing operation. | 1 |
BACKGROUND OF THE INVENTION
Electronic data processing and communications equipment is frequently utilized to handle confidential data which is to be kept secret from unauthorized disclosure. The need exists for a simple yet effective means of preventing surreptitious entry into terminal-like devices which house sensitive electronic circuits, keys and codes. Moreover, should physical entry into the device be made, it is essential that the data stored therein be destroyed to prevent the intruder from having access thereto.
The interlock means provided by the present invention fills this security need.
SUMMARY OF THE INVENTION
The present invention finds particular application in secure data communications terminals, although it is not to be considered limited thereto. In such an application, there is provided an input-output cable assembly selected to be interlocked. After being fitted with a special interlock plate, the connector plug of the cable assembly is joined with its mating connector receptacle which is mounted on a board affixed to the terminal back plane. Access to the connector receptacle is had by way of an opening in the cover of the terminal set. This opening is surrounded by an outwardly projecting wall which is preferably formed in one piece with the remainder of the cover. The wall portion encompasses the interlock plate when the latter is operatively positioned, thereby preventing tampering with the perimeter of the interlock plate and its cable assembly.
Installation of the interlock plate and assembly within the cover wall portion, results in the actuation of an electrical switch by means of pressure applied to the switch contact button by the interlock plate. This action completes an electrical circuit which permits an encrypted key or code to be loaded into the terminal. If the cable and interlock plate are removed, the electrical circuit is opened and the key or code destroyed.
In order to prevent the unauthorized removal of the terminal cover to the extent that access to the electrical switch button might be had, the fasteners which hold the cover to the back plane mounting board are located behind the interlock plate. Removal of the cover fasteners, which then permits disassembly of the terminal housing, can only take place if the cable assembly and plate are removed. As noted hereinbefore, this action eradicates the code stored in the terminal.
The terminal housing encloses the top and the sides of the device with the exception of the side enclosed by the access cover. The housing includes tabs at respective side corners thereof which are adjacent to the cover. These tabs cooperate with fasteners in securing the housing to the device. The access cover is formed with inwardly projecting members which obscure the housing fasteners when the cover is in place and prevent the removal thereof.
In summary, a single interlock means in accordance with the present invention prevents access to the interior of the terminal set while the cable assembly is in place, and removal of the assembly destroys the data being stored in the set. These and other features of the invention will become more fully apparent in the detailed description of the interlock means and its mode of operation, which follows.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is an exploded view of an electronic device depicting its housing back plane and access cover with the cable assembly and interlock plate installed in their operative position.
FIG. 2 is an exploded view of the device cover, the cable assembly and interlock plate prior to their being fitted to each other.
FIG. 3 is a section view taken along the lines 3--3 of FIG. 1 depicting especially the relationship of the electrical switch to the interlock plate.
FIG. 4 is a section view taken along the lines 4--4 of FIG. 3 depicting the relationship of the back plane mounting board, the cable assembly with its mating connector, the cover and interlock plate.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates in highly simplified form an electronic device 10 such as a data communications terminal. The back plane 12 has affixed thereto a mounting board 14. Fastened to the latter are connector receptacle means 16 and a push button switch 18. The latter is assumed to be connected by electrical conductors between a source of power and memory circuits and registers (not shown) housed within the terminal.
The rear cover 20 which in device operation is mounted in close proximity to the back plane 12 and its mounting board 14 is illustrated. The connector plug 22 of cable assembly 24 is shown fitted within an interlock plate 26, which in turn has been inserted within a well 28 whose sides 30 project outward from the surface of the cover 20. An electrical cable 32' enters the connector 22. The details of the cable assembly 24 and interlock plate 26 are both seen in FIG. 2.
FIG. 1 also depicts a housing 11 for the device 10 which encloses the top and the sides thereof with the exception of the side enclosed by the access cover 20. The housing 11 is formed with a pair of tabs 13 proximately situated at respective side corners thereof which lie adjacent the cover 20 when the latter is in place. Each of the tabs has an opening to accept a screw 15 for securing the housing to the device. The cover 20 is formed with inwardly projecting members 17 which obscure the screws 15 and prevent their removal when the cover is operatively positioned.
With reference to FIG. 2, there is illustrated the cover section 20 of the terminal device 10. Extending outward from the surface of the cover 20, and preferably formed in one piece therewith, is a unitary wall-like structure, whose sides 30 define a generally rectangular box or well 28. The innermost portion of the well is comprised of two adjacent sections 32 and 34. The first section 32 includes a substantially rectangular aperture 36 in the cover wall to permit connector means 22 associated with the cable assembly 24 to be interlocked, to be plugged into the mating connector means 16 situated on the back plane mounting board 14. The other section, 34 which is substantially rectangular in form, is comprised of the same material as the remainder of the cover 20. This second section includes a centrally disposed slot-like aperture 38 which intersects the rectangular aperture 36 of the first section, and is countersunk on its reverse side. Also, the last section includes on either side of aperture 38, openings 40 which are recessed to accommodate the heads of the cover mounting screws 42, as also seen in FIGS. 3 and 4. These screws permit the cover 20 to be fastened to the back plane mounting board 14, and access to the interior of the terminal set cannot be had without the first removal of these screws.
The cable assembly 24 comprises connector plug 22. As illustrated the plug and receptacle may be the well-known type RS 232C interface connector. The interlock plate 26 is a generally "U" shaped member, having a slot 44 in each of its opposite legs 46. In placing the connector plug 22 into the interlock plate 26, the flanges 48 of the connector fit within the respective slots 44, and the body of the connector 22 rests upon the flat surface 50 of the central portion of the plate 26.
With continued general reference to FIG. 2 and particular reference to FIGS. 3 and 4, the terminal device is readied for operation by attaching the rear cover 20 to the mounting board 14. This is accomplished by screws 42 which pass through apertures 40 into captive nuts 52 affixed to the mounting board 14. As seen in FIGS. 3 and 4, and in phantom in FIG. 2, the cover 20 includes on the side of the cover opposite to the well 28, a frame-like projection 54 which permits, after installation, firm contact between the cover 20 and the mounting board 14; shields the connector means 16 and 22; and serves as a spacing element for the proper joinder of the connector means.
When screws 42 are fully advanced, their heads are within the respective recesses 56 associated with apertures 40. This arrangement eliminates any physical interference with the subsequent insertion of the interlock plate 26 and cable assembly 24 into the well 28. With the cover 20 installed, the actuating push button 18a of switch 18 protrudes through opening 38 into the well. It may be assumed for purpose of example, that the switch contacts are open circuited at this time.
The flanges 48 of connector 22 are then inserted into the respective slots 44 of the interlock plate 26. The plate 26 and assembly 24 are inserted into the well 28, where the connector portions are joined together. The periphery of the inner surface of the plate 26 now bears against the surface of section 34, and a coplanar ledge 58 as seen in FIG. 2 which surrounds the remaining sides of rectangular opening 36.
At this time, push button 18a is depressed by the inner surface of plate 26, as seen in FIG. 3, thereby closing the contacts within switch 18 and establishing an electrical circuit. The latter circuit which includes a source of power permits the insertion and maintenance of secure information and codes into the terminal via additional input means, (not shown). Interruption of this electrical circuit, such as by release of pressure on the push button 18a, immediately eradicates all of the information within the terminal 10.
In conclusion, it is apparent that the interlock system disclosed herein offers an efficient, economical solution to the problem of protecting secure data communication terminals and similar equipments. The inventive concepts and implementation described herein are directed to a specific application. In their applications, changes and modifications of the interlock may be needed to suit particular requirements. Such variations as are within the skill of the designer, and which do not depart from the true scope and spirit of the invention are intended to be covered by the following claims. | Interlock means are described for protecting against the surreptitious entry into, and tampering with security type communication systems. A connector interlock plate is provided which prevents the removal of an access cover on the electronic device cabinet without the first removal of a standard cable connector assembly. Concurrently, removal of the cable assembly actuates an electrical switch which destroys the confidential information being stored and processed within the device. | 7 |
RELATED APPLICATION
The present application claims priority from U.S. Provisional Patent Application Ser. No. 61/794,466, file on Mar. 15, 2013 and which is hereby incorporated by reference in its entirety.
BACKGROUND
The present application is generally related to the field of communications relating to an inground device and, more particularly, to advanced inground device communication power control and associated methods.
While not intended as being limiting, one example of an application which involves the use of an inground device or transmitter is Horizontal Directional Drilling (HDD). The latter can be used for purposes of installing a utility without the need to dig a trench. A typical utility installation involves the use of a drill rig having a drill string that supports a boring tool, serving as one embodiment of an inground tool, at a distal or inground end of the drill string. The drill rig forces the boring tool through the ground by applying a thrust force to the drill string. The boring tool is steered during the extension of the drill string to form a pilot bore. Upon completion of the pilot bore, the distal end of the drill string is attached to a pullback apparatus which is, in turn, attached to a leading end of the utility. The pullback apparatus and utility are then pulled through the pilot bore via retraction of the drill string to complete the installation. In some cases, the pullback apparatus can comprise a back reaming tool, serving as another embodiment of an inground tool, which expands the diameter of the pilot bore ahead of the utility so that the installed utility can be of a greater diameter than the original diameter of the pilot bore.
Steering of a boring tool can be accomplished in a well-known manner by orienting an asymmetric face of the boring tool for deflection in a desired direction in the ground responsive to forward movement. In order to control this steering, it is desirable to monitor the orientation of the boring tool based on sensor readings obtained by sensors in the transmitter that is itself carried by a housing that forms part of the boring tool or other inground tool. The sensor readings, for example, can be modulated onto a locating signal that is transmitted by the transmitter for reception above ground by a portable locator or other suitable above ground device. One class of prior art transmitters is battery powered. It should be appreciated that an inground operation is generally adversely affected by draining the batteries to a degree that renders the transmitter as inoperable, resulting in the need to enter a time consuming process to trip the transmitter out of the ground simply to replace the batteries. While the prior art includes approaches for attempting to conserve and/or enhance battery power, Applicants have discovered additional limitations and concerns relating to battery powered transmitters that are submitted to be unrecognized by the prior art and which are discussed in detail hereinafter.
The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.
SUMMARY
The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements.
In an aspect of the disclosure, a transmitter and associated method are described in which the transmitter is powered by a battery and configured for installation in one of a plurality of different housings each of which housings is characterized by a different housing design and each of which can form part of an inground tool for performing an inground operation in which a drill string extends from a drill rig to the inground tool. A regulator forms part of the transmitter for generating a regulated voltage from the battery. An antenna driver is powered from the regulated voltage for electrically driving an antenna to emanate an electromagnetic signal for remote reception based on power consumption from the battery via the regulator. A controller is configured for limiting the power consumption so as not to exceed a power consumption threshold, irrespective of installation of the transmitter in housings where the transmitter would otherwise exhibit a different power consumption for such housings based on each housing design exhibiting a different housing-attributable signal attenuation of the electromagnetic signal.
BRIEF DESCRIPTIONS OF THE DRAWINGS
Example embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be illustrative rather than limiting.
FIG. 1 is a diagrammatic view of an embodiment of a system for performing an inground operation which utilizes an inground transmitter or electronics package with advanced transmit power control in accordance with the present disclosure.
FIG. 2 is a block diagram that illustrates an embodiment of an electronics package for use in an inground device or tool in accordance with the present disclosure.
FIG. 3 a is a diagrammatic view, in perspective, showing an embodiment of a housing for receiving an electronics package in accordance with the present disclosure.
FIG. 3 b is an exploded diagrammatic view, in perspective, showing the electronics package in relation to a housing cover and body.
FIG. 4 is a flow diagram illustrating an embodiment of a method for operating an inground device in accordance with the present disclosure.
FIG. 5 is a flow diagram illustrating another embodiment of a method for operating an inground device in accordance with the present disclosure.
DETAILED DESCRIPTION
The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements. Various modifications to the described embodiments will be readily apparent to those skilled in the art and the generic principles taught herein may be applied to other embodiments. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features described herein including modifications and equivalents. It is noted that the drawings are not to scale and are diagrammatic in nature in a way that is thought to best illustrate features of interest. Descriptive terminology may be adopted for purposes of enhancing the reader's understanding, with respect to the various views provided in the figures, and is in no way intended as being limiting.
Turning now to the drawings, wherein like items may be indicated by like reference numbers throughout the various figures, attention is immediately directed to FIG. 1 , which illustrates one embodiment of a system for performing an inground operation, generally indicated by the reference number 10 . The system includes a portable device 20 that is shown being held by an operator above a surface 22 of the ground as well as in a further enlarged inset view. It is noted that inter-component cabling within device 20 has not been illustrated in order to maintain illustrative clarity, but is understood to be present and may readily be implemented by one having ordinary skill in the art in view of this overall disclosure. Device 20 includes a three-axis antenna cluster 26 measuring three orthogonally arranged components of magnetic flux indicated as b x , b y and b z . One useful antenna cluster contemplated for use herein is disclosed by U.S. Pat. No. 6,005,532 which is commonly owned with the present application and is incorporated herein by reference. Antenna cluster 26 is electrically connected to a receiver section 32 . A tilt sensor arrangement 34 may be provided for measuring gravitational angles from which the components of flux in a level coordinate system may be determined.
Device 20 can further include a graphics display 36 , a telemetry arrangement 38 having an antenna 40 and a processing section 42 interconnected appropriately with the various components. The telemetry arrangement can transmit a telemetry signal 44 for reception at the drill rig. The processing section can include a digital signal processor (DSP) or any suitable processor that is configured to execute various procedures that are needed during operation. It should be appreciated that graphics display 36 can be a touch screen in order to facilitate operator selection of various buttons that are defined on the screen and/or scrolling can be facilitated between various buttons that are defined on the screen to provide for operator selection. Such a touch screen can be used alone or in combination with an input device 48 such as, for example, a keypad. The latter can be used without the need for a touch screen. Moreover, many variations of the input device may be employed and can use scroll wheels and other suitable well-known forms of selection device. The processing section can include components such as, for example, one or more processors, memory of any appropriate type and analog to digital converters. As is well known in the art, the latter should be capable of detecting a frequency that is at least twice the frequency of the highest frequency of interest. Other components may be added as desired such as, for example, a magnetometer 50 to aid in position determination relative to the drill direction and ultrasonic transducers for measuring the height of the device above the surface of the ground.
Still referring to FIG. 1 , system 10 further includes drill rig 80 having a carriage 82 received for movement along the length of an opposing pair of rails 83 . An inground tool 90 is attached at an opposing end of a drill string 92 . By way of non-limiting example, a boring tool is shown as the inground tool and is used as a framework for the present descriptions, however, it is to be understood that any suitable inground device may be used such as, for example, a reaming tool for use during a pullback operation or a mapping tool. Generally, drill string 92 is made up of a plurality of removably attachable drill pipe sections such that the drill rig can force the drill string into the ground using movement in the direction of an arrow 94 and retract the drill string responsive to an opposite movement. Each drill pipe section or rod can include a box fitting at one end and a pin fitting at an opposing end in a well-known manner. The drill pipe sections can define a through passage for purposes of carrying a drilling mud or fluid that is emitted from the boring tool under pressure to assist in cutting through the ground as well as cooling the drill head. Generally, the drilling mud also serves to suspend and carry out cuttings to the surface along the exterior length of the drill string. Steering can be accomplished in a well-known manner by orienting an asymmetric face 96 of the boring tool for deflection in a desired direction in the ground responsive to forward, push movement which can be referred to as a “push mode.” Rotation or spinning of the drill string by the drill rig will generally result in forward or straight advance of the boring tool which can be referred to as a “spin” or “advance” mode.
The drilling operation is controlled by an operator (not shown) at a control console 100 (best seen in the enlarged inset view) which itself includes a telemetry transceiver 102 connected with a telemetry antenna 104 , a display screen 106 , an input device such as a keyboard 110 , a processing arrangement 112 which can include suitable interfaces and memory as well as one or more processors. A plurality of control levers 114 , for example, control movement of carriage 82 . Telemetry transceiver 102 can transmit a telemetry signal 116 to facilitate bidirectional communication with portable device 20 . In an embodiment, screen 106 can be a touch screen such that keyboard 110 may be optional.
Device 20 is configured for receiving an electromagnetic locating signal 120 that is transmitted from the boring tool or other inground tool. The locating signal can be a dipole signal. In this instance, the portable device can correspond, for example, to the portable device described in any of U.S. Pat. Nos. 6,496,008, 6,737,867, 6,727,704, as well as U.S. Published Patent Application no. 2011-0001633 each of which is incorporated herein by reference. In view of these patents, it will be appreciated that the portable device can be operated in either a walkover locating mode, as illustrated by FIG. 1 , or in a homing mode having the portable device placed on the ground, as illustrated by the U.S. Pat. No. 6,727,704. While the present disclosure illustrates a dipole locating field transmitted from the boring tool and rotated about the axis of symmetry of the field, the present disclosure is not intended as being limiting in that regard.
Locating signal 120 can be modulated with information generated in the boring tool including, but not limited to position orientation parameters based on pitch and roll orientation sensor readings, temperature values, pressure values, battery status, tension readings in the context of a pullback operation, and the like. Device 20 receives signal 120 using antenna array 26 and processes the received signal to recover the data. It is noted that, as an alternative to modulating the locating signal, the subject information can be carried up the drill string to the drill rig using electrical conduction such as a wire-in-pipe arrangement. In another embodiment, bi-directional data transmission can be accomplished by using the drill string itself as an electrical conductor. An advanced embodiment of such a system is described in commonly owned U.S. application Ser. No. 13/733,097, now published as U.S. Published Application no. 2013/0176139, which is incorporated herein by reference in its entirety. In either case, all information can be made available to console 100 at the drill rig.
FIG. 2 is a block diagram which illustrates an embodiment of an electronics package, generally indicated by the reference number 200 , which can be supported by boring tool 90 . The electronics package can include an inground digital signal processor 210 . A sensor section 214 can be electrically connected to digital signal processor 210 via an analog to digital converter (ADC) 216 . Any suitable combination of sensors can be provided for a given application and can be selected, for example, from an accelerometer 220 , a magnetometer 222 , a temperature sensor 224 and a pressure sensor 226 which can sense the pressure of drilling fluid prior to being emitted from the drill string and/or within the annular region surrounding the downhole portion of the drill string. In an embodiment which implements communication to the drill rig via the use of the drill string as an electrical conductor, an isolator 230 forms an electrically isolating connection in the drill string and is diagrammatically shown as separating an uphole portion 234 of the drill string from a downhole portion 238 of the drill string for use in one or both of a transmit mode, in which data is coupled onto the drill string, and a receive mode in which data is recovered from the drill string. In some embodiments, the electrical isolation can be provided as part of the inground tool. The electronics section can be connected, as illustrated, across the electrically insulating/isolating break formed by the isolator by a first lead 250 a and a second lead 250 b which can be referred to collectively by the reference number 250 . For the transmit mode, an isolator driver section 330 is used which is electrically connected between inground digital signal processor 210 and leads 250 to directly drive the drill string. Generally, the data that can be coupled into the drill string can be modulated using a frequency that is different from any frequency that is used to drive a dipole antenna 340 that can emit aforedescribed signal 120 ( FIG. 1 ) in order to avoid interference. When isolator driver 330 is off, an On/Off Switcher (SW) 350 can selectively connect leads 250 to a band pass filter (BPF) 352 having a center frequency that corresponds to the center frequency of the data signal that is received from the drill string. BPF 352 is, in turn, connected to an analog to digital converter (ADC) 354 which is itself connected to digital signal processing section 210 . In an embodiment, a DC blocking anti-aliasing filter can be used in place of a band pass filter. Recovery of the modulated data in the digital signal processing section can be readily configured by one having ordinary skill in the art in view of the particular form of modulation that is employed.
Still referring to FIG. 2 , dipole antenna 340 can be connected for use in one or both of a transmit mode, in which signal 120 is transmitted into the surrounding earth, and a receive mode in which an electromagnetic signal such as a signal from an inground tool such as, for example, a tension monitor is received. For the transmit mode, an antenna driver section 360 is used which is electrically connected between inground digital signal processor 210 and dipole antenna 340 to drive the antenna. Again, the frequency of signal 120 will generally be sufficiently different from the frequency of the drill string signal to avoid interference therebetween. When antenna driver 360 is off, an On/Off Switcher (SW) 370 can selectively connect dipole antenna 340 to a band pass filter (BPF) 372 having a center frequency that corresponds to the center frequency of the data signal that is received from the dipole antenna. In an embodiment, a DC blocking anti-aliasing filter can be used in place of a band pass filter. BPF 372 is, in turn, connected to an analog to digital converter (ADC) 374 which is itself connected to digital signal processing section 210 . Transceiver electronics for the digital signal processing section can be readily configured in many suitable embodiments by one having ordinary skill in the art in view of the particular form or forms of modulation employed and in view of this overall disclosure. A battery 400 provides electrical power to a voltage regulator 404 . A voltage output, V out , 408 can include one or more output voltage values as needed by the various components of the electronics package. The output voltage of battery 400 can be monitored, for example, by DSP 210 using an analog to digital converter 412 . Control lines 420 and 422 from the DSP to drivers 360 and 330 , respectively, can be used, for example, to customize locating signal 120 transmit power and/or drill string transmit power that is provided to isolator 230 . The transmit power can be modified, for example, by changing the gain at which antenna driver 360 amplifies the signal that is provided from the DSP. The electronics package can be modified in any suitable manner in view of the teachings that have been brought to light herein. For example, in another embodiment, transmit power can be modified in another manner either in conjunction with gain control or independently, as will be described.
Referring to FIGS. 3 a and 3 b , an embodiment of a housing arrangement is diagrammatically illustrated and generally indicated by the reference number 440 . The housing arrangement includes a housing body 442 to which a drill head or other inground apparatus can be removably attached. By way of example, housing arrangement 440 can form part of inground tool 90 of FIG. 1 . FIG. 3 a is a diagrammatic assembled perspective view of the housing while FIG. 3 b is a diagrammatic, partially exploded view, in perspective. Housing body 442 can define fittings such as, for example, the box and pin fittings that are used by the drill rods. In an embodiment, the housing body can define a box fitting 448 at each of its opposing ends. Housing arrangement 440 comprises what is often referred to as a side load housing. A housing lid 452 is removably receivable on the housing body. The housing body defines a cavity 456 for receiving electronics package 200 . The housing body and housing lid can define a plurality of elongated slots 460 for purposes of limiting eddy currents that would otherwise attenuate the emanation of locating signal 120 ( FIGS. 1 and 2 ) from within the housing arrangement or that would otherwise attenuate reception of an aboveground signal being transmitted from portable device 20 of FIG. 1 for reception by antenna 340 ( FIG. 2 ) in the electronics package. The aboveground signal, for example, can be transmitted from a dipole antenna 470 that forms part of portable device 20 . It should be appreciated that the housing arrangement of FIGS. 3 a and 3 b comprises one example of a virtually unlimited range of embodiments of housings that are currently available, as will be further discussed immediately hereinafter.
As the result of numerous manufacturers of downhole tooling, specifically housing arrangements for supporting a given inground electronics package, there are many design configurations, each design characterized by its own manufacturing tolerances, but all of which are intended to support the interoperability of the given electronics package for use in a walk-over locating and/or homing system. The number of different housing types is still further compounded with respect to the different sizes and types of electronics packages offered in the market. Applicants recognize and have empirically demonstrated that variations in tooling design, among other factors, can significantly influence the performance of a transmitter that is part of an inground electronics package and supported by the housing. For purposes of the remainder of this disclosure, the inground electronics package may be referred to interchangeably as a transmitter.
As part of Applicants' recognitions, it has been discovered that tooling design variables including, but not limited to wall thickness, the amount of metal in proximity to the transmitter, housing slot lengths and size, each can contribute to transmitter performance. Transmitter performance in this context is considered as the amount of transmitter power consumption, which can generally be characterized as the amount of current that is drawn from a stable power source. The present disclosure, for purposes of providing a framework of descriptive nomenclature, may refer to a standard housing that can be considered as optimized for a particular transmitter. It should be appreciated that ongoing development can result in improvements to what can be considered as a standard housing. In any case, Applicants have measured transmitter power consumption in alternative or non-standard housings that is in excess of 30% more than what is considered as typical for a standard housing with the same transmitter. For example, a specific transmitter with nominal current draw of 160 mA (0.48 Watts) in a standard housing can draw an operating current of 200 mA (0.6 Watts) in a modified or different housing that is not optimized for the specific transmitter. It should be appreciated that the increase in power consumption negatively affects the battery life of the transmitter when installed in the modified housing. Battery life can be considered in this context as the operating time of a transmitter during which operating time the transmitter at least generally exhibits a stable output power or the battery supplies at least sufficient voltage to satisfy the power requirements of the power supply such as, for example, regulator 404 of FIG. 2 that provides power to the remainder of the electronics. In this regard, a longer operating time is beneficial to the end user at least for the reason that it reduces the number of times the transmitter is required to be removed from a bore to replace the batteries.
Applicants recognize that one approach for addressing increased power consumption caused by varying housing design resides in implementing a constant power transmitter configuration. A constant power configuration or design is considered to be a transmitter that does not exhibit a variable power consumption with respect to housing design. While not intending to be bound by theory, Applicants believe that variation in power consumption from one housing design to the next is attributable to the amount of signal attenuation that is caused by each housing design. Such housing-attributable signal attenuation can be thought of as a low resistance circuit that is connected in parallel to the transmitter output. The subject constant power design is accomplished, in one embodiment, by measuring the amount of power the transmitter, through the measurement of voltage and current input, is consuming after stabilization following power-up. The transmitter then adjusts transmit power to achieve a desired or target power consumption. As noted above, an acceptable power consumption, by way of non-limiting example, can be set at less than 0.5 Watts. Such a power consumption value can be established in view of a variety of different factors including those discussed below.
Attention is now directed to FIG. 4 which is a flow diagram depicting an embodiment of a method, generally indicated by the reference number 500 , that provides for constant transmitter power consumption in accordance with the present disclosure. The method begins at start 504 and includes preparation of the housing arrangement and transmitter, for example, by installing the transmitter in the housing and then installing the lid on the housing in the instance of a side load housing. In other words, the housing and transmitter are arranged in the same configuration that is to be employed during the inground operation. Operation then proceeds to 508 which initiates transmitter operation responsive, for example, to installation of batteries or through any suitable instruction to the inground electronics package to initiate transmission of locating signal 120 . It is noted that such a suitable instruction can be transmitted from the drill rig to the inground electronics package using the drill string as an electrical conductor. At 510 , once the transmission power has stabilized, the power that is being provided to antenna driver 360 can be measured. In an embodiment, wherein antenna driver 360 directly uses V out of voltage regulator 404 , power measurement, for example, can be accomplished based on the output of analog to digital converter 412 ( FIG. 2 ) that measures the output voltage of regulator 404 . The current that is supplied to the antenna is measured, for example, using a current sensing resistor 512 , having a fixed, known resistance such as, for example, 0.02 ohms. Such a low resistance provides a negligible voltage drop, however, the voltage drop accurately characterizes the current flow. A voltage V s at the sensing resistor is monitored by an ADC 514 that, in turn, is monitored by DSP 210 . The voltage across the sensing resistor can be determined as V out −V s . This voltage is divided by the known resistance of the series resistor, per Ohm's law, to obtain the current that is flowing to antenna driver 360 . Of course, the power in Watts being fed to antenna driver 360 and thereby antenna 120 at any given time can be determined through multiplication of V s by the determined current flow. With the power determination in hand, at 520 , the power consumption value is compared to a threshold power value. If the measurement-based power is less than the threshold, operation branches to 524 in which a calibration procedure can be performed to appropriately correlate signal strength to distance, for example, by measuring the signal strength at a known distance from the transmitter and determining calibration coefficients in a well-known manner. Subsequently, normal operation can be entered at 528 . If the power level is above the threshold at 520 , the transmit power is adjusted at 530 , for example, by adjusting the gain of antenna driver 360 and/or the duty cycle of its output waveform to reduce power consumption. In this regard, co-pending U.S. application Ser. No. 14/213,644, is incorporated by reference in its entirety and describes in detail the use of duty cycle for purposes of controlling transmitter output power. In an embodiment, steps 510 , 520 and 530 can operate in an iterative loop to incrementally adjust the transmit power by an appropriate step value to converge on the threshold. Once the decision at 520 is satisfied, normal operation 528 proceeds following calibration 524 .
Attention is now directed to FIG. 5 which is a flow diagram depicting an embodiment of a method, generally indicated by the reference number 600 , that provides dynamic control to implement constant transmitter power consumption during an inground operation, in accordance with the present disclosure. To the extent that method 600 shares steps with method 500 , descriptions of shared steps will not be repeated for purposes of brevity. In accordance with method 600 , however, responsive to the comparison at 520 , normal operation 528 proceeds when the current power consumption is less than the power threshold value. On the other hand, whenever the current power consumption value violates the power threshold, the transmitter power is adjusted at 530 . As part of the power adjustment step, the transmitter notifies any receiving devices such as, for example, portable device 20 of the power change. For example, the transmitter can transmit a data packet that indicates the new power level being used. The portable locator can then adjust its depth calibration automatically to reflect the different transmitter power. Accordingly, a substantially constant power draw can be maintained from the batteries throughout the duration of an inground operation.
Based on the foregoing, it should be understood that the result of the power adjustment in methods 500 and 600 can be a decrease in signal strength at a given position outside of the housing arrangement, for example, at the location of portable device 20 , in order to accomplish a sufficiently constant power consumption by the transmitter. For example, a transmitter that is configured from the factory with a nominal output of 0.48 Watts under no load (i.e., outside of a housing) can yield a targeted signal strength at 10 feet as measured by the locator 20 . This setting can be based on performance criteria in a known housing that has been deemed compatible. Therefore, any deviations from the design of the housing design will likely increase power consumption, thus requiring a reduction in signal strength to achieve the desired power consumption threshold. Particularly at job sites where there is little noise/interference, the use of a lower signal strength can be inconsequential as compared to the impact of compromising battery life that can otherwise be preserved by practicing the teachings that have been brought to light herein for purposes of maximizing battery performance.
Referring to FIG. 2 , some embodiments of electronics package 200 may utilize antenna 340 as part of a tuned circuit that is commonly referred to as an LC tank circuit. In this regard, Applicants consider that such circuits do not provide acceptable control for stable amplitude oscillation and, thereby, output power when using a tank circuit. In this regard, the amplitude can change substantially once the transmitter is installed within a drill housing, resulting in an unpredictable change in battery power consumption. For this reason, the teachings that have been brought to light above remain equally applicable.
Applicants further recognize that mechanical shock and vibration encountered during an inground operation such as, for example, a horizontal directional drilling operation (HDD), can serve as an additional variable with respect to the achievement of enhanced battery performance. For example, C-cell batteries are a commodity item, generally used in flashlights and other commodity type electronics, and are not designed to meet the high performance needs of the HDD environment. Such batteries can perform differently with respect to brand in terms of energy storage and/or shock and vibration performance. Additionally, general use batteries can exhibit a wide range of performance variation as a function of temperature. For example, cold temperatures negatively impact the energy that can be drawn from such a battery cell. This temperature-based negative influence also varies on the basis of battery chemistry; for example, Lithium-ion performs more poorly in cold temperature as compared to Nickel Metal Hydride (NiMH). Cold weather, for example, in the range from −20° C. to +8° C., is typically the temperature range that has the greatest adverse impact on battery performance at least with respect to the HDD environment. In light of the foregoing recognitions and with respect to the variables that can impact battery performance, Applicants, through extensive testing and analysis, have empirically demonstrated that general use c-cell batteries offer relatively good performance for downhole transmitters when the power consumption is less than approximately 0.5 Watts. It should be appreciated that still lower power consumption, for example on the order of 0.4 Watts, provides still further enhanced performance. While lower power consumption at these lower levels serves to increase operating time in cold temperatures with respect to general purpose batteries, Applicants have discovered that these lower power consumption levels are also of benefit when adverse mechanical shock and vibration conditions are encountered.
Based on the recognized variables of power consumption, cold weather, and mechanical shock and vibration in conjunction with the interplay between these variables, Applicants recognize that still further enhancements can be made with respect to transmitter performance. For example, the power consumption threshold can be selectable based on other criteria present in the system. With reference to FIG. 5 , if during the sensing of the transmitter power at 510 , an additional measurement is performed to measure the ambient temperature during the inground operation, for example, using temperature sensor 224 of FIG. 2 , the power consumption threshold can be configured to a different threshold that provides enhanced performance based on temperature. In this context, optimum (i.e., enhanced) performance is in relation to the battery performance in cold weather. For example, if the temperature is cold (0° C. or below), a threshold of 0.4 Watts can be selected by way of example. On the other hand, if it is warm (28° C.) then a threshold of 0.45 Watts, by way of example, can be selected. In an embodiment, the threshold(s) can be characterized as a function. For example, in one embodiment, the function can be a step function. For instance, a temperature threshold can be located at a temperature such as 8° C. such that a lower transmit power is used below this temperature and a higher transmit power is used above this temperature. In another case, the function can be represented by a polynomial such that the consumption power can be selectively or continuously adjusted for any given temperature within a particular temperature range. It should be appreciated that any suitable number of temperature thresholds can be defined that are distributed in any suitable manner.
Referring to FIG. 4 , integration of the temperature variable into the constant power transmitter process can likewise be performed by step 510 of the subject figure during startup of the transmitter by reading temperature in conjunction with making the power determination. To account for the potential for multiple power threshold values, the calibration process of step 524 can be customized. For example, if the transmitter is configured above ground at 0° C. and the power consumption threshold value is selected such that 550 counts of signal, out of a potential 1000 counts, is measured by device 20 , the power consumption threshold can be shifted dynamically, for example, as a function of discrete temperature set points. In an embodiment, device 20 can be notified of the change in the power consumption threshold such that the locator can adjust offset and scale signal strength calibration coefficients. Based on the notification, the calibration can be adjusted by using a table that is shared by the transmitter and the portable device, or via the transmitter periodically updating the current power setting as modulated on locating signal 120 such that the portable device can adjust its calibration parameters accordingly. In either scenario, a standard 10 foot calibration process remains relatively unchanged since the changes in power level (signal strength) can be extrapolated based on the consistency of the relationship between signal strength and the depth calibration coefficient.
In some embodiments, power consumption can be selectable, for example, based on forecasted mechanical shock and vibration in the bore. Such a setting can be manually entered and/or based on a measured value relatively early in the inground operation. For example, if the drilling soil is free of rocks, then it is likely that there will be little influence on battery performance with respect to shock and vibration. Mechanical shock and vibration can be detected to facilitate power consumption changes based on the drilling environment. When drilling in rock, the shock and vibration on the inground tool housing can be several hundred g's. The measurement range of typical MEMS accelerometers that are commonly used in horizontal directional drilling applications are often limited to +/−2 g, due to the need for high resolution. As a result of this limited dynamic range, such an accelerometer can constantly encounter its upper and lower limits, depending on the drilling conditions. Under adverse conditions with limited dynamic range, it is difficult to obtain a meaningful average pitch even by applying averaging to the pitch data. Accordingly, a low cost, high g, low resolution accelerometer 800 ( FIG. 2 ) can be added to the sensor suite to track the average pitch when the inground tool is rotating. In still another embodiment, a MEMS accelerometer can be used which has programmable g range such that the pitch range can be reprogrammed on-the-fly when conditions are warranted.
The foregoing description of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form or forms disclosed, and other modifications and variations may be possible in light of the above teachings wherein those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. | A transmitter is powered by a regulated battery voltage and is installable in one of a plurality of different housings, each housing is characterized by a different design and each can form part of an inground tool for performing an inground operation in which a drill string extends from a drill rig to the inground tool. An antenna driver drives an antenna based on the regulated voltage to emanate an electromagnetic signal for remote reception. A controller limits power consumption from the regulated voltage so as not to exceed a power consumption threshold, irrespective of installation of the transmitter in any one of the housings when the transmitter would otherwise exhibit a different power consumption for each housing design. A corresponding method is described. Features relating to power consumption threshold modification based on temperature as well as mechanical shock and vibration are described. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from Provisional Patent Application Ser. No. 61/852,381, filed Mar. 15, 2013.
FIELD OF THE INVENTION
[0002] The invention relates to a carrier for sports and other equipment, which can be adapted by assembly of various interchangeable equipment-specific members to a singular base member that can be carried on one's shoulders to permit convenient carrying of differing types of sports and other equipment. Specifically, the carrier of the invention comprises a base member that is assembled to a pair of shoulder straps, typically by way of a base board or backpack, so as to be carried in the manner of a backpack. Depending on the type of equipment to be carried, one of a plurality of equipment-specific members is selected and secured to the base member in a simple and efficient manner. The chosen type of equipment to be carried is then secured to the corresponding equipment-specific member.
[0003] In this way the assembly of the shoulder straps and base board or backpack and the base member can be used with various types of readily interchangeable equipment-specific members to carry various items of sports or other equipment, increasing the utility of the device.
BACKGROUND OF THE INVENTION
[0004] Various sorts of backpack-type devices are well-known, and many of these are equipped with specialized structure to adapt them to carrying specific equipment. For example, a backpack intended for mountaineering use might be equipped with a strap to receive a coil of rope, a pocket for a water bottle, straps to receive a rolled-up sleeping bag, and so forth.
[0005] The present invention differs from such backpack-type devices in that different interchangeable equipment-specific members can be assembled to a singular base member, so as to be adapted to carry different types of equipment when different activities are intended.
OBJECTS OF THE INVENTION
[0006] It is the object of the invention to provide a carrier for permitting different types of sporting and other equipment to be carried on one's back by means of a backpack-type structure, and wherein a basic assembly can be customized to carry various types of equipment by assembly of a particular interchangeable equipment-specific member thereto.
SUMMARY OF THE INVENTION
[0007] As summarized above, the equipment carrier of the invention comprises a base member that is assembled to a pair of shoulder straps, typically by way of an intermediate member, so as to be carried in the manner of a backpack. Depending on the type of equipment to be carried, one of a plurality of interchangeable equipment-specific members is selected and secured to the base member in a simple and efficient manner. The chosen type of equipment to be carried is then secured to the corresponding equipment-specific member.
[0008] More specifically, the base member may comprise a female dovetail joint, opening toward the top, and each of the equipment-specific members a corresponding male dovetail, so that the desired equipment-specific member can be assembled to the base member by simply sliding the male dovetail into the female dovetail, so that gravity retains the equipment-specific member in position, and so that the interchangeable equipment-specific members can be assembled to or removed from the base member without tools.
[0009] In a further improvement, the male dovetail may be part of an intermediate member, which allows relative rotation of the equipment-specific member though a limited range, which may be desirable for reasons of comfort.
[0010] Further aspects of the invention will become apparent as the detailed discussion thereof below proceeds.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The invention will be better understood if reference is made to the accompanying drawings, in which:
[0012] FIG. 1 shows an exploded view of the complete assembly of a first embodiment of the carrier of the invention, with an equipment-specific member intended for carrying a pair of skis;
[0013] FIG. 2 shows an exploded view of a portion of a second embodiment, wherein the equipment-specific member is adapted for carrying a snowboard, and relative rotation thereof with respect to the base member is permitted;
[0014] FIG. 3 is a partially cross-sectional view taken along the lines 3 - 3 of FIG. 2 ;
[0015] FIG. 4 is a partially cross-sectional view taken along the lines 4 - 4 of FIG. 3 , showing a variation in position of some of the components; and
[0016] FIG. 5 is a partially cross-sectional view taken along the line 5 of FIG. 3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] As above, FIG. 1 shows an exploded view of the complete assembly of a first embodiment of the carrier of the invention, in this example with an equipment-specific member intended for carrying a pair of skis. In this embodiment, a generally planar base member 10 , which is employed in all embodiments of the invention, comprises a female dovetail 12 (see FIG. 4 ) having an opening at the upper side of base member 10 , as illustrated. Base member 10 may preferably be molded of plastic, with metallic fasteners employed as described below. Base member 10 is secured to a base board 14 by screws 16 threaded into inserts 18 secured to base board 18 . Shoulder straps 20 are affixed to base board 14 by further fasteners (not shown). Shoulder straps 20 are sized and spaced, and made adjustable, so as to comfortably be worn by a person. Cross straps (not shown) connecting the shoulder straps 20 across the wearer's chest to enable further adjustment may be provided, as is well known in the art.
[0018] It is within the scope of the invention to fabricate base member 10 to be directly secured to shoulder straps 20 . However, employment of base board 14 is preferred in order to spread the load over the wearer's back. Further, base board 14 may be configured as a backpack, that is, comprising fabric members providing pockets and the like.
[0019] A first embodiment of an equipment-specific member, in this case intended for carrying a pair of skis, is shown at 22 . Equipment-specific member 22 is also generally planar and molded of plastic. Equipment-specific member 22 is shown partially cut away to show the upper end of male dovetail 24 . Male dovetail 24 cooperates with female dovetail 12 formed in base member 10 so that equipment-specific member 22 can be readily assembled to base member 10 by lifting equipment-specific member 22 above base member 10 and lowering the former with respect to the latter, as indicated by arrow A, so that the male dovetail 24 is received within the female dovetail 12 . See FIG. 4 , as this aspect of the invention is common to all embodiments.
[0020] It will be appreciated that assembly of the equipment-specific member 22 to the base board 14 by interfitting dovetails as described allows gravity to keep the equipment-specific member 22 in the position shown as least as long as the carrier of the invention is kept in the orientation shown, i.e., in the upright orientation in which it is to be worn, and moreover that the equipment-specific member 22 can be removed and replaced as desired without requiring the use of tools.
[0021] As further illustrated in FIG. 1 , in the example given the equipment-specific member 22 is intended to receive a pair of skis 26 . Skis 26 are secured to equipment-specific member 22 by a strap 28 , secured to equipment-specific member 22 at ends 28 a by fasteners 30 fitting into and secured to cooperating structure 22 a on equipment-specific member 22 . Strap 28 may be a ratcheting strap, whereby the strap is tightened over the skis 26 by operation of a ratchet handle 28 b on one end of strap 28 , cooperating with teeth 28 c on the other end of strap 28 . Such ratcheting straps are well known in the art.
[0022] To further securely confine skis 26 , one or more pairs of posts 32 , 34 may be provided. As illustrated, one pair of posts 32 may be formed integrally or otherwise fixed to equipment-specific member 22 , and a second set of posts 34 made adjustable by virtue of being secured to equipment-specific member 22 by fasteners 36 extending through transverse slots 22 b formed in equipment-specific member 22 . Posts 32 , 34 may be disposed or adjusted so as to confine skis 26 or other equipment for secure carrying.
[0023] FIGS. 2-5 illustrate a second embodiment of the invention, in which a generally planar intermediate member 40 , again molded of plastic with metallic fasteners being used where shown, is illustrated. Intermediate member 40 is interposed between the base member 10 and a different embodiment of an equipment-specific member 42 . The assembly of the base member to a back board and carrying straps may as described above in connection with the FIG. 1 embodiment, and the equipment is attached to the equipment-specific member 42 by a strap or the like fixed to the equipment-specific member at 42 f, also as described above. In this embodiment, the equipment-specific member 42 is intended to receive a snowboard.
[0024] The purpose of the intermediate member 40 is to permit the equipment-specific member 42 to be rotated through a limited range of rotation about a central pivot axis B, and secured in a desired angular position. In this way the position of the equipment to be carried can be varied as desired by the user, for reasons of comfort and convenience, e.g., so that the equipment does not tend to bump the user's legs while walking.
[0025] The intermediate member 40 is secured to the base member 10 by a male dovetail, as described above in connection with the FIG. 1 embodiment, and as shown by FIG. 4 . Intermediate member 40 is formed to define a central bore 40 a, an arcuate slot 40 b, and a central hub 40 c proud of a circular recess 40 d.
[0026] The equipment-specific member 42 is secured to the intermediate member 40 by a bolt 44 and a nut 46 . Bolt 44 thus defines the pivot axis B, about which the equipment-specific member 42 rotates with respect to intermediate member 40 . The male dovetail 24 may be formed as a separate member and secured to the intermediate member 40 by bolt 44 , as illustrated in FIG. 3 , or may be molded integrally with intermediate member 40 . The equipment-specific member 42 comprises a tubular central member 42 a, fitting around central hub 40 c, so as to assist bolt 44 in bearing the weight of the equipment-specific member 42 and any associated equipment.
[0027] The range of rotation of the equipment-specific member 42 with respect to intermediate member 40 is limited by provision of a button 50 having an enlarged head 50 b and a cylindrical shaft 50 a. Shaft 50 a rides in a bore 42 b formed in equipment-specific member 42 and extends through arcuate slot 40 d in the intermediate member, so that the range of rotation of the equipment-specific member 42 is limited by contact between the shaft 50 a and the ends of the arcuate slot 40 d.
[0028] Fixed to the end of shaft 50 a opposite head 50 b is a locator block 52 . As illustrated in FIGS. 3 and 4 , block 52 may be keyed to shaft 50 a and secured thereto by a screw. Block 52 is sized to fit within one of several recesses 40 e (see FIG. 5 ) formed in the rear side of intermediate member 40 , disposed along and extending on inner and outer radial sides of arcuate slot 40 d. A compression spring 54 is disposed around shaft 50 a of button 50 , and is confined between the head 50 b thereof and a recess 42 c formed in the equipment-specific member 42 , biasing button 50 outwardly and thereby urging block 52 against the back of the equipment-specific member 42 on either side of the arcuate slot 40 d. Accordingly, block 52 is urged into engagement with recesses 40 e, locking the equipment-specific member 42 into one of a number of relative radial positions defined by the number of recesses 40 e.
[0029] In order that the button 50 does not rotate, so that the locator block 52 remains correctly aligned with the recesses 40 a, shaft 50 a may be provided with a flat 50 c, cooperating with a flat 42 e formed in bore 42 b. See FIG. 4 . Bore 42 b and shaft 50 a could also be of corresponding non-circular cross-sectional shape, e.g., square, so as to prevent rotation. Alternatively, to avoid this small complexity, locator block 52 could be circular, and be received in partly-circular recesses 40 e, such that radial orientation of block 52 would be immaterial.
[0030] Accordingly, when the user desires to move the equipment-specific member 42 from one radial position to another, he or she simply pushes onto the head 50 b of button 50 , urging block 52 out of the recess 40 e it is then in, to the position shown in FIG. 4 , and can then rotate the equipment-specific member 42 as desired. When the block 52 reaches the desired recess 40 e the button 50 can be released and the block 52 will enter the desired recess under the urging of spring 54 , securing the equipment-specific member 42 in the new desired position.
[0031] Other features of the preferred embodiment of the invention will be apparent from the drawings. Included in these are a member 42 d formed integrally with the equipment-specific member 42 for the user to grip while adjusting the radial position thereof.
[0032] While the invention has been described in connection with the carrying of skis and snowboards, it will be apparent that many other types of elongated equipment could readily be carried by provision of suitably adapted equipment-specific members, of either the rotating type of FIGS. 2-5 or the non-rotating type of FIG. 1 . Examples of such equipment include but are not limited to rifles and other hunting gear, fishing equipment, camping equipment, hockey and lacrosse equipment, military equipment, garden tools and other items.
[0033] As noted above, for simplicity the invention has been illustrated as employing a simple base board to which the base member 10 and shoulder straps 20 are attached, but the base board could be supplanted or augmented by a backpack, providing pockets and other structure for carrying various types of cargo. Therefore, reference herein and in the attached claims to a base board should not be construed to limit the invention.
[0034] Those of skill in the art will further recognize that various alternatives are within the scope of the invention. For example, the cooperating male and female dovetails could be replaced with other cooperating structure that would enable the base member 10 to be readily attached and removed from the equipment-specific member or intermediate member, such as plural smaller parallel dovetails, “T” or paired “L”-shaped interfitting members, and the like. The respective positions of the cooperating male and female dovetails could also be reversed. In each case the preferred arrangement is one in which cooperating elongated members are provided, one defining a passageway with an upper open end and a closed lower end, and the other defining a member fitting within and retained in the passageway, such that gravity will retain the associated members in the desired position while the carrier of the invention is being worn, while permitting removal and replacement of the equipment-specific member without the use of tools.
[0035] Therefore, while several preferred embodiments of the invention have been disclosed, the invention is not to be limited thereby, but only by the following claims. | A carrier for carrying sporting equipment and other items comprises a base member that is assembled to a pair of shoulder straps, to be carried in the manner of a backpack. Depending on the type of equipment to be carried, one of a plurality of interchangeable equipment-specific members is selected and secured to the base member in a simple and efficient manner, without the use of tools. The chosen type of equipment to be carried is then secured to the corresponding equipment-specific member.
The base member may comprise a female dovetail joint, opening toward the top, and each of the equipment-specific members a corresponding male dovetail, so that the desired equipment-specific member can be assembled to the base member by simply sliding the male dovetail into the female dovetail, and gravity will retain the desired equipment-specific member in the desired position.
In a further improvement, the male dovetail may be part of an intermediate member, which allows relative rotation of the equipment-specific member though a limited range. | 0 |
This is a continuation of application Ser. No. 932,464, filed Nov. 18, 1986, now abandoned, which is a continuation of application Ser. No. 861,547, filed May 9, 1986, now abandoned, which is a continuation-in-part of application Ser. No. 555,958, filed Nov. 29, 1983, now U.S. Pat. No. 4,609,148.
TECHNICAL FIELD
This invention relates to spraying equipment and particularly, although not exclusively, to equipment for spraying herbicides.
BACKGROUND AND PRIOR ART
It is becoming increasingly common for herbicides to be applied in the form of oil-based emulsions. Such herbicides are highly efficient and very small quantities, if properly applied, can be used to treat large areas. However, to be effective, the herbicides must be applied in the form of droplets of uniform size and distribution. The nature of the herbicide, which is commonly a viscous liquid having a viscosity, for example, of 20-40 centistokes, has made it difficult for this requirement to be met.
In known proposals for promoting the creation of fine droplets of uniform size, the fluid is supplied to a rapidly rotating disc from which the fluid is ejected by centrifugal force. The face of the atomising disc over which the fluid flows is formed with radial grooves terminating in radially extending points. Examples of such proposals can be found in British patent specification Nos. 1515511 and 2008439. The radial grooves constitute channels along which fluid flows under the action of centrifugal force when the disc is rotated. At the radially outer ends of the grooves, the individual streams of fluid are ejected from the points and break up into fine droplets. When using such discs, however, it is not possible to control the spraying width or the droplet size to suit prevailing conditions.
SUMMARY OF THE INVENTION
According to the present invention there is provided a spraying device comprising a body and an atomising disc which is mounted on the body for rotation about a rotary axis. Drive means is provided for driving the disc in rotation. The atomizing disc has a fluid-receiving surface which is defined by an outer periphery of the disc from which fluid is discharged in operation. The outer periphery is polygonal as viewed parallel to the rotary axis of the disc, each side of the polygonal periphery being defined by the junction of the fluid receiving surface and a side surface which extends substantially parallel to the rotary axis, this junction being curved as viewed perpendicular to the rotary axis.
The drive means may comprise an electric motor and the equipment may further comprise an electrical lead connected to the motor and a liquid supply tube for supplying liquid to the atomising disc. The electrical lead and the supply tube may be accommodated within a support tube on which the body is mounted and emerge at the end of the support tube away from the body for connection to, respectively, a source of electrical power and a container of liquid to be sprayed.
In an embodiment in accordance with the invention, the support tube is mounted on a bracket which is adapted to be connected to a battery constituting the source of electrical power. The bracket also includes a handle so that the equipment can be carried and operated by hand. The bracket may be provided with a manually operated valve for controlling the supply of liquid to the spraying head and an on/off switch for controlling the supply of electrical power to the spraying head. The bracket may also be provided with an adjustable voltage regulator so that the voltage at the electric motor, and consequently the speed of rotation of the atomising disc, can be varied. This variability enables the spraying width of the equipment and the size of the droplets issuing from the atomising disc to be varied.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of spraying equipment;
FIG. 2 is a partly sectioned view taken along the line II--II in FIG. 1;
FIG. 3 is a partly sectioned view taken along the line III--III in FIG. 1;
FIG. 4 is a partial end view taken in the direction of the arrow IV in FIG. 3;
FIG. 5 is a perspective view of an outlet fitting for a liquid container;
FIGS. 6, 7 and 8 are perspective views of, respectively, three elements of the outlet fitting of FIG. 5;
FIG. 9 is a circuit diagram representing a voltage regulating circuit of the spraying equipment;
FIG. 10 is a side view of an atomising disc for use with the spraying head of FIG. 1;
FIG. 11 is a perspective view from the rear of the disc shown in FIG. 10;
FIG. 12 is a perspective view from the front of the disc shown in FIG. 10;
FIG. 13 is a view taken in the direction of the arrow XIII in FIG. 10;
FIG. 14 is a sectional view of the disc shown in FIGS. 10 and 11;
FIG. 15 is a view corresponding to FIG. 10 but showing an alternative form of disc;
FIG. 16 is an end view of another form of atomising disc;
FIG. 17 is a partially sectioned side view of the disc of FIG. 16;
FIG. 18 is an end view of a third form of atomising disc;
FIG. 19 is a partially sectioned side view of the disc of FIG. 18;
FIG. 20 is an end view of a fourth form of atomising disc;
FIG. 21 is a partial side view of the disc of FIG. 20; and
FIG. 22 is a sectional view of the disc of FIGS. 20 and 21.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1, the spraying equipment comprises a support tube 2 which is connected at one end to a supply assembly 4 and carries at the other end a spraying head 6. The supply assembly 4 comprises a battery carrier 8 to which a battery 10 is connected and which is provided with a hollow handle 12. The handle 12 is mounted between front and rear limbs 14 and 16 of the battery carrier 8 and is connected at its rear end to a fluid supply line 18. Near its front end, the handle 12 is provided with an on/off tap 20, and at its extreme end it is connected to the support tube 2 by a fitting 22. A supply tube 38 communicates with the interior of the handle 12 and consequently with the fluid supply line 18. As can be seen from FIG. 2, the supply tube 38 is provided at its end with a flanged connector 40. An O-ring 42 is compressed between the connector 40 and a face provided on the handle 12 under the action of the fitting 22.
The battery 10 is connected to the bracket 8 by terminal nuts 24 (only one of which is visible in FIG. 1). The two terminals are connected by a lead 26 to an adjustable voltage regulator 28 controlled by a knob 30. The output of the voltage regulator 28 is connected by a short lead 32 to an on/off switch 34. The on/off switch 34 is connected by a further lead 36 to the spraying head 6.
As will be appreciated from FIGS. 1 and 2, both the lead 36 and the supply tube 38 extend down the support tube 2. The lead 36 extends through an opening 44 in the front limb 14 of the bracket 8 and through an opening 46 in the support tube 2.
As shown in FIG. 3, the spraying head 6 comprises a body 48 which accommodates an electric motor 50 having an output spindle 52. The lead 36 is connected to the input terminals of the motor 50. The output spindle 52 of the motor carries a rotary atomiser disc 54, the spindle 52 being a friction fit within a bore 56 in the disc 54.
The body 48 has three angularly spaced passages 58. Each of these passages is inclined to the axis of the motor 50 such that it extends inwardly and towards the atomising disc 54. At the inner end of each passage 58 there is a jet 60 having a restrictor passage 62. The diameters of the restrictor passages 62 of the jets are different from one another. The restrictor passages 62 open into a cavity 64 in the end of the body 48. An annular chamber is defined between a circumferential wall of the cavity and a shank of the disc 54. The circumferential wall terminates at a lip 66 which defines, with the disc 54, an annular outlet slot 68. The slot 68 is shown greatly enlarged in FIG. 3, for the sake of clarity. The width of the slot 68 is very small compared to the corresponding dimension of the annular chamber. Thus, in the illustrated embodiment, the width of the slot 68 is very small compared with the axial dimension of the annular chamber. In practice, the disc 54 may be pushed onto the drive shaft 52 until it contacts the annular lip 66, the slot 68 then being provided as a result of axial play in the bearings of the motor 50. The width of the slot is sufficiently small to make it impossible for a stream of liquid to flow across the surface of the disc 54 without contacting the lip 66. The maximum width of the slot may, for example, be 0.1 millimeter.
The radially outer portion of each passage 58 constitutes a socket for receiving an end fitting 70 of the supply tube 38.
The end of the fluid supply line 18 away from the handle 12 is provided with a plug element 72 (FIGS. 5 and 7). The plug element 72 has a barbed connector 74 which fits into the supply line 18 and communicates with a passage 76 extending through the plug element 72. The plug element has a cylindrical portion 78 carrying an O-ring 80. There is a flange 82 at the end of the cylindrical portion nearer the connector 74.
The plug element 72 is adapted to mate with a socket element 74 (FIGS. 5 and 6). The socket element 84 would, in use, be part of a container of liquid to be dispensed by the spraying equipment. The socket element 84 comprises a cylindrical socket 86 for receiving the cylindrical portion 78 of the plug element 72. The socket 86 has an end wall 88 from which projects a hollow spigot 90 which is a close fit in the opening 76 in the plug element 72. Before first use, the through passage of the spigot 90 is closed by a breakable diaphragm 92. The interior of the spigot 90 opens into a space enclosed by an apertured skirt 94 which, in use, would be disposed within the container to which the socket element 84 is fitted. In a preferred embodiment, the container is a collapsible bag and may be supported in a rigid box, for example of cardboard, in a manner similar to that which is sometimes used for packaging wine.
Thus, to connect the supply tube 18 to the container, the diaphragm 92 is pierced and the plug element 72 is inserted into the socket 86 until the flanges 82 and 94 abut one another. To secure the plug element 72 within the socket 86, a clip element 96 (FIG. 8) is provided. This clip element has a circumferential wall 98 the ends of which subtend an angle of slightly greater than 180°. The axial edges of the circumferential wall 98 are provided with radially extending walls 100 which, when the clip element 96 is fitted to the mating plug element 72 and socket element 84, extend on opposite sides of the abutting flanges 82 and 94, as shown in FIG. 5.
FIG. 9 represents the circuitry for regulating the voltage at the motor 50. The circuitry comprises an adjustable regulator 100, a stabilizing feedback resistor 102 and a variable resistor 104, controlled by the knob 30 of FIG. 2. FIG. 9 also shows the battery 10 and the on/off switch 34. Adjustment of the variable resistor 104 alters the current input to the control terminal of the voltage regulator 100, so altering the gain between the input and the output of the voltage regulator. The stabilizing feedback resistor 102 stabilizes the output current, preventing fluctuations which might otherwise be caused, for example, by internal variations in the voltage regulator 100 or by back e.m.f.'s generated by the motor 50. The circuitry shown in FIG. 9 is capable of adjusting the output voltage between 1.25 volts and 5.4 volts, the current drain of the voltage regulator being not more than 0.003 milliamps.
In use of the equipment, the fluid supply line 18 is connected to the container in the manner described above and the bracket 18 is connected to the battery 10 by the nuts 24. The control rocker of the tap 20 is depressed to allow liquid, such as herbicide, from the container to descend under the action of gravity through the handle 12 and the supply tube 38 to the spraying head 6, where it passes through the end fitting 70 and the restrictor passage 62 into the cavity 64. The switch 34 is turned to the "on" position which causes power to be supplied from the battery 10 to the motor 50 to spin the atomiser disc 54. The liquid flows as an annular stream through the aperture 68 and is ejected by centrifugal force from the atomising disc 54 over the entire periphery of the atomiser disc. The cooperation between the disc 54 and the body 48 provides a pumping action which promotes the flow of herbicide through the jet 60. The width of the annular gap 68 is carefully selected, in dependence of the viscosity of the liquid to be sprayed, so as to ensure that an even distribution of the liquid reaches the rotary atomiser disc to achieve all-round spraying. The lip 66 provides a wiping action over the surface of the disc 54 to spread the herbicide over the disc. Thus, even though the herbicide is admitted to the cavity 64 at a single point and the disc has a relatively small diameter, even distribution can be obtained.
By controlling the voltage applied to the motor 50 by means of the voltage regulator 28, the speed of rotation of the atomiser disc 54 can be adjusted. Such adjustment will vary not only the distance over which the liquid is ejected from the disc 54, but also the size of the droplets into which the liquid is broken up as it leaves the atomising disc 54. Thus, the higher the speed of rotation, the greater the spreading width and the smaller the droplet size. In the embodiment illustrated, the speed of rotation of the atomising disc 54 is variable between approximately 200 and 4000 rpm. The disc 54 shown fitted to the output shaft 52 has a diameter of approximately 20 mm and will, at low speed, spray the liquid over a circular area having a diameter of approximately 10 cms with a large droplet size. Increasing the speed reduces the size of the droplets but will increase the diameter of the sprayed area to approximately 60 cms.
In order to achieve both a desired droplet size and a desired spreading width, the atomizing disc 54 may be replaced by alternative discs 54' and 54", illustrating in FIG. 3. The disc 54' has a diameter of approximately 30 mm and, at low speed, will spray over a circular area of approximately 30 cms diameter with large droplets and, at high speed, an area of approximately 1.2 meters diameter with small droplets. The smaller disc 54" has a diameter of approximately 10 mm and, at low speeds, will spray over an area of approximately 5 cms diameter with large droplets and an area of approximately 45 cms diameter with finer droplets, although the variation of droplet sizes at all spraying widths is likely to occur with the smaller disc.
The discs are a simple push fit on the output shaft 52 of the motor 50. However, in order to withdraw a disc from the output shaft 52 without damaging the periphery of the disc, a suitable tool may be provided for insertion into the passage 56. For example, the tool may comprise a screw threaded shank and the passage 56, at least at the end away from the output shaft 52, may be tapped to receive the shank.
The discs 54, 54' and 54" are circular as viewed axially and have peripheral edges which lie in a single transverse plane.
FIGS. 10 to 22 illustrate various alternative configurations of atomising disc which have been found to give good results.
The disc shown in FIGS. 10 to 14 has a square periphery as viewed parallel to the rotary axis of the disc (FIG. 13). This shape is achieved by cutting segments from a circular disc, and consequently the periphery of the disc is defined by four flat surfaces 126 (FIG. 10). Each surface 126 has the shape of a crescent, tapering to points 110 at the corners of the disc. Alternatively, as shown in FIG. 15, the surfaces 126 could meet each other at common edges 138 which extend parallel to the rotary axis of the disc. In operation, the liquid flows as a film over the surface 127 of the disc which receives the fluid to be sprayed, and then flows from the surface 127 to the surfaces 126 at a position midway along each surface 126 (i.e. at the radially innermost part of the periphery). The fluid then migrates to the corners of the disc over the surfaces 126. The liquid is then thrown off as droplets from the points 110 or edges 138 at which the surfaces 126 meet each other. Because the inner surface 127 (i.e. that surface over which liquid flow during use of the disc) is concave, the peripheral edge 112 of the surface 127 does not lie in a single transverse plane. Instead the periphery 112 of the disc at the corners of the square is further from a notional plane 128 passing through the end face 129 of the atomising disc than are points on the periphery 112 of the disc midway between the corners. In other words, as shown in FIG. 10, the dimension d 1 is greater than the dimension d 2 . The length of each side of the square may be 12 mm. Good results are achieved if the diameter of the lip 66 is also approximately 12 mm.
The disc shown in FIGS. 16 and 17 is generally circular, as viewed parallel to the rotary axis (FIG. 16), but is provided with serrations or teeth 130. The tips of the teeth 130 are further from a plane passing through the end face of the disc than are the roots of the teeth, and so again, different portions of the periphery of the disc are at different positions along the axis of the disc.
The outer diameter of the disc is 34 mm, the height of each tooth being 2.5 mm. The angular pitch of the teeth is approximately 8°, giving 45 teeth in all. The teeth may be raked in either direction, but preferably, if they are raked, they slope towards the rear, with respect to the intended direction of rotation of the disc in operation. In operation, the teeth 130 cause air to be drawn between them as the disc rotates. The flow of air promotes the formation of fine droplets of consistent size.
The disc shown in FIGS. 18 and 19 is similar to that of FIGS. 16 and 17 in that it is provided with teeth 132, but is more suitable for discs of smaller diameter, such as 10 mm. In the disc of FIGS. 18 and 19, the teeth 32 have arcuate, rather than pointed, tips separated from each other by radial notches 133.
In the embodiment of FIGS. 20 to 22, the periphery, as viewed along the axis of the disc, is again generally square, although somewhat barrelled. This configuration is achieved by bending segments of a circular disc into a more axial position, and again has the effect of positioning different portions of the periphery at different positions along the axis of the disc. The bent-back portions 134 are provided, both inside and outside, with grooves 136 which lie in planes perpendicular to the axis of the disc.
The discs illustrated in FIGS. 10 to 22 result, in operation, in fine liquid droplets of consistent size. It is believed that this effect is achieved because the shapes of the discs create turbulence in their vicinity which causes liquid being discharged from them to collide with parts of the rapidly rotating disc and so to be broken into fine droplets.
Adjustment of the flow rate of liquid to the cavity 64 and thus from the disc 54 may be achieved by inserting the fitting 70 into the appropriate socket 58, since the flow rate will be controlled by the diameter of the restrictor passage 62 in the jet 60. These passages may, for example, range from 0.75 mm to 2 mm.
The spraying equipment described with reference to the drawings provides simple adjustment of spraying width and droplet size to meet the requirements of different circumstances. For example, in windy conditions, it is desirable to have a large droplet size in order to avoid wind drift.
The use of the connector described with reference to FIGS. 5 to 8 provides a convenient method of connecting the spraying equipment to containers of ready-to-use weed killing chemicals, i.e. chemicals which require no mixing by the operator. The connector enables the spraying equipment to be "plugged in" directly to the container in which the chemical is supplied, thus avoiding any handling of the chemical by the operator.
Although the present invention has been described with reference to the spraying of herbicides, it is also suitable for other spraying operations, such as the spraying of lubricants or coating compositions such as varnish. | Equipment for spraying a fluid such as a herbicide comprises a support tube on which is mounted a head comprising a body and a rotatable disc. Electrical supply leads and a supply hose for fluid pass to the head through the support tube. The head and the body define between them a narrow annular gap. Fluid is supplied to the disc at a position radially inwards of the gap and flows through the gap to be discharged as fine droplets from the periphery of the disc. The width of the gap is such that the fluid passing through it is wiped circumferentially so that it is distributed around the disc. This promotes an even spray of fluid from all parts of the periphery of the disc. Special shapes for the disc are proposed in order to promote the formation of small droplets of uniform size. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an apparatus and method for directing steam into a subterranean formation penetrated by a well. More particularly, the invention relates to an apparatus and method to receive steam injected down the well via a conduit and direct the steam against and into a selected section of a subterranean formation.
2. Description of the Prior Art
Steam injection is a well known method for stimulating the recovery of hydrocarbons from subterranean formations penentrated by a well. The method is especially applicable to recovery of highly viscous hydrocarbons having a high resistance to flow under normal subterranean conditions of temperature and pressure, but whose viscosity can be reduced and flow rate increased by the application of heat thereto. In the steam injection process as commonly practiced, steam is generated at the surface of the ground and injected down the well via an open-bottom-ended conduit. The steam exits the bottom of the conduit and enters the formation at the most permeable point along the well sidewall, wherever this most permeable point may be located. Thus, there is limited selectivity in the injection process. A packer cannot be used below the conduit to confine the steam to a limited area because during the steaming operation some formation particles slough into the hole and build up on top of the packer. Thus, the packer easily becomes stuck in the hole and cannot be readily removed following the steaming operation.
In the formation treating operations, it is often desired to inject steam into a particular stratum of the formation, which may or may not be the most permeable portion thereof. Additionally, it may be desired to inject steam first into one particular stratum of a formation for some time and then into another stratum of the formation. This is true where the formation is made up of alternate horizontal layers of an oil-containing strata and a shale strata. In using the open-bottom-ended conduit of the prior art, it was difficult to inject steam into anything other than the most permeable strata. Even when the position of the conduit is changed to be adjacent a second strata into which it was desired to inject steam, the steam still tended to go primarily into the most permeable strata which was previously treated.
Accordingly, a principal object of this invention is to provide an apparatus and method for injecting steam into selected strata of a subterranean formation.
Another object of the invention is to provide such an apparatus and method for successively steaming a plurality of oil-containing strata separated by shale strata.
Still another object of the invention is to provide such an apparatus and method which inject steam into such a formation with a minimum of erosion of the formation.
A further object of the invention is to provide such an apparatus which attaches to the bottom of the tubing and whose vertical position in the well can be changed between steam cycles by raising or lowering the tubing.
A still further object of the invention is to provide such an apparatus and method capable of injecting steam into a desired stratum of the formation without the aid of packers.
Other objects, advantages and features of the invention will be apparent from the following description.
SUMMARY OF THE INVENTION
Briefly, the invention involves an apparatus and method for improving the production of oil from relatively thick subterranean formations containing viscous hydrocarbons and penetrated by a well by the injection of steam into selected strata of the formation. The steam injecting apparatus is made up of an elongated hollow housing sized to be passed through a well, a coupling attaching the upper end of the housing to the lower end of the well tubing, a plug in the lower end of the housing, a plurality of apertures spaced apart circumferentially at regular intervals around and extending through the sidewall of the housing, jet nozzles extending outwardly and downwardly from each aperture, and, optionally, means to reduce the amount of steam which would otherwise rise into the tubing-casing annulus. The apparatus is attached to the bottom end of the well tubing and run into the well opposite the base of the strata which is to be treated with steam. Steam is generated at the surface, passes down the well tubing, into the elongated hollow housing, out through the jet nozzles, following which it impinges against and enters the formation at this point.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more readily understood by reference to the accompanying drawings, in which:
FIG. 1 is a vertical view, partially in cross-section, through a subterranean earth formation schematically illustrating a well equipped with the apparatus of this invention which is positioned opposite a formation into which steam is being injected;
FIG. 2 is an elevation view, partially in cross-section, showing in detail the steam injection apparatus; and
FIG. 3 is a horizontal cross-sectional view of the apparatus illustrated in FIG. 2 taken along the line 3--3 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1, well 2 is drilled through overburden 4 lying beneath surface 6 and extends through first oil-bearing formation 8. Well 2 contains casing 10 which is cemented in place through overburden 4 and part way into first oil-bearing formation 8 with cement sheath 12. Casing 10 is provided with conventional well head assembly 14 which forms a closure at the surface end of casing 10. Casing 10 contains tubing conduit 16 the upper end of which extends through well head assembly 14 and the lower end of which terminates in the open hole below casing 10 and opposite first oil-bearing formation 8. The open hose below casing 10 contains perforated liner 18 which extends over first oil-bearing formation 8, underlying shale strata 20 and second oil-bearing formation 22. The annular space between perforated liner 18 and sidewall 24 of well 2 is filled with gravel 26. Steam is generated by conventional steam generating apparatus 28 positioned at surface 6 near well 2 and is injected into tubing 16 via flow line 30. Steam passes down tubing 16 and into steam injecting apparatus 32 which is attached to the lower end of tubing 16 by coupling 34. Double swab cups 36 attached to the upper portion of steam injecting apparatus 32 prevent steam from rising into the annular space surrounding tubing 17 above steam injecting apparatus 32.
Referring now particularly to FIG. 2 and FIG. 3 as well as FIG. 1, steam injection apparatus 32 includes housing, chamber, pipe section or nipple 38 which is generally of about the same diameter as tubing 16 to which is is attached by coupling 34. The lower end of housing 38 is closed as by bull plug 40 or any convenient plugging means to close off the otherwise open lower end of housing 38. The sidewall of housing 38 contains a plurality of spaced apart ports or apertures 42 through which jet nozzles or tubes 44 extend outwardly from housing 38 and downwardly towards the sidewall of well 2. Steam passing into steam injection apparatus 32 from tubing 16 is forced out through jets 44 and directed against and into first oil-bearing formation 8. Thus, there is formed in formation 8 a relatively uniform cylindrical steam-containing area 46. Area 46 surrounds well 2 and is opposite steam injecting apparatus 32. The hydrocarbons contained in area 48 are heated by the steam, substantially reduced in viscosity, and rendered more susceptible to removal from area 46 in oil recovery operations carried out in conjunction with or subsequent to the steam injection process.
Elongated hollow housing 38 of steam injecting apparatus 32 is removably attached to the lower end of tubing 16 and receives the steam injected down tubing 16. Housing 38 can be of any convenient shape as long as it can be lowered through casing 10. It is generally cylindrical in shape for convenience in attaching to tubing 16. A 6-foot-long housing can be conveniently used in many steaming operations. Housing 38 is attached to tubing 16 by threaded coupling 34 or any similar attaching means. Plug or stopper 40 closes the bottom end of housing 38 so that steam cannot escape out the bottom end. Plug 40 can conveniently be a threaded bull plug or similar closure means threaded onto or into the bottom end of housing 38. Ports or outlets 42 in the sidewall of housing 38 are apertures drilled or machined in the said sidewall through which steam entering housing 38 escapes. Apertures 42 are spaced around the sidewall of housing 38, preferably at regular intervals so that steam is uniformly injected from housing 38 and against surrounding formation 8. One convenient arrangement of apertures 42 is in horizontal rows, each aperture 42 being spaced 90° from the nearest other apertures 42 and with the rows being about one foot apart. Each aperture 42 is provided with a jet nozzle or tube 44. Jet nozzles 44 are affixed in or around apertures 42 as by welding or being screwed in. Jet nozzles 44 are either hollow tubes originally or are solid rods through which a hole is drilled after being affixed in or around apertures 42. A preferred structure is provided by first welding hollow tube jet nozzles 44 onto housing 38 and then milling a hole through housing 38 as by inserting a milling tool up through hollow tube jet nozzles 44. This provides a smooth opening through which steam can flow. If jet nozzles 44 are screwed into apertures 42, car should be exercised that jet nozzles 44 do not extend inside housing 38 as such an arrangement tends to slow down the flow of steam out of housing 38. The openings through jet nozzles 44 are sized so that steam from housing 38 escapes therethrough at a force sufficient to impinge against and penetrate formation 8. It is found that if steam is passed laterally through apertures 34 straight out against formation 8 with or without jet nozzles 44 being present, the steam impinges upon formation 8 with a force sufficient to severely erode formation 8. Better penetration of steam with a minimum of erosion is achieved by positioning jet nozzles 44 so that the steam inpinges against formation at an angle of from 20° to 40° from the axis of the well, preferably about 30°. By pointing jet nozzles 44 downwardly, the natural tendency of steam to rise in the annulus between well 2 and steam-injecting apparatus 22 is at least partially offset.
Apertures 42 and jet nozzles 44 should be of sufficient number and arrayed around steam injection apparatus 32 in such a manner that steam passing therethrough contacts the entire vertical extend of formation 8 opposite steam-injecting apparatus 32 in a substantially uniform manner. This forces steam into formation 8 for a substantial depth regardless of any permeability variations that might exist over this vertical extent. Jet nozzles 44 are sufficiently long to direct the steam at the proper angle, but not so long as to provide an obstruction to the passage of steam-injecting apparatus 32 into and out of well 2.
After completion of a first steaming operation in first oil-bearing formation 8, steam injecting apparatus 32 can be lowered to a position near the base of second oil-bearing formation 22 and a second steaming operation carried out. In this second steaming operation, the unique steam injection apparatus 32 will force steam primarily into second oil-bearing formation 22 rather than into first oil-bearing formation 8 even though the latter formation is the more permeable zone.
It is helpful in some instances to begin a steam injection process by injecting into flow line 30 for a short period of time, said 12 hours, low quality steam, e.g., steam containing about 50 percent by weight to about 70 percent by weight steam and the remainder water. The steam quality is measured as it exits steam generator 28. This low quality steam contains a substantial amount of hot water and serves to flush and clean out flow line 30 which may contain formation particles deposited during previous operations of well 2. If high quality steam is injected into flow line 30 which is dirty, the steam tends to entrain the formation particles, carry them downhole and impinge them against liner 18 at such a high velocity that liner 18 may be damaged. If flow line 30 is first cleaned with low quality steam, less damage to liner 18 occurs.
For the remainder of the steaming operation it is preferred to employ high quality steam, i.e., that containing more than about 70 percent by weight and most preferably at least about 80 percent by weight steam.
The steam injecting apparatus of this invention is further demonstrated by the following example which is presented by way of illustration, and is not intended as limiting the spirit and scope of the invention as defined by the appended claims.
EXAMPLE
A well has a producing zone extending from 1,290 feet to 1,480 feet. The well is given two conventional steam treatments with oil production between treatments. The well is then given a third conventional steam treatment wherein 4,100 MM B.T.Us. of steam are injected out of the open-bottom-ended tubing positioned at 1,250 feet for a period of 10 days. A radioactive tracer is added to the last portion of the steam. A log of the formation following the steam treatment indicates that the steam enters the formation from 1,280 feet to 1,390 feet. Thus, the lower portion of the producing zone receives no steam. The well is produced for 8 months. The well is then given a steam treatment using the apparatus of this invention. A 6-foot long, 2-inch diameter steaming nipple having four 0.5 inch inside diameter 0.75 inch long jets per foot is attached to the bottom end of the tubing and suspended in the well at a depth of 1,420 feet. The jets are circumferentially arranged around the nipple in a uniformly spaced manner and point downwardly at an angle of 30° from the vertical. The lower end of the nipple is closed with a bull plug. Steam injected down the tubing, through the steaming nipple and into the formation totals 3,500 MM B.T. Us. during a period of 10 days. A radioactive tracer is added to the last portion of the steam. A log of the formation following the steam treatment indicates that the steam enters the formation from 1,375 feet to 1,455 feet. The well is produced for 8 months during which time 2,000 barrels more oil is recovered than during the 8 months following the last conventional steaming operation. Thus, the use of the steaming nipple results in steam entering the lower portion of the formation and more oil being recovered even though less steam was used than in the previous conventional steam treatment.
While in particular embodiments of the invention have been described, it will be understood, of course, that the invention is not limited thereto since many modifications can be made and it is intended to include within the invention such modifications as are within the scope of the claims. | An apparatus and method for directing steam into selected strata of a relatively thick subterranean formation penetrated by a well. The apparatus includes an elongated housing attachable to the lower end of the well tubing, the housing having a closed lower end and a plurality of jets spaced around the sidewall thereof so as to be positioned opposite the strata to be treated. The jets direct the steam outwardly and downwardly against the formation face, causing it to preferentially enter the selected strata. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the field of process rolls, more particularly it pertains to heat transfer rolls for use in the production and processing of sheets of material, such as paper, plastic and rubber.
2. Description of the Prior Art
The principal techniques for manufacturing wide sheets of polymer, such as plastic, or of paper are an extrusion process and a cast film process. The flat sheet extrusion process is used to produce plastic sheet by pressing molten polymer material between two or more rolls that serve to flatten the material into a continuous sheet having a desired thickness. The material passes around and between multiple rolls during production and processing of the sheet. Often a pull roll is used to keep tension in the extruded flat sheet as it exits the final roll. The sheet is then continuously rolled on a core, or it is cut and stacked in flat sheets.
U.S. Pat. No. 5,567,448 describes a heat transfer roll for use in forming flat sheet material by an extrusion process. The roll includes a core, a shell surrounding the core and a duct, through which fluid for controlling the temperature of the sheet flows from the core to the shell. The roll extrudes sheet having a uniform thickness across its width and provides one cooling fluid flow passageway. The roll has no provision for multiple fluid channels and cannot accommodate variable sheet thickness or a variable heat content of sheet material across the width.
Various techniques have been employed to control the temperature on the surface of a roll used to form sheets of paper or plastic. For example, U.S. Pat. No. 4,233,011 describes a roll having a cylindrical core, a tubular shell surrounding the core, and a heating strip carried on the core. Temperature sensors located on the core are used to produce a signal employed by an electrical regulating circuit that controls the application of electric power supplied to the heating strip. The heating strip is regulated so that a predetermined temperature difference between the heated and unheated sides of the core is maintained. The purpose of maintaining this temperature difference on the core is to produce thermal displacement or arching of the core. That displacement is transmitted to the shell. U.S. Pat. No. 5,103,542 describes a fluid distribution system for a variable-crown roll that includes a stationary central axis and a revolving shell surrounding the axis. The fluid distribution system includes a system of ducts in which pressurized fluid enters isolated areas on the roll. The fluid distribution system includes axial ducts and transverse bores that direct fluid to hydraulic loading elements to compensate for stresses resulting during processing. Neither of these patent references describes the use of multiple temperature channels on a forming roll.
Rolls for forming sheet material have conventionally included an annular passage located between a core and a shell surrounding the core. Fluid for cooling the sheet material flows in the annular passage along a spiral path bounded by partition strips that extend radially between the core and the inner surface of the outer shell. U.S. Pat. Nos. 3,548,929 and 3,676,910 describe rolls having a spiral fluid flow channel. The '910 patent describes a machine for forming T-shaped fins that include a sealing gasket, the fins being used as a spiral seal between the core and outer shell of a fluid heat exchanger type roll. The '929 patent describes use of a continuous partition strip arranged in a spiral and located in an annular space between the core and outer shell of the roll. The partition strip is formed of a composite structure that can withstand the chemical and thermal action of certain fluids used for heat transfer purposes that tend to corrode or decompose partitions made of rubber and plastic.
The process for producing long, wide, thin sheet material of plastic, paper and similar materials by the cast film processing includes use of an extruder that delivers molten material in a fluid state to a die. The die has a profiled opening or orifice that forms the surface contour of the sheet as the molten polymer passes through the die orifice to form an elongated sheet width. The sheet may have relatively thick areas spaced across the elongated width and extending continuously along the length of the sheet.
Accordingly, the rate of cooling of the cast sheet product varies across the sheet, that rate being longer in the areas of thick sheet and shorter in the areas of thin sheet. There is need for a heat transfer roll that accommodates the cooling requirement differences across the sheet width by providing multiple cooling channels located within the roll and located appropriately to correspond to the location of thick and thin sheet areas.
SUMMARY OF THE INVENTION
In one of its embodiments, the present invention provides a heat transfer roll on which molten sheet material is cooled, the roll including a first cylindrical shell; a second cylindrical shell surrounding the first shell, and defining a cylindrical annular space therebetween, said space having an axial length and a periphery; a first flow channel located in said space, extending along a first portion of the axial length and around the periphery of said space, having a first inlet and a first outlet; and a second flow channel located in said space, extending along a second portion of the axial length and around the periphery of said space, having a second inlet and a second outlet.
In another of its embodiments this invention contemplates a method for forming a long sheet of material having a cross-section with a width and a thickness, the thickness having a relatively thin area and a relatively thick area, the thin area extending across a first portion of the width, and the thick area extending across a second portion of the width, or vice versa. The method comprising the steps of passing molten material through a die having an orifice with a shape complementary to the cross-section of sheet being produced; placing said passed sheet on a roll having a surface exposed to a first flow channel and a second flow channel; locating the sheet on the roll such that the lateral location of the thin area corresponds to the lateral location of the first flow channel, and such that the lateral location of the thick area corresponds to the lateral location of the second flow channel; supplying fluid from a first fluid source to the first flow channel; and supplying fluid from a second fluid source to the second flow channel.
As previously described, a molten sheet having varied thickness cross-sectional profiles will have different solidification times at the thinner and thicker portions of the sheet. As a result, cooling of the molten material at one rate causes degradation and varied shrinkage as portions solidified across the profile as different times. By increasing the cooling rate of the thicker profiles so that it substantially matches the time of solidification of the thinner profiles, the quality of the product is improved. Therefore, a multiple thermal channel roll according to the present invention allows a wider operating range of thicker verses thinner sheet profiles due to the wider cooling ranges between the thermal channels.
Further, because thicker portions of the molten sheet material can be cooled faster by appropriate choice of coolant and other process variables, a roll having multiple coolant temperature channels according to the present invention permits the process line speed to be increased compared to the speed using a conventional forming roll.
It is still another advantage of this invention that different cooling fluids can be used in each fluid flow channel to maximize the heat transfer from the sheet material to the coolant in the several cooling channels on the roll. It is yet another advantage that both heating and cooling channels can be used when producing sheet material of composite materials having substantially different thermal properties.
BRIEF DESCRIPTION OF THE DRAWINGS
It is to be understood that the drawings are designed for the purpose of illustration only and not as a definition of the limits of the instant invention, for which reference should be made to the claims appended hereto. Other features, objects and advantages of this invention will become clear from the following more detailed description made with reference to the drawings in which:
FIG. 1 is a diagram representing process steps for producing thin sheet by the cast film process employing a roll having multiple thermal channels according to the present invention;
FIG. 2 a front elevation view taken at plane 2 — 2 of FIG. 1 showing a non-uniform cross-sectional contour profile on a sheet leaving a die;
FIG. 3 is a side elevation view taken at plane 3 — 3 of FIG. 1 ;
FIG. 4 is a cross section taken through a central longitudinal axis of a process roll according to the present invention; and
FIG. 5 is a view looking radially inward toward the inner shell with the outer shell removed and the cylindrical surface of the outer shell projected into a horizontal plane.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning first to FIG. 1 , 2 and 3 , the process equipment and machinery for producing long, wide, thin sheet material of plastic, paper and similar materials by cast film processing includes an extruder, shown generally at 10 , which receives stock, such as polymer through a bin 12 . The extruder delivers molten material in a fluid state through a conduit 14 to a die 16 . The die has a profiled orifice 18 that forms the surface contour and cross-sectional profile of the sheet as the molten polymer passes through the die orifice. The shape of the die orifice 18 is the complement of the surface contour and cross-sectional profile of the sheet being produced. The sheet may have relatively thick areas 20 , shown in FIG. 2 in the form of projections, spaced mutually across the width and extending continuously along the length of the sheet, the projections being separated by thin, flat areas 21 , which also extend continuously along the length of the sheet.
The sheet material leaves the die 16 and passes over a heat transfer roll 30 , supported for rotation at each axial end on journals 32 , 34 . An air knife may be used to force the sheet closely against the heat transfer roll 30 . The sheet is cooled on the outer surface of roll 30 and cut into lengths by a secondary process before final assembly or subsequent processing.
FIG. 4 illustrates the roll 30 , according to the present invention, for use in forming sheet material having thicknesses, heat content properties, and cooling rate requirements that vary across the width of the sheet. The roll includes left-hand and right-hand journals, 32 , 34 , which are formed in a known manner to be received in conventional bearings or pillow blocks, on which the roll is supported for rotation about a central axis 36 . Preferably each journal 32 , 34 includes a keyway 38 , through which power is transmitted from an external source to rotate the roll about axis 36 . At the right-hand end of the roll, a circular end plate 40 is secured to the right-hand journal 34 by a welded connection 42 . At the left-hand side of the roll, another circular end plate 44 is secured by a circular weld 46 to the outer surface of the left-hand journal 32 .
Located within the right-hand journal 34 , at the fluid inlet side of the roll 30 , is a siphon tube 48 , which is connected through a rotary union 50 to a first source conduit 52 , which is hydraulically connected to a first source of fluid liquid 54 , i.e., chilled or heated fluid. Surrounding the siphon tube 48 and located in an annular passageway between the outer wall of the right-hand journal 34 and the wall of siphon tube 48 is a fluid journal-passage 56 , which is similarly connected through the rotary union 50 to a second source conduit 58 connected to a second fluid source 60 holding heat transfer fluid or liquid.
Located within the left-hand journal 32 , at the fluid outlet side of the roll 30 , is a siphon tube 62 , which is hydraulically connected through a rotary union 64 to a conduit 66 , through which fluid is returned to the first fluid source 54 . Surrounding the siphon tube 62 and located in an annular passageway between the outer wall of journal 32 and the wall of siphon tube 62 is a fluid journal-passage 68 , which is similarly connected through the rotary union 64 to a conduit 70 , through which fluid is returned to the second fluid source 60 .
A first siphon plug 72 forms a bulkhead that blocks and closes the end of the fluid journal-passage 56 in the right-hand journal 34 . Similarly, a second siphon plug 74 closes the end of the fluid journal-passage 68 in the left-hand journal 32 .
A first tube 76 is fixed by a weld 78 to the inner end of the right-hand journal 34 , and a second tube 80 is fixed by a weld 82 to the inner end of said left-hand journal 32 . The ends of tubes 76 , 80 are mutually connected by a center weld 84 . The siphon tube 48 is hydraulically connected to the tube 76 , which is blocked by a third siphon plug 86 , but tube 76 is blocked by the first siphon plug 72 from communication with the annular journal-passage 56 . The tube 80 is in direct fluid communication with the siphon tube passage 62 , but tube 80 is blocked by the second siphon plug 74 from communication with annular journal-passage 68 .
Extending radially outward from the axis 36 and fixed to the right-hand journal 34 is a first riser pipe 88 , which is in fluid communication with annular journal-passage 56 . Similarly, a second riser pipe 90 is fixed to said left-hand journal 32 and extends radially outward from axis 36 . The second riser pipe 90 is in fluid communication with the annular journal-passage 68 .
Located at the radially outer end of the riser pipes 88 , 90 is an inner shell 92 providing a circular cylindrical outer surface 94 . The inner shell 92 is sealed and joined by a weld 96 to end plate 40 , and inner shell 92 is sealed and joined to end plate 44 by a weld 98 .
Spaced radially from the cylindrical surface 94 of the inner shell 92 is an outer shell 100 , which has an outer circular cylindrical surface 102 , joined and sealed at the inlet and outlet sides of the roll to the end plates 40 , 44 by welds 104 , 106 . Located within the cylindrical annular space 107 between the inner shell 92 and outer shell 100 are spiral-shaped seals 108 .
Located approximately midway between the riser pipes 88 , 90 is a diverter 110 in a form of tube communicating with a spiral channel having portions 112 , 114 located at opposite axial sides of the diverter 110 . Communication between the spiral portions 112 , 114 is blocked by circular seals 116 , 118 , which extend around the circumference of the inner shell 92 . The diverter pipe 110 is fixed to the inner shell 92 and is supported on the shell by a hanger flange 120 .
An annular channel portion 130 located between seals 116 , 118 is hydraulically connected and supplied with fluid from the first fluid source 54 through the first tube 76 and a third riser pipe 132 . The annular channel portion 130 is hydraulically connected also to the second tube 80 by a fourth riser pipe 134 .
In this way, the roll 30 contains first and second flow channels, each channel hydraulically connected to one of the fluid sources 54 , 60 . The first flow channel for carrying coolant from the inlet side to the outlet side of roll 30 is supplied from the second fluid source 60 , through conduit 58 , rotary union 50 , journal-passage 56 , and first riser pipe 88 to the spiral channel portion 112 located in annular space 107 , between inner shell 92 and outer shell 100 . Diverter 110 carries fluid around the annular channel portion 130 , bounded by circular seals 116 and 118 , to the spiral channel portion 114 . The second riser pipe 90 carries fluid from spiral portion 114 to the journal-passage 68 located between the inner wall of the left-hand journal 32 and the outer wall of siphon tube 62 , through rotary union 64 , and conduit 70 for return to fluid source 60 .
The second fluid flow channel for carrying coolant from the inlet side to the outlet side of roll 30 is supplied from the first fluid source 54 , through conduit 52 , rotary union 50 , siphon tube 48 , tube 76 , and the third riser pipe 132 to the annular channel portion 130 located in the annular-space 107 between the circular seals 116 , 118 . The fourth riser pipe 134 carries hydraulic fluid from the annular channel portion 130 , through tube 80 , siphon tube 62 , rotary union 64 , and conduit 66 for return to fluid source 54 .
In this embodiment, the roll defines a first outer cooling channel having a first spiral portion 112 that extends longitudinally on the outer cylindrical surface 102 of the outer shell 100 between end plate 40 and seal 116 , and having a second spiral portion 114 located on the outer cylindrical surface 102 of outer shell 100 and extending longitudinally between circular seal 118 and the end plate 44 . The roll also includes an annular cooling channel portion 130 in its center, located on the outer circular surface 102 of outer shell 100 extending longitudinally between circular seals 116 and 118 .
The radially outer end of the first riser pipe 88 communicates with the spiral portion 112 of the first flow channel through an inlet 146 , through which fluid enters the spiral portion 112 of the first flow channel. The radially outer end of the second riser pipe 90 communicates with the spiral portion 114 of the first flow channel through an outlet 148 , through which fluid exits the spiral portion 114 of the first flow channel. Fluid flow continuity between the spiral portions 112 , 114 is provided by the diverter 110 , which has an inlet 122 through which fluid exits spiral portion 112 and enters diverter 110 , and an outlet 124 through which fluid leaves diverter 110 and enters spiral portion 114 .
Similarly, the radially outer end of the third riser pipe 132 communicates with the second flow channel, being the cylindrically annular channel portion 130 , via an inlet 150 , through which fluid enters the annular channel portion 130 . The radially outer end of the fourth riser pipe 134 also communicates with the annular channel portion 130 of the second flow channel via an outlet 152 , through which fluid exits the annular channel portion 130 and enters riser pipe 134 . Fluid flow continuity between riser pipes 132 and 134 is provided by channel portion 130 .
FIG. 5 shows an embodiment of a multi-channel arrangement with spiral seal 108 and circular seals 116 , 118 , viewed radially inward with outer shell 100 removed and the cylindrical outer surface of the inner shell 92 of the roll 30 in a horizontal plane. The spiral channel portion 112 of the first flow channel extends longitudinally along axis 36 from the inner surface of end plate 40 to seal 116 . Spiral portion 112 , which is located in the annular space between the outer shell 100 and inner shell 92 , entirely encircle the inner shell 92 several times. FIG. 5 shows spiral portion 112 extending four times around the circumference of the roll 30 .
Spiral seal 108 abuts end plate 40 and travels angularly about and axially along the outer surface of inner shell 92 in a spiral path. The radially outer end of seal 108 contacts the inner surface of the outer shell 100 , thereby sealing the outer surface of inner shell 92 and the inner surface of outer shell 100 against fluid flow across seal 108 , and directing flow along the length of seal 108 . Therefore, fluid entering channel portion 112 from inlet 146 flows along a spiral path bounded by shells 92 , 100 and seal 108 , to inlet 122 , where the fluid enters diverter 100 . Fluid in the first flow channel then leaves diverter 100 through outlet 124 , enters the spiral channel portion 114 , and flows along channel portion 114 to the outlet 148 . Fluid in the first flow channel would then leave the roll through the second riser pipe 90 and journal-passage 68 , rotary union 60 and conduit 70 .
Preferably, but not always, the axial pitch of the spiral about the axis 36 in the spiral portion 112 decreases angularly from the inlet 146 as the seal 108 extends away from end plate 40 toward circular seal 116 . After then passing through diverter 110 , fluid enters the spiral portion 114 . Similarly, as seal 108 moves away from the circular seal 118 , in the spiral portion 114 , the axial pitch of the spiral gets smaller and the width of the channel increases, so that resonance time of the fluid passing therethrough increases. In this way, the resonance time of the cooling fluid increases as the fluid moves through channel portions 112 , 114 from inlet 146 to outlet 148 , so as to maintain uniform cooling of the sheet across its width.
Circular seals 116 , 118 are supported on the outer surface of inner shell 92 and travel along the circumference of the outer surface of inner shell 92 in a circular path. The radially outer end of seals 116 , 118 contact the inner surface of the outer shell 100 , thereby sealing those surfaces of the shells against fluid flow across seals 116 , 118 , and directing flow in the annular channel portion 130 along the length of those seals.
In the vicinity of the diverter inlet 122 and outlet 124 , the inlet 150 of the third riser pipe 132 and outlet 152 of the fourth riser pipe 134 are sealed mutually by transverse seal 156 . In this way, fluid entering the annular flow channel portion 130 through the inlet 150 from riser pipe 132 flows about axis 36 and along the annular space bounded by seals 116 , 118 , the outer surface of inner shell 92 and the inner surface of outer shell 100 , to the outlet 152 at riser pipe 134 . Then fluid in this second fluid flow channel enters tube 80 and exits the roll through the siphon tube 62 in the journal 32 , rotary union 64 and conduit 66 .
Continuing to focus in the vicinity of the diverter inlet 122 and outlet 124 , seal 108 either continues uninterrupted past seals 116 , 118 , or seals 116 , 118 continue uninterrupted past seal 108 . In either case, transverse seal 156 prevents direct communication between the inlet 150 and outlet 152 of riser pipes 132 , 134 , and seal 108 continues its spiral path angularly about and axially along axis 36 from the diverter outlet 124 to the outlet 148 of riser pipe 90 .
Although the first flow channel shown in FIG. 4 has been described as having only two spiral flow portions 112 , 114 , separated by the second flow channel having one annular flow channel portion 130 , there may be any suitable number of first flow channel portions and second flow channel portions as shown in FIG. 5 . Accordingly any number of diverters 110 and riser pipes 88 , 90 , 132 , 134 that are needed to accommodate the fluid cooling requirements of the surface profile or contour of the sheet being produced by the process can be added to the roll. For example, FIG. 5 shows six spiral flow channel portions 112 , 114 , 160 , 161 , 162 , 163 of the first fluid flow channel, each separated by one of five secondary fluid flow channels having portions 130 , 164 , 165 , 166 , 167 .
Also, the direction of fluid flow in either or both of the spiral fluid flow channel portions 112 , 114 and the annular channel portion 130 can be reversed so that fluid flows clockwise in one channel and counterclockwise in another channel when viewed from a lateral side of the roll. Each flow channel can also contain a different fluid. The linear flow rate of fluid and mass flow rates of fluid in each channel may differ mutually. Further, the flow channels can be provided with turbulators and other such devices for increasing the degree of turbulent fluid flow through the channels in order to increase the rate of heat transfer through the various portions of the outer shell wall.
Furthermore, the first and second flow channels need not be cylindrical spirals and annular, as described here, but may have any suitable form and combination. The axial width of the various portions of the first flow channel may be mutually equal or they may differ from one another to optimize heat transfer. Similarly, the axial width of the second flow channel portions may differ mutually and in relation to the widths of the first flow channel portions in accordance with the cooling requirements of the sheet being produced.
Although the invention has been shown in connection with certain specific embodiments, it will be readily apparent to those skilled in the art that various changes in form and arrangement of parts and method steps may be made to suit requirements without departing from the spirit and scope of the invention. | A heat transfer roll for producing sheet material, particularly material having a cross-section whose thickness varies across the width of a sheet being formed, includes a journal on which the roll is rotatably supported, and at least two cooling channels at the surface of the roll that can be supplied with various fluids at various flow rates and temperatures. Fluid in the first and second channels flows at predetermined longitudinal positions at the roll surface. The first channel includes cylindrical spiral portions and the second channel includes a circular cylindrical channel located between the spiral portions. A diverter provides hydraulic flow continuity across the second flow channel to first and second portions of the first flow channel. Risers carry fluid radially outward to the flow channels at the outer surface of the roll. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation of Provisional Patent Application Ser. No. 61/222,344, filed Jul. 1, 2009, entitled “Symmetric Roof Spoiler” the disclosure of which is hereby incorporated by reference herein.
FIELD OF THE INVENTION
The present invention relates to roofing systems. More particularly, it relates to an apparatus and a method for reducing wind damage to a roof.
BACKGROUND OF THE INVENTION
One of the worst types of structural damage that can befall a building is roof damage. The devastation caused by high winds, hurricanes, tornadoes and the like is depicted by the media, often by focusing on the damage done to homes, especially to the roofs of those homes. In these cases, damage to the roof often leads to tremendous damage to the rest of the building, as a result of structural damage, and damage caused by the elements, such as rain or snow.
The roof of a building serves a number of purposes. First, it protects the interior of the building from the elements, such as rain, snow and hail. It also serves as an important structural component of the building, often linking the walls together, and adding strength to the building.
Wind causes several different types of damage to a roof. First, the wind, when blowing in a certain direction, can flow between the roof covering and the underlying substrate. This air flow can cause the roof covering to peel up and lift itself off the roof. The removal of the roof covering leaves the exposed roof susceptible to water, which can now enter through the area that is no longer protected by the missing covering. A second type of damage is caused by the effect of high speed attached flow over the surface of the roof. The deflection of the flow over the roof line squeezes the streamlines closer together, accelerating the speed and lowering the static pressure in accordance with Bernoulli's principle. This causes uplift on part or all of the roof structure, thereby exerting an upward force on the roof. This force not only causes the roof covering to lift from the roof, but can also cause the roof to pull away from the joists to which it is attached.
Various attempts have been made to reduce the destructive effect of hurricane force winds on a roof, including various types of roof spoilers or wind deflectors. For example, various types of roof wind spoilers have been disclosed, for example, in U.S. Pat. No. 2,206,040, U.S. Pat. No. 2,270,537, U.S. Pat. No. 2,270,538, U.S. Pat. No. 6,601,348, and U.S. Patent Application Publication 2006/0248810. Most of these spoilers are attached directly onto the roof surface. To achieve their goal, most employ a member that, when deployed, is orthogonally disposed to the roof surface. This member may be either permanently disposed, or manually or automatically disposed only when needed. Other publications, for example U.S. Pat. No. 6,601,348, and U.S. Patent Application Publication 2007/0113489, disclose a spoiler that can be attached to the fascia, rather than the roof surface. As the air flow travels along the surface of the roof, this vertical barrier presents an obstacle to its continued flow. As a result, the wind must travel over the barrier, which causes the air flow to become turbulent. In fact, the air flow directly at the roof may reverse directions, thereby pushing the roof covering down. The turbulent nature of the air flow created by these spoilers significantly decreases the negative pressure area described above. FIG. 1 a shows the flow of air over a typical roof. Note the attached flow as the wind moves over the roof surface. FIG. 1 b shows the resulting air flow when a roof spoiler is installed on the roof. Note the turbulence created downwind of the spoiler. Also of interest is the change in the direction of the wind along the roof surface.
Up to now, no roof spoilers have enjoyed commercial success or gained widespread use. This lack of success is probably due to a number of reasons, including unattractive appearance (e.g., due to poor aesthetic design or location on roof surface), poor performance (e.g., due to product design, operation or location), costs, complexity of installation, etc.
Therefore, it is an object of the present invention to provide a roof spoiler device that creates a turbulent air flow on the roof surface to prevent wind damage. It is an additional object to provide a device that reduces the flow of air under the roof covering. It is a further object to provide a roof spoiler device that has an acceptable aesthetic appearance. It is also an object to provide a roof spoiler device that may be used in conjunction with a roof gutter.
SUMMARY OF THE INVENTION
The present invention embraces a roof spoiler that effectively disrupts the attached flow of wind on a roof surface. Preferably, the spoiler is specially designed for installation with a gutter mounted on the roof fascia or along the leading edge of the roof. This spoiler utilizes a hinged design to move between two operating positions. The first position is a stowed position, whereby the spoiler extends beyond the gutter and is designed to be nearly invisible to passersby. In the stowed position, a portion of the spoiler covers the outer edge of the gutter (if present). A second portion of the spoiler may extend outward from the gutter.
The second position is a deployed position, wherein a barrier is projected vertically, or substantially vertically, so as to disrupt the flow of air over the roof surface. In one embodiment, the spoiler rests upon the roof covering when in the deployed position. In another embodiment, the spoiler rests near or against the gutter or holding bracket.
In one embodiment, a bracketing system, or support structure, is placed around an existing gutter. The roof spoiler is then pivotally attached to this support structure. In another embodiment, the support structure attaches directly to the gutter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts airflow over a roof surface with and without a roof spoiler;
FIG. 2 depicts a cross-section of a first embodiment of a roof spoiler of the present invention, in the stowed position.
FIG. 3 depicts the roof spoiler of FIG. 2 in the deployed position;
FIG. 4 a depicts an exploded view of one embodiment of the support structure used in the present invention;
FIG. 4 b depicts an assembled view of the embodiment of FIG. 4 a;
FIG. 5 depicts an exploded view of one embodiment of the roof spoiler used with the present invention;
FIG. 6 depicts a cross-section of a second embodiment of a roof spoiler of the present invention, in the stowed position.
FIG. 7 depicts the roof spoiler of FIG. 6 in the deployed position;
FIG. 8 depicts a cross-section of a first embodiment of a roof spoiler of the present invention used with a tile roof, in the stowed position;
FIG. 9 depicts the roof spoiler of FIG. 4 in the deployed position;
FIG. 10 depicts a cross-section of a second embodiment of a roof spoiler of the present invention, in the stowed position;
FIG. 11 depicts the roof spoiler of FIG. 10 in the deployed position;
FIG. 12 depicts a cross-section of the roof spoiler of FIG. 11 with a wind guard; and
FIG. 13 depicts the roof spoiler of FIG. 12 where the first member moves past orthogonal to the roof surface.
DETAILED DESCRIPTION OF THE INVENTION
A roof spoiler is intended to present an obstacle to attached flow during high (e.g., hurricane-force) winds. One way to present such an obstacle is to introduce a vertical, or substantially vertical member that interrupts that air flow. In other embodiments, the obstacle may not be vertical, but rather orthogonal to the roof surface, as shown in FIG. 1 b . However, as mentioned above, a vertical member attached to the roof surface is unsightly and not likely to be adopted.
To improve the aesthetics of a roof spoiler, it is preferable that the spoiler has at least two operating positions; a deployed position, where it acts as an obstruction as described above, and a stowed position, where the spoiler should be relatively non-intrusive and barely visible to passersby.
One embodiment of such a roof spoiler is depicted in FIG. 2 , which shows a cross-section of a first embodiment of the roof spoiler in the stowed position. The roof spoiler 100 is preferably L-shaped, with two roughly orthogonal members; a first member 110 and a second member 120 . Each member has a length (i.e., the short dimension that extends away from the roof edge) and a width (i.e., the long dimension parallel to the roof edge) and preferably is substantially planar. In the stowed position, the first member 110 is disposed in an approximately vertical orientation, extending downwardly on the outside of the gutter 130 (if a gutter is desired and present). In some embodiments, the first member may be disposed orthogonal (i.e., at approximately a 90° angle) to the roof surface. This first member 110 can be any suitable length, such as 15 cm to 31 cm, preferably about 20 cm to 24 cm.
The second member 120 is disposed in an approximately horizontal orientation, extending away from the gutter 130 . In some embodiments, such as the one shown in FIG. 2 , the second member may be perpendicular to the first member. The second member 120 can be of any suitable length, such as 15 cm to 31 cm, preferably about 20 cm to 24 cm. Preferably, the length of the second member 120 is greater than the distance from the pivot connection 142 to the roof edge. This allows the second member 120 to rest upon the roof 10 in the deployed position.
FIG. 3 shows the spoiler of FIG. 2 in the deployed position. As stated above, in one embodiment, the second member 120 is sufficiently long so that it extends to and rests upon the roof 10 in this position. In another embodiment, the second member 120 rests on the support structure 170 in the deployed position. Although the first member 110 and the second member 120 are shown as being orthogonal, the invention is not so limited. The angle formed between the two members can vary. For example, in one embodiment, the angle is less than 90 degrees, such that the first member 110 is vertical.
