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This is a 371 of PCT/KR94/00178 filed Dec. 20, 1994, published as WO95/18109 Jul. 6, 1995.
1. Field of the Invention
The present invention relates to novel pyrimidinedione derivatives, which are useful as an antiviral agent, particularly as a treating agent for acquired immunodeficiency syndrome (AIDS), and pharmaceutically acceptable salts thereof. The invention also relates to processes for the preparation of such derivatives and to pharmaceutical compositions containing same as active ingredients.
2. Description of the Prior Art
Various compounds such as AZT (3'-azido-3'-deoxythymidine); DDC (2',3'-dideoxycytidine), DDI (2',3'-dideoxyinosine) and D4T (3'-deoxy-2',3'-didehydrothymidine) have been reported to have the ability, albeit limited, to inhibit the reproduction of AIDS virus; and they are also known to produce undesirable side effects due to their toxicity.
In order to minimize such problems, therefore, many attempts have been made. For example, 2,4-pyrimidinedione derivatives substituted with an alkoxymethylene group on the N-1 position thereof have been published in J. Med. Chem., 35, 4713 (1992); J. Med. Chem., 35, 337 (1992); J. Med. Chem., 34, 1508 (1991); J. Med. Chem., 34, 1394 (1991); J. Med. Chem., 34, 349 (1991); Molecular Pharm., 39, 805 (1991); Molecular Pharm., 44, 694 (1993); EP 0,449,726 A1; EP 0,420,763 A2; and U.S. Pat. No. 5,318,972 and reported to have an improved activity against human immunodeficiency virus (HIV), while exhibiting a lower toxicity. However, needs have continued to exist for effective compounds with excellent potency against HIV with a lower toxicity.
The present inventors have studied for a long time in search for 2,4-pyrimidinedione compounds which have a strong activity against HIV as well as a lower toxicity, and, as a result, have discovered that 2,4-pyrimidinedione compounds with an allyl or propargyl group in the N-1 position of the 2,4-pyrimidinedione ring exhibit strong antiviral activities against HIV.
SUMMARY OF THE INVENTION
Accordingly, it is a primary object of the present invention to provide novel compounds having superior antiviral activities against HIV with reduced toxicity.
It is another object of the present invention to provide pharmaceutical compositions containing same.
It is a further object of the present invention to provide processes for the preparation of said novel compounds.
In accordance with one aspect of the present invention, there are provided novel 2,4-pyrimidinedione compounds of formula(I): ##STR2## wherein: R 1 represents an unsubstituted or substituted allyl group represented by CH 2 CH═CR 5 R 6 or an unsubstituted or substituted propargyl group represented by CH 2 C.tbd.CR 7 wherein R 5 , R 6 and R 7 are each independently a hydrogen atom; a methyl group optionally substituted with a halogen atom, or a C 1-10 carbonyloxy, hydroxy, azido, cyano, optionally substituted amino, optionally substituted phosphonyl, optionally substituted phenyl, C 3-10 heteroaryl, C 1-3 alkoxy or benzyloxy radical; a C 2-10 alkyl or alkenyl group; a cyclopropyl group; an optionally substituted phenyl group; a C 3-10 heteroaryl group; a C 1-10 ester group; or an optionally substituted C 1-10 alkylamide group;
R 2 represents a halogen atom, an optionally substituted C 1-5 alkyl, C 3-6 cycloalkyl, C 2-8 alkenyl or C 2-8 alkynyl group, or a benzyl group;
R 3 and R 4 represent independently a hydrogen or halogen atom, or a hydroxy, C 1-3 alkyl fluoromethyl, C 1-3 alkoxy, amino, C 2-6 alkylester or C 2-7 alkylamide group;
A represents an oxygen or sulfur atom;
Z represents an oxygen or sulfur atom; a carbonyl group; an amino group; or a methylene group optionally substituted with at least one selected from the group consisting of a halogen, and a cyano, hydroxy, azido, amino, C 1-3 alkylamide, C 1-4 ester, and nitro groups.
In accordance with another aspect of the present invention, there are provided pharmaceutically acceptable salts of the compounds of formula(I).
In accordance with a further aspect of the present invention, there are provided pharmaceutical compositions comprising one or more of the 2,4-pyrimidinedione compounds represented by formula(I) and their salts as active ingredients and pharmaceutically acceptable carriers and/or adjuvants.
In accordance with still another aspect of the present invention, there are provided with processes for preparing the 2,4-pyrimidinedione compounds.
DETAILED DESCRIPTION OF THE INVENTION
Among the compounds of the present invention, preferred compounds are those wherein: R 2 is an optionally substituted C 1-5 alkyl group and/or A is an oxygen atom and/or Z is an oxygen or sulfur atom, or a carbonyl or methylene group.
The 2,4-pyrimidinedione compound of formula(I) of the present invention may be prepared by reacting a compound of formula(II) with a compound of formula(III), as shown in Reaction Scheme (1): ##STR3## wherein: A, R 1 , R 2 , R 3 , R 4 and Z have the same meanings as defined above;
X represents a halogen atom or a sulfonyloxy group.
The above reaction may be conducted in the presence of a base and a solvent at a reaction temperature ranging from 0° to 100° C. under a nitrogen blanket and in a molar ratio of the compound (II) and the compound (III) ranging from 1:0.8 to 1:1.2. Representative of the base include anhydrous potassium carbonate, anhydrous sodium carbonate, potassium tert-butoxide and the like. The solvent is preferably polar and representative thereof include dimethylformamide, dimethylsulfoxide, hexamethylphosphoramide and the like.
The compounds(II) used as the starting material in the preparation of the 2,4-pyrimidinedione compounds may be prepared by using the methods as shown in Reaction Scheme (2) depending on the Z group. ##STR4## wherein: R 2 , R 3 and R 4 have the same meanings as defined previously.
In accordance with the method (i), a compound of formula (IV) is reacted using a known method disclosed in, e.g., Ber., 52B, 869 (1919) and J. Med. Chem., 7, 808 (1964) to provide a compound of formula (V) (step (a)), which is hydrolyzed with an acid, e.g., hydrochloric acid, to provide a compound of formula (VI) (step (b)). Thereafter, the compound (VI) is reacted with an arylthio compound, e.g., 3,5-dimethylthiophenol, in an alcoholic solvent, e.g., ethanol, in the presence of a base, e.g., potassium hydroxide, to provide a compound of formula (II-a) (step (c)).
In the method (ii), the compound of formula (V) obtained in step (a) above is reacted with an arylacetonitrile compound, e.g., 3,5-dimethylphenylacetonitrile, and a base, e.g., sodium hydride, in a polar solvent, e.g., dimethylformamide, under a nitrogen blanket to provide a compound of formula (VII) (step (d)), which is hydrolyzed by the method described in the step (b) above to provide a compound of formula (II-b) (step (e)).
Further, in accordance with the method (iii), the compound of formula (VII) obtained in step (d) above is reacted with a base, e.g., sodium hydride, in a polar solvent, e.g., dimethylformamide, under an oxygen containing atmosphere to provide a compound of formula (VIII) (step (f)), which is hydrolyzed by the method described in the step (b) above to provide a compound of formula (II-c) (step (g)).
In accordance with the method (iv), the compound of formula (IV) is reacted with phenol in a polar solvent, e.g., dimethylformamide, in the presence of a base, e.g., sodium hydride, to provide a compound of formula (IX) (step (h)), which is reacted with an organometallic compound, e.g., sodium benzylate in an aprotic solvent, e.g., toluene, to provide a compound of formula (X) (step (i)). Thereafter, the compound (X) is subjected to a hydrogen addition reaction in an alcoholic solvent, e.g., ethanol in the presence of a palladium catalyst, e.g., 10% palladium-on-carbon, to provide a compound of formula (II-d) (step (j)).
The compounds of formula (III) used in the present invention are commercially available.
Exemplary compounds of Formula(I) of the present invention which can be prepared in accordance with the inventive method described are listed below:
1-allyl-5-ethyl-6-phenylthio-2,4-pyrimidinedione; 1-(2-butenyl)-5-ethyl-6-phenylthio-2,4-pyrimidinedione; 1-cinnamyl-5-ethyl-6-phenylthio-2,4-pyrimidinedione; 1-(3-methyl-2-butenyl)-5-ethyl-6-phenylthio-2,4-pyrimidinedione; 1-(4-ethoxy-2-butenyl)-5-ethyl-6-phenylthio-2,4-pyrimidinedione; 1-(4-benyloxy-2-butenyl)-5-ethyl-6-phenylthio-2,4-pyrimidinedione; 1-propargyl-5-ethyl-6-phenylthio-2,4-pyrimidinedione;
1-allyl-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(2-butenyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-cinnamyl-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(methoxycarbonylallyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(carboxyallyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(4-chloro-2-butenyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-propargyl-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(2-butynyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(3-phenyl-2-propynyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(2-pentenyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(4-hydroxy-2-butenyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione;
1-(2-butenyl)-5-isopropyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(2-pentenyl)-5-isopropyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-cinnamyl-5-isopropyl-6-(3, 5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(methoxycarbonylallyl)-5-isopropyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(2-butynyl)-5-isopropyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione; 1-(3-phenyl-2-propynyl)-5-isopropyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione;
1-allyl-5-ethyl-6-benzyl-2,4-pyrimidinedione; 1-(2-butenyl)-5-ethyl-6-benzyl-2,4-pyrimidinedione; 1-cinnamyl-5-ethyl-6-benzyl-2,4-pyrimidinedione;
1-allyl-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione; 1-(2-butenyl)-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione; 1-cinnamyl-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione; 1-(3-methyl-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione; 1-(methoxycarbonylallyl)-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione; 1-propargyl-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione; 1-(2-butynyl)-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione; 1-(3-phenyl-2-propynyl)-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione;
1-(2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione; 1-cinnamyl-5-isopropyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione; 1-(3-phenyl-2-propynyl)-5-isopropyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione;
1-allyl-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(trans-cinnamyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(cis-cinnamyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(2-pentenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(3-methyl-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(methoxycarbonylallyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(ethoxycarbonylallyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(isopropoxycarbonylallyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(4-chloro-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(4-azido-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(4-acetoxy-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(4-hydroxy-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(4-methoxy-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-propargyl-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(2-butynyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(3-phenyl-2-propynyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-cinnamyl-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(2-pentenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(methoxycarbonylallyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(4-chloro-2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(4-azido-2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione;
1-(4-acetoxy-2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(4-hydroxy-2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(2-butynyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione; 1-(3-phenyl-2-propynyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione;
1-allyl-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-(2-butenyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-(trans-cinnamyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-(cis--cinnamyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-(4-hydroxy-2-butenyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-propargyl-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-(3-phenyl-2-propynyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-(2-pentenyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-(methoxycarbonylallyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione;
1-(2-butenyl)-5-isopropyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-cinnamyl-5-isopropyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-(methoxycarbonylallyl)-5-isopropyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; 1-(2-butynyl)-5-isopropyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione; and 1-(3-phenyl-2-propynyl)-5-isopropyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione.
Furthermore, the present invention encompasses, within its scope, those pharmaceutically acceptable salts of the compounds of formula(I). Suitable pharmaceutically acceptable salts of the 2,4-pyrimidinedione compounds(I) may include alkali or alkaline earth metallic salts, e.g., a sodium, potassium, magnesium, calcium salts and the like. Further, in case that any one of R 1 , R 3 and R 4 in formula (I) is an amino group, such inorganic acid salts as a hydrochloride, hydrobromide, sulfate, phosphate, nitrate, perchlorate and the like; and such organic carboxylic and sulfonic acid salts as a formate, acetate, propionate, succinate, glycolate, lactate, fumarate, 4-hydroxybenzoate, methanesulfonate, ethanesulfonate and the like are also included within the scope of the pharmaceutically acceptable salts of the present invention.
As described previously, the 2,4-pyrimidinedione compounds(I) of the present invention and their pharmaceutically acceptable salts possess a strong antiviral activity, particularly against HIV.
The present invention also includes within its scope pharmaceutical compositions comprising one or more of the compounds(I) and their above-mentioned salts as active ingredients, in association with pharmaceutically acceptable carriers, excipients or other additives, if necessary.
The pharmaceutical compositions of the invention may be formulated for administration orally or by injection. The composition for oral administration may take various forms such as tablets and gelatin capsules, which may contain conventional additives such as a diluent (e.g., lactose, dextrose, sucrose, mannitol, sorbitol, cellulose and/or glycine), a lubricant (e.g., silica, talc, stearic acid or its magnesium and calcium salts and polyethylene glycol). In the case of the tablet form, the composition may further comprise a coupling agent (e.g., magnesium aluminum silicate, starch paste, gelatin, tragakans, methyl cellulose, sodium carboxymethyl cellulose and polyvinyl picolidine) and optionally a dusting agent (e.g., starch, agar and alginic acid or its sodium salt), absorbent, colorant, favour, sweetener and the like. The composition for injection may be an isotonic solution or a suspension.
The composition may be sterilized and/or contain an adjuvant such as a preservative, stabilizer, wetting agent, emulsifier, a salt for controlling an osmotic pressure and/or a buffer solution, and other pharmaceutically effective materials.
The pharmaceutical compositions can be prepared by a conventional mixing, granulating or coating method and may comprise preferably about 0.1 to 75%, more preferably about 1 to 50% of an active ingredient. The unit dosage of the composition suitable for the, administration to human of a weight of about 50 to 70 kg may comprise about 10 to 200 mg of the active ingredient.
The following Examples are given for the purpose of illustration only and are not intended to limit the scope of the invention.
In the Examples, unless otherwise specified, the evaporation was conducted under a reduced pressure, preferably under a pressure ranging from about 15 to 100 mmHg, and the flash chromatography was carried out by using Merck Kieselgel 60, 230-400 mesh marketed by Merck.
Preparation 1
Synthesis of 5-ethyl-6-phenylthio-2,4-pyrimidinedione
Step 1) Synthesis of 5-ethyl-6-chloro-2,4-pyrimidinedione
A solution of 32 g (0.16 mol) of 2,4-dimethoxy-5-ethyl-6-chloro-1,3-pyrimidine in 130 ml of conc. HCl was refluxed with stirring. After 4 hours, the reaction mixture was cooled to room temperature to give a light yellow precipitate, which was collected by filtration and recrystallized from dichloromethane-methanol(1:1) to afford 18.4 g (yield 67%) of the title compound as a white solid.
M.p.: 218° to 219° C. 1 H-NMR(300 MHz, CD 3 OD) δ 1.06(3H, t, J=7.5 Hz), 2.45(2H, q, J=7.5 Hz) IR(KBr) 3377(w, N--H), 1730 and 1630 cm -1 (s, CO) m/z(EI) 174(M + , 100%), 159(M--CH 3 + , 94%)
Step 2) Synthesis of 5-ethyl-6-phenylthio-2,4-pyrimidinedione
To a stirred solution of 3.28 g (58.4 mmol) of potassium hydroxide in 120 ml of anhydrous ethanol were added 10.2 g (58.4 mmol) of the compound obtained from step 1 and 7.2 ml (58.4 mmol) of benzenethiol. The resulting mixture was refluxed for 24 hours and evaporated under reduced pressure to give a white precipitate, which was washed with distilled water and recrystallized from ethanol to afford 18.2 g (yield 84%) of the title compound as a white solid.
M.p.: 221° to 223° C. 1 H-NMR(300 MHz, CD 3 OD) δ 1.11(3H, t, J=7.5 Hz), 2.58(2H, q, J=7.5 Hz), 7.49(5H, m) IR(KBr) 3379(w, N--H), 1703 and 1632 cm -1 (s, CO) m/z(EI) 248(M + , 63%), 233(M--CH 3 + , 100%)
Preparation 2
Synthesis of 5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione
To a stirred solution of 2.02 g (36 mmol) of potassium hydroxide dissolved in 100 ml of anhydrous ethanol were added 6.28 g (36 mmol) of the compound obtained from step 1 of Preparation 1 and 5 g (36 mmol) of 3,5-dimethylthiophenol. The resulting mixture was refluxed for 24 hours and evaporated under reduced pressure to give a white precipitate, which was washed with distilled water and recrystallized from ethanol to afford 7.5 g (yield 75%) of the title compound as a white solid.
M.p.: 224° to 225° C. 1 H-NMR(200 MHz, CD 3 OD) δ 1.14(3H, t, J=7.5 Hz), 2.36(6H, s), 2.55 (2H, q, J=7.5 Hz), 7.06(1H, s), 7.16-7.26(3H, m), 9.04(1H, s) m/z(EI) 276(M + , 73%), 261(M--CH 3 + , 100%)
Preparation 3
Synthesis of 5-isopropyl-6-(3,5-dimethylphenylthio-2,4-pyrimidinedione
Step 1) Synthesis of 2,4-dimethoxy-5-isopropyl-6-chloro-1,3-pyrimidine
To 50 ml of anhydrous methanol was added 0.46 g (20 mmol) of sodium to produce sodium methoxide, and then 4.51 g (20 mmol) of 2,4,6-trichloro-5-isopropyl-1,3-pyrimidine was added thereto. The resulting mixture was stirred at room temperature for about 24 hours and evaporated under reduced pressure to give an oily residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:10) as an eluent to afford 4.11 g (yield 95%) of the title compound as a colorless oil.
1 H-NMR(200 MHz, CDCl 3 ) δ 1.23(6H, d, J=7.1 Hz), 3.40(1H, m), 3.94(3H, s), 3.97(3H, s)
Step 2) Synthesis of 5-isopropyl-6-chloro-2,4-pyrimidinedione
A solution of 1.00 g (4.619 mmol) of the compound obtained from step 1 in 20 ml of conc. HCl-methanol (1:3) was refluxed with stirring. After about 4 hours, the reaction mixture was evaporated under reduced pressure to give a white solid, which was further purified by recrystallization from chloroform-methanol to afford 581 mg (yield 67%) of the title compound as a white solid.
M.p.: 250° to 251° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.25(6H, d, J=7.1 Hz), 3.13(1H, m) m/z(EI), 188(M + , 39%), 173(M--CH 3 + , 100%)
Step 3) Synthesis of 5-isopropyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione
To a stirred solution of 2 g (10.6 mmol) of the compound obtained from step 2 in 25 ml of ethanol were added 2.2 g (15.9 mmol) of 3,5-dimethylthiophenol and 654 mg (11.7 mmol) of potassium hydroxide. The resulting mixture was refluxed with stirring for 23 hours and evaporated under reduced pressure to give a white solid, which was washed with distilled water and dried under reduced pressure to afford 2.9 g (yield 94%) of the title compound as a white solid.
M.p.: 225° to 226° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.34(6H, d, J=7.1 Hz), 2.35(6H, s), 3.11(1H, m), 7.14(1H, s), 7.16(2H,s), 9.30(1H,s)
Preparation 4
Synthesis of 5-ethyl-6-benzyl-2,4-pyrimidinedione
Step 1) Synthesis of 2,4-dimethoxy-5-ethyl-6-(α-cyanobenzyl)-1,3-pyrimidine
A solution of 20.25 g (0.1 mol) of 2,4-dimethoxy-5-ethyl-6-chloro-1,3-pyrimidine and 14 g (0.12 mol) of phenylacetonitrile in 60 ml of dimethylformamide (DMF) was cooled to 0° C. under an atmosphere of nitrogen and 4.4 g (0.11 mol) of 60% sodium hydride was added with stirring thereto. The resulting mixture was then stirred at room temperature for 16 hours, neutralized with a dil. HCl, extracted with ether, washed with water, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give an ivory oily residue. The residue was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:1) as an eluent to afford 17.95 g (yield 63%) of the title compound as a white solid.
M.p.: 73° to 74° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.95(3H, t, J=7.5 Hz), 2.47-2.59(2H, m), 3.97(3H, s), 4.00(3H, s), 5.31(1H, s), 7.26-7.47(5H, m)
Step 2) Synthesis of 5-ethyl-6-benzyl-2,4-pyrimidinedione
A solution of 3.95 g (14.0 mmol) of the compound obtained from step 1 in 100 ml of conc. HCl was refluxed with stirring. After about 45 hours, the reaction mixture was cooled to room temperature to give a white precipitate, which was collected by filtration and recrystallized from methanol to afford 2.64 g (yield 82%) of the title compound as a white solid.
M.p.: 240° to 241° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.02(3H, t, J=7.5 Hz), 2.74(2H, q, J=7.5 Hz), 4.15(2H, s), 7.18-7.32(5H, m) m/z(EI) 230(M + , 100%), 215(M--CH 3 + , 38%)
Preparation 5
Synthesis of 5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione
Step 1) Synthesis of 2,4-dimethoxy-5-ethyl-6-(α-cyano-3,5-dimethylbenzyl)-1,3-pyrimidine
A solution of 13.26 g (65.5 mmol) of 2,4-dimethoxy-5-ethyl-6-chloro-1,3-pyrimidine and 11.4 g (78.6 mmol) of 3,5-dimethylphenylacetonitrile in 120 ml of DMF was cooled to 0° C. under nitrogen and 3.14 g (78.6 mmol) of 60% sodium hydride was added portionwise, with stirring, thereto. The resulting mixture was stirred for 14 hours at room temperature, neutralized with acetic acid, and evaporated under reduced pressure to give a brown-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:10) as an eluent to afford 13.2 g (yield 65%) of the title compound as a white solid.
M.p.: 86° to 88° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.96(3H, t, J=7.4 Hz), 2.87(6H, s), 2.46-2.58(2H, m), 3.97(3H, s), 4.01(3H, s), 5.22(1H, s), 6.94(1H, s), 7.02(2H, s)
Step 2) Synthesis of 5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione
A solution of 2 g (6.43 mmol) of the compound obtained from step 1 in 20 ml of conc. HCl was refluxed with stirring in an oil bath. After 72 hours, the reaction mixture was cooled to room temperature and evaporated under reduced pressure to give a light yellow residue, which was recrystallized from chloroform-methanol to afford 1.28 g (yield 77%) of the title compound as a white solid.
M.p.: 228° to 229° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.02(3H, t, J=7.4 Hz), 2.27(6H, s), 2.42(2H, q, J=7.4 Hz), 3.74(2H, s), 6.79(2H, s), 6.95(1H, s), 7.72(1H, s), 8.50(1H, s)
Preparation 6
Synthesis of 5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
Step 1) Synthesis of 2,4-dimethoxy-5-ethyl-6-(3,5-dimethylbenzoyl)-1,3-pyrimidine
To a stirred solution of 2.35 g (7.56 mmol) of the compound obtained from step 1 of Preparation 5 in 50 ml of DMF was added 363 mg (9.07 mmol) of 60% sodium hydride at room temperature under an atmosphere of nitrogen. The resulting mixture was stirred for 4 hours under an air atmosphere, neutralized with acetic acid, and evaporated under reduced pressure to give a light yellow residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:9) as an eluent to afford 1.96 g (yield 86%) of the title compound as a white solid.
M.p.: 97° to 99° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.04(3H, t, J=7.5 Hz), 2.33(6H, s), 2.41(2H, q, J=7.5 Hz), 3.93(3H, s), 4.04(3H, s), 7.22(1H, s), 7.45(2H, s)
Step 2) Synthesis of 5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
A solution of 600 mg (2 mmol) of the compound obtained from step 1 in 15 ml of conc. HCl-methanol (1:2) was refluxed with stirring for about 16 hours and evaporated under reduced pressure to give a light yellow residue, which was recrystallized from methanol-chloroform (5:1) to afford 480 mg (yield 88%) of the title compound as a white solid.
M.p.: 249° to 250° C. 1 H-NMR(200 MHz, CDCl 3 /CD 3 OD) δ 0.97(3H, t, J=7.4 Hz), 2.17(2H, q, J=7.4 Hz), 2.39(6H, s), 7.32(1H, s), 7.50(2H, s) m/z(EI) 272(M + , 42%), 257(M--CH 3 + , 100%)
Preparation 7
Synthesis of 5-isopropyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione
Step 1) Synthesis of 2,4-dimethoxy-5-isopropyl-6-(α-cyano-3,5-dimethylbenzyl)-1,3-pyrimidine
To a stirred solution of 2.9 g (13.4 mmol) of the compound obtained from step 1 of Preparation 3 and 2.32 g (16.1 mmol) of 3,5-dimethylphenylacetonitrile in 26 ml of DMF was added 643 mg (16.1 mmol) of 60% sodium hydride under nitrogen atmosphere. The resulting mixture was stirred for 24 hours at room temperature and neutralized with acetic acid. The mixture was then diluted with ether, washed with water, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:10) as an eluent to afford 2.33 g (yield 54%) of the title compound as a white solid.
M.p.: 107° to 108° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.11(3H, d, J=7.0 Hz), 1.13(3H, d, J=7.0 Hz), 2.29(6H, s), 3.07(1H, m), 4.00(3H, s), 4.04(3H, s), 5.37(1H, s), 6.94(1H, s), 7.00(2H, s)
Step 2) Synthesis of 5-isopropyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione
A solution of 2.14 g (6.58 mmol) of the compound obtained from step 1 in 20 ml of conc. HCl was heated to reflux, with stirring, for 48 hours and evaporated under reduced pressure to give a yellow-colored residue, which was recrystallized from chloroform-methanol (1:6) to afford 1.0 g (yield 56%) of the title compound as a white solid.
M.p.: 268° to 269° C. 1 H-NMR(200 MHz, CDCl 3 /CD 3 OD) δ 1.24(6H, d, J=7.0 Hz), 2.29(6H, s), 2.94(1H, m), 3.73(2H, s), 6.80(2H, s), 6.91(1H, s) m/z(EI) 272(M + , 79%), 257(M--CH 3 + , 100%)
Preparation 8
Synthesis of 5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
Step 1) Synthesis of 2,4-dimethoxy-5-isopropyl-6-(3,5-dimethylbenzoyl)-1,3-pyrimidine
To a stirred solution of 198 mg (0.61 mmol) of the compound obtained from step 1 of Preparation 7 in 6 ml of DMF was added 24 mg (0.63 mmol) of 60% sodium hydride at room temperature under an atmosphere of nitrogen. The resulting mixture was then stirred for about 2 hours under an air atmosphere, diluted with 10 ml of ether, washed with water, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give a light yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:7) as an eluent to afford 190 mg (yield 99%) of the title compound as a white solid.
M.p.: 149° to 150° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.20(6H, d, J=6.9 Hz), 2.37(6H, s), 2.81(1H, m), 3.96(3H, s), 4.08(3H, s), 7.28(1H, s), 7.47(2H, s)
Step 2) Synthesis of 5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
A solution of 186 mg (0.59 mmol) of the compound obtained from step 1 in 15 ml of conc. HCl-methanol (1:2) was heated to reflux with stirring for about 16 hours and evaporated under reduced pressure to give a light yellow-colored residue, which was recrystallized from chloroform-hexane (1:1) to afford 130 mg (yield 77%) of the title compound as a white solid.
M.p.: 238° to 239° C. 1 H-NMR(200 MHz, CDCl 3 /CD 3 OD) δ 1.16(6H, d, J=6.9 Hz), 2.35-2.49 (7H, m), 7.35(1H, s), 7.53(2H, s) m/z(EI) 286(M + , 100%), 271(M--CH 3 + , 32%)
Preparation 9
Synthesis of 5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione
Step 1) Synthesis of 2,4-dichloro-5-ethyl-6-(3,5-dimethylphenoxy)-1,3-pyrimidine
To a stirred solution of 10 g (47.6 mmol) of 5-ethyl-2,4,6-trichloro-1,3-pyrimidine in 150 ml of DMF were added 5.8 g (47.6 mmol) of 3,5-dimethylphenol and 1.9 g (47.6 mmol) of 60% sodium hydride under nitrogen. The resulting mixture was stirred for about 26 hours at room temperature and neutralized with acetic acid. The mixture was then diluted with ether, washed with water, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:30) as an eluent to afford 13 g (yield 92%) of the title compound as a white solid.
M.p.: 91° to 92° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.25(3H, t, J=7.5 Hz), 2.35(6H, s), 2.84(2H, q, J=7.5 Hz), 6.74(2H, s), 6.92(1H, s)
Step 2) Synthesis of 5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione
To a stirred solution of 1.84 g (17 mmol) of benzyl alcohol in 20 ml of toluene was added 0.39 g (17 mmol) of sodium under nitrogen. After stirring for about 6 hours at room temperature, 2.52 g (11.9 mmol) of the compound obtained from step 1 was added and the stirring was continued for another 11 hours at room temperature. The mixture was then evaporated under reduced pressure to give a light yellow residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:9) as an eluent to afford 2.6 g of 2,4-dibenzyloxy-5-ethyl-6-(3,5-dimethylphenoxy)-1,3-pyrimidine as a colorless oil.
A solution of 2 g (4.5 mmol) of the benzylated compound in 20 ml of ethanol was stirred under an atmosphere of hydrogen in the presence of 10% palladium on charcoal at room temperature for 6 hours. The reaction mixture was filtered through Cellite pad and evaporated under reduced pressure to give a light yellow residue, which was recrystallized from methanol-chloroform to afford 420 mg (yield 36%) of the title compound as a white solid.
M.p.: 221° to 222° C. 1 H-NMR(200 MHz, CD 3 OD) δ 0.90(3H, t, J=7.4 Hz), 2.17-2.25(8H, m), 6.62(2H, s), 6.78(1H, s) m/z(EI) 260(M + , 69%), 245(M--CH 3 + , 100%)
Preparation 10
Synthesis of 5-isopropyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione
Step 1) Synthesis of 2,4-dichloro-5-isopropyl-6-(3,5-dimethylphenoxy)-1,3-pyrimidine
To a stirred solution of 2.26 g (10 mmol) of 5-isopropyl-2,4,6-trichloro-1,3-pyrimidine in 150 ml of DMF were added 1.28 g (10.5 mmol) of 3,5-dimethylphenol and 420 mg (10.5 mmol) of 60% sodium hydride under nitrogen. The reaction mixture was stirred for about 17 hours at room temperature and neutralized with acetic acid. The mixture was diluted with ether, washed with water, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give a light yellow-colored oil, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:30) as an eluent to afford 3 g (yield 96%) of the title compound as a white solid.
M.p.: 91° to 92° C. 1 H-NMR(20 MHz, CDCl 3 ) δ 1.39(6H, d, J=7.1 Hz), 2.33(6H, s), 3.56(1H, m), 6.70(2H, s), 6.89(1H, s)
Step 2) Synthesis of 5-isopropyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione
To a stirred solution of 2.2 g (20 mmol) of benzyl alcohol in 20 ml of toluene was added 513 mg (22 mmol) of sodium under nitrogen. After stirring for about 5 hours at room temperature, 3 g (9.7 mmol) of the compound obtained from step 1 was added and the stirring was continued for another 10 hours at room temperature. The mixture was then evaporated under reduced pressure to give a light yellow residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:9) as an eluent to afford 3 g of 2,4-dibenzyloxy-5-isopropyl-6-(3,5-dimethylphenoxy)-1,3-pyrimidine as a colorless oil.
A solution of 2.8 g (6.17 mmol) of the benzylated compound in 20 ml of ethanol was stirred under an atmosphere of hydrogen in the presence of 10% palladium on charcoal at room temperature for 5 hours. The reaction mixture was filtered through Cellite pad and evaporated under reduced pressure to give a light yellow residue, which was recrystallized from methanol-chloroform to afford 1.06 g (yield 63%) of the title compound as a white solid.
M.p.: 229° to 230° C. 1 H-NMR(200 MHz, CD 3 OD) δ 1.20(6H, d, J=7.1 Hz), 2.33(6H, s), 3.35(1H, m), 6.64(2H, s), 6.83(1H, s)
EXAMPLE 1
Synthesis of 1-propargyl-5-ethyl-6-phenylthio-2,4-pyrimidinedione
To a stirred solution of 248 mg (1 mmol) of the compound obtained from Preparation 1 and 138 mg (1 mmol) of anhydrous potassium carbonate in 5 ml of DMF was added 130 μl (1.2 mmol) of propargyl bromide. The reation mixture was stirred for about 24 hours at room temperature and evaporated under reduced pressure to give a yellow residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 120 mg (yield 42%) of the title compound as a white solid.
M.p.: 132° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.10(3H, t, J=7.5 Hz), 2.21(1H, t, J=2.4 Hz), 2.27(2H, q, J=7.5 Hz), 4.82(2H, d, J=2.4 Hz), 7.25-7.43(5H, m), 9.49(1H, s) IR(KBr) 3200(w, NH), 1700, 1650 cm -1 (s, CO)
EXAMPLE 2
Synthesis of 1-(trans-2-pentenyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione
To a stirred solution of 166 mg (0.6 mmol) of the compound obtained from Preparation 2 and 83 mg (0.6 mmol) of anhydrous potassium carbonate in 5 ml of DMF was added 89 μl (0.6 mmol) of 1-bromo-2-pentene. The reaction mixture was stirred at room temperature for about 24 hours and then evaporated under reduced pressure to give a yellow residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 178 mg (yield 86%) of the title compound as a white solid.
M.p.: 129° to 130° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.91(3H, t, J=7.5 Hz), 1.04(3H, t, J=7.5 Hz), 1.94(2H, q, J=7.5 Hz), 2.28(6H, s), 2.70(2H, q, J=7.5 Hz), 4.54-4.59(2H, m), 5.31-5.68(2H, m), 6.76(2H, s), 6.87(1H, s), 8.90(1H, s)
EXAMPLE 3
Synthesis of 1-(3-phenyl-2-propynyl)-5-isopropyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione
To a stirred solution of 203 mg (0.7 mmol) of the compound obtained from Preparation 3 in 5 ml of DMF were added 110 mg (0.8 mmol) of anhydrous potassium carbonate, 116 mg (0.8 mmol) of 1-chloro-3-phenyl-2-propyn, and 471 mg (0.35 mmol) of lithium iodide. The reaction mixture was stirred for about 16 hours at room temperature and evaporated under reduced pressure to give a light yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:3) as an eluent to afford 156 mg (yield 55%) of the title compound as a white solid.
M.p.: 113° to 115° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.22(6H, d, J=7.0 Hz), 2.22(6H, s), 3.50 (1H, m), 5.06(2H, s), 6.82(1H, s), 6.86(2H, s); 7.19-7.31(5H, m), 8.77(1H, s)
EXAMPLE 4
Synthesis of 1-allyl-5-ethyl-6-benzyl-2,4-pyrimidinedione
To a stirred solution of 460 mg (2 mmol) of the compound obtained from Preparation 4 and 276 mg (2 mmol) of anhydrous potassium carbonate in 10 ml of DMF was added 174 μl (2 mmol) of allyl bromide at room temperature. After 48 hours, the mixture was evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (2:5) as an eluent to afford 35 mg (yield 6%) of the title compound as a white solid.
M.p.: 164° to 165° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.06(3H, t, J=7.5 Hz), 2.48(2H, q, J=7.5 Hz), 3.99(2H, s), 4.28-4.31(2H, m), 5.04-5.24(2H, m), 5.85(1H, m), 7.09-7.41(5H, m), 9.37(1H, s)
EXAMPLE 5
Synthesis of 1-(trans-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione
To a stirred solution of 258 mg (1 mmol) of the compound obtained from Preparation 5 in 5 ml of DMF were added 138 mg (1 mmol) of anhydrous potassium carbonate and 121 μl (1 mmol) of 85% trans-crotyl bromide at room temperature. After 45 hours, the reaction mixture was then evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:1) as an eluent to afford 43 mg (yield 14%) of the title compound as a white solid.
M.p.: 145° to 146° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.06(3H, t, J=7.5 Hz), 1.70(3H, d, J=5.1 Hz), 2.30(6H, s), 2.46(2H, q, J=7.5 Hz), 3.92(6H, s), 4.20-4.23 (2H, m), 5.48-5.62(2H, m), 6.69(2H, s), 6.91(1H, s), 9.23(1H, s)
EXAMPLE 6
Synthesis of 1-(trans-cinnamyl)-5-isopropyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione
To a stirred solution of 408 mg (1.5 mmol) of the compound obtained from Preparation 7 in 5 ml of DMF were added 248 mg (1.8 mmol) of anhydrous potassium carbonate and 296 mg (1.5 mmol) of cinnamyl bromide at room temperature. After 36 hours, the reaction mixture was then evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 88 mg (yield 15%) of the title compound as a white solid.
M.p.: 180° to 181° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.31(6H, d, J=7.0 Hz), 2.31(6H, s), 2.85 (1H, m), 3.99(2H, s), 4.47(2H, d, J=4.4 Hz), 6.17(1H, m), 6.40 (1H, d, J=16.1 Hz), 6.73(2H, s), 6.93(1H, s), 7.22-7.40(5H, m), 8.79(1H, s)
EXAMPLE 7
Synthesis of 1-(3-methyl-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a stirred solution of 272 mg (1 mmol) of the compound obtained from Preparation 6 in 5 ml of DMF were added 138 mg (1 mmol) of anhydrous potassium carbonate and 115 μl (1 mmol) of 1-bromo-3-methyl-2-butene at room temperature. After 16 hours; the reaction mixture was evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 248 mg (yield 72%) of the title compound as a white solid.
M.p.: 255° to 260° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.96(3H, t, J=7.4 Hz), 1.37(3H, s), 1.46 (3H, s), 2.03(1H,m), 2.26(1H,m), 2.40(6H, s), 4.23-4.27(2H, m), 4.99(1H, m), 7.33(1H, s), 7.52(2H, s), 8.71(1H, s)
EXAMPLE 8
Synthesis of 1-(methoxycarbonylallyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a stirred solution of 272 mg (1 mmol) of the compound obtained from Preparation 6 and 138 mg (1 mmol) of anhydrous potassium carbonate in 5 ml of DMF was added 138 μl (1 mmol) of 85% methyl 4-bromocrotonate at room temperature. After 4 hours, the reaction mixture was evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (3:1) as an eluent to afford 151 mg (yield 41%) of the title compound as a white solid.
M.p.: 201° to 202° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.96(3H, t, J=7.4 Hz), 2.00-2.31(2H, m), 2.37(6H, s), 3.67(3H, s), 4.22-4.38(2H, m), 5.69(1H, m), 6.67 (1H, m), 7.32(1H, s), 7.49(2H, s)
EXAMPLE 9
Synthesis of 1-(4-chloro-trans-2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a stirred solution of 1.43 g (5 mmol) of the compound obtained from Preparation 8 in 10 ml of DMF were added 690 mg (5 mmol) of anhydrous potassium carbonate and 525 μl (5 mmol) of 1,4-dichloro-trans-2-butene at room temperature. After 42 hours, the reaction mixture was diluted with ether, washed with water, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 860 mg (yield 46%) of the title compound as a white solid.
M.p.: 178° to 179° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.12(3H, d, J=6.9 Hz), 1.20(3H, d, J=6.9 Hz), 2.31(1H, m), 2.39(6H, s), 3.83(2H, d, J=6.5 Hz), 4.08(1H, m), 4.25(1H, m), 5.46-5.72(2H, m), 7.33(1H, s), 7.51(2H, s), 9.41(1H, s)
EXAMPLE 10
Synthesis of 1-(trans-2-butenyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione
To a stirred solution of 260 mg (1 mmol) of the compound obtained from Preparation 9 in 5 ml of DMF were added 138 mg (1 mmol) of anhydrous potassium carbonate and 121 μl (1 mmol) of 85% trans-crotyl bromide at room temperature. After 16 hours, the reaction mixture was evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 188 mg (yield 60%) of the title compound as a white solid.
M.p.: 149° to 150° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.94(3H, t, J=7.5 Hz), 1.61(2H, d, J=6.0 Hz), 2.14-2.30(8H, m), 4.23-4.26(2H, m), 5.40-5.60(2H, m), 6.53(2H, s), 6.77(1H, s), 8.88 (1H, s)
EXAMPLE 11
Synthesis of 1-(2-butynyl)-5-isopropyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione
To a stirred solution of 274 mg (1 mmol) of the compound obtained from Preparation 10 in 5 ml of DMF were added 152 mg (1.1 mmol) of anhydrous potassium carbonate and 163 mg (1.1 mmol) of 1-methylsulfonyl-2-butyn at room temperature. After 15 hours, the reaction mixture was diluted with ether, washed with water, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:4) as an eluent to afford 175 mg (yield 54%) of the title compound as a white solid.
M.p.: 158° to 160° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.15(6H, d, J=7.1 Hz), 1.69(3H, t, J=2.2 Hz), 2.32(6H, s), 2.80(1H, m), 3.73(3H, s), 4.43(2H, q, J=2.2 Hz), 6.60(2H, s), 6.78(1H, s), 8.55(1H, s)
Similarly to Examples above, various 2,4-pyrimidinedione derivatives of the present invention were prepared and a list of them is represented in Table 1.
TABLE 1__________________________________________________________________________Ex. No. R.sup.1 R.sup.2 R.sup.3 R.sup.4 Z .sup.1 H-NMR(200MHz, CDCl.sub.3)δ M.P. (°C.)__________________________________________________________________________12 CH.sub.2 ═CH--CH.sub.2 -- CH.sub.3 CH.sub.2 -- H H S 1.02(3H, t, J=7.5Hz), 2.70 133-134 (2H, q, J=7.5Hz), 4.58- 4.62(2H, m), 5.03-5.15(2H, m), 7.14-7.38 (5H, m), 9,49(1H, s)13 trans CH.sub.3 CH.sub.2 -- H H S 1.01(3H, t, J=7.4Hz), 1.57 132-133 CH.sub.3 CH═CH--CH.sub.2 -- (3H, dd, J=1.2Hz, 6.2Hz), 2.68(2H, q, J=7.4Hz), 4.50- 4.59(2H, m), 5.25-5.65 (2H, m), 7.10-7.36(5H, m), 9.28(1H, s)14 trans PhCH═CH-- CH.sub.3 CH.sub.2 -- H H S 1.04(3H, t, J=7.5Hz), 2.72 180-181 CH.sub.2 -- (3H, q, J=7.5Hz), 4.74- 4.77(2H, m), 5.91-6.11 (2H, m), 6.46(1H, d, J=15.9Hz), 7.15-7.38(10H, m), 9.37(1H, s)15 (CH.sub.3).sub.2 C═CH--CH.sub.2 -- CH.sub.3 CH.sub.2 -- H H S 1.04(3H, t, J=7.4Hz), 1.61 162-163 (3H, s), 1.67(3H, s), 2.70 (2H, q, J=7.4Hz), 4.56- 4.59(2H, m), 4.98-5.05(1H, m), 7.13-7.38(5H, m), 9.24 (1H, s)16 cis CH.sub.3 CH.sub.2 -- H H S 1.02(3H, t, J=7.4Hz), 1.16 103-104 CH.sub.3 CH.sub.2 OCH.sub.2 CH═CH (3H, t, J=7.0Hz), 2.69(2H, --CH.sub.2 -- q, J=7.4Hz), 3.45(2H, q, J=7.0Hz), 4.05(2H, dd, J= 1.4Hz, 6.2 Hz), 4.62(2H, m), 5.35(1H, m), 5.64(1H, m), 7.13-7.38(5H, m), 8.89(1H, s)17 cis CH.sub.3 CH.sub.2 -- H H S 1.03(3H, s, J=7.5Hz), 2.69 105-106 PhCH.sub.2 OCH.sub.2 CH═CH-- (2H, q, J=7.5Hz), 4.13(1H, CH.sub.2 -- m), 4.49 (2H, s), 4.61(2H, m), 5.40(1H, m), 5.67(1H, m), 7.08-7.36(10H, m), 8.98(1H, s)18 CH.sub.2 ═CH--CH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 S 1.04(3H, t, J=7.5Hz), 2.28 164-165 (6H, s), 2.70(2H, q, J= 7.5Hz), 4.58-4.61(2H, m), 5.03-5.17(2H, m), 5.75(1H, m), 6.75(2H, s), 6.87(1H, s), 9.40(1H, s)19 trans CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 S 1.04(3H, t, J=7.5Hz), 1.62 158-159 CH.sub.3 CH═CH--CH.sub.2 -- (3H, dd, J=1.3Hz, 6,2Hz), 2.29(6H, s), 2,70(2H, q, J=7.5Hz), 4.52-4.55(2H, m), 5.37-5.66(2H, m), 6.76 (2H, s), 6.88(1H, s), 9.08 (1H, s)20 trans PhCH═CH-- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 S 1.03(3H, t, J=7.4Hz), 2.23 160-162 CH.sub.2 -- (6H, s), 2.70(2H, q, J=7.5 Hz), 4.73-4.76 (2H, m), 6.04-6.10(1H, m), 6.42(1H, d, J=15.8 Hz), 6.78(2H, s), 6.82 (1H, s), 7.22(5H, m), 9.11(1H, s)21 trans CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 S 1.06(3H, t, J=7.3Hz), 2.26 210-211 CH.sub.3 O.sub.2 CCH═CH-- (6H, s), 2.70(2H, q, J=7.3 CH.sub.2 -- Hz), 3.68(3H, s), 4.73(2H, dd, J=1.7 Hz, 5.0Hz), 5.62 (1H, m), 6.67(1H, m), 6.75 (2H, s), 6.85(1H, s), 9.07 (1H, s)22 trans CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 S 1.04(3H, t, J=7.3Hz), 2.27 164 ClCH.sub.2 CH═CH--CH.sub.2 -- (6H, s), 2.70(2H, q, J=7.3 Hz), 3.91-3.93(2H, m), 4.58-4.60(2H, m), 5.64- 5.69(2H, m), 6.75(2H, m), 6.87(1H, s), 8.86(1H, s)23 cis CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 S 1.08(3H, t, J=7.4Hz), 2.28 152-153 ClCH.sub.2 CH═CH--CH.sub.2 -- (6H, s), 2,71(2H, q, J=7.4 Hz), 4.15(2H, d, J=7.3Hz), 4.64(2H, d, J=7.3Hz), 5.42 (1H, m), 5.71(1H, m), 6.75 (2H, s), 6.88(1H, s), 9.82 (1H, s)24 HC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 S 1.06(3H, t, J=7.5Hz), 2.20 180-181 (1H, t, J=2.4Hz), 2.29(6H, s), 2.73(2H, q, J=7.5Hz), 4.76(2H, d, J=2.4Hz), 6.82 (2H, s), 6.90(1H, s), 9.44 (1H, s)25 H.sub.3 CC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 S 1.03(3H, t, J=7.5Hz), 1.69 186-187 (3H, t, J=2.4Hz), 2.27(6H, s), 2.70(2H, q, J=7.5Hz), 4.70-4.72 (2H, m), 6.81 (2H, s), 6.86(1H, s), 9.74 (1H, s)26 PhC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 S 1.03(3H, t, J=7.4Hz), 2.22 178-180 (6H, s), 2.70(2H, q, J=7.4 Hz), 5.00(2H, s), 6.82- 7.33(8H, m), 8.95(1H, s)27 trans (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 S 1.22(6H, d, J=7.0Hz), 1.61- 166-167 CH.sub.3 CH═CH--CH.sub.2 -- 1.67(3H, m), 2.26 (6H, s), 3.50(1H, m), 3.58-4.60 (2H, m), 5.40-5.67(2H, m), 6.76(2H, s), 6.87(1H, s)28 trans (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 S 0.89(3H, t, J=7.5Hz), 1.21 122--123 CH.sub.3 CH.sub.2 CH=CH-- (6H, d, J=7.0Hz),1.87-2.02 CH.sub.2 -- (2H, m), 2.25 (6H, s), 3.47(1H, m), 4.61(2H, d, J=5.2Hz), 5.40(1H, m), 5.64(1H, m), 6.74(2H, s), 6.84 (1H, s), 10.14(1H, s)29 trans PhCH═CH-- (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 S 1.23(6H, d, J=6.7Hz), 2.23 133-134 CH.sub.2 -- (6H, s), 3.52(1H, m), 4.80- 4.83(2H, m), 6.09(1H, m), 6.46(1H, d, J=15.9Hz), 6.79(2H, s), 6.83(1H, s), 7.17-7.25(5H, m)30 trans (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 S 1.29(6H, d, J=7.0Hz), 2.29 147-148 CH.sub.3 O.sub.2 CCH═CH-- (6H, s), 3.56(1H, m), 3.71 CH.sub.2 -- (3H, s), 4.78-4.82(2H, m), 5.68(1H, m), 6.83-6.87 (4H, m)31 H.sub.3 CC.tbd.CCH.sub.2 -- (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 S 1.24(6H, d, J=7.0Hz), 1.72 165-166 (3H, t, J=2.3Hz), 2.30(6H, s), 3.51(1H, m), 4.78-4.81 (2H, m), 6.85 (2H, s), 6.89(1H, s), 8.87(1H, s)32 trans CH.sub.3 CH.sub.2 -- H H CH.sub.2 1.06(3H, t, J=7.4Hz), 1.69 132-133 CH.sub.3 CH═CH--CH.sub.2 -- (3H, d, J=4.8Hz), 2.47(2H, q, J=7.4Hz), 4.01(2H, s), 4.21-4.23(2H, m), 5.47- 5.54(2H, m), 7.10-7.40(5H, m), 9.10(1H, s)33 trans PhCH═CH-- CH.sub.3 CH.sub.2 -- H H CH.sub.2 1.05(3H, t, J=7.4Hz), 2.48 159-160 CH.sub.2 -- (2H, q, J=7.4Hz), 4.03(2H, s), 4.42-4.45(2H, m), 6.12 (1H, m), 6.38(1H, d, J= 15.1Hz), 7.12-7.44(10H, m), 9.38(1H, s)34 CH.sub.2 ═CH--CH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 CH.sub.2 1.09(3H, t, J=7.5Hz), 2.28 129-130 (6H, s), 2.51(2H, q, J=7.5 Hz), 3.71 (2H, s), 4.49 (2H, dd, J=1.3Hz, 5.8 Hz), 5.12-5.27(2H, m), 5.85(1H, m), 6.80 (2H, s), 6.92(1H, s), 8.55(1H, s)35 trans PhCH═CH-- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 CH.sub.2 1.07(3H, t, J=7.4Hz), 2.31 223-224 CH.sub.2 -- (6H, s), 2.48(2H, q, J=7.4 Hz), 3.97 (2H, s), 4.44- 4.47(2H, m), 6.09-6.43(2H, m), 6.73(2H, s), 6.93 (1H, s), 7.25-7.34(5H, m), 8.26 (1H, s)36 (CH.sub.3).sub.2 C═CH--CH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 CH.sub.2 1.07(3H, t, J=7.5Hz), 1.64 169-170 (3H, s), 1.72(3H, s), 2.30 (6H, s), 2.46 (2H, q, J= 7.5Hz), 3.91 (2H, s), 4.28 (2H, d, J=6.2Hz), 5.08 (1H, m), 6.70(2H, s), 6.92 (1H, s), 9.46(1H, s)37 trans CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 CH.sub.2 1.11(3H, t, J=7.5Hz), 2.30 105-106 CH.sub.3 O.sub.2 CCH═CH-- (6H, s), 2.52(2H, q, J=7.5 CH.sub.2 -- Hz), 3.71(3H, s), 3.73(2H, s), 4.63-4.67(2H, m), 5.89 (1H, m), 6.81-6.95(4H, m), 8.13(1H, s)38 HC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 CH.sub.2 1.07(3H, t, J=7.5Hz), 2.28 163-164 (6H, s), 2.34(1H, t, J=2.4 Hz), 2.48(2H, q, J=7.5Hz), 4.08(2H, s), 4.42(2H, d, J=2.4 Hz), 6.70(2H, s), 6.90(1H, s), 9.03(1H, s)39 H.sub.3 CC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 CH.sub.2 1.08(3H, t, J=7.5Hz), 1.82 179-180 (3H, t, J=2.3Hz), 2.39(6H, s), 2.45(2H, q, J=7.5Hz), 4.09(2H, s), 4.38(2H, d, J=8.4 Hz), 6.72(2H, s), 6.90 (1H, s), 9.40(1H, s)40 PhC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 CH.sub.2 1.09(3H, t, J=7.5Hz), 2.29 187-189 (6H, s), 2.50(2H, q, J= 7.5Hz), 4.16(2H, s), 4.67 (2H, s), 6.75 (2H, s), 6.91(1H, s), 7.01-7.60(5H, m), 9.51 (1H, s)41 trans (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 CH.sub.2 1.28(6H, d, J=7.0Hz), 1.70 187-188 CH.sub.3 CH═CH--CH.sub.2 -- (3H, d, J=4.8Hz), 2.29 (6H, s), 2.83(1H, m), 3.92(2H, s), 4.22 (2H, s), 5.48-5.56(2H, m), 6.69(2H, s), 6.91 (1H, s), 8.77(1H, s)42 PhC.tbd.CCH.sub.2 -- (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 CH.sub.2 1.32(6H, d, J=7.0Hz), 2.31 149-150 (6H, s), 2.89(1H, m), 4.20 (2H, s), 4.69(2H, s), 6.77(2H, s), 6.93(1H, s), 7.27-7.48 (5H, m)43 CH.sub.2 ═CH--CH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.97(3H, t, J=7.4Hz), 2.07 177-178 ∥ (1H, m), 2.29(1H, m), C 2.39(6H, s), 3.98 (1H, m), 4.37(1H, m), 4.98-5.13(2H, m), 5.69 (1H, m), 7.34(1H, s), 7.52(2H, s), 9.42(1H, s)44 trans CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.98(3H, t, J=7.4Hz), 1.51 151-152 CH.sub.3 CH═CH--CH.sub.2 -- ∥ (3H, d, J=4.8Hz), 1.97- C 2.36(2H, m), 2.42(6H, s), 4.03-4.25(2H, m), 5.35- 5.49(2H, m), 7.34(1H, s), 7.53(2H, s), 9.69(1H, s)45 trans PhCH═CH-- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.95(3H, t, J=7.4Hz), 1.97- 171-172 CH.sub.2 -- ∥ 2.27(8H, m), 4.21-4.47 C (2H, m), 5.97(1H, m), 6.16 (1H, d, J=16.0Hz), 7.07- 7.49(8H, m), 8.99(1H, s)46 trans CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.80(3H, t, J=7.5Hz), 0.95 163-164 CH.sub.3 CH.sub.2 CH═CH-- ∥ (3H, t, J=7.5Hz),1.84(2H, CH.sub.2 -- C q, J=7.5Hz), 2.04(1H, m), 2.29(1H, m), 2.39(6H, s), 4.14 (2H, m), 5.24-5.49 (2H, m), 7.32(1H, s), 7.50 (2H, s), 9.14(1H, s)47 trans CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.95(3H, t, J=7.5Hz), 2.04 158-159 ClCH.sub.2 CH═CH--CH.sub.2 -- ∥ (1H, m), 2.30(1H, m), 2.39 C (6H, s), 3.84 (2H, d, J= 5.3Hz), 4.15 (2H, m), 5.60 (2H, m), 7.33(1H, s), 7.50 (2H, s), 9.03(1H, s)48 HC.tbd.CCH.sub.2 -- CH.sub.3 CH-- CH.sub.3 CH.sub.3 O 0.96(3H, t, J=7.4Hz), 2.03- 214-215 ∥ 2.34(3H, m), 2.40 (6H, s), C 4.36-4.45(2H, m), 7.35(1H, s), 7.60(2H, s), 9.19(1H, s)49 H.sub.3 CC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.92(3H, t, J=7.3Hz), 1.44 202-203 ∥ (3H, t, J=2.3Hz), 1.96- C 2.28(2H, m), 2.37 (6H, s), 4.12(1H, m), 4.59(1H, m), 7.29(1H, s), 7.58(2H, s), 9.85 (1H, s)50 PhC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.95(3H, t, J=7.4Hz), 2.06- 194-195 ∥ 2.25(8H, m), 4.40 (1H, d, C J=17.9Hz), 5.09 (1H, d, J= 17.9Hz), 6.98-7.30(6H, m), 7.61(2H, s), 9.42(1H, s)51 trans (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 1.14(3H, d, J=6.8Hz), 1.23 195-196 CH.sub.3 CH═CH--CH.sub.2 -- ∥ (3H, d, J=6.8Hz), 1.50 C (3H, d, J=4.9Hz), 2.27- 2.42(7H, m), 3.99-4.24 (2H, m), 5.25-5.47(2H, m), 7.35(1H, s), 7.55(2H, s), 8.96(1H, s)52 trans PhCH═CH-- (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 1.14(3H, d, J=6.8Hz), 2.24 187-189 CH.sub.2 -- ∥ (3H, d, J=6.8Hz), 2.29- C 2.39(7H, m), 4.28-4.51 (2H, m), 5.98(1H, m), 6.16 (1H, d, J=16.0Hz), 7.08- 7.27(6H, m), 7.53 (2H, s), 9.74(1H, s)53 trans (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 0.78(3H, t, J=7.5Hz), 1.11 168-169 CH.sub.3 CH.sub.2 CH═CH-- ∥ (3H, d, J=6.8Hz), 1.20(3H, CH.sub.2 -- C d, J=6.8Hz), 1.73-1.88(2H, m), 2.30 (1H, m), 2.38(6H, s), 4.11(2H, d, J=6.2Hz), 5.20-5.43(2H, m), 7.31 (1H, s), 7.51(2H, s), 8.59 (1H, s)54 trans (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 1.15(3H, d, J=6.9Hz), 1.22 188-189 CH.sub.3 O.sub.2 CCH═CH-- ∥ (3H, d, J=6.9Hz), 2.28- CH.sub.2 -- C 2.39(7H, m), 3.68 (3H, s), 4.11-4.45(2H, m), 5.70(1H, m), 6.66 (1H, m), 7.50(1H, s), 7.52(2H, s), 8.65(1H, s)55 H.sub.3 CC.tbd.CCH.sub.2 -- (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 1.11(3H, d, J=6.8Hz), 1.19 191-192 ∥ (3H, d, J=6.8Hz), 1.45(3H, C t, J=2.4Hz), 2.26-2.40 (7H, m), 4.15(1H, m), 4.61 (1H, m), 7.31(1H, s), 7.61 (2H, s), 8.82 (1H, s)56 PhC.tbd.CCH.sub.2 -- (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 1.11(3H, d, J=6.8Hz), 1.20 183-185 ∥ (3H, d, J=6.8Hz), 2.25- C 2.37(7H, m), 4.36 (1H, d, J=17.9Hz), 5.05 (1H, d, J= 17.9Hz), 6.95-7.28(6H, m), 7.62 (2H, s), 8.75(1H, s)57 CH.sub.2 ═CH--CH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.94(3H, t, J=7.4Hz), 2.16- 184-186 2.30(8H, m), 4.31-4.34 (2H, m), 5.09-5.18(2H, m), 5.79(1H, m), 6.54(2H, s), 6.77(1H, s), 9.32 (1H, s)58 CH.sub.3 C.tbd.C--CH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.94(3H, t, J=7.5Hz), 1.69 152-154 (3H, t, J=2.4Hz), 2.22 (2H, q, J=7.5Hz), 4.49(2H, q, J=2.4Hz), 6.62(2H, s), 6.79 (1H, s), 8.93(1H, s)59 trans PhCH═CH-- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.94(3H, t, J=7.5Hz), 2.16- 174-175 CH.sub.2 -- 2.25(8H, m), 4.47-4.50 (2H, m), 6.12(1H, m), 6.38 (1H, d, J=15.8Hz), 6.55 (2H, s), 6.42(1H, s), 7.20- 7.30(5H, m), 9.39(1H, s)60 HC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.96(3H, t, J=7.4Hz), 2.19- 178-179 2.33(9H, m), 4.54 (2H, d, J=2.4Hz), 6.63(2H, s), 6.81(1H, s), 9.04(1H, s)61 PhC.tbd.CCH.sub.2 -- CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.93(3H, t, J=7.4Hz), 2.15- 128-129 2.24(8H, m), 4.78(2H, s), 6.65(2H, s), 6.75(1H, s), 7.20-7.29(5H, m), 8.79 (1H, s)62 trans CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.87-0.99(6H, m), 1.98(2H, 145-146 CH.sub.3 CH.sub.2 CH═CH-- q, J=7.4Hz), 2.21 (2H, q, CH.sub.2 -- J=7.4Hz), 2.31 (6H, s), 4.25-4.30(2H, m), 5.31- 5.65(2H, m), 6.55(2H, s), 6.78(1H, s), 8.25(1H, s)63 trans CH.sub.3 CH.sub.2 -- CH.sub.3 CH.sub.3 O 0.96(3H, t, J=7.4Hz), 2.17- 188-189 CH.sub.3 O.sub.2 CCH═CH-- 2.73(8H, m), 3.73(3H, s), CH.sub.2 -- 4.46-4.49(2H, m), 5.83(1H, m), 6.53 (2H, s), 6.77- 6.85 (2H, m)64 trans (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 1.13(6H, d, J=7.0Hz), 1.59 141-143 CH.sub.3 CH═CH--CH.sub.2 -- (3H, d, J=5.0Hz), 2.29(6H, s), 2.78(1H, m), 4.20(2H, d, J=5.5Hz), 5.34-5.61(2H, m), 6.51(2H, s), 6.75(1H, s), 8.75(1H, s)65 trans PhCH═CH-- (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 1.15(6H, d, J=7.0Hz), 2.27 157-158 CH.sub.2 -- (6H, s), 2.79 (1H, m), 4.46 (2H, d, J=6.2 Hz), 6.11 (1H, m), 6.37 (1H, d, J= 15.9Hz), 6.56(2H, s), 6.75 (1H, s), 7.21-7.32(5H, m)66 trans (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 1.15(6H, d, J=7.0Hz), 2.30 187-188 CH.sub.3 O.sub.2 CCH═CH-- (6H, s), 2.81(1H, m), 3.73 CH.sub.2 -- (3H, s), 4.44(2H, d, J=5.5 Hz), 5.78(1H, d, J=15.8 Hz),6.52(2H, s), 6.72- 6.86(2H, m), 9.34(1H, s)67 PhC.tbd.CCH.sub.2 -- (CH.sub.3).sub.2 CH-- CH.sub.3 CH.sub.3 O 1.15(6H, d, J=7.0Hz), 2.26 186-187 (6H, s), 2.79(1H, m), 4.75 (2H, s), 6.44(2H, s), 6.76 (1H, s), 7.21-7.33(5H, m), 8.82 (1H, s)__________________________________________________________________________
EXAMPLE 68
Synthesis of 1-(cis-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a solution of 49 mg (0.15 mmol) of the compound obtained from Example 49 in 1 ml of methanol were added 3 ml of pyridine, a drop of quinoline, and 3 mg of palladium on barium sulfate. The reaction mixture was then stirred for about 2 hours at room temperature under an atmosphere of hydrogen, filtered through Cellite pad, and evaporated under reduced pressure to give a light brown oil, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 22 mg (yield 45%) of the title compound as a white solid.
M.p.: 199° to 200° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.96(3H, t, J=7.3 Hz), 1.43(3H, dd, J=7.0 Hz, 1.8 Hz), 2.02(1H, m), 2.30(1H, m), 2.40(6H, s), 4.09(1H, m), 4.43(1H, m), 5.23-5.54(2H, m), 7.34(1H, s), 7.52(2H, s), 8.45(1H, s)
EXAMPLE 69
Synthesis of 1-(cis-cinnamyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a solution of 40 mg (0.1 mmol) of the compound obtained from Example 50 in 1 ml of methanol were added 3 ml of pyridine, a drop of quinoline, and 4 mg of palladium on barium sulfate. The reaction mixture was then stirred for about 2 hours at room temperature under an atmosphere of hydrogen, filtered through Cellite pad, and evaporated under reduced pressure to give a light brown oil, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:3) as an eluent to afford 28 mg (yield 69%) of the title compound as a white solid.
M.p.: 98° to 99° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.95(3H, t, J=7.3 Hz), 1.99(1H, m), 2.17-2.39(7H, m), 4.35(1H, m), 4.65(1H, m), 5.56(1H, m), 6.43(1H, d, J=11.6 Hz), 6.90-6.94(2H, m), 7.12-7.27(6H, m), 9.40(1H, s)
EXAMPLE 70
Synthesis of 1-(cis-2-butenyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione
To a solution of 40 mg (0.13 mmol) of the compound obtained from Example 58 in 1 ml of methanol were added 3 ml of pyridine, a drop of quinoline, and 4 mg of palladium on barium sulfate. The reaction mixture was then stirred for about 2 hours at room temperature under an atmosphere of hydrogen, filtered through Cellite pad, and evaporated under reduced pressure to give a light brown oil, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:3) as an eluent to afford 32 mg (yield 80%) of the title compound as a white solid.
M.p.: 181° to 182° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.94(3H, t, J=7.5 Hz), 1.61(3H, dd, J=7.0 Hz, 1.5 Hz), 2.20(2H, q, J=7.5 Hz), 2.30(6H, s), 4.39(2H, d, J=7.0 Hz), 5.33-5.66(2H, m), 6.55(2H, s), 6.77(1H, s), 8.91(1H, s)
EXAMPLE 71
Synthesis of 1-(cis-2-butenyl)-5-isopropyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione
To a solution of 33 mg (0.1 mmol) of the compound obtained from Example 11 in 1 ml of methanol were added 3 ml of pyridine, a drop of quinoline, and 4 mg of palladium on barium sulfate. The reaction mixture was then stirred for about 2 hours at room temperature under an atmosphere of hydrogen, filtered through Cellite pad, and evaporated under reduced pressure to give a light brown oil, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:3) as an eluent to afford 25 mg (yield 76%) of the title compound as a white solid.
M.p.: 141° to 142° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.13(6H, d, J=7.1 Hz), 1.61(3H, dd, J=6.9 Hz, 1.4 Hz), 2.31(6H, s), 2.79(1H, m), 4.35(2H, d, J=6.8 Hz), 5.38(1H, m), 5.60(1H, m), 6.54(2H, s), 6.77(1H, s)
EXAMPLE 72
Synthesis of 1-(ethoxycarbonylallyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedion
To a solution of 100 mg (0.27 mmol) of the compound obtained from Example 8 in 10 ml of anhydrous ethanol was added 20 mg of p-toluenesulfonic acid monohydrate. The reaction mixture was refluxed with stirring for about 48 hours, neutralized with sodium bicarbonate, and evaporated under reduced pressure to give a light brown residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 60 mg (yield 58%) of the title compound as a white solid.
M.p.: 157° to 158° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.98(3H, t, J=7.4 Hz), 1.22(3H, t, J=7.0 Hz), 2.07(1H, m), 2.27(1H, m), 2.39(6H, s), 4.08-4.37(4H, m), 5.66(1H, m), 6.66(1H, m), 7.33(1H, s), 7.51(2H, s), 9.24(1H, s)
EXAMPLE 73
Synthesis of 1-(isopropoxycarbonylallyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a stirred solution of 100 mg (0.27 mmol) of the compound obtained from Example 8 in 10 ml of isopropyl alcohol was added 20 mg of p-toluenesulfonic acid monohydrate. The reaction mixture was refluxed with stirring for about 24 hours, neutralized with sodium bicarbonate, and evaporated under reduced pressure to give a light brown residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:1) as an eluent to afford 40 mg (yield 37%) of the title compound as a white solid.
M.p.: 175° to 176° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.95(3H, t, J=7.4 Hz), 1.19(6H, d, J=6.0 Hz), 2.07(1H, m), 2.25(1H, m), 2.38(6H, s), 4.25-4.32(2H, m), 4.96(1H, m), 5.60(1H, m), 6.61(1H, m), 7.30(1H, s), 7.48(2H, s), 9.74(1H, s)
EXAMPLE 74
Synthesis of 1-(4-azido-trans-2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a stirred solution of 187 mg (0.5 mmol) of the compound obtained from Example 9 in 5 ml of DMF was added 98 mg (1.5 mmol) of sodium azide at room temperature. After 24 hours, the reaction mixture was diluted with ether, washed with water, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give a yellow oil, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 180 mg (yield 94%) of the title compound as a white solid.
M.p.: 126° to 127° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.14(3H, d, J=6.8 Hz), 1.21(3H, d, J=6.8 Hz), 2.31(1H, m), 2.39(6H, s), 3.60(2H, d, J=5.4 Hz), 4.03(1H, m), 4.31(1H, dd, J=15.8 Hz, 6.6 Hz), 5.40-5.70(2H, m), 7.34(1H, s), 7.53(2H, s), 9.91(1H,s)
EXAMPLE 75
Synthesis of 1-(4-acetoxy-trans-2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a solution of 187 mg (0.5 mmol) of the compound obtained from Example 9 in 5 ml of DMF was added 410 mg (5 mmol) of sodium acetate. The reaction mixture was then stirred for about 48 hours at 100° C., and evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 140 mg (yield 70%) of the title compound as a colorless syrup.
1 H-NMR(200 MHz, CDCl 3 ) δ 1.22(3H, d, J=6.9 Hz), 1.27(3H, d, J=6.8 Hz), 2.03(3H, s), 2.29(1H, m), 2.40(6H, s), 4.15(2H, m), 4.35(2H, d, J=4.7 Hz), 5.45-5.60(2H, m), 7.34(1H, s), 7.53(2H, s), 8.88(1H, s)
EXAMPLE 76
Synthesis of 1-(4-hydroxy-trans-2-butenyl)-5-isopropyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a stirred solution of 80 mg (0.2 mmol) of the compound obtained from Example 75 in 5 ml of methanol was added 20 mg (0.37 mmol) of sodium methoxide at room temperature. After 1 hour, the reaction mixture was neutralized with acetic acid and evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (4:1) as an eluent to afford 60 mg (yield 82%) of the title compound as a colorless syrup.
1 H-NMR(200 MHz, CDCl 3 ) δ 1.12(3H, d, J=6.8 Hz), 1.19(3H, d, J=6.8 Hz), 2.26-2.38(7H, m), 3.94-4.05(3H, m), 4.26(1H, dd, J=14.9 Hz, 4.4 Hz), 5.53-5.60(2H, m), 7.33(1H, s), 7.52(2H, s), 9.56(1H, s)
EXAMPLE 77
Synthesis of 1-(carboxyallyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione
To a stirred solution of 561 mg (1.5 mmol) of the compound obtained from Example 21 in 11 ml of methanol-water (10:1) was added 120 mg (3 mmol) of sodium hydroxide. The reaction mixture was then refluxed for about 2 hours, acidified with dil. hydrochloric acid, and evaporated under reduced pressure to give a yellow residue, which was purified by flash chromatography using a mixture of methanol and chloroform (1:9) as an eluent to afford 100 mg (yield 19%) of the title compound as a foam.
1 H-NMR(200 MHz, CDCl 3 ) δ 1.08(3H, t, J=7.5 Hz), 2.28(6H, s), 2.75(2H, q, J=7.5 Hz), 4.75-4.77(2H, m), 5.62(1H, d, J=15.8 Hz), 6.73-6.87(4H,m), 10.02(1H, s)
EXAMPLE 78
Synthesis of 1-(4-hydroxy-trans-2-butenyl)-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione
With stirring, a solution of 112 mg (0.3 mmol) of the compound obtained from Example 21 in 3 ml of THF was cooled to -78° C. under nitrogen and then 440 μl (0.66 mmol) of 1.5M solution of diisobutyl aluminum hydride in toluene was added. The resulting mixture was then warmed to room temperature over about 1 hour and stirred for 2 hours at room temperature. The excess hydride was then decomposed by addition of methanol and the solvent was removed under reduced pressure to give an oily residue, which was purified by flash chromatography using a mixture of methanol and chloroform (1:10) as an eluent to afford 47 mg (yield 45%) of the title compound as a white solid.
M.p.: 157° to 158° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 1.05(3H, t, J=7.4 Hz), 2.28(6H, s), 2.71(2H, q, J=7.4 Hz), 4.03-4.09(2H, m), 4.59-4.62(2H, m), 5.62-5.70(2H, m), 6.76(2H, s), 6.88(1H, s), 9.17(1H, s)
EXAMPLE 79
Synthesis of 1-(4-azido-trans-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a stirred solution of 200 mg (0.55 mmol) of the compound obtained from Example 47 in 5 ml of DMF was added 108 mg (1.66 mmol) of sodium azide at room temperature. After 18 hours, the reaction mixture was diluted with ether, washed with water, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 184 mg (yield 90%) of the title compound as a white solid.
M.p.: 119° to 120° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.96(3H, t, J=7.4 Hz), 2.04(1H, m), 2.29(1H, m), 2.40(6H, s), 3.63(2H, d, J=5.5 Hz), 4.06(1H, m), 4.36(1H, m), 5.41-5.68(2H, m), 7.35(1H, s), 7.52(2H, s), 9.44(1H, s)
EXAMPLE 80
Synthesis of 1-(4-acetoxy-trans-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a solution of 180 mg (0.5 mmol) of the compound obtained from Example 47 in 5 ml of DMF was added 410 mg (5 mmol) of sodium acetate. The reaction mixture was then stirred for about 40 hours at 100° C. and evaporated under reduced pressure to give a yellow residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:2) as an eluent to afford 110 mg (yield 57%) of the title compound as a white solid.
M.p.: 152° to 153° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.94(3H, t, J=7.4 Hz), 1.94-2.15(4H, m), 2.23(1H,m), 2.37(6H, s), 4.00-4.35(4H, m), 5.44-5.65(2H, m), 7.32(1H, s), 7.49(2H, s), 9.67(1H,s)
EXAMPLE 81
Synthesis of 1-(4-hydroxy-trans-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a stirred solution of 50 mg (0.13 mmol) of the compound obtained from Example 80 in 5 ml of methanol was added 20 mg (0.37 mmol) of sodium methoxide at room temperature. After 1 hour, the reaction mixture was neutralized with acetic acid and evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (4:1) as an eluent to afford 26 mg (yield 56%) of the title compound as a white solid.
M.p.: 172° to 173° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.96(3H, t, J=7.4 Hz), 2.01(1H, m), 2.31(1H, m), 2.40(6H, s), 3.94-4.37(4H, m), 5.57-5.62(2H, m), 7.34(1H, s), 7.52(2H, s), 9.46(1H,s)
EXAMPLE 82
Synthesis of 1-(4-methoxy-trans-2-butenyl)-5-ethyl-6-(3,5-dimethylbenzoyl)-2,4-pyrimidinedione
To a stirred solution of 60 mg (0.17 mmol) of the compound obtained from Example 47 in 2 ml of methanol was added 50 mg (2.17 mmol) of sodium under nitrogen at room temperature. After 48 hours, the reaction mixture was neutralized with acetic acid and evaporated under reduced pressure to give a yellow-colored residue, which was purified by flash chromatography using a mixture of ethyl acetate and hexane (1:1) as an eluent to afford 30 mg (yield 50%) of the title compound as a white solid.
M.p.: 142° to 143° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.95(3H, t, J=7.5 Hz), 2.01(1H, m), 2.27(1H, m), 2.39(6H, s), 3.24(3H, s), 3.73(2H, d, J=4.4 Hz), 4.07(1H, m), 4.32(1H, m), 5.45-5.64(2H, m), 7.33(1H, s), 7.51(2H, s)
EXAMPLE 83
Synthesis of 1-(4-hydroxy-trans-2-butenyl)-5-ethyl-6-(3,5-dimethylphenoxy)-2,4-pyrimidinedione
With stirring, a solution of 179 mg (0.53 mmol) of the compound obtained from Example 63 in 5 ml of THF was cooled to -78° C. under nitrogen and 1 ml (1.5 mmol) of 1.5M solution of diisobutyl aluminum hydride in toluene was added. The reaction mixture was then warmed to room temperature over about 2 hours, then stirred for 14 hours at room temperature. The excess hydride was then decomposed by addition of methanol and the solvent was removed under reduced pressure to give an oily residue, which was purified by flash chromatography using ether as an eluent to afford 66 mg (yield 40%) of the title compound as a white solid.
M.p.: 125° to 126° C. 1 H-NMR(200 MHz, CDCl 3 ) δ 0.94(3H, t, J=7.4 Hz), 2.15-2.30(8H, m), 4.04-4.06(2H, m), 4.33-4.35(2H, m), 5.67-5.72(2H, m), 6.54(2H, s), 6.77(1H, s), 9.06(1H,s)
Antiviral Activity and Toxicity Test
The anti-HIV assays were based on the inhibition of the virus-induced cytopathic effect in MT-4 cells as described in J. Virol. Methods, 16, 171 (1987). Briefly, MT-4 cells were suspended in culture medium at 2.5×10 5 cells/ml and infected with 1000 CCID 50 (50% cell culture infective dose) of HIV. Immediately, after virus infection, 100 μl of the cell suspension was brought into each well of a flat-bottomed microtiter tray containing various concentrations of the test compounds. After a 4 or 5 day incubation at 37° C., the number of viable cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method, as disclosed in J. Virol. Methods, 20, 309 (1988).
The cytotoxicity of the compounds of the present invention was assessed in parallel with their antiviral activity. It was based on the viability of mock-infected host cells as determined by the MTT methods (se J. Virol. Methods, 20, 309 (1988)).
The results of the tests are shown in Table 2.
TABLE 2______________________________________Ex. No. CD.sub.50 (μg/ml) ED.sub.50 (μg/ml) S.I. (CD.sub.50 /ED.sub.50)______________________________________ 1 14.85 <0.32 >46 2 8.73 <0.32 >29 3 7.94 <0.009 >882 4 52.5 <0.32 >164 5 48.59 <0.032 >1,518 6 8.03 <0.009 >892 7 27.84 <0.33 >84 8 27.24 <0.19 >143 9 6.38 <0.009 >70810 19.39 <0.01 >1,93911 39.87 <0.32 >12412 17.48 <0.32 >5413 16.17 <0.32 >5014 5.77 <0.032 >18015 11.26 0.36 3116 19.03 2.78 6.8517 5.79 3.68 1.5718 3.9 <0.032 >12119 8.74 <0.0.09 >97120 5.21 <0.009 >57821 41.42 <0.32 >12922 33.8 <0.36 >9323 38.2 <0.93 >4124 1.81 <0.032 >5625 62.5 <0.69 >9026 4.93 <0.009 >54727 6.66 <0.009 >74028 5.79 <0.009 >64329 37.15 <0.023 >1,61530 17.7 <0.009 >1,96631 16.94 <0.32 >5232 32.36 <0.32 >10133 8.58 <0.032 >26834 12.33 <0.32 >3835 5.78 <0.009 64236 22.07 <0.33 6637 12.47 1.64 7.638 24.15 <0.32 >7539 8.65 <0.049 >17640 5.02 <0.009 >55741 21.04 0.01 >2,10442 7.42 <0.009 >82443 54.51 <0.17 >32044 34.39 <0.01 >3,43945 5.97 <0.009 >66346 9.14 <0.009 >1,01547 6.7 <0.009 >77448 36.38 <0.39 >9349 5.2 <0.032 >16250 4.34 <0.009 >48251 22.26 <0.01 >2,47352 9.75 <0.009 >1,08353 5.99 <0.009 >66554 30.05 <0.01 >3,00555 41.66 <0.32 >13056 6.76 <0.009 >75.157 42.39 <0.32 >13258 48.9 <0.34 >14359 38.56 <0.23 >16760 15.76 <0.62 >2561 9.3 <0.009 >1,03362 8.05 <0.032 >25163 7.17 <0.032 >22464 9.89 <0.009 >1,09865 8.04 <0.009 >89366 78.64 <0.32 >24567 7.6 <0.009 >84468 8.21 <0.032 >16269 8.67 <0.032 >27070 73.81 <0.01 >7,38171 7.71 <0.0155 >49772 6.85 <0.01 >68573 4.85 <0.01 >48574 8.59 <0.009 >95475 58.39 <0.009 >6,48776 41.98 <0.025 >1,67977 68.34 <0.902 >7578 28.97 <0.97 >2979 8.2 <0.009 >91180 44.4 <0.033 >1,34584 55.44 <0.009 >6,16082 43.1 <0.32 >13483 25.5 <0.81 >31Ref. 1 44.66 <0.009 >4,962Ref. 2 6.05 <0.009 >672______________________________________ Footnote: ED.sub.50 : Effective concentration for the inhibition of the proliferation of HIV by 50% CD.sub.50 : Cytotoxic concentration that causes death of cells by 50% S.I.: Selectivity index (CD.sub.50 /ED.sub.50) Ref. 1: 1ethoxymethyl-5-ethyl-6-(3,5-dimethylbenzyl)-2,4-pyrimidinedione Ref. 2: 1benzyloxymethyl-5-ethyl-6-(3,5-dimethylphenylthio)-2,4-pyrimidinedione
While the invention has been described in connection with the above specific embodiments, it should be recognized that various modifications and changes may be made to the present invention and also fall within the scope of the invention as defined by the claims that follow. | Novel 2,4-pyrimidinedione compounds, and pharmaceutically acceptable salts thereof which possess good antiviral activities, and specifically represented by the following formula(I): ##STR1## wherein: R 1 represents an unsubstituted or substituted allyl group represented by CH 2 CH═CR 5 R 6 or an unsubstituted or substituted propargyl group represented by CH 2 C.tbd.CR 7 wherein R 5 , R 6 and R 7 are each independently a hydrogen atom; a methyl group optionally substituted with a halogen atom, or a C 1-10 carbonyloxy, hydroxy, azido, cyano, optionally substituted amino, optionally substituted phosphonyl, optionally substituted phenyl, C 3-10 heteroaryl, C 1-3 alkoxy or benzyloxy radical; a C 2-10 alkyl or alkenyl group; a cyclopropyl group; an optionally substituted phenyl group; a C 3-10 heteroaryl group; a C 1-10 ester group; or an optionally substituted C 1-10 alkylamide group;
R 2 represents a halogen atom, an optionally substituted C 1-5 alkyl, C 3-6 cycloalkyl, C 2-8 alkenyl, C 2-8 alkynyl group or a benzyl group;
R 3 and R 4 represent independently a hydrogen or halogen atom, or a hydroxy, C 1-3 alkyl, fluoromethyl, C 1-3 alkoxy, amino, C 2-6 alkylester or C 2-7 alkylamide group;
A represents an oxygen or sulfur atom;
Z represents an oxygen or sulfur atom; a carbonyl group; an amino group; or a methylene group optionally substituted with at least one selected from the group consisting of a halogen atom, and a cyano, hydroxy, azido, amino, C 1-3 alkylamide, C 1-4 ester, and nitro groups. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2009-192596, filed Aug. 21, 2009, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a light source device, projection apparatus, and projection method suitable for a projector apparatus or the like.
2. Description of the Related Art
For example, in Pat. Document 1 (Jpn. Pat. Appln. KOKAI Publication No. 2004-341105), in a projection display apparatus, in order to carry out color display, a surface light source emitting primary-color light of each of red, green, and blue, and spatial light modulator corresponding thereto are required, and hence the number of pieces of components are increased, and downsizing, weight saving, and price reduction of the overall apparatus cannot be achieved. Thus, technique in which a light-emitting diode emitting ultraviolet is used as a light source, a visible light reflection film having characteristics of transmitting ultraviolet light, and reflecting visible light is formed on a surface of a color wheel irradiated with ultraviolet light from the light-emitting diode, and a fluorescent substance layer emitting visible light corresponding each of red, green, and blue by ultraviolet light irradiation is formed on the back surface side of the color wheel is contrived.
However, including the technique described in above Pat. Document, conventional techniques have problems. FIGS. 5A and 5B exemplify a change in color of light emitted from the light source side of a case where a single light source and color wheel are used. FIG. 5A shows the configuration of a color wheel 1 constituted of color filters 1 R, 1 G, and 1 B of red, green, and blue in each of which a central angle is set at 120°. The rotational position of the color wheel to be inserted in the light path from the light source is indicated by an angle from 0 to 360° of the rotational phase corresponding to the image frame.
In this color wheel 1 , as shown in FIG. 5A , the color filter 1 B of blue, color filter 1 R of red, and color filter 1 G of green are arranged in the order mentioned in the light path from the light source. FIG. 5B shows the color of the light-source light applied to the micromirror element configured to display an image, and color of the light-source light exiting from the color wheel 1 .
As shown in FIG. 5B , a single light source is used to select light transmitted through each color filter, the selected light is applied to the micromirror element, and a light figure is formed by the reflected light of the micromirror element. For that reason, the color of the light-source light applied to the micromirror element, and color of the light-source light exiting from the color wheel 1 coincide with each other.
As shown in FIG. 5A , in the color wheel 1 , the central angle of each of the color filters 1 B, 1 R, and 1 G is fixedly constituted, and hence it is physically impossible to vary the width of each of the blue, red, and green field periods in the period of 360° in which the color wheel 1 rotates.
Accordingly, there has been the problem that it is not possible to cope with, for example, a change or the like in the transmission wavelength band characteristics of the color filter due to aged deterioration, or deal with the statuses of use desired by various users such as a case where adjustment of color balance is required, case where emphasis on the brightness of the image is more desired than the color reproducibility, and the like.
BRIEF SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a technique capable of responding to a desired color environment such as color balance, brightness of the projected image, or the like, as needed.
According to one aspect of the present invention, there is provided a light source device comprising: a first light source configured to emit light in a first wavelength band; a light-source light generation section configured to generate light of each of a plurality of colors by time division by using the first light source; a second light source configured to generate light of a second wavelength band different from the first wavelength band; and a light source control section configured to cause each of the light-source light generation section and the second light source to generate light in one period, and to control a drive timing of each of the first and second light sources to adjust a light-emission timing and a light-emission period of light generated by each of the light-source light generation section and the second light source.