The members 110 , 120 are constructed from a durable material, such as metal, alloys, composites, plastics (such as PVC and ABS), polymers, polymer composites, and building materials, such as wood or wood composites, cement, or cemtitious boards. Factors such as strength, durability, ultraviolet and corrosion resistance, manufacturability and cost may be used to select an appropriate material. In some embodiments, the two members are formed as a unitary piece, which is preferably extruded to reduce cost. In some embodiments, the two members are the same thickness, while in other embodiments, the thicknesses of the two members differ. The thickness of each member is determined based on the material used and the desired durability and rigidity of that member.
The roof spoiler 100 is in communication with a pivoting mechanism 140 , such as a hinge. The roof spoiler 100 is configured to operate with the pivoting mechanism 140 such that it rotates from about 150° to about 180°, from its stowed position to its deployed position. In some embodiments, the pivoting mechanism 140 is a simple hinge, such as shown in FIG. 2 .
In this embodiment, the roof spoiler is positioned beyond the gutter 130 by means of one or more brackets. In FIG. 2 , the support structure 170 is comprised of a top horizontal bracket 171 , a bottom horizontal bracket 173 , and a vertical bracket 172 . These brackets form a frame that surrounds the gutter 130 , thereby supporting the roof spoiler 100 without requiring any mechanical support from the gutter 130 . In some embodiments, brackets 171 , 172 , 173 form a unitary piece, designed to be affixed to the fascia. In other embodiments, the brackets are individual pieces, which can be pre-assembled, or assembled on site to match the size of the gutter that it is intended to surround. These pieces may be made of any suitable material including metals, such as aluminum or steel. FIGS. 4 a - b show one embodiment where a number of separate components are used to create the support structure 170 .
FIG. 4 a shows an exploded view of one embodiment of the support structure 170 . FIG. 4 b shows an assembled version of this embodiment. In this embodiment, the top horizontal bracket is made up of a top mounted bracket 181 and a top corner bracket 182 . Both brackets 181 , 182 have a slot, such that a fastener 190 , such as a bolt, may be placed through the two slots. The fastener 190 may be mated with a corresponding nut 191 and an optional washer 192 . The fastener 190 is tightened at the position where the overall length of brackets 181 , 182 , as assembled, is longer than the gutter that it seeks to surround. The bottom horizontal bracket is also made up of two components, bottom mounted bracket 185 and bottom corner bracket 186 . As described above, a fastener 190 may be used to hold these two components together. In one embodiment, the lengths of the top and bottom assembled brackets is the same. The vertical bracket is comprised of top corner bracket 182 and bottom corner bracket 183 . A third fastener 193 may be used to hold these two components together. Top mounted bracket 181 and bottom mounted bracket 186 are shown as each having a pivoting connection 183 , 187 , respectively. These pivoting connections allow the mounted brackets 181 , 185 to be installed on the fascia 160 , regardless of the angle of the fascia. In other words, the top mounted bracket 181 may be affixed to the fascia at a right angle, while the bottom mounted bracket 185 may be affixed to the fascia at a different angle. FIG. 2 shows the top mounted bracket 181 connected at a right angle, while the bottom mounted bracket 185 is connected in a straight line to the bottom of the fascia. In another embodiment, the bottom mounted bracket 185 may also be connected perpendicularly to the fascia, or at any other angle.
While FIG. 4 shows 4 bracket pieces with pivoting connections to the fascia, the disclosure is not limited to this embodiment. For example, the entire support structure 170 may be one unitary piece. In another embodiment, the corner brackets 182 , 186 may be a unitary piece, which is made to surround most common sized gutters. In certain embodiments, cost can be reduced by having the top and bottom mounted brackets 181 , 185 be the same component. Similarly, the top and bottom corner brackets 182 , 186 may also be a common part, if desired. In this way, the assembly shown in FIG. 4 a may be comprised of 2 mounted brackets with pivoting connections, two corner brackets, three bolts, three nuts and three washers.
In another embodiment, the mounted brackets 181 , 185 may not have pivoting connections. Rather their connection points may be fixed at a predetermined angle, such as perpendicular or colinear.
In yet another embodiment, the support structure 170 may not comprise all three components (top bracket 171 , bottom bracket 173 , and vertical bracket 172 ). For example, the support structure may only have a top bracket, firmly affixed to the fascia, which is used to support the roof spoiler 100 . Note that the use of a three-part support structure 170 (as shown in FIG. 2 ), or the 4-part structure (shown in FIG. 4 ) is not meant to limit the invention, rather it simply depicts several embodiments of the support structure 170 .
Roof spoiler 100 is connected to support structure 170 via a pivoting mechanism 140 . The pivoting mechanism may be a simple hinge, as shown in FIG. 4 . In this figure, the hinge 195 includes a pivoting connection 142 , a first portion 141 mounted to the support structure 170 , and a second portion connected 143 to the roof spoiler 100 . The first portion 141 is shown connected to the top and bottom corner brackets 182 , 186 in this figure. A fastener is used to connect these three components together. However, other methods of affixing a pivoting connection 142 to the support structure 170 are also within the scope of the invention. The first portion 141 is pivotally attached to the second portion 143 , which is attached to the roof spoiler 100 .
FIG. 5 shows an exploded view of a roof spoiler 100 that can be used with the present invention. In this embodiment, first member 110 and second member 120 are extruded as a unitary piece. A support bar 115 , preferably made of metal or another suitable material, is fastened to the second portion 143 of the hinge 195 , thereby sandwiching the first member 110 between the second portion 143 and the support bar 115 and holding it in place. A fastener 194 may be used to connect the support bar 115 , the first member 110 and the second portion 143 of the hinge 195 . In other embodiments, the first member 110 is attached directly to the second portion 143 . The actual attachment mechanism is purely illustrative and other methods of attaching the spoiler 100 to the pivoting connection 142 are understood by those of ordinary skill in the art and are within the scope of the invention.
For example, in another embodiment, no support structure 170 is provided. Rather, the pivoting mechanism 140 is attached directly to the gutter 130 . This attachment can be permanent, such as via a fastener. In other embodiments, the roof spoiler 100 may connect to the gutter via a clip-on attachment. Such an embodiment requires the gutter to support the weight of the spoiler 100 , as well as the force exerted on it during a high speed wind storm. Such an embodiment is shown in FIG. 6 . In this embodiment, a support structure 175 is placed over the lip of the gutter 130 . As before, pivoting mechanism 140 is connected to the support structure 175 . In another embodiment, a fastener, such as wingnut 176 , is used to secure support structure 175 to the gutter 130 . In this embodiment, the support structure 175 is slipped over the lip of the gutter 130 . The wingnut 176 is then tightened so as to securely attach the support structure 175 to the gutter 130 .
Returning to FIG. 5 , the roof spoiler may optionally have a decorative insert 117 located in the angle formed between the first member 110 and the second member 120 . Since the roof spoiler is visible while in its stowed position, such a decorative insert improves the aesthetic value of the spoiler. Such an insert also serves to conceal the support bar 115 , or any fasteners used to attach the spoiler 100 to the pivoting mechanism 140 . In some embodiments, endcaps 119 may be placed on the ends of the roof spoilers. These endcaps 119 may serve two purposes. Like the insert 117 , these components have an aesthetic value. They also have structural value in that they may hold the first member 110 and second member 120 at their intended angle, in the presence of high speed wind.
FIG. 7 shows a side view of the roof spoiler of FIG. 5 . In this embodiment, the support bar 115 is positioned against to the first member 110 , near the junction of the second member 120 . Fasteners 194 may be used to secure the support bar 115 , the first member 110 to the pivoting mechanism 140 . Decorative insert 117 is shown to have multiple arcuate surfaces. These surfaces are purely illustrative and any surface or pattern of surfaces may be used. For example, the insert may be form so as to resemble a piece of crown molding if desired. In one embodiment, the first and second members are extruded and may have clips 119 extending from their inner surfaces. These clips 119 may be used as an inexpensive method of holding the insert 117 in place, as shown in FIG. 7 . In this embodiment, the insert is form from a somewhat pliable material, such as a plastic. The insert 117 is then inserted into one of the two clips 119 . The insert is then slightly squeezed or compressed so that its opposite edge can be inserted into the other dip.
In some embodiments, a thicker roof, such as a tile roof, may be used with the present invention. In such an embodiment, the roof spoiler may be attached in a number of ways. In one embodiment, shown in FIGS. 8 and 9 , the same mechanism as was used in FIG. 2 is employed. In this embodiment, the angle of the first member 110 with respect to the roof deviates further from orthogonal than with a flat roof (as shown in FIG. 3 ).
In another embodiment, the pivoting connection 142 is adjusted vertically such that the second member 120 lays flat on the roof, and the first member 110 extends orthogonally from the plane of the roof. This embodiment is shown in FIG. 10 and FIG. 11 . In this embodiment, since the pivoting connection 142 is positioned to be planar with the roof surface, the second member 120 lies flat on the roof. This allows first member 110 to extend orthogonally from the place of the roof.
One potential issue associated with the embodiment of FIG. 11 is the possibility that wind will blow in the gap defined between the gutter 130 and the roof spoiler 100 , while it is in the deployed position. This wind can then be tunneled beneath the tile roof, thereby separating it from the surface of the building. In one embodiment, this gap is closed by utilizing a solid first portion 141 of pivoting mechanism 140 . This first portion would block the gap from the gutter 130 to the pivoting connection 142 , thereby keeping wind out.
In another embodiment, a thinner first portion 141 , such as that shown in FIG. 4 a is used. In this embodiment, a wind guard is inserted in the gap between the gutter and the pivoting connection. For example, referring to FIG. 4 a , a wind guard may be installed between the first portion 141 and the top and bottom corner brackets 182 , 186 . This wind guard may be a solid coplanar piece, made of material such as that used for the first and second members. In another embodiment, the wind guard is rotatably attached to the pivoting connection 142 . In this way, it can move freely with the deployment of the spoiler such that no gap is present between the spoiler and the roofing material. FIG. 12 shows wind guard 147 in its installed position, while the spoiler 100 is in the deployed position.
The roof spoiler in these embodiments is intended to pivot from a stowed position, where the first member 110 is substantially vertical and the second member is substantially horizontal, to a deployed position where the second member 120 is preferably coplanar with the roof surface and the first member 110 extends orthogonally upward from the plane of the roof surface. In other words, in one embodiment, the first member moves from extending vertically downward to extending upward after going through a rotation of 180-θ°, where θ is the pitch of the roof. In another embodiment, the spoiler rotates less than 180-θ°, where θ is the pitch of the roof, such as the embodiment of FIG. 9 . In another embodiment, the spoiler rotates slightly more than 180-θ°, such as is shown in FIG. 13 . | Disclosed is a roof spoiler that effectively disrupts the attached flow of wind on a roof surface. Preferably, the spoiler is specially designed for installation with a gutter mounted on the roof fascia or along the leading edge of the roof. This spoiler utilizes a hinged design to move between two operating positions. The first position is a stowed position, whereby the spoiler extends beyond the gutter and is designed to be nearly invisible to passersby. In the stowed position, a portion of the spoiler covers the outer edge of the gutter (if present). A second portion of the spoiler may extend outward from the gutter. The second position is a deployed position, wherein a barrier is projected vertically, or substantially vertically, so as to disrupt the flow of air over the roof surface. In one embodiment, the spoiler rests upon the roof covering when in the deployed position. In another embodiment, the spoiler rests near or against the gutter or holding bracket. In one embodiment, a bracketing system, or support structure, is placed around an existing gutter. The roof spoiler is then pivotally attached to this support structure. In another embodiment, the support structure attaches directly to the gutter. | 4 |
FIELD OF THE INVENTION
The present disclosure relates to a fuel cell assembly and more particularly to header manifolds for reactants and coolant supplied to and removed from a fuel cell stack.
BACKGROUND OF THE INVENTION
Fuel cell systems are increasingly being used as a power source in a wide variety of applications. Fuel cell systems have been proposed for use in power consumers such as vehicles as a replacement for internal combustion engines, for example. Such a system is disclosed in commonly owned U.S. patent application Ser. No. 10/418,536, hereby incorporated herein by reference in its entirety. Fuel cells may also be used as stationary electric power plants in buildings and residences, as portable power in video cameras, computers, and the like. Typically, the fuel cells generate electricity used to charge batteries or to provide power for an electric motor.
Fuel cells are electrochemical devices which combine a fuel such as hydrogen and an oxidant such as oxygen to produce electricity. The oxygen is typically supplied by an air stream. The hydrogen and oxygen combine to result in the formation of water. Other fuels can be used such as natural gas, methanol, gasoline, and coal-derived synthetic fuels, for example.
The basic process employed by a fuel cell is efficient, substantially pollution-free, quiet, free from moving parts (other than an air compressor, cooling fans, pumps and actuators), and may be constructed to leave only heat and water as by-products. The term “fuel cell” is typically used to refer to either an individual cell or a plurality of cells depending upon the context in which it is used. The plurality of cells is typically bundled together and arranged to form a stack with the plurality of cells commonly arranged in electrical series. Since individual fuel cells can be assembled into stacks of varying lengths, systems can be designed to produce a desired energy output level providing flexibility of design for different applications.
The stacks may comprise of more than one hundred individual bipolar plates, wherein successive plates and a membrane-electrode-assembly (MEA) disposed therebetween form the individual cell. Typically, apertures formed in successive bipolar plates cooperate to form a “header” running the length of the fuel cell stack. The plate formed header distributes reactants (such as oxygen and hydrogen) and coolant to the individual cells. A first end of the plate formed header is sealingly disposed against an end unit, wherein an injector, a recycler, a reactant source, a humidifier, or other support system is typically disposed. A second end of the plate formed header is sealingly disposed against an end plate or a second end unit.
Bipolar plates include active and inactive areas formed thereon. The electrochemical reaction occurs in active areas of the bipolar plates. Inactive areas are used to guide reactants and coolants across portions of the plate, provide sealing surfaces for gasket material, form apertures in the plate, and provide structural support for the plate. Large areas of inactive areas on plates result in an inefficient use of the plate and a gasket used to form the individual cells.
Fuel cell stacks of varying number of cells require different amounts of reactants and coolant to operate properly. Apertures formed in the bipolar plates may be sized to optimize reactant and coolant flow rates to and from the fuel cell stack. A stack having a larger number of cells, and thus a longer stack length requires plate formed headers capable of carrying more reactants and coolant, necessitating larger apertures in the plates. As a result, a particular plate design is limited to a relatively narrow range of stack lengths, and a manufacturer may be required to support multiple plate designs to accommodate a number of vehicles having a large differential of energy requirements.
Fuel cell stacks require a close stacking alignment and adequate sealing between successive plates. Sealing surfaces formed on the plates and the MEAs must be properly aligned to form the fuel cell stack that operates efficiently, militates against leakage of reactants and coolant, and electrically isolates successive plates from one another.
Plate formed headers have a consistent cross-sectional shape along a header length when a single plate design is used to form the fuel cell stack. A consistent cross sectional shape may be undesirable for to the fuel cell stack because a pressure differential may exist along the length of the header, causing differences in reactant and coolant flow rates into individual cells. Additionally, plate formed headers limit header access to ends of the fuel cell stack for placement of components such as a distribution manifold, a water separator, and an infector, for example, necessary for operation of the fuel cell stack.
It would be desirable to produce a discrete header for a fuel cell stack, wherein the discrete header minimizes use of the plate and the gasket materials, allows a single plate design to be used for multiple stack lengths having a large differential of energy requirements, provides a durable alignment mechanism for the fuel cell stack, and provides integration flexibility for components and configurations of the fuel cell stack.
SUMMARY OF THE INVENTION
Presently provided by the invention, a discrete header for a fuel cell system that minimizes use of the plate and the gasket materials, allows a single plate design to be used for multiple fuel cell stack lengths having a large differential of energy requirements, provides a durable alignment mechanism for the fuel cell stack, and provides integration flexibility for components and configurations of the fuel cell system, has surprisingly been discovered.
In a first embodiment, the fuel cell system, comprises a fuel cell plate including a first partial header, and a main body including a second partial header and a fastening point, the fastening point coupled to the plate, the fastening point of the main body securing the main body to the plate to form a header between the first partial header and the second partial header.
In another embodiment, the fuel cell system comprises a plurality of fuel cell plates aligned to form a fuel cell stack, the stack including a first partial header and a channel, a plurality of membrane electrode assemblies at least partially formed from a gasket material, the membrane electrode assemblies disposed between the fuel cell plates, a discrete header section including a second partial header, and a fastening point disposed on the discrete header section, the fastening point extending along a length of the discrete header section, the fastening point being a flanged protuberance substantially conforming to a shape of the channel, wherein the fastening point is coupled to the channel to form a header from the first partial header and the second partial header.
In a further embodiment, a fuel cell system comprises a plurality of fuel cell plates aligned to form a fuel cell stack, the stack including a first partial header and a channel, a plurality of membrane electrode assemblies at least partially formed from a gasket material, the membrane electrode assemblies disposed between the fuel cell plates, a discrete header section including a second partial header and one of a fluid inlet and a fluid outlet formed in the second partial header at an intermediate position along a length of the discrete header section, a fastening point disposed on the discrete header section, the fastening point extending along the length of the discrete header section, the fastening point being a flanged protuberance substantially conforming to a shape of the channel, and a fastening keyway formed in the fastening point, the fastening keyway extending along a length of the discrete header for receiving a header key, wherein the fastening point expands when the header key is inserted into the fastening keyway, the fastening point abutting one of the channel and the plurality of membrane electrode assemblies disposed between the plurality of fuel cell plates, securing the discrete header section to the stack to form a header from the first partial header and the second partial header.
DRAWINGS
The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of embodiments of the invention when considered in the light of the accompanying drawings in which:
FIG. 1 is an exploded perspective view of an illustrative fuel cell stack known in the art;
FIG. 2 is an exploded perspective view of an illustrative fuel cell stack according to the present invention;
FIG. 3 is an enlarged, fragmentary top plan view of the fuel cell stack shown in FIG. 2 , with a clamping plate, a first end seal, and a second end seal removed from the fuel cell stack;
FIG. 4 is an enlarged, fragmentary top plan view of the fuel cell system shown in FIG. 2 , with a clamping plate, a first end seal, and a second end seal removed from the fuel cell stack and showing a plurality of header keys inserted into a plurality of fastening points;
FIG. 5 is an enlarged, fragmentary top plan view of a discrete header according to another embodiment of the present disclosure;
FIG. 6 is an enlarged, fragmentary top plan view of the discrete header shown in FIG. 5 , shown coupled to a fuel cell stack;
FIG. 7 is an enlarged, fragmentary top plan view of a fuel cell stack including a discrete header according to another embodiment of the present disclosure; and
FIG. 8 is an enlarged, fragmentary top plan view of the fuel cell stack including the discrete header shown in FIG. 7 , including a sealant disposed between the fuel cell stack and the discrete header.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description and appended drawings describe and illustrate various embodiments of the invention. The description and drawings serve to enable one skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any manner.
FIG. 1 depicts a fuel cell stack 10 having a pair of membrane electrode assemblies 12 separated from each other by an electrically conductive bipolar plate 14 . For simplicity, only a two-cell stack (i.e. one bipolar plate) is illustrated and described in FIG. 1 , it being understood that the fuel cell stack 10 will typically have many more cells and bipolar plates.
The membrane electrode assemblies 12 and bipolar plate 14 are stacked together between a pair of clamping plates 16 , 18 and a pair of unipolar end plates 20 , 22 . The clamping plates 16 , 18 are electrically insulated from the end plates 20 , 22 by a seal or a dielectric coating (not shown). The unipolar end plate 20 , both working faces of the bipolar plate 14 , and the unipolar end plate 22 include respective active areas 24 , 26 , 28 , 30 . The active areas 24 , 26 , 28 , 30 are typically flow fields for distributing gaseous reactants such as hydrogen gas and air over an anode and a cathode, respectively, of the membrane electrode assemblies 12 .
The bipolar plate 14 is typically formed by a conventional process for shaping sheet metal such as stamping, machining, molding, or photo etching through a photolithographic mask, for example. In one embodiment, the bipolar plate 14 is formed from unipolar plates which are then joined by any conventional process such as welding or adhesion. It should be further understood that the bipolar plate 14 may also be formed from a composite material. In one particular embodiment, the bipolar plate 14 is formed from a graphite or graphite-filled polymer.
A plurality of nonconductive gaskets 32 , which may be a component of the membrane electrode assemblies 12 , are disposed between the bipolar plate 14 and the unipolar end plates 20 , 22 . The gaskets 32 militate against fuel cell leakage and provide electrical insulation between the plates 14 , 20 , 22 of the fuel cell stack 10 . Gas-permeable diffusion media 34 are disposed adjacent the membrane electrode assemblies 12 . The end plates 20 , 22 are also disposed adjacent the diffusion media 34 , respectively, while the active areas 26 , 28 of the bipolar plate 14 are disposed adjacent the diffusion media 34 .
The bipolar plate 14 , unipolar end plates 20 , 22 , and the membrane electrode assemblies 12 each include a cathode supply aperture 36 and a cathode exhaust aperture 38 , a coolant supply aperture 40 and a coolant exhaust aperture 42 , and an anode supply aperture 44 and an anode exhaust aperture 46 . A conventional supply header 48 of the fuel cell stack 10 is formed by an alignment of the respective apertures 36 , 42 , 46 in the bipolar plate 14 , unipolar end plates 20 , 22 , and the membrane electrode assemblies 12 . A conventional exhaust header 50 of the fuel cell stack 10 is formed by an alignment of the respective apertures 38 , 40 , 44 in the bipolar plate 14 , unipolar end plates 20 , 22 , and the membrane electrode assemblies 12 . The hydrogen gas is supplied to an anode supply header via an anode inlet conduit 52 . The air is supplied to a cathode supply header of the fuel cell stack 10 via a cathode inlet conduit 54 . An anode outlet conduit 56 and a cathode outlet conduit 58 are also provided for an anode exhaust header and a cathode exhaust header, respectively. A coolant inlet conduit 60 is provided for supplying liquid coolant to a coolant supply header. A coolant outlet conduit 62 is provided for removing coolant from a coolant exhaust header. It should be understood that the configurations of the various inlets 52 , 54 , 60 and outlets 56 , 58 , 62 in FIG. 1 are for the purpose of illustration, and other configurations may be chosen as desired.
FIG. 2 depicts a fuel cell stack 110 according to an embodiment of the present invention having a pair of membrane electrode assemblies 112 separated from each other by an electrically conductive bipolar plate 114 . For simplicity, only a two-cell stack (i.e. one bipolar plate) is illustrated and described in FIG. 2 , it being understood that the fuel cell stack 110 will typically have many more cells and bipolar plates.
The membrane electrode assemblies 112 and the bipolar plate 114 are stacked together between a pair of clamping plates 116 , 118 and a pair of unipolar end plates 120 , 122 . The clamping plates 116 , 118 are typically electrically insulated from the end plates 120 , 122 by a seal or a dielectric coating (not shown). As illustrated, the clamping plates 116 , 118 may be one of a cap plate and a header plate. The unipolar end plate 120 , both working faces of the bipolar plate 114 , and the unipolar end plate 122 include respective active areas 124 , 126 , 128 , 130 . The active areas 124 , 126 , 128 , 130 are typically flow fields for distributing gaseous reactants such as hydrogen and air over an anode and a cathode, respectively, of the membrane electrode assemblies 112 .
The bipolar plate 114 is typically formed by a conventional process for shaping sheet metal such as stamping, machining, molding, or photo etching through a photolithographic mask, for example. In one embodiment, the bipolar plate 114 is formed from unipolar plates which are then joined by any conventional process such as welding or adhesion. It should be further understood that the bipolar plate 114 may also be formed from a composite material or other materials. In one particular embodiment, the bipolar plate 114 is formed from a graphite or graphite-filled polymer.
A plurality of nonconductive gaskets 132 , which may be a component of the membrane electrode assemblies 112 , is disposed between the bipolar plate 114 and the unipolar end plates 120 , 122 . The gaskets 132 militate against fuel cell leakage and provide electrical insulation between the plates 114 , 120 , 122 of the fuel cell stack 10 . Gas-permeable diffusion media 134 are disposed adjacent the membrane electrode assemblies 112 . The end plates 120 , 122 are also disposed adjacent the diffusion media 134 , respectively, while the active areas 126 , 128 of the bipolar plate 114 are disposed adjacent the diffusion media 134 .
The bipolar plate 114 , unipolar end plates 120 , 122 , and the membrane electrode assemblies 112 each include a cathode supply region 136 and a cathode exhaust region 138 , a coolant supply region 140 and a coolant exhaust region 142 , and an anode supply region 144 and an anode exhaust region 146 . A first plurality of partial first headers of the fuel cell stack 110 is formed by an alignment of the respective regions 136 , 142 , 146 in the bipolar plate 114 , unipolar end plates 120 , 122 , and the membrane electrode assemblies 112 . A first discrete header section 147 having a second plurality of partial first headers is sealingly engaged with the bipolar plate 114 , the unipolar end plates 120 , 122 , and the membrane electrode assemblies 112 to form a plurality of first headers 148 . A first plurality of partial headers of the fuel cell stack 110 is formed by an alignment of the respective region 138 , 140 , 144 in the bipolar plate 114 , unipolar end plates 120 , 122 , and the membrane electrode assemblies 112 . A second discrete header section 149 having a second plurality of partial first headers is sealingly engaged with the bipolar plate 114 , unipolar end plates 120 , 122 , and the membrane electrode assemblies 112 to form a plurality of second headers 150 . The hydrogen gas is supplied to an anode supply header via an anode inlet conduit 152 . The air is supplied to a cathode supply header of the fuel cell stack 110 via a cathode inlet conduit 154 . An anode outlet conduit 156 and a cathode outlet conduit 158 are also provided for an anode exhaust header and a cathode exhaust header, respectively. A coolant inlet conduit 160 is in fluid communication with the discrete header section 147 for supplying liquid coolant to a coolant supply header. A coolant outlet conduit 162 is in fluid communication with the discrete header section 149 for removing coolant from a coolant exhaust header. It should be understood that the configurations of the various inlets 152 , 154 , 160 and outlets 156 , 158 , 162 in FIG. 2 are for the purpose of illustration, and other configurations may be chosen as desired. For example, the coolant inlet conduit 160 and the coolant outlet conduit 162 may be formed on the clamping plates 116 , 118 .
Adequate sealing must be provided between the discrete header sections 147 , 149 and the clamping plates 116 , 118 . A plurality of end seals 163 is disposed at a first end and a second end of the discrete header sections 147 , 149 . The end seals 163 are disposed between the discrete header sections 147 , 149 and one of the clamping plates 116 , 118 . The end seals 163 may be disposed in one of recesses (not shown) formed in the clamping plates 116 , 118 corresponding to a shape of the end seals 163 and recesses formed in the first end and the second end of the discrete header sections 147 , 149 . Alternately, a recess (not shown) may be formed in the end seals 163 corresponding to one of the first end and the second end of the discrete header sections 147 , 149 , one of the first end and the second end of the discrete header sections 147 , 149 disposed in the recess formed in the end seals 163 .
Adequate sealing must also be provided between the discrete header sections 147 , 149 and the plates 114 , 120 , 122 . Sealing between the discrete header sections 147 , 149 and the plates 114 , 120 , 122 militates against a mixing of the reactants and the coolant. Further, sealing between the discrete header sections 147 , 149 and the plates 114 , 120 , 122 militates against the reactants and the coolant from leaking from the fuel cell stack 110 .
FIG. 3 depicts a first embodiment of the discrete header section 147 . The discrete header section 147 comprises a unitary main body 168 . The discrete header section 147 includes a partial header 170 and a fastening point 172 . The discrete header section 147 includes three partial headers 170 and four fastening points 172 . Only two partial headers 170 and three fastening points 172 are shown in FIG. 3 . The discrete header section 147 is typically formed from a non-conductive material such as a plastic and a plastic composite, for example. The discrete header section 147 may be produced by any conventional process such as a molding process and a machining process, for example.
The partial headers 170 illustrated are substantially semi-circular in cross section, and extend along a length of the discrete header section 147 . Other arcuate shapes, rectangular shapes, angular shapes, or any combination thereof may be used. The shape of the partial headers 170 may also vary along the length of the discrete header section 147 . The partial headers 170 may be formed to increase or decrease a cross-sectional area of the supply headers and the exhaust headers over a length of the discrete header section 147 . A plurality of liquid management features 171 is disposed on an inner wall of the partial header 170 to militate against liquid retention within the supply headers and the exhaust headers. The liquid management features 171 may be integrally formed with the partial header 170 , formed separate from the partial header 170 and coupled thereto, or formed on the partial header 170 by a secondary operation. One of a hydrophilic coating and a hydrophobic coating may also be applied to the partial header 170 to facilitate liquid management within one of the supply headers and the exhaust headers. As shown, the discrete header section 170 includes the coolant inlet conduit 160 integrally formed therewith at an intermediate position along the length of the discrete header section 147 . It should be understood that the configuration of the coolant inlet conduit 160 shown in FIG. 2 is for the purpose of illustration, and other configurations of the conduits 152 , 154 , 156 , 158 , 160 , 162 formed with the discrete header sections 147 , 149 may be chosen as desired.
An interface of the discrete header sections 147 , 149 and the plates 114 , 120 , 122 is formed by a fastening point 172 formed on the discrete header sections 147 , 149 and a fastening channel 173 formed in the plates 114 , 120 , 122 . The fastening point 172 extends along a length of the discrete header and slidingly engages the fastening channel 173 to secure the discrete header section 147 to the fuel cell stack 110 . A plate partial header 174 is formed adjacent the fastening channel 173 . The plate partial header 174 includes one of inlets and outlets of the plates 114 , 120 , 122 that are in fluid communication with one of the active areas 124 , 126 , 128 , 130 and an interior cavity of the bipolar plate 114 . As shown, four fastening channels 173 are located between and on each side of the plate partial headers 174 , but any configuration of the fastening channels 173 and the plate partial headers 174 may be chosen as desired.
As shown, the fastening point 172 is integrally formed with the discrete header section 147 . Alternately, the fastening point 172 may be formed separate from and coupled to the discrete header section 147 . The discrete header section 147 including the fastening point 172 is slidingly disposed in the fastening channel 173 of the fuel cell stack 110 . As shown, the fastening point 172 is a bifurcated flanged rectangular protuberance substantially corresponding to a shape of the fastening channel 173 , but any other shape may be used. A fastening keyway 176 is formed by the bifurcations in the fastening point 172 , the fastening keyway 176 extending along a length of the discrete header section 147 . The fastening keyway 176 is shown as being substantially rectangular in shape and having an open side to allow for expansion of the fastening point 172 , but any shape may be used. The fastening point 172 includes at least one retention notch 177 . As shown, the fastening point 172 includes two retention notches 177 formed therein. The retention notches 177 are rectangularly shaped and formed in opposing sides of the fastening point 172 , but other shapes and arrangements of the retention notches 177 may be used.
The fastening channel 173 is formed by the alignment of a plurality of plate slots formed in the plates 114 , 120 , 122 . The fastening channel 173 is rectangular in shape and substantially corresponds to a shape of the fastening point 172 . The plate slots each include at least one retention protuberance 178 . As shown, each plate slot includes retention protuberances 178 having a rectangular shape and substantially corresponding to a shape of the retention notches 177 formed in the fastening points 172 , but other shapes and arrangements of the retention protuberances 178 may be used.
FIG. 4 depicts the discrete header section 147 illustrated in FIG. 3 having a header key 180 disposed in the fastening keyway 176 . The fastening keyway 176 has a width smaller than a width of the header key 180 . A tapered or chamfered end of the header key 180 may be formed thereon to facilitate insertion of the header key 180 into the fastening keyway 176 . The insertion of the header key 180 into the fastening keyway 176 causes the width of the fastening keyway 176 to increase until the bifurcations of the fastening point 172 contact the fastening channel 173 , thereby securing the discrete header section 147 to the plates 114 , 120 , 122 . The discrete header section 147 secured to the plates 114 , 120 , 122 by the insertion of the header key 180 militates against a movement of the discrete header section 147 in relation to the plates 114 , 120 , 122 along a length of the discrete header section 147 .
The header key 180 inserted into the fastening keyway 176 also creates a seal between the discrete header section 147 and the plates 114 , 120 , 122 . MEAs 112 (not shown) disposed between the plates 114 , 120 , 122 are shaped to allow a portion of the MEAs 112 to enter the fastening channel 173 . When the header key 180 is inserted into the fastening channel 173 , the expanding fastening point 172 compresses the portion of the MEAs 112 entering the fastening channel 173 , creating a seal between the discrete header section 147 and the plates 114 , 120 , 122 .
FIGS. 5 and 6 show another embodiment of the invention similar to that shown in FIGS. 2 , 3 , and 4 . Reference numerals for similar structure in respect of the description of FIGS. 2 , 3 , and 4 are repeated in FIGS. 5 and 6 with a prime (′) symbol.
The discrete header section 147 ′ shown includes the fastening points 172 ′ having a plurality of sealing ridges 190 . The fastening point 172 ′ slidingly engages the fastening channel 173 ′ to secure the discrete header section 147 ′ to the fuel cell stack 110 ′. The fastening point 172 ′ is integrally formed with the discrete header section 147 ′. Alternately, the fastening point 172 ′ may be formed separate and coupled to the discrete header section 147 ′. As shown, the fastening point 172 ′ is a flanged rectangular protuberance substantially corresponds to a shape of the fastening channel 173 ′. The fastening point 172 ′ includes the sealing ridges 190 . Four sealing ridges 190 are formed on each of the fastening points 172 ′ as illustrated in FIGS. 5 and 6 , but any number may be used. The sealing ridges 190 are triangular in shape and are integrally formed with the fastening point 172 ′. Alternately, the sealing ridges 190 may be formed separately and coupled to the fastening point 172 ′.
FIG. 6 depicts the fastening points 172 ′ of the discrete header section 147 ′ illustrated in FIG. 5 inserted into the fastening channels 173 ′. The fastening point 172 ′ having the plurality of sealing ridges 190 has a width substantially corresponding to a width of the fastening channel 173 ′. Insertion of the discrete header section 147 ′ creates a seal between the discrete header section 147 ′ and the plates 114 ′, 120 ′, 122 ′. MEAs 112 ′ disposed between the plates 114 , 120 ′, 122 ′ are shaped to allow a portion of the MEAs 112 ′ to enter the fastening channel 173 ′. As shown, when the fastening point 172 ′ is inserted into the fastening channel 173 ′, the sealing ridges 190 ′ compress the portion of the MEAs 112 ′ entering the fastening channel 173 ′, creating a seal between the discrete header section 147 ′ and the plates 114 ′, 120 ′, 122 ′. Alternately, the sealing ridges 190 may cut into the portion of the MEAs 112 ′ entering the fastening channel 173 ′, creating a seal between the discrete header section 147 ′ and the plates 114 ′, 120 ′, 122 ′. Frictional forces between the sealing ridges 190 and the portion of the MEAs 112 ′ entering the fastening channel militate against a movement of the discrete header section 147 ′ in relation to the plates 114 ′, 120 ′, 122 ′ along a length of the discrete header section 147 ′.
FIGS. 7 and 8 show another embodiment of the invention similar to that shown in FIGS. 2 , 3 , and 4 . Reference numerals for similar structure in respect of the description of FIGS. 2 , 3 , and 4 are repeated in FIGS. 7 and 8 with a double prime (″) symbol.
The discrete header section 147 ″ shown in FIG. 7 includes the fastening points 172 ″. The fastening point 172 ″ slidingly engages the fastening channel 173 ″ to secure the discrete header section 147 ″ to the fuel cell stack 110 ″. The fastening point 172 ″ is substantially “T” shaped and is integrally formed with the discrete header section 147 ″. Alternately, the fastening point 172 ″ may be formed separate and coupled to the discrete header section 147 ″. Other shapes such as a circular, a triangular, or a bifurcated shaped may be used, for example. As shown, the fastening point 172 ″ corresponds to at least a portion of the fastening channel 173 ′ and includes at least one fastening flange 200 . As shown, two fastening flanges 200 form a portion of the fastening point 172 ″ having a width greater than at least a portion of the fastening channel 173 ″. A sealant cavity 202 corresponds to the portion of the fastening channel 173 ″ not occupied by the fastening point 172 ″.
FIG. 8 depicts the sealant cavity 202 having a sealant 204 disposed therein. The sealant 204 forms a seal between the fastening point 172 ″ of the discrete header section 147 ″ and the plates 114 ″, 120 ″, 122 ″. Any dielectric sealant insoluble to one of the reactants and the coolant used in the fuel cell stack 110 ″ may be used. The sealant 204 is disposed in the sealant cavity 202 through an injection process, a potting process, or other process, for example. After an appropriate curing time the sealant 204 solidifies, securing the discrete header section 147 ″ to the plates 114 ″, 120 ″, 122 ″. As shown, the sealant 204 is also applied in a bead between the partial header 170 ″ and the plate partial header 174 ″. The bead is applied along a length of the discrete header section 147 ″. The sealant 204 militates against a mixing of the reactants and the coolant. Further, the sealant 204 militates against the reactants and the coolant from leaking from one of the supply and the exhaust headers through the interface of the discrete header sections 147 ″ and the plates 114 ″, 120 ″, 122 ″.
In use, the discrete header section 147 , 147 ′, 147 ″, 149 for the fuel cell stack 110 , 110 ′, 110 ″ minimizes the amount of material used to form the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 and a gasket portion of the MEAs 112 , 112 ′. The material used to form the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 and a gasket portion of the MEAs 112 , 112 ′ is reduced because the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 and the MEAs 112 , 112 ′ do not encircle one of the supply and the exhaust headers for the fuel cell stack 110 , 110 ′, 110 ″ including the discrete header section 147 , 147 ′, 147 ″, 149 . The fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 used with the discrete header section 147 , 147 ′, 147 ″, 149 require the plate partial header 174 , 174 ′, 174 ″ and a plate slot (which collectively form the fastening channels 173 , 173 ′, 173 ″), minimizing an amount of inactive area on the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 and a plurality of sealing surfaces required for operation of the fuel cell stack 110 , 110 ′, 110 ″. The plurality of sealing surfaces required for the fuel cell stack 110 , 110 ′, 110 ″ including the discrete header section 147 , 147 ′, 147 ″, 149 are limited to a bead seal which encloses the active areas 124 , 126 , 128 , 130 of each fuel cell and the interfaces located between the discrete headers section 147 , 147 ′, 147 ″, 149 and the fastening channels 173 , 173 ′, 173 ″. As a result of minimizing the plurality of sealing surface required, reliability and cost effectiveness of the fuel cell stack 110 , 110 ′, 110 ″ is increased.
The fuel cell stack 110 , 110 ′, 110 ″ including the discrete header section 147 , 147 ′, 147 ″ increases the design flexibility of a fuel cell system into which the fuel cell stack 110 , 110 ′, 110 ″ is incorporated, Fuel cell systems having different fuel cell stack lengths may be produced to achieve a desired power requirement. The required amount of fuel and cooling needs of the fuel cell system may vary considerably depending on a length of the fuel cell stack. The fuel cell stack 110 , 110 ′, 110 ″ including the discrete header section 147 , 147 ′, 147 ″, 149 permits the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 and the MEAs 112 , 112 ′ to be used for fuel cell systems having different fuel cell stack lengths. As a non-limiting example, a fuel cell stack comprising of 300 fuel cells may have the supply headers and the exhaust headers about 50% larger in cross-sectional area (having the discrete header with an increased size of the partial header 170 , 170 ′, 170 ″) than a fuel cell stack comprising of 200 fuel cells, where both the fuel cell stack comprising of 300 fuel cells and the fuel cell stack comprising of 200 fuel cells use a common fuel cell plate and a common MEA. The fuel cell stack 110 , 110 ′, 110 ″ including the discrete header section 147 , 147 ′, 147 ″, 149 promotes proper and sustained alignment of the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 . During assembly of the fuel cell stack 110 , 110 ′, 110 ″ an assembly fixture or a guide is used to align the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 and MEAs 112 , 112 ′ that form the fuel cell stack 110 , 110 ′, 110 ″. The discrete header sections 147 , 147 ′, 147 ″, 149 are then secured to the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 according to one of the embodiments of the invention illustrated in FIGS. 2-4 , FIGS. 5-6 , and FIGS. 7-8 . The discrete header sections 147 , 147 ′, 147 ″, 149 militate against movement of the one of the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 and the MEAs 112 , 112 ′ in relation to the discrete header sections 147 , 147 ′, 147 ″, 149 . The fastening points 172 , 172 ′, 172 ″ of the discrete header sections 147 , 147 ′, 147 ″, 149 maintain contact with each of the fuel cell plates 114 , 120 , 120 ′, 120 ″, 122 and the MEAs 112 , 112 ′ to stabilize the fuel cell stack 110 , 110 ′, 110 ″. The fuel cell stack 110 , 110 ′, 110 ″ stabilized by the discrete header sections 147 , 147 ′, 147 ″, 149 militates against leakage of the reactants and the coolant that may occur as a result of the fuel cell stack 110 , 110 ′, 110 ″ shifting. Further, the fuel cell stack 110 , 110 ′, 110 ″ stabilized by the discrete header sections 147 , 147 ′, 147 ″, 149 militates against electrical shorting that may occur as a result of the fuel cell stack 110 , 110 ′, 110 ″ shifting.
A size of the partial headers 170 , 170 ′, 170 ″ may vary along the length of the discrete header sections 147 , 147 ′, 147 ″, 149 to control the cross-sectional area and the volume of the supply headers and the exhaust headers. The cross-sectional area of the supply headers and the exhaust headers that varies along the length of the discrete header sections 147 , 147 ′, 147 ″, 149 allows a pressure differential existing along the length of the supply headers and the exhaust headers to be minimized, affording substantially equal flow rates of the reactants and the coolant into and out of the fuel cells at any point along the length of the supply headers and the exhaust headers. Further, the inlet conduits 152 , 154 , 160 , 160 ′, 160 ″, the outlet conduits 156 , 158 , 162 , or other equipment may be incorporated into the discrete header sections 147 , 147 ′, 147 ″, 149 to simplify operation of the fuel cell system including the discrete header section 147 , 147 ′, 147 ″, 149 . As shown in FIGS. 2-8 , the coolant inlet conduit 160 , 160 ′, 160 ″ is integrally formed with the discrete header section 147 , 147 ′, 147 ″, eliminating the need for the inlet conduit formed in the clamping plate 118 . The supply inlet conduits 152 , 154 , 160 , 160 ′, 160 ″ the outlet conduits 156 , 158 , 162 , or other equipment incorporated into the discrete header section 147 , 147 ′, 147 ″, 149 permits greater design flexibility of the fuel cell stack 110 , 110 ′, 110 ″ and minimizes “crowding” that may occur in an end unit the supply inlet conduits 152 , 154 , 160 , 160 ′, 160 ″ the outlet conduits 156 , 158 , 162 , or other equipment is incorporated in. As a non-limiting example, the discrete header section 147 , 147 ′, 147 ″, 149 may include an ejector integrally formed with the discrete header section 147 , 147 ′, 147 ″, 149 , where the ejector is in fluid communication with an injector disposed in the end unit of the fuel cell system.
While certain representative embodiments and details have been shown for purposes of illustrating the invention, it will be apparent to those skilled in the art that various changes may be made without departing from the scope of the disclosure, which is further described in the following appended claims. | A fuel cell system comprises a main body including a first partial header and a fastening point. The main body is adapted to be coupled to a plurality of plates forming a fuel cell stack, allowing a single plate design to be used for multiple fuel cell stack lengths having a large differential of energy requirements, affording a durable alignment mechanism for the fuel cell stack, and providing integration flexibility for components and configurations of the fuel cell system. | 7 |
FIELD OF THE INVENTION
This invention relates generally to a development apparatus for ionographic or electrophotographic imaging and printing apparatuses and machines, and more particularly is directed to a toner transport using traveling wave potential waveforms for separation of opposite sign charged particles, but can be also applied in other machines and technologies which involve handling and/or separation of small charged particles.
INCORPORATED BY REFERENCE
The following is specifically incorporated by reference patent application, D/98522, U.S. Ser. No., 09/312,873, D/98523, U.S. Ser. No. 09 1312,872 and D199724, U.S. Ser. No. 09/145,837 entitled “A MULTIZONE METHOD FOR XEROGRAPHIC POWDER DEVELOPMENT: VOLTAGE SIGNAL APPROACH”, “A METHOD FOR LOADING DRY XEROGRAPHIC TONER ONTO A TRAVELING WAVE GRID”and “TONER TRANSPORT USING SUPERIMPOSED TRAVELING ELECTRIC POTENTIAL WAVES, respectively.
BACKGROUND OF THE INVENTION
Generally, the process of electrophotographic printing includes charging a photoconductive member to a substantially uniform potential so as to sensitize the surface thereof. The charged portion of the photoconductive surface is exposed to a light image from either a scanning laser beam or an original document being reproduced. This records an electrostatic latent image on the photoconductive surface. After the electrostatic latent image is recorded on the photoconductive surface, the latent image is developed. Two component and single component developer materials are commonly used for development. A typical two component developer comprises magnetic carrier granules having toner particles adhering triboelectrically thereto. A single component developer material typically comprises toner particles. Toner particles are attracted to the latent image forming a toner powder image on the photoconductive surface, the toner powder image is subsequently transferred to a copy sheet, and finally, the toner powder image is heated to permanently fuse it to the copy sheet in image configuration.
The electrophotographic marking process given above can be modified to produce color images. One color electrophotographic marking process, called image on image processing, superimposes toner powder images of different color toners onto the photoreceptor prior to the transfer of the composite toner powder image onto the substrate. While image on image process is beneficial, it has several problems. For example, when recharging the photoreceptor in preparation for creating another color toner powder image it is important to level the voltages between the previously toned and the untoned areas of the photoreceptor.
In the application of the toner to the latent electrostatic images contained on the charge-retentive surface, it is necessary to transport the toner from a developer housing to the surface. A limitation of conventional xerographic development systems, including both magnetic brush and single component, is the inability to deliver toner (i.e. charged pigment) to the latent images without creating large adhesive forces between the toner and the conveyor on which the toner rests and which transports the toner to latent images. As will be appreciated, large fluctuation in the adhesive forces that cause the pigment to tenaciously adhere to the carrier severely limits the sensitivity of the developer system thereby necessitating higher contrast voltages forming the images. Accordingly, it is desirable to reduce the large adhesion particularly in connection with latent images formed by contrasting voltages.
In order to minimize the adhesive forces, there is provided, in the preferred embodiment of the invention a toner conveyor including means for generating traveling electrostatic waves which can constantly move the toner about the surface of the conveyor with minimal static contact therewith.
Traveling waves have been employed for transporting toner particles in a development system, for example U.S. Pat. No. 4,647,179 to Schmidlin which is hereby incorporated by reference. In that patent, the traveling wave is generated by alternating voltages of three or more phases applied to a linear array of conductors placed abut the outer periphery of the conveyor. The force F for moving the toner about the conveyor is equal qE t where q is the charge on the toner and E t is the tangential field supplied by a multi-phase AC voltage applied to the array of conductors.
Traveling wave devices have been proposed for a number of years to transport, separate and deliver charged particles to a latent electrostatic image. Some of the other reasons this is an attractive approach include absence of moving mechanical parts, control of the toner position, long and stable development zones, and architectural flexibility. A semiconductive overcoat may be desirable on the grid providing a smooth surface for the toner motion and also a possible charge relaxation channel. It has been found that various modes of charged particle transport are possible. The so-called synchronous modes of the electrostatic traveling wave transport have been found and indicated as appropriate to facilitate the toner transport that can be used for xerographic development systems. In those modes, the toner particles move along the carrying surface with the traveling wave phase velocity v ph =ω/k where ω and k are the frequency and the wavevector of the wave respectively. This velocity is achieved through the action of the longitudinal (x) component of the electrostatic force while the normal (z) component of the force on the average contains the toners near the carrying surface.
In the other, so-called “curtain” or asynchronous mode, toners would be effectively repelled by the wave from the surface and could be retained only by an external force such as the gravity or an applied electric field. In the absence of the latter, the toners would be very loose and subject to emissions. Transport in this mode ordinarily occurs with velocities much lower than v ph .
SUMMARY OF THE INVENTION
There is provided an apparatus for developing a latent image recorded on an imaging surface, including a donor member, spaced from the imaging surface, for transporting toner on the surface thereof to a region opposed from the imaging surface, said donor member includes an electrode array on the outer surface thereof, said array including a plurality of spaced apart electrodes extending substantial across width of the surface of the donor member; loading toner onto said donor member; a multi-phase voltage source operatively coupled to said electrode array, said multiphase voltage source generating a waveform which creates an electrodynamic wave pattern for moving toner particles of one polarity to and from a development zone and preventing toner particles of the opposite polarity from moving on to said development zone.
An object of the present invention is to provide a novel class of electrostatic potential waveforms for traveling wave grids which will enable effective dynamic separation of charged particles of opposite signs as an additional functionality to their transport. This class comprises such waveforms that produce electrostatic potential reliefs with a special kind of either temporal or static asymmetry. With waveforms of the present invention, charged particles (e.g. toners) of opposite polarities are forced to exhibit very different dynamic responses, e.g., they can be transported in an unipolar synchronous mode (only species of one sign would be able to move with the wave phase velocity) or in an ambipolar bidirectional mode (particles of opposite signs move in opposite directions).
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-12 illustrate various driving waveforms and particle trajectories pertinent to the subject of the present invention and are described in more detail below.
FIGS. 13 — 16 show illustrative printing and development apparatuses:
FIG. 13 is a schematic elevational view of an illustrative electrophotographic printing or imaging machine or apparatus incorporating a development apparatus that can have the features of the present invention therein;
FIG. 14 is a schematic elevational view showing the development apparatus used in the FIG. 13 printing machine;
FIGS. 15 and 16 are top view of a portion of the flexible donor belt that can be used in the context of the present invention;
Inasmuch as the art of electrophotographic printing is well known, the various processing stations employed in the printing machine will be shown hereinafter schematically and their operation described briefly with reference thereto.
DETAILED DESCRIPTION OF THE INVENTION
Referring initially to FIG. 13, there is shown an illustrative electrophotographic machine having incorporated therein the development apparatus of the present invention. An electrophotographic printing machine creates a color image in a single pass through the machine and incorporates the features of the present invention. The printing machine uses a charge retentive surface in the form of an Active Matrix (AMAT) photoreceptor belt 10 which travels sequentially through various process stations in the direction indicated by the arrow 12 . Belt travel is brought about by mounting the belt about a drive roller 14 and two tension rollers 16 and 18 and then rotating the drive roller 14 via a drive motor 20 .
As the photoreceptor belt moves, each part of it passes through each of the subsequently described process stations. For convenience, a single section of the photoreceptor belt, referred to as the image area, is identified. The image area is that part of the photoreceptor belt which is to receive the toner powder images which, after being transferred to a substrate, produce the final image. While the photoreceptor belt may have numerous image areas, since each image area is processed in the same way, a description of the typical processing of one image area suffices to fully explain the operation of the printing machine.
As the photoreceptor belt 10 moves, the image area passes through a charging station A. At charging station A, a corona generating device, indicated generally by the reference numeral 22 , charges the image area to a relatively high and substantially uniform potential.
After passing through the charging station A, the now charged image area passes through a first exposure station B. At exposure station B, the charged image area is exposed to light which illuminates the image area with a light representation of a first color (say black) image. That light representation discharges some parts of the image area so as to create an electrostatic latent image. While the illustrated embodiment uses a laser based output scanning device 24 as a light source, it is to be understood that other light sources, for example an LED printbar, can also be used with the principles of the present invention
After passing through the first exposure station B, the now exposed image area passes through a first development station C which is identical in structure with development system E, G, and I. The first development station C deposits a first color, say black, of negatively charged toner 76 onto the image area. That toner is attracted to the less negative sections of the image area and repelled by the more negative sections. The result is a first toner powder image on the image area.
For the first development station C, development system 34 includes a flexible donor belt 42 having groups of electrode arrays near the surface of the belt which develops the image with toner.
After passing through the first development station C, the now exposed and toned image area passes to a first recharging station D. The recharging station D is comprised of two corona recharging devices, a first recharging device 36 and a second recharging device 37 , which act together to recharge the voltage levels of both the toned and untoned parts of the image area to a substantially uniform level. It is to be understood that power supplies are coupled to the first and second recharging devices 36 and 37 , and to any grid or other voltage control surface associated therewith, as required so that the necessary electrical inputs are available for the recharging devices to accomplish their task.
After being recharged by the first recharging device 36 , the image area passes to the second recharging device 37 .
After being recharged at the first recharging station D, the now substantially uniformly charged image area with its first toner powder image passes to a second exposure station 38 . Except for the fact that the second exposure station illuminates the image area with a light representation of a second color image (say yellow) to create a second electrostatic latent image, the second exposure station 38 is the same as the first exposure station B.
The image area then passes to a second development station E. Except for the fact that the second development station E contains a toner which is of a different color (yellow) than the toner (black) in the first development station C, the second development station is beneficially the same as the first development station. Since the toner is attracted to the less negative parts of the image area and repelled by the more negative parts, after passing through the second development station E the image area has first and second toner powder images which may overlap.
The image area then passes to a second recharging station F. The second recharging station F has first and second recharging devices, the devices 51 and 52 , respectively, which operate similar to the recharging devices 36 and 37 .
The now recharged image area then passes through a third exposure station 53 . Except for the fact that the third exposure station illuminates the image area with a light representation of a third color image (say magenta) so as to create a third electrostatic latent image, the third exposure station 38 is the same as the first and second exposure stations B and 38 . The third electrostatic latent image is then developed using a third color of toner (magenta) contained in a third development station G.
The now recharged image area then passes through a third recharging station H. The third recharging station includes a pair of corona recharge devices 61 and 62 which adjust the voltage level of both the toned and untoned parts of the image area to a substantially uniform level in a manner similar to the corona recharging devices 36 and 37 and recharging devices 51 and 52 .
After passing through the third recharging station the now recharged image area then passes through a fourth exposure station 63 . Except for the fact that the fourth exposure station illuminates the image area with a light representation of a fourth color image (say cyan) so as to create a fourth electrostatic latent image, the fourth exposure station 63 is the same as the first, second, and third exposure stations, the exposure stations B, 38 , and 53 , respectively. The fourth electrostatic latent image is then developed using a fourth color toner (cyan) contained in a fourth development station I.
To condition the toner for effective transfer to a substrate, the image area then passes to a pretransfer corotron member 50 which delivers corona charge to ensure that the toner particles are of the required charge level so as to ensure proper subsequent transfer.
After passing the corotron member 50 , the four toner powder images are transferred from the image area onto a support sheet 52 at transfer station J. It is to be understood that the support sheet is advanced to the transfer station in the direction 58 by a conventional sheet feeding apparatus which is not shown. The transfer station J includes a transfer corona device 54 which sprays positive ions onto the backside of sheet 52 . This causes the negatively charged toner powder images to move onto the support sheet 52 . The transfer station J also includes a detack corona device 56 which facilitates the removal of the support sheet 52 from the printing machine 8 .
After transfer, the support sheet 52 moves onto a conveyor (not shown) which advances that sheet to a fusing station K. The fusing station K includes a fuser assembly, indicated generally by the reference numeral 60 , which permanently affixes the transferred powder image to the support sheet 52 . Preferably, the fuser assembly 60 includes a heated fuser roller 62 and a backup or pressure roller 64 . When the support sheet 52 passes between the fuser roller 62 and the backup roller 64 the toner powder is permanently affixed to the sheet support 52 . After fusing, a chute, not shown, guides the support sheets 52 to a catch tray, also not shown, for removal by an operator.
After the support sheet 52 has separated from the photoreceptor belt 10 , residual toner particles on the image area are removed at cleaning station L via a cleaning brush contained in a housing 66 . The image area is then ready to begin a new marking cycle.
The various machine functions described above are generally managed and regulated by a controller which provides electrical command signals for controlling the operations described above.
Turning to FIG. 14, which illustrates the development system 34 in greater detail, development system 34 includes a housing 44 defining a chamber 76 for storing a supply of developer material therein. Donor belt 42 is mounted on stationary roll 41 and belt portion 43 is mounted adjacent to magnetic roll 46 . Donor belts 42 comprise a flexible circuit broad having finely spaced electrode array 200 thereon as shown in FIGS. 15 and 16. The typical spacing between electrodes is between 75 and 100 microns. The electrode array 200 has a four phase grid structure consisting of electrodes 202 , 204 , 206 and 208 having a voltage source and a wave generator 300 operatively connected thereto in the manner shown in order to supply the proper wave form in the appropriate electrode area groups A-E.
Electrode array 200 has group areas A-E in which each group area is individually addressable to perform the function of: (A) Loading toner onto the array from the housing; (B) Transferring toner to the development zone; (C) Developing the image in the development zone; (D) Transferring toner from the development zone and (E) Unloading toner from the array back into the housing. Each electrode array group area is independently addressable and operatively connected to voltage source 220 and wave generator 300 . The electrodes in array group area (A) picks up the toner from the housing and transports it via the electrostatic wave set up by wave generator 300 . Electrode array group areas A-E connected to the voltage source via wave generator 300 develops a traveling wave pattern is established. The electrostatic field forming the traveling wave pattern loads the toner particles from the developer sump 76 to the surface of the donor belt 42 and transports them along donor belt 42 to the development zone with the photoreceptor belt 10 where they are transferred to the latent electrostatic images on the belt 10 . Thereafter, the remaining (untransferred) toner is moved by electrode array group area D to electrode group area E where remaining toner is unloaded off the belt.
An important property of this type of transporting device, especially in the context of electrode group areas A and B, is the ability to classify toners, e.g., by tribo, i.e. their charge-to-mass ratio, q/m. For instance, for given frequency and amplitude of the wave, only toners charged higher than some critical value would be able to move synchronously with the wave (to “catch the wave”). Correspondingly, very low-tribo toners would not be delivered into the development zone. However, for toner supplies containing both positively and negatively charged particles, it is another question that becomes very important, i.e. whether an effective separation of species can be achieved based solely on the sign of their charge (positive vs. negative) rather than on the magnitude of this charge or other particle parameters. From the very nature of the idealized (basic) sinusoidal traveling wave, it is clear that such a wave would like to transport particles of either sign in the same direction (that of the running wave itself, although separated by a half wavelength from each other. Indeed, the electrostatic force arising from a sinusoidal wave is given by its components
F x =qE o exp(− kz )sin(φ), (1a)
F z =qE o exp(− kz )cos(φ) (1b)
where the phase φ=kx−ωt, E o the maximum field strength and q the particle charge. Evidently, the same distribution of the electrostatic forces would be seen by a particle of charge (−q) but positioned with respect to the wave with the phase shift π:φ→φ+π. In other words, particles of opposite signs would ride opposite sides of the potential hill of the wave. The same considerations can apply for practical grid designs with finite number of phase electrodes, as is, e.g., sketched in FIG. 1 for a 4-phase grid design utilizing a conventional pulsed waveform.
FIG. 1 . Schematically shown are potentials applied at different times of a conventional 50% duty cycle signal to electrodes of a 4-phase grid (displayed are 8 electrodes corresponding to two wavelengths of the structure). Circles symbolize positions of different charged particles right at the moment when the potential pattern indicated is switched on. Responding to a new distribution of electric fields, particles “move” to a new position shown at the next time step. Clear circle symbols are for positive particles and black circle ones are for negative. T is the period of the signal. We chose to schematically show the particles in between the electrodes (where the longitudinal forces are effective). The simplistic picture of synchronous transport displayed in FIG. 1 is corroborated by dynamical simulations as well as experimentally. Obviously, positive and negative particles here are transported in the same direction.
FIG. 2 . The corresponding voltage pattern driving the electrodes of this grid during one period T For clarity, the voltage profiles for different electrodes are displaced vertically—the lower and upper values of the potential pattern are in fact the same for all electrodes.
The situation with practical grids employing various temporal waveforms is more complex than that with the idealized sinusoidal wave. An arbitrary potential waveform for an n-phase grid structure can be written as
U ( m x,t )=Σ i=1 n g i ( t )f i ( X ) (2)
where g i and f i represent the temporal (periodic with period T) and spatial (periodic with period λ) contributions from the λ electrode. The hardware grid design defines usually f i (x)=f(x−λ/n) where λ is the structure wavelength—all electrodes are the same. It is the temporal waveform g i (t) that can be judiciously designed to achieve the separation purpose of the present invention. At each moment of time t, the potential relief (2) can be thought of as a periodically repeated potential hill structure. FIG. 1, e.g., gives a clear visualization of such a picture. The derivatives of the potential hill yield the fields acting on charged particles. Evidently opposite sides of the potential hill there are effectively responsible for a coherent interaction with oppositely charged particles respectively. The electrostatic picture of FIG. 1 possesses two important properties: firstly, the potential hill is symmetric with respect to a mirror reflection, and secondly, its time evolution corresponds essentially to translations along the wave propagation direction (preservation of shape). Whenever these two properties are in place (the latter, in general, with some accuracy caused by the discrete electrode structure), one should expect a similar transport pattern for both positive and negative charges. More precisely, dynamical simulations show that details of transport can sometimes differ for species of opposite signs but an overall average effect generally turns out to be the same.
To make synchronous transport for species of one sign prohibited, we propose to use waveforms that sufficiently strongly violate either of the two potential properties mentioned above. That is, e.g., the potential hill can be made strongly asymmetric statically, or, otherwise, its overall temporal evolution can be made more complex than a mere translation asymmetrically affecting potential hill's slopes. In what follows we give examples of such waveforms.
In the first example, illustrated in FIGS. 3 and 4, we temporally modulate the waveform in such a way that one side of the potential hill regularly translates with time (so that the particles riding this side can adjust their positions with respect to the wave) while the other side's relative position “fluctuates” (so that the particles that would otherwise ride this side have no time to adjust, fall “out-of-phase ” and lose the wave; in practical conditions these particles would probably not load onto the grid at all.
FIG. 3 . Using the same notation as FIG. 1, the potential patterns and their effect on charged particles are shown for the case where the waveform alternates between 50% and 25% duty cycle with the frequency twice as high as the main frequency.
FIG. 4 . The corresponding voltage pattern driving the electrodes of this grid during one period T The same vertical displacement of voltage profiles for different electrodes as in FIG. 2 .
As the simplistic picture of FIG. 3 suggests, the positive charges there are capable of synchronously moving with the wave while the negative charges cannot catch the wave (compare with FIG. 1 ). Dynamical simulations confirm this insight and show that the negative charges in this case are lifted from the carrying surface and could continue their transport but already only in the asynchronous curtain mode. The same method of waveform alternations works as well for 3-phase grids and other grid designs. As can be seen in FIG. 3, the potential drop used by the positive particle retains its relative position with respect to the wave, the negative charge, on the other hand, cannot see a “consistent” propelling force pattern.
In the second example, we use the facts that a modulated waveform can be made 'commensurable” with the wavelength and that opposite sides of the potential hill made act “coherently”, to devise waveforms whose effects on particles of opposite signs would be even more “opposite ”. The potential waveform shown in FIG. 5 differs from that in FIG. 3 by modified potentials of the electrodes at t=0.25T and t=0.75T so that momentarily the pattern looks as having the spatial period twice as small. The effect on transport turns out to be drastic: the species of opposite signs can now be transported in opposite directions.
FIG. 5 . Schematics of a modulated waveform that facilitates transport of opposite sign particles in opposite directions.
FIG. 6 . The corresponding voltage pattern driving the electrodes of this grid during one period T The same vertical displacement of voltage profiles for different electrodes as in FIG. 2 .
Again, simplistic considerations illustrated in FIG. 5 are confirmed by dynamic simulations. FIGS. 7A, 7 B and FIGS. 8A, 8 B show trajectories of a positive and a negative particle, respectively, induced by the waveform of FIG. 5 . Evidently from FIGS. 7A, 7 B and FIGS. 8A, 8 B, particles of opposite signs indeed move in opposite directions in a hopping synchronous mode. The effect has been confirmed experimentally as well.
In the third example, we use such a waveform that produces a strongly asymmetric potential hill structure that regularly translates with time along the wave propagation. Therefore electric fields in one direction turn out to be much stronger than in the opposite direction (although on a larger scale). With asymmetry strong enough, the particles that would otherwise ride the less steeper side of the hill cannot catch the traveling wave and are repelled by the wave away from the carrying surface. They are then either lost to emissions or transported in the curtain mode with the velocity much lower than the wave phase velocity. The discussed waveforms can therefore provide transport in the unipolar synchronous mode, similarly to the situation discussed in the first example FIGS. 9 and 10 schematically show an example of such a waveform.
This waveform as seen by individual electrodes corresponds to the ramp-type driving voltage as shown in FIG. 10 (or its pulsed counterpart, and, of course, with appropriate phase shifts for different electrodes Evidently, the electric field moving a positive particle in this example is about three times stronger in this case than the field that would move a negative particle in the wave's direction. The negative particle is displayed as being lost while the positive particle moves with the wave phase velocity
The results of dynamical simulations using this type of waveform for positive and negative particles are shown in FIGS. 11 and 12.
As seen in FIGS. 11A, 11 B the electric field strength turns out to be sufficient to balance air drag and surface friction for the positive particle and it catches the wave. The electric field relevant for the negative particle is not high enough and the particle is repelled away from the surface to be lost by the wave, as displayed in FIGS. 12A and 12B.
The examples above have been intended to illustrate how the general principles of the present invention can be implemented. Evidently, many other implementations are possible that would use these general principles and also lead to different dynamic responses for oppositely charged particles. Other embodiments and modifications of the present invention may occur to those skilled in the art subsequent to a review of the information presented herein; these embodiments and modifications, as well as equivalents thereof, are also included within the scope of this invention. | An apparatus for developing a latent image recorded on an imaging surface, including a donor member, spaced from the imaging surface, for transporting toner on the surface thereof to a region opposed from the imaging surface, the donor member includes an electrode array on the outer surface thereof, the array including a plurality of spaced apart electrodes extending substantial across width of the surface of the donor member; loading toner onto the donor member; a multi-phase voltage source operatively coupled to the electrode array, the multiphase voltage source generating a waveform which creates an electrodynamic wave pattern for moving toner particles of one polarity to and from a development zone and preventing toner particles of the opposite polarity from moving on to the development zone. | 6 |
TECHNICAL FIELD
The present invention generally relates to the field of data processing. More particularly, and without limitation, the invention relates to data processing in the field of user authorization.
BACKGROUND INFORMATION
A user's right to read and write specific data objects stored in a data processing system may be specified in his or her user profile. Manual maintenance of such user profiles is a tedious and error prone task. For example, if an organizational structure of a company changes, the respective user authorizations also need to be changed. This may require a manual update of a large number of user profiles that are afflicted by the organizational change.
Structural user authorization is a concept that aims to reduce this drawback. For example, SAP's authorization system as implemented in SAP R/3 (commercially available from SAP AG, Walldorf, Germany) has a structural authorization concept, as described in SAP Authorization System—Design and Implementation of Authorization concepts for SAP R/3 and SAP Enterprise Portals, IBM Business Consulting GmbH, SAP Press (see Chapter 2.3.5, page 52).
SUMMARY
In accordance with embodiments of the present invention, data processing systems may be provided that include means for storing first data descriptive of at least one directed acyclic graph and for storing second data descriptive of an assignment of a user to a first node of the graph. The data processing systems may also include means for receiving an access request of the user, the access request specifying a second node of the graph. Furthermore, the data processing systems may include means for determining a least common ancestor of the first and second nodes of the graph, and means for performing an authorization check to grant authorization for the access request if the least common ancestor of the first and second nodes is the first node.
In one embodiment consistent with the invention, the nodes of the graph may be assigned to data objects. The access request of the user may explicitly specify the second node. Alternatively or in addition, the access request may implicitly specify the second node by indicating the data object to which access is requested.
For example, assume that the data objects are confidential. Read and/or write access to these data objects may be controlled by performing an authorization check for the respective user access request. In this manner, unauthorized access to confidential information may be prevented and access to such confidential information may only be granted to users that have the required access rights, as specified by the assignment of the users to first nodes in the graph.
The determination of the least common ancestor of the first and second nodes in the graph may be performed using any known algorithm for finding such ancestors. One example of such an algorithm is disclosed by Dov Harel and Robert Endre Tarjan in “Fast Algorithms for Finding Nearest Common Ancestors,” SIAM Journal on Computing, v.13 n.2, pp. 338-355, May 1984.
An algorithm that reduces the least common ancestor problem to the range minimum query problem may be used for determining the least common ancestor. An example of such an algorithm is described in M. A. Bender and M. Farach-Colton, “The LCA problem revisited,” Latin American Theoretical Informatics, pp. 88-94, Apr. 2000. For example, the sparse table algorithm for the range minimum query problem, described in the Bender, Farach-Colton reference, may be used for determining the least common ancestor of the first and second nodes. The above-noted Harl, Tarjan and Bender, Farach-Colton references are expressly incorporated herein by reference to their entireties.
In accordance with an embodiment of the invention, a least common ancestor (LCA) index may be pre-computed, such as in the form of one or more tables or a sparse table (e.g., using one of the algorithms disclosed in the Bender, Farach-Colton reference). In accordance with another embodiment of the invention, the pre-computed LCA index may be stored in shared memory in order to enable parallel processing of authorization checks for multiple access requests received from various users. When users send access requests at a high frequency, such as when the data processing system is used in a large organization or corporation, storage of the LCA index in shared memory, such as in an application server computer, can provide short latency times to users for the performance of the authorization check.
In accordance with an embodiment of the invention, the graph may be a tree and the nodes of the tree may represent organizational entities. For example, the root node of the tree may represent a company holding various subsidiaries and affiliated companies that are represented by lower level nodes of the tree. Each subsidiary or affiliated company may have various business units that are also represented by nodes of the tree. The business units may have various departments whereby each department is represented by a node of the tree. In other words, all organizational entities of a complex company holding structure may be represented by respective nodes of the tree.
The level of granularity of the tree may depend on the required level of granularity of the access control. For example, the tree may go down to the individual employee level to represent each individual employee by a node in the tree. This can be required if, for example, personnel records of the employees are of a confidential nature and, therefore, need to be access-protected.
In accordance with another embodiment of the invention, the tree may represent organizational entities but not individuals, thus preventing frequent updates of the tree. Although the organizational structure of a company may be changed infrequently, the job positions of individual employees may change more frequently due to promotions within the company, employee fluctuation, and employee attrition. If access control needs to be provided on an individual employee level, each employee may be assigned to a node of the tree that represents the organizational entity to which the employee currently belongs. If the employee changes his job position, but the organizational structure of the company remains unchanged, then the employee's assignment to one of the nodes of the tree may be updated, but the tree may remain unchanged. In this manner, the LCA index for the tree may not need to be re-computed.
In additional embodiments consistent with the invention, methods are provided for performing an authorization check for a user. The user may be assigned to a first node of a directed acyclic graph, and the methods may include receiving an access request from the user, the access request specifying a second node of the graph. Further, such methods may include determining a least common ancestor of the first and second nodes and granting authorization if the least common ancestor of the first and second nodes is the first node.
In accordance with an embodiment of the invention, the least common ancestor of the first and second nodes may be determined using a pre-computed LCA index. By using a pre-computed LCA index, latency times experienced by users for the performance of an authorization check may be reduced. In accordance with an embodiment of the invention, the pre-computation of the LCA index may be initialized in response to an access request if no previously pre-computed LCA index exists in shared memory or if the available LCA index is older than a predefined time limit.
In accordance with an embodiment of the invention, pre-computation of a new LCA index may be initiated if the tree has been updated after a preceding pre-computation of the newest available LCA index.
In accordance with an embodiment of the invention, each LCA index stored in shared memory may have one of a first, second, third, or fourth status. The first status may indicate that the LCA index can currently be used for determining least common ancestors of first and second nodes for the performance of respective authorization checks. The second status may indicate that the LCA index is “outdated.” An outdated LCA index may include a timestamp that indicates when the LCA index was put in the second “outdated” status. The outdated LCA index may be used for performing authorization checks if, for example, no current LCA index is available and if the outdated LCA index is not to old (e.g., if it is not older than a predefined first time interval). An exemplary first time interval is between five and fifteen minutes, such as ten minutes.
An LCA index may transition from the first to the second status if a pre-computation of the LCA index is initialized. The “outdated” LCA index may be used during the pre-computation for the performance of the authorization checks during the first time interval.
If neither a LCA index having the first status nor a LCA index having the second status is available, pre-computation of a new LCA index may be initiated asynchronously. The initialization of the pre-computation of the new LCA index may be performed by generating an instance of the LCA index that is initially empty. The instance of the LCA index may have a third status “wait.” During the third status the pre-computation may be delayed for a second time interval. The second time interval may be shorter than the first time interval. For example, the length of the second time interval may be approximately 10% to 30% of the first time interval.
The status of the instance may transition from the third status to a fourth status after the second time interval has lapsed. The fourth status may indicate that the pre-computation of the LCA index is “in progress.”
If there is neither an LCA index having the first status nor an LCA index having the second status, the authorization check may be performed without an LCA index using another technique, such as upwards traversal of the tree. In this manner, the latency time may be reduced when a LCA index does not exist or when the LCA index is not sufficiently up-to-date because the authorization check can be executed using an alternative algorithm, without having to wait until completion of the LCA index calculation.
In accordance with an embodiment of the invention, the second time interval of the instance having the third status may be incremented when a request for LCA pre-computation is made while the instance is still in its third status. This may increase the likelihood that all changes to the tree have been entered before the pre-computation of the LCA index starts. In this example, an additional instance for the LCA pre-computation may not be generated. For example, the second time interval may be incremented by restarting the second time interval or by adding an incremental time interval, such as one to three minutes.
In accordance with an embodiment of the invention, the status transition from the first status to the second status of the LCA index may be executed upon making a request for LCA pre-computation. The current LCA index that has the first status may be time stamped and placed in the second “outdated” status for temporary use during the first time interval while calculating the new LCA index.
In accordance with another embodiment of the invention, an instance of the LCA index that has the fourth status may be deleted upon receipt of a request for the LCA pre-computation while the instance is still in its fourth status, e.g., while computing the LCA index. The LCA index computation may be aborted due to the renewed LCA pre-computation request and the LCA pre-computation may be initiated again on the basis of the modified tree information.
Embodiments of the present invention may reduce the time and effort required for updating user profile information regarding user authorizations while minimizing the processing load for performing authorization checks. Further, authorization checks may be performed on the basis of relatively up-to-date tree information whereby the acceptable time interval during which an outdated LCA index can still be used may be selectable.
In still other embodiments consistent with the invention, computer program products may be provided for performing methods consistent with the present invention. The computer program products may be executed by an application server that generates the LCA indices on the basis of tree information stored in a database server.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention. In the drawings:
FIG. 1 illustrates, consistent with an embodiment of the invention, a block diagram of an exemplary data processing system;
FIG. 2 illustrates, consistent with an embodiment of the invention, a flowchart of an exemplary method;
FIG. 3 illustrates, consistent with an embodiment of the invention, an exemplary tree structure;
FIG. 4 illustrates, consistent with an embodiment of the invention, a block diagram of another exemplary data processing system;
FIG. 5 illustrates, consistent with an embodiment of the invention, a flowchart of another exemplary method; and
FIG. 6 illustrates, consistent with an embodiment of the invention, a flowchart of another exemplary method.
DETAILED DESCRIPTION
Reference will now be made in detail to embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
FIG. 1 illustrates an exemplary data processing system 100 . Data processing system 100 may include at least one database server 102 for storing user profiles 104 , one or more database tables 106 for storing data descriptive of the nodes and vertices of at least one directed acyclic graph, such as a tree, and data objects 108 , such as data files or other data structures.
Each node of the tree may be identified by a node identifier (ID) in database table 106 . User profiles 104 may reference these node IDs. For example, the user having user identifier (ID) “A” may be assigned to node ID “2”, whereas the user having user ID “B” may be assigned to the node having node ID “3”, etc. The assignment of users to nodes of the tree may specify authorization levels of the users. A single assignment of a node ID per tree may be sufficient to specify a user's authorization level.
Data objects 108 may also reference node IDs of the tree. A user that is assigned to a specific node of the tree may be allowed access to all data objects that are assigned to that node and all data objects assigned to lower tree nodes below the node specified for that user.
An application server 110 may be coupled to the database server 102 . Application server 110 and database server 102 may be closely or loosely coupled via the network 112 .
Application server 110 may include a shared memory 114 for multiple client computers 116 , 118 , . . . , that may be coupled to application server 110 by network 112 . Application server 110 may execute program instructions 120 for pre-computation of an LCA index 122 . Pre-computed LCA index 122 may be stored in shared memory 114 .
The LCA index pre-computation may be performed by any suitable LCA index pre-computation algorithm. For example, the LCA index may be calculated as one or more look up tables or a sparse table in accordance with one or more of the algorithms disclosed in the above-cited Bender, Farach-Colton reference. Application server 110 may access the required tree information stored in the database table 106 for the pre-computation of the LCA index.
Further, application server 110 may include program instructions 124 for performing an access authorization check. Program instructions 124 may be configured to read user profile information from user profiles 104 , using, for example, the node ID that is assigned to a given user. Program instructions 124 may also perform a LCA Index Lookup 128 of the LCA index 122 using the node ID obtained from the user profiles 104 and the node ID of another node of the tree that is specified in an access request 130 received from a client computer 116 , 118 . Application server 110 may also include program instructions for performing database access operations 132 for reading data from database server 102 .
In operation, application server 110 may execute program instructions 120 for computation of LCA index 122 , which may be stored in shared memory 114 . Program instructions 120 may be invoked automatically, such as by instructions 132 , if a modification of the tree is entered into the database table 106 .
Assume, without restriction, that user A logs onto client computer 116 and that user B logs onto client computer 118 . An access request 130 initiated by user A may identify user A and a data object to which user A requests read and/or write access. The specification of the data object may be explicit, such as by including access path information to that data object in the access request 130 . Alternatively, or in addition, access request 130 may indicate the node ID to which the data object of interest is assigned.
Receipt of access request 130 by application server 110 may invoke execution of program instructions 124 . Program instructions 126 may perform a lookup operation of user profiles 104 to read the node ID that is assigned to the user ID in the access request 130 . If the access request 130 does not directly specify a node ID of the tree to which access is requested, but rather specifies one of the data objects 108 , the node ID that is assigned to that data object 108 may also be read from database server 102 .
Next, program instructions 128 may be invoked to lookup the LCA index 122 using the node ID assigned to the user ID specified in the access request 130 . Program instructions 128 may also lookup the node ID assigned to data object 108 to which access is requested. Authorization may be granted for the access request 130 if the least common ancestor of the node that is assigned to the specified user and the node that is assigned to data object 108 of interest is the node that is assigned to the specified user. Accordingly, the requested read and/or write access operation may executed by program instructions 132 . However, if the contrary is the case, access request 130 may be rejected.
FIG. 2 illustrates, consistent with an embodiment of the invention, a flowchart illustrating an exemplary method. In step 200 , an access request may be received from one of the users. The access request may directly or indirectly specify the node n of a tree to which the data of interest is assigned. In step 202 , node u, to which the requesting user is assigned, may be looked up from the user profile of that user. Node u may specify the user's level of access authorization.
In step 204 , an LCA index look up may be performed for nodes n and u. The table entries obtained for the nodes n and u from the LCA index may be evaluated in step 206 to determine whether the least common ancestor of nodes u and n is node u. If not, access may be denied (step 208 ). If this condition is fulfilled, access may be authorized (step 210 ).
FIG. 3 illustrates, consistent with an embodiment of the invention, an exemplary tree 334 . Tree 334 has a root with node ID “1” and three tree levels 336 , 338 , and 340 . Tree level 336 has child nodes 2 and 3 of root node 1 . Tree level 338 has child nodes 4 , 5 , and 6 of node 2 and child node 7 of node 3 . Tree level 340 has child nodes 8 and 9 of node 6 .
In the exemplary user profile 104 of FIG. 1 , user A is assigned to node 2 . Accordingly, user A may have access rights to data objects assigned to node 2 and all nodes below node 2 , i.e., nodes that are connected to node 2 and that are on lower tree levels 338 and 340 . With reference to FIG. 3 , these nodes are nodes 4 , 5 , 6 , 8 , and 9 . Likewise, node 3 is assigned to user B such that user B has access rights to data objects assigned to node 3 and nodes below node 3 , i.e., node 7 .
For example, user A has access rights to the data object x that is assigned to node 2 . User A also has access rights to data object z (assigned to node 8 ) because node 8 is on a lower tree level, i.e., tree level 340 and because there is a tree path from node 2 to node 8 . However, user A does not have access rights to data object y as this is assigned to node 3 and node 3 is on the same tree level 336 as node 2 . In other words, the least common ancestor of nodes 2 and 3 is node 1 rather than node 2 . Therefore, the condition is not fulfilled and no access can be granted to user A for access to data object y.
FIG. 4 illustrates, consistent with embodiments of the invention, a block diagram of another exemplary data processing system 400 . Database server 402 may include a mapping table 442 that maps individuals, such as employees, to nodes of the tree, e.g., tree 334 , as stored in database table 406 . In this embodiment, tree 334 does not need to go down to the employee level; rather, tree 334 may only cover the organizational structure of the company, including all organizational entities except individual employees and/or individual jobs of an organizational entity. In this manner, pre-computed LCA index 422 does not need to be re-computed each time an employee fluctuation occurs and/or if new jobs are defined or abolished within one of the organizational entities modelled by tree 334 . Because changes in the organizational structure of a company may occur relatively infrequently, respective recalculations of the LCA index 422 may also be relatively infrequent.
In the example of FIG. 4 , employee “Smith” and employee “Miller” are assigned to node 8 of tree 334 . For example, the data object z that is also assigned to node 8 may be the personnel record of employee “Smith.”
LCA index 422 has a first status “current,” indicating LCA index 422 is currently to be used for authorization checks. In addition, or alternatively, an LCA index 444 may be stored in shared memory 414 . LCA index 444 has a second status “outdated” and a time stamp which indicates when the LCA index 444 transitioned from the first status “current” to its second status “outdated.” LCA index 444 can be used for current authorization checks if LCA index 422 is not available and if LCA index 442 is not too old, e.g. if a predetermined first time interval from the time stamp has not lapsed.
Shared memory 414 may also include an instance 446 of a new LCA index yet to be computed. Instance 446 has a third status “waiting,” which means the pre-computation of the new LCA index is delayed for a second time interval from the creation of the instance 446 .
Shared memory 414 may also include an instance 448 for the pre-computation of a new LCA index. Instance 448 has a fourth status “in progress,” which may indicate that the new LCA index is being pre-computed after the second time interval has lapsed.
Instructions 424 may include additional instructions 450 for performing an authorization check using an alternative method that does not require an LCA index. Instructions 450 may be executed if an authorization check needs to be performed at a time when neither a current LCA index nor an outdated LCA index for which the first time interval did not yet lapse is available.
FIG. 5 illustrates, consistent with the invention, a flowchart of an exemplary method of status-dependent use of LCA indices 422 and 444 ( FIG. 4 ). In step 500 , an authorization check may be initiated upon receipt of access request 430 by application server 410 . In step 502 , a determination may be made whether an LCA index having the first status “current” is available in shared memory 414 . In this example, LCA index 422 may be identified and used to perform the authorization check (step 504 ). Performance of the authorization check can be implemented in accordance with the steps 202 to 210 ( FIG. 2 ).
If there is no LCA index 422 in shared memory 414 , step 506 may be executed. There may not be an LCA index if, for example, a tree update had been entered into the database table 406 such that the current LCA index transitioned to outdated.
In step 506 , a determination is made whether an LCA index having the second status is in shared memory 414 and, if so, whether the second time interval of that LCA index has already expired. In this example, LCA index 444 may be identified as outdated. If the LCA index 444 is available in the shared memory 414 and if the second time interval has not yet expired, control may proceed to step 504 . In other words, the outdated LCA index 444 may be used to perform the authorization check because only a negligible amount of time has expired from its transition from the first to the second status. The second time interval may be configured depending on the particular application. For example, the second time interval can be between five to fifteen minutes, such as ten minutes.
If LCA index 444 does not exist or if the second time interval has lapsed, control may proceed to step 508 . In step 508 , a pre-computation of a new LCA index may be initiated. The pre-computation of the new LCA index may be performed asynchronously such that the subsequent step 510 can be carried out immediately after initialization of the pre-computation of the new LCA index (step 508 ).
In step 510 , instructions 450 ( FIG. 4 ) may be invoked to perform the authorization check without an LCA index. For example, the authorization check may be performed by upwards traversal of the directed graph, e.g., tree 334 .
FIG. 6 illustrates a flowchart of an exemplary method of LCA index pre-computation. In step 600 , program instructions 420 may be invoked due to the initialization of the LCA pre-computation in step 508 ( FIG. 5 ). In step 602 , a determination may be made whether an LCA index 446 exists in shared memory 414 . If so, control may proceed to step 604 .
In step 604 , the second time interval may be incremented for a period of time that is shorter than the first time interval. For example, if the first time interval is ten minutes, the second time interval may be incremented by two minutes. Pre-computation of the new LCA index may be executed after the incremented second time interval has lapsed.
If there is no LCA index 446 (status “waiting”) in shared memory 414 , a determination may be made in step 606 whether there is an LCA index 422 (current) in shared memory 414 . If an LCA index 422 (current) exists in shared memory 414 (step 606 ), control may proceed to step 608 where a determination may be made whether there is an LCA index 444 (outdated/timestamp) in shared memory 414 .
If an LCA index 444 exists, LCA index 422 may transition from its first status to the second status and may be time stamped in order to become LCA index 444 (step 610 ). If, however, LCA index 444 exists in shared memory 414 , LCA index 444 may be deleted and the status transition of the LCA index 422 may be executed from its first status to the second status such that the LCA index 422 replaces the former LCA index 444 (step 612 ). From steps 610 or 612 , control may proceed to step 614 (described below).
Returning to step 606 , if a determination is made that there is no LCA index 444 does not exists in shared memory 414 , control may proceed to step 624 . In step 624 , a determination may be made whether there is an instance 448 (status “in progress”) in shared memory 414 . If such an instance 448 exists, control may proceed to step 626 where the ongoing pre-computation of the LCA index with respect to the existing instance 448 may be stopped and instance 448 may be deleted. Control may then proceed to step 614 . If, however, step 624 determines that instance 448 does not exist in shared memory 414 , control may proceed directly to step 614 .
At step 614 , the instance 446 for a new LCA index may be generated and the status set to “waiting”. After the second time interval has lapsed (e.g., two minutes, step 616 ), LCA index 446 may transition to instance 448 (status “in progress,” step 618 ) and the new LCA index may be computed in step 620 . After completion of the new LCA index, instance 448 may transition to become the new LCA index 422 (status changed from “in progress” to “current,” step 622 ).
Systems and methods consistent with the present invention, including those disclosed herein, may be embodied in various forms including, for example, a data processor, such as a computer that also includes a database, digital electronic circuitry, firmware, software, or in combinations thereof. Moreover, the above-noted features and other aspects and principles of the present invention may be implemented in various environments.
Such environments and related applications may be specially constructed for performing the various processes and operations according to the invention or they may include a general-purpose computer or computing platform selectively activated or reconfigured by code to provide the necessary functionality. The processes disclosed herein are not inherently related to any particular computer, network, architecture, environment, or other apparatus, and may be implemented by a suitable combination of hardware, software, and/or firmware. For example, various general-purpose machines may be used with programs written in accordance with teachings of the invention, or it may be more convenient to construct a specialized apparatus or system to perform the required methods and techniques.
Embodiments of the invention may be implemented as a computer program product, i.e., a computer program tangibly embodied in an information carrier, e.g., in a machine readable storage device or in a propagated signal, for execution by, or to control the operation of, data processing apparatus, e.g., a programmable processor, a computer, or multiple computers. A computer program can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments and features of the invention disclosed herein. It is intended, therefore, that the specification and embodiments be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. | Systems, methods, and computer program products are provided for performing an authorization check for a user. In one implementation, a data processing system is provided that includes means for storing first data descriptive of at least one directed acyclic graph and for storing second data descriptive of an assignment of a user to a first node of the graph. The data processing system also includes means for receiving an access request of the user, the access request specifying a second node of the graph. Furthermore, the data processing system includes means for determining a least common ancestor of the first and second nodes of the graph and means for performing an authorization check adapted to grant authorization for the access request if the least common ancestor of the first and second nodes is the first node. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a U.S. National Phase of the PCT International Application No. PCT/EP2008/058073, filed Jun. 25, 2008 and published as WO 2009/000851 on Dec. 31, 2008, which claims priority to European Application No. 07111204.9, filed Jun. 27, 2007. The disclosure of both prior applications is incorporated by reference in their entirety and should be considered a part of this specification.
FIELD OF THE INVENTION
The present invention relates to threaded joints, in particular for connecting tubes to create strings used in the hydrocarbon industry especially for use in the field of OCTG (Oil Country Tubular Goods) and pipelines in offshore applications.
BACKGROUND OF THE INVENTION
Searching for oil or, more generally, hydrocarbons has become more demanding in terms of hardware and devices in recent years because oil and gas fields or reservoirs are located deeper or in places difficult to reach and below the sea. Prospecting for and exploitation of hydrocarbon fields demands hardware which is more resistant to environmental challenges such as higher loads and corrosion, which were less important previously.
In some applications threaded joints can be subject to deformation of the joint seals.
Modern joints are generally designed with metal to metal seals made by the contact between two surfaces, usually at one end or at both ends of the threaded portion of the joint, interfering in the elastic range of the modulus of elasticity for an appropriate stress magnitude. However there are situations where resilient seals are needed instead of or in combination with metal seals, to prevent penetration of external fluids into the interstices of the threads.
It is therefore a design requirement that the joint seals resist penetration of external or internal fluids, or at least do not allow continuous exchange of fluids that have already penetrated the joint with surrounding fluids, in order to reduce the corrosion rate.
Currently a widespread technical solution to the problem of externally sealing a threaded connection is to use O-rings or resilient seal rings of various cross-sections, made of elastomeric or composite materials.
Complex resilient seal rings and simple O-rings perform their sealing function based on the diametrical geometric interference between pin and box, which is predefined with respect to at least one of the joint members. Said geometric interference appears after make up of the connection, to elastically deform the seal ring and thus induce contact pressures between the seal and each of the pin and box, defining a mechanical barrier which seals the joint. An additional energization of the seal ring is provided by the external fluid pressure which increases deformation and adherence to the seat where the seal ring is housed.
An example of an O-ring is disclosed in U.S. Pat. No. 6,173,968 for sealing a joint between a pin and box. An O-ring abuts an annular backup ring of substantially the same diameter. The annular backup ring is split to permit radial expansion and has a greater thickness on its outer periphery than on its inner periphery. When the joint being sealed is under high pressure, the seal ring urges the backup ring to expand radially to cover any gap between the members being sealed, maintaining sealing capacity, even under high temperature conditions, and preventing the sealing ring from extruding into the gap. The pressure varies with sea depth and seal efficiency is reduced when lower pressures act on the O-ring.
In this document the external pressure on the joint determines also the pressure acting on the O-ring. When higher contact pressures are needed for the O-ring, then higher geometric interference is required between the O-ring and joint members. This might cause seal breakage.
Another way to improve efficiency of the sealing capacity of the O-ring is by increasing geometric interference, which is achieved in most cases by making the seal ring radially bigger than its housing. However, the bigger the seal ring, the more exposed is it to damage during make up, especially when it is pre-mounted in the box member and it is forced to overcome the entire pin threaded area.
In this case other drawbacks may arise. Several geometric connection variables that originate during the manufacturing process, such as ovality, eccentricity, and rugosity, introduce uneven interference over the whole circumference of the sealing surfaces, thus producing uneven contact pressures and reducing the sealing capacity.
In practice, sealing capacity due to geometric interference is limited by the geometry, mainly radial sizes and length, of resilient elements in relation to their ability to be dragged during make up across the threads and any other interfering surface without being damaged.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a threaded joint which overcomes the aforementioned drawbacks.
The principal object of the present invention is to provide a joint having an innovative seal ring ensuring both simple and reliable initial make-up and a high sealing efficiency during operation.
The above mentioned objects are achieved in accordance with the present invention by means of a threaded tube joint defining an axis comprising a male threaded tube, defined as a pin, and a female threaded tube, defined as a box, the pin being adapted to be made up in the box. A seal ring has an external cylindrical surface, an internal surface comprising one or more annular ribs protruding from the internal surface, a first base with at least a portion of a frustoconical shape, a second base with at least a portion of a frustoconical shape axially opposite to the first base. The first and second bases are slanted towards the axis whereby the external surface is wider than the internal surface. The seal ring is interposed between the pin and the box in tight sealing contact with an internal surface of an annular groove of the box by the external cylindrical surface and in tight sealing contact with an external surface of the pin by the annular ribs. Hydraulic actuating means can pressurize the seal ring against said pin to provide improved scalability of the joint.
In the threaded joint of the invention the seal ring is housed within the box member, and is actuated and energized by means of the pressurization of an external injected fluid, injection and pressurization of this fluid being effected via a non-return valve, fixed to the box member.
The housing for the seal ring is an annular groove formed in the box member of the threaded joint. It houses and protects the seal ring against shocks before it is activated by the pressurizing fluid. This housing is configured to provide a fluid tight cavity embracing the seal ring and allowing its energization.
The box of the threaded joint incorporating this seal is made in such a way that the seal ring actuates on a cylindrical surface, advantageously that of the tube body, and thus the pin does not need to be modified. In this manner the joint's performance under tension loads remains intact.
Both the annular groove, non-return valve and seal ring are completely contained within the box wall thickness, this having the advantage of preserving coupling design and performance as well as protecting the sealing system. Full design via FEA and full scale testing yielded optimized interaction of the seal ring with the annular groove, and the threaded joint of the invention can withstand high axial loads.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects will become more readily apparent by referring to the following detailed description and the appended drawings in which:
FIG. 1 shows a perspective view of a partial section of the joint in accordance with the present invention,
FIG. 2 shows a section view along an axial plane of an embodiment of the joint in accordance with the invention,
FIG. 2 a shows a section view along an axial plane of a detail of the box of the joint in accordance with the invention,
FIG. 3 shows a section view along an axial plane of an embodiment of an element of the joint in accordance with the invention,
FIG. 4 shows a section view along an axial plane of another embodiment of an element of the joint in accordance with the invention,
FIG. 5 shows a section view along an axial plane of another embodiment of an element of the joint in accordance with the invention,
FIG. 6 shows a section view of an enlarged particular of the joint according to the invention in a first working stage,
FIG. 7 shows a section view of an enlarged particular of the joint according to the invention in a second working stage,
FIG. 8 shows a section view along an axial plane of another embodiment of the box of the joint in accordance with the invention.
DETAILED DESCRIPTION
With particular reference to the figures, there is shown a threaded joint indicated overall by reference numeral 1 , connecting two tubes, a male tube 3 , also called a pin, with a nominal external diameter D, and a female pipe 2 , also called a box, of external diameter D 1 .
The pin 3 has a threaded portion 5 , with male threads of appropriate profile, e.g. trapezoidal, and the box 2 has an internal threaded portion 4 with female threads. The common axis of the pipe and the pin and box is indicated by A.
The box 2 ends with a nose 6 . The portion of the box 2 close to the nose 6 comprises a non-threaded surface 7 .
Preferably, but not necessarily, the joint 1 has an internal metal-to-metal seal between the pin nose 6 ′ of the pin 3 and box shoulder 8 .
With particular reference to the embodiment of FIG. 1 , there is provided a housing configured as an annular groove 10 in the box 2 between the end of the thread 4 and the nose 6 . The groove 10 houses a ring 11 forming an external seal when the joint 1 is made up.
In some embodiments, the seal ring 11 performs the function of an external seal placed between the box 2 and the pin 3 or the tube body, such that it prevents leakage of external fluids into the threaded zone of the joint 1 . However, the seal ring 11 could be used in other parts of a threaded joint.
The seal ring 11 is actuated when an external fluid is injected and pressurized through a valve 20 into the housing 10 . This pressure is generated in a chamber 13 and acts onto a surface 25 of the ring, thus deforming and forcing the seal ring 11 both against the sides 14 , 15 , 16 , 17 of the housing 10 and against the pin 3 , to produce a mechanical barrier which seals the joint 1 .
The groove or housing 10 holds, hides and protects the seal ring 11 before injection of the actuation fluid, corresponding to the position as shown in FIG. 6 . Together with the seal ring 11 it constitutes a fluid tight annular pressure chamber when actuation fluid is injected and pressurized through the valve 20 . The valve 20 is a non-return valve and is fixed to the box 2 , the valve tip being advantageously flush with the box surface, to avoid damage to the valve or danger to operators. Injection of the actuation fluid and subsequent energization and activation of the sealing system is performed after the joint 1 is in its final made up position.
The seal ring 11 actuates against a cylindrical surface of the pin member 3 or on the tube body, depending on the position of the housing along the box 2 . This surface where the seal ring 11 contacts the pin 3 is either rolled or machined, and corresponds advantageously, but not exclusively, to the zone comprising the thread run out part. In this manner the pin 3 geometry is not modified, thus the tensional efficiency of the joint remains unaffected.
The actuating fluid may be either a high or low viscosity fluid, such as oil, grease, dope, gel, etc, or a polymer which solidifies after injection, or indeed the fluid present outside the connection, i.e. the same fluid the seal intends to prevent from leaking into the joint.
An advantage of the invention is that the seal ring 11 is protected, since it remains hidden during make up, and is prevented from undergoing any kind of damage, this objective being accomplished without affecting the joint performance.
Another advantage of the invention is the fact that contact pressures deployed by the sealing system are proportional to the pressure of the actuating fluid, these being well known and defined at the moment of injecting and pressurizing the actuating fluid. On the other hand, the magnitude of this actuation pressure is completely independent of the pressure generated by the fluid external to the joint. Furthermore, contact pressures produced by the seal ring 11 are also independent of geometrical parameters of the joint itself, such as ovality, eccentricity, rugosity, and type of connection, and are uniform over the whole circumference of the joint 1 , as geometry, shape, length of both seal and contact areas are variables independent of the joint type.
The internal surface of the seal ring 11 is configured with a plurality of protruding ribs 9 , thus adding sealability, as the adjacent ribs 9 offer multiple subsequent barriers against external fluid when the seal ring 11 is loaded. If one or more barriers leak, subsequent barriers can still withstand the external pressure and ensure sufficient sealing capability.
In a first embodiment of the threaded joint 1 , shown in FIG. 2 , the annular groove geometry has a dovetail or wedge shape in axial section, i.e. its shape is such that the section width increases as the radial distance from the axis A increases, with two lateral surfaces 16 , 17 inclined towards each other.
In this embodiment the groove also has advantageously two annular plane surfaces 14 , 15 opposite and parallel to each other. This particular shape of the groove 10 , when the joint 1 is made up, forces the seal ring 11 to shrink and be energized when pressed by the actuating fluid in the annular chamber 13 .
The section of the seal ring 11 on an axial plane is configured to be housed in the groove 10 and has various alternative shapes, one of which is shown in FIG. 5 complementary to that of the groove 10 . It has a first base 26 with a portion of a frustoconical shape, a second base 27 with a portion of a frustoconical shape axially opposite to the first base, first 26 and second 27 bases being slanted towards the axis A so that its external surface 25 is wider than the internal surface of the seal ring with the ribs 9 .
In an alternative embodiment of the groove 10 , shown in FIG. 2 a , the groove 10 has a simple dovetail section and the associated seal ring 11 has preferably a shape like the ones shown in FIGS. 3 and 4 .
In the embodiments of FIGS. 3 and 5 , the seal ring 11 has also a portion 28 , 29 of each first and second base which has the shape of an annulus.
These shapes of the seal ring 11 yield optimized contact surfaces and optimized seal ring deformation.
The groove 10 radial depth and the seal ring 11 thickness are defined in accordance with the box 2 wall thickness and taking into account the requirement of completely hiding the seal in the groove 10 when the chamber 13 is not pressurized.
The groove 10 has a width of about 15 mm and the seal ring 11 has a similar width, smaller, greater or equal to the groove's width, depending on the geometry of the groove, the shape and material of the seal ring 11 , the type and pressure of the actuating fluid.
The pressure in the chamber 13 can be set to a value between about 100 psi (6.89 bar) and 5000 psi (344.73 bar). This range gives a good seal ring deformation pattern, suitable for the expected range of operation conditions, both in the transient and in the steady state and optimal deformation/stress ratio at concentrating points, necessary to assess seal integrity. Another advantage of a pressure of such magnitude is a good contact pattern between seal and groove, necessary to assess fluid-tight cavity, and a good magnitude and contact pattern between seal and pin, necessary to assess joint sealing capacity.
Actuating fluids for pressurizing seal ring 11 may have either a high or low viscosity fluid, such as oil, grease, dope, gel, etc, or a polymer which solidifies after injection, or indeed the fluid present outside the connection, i.e. the same fluid the seal prevents from leaking into the joint.
An additional advantage of the threaded joint 1 is that its tensional efficiency can be improved by means of this sealing ring 11 . The threaded joint 1 allows, if required for structural reasons, the lengthening of the threaded zone or use of truncated or vanishing threads to be avoided, because the seal ring is mounted and protected in the groove 10 of the box 2 which hides and protects the seal ring 11 within the box 2 . The threaded joint 1 renders superfluous the making of a thread run-out zone (i.e. threads with truncated crests) at the extremities of the thread, when this is made to prevent damage of a seal ring during pre-mounting onto the pin, because the seal ring has to be dragged over the threads. One disadvantage of a thread run-out zone is that the worst stress condition is produced on the seal ring 11 in the last thread of the zone, which has a larger diameter than the nose of the pin 3 and is a reason why threads are truncated. Therefore, in such case valuable thread height is lost for protecting the seal ring 11 .
With particular reference to FIG. 8 , there is shown another embodiment of a joint according to the invention having two seal rings 11 , 11 ′ inserted in two annular grooves 10 , 10 ′ formed in the box 2 . In this embodiment one seal ring 11 is positioned in the portion of the box 2 near its nose 6 which, after make up, faces the portion of the pin 3 after the threaded portion 5 . The second seal ring 11 ′ is positioned in the threadless portion of the box 2 which, after make up, faces the foremost portion of the pin 3 near its nose.
In this embodiment the seal ring 11 ′, like the seal ring 11 , can be formed according to one of the variants as described above. Alternatively, if appropriate for obtaining the best sealing results, the seal ring 11 and 11 ′ can be formed differently from each other: the first seal ring according to one variant among those described above and the second seal ring according to a different variant.
In some specific embodiments of the joint the two rings can be actuated with different pressures of the actuating fluid so that the pressure exerted by one seal ring is either greater or lower than the other.
Alternatively in another embodiment not shown in the figures the joint 1 can be used with the seal ring 11 alone in the position shown in FIG. 8 , but without the seal ring 11 ′. This embodiment can be used for example, but not necessarily, in combination with a metal to metal seal located in the vicinity of the pin 3 nose. The joint of the invention in its various embodiments can almost completely prevent leaking, providing full tightness.
The invention is to be used preferably in the field of OCTG and line pipe connections for the oil & gas industry, especially in offshore applications. | A threaded joint comprises a pin coupled to a box with an annular groove, one or a pair of seal rings, and hydraulic actuating means to pressurize the seal ring or rings against the pin to provide sealability of the joint. The seal ring or rings comprise a frustoconical surface, an external surface, and an internal surface with one or more protruding annular ribs. In the unpressurized state, the seal ring or rings do not protrude from the groove. In the pressurized state, the frustoconical surface of the sealing ring is in sealing contact with an internal surface of the annular groove of the box, and the annular ribs of the sealing ring are in sealing contact with the external surface of the pin. | 4 |
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of the co-pending Italian Application Serial Number TV 2002 A000120, filed Oct. 18, 2002.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to methods and apparatus for sanitizing items. More particularly, the invention relates to improved microwave cooking systems having a plurality of linearly aligned segments for processing food products.
[0003] The invention finds special, but not exclusive application in the sector of collective catering, where sterilization treatment of foods already sealed in containers not to be consumed immediately is required. A second possible application can also concern sterilization or sanitization of other products intended for the food chain, like flour, rice, as well as specific products of various nature, prepared or not, and medicinal products or parts of them. Still a third application of the present invention concerns the sterilization of medical equipment.
[0004] Techniques for conditioning foods for serving of meals to a large number of persons, for example, are certainly known, as occurs in dining halls, in hospitals and other facilities, where large numbers of persons make traditional catering untenable, at least in terms of cost. On the practical side, these techniques can be summarized in three basic steps: a) selection and precooking of foods; b) preservation; and c) serving.
[0005] Conventionally, a cycle of selection and precooking of foods is followed by a preservation cycle, which typically includes the use of refrigerators or freezers and, in more recent techniques, rapid heating vessels.
[0006] In some cases, where preservation on an industrial scale is required, a post-preparation sterilization phase is required between the first and second stages, which, as in the case of use of a container alone, is not limited to attenuation of microbial, pathogenic and enzymatic activity, but has the purpose of destroying all microorganisms present in the product, and also in the actual container/package. This occurs, because the degree of resistance to heat of microorganisms is related to external and environmental factors, like the initial microbial concentration of the medium, the characteristics of the medium itself and the time and temperature parameters, as well as intrinsic factors related to heat sensitivity of germs, development stage of the cells, in which specific variations often occur. For example, under identical environmental conditions, it is observed that fungi and yeast are more resistant than coli bacteria and, within the latter, the rod forms are more resistant that the coccal forms.
[0007] Under practical conditions, to carry out sterilization, it is necessary to heat the product to a temperature between 65° C. and 121° C. for a time of between 5 and 12 minutes. Subsequently, the product must be subjected to the most rapid possible cooling to a temperature equal to or less than 35°.
[0008] The use of high frequency electromagnetic waves, better known as microwaves, is known for performing the sterilization stage. In this sense, GB1103597 (Newton et al.) already suggested a system for controlling microorganisms contains in prepared foods and beverages. It prescribes for exposure of the already prepared foods with the package to electromagnetic waves with a frequency of 20-40 MHz at an intensity of 500-3000 volts for a sufficient period of time to attenuate the microorganisms present in the manufactured product. The use of a magnetron to sterilize materials is known in even greater detail. For example, WO0102023 (Korchagin) proposes a magnetron that has the capacity to implement the intensity of the magnetic field at a level to ensure destruction of microorganisms.
[0009] Complex apparatuses, specifically continuous treatment tunnels for sanitization of packaged products, have been known since 1973. U.S. Pat. No. 3,747,296 (Zausner) proposes an apparatus with linear development, in which filled containers are introduced and subsequently closed. Said containers are passed through the tunnel, which is subdivided into different treatment zones at temperatures between 90° C. and 150° C. Means of irradiation are also provided, which have the purpose of sterilizing the cover only.
[0010] U.S. Pat. Nos. 5,066,503; 5,074,200; 5,919,506 and 6,039,991 issued to Ruozi describe conveyor driven microwave processing plants for pasteurizing, cooking and sterilizing food products. The plants include a plurality of chambers wherein the temperature and pressure are controllable elevated and decreased within as the food products travel from chamber to chamber.
[0011] U.S. Pat. No. 3,889,009 (Lipoma) describes a conditioning tunnel for foods previously prepared in bowls and sealed under pressure. The conditioning tunnel essentially consists of an external covering, along which a conveyor belt moves. At the entry and exit of this tunnel, corresponding to the crossing point of the manufactured vessels, pressure closure doors are provided. Once the sealed vessels have entered the interior of the tunnel, each vessel undergoes a sterilization treatment, passing beneath a source of electromagnetic waves. Each vessel is then transferred downline, always by means of a common belt or chain conveyor, to pass through a cooling unit. A device to generate pressure during the sterilization phase operates within the apparatus to avoid a situation in which the products, because of the process, burst because of the dilation effect, or whose sealing strength is altered. This phenomenon most frequently entails escape of liquid from individual containers, producing not insignificant drawbacks within the apparatus, like accumulation of dirt and the subsequent need to carry out frequent maintenance.
[0012] Other apparatuses based on developments of the system just described are also known. For example, in the catalogs of the Italian companies Modo Group International from Brescia Italy and Micromac from Reggio Emilia, automatic and computerized tunnels are described, which provide for receiving the products, in this case prepared dishes in a heat-sealed vessel, and are designed to carry out the fundamental phases of sterilization treatment. The tunnels include elongate cylindrical constructions have diametrically round cross sections, within which, corresponding to the different stages, the following process phases are conducted: 1) preheating; 2) reaching the sterilization temperature by means of induction devices that generate microwaves; 3) holding or stabilization of the product at the sterilization temperature for a specified time (magnetrons, which are positioned along the lower side of the conditioning tunnel beneath or corresponding to the plane of advance of the prepared foods, are typically provided to execute at least these last two phases); and 4) cooling before unloading. At the end of the process, a finished product emerges, completely sanitized and ready to be packaged and stored in warehouses.
[0013] Unfortunately, the prior art food processing systems suffer from numerous disadvantages. In particular, the previous solutions provide for the necessary magnetrons for gradual reaching and maintenance of the temperature within each product. These devices are situated indifferently along the overlying or underlying side of the line of advance of the heat-sealed bowls/trays/vessels. The cross section of the known conditioning tunnel is round, so that this circumstance actually limits the number of magnetrons that can be located along the axes perpendicular to the direction of advance of the vessels. Consequently, this shortcoming gives rise to two significant defects, in the first place excessive dimensioning (especially in length) of the treatment apparatus, and, when one intends to keep the dimensioning equal to the treated amounts, requiring additional microwave cooling devices, which are particularly expensive, and also difficult to operate and maintain.
[0014] Invariably in the known solutions, owing to the fact that the cross section of the conditioning tunnel is round, the means of longitudinal transport with respect to the tunnel, in the present case a belt or chain, is always contained within the tunnel. This second circumstance actually limits the space available within the tunnel, ultimately reducing the necessary area for treatment of the material. In addition, the presence of a conveyor device almost completely within the tunnel, with all the electromechanical mechanisms necessary for its functioning, offers an infinite number of surfaces and receptacles that are difficult to reach, within which dirt tends to progressively accumulate. The problem is a recurrent one, because the products being treated are, for the most part, food products with frequent presence of liquid, which can also be accidentally dispersed within the tunnel. These events require the use of frequent maintenance, in order to keep the qualitative aspect of treatment high.
[0015] Further problems are associated with the characteristics of the non-return valves that divide each of the stages present along the tunnels of the traditional type. These valves are of the mechanical opening and closing type, whereas the movement that they execute is essentially along a linear axis, using fittings situated peripherally to the closure plate. The negative aspect of these solutions concerns the fact that they are fairly complex and require accurate and constant maintenance to ensure, between the different treatment stages, maintenance of the pressure present in the concerned section.
[0016] Finally, it can happen that during sterilization treatments, in this case, heat-sealed vessels, some of them can burst, dispersing the liquid into the surrounding area. At present, on occurrence of the event, it is necessary to ensure the correct treatment, stop the installation and carry out thorough cleaning with removal of the leaked material.
SUMMARY OF THE INVENTION
[0017] These and other purposes are accomplished with the present innovation by providing a conditioning tunnel for food products, especially for sterilization of food in trays or bowls of the heat-sealed type, including a conditioning unit of the food products, consisting of a tunnel, in which a controlled pressure prevails, subdivided into stages, each stage corresponding to a phase of the treatment cycle that includes at least one heating phase and a cooling phase; a conveyor of the food products from upline to downline through the conditioning unit; openable and closeable doors. arranged along the conditioning unit that separate each stage from the adjacent stage; and means of heating at least one stage of the conditioning unit containing a series of magnetrons. The conditioning unit has an active pressure control system corresponding to at least one heating stage, in which pressure equalization within the heat-sealed trays or bowls is prescribed; a conveyor level, which, through the stages, conveys the heat-sealed trays or bowls along the conditioning unit, which contains mechanisms that can be moved in the plane of the conveyor, positioned outside of the conditioning tunnel; check valves that separate the stages of the conditioning unit; and
[0018] a cross section of the tunnel of the polygonal type; and corresponding to at least one stage of the conditioning unit, a washing liquid input header with corresponding unloading; as well as devices for protection from liquids of each magnetron.
[0019] In this manner, through substantial creative effort, whose effect represents immediate technical progress, some advantages are obtained.
[0020] A first purpose is that of optimizing the conditioning cycle of the food products, which comprises the phases of sterilization. This objective is essentially made possible by the presence of distinct and consecutive phases conducted in the respective stages of a conditioning unit, specifically preheating, heating and stabilization (or holding at a temperature for a certain period of time), each phase prescribing a controlled pressure within the respective stage that balances the pressure relative to the interior of the individual product.
[0021] A second purpose is to make more functional, but also simplify in purely structural terms, the operation of the non-return valves that separate each stage and, at the same time, have them participate actively in controlling the pressure within the different stages of the conditioning unit.
[0022] A third purpose consists, at equal dimensions, of obtaining greater available space within the tunnel by the effect of a quadrilateral cross section. On the practical side, this is conveyed by greater width of the tunnel, so as to increase at least the number of available magnetrons at right angles to the axis of advance of the products being treated. This circumstance therefore permits the treatment of a larger number of products with equal dimensions than with an apparatus of the traditional type.
[0023] A fourth purpose concerns the fact that the absence within the tunnel of movement mechanisms of the advance surface of the food products makes the conditioning unit more reliable in terms of the profile of components, significantly reducing maintenance, which can be conducted outside of the unit, thus reducing the downtimes of the machine, and also in terms of the profile of improved functionality. This circumstance significantly increases the useful treatment capacity of the conditioning tunnel, and also has the purpose of reducing formation of receptacles and spaces, where dirt can accumulate, and the development of bacterial colonies that are difficult to remove because of their location.
[0024] A fifth purposes consists of facilitating maintenance operations within the conditioning tunnel, when dispersion of liquids from the prepared foods occurs. In this case, it is observed that it is not necessary to stop the installation, because the magnetrons are covered by a protective sheath, remaining in a protective and effective condition, even in a case in which the vessels burst. In a subsequent phase at the end of the treatment cycle, more convenient cleaning is permitted, introducing directly into each stage a washing liquid that can then be eliminated through the corresponding discharge.
[0025] These and other advantageous or purposes will be apparent from the subsequent detailed description of some preferred solutions of the implementation by means of the appended schematic drawings, whose details are not intended to limit the invention, but merely exemplify it.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] [0026]FIG. 1 is a side view of the conditioning unit, especially for food products, that provides four distinct stages, connected in succession;
[0027] [0027]FIG. 2 is a side view of the first preheating stage, provided along the conditioning unit according to FIG. 1;
[0028] [0028]FIG. 3 is a cross sectional view of the first stage of the conditioning tunnel according to FIG. 2;
[0029] [0029]FIG. 4 is a side view of the second heating stage of the conditioning unit of FIG. 1;
[0030] [0030]FIG. 5 is a cross sectional view of the second stage of the conditioning tunnel according to FIG. 4;
[0031] [0031]FIG. 6 is a side view of the third stage, corresponding to stabilization or temperature holding in the conditioning tunnel according to FIG. 1;
[0032] [0032]FIG. 7 is a cross section of the fourth stage in the conditioning tunnel according to FIG. 1;
[0033] [0033]FIG. 8 is a side view of the fourth stage, where the cooling phase develops in the conditioning tunnel according to FIG. 1;
[0034] [0034]FIG. 9 is a cross sectional view of the fourth stage of the conditioning tunnel according to FIG. 1;
[0035] [0035]FIG. 10 is a cross-sectional view of the zone affected by the check valve, which connects two adjacent stages in the conditioning tunnel according to FIG. 1;
[0036] [0036]FIG. 11 is a cross-sectional vies of a single check valve door;
[0037] [0037]FIG. 12 is a cross sectional view of the conveyor of the heat-sealed vessels; and
[0038] [0038]FIG. 13 is a graph illustrating the cooking parameters of temperature, pressure and time provided by a preferred food processing system of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0039] With reference to the figures, a conditioning tunnel A is provided for the sterilization and sanitation or various products including medical equipment, food products and other items. Because the conditioning tunnel A is believed to have particular application for the sterilization, sanitization and cooking of foods already packaged in heat-sealed plates, bowls or trays 1 , the conditioning tunnel of the present invention is described with particular application to the processing of food products. However, the conditioning tunnel is not limited thereto, and may be used to process innumerable other items.
[0040] The conditioning tunnel A includes a parallelepipedal unit providing essentially linear development, through which the prepackaged products 1 transit longitudinally. The conditioning tunnel A is constructed by joining the head of one stage to the next one of the other four stages as preassembled modules, respectively, A 1 , A 2 , A 3 and A 4 . Each of the four stages A 1 , A 2 , A 3 and A 4 represents a section of the conditioning tunnel A, within which one phase of the conditioning cycle is reproduced. With reference to FIG. 13, these stages include: A 1 ) preheating; A 2 ) heating and cooking; A 3 ) holding; and A 4 ) cooling. Along stage A 1 , the food, already packaged in plates, bowls or trays and heat-sealed, is subjected to a first preheating phase that brings the dishes from an ambient temperature close to 20° C. to 50° C. Along the second stage A 2 , the packaged dishes coming from the upline phase are then brought from a temperature of about 50° C. to a temperature of about 120° C., to then enter a downline phase A 3 , along which the packaged dishes are held or stabilized for a specified period of time at a temperature no lower than 120° C. At the end of these three phases A 1 , A 2 and A 3 , the packaged dishes are finally transferred downline along stage A 4 , within which a cooling phase is carried out.
[0041] Each stage A 1 , A 2 , A 3 and A 4 of tunnel A is characterized by a typical section that has a rectangular shape on the transverse level with respect to the direction of advance of the packaged dishes 1 and coaxially has an interior chamber 11 , also rectangular in shape, that extends in width between the two inside walls of the main chamber and has a longitudinal development at least equal to that of the corresponding stage A 1 , A 2 , A 3 .
[0042] As shown in FIG. 12, in a preferred embodiment of the invention, the means for conveying the products through the conditioning tunnel is located outside of the tunnel. To this end, along the flanks 2 of the linear structure of each stage A 1 , A 2 , A 3 and A 4 , apertures 20 are provided. The apertures 20 are longitudinally aligned and equidistantly positioned through the sidewalls of the chamber 11 . A support shafts 3 projects through the apertures from the outside of the conditioning tunnel, entering the inside 31 of the chambers 11 of stages A 1 , A 2 , A 3 and A 4 . At the corresponding end 31 inside the chamber 11 of stage A 1 , A 2 , A 3 and A 4 , a wheel 4 is mounted, which has the purpose of keeping the packaged dishes 1 in movement. As shown in FIG. 12, the wheels support and propel the food products 1 , a shown bowls, which have, at least on the side, a protruding lip 10 that is supported on the wheel 4 . Rotation of one or more of the wheels 4 along the left and right sides of stage A 1 , A 2 , A 3 and A 4 is caused one or more motors and chains drives. These means of transmission and rotary motion are positioned on the outside along each flank of the stages A 1 , A 2 , A 3 and A 4 , engaging the end of shaft 3 , which has on the opposite end a corresponding toothed wheel 32 . In this manner, by interaction of wheels 4 , an idler is obtained that moves longitudinally, from upline to downline, the packaged dishes 1 through each stage A 1 , A 2 , A 3 and A 4 , in a logical sequence controlled by a logic control unit. Preferably, the conveyor can move the food products forward or rearward through the conditioning tunnel. Moreover, preferably the conveyor provides an oscillating movement of the food products forwardly, or forwardly and rearwardly, to alter the magnetic field seen by the packages to provide more uniform heating. For example, the conveyor may move food products forwardly, followed by periodic pauses, to provide uniform heating. Alternatively, the conveyor may move the products forwardly and rearwardly in an oscillating manner to provide uniform heating.
[0043] Advantageously, by providing the motors and chain, or other drive mechanism, exterior to the chamber, the conveyor provides a minimum of surfaces within the chambers which are capable of collecting dirt or accidentally spilled food products. Moreover, though the drive mechanism of the present invention may include a shaft which projects across the interior of the chambers 11 , preferably, and as shown in FIG. 12, the drive mechanism includes wheels which project only a few inches into each side of the chamber for supporting and propelling the food products 1 . A traditional conveyor belt assembly with its corresponding rollers and belts are excluded, there eliminating additional surfaces which a capable of collecting dirt and accidentally spilled food products.
[0044] As reflected in FIG. 13, each stage A 1 , A 2 , A 3 and A 4 is also provided with a control system for controlling the internal pressure in the chamber for balancing the corresponding pressure present within the individual packaged dishes 1 . It is known that during temperature treatments, the containers have a tendency to dilate to formation of steam. The presence of a controlled pressure within each of the stages A 1 , A 2 , A 3 and A 4 has the purpose of avoiding bursting of the containers and dispersal of the liquids inside of the conditioning tunnel.
[0045] Each stage A 1 , A 2 , A 3 and A 4 is separated from the adjacent one by means of a check valve 5 . The check valve 5 essentially comprises an almost flat gate 50 with dimensions slightly greater than opening 12 , made in the corresponding dividing wall that separates heating stage A 1 , A 2 , A 3 and A 4 from the adjacent one. On the perimeter from the occluded side, the gate 50 is provided with a fitting 1 that is mounted around opening 12 , so as to guarantee effective sealing. On the other side, the gate 50 has a support bracket 52 that is linked on the top to a gear 53 engaged by a rack 54 that is moved along the vertical axis by a cylinder 55 . In this case, the movement of the rack 54 is functional only to permit raising of the oscillating gate 50 , whereas to carryout closure, the difference in pressure existing between the two connected stages A 1 and A 2 , A 2 and A 3 , A 3 and A 4 will cause the gate to be released and fall freely to block opening 12 . In this case, it is therefore comprehensible how the pressure generated downline along conditioning tunnel A, affected by stages A 1 , A 2 , A 3 , will always be greater than that generated in the upline stage. With addition of the cooling stage A 4 of the packaged dishes 1 , where a pressure essentially less than that present in the stage immediately upline A 3 , the provision of a stabilization stage A 3 with two valves 5 is required (see FIG. 1), which open and close in opposite directions to each other. In different fashion, the valves 5 present in stages A 1 and A 2 have a single direction of opening, which is essentially facing downline.
[0046] Preferably, the conditioning tunnel of the present invention includes one or more temperature sensors for sensing the temperature of the products transported through stages A 1 - 4 . The temperature sensors may be any type as can be determined by those skilled in the art. For example, traditional temperature sensors positioned adjacent to the path of the food products may be employed. However, infrared thermal cameras or sensors which measure, or pictorially display, the temperature of all containers within a stage are believed preferable. Also, preferably the infrared thermometers operate at a wavelength of approximately 1.8 μm and communicate sensor data using fiber optics to reduce the disruption generated by the substantial electromagnetic field within the chambers 11 . Typically, the measured temperature is the surface temperature of the container storing the food product. However, the exterior temperature of the container provides an accurate estimate for the temperature of the product within the container.
[0047] Preferably, during the transportation of the containers 1 through the tunnel, the temperature sensors continuously read the temperature of the containers, carrying out ten measurements on each container. The tunnel of the present invention produces a profile of each container and compares the profile parameters to reference values to ensure that each product is properly conditioned. As explained in greater detail below, if a product is determined to have been heated insufficiently, or too greatly, the system alters the heating parameters to properly condition the food products.
[0048] To permit heating of the packaged dishes 1 , at least in stage A 1 , A 2 , and corresponding to the lower side 13 or the upper side 14 , openings 130 , 140 are provided, within which microwave generators are housed, like magnetrons. Each magnetron, in the present case, is covered with a non-stick protective sheath, constructed of Teflon or similar material. Owing to the particular conformation of the cross section of each stage A 1 , A 2 , A 3 , it is possible to provide many magnetrons, distributed in aligned rows within each stage. In a preferred embodiment, the first two stages A 1 and A 2 include three rows of eight magnetrons for a total of 24 magnetrons in each chamber. Preferably, stages A 3 and A 4 do not include magnetrons.
[0049] In a preferred embodiment of the invention, the magnetrons are cooled by water and generate 2000 W at a frequency of about 2,450 Mhz. Preferably the magnetrons produce magnetic field impulsively, in a non-constant manner, to avoid burning of products on the edges. A protective shield covers the magnetrons to protect against liquids and other bits of product. The shield, made of Teflon or similar substance, may create small reduction of the microwave field. However, such reductions are considered insubstantial. In a preferred embodiment of the invention, the magnetrons are controllable to produce electromagnetic fields that can controlled in both intensity and movement. If a product is determined to have been heated insufficiently, or too greatly, the magnetrons may be adjusted to alter the heating parameters to properly condition the food products. For example, where food products within the electromagnetic field of the magnetrons are found to have been heated less than expected, power to the magnetrons is increased to provide additional heating. Conversely, where the food products are determined to have been heated greater than expected, the power to the magnetrons is decreased to reduce heating to the food products.
[0050] Alternatively, the conditioning tunnel of the present invention may include magnetrons that produce an electromagnetic field which can be moved longitudinally or laterally with respect to the axis of the tunnel. To this end, the magnetrons may be connected to gimbals, tracks or other mechanical apparatus for physically moving the magnetrons relative to the tunnel to produce electromagnetic fields that can be controllably moved or rotated to alter the electromagnetic fields encountered by individual food products. Different mechanical apparatus for moving or rotating the magnetrons can be determined by those skilled in the art. Alternatively, the magnetrons may be constructed to passively move the electromagnetic field within conditioning tunnel, without physically moving the magnetrons. Constructions for passively moving the magnetic field can also be determined by those skilled in the art without undue experimentation.
[0051] Preferably, A 2 and A 3 also include inlets permitting entry of supply of hot air and aspiration 17 . Air supplied at approximately 130° Celsius is believed acceptable for processing and cooking most foods. Finally, preferably stage A 4 includes a cooling system including inlets, or nozzles, projecting through the stage A 4 sidewalls for presentation of a cold water spray for cooling the food products. The water preferably includes an anti-freeze additive, as can be selected by those skilled in the art, for ensuring that the cooling spray is supplied at about 1° Celsius and does not freeze and clog the water inlets.
[0052] Any, or all, of the stages A 1 - 4 may include additional cleaning fluid inlets for washing the interior of the conditioning tunnel. To this end, the stages may include nozzles projecting through the stages' sidewall which are connected to a supply of cleaning fluid to permit washing of the interior of the stages. To this end, water inlets 15 and corresponding discharges 16 are provided, positioned along each stage.
[0053] Preferably, the conditioning tunnel is fully automated, including one or more control processors for controlling the chambers' pressure, conveyor, check valve doors, magnetrons and cooling system. The control processor is also preferably connected to the temperature sensors so that temperature measurements can be used by the control processor for determining operation of the magnetrons and conveyor. For example, preferably the conveyor is adjustable to move products forward and rearward within the conditioning tunnel. Based upon temperature measurements, the control processor causes the conveyor to move products forward or rearward into, or out from, respective magnetic fields generated by the magnetrons to provide even and thorough heating of the products. Similarly, the control processor may cause the magnetrons to increase, decrease, or move the magnetic field depending on temperature measurements of the food products. For example, temperature measurments indicating that particular food products have reached desired temperatures may cause the controller to decrease the magnetic field encountered by the food product: 1) by decreasing the power to the associated magnetron; 2) by moving the food product away from the relevant magnetic field by causing the conveyor to move the food product forwardly or rearwardly, or 3) by causing the magnetic field to move relative to the food product by physically moving the relevant magnetron or causing the relevant magnetron to passively move magnetic field relative to the food product. Conversely, temperature measurements indicating that a food product has not achieved a desired temperature may cause the control processor to: 1) increase the power to the associated magnetron; 2) move the food product into the relevant magnetic field by causing the conveyor to move the food product forwardly or rearwardly, or 3) cause the relevant magnetic field to move relative to the food product by physically moving the relevant magnetron or causing the relevant magnetron to passively move magnetic field relative to the food product.
[0054] Although particular preferred embodiments of the present invention have been described herein, it is to be understood that variations may be made in the construction, materials, shape and use of the conditioning tunnel system without departing from the spirit and scope of the invention. Having identified the presently preferred best modes of practicing the invention, we claim: | Tunnel is provided for conditioning of food products, especially for sterilization of food in containers or vessels of the heat-sealed type, in which the conditioning unit has: 1) an active pressure control system corresponding to at least one heating stage, which provides for balancing of the pressure within the heat-sealed vessels or containers; and 2) a conveyor which conveys the heat-sealed vessels or containers through the stages along the conditioning unit which contains mechanisms that move the conveyor outside of the conditioning tunnel, and 3) doors operating like check valves that separate the stages of the conditioning unit; and 4) a cross section of the tunnel of the polygonal type; and 5) the conditioning unit including inlets for introduction of washing liquids with a corresponding discharge outlet. Preferably, the magnetrons are covered to protect each magnetron from liquids. In preferred embodiments, the conditioning tunnel includes temperature sensors for measuring the temperature of products within the tunnel. Moreover, preferably the conveyor is adjustable to move forward and rearward, and the magnetrons are adjustable to provide a controllably moveable magnetic field. A controller is connected to the temperature sensors, conveyor and magnetrons to cause the conveyor to move products forward or rearward, or cause the magnetrons to move the magnetic field relative to the food products to more thoroughly and evenly cook the food products. | 7 |
This application is a division, of application Ser. No. 6/544,364, filed Oct. 21, 1983, now U.S. Pat. No. 4,491,610, patented Jan. 1, 1985.
BACKGROUND OF THE INVENTION
The present invention relates to vapor permeation curable coating compositions and more particularly to a curing chamber with constant gas flow environment which is designed especially to cure said coating compositions.
Vapor permeation curable coatings are a class of coatings formulated from aromatic-hydroxyl functional polymers and multi-isocyanate cross-linking agents wherein an applied film thereof is cured by exposure to a vaporous tertiary amine catalyst. In order to contain and handle the vaporous tertiary amine catalyst economically and safely, curing chambers have been developed. Generally, such curing chambers are substantially empty, rectangular boxes through which a conveyor bearing the coated substrate passes. Provision is made for entrance and exit of vaporous tertiary amine, normally borne by an inert gas carrier such as nitrogen or carbon dioxide, for example, and means are provided at the inlet and outlet of the chamber to enhance containment of the vaporous tertiary amine catalyst within the chamber. The inlet and outlet containment means further restrict the entrance of oxygen into the chamber because oxygen can create an explosive condition with the vaporous tertiary amine catalyst. Cure of such coatings is so rapid that no external source of heat is required.
Representative examples of past curing chambers are set forth in U.S. Pat. Nos. 3,851,402, 3,931,684, and 4,294,021. Of particular note in the patented curing chambers is the provision made at the inlet and outlet for containment of the vaporous tertiary amine curing gas within the chamber. For example, U.S. Pat. Nos. 3,851,402 and 3,931,684 provide moist air curtains at the inlet and outlet which moist air curtains along with a source of suction are designed to minimize escape of tertiary amine gas from within the chamber. Somewhat different is the design in U.S. Pat. No. 4,294,021 which calls for the exhaust fan to create a slight negative pressure to induce gas flow within the chamber in the direction of the exhaust duct which is located near the exit of the chamber. It is noted by the patentees that air is dragged by the conveyor from the inlet and such flow of air along with the vaporous amine circulates from the entrance of the chamber to the exhaust duct where the gas is withdrawn for recirculation. The patentees further note that the negative pressure created at the exhaust duct near the outlet also creates a flow of air from the exhaust end of the chamber into the chamber itself. No provision in this patent is seen for minimizing air flow into the chamber and, to the contrary, the design appears to encourage the flow of air into the chamber.
While prior curing chambers certainly have performed adequately in the marketplace, many problems exist with prior designs. One problem with prior designs is the loss of amine vapor. Another problem is the inability to prevent air from entering into the curing portion of the chamber. A further disadvantage is the inability to operate at rapid conveyor belt speeds. The present invention addresses these and other deficiencies in the prior art and provides a unique chamber as will be more fully appreciated by the description contained below.
BROAD STATEMENT OF THE INVENTION
The present invention is directed to a curing chamber which defines a constant gas flow environment for passing objects therethrough carried by transporting or conveyor means, such as a conveyor. The chamber is ideally suited for vapor permeation curing of flat substrates carried by the conveyor. The chamber comprises an elongate housing having an inlet opening and an outlet opening in the longitudinal direction and a moving conveyor, which preferably is an endless conveyor, which runs the length of the housing for transporting objects from the inlet opening through said housing and out of said chamber through said outlet opening. The space below the conveyor is enclosed and is connected to a source of exhaust for exhausting gaseous substances therein. The space above the conveyor comprises an inlet zone, a central gas flow zone, and an outlet zone. The inlet zone comprises an outer inlet adjustable gate for determining the inlet opening, a middle inlet adjustable baffle gate, and an inner inlet deflector wall. The space between the outer gate and the inlet baffle gate is connected to exhaust means. The space between the inlet baffle gate and the inner inlet deflector wall is a modulating gas cell which contains a gas knife connected to a source of inert gas. The gas knife is capable of injecting the inert gas at an adjustable angle onto the conveyor substantially the entire width of the conveyor. The outlet zone comprises an adjustable outer gate which determines the outlet opening, a middle outlet adjustable baffle gate, and an inner outlet deflector wall. The space between the outer outlet gate and the middle outlet baffle gate also is connected to exhaust means. Preferably, the enclosed space between each outer gate and each baffle gate is maintained at substantially the same pressure within the inlet zone and the outlet zone which pressure typically is slightly less than atmospheric pressure. The space between the inner outlet baffle gate and the inner outlet deflector wall in the outlet zone also is a modulating gas cell which contains a gas knife. The outlet gas knife also is connected to a source of inert gas which is capable of injecting the inert gas at an adjustable angle onto the conveyor substantially the entire width of the conveyor.
The central gas zone has withdrawal means located in proximity to the inlet deflector wall which withdrawal means are connected to recirculating means for passing gaseous flow back into said central gas zone. The recirculating flow is passed back into the central flow zone at a location in proximity to the inner outlet deflector wall. Both the inlet and outlet deflector walls are sloped downwardly and inwardly. Preferably, such sloped surfaces are smooth and curvilinear.
Advantages of the present invention include the ability to maintain a gas composition substantially constant even at relatively high conveyor belt speeds. Another advantage is the ability to effectively exclude oxygen, i.e. air, from the interior of the curing chamber. A further advantage is the minimization of losses of gas, e.g. a tertiary amine or the like in vapor permeation curing adaptations of the invention, which contributes to the efficiency and economy of the design of the curing chamber. A further advantage is the conservation of inert diluent gas advantageously used in connection with vapor permeation cure adaptations of the present invention. These and objects will be readily apparent to those skilled in the art based upon the disclosure contained herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation view of a prototype curing chamber of the present invention fitted with an endless conveyor;
FIG. 2 is a side elevation view of the chamber of FIG. 1 sectioned through the center of the chamber in the longitudinal direction;
FIG. 3 is a cutaway view of the gas knife assembly located both at the inlet and at the outlet ends of the chamber;
FIG. 4 is an enlarged side elevation view showing the details of the gas knife assembly;
FIG. 5 graphically plots nitrogen gas consumption of the prototype curing chamber as a function of conveyor belt speed for various constant TEA chamber concentrations;
FIG. 6 graphically plots TEA consumption of the prototype curing chamber as a function of conveyor belt speed for various constant TEA chamber concentrations; and
FIG. 7 graphically plots TEA consumption for the prototype curing chamber at constant TEA chamber concentrations for various constant conveyor belt speeds.
These drawings will be described in detail in connection with the description of the invention which follows.
DETAILED DESCRIPTION OF THE INVENTION
The curing chamber of the present invention comprises several unique aspects which operate conjunctively to the overall efficiency and economy of the curing chamber for containment of a constant gas flow environment to the exclusion of the ambient atmosphere. These conditions are maintained while a conveyor is passed through the curing chamber at a relatively high speed. Unique design concepts implemented in the novel curing chamber of the present invention include the bicameral containment sections at the inlet and outlet, the use of fully adjustable gas knives, and the countercurrent flow circuit within the central gas zone. Such design concepts, while dominant in the process, are not limitative of the unique, and often subtle, features embodied within the curing chamber.
Referring to FIG. 1, curing chamber 10 is seen fitted with conveyor 12 driven by motor 16 at the outlet of chamber 10 with follower 14 at the inlet of chamber 10. Follower 14 rests upon frame 18 while motor 16 rests upon frame 20. Chamber 10 is designed for having flat substrates passed therethrough on conveyor 12 which rests upon slide plate 44. The curing chamber, as depicted in the drawings as noted above, is a prototype having endless conveyor belt 12 being 30.48 cm (1 foot) in width and an overall inside width of about 40.64 cm (16 inches). For present purposes, conveyor is used in a generic sense to mean any suitable means for conveying or transporting a coated substrate through the chamber for its curing. The entire length of chamber 10 is about 7.32 meters (24 feet) and its height is about 50.8 cm (20 inches). Chamber 10 is supported by a series of struts 22 which place the bottom of housing 8 of chamber 10 about 0.92 meter (3 feet) above the level of floor 24. One of the safety features fitted onto chamber 10 is emergency vent 26 which is fitted with an internal blow out diaphragm in conventional fashion. Should undesirable pressures build up within chamber 10 or an explosive condition be created therein, the safety diaphragm would rupture and the contents of chamber 10 would be immediately vented through line 26. Many other safety features are incorporated into the design of the prototype chamber depicted in the drawings and these features will be noted as the description of the drawings unfolds. The remaining piping depicted in FIG. 1 will be described in detail in connection with the description of the remaining drawings.
Referring now to the unique bi-cameral containment arrangement of the curing chamber, it must be recognized that the essence of the bicameral containment arrangement is effectively identical for the inlet section as for the outlet section. While both bi-cameral inlet zone 30 and bi-cameral outlet zone 32 operate to exclude oxygen and retain a desired internal atmosphere, it should be recognized that conveyor 12, especially at higher belt speeds, will drag atmosphere from the outside to within chamber 10. Thus, the primary focus of inlet bi-cameral zone 30 is to prevent such entering atmosphere from passing into central gas zone 34 and the primary function of bi-cameral outlet zone 32 is to prevent the escape of the atmosphere within central gas zone 34 from being dragged by conveyor 12 to the outside. With respect to containment of the atmosphere within central gas zone 34, it should be noted that, depending upon the material of construction of endless conveyor 12, such conveyor may have a tendency to absorb or adsorb the particular gaseous environment maintained within central flow zone 34. Chamber 10 is fitted with extended, elongate hood 36 which houses the return loop of endless conveyor 12. Hood 36 is formed by the lower half of housing 8 and conveyor slide plate 44. Hood 36 is connected to a source of exhaust which removes components contained within hood 36 through outlet pipes 38, 40, and 42. Should any leakage between central flow zone 34 and hood 36 develop, the withdrawal suction placed thereon would prevent such leakage from finding its way to the atmosphere. It is to be noted that when using a tertiary amine for vapor permeation curing purposes of chamber 10, often the exhaust lines such as lines 38, 40, and 42, for example, would be passed through an appropriate scrubber, e.g. an acid, for scrubbing the amine from such flow. Other gaseous components desirably utilized in chamber 10 similarly may require scrubbing so that the withdrawal lines can be piped directly to scrubbers, vented to the atmosphere, or utilized in a by-product process as is necessary, desirable, or convenient in conventional fashion.
Returning to FIG. 2, inlet bi-cameral zone 30 is divided into outer cell 50 and inner cell 52. Outer cell 50 is defined by adjustable outer footed gate 54 and centrally located bi-footed, stationary gate 56. Outer footed gate 54 is adjustable vertically to define the opening of the chamber so that substrates of varying heights can be accommodated. Outer cell 50 is connected to a source of suction through line 58 which is shown in FIG. 1 to be connected to exhaust header 134 along with exhaust lines 38, 40, and 42. Exhaust line 58 maintains cell 50 at a total pressure of slightly less than the prevailing environmental atmospheric pressure. Oxygen or air which enters into chamber 10 desirably will be withdrawn from cell 50 via line 58 in order to prevent its entrance into central gas zone 34. The footed arrangement on gates 54 and 56 again tend to suppress gaseous flow as part of the integrated containment design of the curing chamber of the present invention. Inner cell 52 is defined by central stationary bi-footed gate 56 and adjustable inner footed gate 60 which bears deflector wall 64. Gate 60 is adjustable vertically for accommodation of substrates of varying thicknesses as is outer gate 54. Central fixed bi-footed baffle gate 56, which also may be adjustable, and inner adjustable gate 60 define modulating gas cell 52. Cell 52 desirably functions as a modulating or compression zone to provide a desirable transition between outer exhaust cell 50 and interior central gas zone 34.
Referring to FIG. 4, gas knife 70 is adjustable by handle 72 (see FIG. 3). From FIG. 3, it can be seen that gas knife 70 runs substantially the entire width of belt 12 and is connected to a source of inert gas from both sides through lines 74 and 76. Plates 78 and 80 have holes extending therethrough for permitting pipes 74 and 76, respectively, to pass therethrough to gas knife 70. Sealing of inert gas pipes 74 and 76 is accomplished via gaskets 82 and 84, respectively, Also, plate 78 bears a protractor for determining the angle at which gas knife 70 incidences upon conveyor belt 12. From FIG. 3 it can be seen that adjustable gate 60 is retained within guides 86 and 88 which are on both sides of gate 60 for providing a recessed track for gate 60 to follow. A flow of inert gas, e.g. nitrogen, carbon dioxide, or the like (supplied from line 150), flows through gas knife 70 through the lower slit which measures about 0.0635 mm (0.0025 inch) or less and faces belt 12 at an angle as depicted by its position 90 in FIG. 4. The angle at which knife 70 contacts belt 12, while being adjustable between 0° and 50°, has been found to advantageously range from about 10° to about 20° based upon several factors which will be elucidated in more detail below. Knife 70 is retained within gas knife housing 94 as shown in FIG. 4. Inner cell 52 desirably predominates in an inert gas composition provided by gas knife 70 and is the transition from oxygen-rich outer cell 50 and oxygen-starved central gas zone 34. The momentum of the inert gas flow through gas knife 70 is adjusted (flow rate and angle) to balance the momentum of the air layer on belt 12 and, thus, control the oxygen level in central zone 34.
Outlet bi-cameral zone 32 similarly is divided into outer cell 102 and inner cell 104. Outer cell 102 is connected to a source of suction via line 106 as is outer cell 50. Cell 102 is defined by outlet adjustable footed gate 108 and central stationary bi-footed baffle gate 110. The pressures within cells 50 and 102 desirably are maintained to be the same. Inner compression cell 104 is defined by baffle gate 110 and inner adjustable gate 112. The arrangement of inner adjustable gate 112 is identical to inner gate 60 as previously described for inlet bi-cameral zone 30, i.e. as described in FIGS. 3 and 4. In this instance, however, the gas knife (supplied via line 152) for bi-cameral outlet zone 32 is adjustable by handle 103 and faces conveyor 12 at an angle contra the direction of the conveyor (i.e. as position 92 in FIG. 4 assuming FIG. 4 was a view of gate assembly 112 from the opposite side of chamber 10 as shown in FIG. 2). The angle of the outlet knife generally ranges from about 20° to 45° based upon several factors which will be set forth below. The construction of assembly 112 also is identical to the construction as described in FIG. 3 for gate assembly 60. Operation of bi-cameral outlet zone 32 again is identical to that as described in detail for inlet bi-cameral zone 30 and will not be dwelled upon further. It should be noted at this juncture of the discussion that the pressure and/or gas composition within any zone or cell of chamber 10 is determined by use of sampling ports 114a-114j.
Central gas flow zone 34 has a gas flow contained therein which is in countercurrent relationship to the direction of movement of endless conveyor belt 12. Such gas flow movement is provided by gas flow withdrawal line 120 which is located in proximity to bi-cameral inlet zone 30 and return line 122 which is located in proximity to bi-cameral outlet zone 32. The direction of movement of the gas through zone 34 is assisted by deflector walls 64 and 124 which are borne by inner gate assemblies 60 and 112, respectively. The gas flow movement, velocity, and direction is determined by in-line fan or blower 126 (see FIG. 1). Additional make-up gas, e.g. tertiary amine catalyst, is provided through line 128 which enters withdrawal line 120 as shown in FIG. 1. This arrangement permits intimate mixing of the flows through lines 120 and 128 by blower 126. Line 122 immediately following blower 126 is heated by line 130 which desirably can be a steam line, heated tape, or any similar desirable conventional heating system. For use of a vaporous tertiary amine catalyst, for example, it is desirable to provide such heating in order to ensure the vaporous phase of the tertiary amine catalyst and to prevent condensation of such catalyst. For use of different gases in chamber 10, it may be desirable to provide a source of cooling rather than heating through line 130. Similarly, line 128 may be heated for a vaporous tertiary amine catalyst or cooled for other gases in conventional fashion. Another feature of the chamber is that inert gas is provided through line 137 to the chamber to maintain a slightly higher pressure in central zone 34 than in inlet zone 30 and outlet zone 32 in order to minimize the infiltration of air (oxygen) into central zone 34. The oxygen conentration in zone 34 also can be maintained at a desired level by supplying nitrogen through lines 137 and 122 to zone 34. As noted above, additional safety features included into the prototype curing chamber in the drawings include line 132 (FIG. 1) extending from line 120. Line 132 is connected to the source of suction provided through exhaust header 134. Line 132 can be automatically activated for evacuation of the contents of central zone 34. Another safety feature is inert gas line 136 (FIG. 1) which flows into line 122. Line 136 can have a flow of inert gas immediately passed into line 122 and thence into central gas zone 34 should the level of oxygen, for example, become too high and a potentially explosive condition be imminent.
Operationally, extensive testing and observation of the prototype curing chamber of the drawings has permitted qualitative analysis of variables determinative of efficient operation of the chamber and quantification of such variables. Optimization of such variables even has been determined to a large extent based upon the data accumulated. The prototype curing chamber was operated under vapor permeation cure conditions utilizing triethylamine (TEA) vapor catalyst borne by nitrogen as the carrier gas. Nitrogen flow also was utilized for the gas knives. The data generated is accurate for the chamber design substantially independent of the particular gas components evaluated. Data collected included the belt velocity, the recycle volume, the composition of TEA and oxygen in chamber 34, the flow of inert gas through and incident angle of both the inlet and outlet gas knives, and the total consumption of TEA and nitrogen in the system. In addition to the data collected and tabulated, many of the variables were varied while others remained constant in order to assess their impact on the operation of the chamber. These variations will appear as observations following the tables below. All gas flows rates are standardized for a temperature of 15.6° C. and 1 atmosphere.
TABLE 1__________________________________________________________________________ TEA Chamber Inlet Knife Outlet Knife Consump-Run Belt Vel. Recycle (vol %) Flow Angle Flow Angle tionNo. (m/min) (L/min) TEA O.sub.2 (L/min) (deg) (L/min) (deg) (Kg/hr)__________________________________________________________________________1 24.4 1500 1.60 4.0 31.1 10 42.5 25 0.342 82.4 1415 2.20 5.7 31.1 10 53.8 45 0.693 91.5 1500 2.86 5.0 31.1 20 53.2 45 0.744 91.5 1500 4.05 5.6 31.1 20 53.2 45 1.34__________________________________________________________________________
Observations
As a general trend, as the desired TEA concentration in the chamber is increased, so is the TEA consumption (loss) increased. On runs 3 and 4, an increase of the inlet knife (70) angle to 30° or a decrease of the inlet knife (70) angle to 10° resulted in an increase of oxygen concentration within zone 34. Also, with a lower volume of nitrogen flowing through the outlet knife, the oxygen concentration in its chamber increased.
TABLE 2__________________________________________________________________________ TEA Chamber Inlet Knife Outlet Knife Consump-Run Belt Vel. Recycle (vol %) Flow Angle Flow Angle tionNo. (m/min) (L/min) TEA O.sub.2 (L/min) (deg) (L/min) (deg) (Kg/hr)__________________________________________________________________________1 91.5 1500 4.60 5.6 31.1 20 53.8 45 1.502 91.5 1500 5.00 5.6 31.1 20 53.8 45 1.683 122.0 1500 2.10 6.1 31.1 20 58.0 45 0.724 122.0 1500 4.90 6.2 31.1 20 58.0 45 1.67__________________________________________________________________________
Observations
Runs 1 and 2 show that even at a constant belt speed, increasing TEA chamber concentrations resulted in increased TEA consumption. On run No. 3, when the knife angle for the inlet knife was increased to 25°, the oxygen concentration in the chamber increased. At an inlet knife angle of 15°, the oxygen concentration in the chamber decreased only slightly. On run No. 4, when the exit knife was varied to an angle of 50° with an increased flow of 62.3 liters per minute, the oxygen concentration in the chamber did not vary. At the increased angle of 50° for the exit knife, at the same 53.8 liter per minute gas flow, the oxygen in the chamber increased. At the increased angle of the exit knife of 50°, an increase of the gas flow to 65.1 liters per minute resulted in no significant improvement of the oxygen concentration in the chamber.
TABLE 3__________________________________________________________________________ TEA Chamber Inlet Knife Outlet Knife Consump-Run Belt Vel. Recycle (vol %) Flow Angle Flow Angle tionNo. (m/min) (L/min) TEA O.sub.2 (L/min) (deg) (L/min) (deg) (Kg/hr)__________________________________________________________________________1 30.5 1557 1.90 3.9 31.1 10 42.5 28 0.442 30.5 1557 2.25 3.5 31.1 10 42.5 27 0.623 30.5 1557 3.90 3.8 31.1 10 42.5 27 1.044 61.0 1557 1.90 4.0 31.1 10 42.5 45 0.545 91.5 1557 1.58 5.6 31.1 20 53.8 45 0.546 91.5 1557 2.30 5.0 31.1 20 53.8 45 0.827 91.5 1557 3.05 5.7 31.1 10 53.8 45 1.078 91.5 1557 3.37 5.7 31.1 20 53.8 45 1.14__________________________________________________________________________
Observations
The results of runs 1 and 4 show that with a doubling of the belt velocity, the TEA and oxygen concentration in the chamber can be maintained substantially the same by merely increasing the angle of the outlet gas knife.
TABLE 4__________________________________________________________________________ TEA Chamber Inlet Knife Outlet Knife Consump-Run Belt Vel. Recycle (vol %) Flow Angle Flow Angle tionNo. (m/min) (L/min) TEA O.sub.2 (L/min) (deg) (L/min) (deg) (Kg/hr)__________________________________________________________________________1 24.4 1500 3.03 4.3 31.1 10 42.5 25 0.622 30.5 1557 3.30 3.8 31.1 10 42.5 25 0.833 61.0 1557 3.35 4.8 31.1 10 42.5 25 0.934 122.0 1557 1.80 6.0 31.1 20 59.5 45 0.625 122.0 1557 2.72 5.6 31.1 20 58.0 45 0.926 122.0 1840 2.76 5.5 31.1 20 58.0 45 0.927 122.0 1982 2.76 5.5 31.1 20 58.0 45 0.928 122.0 2265 2.73 6.0 31.1 20 58.0 45 0.929 122.0 1840 3.99 5.8 31.1 20 59.5 45 1.36__________________________________________________________________________
Observations
Runs 5, 6, 7, and 8 maintained all variables constant but the recycle. These results demonstrate that the recycle can be increased to a level whereby the oxygen concentration in the chamber increases. Apparently, there is an optimum recycle for the chamber which results in a minimization of oxygen concentration therein, provided that all other variables remain essentially unchanged.
Based upon the data tabulated above and the experience garnered by operation of the prototype chamber, optimization of the inlet and outlet knife angles and flow rates have been determined based upon the conveyor speed. These optimized design variables assume the exhaust rate from cells 50 and 102 each will be about 425 L/min (15 SCFM) and the recycle flow rate through lines 120 and 122 will be less than 2265 L/min. With these conditions, and based upon the conveyor speed, the angle and flow rate through the knives will permit the oxygen concentration in the chamber to be maintained at less than 6%, generally 3-6%, and a constant TEA concentration maintained ranging up to about 5%.
TABLE 5______________________________________OPTIMUM SETTINGS AT VARIOUS BELT SPEEDS Inlet Knife Outlet KnifeConveyor Speed Flow Flow(m/min) Angle (°) (L/min) Angle (°) (L/min)______________________________________15.25 10 31.1 20 36.824.40 10 31.1 25 42.530.50 10 31.1 25 42.561.00 10 31.1 40 42.591.50 20 31.1 45 53.8122.00 20 31.1 45 58.8______________________________________
As will be noted, the N 2 flow rate and knife angle of the outlet knife appears to be more important in maintaining the TEA and oxygen balance within the system.
While the data tabulated in Tables 1-4 above provide an accurate operating history of the prototype chamber, such data can be assembled and correlated to provide interesting and valuable information concerning the total TEA consumption and total nitrogen consumption for the chamber. This information is presented as a function of the belt speed and as a function of chamber concentration of TEA.
TABLE 6______________________________________Total N.sub.2 Consumption (L/min)Belt Speed TEA Chamber Concentration (vol %)(m/min) 1 2 3 4 5 Avg.______________________________________24.4 112.13 112.41 111.28 110.43 110.15 111.2730.5 117.51 117.23 116.66 115.81 115.25 116.4961.0 131.39 130.82 130.25 128.84 128.27 129.9191.5 150.92 150.07 149.51 148.09 147.53 149.23122.0 159.42 158.57 158.00 156.59 155.74 157.66______________________________________
TABLE 7______________________________________TEA Consumption (Kg/hr)TEAChamber Conc. Belt Speed (m/min)(vol %) 24.4 30.5 61.0 91.5 122.0______________________________________1.0 0.21 0.25 0.29 0.33 0.341.6 0.34 -- -- 0.54 --1.8 -- -- -- -- 0.621.9 -- 0.44 0.54 -- --2.0 0.41 0.51 0.57 0.67 0.682.1 -- -- -- -- 0.722.3 -- 0.62 -- 0.79 --2.7 -- -- -- -- 0.922.9 -- -- -- 0.98 --3.0 0.62 0.77 0.85 1.01 1.123.3 -- 0.83 -.93 -- --3.4 -- -- -- 1.1 --3.9 -- 1.04 -- -- 1.364.0 0.83 1.03 1.13 1.34 --4.6 -- -- -- 1.50 --5.0 1.04 1.28 1.42 1.68 1.70______________________________________
The above-tabulated data also is depicted graphically in FIGS. 5-7. FIG. 5 graphically depicts the nitrogen consumption as a function of belt speed at various constant TEA chamber concentrations. As can be seen from the data in Table 5, the nitrogen consumption primarily is a function of the belt speed and appears to be substantially independent of the TEA concentration in the chamber. It should be noted that the amount of nitrogen required to maintain central zone 34 at a desired oxygen concentration can be supplied manually through lines 137 and 122 into zone 34. The overall consumption of nitrogen, though, remains substantially constant at the varying concentrations of TEA within the chamber. FIG. 6 graphically depicts the consumption of TEA as a function of the belt speed at various constant TEA chamber concentrations. Quite clearly the increased TEA consumption at increased TEA chamber concentrations is seen. Also, the TEA consumption is increased at increased belt speeds and such TEA consumption increases at a greater rate at higher TEA chamber concentrations for increasing belt speeds.
FIG. 8 graphically depicts the TEA consumption as a function of TEA chamber concentration at various constant line speeds. The TEA consumption is shown to be essentially linearly related to the chamber concentration and appears to asymptotically approach a maximum consumption based upon line speed.
The foregoing data demonstrates the remarkable efficiency and economy of the design of the chamber of the present invention. Also, the apparent important variables in chamber design have been identified qualitatively and quantitatively. It will be appreciated that various modifications of the chamber can be implemented without departing from the philosophy and scope of the present invention.
It will be appreciated that the nature of the gas environment through the central flow zone merely can be heated air or can be simply a carrier gas (e.g. nitrogen, carbon dioxide, or the like). Appropriate insulation or lagging of the chamber may be required under such circumstances if heat transfer is of prime concern. Materials of construction are conventional for the type of operation contemplated. Thus, stainless steel, galvanized steel, glass-lined steel or the like is used as is necessary, desirable, or convenient in conventional fashion. Where erosion or corrosion is inconsequential, mild steel, aluminum or the like may be used. Alternatively, the carrier gas can bear a catalyst such as a vaporous tertiary amine catalyst. For practice of vapor permeation cure with the chamber of the present invention, a good discussion on various types of vapor permeation curable coating compositions can be found in commonly assigned U.S. Pat. application Ser. No. 474,156, filed Mar. 10, 1983, the disclosure of which is expressly incorporated herein by reference. Such copending application describes and references a variety of polyols, multi-isocyanates, and optional solvents for formulating vapor permeation curable coatings. In this application, all percentages of gaseous components are volume percentage and all units are in the metric system, unless otherwise expressly indicated. | Disclosed is a chamber which defines a constant gas flow environment for passing objects therethrough carried by a conveyor. The chamber comprises an elongate housing having an inlet opening and an outlet opening in the longitudinal direction and a moving conveyor which runs the length of said housing for transporting object from said inlet opening through said housing and thereout through said outlet opening, the space below said conveyor being enclosed and connected to a source of exhaust for exhausting gaseous substances therein. The space above the conveyor comprises an inlet zone, a central gas zone, and an outlet zone. The inlet zone and the outlet zone both are of a bi-cameral containment arrangement comprising an outer adjustable gate for determining the inlet opening, a central adjustable baffle gate, and an inner deflector wall. The space between the outer gate and the baffle gate is connected to a source of exhaust. The space between the baffle gate and the deflector wall is a modulating gas cell which contains a gas knife connected to a source of inert gas and capable of injecting said inert gas at an adjustable angle onto the conveyor substantially its entire width. The central gas flow zone operates under external recycle of its atmosphere in a direction countercurrent to the direction of the conveyor belt which passes therethrough. The chamber is ideally suited for vapor permeation curing of flat substrates coated with a vapor permeation curable coating. | 5 |
FIELD OF THE INVENTION
This invention relates to optical signal mode converters with very high efficiency tuning capability.
BACKGROUND OF THE INVENTION
Tunable broadband mode-converters play an important role in WDM optical communication systems. They may be used to dynamically convert a lightwave signal propagating in one mode of a few-mode fiber, into another spatial mode. Such coupling is attractive to alter the path the lightwave signal takes, because the alternate path (defined by another spatial mode in the fiber) may have preferred dispersion, nonlinearity, or amplification properties. An example of this is a higher-order-mode dispersion compensator, where light in an entire communications band is switched from an incoming LP 01 mode to a higher-order-mode (HOM) such as the LP 11 or LP 02 mode. See for example: C. D. Poole et al., J. Lightwave Tech ., vol 12, pp.1746-1758 (1994); S. Ramachandran, et al., IEEE Photon. Tech. Lett ., vol 13, pp. 632-634 (2001); A. H. Gnauck et al., Proc. Opt. Fiber Comm ., PD-8 (2000); U.S. Pat. Nos. 5,185,827, 5,802,234.
In a general sense, long-period gratings are mode-conversion devices that provide phase-matched coupling to transfer power from one mode of an optical fiber to another. (See, e.g., J. N. Blake, B. Y. Kim and H. Shaw, “Fiber-Optic Modal Coupler Using Periodic Gratings,” Opt. Lett. 11,177(1986); J. N. Blake, B. Y. Kim, H. E. Egan, and H. J. Shaw, “All-Fiber Acusto-Optic Frequency Shifter,” Opt. Lett. 11, 389(1986); and J. N. Blak, B. Y. Kim, H. E. Egan, and H. J. Shaw, “Analysis of Intermodal Coupling in a Two-Mode Fiber with Periodic Microbends,” Opt. Lett. 12, 281(1987)). This has proven to be especially useful for coupling between a guided mode and a cladding mode of ordinary transmission fibers, to create wavelength selective loss (See, e.g., M. Tachibana, R. I. Laming, P. R. Morkel and D. N. Payne, “Erbium-Doped Fiber Amplifier with Flattened Gain Spectrum,” IEEE Phot. Tech. Lett. 3, 118(1991)). In optical communications systems, LPGs have been used extensively for realizing devices that offer wavelength-selective attenuation of a WDM communications signal.
Most of the applications for LPGs have concentrated on static wavelength attenuation. Dynamic tuning of the spectral characteristics of LPGs has been proposed, and a variety of dynamic tuning techniques have been demonstrated. LPGs that couple the core mode to a cladding mode can be tuned dynamically by modulating the refractive index of an outer or inner cladding material that is interrogated by a cladding mode of the fiber. The refractive index of such cladding materials can be varied by temperature, the electro-optic effect or some nonlinear optical effect, depending on the nature of the cladding material used. Alternately, the LPGs may be strained by piezoelectric packages, simple motion control housings or magnetically latchable materials, to tune the core-to-cladding resonance. All these tuning techniques have been applied to LPGs coupling core modes to cladding modes, and offer tunable attenuation over a limited, narrow spectral range. The tuning mechanisms described above serve to shift the spectral response of LPGs from one wavelength to another. While these techniques are useful for tuning the wavelength selective attenuation in a fiber-optic system, they cannot be used for broadband mode-conversion schemes. This is because the devices transform light into a cladding mode, and cladding mode transmission is known to be inefficient. Thus these devices are not useful in systems that propagate signals over long lengths, as are required for devices such as the HOM dispersion compensators. In addition, the spectral width of mode coupling with current tunable LPGs is undesirably narrow. Typical bandwidths are ˜1 nm for 99% mode-conversion, while a practical device would need more than a 40 nm bandwidth. While chirped LPGs have been proposed to enhance the bandwidth, the approach introduces an inherent trade-off between bandwidth and strength of mode-conversion. Most importantly, the tuning that is most desirable for dynamic filters is in the strength of the coupling, and not the resonant wavelength. The devices described above provide only the latter form of tunability.
Broadening the bandwidth of LPGs by coupling to a higher-order cladding mode has been described by V. Grubsky et al., “Long period fiber gratings with variable coupling for real-time sensing applications, Optics Lett ., Vol. 25, p. 203 (2000). In this device, greater than 50-nm coupling has been achieved, albeit with weak coupling strengths. The coupling strength was tuned by temperature or strain, but the device suffered from the drawback that it coupled to a cladding mode, which is lossy in nature. The spectral characteristics of this device were controlled by the silica cladding of a fiber. This structure is not amenable to arbitrary control, and thus the spectral shape or characteristics could not be altered, as would be required of a practical mode-converter.
Thus, there exists the need for a fiber-grating device that can offer strong broadband coupling, preferably over bandwidths exceeding 30 nm, whose coupling strength is tuned by temperature, strain, the electro-optic effect, the nonlinear optic effect, or any other means that modifies the refractive index of a material. A practical device would offer mode-conversion such that the converted mode can be propagated for long distances without significant attenuation.
STATEMENT OF THE INVENTION
According to the invention, a few mode fiber is used for the mode converter, and coupling is made between a fundamental, or near fundamental, propagation mode and the next, or closely adjacent, higher order mode (HOM). Both modes propagate in the core of the optical fiber, thus maintaining efficient transmission. Mode coupling is effected using a long period grating (LPG) and the strength of the mode coupling is dynamically varied by changing the period of the grating or by varying the propagation constants of the two modes being coupled. The period of the grating is varied by physically changing the spacing between grating elements, for example by changing the strain on the grating to physically stretch the LPG. The propagation constants of the modes can be varied using any method that changes the refractive index of the fiber containing the LPG, for example, by changing the temperature, electrically changing the index using the electro-optic effect, or optically changing the index using the non-linear optic effect. In every case the two modes being coupled are core modes with high propagation efficiency.
In the following description an LPG formed in a few mode fiber is referred to as an HOM-LPG.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic representation of a HOM-LPG mode converter according to the invention;
FIG. 2 is a plot of wavelength vs. LPG period showing the spectral properties of an HOM-LPG;
FIG. 3 is a plot of intensity vs. wavelength showing the coupling efficiency of an HOM-LPG, with curves comparing the HOM-LPG with a conventional LPG;
FIG. 4 is a plot of intensity vs. wavelength showing the coupling efficiency of HOM-LPGs with different grating spacing;
FIG. 5 is a plot of wavelength vs. LPG period illustrating a graphical relationship for the strength of mode coupling;
FIG. 6 is a plot of wavelength vs. LPG period showing the effect on the phase matching curve of varying the temperature of the grating;
FIG. 7 is a plot of wavelength vs. mode intensity showing the effect on coupling strength of varying the temperature of the grating;
FIG. 8 is a plot of wavelength vs. LPG period to compare the case of a grating spacing at the minima in the phase matching curve (FIG. 1) with a grating spacing the intersects the phase matching curve;
FIGS. 9 and 10 are plots of wavelength vs. transmitted (mode) intensity for the two cases shown in FIG. 8 .
DETAILED DESCRIPTION
The basic structure of the HOM-LPG mode converter is illustrated in FIG. 1 . The optical fiber is shown with core 11 and cladding 12 . The LPG is shown at 13 . A temperature control element for tuning the HOM-LPG is shown at 14 . The temperature control means is typically a thermoelectric device for either heating or cooling the core of the optical fiber.
FIG. 2 shows the phase-matching curve, 21 , that determines the spectral properties of LPGs induced in HOM fibers. An important feature in the phase matching curve for these specially designed HOM fibers is the existence of a turn-around-point (TAP), shown on the curve. These fibers support more than one spatial mode in the core region. When the LPG grating period is chosen to couple at the TAP, shown by the line 22 in FIG. 2, large bandwidth mode-coupling is achieved.
A TAP in an optical fiber exists when two modes (or more) have group indices that are essentially the same. The group index of a propagating mode is a well-known and well-defined optical parameter. It may be represented by:
n
g
=n−λdn/dλ
where n g is the group index, n is the refractive index and λ is the wavelength. For the purpose of defining the conditions useful for practicing the invention, one of these is the existence of a TAP in the fiber containing the LPG. Another is the ability of the fiber to support at least two core-guided modes. Core-guided modes are those in which the predominant energy envelope of the propagating mode resides in the core region of the optical fiber. In a typical fiber, greater than 60% of the light energy in a core-guided mode propagates in the center 60 microns of the glass fiber. In contrast cladding modes have more than 40% of the energy outside this region.
FIG. 3, shows the typical spectrum, 31 , of light remaining in the LP 01 mode of the HOM fiber after the coupled LP 02 mode is stripped out, and also shows the corresponding spectrum of conventional LPGs, 32 . It is apparent that bandwidth improvements by a factor of 60 or more are achieved with HOM fibers.
FIG. 2 also shows additional curves representing grating periods at slight deviations from the TAP grating period, i.e. curves 23 , 24 , and 25 . FIG. 4 shows the LPG spectra for gratings with these grating periods, i.e. curves 41 , 42 , and 43 , respectively. As is evident, slight deviations from the TAP grating period leads to changes in the coupling strength of the grating. Note that while the strength of coupling changes, the spectral shape remains nominally the same. This is in contrast to conventionally tuned LPGs, where tuning shifts the resonant wavelength of the spectrum.
The origin of this effect can be understood by realizing that the coupling efficiency, η, of a uniform LPG (that determines the amount of light coupled by the LPG) is given by: η = ( κ L ) 2 · sin 2 ( ( κ L ) 2 + ( δ L ) 2 ) ( κ L ) 2 + ( δ L ) 2 ( 1 )
where κ is the coupling coefficient, which is proportional to the amount of index change induced in the fiber, L is the length of the grating, and δ is a detuning parameter, given by: δ = 1 2 ( 2 π λ Δ n - 2 π Λ ) ( 2 )
where λ is the wavelength, Λ is the grating period, and Δn is the difference in the effective refractive indices between the LP 01 and LP 02 modes, respectively. A resonance occurs, and strong coupling is achieved when the condition δ=0 is satisfied. Eq. 1 indicates that the coupling strength decreases with a Sinc functional dependence, as δ deviates from zero. Equation 2 represents the resonance condition for a LPG, and the phase matching curve shown in FIG. 2 is a trace of the wavelength, λ versus the grating period Λ when the detuning, δ=0. The line 21 in FIG. 2 represents the grating period when the grating couples at the TAP—that is, when the δ=0 condition is satisfied at the TAP. The lines 23 , 24 , and 25 in FIG. 2, represent different grating periods, none of which intersects the phase matching curve, 21 . From Eq. 1 and 2, we can deduce that for grating periods represented by the lines 23 , 24 , and 25 , δ is larger than zero at all wavelengths. This implies that the coupling strength is less than optimal at all wavelengths. In addition, it is apparent from FIG. 2 that δ becomes progressively larger, for the curves 23 , 24 , and 25 , respectively. Likewise, the corresponding spectrum in FIG. 4 shows that curves 41 , 42 , and 43 show progressively weaker coupling. Further, for all grating periods (represented by lines 22 , 23 , 24 , and 25 ), FIG. 2 shows that δ is minimum at the TAP wavelength. Since Eq. 2 indicates that maximum coupling is obtained for minimum δ, FIG. 2 indicates that all gratings would yield maximum coupling at the TAP wavelength. This is indeed the case, as is evident upon inspection of FIGS. 3 and 4.
Thus, as general rule, and with reference to FIG. 5, we infer that the coupling strength of a grating can be deduced by inspecting the phase matching curve 51 for the particular fiber (e.g. FIG. 2 ), and drawing a horizontal line 52 on it that represents the grating period. The relative strength of coupling at any wavelength is then proportional to the length of a line 53 connecting the phase matching curve 51 and the grating line 52 . This rule is strictly true for Gaussian apodised gratings, and is approximately true for uniform gratings. Thus, the coupling strength of this new class of gratings may be changed without perturbing their spectral shapes. Strength tuning can be achieved by strain, which serves to change the grating period, as is illustrated in FIG. 2 (spectra in FIG. 4 ). Alternately, the grating period can be held constant, and the phase matching curve can be moved. The phase matching curve is determined by the waveguide properties (such as the difference in effective indices of the two modes, Δn, as shown in Eq. 2). This may be changed by any means that changes the refractive index profile of the fiber. FIG. 6 shows the shift in the phase matching curve as result of changing the ambient temperature from T 1 to T 2 to T 3 . Curve 61 is for T 1 , curve 62 is for T 2 , and curve 63 is for T 3 . The grating period, represented by curve 64 , is held constant. Since only the relative distance between the phase matching curves 61 , 62 and 63 and the grating period line, 64 , is required to determine the level of coupling, the changes represented here should produce similar effects to straining (FIGS. 2, 3 and 4 ). FIG. 7 shows the grating spectra at temperatures T 1 , T 2 , and T 3 . In FIG. 7, curve 71 is for T 1 , curve 72 is for T 2 , and curve 73 is for T 3 . The expected decrease in coupling strength is evident, as the grating period and the TAP of the phase matching curve become more removed.
FIG. 5 shows, for example, a grating period departure from the TAP point that is approximately 0.5% ((112.8−112.2)/112.8). FIG. 2 indicates that the grating period (or the TAP point) may be set as desired at any of several relative positions. However, in the practice of the invention reasonably efficient coupling will be desired. To this end, the TAP and the grating period Λ, for the lower order mode in the mode converter, should be within 5%, and preferably within 2%. It should be understood that these ranges apply to both the case of FIG. 2 (Λ at or below the TAP minima) and FIG. 8 (Λ at or above TAP minima).
While temperature was used in FIGS. 6 and 7 as the control parameter to shift the phase matching curve, the effect is also realized by any physical mechanism that dynamically alters the refractive index profile of the fiber containing the HOM-LPG. These mechanisms include, but are not limited to, stress-optic, thermo-optic, nonlinear-optic, acousto-optic or electro-optic effects that alter the refractive indices of one or more layers of material used in defining the core or cladding environment of an optical fiber.
The previous examples and illustrations show how a fiber with a TAP in its phase matching curve can be used to realize a mode-coupler with variable strength by shifting the grating period away from the phase matching curve. The same concept holds when the grating period is shifted to intersect the phase matching curve at two discrete points, as shown in FIG. 8 . This figure shows a phase matching curve, 81 , with a TAP at 1540 nm, and two lines, 82 and 83 , representing two distinct grating periods, 96.885 μm, line 82 , and 97.215 μm, line 83 . FIGS. 9 and 10 show the spectral response for the two modes that are coupled by the LPG, the LP 01 and the LP 02 modes. The spectral response in FIG. 9 corresponds to the case (FIG. 8) where the grating period is at line 82 , i.e. well removed from the TAP. FIG. 10 gives corresponding spectral response for the case with the grating spacing at line 83 of FIG. 8, i.e. where the grating spacing is set at the TAP in the phase matching curve. Note that in FIG. 8, the grating period represented by line 82 , intersects the phase matching curve at two wavelengths. In addition, following the insight gained from FIG. 5 and Eqs. 1 and 2, we infer that a grating at this period offers very little coupling at the TAP wavelength region, since δ≠0 (see Eq. 6 and discussion in relation to FIG. 5 ), at the TAP. Thus, very little coupling is expected. This is observed in the spectra of FIG. 9 . The curve 91 represents the light in the LP 01 mode at the output of the LPG. The spectrum shows resonances at two wavelengths, approximately 1490 nm, and approximately 1600 nm. The resonances correspond to the wavelengths where the phase matching curve 81 of FIG. 8 intersects the grating period curve 82 . On the other hand, in the wavelength region close to the TAP, between approximately 1530 nm and 1565 nm, the transmitted intensity in the LP 01 mode is almost 0 dB, corresponding to full transmission. Since a substantial portion of the light remains in the LP 01 mode for this case, no significant power is expected to reside in the LP 02 mode at the output of this LPG. This is illustrated by curve 92 of FIG. 9, which shows that the transmitted power in LP 02 mode is less than −20 dB in the wavelength range of 1530 nm to 1656 nm. FIG. 10 shows the spectral response obtained with an LPG whose grating period is represented by line 83 in FIG. 8, i.e. where the grating period is set at the TAP in the phase matching curve. FIG. 10 shows that a strong broadband resonance is obtained, such that the power in the LP 01 mode, represented by curve 101 , is reduced to levels below −20 dB in the wavelength region close to the TAP (1530 nm to 1565 nm). At the same time the power in the LP 02 mode, represented by curve 102 , is close to 0 dB (unity transmission) in the same wavelength range. This example illustrates that the relative position of the grating period with respect to the phase matching curve is not limited by the relationship shown in FIGS. 2, 5 , and 6 , i.e. where the grating period is separated from the phase matching curve, but that broadband variable coupling can be achieved by shifting the relative positions of the phase matching curve and the grating period in either direction. The example illustrated in FIGS. 8-10 also indicates that this concept may be used to build “ON/OFF” switches to shuffle light between various modes of a fiber.
While the foregoing illustrations pertain to mode coupling between the LP 01 and the LP 02 mode, the same concept can be generalized to LPGs that offer coupling to other core-guided modes. Both modes of interest may be “higher order” modes, for example the LP 11 mode and the LP 02 mode. Alternatively, coupling may be produced between more than one mode simultaneously. For example, intended coupling may occur between mode LP 01 , and both LP 02 and LP 11 . In this context, the choice of the kind of LPG used to fabricate these devices would depend on the preferred modes of choice. It may be preferable to use symmetric gratings (such as UV-induced LPGs) for coupling between the fundamental (LP 01 mode) and a symmetric mode (such as the LP 02 mode). On the other hand, it may be preferable to use asymmetric gratings, such as microbend LPGs induced by pressing corrugated surfaces on the HOM fiber, or by acousto-optic excitation, for coupling the fundamental mode with an anti-symmetric mode (such as the LP 11 mode) of the HOM fiber.
As noted earlier, several applications may be envisaged for a mode-converter with variable coupling. Of particular interest are adjustable dispersion compensators. These are described in detail in my co-pending application filed of even date herewith entitled: “ADJUSTABLE DISPERSION COMPENSATOR WITH FEW MODE FIBERS AND SWITCHABLE MODE CONVERTERS” which is incorporated herein by reference. In these devices one or more switchable HOM-LPGs may be combined with specified lengths of HOM fiber. The lengths of HOM fibers possess different amounts of dispersion in different spatial modes The switchable mode converter may then be used as a means of adjusting the amount of dispersion accumulated by the lightwave signal by preferentially directing the signal into a spatial mode with desired dispersion properties. This yields a tunable dispersion device.
Conventional LPGs are used as variable optical attenuators. These find applications in, for example, WDM systems for channel equalizers. They may also be used as modulators. In either case the HOM-LPG devices described above may offer equivalent functions but with higher efficiency and versatility. The LPG device may be constructed such that the higher order mode is always attenuated at the output of the LPG. This can be achieved by bending the fiber, or by adding mode-stripping tapers in the HOM fiber, after the LPG. Varying the strength of the coupling leads to varying loss values, since only the LP 01 mode is transmitted through the device.
The devices described above may also be used as simple 2×2 routers and/or switches. The switchable LPG of the invention can be combined with a mode-selective fused fiber coupler to extract the HOM out of the fiber, at the output of the LPG. Thus, the converted light can be directed into another fiber, thus achieving the functionality of 2×2 routing and switching.
The LPGs described here may be formed by various techniques. A common approach is to write the gratings into a Ge doped fiber using UV light. See, e.g., A. M. Vengsarkar, P. J. Lemaire, J. B. Judkins, T. Erdogan, and J. E. Sipe, “Long-Period Fiber Gratings as Band-Rejection Filters,” J. Lightwave Tech., 14, 58(1996); A. M. Vengsarkar, J. R. Pedrazzani, J. B. Judkins, P. J. Lemaire, N. S. Bergano, and C. R. Davidson, “Long-Period Fiber-Grating-Based Gain Equalizers,” Opt. Lett., 21, 336(1996); and J. A. Rodgers, R. J. Jackman, G. M. Whitesides, J. L. Wagener, and A. M. Vengsarkar, “Using Microcontact Printing to Generate Amplitude Photomasks on the Surfaces of Optical Fibers: A Method for Producing In-Fiber Gratings,” Appl. Phys. Lett. 70,7(1997)). These references are incorporated herein by reference for details of LPG construction. However, other methods may also be used. For example, microbend induced LPGs are suitable. These can be realized with acousto-optic gratings, arc-splicer induced periodic microbends, or by pressing the fiber between corrugated blocks that have the required grating periodicity.
The physical constitution of LPGs is well known. Basically an LPG is similar to the familiar Bragg grating and comprises a length of optical waveguide wherein a plurality of refractive index perturbations are spaced along the waveguide, but the spacing is characterized by a relatively long periodic distance Λ. Typically Λ is at least 10 times larger than the transmitted wavelength, λ. In the usual case, Λ will be in the range 15-1500 micrometers, and the width of a perturbation in the range ⅕ Λ to ⅘ Λ. In some applications, such as chirped gratings, the spacing Λ will vary along the length of the grating.
In the discussion above reference is made several times to a minima in the phase matching curve, and the figures show a minima in the usual sense. However, it will occur to those skilled in the art that the TAP could as well be a maxima point, or it could be an inflection point, where the slope as well as the second derivative of the curve are both essentially zero. For the purpose of definition herein, the use of the term minima is intended to include the case where the TAP occurs at a maxima or an inflection point. In the former case, a maxima may be shown as a minima by simply inverting the scale.
Various additional modifications of this invention will occur to those skilled in the art. All deviations from the specific teachings of this specification that basically rely on the principles and their equivalents through which the art has been advanced are properly considered within the scope of the invention as described and claimed. | The specification describes optical mode converters wherein coupling is made between a fundamental, or near fundamental, propagation mode and the next, or closely adjacent, higher order mode (HOM). Both modes propagate in the core of the optical fiber, thus maintaining efficient transmission through the mode converter. Mode coupling is effected using a long period grating (LPG) and the strength of the mode coupling is dynamically varied by changing the period of the grating or by varying the propagation constants of the two modes being coupled. The period of the grating is varied by physically changing the spacing between grating elements, for example by changing the strain on the grating to physically stretch the LPG. The propagation constants of the modes can be varied using any method that changes the refractive index of the fiber containing the LPG, for example, by changing the temperature, or electrically changing the index using the electro-optic effect. In every case the two modes being coupled are core modes with high propagation efficiency. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a bougie device and method of use thereof, and more particularly relates to a device for gripping and directing a bougie device which is suitable for guiding insertion of an endotracheal tube into an airway of a person.
[0002] A bougie may have numerous uses in medicine, but are commonly used to widen a passageway or guide another instrument into a passageway. An intubation aide commonly known as the “gum elastic bougie” is a thin, solid or hollow, cylinder of rubber, plastic or another material that a physician inserts into a body passageway. Within the art of tracheal intubation, bougies are frequently used as a guide for the correct placement of an endotracheal tube. Bougies are also used to provide suction or oxygen delivery within a body passageway.
[0003] Bougies generally require a necessary level of flexibility so that they can navigate a body passageway, with the required flexibility resulting in bougies that are hard to grip. Devices have been designed to assist in intubation of the bougie, i.e. guiding the bougie, but such devices still have limitations in allowing for adequate gripping of the bougie so that it can he properly navigated during a procedure.
[0004] In many medical situations endotracheal intubation is a critical procedure performed to secure a patient's airway. To facilitate insertion of an endotracheal tube, a physician, paramedic or other medical personnel will use a laryngoscope blade which is inserted down a patient's throat. The laryngoscope blade is primarily used to move the tongue and the epiglottis from the providers view in order to provide a clear passage to the vocal cords. Placement of the endotracheal tube correctly in the patient's trachea must be done quickly to avoid hypoxic brain injury to the patient. The task of endotracheal intubation becomes more challenging in emergent situations, patients with difficult airways and those that are at high risk for aspiration.
[0005] Commonly in the operating room prior to induction of general anesthesia patients are given 100% oxygen to breath in effort to replace nitrogen in the lungs with oxygen. This process is known as preoxygenation and serves to fill the lungs with oxygen like a reservoir. When patients undergo general anesthesia they become apneic and must rely on the oxygen reservoir within the lungs to provide oxygen for the bodies basic metabolic needs. Sufficient preoxygenation adequately fills the lungs with oxygen to provide more time for the medical personnel to instrument the airway and attempt endotracheal intubation.
[0006] Evaluation of a patient's airway allows physicians to gauge the difficulty that may be encountered when attempting endotracheal intubation. Certain clinical features of patient such a large neck circumference, obesity, history of sleep apnea, small mouth opening, and overbite among, others are predictors of a difficult endotracheal intubation. Once a patient has been deemed to have a difficult airway, the physician may obtain equipment such as a video laryngoscope or intubation aide like the bougie. A physician may have a poor view of a patient with a difficult airway of the vocal cords under direct laryngoscopy, which would make endotracheal intubation difficult. The bougie is vital tool in the difficult airway as it has a bended tip that facilitates its passage into the patient's trachea.
[0007] Commonly found within hospitals is suction tubing with a handle attached, also known as a yankauer, which are used to aspirate fluid within the patient's airway. Under direct laryngoscopy, the yankauer provides direct vision of the patient's vocal cords. In an effort to overcome these problems, medical personnel often insert the yankauer to remove blood, oral secretions, or gastric content prior to proper placement of the endotracheal tube. After aspiration of fluid within the pharynx the suction device must be removed and an endotracheal tube must be inserted within the trachea. This two step procedure of clearing secretions, gastric contents, or blood with the suction tube removing it and then grabbing an endotracheal tube results in lost time. However, these prior art processes use valuable time, along with the patient's oxygen reservoir, switching between devices. Moreover, even when suction tube is inserted into the mouth it is possible fluids to reaccumulate in between the time suction tube is removed and endotracheal tube insertion.
[0008] If an intubation attempt fails, then the patient must be ventilated with bag and mask device which can force air down the trachea as well as down the esophagus. When the stomach is extended with air, patient becomes more likely to vomit and aspirate. A distended abdomen also decreases a patient's lung compliance and makes it more difficult to ventilate. Moreover, repeated intubation involves instrumenting the airway with laryngoscope blade which causes trauma to the patient which can result in bleeding and edema. It is vital that endotracheal intubation be accomplished quickly, accurately, atraumatically and on consistently on the first attempt. Repeated attempts with intubation often make endotracheal intubation even more challenging. A distended abdomen from bag-mask ventilation, bleeding, or edema can obstruct the physician's view of the vocal cords and places the patient at risk for aspiration. This is a common problem with the current intubation procedure with a difficult airway has been taking time to exchange between using the bougie, yankauer, and the endotracheal tube. This lost time puts the patient at risk for aspiration pneumonia, aspiration pneumonitis, or hypoxic brain injury.
[0009] U.S. Pat. No. 5,257,620 describes an airway device that has a suction stylet that telescopically disposed therein and attached to the endotracheal tube. The suction stylet is connected to a suction source which allows suction forces to withdraw fluids continuously. During the intubation process, if continuous suction forces at the distal suction stylet are present it can cause trauma to the vocal cords. Furthermore, a suction device that lacks complete control by the provider may be problematic as continuous suction in the oropharynx will also remove oxygen from the patient. Continuous suction of oxygen from the patient oropharynx will hasten the development of hypoxia. This takes away valuable time the provider has when attempting to intubate the patient and must revert to bag-mask ventilation. As hypoxia develops patients are at risk for developing anoxic brain injury and even cardiac arrest.
[0010] U.S. Pat. No. 5,595,172 describes a device that includes a suction stylet that is inserted into an endotracheal tube and allows the provider to control suction. The stylet has a main body with a central passageway along the main body and a vent arm that extends off the main body. The vent arm has a vent port that allows the provider to utilize suction with occlusion of the vent port. This device may offer a suction stylet that can be only be used to clear secretions but does not function as an intubation aide.
SUMMARY OF THE INVENTION
[0011] The present invention provides a gripping device for a solid or hollow bougie or bougies during an intubation procedure. The hollowed bougie can be connected to external tubing, e.g. suction tubing or oxygen tubing.
[0012] The present invention may further comprise a suction bougie that can be used to aspirate fluids as well as an intubation guide for insertion of an endotracheal tube into the airway of a patient. Commonly, when a medical personnel performs a direct laryngoscopy of a patient's airway to assess for adequate visualization of the vocal cords, the presence of oral sections, blood, masses, or gastric contents. The airway device mentioned above is primarily used for patients with a difficult airway, or who are at risk for aspiration of gastric contents. Management of these patients often necessitates that an intubation guide commonly known in the field as gum elastic “bougie” and an oral suction device. The bougie may be used if there is poor visualization of the vocal cords and a suction apparatus is needed to clear oral secretions or gastric contents to provide an unobstructed view of the vocal cords. The use of either the bougie or suction requires the medical personnel to switch between handling either device. The proposed invention allows the medical personnel to use the bougie and suction simultaneously without having to spend time to exchange devices. This ultimately removes inherent delays in securing the airway.
[0013] The invention as mentioned functions as an apparatus that attaches to a bougie to facilitate endotracheal intubation. The apparatus may be attached to a pre-existing bougie intubation aid as well a suction bougie. The suction bougie is designed as a hollow tube to be used as a suction bougie. The suction bougie may comprise of an elongated body that is hollow at both the proximal and distal ends. The distal of the tube would have several open ports to allow for passage of oral secretions, blood, or gastric contents. The proximal end would be connected to a curved bougie holder. The body of the bougie device may be formed from Teflon, polytetrafluoroethylene, or plastic polymer which would result in a self lubricated device. This would reduce the need for the bougie device to be lubricated for insertion into the airway of a patient.
[0014] The present invention is designed with a curved handle that has a curved side opening, e.g. a channel, to receive either a solid or hollow bougie. The curved handle preferably will generally be rigid and preferably manufactured from a hard plastic material.
[0015] The proximal end of the handle will encompass a hollow tube with one end to be attached to the proximal end of the suction bougie or an oxygen delivery bougie. The handle is designed with a curved and enclave where the bougie is meant to reside within with an outside force, i.e. the gripping force of the user's fingers, which allows the bougie to be moved to a curved patter, and also stabilizes the bougies by increasing the gripping area during intubation. After the bougie is attached to the proximal end of the handle, the bougie will then be bent around itself with its distal portion nestled within the curved handle. The other end of the hollow tube of proximal handle will be connected to suction tubing or oxygen tubing commonly found within the hospital. The hollow tube will have a vent port that when occluded by the medical personnel's finger will allow suction force from the distal tip of the suction bougie. When the vent port is not occluded there will be no suction force at the tip of the suction bougie. The importance of having a vent port allows the medical personnel to have complete control over when to utilize the suction function. Moreover, a suction device that lacks complete control by the provider because continuous suction of oxygen from the patient oropharynx may cause hypoxia. The invention can be used as an oxygen delivery device, as well.
[0016] The present invention also allows for telescopically advancement of an endotracheal tube over a bougie prior to advancement of a bougie into a patient's trachea. The endotracheal tube can be immediately advances over the bougie into the trachea.
[0017] The apparatus may be used with the pre-existing bougie to provide a more ergonomic way to use the bougie. The bougie is commonly must be manipulated by the medical personnel to incorporate a curve for endotracheal insertion. The curve of the bougie is meant to follow the natural curvature of the patient's oropharynx. However a common problem that is encounter with the bougie use has been its difficulty navigating a patient's oropharynx. The physical properties of the bougie make it flimsy and bendable which can make it difficult for the medical personnel to control. The apparatus will be designed with a curved and enclave where the bougie is nested within. Once the bougie is nested within the apparatus there will be a latch that will secure the bougie to the apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a side planar view of a gripping device according to the present invention, with a bougie attached the device.
[0019] FIG. 2 is a side planar device shown in FIG. 1 .
[0020] FIG. 3 is a front perspective view of the device of FIG. 1 .
[0021] FIG. 4 is a front perspective view of the device shown in FIG. 1 with a bougie attached to the device.
[0022] FIG. 5 is a side planar view of the gripping device of FIG. 1 , with a hollow connector attached to the device.
[0023] FIG. 6 is a front perspective view of the device shown in FIG. 5 , demonstrating a suction control opening.
[0024] FIG. 7 is a front perspective view of the device shown in FIG. 6 , with a cap located on the suction control opening.
[0025] FIG. 8 is a rear perspective view of the device of FIG. 1 , with another arrangement of a hollow connector attached to the device.
[0026] FIG. 9 is a rear perspective view of the device shown in FIG. 6 , with a bougie connected to the device.
[0027] FIG. 10 is a front perspective view of the device shown in FIG. 9 , with a cap located on the suction control opening.
[0028] FIG. 11 is front perspective view of the device of FIG. 1 including a bougie, with means for locking the bougie within the device demonstrated.
[0029] FIG. 12 is another perspective view of the device as shown in FIG. 10 , with the device further supporting intubation tubing.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0030] 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.
[0031] As will be seen, the present invention overcomes many problems associated with prior art with intubation of a difficult airway, high risk of aspiration, or emergent endotracheal intubation. Upon induction of general anesthesia, unconscious patients, certain medical conditions render patients at risk for aspiration of gastric contents. Conditions like morbid obesity, diabetic gastroparesis, pregnancy, hiatal hernia, full stomach increases the risk aspiration upon induction of general anesthesia. The invention allows the operator to clear oral secretions, gastric contents, blood from the operator's field of view to safely intubate the patient.
[0032] FIG. 1 depicts an intubation control system 10 according to the present invention. The system 10 generally comprises a griping device 12 which is designed to encircle the length of a bougie 14 , which is used for intubation. The gripping device 12 has a top end 16 and a bottom end 18 , with a gripping surface 20 located on the outside of the gripping device 12 . An extension support area 22 extends from the gripping surface 20 , with the extension support area 22 also forming part of the gripping surface 20 . The gripping device 12 preferably has a curvilinear shape that will be shaped to assist in inserting the bougie 14 into a passageway.
[0033] FIGS. 2 and 3 provide further views of the gripping device 12 . The gripping device 12 further comprises an inner surface 24 and an exterior surface 26 . The inner surface 24 forms an opening to receive the bougie 14 . As previously noted, the inner surface 24 preferably comprises a curvilinear or longitudinally curved groove 28 shape, which can extend the length of the body. The inner surface may also comprise a semicircle shape, which will allow the bougie 14 to be nestled within the gripping device 12 and to be held in place within the gripping device 12 during an intubation process. The gripping device 12 is designed so that the bougie 14 can be forced into place by hand and, the bougie 14 will retain a curved shape with the curved groove 28 during a procedure.
[0034] Referring further to FIGS. 2 and 3 , the exterior surface 20 comprises a plurality of ridges 30 , which assist the user in gripping and properly holding and positioning the device 12 . The ridges 30 may comprise a semi-rigid material that would conform to a user's hand, but it is understood that the exterior surface 28 may comprise any surface or arrangement, e.g. a surface contoured for fingers or a rough or textured surface, that will assist in holding the device 12 .
[0035] Referring to FIG. 4 , the device 12 is shown with the bougie 14 nestled within the groove 28 . The proximal end 32 extends outward past the extension support area 22 , which will allow for the proximal end 32 to be eventually intubated. As shown, the proximal end 32 has an opening 34 , which allows fluid flow, e.g. air or oxygen flow, through the bougie 14 to distal end 36 of the bougie 14 . The control of fluid flow by using the device 12 is discussed further, below.
[0036] Referring to FIGS. 5 and 6 , the device 12 is shown comprising a connector 38 , which assists in fluid flow through a bougie 14 when using the device 12 . The connector 38 has a first end 40 and a second end 42 , with a hollow passageway passing from the first end 40 to the second end 42 , which allows the connector 38 to receive a bougie 14 (not shown) for fluid passage. For example, the connector 38 assists in passing oxygen through a bougie 14 , or for using the bougie 14 for suction purposes. The connector 38 may also comprise a suction control opening 46 , which intersects the hollow passageway in the connector 38 and allows for the user to manually control suction when the device 12 is in use.
[0037] FIGS. 5 and 6 also show another feature of the gripping device 12 that will assist in retaining a bougie within the gripping device 12 . A locking ring 48 is shown on the extension support area 22 . The locking ring 48 , e.g. a C-ring, can be rotated so that is will hold and retain a bougie 14 in place (see FIG. 10 ) during an incubation process.
[0038] FIG. 7 shows a further feature of the device 12 , comprising a cap 50 located on the suction control opening 46 . Such an arrangement allows for continuous suction and/or air flow, e.g. oxygen, through the bougie 14 . If manual control is required, the cap 50 can be removed.
[0039] FIG. 8 demonstrates a further arrangement of the device 12 shown in FIGS. 5 and 6 . The device 12 has the connector 38 located on the device 12 as previously shown and described. However, the first end 40 is perpendicular to the second end 42 , and the suction control opening 46 is parallel to the first end 40 . Such an arrangement may be preferable in certain instances and for certain uses. However, it is understood that the arrangements shown in FIGS. 5 and 8 operate in the same manner and can provide air or oxygen flow and/or suction as discussed, above.
[0040] FIG. 9 demonstrates the device 12 being used as a suction tool during an intubation process. As previously discussed, a bougie 14 is positioned within the device 12 . The proximal end 32 of the bougie 14 is shown extending past the extension support area 22 , with the opening 34 being arranged for eventual intubation. The distal end 36 of the bougie is then positioned and inserted into the first end 40 of the connector 38 . The second end 42 will be connected to an external fluid or air source (not shown), which allows the user to control suction control with the suction control opening 46 . The used controls suction by placing a finger on, by either right hand or left hand, or removing a finger from, the control opening 46 .
[0041] FIG. 10 demonstrates the device 12 being used for oxygen delivery. The arrangement is similar to that shown in FIG. 9 , with the exception that the cap 50 is located on the suction control opening 46 . The locking ring 48 is also shown holding the bougie 14 in place. FIG. 10 also demonstrates that the bougie 14 can form a one-loop coil, which further allows for the device 12 to provide an improved gripping arrangement for intubation procedures.
[0042] FIG. 11 further demonstrates the adaptability of the gripping device 12 . In FIG. 11 , the device is shown holding both the bougie 14 and an intubation tubing 52 . The device 12 can adapt so that both the tubing 52 and the bougie 14 can be nestled in the groove 28 , with the locking ring 48 being used, if necessary.
[0043] FIG. 12 further exemplifies the use of the gripping device 12 in connection with the intubation tubing 52 . The intubation tubing 52 is shown supported by the bougie 14 , with the gripping device 12 allowing the bougie in a coiled arrangement, as previously discussed. The arrangement also allows for the potential use of a balloon 54 , which may inserted along with the tubing into the trachea for certain procedures, and inflated by way of vent 56 , if necessary.
[0044] 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 embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims. | An apparatus for endotracheal intubation. The apparatus allows medical personnel to grip and stabilize a bougie inside the apparatus and maintain a curve position during intubation processes. The apparatus can be used for a solid bougie and/or a hollow bougie. The apparatus may further have a connector for connecting the apparatus to an external suction device or oxygen delivery device. | 0 |
PRIOR RELATED APPLICATIONS
This patent application claims the benefit of the priority of Argentine patent application serial number P100104972 filed on 28 Dec. 2010.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX
Not applicable.
BACKGROUND OF THE INVENTION
The present invention concerns tools for borehole applications, in particular oil wells, gas wells or water-wells, more particularly including installations for primary, secondary or tertiary oil production, whether holes for injecting water, gas or another pressurizing agent (injector holes) or oil extraction (production wells). A particular application of the tool is in injector and producer multi-zone wells where the number of isolation zones is high and/or the wellbore casing is damaged or diverted, to quickly and economically isolate areas with damaged casing.
The present invention applies to tools carrying a packer device comprising seals mounted to a mandrel and forming with other operational components a tubing string (or just “tubing”) of tools and components joined one after another for lowering down a multifunctional (or multizonal) well, i.e., having multiple layers or strata which should be isolated from one another. Packer tools are not unusual in the oil industry. The tubing string comprising a number of function-specific tools is lowered into a well, maintaining an annular space between and a well casing.
Packer tools generally comprise two basic elements: packer seals for isolating annular regions thereabove and below and anchor slips to affix the tool to a point of the casing. A packer sealing element is a ring made of metal and typically dense synthetic rubber that fits around the tubing in a well. The packer seal (the “packing element”) of a packer tool (the “packer”) is typically a rubber ring that expands against the side of the casing lining the side of the wellbore. A packer may, and usually will, have more than one packing element. In the majority of active wells in the world today, this tubing is used to either produce oil or gas out of the well and serve as a conduit to transport water into the well for water injection and water flood applications. The packer provides a secure packer seal between everything above and below where it is set. The main reasons for using a packer are to keep sediment, sand and other potentially corrosive or erosive materials from flowing into the annulus and damaging the casing, and to control the zone of the well from which hydrocarbons are being produced in a producer well or to control the zone where water is being injected in an injection well.
Slips hold the packer in place and prevent them from moving once they are set in the well. A slip is a serrated piece of metal that grips the side of the casing. Some packers lack a specific anchor device (in which case they are known as packer-tandems).
Insofar the present invention, the packer tool sequentially carries out the following phases:
Run-in: The tubing enters the well and the packer is lowered down to a set position.
Setting: Both the anchor slips and the packer seals are pushed outwards to respectively clamp the tool to the well during all the time the tubing stays down the well and isolate annular regions above and below the packer. The tool setting system may be mechanical, involving rotation or axial compression or traction, or else hydraulic by injecting a pressurizing fluid.
Release: This operation is carried out on removable tools to unset them from the well casing in order that they may be extracted. In tools having release systems, known as removable packers, release may be based on similar maneuvers or a combination thereof. Tools lacking a release system are known as permanent packers which need to be rotated to literally destroy the tool by machine milling. This operation is costly and time-consuming.
Extraction: The removable packer is hauled up to the mouth of the well.
The invention particularly relates to a packer tool that is removable, hydraulically set and mechanically released.
The present invention concerns the packer tool anchor means to the well casing wall by means of a dual-grip anchor device having bidirectional anchor slips, more precisely, the structural integrity of the anchor slips.
Use of mechanically- or hydraulically-actuated packer tools or, simply, packers for maintaining separation between production layers or fluid injection layers is well known in the oil industry.
The best known release systems are by rotation and traction. In the first system, the tool is released by rotating it several turns, which complicates the operation the deeper the well because of the greater number of tools. This in turn makes the operation unreliable through uncertainty regarding which tool is actually being operated.
In traction release, tractive tension is applied to the piping to shear a number of brass or steel pins. Once set, this kind of tool is subject to stress from temperature and pressure variations down the well, which get worse with increased depth to the point that pins may shear producing accidental tool release.
Also known in the art is to provide packer tools with an anchor device to affix the tool to the well casing wall for the duration in which the tool will remain inside the well for operations. U.S. Pat. No. 4,156,460 discloses a removable packer with two sets of separate sets of slips teeth with a seal device in between. Each set comprises four anchor slips at 90° from one another around mandrel. The upper set has its teeth facing upwards to selectively anchor the tool against upwardly movement whereas the teeth of the lower anchor slips face down in the opposite direction to selectively hold the tool against downwardly movement. Each set is engaged by its own actuator cone.
CA patent 2,286,957 illustrates the known concept of integrating the teeth of anchor slips in pairs, each pair consisting of one set of teeth directed against upward movement and another set of teeth directed against movement downwards, arranged side-by-side as a unit on a single piece, forming four anchor slips pieces which protrude through respective rectangular windows cut out in a cage, so as to share a single actuator cone. Moreover, this '957 CA patent suggests arranging the anchor slips at opposite ends of each anchor unit such that each anchor piece comprises an upper teeth member and a lower teeth member rigidly joined by a bridge forming part of the same unit.
This arrangement, which is also adopted in my prior AR patent publication 53,432 A1, is currently preferred and used in the present invention since it simplifies construction and operations. However, since the components of these types of tools frequently operate in extreme mechanical and thermal conditions, the anchor slips units are not free from becoming fractured during the tool run-in and dwelling time down a well.
The fracture of an anchor slip, aside from meaning potential problems for setting the tool, may also produce metal bits and pieces which may interfere with the movement of tool members such as during release operations and jam tool recovery. Pieces having substantial sizes may break off from the slips. The chance that a broken piece may interfere or jam an operation increases with the size of the broken-off piece. Slips fractures may occur near the bridge of the slips unit where the material properties transition, such that sizeable pieces or even an entire member may break off.
Furthermore, anchor slips may suffer damage in a well when beginning a release operation by turning the tool so that the release cone moves downwards to make room for the anchor slips to retract. Cone descent follows rotation of snugs formed on the mandrel that were retaining cone in its initial position and may be violent since it is driven by the weight of the cone itself, that of the lower sub depending from the cone and, more importantly, the load of the lower tubing components hanging from the lower sub of the tool.
The short and fast descent of the cone ends abruptly when a step thereof strikes a step formed at the bottom of the cage. The subsequent jar is transmitted to the anchor slips in the same and may fracture them.
Slips fracture causes randomly sized bits and pieces to come apart. Such broken pieces may get wedged in the annular space between the casing and some part of the tool such as the casing, troubling later attempts to haul the tool up, or fall inwards making release incomplete.
AR patent publication 41,393 (Reumann) discloses using an elastic means as a damper in a tool having a packing-holder collar and a wedge-shaped slips piece.
BRIEF SUMMARY OF THE INVENTION
An object of the invention is to provide a packer applicable to tools with dual-slips and hydraulic setting to overcome the above-mentioned prior art problems, thereby providing a packer having simple and reliable setting and release systems, converting it into a highly desirable tool for installations with multiple packers, useful for selective water injection, selective oil production or gas lift.
A particular object of the invention is to reduce the probability that an anchor slip may fracture as a result of jarring of the cage mounting the slips and, what could be more important still, in the event that a slip should break, reduce the probability that bits that have broken off and become separated from the main slip piece may interfere with operations for releasing the tool or extracting the tool from a well. A further object is to enhance the capacity of a fractured slip to carry out an anchor function.
The present invention overcomes the problem of fractured slip bits breaking off and separating by means of a linkage device which is separate from the bridge integrated with the slip. The separate linkage device links the pair of spaced-apart slip members to keep them together in the event of a fracture of a substantial part of the slip. This safety system against fractures provides more reliability to setting the tool since it means that the fractured bits will not move apart but will assist in anchoring the slips to the casing.
The linkage device is preferably embodied by a pair of stainless steel bars which are each lodged in a respective groove formed in the opposite sidewall of the slip. The ends of the bars are bent at right-angles and loosely anchored in blind holes formed in each slip member, the grooves extending from one blind hole to the other. In the event that a sizeable bit of a slip member should fracture, the fractured bit remains anchored by the linkage bars, thereby staying in place. Although in such an event it is foreseeable that the setting capacity of the fractured slip will not be the same, in any case some grip capacity to the casing may be provided in this way with this low cost solution of simple construction which, furthermore, prevents timely and costly problems when the time comes to release the anchor slips and raise the tool up and out of the well.
According to another aspect, the present invention reduces the intensity of the jarring to which the slips-holder cage is subjected to on account of it being met by the lower cone travelling downwards at the beginning of the release process. This is achieved, and potential damage to the anchor slips avoided, by inserting a resilient material to form a buffer between two complementary steps respectively protruding from the lower cone and the cage to dampen the effect of the free-falling cone hitting the cage.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings help to convey features of the present invention and advantages thereof by means of a preferred embodiment. In the drawings:
FIG. 1A is a view half elevation and half axial-section of a preferred embodiment of a packer tool according to the present invention, in an initial position ready for run-in;
FIG. 1B is a view analogous to FIG. 1A but with the tool in the set position;
FIG. 1C is a view analogous to FIGS. 1A and 1B but with the tool in the released position, ready for extraction, after its mandrel has turned 60°;
FIG. 2A is a magnified half-axial section view of the hydraulic mechanism of the packer tool of FIG. 1A with its chamber, piston and cylinder in the initial position for run-in;
FIG. 2B is a magnified view analogous to FIG. 2A but wherein the safety device guarding against premature setting has been disabled during the transition to setting the tool;
FIG. 2C is a magnified view analogous to FIGS. 2A and 2B but wherein the hydraulic mechanism has reached the final setting position and is stable;
FIG. 3A is a magnified half-axial section view of the packing mechanism of the packer tool of FIG. 1A in the initial run-in position;
FIG. 3B is a magnified view analogous to FIG. 3A except that the packing mechanism is now in the set position;
FIG. 3C is a magnified view analogous to FIGS. 3A and 3B but wherein the mandrel has been turned 60° to release the packing mechanism;
FIG. 4A is a magnified half-axial section view of the anchor mechanism of the packer tool of FIG. 1A in the initial run-in position;
FIG. 4B is a magnified view analogous to FIG. 3A except that the anchor mechanism is now in the set position;
FIG. 4C is a magnified view analogous to FIGS. 3A and 3B but wherein the mandrel has been turned 60° as in FIG. 3C to release the anchor mechanism;
FIG. 5A is a perspective view of the hydraulic mechanism of the tool of FIG. 2A wherein a quadrant of the view has been removed to show the annular segments of the antisetting mechanism in place in their initial position;
FIG. 5B is a perspective view analogous to FIG. 5A of the hydraulic mechanism of FIG. 2B showing relocation of the annular segments when setting is activated;
FIG. 6A shows the circumferential distribution of the annular segments which make up the antisetting safety mechanism of FIGS. 2 and 5 (alphabetic suffices are omitted from figure and reference numbers in the present description to indicate generalization), wherein some components such as O-rings have been omitted for the sake of clarity;
FIG. 6B is a cross-section of an annular segment of FIG. 6A ;
FIG. 7 is a magnified perspective view of part of the mandrel of the tool of FIG. 1 A showing two of the three anti-release safety pins located in their slots prior to the tool set position;
FIGS. 8A and 8B are respective section and plan views of one of the slots in FIG. 7 ;
FIG. 9 is a perspective view of an anchor slip unit with an anti-fracture device according to the present invention;
FIG. 10 is a magnified detail of a ratchet tooth impeding retreat of the packing device in FIG. 3B ;
FIG. 11 is a perspective view showing the geometry of the lower cone without slips and the bottom part of the mandrel that come into play for the release movement of the mandrel, and also showing the anti-resetting mechanism;
FIG. 12A is a cross-section of a typical bidirectional symmetrical anchor slip;
FIG. 12B is a cross-section analogous to FIG. 12A of an asymmetrical anchor slip having one set of typical teeth and one set of dummy teeth.
In all the figures like reference numbers identify like tool parts.
DETAILED DESCRIPTION OF THE INVENTION
A packer tool or “packer” having a nominal diameter of, e.g., 5½″ (139 mm) is depicted in FIG. 1A (notwithstanding that the invention may encompass other standard tool sizes such as 7″, 9⅝″, etc.). The packer includes a mandrel 11 made of ASTM A519 steel type 4140-Y80 crowned, above, by an upper sub 12 and, below, by a lower sub 13 . The three components 11 , 12 and 13 are made of SAE 4140 tempered steel and, together, span a tool length of about 1.4 meters. A central bore 14 about 50.8 mm (2″) in diameter axially traverses the mandrel 11 .
The upper and lower subs 12 , 13 are provided with threaded joints for connecting other tubing components above and below prior to the run-in operation. This arrangement allows torque to be transmitted down the length of the tool and, during run-in down a well, allows maneuvering of the entire tubing.
About the mandrel 11 and between the subs 12 and 13 the tool further includes, from top to bottom, a hydraulic mechanism 15 depicted in FIGS. 2A , 2 B and 2 C for setting the tool, a packing mechanism 16 depicted in FIGS. 3A , 3 B and 3 C for isolating well layers and an anchor mechanism 17 depicted in FIGS. 4A , 4 B and 4 C for keeping the tool affixed to a point in the well while it dwells therein.
The hydraulic tool setting mechanism 15 of FIG. 2A comprises a hydraulic piston 18 arranged around the upper part of the mandrel 11 to carry out a downward movement during the set operation. The piston 18 is surrounded by a hydraulic cylinder 19 at the top of which a hanger cap 21 is screwed on to prevent it from descending. The piston 18 functions as an actuator during the set operation, when in moves downwards to the position depicted in FIG. 2B to activate the packing and anchor mechanisms 16 - 17 as described further on hereafter.
A hydraulic chamber 22 is formed about the top of piston 18 to receive pressurized fluid for activating setting through passages 23 that communicate it with the central bore 14 of the mandrel 11 . The hydraulic chamber 22 is closed in by the upper sub 12 , the mandrel 11 , the hydraulic cylinder 19 , the piston 18 and packer seals 24 .
Shear pins 26 screwed into the hydraulic cylinder 19 and penetrating through to a slot or depression 27 formed on the outer surface of the piston 18 convey reliability to the setting operation by preventing the latter from moving downwards in absence of sufficient hydraulic pressure in the chamber 22 . To proceed with the set operation once the tool has been run-in down the well, fluid is injected at a predetermined pressure from the mouth of the well into the mandrel bore 14 such that it enters the radial passages 23 and fills the chamber 22 . The effect of this pressure is to urge the piston 18 downwards to the position depicted in FIG. 2C as described further on herein, after shearing the threaded pins 26 which are dimensioned to said predetermined setting fluid pressure.
In this embodiment, the threaded pins 26 are made of brass, ¼″ (6·35 mm) in diameter and the setting pressure is predetermined according to the number of threaded pins 26 , e.g., 400 psi (2.8 MPa) per pin 26 . The piston 18 and its threaded pins 26 are protected from damage by the hanger cap 21 during upward maneuvering of the tubing through zones of restricted diameter in the casing.
However, I have seen that during run-in the pins 26 may be exposed to shear forces in absence of hydraulic pressure, caused by a calibrating ring 28 on a joining member 29 scraping or striking against the inner casing wall and transmitted up by the hydraulic piston 18 and the hydraulic cylinder 19 . Shearing of the threaded pins 26 brings about the risk of the piston 18 prematurely sliding downwards and accidentally activating the packing and anchor mechanisms 16 - 17 . This risk is avoided by means of an antisetting safety mechanism which prevents any downward movement of the piston 18 on the mandrel 11 in absence of the required setting activation hydraulic pressure. This safety mechanism is embodied by a ring segmented into three parts 31 arranged equi-circumferentially in slots in the piston 18 as depicted in FIGS. 5A and 6A . FIGS. 6A and 6B show the preferred shape and proportions of these annular segments 31 .
The annular segments 31 protrude radially inwards from the piston 18 fitting into a circumferential slot 32 formed on the outer wall of the mandrel 11 about 10 mm wide and chamfered edges as do the annular segments 31 too (more clearly visible in FIG. 6B ) so as to retain the piston 18 . At the same time, the hydraulic cylinder 19 acts as a “roof” that prevents the segments 31 from leaving the slots 32 in the mandrel 11 . As a consequence, the piston 18 may not exert a force necessary to shear the threaded pins 26 to enable tool setting. The only way the segments 31 may leave the slot 32 and free the piston 18 is for the cylinder 19 to rise so that the complementary geometries of the cylinder 19 and the piston 18 create a space 33 , as may be seen in FIG. 2B , sufficient for the segments 31 to leave the slot 32 , as may be seen in FIG. 5B , and free the piston 18 . However, the cylinder 19 may only budge by effect of the hydraulic pressure in the chamber 22 , since the safety pins 26 prevent any undue ascent thereof. This segmented ring 31 system facilitates tool travel through zones of the casing where the diameter is restricted, without the tool setting prematurely.
The segmented ring 31 has a small circumferential notch 34 on its outer cylindrical surface and which continues around the intervening mandrel surface for a retainer ring 36 that softly maintains the annular segments 31 in place through the piston 18 and in the slot 32 when putting the tool together. It is an open ring 36 of relatively thin wire which easily yields and opens when pushed outwards by the annular segments 31 as soon as the latter are freed by the ascending cylinder 19 . Suitable dimensions for the open ring 36 are about 1.75 mm in wire diameter, about 77.0 mm and about 80.4 mm inside and outside diameters, respectively, of the ring 36 and 5 mm separation between its open ends 37 when relaxed.