According to another aspect of the present invention, there is provided a projection apparatus comprising: a first light source configured to emit light in a first wavelength band; a light-source light generation section configured to generate light of each of a plurality of colors by time division by using the first light source; a second light source configured to generate light of a second wavelength band different from the first wavelength band; a light source control section configured to cause each of the light-source light generation section and the second light source to generate light in one period, and to control a drive timing of each of the first and second light sources to adjust a light-emission timing and a light-emission period of the light generated by each of the light-source light generation section and the second light source; an input section configured to input an image signal; and a projection section configured to form and project a light figure of each color corresponding to the image signal input by the input section by using light generated from each of the light-source light generation section and the second light source under control carried out by the light source control section.
According to still another aspect of the present invention, there is provided a projection method applied to a projection apparatus including a first light source configured to emit light in a first wavelength band, a light-source light generation section configured to generate light of each of a plurality of colors by time division by using the first light source, a second light source configured to generate light of a second wavelength band different from the first wavelength band, an input section configured to input an image signal, and a projection section configured to form and project a light figure of each color corresponding to the image signal input by the input section by using light generated from each of the light-source light generation section and the second light source, the method comprising: causing each of the light-source light generation section and the second light source to generate light in one period, and controlling a drive timing of each of the first and second light sources to adjust a light-emission timing and a light-emission period of the light generated by each of the light-source light generation section and the second light source.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.
FIG. 1 is a block diagram showing the functional circuit configuration of an overall data projector apparatus according to an embodiment of the present invention;
FIG. 2 is a view mainly showing the specific optical configuration of a light-source system according to the embodiment of the present invention;
FIGS. 3A , 3 B, and 3 C are views respectively showing the configuration of a color wheel, and projection operation timing at each of the normal mode time, and green-emphasized mode time according to the embodiment of the present invention;
FIGS. 4A , 4 B, and 4 C are views respectively showing the configuration of a color wheel, and projection operation timing at each of the normal mode time, and luminance-emphasized mode time according to another operation example of the embodiment of the present invention; and
FIGS. 5A and 5B are views respectively showing the configuration of a color wheel used in a general projector apparatus of the DLP (registered trademark) system, and relationship between the configuration and the color of outgoing light based on the color wheel.
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a case where the present invention is applied to a data projector apparatus of the DLP (registered trademark) system will be described below with reference to the drawings.
FIG. 1 is a block diagram showing the schematic functional configuration of an electronic circuit provided in a data projector apparatus 10 according this embodiment.
A reference symbol 11 in FIG. 1 denotes an input/output connector section, which includes, for example, a pin-jack (RCA) type video input terminal, D-sub 15 type RGB input terminal, and Universal Serial Bus (USB) connector.
Image signals of various standards to he input from the input/output connector section 11 are input to an image conversion section 13 through an input/output interface 12 , and system bus SB.
The image conversion section 13 converts the input image signals into image signals of a predetermined format suitable for projection, appropriately writes the image signals onto a video RAM 14 which is a buffer memory for display, thereafter reads the written image signals, and transmits the read image signals to a projection image processing section 15 .
At this time, data such as symbols or the like indicating various operational states for On Screen Display (DSD) are superimposed on the image signals read from the video RAM 14 as the need arises, and the resultant image signals are written onto the video RAM 14 again. Thereafter, the processed image signals are read and transmitted to the projection image processing section 15 .
The projection image processing section 15 display-drives a micromirror element 16 which is a spatial light modulation (SLM) element by time-division drive of higher speed obtained by multiplying a frame rate conforming to a predetermined format, for example, 120 frames/second by a division number of color components, and display gradation number in accordance with image signals transmitted thereto.
The micromirror element 16 forms a light figure by the light reflected therefrom by individually subjecting each of inclination angles of a plurality of minute mirrors arranged in an array corresponding to, for example, XGA (1024 pixels in the lateral direction×768 pixels in the longitudinal direction) to an on/off operation at high speed.
On the other hand, primary-color light components of red, green, and blue are cyclically emitted from a light source section 17 by time division. Each of the primary-color light components of red, green, and blue from the light source section 17 is reflected from a mirror 18 , and is applied to the micromirror element 16 . Further, a light figure is formed by the reflected light of the micromirror element 16 , and the formed light figure is projection-displayed on a screen (not shown) which is a projection object through a projector lens unit 19 .
The light source section 17 the specific optical configuration of which will be described later, includes two types of light sources, i.e., a semiconductor laser 20 emitting blue laser light, and LED 21 emitting red light.
The blue laser light emitted from the semiconductor laser 20 is reflected from a mirror 22 , is thereafter transmitted through a dichroic mirror 23 , and is then applied to one point on the circumference of a color wheel 24 . The color wheel 24 is rotated by a motor 25 . On the circumference of the color wheel 24 irradiated with the laser light, a green fluorescent reflection plate 24 G and blue light transmission diffusion plate 24 B are jointly formed into a ring-like shape.
When the green fluorescent reflection plate 24 G of the color wheel 24 is located at the irradiation position of the laser light, green light is excited by the irradiation of the laser light, the excited green light is reflected from the color wheel 24 , and is thereafter reflected also from the dichroic mirror 23 . Thereafter, the green light is further reflected from a dichroic mirror 28 , is formed into a light flux having substantially uniform luminance distribution by an integrator 29 , is thereafter reflected from a mirror 30 , and is then sent to the mirror 18 .
Further, when the blue light transmission diffusion plate 242 of the color wheel 24 is located at the irradiation position of the laser light as shown in FIG. 1 , the laser light is transmitted through the color wheel 24 while being diffused by the blue light transmission diffusion plate 24 B, and is thereafter reflected from each of mirrors 26 and 27 . Thereafter, the blue light is transmitted through the dichroic mirror 28 , is formed into a light flux having substantially uniform luminance distribution by the integrator 29 , is thereafter reflected from the mirror 30 , and is then sent to the mirror 18 .
Furthermore, the red light emitted from the LED 21 is transmitted through the dichroic mirror 23 , is thereafter reflected from the dichroic mirror 28 , is formed into a light flux having substantially uniform luminance distribution by the integrator 29 , is thereafter reflected from the mirror 30 , and is then sent to the mirror 18 .
As described above, the dichroic mirror 23 has the spectral characteristics of transmitting the blue and red light therethrough, whereas reflecting the green light.
Further, the dichroic mirror 28 has the spectral characteristics of transmitting the blue light, whereas reflecting the red and green light.
The light emission timing of each of the semiconductor laser 20 and LED 21 of the light source section 17 , and rotation of the color wheel 24 by the motor 25 are controlled by a projection light processing section 31 in a unifying manner. The projection light processing section 31 controls the light emission timing of each of the semiconductor laser 20 , and LED 21 , and the rotation of the color wheel 24 in accordance with the timing of the image data supplied from the projection image processing section 15 .
A CPU 32 executes a control operation in the data projector apparatus 10 by using a main memory 33 constituted of a DRAM, and program memory 34 constituted of an electrically rewritable nonvolatile memory in which an operation program, various standardized data items are stored.
The CPU 32 executes various projection operations in accordance with key operation signals from an operation section 35 .
The operation section 35 includes a key operation section provided on the main body of the data projector apparatus 10 , and laser reception section configured to receive infrared light from a remote controller (not shown) to be exclusively used for the data projector apparatus 10 , and directly outputs a key operation signal based on the key operated by the user by using the key operation section of the main body or the remote controller to the CPU 32 .
The operation section 35 is provided with, together with the above-mentioned key operation section and remote controller, for example, a focus adjustment key (FOCUS), zoom adjustment key (ZOOM), input image switching key (INPUT), menu key (MENU), cursor (←, →, ↑, and ↓) key, set key (ENTER), cancel key (ESC), and the like.
The CPU 32 described above is further connected also to a sound processing section 36 through the system bus SB. The sound processing section 36 is provided with a sound source circuit such as a PCM sound source or the like, converts the sound data supplied thereto at the time of the projection operation into analog data, drives a speaker section 37 to loudspeaker-release the sound or generate beep sound or the like as the need arises.
Next, a specific configuration example of the optical system of the light source section 17 is mainly shown by FIG. 2 . FIG. 2 is a view expressing the configuration of the periphery of the light source section 17 in the plane layout.
For example, three semiconductor lasers 20 A, 20 B, 20 C, having the same light-emitting characteristics, are provided. The laser light of each of these semiconductor lasers 20 A, 20 B, 20 C is blue and, for example, the emission wavelength is about 450 nm.
The blue light oscillated by each or these semiconductor lasers 20 A, 20 B, 20 C is made substantially parallel with each other through each of lenses 41 A to 41 C, is then reflected from each of mirrors 20 A, 20 B, 20 C, is passed through lenses 42 and 43 , is thereafter transmitted through the dichroic mirror 23 , then is transmitted through a lens group 44 , and is then applied to the color wheel 24 .
In this embodiment, the lenses 42 and 43 , and lens group 44 constitute a light-condensation optical system configured to condense the substantially paralleled blue light at the position of the color wheel 24 on the optical axis.
On the color wheel 24 , as described above, the blue light transmission diffusion plate 24 B, and green fluorescent reflection plate 24 G are positioned to constitute a ring on the same circumference.
When the green fluorescent reflection plate 24 G of the color wheel is located at the irradiation position of the blue light, green light of a wavelength range centering on a wavelength of about 530 nm is excited by the irradiation. The excited green light is reflected from the reflection surface of the color wheel 24 , and is thereafter reflected also from the dichroic mirror 23 through the lens group 44 .
The green light reflected from the dichroic mirror 23 is further reflected from the dichroic mirror 28 through the lens 45 , and is guided to the integrator 29 through a lens 46 . In this embodiment, the lens group 44 , lens 45 , and lens 46 are designed to form a light guiding optical system 1 configured to guide the green light excited at the color wheel 24 to the integrator 29 in which the beam size of the green light fits in the aperture size of the integrator 29 . The magnifying power of the light guiding optical system is designed to substantially coincide with the ratio of the aperture size of the integrator 29 to the irradiation size of the light to be applied to the color wheel 24 .
Further, the green light is formed into a light flux having substantially uniform luminance distribution by the integrator 29 , is thereafter reflected from the mirror 30 through a lens 47 , and is sent to the mirror 18 through a lens 48 .
The green light reflected from the mirror 18 is then applied to the micromirror element 16 through a lens 49 . Further, a light figure of the green component is formed by the reflected green light, and is projected on the outside through the lens 49 , and projector lens unit 19 .
Further, when the blue light transmission diffusion plate 24 B of the color wheel 24 is located at the irradiation position of the blue light, the blue light is transmitted through the color wheel 24 while being diffused by the blue light transmission diffusion plate 24 B with lower diffusion characteristics than the green light excited by substantially perfect diffusion light. Furthermore, the blue light is reflected from the mirror 26 through a lens 50 located on the back side.
The motor 25 configured to rotate the color wheel 24 is arranged on the same side as the lens 50 configured to condense the blue light transmitted through the color wheel 24 . The blue light transmitted through the color wheel 24 has lower diffusion than the green light reflected from the color wheel 24 , and hence it is possible to make the size of the lens 50 smaller than the lens group 44 configured to condense the green light reflected from the color wheel 24 .
Furthermore, the blue light is reflected from the mirror 27 through a lens 51 , is passed through a lens 52 , is then transmitted through the dichroic mirror 28 , and is guided to the integrator 29 through the lens 46 . In this embodiment, the lenses 50 , 51 , 52 , and 46 are designed to form a light guiding optical system configured to guide the blue light transmitted through the color wheel 24 to the integrator 29 in which the beam size of the blue light fits in the aperture size of the integrator 29 . The magnifying power of the light guiding optical system is designed to substantially coincide with the ratio of the aperture size of the integrator 29 to the irradiation size of the light to be applied to the color wheel 24 .
Further, the blue light is formed into a light flux having substantially uniform luminance distribution by the integrator 29 , is thereafter reflected from the mirror 30 through the lens 47 , and is sent to the mirror 18 through the lens 48 .
The blue light reflected from the mirror 18 is then applied to the micromirror element 16 through the lens 49 . Further, a light figure of the blue component is formed by the reflected blue light, and is projected on the outside through the lens 49 , and projector lens unit 19 .
On the other hand, the LED 21 emits red light of, for example, a wavelength of 620 nm. The red light emitted from the LED 21 is transmitted through the dichroic mirror 23 through a lens group 53 , is thereafter reflected from the dichroic mirror 28 through the lens 45 , and is further guided to the integrator 29 through the lens 46 . In this embodiment, the lens group 53 , lens 45 , and lens 46 are designed to form a light guiding optical system configured to guide the red light emitted in the emission size of the LED 21 to the integrator 29 in which the beam size of the red light fits in the aperture size of the integrator 29 . The magnifying power of the light guiding optical system is designed to substantially coincide with the ratio of the aperture size of the integrator 29 to the emission size of the LED 21 .
Further, the red light is formed into a light flux having substantially uniform luminance distribution by the integrator 29 , is thereafter reflected from the mirror 30 through the lens 47 , and is sent to the mirror 18 through the lens 48 .
Further, the LED 21 is arranged near the semiconductor lasers 20 A, 20 B, 20 C, and in a direction in which the optical axis thereof is parallel with those of the semiconductor lasers 20 A, 20 B, 20 C. By arranging the LED 21 in this way, it becomes easy to integrate, although not shown, a heat sink provided on the back side of the LED 21 , and configured to cool the LED 21 , and heat sink provided on the back side of the semiconductor lasers 20 A, 20 B, 20 C, and configured to cool the semiconductor lasers with each other, and it is further possible to reduce the size of the overall apparatus, and reduce the number of pieces of the components.
The red light reflected from the mirror 18 is then applied to the micromirror element 16 through the lens 49 . Further, a light figure of the red component is formed by the reflected red light, and is projected on the outside through the lens 49 , and projector lens unit 19 .
Next, an operation of the embodiment will be described below.
In this embodiment, as shown in FIG. 3A , the blue light transmission diffusion plate 24 B constituting the color wheel 24 is arranged on a part of the circumference having a central angle of about 150° at a position of 0° to about 150° in the rotational phase corresponding to the image frame. On the other hand, the green fluorescent reflection plate 24 G is arranged on a part of the circumference having a central angle of about 210° at a position of about 150 to 360° (0°) in the same rotational phase.
Here, it is assumed that it is possible to switch the mode between the normal mode and green-emphasized mode as two color modes.
In the normal mode, as shown in FIG. 3B , the continued time ratio of periods in which the primary color images of blue, red, and green constituting one frame of the color image to be projected are projected is made 1:1:1.
The periods in which the primary color images of blue, red, and green are projected are defined as the B-, R- and G-fields, respectively.
That is, the continued time ratio b:r:g of the B-, R- and G-fields becomes 120°:120°:120° in terms of the central angles of the color wheel 24 with respect to 360° corresponding to one rotation of the color wheel 24 rotating at a constant rotational speed.
In the green-emphasized mode on the other side, as shown in FIG. 3C , the continued time ratio of periods in which the primary color images of blue, red, and green constituting one frame of the color image are projected is made 10:11:15.
That is, the continued time ratio b:r:g of the B-, R- and G-fields becomes 100°:110°:150° in terms of the central angles of the color wheel 24 with respect to 360° corresponding to one rotation of the color wheel 24 rotating at a constant rotational speed.
All the operation control concomitant with the switching of the color mode is executed by the projection light processing section 31 under the centralized control of the CPU 32 .
FIG. 3B shows the relationship among the color of the light figure formed at the micromirror element 16 at the normal mode time, emission timing of the LED 21 , emission timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and output of the color wheel 24 .
At this normal mode time, at the beginning of one frame, in the period of the B-field corresponding to 120° in terms of the central angle of the color wheel 24 , blue light is emitted by the oscillation of the semiconductor lasers 20 A, 20 B, 20 C as shown by the CW output of FIG. 3B . Further, the blue light transmitted through the blue light transmission diffusion plate 24 B of the color wheel 24 , and diffused is applied to the micromirror element 16 .
At this time, an image corresponding to the blue light is displayed by the micromirror element 16 , whereby a blue light figure is formed by the reflected light thereof, and is projected onto an external projection object through the projector lens unit 19 . During this period, the LED 21 is kept in the off-state.
Thereafter, the on-state of the LED 21 is started in synchronization with a temporary stop of the oscillation of the semiconductor lasers 20 A, 20 B, 20 C. After that, in the period of the R-field corresponding to 120° in terms of the central angle of the color wheel 24 , red light is emitted by the on-state of the LED 21 , and is applied to the micromirror element 16 as shown by R-LED of FIG. 3B .
At this time, an image corresponding to the red light is displayed by the micromirror element 16 , whereby a red light figure is formed by the reflected light thereof, and is projected onto the external projection object through the projector lens unit 19 .
During this period, the oscillation of the semiconductor lasers 20 A, 20 B, 20 C is temporarily stopped. Accordingly, even when the blue light transmission diffusion plate 24 B or green fluorescent reflection plate 24 G of the color wheel 24 exists at the position on the optical axis, the oscillation of the semiconductor lasers 20 A, 20 B, 20 C is temporarily stopped, and hence neither blue light nor green light is generated as the light-source light.
Thereafter, in synchronization with turning-off of the LED 21 , the oscillation at the semiconductor laser 20 A, 20 B, 20 C is resumed. After that, in a period of the G-field corresponding to 120° in terms of the central angle of the color wheel 24 , green reflected light excited at the green fluorescent reflection plate 24 G of the color wheel 24 is applied to the micromirror element 16 as the light-source light.
At this time, an image corresponding to the green light is displayed by the micromirror element 16 , whereby a green light figure is formed by the reflected light thereof, and is projected onto the external projection object through the projector lens unit 19 .
Furthermore, the color wheel 24 rotates to terminate the G-field and one-frame periods.
Thereafter, when the blue light transmission diffusion plate 24 B is positioned again on the optical axis from the semiconductor lasers 20 A, 20 B, 20 C in place of the green fluorescent reflection plate 24 G, the B-field period of the next frame is started.
As described above, the oscillation-timing and turning-on-timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and LED 21 are controlled in synchronization with the rotation of the color wheel 24 on which the blue light transmission diffusion plate 24 B and green fluorescent reflection plate 24 G are formed. As a result of this, the green and blue light resulting from the oscillation of the semiconductor lasers 20 A, 20 B, 20 C, and red light resulting from the on-state of the LED 21 are cyclically generated by time division, and are applied to the micromirror element 16 .
Next, an operation at the green-emphasized mode time will be described below.
FIG. 3C shows the relationship among the color of the light figure formed at the micromirror element 16 at the green-emphasized mode time, emission timing of the LED 21 , emission timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and output of the color wheel 24 .
At this green-emphasized mode time, at the beginning of one frame, in the period of the B-field corresponding to 100° in terms of the central angle of the color wheel 24 , blue light is emitted by the oscillation of the semiconductor lasers 20 A, 20 B, 20 C as shown by the CW output of FIG. 3C . Further, the blue light transmitted through the blue light transmission diffusion plate 24 B of the color wheel 24 , and diffused is applied to the micromirror element 16 .
At this time, an image corresponding to the blue light is displayed by the micromirror element 16 , whereby a blue light figure is formed by the reflected light thereof, and is projected onto an external projection object through the projector lens unit 19 . During this period, the LED 21 is kept in the off-state.
Thereafter, the on-state of the LED 21 is started in synchronization with a temporary stop of the oscillation of the semiconductor lasers 20 A, 20 B, 20 C. After that, in the period of the R-field corresponding 110° in terms of the central angle of the color wheel 24 , red light is emitted by the on-state of the LED 21 , and is applied to the micromirror element 16 as shown by R-LED of FIG. 3C .
At this time, an image corresponding to the red light is displayed by the micromirror element 16 , whereby a red light figure is formed by the reflected light thereof, and is projected onto the external projection object through the projector lens unit 19 .
During this period, the oscillation of the semiconductor lasers 20 A, 20 B, 20 C is temporarily stopped. Accordingly, even when the blue light transmission diffusion plate 24 B or green fluorescent reflection plate 24 G of the color wheel 24 exists at the positions on the optical axis, the oscillation of the semiconductor lasers 20 A, 20 B, 20 C is temporarily stopped, and hence neither blue light nor green light is generated as the light-source light.
Thereafter, in synchronization with turning-off of the LED 21 , the oscillation at the semiconductor laser 20 A, 20 B, 20 C is resumed. After that, in a period of the G-field corresponding to 150° in terms or the central angle of the color wheel 24 , green reflected light excited at the green fluorescent reflection plate 24 G of the color wheel 24 is applied to the micromirror element 16 as the light-source light.
At this time, an image corresponding to the green light is displayed by the micromirror element 16 , whereby a green light figure is formed by the reflected light thereof, and is projected onto the external projection object through the projector lens unit 19 .
Furthermore, the color wheel 24 rotates to terminate the G-field and one-frame periods.
Thereafter, when the blue light transmission diffusion plate 24 B is positioned again on the optical axis from the semiconductor lasers 20 A, 20 B, 20 C in place of the green fluorescent reflection plate 24 G, the B-field period of the next frame is started.
As described above, the oscillation-timing and turning-on-timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and LED 21 are controlled in synchronization with the rotation of the color wheel 24 on which the blue light transmission diffusion plate 24 B and green fluorescent reflection plate 24 G are formed. As a result of this, the green and blue light resulting from the oscillation of the semiconductor lasers 20 A, 20 B, 20 C, and red light resulting from the on-state of the LED 21 are cyclically generated by time division, and are applied to the micromirror element 16 .
Furthermore, the R-field resulting from the on-state of the LED 21 is arranged in synchronization with the timing of the border between the blue light transmission diffusion plate 24 B, and green fluorescent reflection plate 24 G each constituting the color wheel 24 , and the emission timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and LED 21 is controlled as shown at the normal mode time, and green-emphasized mode time described above, whereby it is made possible to adjust the time length of each of the B-, R- and G-fields in the one frame period.
As described above, according to this embodiment, although the above-mentioned optical system is an optical system using a color wheel, it becomes possible to arbitrarily adjust the time length to be assigned to each color component, and respond to desired color environment such as color balance, brightness of the projection image, or the like, as needed.
Particularly, in the green-emphasized mode, the projection time of the green image based on the green light closer to the luminance component than the other primary color components is set longer. As a result of this, not only an image in which the green light is simply emphasized as a whole is obtained, but also the luminance of the overall image is improved, and a brighter image is projected.
It should be noted that in the above embodiment, as a light source configured to generate blue and green light by using a color wheel 24 , semiconductor lasers 20 A, 20 B, 20 C are used, whereby it becomes possible to realize a stable operation particularly excellent in response speed and light intensity. Furthermore, it is possible to enhance the marketability by using an element more suitable for the light source of the data projector apparatus.
In addition to the above, with the fluorescent substance practically used at present, the efficiency of the wavelength conversion of converting the blue laser light to red laser light is low, and sufficient emission luminance cannot be obtained. Thus, by using a red LED as the second light source element, and making it possible to adjust the period of each of the primary color image fields as described above, it becomes possible to realize projection-display of the red image having sufficient emission luminance.
(Another Operation Example)
Next, another operation example according to this embodiment will also be described below.
In this operation example too, it is assumed that as shown in FIG. 4A , while a blue light transmission diffusion plate 24 B constituting a color wheel 24 is arranged on a part of the circumference having a central angle of about 150° at position of 0° to about 150° in the rotational phase corresponding to the image frame, a green fluorescent reflection plate 24 G is arranged on a part of the circumference having a central angle of about 210° at a position of about 150 to 360° (0°) in the same rotational phase.
Here, it is also assumed that it is possible to switch the mode between the normal mode and luminance-emphasized mode as two color modes.
In the normal mode, the continued time ratio of periods in which the primary color images of blue, red, and green constituting one frame of the color image to be projected are projected is made 1:1:1.
That is, the continued time ratio b:r:g of the B-, R- and G-fields becomes 120°:120°:120° in terms of the central angles of the color wheel 24 with respect to 360° corresponding to one rotation of the color wheel 24 rotating at a constant rotational speed.
In the luminance-emphasized mode on the other side, in addition to the primary color images of blue, red, and green constituting one frame of the color image, an image of yellow is also projected. The continued time ratio of periods in which the primary color images of blue, red, green, and yellow are projected is made 1:1:1:1.
The period in which the primary color image of yellow is projected is defined as a Y-field.
That is, the continued time ratio b:r:g:y of the B-, R-, G- and Y-fields becomes 90°:90°:90°:90° in terms of the central angles of the color wheel 24 with respect to 360° corresponding to one rotation of the color wheel 24 rotating at a constant rotational speed.
All the operation control concomitant with the switching of the color mode is executed by a projection light processing section 31 under the centralized control of a CPU 32 .
FIG. 4B shows the relationship among the color of the light figure formed at the micromirror element 16 at the normal mode time, emission timing of the LED 21 , emission timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and output of the color wheel 24 .
At this normal mode time, at the beginning of one frame, in the period of the B-field corresponding to 120° in terms of the central angle of the color wheel 24 , blue light is emitted by the oscillation of the semiconductor lasers 20 A, 20 B, 20 C as shown by the CW output of FIG. 4B . Further, the blue light transmitted through the blue light transmission diffusion plate 24 B of the color wheel 24 , and diffused is applied to the micromirror element 16 .
At this time, an image corresponding to the blue light is displayed by the micromirror element 16 , whereby a blue light figure is formed by the reflected light thereof, and is projected onto an external projection object through the projector lens unit 19 . During this period, the LED 21 is kept in the off-state.
Thereafter, the on-state of the LED 21 is started in synchronization with a temporary stop of the oscillation of the semiconductor lasers 20 A, 20 B, 20 C. After that, in the period of the R-field corresponding to 120° in terms of the central angle of the color wheel 24 , red light is emitted by the on-state of the LED 21 , and is applied to the micromirror element 16 as shown by R-LED of FIG. 4B .
At this time, an image corresponding to the red light is displayed by the micromirror element 16 , whereby a red light figure is formed by the reflected light thereof, and is projected onto the external projection object through the projector lens unit 19 .
During this period, the oscillation of the semiconductor lasers 20 A, 20 B, 20 C is temporarily stopped. Accordingly, even when the blue light transmission diffusion plate 24 B or green fluorescent reflection plate 24 G of the color wheel 24 exists at the position on the optical axis, the oscillation of the semiconductor lasers 20 A, 20 B, 20 C is temporarily stopped, and hence neither blue light nor green light is generated as the light-source light.
Thereafter, in synchronization with turning-off of the LED 21 , the oscillation at the semiconductor laser 20 A, 20 B, 20 C is resumed. After that, in a period of the G-field corresponding to 120° in terms of the central angle of the color wheel 24 , green reflected light excited at the green fluorescent reflection plate 24 G of the color wheel 24 is applied to the micromirror element 16 as the light-source light.
At this time, an image corresponding to the green light is displayed by the micromirror element 16 , whereby a green light figure is formed by the reflected light thereof, and is projected onto the external projection object through the projector lens unit 19 .
Furthermore, the color wheel 24 rotates to terminate the G-field and one-frame periods.
Thereafter, when the blue light transmission diffusion plate 24 B is positioned again on the optical axis from the semiconductor lasers 20 A, 20 B, 20 C in place of the green fluorescent reflection plate 24 G, the B-field period of the next frame is started.
As described above, the oscillation-timing and turning-on-timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and LED 21 are controlled in synchronization with the rotation of the color wheel 24 on which the blue light transmission diffusion plate 24 B and green fluorescent reflection plate 24 G are formed. As a result of this, the green and blue light resulting from the oscillation of the semiconductor lasers 20 A, 20 B, 20 C, and red light resulting from the on-state of the LED 21 are cyclically generated by time division, and are applied to the micromirror element 16 .
Next, an operation at the luminance-emphasized mode time will be described below.
FIG. 4C shows the relationship among the color of the light figure formed at the micromirror element 16 at the luminance-emphasized mode time, emission timing of the LED 21 , emission timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and output of the color wheel 24 .
At this luminance-emphasized mode time, at the beginning of one frame, in the period of the B-field corresponding to 90° in terms of the central angle of the color wheel 24 , blue light is emitted by the oscillation of the semiconductor lasers 20 A, 20 B, 20 C as shown by the CW output of FIG. 4C . Further, the blue light transmitted through the blue light transmission diffusion plate 24 B of the color wheel 24 , and diffused is applied to the micromirror element 16 .
At this time, an image corresponding to the blue light is displayed by the micromirror element 16 , whereby a blue light figure is formed by the reflected light thereof, and is projected onto an external projection object through the projector lens unit 19 . During this period, the LED 21 is kept in the off-state.
Thereafter, the on-state of the LED 21 is started in synchronization with a temporary stop of the oscillation of the semiconductor lasers 20 A, 20 B, 20 C. After that, in the period of the R-field corresponding 90° in terms of the central angle of the color wheel 24 , red light is emitted by the on-state of the LED 21 , and is applied to the micromirror element 16 as shown by R-LED of FIG. 4C .
At this time, an image corresponding to the red light is displayed by the micromirror element 16 , whereby a red light figure is formed by the reflected light thereof, and is projected onto the external projection object through the projector lens unit 19 .
During this period, the oscillation of the semiconductor lasers 20 A, 20 B, 20 C is temporarily stopped. Accordingly, even when the blue light transmission diffusion plate 24 B or green fluorescent reflection plate 24 G of the color wheel 24 exists at the position on the optical axis, the oscillation of the semiconductor lasers 20 A, 20 B, 20 C is temporarily stopped, and hence neither blue light nor green light is generated as the light-source light.
Thereafter, in synchronization with turning-off of the LED 21 , the oscillation at the semiconductor laser 20 A, 20 B, 20 C is resumed. After that, in a period of the G-field corresponding to 90° in terms of the central angle of the color wheel 24 , green reflected light excited at the green fluorescent reflection plate 24 G of the color wheel 24 is applied to the micromirror element 16 as the light-source light.
At this time, an image corresponding to the green light is displayed by the micromirror element 16 , whereby a green light figure is formed by the reflected light thereof, and is projected onto the external projection object through the projector lens unit 19 .
Furthermore, the color wheel 24 rotates to terminate the G-field. Thereafter, the on-state of the LED 21 is further started without subsequently stopping the oscillation of the semiconductor lasers 20 A, 20 B, 20 C. After that, in the Y-field period corresponding to 90° in terms of the central angle of the color wheel 24 , red light is emitted by the on-state of the LED 21 as shown by R-LED of FIG. 4C .
Accordingly, yellow light resulting from the color mixture of the red light based on the on-state of the LED 21 , and green light based on the reflection at the green fluorescent reflection plate 24 G is applied to the micromirror element 16 .
At this time, an image corresponding to the yellow color is displayed by the micromirror element 16 , whereby a yellow light figure is formed by the reflected light thereof, and is projected onto the external projection object through the projector lens unit 19 .
Furthermore, the color wheel 24 rotates to terminate the Y-field and one frame periods. Thereafter, when the blue light transmission diffusion plate 24 B is positioned again on the optical axis from the semiconductor lasers 20 A, 20 B, 20 C in place of the green fluorescent reflection plate 24 G, the B-field period of the next frame is started.
As described above, the oscillation-timing and turning-on-timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and LED 21 are controlled in synchronization with the rotation of the color wheel 24 on which the blue light transmission diffusion plate 24 B and green fluorescent reflection plate 24 G are formed. As a result of this, the green and blue light resulting from the oscillation of the semiconductor lasers 20 A, 20 B, 20 C, red light resulting from the on-state of the LED 21 , and yellow light resulting from the color mixture are cyclically generated by time division, and are applied to the micromirror element 16 .
Furthermore, the R-field resulting from the on-state of the LED 21 is arranged in synchronization with the timing of the border between the blue light transmission diffusion plate 24 B, and green fluorescent reflection plate 24 G each constituting the color wheel 24 , and the emission timing of each of the semiconductor lasers 20 A, 20 B, 20 C, and LED 21 is controlled as shown at the normal mode time, and luminance-emphasized mode time described above, whereby it is made possible to adjust the time length of each of the B-, R-, G- and Y-fields provided as the need arises all of which are in the one frame period.
As a result of this, in this operation example too, it becomes possible to respond to desired color environment such as color balance, brightness of the projection image, or the like, as needed.
Particularly, in the luminance-emphasized mode shown in another operation example described above, the projection time of the yellow image based on the yellow color closer to the luminance component owing to the color mixture of the green and red light than the other primary color components each of which singly uses each light source is newly provided, and hence it is possible to significantly improve the luminance of the overall image, and project a bright image.
It should be noted that although not shown in the above operation example, a period may be provided in which red light based on the LED 21 is emitted simultaneously with the timing at which the blue light transmission diffusion plate 24 B of the color wheel 24 is present on the light path from the semiconductor lasers 20 A, 20 B, 20 C, magenta light is generated by the color mixture, and a corresponding light figure is formed.
Further, when attention is paid to the turning-on period of the LED 21 shown by R-LED of FIG. 4C , the on-state and off-state of the LED 21 are provided in two cycles for the two fields including the R- and Y-fields in each of which the on-state of the LED 21 is required in one frame.
By increasing the drive frequency of the LED 21 , and shortening the continuous on-time as described above, it is possible to maintain emission drive at stable and high luminance while taking the characteristics of the LED 21 that the emission luminance is lowered by the thermal resistance due to continuous drive into consideration.
It should be noted that the above embodiment has been described on the assumption that while the blue laser light is oscillated by the semiconductor lasers 20 A, 20 B, 20 C, and the blue and green light are generated by the color wheel, the red light is emitted from the LED 21 . However, the present invention is not limited to this and, for example, the LED 21 may be changed to a semiconductor laser configured to oscillate red laser light. In this case, it becomes necessary to provide a diffusion plate configured to diffuse red laser light to generate red light at a position on the optical axis of the semiconductor laser configured to oscillate the red laser light.
That is, when the luminance balance of primary color light which can be emitted by using one light source is not suitable for practical use, the present invention can be applied to a light source section in which a plurality of types of light sources are used to compensate the above drawback by using another light source, and a projection apparatus using such a light source section.
Further, in the above embodiment, the case where the present invention is applied to a data projector apparatus of the DIP (registered trademark) system has been described. However, the present invention can also be applied to a liquid crystal projector or the like configured to form a light figure by using a transmission type monochrome liquid crystal panel in the same manner.
Furthermore, the present invention is not limited to the embodiment described above, and can be variously modified in the implementation stage within the scope not deviating from the gist of the invention. Further, the functions carried out in the above-mentioned embodiment may be appropriately combined with each other to the utmost extent to be implemented. Various stages are included in the above-mentioned embodiment, and by appropriately combining a plurality of disclosed constituent elements with each other, various inventions can be extracted. For example, even when some constituent elements are deleted from all the constituent elements shown in the embodiment, if an advantage can be obtained, the configuration from which the constituent elements are deleted can be extracted as an invention.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | There is provided a light source device including a first light source configured to emit light in a first wavelength band, a light-source light generation section configured to generate light of each of a plurality of colors by time division by using the first light source, a second light source configured to generate light of a second wavelength band different from the first wavelength band, and a light source control section configured to cause each of the light-source light generation section and the second light source to generate light in one period, and to control a drive timing of each of the first and second light sources to adjust a light-emission timing and a light-emission period of light generated by each of the light-source light generation section and the second light source. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a chromakey method for inserting a background picture signal into key color-characterized key regions of a foreground picture signal, in which method fading operations are performed between the picture signals in proportional zones in dependence upon a control signal, while intermediate colors occurring in the proportional zones in the foreground signal are transformed into new intermediate colors which constitute a transition from the color of the foreground picture signal to that of the background signal.
2. Description of the Related Art
Such a chromakey method, in which there is a soft fading between the foreground picture signal and the background picture signal, and conversely, in a proportional zone, is proposed in the non-prepublished prior German Patent Application DE-A 41 42 650. At the transition of the actual picture contents and its colors to the key region and the color in that region, transition colors occur in the foreground picture signal, which transition colors become disturbingly manifest when there is an abrupt change-over from the foreground signal to the background signal. In accordance with the above-mentioned prior Patent Application, there should be a soft fading between the foreground picture signal and the background picture signal, while these transition colors should be transformed. In the transformation of the transition colors, an orientation with respect to the colors of the background picture signal-is realized so that the transition colors, no longer vary between the color of the foreground picture signal and the key color, but between the color of the foreground picture signal and the color of the background picture signal.
However, the problem of this method is that this proportional zone can only be fixed jointly for all foreground colors. Moreover, these colors may vary through several pictures/sub-pictures so that under circumstances, a proportional zone once fixed is no longer optimal. A correction could be performed by manually correcting the control signal which controls the fading in the proportional zone.
SUMMARY OF THE INVENTION
It is an object of the invention to further develop the method described in the opening paragraph in such a way that it can be better adjusted, both locally and with respect to time, to the data in the picture.
According to the invention, this object is solved in that individual proportional zones for regions of different color locations in the foreground picture signal are fixed in such a way that a distance between the color location of each region and a color location of the key color is determined individually for each region, and in that the control signal is generated for each region in dependence upon the color location distance determined for the respective region.
Thus, a suitable proportional zone is determined individually for each region of a given color location or color location range in the foreground picture signal. To this end, the distance between the color location of the foreground picture signal region and the color location of the key color is determined. In accordance with this distance, the proportional zone and hence the control signal controlling the transition in this zone can be adapted to this distance. The control signal is thus individually generated in dependence upon the fixed distance for each of these foreground picture signal regions. For color locations in the foreground picture signal, which are relatively fax remote from the color location of the key signal, a relatively wide proportional zone may be chosen by generating the control signal accordingly, whereas a short proportional zone may be chosen for regions whose color locations are relatively close to those of the key signal. Thus, the proportional zone is individually adapted to an optimal extent to the color location of the respective region.
An independent and very rapid adaptation to the picture data is realized. The length of the transformation range is adapted to the distance between the color location of the respective range of the foreground picture signal and the color location of the key signal. Consequently, color transitions from the foreground picture signal, which, with respect to their color location, are very close to the key signal, are also faded without any fringes, likewise as those whose color location is relatively fax remote from the color location of the key signal. During the fading operation, there is thus a natural color transition from the foreground picture signal to the background picture signal, and conversely, with the correct intermediate hues.
In accordance with an embodiment of the invention, the respective color location distance is determined for regions of different color locations in a picture line of the foreground picture signal, and the control signal for the proportional zones of the regions of said picture line is generated in dependence upon said distance, and in that the control signal is subsequently used in the buffered foreground picture signal for the fading operations in the proportional zones of said picture line.
The individual determination of the color locations for foreground picture signal regions may advantageously be effected line by line. Thus, in one picture line of the foreground picture signal, it is determined which regions of different color locations of the foreground picture signal are present and which respective color location distance is present between these regions and the color location of the key signal. The control signal for the proportional zones can be individually generated for the different regions of these picture lines. The control signal thus generated may subsequently be used for the corresponding fading operations and for the resultant transformation of the intermediate colors in that the foreground picture signal is delayed by one picture line so that the control signal for this delayed picture line is available at the correct time.
In accordance with a further embodiment of the invention, the control signal K is generated in accordance with the formula ##EQU1## in which L x is the distance between the color location of a foreground picture signal region and the color location KC x of the key signal, and in which L is the distance between the color location in question of a transition color occurring in the proportional zone and the color location of the key color.
For the above-described regions of different color locations in the foreground picture signal, an individual value of L x is determined which represents the distance between the color location of the foreground picture signal region and the color location of the key signal. Transition colors occur in the foreground picture signal in the color location range between the color location of a foreground picture signal region and the color location of the key signal. In this range, different transition colors have different distances to the color location of the key color. The distance in question is designated by means of the value L. The formula given above yields a value K at a known value of L x and at the value L to be determined at the time in the transition range. This value K represents the control signal which indicates to which extent the fading operation from the foreground picture signal to the background picture signal, or conversely, is to be performed and which thus also controls the color transformation.
The extreme values are K=0, i.e. only the foreground picture signal is inserted, or K=1, i.e. only the background picture signal is inserted. In the transition range the value K of the control signal assumes values between 0 and 1 so that a soft fading and a transformation of the transition colors takes place. This transition range between the values 0 and 1 of the value K of the control signal represents the proportional zone. Values of K<0 or K>1 are not admissible and are limited to 0 or 1, respectively.
The transformation of the transition colors in the proportional zone may be performed in accordance with the formula
OUT=FG+K×(BG-KC)
in which FG is the current color of the foreground picture signal, BG is the current color of the background picture signal, and KC is the key color. All these signals may be present either as components R, G, B, or as luminance and color difference signals Y, C B and C R . Dependent on the control signal, i.e. the value K, there is a transformation of the transition colors during the fading operation.
To ensure that the value K is always 0 for a region of a given color location or color location range, a further embodiment of the invention is characterized in that for small spreads in the color locations within a region, a minimum distance between said color locations and the color location of the key color is chosen for L x . This ensures that, with small spreads of the color locations of a region always occurring, no part of this region is keyed out.
In a further embodiment of the invention, a value of L xmin is chosen for the foreground picture signal regions whose color location is proximate to the color location of the key signal, and in that L x is set at L xmin for computing the control signal for regions where L x <L xmin .
A value L xmin may be given which is always assumed for such regions as value L x whose color location is close to that of the key color and for which a value of L x is found which is smaller than L xmin . The value L xmin may also be used to enforce a value K=0 of the control signal in arbitrary regions of the foreground picture signal.
In accordance with a further embodiment of the invention, the color locations KC are determined individually for different regions of the key signal. Also the color and thus the color location of the key signal may change to a small extent. By individually determining the color location, for example, for different regions within a picture line of the foreground picture signal, the proportional zone can be determined even more accurately, because the value K of the control signal is then determined in accordance with the above-given formula in dependence upon the actual color locations of the key signal. The determination of the distances required for the determination of the values of the control signal K then relate to the, actually present color location of the key signal, which, as stated, may have a small spread.
In accordance with the limit value L xmin for color locations of the foreground picture signal region, a limit value KC xmax may be provided for the smallspread color locations of the key color, which value, in a further embodiment of the invention, is chosen in such a way that a limit value KC xmax is chosen, below which value the color locations KC constantly track the changing color location of the key color.
In a further embodiment of the invention, the values L xmin and KC xmax can be chosen in dependence upon an angle in the color space for an even better adaptation to the different color locations occurring in the foreground picture signal.
A further embodiment of the invention is characterized in that in determining the color location distance between the foreground picture signal region and the key color region, an angle corresponding to this distance is also determined in the color space.
This determined angle may be used, for example, for correcting the angle deviations during the edge, which deviations are caused by gamma precorrection of a camera signal.
A further embodiment of the invention is characterized in that for determining the values of L x and possibly KC x , the first and second derivatives of the function L(t), indicating the variation with respect to time of the distance between the color location of a pixel of the foreground picture signal and the color location of the key signal, are used for determining saddle points in the variation of the function L(t) in such a way that the first and second derivatives of L of T have the value of zero, while for edges in the transition between a color region of the foreground picture signal and a key color region, it holds that the last saddle point before falling below the value L xmin is the value L x of the color region of the foreground picture signal, and that the first saddle point after falling below the value KC xmax is the value KC x of the key color region, and for edges in the transition between a key color and a color region of the foreground picture signal, it holds that the last saddle before exceeding the value KC xmax is the value KC x of the key color region, and that the first saddle after exceeding the value L xmin is the value L x of the color region of the foreground picture signal, while it holds for all edges that the values of L x and KC x determined at the two relevant saddle points are only valid when there is no further saddle point between the two relevant saddle points.