FIG. 3A shows the packing mechanism 16 comprising three rubber packer seals 38 made of NBR (Nitrile Butadiene Rubber) elastomer, separated by sliding spacer rings 39 and mounted to a seal-holder collar 41 which is engaged by the piston 18 via the joining member 29 . The joining member 29 has a calibrating ring 28 screwed thereon to adjust the amount of deformation of the packer seals 38 into the annular space between the tool and the casing during the set operation. The section of the packer seals 38 includes a chamfered surface 42 which emerges first in response to pressure applied by the joining member 29 , as FIG. 3B illustrates, so that a circumferential lip 43 makes first contact and continues to deform against the inner wall of the casing to form a hermetic seal. Once in the set position, the packer seals 38 remain pressed against the casing wall, blocking passage of fluids from one side to the other of the packing 38 in the axial direction of the well.
Three anti-release safety pins 47 are fitted in round holes 46 perforating the seal-holder collar 41 . Each pin 47 is made of SAE4140 tempered steel and is formed with a cylindrical or slightly frustoconical stud 48 about 11.0 mm in diameter and about 4.5 mm length and a head 49 which is also cylindrical but larger both in length and section as FIG. 7 shows, measuring about 19.5 mm in diameter and about 15.5 mm long, forming a smooth piece which is highly resistant insofar it is dimensioned so that the head-stud 49 - 48 transition is be virtually unyielding to shear forces. The head 49 fits snugly in the round orifice 46 through the packing-holder collar 41 and the stud 48 in a respective longitudinal slot 51 machine-cut in the mandrel 11 as illustrated in FIGS. 8A and 8B . The slot 51 is about 29 mm long, about 12 mm across and about 4.3 mm high in the illustrated embodiment.
Since these pins 47 are smooth, a cylindrical cover 52 is provided to retain them and prevent them from falling out of the orifices 46 . In turn, the cover 52 is held in place by three stud bolts 53 screwed on to an upper superior 56 forming part of the anchor mechanism 17 , which detailed further on hereinafter.
In FIGS. 3A and 7 , the studs 48 of the pins 47 are constrained by the corresponding machine-cut slots 51 , thereby locking the mandrel 11 against rotation in relation to the combined packing-anchor mechanisms 16 - 17 (and, hence, relative to the well). The smooth anti-release pins 47 further prevent relative rotation between the tool ends, that is between the subs 12 and 13 , thereby conveying greater reliability to connection and rotation operations on the upper and lower tubing components during mounting at the mouth of the well and later run-in.
When the piston 18 advances downwards to activate tool setting, the axial downwardly displacement of the seal-holder collar 41 moves the studs 48 of the pins 47 out of these slots 51 , as seen in FIGS. 3B and 8 , such that they now have room to turn on the mandrel 11 . As described further hereafter, the release movement is based on a rotation of the mandrel 11 relative to the combined mechanism 16 - 17 , such that the smooth pins 47 prevent accidental occurrence of the release turning movement if the tool has not been previously set. This means that reliability against accidental release depends no more on a single shear-pin release system such that pressure variations which appear either inside or outside the tubing do not affect proper operation of the anchor slips nor of the packing seals mechanisms 16 - 17 any more.
FIG. 4A shows the mechanism 17 of the packer tool for anchoring the tool, comprising: upper and lower cones 56 and 57 , individually slidable axially downwards to respectively activate tool setting and release, anchor slips 58 equi-circumferentially distributed around the mandrel 11 and slidable on ramps 59 machine-cut in the cones 56 and 57 , and a slips cage 61 with individual windows 62 through which the anchor slips 58 may project. This 5½″ diameter tool set forth herein by way of example has three anchor slips 58 arranged at 120° from one another around the mandrel 11 although larger tools may have four or five anchor slips 58 . Each anchor slip generally has a pair of horizontal and parallel teeth sets 63 with sharp edges 64 that bite into the casing wall in the set position and hold the tool fast. Each set 63 spans an outer cylindrical face measuring 60 mm×46 mm on a slip member 66 (alphabetical suffices A, B . . . are omitted when the reference is general), each pair of members 66 of a given slip 58 being longitudinally spaced from and joined to one another by a bridge 67 , all integrated into a single slip piece made of cemented SAE 8620 steel.
The anchor slips 58 are initially retracted inside the cage 61 where they are protected during the run-in. The setting operation involves pushing the anchor slips 58 out of the windows 62 to contact the casing wall. In spite of precautions, the anchor slips 58 may suffer damage anyway from different excessive mechanical or thermal conditions to which the tool is exposed during the run-in and, specially, during the lengthy period it dwells inside a well.
Failure of an anchor slip 58 may cause its teeth 64 to lose grip on the casing wall and the broken anchor slip to fall back inwards. The eventual loss of contact of an anchor slip 58 loosens the pressure of the remaining anchor slips on the casing wall, which may eventually lead to ineffectual setting of the tool.
To prevent this event, according to a feature of the present invention, a pair of external linkage means 68 separate from the bridge 67 and having different structural and mechanical properties are placed along each side of each anchor slips 58 and its end are connected to slip members 66 as shown in FIG. 9 . Each link 68 is a steel bar 68 of stainless steel—such as SAE 1020—for greater ductility, having a cross-section of 2 mm 2 and its ends are bent 90° and inserted in holes 69 made in each slip member 66 . The sidewalls of the slips 58 have grooves 71 for housing the linkage bars 68 and keep them in the holes 69 of the anchor slips 58 . In this way, the cemented steel material contributes its typical hardness to anchor slips 58 and the external linkage bars 68 relative ductility less prone to failure from jarring and thermal excursions which may fracture an anchor slip 58 .
The bridges 67 of the slips 58 are not thermally treated and hence remain ductile. First, the entire piece 58 is cemented, then only the region of the teeth 63 is induction- or flame-heated and the entire piece 58 is tempered. In this way, the slips 58 are hard in the region of the teeth 63 and ductile in the region of the bridge 67 so that, in spite of the latter being the narrower part of the piece 58 , a fracture is more likely to occur in the region of the slip members 66 . As a result, should a substantial part of an anchor slip 58 fracture, the bars 68 will keep the members 66 linked together preventing the broken part from separating. This provides a two-fold advantage of keeping the slip members 66 together and avoiding a big broken slip part from getting in the way of tool operations such as preventing the tool from setting properly. In addition, the loose insertion of the linkage bar 68 ends in the slips member holes 69 provides some articulation as opposed to the rigidness of the bridge 67 connection.
Resuming the description of the setting operation, the pressure inside the hydraulic chamber 22 generates two opposing forces, one upwards and the other downwards. The former acts on the hydraulic cylinder 19 , pushing it upwards, and the downward force on the hydraulic piston 18 , urging it downwards. These opposing forces shear the safety pins 26 and enable the hanger cap 21 and the hydraulic cylinder 19 to lift. The annular segments 31 are thereby free to leave the slot 32 in the mandrel 11 , unrestraining the piston 18 . As the piston 18 starts sliding downwards driven by the pressure in the hydraulic chamber 22 , after the three ring segments 31 have been freed as shown in FIG. 2B , it pushes the rubber seals 38 downwards. Before deforming substantially as shown in FIG. 3B , the seals 38 transmit this force via a lower calibrating ring 72 to the upper cone 56 which, in turn, forces the slips 58 outwards in a direction perpendicular to the tool axis. This is as a result of the direction of movement being changed from axial to radial by the upper cone 56 wedging under the upper members 66 A of the slips 58 which have an inner surface 73 in the shape of a curved ramp. The radial slip expansion continues until it reaches the inner diameter of the casing with a force that sets the packer tool in the position depicted in FIG. 4B . A wedge-shape 74 formed on the lower slip member 66 B is concurrently forced up a cylindrical ramp 76 on the lower cone 57 and also assists in pushing the slips 58 outwards. The lower cone 57 is provided with three stops 77 spaced equi-circumferentially on its bottom edge which abut against three snugs 78 formed on the surface of the mandrel 11 . In the preferred embodiment, the cone ramps 73 y 76 and the slip 66 wedges have inclinations of approximately 20° relative to the axial direction and the snugs 78 define an imaginary outer diameter of 82.5 mm. Once the slips 58 are set, the upper cone 56 may descend no more such that the entire axial force from the still down-moving piston 18 now compresses the seals 38 , expanding their diameters and causing them to seal against the casing.
As the piston 18 moves down it also drives an open ring 79 downwards. The open ring 79 is provided with sawtooth-like inside teeth 81 which mesh with matching ratchet teeth 82 carved on the mandrel 11 in the path of the ring 79 . The meshing teeth 81 - 82 which define a ratchet are formed by reverse-tap screws having 16 threads per inch (pitch=1.588 mm) on the ring segment 79 and the mandrel 11 . FIG. 10 illustrates the geometry and dimensions in millimeters of the anti-retreat teeth 81 formed on the ring segment 79 . This ratchet prevents the piston 18 from retreating back up and enables the tool to remain properly set and sealed once the hydraulic chamber 22 has depressurized, hydraulically isolating the upper and lower parts of the tool. FIG. 2C indicates the end positions of the lowered piston 18 and of the raised hydraulic cylinder 19 after the fluid has evacuated the chamber 22 .
As with the upper calibrating ring 28 , the dimensions of the lower calibrating ring 72 can be adapted to individual well conditions.
Accordingly, in this preferred embodiment, the setting mechanism—the first fundamental operation in a useful cycle of a tool of this type—essentially comprises the hydraulic chamber 22 , the hydraulic cylinder 19 , the piston 18 , the joining member 29 with its calibrating ring 28 , the three rubber packer seals arranged about the seal-holder collar 41 of the packing mechanism 16 , the cylindrical cover 52 , the upper cone 56 and the three anchor slips 58 .
The second fundamental operation in the tool cycle is release, which consists in moving the lower cone 57 retained by the snugs 78 downwards to allow retraction of the anchor slips 58 and the rubber packer seals 38 . Tool release begins by effectively rotating the tubing 60° to the right. The necessary torque for the mandrel 11 to rotate is given by the number of shear pins 83 screwed into the lower sub 13 which holds the mandrel 11 fast to the lower cone 57 and the lower sub 13 .
The release torque applied to the mandrel 11 from above the well first shears the safety pins 83 dimensioned to break when subject to the release torque, thereby enabling the mandrel 11 to turn inside the lower cone 57 thereby displacing the mandrel snugs 78 from their position against the stops 77 of the lower cone 57 , as may also be seen clearly in FIG. 11 , to a position where the stops 77 face spaces 84 formed between the mandrel snugs 78 , enabling the lower cone 57 to drop about 130 mm (5″) together with the lower sub 13 , sliding along the mandrel 11 to thereby trigger quick release of the tool. The guide snugs 78 of the jay 86 , which come out from their locking position during setting and are guided down the slots 84 cut out in the lower cone 57 to their release position, do so without torsionally uncoupling the mandrel 11 from the lower sub 13 , thereby maintaining release control over the tool torque throughout the tool.
During the downward displacement of the lower sub 13 , a notch 87 is uncovered in the jay 86 of the lower cone 57 , allowing pressures to equalize inside the tool and in the annular spacing. This situation enables forced circulation of clean fluid between the tubing and the annular, and towards the surface to wash the length of the tool.
The lower cone 57 has a step 88 which, as the cone 57 slides down the mandrel 11 , strikes a complementary step 89 formed in its path on the slips cage 61 , dragging it down together with the anchor slips 58 . As the lower cone 57 descends, the anchor slips 58 loose their foothold on the lower cone 57 and slide along the ramp 76 thereof allowing the anchor slips 58 to retract again against the mandrel 11 . The packer thus becomes unset from the casing. The upper cone 56 also descends a short distance, enough to decompress the rubber packer seals 38 , such that the radial length increases again at the expense of a diminishing diameter and become unsealed. The tool is thus fully released regarding both the anchor and packing mechanisms 16 - 17 .
Since pressure conditions down the borehole as well as mechanical friction during tool extraction could push the lower cone 57 back upwards after release, spontaneously resetting the tool sufficiently to impede extraction or otherwise make it more difficult, a restrainer is provided against eventual retreat of the release mechanism. The release mechanism essentially comprises the lower cone 57 and associated means that control and participate in the downward movement just described hereinbefore. This restrainer prevents the lower cone 57 from sliding upwards back along the mandrel 11 thereby avoiding another setting post tool release. The anti-post-release-resetting restrainer comprises an expansible ring 91 around the mandrel 11 housed inside a small triangular recess in the inner surface of the lower cone 57 to define a transversal step 93 . When the cone 57 slides downwards, it drags the restrainer ring 91 down with it until the latter lodges in a circumferential notch 94 formed on the wall of the mandrel 11 , as FIG. 4C illustrates, transforming the ring 91 into a safety lock which prevents the lower cone 57 from being able to move back up again under any circumstance once the ring 91 penetrates the notch 94 . Hence, the tool may be reliably handled once released.
In this preferred embodiment, the restrainer ring 91 is about 4 mm thick and about 8 mm wide whereas the depth of the notch 94 reduces this part of the diameter of the mandrel 11 down to about 67 mm (2.6″). This measurement is a trade-off between the need of sufficient notch depth to catch the ring 91 without unduly weakening the wall thickness of the mandrel 11 .
As in the setting maneuver, the complementary steps 88 - 89 become axially apart as illustrated by FIG. 4B and meet again as the lower cone 57 comes down in a manner which sometimes may be hard enough to fracture the anchor slips 58 . As mentioned hereinbefore, broken slips bits are a risk factor which may interfere with the release process. According to an aspect of the present invention, a buffer or damper means formed by a rubber ring 96 is located between the pair of steps 88 - 89 . Preferably, the ring 96 is made of acryl-nitrile D-90 and has a square or rectangular cross-section of about 6.7 mm wide and about 94.3 mm and about 105 mm inner and outer diameters, respectively.
Describing the anchor slips 58 in greater detail, FIG. 10A exhibits a typical, bidirectional anchor slip 58 having gripping teeth 64 shaped in a triangular cross-section slanted towards a preferred orientation, i.e. like a saw-tooth, in order to oppose substantial frictional resistance against a prevailing axial direction against the casing of the well, compared to the opposite direction. In each typical anchor slip 58 , the preferred slant direction of the teeth 64 of one set 63 is opposite to the other so as to maximize the tool setting power against the casing wall by virtue of both sets of oppositely slanted teeth 63 forming part of the same rigid piece 58 . In the embodiment illustrated in FIGS. 4A , 4 B and 4 C, the upper teeth 63 are set against descent and the lower teeth 63 against ascent.
One (and most preferably not more than one) of the anchor slips 58 ′ comprises unidirectional teeth 64 in one set and “dummy teeth” 97 as the other. The latter are characterized by blunt rather than sharp edges 64 , for instance by termination in rounded edges 98 when compared to the sharp teeth 64 of the rest of the anchor slips 58 . In addition, the “dummy teeth” 97 furthermore lack a preferred orientation of the teeth 97 , rather they are symmetrical, i.e. not slanted, as FIG. 12B shows, in contradistinction to the typical teeth 64 with a preferred orientation shown un FIG. 12A . I estimate that the radius of the cylindrical curvature of the rounded edges 98 should not be less than about 0.4 mm, preferably not less than about 0.8 mm, to meet the object of the invention. In other words, the set of dummy teeth 97 opposes scant resistance in either axial direction against sliding along the casing wall.
This overcomes the potential problem of the teeth 64 “merging” or “integrating” with the casing after a long period of being together in the same biting position. What happens is that, as an anchor release operation begins, the typical set of teeth 64 which partner the set of dummy the teeth 98 becomes unstuck freely and separates from the casing promoting immediate collapse of the typical-dummy pair 58 ′ such that this slip releases first. The loss of a bearing point of the packer tool provides a degree of freedom for transversal movement of the tool to release the two remaining anchor slips 58 with no difficulty.
On the other hand, the “dummy” teeth 98 carry out a secondary function by applying a radial force on the casing wall which balances out the radial forces exerted by the “typical” teeth 64 angled at 20°.
These features convert the packer of the present invention into an efficient and reliable tool during run-in, setting and release, applicable to well completions requiring lowering, affixing and recovering multiple packers in a single voyage of the tubing, such as in water injection and in hydrocarbon production installations. The mandrel 11 in combination with the lower sub 13 may function as a telescopic joint assuring that movements applied to a particular tool which is being operated are not transmitted to tools located therebelow.
A particular embodiment of the invention has been disclosed herein, however changes in materials, shapes, sizes, geometry and arrangement of tool components may be carried out without departing from the purview of the present invention as set forth in claims that follow. For instance, a packer tool having a nominal diameter of 7″ or 9⅝″ may comprise more than three slips. | A linkage device separate from the integrated slips bridge links the pair of spaced-apart members of each slip to prevent sizeable fractured bits from moving away in the event of a fracture in the slip. The linkage device comprises a pair of ductile steel bars the ends of which loosely anchor in holes in each slip member, the holes being located at both sides of the slips at opposite ends of a groove that houses the linkage bar preventing it from falling out of the holes. In this way, a fractured slip may continue to assist in setting the tool and, moreover, potential hazardous interference in further tool operations are avoided. Furthermore, tool damage including slips fracture is reduced by a resilient damper material which buffers the lower cone as it slides down on the slip-holder cage during a tool release operation. | 4 |
FIELD OF THE INVENTION
[0001] This invention relates generally to creped paper. More particularly, it relates to creped tissue paper such as facial tissue and bathroom tissue products, and processes for producing such products and other forms of crepe paper.
DESCRIPTION OF THE RELATED ART
[0002] Tissue products such as facial tissues, toilet tissues and absorbent towels are well-known in the art and widely used. The softness properties of such paper products is of utmost importance, and can be conferred upon paper via many mechanical and chemical means. “Creping” and “Through-Air-Dry” (TAD) usually refer to the mechanical means for achieving softness, and the chemical means are carried out by inclusion of de-bonders and/or softeners during the normal processing of pulp and paper used to make such products. In addition to conferring softness properties, creping processes generally increase the absorbency of such paper products by increasing the void volume in the sheet.
[0003] In a popular conventional process of making tissue, the wet web (60-65% moisture) is conveyed to the dryer by means of a felt, and is subsequently transferred to a drying cylinder which is commonly referred to as a “Yankee” dryer by those skilled in the art, at a pressure nip. The surface temperature of the dryer is often very near 100° C., and machine speeds in the range of 800 to 2000 m/min are common. Creping paper involves spraying the dryer cylinder with a suitable amount of adhesive via a spray boom at its 6 o'clock position ( FIG. 1 , below) and pressing the paper web against the surface of the dryer cylinder. The sheet is dried as it travels around the circumference of the dryer and is subsequently removed from the dryer surface by a metal “doctor” blade. This action ruptures some fiber-to-fiber bonds within the webs, and causes the web to expand somewhat and become soft.
[0004] At the time of creping, the sheet contains about 5% moisture. A loop structure within the paper called a microfold is formed as the doctor blade removes the sheet. Subsequently, other loops or microfolds form on top of the first one creating a pile or macrofold. The degree of the effects of the creping process depends on factors such as the strength of the adhesive (i.e., the degree of adhesion of the sheet to the dryer), the difference in speed between the Yankee dryer and the final selection of the paper machine, doctor blade geometry, and the raw fiber materials used in the stock. Inadequate adhesion of the sheet to the dryer surface will result in inferior quality, and possible problems at the reel such as wrinkling, Holdovers, and weaved edges.
[0005] An effective chemical creping aid must provide a uniform tacky coating across the entire face of the dryer so that the sheet is evenly adhered to the surface of the dryer. High levels of adhesion of the paper web to the dryer will cause the web to dry faster, enabling higher energy efficiency and higher speed operation. In addition to proper adhesion, a coating of a thin layer of organic and inorganic material deposited on the dryer by the action of the evaporation of the water serves to protect the dryer and blade surfaces from excessive wear. While some amount of buildup of the creping aid on the surface is necessary, excessive buildup can cause humps, wrinkles, or holes in the sheet.
[0006] Another important characteristic of an effective creping aid is that it be re-wettable. “Re-wettability” refers to the ability of the adhesive film remaining on the Yankee dryer surface to be activated by absorbing water from the fresh application as well as from the moisture which is released from the fibrous structure at the pressure roll nip of the Yankee dryer. Re-wettability is an important property of an effective creping aid as only very small amounts of adhesive are added per revolution of the Yankee dryer.
[0007] Recently, drying of the web by the “throughdrying” or “through-air” method has received considerable attention because it improves bulk and softness of the web during drying. In such a process, hot air is passed through the web to effect partial drying prior to pressing the web against the Yankee dryer to finish the drying process. However, one disadvantage of partial drying prior to the dryer is that the resulting partially dried web requires the addition of a creping adhesive to the surface of the dryer in order to provide adequate adhesion of the web to the cylinder necessary to obtain proper creping. This was not required in some conventional processes in which the high moisture content of the web provides sufficient adhesion of the web to the dryer.
[0008] Polyamide polyamine epichlorohydrin (PAE) resins derived from secondary amine have been found to be effective creping aids in paper machine systems using the conventional wet press section. However, they are not efficacious in the paper machine systems which employ through-air drying. Creping aids derived from polyaminoamide (“PAA”) secondary amine resin chemistry are also efficacious; however, insomuch as they are thermosetting, they have a tendency to cure on the heated surface of the dryer. As a result, the coating formed on the dryer using through-air drying tends to be brittle, and exhibits poor adhesion of the sheet to the dryer surface. Additionally, the thermosetting wet strength resins will crosslink with creping aids which contain a secondary amine backbone, causing the formation of a hard coating on the surface of the dryer with poor adhesion characteristics. As a result, specialized thermoplastic resins have been developed to diminish these problems.
[0009] Poly(aminoamide)-epichlorohydrin (PAE with secondary amine) resins are commonly used as creping aids, as described in U.S. Pat. Nos. 5,388,807, 5,786,429, 5,902,862 and Canada Patent No. 979,579, the entire contents of each of which each of these, and all other patent documents cited in this specification, are herein expressly incorporated by reference thereto. These resins prove to exhibit good adhesion; however, since they are thermosetting, upon heating they will eventually cross-link and irreversibly harden. As a result, the addition of moisture is no longer able to soften the coating sufficiently to optimally bond with the web at the pressure roll nip. In other words, their re-wettability is poor. To improve the wettability, PAE is combined with polyvinyl alcohol (PVA), and a synergy is observed for the mixture (U.S. Pat. No. 4,501,640 and U.S. Pat. No. 4,528,316). PVA is known to exhibit a re-wet mechanism and has been claimed as a creping aid (U.S. Pat. No. 3,926,716); however, PVA alone is not as effective as PAE. Since PAE resins contain a relatively high content of chloride ion, they eventually will corrode the dryer surface. Another problem associated with PAE resins is the coating buildup.
[0010] U.S. Pat. No. 5,179,150 discloses a creping composition comprising (a): a thermosetting glyoxylated vinyl amide polymer (e.g., glyoxylated acrylamide/DADAMAC co-polymer) and (b) polyvinyl alcohol.
[0011] U.S. Pat. No. 5,187,219 discloses a thermosetting creping aid comprising glyoxylated vinyl amide polymers (e.g., glyoxylated acrylamide/DADAMAC co-polymer) in combination with polyols as plasticizers. The polylols are compatibles with the polymers and they form a uniform coating.
[0012] U.S. Pat. No. 6,214,932 discloses a creping adhesive comprising a mixture of polyamide derived from a dibasic acid (e.g., adipic acid) and polyalkylene polyamine (diethylene triamine) and polyvinyl alcohol and reacting this polymer mixture with epichlorohydrin. This particular crepe aid exhibits better adhesion than the physical blends of polyamide resin with polyvinyl alcohol as disclosed in U.S. Pat. Nos. 4,501,640, 4,528,316, 4,784,439, and 4,788,243.
[0013] U.S. Pat. No. 5,490,903 discloses a creping adhesive which contains a blend of an ethoxylated acetylenic diol surfactant, polyaminoamide, and polyvinyl alcohol. The dynamic surface tension is shown to be less than 40 dynes/cm at 5 bubbles/sec. As a result, more uniform coating is achieved, as described therein.
[0014] U.S. Pat. No. 5,833,806 discloses a creping composition which contains (a) a polyamine epichlorohydrin or polyaminoamide epichlorohydrin resin and (b) a release agent that is a plasticizer for the above resin, e.g., ethylene glycol, triethanolamine.
[0015] U.S. Pat. Nos. 4,684,439 and 4,788,243 disclose an improved wettable creping adhesive comprises a mixture of PVA and water soluble thermoplastic polyamide resin which is the reaction product of a polyalkylene polyamine (e.g., diethylene triamine), a saturated aliphatic dibasic carboxylic acid (e.g., adipic acid), and a poly(oxyethylene) diamine (e.g., JEFFAMINE® ED 600 polyetheramine).
[0016] U.S. Pat. No. 5,370,773 discloses a creping adhesive comprising (a) a non-self crosslinkable polymer (e.g., polyvinyl alcohol); (b) multivalent cation crosslinking agents; and (c) phosphate surfactant as an internal lubricant to improve creping blade wear and protect the dryer from corrosion.
[0017] U.S. Pat. No. 4,440,898 discloses a creping adhesive for use in a throughdrying process comprising mixture of an ethylene oxide/propylene oxide co-polymer and a high molecular weight thermoplastic polymer selected from the group of polyvinyl alcohol and polyvinyl pyrrolidone.
[0018] U.S. Pat. No. 4,886,579 discloses a method of applying the creping adhesive comprising 10-100% by weight of a polymer or co-polymer having a glass transition temperature greater than 50° C. (e.g., polymethyl acrylate) to the web prior to its contact with the creping surface.
[0019] U.S. Pat. No. 4,994,146 discloses a creping method in which a water soluble polyacid such as polyacrylic acid (not polyacrylate), styrene maleic acid co-polymer, mixture of polyvinyl alcohol and polyacrylic acid is applied to the surface of the cylinder and a second water soluble polymer selected from polyether (e.g., polyethylene oxide), polyacrylamide is applied to the surface of the web. When the two components are in contact at the pressure roll nip, an adhesive complex is formed.
[0020] U.S. Pat. No. 5,234,547 teaches a creping adhesive which contains an anionic co-polymer of acrylamide and acrylic acid.
[0021] While the materials and processes of previous workers in this field have attempted to provide materials which satisfy all of the requirements of the processors of crepe papers, each is not without its own shortcomings, the most common of which are cost, corrosiveness to equipment, and ease of use and maintenance of mill equipment.
[0022] The co-polymers of the present invention have a low glass transition temperature, are not corrosive to the dryer or other equipment, are relatively low in cost to produce, and have been found to be extremely effective at enhancing the quality of crepe paper, which makes them the model materials for this employment as of this writing.
SUMMARY OF THE INVENTION
[0023] The present invention provides a composition of matter useful in the creping of paper products such as facial tissues and bathroom tissue which comprises: a) water; and b) an alkanolamine salt of a styrene-methacrylic acid co-polymer. The salt is preferably made by combining an alkanolamine with a styrene-methacrylic acid co-polymer. The co-polymer has a styrene content in the range of between 10.00% and 90.00% by weight based upon the total weight of said co-polymer, and a weight-average molecular weight in the range of between 3,000 and 500,000. According to one form of the invention, the alkanolamine is selected from the group consisting of: mono-alkanolamines; di-alkanolamines; and tri-alkanolamines. The alkanolamine preferably includes at least one C 1 to C 14 alkyl chain bonded to a nitrogen atom, wherein the alkyl chain further includes at least one hydroxy group bonded to one of the carbon atoms in the alkyl chain. Two or three such “hydroxy alkyl chains” may be bonded to the nitrogen atom in alternate forms of the invention.
[0024] In another embodiment, the present invention comprises a composition as previously stated, and further comprises cellulose fibers.
[0025] The invention also provides a process for creping tissue paper, comprising: contacting an adhesive to the dryer used in the manufacture of tissue paper, wherein the adhesive comprises an aqueous dispersion comprising any amount of water in the range of 60% to 99.9% and from about 40% to about 0.1% solids. The solids comprise an alkanolamine salt of a styrene-methacrylic acid co-polymer having a styrene content in the range of between 10.00% and 90.00% by weight based upon the total weight of the co-polymer, and a weight-average molecular weight in the range of between 3,000 and 500,000. The alkanolamine is selected from the group consisting of mono-alkanolamines; di-alkanolamines; and tri-alkanolamines. The alkanolamine includes at least one C 1 to C 14 alkyl chain bonded to a nitrogen atom, wherein the alkyl chain further includes at least one hydroxy group bonded to one of the carbon atoms in the alkyl chain. A tissue paper web is caused to be adhered to the surface of said dryer; and is subsequently removed from the dryer via a doctor blade.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In the annexed drawings:
[0027] FIG. 1 shows a schematic diagram of a creping process; and
[0028] FIG. 2 shows the influence of various treatments on adhesion force.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The present invention is directed at compositions of matter useful as creping additives. A composition according to a preferred form of the invention comprises an amine salt of styrene-methacrylic acid co-polymer, in which the co-polymer has a styrene content from about 10% to about 90% by weight based on the total weight of the co-polymer. The molecular weight of the co-polymer is preferably in the range of 3000 to 500,000 weight-average molecular weight (all molecular weights disclosed in this specification are weight-average molecular weights, unless otherwise noted), and the co-polymer has a glass transition temperature which is below 1001 C. Compositions according to one preferred form of the invention comprise an amine salt of styrene-methacrylic acid co-polymer in which the co-polymer has a styrene content between about 10 and 90 percent by weight based on the total weight of the polymer. According to one preferred form of the invention, the total amount of applied creping adhesive is from about 40 grams/ton to about 5 kilograms/ton of dry weight creping adhesive, based on the dry weight of the paper web.
[0030] The invention also includes a process for creping tissue paper, which process comprises: a) applying an adhesive which comprises an aqueous dispersion comprising from about 75% to about 99.9% water and from about 25% to about 0.1% solids to a dryer, wherein said solids comprise an amine salt of styrene-methacrylic acid co-polymer;
[0031] b) pressing a tissue paper web against the dryer to adhere the web to the surface of the dryer; and c) removing the web from the dryer via a doctor blade.
Amine Salt of Styrene/Methacrylic Acid Co-Polymer
[0032] The preparation of styrene/methacrylic acid co-polymers is known in the art. One method for their preparation involves charging a 3-necked 1 L flask equipped with a mechanical stirrer and heating mantle with 209.46 g of isopropanol and 200.86 g of water, and heating under mild agitation with a slow nitrogen purge of the headspace, until a gentle reflux is achieved, which occurs at about 80° C. A first stream comprising 24.74 g of a 14.3% aqueous sodium persulfate solution is slowly added to the content of the refluxing contents of the flask, simultaneously with a second stream comprising a liquid mixture of 70.68 g of styrene and 70.68 g of methacrylic acid, over the course of about 2 hours. Following the addition, the temperature is maintained at reflux for an additional 2 hours to ensure completeness of reaction. Then, an additional 15.4 g of 14.3% sodium persulfate is added, and the temperature maintained at reflux for one additional hour to digest residual quantities of the monomers.
[0033] To prepare an amine salt of a co-polymer produced as above, namely the triethanol amine salt (TEA), the flask from the above containing the crude reaction product mixture is set up for distillation by affixing a condenser and head thereto. The flask is heated until the azeotrope of isopropanol and water begins to distill, at which time 123.57 g of TEA is slowly added to the flask during the distillation at a rate which is approximately equal to the rate at which the azeotrope is being distilled. The reaction is completed when the temperature reaches 100° C., after which point the flask is cooled to 50° C. and 100 g of water is added, which lowers the viscosity of the mixture.
[0034] In the above-described method for preparing a styrene-methacrylic acid co-polymer, the styrene/methacrylic acid ratio is about 50:50. Other ratios of styrene/methacrylic acid in the range of 10:90 to 90:10 by weight are suitable for providing co-polymers useful in the present invention and are readily achievable by those of ordinary skill in the art by altering the ratio of monomers.
[0035] The weight average molecular weight of a styrene/methacrylic acid co-polymer useful in accordance with the present invention is in the range of about 1,000 to about 500,000, with molecular weights having any value in the range of 2,000 to 400,000 being preferred, and with molecular weights having any value in the range of about 3,000 to about 300,000 being most preferred. The molecular weight is controlled by the concentration of the initiator, and the chain transfer agent, as is known in the art. While in the present invention it is most preferred during the preparation of our polymer(s) that the chain transfer agent is isopropanol and the initiator is persulfate ion, we realize that other chain transfer agents and initiators are known to those skilled in the art are useful in preparing such polymers as those described herein; hence this should in no way be construed as delimitive of the present invention.
Adhesion Test
[0036] Materials useful as adhesives in creping paper need to function as adhesives, to a balanced degree. A suitable test for evaluating the adhesiveness of such agents involves heating a plate of 2×4 inch stainless steel on a hot plate to about 120° C., and then applying a 76 micron adhesive coating to the test plate using a suitable wire rod. A piece of filter paper is then quickly and carefully applied to the film and rolled 10 times with a paint roller to achieve uniform contact between the paper, adhesive and metal surface. Subsequent heating of the plate to 120° C. for 2 min, the metal coupon with the attached paper test strip is then removed and cooled to room temperature, after which the paper is peeled at an angle of 90° using an INSTRON® peel strength tester. Duplicate runs were made for each product, and the average values were calculated. A plot showing the average adhesion (lb/in) for various products is set forth below.
[0037] Interestingly, when compared to the sodium salt of styrene-methacrylic acid co-polymers (“STYMA”), the amine salt(s) of STYMA (and especially that of TEA) is much more efficacious, as reflected by much higher adhesion values for the latter. STYMA with amine salt also appeared to be more effective than the polyamide-epihalohydrin resins such as KYMEN® 557 H and SOLVOX® 681-A of the prior art (see for example U.S. Pat. Nos. 5,388,807, 5,786,429, 5,902,862, and Canada Patent No. 979,579). HARTOMER® AFX is a blend of STYMA sodium salt, sorbitol and polyvinyl alcohol.
[0038] The glass transition temperature of the polymer also plays an important role in obtaining good creping properties. The glass transition temperature for an amorphous polymer is the temperature at which the material undergoes a phase change from being a glassy or brittle state to a plastic or rubbery state. To obtain adequate adhesion, the polymer's glass transition temperature has to be below the operating temperature, which in the case of paper creping processes is about 100° C. Above the glass transition temperature, sufficient contact between the adhesive and the dryer surface is achieved, while below the glass transition temperature, the polymer is too brittle and hard to function well. The glass transition temperatures of various crepe aids are listed in Table 1:
TABLE 1 Glass Transition Temperatures of Various Crepe Aids Product T g (° C.) STYMA (50:50) + TEA 24 STYMA (50:50) + NaOH >150 HARTOMER ® AFX >150 SOLVOX ® 681-A 88 Polyvinyl alcohol (AIRVOL ® 540) 68 KYMENE ® 557 H 58
[0039] As can be seen, STYMA+TEA has the glass transition temperature much lower than STYMA+NaOH. This may be one of the reasons for the excellent performance of the former.
[0040] Consideration must be given to the fact that although this invention has been described and disclosed in relation to certain preferred embodiments, obvious equivalent modifications and alterations thereof will become apparent to one of ordinary skill in this art upon reading and understanding this specification and the claims appended hereto. Accordingly, the presently disclosed invention is intended to cover all such modifications and alterations, and is limited only by the scope of the claims which follow. | The present invention provides compositions a useful in the creping of paper products such as facial tissue and bathroom tissue. The compositions comprise an alkanolamine salt of a styrene-methacrylic acid co-polymer. According to a process according to the invention, a composition of the invention is contacted with the dryer cylinder in a creping process. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims benefit of priority to U.S. Provisional Patent Application No. 61/759,845 entitled ALUMINUM PRINTED CIRCUIT BOARD FOR LIGHTING AND DISPLAY BACKPLANES and filed on Feb. 1, 2013, which is hereby incorporated by reference in its entirety.
BACKGROUND
[0002] Lighting and display applications that use LEDs or other forms of solid state lighting are not 100% efficient (electrical to optical efficiency) and thus generate heat. At the present time, even 50% efficiency is a difficult target, implying the generation of a lot of heat. Most solid state lighting devices will be more efficient and function longer if kept cooler. An ordinary epoxy glass board will have a thermal conductivity (TC) of less than 1 W/m-K (Watts per meter per degree Kelvin or Centigrade). The higher that thermal conductivity, the lower the temperature differential needs to be to dissipate a given amount of power. Applicants have found that a metal-based PCB improves this heat dissipation to achieve greater efficiency and may improve service life.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is a cross-sectional view of a metal PCB in accordance with some embodiments.
[0004] FIG. 2 is a cross-sectional view of an LED lighting display in accordance with some embodiments.
DETAILED DESCRIPTION
[0005] As ordinary epoxy glass, PCB has a thermal conductivity (TC) of about 1 W/m-K (the units will be understood in what follows). Aluminum has a TC of more than 200 and alumina (aluminum oxide ceramic created by oxidizing aluminum metal) has a TC greater than 24. A PCB is typically 62 mils thick (one mil=0.001 inches or 25.4 um), making the minimum distance the heat has to travel about 1545 um (62 mils×25.4 um/mil). The power dissipation for a given configuration is P=A·Tc·ΔT/Z (where A is the area of the material conducting the heat, Tc is the TC, ΔT is the temperature differential, and Z is the thickness of the conducting material). Assuming that the areas of the conducting surfaces are the same, an aluminum PCB arrangement has two favorable aspects. The thickness of the dielectric layer is less than about 50 um, making the power dissipation capability more than 30 times that of the PCB. The TC of this layer is more than 20 times greater than an epoxy glass based PCB. So at a minimum this technology can increase the power dissipation or correspondingly (see the equation above) decrease the temperature differential required for a given power dissipation by at least about 600 fold.
[0006] FIG. 1 illustrates the concept of a metal PCB 100 . The base 110 of the PCB 100 is metal of thickness sufficient to conduct the heat away at a specified temperature differential (ΔT). Generally, the metal layer is the thickest of all layers. This layer acts as a heat sink. The base 110 is patterned (by lithography, screen printing, etc.) and covered by a dielectric 120 , the dielectric is patterned and metalized 130 . This process can be repeated for a number of layers. While in principle this process could be repeated indefinitely, in some embodiments the PCB has 3 to 10 layers, in some embodiments 6 to 8 layers, in some embodiments 3 to 7 layers, and in some embodiments 3 to 6 layers. In some embodiments, the PCB has three layers, four layers, five layers, six layers, seven layers, or eight layers, or any value or range of values between any of these values.
[0007] Some embodiments include a method comprising:
screen printing on a mask; anodizing the aluminum with a rather thick layer (70 um to 80 um) of anodization to form a dielectric layer; patterning the anodized layer exposing the areas where traces and pads will later be located; zincating in preparation for electroless nickel (EN) deposition. The zincation step requires that the nitric acid etch is either eliminated or made less aggressive so that it does not remove significant amounts of the anodized dielectric layer. The zincate treatment itself removes some anodization (about 40 um), which was the motivation for the excessively thick initial anodized layer; and EN plate deposition to desired thickness.
[0013] There are many variations on this theme. For example, the EN layer can be made continuous so that later a new mask can be used to expose only the areas to be plated up and later after stripping the mask etch off the unwanted connecting field metal. Another possibility is to skip the whole EN step altogether and use a photo-catalytic decomposition process to produce a strike layer. For example, the anodized plate could be placed in a copper formate bath and laser write the desired pattern.
[0014] The metal substrate may be any suitable metal. Aluminum and titanium both anodize well, and are particularly well suited for this use. Nevertheless, other metals may be used by producing a dielectric layer by techniques other than anodizing. In the case of many metals including aluminum, a batch nitriding process can produce a dielectric layer that can then be further processed. The improved dissipation of those metal PCBs are well-suited for LED light displays.
[0015] Up to ⅓ of the light from an LED die is emitted from the sides. This light is frequently poorly captured by standard LED packages. The metal PCB structure described herein can be modified to capture and emit much of this lost light emission.
[0016] As seen in FIG. 2 , metal PCB substrate 110 (heatsink) is being used as common anode or cathode. In this arrangement, the LEDs, or groups of LEDs, can be run in parallel.
[0017] The LED die 200 may also be chip on carrier or any other form of packaging that does not significantly obstruct extraction of the side emitted light (meaning light that is emitted from the edges of the LED chip). As shown in FIG. 2 , the metal layer 110 of the PCB defines a well which dips below the surface of the metal layer. An LED chip is secured at the bottom o fthe well and operatively coupled to the metalized layer 130 and the metal layer 110 . The well generally has sloped or curved sidewalls 112 to extract LED edge light and reflect it away from the PCB, thus increasing light output. In some embodiments, the light extracted from the LED edge is then reflected toward an optional QD quantum dot conversion film 300 by the sloped walls. The walls are shown as straight, but they could be curved in a way to make the reflected light highly directional. In some embodiments, the well could have a parabolic or other shape designed to reflect and/or focus the light. Importantly, because the LED chip is in direct contact with the metal layer, heat is quickly conducted away from the LED, leading to cooler operating conditions.
[0018] The light coming out the side of the LED is efficiently extracted into a nano-particle filled polymer matrix 250 (e.g., titanium oxide nano-particles in silicone, where the concentration is adjusted to give the best refractive index for light extraction from the LED), reflected upward by the sides of the well the LED resides in, and is indexed matched to air by the polymer matrix 250 that protects the wire bonds 260 . This may achieve up to 20% to 25% more useful light out of the LED. Some of the side emitted light will be useful even if nothing is done to extract or redirect it. This arrangement is useful for LED die and chip on carrier packages where the packages do not block the sides of the LED in ways that make efficient light extraction difficult or impossible. The LED may also be provided with a protective polymeric lens 270 .
[0019] The QD conversion film comprises a plurality of quantum dots which may further improve the performance or alter the qualities of the light produced by the LED.
[0020] Although this description focuses on aluminum as the substrate, many other metals and alloys can be used at each step (list them). Aluminum is well-suited because it has many desirable characteristics such as weight, TC, anodizability, etc. Solution processing, while inexpensive and relatively easy, is a preferred technique, but is by no means the only technique available for laying down dielectric and traces. In a volume production environment, vacuum deposition techniques may be used and in some instances can be low cost.
[0021] Some advantages of some embodiments is that they solve thermal management and light extraction with a simple low cost, highly manufacturable solution.
[0022] Currently, high thermal conductivity PCBs are metal core boards which are quite expensive and not nearly as effective as a true metallic PCB. The reason that this technology has not been developed previously is that the development thrust in PCB technology has been toward smaller and faster. This technique described herein is not likely to give as fine a feature as the better PCB processes can achieve. These boards may be slow because of the large distributed capacitance due the high dielectric constant of alumina (about 25) and the mere 40 um or so of dielectric thickness. However, with the advent of LED lighting there is an opportunity for this technology to move into the spotlight in a high volume way.
[0023] At the heart of it, the basic aluminum PCB invention is replacing what would normally be done by expensive physical vapor deposition PVD, chemical vapor deposition CVD, etc. processes, with much less expensive solution processing.
[0024] The major differences between this approach to thermal management and the currently popular metal core PCBs is:
[0025] A tradeoff of high speed (low K dielectrics, etc.), fine pitch (close spacing of fine traces—1 mil traces on a 2 mil spacing) has been made for superior thermal performance.
[0026] The cost has been minimized by choosing inexpensive high volume techniques. The techniques are based on batch solution processing and additive processes. [Recall that PCBs are generally based on subtractive technology, meaning that copper is removed instead of added.]
[0027] Although in principle, these techniques can be used to build multilayer boards, most likely two layer boards will dominate for lighting applications and 4 to 8 layer boards for display applications.
[0028] There are no organic compounds in the final product meaning that subsequent processing will be more thermally tolerant than epoxy-glass PCBs.
[0029] What these metal PCBs may lack when compared to their contemporaries is made up by improved light extraction in solid state lighting. Efficient light extraction is critically important to making efficient LED lighting. With every bit of added efficiency either the efficiency of the LED goes up because they can be run at a lower current (LED efficiency degrades significantly as the current is increased) or the cost of the light goes down because less LEDs are required for a given light output. Either way, coupling a metal PCB to an LED or LED array achieves significant gains in LED efficiency.
[0030] The concept originated from using batch nitriding to produce the dielectric layer. Then the idea of the metal PCB was discussed. After considerable investigation we started investigating anodizing as a better alternative to nitriding. Incidentally, the motivation for considering nitriding before anodizing was largely driven by the fact that aluminum nitride has a TC around 200, so is nearly as good a thermal conductor as aluminum itself, while aluminum oxide (alumina) has a TC around 25. So there is an 8× penalty for going to anodizing. The fact is that dielectric films are so thin that it does not make enough difference in the LED operating temperature to have significant effect on the efficiency. | Disclosed herein are metal printed circuit boards, particularly aluminum based printed circuit boards. Also disclosed are methods of making the metal printed circuit boards. Also disclosed are lighting systems, such as LED lighting systems, employing the disclosed metal printed circuit boards. | 5 |
BACKGROUND OF THE INVENTION
The invention relates to improvements in suspended ceiling componentry and, in particular, to an improved wall molding for suspended ceiling systems.
PRIOR ART
Typically, a suspended ceiling includes a wall molding at the intersection of the wall and plane of the ceiling. The wall molding serves to support the edges of ceiling tiles and serves to conceal these edges to provide a finished appearance. The wall molding, typically, can also support the ends of tees comprising the grid carrying the ceiling tiles. Conventional wall moldings are manufactured as elongated angles, typically being roll-formed from strips of prefinished sheet metal. Premium or commercial grade wall angles can have a reinforcing hem along the free edges of their legs. The wall molding or angle ordinarily is installed at the desired height on a wall by suitable fasteners such as screws, nails, staples or the like. The height may be determined by a chalk line, laser level or other method. In any case, a problem encountered by the installer with conventional wall molding is the difficulty in holding it level and abutted against a previously installed piece and fastening it to the wall all at the same time. The task is also difficult because the manufactured length of the wall molding is considerable in comparison to its transverse dimensions, so that it is not perfectly rigid.
Additionally, because of the length of a standard wall molding, it is difficult to register the end of a new piece with the end of the previously installed piece while holding the new piece at or near its mid-length. These difficulties add to the time required to install the wall molding, particularly when care is taken to mount the molding in a straight line at an exact height and in registry with a previously installed length of molding.
SUMMARY OF THE INVENTION
The invention provides a wall molding with an extension or formation that enables it to self-align with a previously installed piece. The self-aligning feature permits the wall molding to be installed with less time and greater accuracy in positioning when compared to prior art products. With the self-aligning feature of the invention, the wall molding can be easily registered endwise and laterally with a previously installed piece. The self-aligning feature of the invention is capable of vertically supporting and laterally holding the associated end of the wall molding. As a result, the installer is relieved of a need to concentrate on positioning and aligning this end of the molding and can advantageously direct his/her attention to supporting and fastening a mid-length portion of the molding to initially fasten the molding to the wall.
In a preferred embodiment of the invention, the self-aligning feature has the form of a right angle extension or tongue created by parts extending from each leg of the wall molding proper, i.e. the main body of the wall molding. The tongue elements or parts are stepped out of but parallel to the planes of their respective legs a distance substantially equal to the thickness of the legs. This step or offset of the alignment or tongue elements allows them to hold the legs of adjacent ends of a pair of moldings in alignment. With the legs held in alignment by the disclosed tongue parts, only a very moderate longitudinal force on the molding is needed to establish and maintain a good end-to-end fit between wall molding pieces that has the appearance of a butt joint.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a somewhat schematic perspective drawing of a workman installing a wall molding constructed in accordance with the present invention;
FIG. 2 is a fragmentary perspective overhead view of a suspended ceiling system employing the wall molding of the invention;
FIG. 3 is an enlarged fragmentary view of a joint between the ends of a pair of wall moldings showing the alignment feature of the invention;
FIG. 4 is a fragmentary plan view of the end of a wall molding including the self-aligning feature of the invention; and
FIG. 5 is an end view of the self-aligning feature of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and in particular to FIG. 2 , a conventional suspended ceiling system 10 includes a rectangular grid 11 of inverted metal tees 12 on which is carried rectangular or square lay-in panels or tiles 13 . The tees 12 are typically suspended with wires 14 from an overhead superstructure. The edges of the ceiling system, where the ceiling meets the walls, designated 16 , of a building, are finished or trimmed with a wall molding 17 .
The wall molding 17 is in the form of a right angle having perpendicular generally planar legs 18 which, in the illustrated embodiment, are of equal width. As is conventional, the wall molding can be manufactured by roll-forming sheet metal, typically steel, which is pre-painted. The legs 18 , at their longitudinal free edges 19 , have a roll-formed hem 21 where the sheet metal stock is bent back over itself to stiffen the edge and provide a finished appearance. The hem 21 of folded over material normally has a width substantially less than the width of its associated leg 18 , so as to leave a gap 22 between an inner edge 23 and the opposite leg 18 . At one end of the wall molding 17 , a longitudinally extending tongue 24 is provided, in accordance with the invention, to afford a self-alignment feature. The opposite end of the wall molding 17 is plain without a tongue and simply sheared across a plane transverse to the longitudinal direction of the wall molding. The tongue 24 in the preferred embodiment is formed integrally as one piece with the main body of the wall molding 17 , i.e. the wall molding proper. The tongue 24 has integral, mutually perpendicular planar parts 26 protecting longitudinally from a respective one of the legs 18 of the wall molding proper. Each tongue part 26 is stepped out of and is parallel to the plane of its respective leg 18 preferably by a distance generally equal to the thickness of the stock forming the wall molding 17 . Relatively small web or bridge elements 27 lying in a common plane transverse to the longitudinal direction of the wall molding 17 form the transition between the legs 18 and the tongue parts 26 . The tongue parts 26 are integrally joined as one piece at a corner 28 . Ideally, the length of the tongue 24 , i.e. the distance it projects longitudinally from the wall molding proper, is less than the width of the legs 18 . The width of each tongue part 26 is, preferably, slightly less than the gap 22 between its adjacent hem 21 and the opposed leg 18 . Corners 29 of the free ends of the tongue parts 26 are beveled or clipped.
By way of example, but not limitation, the wall molding has a nominal length of 10 or 12 feet; the legs 18 are ⅞″ wide; and, the thickness of the sheet stock forming the wall molding is between about 0.015″ to about 0.030″.
In a typical installation, the wall molding 17 is attached to a vertical wall 16 at a height and orientation where one of its legs 18 lies at the plane of the ceiling system surface visible from below and the other leg 18 extends upwardly in abutting contact with the wall 16 . Typically, the wall molding 17 is attached with screws, nails or other fastening means ordinarily at regularly spaced locations. The elevation of the wall molding 17 can be set by a laser, chalk line or other known technique. Because the usual length of a piece of wall molding 17 is great as compared to the transverse dimensions of the legs 18 , the wall molding is somewhat flexible and, therefore, difficult to maintain relatively straight where it is temporarily supported at only one or two points along its mid-length. This characteristic has made it difficult with prior art wall molding products to quickly and accurately manually position a length of wall molding in proper registration with the end of a previously installed piece of wall molding and in line with the desired location and, at the same time, fix the wall molding in place with a fastener.
After the first piece of wall molding 17 has been installed, subsequent pieces are conveniently and quickly installed with the benefit of the invention. The invention facilitates installation of a wall molding 17 such as in a manner represented in FIG. 1 . An installer 31 , holding the wall molding 17 near its mid-length can lay the end portion associated with the tongue 24 on the plain end of the previously installed piece of wall molding 17 . The installer 31 can then level the new piece out to the desired elevation and, if more than the tongue 24 is overlapping the plain end of the previously installed piece, simultaneously or subsequently pull the piece away from the preceding piece until only the tongue is in overlapping contact with the previous piece. Thereafter, the piece 17 being installed can be lightly forced against the preceding piece to achieve the appearance of a tight butt joint at a transverse faux end plane where the tongue 26 extends from the legs 18 . At this time, the wall molding piece being installed can be readily fixed in place with a fastener near its mid-length while the installer need only support the wall molding with one hand since the previously installed wall molding 17 is supporting and locating the new piece through the medium of the tongue 24 .
The geometry of the tongue 24 has certain benefits. The offset of the tongue parts 26 from the planes of respective legs 18 assures that the legs 18 of a pair of joined wall molding pieces are in planar alignment. The tongue parts 26 fit in the space or gap 22 between the hem edge 23 and the opposed leg 18 of the joined wall molding piece thereby producing a laterally locked condition of the tongue in the planes of both legs 18 . The tongue 24 , being shorter than the width of the legs 18 , enables it to remain without modification or removal when a corner joint between perpendicular walls 16 is established between two wall angles. The beveled or otherwise trimmed corners allow the tongue 24 to slide longitudinally in the gaps 22 between the hems 21 and opposed legs 18 without jamming. The limited width of the tongue parts allows the end edge areas 32 of the legs 18 laterally outward of the bridge elements 27 including the ends of the hems 21 to abut the plain end of the mating previously installed piece 17 so that any tendency for the bridge elements 27 of the new piece to ride up over the previously installed piece under a longitudinal compressive force is suppressed. This abutting action is assured because the height of the hems 21 from the plane of their respective legs is greater than the thickness of the leg stock so that the hem end edges of the plain end snag the opposing end edges 32 .
The following more fully explains the role of the hems 21 in establishing a positive end-to-end relationship between a pair of wall moldings. The depiction of the area of the hems 21 in the view of FIG. 5 is somewhat schematic. Generally, it is the practice in the industry that the inside of the bend at the longitudinal edge of each leg that forms the hem has a measurable radius such that a space exists between the hem and the leg proper, at least at and near the bend. The end edges are typically created by a shear blade that moves in a direction transverse to the longitudinal direction of the wall molding and along a line that bisects the 90° angle between the legs 18 . The shear blade can operate from the space included between the 90° spacing between the planes of the legs or from the other side of the wall molding, i.e. the space of the 270° angle between the legs. Depending on the space from which the shear operates, the hems 21 may tend to be permanently deformed towards the leg proper or away from the leg proper. In the former case, the effective thickness of the legs, including the partially flattened hem will normally be more than twice the thickness of the sheet stock. As described above, the bridge elements 27 are proportioned to space the tongue parts 26 a distance equal to the thickness of the material stock from the planes of the legs proper. Additionally, the bridge elements 27 are formed so that they exist mostly and, preferably, exclusively longitudinally rearwardly of the plane of the end edges 32 of the legs and hems. The functional result of the described end edge structure and the bridge element structure is that a longitudinal compressive force between a wall molding piece being installed and the previously installed piece does not produce a camming action by the bridge elements 27 which could otherwise allow the wall molding piece being installed to slip onto and over the previously installed piece. This potential camming action is prevented by abutting contact between the end edges of the wall molding associated with the tongue and the opposing edges of the plain end of an identical wall molding. Even if the tongue 24 and plain ends are misaligned by a distance equal to the thickness of the sheet stock, as might occur if the bridge elements 27 operate as camming elements, the effective thickness at the hems, being more than double the stock thickness, assures that at least portions of the end edges abut so as to prevent over-riding of the tongue end past the plain end. Also, if the tongue and plain ends of a pair of wall moldings being joined are angularly misaligned about their longitudinal axis, one of the end edges 32 will typically catch on the edge of the opposing plain end with the associated tongue part resting in the space or pocket formed by the hem of the plain end.
Other known wall moldings with cross-sections different than the illustrated right angle, equal leg width molding can be provided with the self-alignment feature of the invention. For example, the legs can have unequal widths, e.g. 1″ by 1½″ and/or the cross-sections can be modified J or C-shapes, or can be stepped. In some instances, a leg can have a width as much as about 1½% of the length of the molding. Where desired, a wall molding incorporating the invention can be formed of other suitable materials and processes besides roll-formed sheet steel, such as roll-formed sheet aluminum, aluminum extrusion, or plastic extrusion of polycarbonate or the like.
It should be evident that this disclosure is by way of example and that various other changes may be made by adding, modifying or eliminating details without departing from the fair scope of the teaching contained in this disclosure. The invention is therefore not limited to particular details of this disclosure except to the extent that the following claims are necessarily so limited. | A wall molding for suspended ceiling systems has a self-aligning feature adapted to locate one end of a piece being installed on the end of a previously installed piece so that an installation of high quality workmanship is quickly obtained. The self-aligning feature is in the form of a tongue extending longitudinally beyond a faux end and adapted to nest in the previously installed piece. The tongue fits within the spaces between hems on the longitudinal edges of legs of a right angle cross-section and the opposed legs so that the tongue is laterally restrained in the planes of the legs and is longitudinally restrained by abutting end edges. | 8 |
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a connector assembly for coupling one connector to a mating component, and relates more particularly to an improvement in a latch/release mechanism for releasably coupling the connector to the mating component without the hitherto known need to do so using tools.
Connector devices which are known are disclosed as follows:
Davis et al. U.S. Pat. No. 5,088,935, issued on Feb. 18, 1992 discloses a latch actuator for a connector which employs a sliding actuator which coacts with pivoting latches. The clasps engage the standoffs at outside portions opposite the location of the connector.
Haag et al. U.S. Pat. No. 5,123,858, issued on Jun. 23, 1992 discloses a lockable electrical connector having struts mounted to a slide which engage with retaining grooves. Portions of the slide reside outside of the pins.
Hashiguchi U.S. Pat. No. 5,197,901, issued on Mar. 30, 1992 and Hirai U.S. Pat. No. 5,340,329 Aug. 23, 1994 disclose a lock-spring and lock-equipped connector which use operating sections located externally of an associated pivoting lock spring disposed inwardly thereof. The locks engage the posts at outside portions that are opposite the location of the connector.
Clark et al. U.S. Pat. No. 5,522,731, issued on Jun. 4, 1984 discloses a shielded cable connector which uses a pair of side walls having a plurality of spring contacts. The side walls require intervention (such as a tool) to disengage from the mating connector.
Stinson et al. U.S. Pat. No. 5,741,150, issued on Apr. 21, 1998 discloses a unitary spring latch for an electrical connector assembly which employs a pivoted latch mechanism which latch involves numerous bends and punches to effect functionality. The latch engages the post at an outside location relative to the connector.
Jones U.S. Pat. No. 5,775,931, issued on Jul. 7, 1998 discloses externally located latch members which are fixed midlength to the connector to effect a pivotal connection. The latch member engages an over portion of the post.
Chang U.S. Pat. No. 5,860,826, issued on Jan. 19, 1999 discloses an electrical connector fastener configured to cooperate with fasteners having an enlarged head. The remaining plate engages the fastener on an outer portion.
Burtt et al. U.S. Pat. No. 2,760,174, issued on discloses a locking mechanism for connectors, but does not employ side compartments to house the latch mechanism, nor are there any post type connectors used. A portion of the locking mechanism extends outwardly past the projection of the locking lug.
As can be seen from these devices, there is a need for quick connect latch and release mechanisms for cable terminators which cooperate with corresponding structure on the header or corresponding part to lock the terminator in place. A need also exists to provide a latch assembly, that is compact. In addition, the process of connecting the cable terminator to the header requires the user be assured that a positive connection has been achieved. The importance of having such an assurance is that the user is able to know that positive contact between all the contacts of the header and those of the cable terminator or between two coacting terminators is achieved thereby assuring a complete electrical connection between the two parts.
Accordingly, it is an object of the invention to provide a device associated with the connection between, for example, a cable terminator and a header, or between two complementary formed cable terminators which are connected together such that the connection is capable of rapid latch and release without the need of tools for plugging or unplugging the connection.
It is still a further object of the invention to provide an electrical connector of the aforementioned type which provides an audible click during the interconnect process thereby signaling to the user that a positive lock condition of the connector with its corresponding part has been attained.
A further object of the invention is to provide a latch element usable in the aforesaid connector which is manufactured from a material that exhibits a high elastic limit in memory such that, depending on the particular design requirements, the material can be punched and formed into a spring latch capable of effecting the aforesaid ends.
Still a further object of the invention is to provide a quick latch spring release mechanism for a cable assembly which effects smooth engagement between the latch and a profiled locking head allowing the spring latch to smoothly engage the profiled head and lock into position with it.
Yet still a further object of the invention is to provide a quick latch spring release mechanism for a cable assembly of the aforementioned type which employs a spring latch mechanism which is enclosed within a housing of a terminator body.
Another object of the invention is to provide a latch element usable in the aforesaid connector which is compact.
Other objects and advantages of the invention will become apparent from the following description and in the appended claims.
SUMMARY OF THE INVENTION
The invention resides in a quick latch/release mechanism in a connector, which could be used in a cable assembly, which provides both rapid latch and release of the cable terminator from the mating component, such as a header to which it is fastened, without requiring tools for plugging/unplugging the cable assembly. The connector includes a body portion; a conductive element secured to said body portion for engaging a corresponding conductive element on the complementary connector; and at least one elongated latch element having one end fixed to said body portion and having another opposite free end disposed for deflection by the guide post of the corresponding connector during mating, said opposite free end of said elongated latch element having a recess formed thereat for engaging with and releasably connecting to the guide post of the corresponding connector received to effect positive locking.
Ideally, the latch element is a generally elongated metal leaf spring and a recess is formed in the free end of the latch element as a bell-shaped cutout having a base defining the bottom of the bell-shaped cutout, the base of the cutout being orientated generally perpendicularly to the longitudinal extent of the latch element.
Preferably, the body of the cable terminating assembly has bow cut portions extending inwardly transversely of the central axis thereof and coinciding with the location of a length of the latch element juxtaposed thereto and the latch element one end being secured to the body portion such that it is normally outwardly biased in a direction transversely outwardly of the central axis.
In the preferred embodiment, the latch element has a bow shape intermediate of its length which coincides positionally with the location of a respective one of the bow cut portions so as to cooperate with the body portion to allow release of the latch element from a guide post when the latch element is squeezed against the body portion.
Ideally, the at least one sidewall compartment is provided as part of the body portion and has a journaling surface having a longitudinal extent extending in a direction parallel to the central axis and being disposed between the top and end openings. The journaling surface is correspondingly sized and shaped to receive and bear against the outer surface of a guide post. The connector preferably has two sidewall compartments each respectively disposed generally coincidentally with one of the first and second side ends and each is adapted to receive a guide post therein in a direction parallel to the central axis of the assembly.
Desirably, the top opening in the top surface of the at least one sidewall compartment defines a straight edge against which the latch element is normally biased when the connector is in an unconnected condition.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially fragmentary front elevation view showing a cable terminator connected to the transverse side of a support surface using the latch device of the present invention.
FIG. 2 is a partially fragmentary side elevation view of the cable termination assembly connector shown in FIG. 1 .
FIG. 3 is a vertical sectional view taking along line 3 — 3 of FIG. 1 .
FIGS. 4A and 4B show respectively a side and a top plan view of the spring latch of the invention.
FIG. 5 is a partially fragmentary view showing the guide post in detail of the lead used in the connection of the present invention.
FIG. 6 is a partially fragmentary view taken on lines 6 — 6 of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, the invention is embodied in a connection referenced generally as 2 between electrical connectors. One half of the connection 2 can be comprised of a receptacle connector 4 which extends outwardly from a support surface 6 which, for example, may take the form of the back housing of a personal computer or the like. The other half of the connection 2 can be a cable terminating assembly 12 .
Since the present invention could be used with any type of connector, only a brief description of the connector shown in the figures follows. The receptacle connector 4 has an internal socket 8 in which are disposed a plurality of terminals or contacts, as is known in the art. The socket 8 is further adapted to receive a corresponding male portion 10 of a cable terminating assembly 12 such as a card edge. The male portion 10 extends outwardly in a direction parallel to the direction of the central axis CA of the assembly 12 and is preferably disposed transversely along the front face of a cable terminating assembly 12 .
The receptacle connector 4 which is mounted to the support surface 6 has a width W which is defined in part by a first end 14 and a second end 16 of the socket 8 . Disposed coincidentally with and proximate each of the longitudinal ends 14 and 16 of the receptacle connector is a fixedly mounted guide post 20 , 20 which extends outwardly from and generally perpendicularly to the support surface 6 a given distance L 2 and each define the outer limits of the width dimension W.
The cable terminating assembly 12 has body portion 7 of a width W 1 which is at least equal in dimension to the width W of the receptacle connector 4 . The body can house a PCB to which wires (not shown) from one or more cables secure. The other end of the PCB can have conductive pads along an edge to mate with receptacle 4 . The receptacle connector width W is further prescribed by two distal end compartments 22 , 22 which provide the means 24 for aligning, locking and unlocking the cable terminating assembly 12 to/from the receptacle connector 4 in a new and unobvious way as will become more readily apparent. The body portion 7 could be formed from, for example, two mateable half shells.
The means 24 disposed in the terminating assembly 12 includes a cantilevered spring latch 28 which is normally directed substantially parallel to the central axis CA of the body 7 of the assembly 12 and has one end 13 which is fixedly attached to and within the body 7 of the cable terminating assembly and has an opposite free end 15 which is movable inwardly toward the central axis CA of the cable terminating assembly 12 when squeezed by a user or when initially engaging guide post 20 .
Each of the distal end compartments 22 , 22 , as illustrated in the top partially fragmentary view in FIG. 6, has a generally rectangular top opening 30 formed on the top surface 32 thereof. The portion of the spring latch 28 associated with the free end 15 is received within an associated one of the distal end compartments 22 , 22 such that the outwardly disposed side face 21 of the latch 28 is engaged by the side surface 23 of the top openings 30 , 30 so as to positionally maintain the spring latch 28 against further outward movement when the cable terminating assembly is not connected with the receptacle connector 4 . Also, in the unconnected condition of the connector, these side surfaces of the top openings 30 , 30 also respectively locate the corresponding free ends 15 , 15 of the spring latches 28 , 28 in an aligned condition with corresponding portions on the guide posts 20 , 20 so that upon continued axial movement of the assembly 12 along the axis CA on the guide post 20 , 20 , the assembly 12 automatically locks with the guide posts 20 , 20 in accordance with a further aspect of the invention.
The end face 27 facing the support surface 6 of each of the distal end compartments 22 , 22 has an end opening 36 , 36 which is respectively aligned with one of top openings 30 , 30 in the assembly 12 and each is spaced apart from one another by a given distance so as to be in spatial correspondence with the guide posts 20 , 20 . Each end opening 36 , 36 is also correspondingly sized and shaped to receive an associated one of the guide posts 20 , 20 therewithin. Each distal end compartment 22 , 22 further has an internal cylindrical journaling surface 40 , 40 which is located in axial alignment with the top and end openings 30 and 36 in each side compartment 22 , 22 , and each is correspondingly sized and shaped to act in close tolerance with the outer surface of a respective one of the guide posts 20 , 20 received therein to provide a bearing surface thereagainst to further add stability and strength to the connection.
Referring now to FIGS. 4A and 4B, and in particular to the detailed construction of the spring latch 28 , it should be seen that each of the spring latch elements 28 , 28 is formed from a suitable resilient material such as a strip of high memory metal leaf spring whose fixed end 13 is secured against movement within the body 7 of the cable terminating apparatus 12 through the intermediary of locking notches 42 , 42 formed therein.
Proximate the free ends 15 , 15 of the spring latches 28 , 28 is a generally bell-shaped recess or cutout 50 , 50 formed therein. Each of the cutouts 50 , 50 has a flat base portion 52 connected to an arch-shaped upper portion 53 adapted to cooperate in a receiving, releasable locking engagement with a correspondingly shaped conical lead portion 54 (see FIG. 5) formed at the distal end of each of the guide posts 20 , 20 .
The lead portions 54 , 54 of the guide posts 20 , 20 each has an undercut portion 56 , 56 which provides an annular recess or release area 55 in which the a portion of the spring latch between the tip of the free end 15 and the flat base portion 52 of the cutout 50 , 50 locks into under outward bias upon the continued movement of the assembly 12 towards the receptacle connector 4 in the indicated arrow direction along the axis CA. In other words, length L 1 represents the effective length of the spring latch 28 from its fixed end to the flat base portion 52 of the bell-shaped opening 50 at the free end 15 thereof. Similarly, dimension L 2 represents the effective length of guide posts from the header or support surface 6 to the shouldered annular recess 55 on the guide posts. The dimensions L 1 and L 2 are selected relative to one another, and to the effective dimensions of the corresponding fitting parts of the male portion 10 of the cable terminator assembly 12 and the corresponding receptacle connector socket 8 such that as the cable terminator assembly 12 is moved axially along axis CA along the guide posts 20 , 20 , the male portion 10 of the assembly 12 and the socket 8 of the receptacle connector 4 mate to one another while at the same time the free ends 15 , 15 of each latch 28 are ramped over the conical surfaces of the lead portions 54 , 54 of the posts 20 , 20 and upon the end of such relative axial movement between the male part 10 and the socket 8 , the spring latch elements 28 , 28 simultaneously pop outwardly within the respective ones of the recesses 55 , 55 to lock the cable terminating assembly 12 against axial movement onto the guide posts 20 , 20 relative to the header 6 . As seen in FIG. 1, latches 28 do not extend outwardly past posts 20 . In other words, latches 28 remain between posts 20 .
In accordance with another feature of the invention, the spring latches 28 , 28 are outwardly bowed at portions 60 , 60 along their length. This bowed portion of the length of each of the spring latches 28 , 28 coincides with inwardly directed bow-cuts 62 , 62 formed in the body 7 of the cable terminating assembly 12 which allows the cable terminating assembly 12 to be readily and quickly removed from the posts 20 by simply squeezing the two opposing spring latches together toward the indicated central axis CA. In this way, a quick release mechanism is provided without the need of additional mechanisms, such as for example, a housing slide. It should further be appreciated that the connection that is described herein requires no tools to effect connecting and disconnecting the cable terminating assembly 12 with the header 6 . In addition, the axial movement of the cable terminating assembly 12 along the central axis CA ultimately results in the spring latches 28 , 28 resiling into the recesses 55 , 55 formed on the guide posts 20 , 20 . This resiliency creates an audible click upon contact with posts 20 which provides the user with a signal indicating that a positive locked condition has been attained which is desirable in the field as previously discussed.
Accordingly, the present invention has been described by way of the illustrated embodiment. However, numerous modifications and substitutions may be had without departing from the spirit of the invention. For example, while the guide posts 20 , 20 are disclosed in the preferred embodiment as being cylindrical members, it is well within the purview of the invention to form such posts, for example, with square cross sectional configurations and to form corresponding shaped bearing surfaces on the journaling parts 40 , 40 in a like manner.
Accordingly, the invention has been described by way of illustration rather than limitation. | A connection between a one and another electrical connector uses a cable terminating assembly with at least one sidewall compartment in which a terminal end of a latch element is disposed. The terminal end of the latch element has a bell shaped cut out formed in it which cooperates with a guide post associated with the other of said connectors so that upon movement of the two connectors toward one another in locking engagement between the two is effected by the continued axial movement of the two connectors. Disconnect is accomplished by simply squeezing the latch elements to effect disengagement from the guide posts. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to an apparatus and method of use for a new simply constructed bioreactor made at least partially of gas permeable materials. The bioreactor is useful for culturing cells and tissues in suspension in a liquid nutrient medium with minimum turbulence. The bioreactor may include ports for easy access to the vessel culture, allowing the growth substrate to be varied for optimum performance.
A primary use is in research where large numbers of cells are grown to refine the minute quantities of an active material (e.g., proteins) that the cells might secrete. Another use of bioreactors is the scale-up of laboratory cell culture processes for commercial purposes to mass produce the active proteins made by genetically engineered cells. Because of the need to culture mammalian cells in the laboratory in large quantities, bioreactors have become an important tool in research and production of cells that produce active proteins.
A current problem in tissue culture technology is the unavailability of an inexpensive bioreactor for the in vitro cultivation of cells and explants that allows easy access to the materials contained in the vessel. Several devices presently on the market have been used with considerable success, but each has its limitations which restrict usefulness and versatility.
Cell culturing devices range upward in complexity from the petri dish, to plastic flasks, to sophisticated computer controlled bioreactors. In the past, manufacturers have promoted various technologies to culture cells in the laboratory. Simple adaptations of fermentors (stirred tanks) used for the culture of bacteria were marketed previously as the answer to culturing delicate mammalian cells. One of the principal factors limiting the performance of these systems is their inability to minimize turbulence due to stirring, i.e., shear due to fluid flow, and hence preventing free form association of cells in three dimensions.
Another utilized technology is microcarrier cell culture, which involves the use of substrate particles, generally collagen-coated beads, to culture anchorage dependent cells. Bioreactors for microcarrier or suspension cells must suspend the cells and substrate in a fluid medium. In the past, this generally was done with an impeller in a stirred tank. Oxygen was provided by sparging (i.e., bubbling) air through the liquid medium. Both the impeller and the bubbling air, unfortunately, create turbulence.
In recent years, a variety of devices have been designed involving horizontal rotating vessels for the suspension of solids in liquid slurries, including bioreactors for cell culture. The primary inventor of the present invention was a co-inventor on six prior patents involving bioreactor systems or methods. They are as follows: U.S. Pat. No. 5,155,035, Schwarz, et al., "Method For Culturing Mammalian Cells In A Perfused Bioreactor" issued Oct. 13, 1992; U.S. Pat. No. 5,155,034, Wolf, et al., "Three-Dimensional Cell To Tissue Assembly Process" issued Oct. 13, 1992; U.S. Pat. No. 5,153,133, Schwarz, et al., "Method For Culturing Mammalian Cells In A Horizontally Rotated Bioreactor", issued Oct. 6, 1992; U.S. Pat. No. 5,153,131, Wolf, et al., "High Aspect Vessel And Method Of Use", issued Oct. 6, 1992; U.S. Pat. No. 5,026,650, Schwarz, et al., "Horizontally Rotated Cell Culture System With A Coaxial Tubular Oxygenator", issued Jun. 5, 1991; and U.S. Pat. No. 4,988,623, Schwarz, et al., "Rotating Bio-Reactor Cell Culture Apparatus", issued Jan. 29, 1991. These patents are incorporated herein by reference as if set out fully verbatim. U.S. Pat. No. 5,153,132, Goodwin, et al., "Three-Dimensional Co-Culture Process", issued Oct. 6, 1992, is closely related to this group of patents, and is also incorporated herein fully as if set out verbatim.
These prior patents disclose apparatuses that use either an internal cylindrical oxygenator or a flat disk shaped oxygenator membrane inserted internally between two pieces of the vessel. Both types of vessels require oxygen injectors.
Specifically, U.S. Pat. Nos. 4,988,623; 5,153,133; and 5,155,034 disclose culture vessels, allowing three-dimensional cell growth, that are shaped similarly to each other due to a central tubular member that functions as a membrane to allow air to be injected through the tubular membrane and into the fluid medium. These patents also disclose internal circularly disposed sets of blade members that rotate around the central horizontal axis, to move the fluid medium within the culture vessel. The apparatus disclosed in U.S. Pat. No. 5,026,650 is similar to the first three patents, but does not contain the blades that move the fluid medium.
U.S. Pat. No. 5,153,131 discloses a bioreactor vessel without mixing blades or a central tubular membrane. This apparatus still requires injection of air into the bioreactor vessel. Air travels through an air inlet passageway, through a support plate member, through a screen and filter cloth, and through a flat disk permeable membrane wedged between the two sides of the vessel housing. The construction of either the tubular membrane or the flat disk one is expensive in terms of the raw materials used (silicone rubber) and the manufacturing process. These membranes are delicate, difficult to install, and require servicing and testing to insure they are free of leaks. A single small hole in the membrane admits air in minute quantities, which forms into air bubbles. As mentioned above, even one air bubble causes damaging turbulence which inhibits or prevents cell growth.
Furthermore, the flat disk membrane in U.S. Pat. No. 5,153,131 flexes to cause mixing(col. 8,line 63 to col. 9, line 5), which is stated to be critical for the distribution of air throughout the culture media. This mixing effect, however, disrupts three dimensional cell growth. The simulation of the zero gravity environment that this design supposedly offers is incomplete because membrane flexing would not occur in a truly zero gravity environment, such as aboard the Space Shuttle in orbit around the earth. Consequently, an improved method of suspending particles(cells and their substrate) that minimizes fluid turbulence, while at the same time providing the required oxygen transfer, is needed to improve the performance of bioreactors. It is an object of the present invention to provide both an apparatus and a method for culturing cells that overcomes the technological limitations of prior bioreactor systems.
SUMMARY OF THE INVENTION
The present invention is directed to a new class of bioreactor for cell culture and a method for use of the bioreactor, whereby the preferred embodiment of the apparatus is a gas permeable bioreactor comprising a tubular vessel with walls constructed at least partially of a gas permeable material. The tubular vessel has closed ends, a substantially horizontal longitudinal central axis, and one or more vessel access ports for transferring materials into and out of the tubular vessel. Means is provided for rotating the vessel about its horizontal longitudinal central axis.
In another preferred embodiment of the apparatus of this invention, the gas permeable bioreactor is a tubular vessel with walls constructed at least partially of a gas permeable material. It has closed ends, a substantially horizontal longitudinal central axis, and is constructed of two sliding members. A first sliding member fits slidably into a second sliding member, forming a liquid tight seal therebetween. The vessel also has means for rotating it about its horizontal longitudinal central axis. One or more access ports are provided on the vessel for transferring materials into and out of said vessel.
An alternative embodiment of the bioreactor of the present invention is an annular vessel with walls constructed at least partially of a gas permeable material. The annular vessel has closed ends, which leaves the central portion of the vessel open. The annular vessel rotates around a substantially horizontal longitudinal central axis and has means for rotating the vessel. One or more access ports are provided for transferring materials into and out of the vessel.
The bioreactor of the present invention is constructed at least partially of a gas permeable material, such as, but not limited to, silicone rubber, polytetrafluoroethylene (teflon®, a registered mark of DuPont), polyethylene, porous polytetrafluoroethylene, other porous plastics, porous plastics coated with a hydrophobic material, mixtures of silicone rubber with other plastics, or silicone rubber coated cloth. In one preferred embodiment of the present invention the vessel is formed of injection molded gas permeable plastic.
It is an object of the present invention to provide a bioreactor vessel that uses only horizontal rotation (clinostatic suspension) to suspend particles in a culture vessel. This is an advantage over the prior art, which required stirring or mixing for particle suspension and oxygenation. The bioreactor of this invention, in contrast, provides a very low turbulence regime. The present invention also overcomes the prior art need for air injection into the bioreactor vessel. The use of air injection is not excluded from the present invention, however. The gas permeable material of which the bioreactor of this invention is constructed provides this advantage by allowing O 2 to diffuse through the vessel walls and into the cell culture media in the vessel chamber. Correspondingly, CO 2 diffuses through the walls and out of the vessel. Clinostatic suspension combined with oxygenation by diffusion merges ideal properties for a high performance bioreactor vessel.
It is another object of the present invention to provide a bioreactor vessel that is disposable. Due to the present bioreactor's simple design and construction, it can be easily and economically manufactured. The resulting bioreactor is consequently affordable, disposable, and may be mass produced. In situations where minimization of contamination is necessary (e.g., AIDS or human tissue research), disposability of the bioreactor is a particular advantage. While the bioreactor may be produced in a wide variety of sizes, its simple construction provides the advantage of allowing bioreactors to be made smaller than previously possible. The smaller sizes are helpful in research laboratories, in particular. Moreover, the embodiment of the bioreactor with two slidably interconnected members may be adjusted to provide the exact size bioreactor needed.
Another aspect of the present invention is a method for growing cells in a gas permeable bioreactor. The method involves filling a bioreactor constructed at least partially of a gas permeable material with a liquid culture medium and cells; suspending said cells, without appreciable mixing, in the cell medium by rotating the bioreactor about its horizontal longitudinal central axis at a rate that suspends the cells in the liquid culture medium. The rotation is continued for a time period to permit desired cell growth. An alternative embodiment of the method of this invention includes adding a growth substrate, such as substrate particles or tissue explants, to the bioreactor with the culture medium and cells.
Still other objects, features and advantages of the present invention will be apparent from the following description of the preferred embodiments given for the purpose of disclosure and taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially cross-sectional side view of a preferred embodiment of the gas permeable bioreactor of the present invention showing attachment to a motor assembly unit for rotation purposes and showing a cross-section of the bioreactor vessel.
FIG. 2 is a cross-sectional side view of another preferred embodiment of the bioreactor having two slidably interconnected members to provide a variable volume vessel. The bioreactor is shown in the open position.
FIG. 3 is a cross-sectional side view of the bioreactor shown in FIG. 2 in the closed position.
FIG. 4 is a cross-sectional side view of an alternative embodiment of the bioreactor of the present invention which has an annular tubular shape.
FIG. 4A is an end view of the embodiment of the annular tubular bioreactor of FIG. 4 taken along the line 4A'--4A'.
FIG. 5 is a cross-sectional side view of another preferred embodiment of the bioreactor with clear microscope viewports on each end of the vessel.
FIG. 5A is an end view of the embodiment of the tubular bioreactor of FIG. 5 taken along the line 5A'--5A'.
FIG. 6 is a cross-sectional partially expanded side view of an alternative embodiment of the bioreactor where multiple bioreactors are attached to each other end to end.
FIG. 7 is an alternative embodiment of the gas permeable bioreactor with an internal membrane dividing the vessel into two chambers, one for cell culture and one for exchanging cell medium without disturbing the cells in the other chamber.
FIG. 8 is a perspective view of a preferred embodiment of a roller mechanism used to rotate one or more bioreactors, showing three bioreactors attached end-to-end and rotating thereon.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, FIG. 1 is a cross-sectional side view of a preferred embodiment of the gas permeable bioreactor of the present invention showing a motor assembly unit for rotation purposes. In the preferred embodiment of the invention, the bioreactor 2 is made of a tubular vessel 4 with outer walls 24 constructed at least partially of a gas permeable materials 6 definig a vessel chamber. The walls 24 themselves may be constructed of the gas permeable material 6 or the material 6 may be made a part of the walls 24 in the same manner as the microscope viewports 50 discussed below. The vessel 4 has closed ends 8 and a substantially horizontal longitudinal central axis 10. One or more vessel access ports 18 are provided for transferring materials into and out of the vessel 4. The vessel 4 in one preferred embodiment is constructed such that half of it is comprised of gas permeable material 6 and the remaining portion is made of nonpermeable material 7.
The gas permeable materials 6 commonly available are opaque. Thus, using nonpermeable material 7 for part of the bioreactor 2 may provide an advantage in allowing visual inspection of the tubular vessel chamber. To further enhance oxygen absorption into the tubular vessel chamber, depressions 22 may be formed in the walls 24 in areas where there is gas permeable material 6. The thinner the wall 24, the less distance the oxygen must travel before entering the tubular vessel chamber. The gas permeable material 6 used to make the bioreactor 2 preferably is a porous, hydrophobic material. It may be a porous nonhydrophobic material coated on one side with silicone rubber or some other hydrophobic material to achieve gas permeability. However, if the pore size of the porous material is one micron or less, a coating is not preferred. In the preferred embodiment, the porous material used is a "foamed" plastic, which is a hardened porous plastic. This porous plastic is available commercially in a variety of pore sizes from companies such as Porex Technologies (located in Fairburn, Ga.). For instance, Porex manufactures products in porous polytetrafluoroethylene and polyethylene that are suitable for use in this invention.
Any nonpermeable material 7 used to construct the walls 24 preferably is a transparent, nontoxic, biocompatible material such as clear plastic. Most preferably the clear material is polycarbonate (also known as Lexan®, a registered trademark of General Electric).
The bioreactor 2, furthermore, may be made of a variety of materials: silicone rubber, polytetrafluoroethylene, polyethylene, porous plastic, porous plastic coated with a hydrophobic material, mixtures of silicone rubber with other plastics, and silicone rubber coated cloth. Preferably, the bioreactor 2 is constructed of porous plastic coated with a hydrophobic material on the interior surface. Most preferably, the vessel 4 is made of porous hydrophobic teflon. The vessel 4 may also be formed out of injection molded plastic. When injection molded plastic is used, the molded pieces of the tubular vessel 4 may be welded, glued, or mechanically attached together. Preferably, the tubular vessel is made in two pieces which are welded, glued, or mechanically attached together around a circumferential seam 20, as shown in FIG. 1. Other construction methods may be used, however, such that the tubular vessel 4 may be formed of one piece of molded plastic, thus eliminating the circumferential seam 20. The bioreactor 2 is constructed at least partially of a gas permeable material 6, and the percentage of the tubular vessel made of gas permeable material may vary from about 5% to about 100%. In one preferred embodiment of the bioreactor 2, the vessel 4 is constructed with a first half comprised of gas permeable material 6 and a second half comprised of a non-gas permeable material 7.
The tubular vessel 4 may be made in any size, so long as the surface area to volume ratio of the tubular vessel 4 is large enough to allow adequate gas transfer through the walls 24 to the cell culture in the tubular vessel 4. As a tubular vessel 4 gets larger (by expanding all dimensions proportionally) the volume increases as the cube of its dimensions, whereas the surface area increases as the square of its dimensions. Once a certain size is reached, the reduced surface area per volume will hinder adequate gas transfer. This can be avoided, however, by scaling up the size in one dimension only. For instance, the length of the tubular vessel may be increased but not the diameter, or the diameter may be increased but not the length. For tubular vessels of a size of 500 ml or less, the dimensions of the tubular vessel 4 are not critical.
Additionally, the dimensions and shapes of the tubular vessels 4 are use dependent. The type of cells being grown and the use of substrate carriers affects gas transfer. When the suspension cells are lightweight, they cause little mixing and oxygen must travel further from the wall 24 to the cells. When larger cell colonies are grown on substrate carriers, mixing results such that less gas transfer is required for oxygenation of the cells. The acceptable variations of the dimensions are endless, but those skilled in the art will be able to adjust the dimensions to suit the particular application, while still providing adequate 0 2 transfer.
In the preferred embodiment of the invention, the volumetric size of the tubular vessel chamber 4 is preferably in the range of about 1 ml to about 500 ml. The diameter of the tubular vessel 4 preferably is in the range of about 1 inch to about 6 inches. The most preferred range of diameters is in the range of about 3 inches to about 6 inches.
The width of the bioreactor 2, due to the permeability of the walls 24, may be doubled relative to widths in prior art designs, since gas can be transferred from all tubular vessel surfaces. For cells in free suspension (very small particles which do not settle quickly) the preferred chamber width is about 1/4 inch but may be in the range of about 1/8 inch to about 1 inch. While the volume of the tubular vessel chamber may be any size, it should be kept in mind that the bioreactor 2 produces at least 10 to 20 million cells per milliliter. Thus, a tubular vessel 4 of 2.0 liters would allow growth of approximately 20 billion cells. An advantage of this productivity, is that smaller tubular vessels 4 may be used than ever before.
A preferred means for rotation is a motor assembly 12 as shown in FIG. 1. The motor assembly 12 sits on a mounting base 14 and has means 16 for attachment to the tubular vessel 4. Preferably, the means for attachment 16 comprises threadably connecting the tubular vessel 4 to the motor assembly 12 through screw threads on the drive shaft corresponding to screw threads on the tubular vessel 4. Preferably, these screw threads are in a direction such that inadvertent loosening of the tubular vessel 4 from the motor assembly 12 due to the movement of rotation is avoided. In addition, a lock nut or similar device may be provided on the drive shaft to prevent unscrewing. In the preferred embodiment, a 5/8 inch threaded shaft coupling is used, but this may be varied to coordinate with the size of the bioreactor 2.
The means for rotation in one preferred embodiment is a roller mechanism 70 as shown in FIG. 8. The roller mechanism 70 has multiple rollers 74 stretched longitudinally in a horizontal plane which rotate simultaneously to correspondingly rotate any bioreactor 2 laid on the roller mechanism 70. Such roller mechanisms 70 are commercially available. The bioreactor 2 of the present invention may be rotated on a roller mechanism 70 such as the ones produced by Stoval Life Science, Inc. Stoval manufactures compact, nondedicated roller units which perform multiple functions in the biological research laboratory. It operates on benchtops, in high humidity and carbon dioxide incubators, high temperature ovens (to 65° C.), and in refrigerated units (0° C.). The roller mechanism 70 has speed control operated by a speed control knob 72. Other roller mechanisms 70, of course, may be utilized as will be commonly known to those skilled in the art. The bioreactor 2 of the present invention may also be constructed with means 52 on each end 8 for attaching one tubular vessel 4 to an additional tubular vessel 4, thereby creating a chain of bioreactors 2. One or more vessel access ports 18 are provided for transferring materials into and out of the tubular vessel chamber 4.
The preferred speed of rotation is in the range of about 2.0 rpms to about 40 rpm and is largely dependent on the specific bioreactor and what is being cultured. For example, for a bioreactor of about 3 to 5 inches in diameter, with a width of about 0.25 inches, growing BHK-21 cells in a microcarrier culture, the preferred speed of rotation is about 24 rpm. Speed must be adjusted to balance the gravitational force against the centrifugal force caused by the rotation. For tubular vessels of up to about 5 inches in diameter, the rotational speed may range from about 2 rpm for single cells in suspension, up to about 40 rpm for large particles grown on microcarrier substrates.
As shown in FIG. 1, the vessel access ports 18 provide access to the bioreactor 2 for input of medium and cells and for removal of old medium from the tubular vessel 4. This is easily done through the vessel access ports 18, which are also referred to as valves or syringe ports. In the preferred embodiment, the vessel access ports 18 are constructed of valves with syringe ports. The valves preferably are plastic, but may be made of metal or any other material which is hard enough for machining into an access port and is non-toxic. The carbon dioxide produced by the cells when they use oxygen and metabolize sugar leaves the tubular vessel chamber primarily by traveling out through the gas permeable wall 24 of the tubular vessel 4.
Another advantage of the new bioreactor 2 is that air filters for the O 2 source are unnecessary, as previously required. The prior art bioreactors required an air filter to protect the air pump valves from dirt. The bioreactor 2 of the present invention relies on the rotation of the tubular vessel 4 to circulate fresh air over its surface.
In an alternative embodiment of the bioreactor 2, as shown in FIG. 7, a permeable membrane 60 is inserted into the tubular vessel 4 in a plane substantially perpendicular to the horizontal axis 10 to separate the tubular vessel 4 into two chambers: a cell growth chamber 58 and a reservoir chamber 56. It should be noted, however, that the two chambers 58, 56 are functionally interchangeable, i.e., either one may be used for cell growth. The cell growth chamber 58 preferably is used for cell culture. The reservoir chamber 56 may be filled and refilled with fresh medium without disturbing the cell culture in the cell growth chamber 58. The membrane 60 has a porosity that allows medium and metabolic waste to travel through it, but cells and substrates are too large to do so. Thus, this embodiment of the invention allows greater freedom in replacing the cell medium, particularly when the cell culture is producing large amounts of waste metabolites. In some past systems, it was necessary to centrifuge the cell culture to separate the cells from the medium in order to accomplish a change of the medium. This embodiment of the invention avoids the need to centrifuge the cell culture suspension.
In the preferred embodiment of the invention, the bioreactor 2 is made of a tubular vessel 4 with walls 24 constructed at least partially of a gas permeable material 6. The tubular vessel chamber 4 in one preferred embodiment is constructed such that,half of it is comprised of gas permeable material 6 and the remaining portion is made of nonpermeable material 7. The tubular vessel chamber 4 has closed ends 8, one of which is provided with a means 16 for attachment to a motor assembly not shown. In this embodiment of the invention, four vessel access ports 18 are used to allow access to the contents of the tubular vessel 4 on each side of the membrane 60. Furthermore, a seam bracket 54 between two pieces of the tubular vessel 4 may be used to attach the membrane 60 across the tubular vessel 4. Alternatively, the membrane may be glued, welded, or mechanically attached between the pieces of the tubular vessel 4.
Another feature of the present invention is a microscope viewport 50 which may be incorporated into the walls 24. FIGS. 5 and 5A portray a bioreactor 2 of the present invention made entirely of gas permeable material 6, except for microscope viewports 50 which are incorporated on each end 8 of the tubular vessel 4. The viewports 50 may be glued, welded, or mechanically attached to the ends 8. Moreover, as shown in FIG. 5., the ends 8 may be formed to provide shoulders 51 for the viewports 50 to rest against and be attached to. Preferably, two microscope viewports 50 are incorporated into the walls 4 opposite to each other, so that the microscope will have a clear viewing path through the tubular vessel 4. FIG. 5A is an end view of the bioreactor 2 of FIG. 5 taken along the line 5A'--5A'. The tubular vessel chamber 4 in one preferred embodiment as shown in FIGS. 5 and 5A is constructed such that half of it is comprised of a gas permeable material 6 and the remaining portion is made of nonpermeable material 7. The tubular vessel chamber 4 has closed ends 8 and a substantially horizontal longitudinal central axis 10. One or more vessel access ports 18 are provided for transferring materials into and out of the tubular vessel chamber 4. In addition, a shoulder 37 may provide a resting place for the drive shaft (not shown) to rest against the connected tubular vessel 4.
As shown in FIG. 6, the bioreactor 2 of the present invention may also be constructed with means 52 on each end 8 for attaching one tubular vessel 4 to an additional tubular vessel 4, thereby creating a chain of bioreactors 2. When a chain of bioreactors 2 is formed in this manner, the chain may be attached to a means for rotation at one of its ends 8. If a motor assembly is used for rotation of the chain of bioreactors 2, the vessel access port 18 may be located on the circumferential perimeter of the tubular vessel 4 for easier access. However, if the chain of bioreactors 2 as shown in FIG. 6 is to be rotated on a roller mechanism 70 as shown in FIG 8, for example, the vessel access ports 18 should be located on the tubular vessel 4 ends 8. In the preferred embodiment of the invention, and as shown in FIG. 6, the bioreactor 2 is made of a tubular vessel 4 with walls 24 constructed at least partially of a gas permeable material 6. The tubular vessel chamber 4 has closed ends 8 and a substantially horizontal longitudinal central axis 10. The tubular vessel 4 has means 16 for attachment to a motor assembly, not shown. Preferably, the tubular vessel 4 is made in two pieces which are welded, glued, or mechanically attached together around a circumferential seam 20.
The present invention also includes a bioreactor 2 with a variable volume, as shown in FIGS. 2 and 3. In this embodiment of the bioreactor 2, the bioreactor 2 is comprised of a tubular vessel 4 constructed at least partially of a gas permeable material 6. The vessel 4 has closed ends 8 and a substantially horizontal longitudinal central axis 10 around which it rotates. The vessel 4, furthermore, has two slidably interconnected members 30, 32, wherein a first member 30 fits slidably into a second member 32, forming a liquid tight seal 34 therebetween and providing a variable volume tubular vessel 4. The bioreactor 2 has means for rotating the tubular vessel 4 about its substantially horizontal longitudinal central axis 10. One or more vessel access ports 18 are provided for transferring materials into and out of the vessel 4. In the embodiment of the invention shown in FIGS. 2 and 3, the bioreactor 2 is made of a tubular vessel 4 with walls 24 constructed at least partially of a gas permeable material 6. The tubular vessel chamber 4 in one preferred embodiment is constructed such that half of it is comprised of gas permeable material 6 and the remaining portion is made of nonpermeable material 7. Preferably, screw threads 38 are provided on the tubular vessel 4 for connecting the tubular vessel 4 to a motor assembly not shown.
Where the variable volume embodiment of the bioreactor 2 is rotated by attachment to a motor assembly that occludes the open end of the first member 30, air ports 36 may be added to the first member 30 to assist with O 2 transfer into the tubular vessel chamber. In addition, a shoulder 37 on the first slidably interconnected member 30 may provide a resting place for the drive shaft to rest against when threadably connected to the screw threads in the end 8 of the member 30.
This embodiment of the bioreactor may be made of the same materials as described above for the other embodiments of the bioreactor 2. Preferably, the first tubular member 30 is formed of gas permeable material 6, and the second tubular member 32 is formed of a clear, non-toxic, biocompatible material.
The same means for rotating the tubular vessel 4 may be used as described above, and most preferably by the motor assembly 12 shown in FIG. 1. One or more vessel access ports 18 for transferring materials into and out of the tubular vessel 4 are located on the end 8 of the tubular vessel 4. The volume of the tubular vessel 4 may be varied by the relative movement of the first and second members 30, 32. The vessel members 30, 32 behave as a sliding plunger assembly, similar to a syringe. The seal 34 on the first slidable interconnected member 30 preferably is a rubber gasket, such as an O ring, which may be fitted into a depression around the circumference of the first member 30 near its end 8. The opposing end of the first member 30 is open to allow air or other gases to move freely inside the member 30.
An alternative embodiment of the bioreactor of the present invention, as shown in FIGS. 4 and 4A, comprises an annular tubular vessel 40 with walls 24 constructed at least partially of a gas permeable material 6 defining an annular vessel chamber 42. It is constructed similarly to the embodiments of the invention described above and varies primarily in its shape. Annular is defined herein to include annular, toroidal, and other substantially symmetrical ring-like shaped tubular vessels 40. The annular vessel 40 has closed ends 8 and a substantially horizontal longitudinal central axis 10. The central portion 44 of the tubular vessel 40, consequently, is left open, allowing air to flow over the central portion 44 of the tubular vessel 40. FIG. 4A is an end view of the embodiment of the bioreactor of FIG. 4 taken along line 4A'--4A'.
Means for rotating the annular tubular vessel 40 about its substantially horizontal longitudinal central axis 10 is preferably a motor assembly 12 as depicted in FIG. 1. Screw threads may be provided in the walls 24 of one end 8 of the central portion 44 of the tubular vessel 40. Other means for rotating the tubular vessel may be used, however, as described above. Two vessel access ports 18, preferably are provided on one end 8 of the tubular vessel 40 to allow cells, medium, and other materials to be transferred into and out of the tubular vessel 40.
Another aspect of the present invention is a method for growing cells in a bioreactor 2 comprising filling a bioreactor 2 constructed at least partially of a gas permeable material 6 with a liquid culture medium and cells; suspending the cells, without appreciable mixing, in the cell medium by rotating the bioreactor 2 about its substantially horizontal longitudinal central axis at a rate that suspends the cells in the liquid culture medium; and continuing rotation of the bioreactor 2 for a time period that permits a desired cell growth.
Referring again to FIG. 1, the bioreactor 2, after sterilization, is filled with a liquid culture medium, such as those commonly known in the art, and cells. If desired, substrate particles may also be added. One preferred microcarrier substrate is collagen coated beads, but numerous types of substrate particles may be used and are known by those skilled in the art. Alternatively, the substrate particles may be pieces of tissue explant. Tissue explant may be diced and added to the culture medium as a substrate upon which cells grow. In addition, tissue explant may be added to a cell culture medium without the addition of other cells. Then, the explant is cultured for further cell growth. In this situation, the tissue explant takes the place functionally of both the cells and the substrate.
Once the tubular vessel 4 is completely filled with medium and any other materials, such that no air spaces exist in the tubular vessel, the cells (or tissue explant if it is cultured instead) are suspended in the bioreactor 2 without any appreciable mixing by rotating the bioreactor 2 about its horizontal longitudinal central axis 10 at a rate that suspends the cells in the liquid culture medium. The appropriate rate of rotation is discussed above.
Rotation of the tubular vessel 4 preferably takes place in the presence of an oxygen containing gas mixture with about 5% carbon dioxide. In the preferred method, the gas mixture is air. In addition, the bioreactor 2 is preferably rotated within an incubator to control the temperature of the tubular vessel 4 culture. The temperature preferably ranges from about 35° C. to about 40° C. for mammalian cells. For any cell, of course, the temperature preferably is maintained at a level that permits cell growth. The rotation of the tubular vessel is continued until the desired amount of cell growth occurs.
During rotation, the oxygen containing gas mixture diffuses through the permeable tubular vessel 4 walls 24 and into the liquid culture medium in the chamber. Carbon dioxide produced by cellular metabolism diffuses through the medium and the walls 24 and is thus eliminated from the chamber. Moreover, the vessel access ports 18 allow the medium in the tubular vessel 4 to be exchanged regularly, if desired. In cases where cells are cultured over longer periods of time, exchanging used culture medium for fresh culture medium becomes more important. Once desired cell growth is obtained, the tubular vessel 4 may be detached from the means for rotation and the cells culture medium may be decanted from the tubular vessel 4 for harvesting of the cells.
The method of the present invention may also be utilized with other embodiments of the bioreactor 2 of the present invention. Such embodiments are described above and claimed herein.
Notwithstanding that the invention is described in terms of particular preferred embodiments, it will be understood that the present invention is not to be construed as limited to such, rather to the lawful scope of the appended claims. | A new rotating cell vessel and method of use have been developed. The vessel is constructed of materials which are permeable to oxygen and carbon dioxide, and when rotated horizontally suspend the contents, cells and particle substrates, in a liquid medium with a low turbulence, low shear fluid environment. The vessel walls are made at least partially of gas permeable material. The vessel is rotated in a horizontal plane to suspend the cells and substrate particles in a low turbulence liquid nutrient medium. Oxygen continuously diffuses through the permeable vessel material and through the cell culture liquid medium to provide the needed oxygen to the cells. Carbon dioxide diffuses through the cell culture medium and through the vessel wall, removing this waste product from the cell culture. The vessel is uniquely designed to be simply constructed. | 8 |
This nonprovisional application is a continuation of International Application No. PCT/EP2009/001691, which was filed on Mar. 10, 2009, and which claims priority to German Patent Application No. DE 10 2008 015 141.6, which was filed in Germany on Mar. 20, 2008, and which are both herein incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to roller grinding mills.
2. Description of the Background Art
Roller grinding mills have been known for more than a hundred years, and are used throughout the world. They exist in an extremely wide variety of designs. Thus, for example, DE 153 958 C from 1902 shows a cone mill with a revolving grinding plate on which rest eight grinding cones under spring pressure.
Modern mills use grinding rollers that have heavy weights and large diameters to achieve high milling output. Please see DE 198 26 324 C, DE 196 03 655 A, which corresponds to U.S. Pat. No. 6,021,968, and also EP 0 406 644 B. This type of roller grinding mill has gained extremely wide acceptance in practice because it has considerable advantages with regard to design, control, and energy economy. The chief areas of application for modern roller grinding mills are the cement industry and coal-fired power plants. In the cement industry, roller grinding mills are used for producing raw cement meal as well as for clinker grinding and coal grinding. In combination with rotary kilns and calcining installations, the furnace exhaust gases from the heat exchanger and clinker cooler can be used to dry the grinding stock and pneumatically transport the ground stock. In power plants, the roller grinding mills are used to finely grind the coal and feed it directly into the boiler with the aid of the classifier air, if possible without the use of an intermediate bunker.
Modern large mills require drive power levels of up to 10 MW. It is a matter of course that the associated bearings and drives, in particular the transmissions, must be of special design. The teeth, the shaft bearings, the integrated axial thrust bearings and their supports within the transmission housing, are particularly heavily loaded. For drive power levels up to 6 MW, planetary bevel gear transmissions, which are matched to the circular grinding plate on account of their circular shape, have become established as the state of the art; they transmit the static and dynamic grinding forces to the foundation. Please see DE 35 07 913 A or DE 37 12 562 C, which corresponds to U.S. Pat. No. 4,887,489. Pivoted-pad bearings with hydrodynamic and/or hydrostatic lubrication are used as axial thrust bearings; please see DE 33 20 037 C.
These designs, space-saving in and of themselves, have significant disadvantages, however. As soon as a problem arises with just one component, the entire drive must be dismantled. It has proven to be particularly disadvantageous in this regard that it is extremely difficult to visually inspect the gears of the planetary transmission; oftentimes, this is not possible until the drive has been dismantled completely. Since these drives are special designs, procurement of replacement parts takes a commensurately long time, i.e., weeks or months, since stocking of replacement parts is considered too cost-intensive on account of the special designs. This is unsatisfactory.
Another disadvantage of the prior art drive design is what is called the maintenance drive, which rotates the grinding plate during certain maintenance and repair operations, but which only functions as long as the primary transmission itself functions.
Naturally, there has been no shortage of proposals for doing away with these inadequacies and disadvantages. Thus, DE 39 31 116 C shows a drive device for a roller grinding mill having a grinding plate that can rotate about a vertical axis, which has a crown gear connected to the lower part of the grinding plate. Moreover, two diagonally arranged drives are provided, each having a drive motor and a gear reducer. Each gear reducer has two pinions that mesh with the crown gear of the grinding plate.
Known from DE 76 29 223 U is a roller grinding mill with a ring gear located under its grinding plate. The pinions of four hydraulic motors fastened to the base of the mill housing mesh with the ring gear.
Despite the theoretical advantages of these multiple-motor drive concepts, they have as yet been unable to gain acceptance in practice. In the case of hydraulic drives, the lower efficiency as compared with electric drives, and the lower availability and service life of the hydraulic components are disadvantages. The previously described dual-drive concept with electric motors and gear reducer was unable to gain acceptance because considerable excess torques arise during operation, which can result in overloading of the transmission to the point of destruction. Moreover, it was not possible to support mill operation with the required capacity in the event of the failure of a drive.
However, it is not only the required drive power level that has increased with the increasing capacity of roller grinding mills, but also the number of grinding rollers rolling on the grinding plate. Thus, DE 103 43 218 B4, which corresponds to U.S. Publication NO. 20080245907, describes a roller grinding mill with six grinding rollers and a single drive. Here, the design is arranged such that two diagonally opposite grinding rollers can be pivoted out simultaneously, and the mill is intended to produce 80% of the full milling output with the remaining four active grinding rollers. A disadvantage in this design is that two grinding rollers always have to be pivoted out, even when only one grinding roller has failed.
DE-OS 21 24 521 has also already described a roller grinding mill with six grinding rollers.
Finally, a roller grinding mill with four grinding rollers is known from DE 197 02 854 A1, in which each grinding roller is driven by a separate drive, having an electric motor and gear reducer. The grinding plate itself does not have a drive. No provision is made for deactivation of one or more grinding rollers or of one or more drives.
SUMMARY OF THE INVENTION
The object of the present invention is to specify roller grinding mills with at least two grinding rollers and at least two drives, in which only low forces, which do not overload the radial bearing, arise on the radial bearing of the grinding plate when a single grinding roller is deactivated.
If, in contrast to the teaching in the above cited DE 103 43 218 B4, one removes just a single grinding roller rather than two diagonally opposite grinding rollers, then a substantial radial force component acts on the grinding plate, produced by the remaining grinding rollers. This radial force component loads the axial and, in particular, the radial bearing of the grinding plate to a substantial degree. The bearing of the grinding plate would thus have to be considerably oversized. However, it has been found that this is not necessary, or is necessary only to a significantly reduced degree, if, in accordance with the invention, the grinding plate is driven by multiple drives distributed about its circumference, and the matching drive is deactivated at the same time as the grinding roller. The term “matching drive” is understood to mean the drive for which only a minimal resultant radial force arises on its deactivation.