For determining the respective value K of the control signal in accordance with the above-given formula, the value L x of a foreground picture signal region must be determined. If the color locations of the key signal are also determined individually, the value KC x of a region of the key area should also be determined. For determining these values, the curve analysis of the algebraic differential calculus can be advantageously utilized in that the first and the second derivative of the function L(t) are formed. This may be effected, for example, by subtraction of successive values.
The values L x and KC x substantially represent the values constituted by the base and the head, respectively, of an edge. In accordance with the algebraic curve analysis, these points represent saddle points in the variation of the function L(t). These saddle points are characterized in that the first and second derivative of the function L(t) have the value 0. Moreover, if the boundary condition is used, stating that only those individually determined values of L x are valid which are larger than L xmin and only those individually determined values of KC x are valid which are smaller than KC xmax , the additional condition applies that these saddle points should be correspondingly arranged above or below the values L xmin and KC xmax , respectively. The condition then holds that there should be no further saddle point between the two saddle points marking the start and the end of a transition edge, because this indicates that there is no smooth transition from or to the key color and that no appropriate L x can be determined. In this case the value L xmin is assumed for L x and the value KC xmax is fixed for KC x .
The values K of the control signal and the distance and limit values required therefor can be relatively easily computed by means of signal processors. To this end a further embodiment of the invention is characterized in that an arrangement for performing the method according to the invention is provided which comprises a memory for delaying the picture signal by approximately one picture line, a digital signal processor with a memory for determining the values L xmin , KC xmax and a mean value of the color locations KC of the key colors, and in that one or more further processors are provided for determining the individual values of L x and KC x which in their turn are used for determining the control signal K.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings;
FIGS. 1a and 1b show, as a function of time, the signal L(t) and the values L x and KC x and their limit values L xmin and KC xmin for one picture line;
FIG. 2 shows the occurring color locations of the signal of FIGS. 1a and 1b,
FIGS. 3a and 3b show an example for angle-dependent choice of the value KC xmax ;
FIG. 4 is a representation, similar to that in FIGS. 1a and 1b, of another picture content of the foreground picture signal; and
FIG. 5 shows a block diagram of an arrangement for performing the method.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1a and 1b show the signal L(t) as a function of time for one picture line. The signal L(t) indicates the color location distance between the color location occurring in the foreground picture signal and the color location of the key color.
In accordance with the inventive method, the control signal and its value K should be determined in such a way that an optimal transition between the foreground picture signal and the background picture signal (not shown in the Figure) is achieved for the respective transition ranges and the transformation of the intermediate colors to be performed in these ranges. In FIGS. 1a and 1b, these transition ranges are those ranges in which a foreground picture signal region adjoins a key color region. These regions are characterized in that relatively steep edges occur in these regions in the function L(t). According to the invention, these edges are determined and the bases and heads of these edges are utilized for determining the values L x and KC x .
Respective limit values, denoted by L xmin and KC xmax , may be provided for the values L x to be individually determined for each region and, possibly for the values KC x to be individually determined for the key ranges. L xmin indicates the limit from which the individually determined values of L x are taken into account. If a region has a value L x which is smaller than the value L xmin , the intermediate colors are transformed and the value L xmin is used for this region. The value KC xmax indicates an upper limit from which the occurring color locations are no longer considered to be associated with the spread of the key color.
A small region which is to be associated with a first color location distance L x1 occurs at the start of a picture line shown in FIG. 1a. Subsequently, a region of the key color occurs. This is followed by a relatively large region of the foreground picture signal which has a color location distance L x2 at the start and a color location distance L x3 (similar to L x2 ) at the end. A further region with a color location distance L x4 follows after a short region of the key color.
To determine the values L x of the different regions, the algebraic curve analysis is used which allows the determination of the heads and bases of the respective transitions. FIG. 1a shows, below the picture line, the respective saddle points determined in the curve analysis. A saddle point is present whenever both the first and the second derivative of the signal L(t) are simultaneously zero.
At the transition between the first foreground picture signal region and the first key region in FIG. 1a, a saddle point occurs at the start of the edge and a saddle point occurs at the end of the edge. These two saddle points mark the value L x1 of the foreground picture signal region and the value KC x of the key signal region. The condition holds that the first saddle point marking the value L x1 of the foreground picture signal region is the last saddle point before falling below the value L xmin , and that the value KC x1 is the first saddle point after falling below the value KC xmax . The boundary condition further holds that no further saddle point may occur between these two saddle points.
In a corresponding manner, it is determined for the subsequent rising edge representing a transition from the key signal region to another foreground picture signal region, that the last saddle point occurring before exceeding the value KC xmax marks the value KC x2 of the key region, and that the next saddle point occurring after exceeding the value L xmin marks the value L x2 of the foreground picture signal region.
In the further variation with respect to time in accordance with FIG. 1a, a transition occurs again between the region for which the value L x2 was determined and a key region. The two corresponding saddle points are marked in the drawing. For the subsequent transition from the key region to another region for which the value L x4 is determined, the corresponding saddle points are also marked. At this transition, for example, the value L x1 is determined, which is marked by the first saddle point after exceeding the value L xmin .
The control signal K can be determined with reference to the now known values of L x1 to L x2 and the several values KC x for the key regions during the period of the edge, in accordance with the formula ##EQU2##
In the ranges of the edges shown in FIG. 1a there is a fading to a background picture signal (not shown in FIGS. 1a and 1b) with reference to this control signal. In the proportional zones, a transformation of the occurring transition colors is performed in so far as the value L x of a foreground picture signal region is above the value L xmin .
The same formula for determining the control signal K is used in the key color regions between a failing and a rising edge. L x is replaced by L xmin again so that for each relatively small L x of the key color region, a value of approximately 1 results for the value K of the control signal. In the foreground color regions between a rising and a falling edge, the substitution value L xmin in the same formula may also be used because a value K=1 of the control signal is to be secured in this case.
FIG. 1b shows the variation with respect to time of the values L x and KC x for the picture lines of FIG. 1a. FIG. 1b also shows at which instants the values L x1 to L x4 and KC x1 to KC x4 are determined and in which ranges they are valid. Moreover, the limit value L xmin is shown for the signal L x .
FIG. 2 shows two graphs of the Cb/Cr color space. The two graphs show the color locations occurring during the picture line shown in FIGS. 1a and 1b. FIG. 2 shows that some accumulations of color locations occur. One color location accumulation corresponds to the first small region and the last large region of the representation according to FIGS. 1a and 1b. For these two regions, the color location distance L x1 was determined, which, as is visible in FIG. 2, is larger than the limit value L xmin .
For the first large region occurring in the picture line shown in FIGS. 1a and 1b, the value L x2 was determined which represents the small spread of color locations of this region approximately in its low limit value. This is visible in the second representation according to FIG. 2.
In the two representations according to FIG. 2, the small spreads of color locations KC x of the key region are shown, as well as the limit value KC xmax . The value L(t) of the representation according to FIGS. 1a and 1b, substantially represents the value of the distance constantly changing in the course of a picture line between the actually occurring color location and a nominal color location of the key region KC x .
In the representation according to FIG. 2, the limit values L xmin and KC xmax are chosen in the form of circles. To adapt these limit values even better to different other color locations occurring in the foreground picture signal, it is advantageous to choose the two limit values in dependence upon the angle. This is shown in FIGS. 3a and 3b by way of example. FIG. 3a shows three different limits L xminL , L xminO and L xminR and, for example, all these limits can be manually adjusted independently of each other.
In this way, a different fundamental selectivity may be created for different colors of the foreground picture signal. FIG. 3b shows that the corresponding limits for KC x can similarly be chosen in dependence upon the angle. The limit angles will generally be close together at KC x because the range of spread of the KC color locations normally extends essentially radially (saturation), which is conditioned by shadows forming on the color wall.
FIG. 4 shows the variation with respect to time of the function L(t) similar to FIGS. 1a and 1b, but for a different picture line with a different picture content. In FIG. 4 too, a small region initially occurs which is followed by a key color region. Subsequently, a foreground picture signal region with a relatively large value L(t) follows. This region is followed by a key color region again. For these mentioned regions, there are no particular problems when determining the values L x and KC xmax ; the determination is performed with reference to the saddle points in conformity with the picture line shown in FIGS. 1a and 1b. A saddle point representing the base of the next edge is present again at the end of the second key color region. However, after this saddle point, several further saddle points follow before the value L xmin is exceeded. This no longer satisfies the above-mentioned condition that the saddle points above L xmin and below KC xmax only mark a base and a head of an edge when no further saddle point occurs between the two saddle points. This condition is no longer fulfilled in the case of the second rising edge in FIG. 4 so that no value L x is determined for the relatively large region of this picture line. In this case the value L xmin is chosen for the value L x , and a transformation of the intermediate colors, using L xmin , is performed for the fading range between the background signal, which is used in the key color region, and the foreground signal.
FIG. 5 shows a block diagram of an arrangement for performing the method. The arrangement receives a luminance/chrominance signal LUM/CHR which is delayed in a memory 1 by one picture line period. A time code is generated in a time code generator 2 in addition to this signal LUM/CHR, which time code is also stored in the memory 1. Both the time code and the associated signal LUM/CHR are further applied to a reference processor 3.
The arrangement also includes a control unit 4 which controls a digital signal processor 5 which is connected to a memory 6. Particularly, the limit values L xmin and KC xmax can be predetermined by means of the control unit 4 and the digital signal processor 5. These values are also applied to the reference processor 3 which, with reference to these values, as well as to the chrominance signal CHR applied thereto, constantly computes the values L(t) and, with reference to these values, can compute the values L(x) and KC(x). These values are applied to a further processor 7 which computes the control signal K with reference to these values.
With reference to the control signal K and by means of a mixing device, which is not shown in FIG. 5, the foreground picture signal delayed by one picture line in the memory 1 can be faded to a background picture signal, which is not shown in FIG. 5, or, conversely, faded from the background picture signal to the foreground picture signal. | In a chroma-key method for inserting a background picture signal into key color-characterized key regions of a foreground picture signal, in which method fading operations are performed between the picture signals in proportional zones in dependence upon a control signal, while intermediate colors occurring in the proportional zones in the foreground signal are transformed into new intermediate colors which constitute a transition from the color of the foreground picture signal to that of the background signal, an optimal adaptation of the proportional zone to the respective color location of a foreground picture signal region is ensured in that individual proportional zones for regions of different color locations in the foreground picture signal are fixed in such a way that the distance between the color location of each region and the color location of the key color is determined individually for each region, and in that the control signal is generated for each region in dependence upon the color location distance determined for the respective region. | 7 |
FIELD OF THE INVENTION
This invention relates to bicycles. More particularly, this invention relates to techniques and devices for use in holding or retaining the drive chain on a bicycle while removing the rear wheel.
BACKGROUND OF THE INVENTION
When the rear wheel of a conventional bicycle is removed (e.g., in order to change a tube or the tire itself), the drive chain must be removed from the drive sprocket. Typically the chain is dirty and greasy. Thus, one must ordinarily handle the chain both when removing the rear wheel and then again when installing the rear wheel on the bicycle after it has been repaired.
Aside from the fact that the chain may be dirty and greasy, the task of removing and replacing the rear wheel requires one to properly position the chain so that it properly engages the drive sprocket when the rear wheel is replaced. Also, when the rear wheel is removed from the bicycle, the chain may fall to the ground or become entangled. This is very undesirable. In general the handling of the chain when removing or installing the rear wheel is rather cumbersome and difficult.
This problem was addressed in U.S. Pat. No. 3,840,251 where there is described a bracket device which conforms to the periphery of the chain sprocket. The device includes an edge or flange which is perpendicular to the axle. By manipulation of the device, the chain is said to be supported by the device when the rear wheel is removed from the bicycle. The intended use of the bracket requires that it be properly manipulated to first engage the chain and then to disengage the chain when the rear wheel is installed on the bicycle again. It is very doubtful that such bracket device would be effective in engaging the chain and removing it from the sprocket because engagement of the chain on the rear side of the sprocket (centrally of the engagement arc) as the wheel is dropped will cause the chain to engage the sides of the sprocket very tightly. This binding would prevent the removal of the rear sprocket from the frame. It would be possible to remove the rear sprocket and then manually lift the chain off the sprocket and hang it on the bracket device, but that would be very cumbersome.
Another type of device is described in U.S. Pat. No. 4,509,767, where the device is referred to as chain hanger comprising an elongated body having a driving head and a drill bit on opposite ends. The device is installed on the bicycle seat stay above the rear wheel sprocket. When it is desired to remove the rear wheel from the bicycle frame, the chain must be manually lifted upwardly and placed onto the device. Thus, it is necessary to handle the chain to lift it onto and off of the device when removing the rear wheel and then installing the wheel again. Also, the chain must be forced out of line laterally in order to force the chain around the end of the hanger.
Various chain holding and locking devices are described in U.S. Pat. Nos. 2,165,377; 3,132,878; and 2,636,717. However, none of such patents describe or suggest devices or techniques which would be suitable for use on bicycles to support a drive chain.
There has not heretofore been provided a chain hanger device which is simple and effective for retaining and supporting a bicycle chain when removing the rear wheel of a bicycle.
SUMMARY OF THE PRESENT INVENTION
In accordance with one embodiment of the present invention there is provided a device for attachment to the horizontal chainstay tube of a bicycle. The device is attached to the tube just forwardly of the chain sprocket. The device includes a ledge projecting generally horizontally away from the tube and generally perpendicular (in a horizontal plane) to the line of the drive chain.
When the rear wheel of the bicycle is removed from the frame, the upper portion of the chain loop is allowed to rest upon the ledge where it is safely and effectively supported. The chain engages the ledge without any need for manually grasping the chain. When the rear wheel is installed on the frame again, the chain is engaged by the drive sprocket and is easily lifted off the ledge, without having to manually grasp the chain.
Thus, the device of this invention is stationary on the frame of the bicycle and does not require any special manipulation or adjustment in order to engage or disengage the drive chain during removal of the rear wheel or subsequent installation thereof on the frame.
In a preferred embodiment the device of the invention comprises a horizontally disposed ledge portion and attachment means for attaching the device to the horizontal chainstay tube of a bicycle. The ledge portion projects away from the tube in the direction of the chain. The outer end of the ledge includes an upwardly projecting lip.
When the rear wheel of the bicycle is removed from the frame, the drive chain comes into contact with the ledge and is supported there. This prevents the chain from falling to the ground and becoming entangled. Use of the device of the invention also avoids the need to grasp the chain and manipulate it to a particular position.
In another embodiment of this invention there is provided a hanger device which is secured to the drive side chainstay tube and dropout assembly of a bicycle frame. This device comprises an upwardly extending flange which preferably is angled away from the dropout assembly of the frame and toward the drive sprocket. The upper edge of the flange is very narrow. The flange may be tapered.
The outer edge of the flange intercepts the chain when the rear wheel of the bicycle is removed from the frame. When the chain is thus engaged, it is held and supported vertically by the hanger.
The hanger device of this invention contains no moving parts. It remains stationary on the frame at all times. It does not interfere in any way with the normal operation of the bicycle.
When transporting a bicycle, repairing or replacing a tube, or just working on a bicycle, it is frequently necessary to remove the rear wheel. Accordingly, the chain hanger devices of this invention are very useful on all bicycles.
Also, when competing in races, wheel exchanges are often necessary (due to flat tires or damage to the wheel). The time allotment for making changes is minimal. Consequently, the chain hanger devices of this invention are especially useful on racing bicycles also. No personal physical contact with the chain itself is required. Also, the chain does not drop to the ground or become entangled.
Another advantage of certain embodiments of the hanger devices of the invention is that they can be easily affixed to existing bicycle frames regardless of the size of frame tubes, gearing variations and derrailleur combinations, frame dimensions, etc. The hanger device can be easily installed and adjusted by the user without need for special tools or skills.
The hanger devices of this invention can also be installed on bicycle frames as original equipment, if desired. The hanger devices may be affixed to the frame, for example, by means of welding, brazing, riveting, adhesive bonding etc. The hanger device may even be cast as an integral part of the dropout assembly.
Other advantages of the hanger devices of this invention will be apparent from the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described in more detail hereinafter with reference to the accompanying drawings, wherein like reference characters refer to the same parts throughout the several and in which:
FIG. 1 is a perspective view illustrating one embodiment of a hanger device of the invention mounted on the horizontal chainstay tube of a bicycle frame;
FIG. 2 is a rear elevational view of the assembly of FIG. 1;
FIG. 3 is a perspective view of the hanger device shown in FIG. 1;
FIG. 4 illustrates operation of the hanger device when the rear wheel of the bicycle is removed from the frame;
FIG. 5 is a top view of another hanger device of the invention affixed to the horizontal chainstay tube of a bicycle frame;
FIG. 6 is a side elevational view of another embodiment of hanger device of this invention;
FIG. 7 is a rear elevational view of another embodiment of hanger device of this invention;
FIG. 8 is a side elevational view of a bicycle frame with the hanger device of FIG. 7 mounted thereon;
FIG. 9 is a side elevational view illustrating another embodiment of hanger device of this invention and also illustrating plural positions for hanger devices;
FIG. 10 is a rear elevational view showing the hanger device of FIG. 9;
FIG. 10A is a rear elevational view showing the manner in which the hanger device of FIG. 9 engages the chain when the rear wheel is removed from the dropout assembly;
FIG. 11 is a rear elevational view showing another embodiment of hanger device of the invention;
FIG. 12 is a side elevational view showing the manner in which the hanger device of FIG. 9 engages the chain when the rear wheel is removed;
FIG. 13 is a side elevational view illustrating a hanger device affixed to the dropout assembly of a bicycle frame; and
FIG. 14 is a side elevational view illustrating another embodiment of hanger device of the invention.
DETAILED DESCRIPTION OF THE INVENTION
In FIGS. 1-4 there is illustrated one embodiment of chain hanger device 5 of the invention. In FIGS. 1, 2 and 4 the device is shown attached to horizontal chainstay tube 14 of a bicycle frame. The frame seat stay is designated as 13.
The hanger device includes a generally horizontal ledge portion 5B which extends away from the horizontal chainstay tube 14 in the direction of the drive chain 10. The outer end of the ledge portion includes an upwardly projecting lip 5C. Flange 5D extends along tube 14 to assist in preventing the chain from scratching tube 14 when the rear wheel is removed. Although the ledge portion is illustrated as having a planar upper surface, this is not required. It may be curved (i.e., convex) if desired.
The device also includes attachment or mounting means for securing the device to the tube 14. In the embodiment shown in FIGS. 1-4 there is illustrated a flexible band 5A which is connected at one end of the body portion of the hanger device. The opposite end of the band 5A is able to be folded around the tube 14 and then brought through a slotted aperture 5F in the body portion. Preferably band 5A is composed of tough plastic (e.g., nylon).
A threaded screw 6 fits into the aperture 5F. Band 5A includes spaced slots or grooves 5E which are engaged by the threads of the screw 6. As the screw is rotated, the threads engage the grooves 5E and draw the band tightly around the tube 14. If desired, double-sided adhesive tape may be positioned on the tube 14 before the hanger 5 is attached. Because the band is adjustable, it will accommodate different diameters of chainstay tube 14.
When the sprocket 12 of the rear wheel of the bicycle is loosened and detached from the frame and dropped downwardly, the chain 10 is automatically caught and supported by the hanger device 5. This is shown in FIG. 4. Then the sprocket 12 can be disengaged from the chain.
The hanger device 5 fully supports the chain 10 vertically and laterally with the help of the idler sprocket 15A of the derrailleur assembly. Then when it is time to re-attach the rear wheel and sprocket to the frame, the chain is already in the proper position for re-engagement to the sprocket 12.
The hanger device 5 is positioned on tube 14 just forwardly of the position of the rear sprocket 12, as illustrated. The hanger device may be positioned farther forwardly on tube 14, if desired. For example, it may be positioned a few inches further away from the rear sprocket 12, although the preferred position is as illustrated in FIGS. 1 and 4.
FIG. 5 is a top view of another embodiment of hanger device 20 of the invention. This embodiment includes a generally flat ledge portion 20B having an upwardly projecting lip 20A on the outer end thereof. The device may be metal and is secured to tube 14 by means of screw 21 which extends through an aperture in the flange portion of the device and into an aperture in tube 14. Alternatively, the device may be secured to steel tubes by brazing or welding and to aluminum tubes by riveting or with epoxy adhesive. Dotted lines illustrate the position of the chain 10 when it is supported by the device 20. Because tube 14 is oriented at an angle of approximately 7° relative to the path of the drive chain, the ledge portion of the hanger is not exactly perpendicular to the tube 14 centerline.
FIG. 6 is a side elevational view of yet another embodiment of hanger device 30 of this invention secured to chainstay tube 14. The device includes a ledge portion 30A. Flange 30B extends from the body portion of the device along the tube 14 toward the rearward end of the tube. An elongated flange portion 30C extends forwardly along tube 14 to further protect the tube 14 from abrasion from the chain of the bicycle. The length of the flange portion 30C may vary, as desired.
FIGS. 7 and 8 illustrate yet another embodiment of hanger device 40 of this invention which comprises a band 42 for attachment of the device to horizontal chainstay tube 46. Suspended below band 42 is a hanger member 44 having a ledge portion 44B having an upstanding lip 44A on the outer end thereof. A bolt 45 secures the hanger 44 to band 42. If desired, the abutting faces of hanger 44 and band 42 may be serrated or grooved such that the angular position of hanger 44 relative to band 42 may be changed and then fixed in any desired position by tightening bolt 45.
The hanger device shown in FIGS. 7 and 8 is especially useful on bicycles which have an elevated chainstay. As shown in FIG. 8, the chainstay 46 is positioned above the point where the rear sprocket attaches to seat stay 47.
The dimensions of the hanger device of the invention may vary. Generally speaking, the length of the ledge portion is at least equal to the width of the drive chain and preferably is a few percent greater than the width of the chain. The length of the ledge portion may be as great as about 1.5 inches or more, if desired, so that it will catch the chain from any shifted position.
The hanger device may be made of various materials, although durable plastic (e.g., nylon, Delrin, etc.) may be preferred for retro-fitting the device onto existing bicycles. The hanger device may be mounted on the horizontal chainstay tube in a variety of manners. It may be attached to the tube at the factory at the time of original manufacture, or it may be attached later after purchase by the consumer.
Another embodiment of hanger device 50 of the invention is shown in FIGS. 9, 10 and 10A. In this embodiment the hanger device comprises a mounting portion 50A and an outwardly extending flange portion 50B. The outer edge 50B of the flange is tapered and is very thin. The mounting portion secures the hanger device to the dropout assembly portion 14A of frame 14 of the bicycle. For example, the device may be secured to the dropout assembly by welding, brazing, adhesive, etc. Preferably the hanger device is composed of metal.
The flange portion 50B extends towards the gear sprocket 12 in a manner such that the flange is very close to but not touching the sprocket. The purpose of the flange portion is to engage the chain 10 when the rear wheel is removed from the frame. This is illustrated in FIG. 10A. Preferably the device includes an upper button or raised portion 50C which serves to prevent the chain from falling completely into the area between the flange and the mounting portion 50A and binding there. The raised portion 50C also keeps the chain aligned far enough to the left on the flange so that the space between the rollers and plates of the chain can be engaged by the sprocket teeth.
Preferably the raised portion 50C extends outwardly to an extent such that at least half of the length of the roller 10A is to the left of the flange 50B (see FIG. 10A). Even more preferably, at least about 85% of the length of the roller is positioned to the left of the flange.
Preferably the flange 50B can be bent inwardly or outwardly at the time of installation to accommodate a particular sprocket. It is also preferable for button 50C to be adjustable in thickness.
As shown in FIG. 9, the preferred location for hanger device 50 is near the top of the dropout assembly 14A. The particular dropout assembly shown there includes a nearly vertical slot for receiving the axle 9. Axle clamp nut 11 is threaded on the end of the axle. The axle and sprocket 12 drop nearly straight downwardly (in the direction of the arrow) to be removed from the dropout assembly. The hanger device 50 engages the chain 10 when the sprocket and rear wheel are removed.
The hanger device may be located at other locations on the dropout assembly, if desired. For example, it may be located at position 52 which is forward of the position 50. It may also be located at position 51 which is further rearwardly on the dropout assembly. If desired, there may be a plurality of such hanger devices mounted to the dropout assembly. It is also possible to include a hanger device 5 of the type described in connection with FIGS. 1-4.
FIG. 11 illustrates another embodiment of hanger device 55 which is useful in this invention. This embodiment of hanger device includes a mounting bracket or clamp portion 55A. A bolt or screw 56 is used to secure the clamp portion to the dropout assembly. The device also includes a flange portion 55B which extends outwardly and upwardly toward the sprocket 12 so that it can engage the chain 10 when the sprocket is detached from the dropout assembly.
FIG. 12 illustrates the chain position on two hanger devices 50 which are secured to dropout assembly 14A at two separate locations. One location is at the upper portion of the dropout assembly and the other location is at the rear portion of the dropout assembly. The two hanger devices support and retain the chain in the position shown when the sprocket 12 is removed. The chain 10 remains trained around the two sprockets 15A and 15B of the derrailleur assembly. Spring tension on the assembly is adjusted by means of screw 16. The derrailleur assembly supports the chain and tensions it. The spring tension causes the idler assembly to be directly in the way of the sprocket and axle when the wheel is removed. Thus, the derrailleur assembly is pivoted rearwardly out of the path of the sprocket in order to remove the rear wheel, after which the derrailleur assembly is allowed to spring back and maintain chain alignment.
FIG. 13 illustrates another hanger device 60 of the invention which is brazed or welded to the dropout assembly 64. The device includes a mounting portion 60A and an outwardly flaring flange portion 60B. In this assembly the slot for receiving the axle is sloped forwardly.
FIG. 14 illustrates yet another embodiment of hanger device 70 on a dropout assembly 74. In this embodiment the mounting portion 70A is elongated, as is the flange portion 70B. The primary chain support portions are at opposite ends of the device. If desired, the flange could extend forwardly from its upper end in a generally-horizontal manner. It could even extend forwardly of the dropout assembly, if desired, as illustrated by the dotted lines in FIG. 14.
Other variants are possible without departing from the scope of this invention. The various embodiments of chain hanger devices described herein perform the same function, i.e., catching the chain when the rear drive wheel is removed from the frame and holding the chain in such alignment that the drive sprocket will re-engage the chain properly with no manipulation or handling of the chain when the wheel is replaced. The hanger device may be affixed to the horizontal chainstay tube slightly forwardly of the sprocket or it may be secured to the inside of the dropout assembly adjacent the sprocket. The hanger device is effective throughout a range of positions, as illustrated in the drawings. Once the chain is caught by the hanger device it is held and supported vertically and laterally. A combination of hanger devices may also be used, if desired. The types of materials used for the hanger devices may vary, depending upon the strength, hardness and durability desired. | Chain hanger devices are described for attachment to a bicycle frame for supporting and retaining the drive chain vertically and laterally when the rear wheel and drive sprocket are removed from the frame. The hanger devices engage the chain without requiring manual manipulation of the chain. The rear wheel can be inserted into the frame again without physically handling the chain. | 1 |
RELATED APPLICATIONS
This Application is a Continuation Application of U.S. patent application Ser. No. 12/882,941, filed Sep. 15, 2010, entitled “DIGITAL REPEATER HAVING BANDPASS FILTERING, ADAPTIVE PRE-EQUALIZATION AND SUPPRESSION OF NATURAL OSCILLATION”, which is a continuation application of U.S. patent application Ser. No. 10/495,144, filed Jan. 11, 2005, now Issued U.S. Pat. No. 7,809,047, issued Oct. 10, 2005, entitled “DIGITAL REPEATER HAVING BANDPASS FILTERING, ADAPTIVE PRE-EQUALIZATION AND SUPPRESSION OF NATURAL OSCILLATION”, which is a U. S. National Phase filing of PCT Application Publication No. WO 2003/043216, entitled “DIGITAL REPEATER HAVING BANDPASS FILTERING, ADAPTIVE PRE-EQUALIZATION AND SUPPRESSION OF NATURAL OSCILLATION”, filed Nov. 11, 2002, which claims priority to German Patent Application No. DE 101 55 179, entitled “DIGITAL REPEATER HAVING BANDPASS FILTERING, ADAPTIVE PRE-EQUALIZATION AND SUPPRESSION OF NATURAL OSCILLATION”, filed Nov. 12, 2001, which patents, applications, and publications are incorporated herein by reference in their entireties.
BACKGROUND OF THE INVENTION
The invention covers a repeater with a digital signal processing module with bandpass filtering as well as the suppression of the oscillation of the repeater as its major function.
Repeaters are frequently used to improve coverage in areas where the typical coverage of cellular networks or broadcast networks is insufficient. The general problem of repeater installation is that it requires the isolation between receiving and transmitting antennas to be higher than the gain of the on-frequency repeater to prevent it from oscillation.
In order to avoid oscillation for the repeater with the interference caused in the mobile communication or broadcast network, the repeater gain must be reduced by a gain margin with respect to the decoupling of the antennas. This safety gain margin is understood to be the difference between the gain of the repeater amplifier and the isolation of the antennas. Both measurements are determined with reference to the input and output terminals of the repeater and most frequently expressed in dB. The safety gain margin is frequently set to a 15 dB number that is determined at the time of the installation using an averaged measurement of the antenna decoupling. As this number is subject to environmental and weather conditions, the safety gain margin might need to change and follow those changes. Even with an active tracking mechanism of the antenna isolation, the operation of the repeater is limited in its enhancement and thus the repeater range and quality are the trade-off that causes the repeater installation to be less economical.
From DE 199 23 790 A1 the circuitry and the process to adaptively control the gain of an amplifier with feedback is known. Another variant of this is detailed in DE 197 52 283 A1. In the procedures described in DE 197 52 283 A1, the operation of the amplifier gain Vo is controlled in such a way that the gain margin relative to Vs, the gain of onset of oscillation, is maintained high enough to ensure a stable operation of the amplifier with feedback. The procedure does analyze the total gain which increases for a repeater operated close to the point of instability. To ensure the gain margin to be high enough for a continuous and safe operation of the amplifier, the circuitry and procedure described in DE 197 52 283 A1, the amplifier is continuously monitored and controlled.
In order to prevent the amplifier from oscillation, the difference between the regulated amplification Vo of the amplifier and the amplification for the onset of oscillation Vs shall not be reduced. In order to support same, the circuitry exhibits a memory for a pre-determined oscillation margin, which is defined by the ratio Vs/Vo.
Furthermore, the monitoring and data interpreting unit is designed in such a manner that it can determine the current safety gain margin of the amplifier from the change of the signal level at the amplifier output as a function of the change of the pre-determined amplification and compare this with the stored safety gain margin.
if the pre-determined safety gain margin is violated the pre-determined amplification Vo is lowered, if however the current gain does not violate the safety gain margin stored and is even larger, the amplification Vo of the amplifier is raised.
A mechanism for periodic changes of the amplifier gain can be implemented with an attenuator element for the periodic lowering of the pre-determined amplification. The pre-determined amplification of the amplifier will be lowered temporarily below the pre-determined safety gain margin during the monitoring and evaluation phase which will also reduce the probability of oscillation of the amplifier.
According to DE 197 52 283 A1, the procedure of the adaptive control of the amplification of a amplifier with feedback covers the following steps:
pre-setting the gain Vo of the amplifier; periodical change of the preset gain Vo by a pre-determined amount; supervising and evaluating a change of the level at the amplifier output during periodic changing of the preset gain; and raising or lowering preset gain Vo by a second pre-determined to be operating with a gain as close as possible to the safety gain margin without violating it.
In cellular radio networks repeater are commonly used for the extension of the coverage, e.g. in tunnels, large buildings or to supply coverage to uncovered areas, and wherever the installation of a base station is too complex.
The principle of the conventional repeater is the bi-directional amplification of radio signals in the Uplink and the Downlink direction. The radio signals remain on the same frequency as received. The Downlink signal, the signal coming from the base station of the radio network, is received with a highly directional donor antenna, amplified in the repeater, possibly filtered and re-transmitted to the mobile station via a coverage antenna. At the same time, the Uplink signal is received coming from the mobile station with the coverage antenna, is amplified in the repeater, possibly filtered and sent back to the base station via the donor antenna. The signal can be filtered either channel-selective or band-selective. Both repeater paths are usually coupled to the antenna using duplex filters. In its function to amplify, filter and re-transmit the radio signal the repeater typically introduces error (phase and amplitude errors, as well as additional noise and spurious signals), which can unfavorably affect the connection. In addition, a repeater of known design has limited dynamics: at the lower end limited by the noise of the input stages, at the higher end limited by the maximum power output power capabilities of the final power amplified stage.
In order to improve the transmission quality of the signals in repeaters, DE 196 49 853 defines a repeater for radio signals, which demodulates the received radio signals of a digital cellular radio network, transmits the data by the means of a data link (LAN, WAN) and re-modulates the data again to re-transmit the radio signal at the remote location. This repeater consists of the following functional units:
Receiver, channel filter, amplifier and demodulator for the Uplink path; Modulator and power amplifier for the Downlink path; as well as at least a data interface.
The data interface contains substantially the following functional units: Multiplexer, Demultiplexer, digital data processing control and peripheral interface adapter.
The advantage of this type of repeater is the spatial isolation of donor and coverage antenna or the economical data line instead of a high-quality high frequency line used to connect the two antenna locations. Further advantage is that problems of the signal distortion through noise, intermodulation and amplitude or phase distortions by the digital technique can be avoided. The distance between the two partial devices of the repeater can be increased to a relatively large distance without losing signal quality of the digital transmission of the demodulated signal. Limiting factor here is only the maximally permissible signal delay.
The repeater described in DE 196 49 854 is in a similar fashion demodulating the received radio signals, processing the data and re-modulates the digital data streams for transmission. Measurements of the field strength are used as a control signal to adjust the output power of the transmission amplifier. Each repeater path covers the following functional units:
Duplex filter, preamplifier, local oscillator, mixer, channel filter, demodulator, modulator and power amplifier.
In TDMA mobile networks (Time Division Multiple Access) the measurement of the received signal strength is carried out on a time slot basis. The demodulated digital data stream is amplified and injected into a modulator and re-transmitted with least possible errors. However, during this signal processing, no channel decoding is performed and the implementation is limited in its digital signal processing to minimize signal distortion and interference in order to substantially improve the quality of the radio network coverage. The functional units for each repeater path are a pre-amplifier, mixer, local oscillator, channel filter, demodulator, modulator and power amplifier, with the possibility of multiple paths aligned in parallel according to the number of required channels. The repeater can be remotely controlled and monitored over a radio data link established between the base station and the repeater favorably using the same signal the repeater is amplifying. This functionality is implemented by either a data modem coupled to the donor antenna or a device that is fed by the demodulated signals of the digital path inside the repeater.
From DE 196 49 855 A1 a mobile repeater is well-known. The radio signal coming from the mobile station is injected into a preamplifier after having passed through a duplex filter and mixed down into its base band or into an intermediate frequency band. The mixing frequency will be defined by a local oscillator. The base band or intermediate frequency signal is channel filtered and then demodulated providing a digital data stream. The signal is re-modulated onto a carrier frequency, raised in power by power amplifier and filtered with a duplex filter, and radiated via the coverage antenna to the mobile station. The mobile repeater further contains an intelligent control unit, which detects and analyzes signaling traffic between base stations and mobile stations, as well as the respective signal level. Thus it is possible to assign the coverage of the mobile stations to a dedicated base station of the most favorable of all possible base stations in the area and still support handover.
Beside the described channel selective repeaters, band selective repeaters are also well known. This unit filters re-transmits a whole frequency band with several channels. High selectivity values of the band filter are necessary to avoid disturbances close to the band limits. The problem of the linear repeater is now that feedback between the two antennas can lead to fatal interference or even oscillation. Therefore the antennas must be sufficiently decoupled for this type of repeater. In order to decrease the amount of feedback for the linear repeater, the two antennas have to be mounted far apart from each other which typically leads to high installation costs. In addition, the installation and maintenance costs are quite high as isolation has to be determined carefully during and periodically after the installation of the repeater with the possibility to re-adjust the repeater frequently.
Another way to implement a repeater based system for radio coverage is depicted in DE 196 48 178 A1, for which the injected radio signal is shifted to another frequency in the same radio band. In order to avoid that the terminals would not be able to successfully decode the information on the converted frequencies and to avoid the consequent erroneous reaction the modulation is changed to inverted side bands. For this the repeater contains:
two parallel input amplifiers for the input signals, a mixer at each output of each input amplifier, a bandpass filter at each output of each mixer, an output amplifier at each output of each filter, the outputs of the output amplifiers being joined to generate an output signal, at least one oscillator connected to the mixer, wherein each mixer shifts one frequency of the input signal to another frequency within the bandpass of the system, and the frequency position of the modulation is reflected on the frequency axis of the other frequency.
In EP 1087559 A1, a repeater for a wireless radio network is described in more detail that uses signal processing to reduce the unwanted coupling between the output of the repeater and the input. With the means of digital signal processing, an echo signal is produced that is similar to the feedback signal between the two antennas, which is then subtracted from the signal in the main path and thus eliminating the echo signal caused by the insufficient decoupling of the antennas, so that up to a remaining error, the echo is eliminated. The digital signal processing contains in detail:
an adaptive complex filter, a mechanism for adjustment of the filter coefficients, which exhibits a quadrature modulator for the conversion of the received signal or output signal to an equivalent baseband signal, a FFT processor (Fast Fourier Transform), which produces an estimated signal from the equivalent base band signal, and a DSP (digital signal processor). The DSP produces a complex impulse response from the estimated signal of the FFT processor, whereby the filter coefficients of the adaptive complex filter are adjusted in accordance with the complex impulse response. To limit the computing complexity and the convergence rate the impulse response exhibits a finite bit length/length, which corresponds to the number of filter coefficients.
In further variation of the repeater known from EP 1 087 559 A1, a digital filter with band-pass characteristic and a mechanism for adjustment of the filter coefficients is included. The mechanism for the adjustment of the filter coefficients, which consists of a FFT processor and the DSP processor are implemented as described above. In systems incorporating BST-OFDM modulation schemes (Band Segmented Transmission Orthogonal Frequency Division Multiplexing) and/or DVB-T System (Digital Video Broadcast-Terrestrial), in which the amplitudes of the carriers of the CP signal (Continual Pilot) and/or the TMCC signal (Transmission and Multiplexing Configuration Control) is constant, the accuracy of the estimate of the transfer function increases, if a rough estimation of the transfer function is made on the basis of the CP signal and/or the TMCC signal, which is contained in all symbols of the BST-OFDM signal, and a fine estimate by means of the SP signal (Scattered pilot), which is transmitted in a certain symbol interval. The introduced delay is problematic in the repeater implementation, so that the introduced delay is significantly smaller than the repeat interval of the OFDM signals.
The previous summary of the state of the art for repeater points out, that digital signal processing is well known within repeaters. The disadvantage of such a digital repeater is in the fact that the complexity of processing and/or speed of operation are demanding requirements to ensure the impact on the signal delay to still be in the acceptable range, in particular within implementation incorporating echo compensation. Although the digital conversion promises significant improvement of the technical parameters in comparison to conventional analog conversion, the digital signal processing for bi-directional amplifiers (repeater) applications with their broad field of applications in portable radio communication and data networks as well as in the common broadcast radio technology is not yet commonly established. This is even more surprising, as both the communications technology industry and telecommunications are extremely progressive and innovative industries, where improvements and simplifications are accepted and established quickly.
The invention addresses the task to minimize the complexity and costs of a repeater with digital signal processing without trading in performance in the areas of signal filtering and echo cancellation.
SUMMARY OF THE INVENTION
The solution to the above task is based upon a repeater platform with a digital signal processing incorporating bandpass filtering, adaptive distortion correction and suppression of the oscillation due to feedback. The repeater platform consists of the following components in the Uplink and Downlink path in the following order:
analog mixer for the down-conversion of the input signal, analog-to-digital converters, echo compensator using an internally generated reference signal, bandpass filter, adaptive equalizer, digital-to-analog converter, analog mixer for up-conversion, adaptive feedback repeater amplifier.
The procedure in the invention has the advantage to cover different mobile communication systems like GSM, UMTS, Tetra, IS 136 or IS 95 and user requirements in a surprisingly simple way. The complexity of circuitry is relatively small despite its possibilities and flexibility. Furthermore it is of advantage that on the signal processing platform the combination of the used digital processes result in a multifold reduction of interference.
In an embodiment of the invention, the echo compensator exhibits digital signal processing element with an FIR filter for suppression of the feedback between transmission and reception antenna. The FIR filter coefficients are derived from a computed correlation of sampled data of the input and output of the repeater path. The FIR filter basically represents the inverse of the external feedback path and the external echo is cancelled by applying it to a reference signal that is coupled off the output of the repeater and summing it into the main path of the repeater at the correct signal delay.
The use of adaptive FIR filter and DSP processor makes possible that for the computation of the correlation between input and output signal, the setup of the delay in the feedback path and the FIR filter—the complexity of processing can be reduced. The total time delay of the repeater path with the digital signal processing is relatively small in both the GSM-systems as well as in the UMTS-system and its value is easily found to be below 7 μs, even including the bandpass filter.
In further extension of the invention, the amplifier is adjustable and the reference signal is taken from the input of the amplifier, with the amplifier being completely bypassed or switched off.
The invention exhibits the advantage that the repeater can be operated at an even negative gain margin ensuring a stable performance without oscillation. The bypass or switch can be implemented economically.
Preferably, the adaptive filter mechanism to prevent oscillation exhibits an additional input, which represents the reference input of an unwanted interferer to be suppressed within the signal input. The DSP processor computes the cross correlation between the reference signal and the control signal at the output and as a result controls the delay in the reference path and the adaptive filter.
It is of advantage that despite the high selectivity also at the band limits the additional complexity of circuitry is small.
In a preferential arrangement of the invention, the implementation allows to switch in between the echo compensation or the suppression of interference.
This arrangement of the invention exhibits the advantage that depending upon application and requirement the user can configure and switch from one to the other.
Furthermore, digital down-conversion with a numerically controller oscillator is used and as the oscillator is used for both the down- and up-conversion a possible frequency shift is compensated with this implementation, with means for adaptive distortion correction being disposed between the means for digital down-conversion and digital up-conversion, the adaptive distortion correction means being connected to an additional input of the repeater.
This fact allows that the oscillators with lower frequency accuracy can be used and that this would be compensated reliably.
Preferably, the digital down-conversion consists of at least one module to decimate followed by a band filter cascaded with an up-converter followed by an integrating element and a band filter.
By this arrangement of modules to digitally down- and/or up-convert alias signals can be suppressed effectively, whereby the complex baseband signals I and Q are not affected by the decimation and/or interpolation and are unchanged within their effective bandwidth. The cascaded arrangement of band filter and decimation filter can be repeated several times (for example, 2×2), whereby respective band filter suppresses integral multiples of the image frequencies.
Finally it is provisioned that between an input mixer and an analog-digital converter a low-pass filter is arranged and between an output mixer and a digital-analog converter a further low-pass filter is used.
With the input low-pass filter noise can be suppressed, so that it does not fold into the used frequency band and with the output low-pass filter, higher order alias signals due to the digital signal processing are effectively suppressed.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages and details can be taken out of the following description of a preferred design approach of the invention with reference to the diagrams. In the diagrams is shown:
FIG. 1 the block diagram of an implementation example of the arrangement according to invention for a GSM-system and
FIG. 2 the block diagram of an implementation example of the arrangement according to invention for a UMTS-system,
FIG. 3 the block diagram of an implementation example to the echo compensation both in the GSM-system and in the UMTS-system,
FIG. 4 the block diagram of an implementation example for the suppression of interference in both a GSM-system and in a UMTS-system and
FIG. 5 the repeater for an implementation example after FIG. 2 .
FIGS. 1 and 2 depict a digital signal processing modules according to invention with the following functions:
signal filtering in the repeater, suppression of the output echo received at the input of the repeater, suppression of the signals produced in the repeater and suppression of the environmental interference from outside of the repeater.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given below, serve to explain the principles of the invention.
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 sequence of operations as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes of various illustrated components, will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration.
DETAILED DESCRIPTION OF THE INVENTION
The digital signal processing module consists of a receiver, a channel filter and a transmitter. The receiver module at least exhibits the cascade of a down-converting analogue mixer including a filter for the RF input signal, an analogue-digital converter, decimation stages and filters and digital down converter. The transmitter module contains as a minimum the cascade of an interpolating filter, a distortion corrector, digital up-converter, digital-analogue-converter and an analogue up-conversion mixer. Alternatively both down-conversion and up-conversion can be direct to/from base band.
In the following, the block diagram as seen in FIG. 1 and FIG. 2 as a possible implementation of the invention for the GSM-system and for the UMTS system will be explained in detail. The digital signal processing module in this example is capable of processing up to four GSM channels or two adjacent UMTS channels. Four bi-directional GSM band segments can be processed in parallel by one module in the Uplink branch UZ (see FIG. 5 ) and Downlink branch DZ (see FIG. 5 ) of the repeater. Each segment has a range from 200 kHz to 6.25 MHz, so that an overall bandwidth of 25 MHz is achievable. The respective bandwidth is programmed through a set of filter coefficients for the channel filter (see 11 in FIG. 1 and FIG. 2 ), whereby the filter coefficients are computed off-line (see 10 , 20 in FIG. 1 and FIG. 2 ). For all four segments only one analogue input circuitry (see FIG. 1 ) is intended.
The carrier frequency of the input signal of the GSM-system as described in the following on the basis of FIG. 1 is 140 MHz. For this frequency range commercial SAW-filter 1 and 17 (surface acoustic wave filters) with a group delay of 1.17 μs having a tolerance bandwidth between 17 nsec and 50 nsec and a rejection of 50 dB to 60 dB to suppress the image frequency are readily available. Preferably between SAW-filter 1 and the mixer 3 a variable gain amplifier 2 is positioned to prevent the analogue-digital converter to be overdriven. The adjustable amplifier 2 is controlled by a detector at the amplifier input with a maximum time constant of 20 μs. The mixer 3 shall not cause interference with the active input signals, so that preferably a double-balanced mixer is selected. A low-pass filter 4 in front of the analog-digital converter 5 suppresses noise, which could alias back in the used frequency band between 127.5 MHz and 152.5 MHz.
An example for the analog-to-digital conversion a converter 5 with a maximum sample rate of 80 Mbit/s and a resolution of 14 bits can be used. The SNR relationship is for a signal with 30.5 MHz and −1 dBFS at the maximum conversion rate is about 73.5 dB. For the suppression of the alias band between 47 MHz and 72 MHz the sampling rate of the analog-to-digital converter 5 is preferably selected to 77 MHz, which allows the use of a less complex low-pass filter for 4 with an edge frequency of 33 MHz.
The echo cancellation 6 is used with GSM, UMTS and IS 95 as examples; details are represented in FIG. 3 . The feedback between transmission and receiving antenna can be cancelled by a FIR filter 7 . According to the invention the transfer function of the feedback path is computed, the inverse transfer function and the FIR-filter coefficients are adjusted to minimize the remnant of the feedback signal that will be re-transmitted. A DSP processor 10 read the samples captured at the input A and at the output O out of buffer 9 , to compute the correlation between A and O and determine the required delay time (in Z) in the feedback path and the FIR filter 7 . In order to realize the FIR filter 7 , dedicated integrated filter circuits are available (e.g. two Gray Chips). In the GSM-system the sum of the 4-Segment output signals can be used to derive the control for the adaptive filter settings.
In the UMTS-system as shown in FIG. 3 , the digital complex base band signal is used to control the adaptive filter settings. The signal is thus split off before the linearization circuit Lin and/or the distortion correction circuit V (see FIG. 2 ).
Depending on the selected FIR filter structure, a wider range of delay spread for the feedback signal can be cancelled, provided that the delay of the feedback with the longest delay is smaller than the delay of the FIR filter. An adaptive filter will adjust to the individual delay pattern.
For the suppression of external interferers in receive band the digital repeater has an additional input B to the adaptive filter 7 as shown in FIG. 4 for both the GSM-system and/or UMTS-system. This input B represents the reference input of the unwanted interfering signal. The DSP processor 10 computes the cross correlation between the reference signal B and the control signal at the exit O and in accordance with their condition the delay (in Z) in the feedback path and FIR filter 7 is adjusted.
According to invention the aforementioned cancellation mechanism can be used for both the echo cancellation and the suppression of interference, as it immediately visible by comparing FIG. 3 and FIG. 4 .
The echo compensation and/or interference canceller follows a digital down-converters 8 section. It consists of four digital mixers to divide the input signal into four complex base band segments. For each segment a digital numerically computed in-phase quadrature oscillator NCO is fed into the digital mixer 8 . The output of the digital mixer is a complex base band signal. The oscillator NCO is used in both cases for the down-conversion as well as for the up-conversion. The oscillator signal is 14 bits wide and operates at a clock frequency of 77 MHz. The tuning step size the oscillator output frequency is thus limited to 4,699.707 cycles per second and the center frequency of the channel filter can be adjusted with an accuracy of ±2.350 cycles per second around the desired signal. The oscillator NCO can be tuned within an interval of approximately 5 MHz to 30 MHz. In case of frequency hopping the hopping frequencies and the timing procedure is calculated by the controller 20 . In order to allow smaller oscillator tuning steps the resolution of the oscillator can be increased resulting in more resources required. As the oscillator NCO is used for down- as well as for up-conversion, a possible frequency error will be compensated.
The output of the device 8 provides an I component and Q component in the complex base-band with a sample rate of 77 MHz. In the implementation example, the bandwidth of segment is max. 6.25 MHz. In order to reduce the data rate and avoid aliasing, a decimation filter and stage is following, which consists of a cascade of a decimation filter H and a decimation stage D exhibiting a decimation by a factor 2, a second decimation filter H and again means D to decimate by a factor of 2. In detail the decimation reduces the sample rate to 19.25 MHz (¼ of sample rate of 77 MHz), whereby the base-band signals I and Q are not affected by the decimation and further exhibit a bandwidth of 3.125 MHz. For the dimensioning of the filters H, the mirror frequencies proximate 19.25 MHz, 57.75 MHz for the second decimation filter H and proximate 38.5 MHz, 77 MHz for the first decimation filter H must be treated with care, since signals with integer multiples of 19.25 MHz would otherwise appear as alias signals at the decimation output. With increasing base band bandwidth the requirements on the decimation filter become more stringent.
With the implementation example with four GSM-segments as band-pass filter 11 a 128-wide FIR filters with linear phase is used at a sample rate of 19.25 MHz. The filter coefficients are stored in memory or computed off-line (in 10, 20). By setting the filter coefficients the bandwidth is determined. The implementation example results in a group delay of the channel filter 11 of approximately 2.9 μs.
The following transmitter contains the interpolator, which consists of a cascade of element I to interpolate by a factor of 2 and a band filter H, repeated again, representing a total interpolation of a factor 4, whereby the sample rate at the exit of the interpolating stage is again 77 Mbit/s. The digital up-converter 12 corresponds to a digital I/Q modulator to an intermediate frequency between 5 MHz and 30 MHz. The digital-to-analog converter 14 convert the intermediate frequency signal into an analog intermediate frequency band with a 77 MHz sampling frequency and a resolution of 14 bits. For each segment an analogue-digital converter 14 is intended. Finally the transmitter exhibits a mixer 16 to the up-conversion to the final radio frequency band.
The digital-to-analog converter 14 is followed by a low-pass interpolation filter 15 to suppress image frequencies of digital signal. The 1 dB edge frequency in the implementation example is approx. 33 MHz. The oscillator (the source of clock CG with 77 MHz and/or 122.5 MHz) corresponds to the same oscillator in the receiving path, which allows the phase noise impact of this oscillator to the repeated signal to be compensated and minimized. A SAW band filter 17 at the output of the mixer 16 allows rejecting spurious frequencies. The output signal O of the transmitter part within the described implementation example is centered on 140 MHz and exhibits a bandwidth of 25 MHz. For four GSM segments and/or for the four mixers the same oscillator is used.
The total group delay of the digital signal processing repeater path including receiver module, channel filter module and transmitter amounts to 6.46 μs for a 200 kHz channel in the GSM-system and/or to 6.42 μs for a 6.25 MHz segment. Essential contributors to the total group delay are the SAW-bandpass filter with 2*1.17 μs in the receiver and transmitter the channel filter 11 with 2.89 μs (and/or 2.85 μs for the band segment).
A controller 20 is communicating to the DSP processor 10 in order to configure and control the repeater and its modules. The list of functions of the DSP processor 10 are: determination and configuration of the necessary delay and filter coefficients for the adaptive FIR filter 7 , configuration of the channel filters 11 as well as monitoring of the modules. The local oscillator for the RF mixers 3 and 16 as well as the clock oscillator for the digital signal processing section is generated in the central reference clock oscillator module CG. Further the repeater exhibits a current supply 30 with 5 V DC and 3.3 V DC for digital and analog circuits.
A block diagram of an execution form of an arrangement according to invention for the UMTS-system will be detailed in the following using FIG. 2 . As already detailed for the GSM system in FIG. 1 , the digital signal processing module is capable to process a maximum of two adjacent UMTS RF channels as one block. Since each UMTS channel has a bandwidth of 5 MHz, the resulting bandwidth is 10 MHz. The one block consisting of up to two UMTS channels is treating the individual UMTS channel not separately but as one signal with channel filtering and a distortion correction processing affecting the whole signal as a block.
The receiver module expects two adjacent channels at a center frequency of 140 MHz. Similar to the GSM-system (see FIG. 1 ) commercial SAW-filter 1 now with a bandwidth of 10 MHz and one group delay time of 1.92 μs are planned. The mixer 3 in the receiver module is operated with a oscillator frequency of 115.5 MHz resulting in an intermediate frequency output of 24.5 MHz. The analog-to-digital converter 5 is similar as in the GSM-system and likewise is operated at a clock frequency of 77 MHz. The echo compensation is identical to the GSM system as well (see FIG. 1 and FIG. 3 ).
The digital numerically controlled oscillator NCO for the two digital mixers 8 used for the conversion of the signal to the complex base-band is operated at 77 MHz with 14 bits width. The NCO is tuned to 24.5 MHz and its tuning step size is 7,049.56 cycles per second.
At the output of the mixer 8 decimation stage and filter (with H, D) are used to reduce the sample rate similar to the GSM-system. The I- and Q-signal components in the base-band are not modified by the decimation and continue to exhibit a range of ±5 MHz.
Also the bandpass filter 11 corresponds to the filter for the GSM-system as described above, whereas here the filter is optimized for two UMTS channels.
The following transmitter module contains an interpolating element, which accomplishes the interpolation in two steps: the first interpolation by a factor 3 (changing the sampling rate from 19.25 MHz to 57.75 MHz) followed by the distortion corrector V and the second interpolation by a factor 2 after the distortion corrector V. Again arranged interpolation filter H are intended to suppress the image frequencies. Accordingly, the bandwidth of the I and Q components is preferably increased from 10 MHz to 30 MHz. The second interpolating element changes the sampling frequency to 115.5 MHz and an interpolation filter H follows to suppress the unwanted image frequencies.
A digital quadrature upconversion stage 12 combines the I and Q components and convert them to an intermediate frequency of 24.5 MHz. The digital numerically controlled oscillator NCO is operated at the sample clock frequency of 115.5 MHz which is 1.5 times the frequency of the NCO sample clock used in the downconversion.
Finally a digital-to-analog converter 14 followed by a low-pass filter 15 convert the signal in an analog signal at 24.5 MHz intermediate frequency. An upconversion mixer 16 and SAW bandpass filter 17 convert the signal further to the intermediate frequency of 140 MHz used in the repeater system. The total group delay of the digital signal processing module consisting of receiver module, channel filter module and transmitter increased in comparison to the GSM system slightly and amounts to 6.96 μs for one UMTS channel and/or 6.92 μs for two UMTS channel. Essential contributions to the group delay come from the SAW-bandpass filter in the receiver and transmitter with 1.92 μs and 1.11 μs and of the channel filter with 2.59 μs (or 2.55 μs for two UMTS channel).
The DSP processor 10 , the system clock generator CG, and the current supply 30 have the same function as detailed in the description of the GSM system. Details of the whole repeater and its internal procedures are depicted in FIG. 5 and will be described briefly in the following with reference to the respective components.
A duplex filter is disposed at each input or output of the uplink branch UZ or downlink branch DZ of the repeater and is connected to an amplifier LA and a combining network K. A splitter network is disposed between the amplifier LA of the uplink branch UZ or downlink branch DZ and the analog mixer 3 for down conversion of the input signal. The adaptive feedback coupled amplifier PA (feedback coupling via 3 ′ and 5 ′) is connected to the combining network K of the downlink branch DZ or uplink branch UZ. This repeater amplifier 5 input is connected to the output of the analog mixer 16 .
Digital signal processing according to invention can also be used in the TETRA system, IS 136 system, or IS 95/2000 system.
The costs of digital signal processing are determined by the costs of the analog-to-digital converters, digital-to-analog converters, FPGAs, DSPs, ASICs, and the required peripheral circuitry to implement the various stages required in the digital signal processing line up. For the employment of repeater systems with different required number of channels a modular architecture of the signal processing platform is beneficial.
Partitioning the various sub modules of the Downlink or Uplink paths can be realized in various ways. One approach will be described in detail. The receiver block as a combination of the analog downconversion to an intermediate frequency including bandpass filtering and analog-to-digital conversion is one possible block. A digital processing main block consisting of digital downconverter, decimation stages, channel filter, interpolation stages, linearization stages, digital upconverter, clock generation, and power supply is forming the major digital signal processing platform. The transmitter exhibits the digital-to-analog conversion, the RF upconversion including bandpass filtering. For all different systems (GSM, UMTS, and IS 95/2000) the mainboard is not necessarily different, while different receiver modules and transmitter modules are required for the different frequency bands.
In contrast to well-known repeaters with a digital signal processing module the digital repeater in the described invention would operate without change in the system concept with different wireless mobile systems. It is particularly favorable that only a re-configuration in the modules is necessary by the user, who can switch between the modes of operation, so that the specific requirements in different systems are away ensured.
In the comparison to the well-known state of the art the arrangement according to the invention demands no parallel processing or hardware line-ups and finally permits various application types at surprisingly small expenditure, and in addition the possibility to upgrade existing systems as well as the flexible and economical administration and configuration.
All represented and described variations of implementation, as well as all in the description and the design revealed new single characteristics and their combination among themselves, are essential for the invention. For example a digital filter can be used to replace a SAW band filter.
While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details representative apparatus and method, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of applicant's general inventive concept. | A signal repeating system includes at least one input antenna that receives input signals, at least one output antenna that radiates output signals, and a signal path between the input and output antennas. The signal path includes circuitry for conditioning the input signals with down conversion circuitry that converts input signals to lower frequency signals and analog-to-digital conversion circuitry that converts the input signals to digital signals. A suppression circuit suppresses feedback and interference in the repeated output signals with a digital signal processor configured for receiving samples of the input signals, samples of the output signals, and samples of an interference reference signal and an adaptive filter under the control of the digital signal processor for generating echo cancellation signals and interference cancellation signals. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to a composition comprising a granulate and a matrix obtainable by a self selective reaction of at least two precursors forming a three dimensional network. A kit and a method for preparing said composition are also provided.
BACKGROUND
[0002] Medical devices such as implants in general and dental implants in particular are widely used nowadays. They have become an appreciated possibility where hard tissue structures need to be fixed or replaced, e.g. in the case of bone fractures or tooth loss. However, the success of such implants strongly depends on adequate support at the implant site. If the bone mass at said site is insufficient or poor in quality, bone repair and/or bone augmentation becomes a necessity. There are different treatments applied to regain sufficient bone mass, including the use of bone graft materials of different origin, shape and size.
[0003] While there are ways to systemically treat the mass and/or strength of the bone, e.g. in osteoporosis, it is still difficult to achieve bone formation in a reliable and controllable manner. However, local bone formation would greatly benefit the adequate treatment of incidents where enhancing the bone volume is only required locally, e.g. when placing dental implants.
[0004] Methods currently used to repair bone defects include graft materials from different sources. The material is either synthetic or of natural origin. One natural graft material which is employed is autogenous bone. In contrast to bone/bone like material from natural sources (human, animals, plants, algae etc.), autogenous bone material does not trigger a strong immune response and is thus not rejected by the host. However, autogenous bone material requires a second surgery for harvesting the bone increasing the risk of unwanted infection and/or inflammation at this site and significantly increases treatment costs. Further, the removal of bone material leads, at least temporarily, to a weakened structure at this site and causes a painful healing process.
[0005] During the last years it became more and more clear that the use of various bioactive factors improves bone repair and/or bone augmentation. It has also been shown that the method of application of such factors greatly influences their regenerative effect. Despite continuous efforts to develop methods for the controllable presentation and release of said factors, this is still one of the common problems in this field.
[0006] In the state of the art, different biomaterials for tissue augmentation or release of bioactive factors have been described.
[0007] WO 00/44808 discloses a polymeric biomaterial formed by nucleophilic addition reactions to conjugated unsaturated groups. The obtained biomaterial, which is in the form of a hydrogel, may be used for example as glues or sealants and as scaffolds for tissue engineering and wound healing applications. Also said hydrogels degrade fast under physiological conditions.
[0008] U.S. Pat. No. 5,626,861 discloses a method for the fabrication of a macroporous matrix that may be used as implant material. The composites are formed from a mixture of biodegradable and biocompatible polymer which is dissolved in an organic solvent such as methylene chloride or chloroform and then mixed with hydroxyapatite. The latter is a particulate calcium phosphate ceramic. The material has irregular pores in the size range between 100 and 250 microns. Bioactive factors may be non-covalently incorporated in the composite.
[0009] U.S. Pat. No. 5,204,382 describes injectable implant compositions comprising a biocompatible ceramic matrix mixed with an organic polymer or collagen suspended in a fluid carrier. The ceramic particles are in the size range of 50 μm to 250 μm.
[0010] U.S. Pat. No. 6,417,247 discloses polymer and a ceramic matrix. The compositions are normally liquid and harden upon a certain stimulus, e.g. elevated temperatures.
[0011] WO 2004/103421 describes a hydroxylapatite/silicon dioxide material having a defined morphology. A highly porous bone substitute material based on the hydroxylapatite/silicon dioxide material is also described.
[0012] WO 03/040235 discloses a synthetic matrix for controlled cell ingrowth and tissue regeneration. The matrix comprises a three-dimensional polymeric network formed by multi-functional precursors.
[0013] WO 2004/054633 describes a macroporous synthetic ceramic which can be used to produce granulated bone substitute material.
[0014] EP 0 324 425 discloses a method for producing a medical bone prosthesis using at least one of α-tricalcium phosphate and tetracalcium phosphate.
[0015] US 2004/0019132 describes methods and compositions for manufacturing a bone graft substitute. A powder compaction process is used to generate a shaped product comprising granulated bone material, such as demineralized bone matrix.
[0016] WO 03/092760 discloses a structured composite as a carrier for the tissue engineering and implant material of bones, consisting of a mass of porous calcium phosphate granulates.
[0017] WO 2006/072622 describes supplemented matrices comprising a PTH releasably incorporated therein, optionally containing a granular material.
[0018] As used herein, the words “polymerization” and “cross-linking” are used to indicate the linking of different precursors to each other to result in a substantial increase in molecular weight. “Cross-linking” further indicates branching, typically to obtain a three dimensional polymer network.
[0019] By “self selective” is meant that a first precursor A of the reaction reacts much faster with a second precursor B than with other compounds present in the mixture at the site of the reaction, and the second precursor B reacts much faster with the first precursor A than with other compounds present in the mixture at the site of the reaction. The mixture may contain other biological materials, for example, drugs, peptides, proteins, DNA, RNA, cells, cell aggregates and tissues.
[0020] By “conjugated unsaturated bond” the alternation of carbon-carbon, carbon-heteroatom or heteroatom-heteroatom multiple bonds with single bonds is meant. Such bonds can undergo addition reactions.
[0021] By “conjugated unsaturated group” a molecule or a region of a molecule, containing an alternation of carbon-carbon, carbon-heteroatom or heteroatom-heteroatom multiple bonds with single bonds, which has a multiple bond which can undergo addition reactions is meant. Examples of conjugated unsaturated groups include, but are not limited to acrylates, acrylamides, quinines, and vinylpyridiniums, for example 2- or 4-vinylpyridinium.
SUMMARY OF THE INVENTION
[0022] The problem of the present invention is to provide a bone repair and/or bone augmentation material which has an excellent biocompatibility and mechanical stability allowing in situ repair of the bone defect and/or bone augmentation while minimizing the risk of unwanted inflammation, eliminating the need for second surgery for harvesting autogenous bone material and not bearing the risk of infection. In addition, the treatment costs are significantly reduced.
[0023] The composition according to one embodiment of the present invention comprises a granulate and a degradable polymeric matrix. Several cross-linked substances are known in the art, which are able to provide a porous three-dimensional biodegradable matrix suitable for tissue regeneration and obtainable by a self selective reaction. An example for a polymeric material is PEG.
[0024] In one preferred embodiment, such polymeric matrix is obtained by a self selective reaction of two or more precursors, as defined below, in the presence of water. The combination of said granulate and said matrix yields a composition having excellent bone repair and/or bone augmentation properties. The combination of said matrix with said granulate synergistically improves the bone repair and/or bone augmentation. While the matrix provides a three-dimensional scaffold, the granulate ensures a good mechanical stability. Since precursors forming the matrix and granulate are preferably mixed just prior to use, an optimal distribution of the granulate throughout the entire composition can be achieved. The precursors, which are the monomers forming the matrix, are soluble in water. It is important to note that precursors and not polymers are mixed with the granulate allowing the formation of the matrix in situ. Consequently, the aqueous solution comprising the precursors and the granulate is not viscous and can be rapidly mixed without difficulties. The rapid generation of the matrix preserves the optimal distribution of the granulate and avoids imbalances due to possible sedimentation of the granulate.
[0025] Furthermore, the combination of a hydrogel matrix and granulate allows modelling of the granular putty to the desired shape, stabilizes the shape and prevents granulate migration.
[0026] If appropriate, a viscosity modifier, such as CMC (carboxymethylcellulose), PGA (propylene glycol alginate) or Xanthan, can be added to ensure optimal physical properties for administration in situ, e.g. in case a relatively large amount of liquid should be added to the granules. Thus, uniform and optimal bone repair and/or bone augmentation properties are ensured throughout the entire three-dimensional structure formed by the composition.
[0027] In previously known treatments, the bone filler material is applied upon mixing with non polymerizing liquids, e.g. NaCl solutions or blood. As a result, the administered bone grafting mixture may not provide for an accurate stability required for successful new hard tissue formation. The bone graft material is usually exposed to mechanical stress due to the overlying layer of soft tissue or other impacts, which can lead to the deformation, migration or even collapse of the augmentate.
[0028] The composition of the present invention will overcome this problem by the combination of an appropriate filler material, e.g. calcium phosphate granulate, and a polymeric matrix, e.g. PEG, and thereby provide for controlled and safe bone repair and/or bone augmentation.
[0029] Apart from the simple handling, the single components of the composition, the precursors forming the matrix and the granulate, have an excellent stability and thus a long shelf life. Advantageously, the components are stored in a dry form, e.g. as a powder, and the precursors are dissolved immediately prior to application. Alternatively, the components may be stored in solvents that protect their functionalities.
[0030] Further, in various embodiments the composition is biodegradable thereby leaving space for natural bone to grow into. Again, this avoids surgery in order to remove remaining parts of the bone repair and/or bone augmentation material subsequently to the completed healing of the bone defect. The degradation products are easily excreted and non-toxic.
[0031] The granulate serves on one hand as a filler expanding the volume of the composition and, on the other hand, it provides the necessary mechanical strength of the composition. Furthermore, it preferably offers a scaffold surface for bone deposition. There is a wide variety of materials which can be employed as granulate, e.g. bone materials or synthetic materials. Examples of granulate materials are autograft bone, hydroxyapatite, tricalcium phosphate and mixtures thereof.
[0032] Further examples of granulate materials include autogenous bone materials such as chin, retromolar and nasal spine (all harvested intraorally), crista, iliaca and calotte (all harvested extraorally), bone/bone like materials from natural sources such as freeze dried bone allograft (FDBA), demineralized freeze dried bone allograft (DFDBA; Grafton®), bovine material (BioOss®, Osteograph®, Navigraft®, Osteograft®), coralline material (Pro Osteon®, Interpore 500®), algae material (Frios Algipore®), and collagens. Synthetic materials are hydroxyapatite (Ostim®), tricalciumphosphate (Cerasorb®, BioResorb®, Ceros® etc.), mixtures of hydroxyapatite and tricalciumphosphate (Straumann BoneCeramic®), bioactive glass (PerioGlas®, Biogran®), calcium sulfate and carbonated apatite.
[0033] The synthetic materials provide the advantage that they are of non-animal origin, thus eliminating the possible risk of infection with human or animal pathogens, depending on the source of the natural materials, which is always present when not autogenous bone material but bone/bone like materials from natural sources are used. In addition, synthetic granulates eliminate the need for a second surgery, in contrast to the case when autogenous bone material is employed. Said second surgery can be a prominent source of complications and additional costs. Apart from the fact that sound bone structures are at least temporarily weakened, infections or inflammation may occur, further complicating the healing process of the surgery site which itself is already painful.
[0034] Another advantage of synthetic materials is that its manufacturing allows for control of parameters such as chemical composition, crystallinity, and porosity.
[0035] Below, precursors A and B forming the matrix are described in more detail.
[0036] The first precursor A comprises a core which carries n chains with a conjugated unsaturated group or a conjugated unsaturated bond attached to any of the last 20 atoms of the chain. In a preferred embodiment said conjugated unsaturated group or conjugated unsaturated bond is terminal. The core of the first precursor A can be a single atom such as a carbon or a nitrogen atom or a small molecule such as an ethylene oxide unit, an amino acid or a peptide, a sugar, a multifunctional alcohol, such as pentaerythritol, D-sorbitol, glycerol or oligoglycerol, such as hexaglycerol. The chains are linear polymers or linear or branched alkyl chains optionally comprising heteroatoms, amide groups or ester groups. Beside the chains, the core of precursor A may be additionally substituted with linear or branched alkyl residues or polymers which have no conjugated unsaturated groups or bonds. In a preferred embodiment the first precursor A has 2 to 10 chains, preferably 2-8, more preferably 3-8, most preferably 4-8 chains. The conjugated unsaturated bonds are preferably acrylates, acrylamides, quinines, 2- or 4-vinylpyridiniums, vinylsulfone, maleimide or itaconate esters of formula Ia or Ib
[0000]
[0000] wherein R 1 and R 2 are independently hydrogen, methyl, ethyl, propyl or butyl, and R 3 is a linear or branched C 1 to C 10 hydrocarbon chain, preferably methyl, ethyl, propyl or butyl.
[0037] The second precursor B comprises a core carrying m chains each having a thiol or an amine group attached to any of the last 20 atoms at the end of the chain. For example a cysteine residue may be incorporated into the chain. Preferably the thiol group is terminal. The core of the second precursor B can be a single atom such as a carbon or a nitrogen atom or a small molecule such as an ethylene oxide unit, an amino acid or a peptide, a sugar, a multifunctional alcohol, such as pentaerythritol, D-sorbitol, glycerol or oligoglycerol, such as hexaglycerol. The chains are linear polymers or linear or branched alkyl chains optionally comprising heteroatoms, esters groups or amide groups. In a preferred embodiment the second precursor B has 2 to 10 chains, preferably 2-8, more preferably 2-6, most preferably 2 to 4 chains.
[0038] In a preferred embodiment, the core of precursor B comprises a peptide which comprises one or more enzymatic degradation sites. Examples for enzymatic degradation sites are substrate sequences for plasmin, matrix metallo-proteinases and the like.
[0039] In a preferred embodiment, precursor A and/or B comprises a peptide which comprises one or more enzymatic degradation sites. Precursor A and/or B can also be a peptide comprising 2 cysteine residues and one or more enzymatic degradation sites. Such precursors are described in WO 03/040235 which is incorporated herein by reference. Examples for enzymatic degradation sites are substrate sequences for plasmin, matrix metallo-proteinases and the like.
[0040] In a preferred embodiment a precursor which comprises a peptide or is a peptide comprising 2 cysteine residues and one or more enzymatic degradation sites as described for precursor B can be used as a third precursor.
[0041] The first precursor A compound has n chains, whereby n is greater than or equal to 2, and the second precursor B compound has m chains, whereby m is greater than or equal to 2. The first precursor A and/or the second precursor B may comprise further chains which are not functionalized. The sum of the functionalized chains of the first and the second precursor, that means m+n, is greater than or equal to 5. Preferably the sum of m+n is equal to or greater than 6 to obtain a well formed three-dimensional network.
[0042] The precursors forming the matrix are preferably dissolved or suspended in aqueous solutions. The precursors do not necessarily have to be entirely water-soluble.
[0043] The granulate can be wetted with the precursor solutions or suspended in a larger amount of precursor solutions.
[0044] Since no organic solvents are necessary, preferably only aqueous solutions and/or suspensions are present. These are easy to handle and do not require any laborious precautions as might be the case if organic solvents are present. Further, organic solvents may be an additional risk for the health of the staff and the patients exposed to these solvents. The present invention eliminates this risk.
[0045] The use of at least two precursors which form a three dimensional network by a self selective reaction can advantageously be applied in situ. This means, the composition can be brought to the site of the bone defect in the form of a liquid or paste, allowing a precise control of the amount of composition applied. The still liquid composition optimally adopts the shape of the bone defect, ensuring optimal fit and hold. Furthermore, it allows modeling of the composition to the desired shape. No further fixation is needed. The hardening of the composition can be completed within minutes, starting at the time of mixing. It preferably does not require any complicated triggering stimulus and the self selectivity of the reaction is such that surrounding tissue is not harmed.
[0046] In a preferred embodiment the granulate comprises calciumphosphate, which is highly biocompatible in terms that it is inert, i.e., does not elicit inflammatory processes or further unwanted biological reactions.
[0047] In a further preferred embodiment the granulate comprises hydroxyapatite (HA) and/or tricalciumphosphate (TCP).
[0048] In a preferred embodiment the composition comprises a granulate wherein the weight ratio of hydroxyapatite/tricalciumphosphate in the granulate is between 0.1 to 5.0, preferably between 1.0 to 4.0, and most preferably between 1.0 to 2.0.
[0049] In another preferred embodiment the content of hydroxyapatite (HA) in the granulate is at least 1% by weight, preferably equal to or more than 15% by weight, and most preferably equal to or more than 50% by weight.
[0050] The mechanical strength of the composition is greatly influenced by the amount of granulate present in the composition. Good results are achieved with compositions comprising 10% to 80% by weight granulate. Preferred is the range of 20% to 70% and most preferred is the range of 30% to 60%.
[0051] In a further preferred embodiment the conjugated unsaturated group or the conjugated unsaturated bond of first precursor A is an acrylate, a quinine, a 2- or 4-vinylpyridinium, vinylsulfone, maleimide or an itaconate ester of formula Ia or Ib.
[0000]
[0052] Most preferred are acrylates.
[0053] In a particularly preferred embodiment precursor A is chosen from the group consisting of
[0000]
[0054] In another preferred embodiment precursor B comprises a thiol moiety or is selected from the group consisting of
[0000]
[0055] Most preferred precursor A is a PEG-acrylate carrying 4 chains and having a molecular weight of approximately 15,000 Da. Most preferred precursors B are selected from the group consisting of a linear PEG-dithiol having a molecular weight of approximately 3500 Da and PEG-thiol carrying 4 chains and having a molecular weight of about 2400 Da.
[0056] Precursor A and/or B can significantly vary in their molecular weight, preferably in the range of 500 Da to 100,000 Da, more preferably in the range of 1000 to 50,000 and most preferably in the range of 2000 to 30,000.
[0057] In a preferred embodiment the chains of precursor A and/or B are a polymer selected from the group consisting of polyvinyl alcohol), poly(alkylene oxides), polyethylene glycol), poly(oxyethylated polyols), poly(oxyethylated sorbitol, poly(oxyethylated glucose), poly(oxazoline), poly(acryloyl-morpholine), poly(vinylpyrrolidone), and mixtures thereof. In a particularly preferred embodiment the chains of precursor A and/or B are poly(ethylene glycol). The poly(ethylene glycol) can be either linear or branched.
[0058] In another preferred embodiment precursor A is used with a precursor B which is a peptide comprising 2 cysteine residues and one or more enzymatic degradation sites. The cysteine residues are preferably located at the terminus of the peptide.
[0059] In a preferred embodiment the composition comprises at least one bioactive factor. The bioactive factor can be added when mixing the other components of the composition. If the bioactive factor does not comprise a reactive group, e.g. a thiol or an amine group, said bioactive factor will not be covalently bound to the matrix, but simply be entrapped in the composition. The bioactive factor is then released by diffusion. However, the factor may also be covalently bound to the matrix, e.g., this can be achieved by a thiol moiety present in the bioactive factor which reacts with the conjugated unsaturated group or bond present in precursor A upon mixing. A thiol moiety is preferably present, e.g. in the amino acid cysteine. This amino acid can easily be introduced in peptides, oligo-peptides or proteins. It is also possible to adsorb the bioactive factor on the granules prior to the mixing of the granules with solutions comprising the first precursor A and the second precursor B.
[0060] In a preferred embodiment the bioactive factor is selected from the group consisting of parathyroid hormones (PTH), peptides based on PTH, peptide fragments of PTH, peptides comprising an RGD tripeptide, transforming growth factor beta family (TGFβ), bone morphogenetic protein family (BMP), platelet derived growth factor family (PDGF), vascular endothelial growth factor family (VEGF), insulin like growth factor family (IGF), fibroblast growth factor family (FGF), enamel matrix derivative proteins and peptides (EMD) as described in EP 01165102 B1, prostaglandin E 2 (PGE 2 ) and EP2 agonists, and dentonin. Dentonin is a peptide fragment of matrix extracellular phosphoglycoprotein (MEPE) found in bone and dental tissues. It is further described in WO 02/14360. Also, extracellular matrix proteins, such as fibronectin, collagen, and laminin, may be used as bioactive factors. These peptides and proteins may or may not comprise additional cysteine. Such cysteine facilitates the covalent attachment of the peptides and proteins to the matrix.
[0061] In another preferred embodiment the bioactive factor is selected from the group consisting of parathyroid hormones (PTH), peptides based on PTH and peptide fragments of PTH. Parathyroid hormones have been shown to exert multiple anabolic effects on bone tissue. Particularly preferred is a peptide comprising the first 34 amino acids of PTH. This peptide may or may not contain an additional cysteine, which facilitates the covalent attachment of the peptide to the matrix. Such peptides can be produced by enzymatic cleavage of PTH or by peptide synthesis. In a further preferred embodiment the bioactive factor is selected from the group consisting of amelogenin, amelin, tuftelin, ameloblastin, enamelin and dentin sialoprotein.
[0062] The effectiveness of the matrix can be enhanced by introduction of cell attachment sites. For example, the RGD sequence motif plays an important role in specific cell adhesion. A possible cell attachment peptide is H-Gly-Cys-Gly-Arg-Gly-Asp-Ser-Pro-Gly-NH 2 , which can be covalently attached to the matrix through its cysteine.
[0063] The bioactive factors may be prepared from natural sources, by synthetic or recombinant means or a mixture thereof.
[0064] The present invention also relates to kits used to prepare a composition according to the present invention. The kit comprises (i) a granulate, (ii) a precursor A and (iii) a precursor B which are each individually stored. The kit may also comprise more than one granulate and more than two precursors.
[0065] In a preferred embodiment the kit also comprises at least one bioactive factor as a further component (iv) which is individually stored as well. If desired, the kit may comprise two or more bioactive factors stored as a premix or, preferably, individually stored. In the latter case, the factors can be mixed when the kit is used according to specific needs of the patient.
[0066] It is also possible that the kit comprises certain components in premixed form. For instance, the granulate and precursor A can be stored as premix, the granulate and precursor B can be stored as premix and also precursor B and the bioactive factor can be stored as premix. The precursors can be stored in dry form or in a suitable solvent (e.g. 0.04% acetic acid). A suitable buffer solution can be added immediately prior to application. The precursors are preferably stored in a dry form. The bioactive factor can be (pre-)adsorbed to the granulate. Further, the bioactive factor can be stored in a dry (lyophilized) form or in an aqueous solution which is suitably buffered. The former provides excellent stability and thus a long shelf life, the latter provides a very user-friendly handling.
[0067] A method for preparing a composition according to the present invention is also provided. For this purpose, the granulate, the precursor A and the precursor B are mixed in the presence of water. Preferably, the water is buffered near or at the physiological pH. A suitable buffering range for the matrix is pH 7.4 to 9.0. The polymerization preferably starts upon mixing of the different components and a hydrogel is formed within a quite short period of time (10 seconds up to 10 minutes). The precursors do not necessarily have to be completely water soluble.
[0068] The mixing of the different components can be achieved in several ways. If the precursors A and B are stored as aqueous solutions they can be mixed with the granulate by means of a suitable mixing device. Preferably they are filter sterilized just prior to their use. Most preferably, the components are sterilized at the time of production and packed in such a way that sterility is preserved. If the components are stored in powder form, they can each be dissolved in an appropriate buffered aqueous solution.
[0069] If the kit comprises a bioactive factor, the factor may be premixed or pre-reacted with any of the precursors or added separately in dry or lyophilized form or dissolved state. For instance, if the bioactive factor comprises a thiol, it can be pre-reacted with precursor A. The bioactive factor can also be preadsorbed to the granulate prior to mixing with the precursors A and B.
[0070] The present invention also relates to the use of the composition as material for bone repair and/or bone augmentation.
[0071] In a preferred embodiment the composition according to the present invention is used as bone repair and/or bone augmentation material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0072] FIG. 1 shows a mandibular defect model with granular putty after gelation, applied by surgeon 1;
[0073] FIG. 2 shows the swelling of the hydrogel samples (9.8 wt % PEG with/without granules) against time in PBS (pH 7.4) at 37° C.; average values of 6 samples (±SD) are given;
[0074] FIG. 3 shows the area of bone regeneration for the rabbit cranial cylinder model applying granules with PEG; values are displayed as box-plots ranging from the 25 th to the 75 th quantiles, including the median and whiskers extending 1.5 times the interquartile range; and
[0075] FIG. 4 shows the percentages of mineralized bone found for the rabbit cranial cylinder model applying granules with PEG; values are displayed as box-plots ranging from the 25 th to the 75 th quantiles, including the median and whiskers extending 1.5 times the interquartile range.
DETAILED DESCRIPTION
Example 1
[0076] 164 mg (0.084 mmol thiol) of HS-PEG-SH 3.4 k (Nektar, Huntsville, Ala., USA) were dissolved in 1.71 ml of 0.05% acetic acid and 326 mg (0.083 mmol acrylate) of 4-arm PEG-acrylate 15 k (Nektar, Huntsville, Ala., USA) were dissolved in 1.55 ml of 0.05% acetic acid containing 100 ppm of methylene blue. Mixing aliquots of both PEG solutions with a 0.4 M triethanolamine/HCl buffer (pH 8.85) in a volume ratio of 1.5:1.5:1 yielded a gel in 3.5 minutes at 25° C.
[0077] Aliquots of the three solutions (V PEG-thiol :V PEG-acrylate :V buffer =1.5:1.5:1) were pipetted to HA/TCP (60%/40%) granules (Straumann Bone Ceramic, Institut Straumann AG, Basel, Switzerland) and mixed. Three surgeons independently evaluated the application properties of compositions with various granules/liquid ratios:
[0000]
Granules
(g)
Liquid (ml)
Surgeon 1
Surgeon 2
Surgeon 3
0.5
0.6
good consistency
slightly too little liquid
good application
properties
0.5
0.7
best consistency, all
good application
good application
liquid is absorbed
properties
properties
0.5
0.9
good consistency,
—
—
some liquid not
absorbed
[0078] The tests showed that the granules readily absorbed the PEG solution and the resulting granular putty was easy to apply in a mandibular defect model and yielded a stable augmentate after gelation of the PEGs.
[0079] FIG. 1 shows a mandibular defect model with granular putty after gelation, applied by surgeon 1.
Example 2
Formulation 1
[0080] 150 mg (0.47 mmol acrylate) of 8-arm PEG-acrylate 2 k were dissolved in 0.60 ml of 0.02 M triethanolamine/HCl buffer (pH 7.6) and 311 mg (0.49 mmol thiol) of 4-arm PEG-thiol 2 k were dissolved in 0.44 ml of water.
[0081] Mixing equal aliquots of both solutions yielded a gel in ca. 35 seconds at 37° C.
Formulation 2
[0082] 170 mg (0.45 mmol acrylate) of 6-arm PEG-acrylate 2 k were dissolved in 0.58 ml of 0.05 M triethanolamine/HCl buffer (pH 9.8) and 190 mg (0.47 mmol thiol) of 6-arm PEG-thiol 2 k were dissolved in 0.56 ml of water.
[0083] Mixing equal aliquots of both solutions yielded a gel in ca. 75 seconds at 37° C.