It is a matter of course that the same beneficial effect is also achieved if the matching grinding roller is deactivated when a drive fails.
When a grinding roller fails and the corresponding drive is then removed, the milling output would normally drop accordingly. Now, it is known that the milling output can be increased by increasing the contact force and boosting the classifier air. However, this would nullify the compensating effect achieved by removing the drive. The solution to this problem is to raise the drive force of the remaining drives along with increasing the contact force of the grinding rollers in order to achieve the necessary throughput.
According to an embodiment of the invention, the grinding plate is equipped with a crown gear, which the drives act upon.
To make it possible to lift the grinding rollers individually from the grinding track and pivot them out of the mill, they are mounted by means of rocker arms on brackets standing next to the mill housing.
The deactivation of a drive can be accomplished in the simplest case by switching off the drive energy, for example the electric power, so that the transmission and motor run idle.
However, it is more advantageous if the drive is decoupled from the grinding plate. According to one embodiment, the drives can travel on carriages or rails for this purpose.
Surprisingly, it has been found that the radial force component remaining when a drive and a grinding roller are deactivated can be reduced still further if the angle between the grinding rollers and the drives is changed. To this end, the angular positions of the drives are adjustable about the center of the mill.
Another embodiment of the invention provides for compensating the radial force component arising when a grinding roller or drive fails by the means that the remaining grinding rollers themselves generate an opposing force component. To this end, according to one embodiment of the invention the grinding rollers can be set at an angle, i.e. rotated with respect to the tangential position.
A further development of the invention provides for the number of drives to be equal to the number of grinding rollers.
An especially economical embodiment of the invention provides for the grinding rollers with the rocker arms and the drives to be prefabricated in modular form. A larger or smaller number of roller modules or drive modules are used in accordance with the wishes of the mill operator. In this way, mill components such as grinding rollers, rocker arms, motors and transmissions can be mass-produced and kept in stock for repairs.
An additional object of the invention is a method for operating a roller grinding mill that makes it possible to compensate the radial force component arising when a grinding roller fails, so that overloading of the grinding plate bearing is avoided.
A further reduction in the resultant radial force component is achieved when the angular position of at least one of the remaining drives is changed such that the resultant radial force is minimal.
A final possibility for reducing the radial force component is in setting the remaining grinding rollers at an angle so that the resultant radial force is minimal.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:
FIG. 1 a top view of a roller grinding mill with six grinding rollers pivotably mounted on brackets and six separate drives;
FIG. 2 the radial forces produced during operation of the mill from FIG. 1 under various operating conditions;
FIG. 3 the radial forces produced during operation of a mill with five grinding rollers and five drives;
FIG. 4 the radial forces produced during operation of a roller grinding mill with four grinding rollers and four drives under various operating conditions; and
FIG. 5 the radial forces of a roller grinding mill with three grinding rollers and three drives under various operating conditions.
DETAILED DESCRIPTION
FIG. 1 shows a top view of a roller grinding mill with a rotating grinding plate 1 , upon whose grinding track roll six grinding rollers M. The grinding plate 1 is supported by an axial bearing and a radial bearing 3 . Each grinding roller M is mounted by means of a rocker arm 4 on an external bracket 5 , so that each grinding roller M can be lifted individually from the grinding track and pivoted out of the mill. This makes it possible to carry out maintenance or repair of a grinding roller while milling operation continues.
Also visible between the six grinding rollers M are six drives A, including motors, preferably electric motors, and transmissions. All drives A act on a crown gear (not shown), which is attached to the grinding plate 1 .
In order to be able to decouple the drives A from the grinding plate 1 , they are mounted on carriages or rails (not shown).
FIG. 2 a shows, purely schematically, the mill from FIG. 1 . The grinding plate, on which roll the six grinding rollers, is visible. The grinding plate is driven by the six drives A distributed about the circumference. Since all radial forces mutually compensate one another in this symmetrical arrangement, the resultant radial force R is equal to zero.
FIG. 2 b shows the mill from FIG. 2 a , but with one grinding roller M pivoted out. A resultant radial force component of magnitude R 1 arises.
FIG. 2 c shows the situation when, in addition to the grinding roller M, the adjacent “matching” drive A has been deactivated. The resultant radial force component has been reduced to R 2 <R 1 .
FIG. 2 d shows the situation when, in addition to the action from FIG. 2 c , the angular position of the drive indicated by an arrow is changed. The radial force R 3 has decreased almost to zero.
FIG. 3 a shows, purely schematically, a roller grinding mill that has five grinding rollers M rolling on its grinding plate and that is set in rotation by five drives A. Because of the symmetrical arrangement, the resultant radial force component R=0.
FIG. 3 b shows the situation when one of the grinding rollers M has been pivoted out. A resultant radial force component R 1 arises.
FIG. 3 c shows the situation when, in addition to the grinding roller M, the adjacent “matching” drive A has also been deactivated. In this way, the resultant radial force component has been reduced to R 2 <R 1 .
FIG. 3 d shows the situation when, in addition to the action from FIG. 3 c , the angular position of the drive indicated by an arrow is changed. The radial force R 3 has decreased almost to zero.
FIG. 4 a shows a roller grinding mill whose grinding plate is driven by four drives A, and that has four grinding rollers M rolling on its grinding plate. Because of the symmetrical arrangement, the resultant radial force component R=0.
FIG. 4 b shows the situation when one of the grinding rollers M has been pivoted out. A resultant radial force component of magnitude R 1 arises.
FIG. 4 c shows the situation when, in addition to the grinding roller M, the adjacent drive A has also been deactivated. The resultant radial force component has been reduced to R 2 <R 1 .
FIG. 4 d shows the situation when, in addition to the action from FIG. 4 c , the angular position of the drive indicated by an arrow is changed. The radial force R 3 has decreased almost to zero.
FIG. 5 a shows a roller grinding mill whose grinding plate is driven by three drives A, and that has three grinding rollers M rolling on its grinding plate. Because of the symmetrical arrangement, the resultant radial force component R=0.
FIG. 5 b shows the situation when one of the grinding rollers M has been pivoted out. A resultant radial force component of magnitude R 1 arises.
FIG. 5 c shows the situation when, in addition to the grinding roller M, the adjacent drive A has also been deactivated. In this way, the resultant radial force component has been reduced to R 2 <R 1 .
FIG. 5 d shows the situation when, in addition to the action from FIG. 5 c , the angular position of the drive indicated by an arrow is changed. The radial force R 3 has decreased almost to zero.
The example embodiments from FIGS. 2 a to 5 d show that the invention can be used in all roller grinding mills, regardless of the number of grinding rollers, when the grinding plate is set in rotation by a corresponding number of drives.
Moreover, it is a matter of course that not only one grinding roller and one drive can be deactivated at a time, as shown in the figures. The inventive principle also works when multiple grinding rollers and the “matching” drives are deactivated, with there being no necessity to deactivate only radially opposite units, which obviously would only be possible when an even number of grinding rollers and drives is provided.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims. | A roller grinding mill is provided that includes a grinding plate, grinding rollers, and at least two drives acting upon the grinding plate, and to a method for operating such a roller grinding mill. At least one grinding roller and substantially simultaneously at least one matching drive can be disengaged during operation. Thus only small radial forces are created that effect the radial bearing of the grinding plate. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation-in-part of U.S. patent application Ser. No. 09/808,734 filed on Mar. 15, 2001, which application was a continuation-in-part of U.S. patent application Ser. No. 09/321,896 filed on May 28, 1999, now U.S. Pat. No. 6,204,757, which application was based on U.S. Provisional Application No. 60/087,137 filed on May 29, 1998.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to systems for registering and recording the braking response time and average following distance for operators of commercial or private motor vehicles and other human-operated equipment. In particular, the present invention relates to systems for detecting, monitoring, and storing braking response time and following distance data, as well as other safety parameter data (e.g. acceleration/deceleration), for immediate usage or later retrieval.
2. Description of the Background
Safe operational conditions for any motor vehicle require its operator to exhibit adequate braking response time and reasonable judgement with regard to the distance at which he/she follows the vehicle directly in front. An operator's response time and judgement should not exceed parameters that (1) represent sensible driving tactics based on existing road conditions (i.e. parameters for good versus inclement weather conditions would vary), (2) represent sensible driving tactics based on existing road design (i.e. curving/winding roads, or uphill/downhill sections where the posted speed limit is incompatible with driving in good/excellent weather conditions), (3) may be indicated by excessive brake system wear, and (4) demonstrate that the vehicle has been operated in an unsafe manner.
In order to reduce insurance and other expenses caused by injuries to employees, employers of truck drivers or large commercial equipment operators often set forth safety policies including guidelines for vehicle operation. These typically include guidelines for braking that include parameters such as the weight of the vehicle being operated and the distance at which the vehicle operator follows the vehicle directly ahead. Maintaining an adequate following distance is critical in bringing a vehicle safely to a stop. Additionally, an operator's brake response time (i.e. the time between recognizing/acknowledging that the brakes need to be applied and the moment that the brake system is engaged) must be considered when establishing an appropriate following distance parameter. Unfortunately, the prior art devices lack any method of consistently and accurately measuring and recording an individual's operation of a vehicle, making the policing of any such guidelines extremely difficult.
Systems for monitoring vehicular use are well known in the prior art. For example, U.S. Pat. No. 5,754,964 to Rettig et al. discloses an apparatus and method for storing various vehicle operating characteristics upon sensing a vehicle acceleration having a magnitude that exceeds a predetermined limit. In this manner, the vehicle owner or fleet manager can determine whether the vehicle operator uses the service brakes excessively. While this invention is drawn specifically to the braking process, it does not include means for determining the average or instantaneous following distance to the vehicle immediately ahead or an operator's response time. It also fails to, during the braking event, record the time or position of the vehicle while the acceleration parameter is being measured.
A second example is that of U.S. Pat. No. 5,570,087 to Lemelson. It discloses a system and method for monitoring the performance of a motor vehicle. The vehicle's instantaneous accelerations in at least two directions are continually sensed and stored as coded signals in a computer memory along with associated time and date codes. By means of inertial navigation and/or radio transmissions from global positioning system satellites, the vehicle's global position is also computed and stored. The stored performance variables are analyzed over a period of time in order to evaluate how the vehicle is being driven. When an erratic or otherwise hazardous driving pattern is detected, signals may be generated to warn the driver and/or traffic authorities. However, this system also fails to include means for determining the average or instantaneous following distance to the vehicle immediately ahead or an operator's response time.
In light of the above information, it would, therefore, be advantageous to provide a system for accurately and consistently measuring and recording the brake response time and average following distance for the operators of private/commercial vehicles and heavy equipment. Operational liability could be reduced if unsafe braking practices/habits could be identified and corrected for any given operator, inclusive of factors such as road, vehicle, or weather conditions.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a system for detecting, measuring, and recording the brake response time and average following distance for the operators of private/commercial vehicles and heavy equipment.
It is another object of the present invention to provide a system for measuring and recording other safety-related information in such vehicles, such as date/time of occurrence and vehicle position.
It is a further object of the present invention to organize the data retrieved from the various sources herein described into a usable and consistent record, which can then be compiled with like records to analyze brake response time, following distance, and other safety parameters in a comprehensive and statistical manner.
It is a further object of the present invention to provide the above objects in an economical and facile manner, using existing, commercially available components to the extent practical.
In accordance with the above objects, an improved brake response time and following distance monitoring and safety data accounting system is provided which measures and records events where preset parameters are exceeded. Specifically, the present invention measures and records, among others, parameters associated with instantaneous vehicular following distance, average vehicular following distance, instantaneous changes in following distance, and brake response time of an operator. The system is equipped with data processing and communication means allowing an employer, a parent, an insurance carrier, or any other interested person to verify that the vehicle in question is operated in an appropriate manner. The present invention records each vehicle braking cycle to determine if previously established safe operating parameters were maintained while noting the date, time of day, and location of the incident. The information retrieved is compiled in a data record and stored in a storage system for instantaneous use or retrieval when desired.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiment and certain modifications thereof when taken together with the accompanying drawings in which:
FIG. 1 is a schematic block diagram showing the braking response and following distance monitoring and safety data accounting system 10 according to a preferred embodiment of the present invention.
FIG. 2 is a schematic diagram illustrating the functionality of the electronic data portions of the braking response and following distance monitoring and safety data accounting system 10 according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in the schematic block diagram of FIG. 1, the braking response and following distance monitoring and safety data accounting system 10 of the present invention generally comprises a proximity sensor 15 , a multiple axis accelerometer 20 , a Hall effect sensor 25 , a data acquisition module 40 to receive analog signal inputs from the sensors 15 , 25 and accelerometer 20 , a power supply 30 for the sensors 15 , 25 , accelerometer 20 and module 40 , a direct electrical connection 45 to the vehicle's brake light, a global positioning receiver 50 to record the vehicle location and time reference, processing means 60 programmed to poll the data acquisition module 40 and the global positioning receiver 50 and compile a unified data record, and storage means 70 for storage of the unified data records for later retrieval.
The proximity sensor 15 may be any well-known and commercially available unit which is equipped with appropriate measurement capability. The sensor 15 must be capable of determining the distance to an object positioned directly in front of it. A preferred sensor 15 may be the 77 Ghz., pulsed Doppler, forward looking radar unit commercially available from M/A-COM, although any standard sensor capable of appropriate distance measurement would suffice. The sensor 15 , housed in a casing, is rigidly attached at the front of the vehicle and positioned to target any vehicle/object directly ahead. A power supply 30 , typically the vehicle 12 volt DC, is preferably drawn from the vehicle's electrical system and regulated to operate the sensor 15 .
The accelerometer 20 may be any well-known and commercially available unit which is equipped with appropriate multi-axis measurement capability. The accelerometer 20 must be capable of detecting vehicle acceleration (or deceleration) in both the horizontal and vertical planes (i.e. the X-, Y-, and Z-axes). A preferred accelerometer 20 is the Model CXLO4M3 unit commercially available from Crossbow Technology, Inc., although any standard accelerometer capable of measurement along three axes of movement would suffice. Analog Devices' Model ADXL202 is another example of an accelerometer capable of achieving sufficient accuracy at low cost. The accelerometer 20 , typically possessing either a plastic or an aluminum casing, is rigidly attached to the frame of the vehicle. A power supply 30 , typically less than 12 volts, is preferably drawn from the vehicle's electrical system to operate the accelerometer 20 .
An electrical connection 24 carries the analog third signal (acceleration along the X-axis) from the accelerometer 20 to the data acquisition module 40 . Parallel electrical connections 26 , 28 carry the fourth (acceleration along the Y-axis) and fifth (acceleration along the Z-axis) analog signals, respectively, between the two devices. In accordance with the preferred embodiment, the data acquisition module 40 may be a commercially available unit manufactured by B&B Electronics as part number 2320PSDA. This particular optically isolated serial data acquisition module 40 provides two digital I/O lines and six A/D input channels. Of the six input channels, four possess signal conditioning circuitry. It can be readily mounted anywhere in the vehicle to provide convenient access for the wiring of the sensors 15 , 25 and accelerometer 20 , or any other analog input circuitry.
The Hall effect sensor 25 may be any well-known and commercially available unit which is equipped with appropriate measurement capability. The sensor 25 must be capable of determining the rotational velocity of an object positioned proximate the sensor 25 . A preferred sensor 25 may be the Hall effect sensor commercially available from B&B Electronics as part number HE6150, although any standard sensor capable of appropriate rotational velocity measurement would suffice. The hall effect sensor 25 includes an electronic pickup and remote magnetic sensors attached by wires to the electronic pickup. The Magnetic sensors are deployed proximate the rotating lobes of the vehicle's main drive shaft universal joint in order to determine the vehicle's speed. A power supply 30 , typically less than 12 volts, is preferably drawn from the vehicle's electrical system to operate the electronic pickup of the hall effect sensor 25 .
The direct electrical connection 45 to the vehicle's brake light is included to provide the data acquisition module with an indication that the operator's foot has made contact with the brake pedal and initiated a braking event.
The present invention requires that an event date/time and vehicle position record be made simultaneous to any braking event record. A particularly preferred global positioning receiver 50 is commercially available from Mitel Semiconductor as part number GP2000. This particular global positioning receiver component has been used to build a variety of commercially available, hand held Global Positioning System (GPS) products, and is well suited for incorporation with a processor and peripherals for storage within one housing. For purposes of the present invention, the housing may be mounted on the vehicle in a location convenient for servicing the system and for making the required connection to retrieve unified data records. It should be readily apparent to one of ordinary skill in the relevant art that if position data is not needed in a given embodiment, the global positioning receiver 50 can be replaced with an electronic timepiece that provides only a time data record to processor 60 . Further, various embodiments of processor 60 already employ a time clock that can provide a time reference to processor 60 .
With further reference to FIG. 1, a serial data connection 42 carries the unified data record, which reflects the analog signals from the sensors 15 , 25 and the analog first, second, and third signals from the accelerometer 20 , and any other analog safety data signals herein contemplated, from the data acquisition module 40 to the processor 60 . Likewise, a serial data connection 52 carries the unified data record reflecting the position and date/time signals from the global positioning receiver 50 to the processor 60 .
In accordance with the preferred embodiment, a suitable processor 60 is the commercially available unit manufactured by Toshiba as part number TMPR3922U. This CPU application is based on Toshiba's TX39 MIPS RISC processor core, and is designed for compact applications such as personal digital assistants and interactive communication devices. An alternative processor 60 is the commercially available unit manufactured by Adastra Systems as part number P-586, which is a self-contained embedded system based on an Intel Pentium-class microprocessor. Both of the illustrative processors are capable of polling the data acquisition module 40 through a data connection 44 , and the global positioning receiver 50 through a data connection 54 , at discrete time intervals or at the occurrence of a discrete event. In either case, the processor 60 may be contained in the same housing as the global positioning receiver 50 , is supported by all standard and necessary peripheral components including RAM memory, and is powered from the vehicle's electrical distribution system.
The processor 60 is controlled by resident software written to identify and record braking events. Parameters (e.g. vehicle speed, following distance to vehicle immediately ahead) for braking events based on vehicle type and/or weight, as established by authorized safety personnel, are resident in the software. The software facilitates the generation of polling events whenever one or more of the parameters is exceeded, polls the various analog and digital inputs at specified time intervals as long as a parameter remains in an exceeded condition, and compiles the resulting unified data records for storage or instantaneous monitoring/recording. The software may comprise a sequence of well known and commercially available real time control modules preferably authored in the C++ programming language, and compiled with a commercially available compiler that is compatible with the processor class employed and specially tailored for embedded systems. Once the processor 60 has polled the various sensor 15 , 25 and accelerometer 20 data inputs, the processor 60 compiles a unified data record in one of many known standardized formats for storage in storage means 70 . In the preferred embodiment, the storage means 70 is commercially available digital memory such as DRAM or SDRAM. It should be readily apparent to one of ordinary skill that commercially available flash memory, magnetic disc memory, or optical memory can be employed as the storage means 70 . Flash memory has the added advantage that it comes in the form of cards that are compact and easy to transport to a remote computer for analysis. Furthermore, they do not require a continuous power supply to retain data.
Moreover, it should be readily apparent to one of ordinary skill in the art of the present invention that the retrieval of the unified data records from the storage means 70 need not be accomplished by a physical connection between the processor 60 and the storage means 70 . The retrieval of the unified data records can be easily accomplished by the incorporation of IP modem technology communicating with the processor 60 and digital cellular communications to relay data from the IP modem of the vehicle system to an IP modem at a remote location, in conjunction with the storage means 70 at the remote location. Satellite telecommunication services can also be used in place of digital cellular communication services.
Exemplary programming and use of a preferred embodiment of the brake response and following distance monitoring and safety data accounting system 10 is as follows:
Vehicle speed is sensed and calculated by the Hall effect sensor 25 which is continuously polled by the processor 60 . A series of data records are generated indicating the amount of time, calculated to thousandths of a second, that the vehicle spends in any one of a predetermined series of speed ranges. Specifically, the ranges are >0-10 mph, >10-20 mph, >20-30 mph, >30-40 mph, >40-50 mph, >50-60 mph, >60-70 mph, and >70-80 mph. Higher speed rangs may be included if required. Individual data records are generated for each of the ranges, as the vehicle accelerates or decelerates, indicating the amount of time the vehicle's speed remains within that 10 mph interval.
Concurrent with the compilation of the above data records, the processor 60 continuously monitors input from the proximity sensor 15 and records, at 0.25 second intervals, the distance (in feet) from the sensor 15 (i.e. front end of the vehicle being operated/monitored) to the rear end of the vehicle, or any other object, immediately ahead. Others skilled in the art will realize that distances may be measured in units other than feet (e.g. meters) and that the time interval may be more or less than 0.25 seconds. This information is compiled with the corresponding vehicle speed data record to calculate and record, among others, average values for following distance (i.e. sum of distance measurements divided by number of measurements) within each of the above listed 10 mph speed ranges.
Data records are compiled, within the resident software, over a user-definable period as follows: All like data records (e.g. >0-10 mph, >10-20 mph, >20-30 mph, etc.) are grouped and a statistical analysis is performed to determine a weighted average for following distance in each speed range. Further statistical analysis is performed to buffer outlying data due to anomalous conditions (e.g. lane changes, non-moving/stationary objects, turns, etc.). The software also generates a single weighted average for all ranges that may be used as a driver evaluation tool. Raw data records may either be saved for later investigation (e.g. route characteristics, accident reconstruction, other significant events) or can be purged at the end of the period.
Concurrent with the compilation of the above described data records, the present invention continuously monitors the distance measurement provided by the proximity sensor 15 , at each 0.25 second interval, for negative changes in that distance, defined as a closing velocity event (CV). If, during any 0.25 second interval, the preset value for a specified parameter (see the “Negative change in following distance” column in the table below) associated with the applicable 10-mph speed range is equaled or exceeded and the distance between the front end of the monitored vehicle and the back end of the leading vehicle satisfies a second specified parameter (see the “When following distance is” column of the table), a CV is deemed to have occurred and the system 10 is prompted to record the time of the CV's occurrence. Input from the direct electrical connection 45 to the vehicle's brake light will then be polled for time of activation (i.e. the operator's application of the brakes). Recommended values, for each 10 mph speed range, for the negative change in following distance and following distance parameters are outlined in the table below:
Negative change in
When following
Speed Range
following distance
distance is:
>0-10 mph
0.75 ft.
<15 ft.
>10-20 mph
1.15 ft.
<25 ft.
>20-30 mph
1.40 ft.
<35 ft.
>30-40 mph
1.70 ft.
<45 ft.
>40-50 mph
2.00 ft.
<55 ft.
>50-60 mph
2.25 ft.
<65 ft.
>60-70 mph
2.25 ft.
<75 ft.
>70-80 mph
2.25 ft.
<85 ft.
The preset values may be altered to suit the needs of any specified driving circumstance (e.g. city versus highway driving conditions). GPS data coupled with appropriate software may also be used to automatically alter preset values.
The system 10 may then compute the difference between the time of the CV and the time of brake activation by the operator to compile a data record reflecting brake response times for each speed range. Data records are compiled, within the resident software, over a user-definable period as follows: All like data records are grouped and a statistical analysis is performed to determine a weighted average for operator brake response time in each speed range. Further statistical analysis is performed to buffer outlying data due to anomalous conditions. The software also generates a single weighted average for all ranges that may be used as a driver evaluation tool.
Concurrent with the compilation of the above data records, when a CV occurs the processor 60 may continuously monitor input from the accelerometer 20 to determine the exact time that deceleration begins, which indicates the moment when the operator's foot is removed from the gas pedal. This data record can be compared with the time that the brake pedal is actually applied for each CV. Also, a data record may compiled which measures the intensity and duration of each braking event, via the deceleration measured by the accelerometer 20
FIG. 2 is a schematic diagram of the functionality of the electronic data portions of the brake response and following distance monitoring and safety data accounting system 10 according to a preferred embodiment of the present invention. Analog inputs 100 such as following distance, vehicle speed, and the X-, Y-, and Z-axis components of vehicle acceleration are processed by the data acquisition module 40 into digital inputs 200 . Additional inputs 210 , such as those from the GPS unit 50 (e.g. vehicle position, date/time records), may already be in a compatible digital form for processing. The processor 60 compiles a unified data record 300 which contains fields for each of the desired data in the record, at least including (1) following distance, (2) vehicle speed, (3) X-axis acceleration, (4) Y-axis acceleration, (5) Z-axis acceleration, (6) GPS coordinate data for vehicle position, and (7) date/time information. The foregoing information is stored as a unified data record for later retrieval. The record can be queried for patterns of inappropriate braking or brake response due to maintaining inappropriate following distances. Specific events and pattern data can be compared to baseline parameters to ensure that a given driver follows proper guidelines such as: (1) employing sensible driving tactics based on existing road conditions (i.e. parameters for good versus inclement weather conditions would vary), (2) employing sensible driving tactics based on existing road design (i.e. curving/winding roads, or uphill/downhill sections where the posted speed limit is incompatible with driving in good/excellent weather conditions), (3) avoiding excessive brake system wear, and (4) generally operating the vehicle in a safe manner.
The above-described system accurately and consistently measures and records the brake response time and average following distance for the operators of vehicles, and especially private/commercial vehicles and heavy equipment. The system also measures other safety-related information in such vehicles, organizes the data retrieved from the various sources herein described into a usable and consistent record, which can then be compiled with like records to analyze brake response time, following distance, and other safety parameters in a comprehensive and statistical manner. The data can be used to monitor compliance with safety policies and guidelines for vehicle operation in order to reduce insurance and other expenses caused by injuries to employees, employers of truck drivers or large commercial equipment operators.
Having now fully set forth the preferred embodiments and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept. It is to be understood, therefore, that the invention may be practiced otherwise than as specifically set forth herein. | An improved brake response time and following distance monitoring and safety data accounting system for motor vehicles and other types of human-operated equipment is herein disclosed. The present invention measures and records events where preset parameters are exceeded. Specifically, the present invention measures and records, among others, parameters associated with instantaneous vehicular following distance, average vehicular following distance, instantaneous changes in following distance, and brake response time of an operator. The system is equipped with data processing and communication means allowing an employer, a parent, an insurance carrier, or any other interested person to verify that the vehicle in question is operated in an appropriate manner. The present invention records each vehicle braking cycle to determine if previously established safe operating parameters were maintained while noting the date, time of day, and location of the incident. The information retrieved is compiled in a data record and stored in a storage system for instantaneous use or retrieval when desired. | 1 |
CROSS-REFERENCE TO PRIOR APPLICATION
This application claims the benefit under 35 USC 119(e) of provisional application serial No. 60/187,963 filed Mar. 9, 2000.
BACKGROUND OF THE INVENTION
The present invention relates to glass fiber mats and a process for their production.
Glass fiber mats are composed of glass fibers held together by a binder material. These mats are commonly used in the production of asphalt-containing roofing shingles. A problem with current glass mat manufacturing technology is that the glass mats exhibit a poor balance of tensile strength and tear strength. Although it is known how to increase either tear or tensile strength individually, a formulation or process change made to increase one of these properties will simultaneously decrease the other. Commercial manufacturers of glass fiber mats have long felt a need to have a glass fiber mat in which this balance of properties is improved.
U.S. Pat. No. 4,430,158 (Jackey et al.) discloses a method of preparing a glass fiber mat having improved wet tensile strength by using a binder composition containing a urea formaldehyde resin and 0.01-5 percent of a water-soluble, anionic surfactant, said surfactant having a hydrophobic segment of 8-30 carbon atoms and an anionic segment selected from among carboxy, sulfate ester, phosphate ester, sulfonic acid and phosphonic acid groups. Jackey states that using his binder in an amine oxide white water system gives glass mats that retain up to 79 percent of their dry tensile strength under wet conditions.
U.S. Pat. No. 4,917,764 (Lalwani et al.) discloses that glass fiber mats having improved strength and fiber wetability can be prepared by incorporating 1-6 percent of certain carboxylated styrene butadiene latexes into a urea formaldehyde resin solution and using that solution as a binder.
U.S. Pat. No. 5,518,586 (Mirous) discloses preparation of glass mats using a binder comprising a urea formaldehyde resin plus a water-insoluble anionic phosphate ester in a hydroxyethyl cellulose white water system. Mirous states that Jackey's system gives no improvement in tear strength. Mirous also states that when glass fibers are dispersed in white water containing a polyacrylamide viscosity modifier, high mat tear strengths have been achieved with latex fortification of urea formaldehyde resins.
As a matter of commercial reality, despite the wealth of information in the prior art, glass mat manufacturers desire an affordable binder system that would give increased tear strength and a good balance of tear strength and tensile strength. Current commercially available binder systems do not meet these criteria; they provide satisfactory tear or tensile strength, but not both.
SUMMARY OF THE INVENTION
This invention relates to a method for improving the balance of tensile strength and tear strength of cured, latex-modified urea formaldehyde (UF) resin-bound glass fiber nonwoven mats. The invention is also directed to the glass fiber nonwoven mats produced by the method, and to the binder composition used in the method. The mats are useful in, for example, the manufacture of roofing shingles.
In one aspect the invention is a process for preparing a glass fiber mat, the process comprising: (a) forming a wet glass fiber mat; (b) applying to the wet glass fiber mat a binding amount of a binder comprising: a urea formaldehyde resin, 0.5-15% by weight of a latex, based on the dry weight of the urea formaldehyde resin and the latex, and 0.5-15% by weight, based on the dry weight of the latex solids, of a salt or free acid of an anionic organic phosphate ester surfactant; and (c) curing the binder.
The invention also includes a binder composition comprising a urea formaldehyde resin and 0.5-15% of an emulsion polymer, based on the dry weight of the urea formaldehyde resin and the emulsion polymer, and 0.5-15%, based on the dry weight of the emulsion polymer solids, of a salt or free acid of an anionic organic phosphate ester surfactant. In another aspect, the invention includes a binder composition comprising: (a) a urea formaldehyde resin; (b) 0.5-15% by weight of an emulsion polymer, based on the dry weight of the urea formaldehyde resin and the emulsion polymer, the emulsion polymer containing phosphorus in its polymer molecule as 0.1 to 10% by weight of the polymerized residue of an anionic phosphate group-containing monomer, or from 0.1 to 2 weight percent of the polymerized residue of a perphosphate initiator, or a combination of these, based on the solids of the emulsion polymer; and (c) optionally 0.5-15% by weight, based on the dry weight of the emulsion polymer solids, of a salt or free acid of an organic phosphate ester surfactant. The mat produced using the binder of the invention is also part of the invention.
The present invention enables production of a glass fiber nonwoven mat with a surprisingly improved balance of dry tensile strength and tear strength.
DETAILED DESCRIPTION OF THE INVENTION
The method of the invention employs a binder and glass fibers.
The binder of the invention comprises a UF resin, an emulsion polymer, and a molecule containing a phosphate moiety. The emulsion polymer may also be the molecule containing the phosphate moiety. The molecule containing a phosphate moiety can be incorporated into the binder in several ways. For example, it can be in the aqueous emulsion polymer in the form of a surfactant that is in the reaction mixture when the emulsion polymer is prepared, or it can be in the form of a reactive surfactant that is in the reaction mixture when the emulsion polymer is prepared, or it can be in the form of a perphosphate initiator used when the emulsion polymer is prepared, or it can be added as a surfactant during the formulation of the UF resin, the emulsion polymer or the binder. The phosphate moiety-containing molecule can be incorporated into the binder using any combination of these techniques. For example, the binder may comprise both a surfactant and an emulsion polymer prepared using at least one phosphate group-containing surfactant monomer or perphosphate initiator.
Urea formaldehyde resins are well known and widely commercially available. Examples of commercially available urea formaldehyde resins include CASCO-RESIN C-802B and CASCO-RESIN 520HT, which are available from Borden, Inc. Mixtures of UF resins can be employed. The UF resin is employed in an amount sufficient to provide structural integrity both to the glass mat during processing into a shingle and to the shingle itself. The UF resin suitably is from about 85 to 99.5 weight percent of the binder, based on the dry weight of the UF resin and emulsion polymer in the binder, preferably is from about 88 to about 95 weight percent of the binder, and most preferably is from about 89 to about 93 weight percent of the binder.
Emulsion polymers, such as carboxylated styrene butadiene latexes, are well known and widely commercially available. The emulsion polymers employed in the present invention are copolymers prepared from emulsion polymerization of a monomer mixture comprising at least one of the following: styrene or one or more substituted styrenes; a diene such as butadiene or one or more substituted dienes; vinyl esters such as vinyl propionate, vinyl acetate and isopropenyl acetate; (meth)acrylic esters such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and methyl methacrylate; vinyl chloride; acrylonitrile or methacrylonitrile; and the like. Also included are functional monomers such as ethylenically unsaturated carboxylic acid monomers, for example, acrylic acid, methacrylic acid, itaconic acid, fumaric acid and the like; and acrylamide or substituted acrylamides. Copolymers of styrene, butadiene, and a carboxylic acid monomer, optionally including-a phosphate-group-containing surfactant monomer, are preferred. Methods of preparing emulsion polymers are well-known to those skilled in the art. Mixtures of emulsion polymers can be employed.
In one embodiment of the invention, the monomer mixture can include a phosphate group-containing polymerizable surfactant monomer such as, for example the phosphate ester of 2-hydroxyethyl methacrylate, which is commercially available as T MULZ 1228 from Harcros Chemicals Inc. In another embodiment of the invention, a perphosphate initiator is employed to prepare the emulsion polymer. When a phosphate group-containing monomer, or perphosphate initiator, or a combination of these, is employed in the preparation of the polymer, it is employed in an amount sufficient to improve the balance of tear strength and tensile strength of a bonded nonwoven glass mat prepared using an emulsion polymer that was polymerized using the phosphate monomer, the perphosphate initiator, or a combination of these, as compared to the balance of tear strength and tensile strength of a bonded nonwoven mat prepared without using the phosphate monomer or the perphosphate initiator. Preferably, the amount of phosphate-containing monomer employed is from about 0.1 to about 10 weight percent, based on the dry weight of the emulsion polymer employed in the binder. More preferably, the amount of phosphate-containing monomer employed is from about 0.5 to about 7.5 weight percent, and most preferably is from about 1 to about 5 weight percent. The amount of perphosphate initiator employed is preferably from about 0.1 to about 2 weight percent, based on the dry weight of the emulsion polymer employed in the binder. More preferably, the amount of perphosphate initiator employed is from about 0.2 to about 1.5 weight percent, and most preferably is from about 0.5 to about 1 weight percent.
The emulsion polymer is employed in an amount sufficient to enhance binder processability and sufficient to enhance the properties of the bonded nonwoven glass mat as described above. Preferably, the amount of emulsion polymer employed is from about 0.5 to about 15 weight percent based on the dry weight of the urea formaldehyde resin and emulsion polymer. More preferably, the amount of emulsion polymer employed is from about 5 to about 12 weight percent, and most preferably is from about 7 to about 11 weight percent.
An organic, anionic, phosphate ester surfactant is employed in certain embodiments of the invention. The surfactant suitably is a salt or free acid of an anionic organic phosphate ester. If the free acid is employed, it can be solubilized in water as a salt. Many examples of these surfactants are commercially available. Examples of commercially available anionic phosphate ester surfactants include RHODAFAC RE-610 and RHODAFAC BX-660, which are available from Rhone Poulenc. Water-soluble surfactants are preferred. The hydrophobe of the surfactant can be aliphatic or aromatic, with aliphatic being preferred. A preferred surfactant has a polyethyleneoxy segment of from about 3 to about 15 ethyleneoxy units, and more preferably from 4 to 12 units, and most preferably from 5 to 10 units. Mixtures of surfactants can be employed.
The surfactant is employed in an amount sufficient to improve the balance of tear strength and tensile strength of a bonded nonwoven glass mat prepared using the surfactant, as compared to the balance of tear strength and tensile strength of a bonded nonwoven prepared without using the surfactant. Preferably, the amount of surfactant employed is from about 0.5 to about 15 weight percent, based on the dry weight of the emulsion polymer employed in the binder. More preferably, the amount of surfactant employed is from about 0.75 to about 10 weight percent, and most preferably is from about 1 to about 5 weight percent.
It is possible to employ any combination of phosphate group-containing monomer, perphosphate initiator, and anionic organic phosphate ester surfactant. When a phosphate group-containing monomer or perphosphate initiator is employed in the preparation of the polymer, the use of a phosphate ester surfactant is optional. When a phosphate group-containing monomer or perphosphate initiator is not employed in the preparation of the polymer, the phosphate ester surfactant is required. When a combination of these materials are employed, the components are employed in amounts sufficient to achieve the desired improved balance of tear and tensile strength.
The binder is prepared by mixing its components using well-known mixing techniques such that a homogeneous binder is employed. The order of blending of the components is not critical. The components of the binder may be individually premixed in any order and in any combination. For example, the phosphate ester surfactant may be post-added to the emulsion polymer or to the UF resin. In addition, the phosphate ester surfactant can be added during the polymerization of the emulsion polymer to stabilize the polymer particles.
The binder may also contain conventional additives such as, for example, pigments, fillers, anti-migration aids, curing agents, neutralizers, coalescents, wetting agents, biocides, plasticizers, organosilanes, anti-foaming agents, colorants, waxes and anti-oxidants. The binder may be applied to a glass fiber nonwoven by conventional techniques such as, for example, air or airless spraying, padding, saturating, roll coating, curtain coating, beater deposition, coagulation and the like. The amount of binder employed in the preparation of a bonded glass fiber mat is from 10-35% LOI (loss on ignition). Preferably, the amount of binder is from about 15 to about 25% LOI, and most preferably is from about 18 to about 22%.
Procedures for preparing glass fiber nonwoven mats, and the fibers used in the preparation process, are well known to those skilled in the art. Glass fiber shingle mat is commercially available from several manufacturers. The glass fiber nonwoven mat may be prepared from fibers of various length which may have been previously subjected to various treatment or primer steps. The glass fiber nonwoven can be of various thicknesses as appropriate for the desired end use and can be formed by a wet laid or dry laid process. The glass fiber nonwoven may contain fibers other than glass, for example aramid fibers, ceramic fibers, metal fibers, carbon fibers, polyimide fibers, polyester fibers and rayon fibers, in so far as they do not adversely affect the performance of the nonwoven mat.
The aqueous binder, after it is applied to a glass fiber nonwoven mat, is heated to effect drying and curing. Heat treatment at about 120° C. to about 400° C. for a period of time of from about 3 seconds to about 15 minutes may be carried out; treatment at about 150° C. to about 200° C. is preferred. The drying and curing functions may be effected in two or more distinct steps, if desired.
The cured glass fiber nonwoven mats may be used for applications such as, for example, roofing mats, insulation batts or rolls, reinforcing mat for flooring applications, roving, microglass-based substrate for printed circuit boards or battery separators, filter stock, tape stock, and reinforcement scrim in cementitious and non-cementitious coatings for masonry.
The present invention provides a glass fiber nonwoven mat with a surprisingly improved balance of dry tensile strength and tear strength relative to a glass fiber nonwoven mat that is prepared using a control binder, not of the invention.
Specific Embodiments of the Invention
The following examples and comparative experiments are given to illustrate the invention and should not be construed as limiting its scope. All parts and percentages are by weight unless otherwise indicated.
Glass Mat Preparation Procedure
This procedure is employed to prepare the mats used in the examples that follow. Glass fiber nonwoven handsheets are prepared with Owens Corning 9501, ¾ inch length, sized glass chop using approximately 6.4 grams of glass fiber per sheet (2.0 pounds per 100 square feet). The glass fiber is dispersed in water using MAGNIFLOC 1885A (American Cyanamid Company), an anionic polyacrylamide water-in-oil emulsion, and RHODAMEEN VP-532 SPB dispersant(Rhone-Poulenc Chemical Company). Handsheets are formed in a Williams handsheet mold. The wet sheet is transferred to a vacuum station and de-watered. An aqueous admixture with a UF/latex blend weight ratio of 9:1, at 20% solids, i.e. 9 weight parts UF resin solids per 1 part latex solids in 40 parts of water, is prepared and applied to the de-watered sheet and the excess is vacuumed off. The sheets are dried/cured in a forced air oven for 3 minutes at 205° C. The binder amount on the samples is 20% LOI.
All tensile values are in lbs/in. Wet tensiles are run after soaking the samples for 10 minutes in 82° C water. Samples are 2″ by 5″; gap space is 2 inches; crosshead speed is 2 inches/minute.
Elmendorf tear strength is determined on 2.4375 inch by 3 inch samples. A single-ply sample is placed in a Thwing-Albert Tear Tester with a 1600 g tear arm. The sample is notched with a 0.75 inch cut and the arm is released. Tear strength is recorded in grams/ply.
EXAMPLE 1
Non-carboxylated S/B Latex DL460NA 1
Binder
Binder Composition
1
100% CASCO-RESIN 2 C-802B
2
90/10 Mixture of CASCO-RESIN 2 C-802B and Latex
DL460NA 1
3
90/10 Mixture of CASCO-RESIN 2 C-802B and Latex
DL460NA 1 ; 10% RHODAFAC 3 BX-660 Phosphate
Ester Surfactant Post-Added to Binder Mix (Active,
by Weight based on latex solids)
4
90/10 Mixture of CASCO-RESIN 2 802B and Latex DL460NA 1 ;
5% (Active, by Weight) RHODAFAC 3 BX-660 Phosphate Ester
Surfactant Post-Added to Binder Mix
Tensile
Wet/Hot Tensile
%
Tear Strength
Binder
(lbs./inch)
(lbs/inch)
Retention
(g/ply)
1*
45
31.5
70
637
2*
62.5
30
48
493
3
51.5
37.5
73
821
4
61.5
49
80
676
*Not an embodiment of the invention.
The four binders in Example 1 demonstrate the unexpected improvement in performance achieved through the addition of a phosphate ester surfactant. Blending latex with UF resin (compare Binders 1 and 2) improves dry tensile but hurts tear strength. The addition of 5 or 10% phosphate ester surfactant to Binder 2 (compare Binders 2, 3 and 4) gives an improved balance of tensile and tear strength, i.e., a dry tensile strength of greater than 50 lb./inch and a tear strength of greater than 500 g/ply.
EXAMPLE 2
Carboxylated S/B Latex CP615NA 1
Binder
Binder Composition
5
90/10 Mixture of CASCO-RESIN 2 C-802B and Latex
CP615NA 1
6
90/10 Mixture of CASCO-RESIN 2 C-802B and Latex
CP615NA 1 ; 5% (Active, by Weight) RHODAFAC 3 RS410
Phosphate Ester Surfactant Post-Added to Binder Mix
7
90/10 Mixture of CASCO-RESIN 2 C-802B and Latex
CP615NA 1 ; 5% (Active, by Weight) RHODAFAC 3 RS610
Phosphate Ester Surfactant Post-Added to Binder Mix
8
90/10 Mixture of CASCO-RESIN 2 C-802B and Latex
CP615NA 1 ; 5% (Active, by Weight) RHODAFAC 3 RS710
Phosphate Ester Surfactant Post-Added to Binder Mix
9
90/10 Mixture of CASCO-RESIN 2 C-802B and Latex
CP615NA 1 ; 5% (Active, by Weight) RHODAFAC 3 BX-660
Phosphate Ester Surfactant Post-Added to Binder Mix
Tensile
Wet/Hot Tensile
%
Tear Strength
Binder
(lbs./inch)
(lbs./inch)
Retention
(g/ply)
5*
83
57.5
69
461
6
68
43.5
64
525
7
69.5
48.5
70
599
8
74.5
46.5
62
529
9
72.5
55.5
77
575
*Not an embodiment of the invention.
The five binders in Example 2 demonstrate the unexpected improvement in performance achieved through the addition of a variety of phosphate ester surfactants to a UF/latex binder mix. RHODAFAC RS410, 610 and 710 are aliphatic phosphate esters that differ in the number of polyethyleneoxy units in the hydrophile. The hydrophobe in RHODAFAC BX-G660 is octylphenol. The hinders containing these phosphate ester surfactants demonstrate an improved balance of glass mat tensile and tear strength when compared to the properties obtained using a simple blend of UF resin and latex (Binder 5).
EXAMPLE 3
Non-carboxylated S/B Latex DL460NA 1 and Carboxylated S/B Latex DL490NA
Binder
Binder Composition
10
100% CASCO-RESIN 2 520HT
11
90/10 Mixture of CASCO-RESIN 2 520HT and Latex
DL490NA 1
12
90/10 Mixture of CASCO-RESIN 2 520HT and Latex
DL460NA 1 ; 10% (Active, by Weight) RHODAFAC 3 BX-660
Phosphate Ester Surfactant Post-Added to Binder Mix
Tensile
Wet/Hot Tensile
%
Tear Strength
Binder
(lbs./inch)
(lbs./inch)
Retention
(g/ply)
10*
42.5
28.5
67
536
11*
81.5
58.5
72
415
12
55.5
46
83
676
*Not an embodiment of the invention.
The binders described in Example 3 demonstrate the effect if adding a latex to a high-tear UF resin (compare Binders 10 and 11). Tensile improves markedly with the addition of 10% latex but tear strength is diminished. Addition of a phosphate ester surfactant to a high-tear UF resin/latex binder mix improves both tensile and tear strength (compare Binders 10 and 12).
EXAMPLE 4
Carboxylated S/B Latex CP615NA 1 Made With 2% Phosphate Ester Monomer
Binder
Binder Composition
13
90/10 Mixture of CASCO-RESIN 2 FG486 and Latex
DL490NA 1
14
90/10 Mixture of CASCO-RESIN 2 FG486 and Latex
CP615 1 -type made with 2 parts T MULZ 1228 4
Tensile
Wet/Hot Tensile
%
Tear Strength
Binder
(lbs./inch)
(lbs/inch)
Retention
(g/ply)
13*
47.5
30
63
413
1 4
61
32
52
549
*Not an embodiment of the invention.
In Example 4, 2 parts of styrene monomer in carboxylated S/B Latex CP615 have been replaced with 2 parts of T MULZ 1228, the phosphate ester of 2-hydroxyethyl methacrylate. No phosphate ester surfactant is employed in the polymerization. The balance of glass mat tensile and tear strength properties is markedly and unexpectedly improved with the use of a phosphated monomer-containing latex compared to the use of a latex without the phosphate group-containing monomer.
1. Available from The Dow Chemical Company.
2. Available from Borden.
3. Available from Rhone-Poulenc.
4. Available from Harcros Chemicals Inc. | A method for improving the balance of tensile strength and tear strength of cured urea formaldehyde (UF) resin-bound glass fiber nonwoven mats; the glass fiber nonwoven mats produced by the method, and a phosphate-containing binder composition useful in the method. The mats are useful in, for example, the manufacture of roofing shingles. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns a pressurized can, the body of which is a cylinder, with a preferably pushed-in bottom, a dome-like top section with a valve to expel the can contents consisting of product component and propellant, and which has a floating plunger mounted on the interior wall of the cylinder, which separates the propellant gas chamber from the product component and which has a cavity in its upper side. The pressurized can is particularly suited for the expulsion of building foams, for instance single-component polyurethane foams, such as those commonly used for construction and sealing purposes.
2. Description of the Related Art
Such pressurized cans are used to expel different products. These include sealants on a rubber, oil, butyl, silicon and acrylate basis, but especially foaming agents based on polyisocyanate prepolymers. On contact with water (humidity), such polyisocyanate prepolymers turn into polyurethane foams which are used for sealing, filling, insulation, adhesion and fastening, especially in the construction industry. The pressurized cans to expel such foaming agents on a polyisocyanate basis are usually made of sheet steel, because of the great interior pressure among other reasons, and special valves are used to facilitate the handling of the can contents.
Pressurized cans of this type are known, for instance, from U.S. Pat. No. 3,362,589. When used for the production of polyurethane foams, such pressurized cans contain a filling consisting of, for example, 60% by weight polyurethane prepolymers, and about 40% by weight propellant gas. The greater part of the propellant gas is used as a transporting agent, to expel the prepolymer from the pressurized can. Only a small portion of the propellant gas, about 10%, turns into a foaming agent and supports expansion.
If the can is stored for a longer period of time, the component substances usually separate, in which case the specifically heavier propellant settles on the bottom of the pressurized can. Before use, it is advisable to shake the can forcefully and for a long time to achieve the intensive mixture of foaming agent and propellant. Insofar as the gas works as a propellant and comes out of the pressurized can with the foaming agent, it escapes into the atmosphere under expansion.
EP-A 0 078 936 describes a pressurized can for the expulsion of building foams, the body of which is a cylinder, with a preferably pushed-in bottom and a dome-like top section with a seal. A valve for expelling the can contents consisting of a propellant and foaming agent is placed in the dome-like top section. A floating plunger is mounted on the interior wall of the body cylinder between the propellant and the foaming agent contained in different chambers of the can which separates the lower propellant gas chamber from the chamber above it which contains the foaming agent. As the can empties, the plunger moves up within the can, stopping against the dome-like top section of the pressurized can when finally empty. To ensure thorough emptying, the top of the plunger is shaped to fit the curvature of the can dome, and has a cavity in the area where the valve disk reaches down into the inside of the can. According to EP-A 0 078 936, the plunger is fitted into the can cylinder in such a way that propellant can pass between the wall of the can and the pressurized can from the propellant chamber into the foaming agent chamber, but the foaming agent essentially remains in its upper chamber.
Pressurized cans of the type described in EP-A 0 078 936 have proven themselves very well in practice. They make it possible to use up the foaming agent to a great extent, so that only very small quantities of foaming agent remain when the can is fully empty. These small quantities fall within the range of about 5% of the original can contents. The disadvantage, however, is that the polyisocyanate prepolymers used as foaming agent[s] are highly reactive and toxic. For this reason, even empty pressurized cans cannot be disposed of easily, but require special handling pursuant to the regulations applicable to such residues. This leads to considerable drawbacks and costs. The same applies to a number of other products which are sold in cans and which are highly reactive and/or toxic.
SUMMARY OF THE INVENTION
The goal of the invention, therefore, is to produce a pressurized can in which the product components remaining after use and when the can is basically empty, in particular polyisocyanate prepolymers, can be converted into environmentally harmless or tolerable byproducts. The conversion should automatically occur when the pressurized can has already yielded the expellable portion of its contents.
This goal is met with a pressurized can of the type described in the beginning, in which the cavity contains a component reactive with the product component that is sealed off from the product component. A trigger device is placed in the interior of the dome-like top section, which breaks the seal when the plunger reaches a position immediately below the dome-like top section or strikes up against it.
Under the invention, therefore, the trigger device installed in the dome-like top section breaks the seal when the floating plunger installed in the pressurized can strikes up against it, such that the reactive component, hermetically sealed off in the cavity from the product component until the moment of detonation or penetration is released and caused to react with the product component. This reaction converts the product component into harmless byproducts which may be disposed of easily. It is especially advantageous that the conversion occurs automatically when the pressurized can has yielded the expellable portion of its contents, containing only the remaining and not expellable residual contents. The reactive component is released automatically without any action by the person using the can.
To suit the desired purpose, the trigger device should preferably be a spike, mounted, for example, on the underside of the valve disk. The cavity in the upper side of the plunger is designed so that it can interact with the trigger device, in particular the spike. If the spike is placed on the underside of the valve disk, a cavity in the center of the top side of the plunger would suit the purpose.
The seal protecting the cavity against the product component can be made of any material and can take any form, as long as the interaction with the trigger device leads it to be opened or broken. It would suit the purposes for the seal to be a foil, made of, for example, polyethylene, polypropylene or aluminum. Other suitable materials can be used for such foils. It must be kept in mind that if the reactive component is a low-molecular substance, like water, for example, polyethylene and polypropylene cannot ensure a complete seal, since water diffuses through these substances. In this case, it would suit the purposes to use an aluminum foil. If the plunger is not made out of metal, but out of polyethylene or polypropylene, the cavity should be lined with an aluminum foil, especially if water is to be used as the reactive component, in which case the sealing foil should be connected to the lining foil in the form of a pouch or can.
The reactive component contained in the cavity in the top of the plunger should be available in such a quantity to ensure that the volume product component remaining in the pressurized can after the plunger strikes up against the dome-like top section can be fully converted into environmentally and/or toxicologically harmless byproducts. The quantities required for this purpose are quite small, and lie in the range of 0.5 to 1 gram of water for a pressurized can for the production of polyurethane foam made from polyisocyanates, with a filling volume of 750 ml and an expulsion rate of 95%.
As reactive components for product components that harden on contact with moisture, OH-reactive substances in particular may be considered, for instance water, already mentioned, but also monovalent, low molecular weight alcohols such as ethanol, polyvalent alcohols such as ethylene glycol or propylene glycol or glycerine, or low molecular weight carbonic acids, such as ethanoic acid or propanoic acid, as well as mixtures of these substances with water and/or with each other. NH-reactive substances could also be used, preferably monovalent or polyvalent primary or secondary amines. With these substances, it is necessary to apply stoichiometric or slightly excess quantities to the residual product component, to ensure complete conversion of the product component.
Alternatively, catalytically active substances may be used as the reactive component, such as those, for instance, that initiate the polymerization of the reactive component. Such agents are, for instance, metal alkanoates, such as sodium octoate or potassium octoate. Catalytically active substances can also be used to increase the reactivity of OH-reactive substances, in the form of tertiary amines, for instance.
It is especially useful to use water and/or a polyvalent alcohol as the reactive component in the case of a commonly sold prepolymer based on isocyanates, in which case a catalytic substance such as triethylene diamine can be added to accelerate the reaction. Other known reaction accelerants may be used. But a pirk catalyzer can also be considered for the reactive component, which would bring about the radical polymerization of the remaining isocyanate, converting it into tolerable byproducts.
The pressurized cans according to the invention are filled with the usual product component and propellants. The reactive component is formed by substances which are capable of reacting with these product components, and which are chosen with the latter in mind, and which are known in themselves. The pressurized cans used for the invention are also like previous cans in terms of their form and the expulsion technique, aside from the presence of the trigger device and the special shape of the plunger with its reactive component sealed off from the interior of the can.
Details of the invention are found in the following description of a form of execution based on the attached diagrams.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows, schematically and under omission of all details which are not necessary for an understanding of the invention, a pressurized can according to the invention, partially in cross-section;
FIG. 2 shows the upper end of the pressurized can in cross-section and enlarged;
FIG. 3 shows individual illustrations a through c of the plunger used in the invention, in cross-section.
DETAILED DESCRIPTION OF THE INVENTION
The pressurized can shown in FIGS. 1 and 2, has a body marked 1, which is made of steel sheet in the illustrated execution example. The central part consists of a cylinder 2, whose lower rim at 3 is flanged with the rim 4 of a bottom 6 pushed in at 5. The upper rim 7 of the cylinder 2 runs into a dome-like top section 8, i.e. in the form of a truncated cone, the rim 9 of which top section, encircling a central opening, has a closure mechanism 11. The closure mechanism has a disk 10, whose rim 13 is wrapped around the rim 9. The disk 10 has a central opening 40, in which a plug-like rubber seal 41 of a valve 12 is set. The valve body 42 is tube-shaped and is closed at its interior end with a valve disk 43, which lies pressed against the rubber seal under the influence of the interior pressure. Under the valve disk 43 and within the tube sealed on the outside are one or several openings 44, through which the can contents escape when the valve body 42 is tilted, thus disengaging the valve disk 43. On the underside of the valve disk 43 is a spike 45, which protrudes perpendicularly into the interior chamber of the pressurized can.
A floating plunger 14 is mounted in the cylinder 2. The plunger shirting 15 runs along the cylinder wall, but the plunger has enough mobility in the can to move without sticking in the direction of can axis A. The plunger is mounted in the cylinder in such a way that propellant can pass between the plunger shirting 15 and the inner wall of the cylinder 2, from the lower can area to the upper can area. It is also possible to have a seal between the plunger shirting 15 and the inner wall of the can cylinder 2, or to set the distance between the plunger shirting and the cylinder wall in such a way that a film seal is formed in this interstice by the entry of product component.
In rest position, the plunger floats on the propellant gas filling, with the product component above it. When the valve is activated, liquid propellant gas vaporizes out of the filling, driving the plunger along with the product component upwards in the direction of the valve.
The plunger 14, thus located between propellant gas filling and product component filling, defines a variable lower length 19 of the cylinder 2. The circumference 19 of the cylinder thereby surrounds a chamber 20, which is filled with propellant and is closed at the bottom by the can base 6 and at the top by the underside 17 of the plunger 14. The propellant is filled (or injected) with the aid of a filling needle (not shown) through a radial opening 21 of a valve in the can base, and a rubber valve ring 22 placed around the valve.
The plunger 14 floats on the propellant filling of the propellant gas chamber 20; the liquid product component is located in chamber 23 above the plunger top 26. The chamber is surrounded by the remaining length 24 of the cylinder 2, the dome 8 and the closure mechanism 11.
In the execution example illustrated here, the plunger top 26 has a cavity 25 in the side turned toward chamber 23, and has an outer surface in the shape of a truncated cone, bulging outward, i.e. convex. Parts of the convex surface 26 can strike from within against the dome-like top section or against the closure mechanism, as soon as the plunger 14 has reached its upper end position. The spike 45 on the underside of the valve disk 43 then penetrates the cavity 25. The spike can have the form of a sharp-pointed needle, but also any other form suitable for bursting the seal 16 can be used.
The cavity 25 in the plunger top 26 has a sealing foil 16, either glued on or soldered on, which can be attached either on the upper side of the plunger top 26 or onto a ledge 28 encircling the cavity 25 (illustrated here in the first case). The reactive component is located in the chamber 18 defined by the cavity 25 and the foil 16, and is released when, after full expulsion of the filling through the valve, the plunger 14, reaching the upper end position, protrudes into the dome 8 and presses the foil 16 against the spike 45, which causes it to rip.
The reactive component in chamber 18 is introduced into the plunger when it is produced, and placed into the pressurized can along with the plunger.
When filling the can, the product component is first introduced into the can while still open, using a certain amount of propellant gas if it is a foaming agent. After flanging the rim of the disk 10 around the rim 9, the can is closed. After filling the foaming agent, the propellant is placed into the lower can area with the aid of a filling needle inserted through the opening 21 and the rubber valve ring 22. Once the necessary pressure has been achieved in the propellant gas chamber 20, the filling needle is removed, after which the one-way valve shuts itself automatically under the pressure of the propellant gas. Then, the can is ready for use.
When executing the pressurized can for the expulsion of building foam according to the invention, it is advisable that propellant gas can pass into the filling (or chamber) 23 through the space between the plunger shirting 15 and the cylinder wall 2, to make available a portion of the gas for expansion. However, by properly fitting the plunger shirting to the inner cylinder wall, the liquid filling from the chamber 23 cannot penetrate into the propellant gas chamber 20, regardless of the can's position.
Such a pressurized can for building foam is activated by tilting the valve 12 with the valve disk 43. Once the valve is opened by tilting the valve disk 43, foaming agent comes out and the plunger 14 moves upward. In FIG. 1, the position of the plunger indicates that the can is about half empty. As soon as the valve 12 is closed, the plunger 14 remains in its current position, moving upwards again when the valve is opened.
Finally, the plunger reaches its upper end position, in which it strikes up against the dome 8, or the foil 16 strikes against the spike 45. The reactive component escapes from the chamber 18. Now, the propellant gas bearing the remaining foaming agent also distributes the reactive component in the now very small, almost closed chamber 23, allowing for a reaction of the remaining foaming agent with the reactive component which converts the former into non-toxic byproducts. These byproducts remain in the can and are disposed of along with the can. Disposal can be through the usual landfills or incinerators if the propellant gas volume is measured in such a way that no or only very small residues remain in the pressurized can.
FIG. 3 shows useful execution forms in cross-section of the plunger used in the pressurized can according to the invention. The plunger according to FIG. 3a shows a foil 16 glued or soldered onto the plunger top 16 above the circular cavity 25. The reactive component is located in the chamber 18 defined by the foil 16 and the cavity 25.
FIG. 3b shows another execution form in which the cavity 25 has a ledge or rim 28 running around its circumference, onto which the foil 16 is glued. This execution form has the advantage that a greater portion of the product component can be emptied out before the reactive component is activated, which also reduces the amount of the reactive component required. The ledge 28 within the cavity 25 can be placed higher or lower in the cavity 25, depending on the shape of the can dome and the amount of the reactive component required.
FIG. 3c shows a third variation in which the sealing foil 16 is combined with a lining 29 of the cavity 25 to form a pouch. The pouch is fitted into the cavity 25, by mechanical means, for instance--using ledges--or by adhesion. The variation allows for individual placement of the reactive component into the plunger 14. It also makes it possible to use water as the reactive component in a plunger made from polyethylene and propylene, if the pouch is made of aluminum foil, which is impermeable for water. | A pressurized can for the expulsion of building foams such as single-component polyurethane foams, the body of which is a cylinder, with a preferably pushed-in bottom. The body also includes a dome-like top section with a valve which expels the can contents consisting of a product component and a propellant. A floating plunger mounted on the interior wall of the cylinder separates the propellant gas chamber from the product component. The floating plunger has a cavity in its upper side, in which a component reactive with the product component is sealed off from the product component by a seal. A trigger device is placed in the dome-like top section to open the seal when the plunger reaches a position immediately below the dome-like top section. | 1 |
BACKGROUND OF THE INVENTION
A. Field of the Invention
This invention relates to MESFET devices.
B. Prior Art
In the past, the development of MESFET's has been hindered by process complexities and process difficulties including aligning of the gate, source and drain as to each other when using multiple masks and critical steps when approaching submicron size that have disallowed minimizing the source-to-gate, drain-to-gate, and gate channel spacings and related series resistance to any great degree relative to MOSFET's in regards to what is possible with a photolithographic or E-Beam Process.
SUMMARY OF THE INVENTION
It is an important object of the invention to provide a means for fabricating a short channel MESFET with minimal series resistance using a simple process having no critical alignment steps.
It is another important object of the invention to provide a MESFET wherein the Schottky gate, drain, and source are defined by one mask thus fixing the distance between them with no alignments.
It is a further important object of the invention to provide a MESFET wherein a mask is used to define ohmic contact metal from the source/drain areas across a relatively undoped bare substrate to within a predetermined distance (L) of the Schottky gate wherein the predetermined distance (L) is a non-critical short-circuit relative to the surface of the bare substrate.
It is yet another object of the invention to provide a MESFET wherein the source-to-gate and drain-to-source distances are non-critical because the predetermined distance (L) is critically controlled by the single mask that defines it.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other objects, advantages and meritorious features of the invention will become more fully apparent from the following specification, appended claims and accompanying drawing sheets.
The features of a specific embodiment of the invention are illustrated in the drawings in which:
FIG. 1 is a cross-sectional block view of the completed MESFET showing how the spatial orientations of the ohmic contacts (L2) may be offset relative to the source/drain areas without affecting the relative relationships of D1 and D2 to L1.
FIG. 2 is a cross-sectional schematic representation of the MESFET of FIG. 1 at a step in the process where implants into the etched openings have been completed.
FIG. 3 is a cross-sectional schematic representation of the MESFET of FIG. 1 at a step in the process where the threshold implant has been completed.
FIG. 4 is a cross-sectional schematic representation of the MESFET of FIG. 1 at a step in the process where the field implant has been completed.
FIG. 5 is a cross-sectional schematic representation of the MESFET of FIG. 1 at a step in the process where the definition and etch of the Schottky metal has been completed.
FIG. 6 is a cross-sectional schematic representation of the MESFET of FIG. 1 at a step in the process where re-metalization of open contacts has been completed
FIG. 7 is an overhead schematic representation of the Schottky gate and its associated ohmic contact of the MESFET of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring particularly to FIGS. 1 through 7 of the drawings by the characters of reference, there is illustrated a MESFET for carrying out the objects of the invention.
The self-aligned short-channel metal semiconductor field effect transistor (MESFET) 5, as shown in FIG. 1, is operative to have a substrate 105 with a p- doped layer 110 and disposed thereabove an n- doped layer 115. Note that the substrate 105 may be p- doped only. Implanted in the n- doped layer 115 of the substrate is a source(S) n plus (+) area 140 having a given dosage concentration and a drain (D) N plus (+) area 145 whereby a channel area 165 is provided between source 140 and drain 145. Deposited on the surface of the substrate over areas 140/145 and overlapping into the channel area 165 adjacent to the gate region 170 are metal areas 195/200 which function as ohmic contacts for the source and drain areas 140/145 respectively. In addition, Schottky metal has been deposited in the gate region 170 over a portion of the channel area 176 for functioning as a schottky gate 205 having a schottky barrier at 250. It will be appreciated that insomuch as only one mask is used to define the ohmic drain and source contacts or conducting electrodes 195/200 and schottky gate electrode 205, their spatial relation as to each other is relatively fixed. In this embodiment sub-micron distance D1 equals D2 equals L1 for a narrow channel area 165, though this need not necessarily be the case. The ohmic contacts or conducting electrodes 195 and 200 may vary in their relative spatial orientation as to source and drain areas 140/145 respectively. Specifically, the portions 210'/210" of the ohmic contacts 195/200 overlap the channel 165 such that D3 is not ordinarily equal to D4. This is tolerable in that the ohmic contacts 195/200 (acting as conductors) are operative to short-out portions of the surface of the channel area 165 (that is relatively undoped compared to the source/drain areas 140/145) due to the hot metal layers 195/200, when deposited, fusing to the substrate 105; thus the distances D3 and D4 are irrelevant and non-critical since the channel 165 is shorted-out over those distances.
The result of this short-circuiting is to operatively bring the source/drain areas 140/145 effectively to the end of the overlapping portions 210'/210" adjacent the schottky gate 205. Thus the ends of the portions 210'/210" act to bound the effective channel area 165 (D1+L1+D2). Accordingly the (D3 plus D1) and the (D2 plus D4) distances can be plus-micro or more than one micron in size while at the same time D1 and D2 are submicron thereby disallowing the need for critical alignments which in turn allows for preventing possible short-circuiting as between the schottky gate 205 and source/drain areas 140/145 due to the relatively large spatial dimension between these two points. In summary, in the above relatively simple process, there are no critical steps because one can work in the plus-micron range, in regards to the short-circuited overlapping ohmic contact portions 210'/210", and there are no alignment problems insomuch as only one mask for self-aligning need be used to define or fix the spatial orientation of the schottky gate 205 to source/drain areas 140/145. It will be appreciated that in view of the above, dimensions of the submicron source-to-gate/drain-to-gate lengths 190'/190" only limited by the photolithographic or E-beam process itself and thus the process can be reliably used to form devices down to the submicron or VLSI range. By limiting the lengths of the spacings 190'/190" and the schottky gate 205, the effective channel area may be relatively very narrow and thus the series resistance is very strictly minimized while the frequency (gain) response is maximized. The series resistance is measured from the edge of the overlapping and extended portion 210'/210" closest to the schottky gate 205 to the edge of the schottky gate 205 itself.
As a first major step in the process for creating a MESFET 5 having multiple substeps as shown in FIG. 2, a silicon substrate 105 is p minus (-) doped as a layer 110 and n minus (-) doped relatively near the surface as a layer 115. A thin oxide layer is grown on the surface of the substrate 105 as silicon dioxide (SiO 2 ) layer 120. A thin layer 125 of Silicon Nitride (Si 3 N 4 ) is deposited on the surface of the SiO 2 layer 120. A photolithographic subprocess including substeps of depositing a layer 132 of photoresist, masking and exposing selected areas with ultraviolet UV light and etching away the exposed areas as openings down to the surface of the substrate 105 with an acid bath thereby defining source and drain regions 130, 135 respectively. Next, the exposed source and drain regions 130, 135 are implanted or otherwise doped to be n+ to a predetermined depth 137 and concentration thereby creating source and drain (n plus) areas 140, 145 respectively.
As a second major step in the MESFET process having multiple substeps, as shown in FIG. 3, the photoresist layer 132 is stripped. A hot oxygen containing gas is applied to oxidize the exposed source and drain regions 130, 135 thereby reforming a SiO 2 layer 120' and 120" to a depth slightly below 150' and 150" the surface of the substrate 105 and to a height slightly above 155' and 155" the surface of the Si 3 N 4 layer 125. It will be appreciated that the Si 3 N 4 layer 125 will not appreciably react with the hot oxygen containing gas. Next, a drive implant is accomplished by heating the source and drain regions 130/135 in a furnace to activate them and drive the source and drain areas 140/145 even deeper to a depth 160'/160". Finally, a thermal implant is made by shooting ions through the Si 3 N 4 layer 125 and the SiO 2 layers 120, 125' and 125" to drive them relatively shallowly into the surface of the substrate 105 and heating in a furnace only to the extent of activating, but not driving the affected area 165 any deeper. It will be appreciated that the whole surface of the substrate 105 is uniformely affected, but only the gate region 170 to be is of interest at this point and thus will be arbitrarily designated the affected area or channel area 165. It will be further appreciated that the threshold implant refers to the threshold voltage in the channel area 165 that may be controlled by a gate voltage described infra.
As a third major step in the process for creating a MESFET 5 having multiple substeps, as shown in FIG. 4, a photolithographic subprocess including the substeps of depositing a layer 176 of photoresist, masking and exposing selected areas with UV light, and etching away the exposed areas as openings down to the SiN 4 layer 125 with an acid bath thereby defining regions 180' and 180" for subsequent field implantations as described infra. Next, ions are uniformly shot across the surface of the photoresist layer 175 and the exposed field implant regions 180' and 180", but the photoresist layer 175 absorbs the ions whereas the Si 3 N 4 and SiO 2 layer 120/125 in the field implant regions 180'/180" transmit them through to the surface of the substrate 105 for relatively shallow implantation therein as field implant areas 185'/185". The field implant areas 185'/185" are relatively p plus and thus operative to provide MESFET inter-device isolation.
As a fourth major step in the process for creating a MESFET 5 having multiple substeps, as shown in FIG. 5, strip the photoresist layer 175 through the use of an acid bath or organic solvent or plasma stripping. The field implant areas 185'/185" are driven by heating in a furnace thereby activating the areas 185'/185" and extending the depths thereof to a predetermined level. The Si 3 N 4 layer 125 is uniformly etched away via an acid bath. The SiO 2 layer 120 is uniformly stripped away also via an acid bath. The exposed surface of the substrate 105 is then uniformly sputter deposited or evaporated with a metalizing layer of predetermined depth of tungsten (W) or molybdenum (Mo), or other suitable materials. Finally, a photolithographic subprocess including the substeps of depositing a layer (not shown) of photoresist, masking and exposing selected areas with UV light, and etching away the exposed areas as opening down to the surface of the substrate 105 with an acid bath thereby defining regions 190'/190" from source-to-gate and drain-to-gate respectively and conversely the ohmic contacts 195, 200, and schottky gate 205 for source, drain and gate respectively. It will be appreciated that the metalizing layer used for the ohmic contacts 195, 200 is schottky metal and in fact is only needed for the schottky gate 205, but on the other hand schottky metal performs more than adequately as an ohmic contact. Accordingly, the ohmic contacts 195, 200 and schottky gate 205 can all be laid down with one mask thereby eliminating alignment and critical step problems. Specifically, the portions 210', 210" of the ohmic contact 195, 200 from the source and drain nearest the schottky gate 205 are allowed to overlap and extend onto the bare silicon substrate 105 in such a manner that the ohmic contacts 195, 200 and schottky gate 205 keep their relative spatial orientation as to each other insomuch as they are all laid down by one and the same mask even though they may all slightly shift uniformly in one direction when being laid down or defined by the mask. It will be further appreciated that the portions 210'/210" of the ohmic contacts 195/200 that are in contact with the bare silicon of the substrate 105 act to short-circuit the surface of the substrate (due to the metal layer 195/200 when deposited fusing as a metallic electrically conductive layer to the substrate 105) from the portion 210'/210" nearest the source/drain area 140/145 to the portion 210'/210" nearest the source-to-gate/drain-to-gate regions 190'/190" thus making the portions 210'/210" length relatively noncritical. The result of this short-circuiting is to operatively electrically bring the source/drain areas 195/200 effectively to the end of the overlapping portion 210'/210" adjacent the schottky gate 205. Thus the ends of the portions 210'/210" act to bound the effective channel area 165 (D1+L1+D2). It further means that the souce-to-gate and drain-to-gate regions 190'/190" and schottky gate 205 can relatively easily be made at submicron lengths in a production mode at a relatively high success rate without worrying about shorting-out the schottky gate 205 to the source or drain areas 140/145 insomuch as it is self-aligned and self-registered.
As a fifth major step in the process for creating a MESFET 5 having multiple substeps, as shown in FIG. 6, SiO 2 areas 215-1, 215-2, 215-3, 215-4 are thermally grown as thermal oxide in the field implant regions 180'/180" and the source-to-gate and drain-to-gate regions 190'/190". Note that the SiO 2 areas 215 - (1-4) are grown into substrate 105 at a level 220 and above the ohmic contacts 195/200 at a level 225. Oxide is then deposited uniformly over the thermal oxide areas 215 - (1-4), the ohmic contacts 195/200 and schottky gate 205 for passivation. Next, a photolithographic subprocess including the substeps of depositing a layer (not shown) of photoresist, masking and exposing selected area with UV light, and etching away the exposed areas with an acid bath as openings down to the ohmic contacts 195/200 of the source and drain areas 140/145 thereby defining or opening up contacts at 232 and 233. It will be appreciated that the schottky gate 205, as shown in cross-sectional view in FIG. 6 and top view in FIG. 7, has been brought out as an ohmic contact to an oversized pad area 235 where a contact 234 may be opened up. It will be further appreciated that the above is done to insure an ohmic contact 234, for the schottky gate 205 that is submicron in cross-section made by bringing out an oversized pad area 235 functioning as an ohmic contact that is plus micron in cross-sectional size. Finally, a metalizing layer of aluminum is uniformably deposited over the deposited oxide 230 - (1-3) and exposed ohmic contacts 232-4. Then a photolithographic subprocess including the substeps of depositing a layer (not shown) of photoresist, masking and exposing selected areas with UV light, and etching away the exposed area 240 as openings down to the surface of the deposited oxide 230. The remaining metal of the aluminum (Al) metalizing layer comprises source electrode 245-1, drain electrode 245-2 and gate electrode 245-3. It will be further appreciated that the given embodiment could be reverse doped substitute p for n and n for p without affecting the quality of the invention. It will also be further appreciated that plus-micron means greater than micron size whereas submicron means less than micron size.
Among the advantages of the process is the simplicity thereof due to the use of a simple mask for aligning source/drain areas 140/145 to the schottky gate 205. In the exemplified embodiment n minus (-) metal schottky (W or Mo) 205 is used in regards to the n (-) layer 115 of the substrate 105, but p (-) metal is equally adaptable in regards to the substrate 105 with the proper choice of metal as to the schottky gate 205. It will be also appreciated that implants in the substrate 105 such as the source/drain areas 140/145 can be added to or subtracted from to adjust field and improve ohmic contacts, among other features. The embodied structure of the MESFET 5 has a grounded (not shown) (N-) substrate 105 through a short-circuit contact at source area 140 interface (n+/N5) (not shown). By etching through the (n-) layer 115 to the (p-) substrate 110, the entire MESFET chip 5 could be grounded (not shown). It will be further appreciated that if a non-refractory metal is used such as platnium (Pt) or Paladium (Pd), it will form an excellent schottky barrier 250 at the surface of the (n-) layer 115 and an excellent ohmic contact 195/200 at the (n+) source/drain areas 140/145. The thermal oxidation layer 215 - (1-3) step is not absolutely necessary in that the deposited oxide layer 230 - (1-3) step could be adequately used in lieu of. It will also be appreciated that the (n-) layer 115 can be obtained by implantation, as described, or epitaxy (not described). An alternative process might include a shallow (n+) implant at source area 140 and/or drain area 145 to significantly improve ohmic contacts 195/200 and minimize series resistance.
While the above referenced embodiment of the invention has been described in considerable detail with respect to the MESFET, it will be appreciated that other modifications and variations therein may be made by those skilled in the art without departing from the true spirit and scope of the invention. | A MESFET with a relatively short channel and small source-to-gate and drain-to-gate spacing for minimal series resistance and maximum frequency response having no alignments or critical steps. In particular, a mask is used to define schottky metal as ohmic metal from the source/drain areas across a relatively undoped bare substrate to within a predetermined distance L of the schottky gate wherein the predetermined distance is a non-critical electrical short-circuit as to the surface of the bare substrate. Thus the source-to-gate and drain-to-gate distances are non-critical because the predetermined distance L can be as critically controlled as the single mask that defines it. | 7 |
RELATED APPLICATIONS
This application is directed to a tool for running and retrieving of down-hole equipment such as a pack-off device which is disclosed in co-pending patent application Ser. No. 532,997 entitled "Well Pack-Off Apparatus," filed of even date herewith.
BACKGROUND OF THE INVENTION
In setting and retrieving tools of the sort shown in the co-pending application, various tools have been provided. The retrieval tools often differ from the setting tools. This invention is directed to a tool which serves both purposes. It is uniquely qualified to set the pack-off device of the co-pending application, or any other apparatus which functions in like manner. It is likewise adapted to retrieve the pack-off device. It achieves this by reversing the sequence of operation so that the same tool can be used for installation and retrieval.
SUMMARY OF THE INVENTION
The present invention incorporates a solid body having a threaded connection at the upper end to engage a mechanical or hydraulically operated jar. The device includes a solid upper body which has a central drilled axial opening. A solid mandrel is threaded into the axial opening. The mandrel extends downwardly to the lower end and has a flared or tapered lower end. The angle of taper is relatively small, typically in the range of up to 12°. The tapered lower end is a solid plug which expands a set of collet fingers which are slidably mounted for movement along the taper. When the collet fingers move to the lower end of the tapered mandrel, they are flared outwardly. When they move upwardly, they are free to flex inwardly to be reduced in diameter and release a tool or fish. The collet fingers are supported on a circular thimble. It connects to an upper skirt which surrounds the solid mandrel. The skirt has downwardly facing serrations. A second and surrounding cylindrical skirt has upwardly facing serrations. The two skirts relatively slide in and define a tubular volume adapted to receive a compressed coil spring which forces the bottom skirt downwardly. The spring is compressible to force the bottom skirt and the collet fingers downwardly toward the position at which they flare outwardly. The lower skirt, the thimble and collet fingers slide upwardly and downwardly to move from a relaxed and small diameter position to a large diameter position, thereby enabling a pack-off or other tool to be set or retrieved in a well.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view through the running and retrieval tool of the present invention showing details of construction, with the collet fingers in the up position; and,
FIG. 2 is a view similar to FIG. 1 showing the collet fingers in the down and expanded position, at the urging of the elongate coil spring which has been extended.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1, the tool 10 is illustrated. It functions as both a setting and a retrieval tool. The tool 10 includes a threaded upper end 11 which is adapted to be threadedly engaged to a jar of appropriate construction or a swivel or some other form of connector. A shoulder 12 limits the threaded engagement of the connective equipment. The shoulder 12 overhangs a narrow neck 13 to define a fishing shoulder in accordance with API standards. The neck 13 connects to a solid body 14 which flares to a greater diameter. The body 14 is countersunk with an axial bore 16. The body 14 is concentric about the opening 16. A solid mandrel 17 is threaded into the opening 16 and a threaded connection is made at 18 to join the two together. The body 14 is shorter than the solid mandrel 17. The mandrel 17 is substantially long and is of solid construction except for some small holes drilled therein.
A small hole 19 is drilled through the body 14 and the mandrel 17 to define a position for a lock pin which joins the two together, preventing unthreading of the joint 18. The mandrel 17 has a central tubular portion 20 which is of solid construction. The mandrel is drilled with a lateral passage 21 to enable a shear pin to be placed in it. The shear pin 22 is optional, and its use is not required. The solid mandrel is axially drilled at 23. It has an axial passage extending from the lower end toward the upper end. It terminates about half-way through the device. The passage provides a fluid flow route into the tool. This is particularly helpful in avoiding the build-up of pressure from down-hole flow. As the tool is run into a well bore, fluid can flow upwardly through the passage 23 and escapes through a lateral passage 24. The passage 24 is located at some point upstream of the lower end of the passage 23. This provides a pressure release route.
The mandrel 17 includes an enlarged tapered portion 25 at its lower end. The tapered surface 25 flares outwardly at a slight angle, perhaps as much as 12°, but not more than this preferably. It is not necessary to taper at a more severe angle. The lower end of the mandrel 17 is rounded at 26 to define a smooth, easily manipulated surface which has no square corners to snag or hang on other equipment.
The upper body 14 is drilled with the axial tapped passage 16, and includes an appended upper skirt 30. The skirt 30 is spaced outwardly from the upper portion 20 of the mandrel. This defines a tubular cavity in the tool. The skirt 30 terminates at a shoulder 31. The shoulder 31 supports and receives a coil spring 32. The spring is captured on the interior of the skirt 30. The skirt 30 is provided with an upwardly facing set of serrations 36 shown separate in FIG. 2. The serrations 36 preferably comprise a set of threads which have shoulders facing upwardly. They lock with a set of serrations to be described.
The skirt 30 terminates at a lower shoulder 37 which locks upward movement of cooperative equipment. The cooperative equipment includes a ring 40 which is loosely fitted about the mandrel 17. The ring 40 carries a number of collet fingers 41 which extend upwardly. They define a smaller skirt except that they are cut with lengthwise slots 42 which define the various collet fingers. They are provided with external threads 43 which are cut as downwardly facing serrations. The serrations 43 match the serrations 36 and the two sets are adapted to lock together when the lower skirt or ring 40 is moved upwardly. Upward movement jams the serrations together. The collet fingers 41 flex inwardly enabling greater penetration of the smaller collet fingers into the large diameter opening on the inside of the skirt 30, moving the two to a locked positions where the serrations lock with one another. They lock together on axial movement. They are unlocked by threaded disengagement. The threaded disengagement is readily achieved by hand upon retrieval of the tool as will be described. Locking together of the serrations is achieved against the force of the spring 32 which forces the lower skirt dowwnwardly.
The ring 40 is threaded on its outer surface and connects with a large nut 45. The nut 45 encircles the transverse opening 21 to enable a shear pin to be positioned therein. The nut is sufficiently large to move axially of the mandrel 17, clearing the shear pin.
The nut 45 threads to the ring 40 and also joins to a lower sleeve 48. The sleeve 48 surrounds the mandrel and slides on it. The sleeve 48 supports a number of collet fingers 49 which have an integrally formed downwardly facing shoulder 50 and a set of serrations 51. The collet fingers have a slight flare at the bottom as shown at 52 in FIG. 1. This enables them to smoothly slide on the tapered mandrel 17 and flare outwardly as they move along it. As the collet fingers move up and down along the mandrel 17, they are flared outwardly as appropriate. The serrations 51 enable the collet fingers to grasp a fish or other item of interest.
The collet finges are defined by adjacent longitudinal slots 53 cut in the lower skirt 48. Typically four or six collet fingers are adequate. They are relatively thin walled to enable them to flex outwardly. They are made of a metal which is sufficiently resilient to flex outwardly and move inwardly after flexure. The collet fingers are appended to the skirt 48 which moves as a unit in conjunction with the nut 45 and the ring 40. The upper set of collet fingers 41 move with the slidably mounted equipment. The slidably mounted assembly provides the motion for the device to provide locking or retrieval of the tool 10 with a fish or other tool.
The device is used in the following manner. To operate the tool as a pulling tool, it is run down-hole on a jar on a wireline. It is run with the collet fingers 49 in the down position or in the position of FIG. 2. The tapered mandrel portion 26 is run into the fish and the fish is engaged by the collet fingers which flex inwardly enabling the fish to be engaged and snugged against the shoulder 50. After this has been accomplished, the flexure of the collet fingers outwardly holds the fish and enables its retrieval. If the fish does not yield to an upward pull, the operator jars down on the tool, which causes the upper skirt comprised of the collet fingers 41 to move upwardly against the spring because of inertial upset. This inertial movement shears the pin and forces the serrations 36 and 43 together, thereby locking the collet fingers 49 in the up position. This locks the collet fingers opposite a portion of the solid mandrel, which has a relatively narrow diameter, and enables them to flex inwardly on an upward pull on the wireline to retrieve the tool 10. This pulls the tool free of the fish if the fish is badly stuck. At this juncture the tool can be retrieved without the fish. Setting the tool from the position of FIG. 1 to the position of FIG. 2 requires only four or five revolutions to unthread the serrations 43 from the serrations 36.
As a running tool, the shouler 51 is jammed into a tool to be set, such as the pack-off of the co-pending disclosure. The shoulder 50 limits the penetration of the tool into the pack-off or the other device. The collet fingers 49 are forced downwardly on the taper and flare outwardly, thereby locking the tool to be set to the running tool 10. This is accomplished with the serrations 36 and 43 in the position of FIG. 2. The tool to be set and the running tool 10 are run into the drill string. Downward jarring on the apparatus forces the solid mandrel relatively downwardly while the shoulder 50 forces the slidable assembly upwardly. As it slides upwardly, it moves to a portion of the mandrel which is not tapered, and hence of smaller diameter, thereby enabling the collet fingers 49 to flex inwardly. On jarring, the serrations 43 are forced into the serrations 36 and thereby lock the slidable assembly in the up position. This then enables disconnection of the running tool from the tool which is to be left in the well. The jarring on the tool jams and locks the serrations together for retrieval of the tool. Optionally, the shear pin can be placed in the opening 21 to require a minimum of jarring impact from the oil jar tool which must shear the pin prior to locking. This avoids accidental locking of the tool.
The apparatus serves as four tools, a running tool, a pulling tool, and both with or without a shear pin. The shear pin makes operation more difficult, which in many instances is very desirable. The added force which is required to shear the pin can be controlled and observed by the operator at the well head, and makes its operation more desirable.
It is uniquely qualified for use with the apparatus in the related application. Other uses and applications of the tool appear in operation.
The foregoing is directed to the preferred embodiment. The scope is determined by the claims which follow. | A setting and retrieval device for down-hole equipment which includes a solid mandrel tapered at its bottom to a larger diameter which cooperates with a set of surrounding collet fingers which have a shoulder and gripping threads thereon to engage a fish or a tool to be set down hole. The apparatus is used as a running tool and a retrieval tool. The collet fingers slide relative to the taper at the urging of a compressible spring arranged between a slidable thimble which supports the collet fingers. It is locked in the up position by serrations which face one another. | 4 |
FIELD
The present invention is in the field of virtual universes. More particularly, the present invention relates to methods and arrangements to modify the spaces of virtual universes.
BACKGROUND
A virtual universe is a computer-based simulated environment. Users or residents may traverse a virtual universe, inhabit dwellings, and interact with other residents through the use of avatars, two or three-dimensional graphical representations of a character. The environment of a virtual universe may resemble the real world, with real world rules such as gravity, topography, and locomotion; and with social and economic interactions between characters. Many virtual universes allow for multiple residents and provide for communications between the residents. Some virtual universes have many thousands or even millions of residents. Virtual universes may be used for massively multiple player online role-playing games, for social networking, or for participation in imaginary social or business universes.
Virtual universes may provide a useful environment for personal interactions, both business and social. Avatars in virtual universes may undergo a wide range of business and social experiences, and such experiences are becoming more important as business and social transactions are becoming common in virtual universes. In fact, the characteristics of an avatar may play important social, business, and other related roles in virtual universes. One example is Second Life (SL), a privately owned 3-D virtual universe, made publicly available in 2003 by Linden Lab. The SL virtual universe is computed and managed by a large array of servers that are owned and maintained by Linden Lab. The SL client program provides its residents with tools to view, navigate, and modify the SL world and participate in its virtual economy. In 2006, SL had over one million residents. Social and business interactions are important in SL, and these interactions include resident interactions in both personal and business meetings.
A space within a virtual universe can be inadequate for the needs of a virtual universe's residents and designers. As with space in a real world, a virtual universe retail showroom, retail store, home, conference room, or island may not be able to accommodate the number of avatars and objects that a resident or designer of the virtual universe wishes to accommodate. For example, a retailer may purchase real estate on a popular island and build a store. The store is surrounded by other properties, making expansion impossible. The store may then grow in popularity until the store's space can no longer accommodate all of the avatars of customers and the retailer's merchandise and other objects. The retailer needs a permanent expansion. In the real world, and in current virtual universes, the retailer has two alternatives: 1) build a second store and encourage some customers to use it, or 2) move the location of the current store to a new location where its expansion is possible. Neither solution takes advantage of the familiarity and ease-of-use that the store's customers have already accumulated. In theory, another alternative exists, but it is even worse than the others. In this alternative, the building expands into the surrounding, space. For example, a building, that is 20 feet wide may suddenly grow to 100 feet wide, crashing into surrounding buildings, and impinging on other owned spaces, avatars, and landscape features. This alternative is disruptive and may not be allowed in virtual universes.
A second, example of a need for increased space is a virtual universe nightclub whose, owner has booked a popular band to play in the virtual universe. As the show proceeds, more and more avatars arrive, slowing performance of the virtual universe server rendering the nightclub and crowding the space to the point that some customers are turned away. This need for additional space may be temporary. The existing space may suffice except for exceptionally popular acts. A final example is a user of a conference room who arrives only to find it already occupied by another group of users. In this example, the desired additional space—an extra conference room—would be separate from the existing space.
SUMMARY OF THE INVENTION
The problems identified above are in large part addressed by methods and arrangements of modifying spaces in virtual universes. One embodiment provides a method of modifying spaces in virtual universes. The embodiment may involve remapping the interior of a space of a virtual universe. The remapping may include changing the size of the interior of the space, while preserving the spaces bordering the space. The embodiment may include placing avatars and other artifacts in the interior of the space. The embodiment may also include determining a method of accessing the remapped interior of the space.
BRIEF DESCRIPTION OF THE DRAWINGS
Advantages of the invention will become apparent upon reading the following detailed description and upon reference to the accompanying drawings in which like references may indicate similar elements:
FIG. 1 depicts an embodiment of a networked system of devices capable of modifying spaces in virtual universes;
FIG. 2 depicts an embodiment of a computer capable of modifying spaces in virtual universes;
FIG. 3 depicts an embodiment of an apparatus to modify spaces in virtual universes;
FIG. 4 depicts a flowchart of an embodiment of a method to modify spaces in virtual universes;
FIG. 5A depicts an example space in a virtual universe before remapping;
FIG. 5B depicts the example space of FIG. 5A after remapping;
FIG. 6A depicts another example space in a virtual universe before remapping; and
FIG. 6B depicts the example space of FIG. 6A after remapping.
DETAILED DESCRIPTION OF EMBODIMENTS
The following is a detailed description of embodiments of the invention depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the invention. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit, and scope of the present invention as defined by the appended claims. The detailed descriptions below are designed to make such embodiments obvious to a person of ordinary skill in the art.
Generally speaking, methods and arrangements of modifying spaces in virtual universes are contemplated. Embodiments include transformations, code, state machines or other logic to remap the interior of a space of a virtual universe. The remapping may include changing the size of the interior of the space, while preserving the spaces bordering the space. The embodiment may include placing avatars and other artifacts in the interior of the space. The embodiment may also include determining a method, of accessing the remapped interior of the space.
While specific embodiments will be described below with reference to particular circuit or logic configurations, those of skill in the art will realize that embodiments of the present invention may advantageously be implemented with other substantially equivalent configurations.
FIG. 1 depicts a diagram of an embodiment of a networked system 100 of devices capable of modifying spaces in virtual universes. The system 100 includes a network 105 , virtual universe servers 110 , 120 , and 127 respectively connected to network 105 through wireline connections 115 , 125 , and 129 , and a variety of computing devices capable of accessing virtual universes, including:
workstation 130 , a computer coupled to network 105 through wireline connection 135 , personal digital assistant 140 , coupled to network 105 through wireless connection 145 , personal computer 150 , coupled to network 105 through wireline connection 155 , laptop computer 160 , coupled to network 105 through wireless connection 165 ; and mobile phone 170 , coupled to network 105 through wireless connection 175 .
The devices 130 , 140 , 150 , 160 , and 170 may enable a user to interact with a virtual universe. In some embodiments, the devices may run client programs which transmit user input to a virtual universe, receive transmissions from the servers, and process the transmissions. A user's input may establish parameters for the user's account in a virtual universe and cause user objects and avatars to interact with the virtual universe. The transmissions from the servers may contain data representing the interactions. The devices may process the transmissions from the servers to display the interactions or store data about the interactions.
Network 105 , which may consist of the Internet or another wide area network, a local area network, or a combination of networks, may provide data communications among virtual universe servers 110 , 120 , and 127 , and the devices 130 , 150 , 140 , 160 , and 170 .
Virtual universe servers 110 , 120 , and 127 may have installed and operative upon them software to implement a virtual universe. A virtual universe is a computer-based simulated environment. The environment may resemble the real world, with real world rules such as gravity, topography, and locomotion. Users may be represented by two or three-dimensional graphical representations called avatars. Many, but not all, virtual universes allow for multiple users. Avatars may communicate by text or by real-time voice communication using VOIP. Some virtual universes provide massively multiplayer online role-playing games such as EverQuest, Ultima Online, Lineage, World of Warcraft, or Guild Wars. Other virtual universes provide for simulated economic and social interaction in environments where the focus is more on the participation and less on winning and losing. These virtual universes include Active Worlds, There, Second Life, Entropia Universe, The Sims Online, Kaneva, and Weblo. Still other virtual universes, such as Friendster or MySpace, may provide a social networking experience. A user may enter some virtual universes to share favorite blogs or other web sites with other residents. In some embodiments, the space of a virtual universe may be divided into regions, virtual areas of land within the virtual universe, typically residing on a single server.
The arrangement of virtual universe servers 110 , 120 , and 127 and other devices making up the exemplary system 100 illustrated in FIG. 1 is for explanation, not for limitation. Data processing systems useful according to various embodiments of the present Invention may omit a server, or may include additional servers, routers, other devices, and peer-to-peer architectures, not shown in FIG. 1 , as will occur to those of skill in the art. Other embodiments may include fewer or additional servers. In some embodiments, the virtual universe may be implemented on one of the computing devices such as PDA 140 , personal computer 150 , laptop 160 or mobile phone 170 .
Networks in such data processing systems may support many data communications protocols, including for example TCP (Transmission Control Protocol), IP (Internet Protocol), HTTP (HyperText Transfer Protocol), WAP (Wireless Access Protocol), HDTP (Handheld Device Transport Protocol), and others as will occur to those of skill in the art. Various embodiments of the present invention may be implemented on a variety of hardware platforms in addition to those illustrated in FIG. 1 .
Turning to FIG. 2 , depicted is an embodiment, of a computer 200 capable of modifying spaces in virtual universes that includes random access memory (RAM) 205 , a processor 230 or CPU, non-volatile memory 240 , a communications adapter 250 , and an Input/Output (I/O) interface adapter 260 connected by system bus 285 . Stored in RAM 205 is virtual universe administrator 210 and operating system 220 .
Virtual universe administrator 210 may comprise computer program instructions for implementing virtual worlds. Virtual universe administrator 210 may generate and modify the space of a virtual universe and the artifacts and other objects contained in the virtual universe. In some embodiments, virtual universe administrator 210 may represent objects by geometric data, data about textures, and effects data. The location of objects existing in virtual universe space may be represented by geometric data. In some further embodiments, virtual universe administrator 210 may communicate with a user's virtual world client program. The geometric data may be distributed to client programs of users in the form of textual coordinates. The objects may also possess textures which are represented by graphics files and distributed in formats such as JPEG2000 files. Effects data may be transmitted to a user's client program and rendered by the user's client program according to the user's preferences and capabilities of a user's computing device. The computing device may be similar to one of devices 130 , 140 , 150 , 160 , or 170 of FIG. 1 . In other further embodiments, a user may interact with virtual universe administrator 210 through a web browser. Virtual universe administrator 210 may also handle the administrative details of a virtual universe, such as creating and modifying account profiles, logging in, and determining which portions of the virtual universe a user may access.
Virtual universe administrator 210 contains virtual universe remapper 215 . Virtual universe remapper 215 may change the size of the interior of a space of the virtual universe while preserving the spaces bordering the space. The modifying may include placing avatars and other artifacts in the interior of the space. For example, the interior of retail space may be expanded to hold more customers and more merchandise while the exterior of the space remains unchanged. Virtual universe remapper 215 may also administer payment for the remapping, including a calculation of the fee. Virtual universe remapper 215 may receive a user's request for remapping space in a virtual world and may select parameters for remapping the space. The parameters may include whether the remapping is manual or automatic. A manual remapping may constitute a long-lasting remapping. For example, virtual universe remapper 215 may expand the interior of retail space for a new department. The new department may persist until the owner decides to make another change or the virtual universe decides to changes its methods of operation.
An automatic, remapping of space may change the space based upon conditions occurring within the space or within the virtual universe as a whole. Conditions in the room may be dependent on the people or avatars in the room, such as the number of people in the room or the nature of avatars in the room. Conditions dependent upon the virtual universe as a whole may be based upon time of day or virtual universe server load. For example, a remapping may be triggered if the number of people in a room exceeds 5 , if the server has a light load, if the avatars have an associated tag that specifies their importance by some criteria, or number of avatars per square foot, or per cubic foot, is above a threshold. For example, a smart virtual universe room may determine that the number of avatars per square foot, or per cubic foot, is above a threshold, and may then make a request for remapping to expand the space.
Operating system 220 may comprise UNIX™, Linux™, Microsoft Windows™, AIX™, IBM's i5/OS™, or other operating systems useful for modifying spaces in virtual universes as will occur to those of skill in the art. Virtual universe profile translation agent 210 and operating system 220 (components of software) are shown in RAM 205 in FIG. 2 , but many components of such software may be stored in non-volatile memory 240 also. Further, while the components of such are shown simultaneously present in RAM, in some other embodiments, only some of the components of RAM 205 may be present at any given time.
Non-volatile, computer memory 240 may be implemented as a hard disk drive 242 , optical disk drive 244 , electrically erasable programmable read-only memory space (EEPROM or Flash memory) 246 , RAM drives (not shown), or as any other kind of computer memory as will occur to those of skill in the art. Communications adapter 250 may/implement the hardware level of data communications between computer 200 and other computers, such as other computers 255 . The data communications may occur directly or through a network and may include communicating with a virtual universe client program or web browser. Such data communications may be carried out through serially through RS-232 connections, through external buses such as USB, through data communications networks such as IP networks, and in other ways as will occur to those of skill in the art. Examples of communications adapters include modems for wired dial-up communications, Ethernet (IEEE 802.3) adapters for wired network communications, and 802.11a/b/g/n adapters for wireless network communications.
I/O interface adapter 260 implements user-oriented I/O through, for example, software drivers and computer hardware for controlling output to display devices such as display device 265 and audio output device 270 as well as user input from user input device 275 and audio input device 280 . User input device 275 may include both a keyboard and a mouse. Some embodiments may include other user input devices such as speech interpreters, bar code scanners, text scanners, tablets, touch screens, and/or other forms of user input devices. Audio output 270 may include speakers or headphones and audio input device 280 may include a microphone or other device to capture sound.
The computer and components illustrated in FIG. 2 are for explanation, not for limitation. In some embodiments, embedded systems, PDAs, cell phones, BlackBerries® and other computing devices which can connect to a network may modify spaces in virtual universes. In many embodiments, modules to modify spaces in virtual universes may be implemented in hardware, firmware, or in state machines or may form a component of an operating system. In several embodiments, a computing device may contain two or more processors. In various embodiments, a computing device may use point-to-point interconnects to connect processors or to connect a processor and another element of the computing system.
For further explanation, FIG. 3 sets forth a block diagram illustrating an exemplary apparatus 300 for modifying spaces in virtual universes. Virtual universe administrator 300 may administer a virtual universe. It may generate and modify the objects of the virtual universe, control the interactions of residents with the virtual universe, and take care of administrative matters. Virtual universe administrator 300 includes space administrator 310 , bursar 350 , and census 360 . Space administrator 310 may administer the modification of space in the virtual world. Modifications may include changing the size of the interior of space in the virtual universe while preserving the spaces bordering the space. Space administrator 310 includes transformer 320 , navigator 330 , populator 340 , and resource administrator 345 .
Transformer 320 may remap spaces in a virtual universe. Generally speaking, in the remappings, transformer 320 may redefine the interior of a space while leaving intact the spaces next to or bordering the space. The redefinition may change the size of the interior space, may transform the relationships between points in the space, or may do both.
In many embodiments, the remapping may be defined in terms of coordinates. Space administrator 310 may represent space as coordinates. For example, a point in a two-dimensional 20 foot by 20 foot room may be represented by (x, y) where x is the horizontal distance in feet from the bottom left corner and y is the vertical distance in feet from the bottom left corner, where 0≦x,y≦20. In this representation, the point (10, 10) is at the center of the room.
In these embodiments, the remapping may consist of selection of a coordinate grid for the remapped space and the application of a mathematical function to the coordinates of points in the original space to produce coordinates of points in the remapped space. In some further embodiments, the remapping may be linear. For example, a remapping may transform the interior space of the 20 foot by 20 foot room into a 40 foot by 40 foot room. The point (x, y) in the original space may be remapped to the point (2x, 2y) in the remapped space. The effect is to spread out the contents of the room, doubling the distance between objects. In this remapping, the center of the new space is (20, 20). The remapped space has 4 times the area of the original space. The remapped room may hold approximately four times as many avatars as the original room. As another example, the remapped space may again be the 40 foot by 40 foot room, but the mapping may map the point (x, y) to the point (x, y). With this mapping, the contents of the original room are placed in the lower left quadrant of the remapped room. The spatial relationships between those objects are preserved in the remapping. The remapped room is again 4 times as large, and may again hold approximately four times as many avatars or other objects as the original room.
In a few further embodiments, the transformation may contract the space. For example, the remapping may map the original set of points (x, y) into a set of points (x/2, y/2). With this mapping, the volume of the original room has been contracted rather than expanded. The spatial relationships between those objects are preserved in the remapping. The remapped room is now ¼ times as large, and may again hold one-quarter times as many avatars or other objects as the original room. Such a remapping may serve to save computing energy in a case where less space is required than was originally been provided.
In several further embodiments, the transformation may be non-linear. For example, a remapping or rescaling may compress even an infinite-sized space into a cube bounded by −1 and +1. One way to do this makes use of the hyperbolic tangent function:
tanh x = ( ⅇ x - ⅇ - x ) / ( ⅇ x + ⅇ - x )
A non-linear mapping may create a fisheye effect, producing visual distortions. Remapping computations may be performed in many ways that are known in the geometric literature dealing with scaling and related transformations.
As shown in the above examples, in embodiments using coordinates, a change in size of a change in spatial relationships of the interior of a space may be measured by the coordinates of the points in the space. In some other embodiments, a change in size of an interior of a space may be approximately measured by the objects that fit into the space. For example, the remapped space of a business may hold far more avatars than the original space. Similarly, the movement of the objects may demonstrate a change in spatial relationships. For example, an avatar may take 10 steps in the remapped space that would be equivalent to one step prior to the remapping.
In the above embodiments, the remapping produced a single version of the original space. In other embodiments, the remapping may produce multiple versions of the original space. Conceptually, the remapping represents a projection of the original space into a space with an additional dimension, thus allowing different “versions” of the original space to be available. In embodiments with coordinate systems, a coordinate in the additional dimension refers to the particular version. For example, in a traditional 3-dimensional virtual universe, geometric points may represented by coordinates (x, y, z). The first coordinate may indicate horizontal position, the second coordinate may indicate depth, and the third coordinate may indicate height. When multiple versions of a space in this virtual universe are created, the remapping coordinates (x, y, z, w) may be used to represent points. In this case, the remapped space is four-dimensional, and the remapped coordinates may designate locations in the fourth-dimensional space. The w-coordinate may be used to designate the particular copy. For example, (0, 0, 0, 1) may represent the point (0,0,0) in the original space as it appears in the first version of the original space, and (0, 0, 0, 4) may represent the same point in the original space as it appears in the 4 th copy. From a mathematical standpoint, it is possible to then allow avatars to access these higher dimensions which have the same 3-D cross sections with the virtual universes as before the w coordinate was introduced. In many embodiments, the versions of the original space may consist of identical copies of the original space. In some embodiments, the versions may consist of transformations of the original space.
Navigator 330 may control the movement of avatars in the transformed space. When the remapped space has the same dimensions as the original space, navigator 330 may retain the same navigational controls. For example, a user may use the arrow keys. Navigator 330 may determine the distance an avatar travels with a “step.” In many embodiments with a linear transformation as the remapping, an avatar may travel the same distance in the remapped space with each step as the avatar did in the original space. Because the remapped space may be a different size, however, the avatar may require a different number of steps to travel through the complete remapped space. In some embodiments with non-linear transformation, the distance an avatar travels with a step may depend upon the portion of the remapped space in which the avatar is located.
In embodiments with multiple versions of the original space, avatars may “move” between different versions of the original space and thus discover different avatars and meetings in each version. In further embodiments, navigator 330 may provide an additional set of keys for movement among the versions. For example, in a typical three-dimensional virtual universe, a fourth set of axis control keys (e.g., “Page Up”, “Page Down”) may control movement among the versions of the original space. In some other embodiments, navigator 330 may automatically determine which version an avatar enters. For example, a conference room may be transformed into multiple copies. Avatars, representing IBM employees may be sent to one copy of the conference room when they enter the original location, while avatars representing employees of another business may be sent to another copy of the conference room. In still other embodiments, navigator 330 may present a menu of choices of versions of the original space to a user, and the user may select a version.
Populator 340 may fill the remapped space with avatars and other artifacts of the virtual world. In embodiments with a single remapped space, Populator 340 may place the avatars and objects of the original space in the remapped space. In some embodiments with linear transformations, the distance between avatars may grow proportionally. For example, if the dimensions of a room double, the avatars may be located in the remapped room at twice their original distance. In further embodiments, Populator 340 may proportionally increase the size of landmark objects, to allow users to more easily orient themselves. Landmark objects may include doors and other exits, window, murals, and other objects visible from a large portion of the space. In a few embodiments, Populator 340 may insert new objects, such as furniture into the remapped space and expand the apparent boundaries of the space as viewed from within the space. For example, an expanded retail store may contain additional displays, sale items, cash registers, rooms, and furniture.
Resource administrator 345 may assign computational resources to the remapped space. The remapped space may require a different amount of resources than the original space, in order to render objects that may be represented by 3-D geometrical coordinates, meshes, and textures. For example, an increased space may require increased resources. In some embodiments, the server capacity allocated to the work of rendering space may be proportional to the size of the space. The number of servers assigned to rendering remapped space may be equal to the number of servers assigned to rendering the original space times a scaling factor equal to the increase of space. For example, an original space that is a cube with an edge of 1 meter may be remapped to a cube that is 10 meters on an edge. If 1% of a single server was used to render the original space, then 10 servers may now be employed. This calculation may, however, represent an upper-bound to the new server requirements. In practice, most of the remapped space may be empty, and the server capacity calculated by the formula may not be actually needed.