Formulation 3
[0084] 69 mg (0.018 mmol acrylate) of 4-arm PEG-acrylate 15 k were dissolved in 0.131 ml of 0.04% aqueous acetic acid containing 100 ppm methylene blue and 11 mg (0.018 mmol thiol) of 4-arm PEG-thiol 2 k were dissolved in 0.189 ml of 0.04% aqueous acetic acid.
[0085] Mixing aliquots of both PEG solutions with a 0.05 M triethanolamine/HCl buffer (pH 8.7) in a volume ratio of 1:1:3 yielded a gel in ca. 2.5 minutes at 25° C.
[0086] Mixing any of the above 3 formulations with HA/TCP (60%/40%) granules (Straumann Bone Ceramic, Institut Straumann AG, Basel, Switzerland) yields a granular putty with similar application properties as those of the formulation of example 1.
Example 3
[0087] A 0.1 M aqueous solution of triethanolamine was brought to pH 8.7 using 2 M hydrochloric acid. 4-arm PEG-acrylate 15 k and HS-PEG-SH 3.4 k (both from Nektar, Huntsville, Ala., USA) were dissolved in this buffer solution, such that the total PEG concentration was 9.8 wt % and equimolar amounts of acrylate and thiol groups were present. Half of the solution was mixed with HA/TCP (60%/40%) granules in a ratio of 0.6 ml liquid per 0.5 g granules. From both the PEG solution and the mixture of PEG solution with granules, 6 cylindrical gels with a diameter of 6 mm were cast using stainless steel molds. After curing for 15 min, the gels were weighed, added to a Falcon tube containing 10 ml of 30 mM PBS (pH 7.4) and placed in a water bath at 37° C. At regular intervals the gels were taken from the buffer solution, blotted dry, and weighed. The pH of the buffer solution was checked and, if the value deviated by more than 0.1 from pH 7.4, the buffer was replaced by fresh 30 mM PBS (pH 7.4). The disintegration of the gels was followed by dividing their weight at each time point by the weight immediately after casting. Both the gels with and those without granules degraded at the same rate and had completely degraded within ca. 11 days ( FIG. 2 ), however, the addition of granules led to a markedly lower swelling.
[0088] FIG. 2 shows the swelling of the hydrogel samples (9.8 wt % PEG with/without granules) against time in PBS (pH 7.4) at 37° C. Average values of 6 samples (±SD) are given.
Example 4
Methods
[0089] 16 adult (12 months old) New Zealand White rabbits, weighing between 3 and 4 kg, were anesthetized and obtained each 4 titanium cylinders of 7 mm in height and 7 mm in outer diameter, which were screwed in 1 mm deep circular perforated slits made in the cortical bones of the calvaria. The following 4 treatment modalities were randomly allocated: (1) empty control, (2) a combination of PEG matrix and hydroxyapatite (HA)/tricalciumphosphate (TCP) granules (Straumann Bone Ceramic; Institut Straumann AG, Basel, Switzerland), and a combination of PEG matrix containing either 100 (3) or 20 μg/g gel (4) of PTH 1-34 and HA/TCP granules. Immediately before application, 4-arm PEG-acrylate 15 k and HS-PEG-SH 3.4 k (both from Nektar, Huntsville, Ala., USA) were each dissolved in a 0.1 M aqueous triethanolamine/HCl buffer (pH 8.7), such that the total PEG concentration in both solutions together was 9.8 wt % and equimolar amounts of acrylate and thiol groups were present. Both PEG solutions were then sterile filtered. For the activated gels, a 35 amino acid peptide of the parathyroid hormone (cys-PTH 1-34 ) and a 9 amino acid cys-RGD peptide (both from Bachem, Bubendorf, Switzerland) were additionally added to the PEG-acrylate solution, resulting in the formation of covalent bonds between the cystein-residues and the PEG-acrylate. The final concentrations for the peptides were 350 μg/g gel for cys-RGD and 20 or 100 μg/g gel for cys-PTH 1-34 .
[0090] The PEG solutions were then applied onto the HA/TCP granules and mixed for about 10 seconds. Subsequently, this granular putty was applied into the determined cylinders. Within 60 seconds, the PEG gels set and thus stabilized the HA/TCP granules. The cylinders were left open towards the bone side but were closed with a titanium lid towards the covering skin-periosteal flap. The periosteum and the cutaneous flap were adapted and sutured for primary healing.
[0091] After 8 weeks, the animals were sacrificed and ground sections were prepared for histology.
[0092] The bone formation in the cylinders was evaluated histologically. Mean values and standard deviations were calculated for the amounts of bone formation within the cylinders, either evaluated by the point measurements or by the area of bone regeneration and for the graft to bone contact. For statistical analysis, repeated measures ANOVA and subsequent pairwise Student's t-test with corrected p-values according to Holm's were used to detect the differences between the 4 treatment modalities.
Results
[0093] All animals showed uneventful healing of the area of surgery and no reductions in body weights were noted. Upon specimen retrieval, 3 cylinders were dislocated from the skull bone because of loss of fixation and were embedded in soft connected tissue. These 3 cylinders, 2 test sites and one control site, were excluded from further analysis. The remaining 61 cylinders were found to be stable and in the same position as at placement.
[0094] Qualitative histological evaluation revealed varying amounts of newly formed bone with no signs of inflammation in all cylinders. In the empty control cylinders, the augmented tissue comprised of slender bone trabeculae and large marrow spaces. The bone trabeculae adjacent to the surface of the inner wall of the cylinders were oriented parallel to and in various degrees of intimate contact with the surface of the machined cylinders.
[0095] The amount of newly formed bone within the control cylinders containing the unfunctionalized PEG matrix and the HA/TCP granules alone varied greatly. In contrast to the empty cylinders, the bone growth was not dominantly along the titanium walls and new bone was mostly in intimate contract with the granulate, which appeared intact and evenly distributed within the augmented tissue. In the upper third of the cylinders, the HA/TCP granules were mainly surrounded by non-mineralized tissue. In the two test groups, significantly more newly formed bone could be detected, partly reaching the upper third of the cylinder.
[0096] The area of bone regeneration on the sections of the cylinders was found to be as follows:
[0000]
Area of bone
regeneration
Condition
Number of samples
Mean (%)
SE
PEG-PTH 100
16
53.5
5.1
PEG-PTH 20
14
51.1
5.4
PEG
16
34.3
5.1
empty
15
23.2
5.2
[0097] FIG. 3 shows the areas of bone regeneration for the different treatments as well as the significance levels. From these data, it is concluded that the combination of a granulate and a polyethylene glycol hydrogel containing a covalently bound peptide of the parathyroid hormone combined with HA/TCP granules significantly stimulates in situ bone augmentation in rabbits.
[0098] Specifically, FIG. 3 shows the area of bone regeneration for the rabbit cranial cylinder model applying granules with PEG. Values are displayed as box-plots ranging from the 25 th to the 75 th quantiles, including the median and whiskers extending 1.5 times the interquartile range.
Example 5
Methods
[0099] 8 adult (12 months old) New Zealand White rabbits, weighing between 3 and 4 kg, were anesthetized and obtained each 4 titanium cylinders of 7 mm in height and 7 mm in outer diameter, which were screwed in 1 mm deep circular perforated slits made in the cortical bones of the calvaria. The following 4 treatment modalities were randomly allocated: (1) empty control, (2) a combination of PEG matrix containing 0.31 mg/ml covalently bound RGD and hydroxyapatite (HA)/tricalciumphosphate (TCP) granules (Straumann Bone Ceramic; Institut Straumann AG, Basel, Switzerland), and a combination of PEG matrix containing 0.31 mg/ml covalently bound RGD and either 15 μg (3) or 30 μg (4) of non-bound recombinant BMP-2 and HA/TCP granules.
[0100] Immediately before application, 4-arm PEG-acrylate 15 k and HS-PEG-SH 3.4 k (both from Nektar, Huntsville, Ala., USA) were dissolved in 2 mM aqueous HCl solution to yield a homogeneous solution containing equimolar numbers of acrylate and thiol groups, which was then sterile filtered. Aliquots of the sterile PEG solution, a solution of a 9 amino acid cys-RGD peptide (Bachem, Bubendorf, Switzerland), and a BMP-2 solution were combined with a 0.4 M triethanolamine/HCl buffer (pH 8.85) to yield 204 μl of a solution containing 9.8 wt % PEG, 0.31 mg/ml RGD, and 0, 74, or 147 μg/ml BMP-2. This solution was then applied onto 150 mg of HA/TCP granules and mixed for about 10 seconds. Subsequently, this granular putty was applied into the determined cylinders. Within 60 seconds, the PEG gels set and thus stabilized the HA/TCP granules. The cylinders were left open towards the bone side but were closed with a titanium lid towards the covering skin-periosteal flap. The periosteum and the cutaneous flap were adapted and sutured for primary healing.
[0101] After 8 weeks, the animals were sacrificed and ground sections were prepared for histology.
[0102] The bone formation in the cylinders was evaluated histologically. Mean values and standard deviations were calculated for the amounts of bone formation within the cylinders, either evaluated by the point measurements or by the area of bone regeneration.
Results
[0103] All animals showed uneventful healing of the area of surgery and no reductions in body weights were noted.
[0104] The area percentages of mineralized bone on the sections of the cylinders were found to be as follows:
[0000]
Mineralized
bone
Condition
Number of samples
Mean (%)
SD
PEG-BMP 30 μg
10
30.2
7.6
PEG-BMP 15 μg
10
25.0
7.9
PEG
10
15.2
8.0
empty
9
13.9
5.7
[0105] FIG. 4 shows the area percentages of bone regeneration for the different treatments as well as the significance levels. From these data, it is concluded that the combination of a granulate and a polyethylene glycol hydrogel containing a covalently bound RGD peptide and entrapped BMP-2, combined with HA/TCP granules significantly stimulates in situ bone augmentation in rabbits.
[0106] Specifically FIG. 4 shows the percentages of mineralized bone found for the rabbit cranial cylinder model applying granules with PEG. Values are displayed as box-plots ranging from the 25 th to the 75 th quantiles, including the median and whiskers extending 1.5 times the interquartile range. | Composition comprising a granulate selected from the group consisting of autogenous bone material, bone/bone like material from natural sources, synthetic materials and mixtures thereof and a matrix obtainable by a self selective reaction of at least two precursors A and B in the presence of water. A kit for preparing said composition is also described. | 0 |
This application claims the benefit of U.S. Provisional Application Ser. No. 60/043,138, filed Apr. 14, 1997.
BACKGROUND OF THE INVENTION
Torque wrenches are well-known devices to insure the accuracy of tightening a bolt or nut. They generally have a head, a handle, an internal spring in the handle and external adjustment means. The range of adjustment is usually limited by the spring. Any drastic changes in the range of the torque wrench are difficult to make and, as a practical matter, impossible for the average user. They are relatively expensive and difficult to manufacture.
This invention solves the problems of the prior art by making a simple inexpensive, adjustable torque wrench. The torque wrench of this invention includes a head, a handle attached to the head and a pivoted grip which fits over the handle. A main spring is placed near the end of the handle and is located between the grip and the handle. The main spring may be readily changed since it is accessible without any other disassembly. The main spring itself may be moved toward and away from the handle or simply replaced and thus adds a large degree of adjustability. Located between the main spring and the pivot on the grip is a clicker spring. The clicker spring is mounted in a slot on either the handle or the grip. It moves within a slot and is easily adjustable. Movement of the clicker spring toward and away from the head changes the torque setting at which the clicker spring makes a noise indicating the proper torque has been reached.
SUMMARY OF THE INVENTION
A torque wrench having a head, a handle attached thereto and a pivoted grip over the handle. A replaceable and moveable main spring is mounted between the handle and the grip at a position near the end of the handle. A clicker spring is moveable within a slot in the grip or the handle and is located therebetween. The clicker spring is positioned between the main spring and the pivot of the grip with the handle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the torque wrench of this invention;
FIG. 2 is a top view of FIG. 1;
FIG. 2A is an enlargement of part of FIG. 2;
FIG. 2B is an alternate of FIG. 2A;
FIG. 3 is a view 3--3 of FIG. 2;
FIG. 4 is a view 4--4 of FIG. 2; and
FIGS. 5 and 6 are a top view of FIG. 1 in partial cross section showing the relative motion of the parts.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A torque wrench 10 includes a head 12, a handle 14 and a grip 16. The head 12 has a conventional design with a reversing mechanism governed by the position of a selector 18. A removable socket is typically attached to head 12 to grasp a nut or bolt.
The handle 14 is shown as a bar with a rectangular cross-section. However, it may be any shape well known in the art such as tubular with varying diameters.
A channel-shaped grip 16 is sized to fit over the handle 14. The front part of the grip 16 has downwardly projecting tabs 22 through which pivotable fasteners 24 (only one shown) are placed to secure it rotatably to the handle 14. The fasteners 24 may be any known devices such as shafts, bolts, screws, pins or other devices for securely fastening one end of the grip 16 to the handle 14 while permitting their relative rotation while pivoting freely without binding. The tabs 22 are not absolutely necessary. The apertures for the fastener 24 could be placed in the main body of the grip 16. Tabs 17 limit the maximum opening of the grip 16 from the handle 14.
A main spring 26 is positioned near the end of the grip 16 which is opposite the pivotable fastener(s) 24. The main spring 26 may be a coiled spring, leaf spring or other resilient member that is compressible in a predictable, repeatable, measurable manner. At least one end of the main spring 20 must be fastened to the grip or handle and be positioned between them. Preferably one end 28 of the main spring 26 is fastened to the handle 14. In this manner, the grip 16 would remain in proximity to the handle 14 and swing from the fastener(s) 24. The strength of the main spring 26 would be selected as the primary force to be overcome in the use of this torque wrench. Its actual strength would be selected according to its intended use. It is well known that the force (F S ) in a spring is equal to a constant (k S ) multiplied by the distance it deflects (X 1 ), or otherwise moves (FIG. 5). Thus for F S =K S X 1 , K is typically selected to create a force F from one pound to three hundred pounds although others could be used.
F 1 and D 1 are shown at a typical average place where the force F 1 occurs. The force actually is spread over the width of the user's hand. A four inch length of the handle is a Military Standard.
It is an advantage of this invention that the main spring 26 could be changed for different uses. This easy interchangeability of main spring 26 gives this invention a versatility heretofore unknown. It is only necessary to unscrew or otherwise release the end(s) of the main spring 26 by means of a fastener 32 (FIGS. 2 and 2A) remove it and replace it with one of a different strength or constant (k).
It is also within the scope of this invention to allow the main spring 26 to be slideable along the length of the grip 16 and handle 14. It is only necessary to loosen the fastener 32, slide the spring 26 along the slot 27 and tightening the fastener 32. This variation would cause a change in the distance (D 2 ) (FIG. 5) and thus the torque T 1 . T 1 is generated by the force F 1 (FIG. 5) multiplied by the distance D 1 or T 1 =F 1 D 1 . This must also equal the force of the spring Fs multiplied by D 2 thus F 1 D 1 =F S D 2 Variations of the force and thus the torque can be made by allowing the main spring 26 to move along the length of the handle 14 (FIGS. 4 and 5). As the main spring 26 moves closer to the head, the force F S required to compress it will increase if the user grasps the same point on the grip. Since F 1 D 1 =F S D 2 in equilibrium, as the distance D 2 is reduced, Fs must increase before the clicker is actuated.
Fine adjustments and a clicking noise are supplied by a clicker spring 34 (FIG. 2A and 2B) having one end 35 mounted in a clicker block 36 slideably mounted in the grip 16 on handle 14. The other end of the clicker spring 34 engages the opposite piece 14. The clicker spring 34 is normally made of spring steel and shaped to make a clicking noise when it is bent to a preselected position. Other noise makers may also be provided if they do so at a consistent preselected position and/or force. The clicker spring is basically a leaf spring but it may have other shapes such as a coil. The clicker spring normally does not take a significant force to bend relative to the main spring 26. Such force is usually less than a few pounds. However, it may also be changed to provide a different range of forces. The clicker may also be preloaded to a certain force by compression between the grip and handle before the main spring 26 is compressed.
FIG. 2B illustrates an alternate of FIG. 2A and the same numbers are used for similar parts. In this embodiment, the main spring 26 is supported between the grip 16 and a flared base 55 in the handle 14. This allows greater deflection of the main spring 26. The clicker spring 34 is attached to the handle by the same mechanism as FIG. 2A and is moveable in a slot 42. The advantage of the embodiment is that the clicker mount does not interfere with the grip. FIG. 2B further illustrates a hand locator 41 with upwardly turned flanges 43 and 45. It is adhered or fastened to the grip 16. The hand locator is usually about 4" long since that is an accepted standard. The flanges 43 and 45 not only ensure correct placement of the hand but also reduces slippage of the hand. Correct hand placement assures greater accuracy of the torque wrench. That is, the average force location F 1 will constantly be at or near the center of the grip 41. The grip 41 could also be used on the other embodiments herein.
A locking screw 40 or other fastener is attached to and holds the clicker block 36 to the grip 16 or to the handle 14. A slot 42 in the grip 16 through which the locking screw 40 passes allows movement of the clicker block 36 and clicker spring 34 along the length of the handle 14. As shown in FIG. 5, the clicker 34 will make a noise when the main spring deflects a distance X 1 which represents a force F 1 on the main spring 26. F 1 in FIG. 5 is generally the maximum force possible with a given main spring in a given location. Thus, when the clicker spring 34 is closest to the head, the maximum force must be used.
The minimum force F 1 for a given position of main spring 24 is set on the torque wrench by moving the clicker spring to a position closest to the main spring 26 (FIG. 6). In this position, a relatively small movement of the grip 16 causes a deflection X 2 to activate the clicker 34. This occurs simply because of the geometry of the grip being pivoted at 24. The closer the clicker spring 34 is to pivot 24, the more the main spring 26 has to be compressed and the greater the force F has to be before the click is heard. The positions of the clicker spring 34 would normally be calibrated between those shown in FIGS. 5 and 6.
It is also anticipated that a coil or loop spring could be placed at the pivot 24 and work in a similar manner. One end of the coil spring would engage the handle 14, the other end would engage the grip 16 and the pivot 24 would be in its center. A leaf spring could also replace the main coil spring 26 at about the same location.
Many different sizes and torque ranges are possible. One embodiment found useful utilizes a torque arm length of approximately 12". The torque arm length is the distance from the drive socket to the center of the grip. The main spring 26 may be made of music wire having a diameter of 0.060" formed in 10 active coils having an inner diameter of 0.315" and a free height of about 1.1" and a compressed height of about 0.72". These components produce a torque in the range of about 25 pounds. Obviously there will be a range involved.
This invention, because of its ingenious simplicity is not only very versatile but much less complex, has fewer working parts and is less expensive to manufacture than the prior art. It can be calibrated over a wide range of torques and such range may be changed. Other torque wrenches have enclosed parts which make them much harder to disassemble for repair or alteration.
The present disclosure describes several embodiments of the invention, however, the invention is not limited to these embodiments. Other variations are contemplated to be within the spirit and scope of the invention and appended claims. | An audible torque wrench including a head having a tool connecting part. A handle is operatively attached to the head in order to cause rotation thereof. A grip is pivotably attached at one of its ends to the handle. A spring is fastened between the grip and the handle at the end opposite the pivot on the grip. The spring is mounted so that it may be moved longitudinally along the length of the handle in order to change the torque settings for the wrench. An audible clicker spring is fastened to either the handle or the grip at a position between them so that when a force is applied to the grip, to rotate it about the head, the grip compresses the spring and biases the resilient member until it reaches the position where an audible signal is made. | 1 |
BACKGROUND OF THE INVENTION
[0001] (1) Field of the Invention
[0002] This invention relates to a layout and method to improve linearity and reduce voltage coefficient of resistance for resistors used in mixed-mode analog/digital applications.
[0003] (2) Description of the Related Art
[0004] U.S. Pat. No. 6,103,622 to Huang describes a silicide process for mixed-mode analog digital/devices.
[0005] U.S. Pat. No. 5,924,011 to Huang describes a method for fabricating mixed analog/digital devices using a silicide process.
[0006] U.S. Pat. No. 6,054,359 to Tsui et al. describes a method for fabricating high sheet resistance polysilicon resistors.
[0007] U.S. Pat. No. 5,885,862 to Jao et al. describes a poly-load resistor for a static random access memory, SRAM, cell.
[0008] A paper entitled “Characterization of Polysilicon Resistors in Sub-0.25 μm CMOS USLI Applications” by Wen-Chau Liu, Member IEEE, Kong-Beng Thei, Hung-Ming Chuang, Kun-Wei Lin, Chin-Chuan Cheng, Yen-Shih Ho, Chi-Wen Su, Shyh-Chyi Wong, Chih-Hsien Lin, and Carlos H. Diaz, IEEE Electron Device Letters, Vol. 22, No. 7, pages 318-320, July 2001 describes characterization of polysilicon resistors.
SUMMARY OF THE INVENTION
[0009] High performance resistors are important devices in the design of mixed-mode analog/digital circuits. A number of parameters are of key importance for these resistors such as resistor linearity, insensitivity of resistance to thermal processing steps, and voltage coefficient of resistance (VCR).
[0010] It is a principal objective of at least one embodiment of this invention to provide a method of forming a resistor having good linearity, thermal process stability, and low voltage coefficient of resistance (VCR).
[0011] It is another principal objective of at least one embodiment of this invention to provide a resistor layout for a resistor having good linearity, thermal process stability, and low voltage coefficient of resistance (VCR).
[0012] These objectives are achieved by first forming a resistor from a first conducting material such as doped polysilicon. The resistor has a rectangular first resistor element having a width, a length, a first end, and a second end; a second resistor element having a first edge and a second edge wherein the first edge of the second resistor element contacts the entire width of the first end of the first resistor element; a third resistor element having a first edge and a second edge wherein the first edge of the third resistor element contacts the entire width of the second end of the first resistor element; a fourth resistor element having a contact edge wherein the contact edge of the fourth resistor element contacts the entire the second edge of the second resistor element; and a fifth resistor element having a contact edge wherein the contact edge of the fifth resistor element contacts the entire the second edge of the third resistor element. A layer of protective dielectric is then formed over the first, second, and third resistor elements leaving the fourth and fifth resistor elements exposed.
[0013] The first conducting material in the exposed fourth and fifth resistor elements is then changed to a second conducting material, which is a silicide, using a silicidation process. The second conducting material is a silicide such as titanium silicide. The second conducting material has a higher conductivity than the first conducting material. The higher conductivity second conducting material forms low resistance contacts between the second and fourth resistor elements and between the third and fifth resistor elements. The second and third resistor elements are wider than the first resistor element and provide a low resistance contacts to the first resistor element, which is the main resistor element. This provides low voltage coefficient of resistance and good resistor linearity.
[0014] The protective dielectric over the first, second, and third resistor elements prevents the resistor from silicidation during subsequent process steps.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 shows a top view of one embodiment of the resistor of this invention before the protective dielectric layer has been formed.
[0016] [0016]FIG. 2 shows a cross section view of the resistor of FIG. 1 taken along line 2 - 2 ′ of FIG. 1.
[0017] [0017]FIG. 3 shows a top view of the embodiment of the resistor of this invention shown in FIG. 1 after the protective dielectric layer has been formed.
[0018] [0018]FIG. 4 shows a cross section view of the resistor of FIG. 3 taken along line 4 - 4 ′ of FIG. 3.
[0019] [0019]FIG. 5 shows a top view of another embodiment of the resistor of this invention before the protective dielectric layer has been formed.
[0020] [0020]FIG. 6 shows a top view of the embodiment of the resistor of this invention shown in FIG. 5 after the protective dielectric layer has been formed.
[0021] [0021]FIG. 7 shows a top view of another embodiment of the resistor of this invention before the protective dielectric layer has been formed.
[0022] [0022]FIG. 8 shows a cross section view of the resistor of FIG. 7 taken along line 8 - 8 ′ of FIG. 7.
[0023] [0023]FIG. 9 shows a top view of the embodiment of the resistor of this invention shown in FIG. 8 after the protective dielectric layer has been formed.
[0024] [0024]FIG. 10 shows a cross section view of the resistor of FIG. 9 taken along line 10 - 10 ′ of FIG. 9.
[0025] [0025]FIG. 11 shows a top view of another embodiment of the resistor of this invention after the protective dielectric layer has been formed.
[0026] [0026]FIG. 12 shows resistance as a function of voltage for a P + doped polysilicon resistor having the protective dielectric layer of this invention and a P + doped polysilicon resistor, having the same doping level, without the protective dielectric layer.
[0027] [0027]FIG. 13 shows resistance as a function of voltage for an N + doped polysilicon resistor having the protective dielectric layer of this invention and an N + doped polysilicon resistor, having the same doping level, without the protective dielectric layer.
[0028] [0028]FIG. 14 shows the voltage coefficient of resistance as a function of voltage for a P + doped polysilicon resistor having the protective dielectric layer of this invention and a P + doped polysilicon resistor, having the same doping level, without the protective dielectric layer.
[0029] [0029]FIG. 15 shows the voltage coefficient of resistance as a function of voltage for an N + doped polysilicon resistor having the protective dielectric layer of this invention and an N + doped polysilicon resistor, having the same doping level, without the protective dielectric layer.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] Refer now to the drawings for a detailed description of the preferred embodiments of this invention. FIG. 1 shows a top view of a resistor having a first resistor element 120 , a second resistor element 130 , a third resistor element 170 , a fourth resistor element 150 , and a fifth resistor element 190 . The resistor is formed on a substrate 100 , such as a silicon substrate having devices formed therein. FIG. 2 shows a cross section of the resistor at this stage of fabrication taken along line 2 - 2 ′ of FIG. 1. The boundaries between the first 120 and second 130 resistor elements, the first 120 and third 170 resistor elements, the second 130 and fourth 150 resistor elements, and the third 170 and fifth 190 resistor elements are shown by dashed lines in FIGS. 1 and 2. The resistor is formed of a patterned layer of conducting material. The conducting material can be doped polysilicon doped with either N type impurities or P type impurities. As shown in FIG. 1, the first resistor element 120 is a rectangle having a length 20 , a width 22 , a first end 21 , and a second end 23 . The polysilicon is deposited, patterned, and doped using techniques well known to those skilled in the art.
[0031] The resistance of the resistor is primarily determined by the resistance of the first resistor element 120 , as will be described in greater detail later. The resistance of the first resistor element is determined by the doping of the polysilicon, which determines the conductivity of the polysilicon, the length 20 of the first resistor element 120 , and width 22 of the first resistor element 120 .
[0032] As shown in FIGS. 3 and 4, a layer of protective dielectric 140 is deposited and patterned to cover the first 120 , second 130 , and third 170 resistor elements. The fourth 150 and fifth 190 resistor elements are not covered by the protective dielectric 140 . The protective dielectric can be an oxide, such as silicon oxide, or silicon nitride deposited and patterned using techniques well known to those skilled in the art.
[0033] Next a silicidation process, well known to those skilled in the art, is carried out which converts the conducting material in the fourth 150 and fifth 190 resistor elements to a silicide. In this example the conducting material of polysilicon in the fourth 150 and fifth 190 resistor elements is converted to a silicide such as titanium silicide, cobalt silicide, or the like. As those skilled in the art will readily recognize the silicidation process is usually part of the process for forming contacts in other regions of the substrate 100 . The protective dielectric 140 protects the first 120 , second 130 , and third 170 resistor elements from the silicidation process so that the first conducting material remains unchanged and the conductivity of the conducting material forming the first 120 , second 130 , and third 170 resistor elements remains unchanged. The protective dielectric 140 also protects the conducting material forming the first 120 , second 130 , and third 170 resistor elements from subsequent process steps so that the conductivity of the conducting material in these regions is not changed. Contacts 24 to the resistor can be formed in the fourth 150 and fifth 190 resistor elements using methods well known to those skilled in the art.
[0034] The conductivity of the silicide in the fourth 150 and fifth 190 resistor elements is substantially greater than the conductivity of the conducting material in the first 120 , second 130 , and third 170 resistor elements. The resistance of the interface 18 between the second resistor element 130 and the interface 16 between the third 170 and fifth 190 resistor elements is low compared to the resistance of the first resistor element 120 because the conducting material forming the fourth 150 and fifth 190 resistor elements has been converted to a silicide. The second 130 and third 170 resistor elements are designed to be wide relative to the width 22 of the first 120 resistor element so their resistance will be small compared to the first 120 resistor element.
[0035] The resistance, R, of the resistor can be expressed as R=R 1 +2 R 2 +2 R 3 +2 R 4 +R 5 . In this equation R 1 is the resistance of the first 120 resistor element, R 2 is the resistance of the contacts 24 to the fourth 150 and fifth 190 resistor elements, R 3 is the resistance of the fourth 150 and fifth 190 resistor elements, R 4 is the resistance of interfaces, 18 and 16 , between the second 130 and fourth 150 resistor elements and between the third 170 and fifth 190 resistor elements, and R 5 is the resistance of the second 130 and third 170 resistor elements. Of these resistances R 2 , R 3 , R 4 , and R 5 are all quite small with respect to R 1 , and the resistance, R, of the resistor is very nearly equal to R 1 . This makes it possible to accurately adjust the resistance of the resistor by controlling the doping of the polysilicon, the length 20 of the first resistor element 120 , and the width 22 of the first resistor element 120 .
[0036] Another embodiment of the resistor layout of this invention is shown in FIGS. 5 and 6. As shown in FIGS. 5 and 6 dummy resistor elements 26 can be formed on either side of the first resistor element 120 . The dummy resistor elements 26 can be used to compensate for proximity effects when the dimensions of the first resistor element 120 are very small. FIG. 5 shows the resistor before the protective dielectric layer 140 is formed. FIG. 6 shows the resistor after the protective dielectric layer 140 is formed.
[0037] [0037]FIGS. 7-11 show another embodiment of the resistor layout and method of this invention. FIG. 7 shows the top view of a resistor and FIG. 8 a cross section taken along line 8 - 8 ′ of FIG. 7. As in the preceding embodiments, the resistor has a first resistor element 32 , a second resistor element 33 , a third resistor element 37 , a fourth resistor element 35 , and a fifth resistor element 39 . In this embodiment, as can be seen in FIG. 8, the resistor is formed within the substrate 30 and at the top surface of the substrate. In this embodiment the first 32 , second 33 , third 37 , fourth 35 , and fifth 39 resistor elements can be formed by a patterned deposition of impurities in a silicon substrate 30 using techniques well known to those skilled in the art. In this embodiment the first 32 , second 33 , third 37 , fourth 35 , and fifth 39 resistor elements can be formed by deposition of N or P type impurities in a silicon substrate 30 .
[0038] As shown in FIGS. 9 and 10, a layer of protective dielectric 34 is deposited and patterned to cover the first 32 , second 33 , and third 37 resistor elements. The fourth 35 and fifth 39 resistor elements are not covered by the protective dielectric 34 . The protective dielectric can be an oxide such as silicon oxide deposited and patterned using techniques well known to those skilled in the art.
[0039] Next a silicidation process, well known to those skilled in the art, is carried out which converts the conducting material in the fourth 35 and fifth 39 resistor elements to a silicide. In this example with the conducting material of silicon the conducting material in the fourth 35 and fifth 39 resistor elements can be converted to a silicide such as titanium silicide, cobalt silicide, or the like. As those skilled in the art will readily recognize the silicidation process is usually part of the process for forming contacts in other regions of the substrate 30 . The protective dielectric 34 protects the first 32 , second 33 , and third 37 resistor elements from the silicidation process so that the first conducting material remains unchanged and the conductivity of the conducting material forming the first 32 , second 33 , and third 37 resistor elements remains unchanged. The protective dielectric 34 also protects the conducting material forming the first 32 , second 33 , and third 37 resistor elements from subsequent process steps so that the conductivity of the conducting material in these regions is not changed. Contacts 34 to the resistor can be formed in the fourth 35 and fifth 39 resistor elements using methods well known to those skilled in the art.
[0040] The conductivity of the silicide in the fourth 35 and fifth 39 resistor elements is substantially greater than the conductivity of the conducting material in the first 32 , second 33 , and third 37 resistor elements. The resistance of the interface 38 between the second resistor element 33 and the interface 36 between the third 37 and fifth 39 resistor elements is low compared to the resistance of the first resistor element 32 because the conducting material forming the fourth 35 and fifth 39 resistor elements has been converted to a silicide. The second 33 and third 37 resistor elements are designed to be wide relative to the width 42 of the first 32 resistor element so their resistance will be small compared to the first 32 resistor element.
[0041] The resistance, R, of the resistor can be expressed as R=R 1 +2 R 2 +2 R 3 +2 R 4 +R 5 . In this equation R 1 is the resistance of the first 32 resistor element, R 2 is the resistance of the contacts 44 to the fourth 35 and fifth 39 resistor elements, R 3 is the resistance of the fourth 35 and fifth 39 resistor elements, R 4 is the resistance of interfaces, 38 and 36 , between the second 33 and fourth 35 resistor elements and between the third 37 and fifth 39 resistor elements, and R 5 is the resistance of the second 33 and third 37 resistor elements. Of these resistances R 2 , R 3 , R 4 , and R 5 are all quite small with respect to R 1 , and the resistance, R, of the resistor is very nearly equal to R 1 . This makes it possible to accurately adjust the resistance of the resistor by controlling the doping of the silicon, the length 40 of the first resistor element 32 , and the width 42 of the first resistor element. In addition to providing the ability to accurately design the resistance of the resistor, the protective dielectric keeps the resistance stable throughout subsequent processing. The design and methods of this invention provides a resistor having a low voltage coefficient of resistance (VCR).
[0042] Another embodiment of the resistor layout of this invention is shown in FIG. 11. As shown in FIG. 11 dummy resistor elements 46 can be formed on either side of the first resistor element 32 . The dummy resistor elements 46 can be used to compensate for proximity effects when the dimensions of the first resistor element 32 are very small. FIG. 6 shows the resistor with dummy resistor elements 46 after the protective dielectric layer 34 has been formed.
[0043] The improvement of resistor characteristics due to the protective dielectric layer of this invention is shown in FIGS. 12-15. FIG. 12 shows a first curve 70 and a second curve 72 . The first curve 70 shows resistance as a function of voltage for a P+ doped polysilicon resistor having the protective dielectric layer of this invention. The second curve 72 shows resistance as a function of voltage for a P+ doped polysilicon resistor having the same doping level but without the protective dielectric layer.
[0044] [0044]FIG. 13 shows a third curve 71 and a fourth curve 73 . The third curve 71 shows resistance as a function of voltage for an N + doped polysilicon resistor having the protective dielectric layer of this invention. The fourth curve 73 shows resistance as a function of voltage for an N + doped polysilicon resistor having the same doping level but without the protective dielectric layer.
[0045] [0045]FIG. 14 shows a fifth curve 74 and a sixth curve 76 . The fifth curve 74 shows the voltage coefficient of resistance as a function of voltage for a P + doped polysilicon resistor having the protective dielectric layer of this invention. The sixth curve 76 shows the voltage coefficient of resistance as a function of voltage for a P + doped polysilicon resistor having the same doping level but without the protective dielectric layer.
[0046] [0046]FIG. 15 shows a seventh curve 75 and a eighth curve 77 . The seventh curve 75 shows the voltage coefficient of resistance as a function of voltage for an N + doped polysilicon resistor having the protective dielectric layer of this invention. The eighth curve 77 shows the voltage coefficient of resistance as a function of voltage for an N + doped polysilicon resistor having the same doping level but without the protective dielectric layer.
[0047] While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention. | A resistor layout and method of forming the resistor are described which achieves improved resistor characteristics, such as resistor stability and voltage coefficient of resistance. A resistor is formed from a conducting material such as doped silicon or polysilicon. The resistor has a rectangular first resistor element, a second resistor element, a third resistor element, a fourth resistor element, and a fifth resistor element. A layer of protective dielectric is then formed over the first, second, and third resistor elements leaving the fourth and fifth resistor elements exposed. The conducting material in the exposed fourth and fifth resistor elements is then changed to a silicide, such as titanium silicide or cobalt silicide, using a silicidation process. The higher conductivity silicide forms low resistance contacts between the second and fourth resistor elements and between the third and fifth resistor elements. The second and third resistor elements are wider than the first resistor element and provide a low resistance contacts to the first resistor element, which is the main resistor element. This provides low voltage coefficient of resistance thermal process stability for the resistor. | 8 |
This is a division of patent application Ser. No. 10/104,802, filing date Mar. 22, 2002, now U.S. Pat. No. 6,857,180, Transverse Or Longitudinal Patterned Synthetic Exchange Biasing For Stabilizing Gmr Sensors, assigned to the same assignee as the present invention, which is herein incorporated by reference in its entirety.
RELATED PATENT APPLICATION
This application is related to Ser. No. 10/091,959 filing date Mar. 6, 2002, now U.S. Pat. No. 7,035,060, Ser. No. 10/077,064, filing date Feb. 15, 2002, now U.S. Pat. No. 7,010,848, and Ser. No. 10/116,984, filing date Apr. 15, 2002, now U.S. Pat. No. 6,842,969, assigned to the same assignee as the current invention.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to the fabrication of a giant magnetoresistive (GMR) magnetic field sensor for a magnetic read head, more specifically to the use of either transverse or longitudinal synthetic exchange biasing to stabilize, suppress side reading and reduce the magnetic track width (MRW) of such a sensor.
2. Description of the Related Art
Magnetic read heads whose sensors make use of the giant magnetoresistive effect (GMR) in the spin-valve configuration (SVMR) base their operation on the fact that magnetic fields produced by data stored in the medium being read cause the direction of the magnetization of one layer in the sensor (the free magnetic layer) to move relative to a fixed magnetization direction of another layer of the sensor (the fixed or pinned magnetic layer). Because the resistance of the sensor element is proportional to the cosine of the (varying) angle between these two magnetizations, a constant current (the sensing current) passing through the sensor produces a varying voltage across the sensor which is interpreted by associated electronic circuitry. The accuracy, linearity and stability required of a GMR sensor places stringent requirements on the magnetization of its fixed and free magnetic layers. The fixed layer, for example, has its magnetization “pinned” in a direction normal to the air bearing surface of the sensor (the transverse direction) by an adjacent magnetic layer (typically an antiferromagnetic layer) called the pinning layer. The free layer is typically magnetized in a direction along the width of the sensor and parallel to the air bearing surface (the longitudinal direction). Layers of hard magnetic material (permanent magnetic layers) or laminates of antiferromagnetic and soft magnetic materials are typically formed on each side of the sensor and oriented so that their magnetic field extends in the same direction as that of the free layer. These layers, called longitudinal bias layers, maintain the free layer as a single magnetic domain and also assist in linearizing the sensor response by keeping the free layer magnetization direction normal to that of the fixed layer when quiescent. Maintaining the free layer in a single domain state significantly reduces noise (Barkhausen noise) in the signal produced by thermodynamic variations in domain configurations. A magnetically stable spin-valve sensor using either hard magnetic biasing layers or ferromagnetic biasing layers is disclosed by Zhu et al. (U.S. Pat. No. 6,324,037 B1) and by Huai et al. (U.S. Pat. No. 6,222,707 B1).
The importance of longitudinal bias has led to various inventions designed to improve the material composition, structure, positioning and method of forming the magnetic layers that produce it. One form of the prior art provides for sensor structures in which the longitudinal bias layers are layers of hard magnetic material (permanent magnets) that abut the etched back ends of the active region of the sensor to produce what is called an abutted junction configuration. This arrangement fixes the domain structure of the free magnetic layer by magnetostatic coupling through direct edge-to-edge contact at the etched junction between the biasing layer and the exposed end of the layer being biased (the free layer). Another form of the present art employs patterned direct exchange bias. Unlike the magnetostatic coupling resulting from direct contact with a hard magnetic material that is used in the abutted junction, in exchange coupling the biasing layer is a layer of ferromagnetic material which overlays the layer being biased, but is separated from it by a thin coupling layer of conducting, but non-magnetic material. This non-magnetic gap separating the two layers produces exchange coupling between them, a situation in which it is energetically favorable for the biasing layer and the biased layer assume a certain relative direction of magnetization. Another form of exchange coupling involves a direct contact between the free ferromagnetic layer and an overlaying layer of antiferromagnetic material. Xiao et al. (U.S. Pat. No. 6,322,640 B1) disclose a method for forming a double, antiferromagnetically biased GMR sensor, using as the biasing material a magnetic material having two crystalline phases, one of which couples antiferromagnetically and the other of which does not. Fuke et al. (U.S. Pat. No. 6,313,973 B1) provides an exchange coupled configuration comprising a coupling film, an antiferromagnetic film and a ferromagnetic film and wherein the coupling film has a particularly advantageous crystal structure.
As the area density of magnetization in magnetic recording media (eg. disks) continues to increase, significant reduction in the width of the active sensing region (trackwidth) of read-sensors becomes necessary. For trackwidths less than 0.2 microns (μm), the traditional abutted junction hard bias structure discussed above becomes unsuitable because the strong magnetostatic coupling at the junction surface actually pins the magnetization of the (very narrow) biased layer (the free layer), making it less responsive to the signal being read and, thereby, significantly reducing the sensor sensitivity.
Under very narrow trackwidth conditions, the exchange bias method becomes increasingly attractive, since the free layer is not reduced in size by the formation of an abutted junction, but extends continuously across the entire width of the sensor element. FIG. 1 is a schematic depiction of an abutted junction arrangement and FIG. 2 is an equally schematic depiction of a direct exchange coupled configuration. As can be seen, the trackwidth in the abutted junction is made narrow by physically etching away both ends of the sensor, whereas in the exchange coupled sensor, the trackwidth is defined by placement of the conductive leads and bias layers while the sensor element retains its full width.
The direct exchange biasing-also has disadvantages when used in a very narrow trackwidth configuration because of the weakness of the pinning field, which is found to be, typically, approximately 250 Oe. The present invention will address this weak pinning field problem while retaining the advantages of exchange biasing by providing a new exchange biased configuration, synthetic exchange biasing. In this configuration, the biasing layer is exchange coupled to the free layer by antiferromagnetic exchange coupling, in which the ferromagnetic biasing layer and the ferromagnetic free layer are coupled by a non-magnetic layer to form a configuration in which the two layers have antiparallel magnetizations (a synthetic antiferromagnetic layer). A stronger pinning field, typically exceeding 700 Oe, can be obtained using the synthetic exchange biasing method. More advantageously, an effective magnetic trackwidth of 0.15 μm can be obtained with a physical track width of 0.1 μm by using such a configuration by reducing the level of side reading (sensor response generated by signals originating outside of the magnetic trackwidth region) which is produced by the portion of the free layer that is beneath the biasing layer and conduction leads. The invention provides such a novel synthetic exchange biased sensor in two configurations, longitudinal and transverse, each of which is shown to have particular advantages both in its operation and its formation.
SUMMARY OF THE INVENTION
It is a first object of the present invention to provide a magnetically stable patterned synthetic exchange biased GMR sensor capable of reading high area density magnetic recordings of densities exceeding 60 Gb/in 2 (gigabits per square inch).