Resource administrator 345 may adopt multiple strategies for assigning computational resources to the remapped space Remapped spaces can be handled by the same server or servers as the original space, handled by a different server or servers from the original space, and divided among a set of servers as specified by the scaling factor of the remapped space. The assignment of computational resources may involve dynamic load rebalancing over the available servers in order to accomplish rendering of the new remapped space.
In some embodiments, virtual world 300 may require a fee for the remapping. For example, embodiments which charge fees based upon space may charge an additional fee for increased space. A user who remaps the interior of an apartment into a luxury suite may pay a fee. Similarly, a retailer who requests an expansion of retail space may pay a fee. These remapping operations may require more sophisticated computations and use more computational and bandwidth resources to render the remapped spaces. Bursar 350 may arrange to collect the fee from the user.
Space administrator 310 may offer a variety of transitions between the original space and the remapped space. The possible relationships include:
Immediate replacement: The remapping may be one-time and immediate (static). Conventional movement into the original space may immediately transfer a user into the remapped space. In some embodiments, the replacement may occur while the space is occupied. Avatars in tire original space at the time of remapping may be immediately transferred to the remapped space. Gradual replacement: The space may be remapped continually with time based upon a condition occurring in the interior space or in the virtual universe. These conditions may include, but are not limited to, the number or density of people in the room, time of day, the virtual universe server load, and the nature of avatars in the room. Census 360 may measure the number of people in the room or otherwise determine satisfaction of the condition, and may notify transformer 320 when it is time to remap the space. User-initiated replacement: When the remapped space contains multiple versions of the original space, the user can choose to move into the remapped space by unconventional means, such as movement into another dimension or calling up a new “version” of the original space.
A few examples may illustrate the remapping process and possible advantages of the process. In the first example, a retail store becomes too small for the merchant's needs. The merchant's customers may no longer comfortably fit within the interior or the merchant may desire additional space to display additional merchandise. The merchant may request a static remapping of the entire space inside the store into a new, much larger space. A transformer, such as transformer 320 , may remap the space. Optionally, a bursar, such as bursar 350 , may collect a fee from the merchant. The experience of a user may be to observe the same storefront and building exterior as before, including the size of the exterior and the distance from surrounding buildings. Upon entry into the store, the space appears much larger to the user, and can accommodate more avatars and objects. Exits from the store may all be proportionally located relative to their appearance from the outside. A user may, therefore, remain aware of the user's location both within the store and within the virtual universe outside of the store interior.
In the second example, the owner of a virtual universe nightclub has booked a popular band to play in the club. As the show proceeds, more and more avatars arrive, slowing performance of the virtual universe server or servers rendering the nightclub, and crowding the space to the point that, some customers are turned away. The owner may purchase an option for a dynamic remapping of the space inside the nightclub into a new, larger space. This remapping occurs only when the space becomes crowded. The experience of a nightclub visitor would then be such that as the crowd grows, the distance between landmark objects in the club (e.g., the stage, the bar, the exit) grows proportionally, thus allowing, for more avatars to fit in the space, and for an easier distribution of the nightclub computational load among several servers.
As a final example, a member of a group scheduled to meet for a conference may arrive at a conference room only to find it already occupied by another group. The group member may request a one-time remapping of the space inside the conference room into two or more versions of the conference room. One version may remain occupied. Members of the group unable to meet in the original conference room may enter another version of the conference room by entering the occupied conference room, then moving into the remapped space. The remapped space appears empty and available for use. In physical and mathematical terms, the other versions of the conference room constitute identical copies of the original conference room projected into the fourth dimension. Avatars may move between different versions of the conference room (i.e., move through this new, fourth dimension), encountering different avatars and meetings in each version. Movement may be controlled by using a fourth set of axis control keys, such as “Page Up” and “Page Down”.
The modules of FIG. 3 are for illustration and not limitation. An apparatus for modifying spaces in virtual universes in accordance with embodiments of the invention may omit some of the modules shown, may include additional modules, or may contain different arrangements of modules. In particular, a bursar may be omitted from virtual universe that do not charge fees. Similarly, a census may be omitted if the virtual world does not offer dynamically changing space.
FIG. 4 depicts a flowchart 400 of an embodiment of a method to modify space in a virtual universe. Flowchart 400 of FIG. 4 begins with receiving a request for remapping (element 410 ). A resident of a virtual universe may desire additional space or otherwise desire a remapping of space. For example, the resident may wish to convert an ordinary apartment into a luxury apartment or to expand a retail establishment. Alternatively, the resident may be unable to use common space. For example, a group may be unable to use a conference room, because another group is meeting there. The resident may then inform the virtual universe of the need for additional space.
The virtual universe may select the parameters of the remapping (element 420 ). One parameter may govern the type of spatial transformation (element 425 ). Some remappings may produce another version of the original space. Some of these remappings may be linear. For example, the interior of a room may be doubled in size, with the distance between avatars doubled. Other remappings may be non-linear. In a nonlinear (e.g. fisheye) mapping, a room may be able to hold more avatars that are visible to each other—but visual distortions may be produced. In a few remappings, multiple versions of an original space may be produced. For example, several versions of a conference room may be produced, to allow multiple meetings simultaneously. A version may consist of a copy of the original space or a transformation of the original space. The remapping computations may be performed in many ways that are known in the geometric literature dealing with scaling and related transformations.
Another parameter may govern the duration of the remapping (element 430 ). Some remappings may be of long-term duration (static). For example, a resident may manually request that his house be doubled in size, as perceived from within the space, without actually growing the house into his neighbor's yard. The interior of the house may remain doubled in size until the resident requests additional space, or the resident quits the virtual universe, or some other new circumstance arises.
Other remappings may be dynamic, based upon conditions within the space. For example, a smart virtual universe room may determine that the number of avatars per square foot, or per cubic foot, is above a threshold and then make a request for remapping. Still other remappings may be temporary. For example, the interior of a conference room may be temporarily remapped into multiple copies when two groups attempt to meet at the same time. The additional copies may be removed from the virtual universe after the meetings have completed.
Another parameter may govern the method of accessing the remapped interior of the space (element 435 ). In many embodiments of remappings with a single version of the original space, the methods of navigating to the original space may govern access to the remapped space. For example, a resident may use the same keys of the keyboard to navigate to the space. In some embodiments of remappings with multiple versions of the original space, a resident may use additional keys to select among the copies. In other embodiments, the virtual universe may provide a menu, and a resident may select the appropriate version of the space from the menu. In a few embodiments, the virtual universe may insert the resident in a version of the remapped space based upon information about the resident. For example, an IBM resident may be placed in a conference room for an IBM meeting, while an employee of another corporation may be placed in a different conference room.
The virtual world may assign computational resources to render the space after remapping (element 438 ). A remapped space may require additional computational resources. The remapped space may be capable of holding more objects. As an object may be represented by 3-D geometrical coordinates meshes, and textures, additional objects may require additional resources. In many embodiments, the computational resources may be provided by servers. As an upper bound, the servers assigned to a space may be made proportional to the size of the space.
Several strategies for computing the remapped space are available. In some cases, a virtual universe may utilize dynamic load rebalancing over the available servers in order to accomplish rendering of the new remapped space. In many cases, the remapped space may be handled by the same server as the original space. For example, both the original space and the remapped space may constitute a small portion of a region of the virtual universe handled by a single server. In a few cases, the remapped space may be handled by a different server than the original space. In several cases, rendering the remapped space may be divided among a set of servers as specified by the scaling factor of the remapped space.
If the remapping is a one-time, permanent remapping (manual) (element 440 ), the virtual universe may perform the remapping (element 450 ). For example, a resident may wish to permanently convert an apartment to a luxury apartment. If the remapping depends on conditions (automatic), the virtual universe may check whether the condition has occurred (element 460 ). For example, a nightclub may automatically expand to keep below a certain density of avatars. If the condition has occurred, the virtual universe may remap the space (element 450 ). If the condition has not occurred, the virtual universe may keep checking for the occurrence of the condition (looping through element 460 ).
Element 490 provides an expanded view of element 450 . Remapping includes changing the size of the interior of the space (element 492 ), preserving the spaces bordering the space (element 495 ), and placing artifacts in the interior of the space (populating the space) (element 498 ). The artifacts may include avatars.
Changing the size of the interior of the space (element 492 ) may be performed according to the parameters selected in element 425 . In many instances, changing the size of the interior of the space constitutes increasing the size of the space. A resident may request a remapping in order to obtain additional space, either personal space or business space. While the remapping of FIG. 4 changes the size of the interior of the space, it preserves the spaces bordering the space (element 495 ). For example, the interior of an apartment may be quadrupled in size, but the adjoining apartments, walls, and hallways are not moved. An external view of the apartment may not disclose the roomier interior. The appearance of the apartment to a user on the outside may remain the same as before the remapping. Upon entry into the apartment, however, the resident would see the expanded interior space.
In populating the remapped interior (element 498 ), the virtual universe may use the artifacts from the original space or may use new artifacts, or may use a combination of both. The artifacts from the original space may be spread throughout the remapped space or placed in a portion of the remapped space corresponding to the original space. For example, a remapping may double the length and width of a nightclub. The avatars in the nightclub before the remapping may be spread throughout the expanded nightclub proportionately; that is, an avatar at location (x, y) in the original space may be placed at location (2x, 2y) in the expanded space. Other artifacts from the original space, such as tables and chairs, may also be placed in the expanded, space. Additional tables and chairs may also be placed in the expanded space. The avatars in the remapped space may be the same size as in the original space, and thus proportionately smaller. Some landmark artifacts, such as murals, windows, and doors, may be rendered larger, to increase visibility and enable residents to navigate more easily through the space. As another example, a retail space may be remapped to allow space for a new department. Avatars and other artifacts in the current departments may be placed in the same locations in the remapped space. The new department may be populated with new counters, new fixtures, and new merchandise.
The embodiment of FIG. 4 is for illustration and not for limitation. Other embodiments may add or subtract elements or perform them in a different order. In some embodiments, a virtual universe may charge a fee for remapping space. In many embodiments, dynamic remappings may not be available, and element 460 may be omitted.
FIG. 5A depicts ah example of a space before remapping and FIG. 5B depicts the space after remapping. The exterior view 500 of the original space ( FIG. 5A ) shows four spaces, space 1 ( 505 ), space 2 ( 510 ), space 3 ( 515 ), and space 4 ( 520 ) with some separation. The space, for example, may consist of offices and the separation may be a hallway. The interior view of space 2 ( 530 ) shows three avatars ( 540 , 545 , and 550 ) around a conference table ( 555 ).
FIG. 5B shows the space of FIG. 5A after the remapping of the interior of space 510 . The exterior view 560 of the remapped space in FIG. 5B also shows four spaces, space 1 ( 565 ), space 2 ( 570 ), space 3 ( 575 ), and space 4 ( 580 ) with some separation. The exterior view 560 of the remapped space is identical to the exterior view 500 of the original space. In particular, the remapping of the interior of space 2 ( 585 ) did not affect the exterior of space 2 ( 570 ), the exteriors of spaces 1 , 3 , and 4 ( 565 , 575 , and 580 respectively), or the separations between the spaces.
The interior view 585 of the remapped space shows an expansion of the interior of the original space 2 . The remapped interior has the same width and roughly twice the height. The interior of space 2 is populated with the artifacts of the original space (avatars 540 , 545 , and 550 and conference table 555 ) and additional artifacts (avatars 590 and 593 and conference table 597 ). The original artifacts are positioned in an area corresponding to the original space and the new artifacts are positioned in a separate space.
Turning to FIGS. 6A and 6B , shown is another example of a space, before remapping ( FIG. 6A ) and after remapping ( 6 B). In the examples of FIG. 6 , three copies of the original interior space are created in the remapped space, but the three copies have a single exterior. The exterior view 600 of the original space ( FIG. 6A ) shows four spaces, space 1 ( 605 ), conference room ( 610 ), space 3 ( 615 ), and space 4 ( 615 ) with some separation. The interior view 625 of the conference room ( 630 ) shows space containing a conference table ( 640 ).
The exterior view 643 of the remapped space in FIG. 6B also shows four spaces, space 1 ( 645 ), conference room ( 650 ), space 3 ( 655 ), and space 4 ( 660 ), with some separation. The exterior view 643 of the remapped conference room is identical to the exterior view 600 of the original space. In particular, the remapping of the interior of conference room 610 did not affect the exterior 650 of conference room, the exteriors of spaces 1 , 3 , and 4 ( 645 , 655 , and 660 respectively), or the separations between the spaces.
The interior view 665 of the remapped space shows three copies of the interior of the original space, conference rooms 670 , 675 , and 680 . Conference room 680 contains a conference table ( 685 ). In FIG. 6B , the remapping has created three copies of the original space. In some embodiments, a resident may navigate to the exterior 650 of the remapped conference room and use a set of navigation keys to reach the desired interior, one of 670 , 675 , or 680 .
The invention can take the form of an entirely hardware embodiment; an entirely software embodiment or an embodiment containing both hardware and software elements. In a preferred embodiment, the invention is implemented in software, which includes but is not limited to firmware, resident software, microcode, etc.
Furthermore, the invention can take the form of a computer program product for modifying spaces in virtual universes, the computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system. For the purposes of this description, a computer-usable or computer-readable medium can be any apparatus that can store the program for use by or in connection with the instruction execution system, apparatus, or device.
The medium can be an electronic, magnetic, optical, or semiconductor system (or apparatus or device). Examples of a computer-readable medium include a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM), a read-only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk—read only memory (CD-ROM), compact disk—read/write (CD-R/W) and DVD.
A data processing system suitable for storing and/or executing program code will include at least one processor coupled directly or indirectly to memory elements through a system bus. The memory elements can include local memory employed during actual execution of the program code, bulk storage, and cache memories which provide temporary storage of at least some program code in order to reduce the number of times code must be retrieved from bulk storage during execution.
Input/output or I/O devices (including but not limited to keyboards, displays, pointing devices, etc.) can be coupled to the system either directly or through intervening I/O controllers.
Network adapters may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters.
It will be apparent to those skilled in the art having the benefit of this disclosure that the present invention contemplates methods and arrangements for modifying spaces in virtual universes. It is understood that the form of the invention shown and described in the detailed description and the drawings are to be taken merely as examples. It is intended that the following claims be interpreted broadly to embrace all the variations of the example embodiments disclosed.
Although the present invention and some of its advantages have been described in detail for some embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Although an embodiment of the invention may achieve multiple objectives, not every embodiment falling within the scope of the attached claims will achieve every objective. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. | Methods and arrangements of modifying spaces in virtual universes are discussed. Embodiments include transformations, code, state machines or other logic to receive data from a software agent in a virtual universe, directly or indirectly. The data may be based upon information automatically gathered from data stores outside the virtual universe, including account data and user profile data. The embodiment may also involve developing a user profile of the user in the virtual universe, based upon the data received from the software agent. An embodiment may also involve automatically gathering information from data stores external to the virtual universe. The information may include user account data and user profile information. The embodiment may also include aggregating data for generating the user profile in the virtual universe, based upon the information; and transmitting the data directly or indirectly to the virtual universe. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
This is a divisional of U.S. Ser. No. 08/641,384, filed Apr. 30, 1996, now U.S. Pat. No. 5,696,267 which is a continuation-in-part of U.S. Ser. No. 08/460,819, filed Jun. 1, 1995, now abandoned which is a continuation-in-part of U.S. Ser. No. 08/432,740, filed May 2, 1995. now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a genus of substituted oximes, hydrazones and olefins useful as antagonists of tachykinin receptors, in particular as antagonists of the neuropeptides neurokinin-1 receptor (NK 1 ) and/or neurokinin-2 receptor (NK 2 ) and/or neurokinin-3 receptor (NK 3 ).
Neurokinin receptors are found in the nervous system and the circulatory system and peripheral tissues of mammals, and therefore are involved in a variety of biological processes. Neurokinin receptor antagonists are consequently expected to be useful in the treatment or prevention of various mammalian disease states, for example asthma, cough, bronchospasm, inflammatory diseases such as arthritis, central nervous system conditions such as migraine and epilepsy, nociception, and various gastrointestinal disorders such as Crohn's disease.
In particular, NK 1 receptors have been reported to be involved in microvascular leakage and mucus secretion, and NK 2 receptors have been associated with smooth muscle contraction, making NK 1 and NK 2 receptor antagonists especially useful in the treatment and prevention of asthma.
Some NK 1 and NK 2 receptor antagonists have previously been disclosed: arylalkylamines were disclosed in U.S. Pat. No. 5,350,852, issued Sep. 27, 1994, and spiro-substituted azacycles were disclosed in WO 94/29309, published Dec. 22, 1994.
SUMMARY OF THE INVENTION
Compounds of the present invention are represented by the formula I ##STR4## or a pharmaceutically acceptable salt thereof, wherein: a is 0, 1, 2 or 3;
b and d are independently 0, 1 or 2;
R is H, C 1-6 alkyl, --OR 6 or C 2 -C 6 hydroxyalkyl;
A is ═N--OR 1 , ═N--N(R 2 )(R 3 ), ═C(R 11 )(R 12 ) or ═NR 25 ;
X is a bond, --C(O)--, --O--, --NR 6 --, --S(O)e--, --N(R 6 )C(O)--, --C(O)N(R 6 )-- --OC(O)NR 6 --, --OC(═S)NR 6 --, --N(R 6 )C(═S)O--, --C(═NOR 1 )--, --S(O) 2 N(R 6 )--, --N(R 6 )S(O) 2 --, --N(R 6 )C(O)O-- or --OC(O)--, provided that when d is 0, X is a bond, --C(O)--, --NR 6 --, --C(O)N(R 6 )--, --N(R 6 )C(O)--, --OC(O)NR 6 --, --C(═NOR 1 )--, --N(R 6 )C(═S)O--, --OC(═S)NR 6 --, --N(R 6 )S(O) 2 -- or --N(R 6 )C(O)O--; provided that when A is ═C(R 11 )(R 12 ) and d is 0, X is not --NR 6 -- or --N(R 6 )C(O)--; and provided that when A is ═NR 25 , d is 0 and X is --NR 6 -- or --N(R 6 )C(O)--;
T is H, R 4 -aryl, R 4 -heterocycloalkyl, R 4 -heteroaryl, phthalimidyl, R 4 -cycloalkyl or R 10 -bridged cycloalkyl;
Q is R 5 -phenyl, R 5 -naphthyl, --SR 6 , --N(R 6 )(R 7 ), --OR 6 or R 5 -hetero-aryl, provided that when Q is --SR 6 , --N(R 6 )(R 7 ) or --OR 6 , R is not --OR 6 ;
R 1 is H, C 1-6 alkyl, --(C(R 6 )(R 7 )) n --G, --G 2 , --(C(R 6 )(R 7 )) p --M-- (C(R 13 )(R 14 )) n --(C(R 8 )(R 9 )) u --G, --C(O)N(R 6 )--(C(R 13 )(R 14 )) n --(C(R 8 )(R 9 )) u --G or --(C(R 6 )(R 7 )) p --M--(R 4 -heteroaryl);
R 2 and R 3 are independently selected from the group consisting of H, C 1-6 alkyl, --CN, --(C(R 6 )(R 7 )) n --G, --G 2 , --C(O)--(C(R 8 )(R 9 )) n --G and --S(O) e R 13 ; or R 2 and R 3 , together with the nitrogen to which they are attached, form a ring of 5 to 6 members, wherein 0, 1 or 2 ring members are selected from the group consisting of --O--, --S-- and --N(R 19 )--;
R 4 and R 5 are independently 1-3 substituents independently selected from the group consisting of H, halogeno, --OR 6 , --OC(O)R 6 , --OC(O)N(R 6 )(R 7 ), --N(R 6 )(R 7 ), C 1-6 alkyl, --CF 3 , --C 2 F 5 , --COR 6 , --CO 2 R 6 , --CON(R 6 )(R 7 ), --S(O) e R 13 , --CN, --OCF 3 , --NR 6 CO 2 R 16 , --NR 6 COR 7 , --NR 8 CON(R 6 )(R 7 ), R 15 -phenyl, R 15 -benzyl, NO 2 , --N(R 6 )S(O) 2 R 13 or --S(O) 2 N(R 6 )(R 7 ); or adjacent R 4 substituents or adjacent R 5 substituents can form a --O--CH 2 --O-- group; and R 4 can also be R 15 -heteroaryl;
R 6 , R 7 , R 8 , R 6a , R 7a , R 8a , R 13 and R 14 are independently selected from the group consisting of H, C 1-6 alkyl, C 2 -C 6 hydroxyalkyl, C 1 -C 6 alkoxy-C 1 -C 6 alkyl, R 15 -phenyl, and R 15 -benzyl; or R 6 and R 7 , together with the nitrogen to which they are attached, form a ring of 5 to 6 members, wherein 0, 1 or 2 ring members are selected from the group consisting of --O--, --S-- and --N(R 19 )--;
R 9 and R 9a are independently selected from the group consisting of R 6 and --OR 6
R 10 and R 10a are independently selected from the group consisting of H and C 1-6 alkyl;
R 11 and R 12 are independently selected from the group consisting of H, C 1 -C 6 alkyl, --CO 2 R 6 , --OR 6 , --C(O)N(R 6 )(R 7 ), C 1 -C6 hydroxyalkyl, -(CH 2 ) r --OC(O)R 6 , --(CH 2 ) r OC(O)CH═CH 2 , --(CH 2 ) r --O(CH 2 ) s --CO 2 R 6 , --(CH 2 ) r --O--(CH 2 ) s --C(O)N(R 6 )(R 7 ) and --(CH 2 ) r --N(R 6 )(R 7 );
R 15 is 1 to 3 substituents independently selected from the group consisting of H, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 1 -C 6 alkylthio, halogeno, --CF 3 , --C 2 F 5 , --COR 10 , --CO 2 R 10 , --C(O)N(R 10 ) 2 , --S(O) e R 10a , --CN, --N(R 10 )COR 10 , --N(R 10 )CON(R 10 ) 2 and --NO 2 ;
R 16 is C 1-6 alkyl, R 15 -phenyl or R 15 -benzyl;
R19 is H, C 1 -C 6 alkyl, --C(O)N(R 10 ) 2 , --CO 2 R 10 , --(C(R 8 )(R 9 )) f --CO 2 R 10 or --(C(R 8 )(R 9 )) u --C(O)N(R 10 ) 2 ;
f, n, p, r and s are independently 1-6;
u is0-6;
G is selected from the group consisting of H, R 4 -aryl, R 4 -hetero-cycloalkyl, R 4 -heteroaryl, R 4 -cycloalkyl, --OR 6 , --N(R 6 )(R 7 ), --COR 6 , --CO 2 R 6 , --CON(R 7 )(R 9 ), --S(O) e R 13 , --NR 6 CO 2 R 16 , --NR 6 COR 7 , --NR 8 CON(R 6 )(R 7 ), --N(R 6 )S(O) 2 R 13 , --S(O) 2 N(R 6 )(R 7 ), --OC(O)R 6 , --OC(O)N(R 6 )(R 7 ), --C(═NOR 8 )N(R 6 )(R 7 ), --C(═NR 25 )N(R 6 )(R 7 ), --N(R 8 )C(═NR 25 )N(R 6 )(R 7 ), --CN, --C(O)N(R 6 )OR 7 , and --C(O)N(R 9 )-(R 4 -heteroaryl), provided that when n is 1 and u is 0, or when R 9 is --OR 6 , G is not --OH or --N(R 6 )(R 7 );
M is selected from the group consisting of a double bond, --O--, --N(R 6 )--, --C(O)--, --C(R 6 )(OR 7 )--, --C(R 8 )(N (R 6 )(R 7 ))--, --C(═NOR 6 ) N(R 7 )--, --C(N(R 6 )(R 7 ))═NO--, --C(═NR 25 )N(R 6 )--, --C(O)N (R 9 )--, --N(R 9 )C(O)--, --C(═S)N(R 9 )--, --N(R 9 )C(═S)-- and --N(R 6 )C(O)N(R 7 )--, provided that when n is 1, G is not OH or --NH(R 6 ); and when p is 2-6,M can also be --N(R 6 )C(═NR 25 )N(R 7 )-- or --OC(O)N(R 6 )--;
G 2 is R 4 -aryl, R 4 -heterocycloalkyl, R 4 -heteroaryl, R 4 -cycloalkyl, --COR 6 , --CO 2 R 16 , --S(O) 2 N(R 6 )(R 7 ) or --CON (R 6 )(R 7 );
e is 0, 1 or 2, provided that when e is 1 or 2, R 13 and R 10a are not H;
R 25 is H, C 1 -C 6 alkyl, --CN, R 15 -phenyl or R 15 -benzyl;
Z is ##STR5##
g and j are independently 0-3;
h and k are independently 1-4, provided the sum of h and g is 1-7;
J is two hydrogen atoms, ═O, ═S, ═NR 9 or ═NOR 1 ;
L and L 1 are independently selected from the group consisting of H, C 1 -C 6 alkyl, C 1 -C 6 alkenyl, --CH 2 -cycloalkyl, R 15 -benzyl, R 15 -heteroaryl, --C(O)R 6 , --(CH 2 ) m --OR 6 , --(CH 2 ) m --N(R 6 )(R 7 ), --(CH 2 ) m --C(O)--OR 6 and --(CH 2 ) m --C(O)N(R 6 )(R 7 );
m is 0 to 4, provided that when j is 0,M is 1-4;
R 26 and R 27 are independently selected from the group consisting of H, C 1 -C 6 alkyl, R 4 -aryl and R 4 -heteroaryl; or R 26 is H, C 1 -C 6 alkyl, R 4 -aryl or R 4 -heteroaryl, and R 27 is --C(O)R 6 , --C(O)--N(R 6 )(R 7 ), --C(O)(R 4 -aryl), --C(O) (R 4 -heteroaryl), --SO 2 R 13 or --SO 2 --(R 4 -aryl);
R 28 is H, --(C(R 6 )(R 19 )) t --G, --(C(R 6 )(R 7 )) v --G 2 or --NO 2 ;
t and v are 0, 1, 2 or 3, provided that when j is 0, t is 1, 2 or 3;
R 29 is H, C 1 -C 6 alkyl, --C(R 10 ) 2 S(O) e R 6 , R 4 -phenyl or R 4 -heteroaryl;
R 30 is H, C 1 -C 6 alkyl, R 4 -cycloalkyl, --(C(R 10 ) 2 ) w --(R 4 -phenyl), --(C(R 10 ) 2 ) w --(R 4 -heteroaryl), --C(O)R 6 , --C(O)OR 6 , --C(O)N(R 6 )(R 7 ), ##STR6##
w is 0, 1, 2, or 3;
V is ═O, ═S or ═NR 6 ; and
q is 0-4.
Preferred are compounds of formula I wherein X is --O--, --C(O)--, a bond, --NR 6 --, --S(O) e --, --N(R 6 )C(O)--, --OC(O)NR 6 or --C(═NOR 1 )--. More preferred are compounds of formula I wherein X is --O--, --NR 6 --, --N(R 6 )C(O)-- or --OC(O)NR 6 . Additional preferred definitions are: b is 1 or 2 when X is --O-- or --N(R 6 )--; b is 0 when X is --N(R 6 )C(O)--; and d is 1 or 2. T is preferably R 4 -aryl, R 4 -heteroaryl, R 4 -cycloalkyl or R 10 -bridged cycloalkyl, with R 4 -aryl, especially R 4 -phenyl, being more preferred. Also preferred are compounds wherein R 6a , R 7a , R 8a and R 9a are independently hydrogen, hydroxyalkyl or alkoxyalkyl, with hydrogen being more preferred. Especially preferred are compounds wherein R 8a and R 9a are each hydrogen, d and b are each 1, X is --O--, --NR 6 --, --N(R 6 )C(O)-- or --OC(O)NR 6 , T is R 4 -aryl and R 4 is two substituents selected from C 1 -C 6 alkyl, halogeno, --CF 3 and C 1 -C 6 alkoxy. Preferred definitions for T being R 4 -heteroaryl include R 4 -quinolinyl and oxadiazolyl.
Also preferred are compounds of formula I wherein R is hydrogen. Q is preferably R 5 -phenyl, R 5 -naphthyl or R 5 -heteroaryl; an especially preferred definition for Q is R 5 -phenyl, wherein R 5 is preferably two halogen substituents.
Preferred are compounds of formula I wherein A is ═N--OR 1 or ═N--N(R 2 )(R 3 ). More preferred are compounds wherein A is ═N--OR 1 . R 1 is preferably H, alkyl, --(CH 2 ) n --G, --(CH 2 ) p --M--(CH 2 ) n --G or --C(O)N(R 6 )(R 7 ), wherein M is --O-- or --C(O)N(R 9 )-- and G is --CO 2 R 6 , --OR 6 , --C(O)N(R 6 )(R 9 ), --C(═NOR 8 )N(R 6 )(R 7 ), --C(O)N(R 9 )(R 4 -heteroaryl) or R 4 -heteroaryl. R 2 and R 3 are independently preferably H, C 1 -C 6 alkyl, --(C(R 6 )(R 7 )) n --G or G 2 .
Preferred definitions of Z are ##STR7## with the following groups being more preferred: ##STR8##
This invention also relates to the use of a compound of formula I in the treatment of asthma, cough, bronchospasm, inflammatory diseases such as arthritis, central nervous system conditions such as migraine and epilepsy, nociception, and various gastrointestinal disorders such as Crohn's disease.
In another aspect, the invention relates to a pharmaceutical composition comprising a compound of formula I in a pharmaceutically acceptable carrier. The invention also relates to the use of said pharmaceutical composition in the treatment of asthma, cough, bronchospasm, inflammatory diseases such as arthritis, migraine, nociception, and various gastrointestinal disorders such as Crohn's disease.
DETAILED DESCRIPTION
As used herein, the term "alkyl" means straight or branched alkyl chains. "Lower alkyl" refers to alkyl chains of 1-6 carbon atoms and, similarly, lower alkoxy refers to alkoxy chains of 1-6 carbon atoms.
"Cycloalkyl" means cyclic alkyl groups having 3 to 6 carbon atoms. "Bridged cycloalkyl" refers to C 7 -C 10 saturated rings comprised of a cycloalkyl ring or a fused bicycloalkyl ring and an alkylene chain joined at each end to non-adjacent carbon atoms of the ring or rings. Examples of such bridged bicycloalkyl rings are adamantyl, myrtanyl, noradamantyl, norbornyl, bicyclo 2.2.1!heptyl, 6,6-dimethylbicyclo 3.1.1!heptyl, bicyclo 3.2.1!octyl, and bicyclo 2.2.2!octyl.
"Aryl" means phenyl, naphthyl, indenyl, tetrahydronaphthyl, indanyl, anthracenyl or fluorenyl.
"Halogeno" refers to fluoro, chloro, bromo or iodo atoms.
"Heterocycloalkyl" refers to 4- to 6-membered saturated rings comprising 1 to 3 heteroatoms independently selected from the group consisting of --O--, --S-- and --N(R 19 )--, with the remaining ring members being carbon. Examples of heterocycloalkyl rings are tetrahydrofuranyl, pyrrolidinyl, piperidinyl, morpholinyl, thiomorpholinyl and piperazinyl. R 4 -heterocycloalkyl refers to such groups wherein substitutable ring carbon atoms have an R 4 substituent.
"Heteroaryl" refers to 5- to 10-membered single or benzofused aromatic rings comprising 1 to 4 heteroatoms independently selected from the group consisting of --O--, --S-- and --N═, provided that the rings do not include adjacent oxygen and/or sulfur atoms. Examples of single-ring heteroaryl groups are pyridyl, isoxazolyl, oxadiazolyl, furanyl, pyrrolyl, thienyl, imidazolyl, pyrazolyl, tetrazolyl, thiazolyl, thiadiazolyl, pyrazinyl, pyrimidinyl, pyridazinyl and triazolyl. Examples of benzofused heteroaryl groups are indolyl, quinolinyl, thianaphthenyl and benzofurazanyl. N-oxides of nitrogen-containing heteroaryl groups are also included. All positional isomers are contemplated, e.g., 1-pyridyl, 2-pyridyl, 3-pyridyl and 4-pyridyl. R 4 -heteroaryl refers to such groups wherein substitutable ring carbon atoms have an R 4 substituent.
Where R 2 and R 3 or R 6 and R 7 substituents on a nitrogen atom form a ring and additional heteroatoms are present, the rings do not include adjacent oxygen and/or sulfur atoms or three adjacent hetero-atoms. Typical rings so formed are morpholinyl, piperazinyl and piperidinyl.
In the structures in the definition of Z, the substituents L and L 1 may be present on any substitutable carbon atom, including in the second structure the carbon to which the --N(R 26 )(R 27 ) group is attached.
In the above definitions, wherein variables R 6 , R 7 , R 8 , R 9 , R 10 , R 13 , R 14 , R 15 , R 30 and R 31 , for example, are said to be independently selected from a group of substituents, we mean that R 6 , R 7 , R 8 , R 9 , R 10 , R 13 , R 14 , R 15 , R 30 and R 31 are independently selected, but also that where an R 6 , R 7 , R 8 , R 9 , R 10 , R 13 , R 14 , R 15 , R 30 or R 31 variable occurs more than once in a molecule, those occurrences are independently selected (e.g., if B is ═NR 6 -- wherein R 6 is hydrogen, X can be --N(R 6 )-- wherein R 6 is ethyl). Similarly, R 4 and R 5 can be independently selected from a group of substituents, and where more than one R 4 and R 5 are present, the substitutents are independently selected; those skilled in the art will recognize that the size and nature of the substituent(s) will affect the number of substituents which can be present.
Compounds of formula I can have at least one asymmetrical carbon atom and all isomers, including diastereomers, enantiomers and rotational isomers, as well as E and Z isomers of the oxime, hydrazone and olefin groups, are contemplated as being part of this invention. The invention includes d and I isomers in both pure form and in admixture, including racemic mixtures. Isomers can be prepared using conventional techniques, either by reacting optically pure or optically enriched starting materials or by separating isomers of a compound of formula I.
Those skilled in the art will appreciate that for some compounds of formula I, one isomer will show greater pharmacological activity than other isomers.
Compounds of the invention have at least one amino group which can form pharmaceutically acceptable salts with organic and inorganic acids. Examples of suitable acids for salt formation are hydrochloric, sulfuric, phosphoric, acetic, citric, oxalic, malonic, salicylic, malic, fumaric, succinic, ascorbic, maleic, methanesulfonic and other mineral and carboxylic acids well known to those in the art. The salt is prepared by contacting the free base form with a sufficient amount of the desired acid to produce a salt. The free base form may be regenerated by treating the salt with a suitable dilute aqueous base solution such as dilute aqueous sodium bicarbonate. The free base form differs from its respective salt form somewhat in certain physical properties, such as solubility in polar solvents, but the salt is otherwise equivalent to its respective free base forms for purposes of the invention.
Certain compounds of the invention are acidic (e.g., those compounds which possess a carboxyl group). These compounds form pharmaceutically acceptable salts with inorganic and organic bases. Examples of such salts are the sodium, potassium, calcium, aluminum, gold and silver salts. Also included are salts formed with pharmaceutically acceptable amines such as ammonia, alkyl amines, hydroxyalkylamines, N-methylglucamine and the like.
Compounds of formula I can be prepared using methods well known to those skilled in the art. Following are typical procedures for preparing various compounds; the skilled artisan will recognize that other procedures may be applicable, and that the procedures may be suitably modified to prepare other compounds within the scope of formula I.
Procedure A:
Compounds of formula I wherein R is H, a and d are each 1, X is --O--, Q is R 5 -phenyl, T is R 4 -phenyl, A is ═NOR 1 and the remaining variables are as defined above (see formula , below), can be prepared as shown in the following reaction scheme: ##STR9##
In step 1, the 3-(substituted phenyl)-2-propenoic acid of formula I, wherein R 5 is as defined above, is reacted with an oxidizing agent such as dimethyl dioxirane or m-chloroperoxybenzoic acid (m-CPBA) in an inert organic solvent such as CH 2 Cl 2 or toluene. An acidic catalyst such as Amberlyst 15 or formic acid is added to give the desired lactone 2. Preferable reaction temperatures range from 0° to 60° C. ##STR10## In step 2, lactone 2 is reacted with a suitable hydroxy-protecting group, for example an electrophile such as a compound of formula R 20 --R 17 wherein R 17 is a leaving group such as Cl or Br and R 20 is of the formula ##STR11## wherein R 4 , R 8a , R 9a and b are as defined above, or wherein R 20 is trialkylsilyl. The reaction is carried out in the presence of a silver salt such as Ag 2 O in an organic solvent such as dimethylformamide (DMF) or tetrahydrofuran (THF), most preferably DMF, at a temperature of 0° to about 500° C. ##STR12## In step 3, compound 3 is dissolved in an inert organic solvent such as CH 2 Cl 2 , THF or toluene, preferably CH 2 Cl 2 , and reduced with a reagent such as DiBAL-H at temperatures from about -78° C. to room temperature. ##STR13## In step 4, compound 4 is reacted with an amine of formula 5, wherein Z is as defined above, in an alcohol such as CH 3 OH, CH 3 CH 2 OH or more preferably CF 3 CH 2 OH, in the presence of a dehydrating agent such as molecular sieves and a reducing agent such as NaCNBH 3 or under hydrogenating conditions (H 2 /Pd/C), at a temperature range of 0 to 60° C. ##STR14## In Step 5, a compound of formula 6 is oxidized to the corresponding ketone of formula 7 using an oxidizing agent such as pyridinium chlorochromate (PCC) or Jones reagent, preferably Jones reagent, in a suitable organic solvent such as CH 2 Cl 2 or toluene (for PCC) or acetone (for Jones reagent) at a temperature from about 0° to 50° C. Other suitable oxidizing agents include pyridinium dichromate (PDC), tetrapropylammonium perruthenate(VII)/4-methylmorpholine N-oxide (TPAP/NMO), and (COCI) 2 /DMSO. ##STR15##
In Step 6, the ketone of formula 7 is converted to the corresponding oxime of formula 8 by treatment with a hydroxylamine derivative of the formulaH 2 NOR 1 or a salt thereof, e.g., the HCl salt, wherein R 1 is as defined above, in a suitable organic solvent such as pyridine at a temperature of from about 25° to 100° C. Alternatively, a low molecular weight alcohol (e.g., CH 3 OH or CH 3 CH 2 OH) can be used as the solvent, in which case a base such as sodium acetate must be added. Alternatively, compounds of formula 8 wherein R 1 is not H can be prepared from compounds of formula 8 wherein R 1 is H by deprotonation with a suitable base, preferably NaH or Cs 2 CO 3 , and subsequent treatment with a suitable electrophile such as an alkyl halide, acid chloride or isocyanate.
When R 20 in oxime 8 is a trialkyl silyl hydroxy-protecting group such as (CH 3 ) 3 Si--, (t--Bu)Si(CH 3 ) 2 --, (Et)Si(i-Pr) 2 -- or (i--Pr) 3 Si-- (wherein Et is ethyl, i--Pr is isopropyl and t--Bu is tertiary butyl)), preferably (t--Bu)Si(CH 3 ) 2 --, the oxime can be converted to the corresponding hydroxymethyl oxime of formula 8A, for example by treatment with fluoride ion, preferably TBAF: ##STR16## Oxime 8A can be alkylated, acylated or the hydroxyl group can be activated displaced by sulfur or nitrogen nucleophiles. Alkylations are effected using a base, such as NaH, K 2 CO 3 or Cs 2 CO 3 , in a solvent such as DMF, THF or CH 2 Cl 2 , with an alkylating agent such as an alkyl or benzyl halide or sulfonate. Acylations are effected using an appropriate carboxylic acid in the presence of a dehydrating agent, for example DEC in the presence of HOBT. Nitrogen and sulfur-containing groups can be introduced using Mitsunobu reaction conditions, for example DEAD and PPh 3 in a solvent such as THF with a thiol or amide nucleophile.
Corresponding compounds of formula I wherein A is a ═C(R 11 )(R 12 ) group are prepared by converting a compound of formula 7 to the corresponding alkene of formula 25 ##STR17## by treating the ketone of formula 7 with the Wittig reagent formed from Ph 3 PCHR 11 R 12 R 17 ' (R 17 '=Cl, Br, I) and a suitable base such as NaH, LDA, or R 18 N(TMS) 2 (R 18 =Li, Na, or K) preferably NaN(TMS) 2 , in a suitable organic solvent such as THF or ether, preferably THF, at a temperature from -15° to 65° C. Other suitable reagents for this transformation include the phosphonates (EtO) 2 P(O)CHR 11 R 12 .
Corresponding compounds of formula I wherein A is a ═N--N(R 2 )(R 3 ) group are prepared by converting a compound of formula 7 to the corresponding hydrazone of formula 26 ##STR18## by treating the ketone of formula 7 with a substituted hydrazine of formula H 2 NNR 2 R 3 in a suitable organic solvent such as CH 3 OH or CH 3 CH 2 OH, preferably CH 3 CH 2 OH, in the presence of an acidic catalyst such as acetic acid at a temperature in the range of 0° to 80° C.
Procedure B:
Compounds of formula I wherein R is H, a and d are each 1, X is --O-- or --S--, Q is R 5 -phenyl, T is H, R 4 -aryl, R 4 -cycloalkyl, R 4 -alkyl, R 4 -bicyclo or tricycloalkyl, and the remaining variables are as defined above (see compound 35, below), can be prepared according to the following reaction scheme: ##STR19##
In step 1, the ester (preferably methyl) of the substituted aryl acetic acid of formula 13, wherein R 19 is a lower alkyl group, preferably methyl, is reacted with a compound of formula 14, wherein R 17 ' is as defined above and Pg is a suitable protecting group such as tetrahydropyranyl, and a base to prepare a compound of formula 15. The base can be chosen from any strong base including LDA or lithium bis(trimethylsilyl)amide. The reaction is carried out in an inert organic solvent such as THF at temperatures of -15° to about 65° C.
In step 2, a compound of formula 15 is reacted with an acid in a solvent such as CH 3 OH, at temperatures ranging from -10° to 65° C. The acid need not to be used in stochiometric amount. Alternatively, a compound of formula 16 can be prepared directly from step 1 without isolating the compound of formula 15: the reaction mixture obtained after the work up of the reaction described in step 1 can be dissolved in the solvent and reacted with the acid.
In step 3, a compound of formula 16 is reacted with an acid such hydrobromic acid (HBr) dissolved in a suitable solvent such as acetic acid. The reaction is performed at temperatures ranging from 5° to 45° C.
In step 4, the carboxylic acid of formula 17 is reacted with a halogenating agent such as SOCl 2 or (COCl) 2 in an appropriate solvent such CH 2 Cl 2 to form the acid halide of formula 29.
In step 5, the compound of formula 29 is reacted with an alkylating agent such as diazomethane to obtain the compound of formula 30. This reaction may be performed at temperatures lower than ambient using an appropriate solvent such as Et 2 O.
In step 6, a compound of formula 30 is reacted with a compound of formula 5 (defined above) to obtain a compound of formula 31. The reaction is carried out in a suitable solvent, e.g. EtOAc, at temperatures below 85° C. Bases such as Et 3 N may be beneficial to the reaction.
In step 7, a compound of formula 31 is reacted with a compound of formula 32, wherein X is --O-- or --S--, T is H, R 4 -aryl, R 4 -cycloalkyl, R 4 -alkyl, R 4 -bicyclo or tricycloalkyl, and R 8a , R 9a , b and R 4 is as defined above in an appropriate solvent, e.g. CH 2 Cl 2 , with a Lewis acid, e.g. BF 3 , at temperatures lower than 50° C.
In step 8 a compound of formula 33 is reacted with a compound of formula 34, wherein A is as defined above, in a solvent such as pyridine, to obtain the desired product of formula 35.
Procedure C:
Compounds of formula I wherein R is H, a and d are each 1, A is ═NOR 1 , X is --O--, Q is R 5 -phenyl, T is R 15 -phenyl (R 15 is a subset of R 4 ), and the remaining variables are as defined above (see compound 46, below), can be prepared according to the following reaction scheme: ##STR20##
Steps 1 to 4 are preferably carried out in an inert solvent such as an ether (e.g. Et 2 O, THF, or dioxane) under an inert atmosphere (N 2 or Ar).
In step 1, the anion (Li, Na or K) of ethyl 1,3-dithiolane-2-carboxylate is added to the cinnamate 36 at any suitable temperature, preferably -78° C. to -55° C.
Step 2, deprotection of the carboxy group in 37 is carried out with any suitable reducing agent (e.g. LiAlH 4 or diisobutylaluminum hydride) at any suitable temperature, preferably between 0° C. and 25° C.
In step 3, the hydroxy group of 38 is reacted with t-butyidimethylsilyl chloride and a suitable base (e.g. pyridine, Et 3 N, dimethylaminopyridine, or diisopropylethylamine) at any suitable temperature, preferably between 0° C. and 25° C.
Step 4 is preferably carried out by first adding a suitable base (e.g. KH or (CH 3 ) 3 Si! 2 NK) to the solvent containing 39 and subsequently adding the alkylating agent (e.g. a benzyl chloride or bromide) to obtain 40. Any suitable temperature can be used, preferably between -78° C. and 0° C. for the deprotonation and between 25° C. and 80° C. for the alkylation.
In step 5, removal of the silyl protecting group on 40 is preferably carried out with a fluoride source such as HF in CH 3 CN or tetrabutyl-ammonium fluoride in an inert solvent such as an ether as described above. This step can also be carried out with acid (e.g. HOAc, CF 3 CO 2 H, tosic acid, H 2 SO 4 , or HCI) and water in an inert solvent such as an ether as described above, or in a chlorinated hydrocarbon (e.g. CH 2 Cl 2 , 1,2-dichloroethane, or CHCl 3 ). Any suitable temperature can be used, preferably temperatures between 0° C. and 80° C.
In step 6, oxidation of the dithiolanyl ring of 41 is preferably carried out with an oxidizing agent such as HgClO 4 , AgNO 3 , Ag 2 o, copper chloride with copper oxide, thallium nitrate, N-chlorosuccinimide, or N-bromosuccinimide in an inert solvent such as an ether (e.g. Et 2 O, THF, or dioxane), CH 3 COCH 3 , or CH 3 CN. Any suitable temperature can be used with preferable temperatures between 0° C. and 80° C. Compounds 42 and 43 are present in equilibrium.
Preparation of the oxime of formula 44 in step 7 is preferably carried out on the mixture of 42 and 43 with a suitably substituted hydroxylamine (as its acid salt e.g. HCl or maleate, or as its free base) and a suitable base such as sodium acetate or pyridine in a protic solvent (e.g. water, CH 3 OH, CH 3 CH 2 OH, or isopropanol). Any suitable temperature can be used, with preferable temperatures between 25° C. and 100° C.
In step 8, preferably 44 is treated with a suitable oxidizing agent (e.g. pyridinium chlorochromate, chromium trioxide-pyridine, pyridinium dichromate, oxalyl chloride-dimethylsulfoxide, acetic anhydride-dimethylsulfoxide, or periodinane) in an inert solvent such as chlorinated hydrocarbons (e.g. CH 2 Cl 2 , 1,2-dichloroethane, or CHCl 3 ) to obtain the ketone 45. Any suitable temperature can be used with preferable temperatures between -78° C. and 25° C.
Step 9 is preferably carried out with a suitably substituted amine (as its acid salt e.g. HCl or maleate or as its free base) and a hydride source such as NaBH 3 CN or sodium triacetoxyborohydride in a protic solvent (e.g. CH 3 OH, CH 3 CH 2 OH, or CF 3 CH 2 OH) with 3A sieves to obtain 46. Any suitable temperature can be used with preferable temperatures between 0° C. and 25° C.
Procedure D:
Compounds of formula I as defined above can be prepared as shown in the following reaction scheme: ##STR21##
In step 1, a compound of formula 47A. wherein Q is as defined above, is reacted with a base such as lithium disopropylamide (LDA) or KH in an inert organic solvent such at THF or DME to generate a dianion. An acid chloride, ester or amide of formula 46A, 46B, or 46C is added to give a ketone of formula 48. Preferable reaction temperatures ranges from -78° C. to 30° C.
Alternatively, compounds of formula 48 can be generated by the reaction of a compound of formula 46, preferably 46C, with a metallated species of formula QCH 2 Mt where Mt is a metal, such as MgHal, wherein "Hal" is halogen, or lithium. The metallated species QCH 2 Mt can be generated by conventional procedures, such as treatment compounds of formula QCH 2 Hal with Mg or by treating QCH 3 with an organolithium base. ##STR22##
In step 2, for compounds of formula I wherein R is not hydrogen, the ketone 48 is reacted with a suitable base, such as LDA or KH in an inert organic solvent such as THF. For compounds wherein R is alkyl or hydroxyalkyl, a compound R--R 17 ", wherein R 17 " is leaving group such as Br, I or triflate is added. For compounds wherein R is OH, an appropriate oxidizing agent such as dimethyldioxirane or Davis reagent is added. Preferable reaction temperatures range from -78° to 50° C. ##STR23##
In step 3, ketone 49 is reacted with a base such as LDA in a solvent such as THF, then an olefin of formula 50 is added, wherein R 17 " is as defined above, to give the adduct 51. Preferable reaction temperatures range from -78° C. to 60° C. ##STR24##
In step 4, ketone 51 is reacted with HA', wherein A' is NH--OR 1 , NH-N(R 2 )(R 3 ) or NHR26, in an organic solvent such as pyridine at a temperature from 25° C. to 150° C. to give a compound of formula 52. ##STR25##
In step 5, a compound of formula 52 is oxidized by ozonolysis to give an aldehyde of formula 53. Suitable organic solvents include EtOAc, ethanol or the like. Preferable reaction temperatures are from -78° to 0° ##STR26##
In step 6, an aidehyde of formula 53 is reacted with a compound of formula Z-H, wherein Z is as defined above, as described in Step 9 of Procedure C.
Alternatively, a compound of formula I can be prepared from 51 by the following reaction scheme: ##STR27##
Compound 51 is oxized to a compound of formula 54 under conditions similar to those described for step 5 above. The aldehyde of formula 54 is reacted with a compound of formula Z--H in a manner similar to that described in Step 6, and the resultant ketone is then reacted with a compound of the formula HA' as described above in Step 4 to obtain the compound of formula I.
Procedure E:
Compounds of formula I wherein X is --O-- or a bond and d is 1 or 2 can be prepared by the following reaction scheme, starting with ketone 49 from Procedure D. Alternatively, compounds of formula 49 can be prepared from compounds of formula 46D, wherein X is --O--, R 6a and R 7a are each H, and d is 1, which, in turn, are prepared according to the following reaction scheme: ##STR28## wherein compounds of formula 55, wherein R 21 is alkoxy or --N(CH 3 )OCH 3 and R 17 ' is as defined above are reacted with alcohols of the formula HO--(C(R 8a )(R 9a )) b --T in the presence of a suitable base such as Cs 2 CO 3 or KHMDS to give the desired ether 46D. ##STR29##
In step 1, compounds of formula 49 treated with an appropriate base, such as NaH, are reacted with alkylating agents of the formula R 33 C(O)CH 2 R 17 or R 33 C(O)CH═CH 2 wherein R 33 is alkoxy or --N(CH 3 )OCH 3 and R 17 is as defined above. ##STR30##
In step 2, compounds of formula 56 can be converted to the corresponding oxime of formula 57 in a manner similar to that described in Procedure D, Step 4. ##STR31##
In step 3, compounds of formula 57 (or 56, i.e., wherein A' is O) are converted to the corresponding aldehyde 58 (or lactol from the keto-ester 56) by treatment with a suitable reducing agent such a DIBAL, in an suitable inert organic solvent such as THF, at a temperature from about -100° to -20° C. ##STR32##
In step 4, compound 58 is reacted with an amine ZH in a manner similar to that described in Procedure B, Step 9, to obtain the compound of formula I.
Alternatively, as shown in the following reaction scheme, compounds of the formula 59, wherein R is H, A' is ═O, X is --O-- and R 33 is alkoxy can be converted to the corresponding lactol of formula 60 by treatment with a suitable reducing agent such a DIBAL, in an suitable inert organic solvent such as THF, at a temperature from about --100°0 to --20° C.: ##STR33##
The lactol is then reacted with an amine ZH as described in Procedure A, Step 4, to give the amino alcohol 6.
Procedure F:
Compounds of formula I wherein R is H, d is 1, R 6a and R 7a are each H, X is a bond, --(C(R 9a )(R 8a )) b -- is --CH(OH)(C(R 8a )(R 9a )) b1 --, wherein b1 is 0 or 1 and R 8a and R 9a are generally as defined above, but are preferably not R 15 -phenyl or R 15 -benzyl, and the remaining variables are as defined above, are prepared by the following procedure (In the scheme below, Z is exemplified by 4-hydroxy-4-phenylpiperidine, but other Z--H amines can also be used.): ##STR34##
In Step 1, the amine of formula63 is condensed with the acid of formula 64 using standard methods, for example a coupling agent such as DCC or EDCI in the presence of a base such as pyridine or Et 3 N (when necessary) is used in a solvent such as THF at temperatures from 0 to 50° C. preferably room temperature.
In Step 2, the alkene of formula 65 is converted to the nitro-substituted compound of formula 66 by refluxing the alkene in nitromethane in the presence of a base such as an alkoxide, a tert.-ammonium hydroxide or alkoxide, a trialkyl amine or a metal fluoride salt. The nitromethane can act as the solvent, or another solvent such as an alcohol, an ether, DMSO or DMF also can be used.
In Step 3, the nitro-oxobutyl compound of formula 66 is reacted with the olefin of formula 67 and C 6 H 5 NCO in the presence of a trace amount of a base such as Et 3 N, in an inert, non-hydroxylic solvent such as THF or CH 2 Cl 2 to obtain the isoxazolinyl compound of formula 68. Reaction temperatures range from 0 to 40° C., with room temperature preferred.
In Step 4, the keto group is reduced, for example by refluxing with a reagent such as borane-dimethylsulfide complex. In Step 5, the isoxazolinyl ring is opened by treatment with Raney Nickel under conditions well known in the art. In Step 6, the ketone is converted to the oxime as described in Procedure A, Step 6.
The hydroxy-substituted compounds prepared above can be oxidized to the corresponding ketones, for example by treatment with Jones reagent. The resultant ketones can be converted to the corresponding bis-oximes using the methods described in Procedure A, Step 6.
Procedure G:
Compounds of formula I wherein R is H, d is 0, X is --C(O)-- and the remaining variables are as defined above, are prepared by the following procedure (As above, other Z--H amines can also be used.): ##STR35##
In Step 1, a compound of formula 66 is reduced in a manner similar to Procedure F, Step 4. In Step 2, the resultant nitrobutyl compound of formula 71 is reacted with a carboxyl derivative of formula 72, wherein R 34 is a leaving group such a phenoxy, or an activating group such as p-nitro-phenyl, imidazolyl or halogeno, in the presence of a base such as potassium tert.-butoxide, in a solvent such as DMSO. Reaction temperatures range from 0° to 30° C.
In Step 3, the nitro group is converted to the oxime by treatment with CS 2 in the presence of a base such as Et 3 N in a solvent such as CH 3 CN. The oxime can be converted into other oximes of formula I, i.e., wherein A is ═N--OR 1 and R 1 is other than H, by the methods described in Procedure A, Step 6.
Similarly, compounds of formula I wherein d is 0, X is a bond, --(C(R 9a )(R 8a )) b -- is --CH(OH)CH 2 -- and the remaining variables are as defined above, are prepared by reducing the keto group of compound 73 using well known techniques, for example by treatment with NaBH 4 , followed by converting the nitro group to the oxime as described above.
Procedure H:
Compounds of formula I wherein R is H, d is 0, X is --NH--, A is ═NH, --(C(R 9a )(R 8a )) b --T is --(CH 2 ) b2 --T--, wherein b2 is 1 or 2 and the remaining variables are as defined above, are prepared by the following procedure (As above, other Z--H amines can also be used.): ##STR36##
In Step 1, the nitrobutyl compound of formula 71 is reduced to the corresponding nitrile by treatment with CS 2 in the presence of a base such as Et 3 N in a solvent such as CH 3 CN at temperatures of 20° to 70° C.
In Step 2, the nitrile of formula 74 is reacted at elevated temperatures with an amine of formula NH 2 --(CH 2 ) b2 --T in the presence of a catalyst such as a trialkylaluminum, in a solvent such as CH 2 Cl 2 or toluene.
The following procedure can be used to prepare similar compounds wherein --(C(R 9a )(R 8a )) b -- is --CH 2 (C(R 9a )(R 8a ))-- and A is ═NOR 1 : ##STR37##
In Step 1, a oximeamide of formula 75, prepared by treating a compound of formula 74 with hydroxylamine, is reacted with a carbonyl derivative of formula 72 in a solvent such as pyridine at a temperature of about 70° C. to obtain an oxadiazolyl compound of formula 76.
In Step 2, the oxadiazolyl ring is opened by treatment with a reducing agent such as LAH, in a solvent such as ether, at temperatures of 20° to 60° C. to obtain the desired compounds of formula I.
Preparation of Starting Materials:
Starting materials of formula 27 ##STR38## wherein X is --NR 6 -- or --S-- and Z, R 4 , R 5 , R 6a and R 7a are as defined above can be prepared as shown in the following reaction scheme: ##STR39## In step 1, compound 1, wherein R 5 is as defined above, is treated with a halogenating agent such as I 2 or N-bromosuccinimide in an organic solvent such as CH 3 CN, THF or DMF at a temperature in the range of 0 to 250° C. to give the halolactone 9. ##STR40## In step 2, compound 9 is dissolved in an alcohol R 22 OH wherein R 22 is a lower alkyl group such as methyl or ethyl, preferably methyl. A base such as Cs 2 CO 3 or Na 2 CO 3 is added and the mixture stirred at a temperature range of 0° to 50° C. to give the epoxide 10.
Alternatively, a lower alkyl ester of 1 can be epoxidized by a suitable epoxidizing agent such as dimethyl dioxirane or m-CPBA to obtain a compound of formula 10. ##STR41## In step 3, a solution of epoxide 10 in an alcohol such as CH 3 OH, CH 3 CH 2 OH, or more preferably CF 3 CH 2 OH, is treated with a nucleophile of the formula ##STR42## wherein X is --NR 6 -- or --S--, and R 4 is as defined above, at 0° to 90° C. to give the lactone 11. Step 4: Using the reactions of Procedure A, steps 3 and 4, convert the lactone of formula 11 to the desired product of formula 27.
In a similar manner, starting materials of formula 28 ##STR43## wherein X is --NR 6 -- and T, Z, R 5 , R 6a and R 7a are as defined above can be prepared as described above by treating an epoxide of formula 10 with an amine of formula HN(R 6 )--T and converting the resultant lactone to the compound of formula 28.
Also in a similar manner, an epoxide of formula 10 can be treated with a thiol of formula HS(C(R 8a )(R 9a )) b --T to obtain the corresonding lactone, which can be converted to the desired compound using Procedure A, steps 3 and 4. Sulfides can be converted to the sulfoxides and sulfones by oxidation with suitable reagents such as m-CPBA or potassium peroxymonosulfate.
Diol starting materials of formula 21 ##STR44## wherein Z and R 5 are as defined above, can be prepared as shown in the following reaction scheme: ##STR45## In step 1, compound 1 is dissolved in an inert organic solvent such as CH 2 Cl 2 or toluene, preferably CH 2 Cl 2 , and treated with a reagent such as (COCl) 2 , SOCl 2 or PCl 3 , most preferably (COCl) 2 , in the presence of a catalytic amount of DMF and at temperatures from 0° to 75° C. to give compound 18. ##STR46## In step 2, compound 18 is dissolved in pyridine at room temperature and treated with an amine of formula 5 as defined above, to give the compound 19. Alternatively, compound 18 is dissolved in an inert organic solvent such as CH 2 Cl 2 or toluene, preferably CH 2 Cl 2 , the mixture is cooled to 0° C. and a tertiary amine base such as Et 3 N or (CH 3 ) 3 N is added, followed by an amine 5.; the reaction is allowed to warm to room temperature to give the product 19. Other coupling methods known to those skilled in the art, such as EDC coupling, may also be employed. ##STR47## In step 3, the amide 19 is converted to the corresponding amine by standard reduction procedures, for example, it is taken up in an inert organic solvent and treated with a reducing agent at 0° to 80° C. to give the amine 20. Suitable solvents include ether, THF, CH 2 Cl 2 and toluene, preferably THF. Reducing agents include LAH, BH 3 ·Me 2 S and DiBAL-H, preferably LAH. ##STR48## In step 4, the amine 20 is converted to the diol 21 by standard dihydroxylation procedures, for example, it is dissolved in a mixture of acetone and water at room temperature and treated with NMO and OsO 4 .
Intermediate furanones for use in Procedure A, for example those of formula 62, can be prepared as follows: ##STR49## A furanone of formula 61 undergoes conjugate addition with a variety of nucleophiles, e.g., thiolates, azides and aryl anions to obtain compounds of formula 62. For example, compounds of formula 62 wherein Q is phenyl is prepared by treating 61 with phenyllithium in the presence of CuCN and (CH 3 ) 3 SiCl.
In the above procedures, T and Q generally are exemplified as R 5 -phenyl and R 4 -phenyl, respectively, but those skilled in the art will recognize that in many cases, similar procedures can be used to prepare compounds wherein T and Q are other than substituted-phenyl.
Reactive groups not involved in the above processes can be protected during the reactions with conventional protecting groups which can be removed by standard procedures after the reaction. The following Table 1 shows some typical protecting groups:
TABLE 1______________________________________Groupto beProtected Group to be Protected and Protecting Group______________________________________COOH COOalkyl, COObenzyl, COOphenyl ##STR50## ##STR51## ##STR52## ##STR53##NH.sub.2 ##STR54##OH ##STR55## or OCH.sub.2 phenyl______________________________________
Compounds of formula I have been found to be antagonists of NK 1 and/or NK 2 and/or NK 3 receptors, and are therefore useful in treating conditions caused or aggravated by the activity of said receptors.
The present invention also relates to a pharmaceutical composition comprising a compound of formula I and a pharmaceutically acceptable carrier. Compounds of this invention can be administered in conventional oral dosage forms such as capsules, tablets, powders, cachets, suspensions or solutions, or in injectable dosage forms such as solutions, suspensions, or powders for reconstitution The pharmaceutical compositions can be prepared with conventional excipients and additives, using well known pharmaceutical formulation techniques. Pharmaceutically acceptable excipients and additives include non-toxic and chemically compatibile fillers, binders, disintegrants, buffers, preservatives, anti-oxidants, lubricants, flavorings, thickeners, coloring agents, emulsifiers and the like.
The daily dose of a compound of formula I for treating asthma, cough, bronchspasm, inflammatory diseases, migraine, nociception and gastrointestinal disorders is about 0.1 mg to about 20 mg/kg of body weight per day, preferably about 0.5 to about 15 mg/kg. For an average body weight of 70 kg, the dosage range is therefore from about 1 to about 1500 mg of drug per day, preferably about 50 to about 200 mg, more preferably about 50 to about 500 mg/kg per day, given in a single dose or 2-4 divided doses. The exact dose, however, is determined by the attending clinician and is dependent on the potency of the compound administered, the age, weight, condition and response of the patient.
Following are examples of preparing starting materials and compounds of formula I. As used herein, Me is methyl, Bu is butyl, Br is bromo, Ac is acetyl, Et is ethyl and Ph is phenyl.
PREPARATION 1
α- (3.5-bis(trifluoromethyl)phenyl!methoxy!methyl!-β-(3.4-dichlorophenyl)-4-hydroxy-4-phenyl 1-piperidinebutanol ##STR56## Step 1: Cool a solution of 3-(3,4-dichlorophenyl)-2-propeneoic acid (100 g, 461 mmol) in dry DMF (500 mL) to 0° C. and treat with Cs 2 CO 3 (100 g, 307 mmol, 0.66 eq). Stir the resulting off-white slurry for 15 min, then add CH 3 l (33 mL, 530 mmol, 1.15 eq) via syringe. After 1 h, add additional DMF (250 mL), stir the slurry for 14 h and partition between EtOAc (1.5 L) and half saturated aqueous NaHCO 3 (500 mL). Separate the organic layer and extract the aqueous layer twice with EtOAc (1 L, 500 mL). Wash the combined organic layers with half saturated aqueous NaHCO 3 (500 mL) and water (5×500 mL), then dry (Na 2 SO 4 ) and concentrate to obtain 105.4 g (456 mmol, 99%) of methyl 3-(3,4-dichlorophenyl)-2-propenoate as light brown needles.
Step 2: Treat a solution of the product of Step 1 (15 g, 65 mmol) in dry THF (250 mL), kept cool in a large ambient temperature water bath, with Dibal-H (140 mL, 140 mmol, 2.15 eq) over 30 min. Stir the resulting solution for 30 min at 23° C., pour into Et 2 O (500 mL), treat with water (5 mL), 15% NaOH (5 mL) and water (15 mL). Stir for 5 min, dilute the mixture with Et 2 O (200 mL) and treat with 15% NaOH (15 mL). Add MgSO 4 to cause a colorless precipitate. Remove the aluminum salts by filtration through a course glass frit. Wash the solids with Et 2 O (1 L) and concentrate the filtrate in vacuo to give 13.2 g (65 mmol, 99%) of 3-(3,4-dichlorophenyl)-2-propene-1-ol as an off-white solid.
Step 3: Treat a solution of the product of step 2 (13.2 g, 65 mmol) in CH 2 Cl 2 (250 mL) at 0° C. with pyridine (7.89 mL, 97.5 mmol, 1.5 eq) and dimethylaminopyridine (397 mg, 3.25 0.05 eq), followed by CH 3 COCl (6.48 mL, 74.75 mmol, 1.15 eq). Allow the mixture to warm to 23° C., pour into 1M HCl (100 mL) and wash the resulting organic layer again with 1 M HCl (100 mL), followed by water (5×100 mL; pH═6.5-7). Dry the organic layer (Na 2 SO 4 ) and concentrate to obtain 15.4 g (62.9 mmol, 97%) of 3-(3,4-dichlorophenyl)-2-propene-1-ol acetate as a colorless oil.
Step 4: Treat a solution of the product of step 3 (15 g, 61 mmol, dried by azeotropic distillation with toluene, 1×50 mL) in dry THF (250 mL) at -78° C. with chlorotriethylsilane (20.2 mL, 120 mmol, 2.0 eq) rapidly followed by the addition of potassium bis(trimethylsilyl)amide (183 mL, 91.5 mmol, 1.5 eq of 0.5M in toluene) via addition funnel over 50 min. Allow the mixture to warm to 23° C. and heat to reflux for 3 h. Gradually cool the solution overnight, then quench with saturated NH 4 Cl (150 mL). Stir the resultant mixture vigorously for 3h, treat with 1M HCl (150 mL) and then extract with Et 2 O (500 mL). Extract the aqueous layer with Et 2 O (400 mL), wash the combined organic layers with 5% NaOH (300 mL) and extract with 5% NaOH (8×150 mL). Cool the combined aqueous layers to 5° C. and, maintaining the temperature at 5°-10° C., acidify with conc. HCl (ca 175 mL) to pH 1. Extract the aqueous layer with CH 2 Cl 2 (2×800 mL), dry (Na 2 SO 4 ) and concentrate to give 13.4 g (54.5 mmol, 89%) of 3-(3,4-dichlorophenyl)-4-pentenoic acid as a faint yellow oil.
Step 5: Treat a solution of the product of step 4 (5.0 g, 20.4 mmol) in dry CH 2 Cl 2 (60 mL) with purified m-CPBA (7 g, 40 mmol, 2 eq) wash 13 g of commercial 55% mCPBA in 250 mL of benzene with pH 7.4 buffer (5×30 mL), dry (Na 2 SO 4 ) and concentrate to obtain about 9 g of pure m-CPBA!. Stir for 48 h, add Amberlyst 15 (1.2 g) and stir the mixture for 8 h. Remove the Amberlyst by filtration through a medium porosity glass frit, rinsing with EtOAc. Wash the filtrate with saturated Na 2 SO 3 :NaHCO 3 (1:1) (100 mL). Dry the resulting organic layer and concentrate in vacuo. Take up the crude resulting product in hexahe:CH 2 Cl 2 (1:1) and filter to give 3.3 g (12.6 mmol, 62%) of a mixture of isomers (3:2, trans/cis) of 4-(3,4-dichlorophenyl)-dihydro-5-(hydroxymethyl) 2(3H)-furanone as a colorless soft solid. Concentrate the filtrate to give 2.0 g of a viscous oil. Purify the oil by silica gel chromatography (column: 7×15 cm; solvent: hexane:EtOAc, 5:4 gradient to 1:1) to give 1.07 g (4.1 mmol, 20%) of the pure cis isomer as an oil to give a total yield of 4.3 g (16.47 mmol, 81%).
Step 6: Treat a solution of the product of step 5 (3.3 g, 12.6 mmol, 3:2 ratio of stereoisomers by NMR) in dry DMF(10 mL) with 3,5-bistrifluoro-methylbenzyl bromide (5.9 mL, 32.2 mmol, 2.5 eq) followed by Ag 2 O (5.8 g, 25.3 mmol, 2 eq), wrap the vessel in foil and stir for 2.5 days. Apply the resultant crude material to a pad of silica gel (10 cm×4 cm) packed with hexane:EtOAc (1:1). Wash the pad with the same solvent until no further product is eluted as shown by TLC and concentrate the resulting filtrate in vacuo to give the crude product as a solid (10 g). Dissolve the resultant residue in hexane:EtOAc (4:1) and purify by silica gel chromatography (column: 7.5×19; solvent: hexane:EtOAc (4:1)) to give 3.33 g (6.8 mmol, 54%) of (trans)- (3,5-bis(trifluoromethyl)phenyl!methoxy!methyl!-4-(3,4-dichlorophenyl)-dihydro-2(3H)-furanone and 1.08 g (2.2 mmol, 17%) of the corresponding cis isomer for a total yield of 71%. Trans isomer: HRMS (FAB, M+H + ): m/e calc'd for C 20 H 15 O 3 Cl 2 F 6 ! + : 487.0302, found 487.0312.Cis isomer: HRMS (FAB, M+H + ): m/e calc'd for C 20 H 15 O 3 Cl 2 F 6 ! + : 487.0302, found 487.0297.
Step 7: Cool a solution of the cis isomer of the product of step 6 (2.1 g, 4.31 mmol) in dry CH 2 Cl 2 (50 mL) to -78° C. and treat with Dibal-H (5.1 mL, 5.1 mmol, 1.2 eq; 1M in CH 2 Cl 2 ). Stir for 2 h at -78° C., then treat the solution with NaF (905 mg, 22 mmol, 5 eq) and water (400 μL, 22 mmol, 5 eq). Allow the suspension to warm to 23° C. and stir for 45 min. Dilute the mixture with Et 2 O (50 mL) and filter through a pad of silica gel (6.5 cm×2 cm; 150 mL vacuum glass frit) packed with hexane:EtOAc (1:1). Wash the pad with hexane:EtOAc (1:1) until no further product is evident by TLC (ca. 600 mL). Concentrate the filtrate to give 1.92 g (3.86 mmol, 91%) of (cis)- (3,5-bis(trifluoromethyl)phenyl!methoxy!methyl!-4-(3,4-dichlorophenyl)-tetrahydro-2-furanol as a foam which is used without further purification.
Step 8: Treat a solution of the product of step 7 (1.92 g, 3.86 mmol) in 2,2,2 trifluoroethanol (10 mL) with powdered 3Å MS (3.5 g) followed by 4-hydroxy-4-phenylpiperidine. Stir the resulting suspension under N 2 for 1 h at 23° C., then add NaCNBH 3 (533 mg, 8.6 mmol, 2 eq) and stir for 20 h. Filter the resultant mixture through a pad of silica gel (9.5 cm×2.5 cm, 600 mL, vacuum glass frit) packed and eluted with EtOAc:triethylamine (9:1) (ca. 500 mL) until no further product is apparent by TLC. Remove the solvent to obtain 2.77 g (>90%) of the title compound as a colorless foam. HRMS (FAB, M+Na + ): m/e calc'd for C 31 H 32 NO 3 Cl 2 F 6 ! + : 650.1663, found 650.1647.
Preparation 2 ##STR57##
Using the trans isomer of Preparation 1, step 6, carry out the procedure of Preparation 1, steps 7-8 to obtain the title compound. HRMS (FAB, M+H + ): m/e calc'd for C 31 H 32 NO 3 Cl 2 F 6 ! + : 650.1663, found 25 650.1654.
Preparation 3 ##STR58## Steps 1-2: Treat a solution of the product of Preparation 1, step 4 (1.6 g, 6.5 mmol) in dry benzene (15 mL) at 5° C. with ClCOCOCl (680 μL, 7.8 mmol, 1.2 eq) followed by DMF (10 μL). Stir the resulting solution for 3 h at 23° C., concentrate in vacuo, azeotrope with benzene (1×15 mL), dissolve in dry CH 2 Cl 2 (15 mL) and cool to 0° C. Treat a solution of 4-hydroxy-4-phenyl piperidine (2.3 g, 13 mmol, 2 eq) in dry CH 2 Cl 2 (20 mL) with pyridine (1.57 mL, 19.5 mmol, 3 eq) and cool to 0° C. Add the acid chloride via cannula over a period of 20 min. Stir the resulting solution for 15 min, warm to 23° C., dilute with CH 2 Cl 2 (150 mL) and wash consecutively with 10% aqueous citric acid (2×50 mL), water (1×50 mL) and aqueous saturated NaHCO 3 (1×50 mL), dry (Na 2 SO 4 ) and concentrate. Purify the crude product by silica gel chromatography (column: 7×14 cm; eluant: hexane/EtOAc (1:1) (1 L) gradient to hexane/EtOAc (3:5) (2 L)) to provide 1.995 g (494 mmol, 76%) of the desired amide as a colorless solid.
Step 3: Treat a solution of the amide from step 2 (4.1 1g, 10.2 mmol) in dry THF (50 mL) with LiAlH 4 (20.4 mL of 1M solution in ether, 20.4 mmol, 2 eq). Stir for 30 min at 23° C., then pour the mixture into Et 2 O (300 mL) and treat with water (750 μL), then 15% NaOH (750 μL) followed by water (3 mL). Remove the resulting aluminum salts by filtration through a glass frit, concentrate the filtrate, dissolve in hexane/EtOAc/triethyl amine (49:49:2) and filter through a plug of silica gel (10×4 cm), eluting with 800 mL of solvent. Concentrate the filtrate to give 3.38 g (8.67 mmol, 85%) of the desired amine as a yellow oil.
Step 4: Treat a solution of the product of step 3 (3.0 g, 7.69 mmol) in acetone/water (15 mL /30 mL) with NMO (1.35 g, 11.5 mmol, 1.5 eq) followed by OSO 4 (3.9 mL of 2.5% w/w solution in t-butanol, 0.38 mmol, 0.05 eq). After stirring for 17 h, treat the mixture with saturated aqueous Na 2 SO 3 (100 mL) and stir for 1 h. Concentrate the mixture in vacuo, extract the resulting aqueous solution with CH 2 Cl 2 (3×100 mL), dry the resulting organic layer (Na 2 SO 4 ) and concentrate. Purify the crude product by silica gel chromatography (7×20 cm; eluant: gradient: CH 2 Cl 2/ CH 3 OH/triethylamine (180:5:150) to (140:5:50) to (100:5:150) to (10:1:1) to obtain 932 mg (2.19 mmol, 29%) of the trans diol as light amber oil and 1.455 g (3.4 mmol, 45%) if the cis diol as a colored oil. Pool mixed fractions to obtain an additional 221 mg of product as a mixture of isomers, giving a total yield of 6.11 mmol, 80%.
HRMS (FAB, M+H + ): m/e calc'd for C 22 H 28 Cl 2 NO 3 ! + : 424.1446, found 424.1435.
Preparation 4
1 (3.5-bis(trifluoromethyl)phenyl!methoxy!-3-(3,4-dichlorophenyl)-5-(4-hydroxy-4-phenyl-1 -piperidinyl)-2-pentanone ##STR59##
Treat a solution of the product of Preparation 1 (2.0 g, 3.08 mmol) in acetone (90 mL, 0° C.) with Jones reagent (9 mL of H 2 CrO 4 in H 2 SO 4 (ca. 8M)). Stir the light orange suspension at 0° C. for 1 h, then partition between CH 2 Cl 2 (150 mL) and saturated aqueous NaHCO 3 (150 mL). Extract the aqueous layer with CH 2 Cl 2 (3×150 mL), back extract the combined organic layers with saturated aqueous NaHCO 3 (150 mL), dry (Na 2 SO 4 ) and concentrate to give 1.94 g crude product. Purify by silica gel chromatography (column: 4 cm×15 cm; eluant: EtOAc:hexane: triethylamine (66:33:2)) to obtain 1.64 g (2.53 mmol, 82%) of the title compound as a colorless foam.
HRMS (FAB, M+H + ): m/e calc'd for C 31 H 30 NO 3 Cl 2 F 6 ! + : 648.1507, found 648.1496.
Preparation 5
β-(3,4-dichlorophenyl)-4-hydroxy-α- (methylphenylamino)methyl !-4-phenyl-1-piperidinebutanol ##STR60##
Step 1: Cool a solution of the product of Preparation 1, step 4 (6.4 g, 26 mmol) in dry CH 3 CN to 0° C. and treat with I 2 (19.8 g, 78 mmol, 3 eq). Store the solution at 0° C. for 100 h, then pour into saturated aqueous NaHCO 3 (250 mL)/saturated aqueous Na 2 SO 3 (100 mL)/Et 2 O (400 mL). Extract the aqueous layer with Et 2 O (200 mL) and wash the combined Et 2 O layers with a mixture of saturated aqueous Na 2 SO 3 (25 mL) and brine (100 mL). Dry the organic layer over MgSO 4 and concentrate to give a light yellow solid. Purify the crude material by recrystallization (hot isopropanol, 2×) to obtain 7.42 g (19.9 mmol, 77%) of 4-(3,4-dichloro-phenyl)-dihydro-5-(iodomethyl)-2(3H)-furanone as an off-white solid.
Step 2: Treat a solution of the product of step 1 (1.5 g, 4.02 mmol) in dry CH 3 OH (15 mL) under N 2 with Cs 2 CO 3 (1.57 g, 4.8 mmol, 1.2 eq). Stir for 30 min, then pour the suspension into Et 2 O (200 mL)/water (100 mL). Extract the aqueous layer with Et 2 O (100 mL), wash the combined ether layers with 40 mL of saturated NaCl, dry (MgSO 4 ), and concentrate to give 1.11 g (4.02 mmol,>99%) of methyl β-(3,4-dichlorophenyl)-oxiranepropanoate as a colorless oil.
Step 3: Treat a solution of the product of step 2 (368 mg, 1.34 mmol) in 2,2,2 trifluoroethanol (1 mL) with N-methyl aniline (217 μL, 2.01 mmol, 1.5 eq) and stir for 6 h at 23° C. followed by 6 h at 80° C. Cool to 23° C., concentrate in vacuo and purify by silica gel chromatography (column: 3.5×12 cm; eluant: hexane:EtOAc (4:1)) to provide 446 mg (1.3 mmol, 97%) of 4-(3,4-dichlorophenyl)-dihydro-5- (methylphenylamino)methyl!-2(3H)-furanone as a white solid.
Step 4: Cool a solution of the product of step 3 (435 mg, 1.24 mmol) in dry CH 2 Cl 2 (10 mL) to -78° C. and treat with Dibal-H (1.56 mL, 1M in CH 2 Cl 2 ). Stir the solution for 2 h, then add NaF (273 mg, 6.5 mmol, 5 eq) and water (117 μL, 6.5 mmol, 5 eq). Dilute the mixture with Et 2 O (100 mL) and warm to 23° C. Treat the mixture with MgSO 4 , stir for 10 min, filter through a sintered glass frit and concentrate. Take up the residue in hexane:EtOAc (1:1) and filter through a pad of silica gel (7×2 cm) with about 150 mL of hexane:EtOAc (1:1). Concentrate the filtrate to obtain 415 mg (1.17 mmol, 95%) of the desired lactol as a colorless film.
Step 5: Treat a solution of the product of step 4 (415 mg, 1.17 mmol) in 2,2,2 trifluoroethanol with 4-hydroxy-4-phenyl piperidine (450 mg, 2.54 mmol, 2 eq) and 3Å MS (1 g). Stir for 2h, treat the mixture with NaCNBH 3 (157 mg, 2.54 mmol, 2 eq) and stir the resulting suspension vigorously for 16 h. Evaporate the solvent in vacuo, take up the crude in EtOAc, apply to a silica gel column (3.5×12 cm) packed with hexane:EtOAc:triethylamine (66:33:2) and elute with gradient elution: EtOAc:triethyl amine (98:2) to EtOAc:CH 3 OH:triethylamine (80:20:2), to obtain 569 mg (1.1 1 mmol, 95%) of the title compound as a colorless foam.
HRMS (FAB, M+H + ): m/e calc'd for C 29 H 35 N 2 O 2 Cl 2 ! + : 513.2076, found 513.2063.
Compounds of Preparations 5A to 5C are prepared in a similar manner, using the appropriate amines in step
______________________________________ ##STR61## HRMS calc'd (FAB, HRMSPrep.T Amine M + H.sup.+) Found______________________________________5A ##STR62## N-methyl- (3,5-bistri- fluoromethyl- phenyl) benzyl amine 633.1980 633.19955B ##STR63## N-methyl benzyl amine 527.2232 527.22465C ##STR64## N-methyl-(3- isopropoxy) benzyl amine 585.2651 585.2644______________________________________
Preparation 6
Substituted Piperidines--Method A ##STR65##
Dissolve 4-aminomethyl-piperidine (30.00 g, 0.263 mol) in CH 3 OH (500 mL), cool to -30° C. under N 2 , add di-t-butyl dicarbonate (38.23 g, 0.175 mol) in CH 3 OH (100 mL) dropwise, warm slowly to 23° C. and stir for 16 h. Concentrate, add CH 2 Cl 2 (700 mL), wash with saturated aqueous NaCl (2×200 mL), dry organic solution (MgSO 4 ), filter and concentrate to give 36.80 g of a 86:14 mixture of the title compound and 1,1-dimethyl-ethyl 4- (1,1-dimethylethyloxycarbonyl)methyl!-1-piperidinecarboxylate. ##STR66##
Dissolve the product (19.64 g, 0.0916 mol, 22.84 g of the mixture) of Step 1 in dry CH 2 Cl 2 (350 mL) and cool to 0° C. under N 2 . Add pyridine (10.87 g, 11.1 mL, 0.137 mol) then chlorovaleryl chloride (15.63 g, 13.0 mL, 0.101 mol), warm slowly to 23° C. and stir for 16 h. Add saturated aqueous NH 4 Cl (300 mL), separate layers and extract with CH 2 Cl 2 (2×250 mL). Dry combined organic extracts (MgSO 4 ), filter and concentrate. Purify by chromatography (1000 mL of flash silica gel; eluant: 1:1 EtOAc:hexane, then EtOAc). Combine appropriate fractions and concentrate to give 25.36 g (0.0762 mol. 84%) as a colorless oil.
MS (Cl/CH 4 ): m/e 333 (M+1) ##STR67##
Treat the product of Step 1 in a procedure similar to that described for Step. 2A, using chlorobutryl chloride. MS (FAB): m/e 319 (M+1) ##STR68##
Wash NaH (3.84 g, 0.160 mol, 6.40 g of 60 wt %) with hexane (25 mL), suspend in dry THF (150 mL) and cool to 0° C. under N 2 . Add the product (25.35 g, 0.0762 mol) of Step. 2A in dry THF (150 mL) dropwise. Stir at 23° C. for 30 mins, reflux for 6 h, and stir at 23° C. for 16 h. Cool to 0° C. and add water (150 mL) and 1N HCl (150 mL). Concentrate and extract with EtOAc (3×200 mL). Wash combined organic extracts with saturated aqueous NaCl, dry (MgSO 4 ), filter and concentrate. Purify by chromatography (600 mL of flash silica gel; eluant: 5% CH 3 OH--CH 2 Cl 2 ). Combine appropriate fractions and concentrate to give 21.62 g (0.0729 mol, 96%) of the title compound as a yellow oil. MS (FAB): m/e 297 (M+1) ##STR69##
Treat the product of Step 2B in a procedure similar to that described for Prep. 6A. MS (FAB): m/e 283 (M+1). ##STR70##
Combine the product (1.50 g, 5.06 mmol) of Prep. 6A and Lawesson reagent (1.13 g, 2.78 mmol) in dry THF (20 mL) under N 2 . Stir at 23° C. for 20 h. Concentrate and purify by chromatography (200 mL of flash silica gel; eluant: 1:3 EtOAc:hexane, 1:2 EtOAc:hexane, then 1:1 EtOAc:hexane). Combine appropriate fractions and concentrate to give 1.30 g (4.16 mmol, 82%) as a green oil. MS (FAB): m/e 313 (M+1). ##STR71##
Dissolve the product (2.50 g, 8.43 mmol) of Prep. 6A in dry THF (30 mL), add borane-DMS (16.9 mL of 2.0M in THF, 33.74 mmol) and reflux for 20 h. Cool to 0° C. and add CH 3 OH (20 mL). Concentrate, add EtOH (50 mL) and K 2 CO 3 (4.66 g, 33.74 mmol). Reflux for 4 h and cool to 23° C. Add water (100 mL), concentrate and extract with CH 2 Cl 2 (4×50 mL). Dry combined organic extracts (MgSO 4 ), filter and concentrate. Purify by chromatography (200 mL of flash silica gel; eluant: 7% CH 3 OH--CH 2 Cl 2 ). Combine appropriate fractions and concentrate to give 1.72 g (6.09 mmol, 72%) of the title compound as a colorless oil. MS (FAB): m/e 283 (M+1). ##STR72##
Dissolve the product (1.50 g, 5.06 mmol) of Prep. 6A in dry THF (20 mL) and cool to -78° C. under N 2 . Add (CH 3 ) 3 Si! 2 NLi (5.5 mL of 1.0M in THF, 5.5 mmol) and stir at -78° C. for 1 h. Add bromomethylcyclopropane (0.820 g, 0.59 mL, 6.07 mmol), warm slowly to 23° C. and stir for 16 h. Add saturated aqueous NH 4 Cl (40 mL), extract with EtOAc (3×30 mL), wash combined organic extracts with saturated aqueous NaCl, dry (MgSO 4 ), filter and concentrate. Purify by chromatography (175 mL of flash silica gel; eluant: 2% CH 3 OH--CH 2 Cl 2 then 4% CH 3 OH--CH 2 Cl 2 ). Combine appropriate fractions and concentrate to give 0.93 g (2.65 mmol, 53%) of the title compound as a colorless oil. MS (FAB): m/e 351 (M+1) ##STR73##
Treat the product of Prep. 6A in a procedure similar to that described for Prep. 6G, using allyl bromide. MS (Cl/CH 4 ): m/e 337 (M+1). Step 3: Separately dissolve the products of Prep. 6A to 6H in CH 2 Cl 2 , add trifluoroacetic acid and stir at 23° C. for 4 h. Concentrate, add 1N NaOH, extract with CH 2 Cl 2 , dry the combined organic extracts (MgSO 4 ), filter and concentrate to obtain the corresponding substituted piperidines:
__________________________________________________________________________Prep. Substituted Piperidine Data__________________________________________________________________________6-1 ##STR74## MS (Cl/CH.sub.4): m/e 197 (M + 1)6-2 ##STR75## MS (Cl/CH.sub.4): m/e 183 (M + 1)6-3 ##STR76## MS (Cl/CH.sub.4): m/e 213 (M + 1)6-4 ##STR77## MS (Cl/isobutane: m/e 183 (M + 1)6-5 ##STR78## MS (Cl/CH.sub.4): m/e 251 (M + 1)6-6 ##STR79## MS (Cl/CH.sub.4): m/e 237 (M + 1)__________________________________________________________________________
Preparation 7
Substituted Piperidines--Method B ##STR80##
Combine 1-benzyl-4-piperidone (2.00 g, 10.6 mmol) and 3-pyrrolinol (0.92 g, 10.6 mmol) in titanium isopropoxide (3.75 g, 3.9 mL, 13.2 mmol) and dry CH 2 Cl 2 (4 mL). Stir at 23° C. under N 2 for 5 h. Add EtOH (30 mL) and NaCNBH3 (0.66 g, 10.6 mmol) and stir for 16 h. Add water (50 mL) and CH 2 Cl 2 (50 mL), filter through celite, separate filtrate layers and extract with CH 2 Cl 2 (2×50 mL). Wash combined organic extracts with saturated aqueous NaHCO 3 , dry (MgSO 4 ), filter and concentrate. Purify by chromatography (150 mL of flash silica gel; eluant: 10% CH 3 OH with NH 3 --CH 2 Cl 2 , 15% CH 3 OH with NH 3 --CH 2 Cl 2 , then 20% CH 3 OH with NH 3 --CH 2 Cl 2 .) Combine appropriate fractions and concentrate to give 1.88 g (7.22 mmol, 68%) as a colorless oil.
MS (Cl/CH 4 ): m/e 261 (M+1).
Using the procedure of Prep. 7A and the appropriate amine, prepare Preps. 7B and 7C: ##STR81##
Step 2: Separately treat each of Preps. 7A, 7B and 7C with Pd/C catalyst in CH 3 OH and formic acid at 23° C. under N 2 for 16 h. Filter each mixture through celite, washing with CH 3 OH, concentrate the filtrates, add 1.0N NaOH and extract with 1:4 EtOH:CH 2 Cl 2 , dry, filter and concentrate to obtain Preps. 7-1, 7-2 and 7-3:
______________________________________Prep. Substituted Piperidine Data______________________________________7-1 ##STR82## MS (Cl/CH.sub.4): m/e 171 (M + 1) m.p. 138-140° C.7-2 ##STR83## MS (Cl/CH.sub.4): m/e 212 (M + 1)7-3 ##STR84## MS (Cl/CH.sub.4): m/e 181 (M______________________________________ + 1)
Preparation 8
Substituted Piperidines--Method C
Step 1: Using 1,1 -dimethyethyl 4-formyl-piperidinecarboxylate and the appropriate amine in a reductive amination procedure similar to that described in Example 42, Step 9, Preparations 8A, 8B and 8C are prepared: ##STR85##
Step 2: Using the procedure described in Preparation 6, Step 3, prepare the following compounds:
______________________________________Prep.Substituted Piperidine Data______________________________________8-1 ##STR86## MS (FAB): m/e 213 (M + 1)8-2 ##STR87## MS (Cl/CH.sub.4): m/e 213 (M + 1)8-3 ##STR88## MS (Cl/CH.sub.4): m/e 199 (M______________________________________ + 1)
Preparation 9
Substituted Heptan- and Hexanaldehydes ##STR89##
Treat a suspension of 4 3,5-bis(trifluoromethyl)phenyl!butyric acid (5.15 g, 17.55 mmol) in dry Et 2 O (50 ml) with SOCl 2 (2.6 ml, 2 equiv.) and add 3 drops of pyridine. Stir for 15 h at ambient temperature, then decant the solution from pyridine hydrochloride and evaporate in vacuo to obtain the acid chloride (5.4 g, 99%) as an oil.
Cool a 1M solution of (CH 3 ) 3 Si! 2 NLi (50 ml, 8.3 g, 49.63 mmol) in THF to -30° C. and add a solution of 3,4-dichlorophenylacetic acid (4.09 g, 19.8 mmol) in dry THF (20 ml) dropwise, maintaining the temperature at or below -14° C. Stir at 0°-5° C. for 1 h. Cool the reaction mixture to -78° C. and add a solution of 4- 3,5-bis(trifluoromethyl)phenyl!butyryl chloride (5.41 g, 15 16.97 mmol) in dry THF (10 ml) dropwise over 15 min. Stir at 0° C. for 1 h, then allow to warm up to room temperature and stir for 1 h. Pour on 50 ml of 1N HCl and ice, stir 30 min and extract the aqueous layer with EtOAc. Wash with saturated aqueous NaHCO 3 (200 ml), dry (MgSO 4 ), filter and concentrate in vacuo to obtain 7.5 g of crude product. Purify by flash chromatography over 180 g silica gel (particle size 32-63) and elute with hexane: CH 2 Cl 2 (70:30) to obtain 3.86 9 (8.71 mmol, 51%) of the title crystalline compound. 1 H NMR (CDCl 3 , 300 MHz)δ:7.72(s, 1 H Ar),7.60(s, 2H Ar), 7.41 (d, J=8.3, 1 H Ar), 7.29(s, 1H Ar), 7.02(m, 1H Ar), 3.66(s, 2H, CH 2 ),2.72(t, 2H, CH 2 , J=7), 2.54(t, 2H, CH 2 , J=7), 1.94(m, 2H, CH 2 ). IR (CH 2 Cl 2 ): 1720 cm -1 (C=O).
Using a similar procedure with the appropriate acid, prepare the following compounds: ##STR90## Yield 66%. 1 H NMR (CDCl 3 , 200 MHz)δ: 7.72(s, 1H Ar), 7.60(s, 2H Ar), 7.38(d, 1H Ar, J=8), 7.26(1H Ar), 6.98(m, 1H Ar), 3.65(s,2H, CH 2 ), 3.02(t, 2H, CH 2 , J=6.4), 2.86(t, 2H, CH 2 (t, 2H, CH 2 , J=6.4)).
IR (CH 2 Cl 2 ):1720 cm -1 (C=O). ##STR91##
Yield 60%. FAB-Ms: m/z 383 ( Cl 9 H 20 35 Cl 2 O 4 +H!+, 47%). ##STR92##
Step 2
Add a solution of the product of Step 1 (3.80 g. 8.57 mmol) in dry THF (20ml) to a stirred solution of (CH 3 ) 3 Si! 2 NLi (9.35 ml, 9.3 mmol) in THF at -78° C. Add a solution of 2-chloro-N-methoxy-N-methyl-acetamide (1.18 g, 8.58 mmol) in THF (10 ml) dropwise over 10 min, add 1.2 g of Kl, allow the reaction mixture to warm to room temperature over a period of 1 h and stir overnight. Add 10 ml of saturated aqueous NH 4 Cl and evaporate the solvent in vacuo. Partition the residue between CH 2 Cl 2 (150 ml) and H 2 O (150 ml). Wash the organic layer with aqueous NaHCO 3 (150 ml), dry (MgSO 4 ), filter and evaporate in vacuo to obtain 3.6 g (77%) of the oily product.
FAB-Ms: m/z 544 ( C 23 H 21 35 Cl 2 F 6 NO 3 +H! + , 61%).
Using the procedure of Step 2, treat compounds 9-1A and 9-B of Step 1 to obtain: ##STR93##
Treat a solution of the product of Step 2 (3.5 g, 6.43 mmol) in dry pyridine (10 ml) with 0-methoxylamine HCl (0.65 g, 7.78 mmol) and heat to 60° C. for 1 h. Remove the pyridine in vacuo, partition the residue between CH 2 Cl 2 and water. Dry over MgSO 4 , filter and evaporate in vacuo to obtain the mixture of E- and Z-oximes. Separate E-oxime and Z-oxime by flash chromatography using 120 g of SiO 2 (particle size 32-63) and eluant: EtOAc:hexane (20:80) to obtain 2.91 g (79%) of E-isomer and 0.47 g (12.8%) of Z-isomer.
9-3(E): FAB-Ms (E-isomer): m/z 573 ( C 24 H 24 35 Cl 2 F 6 N 2 O 3 +H! + , 27%).
1 H NMR- E-isomer (CDCl 3 , 300 MHz)δ4.08 (H-γ).
9-3(Z): FAB-Ms (Z-isomer): m/z 573 ( C 24 H 24 35 Cl 2 F 6 N 2 O 3 +H! + , 70%).
1 H NMR- Z-isomer (CDCl 3 , 300 MHz)δ4.69 (H-γ).
Using the procedure of Step 3, treat compounds 9-3A and 9-3B to obtain the following: ##STR94## Yield: 73% of E-isomer (m.p. 62°-64° C.) and 18% of Z-isomer.
9-3A(E): Ms-Cl+CH 4 (E-isomer): m/z 559 ( C 23 H 22 35 Cl 2 F 6 N 2 O 3 +H! + , 100%). 1 H NMR- E-isomer (CDCl 3 , 300 MHz)δ4.11 (H-γ).
9-3A(Z): Ms-Cl+/CH 4 (Z-isomer): m/z 559 ( C 23 H 22 35 Cl 2 F 6 N 2 O 3 +H! + , 100%). 1 H NMR-Z-isomer (CDCl 3 , 300 MHz)δ4.71 (H-γ). ##STR95## Yield: 61% of E-isomer (m.p. 114°-118° C.) and 23% of oily Z-isomer.
9-3B(E): FAB-Ms (E-isomer): m/z 513 ( C 24 H 30 35 Cl 2 N 2 O 6 +H! + , 42%).
1 H NMR- E-isomer (CDCl 3 , 300 MHz) 8 4.10 (H-γ).
9-3B(Z): FAB- Ms (Z-isomer): m/z 513 ( C 24 H 30 35 CL 2 N 2 O 6 +H! + , 60%). ##STR96##
To a solution of the E-isomer of Step 3 (9-3(E)) (1.43 g, 2.54 mmol) in THF (20 ml) at -78° C., add 6 ml of 1M Dibal-H in hexane (6 mmol) over a period of 5 min. Stir at -78° C. for 30 min, then add 15 ml of H 2 O and 1 g of NaF. Allow the reaction mixture to warm to room temperature, dilute with EtOAc (100 ml), separate organic layer from aqueous, dry (MgSO 4 ), filter and evaporate in vacuo. Treat the residue with Et 2 O, filter and evaporate in vacuo. Use the product immediately, without purification. Using the procedure described in step 4, treat preparative compounds 9-3A(Z), 9-3B(E) and 9-3B(Z) to obtain the corresponding aldehydes 9-A(Z), 9-B(E) and 9-B(Z). ##STR97##
Preparation 10
Treat a solution of 2-thiopheneaceticacid (1.6 g, 11.2 mmole) in anhydrous THF (100 mL, -78° C.) with lithiumhexadimethylsilazide (24.5 mmole, 1M THF soln.). Warm the solution to 0° C. over a period of 2 h, then cool to -78° C. and add ethyl 3,5-bis(trifluoromethyl)phenyl!-methoxy!-acetate (3.55 g, 11.2 mmole) dropwise as a THF solution (10 mL). Stir the resulting mixture for 4 h and allow the temperature to warm to 0° C. Quench the reaction with 1 ml HOAc and stir for 4h. Dilute the reaction with EtOAc (100 mL), wash the organics with water (2×50 mL) and brine (1×50 mL), dry (Na 2 SO 4 ) and concentrate to obtain 3.4 g of crude product. Purify by silica gel chromatography (3:7 Et 2 O:hexane ) to give the title compound, 2.8 g (7.3 mmole, 65.4%) as a colorless foam.
MS: (Cl+/CH 4 ) (M+H + ) 383.
Preparation 11 ##STR98##
Treat a solution of 4-picoline (1.42g, 15 mmole) in anhydrous THF (50 mL, -10° C.) with phenyllithium (15 mmole, 8.3 mL cyclohexane:Et 2 O) and stir for 1 h at 0° C. Cool the solution to -78° C. and add the product of Example 47, Step 1 (5.27 g, 15 mmole) dropwise as a THF solution (10 mL). Stir the resulting mixture for 4 h (-78° C. to 0° C.) and quench with saturated aqueous NH 4 Cl (10 mL). Extract with EtOAc (100 mL), wash with water (2×50mL), brine (50 mL), dry (Na 2 SO 4 ), and concentrate. Purify the crude by silica gel column chromatography (8:2 EtOAc:hexane) to obtain the title compound. (2.5 g, 44%). MS: (Cl+/CH 4 ) (M+H + ) 378.
Preparation 12 ##STR99##
Step 1: Treat a solution of 3,5-bis(triflouromethyl)benzaldehyde (10 g, 0.04 moles) in toluene (130 mL) with carboethoxymethylenetriphenyl-phosphorane (14.38 g, 0.041 moles) and reflux in toluene for six hours. Remove the solvent under vacuum and dissolve the residue in CH 2 Cl 2 and filter through a pad of silica gel (50 g) on a suction filter. Concentrate the filtrate and dry under vacuum to give the title compound (13.01 g) as a white solid. MS(Cl, M+H + ), m/e 313.
Step 2: Treat a degassed solution of the product of Step 1 (31.0 g, 0.04 mmoles) in EtOH (60 mL) with 10% Pd/C (1.3 g), introduce H 2 gas to a pressure of 20 psi. and shake at room temperature for 2 hours. Filter through celite and remove solvent by vacuum distillation to obtain the title compound (13.0 gm). MS(Cl, M+H 30 ), m/e 315.
Step 3: Treat an EtOH solution (200 mL) of the product of Step 2 (13 g, 0.041 moles) with an aqueous solution of NaOH (50%, 12 ml, 0.26 moles). Heat the solution at reflux for 3 h. Cool the mixture to room temperature and remove the solvent by vacuum distillation. Dissolve the residue in water (150 mL) and acidify to pH 2 with concentrated HCl. Extract the product into EtOAc (2×100 mL), wash the EtOAc layer with water (2×50 mL), dry (MgSO 4 ) and remove the solvent by vacuum distillation to afford a white solid (11.26 g). M. p. 65°-67° C. MS (Cl, M+H + ) m/e 287.
Step 4: Treat a solution of the product of Step 3 (11.26 g, 0.039 moles) in CH 2 Cl 2 (300 mL) with oxalyl chloride (5.99 g, 0.047 moles, added dropwise with stirring) and a trace of DMF. Stir the mixture at room temperature for 2 h and heat to reflux for 15 min. Cool the reaction to room temperature and concentrate to dryness under vacuum. Repeatedly dissolve the residue in toluene (2×100 mL) and concentrate to dryness to afford an off-white solid. Dissolve the solid in CH 2 Cl 2 (100 mL) and add dropwise into a cold (0° C.) solution of phenol (3.7 g, 0.04 moles) in a mixture of CH 2 Cl 2 (100 mL) and pyridine (15 mL). Stir at room temperature overnight and concentrate to a yellow oil. Redissolve in CH 2 Cl 2 (100 mL), wash with aq. 1M HCl (2×50 mL), water (1×50 mL) and dry (MgSO 4 ). Remove the solvent by vacuum distilation to afford a light yellow solid (9.2 g). M.p. 39°-40° C. MS (Cl, M+H + ) m/e 363.
Preparation 13 ##STR100##
Treat a suspension of 3.5-bis(trifluoromethyl)phenyl acetic acid (5 g, 18 mmoles) in CH 2 Cl 2 (100 mL) with oxallyl chloride (4.7 g, 3.3 mL, 37 mmoles) and a trace (3 drops) of DMF. Stir the mixture at room temp. under N 2 for 1 h and then heat to reflux for 1 h. Cool the mixture and remove the solvent in vacuo. Dilute the residue (5.2 g) with toluene (20 mL) and concentrate under reduced pressure (3 times). Dilute a portion (2.9 g, 10 mmoles) of the crude residue with CH 2 Cl 2 (10 mL) and add to a rapidly stirred biphasic mixture of water (30 mL), concentrated NH 4 OH and CH 2 Cl 2 (30 mL). Stir the mixture an additional 15 min to obtain a precipitate. Separate the organic phase, dilute with 10 mL of EtOAc to dissolve the precipitate and dry (MgSO 4 ). Remove the solvent by vacuum distilation and triturate the residue with Et 2 O/hexane (30 mL, 4:1). Collect the solid (2.48 g) by vacuum filtration and dry under vacuum. Dissolve a portion of the solid (1.47 g, 5.4 mmoles) in THF (20 mL) and add solid LiAlH 4 (0.51 g, 50 mmole) in small portions. Heat the mixture to reflux for 3 h, cool and then treat with 20 mL of a mixture of CH 3 OH and 2N NaOH (9:1). After rapidly stirring for 20 minutes, remove the precipatate by filtration through celite. Dilute the organic phase with EtOAc (25 mL) and extract with 1N HCl (30mL). Basify the aqueous phase with 3N NaOH and extract with CH 2 Cl 2 (2×30 mL). Dry the organic phase (MgSO 4 ) and concentrate under vacuum to give 0.22 g of the title compound. Concentrate the EtOAc layer from above under vacuum to a reddish oil and triturate with Et 2 O to obtain an additional 0.11 gms of the title compound as the HCl salt. MS(Cl, M+H + ), m/e 258.
EXAMPLE 1
1-(3.5-bis(trifluoromethyl)phenyl methoxy!-3-(3.4-dichlorophenyl)-5-(4-hydroxy-4-phenyl-1-piperidinyl)-2-pentanone O-methyloxime ##STR101##
Treat a solution of the product of Preparation 4 (270 mg, 0.417 mmol) in dry pyridine (5 mL) with O-methoxylamine HCl (52 mg, 0.626 mmol, 1.5 eq) and heat to 60° C. for 30 min. Allow the vessel to cool to 23° C. and remove the pyridine in vacuo. Take up the crude product in a minimal amount of CH 2 Cl 2 (2 mL) and apply to a silica gel column (2.5 cm×15 cm) packed with hexane:EtOAc:triethylamine (66:33:1). Elute with the same solvent system to obtain 190 mg (0.281 mmol, 67%) of the title compound as a colorless foam.
HRMS (FAB, M+H + ): m/e calc'd for C 32 H 33 N 2 O 3 Cl 2 F 6 ! + : 677.1772, found 677.1785.
Examples 1 A to 1 F are prepared from the product of Preparation 4 in a procedure similar to that described for Example 1:
__________________________________________________________________________ ##STR102## HRMS Starting (FAB, M + H.sup.+) HRMSEx. A Material calc'd Found__________________________________________________________________________1A NOH hydroxyl 663.1616 663.1625 (Z isomer) amine.HCl1B HON hydroxyl 663.1616 663.1631 (E isomer) amine.HCl1C NOCH.sub.2 Ph O-benzyl- 753.2085 753.2069 hydroxyl amine.HCl1D NOCH.sub.2 CH.sub.3 O-ethyl- 691.1929 691.1922 hydroxyl amine.HCl1E NOCH.sub.2 CHCH.sub.2 O-allyl- 703.1929 703.1946 hydroxyl amine.HCl1F NOC(CH.sub.3).sub.3 O-t-butyl- 719.2242 719.2252 hydroxyl amine.HCl1G NOCH.sub.2 COOH H.sub.2 NOCH.sub.2 CO.sub.2 H.HCl 721 (M + 1)1H NO(CH.sub.2).sub.2 COOH H.sub.2 NO(CH.sub.2).sub.2CO.sub.2 H.HCl 735.1827 735.1807__________________________________________________________________________
EXAMPLE 2 ##STR103## Treat a solution of triethyl phosphonoacetate (18 μL, 0.11 mmol, 1.1 eq) in dry THF (1.5 mL) at 0° C. with (CH 3 ) 3 Si! 2 NNa (110 gL of .1M THF, 0.11 mmol, 1.1 eq). Stir for 30 min at 0° C. and add a solution of the ketone from Preparation 4 in dry THF (1.5 mL), using THF (0.5 mL) for quantitative transfer. Allow the reaction to warm to 23° C. and stir for 24 h. Quench the mixture with water and extract with CH 2 Cl 2 (3×25 mL). Wash the combined organic layers with 5% aqueous NaOH, dry (Na 2 SO 4 ) and concentrate to give the crude product as on oil. Purify by preparative TLC (0.5 mm silica gel; eluant: CH 2 Cl 2 /CH 3 OH (saturated with ammonia) (95:5) to obtain 41 mg (.057 mmol, 57%) of the title compound as a film.
HRMS (FAB, M+H + ): m/e calc'd for C 35 H 36 NO 4 F 6 Cl 2 ! + : 718.1926, found 718.1915.
EXAMPLES 3-4
Resolve the racemic compound of Example 1 A by HPLC using a Daicel Chiralcel AD chiral chromatography column (2.0 cm.×50.0 cm., 13% isopropanol in hexane). Four injections of 100 mg each provide:
Example 3, the (+) isomer:
150 mg; t.sub.R =10 min.;.sup. α!.sbsp.25 D=+6.5°,(c=0.01, CHCl.sub.3)
Example 3A, the (-) isomer:
140 mg;t.sub.R =17 min.; .sup. α!.sbsp.25 D=-9.5°, (c=0.01, CHCl.sub.3).
In a similar manner, resolve the compound of Example 1 B to obtain Examples 4 and 4A:
Enantiomer A: t.sub.R =21 min.; HRMS (FAB, M+H.sup.+): m/e calc'd for C.sub.31 H.sub.31 N.sub.2 O.sub.3 F.sub.6 Cl.sub.2 !.sup.+ : 663.1616, found 663.1601;
Enantiomer B: t.sub.R =31 min.; HRMS (FAB, M+H.sup.+): m/e calc'd for C.sub.31 H.sub.31 N.sub.2 O.sub.3 F.sub.6 Cl.sub.2 !.sup.+ : 663.1616, found 663.1621.
Prepare examples 5-6 from the products of Example 3 and 3A, respectively, in a manner similar to that described in Example 8, using CH 3 l as the alkyl halide and DMF as the solvent.
EXAMPLE 5 ##STR104## HRMS (FAB, M+H + ): m/e calc'd for C 32 H 33 N 2 O 3 F 6 Cl 2 ! + : 677.1772, found 677.1769.
EXAMPLE 6 ##STR105## HRMS (FAB, M+H + ): m/e calc'd for C 32 H 33 N 2 O 3 F 6 Cl 2 ! + : 677.1772, found 677.1762.
EXAMPLE 7 ##STR106##
Treat a solution of the ketone of Preparation 4 (100 mg, 0.154 mmol) in ethanol (3 mL) with acetic acid (3 drops) followed by 1 -amino-4-methyl-piperizine. Stir the mixture at 60° C. for 1 h, concentrate and triturate with water using sonication. Filter the resulting colorless solid and wash with water (3 mL) to give 86 mg (0.115 mmol, 75%) of the product as a colorless solid, mp 48°-49° C.
HRMS (FAB, M+H + ): m/e calc'd for C 36 H 40 N 4 O 2 Cl 2 F 6 ! + : 745.2511, found 745.2502.
Using a similar procedure but substituting 4-aminomorpholine, dimethylhydrazine and 4-amino-i-piperazineethanolfor 1-amino-4-methyl-piperizine, obtain compounds 7A, 7B and 7C, respectively, as E/Z mixtures:
______________________________________ ##STR107## HRMS calc'd (FAB, HRMSEx. N(R.sup.2)(R.sup.3) M + H.sup.+) Found______________________________________7A ##STR108## 732.2194 732.21847B N(CH.sub.3).sub.2 690.2089 690.21007C ##STR109## 775.2616 775.2641______________________________________ ##STR110##
Treat a solution of Example 1A (400 mg, 0.603 mmol) in dry DMF (12 mL) at 0° C. with 60% NaH in mineral oil (48 mg), stir for 40 min and treat with methyl bromoacetate (60 μL, 0.633 mmol, 1.05 eq). Stir for 30 min, pour into EtOAc (250 mL) /half saturated NaHCO 3 (200 mL) and extract. Wash the organic layer with water (2×100 mL), then brine (10 mL) and dry over Na 2 SO 4 . Purify the crude mixture by silica gel chromatography (4×15 cm; hex/EtOAc 1:1 w/2% NEt 3 ) to give 361.8 mg (0.492 mmol, 82%) of the pure product as an oil.
HRMS (FAB, M+H + ): m/e calc'd for C 34 H 34 Cl 2 F 6 N 2 O 5 ! + : 735.1827, found 735.1839.
Using a similar procedure, treat the product of Example 1A with the appropriate alkyl halide to obtain the following compounds 8A-8L:
______________________________________ ##STR111## HRMS calc'd (FAB, HRMSEx. R.sup.1 Alkyl Halide M + H.sup.+) Found______________________________________8A CH.sub.2 CH.sub.2 CO.sub.2 CH.sub.3 Me 749.1956 749.1984 3-Br-propionate8B CH.sub.2 CN Br-acetonitrile 702.1725 702.17208C CH.sub.2 (CH.sub.2).sub.2 CO.sub.2 CH.sub.3 Me 4-Br-butyrate 763.2140 763.21438D CH.sub.2 (CH.sub.2).sub.3 CO.sub.2 CH.sub.3 Me 5-Br-valerate 777.2297 777.23048E CH.sub.2 CH.sub.2 OH 2-Br-1- 707.1878 707.1856 (t-Bu-diMe- silyloxy)-ethane*8F CH.sub.2 CH.sub.2 OCH.sub.3 2-Br-ethyl 721.2035 721.2029 Me ether8G CH.sub.2 CH.sub.2 CH.sub.2 -Phthalyl N-(3-Br-propyl)- 850.2249 850.2248 phthalimide8H CH.sub.2 CH(OH)CH.sub.2 OH (+/-)-3-Br,1,2- 737.1984 737.1982 bis-(t-Bu-diMe- silyl-oxy)- propane*8I CH.sub.2 OCH.sub.3 Br-methyl 707.1878 707.1855 Me ether8J CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.3 2-methoxy- 751.2140 751.2159 ethoxy-Me Cl8K##STR112## epibromohydrin 719.1878 719.18818L##STR113## 4-(3-Cl-propyl)-1- trityl-imidazole** 771.2303 771.2305______________________________________ *Followed by desilylation with 1M TBAF in THF (3 h, 23° C.). **Followed by deprotection of the trityl group by stirring in PPTS/MeOH for 3 h at 60° C.
EXAMPLE 9 ##STR114##
Treat a solution of the product of Example 8 (57 mg, 0.078 mmol) in MeOH (3mL) at 0 ° C. with gaseous ammonia for 5 min. After venting 2-3 times, seal the vessel with a polypropylene cap and stir until TLC shows the reaction is complete (20 h) to give (56 mg, 0.078 mmol, >99%) of the pure product as a colorless powder.
HRMS (FAB, M+H + ): m/e calc'd for C 33 H 33 Cl 2 F 6 N 3 O 4 ! + : 720.1831, found 720.1841.
Using a similar procedure, treat the product of Example 8 with the appropriate amine to obtain the following compounds 9A, 9B and 9E; treat the product of Example 8A to obtain 9C and 9D; and treat the products of Examples 8C and 8D to obtain 9F and 9G, respectively:
______________________________________ ##STR115## HRMS calc'd (FAB, HRMSEx. R.sup.1 Amine M + H.sup.+) Found______________________________________9A CH.sub.2 CONHCH.sub.3 CH.sub.3 NH.sub.2 734.1987 734.20089B CH.sub.2 CON(CH.sub.3).sub.2 (CH.sub.3).sub.2 NH 748.2144 748.21239C CH.sub.2 CH.sub.2 CONH.sub.2 ammonia 734.1987 734.19769D CH.sub.2 CH.sub.2 CONHCH.sub.3 CH.sub.3 NH.sub.2 748.2144 748.21249E CH.sub.2 CONHOH H.sub.2 NOH in MeOH 736.1780 736.17679F CH.sub.2 CH.sub.2 CH.sub.2 CONH.sub.2 ammonia 748.2144 748.21699G CH.sub.2 (CH.sub.2).sub.3 CONH.sub.2 ammonia 762.2300 762.2303______________________________________
EXAMPLES 10 to 18
Using the procedures described below, compounds of the following structural formula were prepared, wherein the definitions of R 1 are shown in the table below:
______________________________________ ##STR116## HRMS calc'd HRMSEx. R.sup.1 (FAB, M + H.sup.+) Found______________________________________10 OCONHCH.sub.3 720.1831 720.182011##STR117## 735.1940 735.195612##STR118## 749.2096 749.210913##STR119## 763.1776 763.179914##STR120## 888.3093 888.309015##STR121## 804.1613 804.159816##STR122## 842.1947 842.196517##STR123## 794.2198 794.219518##STR124## 778.2249 778.2251______________________________________
EXAMPLE 10
Treat a solution of the product of Example 1 (100 mg, 0.151 mmol) in CH 2 Cl 2 (1 mL) with CH 3 NCO (9 μL, 0.151 mmol, 1 eq) and pyridine (18 μL, 0.227 mmol, 1.5 eq) and stir for 60 hr. Concentrate in vacuo and purify by silica gel chromatography (2.5×18 cm; EtOAc/Hex 2:1 w/2% NEt 3 ) to give 88 mg (0.122, mmol 81%) of the pure product as a film.
EXAMPLE 11
Treat a suspension of H 2 NOH.HCl (47 mg, 0.68 mmol, 5 eq) in ethanol with KOH in MeOH (680 μL, 0.68 mmol, 5 eq), sonicate for 5 min and then add to a solution of Example 8B (95 mg, 0.135 mmol) in ethanol (5 mL). Heat for 2.5 h at 60° C., filter, concentrate in vacuo and purify by silica gel chromatography (2.5×14 cm; CH 2 Cl 2 /MeOH (NH 3 ) 95:5) to give 98.3 mg (0.134 mmol, 99%) of the product as a film.
EXAMPLE 12
Use a procedure similar to that described in Example 11 using the product of Example 8B as the starting material, H 2 NOCH 3 .HCl as the alkoxyl amine and 2,2,2-trifluoroethanol as the solvent.
EXAMPLE 13
Treat a solution of Example 8H (50 mg, 0.068 mmol) in 1,2 dichloroethane (1 mL) with carbonyidiimidazole (60 mg, 0.38 mmol, 5 eq), stir for 10 hr at reflux, and concentrate in vacuo. Purify by silica gel chromatography (1.5×121 cm; CH 2 Cl 2 /MeOH (NH 3 ) 98:2) to give 40 mg (0.052mmol, 77%) as a film.
EXAMPLE 14
Treat a solution of Example 1G (100 mg, 0.139 mmol) in THF (2 mL) and N-isopropyl-1-piperazine-acetamide (77 mg, 0.417 mmol, 3 eq) with Et 3 N (29 μL, 0.209 mmol, 1.5 eq) and DEC (40 mg, 0.209 mmol, 1.5 eq), stir until complete by TLC (72 hr), and partition between EtOAc (50 mL) /10% citric acid (20 mL). Wash with water (25 mL), sat'd NaHCO 3 (25 mL), brine (10 mL), and dry over Na 2 SO 4 . Purify by silica gel chromatography (2.5×10 cm; CH 2 Cl 2 /MeOH (NH 3 ) 9:1) to give 36.2 mg (0.041 mmol, 29%) of the desired product as a foam.
EXAMPLE 15
In a similar fashion to Example 14, use 2-amino-1,3,4-thiadiazole as the amine to obtain the desired product.
EXAMPLE 16
In a similar fashion to Example 14, use 3-aminopyrazine-2-carboxylic acid as the amine to obtain the desired product.
EXAMPLE 17
In a similar fashion to Example 14, use (+/-)-3-amino-1,2-propanediol as the amine to obtain the desired product.
EXAMPLE 18
In a similar fashion to Example 14, use 2-methoxyethyl amine as the amine to obtain the desired product.
Examples 19, 19A and 19B ##STR125##
Using the procedures described below, compounds of the structural formula above were prepared, wherein the definitions of R 1 are shown in the following table:
______________________________________ HRMS calc'd HRMSEx. R.sup.1 (FAB M + H.sup.+) Found______________________________________19 CH.sub.2 CN 634.1198 634.120619A CH.sub.2 CH.sub.2 OH 639.1351 639.134219B ##STR126## 667.1351 639.1342______________________________________
EXAMPLE 19
Step 1: Prepare the allyl oxime ether of the product of Example 22, Step 2, using a procedure similar to that used in Example 1, employing 0 allylhydroxylamine HCl as the alkoxyl amine.
Step 2: Deprotect the silyl protective group in a procedure similar to that describe in Example 22, Step 4.
Step 3: Alkylate the hydroxyl group with 3,5-dichlorobenzylbromide in a procedure similar to that in Example 22.
Step 4: Treat a solution of the product of step 3 (285 mg, 0.426 mmol) in 80% aqueous EtOH with Pd(PPh 3 ) 4 (25 mg, 0.021 mmol, 0.05 eq) and triethylammoniumformate (2.13 mL of IM solution in THF, 5 eq) and stir at reflux for 4 h. Cool, concentrate and purify by silica gel chromatography (2.5×16.5 cm; hex/EtOAc 1:1 w/2% NEt 3 ) to give 185 mg (0.3095 mmol, 73%) as a film.
Step 5: Treat the product of step 4 in a similar fashion to Example 8, using BrCH 2 CN as the alkyl halide.
EXAMPLE 19A
Treat the product of Example 19, step 4, in a similar fashion to Example 8, using 2-bromo-1-(tbutyldimethylsiloxy)ethane as the alkyl halide, followed by desilylation (3 h, 23° C.) with 1M TBAF in THF.
EXAMPLE 19B
Treat the product of Example 19 in a similar fashion to Example 11 to obtain the desired product.
EXAMPLES 20, 20A, 20B, 20C and 20D ##STR127##
Using the procedures described below, compounds of the structural formula above were prepared, wherein the definitions of R 1 are shown in the following table:
______________________________________ HRMS calc'dEx. R.sup.1 (FAB, M + H.sup.+) HRMS Found______________________________________20 H 586.1562 586.158220A CH.sub.2 CN 627 (M + 1)20B ##STR128## 658.1885 658.187320C CH.sub.2 CH.sub.2 OH 630.1824 630.181620D CH.sub.3 600.1718 600.1722______________________________________
EXAMPLE 20
Using a procedure similar to Example 47, substitute 3,5 dichlorobenzyl alcohol for 3,6 bistrifluorobenzyl alcohol in step 1; proceed in a similar manner through steps 2, 3, and 4, using allylhydroxylamine HCl as the alkoxyl amine in step 4. Proceed in a similar fashion through steps 5 and 6, using piperidinopiperidine in place of 4-phenyl-4-piperidinyl acetamide. Treat the resultant product using a procedure similar to Example 19, step 4, to obtain the desired compound.
Example 20A: Treat the product of Example 20 in a similar fashion to Example 8, using BrCH 2 CN as the alkyl halide to obtain the desired product.
EXAMPLE 20D
Treat the product of Example 20A in a similar fashion to Example 11 to obtain the desired product.
EXAMPLE 20C
Treat the product of Example 20 in a similar fashion to Example 8 using 2-bromo-1 -(t butyidimethylsiloxy)ethane as the alkyl halide, followed by desilylation (3 h, 23° C.) with 1M TBAF in THF to obtain the desired product.
EXAMPLE 20D
Treat the product of Example 20 in a similar fashion to Example 8 using CH 3 I as the alkyl halide to obtain the desired product.
EXAMPLES 21, 21A, 21B and 21C ##STR129##
Using the procedures described below, compounds of the structural formula above were prepared, wherein the definitions of R 1 are shown in the following table:
______________________________________ HRMS calc'dEx. R.sup.1 (FAB, M + H.sup.+) HRMS Found______________________________________21 CH.sub.3 631.1620 631.159921A CH.sub.2 CH.sub.2 OH 659.1725 659.170821B CH.sub.2 CN 654.1572 654.156321C ##STR130## 687.1787 687.1797______________________________________
EXAMPLE 21
Step 1: Prepare the oxime precusor using a procedure similar Example 20, using 1-(pyrrolidinocarbonylmethyl)piperizine in place of piperidinopiperidine.
Step 2: Treat the product of step 1, in a similar fashion to Example 8, using CH 3 I as the alkyl halide to obtain the desired product.
EXAMPLE 21A
Treat the product of Example 21, step 1, in a similar fashion to Example 8, using 2-bromo-1 -(tbutyidimethylsiloxy)ethane as the alkyl halide, followed by desilylation (3 h, 23° C.) with 1M TBAF in THF to obtain the desired product.
EXAMPLE 21B
Treat the product of Example 21, step 1, in a similar fashion to Example 8, using BrCH 2 CN as the alkyl halide to obtain the desired product.
EXAMPLE 21C
Treat Example 21B in a similar fashion to Example 11 to obtain the desired product.
EXAMPLE 22 ##STR131##
Step 1: β-(3,4-dichlorophenyl)-α- dimethyl(1,1-dimethylethyl)silyl!oxy!-methyl!-4-hydroxy-4-phenyl-1-piperidinebutanol
Treat a solution of the diol from Preparation 3 (1 9.8g, 46.6 mmol), Et 3 N (13 mL, 93.2 mmol) and dimethylaminopyridine (564 mg, 4.66 mmol) in CH 2 Cl 2 (300 mL)with TBSCI (8.44 g, 55.9 mmol) at 0° C. Allow the resulting solution to warm to room temperature and stir for 12-18 hours. Quench the reaction with water and extract with CH 2 Cl 2 (3×200 mL), combine the organic layers, dry over MgSO 4 , filter and concentrate under reduced pressure to give the crude product. Purify by silica gel chromatography (column: 10 cm×24 cm; pack column in CH 2 Cl 2 and elute using a gradient of 100% CH 2 Cl 2 to 10% CH 3 OH/CH 2 Cl 2 ) to obtain 21.5 g (39.8 mmol, 85%) of the title compound as a tan foam.
Step 2: 3-(3,4-dichlorophenyl)-1 - dimethyl(1,1 -dimethylethyl)silyl!oxy!-5-(4-hydroxy-4-phenyl-1 -piperidinyl)-2-pentanone
Treat a solution of the alcohol from Step 1 (21.5 g, 39.8 mmol) in CH 2 Cl 2 (600 mL) with PDC (22.5 g, 59.9 mmol). Stir the resulting black mixture for 12 h. Filter the reaction mixture through a plug of celite and wash plug with CH 2 Cl 2 (200 mL) and EtOAc (200 mL). Concentrate the filtrate under reduced pressure to give the crude product as a black oil. Purify by silica gel chromatography (column: 10 cm ×24 cm; pack column in CH 2 Cl 2 and elute using a gradient of 100% CH 2 Cl 2 to 5% CH 3 OH(NH 3 )/CH 2 Cl 2 ) to obtain 16 g (29.9 mmol, 75%) of the title compound as a tan foam.
Step 3: 3-(3,4-dichlorophenyl)-1 - dimethyl(1,1 -dimethylethyl)silyl!oxy!-5-(4-hydroxy-4-phenyl-1-piperidinyl)-2-pentanone 0-methyloxime
Treat a solution of the ketone from Step 2 (6.6 g, 12.3 mmol) and NaOAc (6.05 g, 73.8 mmol) in EtOH (110 mL) and H 2 O (27 mL) with NH 2 OCH 3 .HCl. Stir the resulting solution for 12-18 hours at room temperature. Concentrate under reduced pressure and partition the resulting residue between CH 2 Cl 2 (100 mL) and H 2 O (100 mL). Extract the aqueous layer with CH 2 Cl 2 (3×100 mL), dry the combined organic layers over MgSO 4 , filter and concentrate under reduced pressure to yield the crude product as a pale oil. This product is carried on without purification to the next step. HRMS (FAB, M+H + ): m/e cal'd for C 29 H 43 N 2 O 3 SiCl 2 ! + : 565.2420, found 565.2410.
Step 4: 3-(3,4-dichlorophenyl)-1 -hydroxy-5-(4-hydroxy-4-phenyl-1-piperidinyl)-2-pentanone 0-methyloxime
Treat a solution of the crude oxime from Step 3 (≦12.3 mmol) in THF (400 mL) with TBAF (15.4 mL, 15.4 mmol, 1M in THF) at 0° C. Stir the solution for 2 hours. Quench the reaction with water and extract the aqueous phase with EtOAc (3×100 mL). Dry the combined organic layers over MgSO 4 , filter and concentrate under reduced pressure to give the crude product as a yellow oil. Purify by silica gel chromatography (column: 7.5 cm×20 cm; pack column in CH 2 Cl 2 and elute using a gradient of 100% CH 2 Cl 2 to 5% CH 3 OH(NH 3 )/CH 2 Cl 2 ) to obtain 16 g (29.9 mmol, 75% from Example CAA2) of the title compound as a white solid. HRMS (FAB, M+H + ): m/e cal'd for C 23 H 29 N 2 O 3 Cl 2 ! + : 451.1555, found 451.1553.
Step 5: 3-(3,4-dichlorophenyl)-1 - (2,4-difluorophenyl)methoxy!-5-(4-hydroxy-4-phenyl-1-piperidinyl)-2-pentanone 0-methyloxime
Treat a solution of the hydroxy-oxime (200 mg, 0.44 mmol) of Step 4 in DMF at 0° C. with NaH (12 mg, 0.48 mmol). Stir the resulting mixture for 30 mins at 0° C. Add 2,4-difluorobenzylbromide (60 μL, 0.465 mmol) in one portion and remove cooling bath. Stir the reaction for 12-18 hours at room temperature. Quench the reaction with H 2 O and extract with EtOAC (3×30 mL). Dry the combined organic layers over MgSO 4 , filter and concentrate under reduced pressure to give the crude compound as a yellow oil. Purify by silica gel chromatography (column: 2.5 cm×15 cm; pack column in 50% EtOAc/Hexane and elute using a gradient of 50-100% EtOAc/Hexane) to obtain 128 mg (0.22 mmol, 50% ) of the title compound as a pale oil. HRMS (FAB, M+H + ): m/e cal'd for C 30 H 33 N 2 O 3 Cl 2 F 2 ! + : 577.1836, found 577.1832.
Examples 22A to 22AL, shown in the following table, are prepared from the product of Example 22, Step 4 in a procedure similar to that described for Example 22, Step 5, using the appropriate halide:
__________________________________________________________________________ ##STR132## HRMS calc'd (FAB, HRMSEx. T Starting Material M + H.sup.+) Found__________________________________________________________________________22A##STR133## ##STR134## 566.1977 566.198222B##STR135## ##STR136## 566.1977 566.197622C##STR137## ##STR138## 609.1899 609.188622D##STR139## ##STR140## 616.1981 616.198422E##STR141## ##STR142## 609.1899 609.190622F##STR143## ##STR144## 610.1198 610.120322G##STR145## ##STR146## 569.2338 569.233522H##STR147## ##STR148## 694.1618 694.161522I##STR149## ##STR150## 660.2008 660.200522J##STR151## ##STR152## 583.1879 583.188622K##STR153## ##STR154## 609.1253 609.125322L##STR155## ##STR156## 639.2141 639.214722M##STR157## ##STR158## 577.1836 577.184022N##STR159## ##STR160## 677.1909 677.190722O##STR161## ##STR162## 631.2494 631.249922P##STR163## ##STR164## 639.2141 639.214122Q##STR165## ##STR166## 609.1245 609.124122R##STR167## ##STR168## 639.2141 639.213522S##STR169## ##STR170## 615.1600 615.161322T##STR171## ##STR172## 627.1804 627.181322U##STR173## ##STR174## 577.1836 577.184522V##STR175## ##STR176## 627.1804 627.181322W##STR177## ##STR178## 586.1876 586.187322X##STR179## ##STR180## 585.1923 585.191622AK##STR181## ##STR182## 573.2087 673.209622AL##STR183## ##STR184## 589.2348 589.2342__________________________________________________________________________ Analysis AnalysisEx. T Starting Material Calc'd Found__________________________________________________________________________22Y##STR185## ##STR186## C, 68.33; H, 7.08; N, 4.69 C.sub.34 H.sub.42 N.sub.2 - O.sub.3 Cl.sub.2 C, 67.99; H, 7.38; N, 4.7922Z##STR187## ##STR188## C, 63.68; H, 6.17; N, 7.68 C.sub.29 H.sub.33 N.sub.3 - O.sub.3 Cl.sub.2.0.2 5 H.sub.2 O! C, 63.54; H, 6.43; N, 7.6822AA##STR189## ##STR190## C, 57.86; H, 5.48; N, 4.35 C.sub.31 H.sub.33 N.sub.2 - O.sub.4 Cl.sub.2 F.sub.3. H.sub.2 O! C, 58.16; H, 5.43; N, 4.4522AB##STR191## ##STR192## C, 64.18; H, 6.85; N, 4.54 C.sub.33 H.sub.40 N.sub.2 - O.sub.4 Cl.sub.2.H.s ub.2 O! C, 64.03; H, 7.06; N, 4.7722AC##STR193## ##STR194## C, 62.12; H, 6.29; N, 4.42 C.sub.32 H.sub.38 N.sub.2 - O.sub.3 Cl.sub.2.0.7 5 CH.sub.2 Cl.sub.2 ! C, 62.37; H, 6.85; N, 4.5322AD##STR195## ##STR196## C, 60.28; H, 6.01; N, 8.79 C.sub.32 H.sub.35 N.sub.4 - O.sub.4 Cl.sub.2. 1.5H.sub.2 O! C, 60.3; H, 6.02; N, 8.6022AE##STR197## ##STR198## C, 60.47; H, 6.34; N, 4.41 C.sub.32 H.sub.36 N.sub.2 - O.sub.5 Cl.sub.2. 2H.sub.2 O! C, 59.79; H, 6.34; N, 4.6722AF##STR199## ##STR200## C, 51.89; H, 5.23; N, 4.03 C.sub.30 H.sub.33 N.sub.2 - O.sub.3 Cl.sub.2 I. 1.5H.sub.2 O! C, 51.73; H, 5.22; N, 3.9822AG##STR201## ##STR202## C, 53.54; H, 5.80; N, 4.03 C.sub.31 H.sub.35 N.sub.2 - O.sub.4 BrCl.sub.2. 2.5H.sub.2 O! C, 53.47; H, 5.49; N,__________________________________________________________________________ 4.14
EXAMPLE 22AH
Using 2-acetoxy-1-bromo-1-phenylethane as the halide, prepare 1 -(acetyloxy)-3-(3,4-dichlorophenyl)-5-(4-hydroxy-4-phenyl-1-piperidinyl)-2-pentanone 0-methyloxime. HRMS (FAB, M+H + ): m/e cal'd for C 25 H 31 N 2 O 4 Cl 2 ! + : 493.1661, found 493.1652.
EXAMPLE 22AI
Using a-methylbenzylbromide as the halide, prepare 3-(3,4-dichlorophenyl)-5-(4-hydroxy-4-phenyl-1 -piperidinyl)-1 -(1 -phenylethoxy)-2-pentanone 0-methyloxime. HRMS (FAB, M+H + ): m/e cal'd for C 21 H 27 N 2 O 3 Cl 2 ! + : 555.2181, found 555.2181.
EXAMPLE 22AJ
Using cinnamoylbromide as the halide, prepare 3-(3,4-dichlorophenyl)-1- 3-phenyl-2-propenyloxy!-5-(4-hydroxy-4-phenyl-1 -piperidinyl)-2-pentanone 0-methyloxime. Mass spectrum (FAB): 567.
EXAMPLE 23 ##STR203##
Treat the product of Example 22, Step 4 (0.203 g) in THF (5 mL) at 0° C. with 1-phenyl-5-mercaptotetrazole (0.16 9), stir for 30-40 min. and add this mixture to a solution of DEAD (142 μL) and Ph 3 P (0.236 g) in THF (2.5 mL) also at 0° C. Stir the combined mixture for 30 min. and evaporate the solvent under reduced pressure. Purify the residue by silica gel chromatography eluting with mixtures of NH 3 /MeOH/CH 2 Cl 2 to give the title compound (0.038 g). Analysis: Calc'd for C 30 H 32 N 6 O 6 Cl 2 S. H 2 O; C, 57.23, H, 5.44, N,13.25. Found: C, 57.70, H, 5.17, N, 12.91.
Using the product of Example 22, Step 4, as starting material in the procedure of Example 23, prepare Examples 23A and 23 B, using 4,6-dimethylpyrimidine-2-thiol and phthalimide, respectively:
EXAMPLE 23A ##STR204##
Example 23A: HRMS (FAB, M+H + ): m/e calc'd for C 29 H 35 N 4 O 2 SCl 2 ! + : 573.1858, found 573.1845.
EXAMPLE 23B ##STR205##
Example 23B: HRMS (FAB, M+H + ): m/e calc'd for C 31 H 32 N 3 O 4 Cl 2 2 ! + : 580.1770, found 580.1771.
EXAMPLE 24 ##STR206##
Treat the product of Example 22, Step 4 (0.18 g) with HOBT (54 mg)and 3,5-bis-trifluorobenzoic acid (0.13 g) in CH 2 Cl 2 (40 mL) at 0° C. To this cooled mixture add DEC (76 mg) and stir for a further 18 h. Wash the solution with H 2 O (20 mL), dry the organic layer over MgSO 4 , filter and evaporate give a foam. Purify the crude product by silica gel chromatography eluting with mixtures NH 3 /MeOH/CH 2 Cl 2 to give the title compound (0.18 g). Analysis: Calc'd for C 32 H 30 N 2 O 4 Cl 2 F 6 . 1.5H 2 O; C, 53.49, H, 4.63,N, 3.90. Found: C, 53.39, H, 4.31,) N, 3.78.
EXAMPLE 25 ##STR207##
Step 1: Add the product of Example 22, Step 4 (1.8 g) and TFA (0.31 μL) to a iodoxybenzoic acid (2.24 g) in DMSO (20 mL). Stir the mixture for 2 h and add ice/H 2 O (50 mL), conc. NH 4 OH soln. (5 mL) and EtOAc (50 mL). Stir the mixture and filter to remove solids. Wash the solid residue with H 2 O (2×20 mL) and EtOAc (2×20 mL). Combine the filtrates, separate the organic layer and wash with H 2 O (2×25 mL), dry over MgSO 4 , filter and evaporate to give 3-(3,4-dichlorophenyl)-5-(4-hydroxy-4-phenyl-1 -piperidinyl)-2-(2-methoxyimino)pentanal (1.8 g) as a foamy solid. Mass spectrum (FAB): 449.
Step 2: Treat the product of Step 1 (0.2 g) in CF 3 CH 2 OH (5 mL) with 3Å molecular sieves (1.0 g) and 3,5-bistrifluoromethylbenzylamine (0.14 g). Stir the mixture for 90 min. and add NaBH 3 CN (0.12 g). After 18 h. filter the reaction mixture through a pad of celite, rinse the celite with MeOH (10 mL) and evaporate the combined filtrates. Partition the residue between CH 2 Cl 2 (15 mL) and 20% KOH (15 mL). Separate the organic layer and extract the aqueous layer with CH 2 Cl 2 (2×20 mL). Combine the organic extracts, dry over MgSO 4 , filter and evaporate to give a solid. Purify the crude by silica gel chromatography eluting with NH 3 /MeOH/CH 2 Cl 2 mixtures to give the title compound (0.1 g)
HRMS (FAB, M+H + ): m/e calc'd for C 32 H 34 N 3 O 6 Cl 2 F 6 ! + : 676.1932, found 676,1 940.
EXAMPLE 25A
3-(3,4-Dichlorophenyl)-5-(4-hydroxy-4-phenyl-1 -piperidinyl)-1 - (2-methoxyphenyl)methyl!amino!-2-pentanone O-methyloxime.
Using the product of Example 25, Step 1 as starting material, prepare the compound of Example 25A using 2-methoxybenzylamine in a procedure similar to that described in Example 25, Step 2.
HRMS (FAB, M+H + ): m/e calc'd for C 31 H 37 N 3 O 3 Cl 2 ! + : 570.2290, found 570.2291
EXAMPLE 26 ##STR208##
Treat the product of Example 25A (50 mg) in CH 2 Cl 2 (5 mL) with HOBT (12.4 mg) and AcOH (1 mL) and cool to 0° C. To the cold solution, add DEC (17.6 mg) and stir for a further 18 h. Wash the reaction mixture with 10% NH 4 OH soln. (3 mL). Reextract the aqueous layer with CH 2 Cl 2 (3×3 mL), combine the organic portions, dry over MgSO 4 , filter and evaporate to give a solid. Purify the crude by silica gel chromatography eluting with NH 3 /MeOH/CH 2 Cl 2 mixtures to give the title compound (0.042 g).
Analysis: Calc'd for C 33 H 39 N 3 O 4 Cl 2 . 0.5H 2 O; C, 63.76, H, 6.49, N, 6.76. Found: C, 63.83, H, 6.85, N, 6.95.
EXAMPLE 27 ##STR209##
Treat the product obtained in Preparation 5A in a similar manner to the procedures described in Preparation 4 and Example 1 to obtain the desired product.
HRMS (FAB, M+H + ): m/e cal'd for C 33 H 36 N 3 O 2 Cl 2 F 6 ! + : 690.2089, found 690.2085.
EXAMPLE 28 ##STR210##
Dissolve the product of Preparation 9 in anhydrous CH 3 OH, filter, add 0.82 g (4.6 mmol) of 4-phenyl-4-hydroxypiperidine and 1.1 g of MgSO 4 , and stir 30 min at room temperature. Add NaCNBH3 (0.40 g, 6.38 mmol) and stir at room temperature under N 2 for 15 h. Filter and evaporate in vacuo. Partition the residue between CH 2 Cl 2 (150 ml) and H 2 O. Wash the organic layer with brine, dry (MgSO 4 ), filter and evaporate in vacuo (1.90 g). Purify by flash chromatography (50 g SiO 2 ; eluant:hexane:EtOAc (70:30)) to obtain 1.06 g (61.63%) of the crystalline hemihydrate of the title compound. M.p. 115°-118° C. FAB-Ms.: m/z 675 ( C 33 H 34 35 Cl 2 F 6 N 2 O 2 +H! + , 100%). Maleate hemihydrate m.p.56°-60°.
Use the appropriate aldehyde from Preparation 9 and the appropriate amine in the procedure of Example 28 to obtain the compounds shown in the following table:
__________________________________________________________________________ ##STR211##Ex. Z b T Isomer Physical Data__________________________________________________________________________28A ##STR212## 2 ##STR213## Z maleate.1/2 H.sub.2 O: m.p. 61-65° C.28B ##STR214## 2 ##STR215## E dimaleate: m.p.: 193-195.5° C.28C ##STR216## 1 ##STR217## E FAB-Ms: m/z 661 ( C.sub.32 H.sub.32.sup.35 Cl.sub.2 - F.sub.6 N.sub.2 O.sub.2 + H!.sup.+, 100%).28D ##STR218## 1 ##STR219## E maleate.1/2 H.sub.2 O: m.p.: 126-130.degre e. C.28E ##STR220## 1 ##STR221## E maleate: m.p.: 153-156° C.28F ##STR222## 1 ##STR223## Z maleate.H.sub.2 O: m.p. 70-73°__________________________________________________________________________ C.
EXAMPLE b 29 ##STR224## Step 1: Treat the product of Preparation 3 (0.469 g) in a solution of THF (1 mL) and DMF (1 mL) at 0° C. with NaH (50 mg), stir for 15 min., then add benzyl bromide (0.145 mL). Stir the resulting mixture for 18 h , evaporate the solvent under reduced pressure and partition the residue between CH 2 Cl 2 (50 mL) and H 2 O (50 mL). Separate the organic layer, wash with brine (50 mL) dry over MgSO4, filter and evaporate. Purify the product by silica gel chromatography eluting with NH 3 /MeOH/CH 2 Cl 2 mixtures to give α- phenylmethoxy!methyl!-β-(3,4-dichlorophenyl)-4-hydroxy-4-phenyl-1-piperidinol (0.2 g).
Step 2: Oxidize the product of Step 1 (0.1 g) according to the procedure of Preparation 4 to give 1- phenylmethoxy!methyl!-3-(3,4-dichlorophenyl)-5-(4-hydroxy-4-phenyl-1-piperidinyl)-2-pentanone (0.178 g).
Step 3: Treat the product of Step 2 (0.16 g) with O-methoxylamine HCl as in the procedure of Example 1 to obtain the title compound (0.14 g). HRMS (FAB, M+H + ): m/e calc'd for C 30 H 35 N 2 O 3 Cl 2 ! + : 541.2025, found 541.2018
Using the product of Preparation 3 and the appropriate halide, prepare the compounds of Examples 29A to 29K, shown in the following tables, using a procedure similar to that described in Example 29:
__________________________________________________________________________ ##STR225## HRMS calc'd (FAB, HRMSEx. T Starting Material M + H.sup.+) Found__________________________________________________________________________29A##STR226## ##STR227## 591.2181 591.216129B##STR228## ##STR229## 589.2036 589.202929C##STR230## ##STR231## 555.2181 555.218629D##STR232## ##STR233## 555.2181 555.217029E##STR234## ##STR235## 559.1931 559.193129F##STR236## ##STR237## 559.1931 559.192529G##STR238## ##STR239## 559.1931 559.192529H##STR240## ##STR241## 571.2130 571.2145__________________________________________________________________________ Analysis AnalysisEx. T Starting Material Calc'd Found__________________________________________________________________________29I##STR242## ##STR243## C, 60.35; H, 6.21; N, 4.54 C.sub.31 H.sub.36 N.sub.2 - O.sub.4 Cl.sub.2.HCl , 0.5H.sub.2 O! C, 60.32; H, 6.23; N, 4.6329J##STR244## ##STR245## C, 64.64; H, 6.39; N, 4.86 C.sub.321 H.sub.36 N.sub.2 - O.sub.4 Cl.sub.2.0.2 5 H.sub.2 O! C, 64.61; H, 6.41; N, 4.8929K##STR246## ##STR247## C, 61.36; H, 6.49; N, 4.34 C.sub.33 H.sub.40 N.sub.2 - O.sub.6 Cl.sub.2.0.8 H.sub.2 O! C, 61.43; H, 6.40; N,__________________________________________________________________________ 4.38
EXAMPLE 30 ##STR248##
Step 1: Using the procedure of Example 29, replace O-methoxylamine HCl with hydroxylamine in Step 3 obtain 2- 2-(3,4-dichlorophenyl)-1- (3,5-dimethoxyphenyl)methoxy!methyl!-4-(4-hydroxy-4-phenyl-1 -piperidinyl)-2-pentanone oxime.
Step 2: Treat the product of Step 1 (0.40 g) in DMF (10 mL) at 0° C. with NaH (55 mg) then methylbromoacetate (0.115 g). Stir the mixture and allow to warm to room temperature over 2 h. Partition the reaction mixture between EtOAc (50 mL) and H 2 O (15 ml). Separate the organic layer, wash with H 2 O (2×15 mL), dry over MgSO 4 , filter and evaporate. Purify the residue by silical gel chromatography eluting with mixtures of NH 3 /MeOH/CH 2 Cl 2 to give methyl-2- 2-(3,4-dichlorophenyl)-1- (3,5-dimethoxyphenyl)methoxy!methyl!-4-(4-hydroxy-4-phenyl-1 -piperidinyl)butylidene!amino!oxy!acetate (0.32 g).
Step 3: Treat the product of Step 2 with 4% NH 3 /CH 3 OH (10 mL) in a sealed bottle and stir for 3 days at room temperature. Evaporate the solution to dryness and purify by silical gel chromatography eluting with mixtures NH 3 /MeOH/CH 2 Cl 2 to give the title compound (0.25 g). HRMS (FAB, M+H + ): m/e calc'd for C 33 H 39 N 3 O 6 Cl 2 ! + : 644.2294, found 644.2282.
EXAMPLE 31 ##STR249##
Using a procedure similar to that described in Example 8, treat the ketone of Preparation 4 with diethyl methylphosphonoacetate to obtain the title compound as an E/Z mixture. HRMS (FAB, M+H + ): m/e calc'd for C 34 H 34 Cl 2 F 6 NO 4 ! + : 704.1769, found 704.1757.
EXAMPLE 32 ##STR250##
Treat a suspension of (CH 3 OCH 2 )Ph 3 PBr (0.21 g, 0.6 mmol) in dry THF (10 mL) with NaN(TMS) 2 (0.6 mL of a 1.0M solution in THF) at 0° C. After 30 minutes, add the product of Preparation 4 (0.05 g, 0.08 mmol) in dry THF (5 mL) and slowly warm the reaction to room temperature over 1 hour. Stir for 3 hours at room temperature and quench by the addition of water. Extract with CH 2 Cl 2 (3×25 mL). Wash the combined organics with brine, dry (Na 2 SO 4 ) and concentrate. Purify the crude material on two preparative TLC plates (20×20 cm, 0.5 mm thickness) eluting with CH 2 Cl 2 and CH 3 OH saturated with ammonia (98:2) followed by reelution with hexane and 2-propanol (90:10) to provide the product (24 mg, 47%) as a white sticky foam (E/Z mixture). HRMS (FAB, M+H + ): m/e calc'd for C 33 H 34 Cl 2 F 6 NO.sub. ! + : 676.1821, found 1 5 676.1834.
Use the appropriate alkyl-substituted Wittig reagents (alkyl-PPh 3 Br) in the procedure of Example 32, to prepare the following compounds:
______________________________________ ##STR251## HRMS calc'd (FAB, HRMSEx. A M + H.sup.+) Found______________________________________32A CH.sub.2 646.1714 646.173032B CHCH.sub.3 660.1870 660.186432C CHCH.sub.2CH.sub.3 674.2027 674.2013______________________________________
EXAMPLE 33 ##STR252##
Treat the product of Example 31 (0.69 g, 0.98 mmol) in dry CH 2 Cl 2 (30.0 mL) at 0° C. with a solution of DiBAl-H (3.9 mL of a 1M solution in CH 2 Cl 2 ). Warm to room temperature and stir for 15 minutes. Quench by slowly adding saturated aqueous Na 2 SO 4 . Dilute with water and extract with CH 2 Cl 2 (3×50 mL), wash with brine, dry (Na 2 SO 4 ) and concentrate. Purify the crude material on a flash column (100 g SiO 2 ; eluant CH 2 Cl 2 :CH 3 OH saturated with ammonia 95:5) to give the desired product as a white powder (0.52 g, 79%). HRMS (FAB, M+H + ): m/e calc'd for C 33 H 34 Cl 2 F 6 NO 3 ! + : 676.1820, found 676.1815.
EXAMPLE 34 ##STR253##
Treat the product of Example 33 (0.5 g, 0.7 mmol) in dry THF (20 mL) with NaH (0.28 g of a 60% dispersion in mineral oil, 7 mmol) and acetic anhydride (0.36 g, 3.5 mmol) at room temperature and stir for 18 hours. Cool to 0° C. and treat with CH 2 Cl 2 (50 mL) and water (10 mL). Wash the organic layer with water, dry (Na 2 SO 4 ) and concentrate. Purify the crude material on a flash column (SiO 2 ; elute with CH 2 Cl 2 :CH 3 OH saturated with ammonia 95:5) to give the desired product as a white foam (0.42 g, 79%). HRMS (FAB, M+H + ): m/e calc'd for C 35 H 36 Cl 2 F 6 NO 4 ! + : 718.1926, found 718.1922.
Using the product of Example 33 as the starting material and the appropriate electrophile in the procedure of Example 34, the following compounds are prepared:
EXAMPLE 34A ##STR254##
EXAMPLE 34B ##STR255##
EXAMPLES 35, 35A, 35B, 35C
Using the procedures described below, compounds of the following structural formula were prepared, wherein the definitions of A are shown in the table below:
______________________________________ ##STR256## HRMS calc'd (FAB, HRMSEx. A M + H.sup.+) Found______________________________________35 CHCH.sub.2N.sub.3 701.1885 701.188535A CHCH.sub.2NH.sub.2 675.1980 675.197935B CHCH.sub.2N(CH.sub.3).sub.2 703.2293 703.229035C CHCH.sub.2 N (CH.sub.2).sub.2 OH!.sub.2 763.2504 763.2502______________________________________
EXAMPLE 35
Treat the product of Example 34 (0.8 g, 0.11 mmol) in THF/H 2 O (5:2, 4 mL) with NaN 3 (0.036 g, 5 mmol) and Pd(PPh 3 ) 4 (0.013 g, 0.01 mmol) and heat to reflux for 1 hour. Cool to room temperature and dilute with Et 2 O (10 mL). Separate the organic layer and extract the aqueous layer with additional Et 2 O (2×5 mL).Wash the combined organic layers with brine, dry (Na 2 SO4) and concentrate. Purify the crude material on a flash column (SiO 2 ; elute with CH 2 Cl 2 :CH 3 OH saturated with ammonia 95:5) to give the desired product as a white sticky foam (0.039 g, 51%).
EXAMPLE 35A
Treat the product of Example 35 (0.21 g, 0.3 mmol) in THF (20 mL) with Ph 3 P (0.095 g, 0.36 mmol) and water (0.25 mL) at room temperature and stir for 2 hours. Add additional Ph 3 P (0.1 g) and stir for 30 minutes. Concentrate and purify the crude product on a flash column (SiO 2 ; elute with CH 2 Cl 2 :CH 3 OH saturated with ammonia 90:10) to give the desired product as a dark foam (0.11 g, 50%). HRMS (FAB, M+H + ): m/e calc'd for C 33 H 35 Cl 2 F 6 N 2 O 2 ! + : 675.1980, found 675.1979.
EXAMPLE 35B
Use the product of Example 34 as the starting material and dimethylamine in the procedure of Example 35 with THF as the solvent to obtain the desired product.
EXAMPLE 35C
Use the product of Example 34 as the starting material and diethanolamine in the procedure of Example 35 with THF as the solvent to obtain the desired product.
EXAMPLE 36 ##STR257##
Treat the product of Example 1A (0.036 g, 0.05 mmol) with CH 3 I (1 mL) at room temperature and place in the refrigerator for 18 h. Remove the excess CH 3 I under a stream of N 2 . Dissolve the residue in CH 3 OH and add water until turbid. When crystals have formed, remove the solvent with a pipette. Wash the crystals with water and pump dry to give the product as a white solid (0.031 g, 78%) HRMS (FAB, M+H + ): m/e calc'd for C 32 H 33 Cl 2 F 6 N 2 O 3 ! + : 677.1772, found 677.1765.
EXAMPLES 37 to 37E
Using the product of Example 1A in the procedure described in Example 8, reacting with 4-bromobutyronitrile, 5-bromovaleronitrile and 6-bromocapronitrile, respectively, the products of Examples 37 to 37B were obtained; subsequent treatment with hydroxylamine as described in Example 11 resulted in compounds 37C to 37E.
______________________________________ ##STR258## HRMS calc'd (FAB, HRMSEx. A M + H.sup.+) Found______________________________________37 (CH.sub.2).sub.3CN 730.2038 730.202337A (CH.sub.2).sub.4CN 744.2194 744.218937B (CH.sub.2).sub.5CN 758.2351 758.235337C (CH.sub.2).sub.3C(NH.sub.2)NOH 763.2253 763.226337D (CH.sub.2).sub.4C(NH.sub.2)NOH 777.2409 777.239037E (CH.sub.2).sub.5C(NH.sub.2)NOH 791.2566 791.2575______________________________________
EXAMPLE 38 ##STR259##
Step 1: Cool a solution of CH 3 P(O)(OCH 3 ) 2 (0.55 g, 4.4 mmol) in dry THF (10 mL) to -780° C. and add n-BuLi (2.75 mL of a 1.6M solution in hexanes) dropwise. Stir for 45 min at -78° C. and add a solution of 4-(3,4-dichloro-phenyl)glutaric anhydride (0.52 g, 2 mmol) in dry THF (5 mL). Stir for 2 hours at -78° C. and quench by adding 1N HCl (15 mL). Extract with EtOAc (3×25 mL), wash the combined organic layers with brine, dry (Na 2 SO 4 ) and concentrate. Purify the crude material on a flash column (100 g SiO 2; elute with EtOAc:CH 3 OH:HOAc 90:10:2) to give an oil (0.55 g, 75%).
Step 2: Add K 2 CO 3 (1.0 g, 7.2 mmol) to a solution of the product of step 1 (2.0 g, 5.2 mmol) and 3,5-bis(trifluoromethyl)benzaldehyde (1.9 g, 7.9 mmol) in dry CH 3 CN (60 mL) at room temperature. Stir for 5 hours and filter the crude reaction mixture through filter paper. Concentrate and purify the crude reaction through a flash column (SiO 2 ; elute with EtOAc: CH 3 OH: HOAc 90:10:2) to give a white solid (2.0 9, 77%).
Step 3: React the product of step 2 (5.8 g, 11.6 mmol) with H 2 gas (balloon) in the presence of 10% Pd/C (0.58 g, 10% w/w) for 3 hours at room temperature. Pass the crude reaction through a short pad of silica gel eluting with EtOAc to give 3.7 g of product (64%) to be used directly in the next step.
Step 4: Treat a cooled (0° C.) solution of 4-phenyl-4-hydroxypiperidine (1.6 g, 8.9 mmol) in DMF (50 mL) with 4-methylmorpholine (0.89 g, 8.9 mmol), HOBT (1.0 g, 7.4 mmol) and the product of step 3 (3.7 g, 7.4 mmol). Stir at 0° C. for 30 min and room temperature for 6 h. Concentrate and dilute the residue with 1:1 water:EtOAc (200 mL). Wash the organic layer with brine, dry (Na 2 SO 4 ) and concentrate. Purify the crude reaction product on a flash column (SiO 2 ; elute with EtOAc: hexane 4:5) to give a white foam (1.45 g, 35%).
Step 5: Treat a solution of the product of step 4 (0.5 g, 0.75 mmol) in pyridine (30 mL) with CH 3 ONH 2 ·HCl (0.1 g, 1.2 mmol) and heat to 60° C. for 1.5 hours. Concentrate and purify the residue on a flash column (SiO 2 ; elute with CH 2 Cl 2 :CH 3 OH saturated with ammonia 95:5) to give the title compound (0.52 g, 99%) as a white solid and a mixture of E and Z oxime isomers.
Step 6: Treat a solution of the product of step 5 (0.2 g, 0.29 mmol) in CH 2 Cl 2 (15 mL) at 0° C. with DiBAl-H (64 μL of a 1M solution in CH 2 Cl 2 ). After 10 minutes, quench by the addition of saturated aqueous Na 2 SO 4 , dry by the addition of solid Na 2 SO 4 and concentrate. Purify the crude material on two preparative TLC plates eluting with CH 2 Cl 2 :CH 3 OH saturated with ammonia 95:5 to give the title compound (0.027 g, 14% of oxime isomer A and 0.046 g, 24% of oxime isomer B). Isomer A: HRMS (FAB, M+H + ): m/e calc'd for C 33 H 35 Cl 2 F 6 N 2 O 2 ! + : 675.1980, found 675.1986. Isomer B: HRMS (FAB, M+H + ): m/e calc'd for C 33 H 35 Cl 2 F 6 N 2 O 2 ! + : 675.1980, found 675.1986.
EXAMPLE 39
The compounds described in Examples 39 to 39N are prepared in a similar manner to that described in Example 20, using the appropriate oxime and the appropriate amine:
__________________________________________________________________________ ##STR260## HRMS HRMS (FAB, M + H.sup.+) (FAB, M + H.sup.+)ExampleZ R.sup.1 Calculated Found__________________________________________________________________________39 ##STR261## (CH.sub.2).sub.2 OH 734.1987 734.200139A ##STR262## H 654.2089 654.208239B ##STR263## (CH.sub.2).sub.2 OH 698.2351 698.234939C ##STR264## CH.sub.2 CN 729.1834 729.13439D ##STR265## ##STR266## 762.2049 762.204239E ##STR267## CH.sub.2 CN 693.2198 693.220639F ##STR268## ##STR269## 726.2412 726.241239G ##STR270## H 683.1990 683.199339H ##STR271## CH.sub.2 CN 722.2099 722.208839I ##STR272## ##STR273## 755.2314 755.230539J ##STR274## (CH.sub.2).sub.2 OH 727.2253 727.222939K ##STR275## H 682.2038 682.204239L ##STR276## CH.sub.2 CN 721.2147 721.213639M ##STR277## ##STR278## 754.2362 754.237139N ##STR279## (CH.sub.2).sub.2 CN 726.2300 726.2283__________________________________________________________________________
EXAMPLES 40 and 40A ##STR280##
EXAMPLE 40
R 2 is --C(O)NH 2
Reflux the product of Preparation 4 (52 mg) in EtOH (1.5 mL) with semicarbazide HCl (75 mg) and KOAc (75 mg) for 1 h. Extract the resultant mixture with water, NaHCO 3 and CH 2 Cl 2 , dry the organic layer and evaporate to obtain a white foam. MASS (FAB, M+H + ) m/e 705.
EXAMPLE 40A
R 2 is --C(O)CH 3
Reflux the product of Preparation 4 (42 mg) in EtOH (1.5 mL) with acetylhydrazide (80 mg) and HOAc (25 mg) for 1 h. Extract as in Example 40 and isolate the product by preparative TLC on silica gel, eluting with CH 2 Cl 2 :CH 3 OH (12:1) to obtain the desired compound as a foam. MASS (FAB, M+H + ) m/e 704
EXAMPLE 41 ##STR281##
Step 1: 3-(3,4-dichlorophenyl)-dihydro-2(3H)-furanone
Heat (CH 3 ) 3 Si! 2 NLi (230 ml, 1.0M in THF) under N 2 to 45° C. and add 3,4 dichlorophenyl acetic acid methyl ester (40 g, 0.183 moles) dissolved in 60 ml of dry THF dropwise over 2 h. Stir the solution at 45° C. for another 2.5 h. Cool the solution to room temperature, add a dry THF solution (30 ml.) of THP-protected Br(CH 2 ) 2 OH dropwise over 1 h., and stir the solution for 24 h. Cool the solution in an ice bath and quench the reaction by adding, dropwise, 250 ml. of 1.0M aqueous HCl. Extract the solution with Et 2 O, wash the organic layer twice with 1.0M aqueous HCl, then with water, and dry over anhydrous Na 2 SO 4 . Remove the solvent, dissolve the residue in CH 3 OH and add 0.5 g of pTSA. Stir the solution at room temperature overnight, remove the solvent, add CH 3 OH (500 ml) and stir for 6 h. Remove the solvent again, add more CH 3 OH (500 ml.), stir overnight and remove the solvent. Dissolve the resulting oil in CH 2 Cl 2 (1200 ml.), wash twice with saturated aqueous NaHCO 3 , then water, and dry over anhydrous Na 2 SO 4 . Remove the solvent in vacuo. Purify the reaction mixture by flash chromatography (SiO 2 ) using EtOAc: hexanes (3:7) as eluent. Yield: 22 g. Cl-MS: 231 (100%), 233 (65%).
Step 2: alpha-(2-bromoethyl)-3,4-dichlorophenylacetic acid
Treat the product of Step 1 (21.25 g, 91.96 mmoles) at room temperature with 130 ml. of HOAc saturated with HBr gas. Stir at room temperature for 2 days, then pour into 800 ml. of ice-water with stirring. Store the resultant gum in a freezer for two days, then decant the liquid from the solidified gum. Triturate the solid, filter, wash with water and air dry. Yield: 26.2 g (m.p.=80°-81° C.).
Step 3: alpha-(2-bromoethyl)-3,4-dichlorophenylacetic acid chloride
Dissolve the product of Step 2 (8.1 g, 25.96 mmoles) in 20 ml. of dry CH 2 Cl 2 . Add oxalyl chloride (8.1 g, 62.3 mmoles), followed by 50 μl of dry DMF and heat the solution to reflux for 3 h. Cool the solution to room temperature and remove the solvent and excess reagent using reduced pressure. Yield: 8.2 g (IR: 1785 cm -1 ).
Step 4: 5-bromo-1-diazo-3-(3,4-dichlorophenyl)--2-pentanone
Prepare a solution of diazomethane from 15 g of MNNG by reaction with 45 ml of 40% aqueous KOH topped with 150 ml. of Et 2 O and cool in an ice bath. Add an Et 2 O solution (40 ml.) of the product of Step 3 (8.2 g, 5 24.8 mmoles) in small volumes, stir the solution in the ice bath for 15 min, then heat to reflux for 30 min. Remove the solvent in vacuo. Purify the resulting mixture by flash chromatography on silica gel using CH 2 Cl 2 as eluent. Yield: 7.0 g (IR: 2100 cm -1 , 1630 cm -1 ).
Step 5: 1-diazo-3-(3,4-dichlorophenyl)-5-(4-hydroxy-4-phenyl-1-piperidinyl)-2-pentanone
Dissolve the product of Step 4 (3.93 g, 11.7 mmoles) in 50 ml of dry EtOAc. Add 4-hydroxy-4-phenyl-1-piperidine (2.55 g, 14.4 mmoles), followed by dry Et 3 N (13.3 ml.). Heat under N 2 at 60°-65° C. for 28 h. Cool to room temperature, filter the solid and wash with EtOAc. Apply the filtrate 1 5 to a silica gel column and elute the column with 1.5% CH 3 OH(NH 3 )/EtOAc. Yield: 2.34 g; Cl-MS: m/e=432 (M+H + , 35 Cl+ 37 Cl isotope).
Step 6: 3-(3,4-dichlorophenyl)-1- (3,5-dimethylphenyl)methoxy!-5-(4-hydroxy-4-phenyl-1-piperidinyl)-2-pentanone
Dissolve 3,5-dimethyl benzyl alcohol (1.32 g, 9.71 mmoles) in 4.0 ml of dry CH 2 Cl 2 and add BF 3 etherate (0.44 ml, 3.56 mmoles). Add a dry CH 2 Cl 2 solution (2.0 ml.) of the product of Step 5 (0.7 g, 1.62 mmoles) dropwise at room temperature, under N 2 , over a period of 4.5 h. Stir the mixture at room temperature for another 30 min, then quench the reaction with water (6.0 ml) followed, after 10 min of stirring, by Et 3 N (2.0 ml). Stir for 15 min, then dilute with 90 ml of CH 2 Cl 2 . Wash the organic layer with water and dry it over anhydrous Na 2 SO 4 . Purify the reaction mixture by flash chromatography (SiO 2 ), eluting the column first with 30% EtOAc/hexanes, then, after elution of the excess of 3,5-dimethyl benzyl alcohol, change the eluent to 40% EtOAc/Hexanes. Yield: 0.435 g. HRMS (FAB, M+H + ): m/e calc'd for C 31 H 36 NO 3 Cl 2 ! + : 540.2072; found 540.2075.
Step 7: Add methoxylamine HCl (75 mg, 0.9 mmoles) to the product of Step 6 (0.32 g, 0.59 mmoles) dissolved in 3.0 ml of dry pyridine. Heat the solution under N 2 , at 60°-65° C. for 90 min, then remove the pyridine in vacuo. Purify the reaction mixture by preparative TLC, eluting the silica gel plates with EtOAc:Hexanes:CH 3 OH(NH 3 ) (25:75:2.5). Extract the title compound with MeOH(NH 3 ):EtOAc (5:95). Yield: 0.209 g. HRMS (FAB, M+H + ): m/e calc'd for (C 32 H 39 N2O 3 Cl 2 ! + : 569.2338; found 569.2335.
Examples 41A to 41P are prepared from the product of Example 41, Step 5, by reaction with suitable alcohols or mercaptans using a procedure similar to the one described for Example 41, Step 6. The resulting ketones are reacted with methyloxime hydrochloride using a 5 procedure similar to the one described in Example 41, Step 7.
______________________________________ ##STR282##Ex. ##STR283## HRMS calc'd (FAB M + H.sup.+) hrms Found______________________________________41A ##STR284## 601.2236 601.223041B ##STR285## 609.1245 609.124741C ##STR286## 547.2494 547.248741D ##STR287## 625.1670 625.166441E ##STR288## 611.1514 611.151141F ##STR289## 583.2494 583.248741G ##STR290## 691.1929 691.193241H ##STR291## 577.1836 577.184341I ##STR292## 627.1804 627.180941J ##STR293## 617.2338 617.232941K ##STR294## 599.2807 599.281041L ##STR295## 599.2807 599.281041M ##STR296## 623.1402 623.139341N ##STR297## 697.0235 697.024341O ##STR298## 587.2807 587.2810______________________________________
EXAMPLE 42 ##STR299##
Step 1: Methyl 3-(3,4-dichlorophenyl)-3- 2-(ethoxycarbonyl)-2-(1 ,3-dithiolanyl)!-propanoate
Dissolve (CH 3 ) 3 Si! 2 NLi (171.0 mL of 1.0M solution, 0.171 mol) in dry THF (170 mL), cool to -78° C. under N 2 , add ethyl 1,3-dithiolane-2-carboxylate (33.2 g, 0.186 mol) in dry THF (120 mL) dropwise and stir at -78° C. for 20 mins. Add methyl 3,4-dichlorocinnamate (34.8 g, 0.150 mol) in DMPU (180 mL) dropwise. Stir at -78° C. for 5 h. Add CH 3 OH (30 mL), warm to -30° C. and add saturated aqueous NH 4 Cl (500 mL) and water (500 mL). Extract with EtOAc (3×400 mL), dry combined organic extracts (MgSO 4 ), filter and concentrate. Purify by chromatography (2.5 L of flash silica gel; eluant: 5% EtOAc-hexane then 15% EtOAc-hexane). Combine appropriate fractions and concentrate to give 53.6 g (0.131 mol, 87%) of the title compound as a colorless oil. MS (FAB): m/e 409 (M+1)
Step 2: 2-(Hydroxymethyl)-2- 3- 3-(3,4-dichlorophenyl)-1-hydroxy!-propyl!-1,3-dithiolane
Dissolve the product (75.10 g, 0.183 mol) of Step 1 in dry THF (700 mL), cool to 0° C. under N 2 , add LiAlH 4 (275 mL of 1.0M in Et 2 O, 0.275 mol) dropwise and stir at 0° C. for 30 mins, then at 23° C. for 16 h. Add water (10 mL) dropwise followed by 25 wt % NaOH (10 mL). Dilute with CH 2 Cl 2 (500 mL) and filter through celite. Extract celite with CH 2 Cl 2 via a soxhlet extractor. Concentrate combined organic solutions and triturate with hexane to give 56.8 g (0.167 mol, 92%) of the title compound as a white solid (mp=122°-124° C.). MS (FAB): m/e 339 (M+1)
Step 3: 2-(Hydroxymethyl)-2- 3- 3-(3,4-dichlorophenyl)-1- dimethyl(1,1-dimethylethyl)silyloxy!!-propyl!-1,3-dithiolane
Dissolve the product (67.80 g, 0.200 mol) of Step 2 in dry THF (1300 mL), add Et 3 N (30.30 g, 41.8 mL, 0.300 mol) and dimethylamino-pyridine (4.90 g, 0.040 mol) and cool to 0° C. under N 2 . Add t-butyl-dimethylsilyl chloride (36.14 g, 0.240 mol) in dry THF (200 mL) dropwise. Warm slowly to 23° C. and stir for 72 h. Add water (1000 mL), extract with EtOAc, dry combined organic extracts (MgSO 4 ), filter, and concentrate. Purify by chromatography (2.0 L of flash silica, eluant 1:2 EtOAc:hexane). Combine appropriate fractions and concentrate to give 89.4 g (0.197 mol, 99%) of the title compound as a colorless oil. MS (FAB): m/e 453 (M+t)
Step 4: 2- 3,5-Bis(trifluoromethyl)phenyl!methoxymethyl!-2- 3- 3-(3,4-dichlorophenyl)-1- dimethyl(1,1-dimethylethyl)silyloxy!!-propyl!-1,3-dithiolane
Dissolve the product (89.40 g, 0.197 mol) of Step 3 in dry THF (1 L), cool to 0° C. under N 2 , add (CH 3 ) 3 Si! 2 NK (434 mL of 0.5M solution, 0.217 mol) dropwise. Add 3,5-bis(trifluoromethyl)benzyl bromide (75.65 g, 45.2 mL, 0.246 mol), stir at 0° C. for 30 mins, then warm slowly to 23° C. Reflux for 16 h, then cool to 23° C. Add saturated aqueous NH 4 Cl (500 mL) and water (500 mL), extract with EtOAc, dry combined organic extracts (MgSO 4 ), filter, and concentrate. Purify by chromatography (3.0 L flash silica, eluant: 10% CH 2 Cl 2 -hexane, 20% CH 2 Cl 2 -hexane, then 25% CH 2 Cl 2 -hexane). Combine appropriate fractions and concentrate to give 105.5 g (0.155 mol, 79%) of a yellow oil. MS (FAB): m/e 547 (M+1)
Step 5: 2-(Hydroxymethyl)-2- 3- 3-(3,4-dichlorophenyl)-1- dimethyl(1,1-dimethylethyl)silyloxy!!-propyl!-1,3-dithiolane
Dissolve the product (80.30 g, 0.118 mol) of Step 4 in CH 3 CN (750 mL) and add 48% aqueous HF (55.2 mL, 1.53 mol), stir at 23° C. for 16 h, concentrate and add water (300 mL). Add 2.0N NaOH until pH is 3-4 and then add saturated aqueous NaHCO 3 . Extract with CH 2 Cl 2 , wash combined organic extracts with saturated aqueous NaCl, dry (MgSO 4 ), filter, and concentrate to give 66.7 g (0.118 mol, 100%) of a yellow oil.
Step 6: 1- 3,5-Bis(trifluoromethyl)phenyl!methoxy!-3-(3,4-dichloro-phenyl)-5-hydroxy-2-pentanone
Dissolve the product (99.8 g, 0.176 mol) of Step 5 in THF (1000 mL) and water (1 05 mL), add CaCO 3 (44.10 g, 0.440 mol), stir for 5 mins, then add Hg(ClO 4 ) 2 (159.7 g, 0.352 mol) in water (185 mL) dropwise. Stir the resultant white precipitate at 23° C. for 5 h, filter, wash the solid with water and EtOAc. Separate layers of filtrate and extract with EtOAc. Wash combined organic extracts with saturated aqueous NaCl, dry (MgSO 4 ), filter, and concentrate to give 86.1 g (0.176, 100%) of the title compound as a yellow oil. MS (FAB): m/e 471 (M+1--H 2 O)
Step 7: 1- 3,5-Bis(trifluoromethyl)phenyl!methoxy!-3-(3,4-dichloro-phenyl)-5-hydroxy-2-pentanone O-methyloxime
Dissolve the product (86.1 g, 0.176 mol) of Step 6 in EtOH (840 mL) and water (165 mL), add CH 3 CO 2 Na (72.2 g, 0.881 mol) and CH 3 ONH 2 HCl (44.12 g, 0.528 mol). Reflux for16 h, cool to 23° C. and concentrate. Add water (800 mL), extract with CH 2 Cl 2 , treat organic extracts with charcoal and MgSO 4 , filter, and concentrate. Purify by chromatography (2.0 L of flash silica, eluant: 1:1 CH 2 Cl 2 :hexane then 1:1 EtOAc:hexane). Combine appropriate fractions and concentrate to give 67.6 g (0.130 mol, 74%) of the title compounds as a yellow oil. The E and Z oxime isomers can be separated by chromatography (10.0 g of mixture on 1.5 L of flash silica; eluant: 10% EtOAc-hexane, 20% EtOAc-hexane, then 30% EtOAc-hexane; gives 6.57 g of desired Z isomer). MS (FAB): m/e 518 (M+1)
Step 8: 1- 3,5-Bis(trifluoromethyl)phenyl!methoxy!-3-(3,4-dichloro-phenyl)-4-formyl-2-butanone O-methyloxime
Dissolve oxalyl chloride (2.01 g, 15.82 mmol) in dry CH 2 Cl 2 (30 mL) and cool to -78° C. under N 2 , add DMSO (2.47 g, 31.64 mmol) in dry CH 2 Cl 2 (12 mL) dropwise and stir at -78° C. for 15 mins. Add the product of Step 7 (6.56 g, 12.66 mmol) in dry CH 2 Cl 2 (20 mL) dropwise and stir at -78° C. for 3 h. Add diisopropylethylamine (4.91 g, 37.97 mmol) and stir at -78° C. for 1 h. Warm slowly to 0° C. and stir at 0° C. for 30 mins. Add water (150 mL) and extract with CH 2 Cl 2 . Wash combined organic extracts with saturated aqueous NaCl, dry (MgSO 4 ), filter, and concentrate to give 6.53 g (12.66 mmol, 100%) of a yellow oil. MS (FAB): m/e 516 (M+1).
Step 9: Dissolve the product (1.05 g, 2.03 mmol) of Step 8 and 4-phenylamino-piperidine (1.08 g, 6.13 mmol) in CF 3 CH 2 OH (10 mL), add crushed 3A sieves (1 g) and NaBH 3 CN (0.26 g, 4.07 mmol), and stir at 23° C. for 4 h. Concentrate and add water (60 mL) and EtOAc (60 mL). Filter through celite, separate layers of filtrate and extract aqueous solution with EtOAc. Dry combined organic extracts (MgSO 4 ), filter and concentrate. Purify by chromatography (200 mL of flash silica gel; eluant:3% CH 3 OH--CH 2 Cl 2 ). Combine appropriate fractions and concentrate to give 0.98 g (1.45 mmol, 66%) of the title compound as a yellow oil. MS (FAB): m/e 676 (M+1)
The following compounds of formula 42A to 42Z are prepared by reacting the product of Example 42, Step 8, with an appropriate amine according to the procedure of Example 42, Step 9:
______________________________________ ##STR300## MS (FAB):Ex. Z m/e______________________________________42A ##STR301## 628 (M + 1)42B ##STR302## 586 (M + 1)42C ##STR303## 682 (M + 1)42D ##STR304## 669 (M + 1)42E ##STR305## 684 (M + 1)42F ##STR306## 668 (M + 1)42G ##STR307## 587 (M + 1)42H ##STR308## 587 (M + 1)42I ##STR309## 704 (M + 1)42J ##STR310## 657 (M + 1)42K ##STR311## 711 (M + 1)42L ##STR312## 682 (M + 1)42M ##STR313## 697 (M + 1)42N ##STR314## 682 (M + 1)42O ##STR315## 712 (M + 1)42P ##STR316## 683 (M + 1)42Q ##STR317## 750 (M + 1)42R ##STR318## 736 (M + 1)42S ##STR319## 670 (M + 1)42T ##STR320## 711 (M + 1)42U ##STR321## 680 (M + 1)42V ##STR322## 712 (M + 1)42W ##STR323## 712 (M + 1)42X ##STR324## 698 (M + 1)42Y ##STR325## 654 (M + 1)42Z ##STR326## 690 (M + 1)______________________________________
EXAMPLE 43 ##STR327##
Dissolve the product (0.380 g, 0.578 mmol) of Example 42J in THF (3 mL) and CH 3 OH (1 mL). Add 1N KOH (2.7 mL, 2.70 mmol) and reflux for 16 h. Cool to 23° C. and add 1N HCl (5 mL) and water (20 mL). Extract with CH 2 Cl 2 (3×20 mL), wash combined organic extracts with saturated aqueous NaCl, dry (MgSO 4 ), filter and concentrate to give 0.312 g (0.496 mmol, 86%) of the title compound as a yellow foam. MS (FAB): m/e 629 (M+1)
EXAMPLE 44 ##STR328##
Dissolve 3-pyrrolidinol (0.033 g, 0.375 mmol) in dry THF (2 mL) and cool to 0° C. under N 2 . Add diisopropylethylamine (0.097 g, 0.13 mL, 0.750 mmol) then add bromoacetyl bromide (0.076 g, 0.033 mL, 0.375 mmol) in dry THF (1 mL). Stir at 0° C. for 30 mins. Add the product (0.20 g, 0.341 mmol) of Example 42B in dry THF (3 mL), warm to 23° C. slowly and stir for 16 h. Concentrate, add water (20 mL), extract with EtOAc, wash combined organic extracts with saturated aqueous NaCl, dry (MgSO 4 ), filter, and concentrate. Purify by chromatography (70 mL of flash silica gel; eluant: 10% CH 3 OH--CH 2 Cl 2 then 20% CH 3 OH--CH 2 Cl 2 ). Combine appropriate fractions and concentrate to give 0.118 g (0.165 mmol, 49%) of the title compound as a yellow oil.MS (FAB): m/e 713 (M+1).
Using the appropriate amine in the procedure of Example 44, the following compounds of formula 44A and 44B are prepared:
EXAMPLE 44A ##STR329##
EXAMPLE 44B ##STR330##
EXAMPLE 45 ##STR331##
Treat a suspension of sarcosine methyl ester hydrochloride (6.02 g,43 mmole) in CH 2 Cl 2 (250 ml) at 0° C. with 3,5-bistrifluoromethyl benzoyl chloride (7.7 ml, 42.5 mmole) and Et 3 N (12.5 ml, 89.7 mmole). Stir the mixture at 20° C. for 1 h. Add water (150 ml) to the mixture and separate the organic layer. Dry (MgSO 4 ) and concentrate the organic layer to give crude product. Purify by silica gel chromatography (eluant: EtOAc:hexane (6:4)) to obtain 12 g (81%). ##STR332##
Treat a solution of 3,4-dichlorolphenyl acetic acid (4.15 g, 20 mmole) in anhydrous THF (50 ml) at -60° C. with (CH 3 ) 3 Si! 2 NLi (46.2 ml, 46.2 mmole) and slowly warm the mixture to 0° C. for 4 h. Transfer this solution to a solution of the product of Step 1 (5.46 g, 16 mmole) in anhydrous THF (8 ml) at -30° C. Warm the reaction to -10° C. over 1 h, stir at 0° C. for 1 h and at 20° C. for 4h. Add 50% of aqueous HOAc (15 ml) and extract with EtOAc twice. Separate the organic layer, dry (MgSO 4 ) and concentrate to give the crude product. Purifiy by silical gel chromatography (eluant: hexane/EtOAc, 6:4) to give 5.21 g (69%) of the product. HRMS (FAB, M+H + )=m/e calc'd for C 19 H 14 NO 2 Cl 2 F 6 ! + =472.0306, found 472.0306 ##STR333##
Treat a solution of the product of Step 2 (0.96 g, 2 mmole) in THF (6 ml) at -78° C. with (CH 3 ) 3 Si! 2 NLi (2.5 ml, 2.5 mmole) and stir at -78° C. for 25 h. Add a solution of 1-bromo-3-methyl-2-butene (0.42 g) in THF (1 ml) to the above anion solution at -78° C., slowly warm the solution to 0° C. and stir at 20° C. for 2 h. Add saturated NH 4 Cl solution (5 ml), extract with EtOAc twice wash the combined EtOAc extracts with brine, dry (MgSO 4 ) and concentrate to give a crude product. Purify by column chromatography (silica gel; eluant: EtOAc:hexane, 2:8) to obtain 1 g of product (87%). MS (FAB, M ++ ) m/e 540. ##STR334##
Treat a solution of the product of Step 3 (0.22 g, 0.4 mmole) in pyridine (3 ml) at 70° C. with methoxyamine HCl (95 mg, 1.14 mmole), stir at 70° C. for 6.5 h and then cool to 20° C. Add water to the reaction mixture, extract the solution with EtOAc, dry (MgSO 4 ) and concentrate the EtOAc extracts to give the crude product. Purify by silica gel chromatography (eluant: hexane:Et 2 O, 1:1) to give 74 mg (32%) of Z-isomer and 130 mg (56%) of E-isomer oximes. MS (FAB, M+H + )=m/e 569. ##STR335##
Treat the product of Step 4 (0.387 of E-isomer, 0.68 mmole) in a solution of EtOAc saturated with O 3 (7.5 ml) at -78° C. for 5 min. Purge the solution with N 2 , add (CH 3 ) 2 S (1.5 ml) and warm the solution from -78° C. to 20° C. over 1 h. Concentrate the solution to give the desired aldehyde which is used directly in the next reaction without further purification. MS (FAB.M +H + )=m/e 543.
Step 6: Treat the product of Step 5 with 4-hydroxy-4-phenylpiperidine in a procedure similar to that described in Example 42, Step 9, to obtain the title compound in overall 77% yield. HRMS(FAB,M + H + )=m/e calc'd for c33H34N3O3Cl2F6! + :704.1881, found 704.1875.
EXAMPLE 46 ##STR336##
By following a procedure similar to that of Example 45, using the appropriate reagents, the title compound is prepared. HRMS(FAB, M+H + )=m/e calc'd for C 33 H 34 N 2 O 3 Cl 2 F 6 ! + =691.192, found 691.1938.
EXAMPLE 47 ##STR337##
Step 1: Stir a solution of 2-chloro-N-methyl-N-methoxy acetamide (28.2 g, 205 mmol), 3,5-bistrifluoromethyl benzyl alcohol (50.0 g, 205 mmol, 1 eq) and CsCO 3 (134 g, 416 mmol) in dry DMF (410 mL) for 20 h. Pour into 1 L Et 2 O+500 mL hexane+500 mL water. Extract the water layer with 2×1 L Et 2 O, combine the organic layers, wash with water (2×500 mL) followed by brine (500 mL). Dry over MgSO 4 , concentrate in vacuo to give 70.2 g (>99%) of the product as a viscous oil.
Step 2: Treat a suspension of Mg turnings (1.8 g) in dry Et 2 O (12 mL) at 30° C. with a-3,4-trichlorotoluene (10.2 mL) in Et 2 O (65 mL) dropwise over 1 h, then stir at 23° C. for 20 min. Add the Grignard reagent dropwise to a solution of the product of step 1 (15.0 g, 43.4 mmol) in 350 mL Et 2 O at -78° C. Stir for 15 min at -78° C., warm to 23° C., pour into 500 mL 0.5N HCI. Extract with Et 2 O, combine organic layers, wash with brine, dry (MgSO 4 ) and concentrate. Triturate the crude product in cold pentane to give 23.3 g of the pure product as a colorless powder.
Step 3: To (CH 3 ) 3 Sl! 2 NNa (67.4 mL, 1.0M in THF) in THF (540 mL) at -78° C., add the product of step 2 (30.0 g, 67.4 mmol) as a solution in 120 mL THF dropwise over 30 min. Stir for 2 h, then, over 30 min, add 2-iodo-N-methoxy-N- methylacetamide (Prepare by stirring a solution of 2-chloro-N-methoxy-N- methylacetamide (10.58 g, 77.6 mmol) and Nal (11.9 g) in 190 mL acetone for 18 h in the dark. Remove the solvent in vacuo, add 300 mL THF and filter the suspension through a pad of Celite. Concentrate the filtrate and dissolve the crude in 80 mL THF.). Allow to warm to 23° C., adding 15 mL saturated NH 4 Cl when the internal temperature reaches 0° C., then concentrate in vacuo. Add 750 mL CH 2 Cl 2 , 1.5 L Et 2 O, and 750 mL water. Wash the organic layer with brine, dry over Na 2 SO 4 , and concentrate. Purify the crude product by filtration through a plug of silica gel using CH 2 Cl 2 /Et 2 O/hexane (1:1:2) as eluent to give 32.4 g, 88% of the product as a viscous oil.
Step 4: Using a procedure similar to that of Example 1, treat the ketone of step 3 to obtain the corresponding oxime methyl ether in 80% yield.
Step 5: Treat a solution of the product of step 4 (2.02 g, 3.5 mmol) in THF (40 mL, -78° C.) with DIBAL (1M in hexane, 10 mL, 10 mmol) for 10 min. Quench the reaction mixture with sat'd. aq. Na 2 SO 4 (2 mL) and allow to warm to room temperature. Dilute the solution with Et 2 O (750 mL), dry (Na 2 SO 4 ) and concentrate to give the crude aldehyde as a colorless oil. The aldehyde is used immediately without any further purification.
Step 6: To a solution of the aidehyde from step 5 (184 mg, 0.36 mmol) in CF 3 CH 2 OH(2 mL) add 4-phenyl-4-piperidinyl acetamide (157 mg, 0.72 mmol), 3 A crushed molecular sieves, and NaBH 3 CN (98 mg, 1.6 mmol). Stir the reaction mixture for 1 h, concentrate and purify by silica gel chromatography (eluent: CH 2 Cl 2 :CH 3 OH:NH 3 aq. (20:1:0.1)) to give the Z isomer of the title compound as a colorless foam. HRMS (FAB, M+H + ): m/e calc'd for C 34 H 36 Cl 2 F 6 N 3 O 3 ! + : 718.2038, found 718.2050.
Using the product of Step 5 and the appropriate amine in the procedure of Step 6, the following compounds are prepared:
______________________________________ ##STR338## MS (FAB):Ex. Z m/e______________________________________47A ##STR339## calc'd: 704.181; found: 704.188647B ##STR340## 669 (M + H.sup.+)47C ##STR341## 651 (M + H.sup.+)47D ##STR342## 666 (M + H.sup.+)47E ##STR343## 697 (M + H.sup.+)47F ##STR344## 735 (M + H.sup.+)47G ##STR345## 677 (M + H.sup.+)47H ##STR346## 693 (M + H.sup.+)47I ##STR347## 651 (M + H.sup.+)______________________________________
EXAMPLE 48
Use the products of Preparations 10 and 11, and others prepared in a similar manner, in the procedure of Example 47 to obtain the following compounds:
__________________________________________________________________________ ##STR348##Ex. Z Q Isomer Physical Data__________________________________________________________________________48 ##STR349## ##STR350## Z MS (Cl/CH.sub.4, M + H.sup.+): 61448A ##STR351## ##STR352## Z MS (FAB M + H.sup.+): 610.248B ##STR353## ##STR354## E/Z mixture MS (FAB M + H.sup.+): 598.148C ##STR355## ##STR356## Z MS (FAB M + H.sup.+): 611.248D ##STR357## ##STR358## Z MS (FAB M + H.sup.+): 659.348E ##STR359## ##STR360## Z MS (FAB M + H.sup.+): 679.348F ##STR361## ##STR362## E/Z mixture MS (FAB M + H.sup.+): 616.448G ##STR363## ##STR364## E/Z mixture MS (FAB M + H.sup.+): 611.048H ##STR365## ##STR366## Z MS (FAB M + H.sup.+): 660.048I ##STR367## ##STR368## Z MS (FAB M + H.sup.+): 650.948J ##STR369## ##STR370## E/Z mixture MS (FAB M + H.sup.+): 614.048K ##STR371## ##STR372## E/Z mixture MS (FAB M + H.sup.+):__________________________________________________________________________ 605.0
EXAMPLE 49 ##STR373##
To a solution of 3,4-dichlorocinnamic acid (5.4 g, 20 mmoles), 4-hydroxy-4-phenylpiperidine (3.6 g, 20.3 mmoles) and Et 3 N (3 mL) in dry THF (100 mL), add a THF suspension of EDCl (3.85 g, 20 mmoles in 30 mL dry THF). After 2 h, add water (100 mL) and extract the product into EtOAc (100 mL). Wash the organic phase with aqueous K 2 CO 3 (50 mL) followed by 0.5M HCl (50 mL). Dry the organic phase (MgSO4) and remove the solvent under reduced pressure. The crude product crystallizes (7.5 g) on standing. HRMS (FAB, M+H + ): m/e calc'd for C 20 H 20 NO 2 Cl 2 ! + : 376.0871, found 376.0856. ##STR374##
Treat a solution of the product of Step 1 (0.5 g, 1.37 mmoles) in CH 3 NO 2 (10 mL) with 1 mL of Triton B (40% benzyltrimethylammonium hydroxide in CH 3 OH). Heat the stirred solution to reflux for 3.5 h. Cool the mixture, neutralize with 1M HCl and dilute with water (30 mL). Extract the product into EtOAc (2×30 mL), dry (MgSO 4 ) and concentrate to an oil. Purify by silica gel chromatography (eluant: EtOAC/Hexane (1:1 to 2:1)) to obtain 0.309 9 of the title compound and 0.160 g starting material. HRMS (FAB, M+H + ): m/e calc'd for C 21 H 23 N 2 O 4 Cl 2 ! + : 437.1035, found 437.1023. ##STR375##
Step 3a: Treat a solution of 3,5-bis(trifluoromethyl)bromobenzene (45.87 g, 0.156 moles) in degassed toluene (300 mL) with allyltributyltin (54.47 g, 0.164 moles) and (C 6 H 5 ) 3 P! 4 Pt (1.8 g, 1.44 mmoles) and reflux for 24 h. Distill the toluene at atmospheric pressure and distill the residue under reduced pressure (10 mm Hg) at 90°-100° C. to afford 23.89 g of the title compound. B.p.: 92°-97° C. at 10 mm Hg. MS (Cl, M+H + ), m/e 255.
Step 3: Treat a THF solution (15 mL) of a mixture of the products of Step 2 (1.8 g, 4.1 mmoles) and Step 3a (2.2 g, 8.6 mmoles) with C 6 H 5 NCO (1.67 g, 14 mmoles), followed by four drops (˜0.05 g) of dry Et 3 N and stir the mixture for 20 h at room temperature under N 2 . Dilute with hexane (5 mL) and filter to remove solids. Concentrate the filtrate to an oil and purify by flash silica gel chromatography (eluant: EtOAc/hexane 1:1) to give the two diastereoisomers of the title compound (total yield: 1.3 g): diastereoisomer A: 0.8 g; diastereoisomer B: 0.5 g. Diastereoisomer A: HRMS (FAB, M+H + ): m/e calc'd for C 32 H 29 N 2 O 3 Cl 2 F 6 ! + : 673.1459, found 673.1462; M.P. 80°-85° C. Diastereoisomer B: HRMS FAB, M+H + ): m/e calc'd for C 32 H 29 N 2 O 3 Cl 2 F 6 ! + : 673.1459, found 673.1455; M.P. 85°-88° C. ##STR376##
Treat a cold (5° C.), stirred solution of the product of Step 3 (2.02 g, 3 mmoles in 50 mL of dry THF) under N 2 with neat 10M (CH 3 ) 2 S·BH 3 (0.5 mL). Heat at reflux for 3 h, cool to room temperature and quench the reaction with 1N HCl (5 mL). Evaporate the solvent with warming under reduced pressure, treat the mixture with 50 mL of CH 3 OH and 2 g of K 2 CO 3 , stir with heating at reflux for 6 h. Cool the mixture, dilute with water (75 mL) and extract the product into CH 2 Cl 2 (2×50). Wash the organic layer with water (2×30 mL), dry (MgSO 4 ) and remove the solvent under vacuum. Purify the residue by silica gel flash chromatography (eluant: EtOAc/hexane/CH 3 OH, 4:5:1 to 6:3:1) to afford 0.330 g of diastereoisomer A and 0.180 g diastereoisomer B. Diastereoisomer A: HRMS (FAB, M+H + ): m/e calc'd for C 32 H 31 N 2 O 2 Cl 2 F 6 ! + : 659.1667, found 659.1665 Diastereoisomer B: HRMS (FAB, M+H + ): m/e calc'd for C 32 H 31 N 2 O 2 Cl 2 F 6 ! + : 659.1667, found 659.1665. ##STR377##
Wash Raney Nickel (0.3 g, 50% aqueous suspension) with EtOH (4×5 mL), add EtOH (15 mL), glacial HOAC (0.250 g) and the the product of Step 4 (diastereoisomer A, 0.3 g, 0.45 mmoles), degas and evacuate the mixture under vacuum. Introduce an atmosphere of H 2 gas and stir the mixture vigorously overnight at room temperature. Purge the mixture with N 2 , filter through celite and concentrate under vacuum. Pass the residue through a pad of silica gel, eluting with EtOAc, and concentrate to an oil to afford 0.206 g of the title compound as a mixture of diastereoisomers. HRMS (FAB, M+H + ): m/e calc'd for C 32 H 32 NO 3 Cl 2 F 6 ! + : 648.1496, found 648.1507.
Step 6: Treat a solution of the product of Step 5 (0.25 g, 0.37 mmoles) in CH 3 OH (2 mL) and pyridine (3 mL) with CH 3 ONH 2 HCl (0.50 gms, 0.71 mmoles) and heat at reflux for 3 h. Evaporate the solvent and dissolve the residue in EtOAc (5 mL), wash with water, dry (MgSO 4 ) and concentrate to afford 0.106 g of a mixture of diastereoisomers. HRMS (FAB, M+H + ): m/e calc'd for C 33 H 33 N 2 O 3 Cl 2 F 6 ! + : 691.1929, found 691.1938.
EXAMPLES 50 to 56
Using the procedures described below, compounds of the following formula were prepared, wherein the variables are as defined in the table:
______________________________________ ##STR378##Ex. A ##STR379## HRMS (FAB, M + H.sup.+): m/e calc'd HRMS (FAB, M + H.sup.+): m/e______________________________________ found50 NOCH.sub.3 CH.sub.2 C(O)CH.sub.2 689.1772 689.176551 NOCH.sub.3 CH.sub.2 C(NOH)CH.sub.2 704.1881 704.188952 NOCH.sub.3 CH.sub.2 C(NOCH.sub.3)CH.sub.2 718.2038 718.205153 NOH C(O)CH.sub.2 CH.sub.2 675.1616 675.159454 NOCH.sub.3 C(O)CH.sub.2 CH.sub.2 689.1772 689.177555 NH NHCH.sub.2 CH.sub.2 686.1827 686.184056 NOH NHCH.sub.2 688.1619 688.1626______________________________________
EXAMPLE 50
Treat a cold (-5° C.) acetone (10 mL) solution of the product of Example 49 (0.3 g, 0.433 mmoles) with 0.8 mL of freshly prepared Jones reagent (CrO 3 , H 2 SO 4 ). Stir for 15 min and neutralize to pH 8 with 2 mL of saturated aqueous NaHCO 3 diluted with 15 mL of water. Extract the product with CH 2 Cl 2 (2×10 mL), dry (MgSO 4 ) and remove the solvent by vacuum distillation to give a light brown solid (0.3 g). Purify the product by preparative silica gel TLC (CH 2 Cl 2 /CH 3 OH/NH 4 OH, 9:1:0.6) to give a yellow gummy solid (0.14 g).
EXAMPLE 51
Treat a mixture of the product of Example 50 (0.06 g, 0.087 mmoles), HONH 2 ·HCl (0.03 g, 0.43 mmoles) with pyridine (0.3 mL) in CH 3 OH (0.5 mL) and reflux with stirring under an inert atmosphere for 4 h. Cool the reaction mixture to room temperature, dilute with water (5 mL) and extract the product into EtOAc (2×5 mL). Wash the organic phase with water (2×5 mL), dry (MgSO 4 ) and concentrate under reduced pressure to an oil. Purify the product by preparative silica gel TLC (eluant: EtOAc/hexane, 2:1) to afford the title compound as a white solid (0.032 g). M.p.: 55°-60° C.
EXAMPLE 52
Treat a mixture of the product of Example 50 (0.04 g, 0.0578 mmoles) with CH 3 ONH 2 ·HCl (0.024 g, 0.29 mmoles) in a manner similar to that describd in Example 51 to afford the title compound as a yellow gum (0.02 g).
EXAMPLE 53 ##STR380##
Treat a 25 mL THF solution the product of Example 1, Step 2 (1.3 g, 2.97 mmoles) with 10M (CH 3 ) 2 S·BH 3 (0.9 mL, 9 mmoles) with stirring under N 2 . Heat the mixture to reflux for 2 h, cool to 5° C. and quench the reaction with 1.5M H 2 SO 4 . Dilute the mixture with 30 mL of water and extract the product into EtOAc (2×30 mL). Dry the organic layer (MgSO 4 ) and concentrate to dryness to afford a white solid. Take up the residue in CH 3 OH (40 mL) and add solid K 2 CO 3 (1 gm). Heat the mixture to reflux for 2 h, cool, filter through celite and concentrate to 1/3 the original volume. Dilute the mixture with water (25 mL), extract into EtOAc (2×30 mL), wash the organic layer with water (2×25 ml), dry and remove the solvent under vacuum to afford 1.06 g of the title compound. MS(Cl, M+H + ), m/e 423.
Step 2: Treat a suspension of potassium tert-butoxide in 5 mL of DMSO with a solution of the product of Step 1 (0.4 gm, 0.944 mmoles in 10 mL of DMSO). Stir at room temperature for 30 min, then treat with a solution of the product of Preparation 12 (1.369 g, 3.78 mmoles) in DMSO (10 mL). Stir the mixture at room temperature overnight under an inert atmosphere. Dilute the mixture with water (25 mL) and extract with EtOAc. Wash the organic phase with water (2×25 mL), dry and concentrate under reduced pressure to give a semisolid. Triturate the solid with Et 2 O and filter to give a light yellow solid (0.56 g). Recrystallize from CH 2 Cl 2 to give 0.36 g of a white solid. M.p. 145°-150°
Step 3: Treat the product of Step 2 (0.25 g, 0.36 mmoles) in 5 mL of CH 3 CN with Et 3 N (0.5 g, 0.5 mmoles) and CS 2 (0.4 g, 5 mmoles). Heat the reaction to 50° C. for 5 h. Remove solvent and excess volitiles by vacuum distillation and purify the product by preparative TLC (eluant, EtOAc/hexane/CH 3 OH, 5:4:1) to give the title compound (0.147 g).
EXAMPLE 54
Treat a solution of the product of Example 53 (0.05 g, 0.074 mmoles) in THF (1 mL) with a suspension of NaH (3.2 mg of a 60% dispersion in mineral oil, from which oil is removed by washing with 0.5 mL of hexane, 0.08 mmoles NaH) in THF (0.5 mL) at room temperature for 30 min with stirring under an inert atmosphere. Cool the mixture to -70° C. and treat with an 0.2M solution of CH 3 l in THF (0.4 mL, 0.08 mmoles). Gradually warm the mixture to 10° C. Add water (2 ml) and extract the product into EtOAc (5 mL), dry (MgSO 4 ) and concentrate under reduced pressure to give a yellow solid. Purify the product by preparative silica gel TLC (EtOAc/hexane, 2:1) to afford the title compound (0.012 g).
EXAMPLE 55
Step 1: Treat a solution (5 mL) of the product of Example 53, Step 1 (0.24 g, 0.56 mmoles) in CH 3 CN (5 mL) with Et 3 N (0.6 mL). Stir for 10 min at room temperature, add neat CS 2 , stir the mixture under N 2 overnight and then heat to 70° C. for 1 h. Remove solvent and excess volitles by vacuum distillation and the purify the product by preparative silica gel TLC (EtOAc/hexane, EtOAc/hexane 6:4, then CH 30 H/EtOAc/hexane 1:5:5) to afford 0.132 gm of the title compound. MS(Cl, M+H + ), m/e 389.
Step 2: Treat a solution of the product of Step 1 (0.201 g, 0.516 mmoles in 2 mL of CH 2 Cl 2 ) with a solution of Al(CH 3 ) 3 in hexane (0.26 mL of 2M Al(CH 3 ) 3 in hexane). In a separate flask, treat a solution of of the product of Preparation 13 (0.167 g, 0.568 mmoles in 2 mL of CH 2 Cl 2 ) with Al(CH 3 ) 3 (0.284 mL of 2M Al(CH 3 ) 3 ) and mix thoroughly. After 20 min, mix the two solutions and warm the resulting mixture to 70° C. overnight with stirring under N 2 . Dilute the reaction mixture with EtOAc (5mL) and treat with 0.2M HCl (5 mL) with thorough mixing. Wash the EtOAc layer with water, dry (MgSO 4 ) and concentrate to an oil. Purify the product by preparative silica gel TLC (eluant: EtOAc/Hexane/CH 3 OH, 5:4:1) to afford 0.0135 g of the title compound.
EXAMPLE 56
Step 1: Treat the product of Example 55, Step 1 (0.33 g, 0.85 mmoles) in 6 mL of a mixture of CH 3 OH and pyridine (5:1) with HONH 2 HCl (0.08g, 1.1 mmoles) and heat for 1 h at reflux with stirring under N 2 . Cool the mixture to room temperature and remove the solvent by vacuum distillation. Purify the residue by preparative silica gel TLC (eluant: EtOAc/hexane, 2:1) to obtain a white solid (0.350 gm). HRMS (FAB, M+H + ): m/e calc'd for C 21 H 26 N 3 O 2 Cl 2 ! + : 422.1402, found 422.1404.
Step 2: Treat the product of Step 1 (0.1 g, 0.24 mmoles) in dry pyridine (1.5 mL) at 0° C. with 3,5-bis(trifluoromethyl)benzoyl chloride (0.07 gm, 0.25 mmoles) with stirring under N 2 . Warm the reaction to room temperature over 1/2 h, then heat at 80° C. for 1 h. Remove the solvent by vacuum distillation and purify the product by preparative silica gel TLC (EtOAc/hexane 1:1) to afford a clear glassy solid (0.127 g). MS(Cl, M+H 30 ), m/e 611.
Step 3: Treat a solution of the product of Step 3 (0.1 g, 0.155 mmoles in 3 mL of Et 2 O) with three portions (50 mgs each) solid LiAlH 4 . Stir the mixture under N 2 for 1 h at room temperature and then carefully quench with a mixture of CH 3 OH and 3M NaOH (1:1, 2 mL). Remove solids by filtration through celite and remove solvent by vacuum distillation to afford a gummy residue. Purify the product by preparative silica gel TLC (eluant, EtOAc/hexane/CH 3 OH, 8:1:1) to afford the title compound as a glassy solid (0.27 g).
The following formulations exemplify some of the dosage forms of this invention. In each, the term "active compound" refers to a ound of formula I.
EXAMPLE A
______________________________________TabletsNo. Ingredient mg/tablet mg/tablet______________________________________1 Active Compound 100 5002 Lactose USP 122 1133 Corn Starch, Food Grade, as a 10% 30 40paste in Purified Water4 Corn Starch, Food Grade 45 405 Magnesium Stearate 3 7Total 300 700______________________________________
Method of Manufacture
Mix Item Nos. 1 and 2 in suitable mixer for 10-15 minutes. Granulate the mixture with Item No. 3. Mill the damp granules through a coarse screen (e.g., 1/4", 0.63 cm) if necessary. Dry the damp granules. Screen the dried granules if necessary and mix with Item No. 4 and mix for 10-15 minutes. Add Item No. 5 and mix for 1-3 minutes. Compress the mixture to appropriate size and weight on a suitable tablet machine.
EXAMPLES B
______________________________________CapsulesNo. Ingredient mg/tablet mg/tablet______________________________________1 Active Compound 100 5002 Lactose USP 106 1233 Corn Starch, Food Grade 40 704 Magnesium Stearate NF 4 7 Total 250 700______________________________________
Method of Manufacture
Mix Item Nos. 1, 2 and 3 in a suitable blender for 10-15 minutes. Add Item No. 4 and mix for 1-3 minutes. Fill the mixture into suitable two-piece hard gelatin capsules on a suitable encapsulating machine.
EXAMPLE C
______________________________________Sterile Powder for InjectionIngredient mg/vial mg/vial______________________________________Active sterile powder 100 500______________________________________
For reconstitution add sterile water for injection or bacteriostatic water for injection.
The in vitro and in vivo activity of the compounds of formula I can be determined by the following procedures.
In Vitro Procedure to Identify NK 1 Activity
Test compounds are evaluated for their ability to inhibit the activity of the NK 1 agonist Substance P on the isolated guinea pig vas deferens. Freshly cut vas deferens are removed from male Hartley guinea pigs (230-350 g) and suspended in 25 ml tissue baths containing Kreb's Henseleit solution warmed to 37° C. and constantly aerated with 95% O 2 and 5% CO 2 . Tissues are adjusted to 0.5 g and allowed to equilibrate for a period of 30 minutes. The vas deferens are exposed to an electrical field stimulation (Grass S48 Stimulator) every 60 seconds at an intensity that will cause the tissue to contract 80% of its maximum capacity. All responses are recorded isometrically by means of a Grass force displacement transducer (FT03) and Harvard electronic recorder. Substance P inhibits the electrical field stimulated-induced contractions of the guinea pig vas deferens. In unpaired studies, all tissues (control or drug treated) are exposed to cumulative concentations of Substance P (1×10 -10 M-7×10 -7 M). Single log-concentations of the test compounds are given to separate tissues and allowed to equilibrate for 30 minutes before a Substance P concentation-response curve is generated. At least 5 separate tissues are used for each control and individual drug-concentation for every drug assay.
Inhibition of the Substance P is demonstrated by a rightward shift of its concentration-response curve. These shifts are used to determine the pA 2 value, which is defined as the negative log of the molar concentration of the inhibitor which would require that twice as much agonist be used to elicit a chosen response. This value is used to determine relative antagonist potency.
Isolated Hamster Trachea NK 2 Assay
General methodology and characterization of hamster trachea responses to neurokinin agonists as providing an NK 2 monoreceptor assay is found in C. A. Maggi, et al., Eur. J. Pharmacol 166 (1989) 435 and J. L. Ellis, et al., J. Pharm. Exp. Ther. 267 (1993) 95.
Continuous isometric tension monitoring is achieved with Grass FT-03 force displacement transducers connected to Buxco Electronics preamplifiers built into a Graphtec Linearcorder Model WR 3310.
Male Charles River LAK:LVG (SYR) hamsters, 100-200 g fed weight, are stunned by a sharp blow to the head, loss of corneal reflex is assured, the hamsters are sacrificed by thoractomy and cutting the heart. Cervical trachea segments are removed to room temperature Krebs buffer, pH 7.4, aerated with 95% O 2 -5% CO 2 gas and cleaned of adhering tissue. The segments are cut into two 3-4 mm long ring segments. Tracheal rings are suspended from transducers and anchored in 15.0 ml water jacketed organ baths by means of stainless steel hooks and 6-0 silk. Baths are filled with Krebs buffer, pH 7.4, maintained at 37° C. and continuously aerated with 95% O2-5% CO 2 gas. Tracheal rings are placed under 1.0 g initial tension and allowed a 90 min equilibration period with four 1 μM NKA challenge, wash and recovery cycles at 20 min intervals. 30 min vehicle pretreatment is followed by cumulative additions of rising doses of NKA (3 nM-1 μM final concentration, 5 min intervals between additions). The final NKA response is followed by a 15 min wash and recovery period. 30 min pretreatment with a test compound or its vehicle is followed by cumulative additions of rising doses of NKA (3 nM-10μM final concentration if necessary, 5 min intervals between additions). The final NKA response is followed by a 1 mM carbachol challenge to obtain a maximal tension response in each tissue.
Tissue responses to NKA are recorded as positive pen displacements over baseline and converted to grams tension by comparison to standard weights. Responses are normalized as a % of the maximal tissue tension. ED 50 's are calculated for NKA from the control and treated NKA dose responses and compared. Test compounds resulting in an agonist dose ratio ≧2 at a screening concentration of 1 μM (i.e. pA 2 ≧ =6.0) are considered actives. Further dose response data is obtained for actives so that an apparent pA 2 estimate can be calculated. pA 2 is calculated either by estimation of K i as described by Furchgott (where pA 2 =-Log K i , R. F. Furchgott, Pharm. Rev. 7 1995! 183) or by Shild Plot Analysis (O. Arunlakshana & H. O. Shild, Br. J. Pharmacol. 14 1959! 48) if the data is sufficient.
Effect of NK 1 Antagonists on Substance P-Induced Airway Microvascular Leakage in Guinea Pigs
Studies are performed on male Hartley guinea pigs ranging in weight from 400-650 g. The animals are given food and water ad libitum. The animals are anesthetized by intraperitoneal injection of dialurethane (containing 0.1 g/ml diallylbarbituric acid, 0.4 g/ml ethylurea and 0.4 g/ml urethane). The trachea is cannulated just below the larynx and the animals are ventilated (V T =4 ml, f=45 breaths/min) with a Harvard rodent respirator. The jugular vein is cannulated forthe injection of drugs.
The Evans blue dye technique (Danko, G. et al., Pharmacol. Commun., 1, 203-209, 1992) is used to measure airway microvascular leakage (AML). Evans blue (30 mg/kg) is injected intravenously, followed 1 min later by i.v. injection of substance P (10 μg/kg). Five min later, the thorax is opended and a blunt-ended 13-guage needle passed into the aorta. An incision is made in the right atrium and blood is expelled by flushing 100 ml of saline through the aortic catheter. The lungs and trachea are removed en-bloc and the trachea and bronchi are then blotted dry with filter paper and weighed. Evans blue is extracted by incubation of the tissue at 37° C. for 18 hr in 2 ml of formamide in stoppered tubes. The absorbance of the formamide extracts of dye is measured at 620 nm. The amount of dye is calculated by interpolation from a standard curve of Evans blue in the range 0.5-10 μg/ml in formamide. The dye concentration is expressed as ng dye per mg tissue wet weight. Test compounds were suspended in cyclodextran vehicle and given i.v. 5 min before substance P.
Measurement of NK 2 Activity In Vivo
Male Hartley guinea pigs (400-500 gm) with ad lib. access to food and water are anesthetized with an intraperitoneal injection of 0.9 ml/kg dialurethane (containing 0.1 g/m diallylbarbituric acid, 0.4 g/ml ethylurea and 0.4 g/ml urethane). After induction of a surgical plane of anesthesia, tracheal, esophageal and jugular venous cannulae are implanted to facilitate mechanical respiration, measurement of esophageal pressure and administration of drugs, respectively.
The guinea pigs are placed inside a whole body plethysmograph and the catheters connected to outlet ports in the plethysmograph wall. Airflow is measured using a differential pressure transducer (Validyne, Northridge CA, model MP45-1, range ±2 cmH 2 O) which measures the pressure across a wire mesh screen that covers a 1 inch hole in the wall of the plethysmograph. The airflow signal is electrically integrated to a signal proportional to volume. Transpulmonary pressure is measured as the pressure difference between the trachea and the esophagus using a differential pressure transducer (Validyne, Northridge, CA, model MP45-1, range ±20 cm H 2 O). The volume, airflow and transpulmonary pressure signals are monitored by means of a pulmonary analysis computer (Buxco Electronics, Sharon, CT, model 6) and used for the derivation of pulmonary resistance (R L ) and dynamic lung compliance (C Dyn ).