It is a second object of the present invention to provide such a patterned synthetic exchange biased GMR sensor which is biased in either the longitudinal or the transverse directions.
It is a third object of the present invention to provide such a synthetic exchange biased GMR sensor having a very narrow effective magnetic trackwidth in which undesirable side reading is significantly reduced.
It is a fourth object of the present invention to provide such a synthetic exchange biased GMR sensor that is easily fabricated.
It is a fifth object of the present invention to provide such a synthetic exchange biased GMR sensor that has thin conducting lead layers for an improved topography.
The objects of this invention will be achieved in three embodiments, each of which will now be briefly described and will then be described in fuller detail below. In the first embodiment, a synthetic exchange longitudinally biased GMR sensor will be provided, said sensor having a bottom spin valve, specularly reflecting structure which can be deposited in a single fabrication process and which has the following structural form:
NiCr/MnPt/CoFe(AP2)/Ru/CoFe(AP1)/Cu/CoFe—NiFe/Ru/CoFe/IrMn/Ta/Au
The NiCr is a seed layer, the MnPt is an antiferromagnetic pinning layer for the bottom synthetic pinned layer of CoFe (AP2)/Ru/CoFe(AP1), wherein the two ferromagnetic exchange coupled CoFe layers are labeled AP1 & AP2 to distinguish them. The Cu layer is a conducting, non-magnetic spacer layer separating the synthetic pinned layer from the CoFe—NiFe ferromagnetic free layer (a bilayer). This latter bilayer is antiferromagnetically-exchange-coupled across a Ru layer to a (patterned) CoFe biasing layer, forming the synthetic exchange coupled bias structure which has both a high pinning field and advantageous magnetostriction characteristics. The exchange biased layer is itself antiferromagnetically pinned by direct exchange coupling with an antiferromagnetic IrMn layer, over which is a conductive lead layer of Ta/Au. It is found that the pinning field of the free layer provided by the patterned bias layer in this synthetic exchange coupled configuration exceeds 650 Oe and may be as high as 755 Oe, as compared to pinning fields of the order of 250–300 Oe for the direct (not synthetic) coupled structure.
In the second embodiment, a synthetic exchange transversely biased GMR sensor will be provided together with a method for its fabrication. The structural form of this embodiment is:
NiCr/AFM/CoFe(AP2)/Ru/CoFe(AP1)/Cu/CoFe—NiFe/Ru/CoFe/AFM/Ta/Au.
The NiCr is a seed layer, AFM denotes an antiferromagnetic pinning layer for the bottom synthetic pinned layer of CoFe (AP2)/Ru/CoFe(AP1), wherein the two ferromagnetic exchange coupled CoFe layers are labeled AP1 & AP2 to distinguish them. The Cu layer is a conducting, non-magnetic spacer layer separating the synthetic pinned layer from the CoFe—NiFe ferromagnetic free layer (a bilayer). This latter bilayer is antiferromagnetically exchange coupled across a Ru layer to a (patterned) CoFe biasing layer, forming the synthetic exchange coupled bias structure. The exchange biased layer is itself antiferromagnetically pinned by direct exchange coupling with an antiferromagnetic layer, again denoted AFM, over which is a conductive lead layer of Ta/Au. In contrast to the structural form of the first embodiment, the same antiferromagnetic material, typically either IrMn or MnPt, can serve in both locations designated AFM. An important advantage of the transverse biasing is that the magnetic field of the free and pinned layers are in the same direction, producing a plateau region under low external field wherein the free layer magnetization and the pinned layer magnetizations do not rotate relative to each other. This is particularly important for reducing signal contributions from the free layer region that is under the biasing layer which then produces a narrow effective trackwidth.
It is another one of the advantages of this second embodiment that different antiferromagnetic materials are not necessary to achieve its objects because both the synthetic pinned layer, CoFe (AP2)/Ru/CoFe(AP1), and the synthetic bias exchange coupled free layer, CoFe—NiFe/Ru/CoFe, are magnetized along the same direction. This allows antiferromagnetic materials with high blocking temperatures to be utilized which, in turn, allows high pinning fields to be obtained. The high pinning fields minimizes the problems caused by sensor current flow within the sensor element and, consequently, current shunting is not required and thin conducting lead layers can be used. The third embodiment of the present invention provides a transversely biased sensor as in the second embodiment, but the pinning fields at opposite ends of the free layer are antiparallel to each other. This configuration affords the additional advantages of stabilizing the bias point of the free layer and further minimizing side reading by the sensor. In the description of the three embodiments provided below, the structures, the processes preferred for their fabrication and their advantages, will be more fully described.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects, features and advantages of the present invention are understood within the context of the Description of the Preferred Embodiment, as set forth below. The Description of the Preferred Embodiment is understood within the context of the accompanying figures, wherein:
FIG. 1 is a highly schematic diagram of a prior-art abutted junction GMR sensor stack having a hard magnetic longitudinal bias layer and conductive lead overlayer in contact with the junction. The diagram is a cross-sectional view of the air bearing surface (ABS) of the sensor. The sensor stack shows only the free layer.
FIG. 2 is a schematic, ABS view, cross-sectional diagram of a prior-art direct exchange (longitudinally) biased GMR sensor stack, showing the patterned biasing layers, their magnetization directions, and other layers of the sensor.
FIG. 3 a is a schematic, ABS view, cross-sectional diagram of a synthetic exchange (longitudinally) biased GMR sensor stack, before patterning, fabricated in accord with the objects of the first preferred embodiment of the present invention.
FIG. 3 b shows the process of patterning the sensor of FIG. 3 a.
FIG. 4 a is a schematic, ABS view, cross-sectional diagram of a synthetic exchange biased GMR sensor stack formed in accord with a second embodiment of the present invention. The transverse magnetizations of the exchange biased free layer and the synthetic pinned layer are indicated.
FIG. 4 b is the sensor stack of FIG. 4 a subsequent to patterning.
FIG. 5 a is a schematic, ABS view, cross-sectional diagram of a partially formed synthetic exchange biased GMR sensor stack formed in accord with a third embodiment of the present invention. In this embodiment the transverse magnetizations of each lateral end of the exchange biased free layer are antiparallel to each other and each is also antiparallel to the transverse magnetizations of the biasing layers that overlay them.
FIGS. 5 b – 5 e show the detailed processes by which the sensor stack of 5 a is patterned and magnetized.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1 there is shown a schematic cross-sectional view of the ABS surface of a typical abutted junction GMR sensor designed in accord with the prior art. As can be seen, the narrow trackwidth is obtained at the price of reducing the physical width of the ferromagnetic free layer ( 10 ). As a result, the biasing layer ( 25 ) pins the magnetization of the free layer and reduces the sensitivity of the sensor.
Referring next to FIG. 2 , there is shown a schematic cross-sectional view of the ABS surface of a patterned direct exchange longitudinally biased GMR sensor of the prior art. The physical trackwidth ( 10 ) of this configuration is defined by the width of the region between the leads ( 20 ), typically a Ta/Au bilayer, and the patterned biasing layers beneath them ( 25 ), typically layers of CoFe: The ferromagnetic free layer ( 27 ), typically a CoFe/NiFe bilayer, extends the entire width of the sensor so it is not adversely affected by the edge pinning field of the biasing layer, which is a disadvantage of the hard biased abutted junction of FIG. 1 . The diagram also shows the antiferromagnetic layer ( 29 ), typically a layer of IrMn, which pins the patterned biasing layer ( 25 ). The free layer ( 27 ) is separated from the biasing layer ( 25 ) by a non-magnetic coupling layer ( 28 ) which is typically a layer of Cu or Ru and which directly exchange couples the ferromagnetic free layer ( 27 ) to the ferromagnetic biasing layer ( 25 ) by ferromagnetic coupling to produce parallel magnetizations ( 11 ) labeled M 2 (biasing layer) and M 1 (free layer). The remainder of the configuration comprises an antiferromagnetically coupled (synthetic) pinned layer ( 30 ), which comprises two ferromagnetic layers (( 32 ) and ( 34 )) antiferromagnetically exchange coupled across a non-magnetic coupling layer ( 36 ) and which is separated from ( 27 ) by a non magnetic spacer layer ( 31 ). Beneath ( 30 ) there is an antiferromagnetic pinning layer ( 40 ), typically a layer of MnPt, which pins the antiferromagnetically coupled pinned layer. The magnetic moments of the antiferromagnetically coupled pinned layers are in the transverse direction (perpendicular to the plane of the figure) and are antiparallel, with the directions of magnetization of the individual layers indicated by circles ( 15 ) (out of the plane) and crosses within circles ( 17 ) (into the plane). Obtaining perpendicularity of the free layer magnetization and pinned layer magnetization complicates the fabrication process of the sensor, since two different antiferromagnetic materials with different blocking temperatures are typically required for ( 40 ) and ( 29 ), eg. IrMn and MnPt in this illustration, as are different annealing schedules so that the magnetization of the pinned layer should not affect the magnetization of the biasing layer. When the physical trackwidth ( 10 ) of this entire configuration is narrow, however, (less than 0.2 microns) the strength of the ferromagnetic coupling (the pinning field) is weak and is typically less than 250 Oe. Note that thicknesses are not given for this figure since the configuration is shown for comparison purposes only.
First Preferred Embodiment
Referring next to FIG. 3 a, there is shown a schematic cross-sectional view of the air bearing surface (ABS) of a synthetic exchange longitudinally biased GMR sensor, before patterning, fabricated in accord with the objects of a first embodiment of the present invention and having the properties and advantages of said embodiment. The device is fabricated in a sequence of three major steps: 1) depositing the sensor layers; 2) annealing and magnetizing the synthetic pinned layer and the synthetic biased free layer; 3) patterning.
1) Deposition Process
First there is deposited a seed layer ( 9 ), which is typically a layer of NiCr deposited to a thickness of between approximately 55 and 65 angstroms with 60 angstroms being preferred. On this seed layer is then deposited a first antiferromagnetic layer ( 40 ) to serve as a pinning layer. Typically this pinning layer is a layer of MnPt deposited to a thickness of between approximately 80 and 150 angstroms with 100 angstroms being preferred. On the pinning layer, and pinned by it, there is then formed a synthetic antiferromagnetic pinned layer ( 30 ), which is an antiferromagnetically coupled trilayer comprising a first ferromagnetic layer ( 32 ), a first non-magnetic antiferromagnetically coupling layer ( 36 ) formed on ( 32 ) and a second ferromagnetic layer ( 34 ) formed on the coupling layer. The ferromagnetic layers are typically layers of CoFe, with the first layer having a thickness of between approximately 12 and 20 angstroms with 15 angstroms being preferred and the second layer having a thickness of between approximately 15 and 25 angstroms with 20 angstroms being preferred. The coupling layer, which is typically a layer of Ru, is formed to a thickness of between approximately 7 and 9 angstroms with 7.5 angstroms being preferred. On the synthetic pinned layer is then formed a non-magnetic spacer layer ( 31 ), which separates the pinned and free layers. This spacer layer is typically a layer of Cu, which is formed to a thickness of between approximately 13 and 25 angstroms with 18 angstroms being preferred. The free layer ( 27 ), which is a ferromagnetic bilayer of CoFe ( 22 ) and NiFe ( 23 ), is then formed on the spacer layer, wherein the CoFe layer has a thickness of between approximately 5 and 15 with 10 angstroms being preferred and the NiFe layer has a thickness of between approximately 15 and 30 angstroms with 20 angstroms being preferred. The free layer is then antiferromagnetically exchange coupled across a non-magnetic coupling layer ( 28 ) to a ferromagnetic biasing layer ( 25 ), forming, thereby, the synthetic exchange biased configuration ( 26 ). The coupling layer in this case is a layer of Ru of thickness between approximately 7 and 9 angstroms with 7.5 angstroms being preferred and the biasing layer is a layer of CoFe of thickness between approximately 10 and 25 angstroms with 15 angstroms being preferred. The synthetic exchange biased configuration ( 26 ) is then pinned by an antiferromagnetic layer of IrMn ( 29 ) of thickness between approximately 35 and 55 angstroms with 40 angstroms being preferred. A conducting lead layer ( 20 ) is deposited over the IrMn layer in a lead overlay (LOL) configuration. The lead layer is typically a Ta/Au bilayer of thickness between approximately 100 and 500 angstroms.
2) Annealing Process
The GMR sensor configuration thus formed is then given a first pinned layer annealing to fix the magnetizations of both synthetic pinned layers ( 30 ) & ( 26 ). The anneal consists of a 5 hour 280° C. anneal in an external transversely directed magnetic field of approximately 10 kOe (kilo-oersteds) to set both pinned layers in the transverse direction (perpendicular to the air-bearing surface). The resulting magnetization vectors are shown only for the first pinned layer ( 30 ) as a circle ( 15 ), representing a direction out of the plane, and a circle with an interior cross ( 17 ), representing a direction into the plane. Following this first pinned layer anneal, a second anneal is applied at a lower temperature and lower magnetic field to reset the magnetization of the synthetic exchange biased layer ( 26 ) from the transverse direction into the longitudinal direction. This second anneal is carried out for a time of approximately 30 minutes at an annealing temperature of approximately 250° C., which is higher than the IrMn blocking temperature. The resulting magnetizations are shown as arrows, M 1 ( 12 ) being the magnetization of the free layer and M 2 ( 11 ) that of the biasing layer. Under this anneal, the synthetic pinned layer ( 30 ) retains its transverse magnetization. It is found by experiment that the configuration described above, under the sequence of anneals to which it is subjected as is also described above, has the advantageous properties of a high pinning field that is approximately 755 Oe, as well as a desirable value of free layer magnetostriction.
3) Patterning Process
Referring now to FIG. 3 b, there is shown a schematic diagram illustrating the process by which a physical trackwidth ( 10 ) of approximately 0.1 microns is formed in the sensor of FIG. 3 a by etching the lead and pinning layers to form the patterned exchange structure. Patterning is done by sequentially removing the entire thickness of a lateral portion of the lead layer ( 40 ) (shown in dashed outline ) and the entire thickness of the IrMn pinning layer beneath it ( 42 ) (shown in dashed outline) by use of a reactive ion etch (RIE) or an ion beam etch (IBE). Removal of these two layers exposes a portion of the CoFe biasing layer ( 44 ), said portion then being effectively removed by an oxidation process, which converts it to a non-magnetic CoFeO (shown shaded). In this process, the antiferromagnetically coupling layer ( 28 ) of Ru acts as an oxidation barrier to prevent the oxidation from extending downward to adversely affect the ferromagnetic free layer ( 27 ). The surface of the coupling layer ( 28 ) beneath ( 44 ) is thereby itself oxidized at the termination of the process. Note in the synthetic pinned layer ( 30 ) that small circles ( 15 ) represent magnetizations out of the plane, circles with interior crosses ( 17 ) are into the plane. The symbols M 1 ( 12 ) and M 2 ( 11 ) refer to the antiparallel directions of the magnetizations of the free (M 1 ) and pinning (M 2 ) layers.
Second Preferred Embodiment
Referring next to FIG. 4 a, there is shown a schematic cross-sectional view of the air bearing surface (ABS) of a synthetic exchange transversely biased GMR sensor, before patterning, fabricated in accord with the objects of a second embodiment of the present invention and having the properties and advantages of said embodiment. The device is fabricated in a sequence of three major steps: 1) depositing the sensor layers; 2 ) annealing and magnetizing the synthetic pinned layer and the synthetic biased free layer; 3 ) patterning.
1) Deposition Process
First there is deposited a seed layer ( 9 ), which is typically a layer of NiCr deposited to a thickness of between approximately 50 and 60 angstroms. On this seed layer is then deposited a first antiferromagnetic layer ( 40 ) to serve as a pinning layer. Typically this pinning layer is a layer of MnPt deposited to a thickness of between approximately 100 and 150 angstroms, but other antiferromagnetic materials such as NiMn, PdPtMn, FeMn or IrMn can be used. On the first pinning layer, and to be pinned by it, there is then formed a synthetic antiferromagnetic pinned layer ( 30 ), which is an antiferromagnetically coupled trilayer comprising a first ferromagnetic layer ( 32 ), a first non-magnetic antiferromagnetically coupling layer ( 36 ) formed on ( 32 ) and a second ferromagnetic layer ( 34 ) formed on the coupling layer. The ferromagnetic layers are typically layers of CoFe, with the first ferromagnetic layer having a thickness of between approximately 15 and 20 angstroms with 15 angstroms being preferred and the second ferromagnetic layer having a thickness of between approximately 20 and 25 angstroms with 20 angstroms being preferred. The first coupling layer, which can be a layer of Ru, is formed to a thickness of between approximately 7 and 9 angstroms with 7.5 angstroms being preferred. Alternatively, the first coupling layer can be a layer of Rh, formed to a thickness of between 4 and 6 angstroms with 5 angstroms being preferred. On the synthetic antiferromagnetic pinned layer there is then formed a non-magnetic spacer layer ( 31 ), which separates the pinned and free layers. This spacer layer is typically a layer of Cu, which is formed to a thickness of between approximately 15 and 22 angstroms with 18 angstroms being preferred. The free layer ( 27 ), which is preferably a ferromagnetic bilayer of CoFe ( 22 ) and NiFe ( 23 ), is then formed on the spacer layer, wherein the CoFe layer has a thickness of between approximately 5 and 15 with 10 angstroms being preferred and the NiFe layer has a thickness of between approximately 15 and 30 angstroms with 20 angstroms being preferred. The free layer is then antiferromagnetically exchange coupled across a second non-magnetic coupling layer ( 28 ) to a ferromagnetic biasing layer ( 25 ), forming, thereby, the synthetic exchange biased configuration ( 26 ). If the first non-magnetic coupling layer ( 36 ) is a layer of Ru, then the second non-magnetic coupling layer ( 28 ) is also a layer of Ru of thickness between approximately 7 and 8 angstroms with 7.5 angstroms being preferred. If the first coupling layer is a layer of Rh, then the second coupling layer is also a layer of Rh of a thickness between 4 and 6 angstroms with 5 angstroms being preferred. If the second coupling layer is Ru, the biasing layer ( 25 ) is a layer of CoFe of thickness between approximately 15 and 30 angstroms with 15 angstroms being preferred. If the second coupling layer is Rh, the biasing layer ( 25 ) is a layer of CoFe of thickness between approximately 25 and 30 angstroms with 28 angstroms being preferred. It is to be noted that the thicker biasing layer ( 25 ) formed in conjunction with the Rh coupling layer produces a greater pinning field in the sensor.
The synthetic exchange biased configuration ( 26 ) is then pinned by a second pinning layer, which is an antiferromagnetic layer of MnPt ( 25 ) of thickness between approximately 80 and 100 angstroms with 100 angstroms being preferred (note, if any of the other antiferromagnetic materials mentioned above have been used to form the first pinning layer, that same material can also be used here to form the second pinning layer). A conducting lead layer ( 20 ) is deposited over the MnPt layer ( 25 ) in a lead overlay (LOL) configuration. The lead layer is typically a Ta/Au/Ta trilayer of thickness between approximately 200 and 400 angstroms.
2) Annealing Process
The GMR sensor configuration thus formed is then given a pinned layer annealing to fix the magnetization of both synthetic pinned layers ( 26 ) & ( 30 ), which are, respectively, the antiferromagnetic pinned layer and the synthetic exchange biased configuration. The anneal consists of a 5 hour 280° C. anneal in an external magnetic field of approximately 10 kOe (kilo-oersteds) to set both pinned layers in the transverse direction (perpendicular to the air-bearing surface). The resulting magnetization vectors are shown as circles ( 53 & 57 ) representing magnetizations out of the plane, and circles with interior crosses ( 51 & 55 ) representing magnetizations into the plane. M 1 and M 2 are the labels representing the magnetizations of the free and biasing layers respectively. It is found by experiment that the configuration described above, under the anneal to which it is subjected as is also described above, has the advantageous properties of a high pinning field that is more than 1000 Oe, as well as an effective trackwidth of less than 0.15 microns subsequent to the patterning that will now be described. A significant advantage of the transverse directions of both the free and pinned layers is that there is a plateau of very little relative rotation of their magnetizations under small external magnetic fields. This plateau is particularly important in the region of the free layer directly beneath the biasing layer in that it leads to extremely small signals being produced by this portion of the free layer. Since unwanted side reading is a direct result of signals emanating from the extreme lateral portions of the free layer, this diminution of signals from that portion is directly responsible for the narrow effective trackwidth. Another important advantage of the transverse directions of both the free and pinned layers is that it is unnecessary to rotate the free layer magnetization with a second anneal after fixing the magnetization of the pinned layer. This allows the use of antiferromagnetic pinning layers of the same high blocking temperature material to be used to pin both the synthetic pinned layer and the synthetic exchange biased free layer. In turn, this allows high external fields to be used to fix the pinning field, which increases the efficacy of the biasing layer and reduces the effective trackwidth of the sensor. It has also been demonstrated that the high pinning fields thus obtained (exceeding 1000 Oe) eliminate the need for current shunting of the sensor current, which permits the use of thinner conducting lead layers and provides a more advantageous topology.
3) Patterning Process
Referring now to FIG. 4 b, there is shown a schematic diagram illustrating the process by which a physical trackwidth ( 10 ) of approximately 0.1 microns is formed in the sensor of FIG. 4 a by patterning the lead and pinning layers to form the patterned exchange structure. Patterning is done by sequentially removing the entire thickness of a lateral portion of the lead layer (( 40 ) shown in dashed outline) and the entire thickness of the MnPt pinning layer beneath it (( 42 ) shown in dashed outline) by use of a reactive ion etch (RIE) or an ion beam etch (IBE). Removal of these two layers exposes the CoFe biasing layer ( 42 ), the portion of which is exposed (( 44 ) shown shaded) being then effectively removed by an oxidation process, which converts it to non-magnetic CoFeO. In this process, the antiferromagnetically coupling layer ( 28 ) of Ru (or Rh) acts as an oxidation barrier to prevent the oxidation from extending downward to the ferromagnetic free layer ( 27 ) and adversely affecting it. The exposed surface of the coupling layer ( 28 ) is thereby itself oxidized at the termination of the process.
Third Preferred Embodiment
Referring next to FIG. 5 a, there is shown a schematic cross-sectional view of the air bearing surface (ABS) of a partially fabricated synthetic exchange transversely biased GMR sensor, before the antiparallel magnetization of its biasing layer and before deposition of a conducting lead layer and final patterning, fabricated in accord with the objects of a third embodiment of the present invention and having the properties and advantages of said embodiment. In this embodiment the transverse magnetizations of the pinning layer and free layer are antiparallel to each other at the opposite ends of the sensor where they are beneath the conducting lead layers. This configuration has been shown to have two advantages: 1) prevention of the bias point shift at the center active region of the free layer and 2) minimization of side reading at both sides of the sensor element.
The device is fabricated in a sequence of four steps: 1) depositing the sensor layers up to and including the exchange biasing layer (shown in FIG. 5 a ); 2) separately magnetizing both lateral ends of the exchange biasing layer in opposite transverse directions using a two-step patterning and annealing sequence (shown in FIGS. 5 b and 5 c ); 3) depositing conducting lead layers (shown in FIG. 5 d ); 4) patterning ( FIG. 5 d ).
1) Deposition Process
Referring to FIG. 5 a and looking vertically upward, there is first seen deposited a seed layer ( 9 ), which is typically a layer of NiCr deposited to a thickness of between approximately 50 and 60 angstroms. On this seed layer is then deposited a first antiferromagnetic layer ( 40 ) to serve as a pinning layer. Typically this pinning layer is a layer of MnPt deposited to a thickness of between approximately 100 and 150 angstroms, but other antiferromagnetic materials such as NiMn, PdPtMn, FeMn or IrMn can be used. On the first pinning layer there is then formed a synthetic antiferromagnetic pinned layer ( 30 ), which is an antiferromagnetically coupled trilayer comprising a first ferromagnetic layer ( 32 ), a first non-magnetic antiferromagnetically coupling layer ( 36 ) formed on ( 32 ) and a second ferromagnetic layer ( 34 ) formed on the coupling layer. The ferromagnetic layers are typically layers of CoFe, with the first ferromagnetic layer having a thickness of between approximately 15 and 20 angstroms with 15 angstroms being preferred and the second ferromagnetic layer having a thickness of between approximately 20 and 25 angstroms with 20 angstroms being preferred. The first non-magnetic antiferromagnetically coupling layer, which can be a layer of Ru, is formed to a thickness of between approximately 7 and 9 angstroms with 7.5 angstroms being preferred. Alternatively, the first coupling layer can be a layer of Rh, formed to a thickness of between 4 and 6 angstroms with 5 angstroms being preferred. In either case, the layer is formed of a material and to a thickness that will cause the two ferromagnetic layers to align their magnetizations in an antiparallel direction upon annealing. On the synthetic pinned layer there is then formed a non-magnetic spacer layer ( 31 ), which separates the pinned and free layers. This spacer layer is typically a layer of Cu, which is formed to a thickness of between approximately 15 and 22 angstroms with 18 angstroms being preferred. The free layer ( 27 ), which in this preferred embodiment is a ferromagnetic bilayer of CoFe ( 22 ) and NiFe ( 23 ), is then formed on the spacer layer, wherein the CoFe layer has a thickness of between approximately 5 and 15 with 10 angstroms being preferred and the NiFe layer has a thickness of between approximately 15 and 30 angstroms with 20 angstroms being preferred. The free layer is then antiferromagnetically exchange coupled across a second non-magnetic coupling layer ( 28 ) to a ferromagnetic biasing layer ( 25 ), forming, thereby, the synthetic antiferromagnetic exchange biased configuration ( 26 ). If the first non-magnetic coupling layer ( 36 ) is a layer of Ru, then the second non-magnetic coupling layer ( 28 ) is also a layer of Ru of thickness between approximately 7 and 8 angstroms with 7.5 angstroms being preferred. If the first coupling layer is a layer of Rh, then the second coupling layer is also a layer of Rh of a thickness between 4 and 6 angstroms with 5 angstroms being preferred. If the second coupling layer is Ru, the biasing layer ( 25 ) is a layer of CoFe of thickness between approximately 15 and 30 angstroms with 15 angstroms being preferred. If the second coupling layer is Rh, the biasing layer ( 25 ) is a layer of CoFe of thickness between approximately 25 and 30 angstroms with 28 angstroms being preferred. It is to be noted that the thicker biasing layer ( 25 ) formed in conjunction with the Rh coupling layer produces a greater pinning field in the sensor. At this point in the fabrication process the magnetization of the pinned layer can be set by an anneal in the same manner as in the previous embodiments. A 5 hour anneal in a 10 kOe magnetic field at a temperature of 280° C. is preferred.
Referring now to FIG. 5 b, there is shown an upper portion of the structure of FIG. 5 a wherein a lateral portion ( 60 ) of the ferromagnetic biasing layer ( 25 ) has been covered by a layer of etch resistant material ( 62 ) (such as photoresist), leaving the remaining portion (shown shaded) of the biasing layer uncovered ( 64 ). This uncovered portion is then cleaned by a sputter etch process.
Referring next to FIG. 5 c, there is shown the cleaned portion ( 64 ) refilled with the same ferromagnetic material of the biasing layer and covered by an additional layer of antiferromagnetic material ( 66 ), such as a layer of IrMn deposited to a thickness 0 f between approximately 35 and 55 angstroms with 40 angstroms being preferred, to act as a pinning layer. During this deposition process, the fabrication thus produced is annealed in a first transverse magnetic field in a first transverse direction to fix the direction of the magnetizations in the antiferromagnetic coupling between the portion of the biasing layer ( 64 ), whose magnetization is shown as a circle ( 68 ), and the corresponding portion of the free layer ( 27 ) beneath it, whose antiparallel magnetization is shown as a circle with a cross ( 69 ). The first anneal is for between approximately 30 and 60 minutes but where approximately 30 minutes is preferred, at a temperature of between approximately 250° C. and 280° C., but where 250° C. is preferred and with a magnetic field of between approximately 250 and 500 Oe but where 250 Oe is preferred. The antiferromagnetic layer ( 66 ) pins the biasing layer in this process.
Referring next to FIG. 5 d, there is shown the fabrication of FIG. 5 c, wherein the surface of the opposite lateral portion ( 72 ) of the biasing layer is now exposed, while the remainder of the layer, which has already been magnetized, is covered by a resistant layer ( 74 ), such as a layer of photoresist. In a similar fashion to that described in FIG. 5 c, the portion ( 72 ) is cleaned and covered with additional biasing material and, over it, a layer of antiferromagnetic pinning material ( 75 ) such as IrMn is formed in a manner identical to that described in FIG. 5 c . During the deposition process a second external magnetic field in the opposite direction to that used in the process of FIG. 5 c is applied and the biasing layer portion ( 72 ) is thereby magnetized in the direction of that magnetic field (circle with a cross ( 81 )) and the free layer beneath it ( 27 ) is oppositely magnetized (circle ( 83 )). The second anneal, like the first, is for between approximately 30 and 60 minutes but where approximately 30 minutes is preferred, at a temperature of between approximately 250° C. and 280° C., but where 250° C. is preferred and with a magnetic field of between approximately 250 and 500 Oe but where 250 Oe is preferred. The deposited antiferromagnetic layer ( 75 ) serves to pin the biasing layer by this process.
Referring now to FIG. 5 e, there is shown the fabrication of FIG. 5 d wherein a central portion ( 85 ) of the twice magnetized biasing layer is removed by an ion beam or chemical etching process to form a trackwidth of desired dimension. A conducting lead layer ( 90 ) has been formed over the two biasing layers. The lead layer is typically a Ta/Au/Ta trilayer of thickness between approximately 200 and 400 angstroms.
As is understood by a person skilled in the art, the preferred embodiments of the present invention are illustrative of the present invention rather than limiting of the present invention. Revisions and modifications may be made to methods, materials, structures and dimensions employed in fabricating a synthetic, patterned, longitudinally or transversely exchange biased GMR sensor with narrow effective trackwidth, while still providing a method for fabricating such a synthetic, patterned, longitudinally or transversely exchange biased GMR sensor with narrow effective trackwidth, in accord with the spirit and scope of the present invention as defined by the appended claims. | Patterned, longitudinally and transversely antiferromagnetically exchange biased GMR sensors are provided which have narrow effective trackwidths and reduced side reading. The exchange biasing significantly reduces signals produced by the portion of the ferromagnetic free layer that is underneath the conducting leads while still providing a strong pinning field to maintain sensor stability. In the case of the transversely biased sensor, the magnetization of the free and biasing layers in the same direction as the pinned layer simplifies the fabrication process and permits the formation of thinner leads by eliminating the necessity for current shunting. | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates to a dielectric ceramic material and, more particularly, to a dielectric ceramic material exhibiting improved characteristics including a small dielectric loss and a small absolute value of temperature coefficient of resonance frequency.
BACKGROUND OF THE INVENTION
[0002] Conventionally, a variety of compositions of dielectric ceramic materials have been investigated in order to adapt the ceramic materials to use in a high-frequency region such as the microwave region or the milliwave region, where dielectric characteristics such as a large relative dielectric constant, a small dielectric loss, and a small absolute value of temperature coefficient of resonance frequency are required. In relation to such dielectric ceramic materials, Japanese Patent Publication (kokoku) Nos. 2-53884 and 4-321 and other publications disclose dielectric ceramic materials having a BaNbO 3 component. The Ba(Zn, Nb) dielectric materials disclosed in the above publications exhibit excellent characteristics; i.e., a high unloaded quality coefficient and a small temperature coefficient of resonance frequency.
[0003] However, the aforementioned Ba(Zn, Nb) dielectric materials do not necessarily exhibit a satisfactory percent maintenance of unloaded quality coefficient as expressed by percentage of unloaded quality coefficient measured at high temperature (approximately 125° C.) with respect to that measured at room temperature (approximately 25° C.). Therefore, when these dielectric ceramic materials are used in dielectric resonators and other apparatus, dielectric loss at high frequency problematically increases. In order to overcome this problem, researchers have pursued development of dielectric ceramic materials which exhibit improved dielectric characteristics and a small temperature dependency on resonance frequency and which maintain a high percent maintenance of Q value as expressed as a percentage of Q value measured at high temperature with respect to that measured at room temperature.
SUMMARY OF THE INVENTION
[0004] The present invention is basically concerned with overcoming the aforementioned drawbacks of the prior art. Thus, an object of the present invention is to provide a dielectric ceramic material which can attain a large unloaded quality coefficient and a small absolute value of temperature coefficient of resonance frequency as compared with conventional dielectric ceramic materials containing a BaNbO 3 component and which allows selection of dielectric characteristics over a wide range.
[0005] Another object of the invention is to provide a dielectric ceramic material which enables provision of improved dielectric characteristics through firing at a lower temperature.
[0006] Still another object of the invention is to provide a dielectric ceramic material which can maintain a high percent maintenance Q value as expressed as a percentage of Q value measured at high temperature with respect to that measured at room temperature.
[0007] The present invention concerns a dielectric ceramic material comprising Ba, Nb, and Ta; at least one of Zn and Co; and at least one species selected from the group consisting of K, Na, and Li, the ceramic material being represented by the compositional formula: (100-a)[Ba u {(Zn v Co 1-v ) w Nb x }O 67 1 ]-a[M y Ta z O δ2 ] where M represents at least one species selected from the group consisting of K, Na, and Li, and the following relations are satisfied simultaneously: 0.5≦a≦25; 0.98≦u≦1.03; 0≦v ≦1; 0.274≦w <0.374; 0.646≦x≦0.696; 0.5≦y≦2.5; and 0.8≦z≦1.2.
[0008] The present invention also concerns a dielectric ceramic material represented by the compositional formula, (100-a)[Ba u {(Zn v Co 1-v ) w Nb x )O 67 1 ]-a[M y Ta z O δ2 ], where M represents at least one species selected from the group consisting of K, Na, and L. The ceramic material is produced by mixing raw material powders such that proportions by mol of component metals simultaneously satisfy the relations: 0.5≦a≦25; 0.98≦u≦1.03; 0≦v≦1; 0.274≦w≦0.374; 0.646≦x≦0.696; 0.5 ≦y≦2.5; and 0.8≦z≦1.2. The resultant mixture powder is molded to thereby yield a compact and the compact is fired.
[0009] The present invention also concerns a dielectric ceramic material comprising Ba, Nb, and Ta; at least one of Zn and Co; at least one species selected from the group consisting of K, Na, and Li; and Mn or W, where Mn and W are contained in amounts of 0.02-3 mass % as reduced to MnO 2 and 0.02-4.5 mass % as reduced to WO 3 , respectively, on the basis of 100 parts by mass of the composition: (100-a)[Ba u {(Zn v Co 1-v ) w Nb x }O δ1 ]-a[M y T a O δ2 ] where M represents at least one species selected from the group consisting of K, Na, and Li, and the relations: 0.5≦a≦25; 0.98≦u≦1.03; 0≦v≦1; 0.274≦w≦0.374; 0.646≦x≦0.696; 0.5≦y≦2.5; and 0.8≦z≦1.2 are satisfied simultaneously.
[0010] The present invention also concerns a method for manufacturing a dielectric ceramic material which includes mixing raw material powders which will comprise the dielectric ceramic material represented by the compositional formula: (100-a)[Ba u {(Zn v Co 1-v ) w Nb x }O δ1 -a[M y Ta z , O δ2 ], where M represents at least one species selected from the group consisting of K, Na, and Li, such that proportions by mol of component metals simultaneously satisfy the relations: 0.5≦a≦25; 0.98≦u ≦1.03; 0≦v≦1; 0.274≦w≦0.374; 0.646≦x≦0.696; 0.5≦y≦2.5; and 0.8≦z≦1.2. The resultant mixture powder is molded to thereby yield a compact and the compact is fired.
[0011] Further features and advantages of the present invention will be set forth in, or apparent from, the detailed description of preferred embodiments thereof which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] [0012]FIG. 1 is a graph showing correlation between a and εr;
[0013] [0013]FIG. 2 is a graph showing correlation between a and Q 0 ;
[0014] [0014]FIG. 3 is a graph showing correlation between a and Q 0 of 0 ;
[0015] [0015]FIG. 4 is a graph showing correlation between a and τf;
[0016] [0016]FIG. 5 is a graph showing correlation between firing temperature and εr;
[0017] [0017]FIG. 6 is a graph showing relationship between firing temperature and Q 0 ;
[0018] [0018]FIG. 7 is a graph showing correlation between firing temperature and Q 0 f 0 ;
[0019] [0019]FIG. 8 is a graph showing correlation between firing temperature and τf;
[0020] [0020]FIG. 9 is a graph showing correlation between v and εr;
[0021] [0021]FIG. 10 is a graph showing correlation between v and Q 0 ;
[0022] [0022]FIG. 11 is a graph showing correlation between v and τf;
[0023] [0023]FIG. 12 is a chart of X-ray diffraction measurement of dielectric ceramic materials with increasing a;
[0024] [0024]FIG. 13 is an enlarged portion of FIG. 12; and
[0025] [0025]FIG. 14 is a graph showing correlation between a values and d values obtained through X-ray diffractometry of the dielectric ceramic materials according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] The incorporation of M and Ta into a ceramic material allows one to obtain a dielectric ceramic material exhibiting a large unloaded quality coefficient (which hereinafter may be referred to simply as “Q 0 ”) as compared with a dielectric ceramic material containing no M or Ta. In such a case, even though the amounts of M or Ta added are small, a remarkably large Q 0 of the dielectric ceramic material containing M and Ta can be provided as compared with a dielectric ceramic material containing no M or Ta (see FIGS. 2 and 3). Moreover, the resultant ceramic material shows quite unexpected behavior; the Q 0 shows its peak (maximum) in the vicinity of a=2.5. This effect is significantly remarkable when M is K or Na, and most remarkable when M is K.
[0027] Through incorporation of M and Ta into the ceramic material, a dielectric ceramic material exhibiting a small absolute value of temperature coefficient of resonance frequency (hereinafter may be referred to simply as “τf”) can be produced. In such a case, even though the amounts of M and Ta added are small, a remarkably small absolute value of τf of the dielectric ceramic material containing M and Ta can be obtained as compared with a dielectric ceramic material containing no M or Ta (see FIG. 4). Moreover, the resultant ceramic material shows quite unexpected behavior; the τf shows its peak (minimum) approximately at a=5. This effect is particularly remarkable when M is K or Li.
[0028] Through incorporation of M and Ta into the ceramic material, the firing temperature during production of the dielectric ceramic material of the present invention can also be lowered. Particularly when M is K, a dielectric ceramic material exhibiting well-balanced dielectric characteristics; i.e., a large relative dielectric constant (hereinafter may be referred to simply as “εr”), a large Q 0 , and a small absolute value of τf can be produced through firing at a low firing temperature (see FIGS. 5 to 8 ).
[0029] The value of “a,” representing (M +Ta) content, satisfies the relation 0.5≦a≦25. When a is less than 0.5, the aforementioned effects commensurate with incorporation of M and Ta may be difficult to attain, whereas when a is in excess of 25, the ceramic material compact cannot maintain its shape during firing, possibly resulting in difficulty in production of dielectric ceramics. Although no particular limitation is imposed on the value of a so long as a falls within the above range, the range is preferably 1≦a≦20, more preferably 1≦a≦10, most preferably 2≦a≦8, from the viewpoint of the aforementioned effects.
[0030] The value of “y” satisfies the relation 0.5≦y≦2.5(preferably 1.0≦y≦2.0). When y is less than 0.5, sufficient sintering tends to be difficult. When y is less than 0.5 or in excess of 2.5, the product of unloaded quality coefficient and resonance frequency (hereinafter may be referred to simply as “Q 0 ·f 0 ”) may be problematically insufficient.
[0031] The value of “z” satisfies the relation 0.8≦z≦1.2. When z falls within 0.9≦z≦1.1, Q 0 ·f 0 attains a particularly large value, which is preferable. In contrast, when z is less than 0.8 or in excess of 1.2, a sufficiently large Q 0 ·f 0 value may fail to be attained, which is disadvantageous.
[0032] The dielectric ceramic material of the composition contains at least one of Zn and Co. The absolute value of Q 0 and that of τf can be controlled over a wide range through modification of the Zn content or the Co content. Particularly, increase in Zn content remarkably elevates Q 0 (see FIG. 10). However, Q 0 exhibits its peak value at a certain Zn content (or Co content) when the Zn content is varied. This unexpected feature is different from the behavior of εr (absolute value) and that of τf (see FIGS. 9 and 11). In addition to elevating Q 0 , increase in Zn content can elevate εr (see FIG. 9) and reduce the absolute value of τf (see FIG. 11).
[0033] The value of “v,” representing Zn content, can be modified within a range of 0≦v≦1. Although no particular limitation is imposed on v, a preferred range is 0.3≦v≦1 in that all dielectric characteristics can be enhanced. A range of 0.4≦v≦0.8 is more preferred, in that Q 0 can be maintained at a high level. A range of 0.4≦v≦0.75 is particularly preferred, in that well-balanced dielectric properties; i.e., a large Q 0 and a small absolute value of τf, can be attained. Needless to say, the aforementioned “1-v,” representing Co content, can also be modified within a range of 0≦1-v≦1.
[0034] The value of “u” satisfies the relation 0.98≦u≦1.03, preferably 0.99≦u≦1.02. When u is less than 0.98 or in excess of 1.03, a sufficiently large Q 0 ·f 0 value may fail to be attained, which is disadvantageous. When u is in excess of 1.03, satisfactory sintering tends to be difficult to attain.
[0035] The value of “w” satisfies the relation 0.274≦w≦0.374, preferably 0.294≦w≦0.354. When w is less than 0.274 or in excess of 0.374, a sufficiently large Q 0 ·f 0 value may fail to be attained, which is disadvantageous.
[0036] The value of “x” satisfies the relation 0.646≦x≦0.696, preferably 0.656≦w≦0.686. When x is less than 0.646 or in excess of 0.696, a sufficiently large Q 0 ·f 0 value may fail to be attained, which is disadvantageous.
[0037] The value of “δ1∓ or “δ2” generally equals to an equivalent value with respect to the metal species contained. However, the value is not particularly fixed to the equivalent value so long as the desired dielectric characteristics are not impaired. For example, δ1 falls within a range of 2.9≦δ1≦3.1, and δ2 falls within a range of 2.5≦δ2≦4.
[0038] The compositional formula of the dielectric ceramic material is represented by two terms; i.e., [Ba u {(Zn v Co 1-v ) w Nb x }O δ1 ](hereinafter referred to simply as “BZCN component”) and [M y Ta z O δ2 ] (hereinafter referred to simply as “MT component”). However, in the dielectric ceramic material, the BZCN component and the MT component form a solid solution having a single composition. Formation of the solid solution is confirmed by failure to observe an intrinsic diffraction peak (31.69° ) attributed to the MT component in an X-ray diffraction chart (see FIG. 13); diffraction peaks of a dielectric ceramic material containing the MT component shifting on the higher angle side as compared with diffraction peaks of a BZCN dielectric ceramic material (see FIG. 13); and observation of approximately proportional correlation between the MT component content (a) and d values (see FIG. 14).