Bronchoconstriction Due to NKA
Increasing iv doses of NKA are administered at half log (0.01-3 μg/kg) intervals allowing recovery to baseline pulmonary mechanics between each dose. Peak bronchoconstriction occurs within 30 seconds after each dose of agonist. The dose response is stopped when C Dyn is reduced 80-90% from baseline. One dose-response to NKA is performed in each animal. Test compounds are suspended in cyclodextran vehicle and given i.v. 5 min before the initiation of the NKA dose response.
For each animal, dose response curves to NKA are constructed by plotting the percent increase in R L or decrease in C Dyn against log dose of agonist. The doses of NKA that increased R L by 100% (R L 100) or decreased C Dyn by 40% (C Dyn 40) from baseline values are obtained by log-linear interpolation of the dose response curves.
Neurokinin Receptor Binding Assay(s)
Chinese Hamster ovary (CHO) cells transfected with the coding regions for the human neurokinin 1 (NK1) of the human neurokinin 2 (NK2) receptors are grown in Dulbecco's minimal essential medium supplemented with 10% fetal calf serum, 0.1 mM non-essential amino acids, 2 mM glutamine, 100units/ml of penicillin and streptomycin, and 0.8 mg of G418/ml at 37° C. in a humidified atmosphere containing 5% CO 2 .
Cells are detached from T-175 flasks with a sterile solution containing 5 mM EDTA in phosphate buffered saline. Cells are harvested by centrifugation and washed in RPMl media at 40° C. for 5 minutes. The pellet is resuspended inTris-HCl (pH7.4) containing 1 uM phsphoramidon and 4 ug/ml of chymostatin at a cell density of 30×10 6 cells/ml. The suspension is then homogenized in a Brinkman Polytron (setting 5) for 30-45 seconds. The homogenate is centrifuged at 800×g for 5 min at 4° C. to collect unbroken cells and nuclei. The supernatant is centrifuged in a Sorvall RC5C at 19,000 rpm (44,00×g) for 30 min at 4° C. The pellet is resuspended, an aliquot is removed for a protein determination (BCA) and washed again. The resulting pellet is stored at -80° C.
To assay receptor binding, 50 μl of 3 H!-Substance P (9-Sar, 11 -Met 02!) (specific activity 41 Ci/mmol) (Dupont-NEN) (0.8 nM for the NK-1 assay) or 3 H!-Neurokinin A (specific activity 114 Ci/mmole) (Zenca) (1.0 nM for the NK-2 assay) is added to tubes containing buffer (50 mM Tris-HCl (pH 7.4) with 1 mM MnCl 2 and 0.2% Bovine Serum Albumin) and either DMSO or test compound. Binding is initiated by the addition of 100 μl of membrane (10-20 μg) containing the human NK-1 or NK-2 receptor in a final volume of 200 μl. After 40 minutes at room temperature, the reaction is stopped by rapid filtration onto Whatman GF/C filters which have been presoaked in 0.3% polyethylenimine. Filters are washed 2 times with 3 ml of 50 mM Tris-HCl (pH7.4). Filters are added to 6 mIs of Ready-Safe liquid scintillation cocktail and quantified by liquid scintillation spectrometry in a LKB 1219 RackBeta counter. Non-specific binding is determined by the addition of either 1 μM of CP-99994 (NK-1) or 1 μM SR-48968 (NK-2) (both synthesized by the chemistry department of Schering-Plough Research Institute). IC 50 values are determined from competition binding curves and Ki values are determined according to Cheng and Prusoff using the experimentally determined value of 0.8 nM for the NK-1 receptor and 2.4 nM for the NK-2 receptor.
NK 3 activity is determined by following a procedure similar to that described in the literature, e.g., Molecular PharmacoL, 48 (1995), p. 711-716.
% Inhibition is the difference between the percent of maximum specific binding (MSB) and 100%. The percent of MSB is defined by the following equation, wherein "dpm" is disintegrations per minute: ##EQU1##
It will be recognized that compounds of formula I exhibit NK 1 , NK 2 and/or NK 3 antagonist activity to varying degrees, e.g., certain compounds have strong NK 1 antagonist activity, but weaker NK 2 and NK 3 antagonist activity, while others are strong NK 2 antagonists, but weaker NK 1 and NK 3 antagonists. While compounds with approximate equipotency are preferred, it is also within the scope of this invention to use compounds of with unequal NK 1 /NK 2 /NK 3 antagonist activity when clinically appropriate.
Using the test procedures described above, the following data (% inhibition or Ki) were obtained for preferred and/or representative of formula I:
______________________________________ % Inhibition % Inhibition NK.sub.1 Ki (NK.sub.1) NK.sub.2 Ki (NK.sub.2) Ki (NK.sub.3)Ex. (1 μM dose) (nM) (1 μM dose) (nM) (nM)______________________________________1 88.0 25 95.0 20 1091C 44.0 -- 16.0 -- --2 69.0 40 17.0 -- --7 69.0 121 13.0 -- --22AK 67 132 95 2.0 --22AL 12.0 -- 100 2.0 --35C 93 2.0 0.0 -- --39F 93 4.3 96 12.0 --42L 91 4.6 86 123.0 --______________________________________
Compounds of the present invention exhibit a range of activity: percent inhibition at a dosage of 1 μM ranges from about 0 to about 100% inhibition of NK 1 and/or about 0to about 100% inhibition of NK 2 . Preferred are compounds having a Ki≦100 nM for the NK 1 receptor. Also preferred are compounds having a Ki≦100 nM for the NK 2 receptor. Another group of preferred compounds are those having a Ki≦100 nM for each of the NK 1 and NK 2 receptors. | Compound represented by the structural formula ##STR1## or a pharmaceutically acceptable salt thereof, wherein: a is 0, 1, 2 or3;
b, d and e are independently 0, 1 or 2;
R is H, C 1-6 alkyl, --OH or C 2 -C 6 hydroxyalkyl;
A is an optionally substituted oxime, hydrazone or olefin;
X is a bond, --C(O)--, --O--, --NR 6 --, --S(O)e--, --N(R 6 )C(O)--, --C(O)N(R 6 )-- --OC(O)NR 6 --, --OC(═S)NR 6 --, --N(R 6 )C(═S)O--, --C(═NOR 1 )--, --S(O) 2 N(R 6 )--, --N(R 6 )S(O) 2 --, --N(R 6 )C(O)O-- or --OC(O)--;
T is H, phthalimidyl, aryl, heterocycloalkyl, heteroaryl, cycloalkyl or bridged cycloalkyl;
Q is --SR 6 , --N(R 6 )(R 7 ), --OR 6 , phenyl, naphthyl or heteroaryl;
R 6a , R 7a , R 8a , R 9a , R 6 and R 7 are H, C 1-6 alkyl, C 2 -C 6 hydroxyalkyl, C 1 -C 6 alkoxy-C 1 -C 6 alkyl, phenyl or benzyl; or R 6 and R 7 , together with the nitrogen to which they are attached, form a ring;
R 9a is R 6 or --OR 6 ;
Z is morpholinyl, optionally N-substituted piperazinyl, optionally substituted ##STR2## or substituted ##STR3## g is 0-3 and h is 1-4, provided the sum of h and g is 1-7; wherein aryl, heterocycloalkyl, heteroaryl, cycloalkyl and bridged cycloalkyl groups are optionally substituted; methods of treating asthma, cough, bronchospasm, imflammatory diseases, and gastrointestinal disorders with said compounds, and pharmaceutical compositions comprising said compounds are disclosed. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a division of U.S. application Ser. No. 09/515,383, filed Feb. 29, 2000, entitled Retinal Color Prosthesis for Color Sight Restoration, now U.S. Pat. No. 6,507,758, which claims priority of U.S. Provisional Application 60/125,873, filed Mar. 24, 1999, entitled Method and Apparatus for Sight Restoration.
TECHNICAL FIELD OF INVENTION
The present invention relates to electrical stimulation of the retina to produce artificial images for the brain. It relates to electronic image stabilization techniques based on tracking the movements of the eye. It relates to telemetry in and out of the eye for uses such as remote diagnostics and recording from the retinal surface.
The present invention also relates to electrical stimulation of the retina to produce phosphenes and to produce induced color vision. The present invention relates to hermetically sealed electronic and electrode units which are safe to implant in the eye.
BACKGROUND
Color perception is part of the fabric of human experience. Homer (c. 1100 b.c.) writes of “the rosy-fingered dawn”. Lady Murasaki no Shikibu (c. 1000 a.d.) uses word colors (“purple, yellow shimmer of dresses, blue paper”) in the world's first novel. In the early nineteenth century Thomas Young, an English physician, proposed a trichromatic theory of color vision, based on the action of three different retinal receptors. Fifty years later James Clerk Maxwell, the British physicist and Hermann von Hehnholtz, the German physiologist, independently showed that all of the colors we see could be made up from three suitable spectral color lights. In 1964 Edward MacNichol and colleagues at Johns Hopkins and George Wald at Harvard measured the absorption by the visual pigments in cones, which are the color receptor cells. Rods are another type of photoreceptor cell in the primate retina. These cells are more sensitive to dimmer light but are not directly involved in color perception. The individual cones have one of three types of visual pigment. The first is most sensitive to short waves, like blue. The second pigment is most sensitive to middle wavelengths, like green. The third pigment is most sensitive to longer wavelengths, like red.
The retina can be thought of a big flower on a stalk where the top of that stalk is bent over so that the back of the flower faces the sun. In place of the sun, think of the external light focused by the lens of the eye onto the back of the flower. The cones and rods cells are on the front of the flower; they get the light that has passed through from the back of the somewhat transparent flower. The photoreceptor nerve cells are connected by synapses to bipolar nerve cells, which are then connected to the ganglion nerve cells. The ganglion nerve cells connect to the optic nerve fibers, which is the “stalk” that carries the information generated in the retina to the brain. Another type of retinal nerve cell, the horizontal cell, facilitates the transfer of information horizontally across bipolar cells. Similarly, another type of cell, the amacrine facilitates the horizontal transfer of information across the ganglion cells. The interactions among the retinal cells can be quite complex. On-center and off-center bipolar cells can be stimulated at the same time by the same cone transmitter release to depolarize and hyperpolarize, respectively. A particular cell's receptive field is that part of the retina, which when stimulated, will result in that cell's stimulation. Thus, most ganglion cells would have a larger receptive field than most bipolar cells. Where the response to the direct light on the center of a ganglion cells receptive field is antagonized by direct light on the surround of its receptive field, the effect is called center-surround antagonism. This phenomenon is important for detecting borders independent of the level of illumination. The existence of this mechanism for sharpening contrast was first suggested by the physicist Ernst Mach in the late 1800's. More detailed theories of color vision incorporate color opponent cells. On the cone level, trichromatic activity of the cone cells occurs. At the bipolar cell level, green-red opponent and blue-yellow opponent processing systems of the center-surround type, occur. For example, a cell with a green responding center would have an annular surround area, which responded in an inhibiting way to red. Similarly there can be red-center responding, green-surround inhibiting response. The other combinations involve blue and yellow in an analogous manner.
It is widely known that Galvani, around 1780, stimulated nerve and muscle response electrically by applying a voltage on a dead frog's nerve. Less well known is that in 1755 LeRoy discharged a Leyden jar, i.e., a capacitor, through the eye of a man who had been blinded by the growth of a cataract. The patient saw “flames passing rapidly downward.”
In 1958, Tassicker was issued a patent for a retinal prosthetic utilizing photosensitive material to be implanted subretinally. In the case of damage to retinal photoreceptor cells that affected vision, the idea was to electrically stimulate undamaged retinal cells. The photosensitive material would convert the incoming light into an electrical current, which would stimulate nearby undamaged cells. This would result in some kind of replacement of the vision lost. Tassicker reports an actual trial of his device in a human eye. (U.S. Pat. No. 2,760,483).
Subsequently, Michelson (U.S. Pat. No. 4,628,933), Chow (U.S. Pat. Nos. 5,016,633; 5,397,350; 5,556,423), and De Juan (U.S. Pat. No. 5,109,844) all were issued patents relating to a device for stimulating undamaged retinal cells. Chow and Michelson made use of photodiodes and electrodes. The photodiode was excited by incoming photons and produced a current at the electrode.
Normann et al. (U.S. Pat. No. 5,215,088) discloses long electrodes 1000 to 1500 microns long designed to be implanted into the brain cortex. These spire-shaped electrodes were formed of a semiconductor material.
Najafi, et al., (U.S. Pat. No. 5,314,458), disclosed an implantable silicon-substrate based microstimulator with an external device which could send power and signal to the implanted unit by RF means. The incoming RF signal could be decoded and the incoming RF power could be rectified and used to run the electronics.
Difficulties can arise if the photoreceptors, the electronics, and the electrodes all tend to be mounted at one place. One issue is the availability of sufficient area to accommodate all of the devices, and another issue is the amount of power dissipation near the sensitive retinal cells. Since these devices are designed to be implanted into the eye, this potential overheating effect is a serious consideration.
Since these devices are implants in the eye, a serious problem is how to hermetically seal these implanted units. Of further concern is the optimal shape for the electrodes and for the insulators, which surround them. In one embodiment there is a definite need that the retinal device and its electrodes conform to the shape of the retinal curvature and at the same time do not damage the retinal cells or membranes.
The length and structure of electrodes must be suitable for application to the retina, which averages about 200 microns in thickness. Based on this average retinal thickness of 200 microns, elongated electrodes in the range of 100 to 500 microns appear to be suitable. These elongated electrodes reach toward the cells to be activated. Being closer to the targeted cell, they require less current to activate it.
In order not to damage the eye tissue there is a need to maintain an average charge neutrality and to avoid introducing toxic or damaging effects from the prosthesis.
A desirable property of a retinal prosthetic system is making it possible for a physician to make adjustments on an on-going basis from outside the eye. One way of doing this would have a physician's control unit, which would enable the physician to make adjustments and monitor the eye condition. An additional advantageous feature would enable the physician to perform these functions at a remote location, e.g., from his office. This would allow one physician to remotely monitor a number of patients remotely without the necessity of the patient coming to the office. A patient could be traveling distantly and obtain physician monitoring and control of the retinal color prosthetic parameters.
Another version of the physician's control unit is a hand-held, palm-size unit. This unit will have some, but not all of the functionality of the physician's control unit. It is for the physician to carry on his rounds at the hospital, for example, to check on post-operative retinal-prosthesis implant patients. Its extreme portability makes other situational uses possible, too, as a practical matter.
The patient will want to control certain aspects of the visual image from the retinal prosthesis system, in particular, image brightness. Consequently, a patient controller, performing fewer functions than the physician's controller is included as part of the retinal prosthetic system. It will control, at a minimum, bright image, and it will control this image brightness in a continuous fashion. The image brightness may be increased or decreased by the patient at any time, under normal circumstances.
A system of these components would itself constitute part of a visual prosthetic to form images in real time within the eye of a person with a damaged retina. In the process of giving back sight to those who are unable to see, it would be advantageous to supply artificial colors in this process of reconstructing sight so that the patient would be able to enjoy a much fuller version of the visual world.
In dealing with externally mounted or externally placed means for capturing image and transmitting it by electronic means or other into the eye, one must deal with the problem of stabilization of the image. For example, a head-mounted camera would not follow the eye movement. It is desirable to track the eye movements relative to the head and use this as a method or approach to solving the image stabilization problem.
By having a method and apparatus for the physician and the technician to initially set up and measure the internal activities and adjust these, the patient's needs can be better accommodated. The opportunity exists to measure internal activity and to allow the physician, using his judgment, to adjust settings and controls on the electrodes. Even the individual electrodes would be adjusted by way of the electronics controlling them. By having this done remotely, by remote means either by telephone or by the Internet or other such, it is clear that a physician would have the capability to intervene and make adjustment as necessary in a convenient and inexpensive fashion, to serve many patients.
SUMMARY OF INVENTION
The objective of the current invention is to restore color vision, in whole or in part, by electrically stimulating undamaged retinal cells, which remain in patients with lost or degraded visual function arising, for example, from Retinitis Pigmentosa or Age-Related Macular Degeneration. This invention is directed toward patients who have been blinded by degeneration of photoreceptors; but who have sufficient bipolar cells, or other cells acting similarly, to permit electrical stimulation.
There are three main functional parts to this invention. One is external to the eye. The second part is internal to the eye. The third part is the communication circuitry for communicating between those two parts. Structurally there are two parts. One part is external to the eye and the other part is implanted internal to the eye. Each of these structural parts contains two way communication circuitry for communication between the internal and external parts.
The structural external part is composed of a number of subsystems. These subsystems include an external imager, an eye-motion compensation system, a head motion compensation system, a video data processing unit, a patient's controller, a physician's local controller, a physician's remote controller, and a telemetry unit. The imager is a video camera such as a CCD or CMOS video camera. It gathers an image approximating what the eyes would be seeing if they were functional.
The imager sends an image in the form of electrical signals to the video data processing unit. In one aspect, this unit formats a grid-like or pixel-like pattern that is then ultimately sent to electronic circuitry (part of the internal part) within the eye, which drives the electrodes. These electrodes are inside the eye. They replicate the incoming pattern in a useable form for stimulation of the retina so as to reproduce a facsimile of the external scene. In an other aspect of this invention other formats other than a grid-like or pixel like pattern are used, for example a line by line scan in some order, or a random but known order, point-by-point scan. Almost any one-to-one mapping between the acquired image and the electrode array is suitable, as long as the brain interprets the image correctly.
The imager acquires color information. The color data is processed in the video data processing unit. The video data processing unit consists of microprocessor CPU's and associated processing chips including high-speed data signal processing (DSP) chips.
In one aspect, the color information is encoded by time sequences of pulses separated by varying amounts of time; and, the pulse duration may be different for various pulses. The basis for the color encoding is the individual color code reference ( FIG. 2 a ). The electrodes stimulate the target cells so as to create a color image for the patient, corresponding to the original image as seen by the video camera, or other imaging means.
Color information, in an alternative aspect, is sent from the video data processing unit to the electrode array, where each electrode has been determined to stimulate preferentially one of the bipolar cell types, namely, red-center green-surround, green-center-red-surround, blue-center-yellow-surround, or yellow-center-blue-surround.
An eye-motion compensation system is an aspect of this invention. The eye tracker is based on detection of eye motion from the corneal reflex or from implanted coils of wire, or, more generally, insulated conductive coils, on the eye or from the measurement of electrical activity of extra-ocular muscles. Communication is provided between the eye tracker and the video data processing unit by electromagnetic or acoustical telemetry. In one embodiment of the invention, electromagnetic-based telemetry may be used. The results of detecting the eye movement are transmitted to a video data processing unit, together with the information from the camera means. Another aspect of the invention utilizes a head motion sensor and head motion compensation system. The video data processing unit can incorporate the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion.
The internal structural part, which is implanted internally within the eye, is also composed of a number of subsystems. These can be categorized as electronic circuits and electrode arrays, and communication subsystems, which may include electronic circuits. The circuits, the communication subsystems, and the arrays can be hermetically sealed and they can be attached one to the other by insulated wires. The electrode arrays and the electronic circuits can be on one substrate, or they may be on separate substrates joined by an insulated wire or by a plurality of insulated wires. This is similarly the case for a communication subsystem.
A plurality of predominately electronic substrate units and a plurality of predominately electrode units may be implanted or located within the eye as desired or as necessary. The electrodes are designed so that they and the electrode insulation conform to the retinal curvature. The variety of electrode arrays include recessed electrodes so that the electrode array surface coming in contact with the retinal membrane or with the retinal cells is the non-metallic, more inert insulator.
Another aspect of the invention is the elongated electrode, which is designed to stimulate deeper retinal cells by penetrating into the retina by virtue of the length of its electrodes. A plurality of electrodes is used. The elongated electrodes are of lengths from 100 microns to 500 microns. With these lengths, the electrode tips can reach through those retinal cells not of interest but closer to the target stimulation cells, the bipolar cells. The number of electrodes may range from 100 on up to 10,000 or more. With the development of electrode fabrication technology, the number of electrodes might rage up to one million or more.
Another aspect of the invention uses a plurality of capacitive electrodes to stimulate the retina, in place of non-capacitive electrodes. Another aspect of the invention is the use of a neurotrophic factor, for example, Nerve Growth Factor, applied to the electrodes, or to the vicinity of the electrodes, to aid in attracting target nerves and other nerves to grow toward the electrodes.
Hermetic sealing is accomplished by coating the object to be sealed with a substance selected from the group consisting of silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide, zirconium oxide. This hermetic sealing aspect of the invention provides an advantageous alternative to glass coverings for hermetic seals, being less likely to become damaged.
Another feature of one aspect of the structural internal-to-the-eye subsystems is that the electronics receive and transmit information in coded or pulse form via electromagnetic waves. In the case where electromagnetic waves are used, the internal-to-the-eye-implanted electronics can rectify the RF, or electromagnetic wave, current and decode it. The power being sent in through the receiving coil is extracted and used to drive the electronics. In some instances, the implanted electronics acquire data from the electrode units to transmit out to the video data processing unit.
In another aspect the information coding is done with ultrasonic sound. An ultrasonic transducer replaces the electromagnetic wave receiving coil inside the eye. An ultrasonic transducer replaces the coil outside the eye for the ultrasonic case. By piezoelectric effects, the sound vibration is turned into electrical current, and energy extracted therefrom.
In another aspect of the invention, information is encoded by modulating light. For the light modulation case, a light emitting diode (LED) or laser diode or other light generator, capable of being modulated, acts as the information transmitter. Information is transferred serially by modulating the light beam, and energy is extracted from the light signal after it is converted to electricity. A photo-detector, such as a photodiode, which turns the modulated light signal into a modulated electrical signal, is used as a receiver.
Another aspect of the structural internal-to-the-eye subsystems of this invention is that the predominately electrode array substrate unit and the predominately electronic substrate unit, which are joined by insulated wires, can be placed near each other or in different positions. For example, the electrode array substrate unit can be placed subretinally and the electronic substrate unit placed epiretinally. On a further aspect of this invention, the electronic substrate unit can be placed distant from the retina so as to avoid generating additional heat or decreasing the amount of heat generated near the retinal nerve system. For example, the receiving and processing circuitry could be placed in the vicinity of the pars plana. In the case where the electronics and the electrodes are on the same substrate chip, two of these chips can be placed with the retina between them, one chip subretinal and the other chip epiretinal, such that the electrodes on each may be aligned. Two or more guide pins with corresponding guide hole or holes on the mating chip accomplish the alignment. Alternatively, two or more tiny magnets on each chip, each magnet of the correct corresponding polarity, may similarly align the sub- and epiretinal electrode bearing chips. Alternatively, corresponding parts which mate together on the two different chips and which in a fully mated position hold each other in a locked or “snap-together” relative position.
Now as an element of the external-to-the-eye structural part of the invention, there is a provision for a physician's hand-held test unit and a physician's local or remote office unit or both for control of parameters such as amplitudes, pulse widths, frequencies, and patterns of electrical stimulation.
The physician's hand-held test unit can be used to set up or evaluate and test the implant during or soon after implantation at the patient's bedside. It has, essentially, the capability of receiving what signals come out of the eye and having the ability to send information in to the retinal implant electronic chip. For example, it can adjust the amplitudes on each electrode, one at a time, or in groups. The hand-held unit is primarily used to initially set up and make a determination of the success of the retinal prosthesis.
The physician's local office unit, which may act as a set-up unit as well as a test unit, acts directly through the video data processing unit. The remote physician's office unit would act over the telephone lines directly or through the Internet or a local or wide area network. The office units, local and remote, are essentially the same, with the exception that the physician's remote office unit has the additional communications capability to operate from a location remote from the patient. It may evaluate data being sent out by the internal unit of the eye, and it may send in information. Adjustments to the retinal color prosthesis may be done remotely so that a physician could handle a multiple number of units without leaving his office. Consequently this approach minimizes the costs of initial and subsequent adjustments.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features and advantages of the invention will be more apparent from the following detailed description wherein:
FIG. 1 a shows the general structural aspects of the retina color prosthesis system;
FIG. 1 b shows the retina color prosthesis system with a structural part internal (to the eye), with an external part with subsystems for eye-motion feedback to enable maintaining a stable image presentation, and with a subsystems for communicating between the internal and external parts, and other structural subsystems;
FIG. 1 c shows an embodiment of the retina color prosthesis system which is, in part, worn in eyeglass fashion;
FIG. 1 d shows the system in FIG. 1 c in side view;
FIG. 2 a shows an embodiment of the color I coding schemata for the stimulation of the sensation of color;
FIG. 2 b represents an embodiment of the color I conveying method where a “large” electrode stimulates many bipolar cells with the color coding schemata of FIG. 2 a;
FIG. 2 c represents an embodiment of the color II conveying, method where an individual electrode stimulates a single type of bipolar cell;
FIG. 3 a represents an embodiment of the telemetry unit including an external coil, an internal (to the eye) coil, and an internal electronic chip;
FIG. 3 b represents an embodiment of the telemetry unit including an external coil, an internal (to the eye) coil, an external electronic chip, a dual coil transfer unit, and an internal electrode array;
FIG. 3 c shows and acoustic energy and information transfer system;
FIG. 3 d shows a light energy and information transfer system;
FIG. 4 represents an embodiment of the external telemetry unit;
FIG. 5 shows an embodiment of an internal telemetry circuit and electrode array switcher;
FIG. 6 a shows a monopolar electrode arrangement and illustrates a set of round electrodes on a substrate material;
FIG. 6 b shows a bipolar electrode arrangement;
FIG. 6 c shows a multipolar electrode arrangement;
FIG. 7 shows the corresponding indifferent electrode for monopolar electrodes;
FIG. 8 a depicts the location of an epiretinal electrode array located inside the eye in the vitreous humor located above the retina, toward the lens capsule and the aqueous humor;
FIG. 8 b shows recessed epiretinal electrodes where the electrically conducting electrodes are contained within the electrical insulation material; a silicon chip acts as a substrate; and the electrode insulator device is shaped so as to contact the retina in a conformal manner;
FIG. 8 c is a rendering of an elongated epiretinal electrode array with the electrodes shown as pointed electrical conductors, embedded in an electrical insulator, where an pointed electrodes contact the retina in a conformal manner, however, elongated into the retina;
FIG. 9 a shows the location of a subretinal electrode array below the retina, away from the lens capsule and the aqueous humor. The retina separates the subretinal electrode array from the vitreous humor;
FIG. 9 b illustrates the subretinal electrode array with pointed elongated electrode, the insulator, and the silicon chip substrate where the subretinal electrode array is in conformal contact with the retina with the electrodes elongated to some depth;
FIG. 10 a shows a iridium electrode that comprises a iridium slug, an insulator, and a device substrate where this embodiment shows the iridium slug electrode flush with the extent of the insulator;
FIG. 10 b indicates an embodiment similar to that shown in FIGS. 10 / 12 a , however, the iridium slug is recessed from the insulator along its sides, but with its top flush with the insulator;
FIG. 10 c shows an embodiment with the iridium slug as in FIGS. 10 / 12 b ; however, the top of the iridium slug is recessed below the level of the insulator;
FIG. 10 d indicates an embodiment with the iridium slug coming to a point and insulation along its sides, as well as a being within the overall insulation structure;
FIG. 10 e indicates an embodiment of a method for fabricating and the fabricated iridium electrode where on a substrate of silicon an aluminum pad is deposited; on the pad the conductive adhesive is laid and platinum or iridium foil is attached thereby; a titanium ring is placed, sputtered, plated, ion implanted, ion beam assisted deposited (IBAD) or otherwise attached to the platinum or iridium foil; silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide or other insulator will adhere better to the titanium while it would not adhere as well to the platinum or iridium foil;
FIG. 11 a depicts a preferred electrode where it is formed on a silicon substrate and makes use of an aluminum pad, a metal foil such as platinum or iridium, conductive adhesive, a titanium ring, aluminum or zirconium oxide, an aluminum layer, and a mask;
FIG. 11 b shows an elongated electrode formed on the structure of FIG. 11 a with platinum electroplated onto the metal foil, the mask removed and insulation applied over the platinum electrode;
FIG. 11 c shows a variation of a form of the elongated electrode wherein the electrode is thinner and more recessed from the well sides;
FIG. 11 d shows a variation of a form of the elongated electrode wherein the electrode is squatter but recessed from the well sides;
FIG. 11 e shows a variation of a form of the elongated electrode wherein the electrode is a mushroom shape with the sides of its tower recessed from the well sides and its mushroom top above the oxide insulating material;
FIG. 12 a shows the coil attachment to two different conducting pads at an electrode nodes;
FIG. 12 b shows the coil attachment to two different conducting pads at an electrode node, together with two separate insulated conducting electrical pathways such as wires, each attached at two different electrode node sites on two different substrates;
FIG. 12 c shows an arrangement similar to that seen in FIGS. 12 / 16 d , with the difference that the different substrates are very close with a non-conducting adhesive between them and an insulator such as aluminum or zirconium oxide forms a connection coating over the two substrates, in part;
FIG. 12 d depicts an arrangement similar to that seen in FIGS. 12 / 16 c ; however, the connecting wires are replaced by an externally placed aluminum conductive trace;
FIG. 13 shows a hermetically sealed flip-chip in a ceramic or glass case with solder ball connections to hermetically sealed glass frit and metal leads;
FIG. 14 shows a hermetically sealed electronic chip as in FIG. 18 with the addition of biocompatible leads to pads on a remotely located electrode substrate;
FIG. 15 shows discrete capacitors on the electrode-opposite side of an electrode substrate;
FIG. 16 a shows an electrode-electronics retinal implant placed with the electrode half implanted beneath the retina, subretinally, while the electronics half projects above the retina, epiretinally;
FIG. 16 b shows another form of sub- and epi-retinal implantation wherein half of the electrode implant is epiretinal and half is subretinal;
FIG. 16 c shows the electrode parts are lined up by alignment pins or by very small magnets;
FIG. 16 d shows the electrode part lined up by template shapes which may snap together to hold the parts in a fixed relationship to each other;
FIG. 17 a shows the main screen of the physician's (local) controller (and programmer);
FIG. 17 b illustrates the pixel selection of the processing algorithm with the averaging of eight surrounding pixels chosen as one element of the processing;
FIG. 17 c represents an electrode scanning sequence, in this case the predefined sequence, A;
FIG. 17 d shows electrode parameters, here for electrode B, including current amplitudes and waveform timelines;
FIG. 17 e illustrates the screen for choosing the global electrode configuration, monopolar, bipolar, or multipolar;
FIG. 17 f renders a screen showing the definition of bipolar pairs (of electrodes);
FIG. 17 g shows the definition of the multipole arrangements;
FIG. 18 a illustrates the main menu screen for the palm-sized test unit;
FIG. 18 b shows a result of pressing on the stimulate bar of the main menu screen, where upon pressing the start button the amplitudes A 1 and A 2 are stimulated for times t 1 , t 2 , t 3 , and t 4 , until the stop button is pressed;
FIG. 18 c exhibits a recording screen that shows the retinal recording of the post-stimulus and the electrode impedance;
FIG. 19 shows the physician's remote controller that has the same functionality inside as the physician's controller but with the addition of communication means such as telemetry or telephone modem; and
FIG. 20 shows the patient's controller unit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is merely made for the purpose of describing the general principles of the invention. The scope of the invention should be determined with reference to the claims.
Objective
The objective of the embodiments of the current invention is a retinal color prosthesis to restore color vision, in whole or in part, by electrically stimulating undamaged retinal cells, which remain in patients with, lost or degraded visual function. Embodiments of this retinal color prosthesis invention are directed toward helping patients who have been blinded by degeneration of photoreceptors and other cells; but who have sufficient bipolar cells and the like to permit the perception of color vision by electric stimulation. By color vision, it is meant to include black, gray, and white among the term color.
General Description
Functionally, there are three main parts to an embodiment of this retinal color prosthesis invention. See FIG. 1 a . FIG. 1 a is oriented toward showing the main structural parts and subsystems, with a dotted enclosure to indicate a functional intercommunications aspect. The first part of the embodiment is external ( 1 ) to the eye. The second part is implanted internal ( 2 ) to the eye. The third part is means for communication between those two parts ( 3 ). Structurally there are two parts. One part is external ( 1 ) to the eye and the other part ( 2 ) is implanted within the eye. Each of these structural parts contains two way communication circuitry for communication ( 3 ) between the internal ( 2 ) and external ( 1 ) parts.
The external part of the retinal color prosthesis is carried by the patient. Typically, the external part including imager, video data processing unit, eye-tracker, and transmitter/receiver are worn as an eyeglass-like unit. Typical of this embodiment, a front view of one aspect of the structural external part ( 1 ) of the color retinal prosthesis is shown in FIG. 1 c and a side view is shown in FIG. 1 d , ( 1 ). In addition, there are two other units, which may be plugged into the external unit; when this is done they act as part of the external unit. The physician's control unit is not normally plugged into the external part worn by the patient, except when the physician is conducting an examination and adjustment of the retinal color prosthetic. The patient's controller may or may not be normally plugged in. When the patient's controller is plugged in, it can also receive signals from a remote physician's controller, which then acts in the same way as the plug-in physician's controller.
Examining further the embodiment of the subsystems of the external part, see FIG. 1 b . These include an external color imager ( 111 ), an eye-motion compensation system ( 112 ), a head-motion compensation system ( 131 ), a processing unit ( 113 ), a patient's controller ( 114 ), a physician's local controller ( 115 ), a physicians hand-held palm-size pocket-size unit ( 130 ), a physician's remote controller ( 117 ), and a telemetry means ( 118 ). The color imager is a color video camera such as a CCD or CMOS video camera. It gathers an image approximating what the eyes would be seeing if they were functional.
An external imager ( 111 ) sends an image in the form of electrical signals to the video data processing unit ( 113 ). The video data processing unit consists of microprocessor CPU's and associated processing chips including high-speed data signal processing (DSP) chips. This unit can format a grid-like or pixel-like pattern that is sent to the electrodes by way of the telemetry communication subsystems ( 118 , 121 ). See FIG. 1 b . In this embodiment of the retinal color prosthesis ( FIG. 1 b , ( 121 )), these electrodes are incorporated in the internal-to-the eye implanted part.
These electrodes, which are part of the internal implant ( 121 ), together with the telemetry circuitry ( 121 ) are inside the eye. With other internally implanted electronic circuitry ( 121 ), they cooperate with the electrodes so as to replicate the incoming pattern, in a useable form, for stimulation of the retina so as to reproduce a facsimile perception of the external scene. The eye-motion ( 112 ) and head-motion ( 131 ) detectors supply information to the video data processing unit ( 113 ) to shift the image presented to the retina ( 120 ).
There are three preferred embodiments for stimulating the retina via the electrodes to convey the perception of color. Color information is acquired by the imaging means ( 111 ). The color data is processed in the video data processing unit ( 113 ).
First Preferred Color Mode
Color information (See FIG. 2 a ), in the first preferred embodiment, is encoded by time sequences of pulses ( 201 ) separated by varying amounts of time ( 202 ), and also with the pulse duration being varied in time ( 203 ). The basis for the color encoding is the individual color code reference ( 211 through 217 ). The electrodes stimulate the target cells so as to create a color image for the patient, corresponding to the original image as seen by the video camera, or other imaging means. Using temporal coding of electrical stimuli placed (cf. FIG. 2 b , 220 , FIG. 2 c , 230 ) on or near the retina ( FIG. 2 b and FIG. 2 c , 221 , 222 ) the perception of color can be created in patients blinded by outer retinal degeneration. By sending different temporal coding schemes to different electrodes, an image composed of more than one color can be produced. FIG. 2 shows one stimulation protocol. Cathodic stimuli ( 202 ) are below the zero plane ( 220 ) and anodic stimuli ( 203 ) are above. All the stimulus rates are either “fast” ( 203 ) or “slow” ( 202 ) except for green ( 214 ), which includes an intermediate stimulus rate ( 204 ). The temporal codes for the other colors are shown as Red ( 211 ), as Magenta ( 212 ), as Cyan ( 213 ), as Yellow ( 215 ), as Blue ( 216 ), as Neutral ( 217 ). This preferred embodiment is directed toward electrodes which are less densely packed in proximity to the retinal cells.
Second Preferred Color Mode
Color information, in a second preferred embodiment, is sent from the video data processing unit to the electrode array, where each electrode has been determined by test to stimulate one of a bipolar type: red-center green-surround, green-center-red-surround, blue-center-yellow-surround, or yellow-center-blue-surround. In this embodiment, electrodes which are small enough to interact with a single cell, or at most, a few cells are placed in the vicinity of individual bipolar cells, which react to a stimulus with nerve pulse rates and nerve pulse structure (i.e., pulse duration and pulse amplitude). Some of the bipolar cells, when electrically, or otherwise, stimulated, will send red-green signals to the brain. Others will send yellow-blue signals. This refers to the operation of the normal retina. In the normal retina, red or green color photoreceptors (cone cells) send nerve pulses to the red-green bipolar cell which then pass some form of this information up to the ganglion cells and then up to the visual cortex of the brain. With small electrodes individual bipolar cells can be excited in a spatial, or planar, pattern. Small electrodes are those with tip from 0.1 μm to 15 μm, and which individual electrodes are spaced apart from a range 8 μm to 24 μm, so as to approximate a one-to-one correspondence with the bipolar cells. The second preferred embodiment is oriented toward a more densely packed set of electrodes.
Third Preferred Color Mode
A third preferred mode is a combination of the first and of the second preferred modes such that a broader area coverage of the color information encoded by time sequences of pulses, of varying widths and separations and with relatively fewer electrodes is combined with a higher density of electrodes, addressing more the individual bipolar cells.
First Order and Higher Effects
Regardless of a particular theory of color vision, the impinging of colored light on the normal cones, and possibly rods, give rise in some fashion to the perception of color, i.e., multi-spectral vision. In the time-pulse coding color method, above, the absence of all, or sufficient, numbers of working cones (and rods) suggests a generalization of the particular time-pulse color encoding method. The generalization is based on the known, or partly known, neuron conduction pathways in the retina. The cone cells, for example, signal to bipolar cells, which in turn signal the ganglion cells. The original spatial-temporal-color (including black, white) scheme for conveying color information as the cone is struck by particular wavelength photons is then transformed to a patterned signal firing of the next cellular level, say the bipolar cells, unless the cones are absent or don't function. Thus, this second level of patterned signal firing is what one wishes to supply to induce the perception of color vision.
The secondary layer of patterned firing may be close to the necessary primary pattern, in which case the secondary pattern (S) may be represented as P*(1+ò). The * indicates matrix multiplication. P is the primary pattern, represented as a matrix
P = [ p 11 p 1 j p k 1 p kj ]
where P represents the light signals of a particular spatial-temporal pattern, e.g., flicker signals for green. The output from the first cell layer, say the cones, is then S, the secondary pattern. This represents the output from the bipolar layer in response to the input from the first (cone) layer. If S=P*(1+ò), where 1 represents a vector and ò represents a small deviation applied to the vector 1, then S is represented by P to the lowest order, and by P*(1+ò) to the next order. Thus, the response may be seen as a zero order effect and a first order linear effect. Additional terms in the functional relationship are included to completely define the functional relationship. If S is some non-linear function of P, finding S by starting with P requires more terms then the linear case to define the bulk of the functional relationship. However, regardless of the details of one color vision theory or another, on physiological grounds S is some function of P. As in the case of fitting individual patients with lenses for their glasses, variations of parameters are expected in fitting each patient to a particular temporal coding of electrical stimuli.
Scaling Data from Photoreceptors to Bipolar Cells
As cited above, Greenberg (1998) indicates that electrical and photonic stimulation of the normal retina operate via similar mechanisms. Thus, even though electrical stimulation of a retina damaged by outer retinal degeneration is different from the electrical stimulation of a normal retina, the temporal relationships are expected to be analogous.
To explain this, it is noted that electrical stimulation of the normal retinal is accomplished by stimulating the photoreceptor cells (including the color cells activated differentially according to the color of light impinging on them). For the outer retinal degeneration, it is precisely these photoreceptor cells which are missing. Therefore, the electrical stimulation in this case proceeds by way of the cells next up the ladder toward the optic nerve, namely, the bipolar cells.
The time constant for stimulating photoreceptor is about 20 milliseconds. Thus the electrical pulse duration would need to be at least 20 milliseconds. The time constant for stimulating bipolar cells is around 9 seconds. These time constants are much longer than for the ganglion cells (about 1 millisecond). The ganglion cells are another layer of retinal cells closer to the optic nerve. The actual details of the behavior of the different cell types of the retina are quite complicated including the different relationships for current threshold versus stimulus duration (cf. Greenberg, 1998). One may, however, summarize an apparent resonant response of the cells based on their time constants corresponding to the actual pulse stimulus duration.
In FIG. 2 , which is extrapolated from external-to-the-eye electrical stimulation data of Young (1977) and from light stimulation data of Festinger, Allyn, and White (1971), there is shown data that would be applicable to the photoreceptor cells. One may scale the data down based on the ratio of the photoreceptor time constant (about 20 milliseconds) to that of the bipolar cells (about 9 milliseconds). Consequently, 50 milliseconds on the time scale in FIG. 2 now corresponds to 25 milliseconds. Advantageously, stimulation rates and duration of pulses, as well as pulse widths may be chosen which apply to the electrode stimulation of the bipolar cells of the retina.
Eye Movement/Head Motion Compensation
In a preferred embodiment, an external imager such as a color CCD or color CMOS video camera ( 111 ) and a video data processing unit ( 113 ), with an external telemetry unit ( 118 ) present data to the internal eye-implant part. Another aspect of the preferred embodiment is a method and apparatus for tracking eye movement ( 112 ) and using that information to shift ( 113 ) the image presented to the retina. Another aspect of the preferred embodiment utilizes a head motion sensor ( 131 ) and a head motion compensation system ( 131 , 113 ). The video data processing unit incorporates the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion. Thus electronic image compensation, stabilization and adjustment are provided by the eye and head movement compensation subsystems of the external part of the retinal color prosthesis.
Logarithmic Encoding of Light
In one aspect of an embodiment ( FIG. 1 b ), light amplitude is recorded by the external imager ( 111 ). The video data processing unit uses a logarithmic encoding scheme ( 113 ) to convert the incoming light amplitudes into the logarithmic electrical signals of these amplitudes ( 113 ). These electrical signals are then passed on by telemetry ( 118 ), ( 121 ), to the internal implant ( 121 ) which results in the retinal cells ( 120 ) being stimulated via the implanted electrodes ( 121 ), in this embodiment as part of the internal implant ( 121 ). Encoding is done outside the eye, but may be done internal to the eye, with a sufficient internal computational capability.
Energy and Signal Transmission
Coils
The retinal prosthesis system contains a color imager ( FIG. 1 b , 111 ) such as a color CCD or CMOS video camera. The imaging output data is typically processed ( 113 ) into a pixel-based format compatible with the resolution of the implanted system. This processed data ( 113 ) is then associated with corresponding electrodes and amplitude and pulse-width and frequency information is sent by telemetry ( 118 ) into the internal unit coils, ( 311 ), ( 313 ), ( 314 ) (see FIG. 3 a ). Electromagnetic energy, is transferred into and out from an electronic component ( 311 ) located internally in the eye ( 312 ), using two insulated coils, both located under the conjunctiva of the eye with one free end of one coil ( 313 ) joined to one free end of the second coil ( 314 ), the second free end of said one coil joined to the second free end of said second coil. The second coil ( 314 ) is located in proximity to a coil ( 311 ) which is a part of said internally located electronic component, or, directly to said internally located electronic component ( 311 ). The larger coil is positioned near the lens of the eye. The larger coil is fastened in place in its position near the lens of the eye, for example, by suturing. FIG. 3 b represents an embodiment of the telemetry unit temporally located near the eye, including an external temporal coil ( 321 ), an internal (to the eye) coil ( 314 ), an external-to-the-eye electronic chip ( 320 ), dual coil transfer units ( 314 , 323 ), ( 321 , 322 ) and an internal-to-the-eye electrode array ( 325 ). The advantage of locating the external electronics in the fatty tissue behind the eye is that there is a reasonable amount of space there for the electronics and in that position it appears not to interfere with the motion of the eye.
Ultrasonic Sound
In another aspect the information coding is done with ultrasonic sound and in a third aspect information is encoded by modulating light. An ( FIG. 3 c ) ultrasonic transducer ( 341 ) replaces the electromagnetic wave receiving coil on the implant ( 121 ) inside the eye. An ultrasonic transducer ( 342 ) replaces the coil outside the eye for the ultrasonic case. A transponder ( 343 ) under the conjunctiva of the eye may be used to amplify the acoustic signal and energy either direction. By piezoelectric effects, the sound vibration is turned into electrical current, and energy extracted therefrom.
Modulated Light Beam
For the light modulation ( FIG. 3 d ) case, a light emitting diode (LED) or laser diode or other light generator ( 361 ), capable of being modulated, acts as the information transmitter. Information is transferred serially by modulating the light beam, and energy is extracted from the light signal after it is converted to electricity. A photo-detector ( 362 ), such as a photodiode, which turns the modulated light signal into a modulated electrical signal, is used as a receiver. A set of a photo-generator and a photo-detector are on the implant ( 121 ) and a set is also external to the eye.
Prototype-Like Device
FIG. 4 shows an example of the internal-to-the-eye and the external-to-the eye parts of the retinal color prosthesis, together with a means for communicating between the two. The video camera ( 401 ) connects to an amplifier ( 402 ) and to a microprocessor ( 403 ) with memory ( 404 ). The microprocessor is connected to a modulator ( 405 ). The modulator is connected to a coil drive circuit ( 406 ). The coil drive circuit is connected to an oscillator ( 407 ) and to the coil ( 408 ). The coil ( 408 ) can receive energy inductively, which can be used to recharge a battery ( 410 ), which then supplies power. The battery may also be recharged from a charger ( 409 ) on a power line source ( 411 ).
The internal-to-the eye implanted part shows a coil ( 551 ), which connects to both a rectifier circuit ( 552 ) and to a demodulator circuit ( 553 ). The demodulator connects to a switch control unit ( 554 ). The rectifier ( 552 ) connects to a plurality of diodes ( 555 ) which rectify the current to direct current for the electrodes ( 556 ); the switch control sets the electrodes as on or off as they set the switches ( 557 ). The coils ( 408 ) and ( 551 ) serve to connect inductively the internal-to-the-eye ( 500 ) subsystem and the external-to-the patient ( 400 ) subsystem by electromagnetic waves. Both power and information can be sent into the internal unit. Information can be sent out to the external unit. Power is extracted from the incoming electromagnetic signal and may be accumulated by capacitors connected to each electrode or by capacitive electrodes themselves.
Simple Electrode Implant
FIG. 6 a illustrates a set of round monopolar electrodes ( 602 ) on a substrate material ( 601 ). FIG. 7 shows the corresponding indifferent electrode ( 702 ) for these monopolar electrodes, on a substrate ( 701 ), which may be the back of ( 601 ). FIG. 6 b shows a bipolar arrangement of electrodes, both looking down onto the plane of the electrodes, positive ( 610 ) and negative ( 611 ), and also looking at the electrodes sideways to that view, positive ( 610 ) and negative ( 611 ), sitting on their substrate ( 614 ). Similarly for FIG. 6 c where a multipole triplet is shown, with two positive electrodes ( 621 ) and one negative electrode, looking down on their substrate plane, and looking sideways to that view, also showing the substrate ( 614 ).
Epiretinal Electrode Array
FIG. 8 a depicts the location of an epiretinal electrode array ( 811 ) located inside the eye ( 812 ) in the vitreous humor ( 813 ) located above the retina ( 814 ), toward the lens capsule ( 815 ) and the aqueous humor ( 816 );
One aspect of the present embodiment, shown in FIG. 8 b , is the internal retinal color prosthetic part, which has electrodes ( 817 ) which may be flat conductors that are recessed in an electrical insulator ( 818 ). One flat conductor material is a biocompatible metallic foil ( 817 ). Platinum foil is a particular type of biocompatible metal foil. The electrical insulator ( 818 ) in one aspect of the embodiment is silicone.
The silicone ( 818 ) is shaped to the internal curvature of the retina ( 814 ). The vitreous humor ( 813 ), the conductive solution naturally present in the eye, becomes the effective electrode since the insulator ( 818 ) confines the field lines in a column until the current reaches the retina ( 814 ). A further advantage of this design is that the retinal tissue ( 814 ) is only in contact with the insulator ( 818 ), such as silicone, which may be more inactive, and thus, more biocompatible than the metal in the electrodes. Advantageously, another aspect of an embodiment of this invention is that adverse products produced by the electrodes ( 817 ) are distant from the retinal tissue ( 814 ) when the electrodes are recessed.
FIG. 8 c shows elongated epiretinal electrodes ( 817 ). The electrically conducting electrodes ( 817 ) are contained within the electrical insulation material ( 818 ); a silicon chip ( 819 ) acts as a substrate. The electrode insulator device ( 818 ) is shaped so as to contact the retina ( 814 ) in a conformal manner.
Subretinal Electrode Array
FIG. 9 a shows the location of a subretinal electrode array ( 811 ) below the retina ( 814 ), away from the lens capsule ( 815 ) and the aqueous humor ( 816 ). The retina ( 814 ) separates the subretinal electrode array from the vitreous humor ( 813 ). FIG. 9 b illustrates the subretinal electrode array ( 811 ) with pointed elongated electrodes ( 817 ), the insulator ( 818 ), and the silicon chip ( 819 ) substrate. The subretinal electrode array ( 811 ) is in conformal contact with the retina ( 814 ) with the electrodes ( 817 ) elongated to some depth.
Electrodes
Iridium Electrodes
Now FIG. 10 will illuminate structure and manufacture of iridium electrodes ( FIGS. 10 a - e ). FIG. 10 a shows an iridium electrode, which comprises an iridium slug ( 1011 ), an insulator ( 1012 ), and a device substrate ( 1013 ). This embodiment shows the iridium slug electrode flush with the extent of the insulator. FIG. 10 b indicates an embodiment similar to that shown in FIG. 10 a , however, the iridium slug ( 1011 ) is recessed from the insulator ( 1012 ) along its sides, but with its top flush with the insulator. When the iridium electrodes ( 1011 ) are recessed in the insulating material ( 1012 ), they may have the sides exposed so as to increase the effective surface area without increasing geometric area of the face of the electrode. If an electrode ( 1011 ) is not recessed it may be coated with an insulator ( 1012 ), on all sides, except the flat surface of the face ( 1011 ) of the electrode. Such an arrangement can be embedded in an insulator that has an overall profile curvature that follows the curvature of the retina. The overall profile curvature may not be continuous, but may contain recesses, which expose the electrodes.
FIG. 10 c shows an embodiment with the iridium slug as in FIG. 10 b , however, the top of the iridium slug ( 1011 ) is recessed below the level of the insulator; FIG. 10 d indicates an embodiment with the iridium slug ( 1011 ) coming to a point and insulation along its sides ( 1021 ), as well as a being within the overall insulation structure ( 1021 ). FIG. 10 e indicates an embodiment of a method for fabricating the iridium electrodes. On a substrate ( 1013 ) of silicon, an aluminum pad ( 1022 ) is deposited. On the pad, the conductive adhesive ( 1023 ) is laid and platinum or iridium foil ( 1024 ) is attached thereby. A titanium ring ( 1025 ) is placed, sputtered, plated, ion implanted, ion beam assisted deposited (IBAD) or otherwise attached to the platinum or iridium foil ( 1024 ). Silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1012 ) or other insulator can adhere better to the titanium ( 1025 ) while it would not otherwise adhere as well to the platinum or iridium foil ( 1024 ). The depth of the well for the iridium electrodes ranges from 0.1 μm to 1 mm.
Elongated Electrodes
Another aspect of an embodiment of the invention is the elongated electrode, which are designed to stimulate deeper retinal cells, in one embodiment, by penetrating the retina. By getting closer to the target cells for stimulation, the current required for stimulation is lower and the focus of the stimulation is more localized. The lengths chosen are 100 microns through 500 microns, including 300 microns. FIG. 8 c is a rendering of an elongated epiretinal electrode array with the electrodes shown as pointed electrical conductors ( 817 ), embedded in an electrical insulator ( 818 ), where the elongated electrodes ( 817 ) contact the retina in a conformal manner, however, penetrating into the retina ( 814 ).
These elongated electrodes, in an aspect of this of an embodiment of the invention may be of all the same length. In a different aspect of an embodiment, they may be of different lengths. Said electrodes may be of varying lengths ( FIG. 8 , 817 ), such that the overall shape of said electrode group conforms to the curvature of the retina ( 814 ). In either of these cases, each may penetrate the retina from an epiretinal position ( FIG. 8 a , 811 ), or, in a different aspect of an embodiment of this invention, each may penetrate the retina from a subretinal position ( FIG. 9 b , 817 ).
One method of making the elongated electrodes is by electroplating with one of an electrode material, such that the electrode, after being started, continuously grows in analogy to a stalagmite or stalactite. The elongated electrodes are 100 to 500 microns in length, the thickness of the retina averaging 200 microns. The electrode material is a substance selected from the group consisting of pyrolytic carbon, titanium nitride, platinum, iridium oxide, and iridium. The insulating material for the electrodes is a substance selected from the group silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide.
Platinum Electrodes
FIG. 11 ( a - e ) demonstrates a preferred structure of, and method of, making, spiked and mushroom platinum electrodes. Examining FIG. 11 a , one sees that the support for the flat electrode ( 1103 ) and other components such as electronic circuits (not shown) on the silicon substrate ( 1101 ). An aluminum pad ( 1102 ) is placed where an electrode or other component is to be placed. In order to hermetically seal-off the aluminum and silicon from any contact with biological activity, a metal foil ( 1103 ), such as platinum or iridium, is applied to the aluminum pad ( 1102 ) using conductive adhesive ( 1104 ). Electroplating is not used since a layer formed by electroplating, in the range of the required thinness, has small-scale defects or holes which destroy the hermetic character of the layer. A titanium ring ( 1105 ) is next placed on the platinum or iridium foil ( 1103 ). Normally, this placement is by ion implantation, sputtering or ion beam assisted deposition (IBAD) methods. Silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1106 ) is placed on the silicon substrate ( 1101 ) and the titanium ring ( 1105 ). In one embodiment, an aluminum layer ( 1107 ) is plated onto exposed parts of the titanium ring ( 1105 ) and onto the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1106 ). In this embodiment, the aluminum ( 1107 ) layer acts as an electrical conductor. A mask ( 1108 ) is placed over the aluminum layer ( 1107 ).
In forming an elongated, non-flat, electrode ( FIG. 11 b ), platinum is electroplated onto the platinum or iridium foil ( 1103 ). Subsequently, the mask ( 1108 ) is removed and insulation ( 1110 ) is applied over the platinum electrode ( 1109 ).
In FIG. 11 c , a platinum electrode ( 1109 ) is shown which is more internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring. The electrode ( 1109 ) is also thinner and more elongated and more pointed. FIG. 11 d shows a platinum electrode formed by the same method as was used in FIGS. 11 a , 11 b , and 11 c . The platinum electrode ( 1192 ) is more internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring as was the electrode ( 1109 ) in FIG. 11 c . However it is less elongated and less pointed.
The platinum electrode is internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring; said electrode whole angle at it's peak being in the range from 1° to 120°; the base of said conical or pyramidal electrode ranging from 1 micron to 500 micron; the linear section of the well unoccupied by said conical or pyramidal electrode ranging from zero to one-third.
A similar overall construction is depicted in FIG. 11 e . The electrode ( 1193 ), which may be platinum, is termed a mushroom shape. The maximum current density for a given metal is fixed. The mushroom shape presents a relatively larger area than a conical electrode of the same height. The mushroom shape advantageously allows a higher current, for the given limitation on the current density (e.g., milliamperes per square millimeter) for the chosen electrode material, since the mushroom shape provides a larger area.
Inductive Coupling Coils
Information transmitted electromagnetically into or out of the implanted retinal color prosthesis utilizes insulated conducting coils so as to allow for inductive energy and signal coupling. FIG. 12 b shows an insulated conducting coil and insulated conducting electrical pathways, e.g., wires, attached to substrates at what would otherwise be electrode nodes, with flat, recessed metallic, conductive electrodes ( 1201 ). In referring to wire or wires, insulated conducting electrical pathways are included, such as in a “two-dimensional” “on-chip” coil or a “two-dimensional” coil on a polyimide substrate, and the leads to and from these “two-dimensional” coil structures. A silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1204 ) is shown acting as both an insulator and an hermetic seal. Another aspect of the embodiment is shown in FIG. 12 d . The electrode array unit ( 1201 ) and the electronic circuitry unit ( 1202 ) can be on one substrate, or they may be on separate substrates ( 1202 ) joined by an insulated wire or by a plurality of insulated wires ( 1203 ). Said separate substrate units can be relatively near one another. For example, they might lie against a retinal surface, either epiretinally or subretinally placed. Two substrates units connected by insulated wires may carry more electrodes than if only one substrate with electrodes was employed, or it might be arranged with one substrate carrying the electrodes, the other the electronic circuitry. Another arrangement has the electrode substrate or substrates placed in a position to stimulate the retinal cells, while the electronics are located closer to the lens of the eye to avoid heating the sensitive retinal tissue.
In all of the FIGS. 12 a , 12 b , and 12 c , a coil ( 1205 ) is shown attached by an insulated wire. The coil can be a coil of wire, or it can be a “two dimensional” trace as an “on-chip” component or as a component on polyimide. This coil can provide a stronger electromagnetic coupling to an outside-the-eye source of power and of signals. FIG. 12 c shows an externally placed aluminum (conductive) trace instead of the electrically conducting wire of FIG. 12 d . Also shown is an electrically insulating adhesive ( 1208 ) which prevents electrical contact between the substrates ( 1202 ) carrying active circuitry ( 1209 ).
Hermetic Sealing
Hermetic Coating
All structures, which are subject to corrosive action as a result of being implanted in the eye, or, those structures which are not completely biocompatible and not completely safe to the internal cells and fluids of the eye require hermetic sealing. Hermetic sealing may be accomplished by coating the object to be sealed with silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide. These materials also provide electrical insulation. The method and apparatus of hermetic sealing by aluminum and zirconium oxide coating is described in U.S. patent application Ser. No. 08/994,515, now U.S. Pat. No. 6,043,437. The methods of coating a substrate material with the hermetic sealant include sputtering, ion implantation, and ion-beam assisted deposition (IBAD).
Hermetic Box
Another aspect of an embodiment of the invention is hermetically sealing the silicon chip ( 1301 ) by placing it in a metal or ceramic box ( 1302 ) of rectangular cross-section with the top and bottom sides initially open ( FIG. 13 ). The box may be of one ( 1302 ) of the metals selected from the group comprising platinum, iridium, palladium, gold, and stainless steel. Solder balls ( 1303 ) are placed on the “flip-chip”, i.e., a silicon-based chip that has the contacts on the bottom of the chip ( 1301 ). Metal feedthroughs ( 1304 ) made from a metal selected from the group consisting of radium, platinum, titanium, iridium, palladium, gold, and stainless steel. The bottom cover ( 1306 ) is formed from one of the ceramics selected from the group consisting of aluminum oxide or zirconium oxide. The inner surface ( 1305 ), toward the solder ball, ( 1303 ) of the feed-through ( 1304 ) is plated with gold or with nickel. The ceramic cover ( 1306 ) is then attached to the box using a braze ( 1307 ) selected from the group consisting of: 50% titanium together with 50% nickel and gold. Electronics are then inserted and the metal top cover (of the same metal selected for the box) is laser welded in place.
Separate Electronics Chip Substrate and Electrode Substrate
In one embodiment of the invention ( FIG. 14 ), the chip substrate ( 1401 ) is hermetically sealed in a case ( 1402 ) or by a coating of the aluminum, zirconium, or magnesium oxide coating. However, the electrodes ( 1403 ) and its substrate ( 1404 ) form a distinct and separate element. Insulated and hermetically sealed wires ( 1405 ) connect the two. The placement of the electrode element may be epiretinal, while the electronic chip element may be relatively distant from the electrode element, as much distant as being in the vicinity of the eye lens. Another embodiment of the invention has the electrode element placed subretinally and the electronic chip element placed toward the rear of the eye, being outside the eye, or, being embedded in the sclera of the eye or in or under the choroid, blood support region for the retina. Another embodiment of the invention has the electronic chip element implanted in the fatty tissue behind the eye and the electrode element placed subretinally or epiretinally.
Capacitive Electrodes
A plurality of capacitive electrodes can be used to stimulate the retina, in place of non-capacitive electrodes. A method of fabricating said capacitive electrode uses a pair of substances selected from the pair group consisting of the pairs iridium and iridium oxide; and, titanium and titanium nitride. The metal electrode acts with the insulating oxide or nitride, which typically forms of its own accord on the surface of the electrode. Together, the conductor and the insulator form an electrode with capacitance.
Mini-capacitors ( FIG. 15 ) can also be used to supply the required isolating capacity. The capacity of the small volume size capacitors ( 1501 ) is 0.47 microfarads. The dimensions of these capacitors are individually 20 mils (length) by 20 mils (width) by 40 mils (height). In one embodiment of the invention, the capacitors are mounted on the surface of a chip substrate ( 1502 ), that surface being opposite to the surface containing the active electronics elements of the chip substrate.
Electrode/Electronics Component Placement
In one embodiment ( FIG. 16 a ), the internal-to-the-eye implanted part consists of two subsystems, the electrode component 1602 , including electrodes 1603 , subretinally positioned and the electronic component 1601 epiretinally positioned and connected by cables 1604 . The electronics component 1601 , with its relatively high heat dissipation, is positioned at a distance, within the eye, from the electrode component 1602 placed near the retina 1605 that is sensitive to heat.
An alternative embodiment shown in FIG. 16 b is where one of the combined electronic and electrode substrate units 1611 is positioned subretinally and the other is located epiretinally 1610 and both are held together across the retina so as to efficiently stimulate bipolar and associated cells in the retina 1605 .
An alternative embodiment of the invention has the electronic chip element implanted in the fatty tissue behind the eye and the electrode element placed subretinally or epiretinally, and power and signal communication between them by electromagnetic means including radio-frequency (rf), optical, and quasi-static magnetic fields, or by acoustic means including ultrasonic transducers.
FIG. 16 c shows how the two electronic-electrode substrate units are held positioned in a prescribed relationship to each other by small magnets. Alternatively the two electronic-electrode substrate units are held in position by alignment pins. Another aspect of this is to have the two electronic-electrode substrate units held positioned in a prescribed relationship to each other by snap-together mating parts, some exemplary ones being shown in FIG. 16 d.
Neurotrophic Factor
Another aspect of the embodiment is the use of a neurotrophic factor, for example, Nerve Growth Factor, applied to the electrodes, or to the vicinity of the electrodes, to aid in attracting target nerves and other nerves to grow toward the electrodes.
Eye-Motion Compensation System
Another aspect of the embodiment is an eye-motion compensation system comprising an eye-movement tracking apparatus ( FIG. 1 b , 112 ); measurements of eye movement; a transmitter to convey said measurements to video data processor unit that interprets eye movement measurements as angular positions, angular velocities, and angular accelerations; and the processing of eye position, velocity, acceleration data by the video data processing unit for image compensation, stabilization and adjustment.
Ways of eye-tracking ( FIG. 1 b , 112 ) include utilizing the corneal eye reflex, utilizing an apparatus for measurements of electrical activity where one or more coils are located on the eye and one or more coils are outside the eye, utilizing an apparatus where three orthogonal coils placed on the eye and three orthogonal coils placed outside the eye, utilizing an apparatus for tracking movements where electrical recordings from extra-ocular muscles are measured and conveyed to the video data processing unit that interprets such electrical measurements as angular positions, angular velocities, and angular accelerations. The video data processing unit uses these values for eye position, velocity, and acceleration to compute image compensation, stabilization and adjustment data, which is then applied by the video data processor to the electronic form of the image.
Head Sensor
Another aspect of the embodiment utilizes a head motion sensor ( 131 ). The basic sensor in the head motion sensor unit is an integrating accelerometer. A laser gyroscope can also be used. A third sensor is the combination of an integrating accelerometer and a laser gyroscope. The video data processing unit can incorporate the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion.
Physician's Local Control Unit
Another aspect includes a retinal prosthesis with (see FIG. 1 b ) a physician's local external control unit ( 115 ) allowing the physician to exert setup control of parameters such as amplitudes, pulse widths, frequencies, and patterns of electrical stimulation. The physician's control unit ( 115 ) is also capable of monitoring information from the implanted unit ( 121 ) such as electrode current, electrode impedance, compliance voltage, and electrical recordings from the retina. The monitoring is done via the internal telemetry unit, electrode and electronics assembly ( 121 ).
An important aspect of setting up the retinal color prosthesis is setting up electrode current amplitudes, pulse widths, and frequencies so they are comfortable for the patient. FIGS. 17 a - c and FIGS. 18 a - c illustrate some of the typical displays. A computer-controlled stimulating test that incorporates patient response to arrive at optimal patient settings may be compared to being fitted for eyeglasses, first determining diopter, then cylindrical astigmatic correction, and so forth for each patient. The computer uses interpolation and extrapolation routines. Curve or surface or volume fitting of data may be used. For each pixel, the intensity in increased until a threshold is reached and the patient can detect something in his visual field. The intensity is further increased until the maximum comfortable brightness is reached. The patient determines his subjective impression of one-quarter maximum brightness, one-half maximum brightness, and three-quarters maximum brightness. Using the semi-automated processing of the patient-in-the-loop with the computer, the test program runs through the sequences and permutations of parameters and remembers the patient responses. In this way apparent brightness response curves are calibrated for each electrode for amplitude. Additionally, in the same way as for amplitude, pulse width and pulse rate (frequency), response curves are calibrated for each patient. The clinician can then determine what the best settings are for the patient.
This method is generally applicable to many, if not all, types of electrode based retinal prostheses. Moreover, it also is applicable to the type of retinal prosthesis, which uses an external light intensifier shining upon essentially a spatially distributed set of light sensitive diodes with a light activated electrode. In this latter case, a physician's test, setup and control unit is applied to the light intensifier which scans the implanted photodiode array, element by element, where the patient can give feedback and so adjust the light intensifier parameters.
Remote Physician's Unit
Another aspect of an embodiment of this invention includes (see FIG. 1 b ) a remote physician control unit ( 117 ) that can communicate with a patient's unit ( 114 ) over the public switched telephone network or other telephony means. This telephone-based pair of units is capable of performing all of the functions of the of the physician's local control unit ( 115 ).
Physician's Unit Measurements, Menus and Displays
Both the physician's local ( 115 ) and the physician's remote ( 117 ) units always measure brightness, amplitudes, pulse widths, frequencies, patterns of stimulation, shape of log amplification curve, electrode current, electrode impedance, compliance voltage and electrical recordings from the retina.
FIG. 17 a shows the main screen of the Physician's Local and Remote Controller and Programmer. FIG. 17 b illustrates the pixel selection of the processing algorithm with the averaging of eight surrounding pixels chosen as one element of the processing. FIG. 17 c represents an electrode scanning sequence, in this case the predefined sequence, A. FIG. 17 d shows electrode parameters, here for electrode B, including current amplitudes and waveform timelines. FIG. 17 e illustrates the screen for choosing the global electrode configuration, monopolar, bipolar, or multipolar. FIG. 17 f renders a screen showing the definition of bipolar pairs (of electrodes). FIG. 17 g shows the definition of the multipole arrangements.
FIG. 18 a illustrates the main menu screen for the palm-sized test unit. FIG. 18 b shows a result of pressing on the stimulate bar of the (palm-sized unit) main menu screen, where upon pressing the start button the amplitudes A 1 and A 2 are stimulated for times t 1 , t 2 , t 3 , and t 4 , until the stop button is pressed. FIG. 18 c exhibits a recording screen that shows the retinal recording of the post-stimulus and the electrode impedance.
FIGS. 19 a , 19 b and 19 c show different embodiments of the Physician's Remote Controller, which has the same functionality inside as the Physician's Local Controller but with the addition of communication means such as telemetry or telephone modem.
Patient's Controller
Corresponding to the Physician's Local Controller, but with much less capability, is the Patient's Controller. FIG. 20 shows the patient's local controller unit. This unit can monitor and adjust brightness ( 2001 ), contrast ( 2002 ) and magnification ( 2003 ) of the image on a non-continuous basis. The magnification control ( 2003 ) adjusts magnification both by optical zoom lens control of the lens for the imaging means ( FIG. 1 , 111 ), and by electronic adjustment of the image in the data processor ( FIG. 2 , 113 ).
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. | The present invention is an implantable visual prosthesis where the neural stimulator includes an electrode array body suitable to be placed in an epiretinal location with insulation covering the electrode array body and forming voids. Electrodes are recessed within those voids. | 0 |
BACKGROUND OF THE INVENTION
This invention relates generally to survival during earthquakes in local, accessible shelters quickly usable at the beginning of earthquakes and during their continuance.
There is need for efficient, durable and highly accessible shelters installable in buildings for rapid access and use during earthquakes.
In particular, there is need for portable shelters as described herein having the multiple functions and very desirable elements to be described herein.
SUMMARY OF THE INVENTION
It is a major object of the invention to provide an improved protective shelter, easily installable in a building structure, for rapid access and use during an earthquake. Basically the shelter comprises:
a) a container sized for human occupancy, the container having walls and an access opening and a quickly openable and closable primary door to cover and uncover said opening,
b) the container walls and door consisting of high strength panel material, in excess of 10,000 psi load resistance, the wall or walls being resiliently flexible,
c) the container supported for sliding movement compensating for earthquake induced sideward movement of a supporting surface,
d) shock or impact absorbing cushioning means at the container interior, to cushion sudden movement of an occupant relative to the container as the container is suddenly moved by earthquake transmitted force.
In this regard, provision may be made to cushion vertical, i.e. up and down earthquake induced movement of the container, operating in conjunction with sideward sliding compensation, and to move the containers relative to debris at the exterior.
As will be seen, the door is constructed to easily slide open and closed at a side of the container; and a secondary door may be provided for use and during escape from the container, and is easily openable by an occupant of the container chamber in the event the primary door becomes inoperable as by jamming of building debris against the container.
Another object is to provide shelter walls constructed of non-metallic, high strength fireproof material such as
i) flexible DELRIN, ii) flexible KEVLAR, iii) high density polyethylene, preferably injected with structural foam.
A further object is to provide a storage sub-container contained within the container, the sub-container having wall structure consisting of high strength panel material and being accessible to an occupant of the container.
Yet another object is to provide a durable window or windows provided in container walls enabling occupant viewing of building debris adjacent or spaced from the container to provide an escape path or route. Also, an openable and closable air vent is provided in a container high strength wall or panel. A high strength storage area is provided in the container, as for example a high strength wall, for equipment such as
i) communication equipment, ii) a cell phone or phones, iii) edibles, iv) illumination equipment, v) oxygen supply means.
Walls of the container are of sufficient thickness and size to withstand shock loads to be encountered during building destruction during an earthquake.
These and other objects and advantages of the invention, as for example are listed in the claims, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which:
DRAWING DESCRIPTION
FIG. 1 is a perspective view of a preferred apparatus;
FIGS. 2 and 3 are fragmentary views of window and air vent components provide in a high strength wall;
FIG. 4 is a section in elevation showing features of shelter construction;
FIG. 5 is a view like FIG. 4 , showing further details of shelter construction;
FIG. 6 is a section taken in elevation on lines 6 - 6 of FIG. 5 ;
FIG. 7 shows a combined vertical cushioning, and lateral sliding compensation, mechanism;
FIG. 8 is an elevation view showing a shelter consisting of resilient, impact resistant, high strength material;
FIG. 9 is a side view of a container wall with an accessible pusher;
FIG. 10 is a section taken on lines 10 - 10 of FIG. 9 , showing occupant use of a pusher advancing tool, to affect shelter displacement;
FIG. 11 is a section showing an elongated pusher;
FIG. 12 is a section showing a container shelter wall-sliding door installation;
FIG. 13 is a view like FIG. 12 , but with addition of a pivoted auxiliary door in case of damage to the sliding door;
FIG. 14 shows the auxiliary door in pivoted position; and
FIGS. 15-17 show further details of container construction.
DETAILED DESCRIPTION
In the drawings, showing a preferred example, the earthquake shelter 100 is shown to comprise a longitudinally elongated container 10 sized for human occupancy, and including elongated top and bottom walls or panels 11 and 12 , supported by elongated upright laterally spaced front and rear walls 13 and 14 , and end walls or panels 15 and 16 . Such walls may typically be between 1 and 2 inches thick and consist of very high strength material such as KEVLAR, DELRIN or polycarbonate sheet plastic material. Corners may be connected by fasteners as at 20 seen in FIG. 4 . Alternatively, the panels may be integrally connected at corners, as during molding. A building floor is schematically indicated at 22 , and an overhead building horizontal structure at 23 , these being subject to collapse, or partial collapse during an earthquake, with falling debris striking the shelter 10 constructed to withstand such impact. Low friction slider plates 24 are connected to the bottom panel 12 , at its corners, and serve to allow limited sliding of the shelter, laterally or horizontally, to compensate for earthquake induced lateral motion transmitted as by building floor 22 .
FIG. 7 shows provision of a dash-pot type cushioning means 80 , operating to cushion i.e. dampen, vertical motion of the container, in conjunction with slider plate compensation for lateral motion. One such means 80 as shown in FIG. 7 , includes at one or more corners of the container, a helical spring 81 installed in a recess 83 in the container, and confined between recess interior wall 85 and the top surface 24 a of plate 24 . The spring frictionally rubs against recess side wall 83 a as the spring is compressively displaced endwise, due to impact loading on and displacement of the container, clamping container displacement. See also plunger 95 rubbing against bore 96 as the spring compresses, and also acting as a vertical guide.
The panel 13 forms or defines a front opening 30 sized to permit rapid human access or entry into the container interior 31 , for shelter during at least part of the earthquake motion, as during at least the debris falling stage, near the end of the earthquake. The container interior contains yieldable cushioning material 33 indicated at one more locations 33 a , 33 b , 33 c , 33 d , 33 e and 33 f , adjacent the inward facing surfaces of the container walls. Such material serves to cushion sudden relative movement of an occupant and the container, as the container is suddenly moved in response to earthquake transmitted force, or by impact of falling debris. Material 33 may consist of textile or plastic blanketing, batting or other material, of thickness between 2 and 5 inches, for example.
A primary door 36 is manually movable from the container interior to open and close the access opening 30 , for protection. See door edge slider guides at 36 a , and grooves 36 b in FIG. 6 . A supply 37 of the cushioning material at the container interior, may be used to lay against the door interior surface, for cushioning protection, against sudden movement, as referred to. An air vent in at least one wall, as at 38 in wall 14 , may be opened or closed from the container interior, as by use of adhesive tape 39 or other means, shown in FIG. 3 .
A small observation window or windows 41 is or are preferably provided in one or more container walls, as shown in one or more upright walls 13 , 15 and 16 , and also in sliding door 36 . Such windows may consist of high strength transparent plastic, or glass, edge anchored or molded to the panels, as during panel formation.
A secondary door is provided, as at 50 , in the container, and allows occupant escape in the event the primary door is not openable due to jamming, or debris collection at the front side of the primary door 36 . Door 50 is shown for example adjacent the end panel 16 in FIG. 5 , to close secondary opening 51 . It may be carried by a metallic rod 50 a extending horizontally, inwardly of panel 16 , to allow swinging of the door plate 50 b inwardly and upwardly, exposing opening 51 . Normally, the door 50 is retained closed, adjacent opening 51 , as by an L-shaped (or other) retainer 62 , which is rotatable or twistable to release door retention for upward swinging. Cushioning material 54 is attached to the inner side of door 50 .
FIGS. 5 and 6 show provision of a storage or sub-container 60 integral with wall 13 at the inner side of that wall. The sub-container consists of high strength panel material and is readily accessible to an occupant of the shelter. The sub-container is shown as upwardly open at entrance 63 , for downward reception of useful articles or components 64 , such as
flashlight cell phone radio equipment edibles and water first aid supplies sound emitters such as siren, beepers, etc., for indicating shelter position, for rescue oxygen supply or compressed air bottle.
Additional optional features include:
a) container top surface 70 serving as furniture surface; see also top horizontal extension flanges 71 ,
b) provision of multiple such containers at different floor levels in building,
c) bedding and clothing supply in the container,
d) human waste disposal means, as in a pouch receivable in the sub-container.
Referring to FIG. 8 , it shows a box-like container 150 having top and bottom walls 151 and 152 ; end walls 153 and 154 ; and front and back walls 155 and 156 all consisting of plastic such as foam. Convex or rounded wall junctions are shown as at 157 , adding to resilient strength of the walls as during an earthquake. Resilient deflections during heavy impact of the top wall are indicated by broken lines 151 a and 151 b . Such impact may be produced by falling debris, rolling of the container or pushing of heavy external material or objects against the container. In all cases, the container is not broken, due to its resilience.
Referring to FIGS. 9-11 , they show a container wall 155 a with a pusher 160 carried by the wall and operable by an occupant to create force F usable to displace the container, and possibly free it from jamming in exterior debris, enabling occupant exit via a side door (see FIGS. 12 and 13 ). The pusher may take the form of a threaded shaft 161 , rotatable by handle 164 located in the shelter interior, there being a tongue and groove connection at 163 between the handle and pusher. A threaded socket 161 c carried by the wall 155 a receives the shaft, for rotation. As the shaft advances, it engages a rock or other debris 162 and force is created to further separate the rock and container (see FIG. 10 ). The wall area 155 b around the socket may be reinforced to better sustain side loading. A viewing slit 180 enables occupant viewing of such progression separation, there typically being a thick glass window 166 in the slit. The limited flexibility of the wall 155 a enables angular adjustment of the pusher and socket, for pusher engagement of different portions of the rock, directly benefitting control of freeing of the container.
FIGS. 12-14 show a container sliding door 170 , slidable in a wall 171 of the container, to allow occupant entrance and exit. An auxiliary door 173 has pivoted connection at 174 with door 170 , allowing outward opening of door 173 , for occupant exit and entrance, as for example is enabled despite jamming of sliding door 170 in its wall slit, due to heavy and exterior debris damage to door 170 , or its slide slot 177 . See FIG. 14 , with the door 173 in outward pivoted position. Pivoted connection 174 includes hinge plates 174 a and 174 b/
Referring to FIGS. 15 and 16 , container 200 has side wall 201 , top and bottom walls 202 and 203 , end walls 204 and 205 , and curved, outwardly convex crush resistant corners, as at 206 - 209 . A “hidden” cylinder 210 contains a sliding door made of flexible KEVLAR material which is 5-7 times stronger and lighter than steel, commonly used for helmet, bullet-proof vests in plastic form.
FIG. 16 is like FIG. 15 , but shows the sliding curved shutter door 212 , deployed into closed or closing position, the resiliently flexible walled container 200 having the following features
Material: (High Density Polyethylene) injected with structural foam. Dimension: 56″W 33″H 28″D Curved Sliding Door: Flexible KEVLAR material. Weight: 60 lbs, up.
FIG. 17 is like FIGS. 15 and 16 , but shows provision of auxiliary equipment: panel inner wall panels 220 ; bank night deposit fixture 221 ; lazy susan swivel 222 ; lamp 223 and computer 224 . | An earthquake shelter comprising a container sized for human occupancy, the container having walls and an access opening and a quickly openable and closable primary door to cover and uncover the opening; the container walls and door consisting of high strength panel material, in excess of 10,000 psi load resistance; the container walls including impact shock resisting material that has extensive outwardly presented surface that is outwardly resilient, the wall or walls being flexible; and shock or impact absorbing cushioning means at the container interior, to cushion sudden movement of an occupant relative to the container as the container is suddenly moved by earthquake transmitted force. Tooling enables occupant displacement, from within the container, of debris outside the containers, while viewing such displacement. | 4 |
BACKGROUND OF THE INVENTION
The background of the invention will be set forth in two parts:
1. Field of the Invention
The present invention pertains generally to the field of knitting machines, and more particular to knitting machines with the ability to count the work production.
2. Description of the Prior Art
The prior art known to the applicant is listed by way of illustration, having limitations in separate communications to the U.S. Pat. Office. The present invention exemplifies improvements over the prior art.
More particularly U.S. Pat. No. 3,983,719, disclosing a knitting needle which turns in a circular motion, having reciprocating fingers used to load and unload thread as it turns in its circular path. It is apparent that the circular knitter had no mechanical means by which to count its circular rotations, or stabilize the knitting machine.
SUMMARY OF THE INVENTION
The circular loop loading knitting machine guides yarn at a given tension through needles, forming rows.
This invention accurately, through the incorporation of a swing arm counting device, will count these said rows.
At predetermined intervals, during the production of tubular work, regardless of speed placed upon the hand crank, the cam upon the apron of the needle embodiment, drive drum will cause a switching counter advance arm to pivot upward and downward upon the cam and counter, causing the counter to advance one, through its movements.
A spring present within the counter, placed below the advancement arm, thus returns the swing arm to the apron base as cam passes, preparing both the arm and counter for each additional revolution.
Upon completion of the tubular work, the shaft and zero return washers may be turned to engage small cams within the counter wheels, to reset the device for its next operation.
Additional physical features to the shell make the portable machine a stationary fixture. This is done by the addition of holes in its base.
Through stabilization the tubular knitting can then be made in excessive lengths, with the capability being numbered through the usage of a ratchet type counter.
The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention, both as to its organization and the manner of operation, together with the further objects and advantages thereof, may best be understood reference to the following drawings, taken in connection with the accompanying drawings in which like reference characters refer to the like elements in several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation view of the knitting machine incorporating a counter, of the present invention, to show its external features.
FIG. 2 is an elevation view with parts broken away to show internal construction of a knitting machine incorporating a cam, switch arm and counter device, of the present invention.
FIG. 3A is of the switching arm from the top view.
FIG. 3B is of the switching arm from a side view.
FIG. 4 is an elevation view of the counter advancing device.
FIG. 5 is an elevation view of the counter holder.
FIG. 6 is a top broken view of counter operation using cam, switch arm, and counter.
FIG. 7A is a side view of switch arm on cylindrical drum apron before meeting cam.
FIG. 7B is a side view of switch arm encountering cam.
FIG. 7C is a side view of switch arm gaining its highest peak on cam, shown in FIGS. 2 and 6.
FIG. 8A is a broken view of the case disclosing the counter switch arm, with the counter at a starting position, relative to FIG. 7A.
FIG. 8B is a broken view of case disclosing the counter at the bottom position relative to FIG. 7C.
FIG. 9A discloses the counting wheels with reverse lock, in place, relative to FIGS. 6 and 8A.
FIG. 9B discloses the counting wheels in motion relative to FIGS. 7B and 8B.
FIG. 10A is of the zero advance washer from a flat front view.
FIG. 10B is of the zero advance washer from a side view.
FIG. 11A is of the zero advance cam on the inner portion of the counting wheels from a flat front view.
FIG. 11B is of the zero advance cam of the inner portion of the counting wheels viewed in a side cut away drawing.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings of the counting knitting needle:
FIG. 1 is the Preferred Embodiment shown in an elevation drawing, with handles (10) provided with better finger placement for grasping the machine during usage and movement. The holes (11) at the base of the knitting machine case, make it possible to attach the knitter to a stationary surface for excessive lengths of knitting to be accomplished and counted through the use of counter 12, upon movement of the hand crank.
The internal structure is revealed in FIG. 2, a cut away side view, and FIG. 6, a cut away top view. The switching arm FIG. 3A, top view, and FIG. 3B, a side view, is stabilized in the case by means of a pin placed through hole 452 of the switching arm and inserted into hole 194 of the machine case, allowing the switching arm to be pivotable.
The surfaces 9, 198, 202 of the machine case, in combination with surface 238 of the Needle Drive Drum 227 and surface 570 of the counter advancement arm enclose the switching arm at surface points 459, 460, 463 and 464 causing minimal stress upon the pivot pin.
The theoretical motion of the switching arm during usage is shown in FIG. 7A through 7C upon rotation of the Needle Drive Drum 227. FIG. 7A shows the switching arm with surface 449 upon the needle drive drum apron 233, which would be in the non-counting position. With the counter end 454 of the switching arm being placed upon plate 576 of the advancing device (FIG. 4) shown in FIG. 8A. Wheel locks 559, 561, 563, and 565 (FIG. 6) positions at this stage are shown in FIG. 9A, preventing movement of the counting wheels.
As the rotation of the Needle Drive Drum 227 begins shown FIG. 7B, surfaces 458 and 448, of the switching arm, begin to rise upon cam 235 with a non-jamming effect, due to a slight counter incline of the switching arm.
When surface 449 of the switching arm, reaches the highest point of the cam 236, FIG. 7C, the counter advancing arm moves downward compressing spring 490, FIG. 8B, upon surface 461 of the counter holder (FIG. 5). As this action is taking place, ratchet 503 with wheel advance 537 turn the first wheel 549, 1/10th of a revolution. During this movement wheel lock 565 moves outward, FIG. 9B, until spring 489 returns it to the counting wheel FIG. 9A, at the completion of the 1/10th revolution.
As the Needle Drive Drum 227 turns and the switching arm passes the cam 236, the return spring 490, held in notch 571 of the counter advancing arm, moving the counter advancing arm and switching arm upward, placing end 449 back upon the Needle Drive Drum Apron 233.
During this return motion the wheel locks hold the counting wheels in place, while wheel advance 537 and ratchet 503 move to their original position FIG. 8A.
The repetition of the above motions, are carried out 9 times per wheel, until wheel advance 537 slips into 549A of the counting wheel, thus moving 2 wheels at a time.
Upon completion of a knitted work, the counter may be reset to zero. This is accomplished through the clockwise turning of knob 547 placed on shaft 540, with return washers 550, FIG. 10A, 10B, catching wheel zero cams 549B, FIG. 11A, 11B, releasing wheel locks 559, 561, 563, and 565, turning counter wheels 553, 553, 551, and 549 and resetting a zero count.
The advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiment of the invention and that no limitations are intended to the details of the construction or design herein shown other than as defined in the appended claims, which form part of this disclosure. | A knitting machine with a needle drive drum revolution counter that indicates the number of fabric rows knit. A cam rotates with the needle drive drum pivoting a switching arm that advances the counter. | 3 |
BACKGROUND OF THE INVENTION
The United States Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the U.S. Department of Energy and the University of California, for the operation of Lawrence Livermore National Laboratory.
The invention relates generally to integrated circuit fabrication, and more particularly to the interconnection of chips mounted on a substrate and methods of forming the interconnects.
One problem in manufacturing hybrid wafer scale integration (HWSI) circuits is making interconnections between the various chips after they have been attached to a common substrate. The speed and compactness of modern electronic systems containing many integrated circuit (IC) chips are often compromised by the methods used to package and interconnect these chips. Ideally, chip-to-chip interconnects should have very high density (e.g. at least 1000 connections on a 1-cm square chip) but very low inductance, capacitance, and resistance. Multi-layer ceramic (MLC) interconnection modules, onto which many unpackaged IC chips can be mounted, partly address these needs but are limited and expensive. The manufacturing processes limit the minimum geometry of MLC interconnects to rather coarse dimensions (about 250 μm pitch). Thus, a very large number of metal layers (as many as 33) is required to provide dense interconnect, power distribution and crosstalk isolation. Other difficulties include thermal expansion mismatch (4×10 -6 /°C. difference between Si and alumina), high dielectric constant (about 9.4 for alumina) with consequent low signal propagation speeds, and substantial thermal resistance of the relatively thick ceramic (typically 2 cm 2 -°C./W).
To overcome limitations and expense of MLC technology for high-performance systems, silicon wafers can be used as substrates for thin-film interconnection modules. These silicon PC boards (SiPCBs) can provide very precise, high-density interconnects with a minimal number (3 or 4) of metal levels. With sufficient metallization thickness (about 5 μm), transmission-line quality interconnects are achievable over wafer-scale distances (about 20 cm). SiPCBs have outstanding thermal and mechanical characteristics; compact liquid-cooled versions can dissipate a heat flux of more than 1000 W/cm 2 , and they are virtually immune to thermal stresses, owing to the thermal expansion match between the chips and the board.
In order to physically attach and then electrically connect IC chips to a silicon wafer, three standard techniques have been successfully adapted from ceramic hybrid technology: flip-chip solder-bump reflow, wire bonding, and tape-automated bonding (TAB). All use macroscopic solder joints or welds to make the electrical connections between chip and module, which are ultimately subject to fatigue failures induced by thermal cycling. An interconnect method which provides low inductance, high interconnection density, high reliability and backside bonding (for heat conduction) is desired; however, none of the prior art methods provide a combination of all these characteristics. Flip-chip technology can provide a fairly dense array of low-inductance (<0.1 nH) interconnects, but has poor heat transfer (elaborate measures are required to dissipate even a 20 W/cm 2 heat flux), and requires extra metallization levels for routing to bond pads and for metallurgical reasons. Electrical contact to the back side of the substrate is poor or nonexistent, which is a problem for certain technologies such as power devices or radiation-hardened CMOS. In contrast, wire-bonding and TAB both permit the chip back side to be rigidly attached to a substrate, which enables much better thermal and electrical contact to the interconnection module. However, both have enough inductance (>2 nH for typical 2.5-mm long bonds) to cause problems in ultra-high speed digital or microwave applications, and both are limited in density.
Thus, chip-to-board interconnection technology appears to be a weak point in terms of electrical performance and mechanical reliability of silicon hybrid WSI technology. A thin-film interconnection technique might provide substantially greater interconnect density (e.g., at least a 50 μm pitch and preferably a 25 μm pitch), with excellent electrical properties (impedance-matched transmission lines, if desired), while enhancing the reliability of the connections by replacing the solder/weld joints with standard thin-film contacts.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide a chip interconnect method and structure for electrically connecting one or more chips to an interconnection substrate on which they are mounted.
It is also an object of the invention to provide a chip interconnect method and structure which provides low inductance, high interconnection density and backside bonding.
It is another object of the invention to provide a chip interconnect method and structure which eliminates macroscopic solder joints and welds, in order to enhance reliability.
It is a further object of the invention to provide a chip interconnect method and structure for use in manufacturing hybrid wafer-scale integrated circuits.
It is also an object of the invention to provide a thin film interconnection method and structure between integrated circuit chips.
It is another object of the invention to provide an interconnection density of at least 1000 connections on a 1-cm square chip.
It is a further object of the invention to provide interconnections on a 25 micron pitch.
It is also an object of the invention to minimize the levels of interconnect.
The invention is an interconnection method and structure in which thin film wires are patterned down the bevelled edges of silicon chips using laser etching (pantography) techniques. The technology features very high interconnect densities (e.g., a 25 μm, pitch), excellent electrical properties, very dense packing of chips, and a face up mounting scheme for optimizing heat transfer, electrical contact and mechanical integrity. This approach reaps many of the benefits of wafer scale integration (compactness, reliability, speed and economy) while retaining a hybrid circuit approach for design flexibility and manufacturability.
A substrate wafer (such as silicon) is patterned and etched to leave rectangular "mesas" at the locations where chips are to be bonded, and further processed to form interconnections, to form a silicon PC board. IC chips are then bonded to the mesas by a thin film joint. The edge of the chip is ground away, typically at an angle of 60° from the horizontal (although other angles such as 90°, i.e. vertical, or even greater are also feasible), including a portion of the mesa to expose a thin smooth flush joint at the chip/mesa interface. Alternatively, the chips may be bonded to the substrate without any mesas. Wires are then fabricated down the chip edges by a variety of methods.
The wafer and chips are coated with a SiO 2 layer followed by an amorphous silicon (a-Si) layer. The a-Si is then locally etched by a laser and the etched pattern is transferred to the underlying SiO 2 by an etching process such as reactive ion etching (RIE) to form vias. The a-Si mask is then plasma stripped. The wafer is metallized, e.g. with gold (over a barrier layer), then overcoated with SiO 2 and then a-Si. The a-Si/SiO 2 laminate is then laser etched and reactive ion etched as previously described to generate an inorganic mask for the metallization. The laser beam focus is maintained at all points on the chip edge by translating the objective lens mount along its optic axis under computer control. The SiO 2 pattern is transferred to the gold by ion milling to remove metal and produce wires, completing the chip-to-board interconnect procedure.
As an alternative to ion milling, metal may be electroplated up through a SiO 2 mask which has been etched where wires are desired. The SiO 2 mask exposes areas of a thin underlying metal layer which acts as a nucleation site. The SiO 2 would then be stripped and the initial coating of metal would be stripped to electrically isolate the electroplated wires. This process combines substractive and additive processes.
Yet another alternative is a direct-write all-additive method for forming the wires down the chip edges. Thin metal wires (e.g., tungsten or nickel) are first laser deposited down chip edges to the wafer by direct laser writing in a suitable gaseous environment. Additional metal is then electrolessly plated onto the laser deposited wires to increase wire size and reduce resistance. Such a process might be particularly useful for repairs.
The invention provides a thin-film hybrid interconnect technology with advantageous electrical properties, very high wiring density, excellent backside thermal and electrical contact to the substrate, compactness, and high reliability under thermal and mechanical stresses. The interconnect electrical properties include low capacitance and low inductance. For CMOS circuits, low capacitance interconnects might eliminate the need for large power intensive high current output drivers. For ECL or GaAs circuits low inductance permits propagation of signals with very fast risetimes. For all circuit families, the very high wiring density (greater than 1,000 wires/chip) allows the use of every other wire as a ground or power wire in a coplanar waveguide geometry, providing exceedingly low crosstalk between signal lines, as well as a very low impedance power distribution scheme. High wiring density also makes it feasible to design new IC's with as many inputs and outputs as desired without increasing the number of metallization layers on the IC. Compact, faceup, thin film bonding enables fabrication of large arrays of CCD imagers. The ability to remove high heat fluxes is important for computer applications.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a cross-section of a portion of a hybrid circuit at an intermediate stage of fabrication showing an integrated circuit chip joined to a mesa atop an interconnection substrate and the formation of a bevelled edge on the chip and portion of the mesa by microgrinding.
FIG. 1B illustrates a chip cut at a reentrant angle beyond vertical.
FIGS. 2A,B are cross-sections of a portion of a hybrid circuit at a further stage of fabrication, showing a dielectric layer and metal layer or wire, respectively, formed on the chip and substrate.
FIG. 3 is a flow chart of a subtractive process for forming metal wires down a chip edge for chip-to-wafer interconnect.
FIG. 4 is a flow chart of an additive process for forming metal wires down a chip edge for chip-to-wafer interconnect.
FIGS. 5A-F illustrate the steps of a quasiadditive or subtractive/additive process for forming metal wires down a chip edge for chip-to-wafer interconnect.
FIG. 6 illustrates the shape of wire formed by the process of FIGS. 5A-F using a thin Si/SiO 2 layer.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1A illustrates a portion of a circuit 10 at an intermediate stage of the fabrication procedure. A <100> silicon wafer 12 is patterned and etched, e.g. in KOH, to leave rectangular "mesas" 14 (typically 50 to 75 microns high, with bevelled edges) at the locations where chips are to be bonded, and further processed to form a silicon PC board, e.g. by formation of thin film contacts or interconnects 30. Pre-tested IC chips 16 are then bonded (on their back sides) to the mesas by a thin-film joint 18 which should preferably be free from large (>10 μm) voids at the edge and electrically conductive. The joint should be able to withstand subsequent moderate temperature processes such as plasma enhanced chemical vapor deposition (e.g. T=250° C.). The Au-Si eutectic system (alloy) (T eutectic =363° C.) is a suitable bond metallurgy (it has been widely used in industry as a thick-film die attach). In contrast to industry practice, gold alloy preforms are not used in the invention, as they would produce an excessively thick joint (typically about 25 μm). A joint thickness of approximately 3 μm, or more generally 1-10 μm, is normally produced, about the minimum acceptable for chips which have not been specially lapped to enhance flatness.
A microgrinder (a computer-controlled dicing saw with a bevelled blade) having a cross section 20 as shown is used to bevel the edge 22 of the chip, typically at an angle of 60° from the horizontal; it also removes a portion 24 of the mesa to expose a thin, smooth (<1 μm roughness), flush joint 26 at the chip/mesa interface. If the chip kerf width is too small to permit 60° beveling, then steeper bevel angles such as 75° may be used; even patterning vertical edges has been achieved. For very space-critical applications where no material can be removed from the top of the chip, it is possible to grind the chip at a reentrant angle (beyond vertical), as shown in FIG. 1B. Thin film wires can now be formed from bond pads or electrical contacts 28 on the chip 16 to contacts or interconnects 30 on wafer 12.
As shown in FIG. 2A a dielectric layer (SiO 2 ) 32 is formed on the chip 16 and substrate 12. Vias 34 are formed in dielectric layer 32 at desired locations. e.g. at chip contact 28 and substrate interconnect 30 to allow electrical interconnections. As shown in FIG. 2B, a metal layer or metal wire (Au) 36 is formed on the dielectric layer 32, making electrical contacts through vias 34.
The edge 22 of chip 16 as well as a portion 24 of mesa 14 is ground away, at a suitable angle, so that a flush joint at the chip-substrate bond 18 is produced. Mesas 14 are formed on the substrate 12 to facilitate the formation of this joint. However, in some cases the mesas may be unnecessary and the chips 16 can be mounted directly on the surface of substrate 12. The chip edge and chip substrate bond can then be ground away to produce the desired flush joint. Although the invention is described with reference to silicon chips mounted on a silicon wafer, other materials can be used, e.g. GaAs chips on a germanium substrate.
A subtractive process, illustrated in the flow chart of FIG. 3, forms the metal wires by a series of deposition and etching steps. Typically, vias or holes for the wires to connect to electrical contacts on the chip or wafer are first formed on the wafer and bevelled chips; otherwise the process can start with the metallization step described below. The wafer with bevelled chips is cleaned and overcoated with a dielectric, e.g. approximately 3 μm of SiO 2 , using plasma-enhanced chemical vapor deposition (PECVD). The SiO 2 is coated with an inorganic mask, e.g. amorphous silicon (a-Si) using PECVD. Carbon could also be used as a mask. The a-Si is then locally etched, preferably by a laser, e.g. by irradiating it in a 760-torr chlorine gas ambient with a computer-controlled argon-ion laser beam, acousto-optically scanned at 3 mm/sec and 300 mW power, focused to a 5-micron spot diameter. The etched pattern is transferred to the underlying SiO 2 by a suitable etching process such as reactive-ion etching (RIE), plasma etching or wet chemical etching, forming vias down to all the chip bond pads, to all points on the wafer which electrically connect to the chip bond pads, and to the chip/mesa joint if good electrical contact to the back side of the chip is needed. The a-Si mask is then plasma-stripped.
The wafer is metallized, e.g. with approximately 3 μm of gold (over a barrier or adhesion layer, e.g. Ti:W), then overcoated with PECVD-deposited SiO 2 and then a-Si or C. The a-Si/SiO 2 laminate is then laser etched and reactive-ion-etched or otherwise processed as described above, to generate an inorganic mask for the metallization (to remove all the metal except for the desired wires). The laser beam focus is maintained at all points on the chip edge by translating the objective lens mount along its optic axis, under computer control. The choice of a "subtractive" laser process which etches an a-Si mask, rather than an "additive" process such as pyrolytic nickel or tungsten deposition, is motivated by the relatively slow deposition rates of the additive processes, coupled with their sensitivity to surface conditions (nucleation, thermal conductivity, and reflectivity). The laser beam focus is maintained on the chip edge using a computer controlled objective lens mount. The SiO 2 pattern is transferred to the gold by ion milling or other etching techniques such as electropolishing, removing all metal from undesired areas and leaving the metal wires, completing the chip-to-board interconnect procedure.
In the chip interconnect process a subtractive process as described can be used to fabricate wires on the chips attached to a wafer. However, the subtractive process is a complex process. First, a plurality of layers of different materials are sequentially deposited on the edge of the chip and substrate. To form gold wires, the following sequence of layers is deposited: Ti:W-Au-Ti:W-SiO 2 -Si(amorphous), with Si being the last (top) layer. The thin titanium tungsten layers are used as adhesion layers for the gold. The amorphous silicon layer is used to form a mask for the SiO 2 and the SiO 2 is used to form a mask for the gold. After depositing all the layers, the silicon is laser etched to form a mask. The SiO 2 /Ti:W is then reactive ion etched (RIE) using the silicon as a mask. The gold layer is then ion milled (preferably in O 2 to etch stop at the Ti:W) to form gold wires.
There are a number of problems with the subtractive process. If the chip-to-substrate joint is of poor quality, gold can get trapped in the crevices and not be removed in the ion milling operation, causing short circuits. Furthermore, it is necessary to prevent metal from covering the active areas of the silicon PC board (the transmission lines which connect the chips) since the presence of an upper metal plane would adversely affect the electrical properties (characteristic impedance) of the transmission lines. This would require a shadow mask or a photolithography step. In addition, the process is slow, particularly because of the ion mill step.
The invention includes an additive process, shown in the flow chart of FIG. 4, for fabrication of wires up the edges of chips by laser deposition. Tungsten or nickel wires are laser deposited on the chip edges. This is a direct write process in which the chip surface or wafer is heated by a laser beam while surrounded by a tungsten hexafluoride or nickel carbonyl atmosphere. Once these tungsten or nickel wires have been produced, the wire size can be increased and the resistance reduced to desired levels by plating up metal on the thin wires. The plating process would be electroless, utilizing metals such as gold, silver, copper, or nickel.
Clearly, the additive process is much simpler than the subtractive process. The additive process should have much higher through-put because it eliminates the ion mill step which is often the rate limiting step of the subtractive process There would also be no possibility of radiation damage from ion milling. It would be impossible to have short circuits between neighboring conductors (although open circuits might occur). No shadow mask or photolithography step is required since the metal is placed only where the laser writes it. Finally, it would be possible to write down vertical edges (using an angled objective lens) which is not possible in the subtractive process because the reactive ion etch step (for SiO 2 ) operates at normal incidence to the wafer, and sputter deposition of metals is difficult on vertical surfaces. Thus, the additive process should be much simpler to carry out and may produce a higher yield.
The additive process, while simpler, has certain limitations. The laser deposition processes require highly toxic gases such as Ni(CO) 4 or WF 6 . Moreover the direct writing processes require that the surface be coated with an absorbing layer such as a-Si, and are sensitive to nucleation and adhesion problems. The laser processes are not fast enough, typically less than 10 mm/sec, for many commercial applications. Finally, electroless plating processes are in many situations less desirable than electroplating processes.
Accordingly, the invention also includes a quasi-additive or subtractive/additive process for forming metal lines using laser or other patterning for chip-to-substrate interconnect. According to the invention, the areas where metal is desired are defined by laser or otherwise etching a pattern in a mask layer to expose a metal surface which is then used to nucleate subsequent electroplating or electroless plating to form a metal line of desired size.
An illustrative specific sequence which could be used for chip-to-substrate interconnect is shown in FIGS. 5A-F. In the first step, as shown in FIG. 5A, a series of layers, Cr (or other suitable metal), SiO 2 , a-Si, are sequentially formed on the substrate/chip assembly. Other metals, e.g. Cu, Au, Ti, as well as other dielectric and mask materials could be used. In step two, as shown in FIG. 5B, the a-Si layer is laser etched in a Cl 2 ambient; the laser etch process is a relatively fast process. In the third step, shown in FIG. 5C, the laser etched a-Si layer is used as a mask to wet chemical etch, plasma etch or reactive ion etch (RIE) the SiO 2 layer, using the Cr layer as an etch stop. Thus, a trench is formed down to the Cr layer which corresponds to the desired metal line position. In step four, as shown in FIG. 5D, a metal wire is built up using electroless or electroplating with the exposed Cr at the bottom of the trench serving as a nucleation site. Typically gold or copper lines can be formed. In step five, as shown in FIG. 5E, once the metal wire has been built up to its desired height, the surrounding a-Si and SiO 2 layers are plasma etched away, leaving a metal line standing on the Cr layer. In the sixth and final step, shown in FIG. 5F, the exposed Cr layer surrounding the metal line is etched away leaving a freestanding metal line formed on the substrate.
If the shape of the metal cross-section is important, i.e., the vertical side must be relatively smooth as for long distance transmission line interconnects, the Si/SiO 2 layer must be as thick as the desired line so that the line is conformal, as shown in FIG. 5D. If, however, the shape of the cross-section is unimportant, e.g. short lengths such as up a chip edge, a much thinner Si/SiO 2 layer can be used, and hence faster laser etching, but the line will then have an irregular "mushroom" shape as shown in FIG. 6.
To demonstrate the ability to interconnect functioning IC's using the thin-film hybrid technology of the invention, a series of simple 1-level hybrid circuits were fabricated. Each hybrid circuit contained several 64K (8K×8) static RAM chips with initial dimensions 8.55 mm×9.6 mm×0.4 mm, with edges bevelled at 60° to the horizontal. Laser patterned 3 micron thick gold wires 100 microns wide on 200 micron centers connect all chip bond pads to the silicon substrate where they are routed to form a connector finger pattern for electrical testing. A conventional circuit would normally have several additional levels of thin film interconnect prefabricated in the silicon PC board instead of the single level of wiring used here. Much finer wiring pitches can be produced. A series of wires have been laser patterned on a 25 micron pitch down a 500 micron high die site; these 12 micron wires on 25 micron centers provided 1600 connections around the perimeter of a 1 cm square chip site, exhibiting the very high pinout capability of this interconnect technology.
A series of fully functional 2-chip hybrids were fabricated. The resistance of the interconnects was about 0.1 ohm for the chip to board (bevelled edge) segment. The thin film hybrid circuits exhibited excellent reliability, withstanding the thermal shock of an abrupt plunge into liquid nitrogen. The tensile strengths of the chip/substrate joints were typically measured to be 10 MPa (1500 psi). By attaching the hybrid circuits to a microchannel heat sink, it was possible to thermally cycle the joint 1 million times between room temperature and 110° C.; no degradation of the bond was observed after such stress cycling. Since there are no solder joints, only thin film interconnections, the circuits should have long term reliability.
Changes and modifications in the specifically described embodiments can be carried out without departing from the scope of the invention which is intended to be limited only by the scope of the appended claims. | Integrated circuit chips are electrically connected to a silica wafer interconnection substrate. Thin film wiring is fabricated down bevelled edges of the chips. A subtractive wire fabrication method uses a series of masks and etching steps to form wires in a metal layer. An additive method direct laser writes or deposits very thin metal lines which can then be plated up to form wires. A quasi-additive or subtractive/additive method forms a pattern of trenches to expose a metal surface which can nucleate subsequent electrolytic deposition of wires. Low inductance interconnections on a 25 micron pitch (1600 wires on a 1 cm square chip) can be produced. The thin film hybrid interconnect eliminates solder joints or welds, and minimizes the levels of metallization. Advantages include good electrical properties, very high wiring density, excellent backside contact, compactness, and high thermal and mechanical reliability. | 7 |
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