[0039] Therefore, according to the present invention, there can be obtained a large Q 0 and a small absolute value of τf, which have not been satisfactorily attained by a dielectric ceramic material formed solely of a BZCN component, and well-balanced dielectric characteristics including these two properties can be provided.
[0040] In addition to containing these components, the dielectric ceramic material of the present composition may further contain Mn or W. The Mn content or W content is such that, with respect to 100 parts by mass of the following composition: (100-a)[Ba u {(Zn v Co 1-v ) w Nb x }O δ1 ]-a[M y T a Zn z O δ2 ], (where M represents at least one species selected from the group consisting of Li, Na, and K, and the following relations are satisfied simultaneously: 0.5≦a≦25; 0.98≦u≦1.03; 0≦v≦1; 0.274≦w≦0.374; 0.646≦x≦0.696; 0.5≦y≦2.5; and 0.8≦z≦1.2), Mn is present in an amount of 0.02-3 mass % as reduced to MnO 2 , preferably 0.02-2.5 mass %, more preferably 0.02-2 mass %, particularly preferably 0.02-1.5 mass %, most preferably 0.05-1.5 mass %, or W is present in an amount of 0.02-4.5 mass % as reduced to WO 3 , preferably 0.02-4 mass %, more preferably 0.02-3.5 mass %, particularly preferably 0.02-3 mass %, most preferably 0.03-2 mass %. Controlling of the aforementioned Mn content or W content (oxide-based) to 0.02 mass % or higher is preferred, since deterioration of percent maintenance of Q value at high temperature can be prevented, and a higher Q value can be maintained. Controlling of the aforementioned Mn content (oxide-based) to 3 mass % or less or the W content (oxide-based) to 4.5 mass % or lower is preferred, since deterioration of percent maintenance of Q value at room temperature and high temperature can be prevented, the absolute value of τf can be reduced, and more excellent dielectric characteristics can be maintained.
[0041] The aforementioned Mn or W is incorporated typically in oxide form such as MnO 2 or WO 3 and resides in the dielectric ceramic material. However, the form is not limited to oxide, and other forms such as salts, halides, and alkoxides may be employed so long as Mn or W can be incorporated into the dielectric ceramic material.
[0042] According to the present invention, when a preferred compositional range and preferred firing temperature are employed, the following characteristics can be attained: εr of 32-37 (preferably 32-36, more preferably 33-35); Q 0 as measured in TE 011 , mode of 7,000-23,000 (preferably 9,000-22,000, more preferably 10,000-21,000); Q 0 ·f 0 as measured in TE 01δ mode of 7,000-63,000 GHz (preferably 10,000-60,000 GHz, more preferably 20,000-60,000 GHz); and temperature coefficient of resonance frequency (τf) of −12 to 34 ppm/° C. (preferably −5 to 32 ppm/° C., more preferably −2 to 15 ppm/° C.).
[0043] When M is K and a is 1-10, the following characteristics can be attained: εr of 32-37 (preferably 32-36, more preferably 33-35); Q 0 as measured in TE 011 mode of 7,000-23,000 (preferably 9,000-22,000, more preferably 10,000-21,000); Q 0 ·f 0 as measured in TE 01δ mode of 7,000-63,000 GHz (preferably 10,000-60,000 GHz, more preferably 20,000-60,000 GHz); and temperature coefficient of resonance frequency (τf) of −12 to 34 ppm/° C. (preferably −5 to 32 ppm/° C., more preferably −2 to 15 ppm/° C.).
[0044] When M is K and a is 2-8, the following characteristics can be attained: εr of 32-37 (preferably 32-36, more preferably 33-35); Q 0 as measured in TE 011 mode of 10,000-23,000 (preferably 11,000-22,000, more preferably 12,000-21,000); Q 0 ·f 0 as measured in TE 01δ , mode of 20,000-63,000 GHz (preferably 30,000-60,000 GHz, more preferably 35,000-60,000 GHz); and temperature coefficient of resonance frequency (τf) of −12 to 34 ppm/° C. (preferably −5 to 32 ppm/° C., more preferably −2 to 15 ppm/° C).
[0045] When M is K, a is 2-8, and v is 0.2-0.8, the following characteristics can be attained: εr of 32-37 (preferably 32-36, more preferably 33-35); Q 0 as measured in TE 011 mode of 10,000-23,000 (preferably 11,000-22,000, more preferably 12,000-21,000); Q 0 ·f 0 as measured in TE 01δ mode of 20,000-63,000 GHz (preferably 30,000-60,000 GHz, more preferably 35,000-60,000 GHz); and temperature coefficient of resonance frequency (τf) of −12 to 34 ppm/° C. (preferably −5 to 32 ppm/° C., more preferably −2 to 15 ppm/° C.).
[0046] When the dielectric ceramic material further contains Mn or W, there can be attained a percent maintenance of Q value as expressed by percentage of Q value measured at 125° C. with respect to that measured at 25° C. of 70% or higher, preferably 72% or higher, more preferably 74% or higher, particularly preferably 75% or higher. The percent maintenance (%) is calculated on the basis of the following equation:
[0047] Percent maintenance (%)=(A/B)×100 where A represents Q 0 ·f 0 as measured at 125° C. in TE 01δ mode and B represents Q 0 ·f 0 as measured at 25° C. in TE 01δ mode. The aforementioned remarkably excellent dielectric characteristics can be provided by a dielectric ceramic material which has been produced through firing at 1,375-1,600° C., preferably 1,425-1,575° C.
[0048] The dielectric characteristics (δr, Q 0 , and τf) were measured in the below-described TE 011 mode. The aforementioned Q 0 ·f 0 was measured in the below-described TE 01δ mode. The reason for employing Q 0 ·f 0 is that Q·f 0 cancels effect of inevitable variation (per measurement) of resonance frequency during measurement of dielectric characteristics. Through employment of Q 0 ·f 0 , dielectric loss can be evaluated more accurately.
[0049] To provide further understanding of the present invention, the following examples are included, it being understood that these examples are only illustrative of the present invention and do not limit its scope in any way.
EXAMPLE 1
Production of Sintered Compacts
[0050] Barium carbonate powder, zirconium oxide powder, cobalt oxide (CoO) powder, niobium oxide (Nb 2 O 5 ) powder, tantalum oxide (Ta 2 O 5 ) powder, and potassium carbonate powder, all being commercial products and having a purity of 99.9% or higher, were weighed in predetermined amounts in accordance with compositional formulas corresponding to the experiments shown in Tables 1 and 2, where A to J appearing in the column of “Experiment No.” represent types of compositions, and 1 to 6 denote the corresponding firing temperatures. Each resultant mixture was dry-mixed for 20-30 minutes by means of a mixer and subjected to primary pulverization by means of a vibration mill. Primary pulverization was performed for four hours by use of alumina balls serving as grinding balls.
[0051] The resultant powder was calcined in air at 1,100-1,300° C. for two hours, to thereby yield a calcined powder. The calcined powder was mixed with an appropriate amount of an organic binder and water, and the resultant mixture was subjected to secondary pulverization for 10-15 hours by means of a trommel pulverizer. The thus-pulverized product was freeze-dried and granulated, and granules having a particle size of 40 mesh to 200 mesh were separated from the granulated product by use of sieves. The thus-separated granules were molded by a press machine into compacts (diameter: 19 mm, height 11 mm). The compacts obtained from the above starting materials were debindered at 500° C. for four hours, and fired in air at a temperature shown in Table 1 or 2 for three hours, to thereby yield sintered compacts having compositions A to J.
[0052] Compacts having composition I (containing no M or Ta, and fired at 1,400° C. or 1,450° C. (1-1 and 1-2)) failed to produce sintered dielectric ceramic material, since the firing temperatures were insufficient for attaining sintering. Compacts having composition D (containing M and Ta at a =20 and fired at 1,500° C. or higher (D-3)) melted during the course of firing, thereby failing to produce a sintered ceramic material, since the firing temperature was excessively high. Similarly, compacts having composition E (containing M and Ta in amounts falling outside the preferred amounts and fired at 1,400° C.) melted during the course of firing, thereby failing to produce sintered ceramic material.
[0053] Although compacts having composition A (containing M and Ta at a =2.5 and fired at 1,400° C. (A-1)) could not be sufficiently sintered, those fired at 1,450-1,600° C. (A-2 to A-6) could produce dielectric ceramic materials. Compacts having composition B (containing M and Ta at a =5 and fired at 1,400° C. (B-1)) could produce dielectric ceramic materials.
[0054] The results indicate that incorporation of M and Ta lowers the firing temperature, and that the firing temperature can be lowered as the amounts of M and Ta increase within a range of a =2.5-20.
TABLE 1 Compositional formula Experiment (100-a)[Ba u [(Zn v Co 1-v ) w Nb x ]O δ1 ]- Firing temp. No. a[M y Ta z O δ2 ] (° C.) *A-1 97.5[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ1 ]- 1,400 A-2 2.5[K 1.5 TaO δ2 ] 1,450 A-3 1,500 A-4 1,525 A-5 1,550 A-6 1,600 B-1 95[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ1 ]- 1,400 B-2 5[K 1.5 TaO δ2 ] 1,450 B-3 1,500 B-5 1,550 C-1 90[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ1 ]- 1,400 10[K 1.5 TaO δ2 ] D-2 80[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ1 ]- 1,450 *D-3 20[K 1.5 TaO δ2 ] 1,500 *E-1 50[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ1 ]- 1,400 50[K 1.5 TaO δ2 ] F-1 97.5[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ1 ]- 1,400 F-2 2.5[Na 1.5 TaO δ2 ] 1,450 F-3 1,500 F-5 1,550 F-6 1,600
[0055] [0055] TABLE 2 Compositional formula Experiment (100-a)[Ba u [(Zn v Co 1-v ) w Nb x ]O δ1 ]- Firing temp. No. a[M y Ta z O δ2 ] (° C.) G-1 97.5[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ1 ]- 1,400 G-3 2.5[Li 1.5 TaO δ2 ] 1,500 G-5 1,550 G-6 1,600 H-1 97.5[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ1 ]- 1,525 2.5[K 1.5 TaO δ2 ] H-2 97.5[Ba 1.01 [(Zn 0.25 Co 0.75 ) 0.324 Nb 0.666 ]O δ1 ]- 2.5[K 1.5 TaO δ2 ] H-3 97.5[Ba 1.01 [(Zn 0.75 Co 0.25 ) 0.324 Nb 0.666 ]O δ1 ]- 2.5[K 1.5 TaO δ2 ] H-4 97.5[Ba 1.01 [Zn 0.324 Nb 0.666 ]O δ1 ]- 2.5[K 1.5 TaO δ2 ] *I-1 95[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ2 ] 1,400 *I-2 1,450 *I-3 1,500 *I-5 1,550 *I-6 1,600 *J-1 50[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O δ1 ]- 1,400 50[K 1.5 TaO δ2 ]
[0056] Each of dielectric ceramic materials produced in [1] (Experiment Nos. 1-3 (a=0), A-4 (a=2.5), B-2 (a=5), C-1 (a=10), and D-2 (a=20)) was pulverized by use of a mortar, and the resultant powder was subjected to X-ray diffractometry (CuKα). FIGS. 12 and 13 are charts showing multiply recorded diffraction patterns. FIG. 12 is a chart showing a scanned angle range of 20-70°, and FIG. 13 is an enlarged portion of FIG. 12 showing diffraction peaks of a main crystal phase confirmed in the vicinity of 31°.
[0057] [0057]FIG. 14 shows correlation between d values of the main crystal diffraction peak obtained through X-ray diffractometry and a values (a: variable in the above compositional formula of the dielectric ceramic material of the present invention).
[0058] [0058]FIGS. 12 and 13 show no diffraction peak at 31.69°, which would be attributed to a phase containing M and Ta when the phase is isolated from a main crystal phase of the BZCN component. In enlarged diffraction peak patterns shown in FIG. 13, diffraction peaks of dielectric ceramic materials containing the MT component shift to the higher angle side as increase in the MT component content, as compared with diffraction peaks of the main crystal phase formed solely of the BZCN component. FIG. 14 shows a proportional relationship between a values and d values. These results indicate that the BZCN component and the MT component form a solid solution in which the two components are mutually dissolved.
[0059] All sintered ceramic compacts that had been produced in Example 1 were polished, to thereby provide columnar ceramic pieces (diameter: 16 mm, height: 8 mm). Each of the polished ceramic pieces was evaluated in terms of εr, Q 0 , and f 0 (temperature range: 25-80° C.) through a parallel-conductor-plates dielectric resonator method in TE 011 mode over 3-5 GHz. The results are shown in Tables 3 and 4. Q 0 and f 0 of the polished ceramic piece were also measured through a dielectric resonator method in TE 01δ mode over 3-4 GHz. Tables 3 and 4 also show values of the product f 0 ·Q 0
TABLE 3 Dielectric characteristics TE 01δ Experi- TE 011 mode ment Composition mode f 0 · Q 0 τf Specific No. type εr Q 0 (GHz) (ppm/° C.) gravity *A-1 KTa-2.5 Unsintered A-2 32.9 19,323 44,330 8.99 6.280 A-3 34.6 19,202 52,580 8.95 6.343 A-4 34.1 20,588 58,742 8.85 6.294 A-5 33.8 19,922 44,629 8.24 6.250 A-6 32.6 8,545.5 8,557 10.53 6.144 B-1 KTa-5.0 23.6 13,698 20,020 11.29 5.432 B-2 34.6 20,237 52,473 7.49 6.327 B-3 33.5 6,936 6,517 12.82 6.095 B-5 32.9 905 703 32.41 5.927 C-1 KTa-10 32.5 18,927 42,109 15.31 5.934 D-2 KTa-20 38.4 10,265 17,168 35.55 6.372 *D-3 Dissolved *E-1 Dissolved F-1 NaTa-2.5 23.5 9,491 6,025 29.97 4.987 F-2 26.6 7,965 2,722 33.62 6.011 F-3 34.8 13,424 23,498 26.18 6.168 F-5 34.0 16,413 33,588 17.24 6.097 F-6 33.0 10,566 13,047 15.39 6.036
[0060] [0060] TABLE 4 Dielectric characteristics TE 01δ Experi- TE 011 mode ment Composition mode f 0 · Q 0 τf Specific No. type εr Q 0 (GHz) (ppm/° C.) gravity G-1 LiTa-2.5 21.2 9,527 4,737 14.44 4.482 G-3 34.1 8,428 11,227 8.53 6.324 G-5 32.2 2,934 2,494 8.32 6.012 G-6 31.6 2,142 1,843 13.15 5.830 H-1 Co-1 30.9 4,297 15,308 −11.5 6.253 H-2 Co-0.75 32.5 10,290 32,084 −1.1 6.287 H-3 Co-0.25 35.6 16,043 66,538 18.5 6.260 H-4 Co-0 36.9 13,027 65,391 31.6 6.173 *I-1 Non-KTa Unsintered *I-2 containing *I-3 29.0 5,120 6,035 20.89 5.515 *I-5 33.1 2,988 2,777 18.67 5.957 *I-6 33.3 6,314 6,419 19.02 5.972 *J-1 KTa-50 Dissolved (sintering impossible)
EXAMPLE 2
[0061] The procedure of Example 1 was repeated, except that manganese oxide (MnO 2 ) powder (purity 95%) and tungsten oxide (WO 3 ) powder (purity 99.8% or higher) were added to the raw material described in Example 1, to thereby yield sintered compact Nos. 1 to 21 having compositions shown in Table 5. Dielectric characteristics of these sintered compact Nos. 1 to 21 were evaluated in a manner similar to that of Example 1. The results are shown in Table 6. In Table 6, the symbol “*” denotes that the Mn content and the W content fall outside the preferred ranges.
TABLE 5 Compositional formula Amount of Experiment (100-a)[Ba u [(Zn v Co 1-v ) w Nb x ]O δ1 ]- Mn, W added No. a[M y Ta z O δ2 ] (mass %) 1 97.5[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.326 Nb 0.666 ]O 3 ]- Mn 0.05 2 2.5[K 1.5 TaO 3 ] Mn 0.10 3 Mn 0.25 4 Mn 0.8 5 Mn 1.3 *6 Mn 0.01 *7 Mn 3.5 8 W 0.05 9 W 0.10 10 W 0.80 11 W 1.5 *12 W 0.01 *13 W 5.0 *14 None 15 95[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O 3 ]- Mn 0.05 5[K 1.5 TaO 3 ] 16 97.5[Ba 1.01 [(Zn 0.5 Co 0.5 ) 0.324 Nb 0.666 ]O 3 ]- Mn 0.05 *17 2.5[Na 1.5 TaO 3 ] None 18 97.5[Ba 1.01 [Co 0.324 Nb 0.666 ]O 3 ]- Mn 0.10 *19 2.5[K 1.5 TaO 3 ] None 20 97.5[Ba 1.01 [Zn 0.324 Nb 0.666 ]O 3 ]- Mn 0.15 *21 2.5[K 1.5 TaO 3 ] Mn 0.01
[0062] [0062] TABLE 6 TE 011 TE 01δ mode Experi- mode f 0 · Q 0 Percent ment f 0 · Q 0 (GHz) maintenance τf No. εr (GHz) 25° C. 125° C. (%) (ppm/° C.) 1 34.1 20,590 59,240 43,720 73.8 8.93 2 34.1 21,000 60,584 46,165 76.2 9.24 3 34.4 20,890 56,221 42,390 75.4 8.72 4 34.5 19,620 52,104 38,870 74.6 9.11 5 35.2 16,600 48,774 38,239 78.4 8.72 *6 34.1 20,600 57,202 37,410 65.4 8.61 *7 34.8 10,500 18,624 14,545 78.1 12.11 8 34.1 20,420 57,733 41,799 72.4 8.64 9 34.2 20,930 61,425 47,973 78.1 8.84 10 34.3 21,150 58,611 45,541 77.7 9.12 11 35.6 18,600 32,614 25,896 79.4 8.72 *12 34.1 20,400 57,912 37,179 64.2 8.84 *13 36.0 9,640 14,272 11,303 79.2 11.21 *14 34.1 20,588 58,742 38,299 65.2 8.85 15 32.5 19,200 43,105 31,984 74.2 15.74 16 34.1 17,200 33,704 25,312 75.1 16.41 *17 34.0 16,413 33,588 21,228 63.2 17.24 18 31.6 5,240 9,440 7,288 77.2 −8.41 *19 30.9 4,297 8,962 6,130 68.4 −11.5 20 36.7 14,620 32,200 25,245 78.4 30.1 *21 36.9 13,027 17,240 11,068 64.2 31.6
[0063] Effects of incorporation of M and Ta can be confirmed from FIGS. 1 to 4 , which correlation between a (i.e., (M plus Ta) content) and Eε, the relationship between a and Q 0 , correlation between a and Q 0 ·f 0 , and correlation between a and τf, respectively. In connection with FIGS. 1 to 4 , among dielectric ceramic material samples having the same composition produced at different firing temperatures, a sample exhibiting most well-balanced dielectric characteristics was selected and the numerical data thereof are plotted.
[0064] It will be apparent to one skilled in the art from FIGS. 1 to 4 , as compared with dielectric ceramic materials containing no M or Ta, that the dielectric ceramic materials of the present composition containing M and Ta exhibit enhanced εr, Q 0 , Q 0 ·f 0 , and τf, regardless of the species of M. In particular, Q 0 , Q 0 ·f 0 , and τf can be remarkably enhanced through incorporation of small amounts (a≦2.5) of M and Ta. Q 0 and Q 0 ·f 0 exhibit their maximum values at a=2.5. Q 0 is as high as 10,000 or more at a =1-20, and Q 0 ·f 0 , is as high as 40,000 GHz or more at a=1-11. τf exhibits its minimum at a=5 and is as low as 8-15[ppm/° C. ] at a=2-10.
[0065] When M is K or Na, the effect of enhancing Q 0 and Q 0 ·f 0 is remarkably great. This effect is particularly enhanced when M is K. Both K and Li exert a great effect of enhancing τf (i.e., lowering the absolute value of τf).
[0066] Effects of the type of M on correlation between firing temperature and dielectric characteristics In order to confirm effects of the type of M on correlation between firing temperature and dielectric characteristics, dielectric ceramic material samples of compositions A, F, and G were investigated in terms of correlation between firing temperature and εr, correlation between firing temperature and Q 0 , correlation between firing temperature and Q 0 ·f 0 , and correlation between firing temperature and τf, and the results are shown in FIGS. 5 to 8 , respectively.
[0067] [0067]FIGS. 5 and 6 show that K is particularly preferred as M, since well-balanced, excellent dielectric characteristics can be attained when the ceramic materials are produced at low firing temperature. Specifically, for a firing temperature of 1,450° C., when M is K, εr, Q 0 , and Q 0 ·f 0 are remarkably increased as compared with the case where M is Na or Li, and the absolute value of εf is remarkably lowered.
[0068] In order to confirm effects of incorporation of Co and Zn, dielectric ceramic material samples of composition G were investigated in terms of correlation between v (Co (or Zn) content) and εr, correlation between v and Q 0 , and correlation between v and τf, and the results are shown in FIGS. 9 to 11 , respectively.
[0069] As shown in FIGS. 9 to 11 , εr and τf increase approximately in proportion to increase in v (i.e., increase in Zn content). Q 0 exhibits unexpected behavior; i.e., increases steeply at V =approximately 0.5, remains approximately constant around v =0.5-0.8, and gradually decreases at V≧0.8. Accordingly, in order to attain well-balanced dielectric characteristics, V is preferably controlled to 0.8 or less, particularly preferably V=0.4-0.8, in that Q 0 is as high as at least 10,000.
[0070] Table 6 shows that sample Nos. 1-5 containing Mn in an amount of 0.02-3 mass % as reduced to MnO 2 exhibit Q 0 ·f 0 at 25° C. of 48,000 GHz or higher, Q 0 ·f 0 at 125° C. of 38,000 GHz or higher, and percent maintenance as high as 74% or more. Similarly, sample Nos. 8-11 containing W in an amount of 0.02-4.5 mass % as reduced to WO 3 show Q 0 ·f 0 at 25° C. of 32,000 GHz or higher, Q 0 ·f 0 at 125° C. of 25,000 GHz or higher, and percent maintenance as high as 72% or more. In addition, sample Nos. 1 to 5 and Nos. 8-11 exhibit τf as small as 9.5 or less. These results indicate that dielectric ceramic materials containing Mn in an amount of 0.02-3 mass % as reduced to MnO 2 or those containing W in an amount of 0.02-4.5 mass % as reduced to WO 3 exhibit more excellent dielectric characteristics and can attain excellent percent maintenance of Q value measured at high temperature with respect to that measured at room temperature.
[0071] Sample Nos. 6, 12, and 14, all having the same composition of the predominant component and containing Mn in an amount of 0.01 mass % as reduced to MnO 2 , W in an amount of 0.01 mass % as reduced to WO 3 , and no Mn or W, respectively, exhibit Q 0 ·f 0 at 25° C. of 57,000 GHz or higher, and Q 0 ·f 0 at 125° C. of 37,000 GHz or higher, but exhibit a low percent maintenance of approximately 64-65%. Sample No. 7 containing Mn in an amount of 3.5 mass % as reduced to MnO 2 and sample No.13 containing W in an amount of 5.0 mass % as reduced to WO 3 , exhibit high percent maintenance of 78.1 % and 79.2%, respectively, but exhibit considerably low Q 0 ·f 0 values; i.e., Q 0 ·f 0 at 25° C. of 19,000 GHz or less, Q 0 ·f 0 at 125° C. of 15,000 GHz or less, and τf of 11 or greater.
[0072] The above tendency is also recognized in pairs of samples; specifically, Nos. 16 and 17, Nos. 18 and 19, and Nos. 20 and 21, each pair of samples having the same composition of the predominant component. Namely, dielectric ceramic material Nos. 16, 18, and 20 containing Mn in an amount of at least 0.02 mass % (as reduced to oxide) exhibit high percent maintenance, whereas dielectric ceramic material Nos. 17, 19, and 21 having an Mn content less than 0.02 mass % exhibit a decreased Q 0 ·f 0 and a decreased percent maintenance.
[0073] As described hereinabove, in order to fully attain the effects of incorporation of M and Ta simultaneously with those of Co and Zn, v preferably falls within a range of 0.4 ≦v≦0.8, and a preferably falls within a range of 1≦a≦11. More preferably, v falls within a range of 0.4≦v≦0.7, and a falls within a range of 2≦a≦8. Particularly preferably, v falls within a range of 0.4≦v≦0.6, and a falls within a range of 2≦a≦6.
[0074] When Mn or W is incorporated, the Mn content is preferably 0.02-3 mass % as reduced to MnO 2 , and the W content is preferably 0.02-4.5 mass % as reduced to WO 3 .
[0075] The present invention is not limited to the aforementioned specific examples, and various modifications may be employed within the scope of the present invention, in accordance with purposes and use. Specifically, other than Ba, Zn, Co, Nb, Ta, K, Na, Li, and O, any elements may be incorporated in certain amounts so long as various dielectric characteristics of the ceramic materials are not impaired in accordance with the disclosure provided herein. No particular limitation is imposed on the additional elements, and examples include Mn, Mg, Fe, W, and B.
[0076] According to the present invention, there can be provided novel dielectric ceramic materials, in particular, dielectric ceramic materials exhibiting a small dielectric loss and a small absolute value of temperature coefficient of resonance frequency. In addition, such dielectric ceramic materials can be produced through firing at low temperature. According to the present invention, high percent maintenance of Q value measured at high temperature with respect to that measured at room temperature can be attained.
[0077] Although the invention has been described above in relation to preferred embodiments thereof, it will be understood by those skilled in the art that variations and modifications can be effected in these preferred embodiments without departing from the scope and spirit of the invention. | A dielectric ceramic material is represented by the following compositional formula, (100-a)[Ba u {(Zn v Co 1-v)w Nb x }O δ1 ]-a[M y Ta 2 O δ2 ], where M represents at least one species selected from K, Na, and Li. In one method, the dielectric material is produced by mixing raw material powders such that proportions by mol of component metals simultaneously satisfy the relations, 0.5≦a≦25; 0.98≦u 23 1.03; 0≦v≦1; 0.274 ≦w≦0.374; 0.646≦x ≦0.696; 0.5≦y≦2.5; and 0.8≦z≦1.2. The method further includes subjecting the resultant mixture to primary pulverization; calcining the resultant powder at 1,100-1,300° C., followed by wet secondary pulverization; drying the resultant paste; granulating; molding the resultant granules to thereby yield a compact; and firing the compact in air advantageously at 1,400-1,600° C. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 11/348,723, filed Feb. 7, 2006.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to additives for animal litter; and more particularly to an additive for cat litter, which releases an odor controlling or odor masking substance when the animal uses a litter-box.
[0004] 2. Description of the Prior Art
[0005] Many commercial litter products contain a scent that either over powers the litter smell or simply has ingredients that mask the litter odor. The litter odor is highly objectionable especially in heated or air-conditioned closed rooms. In these products, the scent producing ingredient is incorporated within the cat litter and the scent from the scented litter is released all the time creating over powering smell in the closed room. This overpowering scent is the reason why many people prefer unscented litter and hope to clean the litter box promptly when the litter box is used by the animal. To aid this cleaning process litter compositions have been developed that clump when the litter box is used for urination thereby enabling the prompt easy cleaning of agglomerated clumps. Yet, the unscented litter progressively accumulates malodor and has to be replaced periodically.
[0006] Many patents disclose methods for control of odor in animal litter. When animal litter is not of a clumping variety, it is difficult to control the odor since the urine excreted is absorbed over a much larger distance. Clumps are created when the composition of the litter swells during the absorption of pet urine, creating a localized rigid clump. Typical additives for litter which provide this swelling action and urine absorption property include gypsum (calcium sulfate hemi-hydrate) which absorbs water, forming CaSO 4 .2H 2 O, swelling Kaolin or montmorillonite clays. Gums of different variety are also used to dissolve and form a bond, creating clumps. Odor control is generally achieved by adding ingredients to the litter that either mask the odor or add compounds that are anti-bacterial, or other compounds that exhibit pleasant smell.
[0007] U.S. Pat. No. 3,675,625 to Miller et al. teaches a litter which is “activated” by heating and then contacted with an odor control agent, such as pine oil, citrus oil, camphor or the like.
[0008] U.S. Pat. No. 4,203,388 to Cortigene et al. teaches the use of a deodorant such as sodium bicarbonate, in amounts of between about 1% and about 10% of the dry weight of the litter. Such large amounts of deodorizer are necessitated since the litter itself is also used as an absorbent for urine, requiring the deodorizer to be homogeneously dispersed throughout the particles of the litter.
[0009] U.S. Pat. No. 4,405,354 to Thomas et al. discloses the use of buffering agents to prevent gaseous ammonia from escaping into the air. However, such buffering agents serve only to prevent the formation of gaseous ammonia; they are ineffective against other unpleasant odors. Further, the amounts of such agents range from about 0.5% to about 25% by weight, since all of the absorbent litter must be treated with the agent to provide sufficient contact with the urine.
[0010] U.S. Pat. No. 4,459,368 to Jaffee, et al. discloses particulate sorbing and deodorizing mixtures containing synthetic and clay sorbents. The composition contains sorbent fuller's earth clay particles and sorbent synthetic particles, e.g. calcium sulfate dihydrate-containing granules, in a weight ratio of about 0.5:9.5 to about 4:6, respectively. This combination of clay minerals and calcium sulfate dihydrate does not provide odor control.
[0011] U.S. Pat. No. 4,517,919 to Benjamin et al. discloses the use of undecylenic acid in amounts from about 1000 to about 10,000 ppm and a bacteriostat in amounts from about 25 to 500 ppm. U.S. Pat. No. 5,094,190 to Ratcliff et al. teaches an odor control animal litter to which a boron-containing liquid material has been applied.
[0012] U.S. Pat. No. 5,097,799 discloses odor control agents selected from the group consisting of guanidine salts, alkali metal fluorides, alkali metal bisulfites, and mixtures thereof. These agents are applied to the litter using an aqueous dispersion to produce an odor control animal litter.
[0013] U.S. Pat. No. 5,183,655 teaches an odor control animal litter that has applied to it an effective amount of pine oil in combination with an effective amount of boric acid.
[0014] U.S. Pat. No. 5,329,880 to Pattengill, et al. discloses clumpable animal litter. This waterproof litter contains a mixture of non-smectitic, hydrophilic shale aggregate with a fraction of coarse material with a size less than about 5 mesh (4000 microns). The mixture has the property of agglomerating into a clump upon contact with urine. The agglomerated clump of shale and urine is removable with a perforated scoop. The shale may contain up to 10 weight percent clumping agent selected from the group of water absorbent polymers, corn starch, gelatin, gluten and dried plants of the Plantago family. In addition 5 to 25 wt % ammonia absorbing zeolite may be added for odor control. The odor control agent is an absorbent only for ammonia and does not provide odor control since ammonia is not immediately formed.
[0015] U.S. Pat. No. 5,634,431 to Reddy, et al. discloses odor inhibiting pet litter. The addition of urease negative bacteria to sodium smectite clay minerals in pet litter inhibits growth of urease positive bacteria for a period of several days, thereby retarding formation of ammonia and other obnoxious odors. Approximately fifty percent sodium bentonite in the litter causes the litter to clump upon wetting, maintaining the urea in contact with the treated clay and also serving as a buffer to favor growth of the urease negative bacteria. This composition entirely relies on inhibiting ammonia formation and does not provide immediately a pleasant scent.
[0016] U.S. Pat. No. 5,806,462 to Parr discloses clumping animal litter. The animal litter is particularly suited for cats. A gelatin solution and a dry adhesive is sprayed onto the granules. The gelatin solution provides enough dampening to adhere the adhesive particles to the clay particles. Because the gelatin sets quickly, it does not provide so much wetting as to activate the adhesive. Therefore, the adhesive retains its adhesive properties and, together with the gelatin, causes the litter to clump when wetted by an animal. This clumping cat litter formulation provides no odor control.
[0017] U.S. Pat. No. 5,975,019 to Goss, et al. discloses clumping animal litter. The clumping animal litter utilizes the interparticle interaction of a sodium bentonite, a swelling clay, with a non-swelling clay material. Preferably, sixty percent (60%) by weight, or less, composition of sodium bentonite is used after the judicious selection of particle size distribution such that the mean particle size of the non-swelling clay material is greater than the mean particle size of the sodium bentonite. In addition, an organic clumping agent, such as a pregelatinized corn starch can be combined with the sodium bentonite/clay mixture to enhance clumping properties. This clumping clay litter does not control odor.
[0018] U.S. Pat. No. 5,992,351 to Jenkins discloses clumpable animal litter with improved odor control. The clumpable animal litter with improved odor control comprises a) water-swellable clay particles capable of adhering other such particles upon contact with moisture; and b) an odor controlling-effective amount of a boron compound of a composition di-alkali metal tetraborate n-hydrate, wherein n is 4, 5 or 10, which controls odors arising from the contact of said clay particles with moisture.
[0019] U.S. Pat. No. 6,206,947 to Evans, et al. discloses a process for making an animal litter comprising gypsum, aluminum sulfate and urea. The animal litter composition is an agglomerated or compacted calcined calcium sulfate absorbent. The animal litter composition is screened to a particle size between 6 mesh and about 100 mesh and an effective amount of a binder such as a clay, lignin or starch is added to the calcium sulfate to assist the calcium sulfate to pelletize. This is a gypsum composition that is agglomerated using aluminum sulfate and urea to chemically combine with gypsum. There is no odor control in this clumping litter composition.
[0020] U.S. Pat. No. 6,253,710 to Ward, et al. discloses odor control for animal litter. It uses an odor control liquid and an aerosolized composition for deodorizing and controlling the odor of animal wastes. The liquid and aerosolized composition comprises a non-aqueous volatile carrier and an odor control agent. The liquid and aerosolized composition can be applied in liquid form directly to the animal litter and/or the animal container and/or the animal waste. The litter container may be sprayed with a powdered release agent which may be talc, of talc, inorganic silicone and magnesium powders, sodium bicarbonate, chlorophyll, sodium dihydrogen phosphate, potassium acid phthalates, or their mixtures preventing the stickiness of the odor controlling liquid. The liquid mixes with the litter product and constantly evaporates. Consequently, the odor control agent continuously disseminates and becomes quickly exhausted.
[0021] Number of prior art patents relate to micro encapsulation of fragrances and these fragrances are continually released. Some of the patents disclose encapsulation wherein the fragrance is prevented from slow release by having an impervious cell wall.
[0022] U.S. Pat. Nos. 6,375,983 and 6,558,706 to Kantor, et al. discloses microencapsulated fragrances and method for preparation. This encapsulated fragrance has a microcapsule from which the fragrance is controlled can be released by exposing the encapsulated fragrance to a solution of a predetermined pH. The encapsulant for the microcapsule is a copolymer of acrylic acid monomer and a one ethylenically unsaturated polymerizable monomer. The copolymer further comprises a pH sensitive carboxyl group or an amine group. The microcapsule encapsulant dissolves when it contacts a solution of appropriate pH. This encapsulated fragrance is not indicated to be usable in a litter.
[0023] U.S. Pat. Nos. 6,375,983 and 6,558,706 to Kantor, et al. disclose microencapsulated fragrances and method for preparation. This encapsulated fragrance has a microcapsule from which the fragrance is controlled can be released by exposing the encapsulated fragrance to a solution of a predetermined pH. The encapsulant for the microcapsule is a copolymer of acrylic acid monomer and a one ethylenically unsaturated polymerizable monomer. The copolymer further comprises a pH sensitive carboxyl group or an amine group. The microcapsule encapsulant dissolves when it contacts a solution of appropriate pH. This encapsulated fragrance is not indicated to be usable in a litter.
[0024] U.S. Pat. No. 6,369,290 to Glaug, et al. discloses time release odor control composition for a disposable absorbent article. This disposable absorbent article is provided with a odor control powder which is unscented in a dry state and releases a burst of fragrance when wetted, such as by human waste. The powder contains a relatively small amount of fragrance oil, such as 0.5% to 4% by weight, to prevent skin irritation to the wearer. The small amount of fragrance oil is microencapsulated in a starch, which constitutes from about 50% to 90%, and preferably about 70%, of the total weight of the particles. Sodium bicarbonate is also included in the particulate odor control material in an amount ranging from 5.0% to 45%, and preferably about 25% by weight, of the total weight of the particles. The sodium bicarbonate promotes skin wellness by controlling the pH levels of the fragrance oil, starch and human waste. A small amount of flow agent is also contained in the particulate odor control material. The odor control composition is indicated to be used in a disposable absorbent article for absorbing and containing body fluids, comprising an absorbent core and an odor control powder, both located between a fluid pervious cover sheet and a fluid impervious or hydrophobic backing. The odor control powder is substantially unscented when in an initial dry condition, before being wetted, and is capable of releasing a mild fragrance when wetted. The composition is not indicated to be usable in an animal litter.
[0025] U.S. Pat. Nos. 6,638,591 and 6,902,817 to Bowen, et al. discloses membrane permeable to aromatic products. This multilayer structure with improved permeation for atmospheric diffusion of aromatic products has a structure with a first permeable layer of a blend of very low density polyethylene and low density polyethylene, a second permeable layer of low density polyethylene, a third permeable layer of a blend of very low density polyethylene and low density polyethylene, a fourth permeable layer of a material selected from a blend of low density polyethylene and a modified polyolefin and a release layer comprising ethylene vinyl alcohol copolymer. The multilayer wall structure of a close extruded cell releases aromatic compound at a slow rate.
[0026] U.S. Pat. No. 7,235,261 to Smith, et al. discloses a controlled release encapsulation. The controlled release encapsulated dry powder is formed by an emulsion having a fully hydrolyzed polyvinyl alcohol polymer, a hydrophobic silica, a modified corn starch, and a fragrance oil. The fragrance oil is emulsified in water and spray dried to evaporate the water obtaining the encapsulated dry powder. The dry powder with encapsulated fragrance oil provides controlled release of the fragrance, presumably due to cracks and irregularities present in encapsulation wall.
[0027] There remains a need in the art for a cat or animal litter composition containing ingredients that release a pleasant scent only after the cat or animal uses the litter. Also needed in the art is an animal litter composition that does not overpower the environment with litter scent. Further needed is an animal litter composition that eliminates the malaise odor of common litter boxes.
SUMMARY OF THE INVENTION
[0028] The present invention provides a litter formulation for a cat or animal litter having fragrance-scented balls that are encapsulated in a capsule shell that either breaks under the weight of the animal and/or swells or degrades in the presence of animal urine, thereby releasing scented fragrances. The breakage of the capsule generally occurs when the animal handles the litter and the water-soluble capsule coating swells, disintegrates or dissolves in water when the animal urinates on the litter. The fragrance-scented balls with encapsulated capsule shell walls are added to an unscented litter, causing the overall litter to be generally unscented; but to release a fragrance when the animal uses the litter box. The litter in the litter box thus does not produce overpowering smell even in closed, temperature-controlled rooms. However, the scent from the scent-fragrance balls is released in those regions that are either disturbed by the animal during litter box usage or from the places where the animal urine permeates in the litter box. This fragrance is delivered at substantially the same time as the cat or the animal disturbs or urinates in the litter, creating an environment free from unpleasant odor.
[0029] Generally stated, the fragrance-scented balls have liquid, semi-solid or solid fragrance oil that is coated with a capsule shell wall that contains the fragrance oil. The vapor pressure of fragrance oil is generally greater than one atmosphere at room temperature so that the fragrance is released when the oil is open to air. The microcapsule cell walls may be made from polymers such as polyvinyl alcohol that is impermeable to liquids but is permeable to vapors produced from the fragrance oil. Thus, the fragrance oil slowly releases the fragrance as a function of time and the quantity of fragrance oil within the microcapsule decreases as a function of time. When the all the fragrance contained therein is released, the microcapsule no longer releases any fragrance. When this microcapsule is mixed with an unscented litter, the fragrance scent is always released similar to a conventional animal litter that has a fragrance scent or masking odor mixed therewithin. A closed room becomes overpowered with the fragrance scent from the animal litter and may be objectionable to most people.
[0030] In a first embodiment, the capsule walls may be formed from a polymer that is impermeable to both liquid fragrance oil and fragrance oil vapors. Polyethylene polymer and wax capsule shell walls provide this functionality. However, the capsule wall surfaces are readily ruptured when the animal disturbs the litter, thus releasing the fragrance oil scent. There are a number of polymer compositions that are impervious to liquid fragrance scent oil and its vapors. These polymer compositions are generally produced by a cross-linking reaction between a monomer composition that surrounds the fragrance scent oil in a medium such as water. The monomer reacts with a cross linking agent, creating an impervious microcapsule wall surrounding the fragrance scent oil.
[0031] In a second embodiment, the capsule walls are made from a water-soluble compound such as starch or pre-digested starch that swells and breaks down when the animal urine contacts the fragrant oil capsule. The fragrance scent oil is mixed as an emulsion with water that has hydrolyzed starch based composition such as hydroxymethyl cellulose. When the composition is spray dried, the starch composition forms an impervious covering surrounding the fragrance oil. The microcapsule wall readily ruptures when handled by the animal during use of the litter box, an act that will release the fragrance scent. When the animal urinates on the litter, the water from the urine softens and swells the starch based microcapsule cell wall releasing additional fragrant scent in the area wetted by the animal urine. If the litter of the clump forming type, the permeation urine is limited and the fragrant scent is only released in this wetted region.
[0032] In a third embodiment, the microcapsule with PVA or other vapor permeable membrane is made surrounding a fragrant scent oil is provided with an overcoat of starch based composition essentially blocking the vapor permeability of the microcapsule walls. When a microcapsule of the third embodiment is wetted by urine the fragrance scent is released at a rate the PVA microcapsule cell wall delivers the fragrance. In a similar manner, when the animal disturbs the microcapsule of the third embodiment, the starch impervious layer is compromised, thus releasing the fragrance.
[0033] The litter may be provided in the form of an unscented litter mixed intimately with fragrant scent capsules of the first, second or third embodiment. On the other hand, the fragrant scent capsules may be marketed separately and are to be mixed with unscented litter by the user. The fragrant scented capsules are mixed with unscented litter in a proportion ranging from one hundredth of a percent to one percent on a weight basis. The unscented litter may be self-clumping for restraining the movement of urine through the litter to a large distance.
[0034] The fragrance oil used may be selected from a number of natural or synthetic fragrances as well as odor masking compounds. Anti-microbial agents may also be included in the microcapsule either in combination with the fragrance oil or as separate microcapsules.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] The invention will be more fully understood and further advantages will become apparent when reference is had to the following detailed description of the preferred embodiments of the invention and the accompanying drawing, in which:
[0036] FIG. 1 is a schematic diagram showing a fragrant-scented microcapsule comprising a fragrance oil covered with a microcapsule cell wall layer; and
[0037] FIG. 2 is a diagrammatic representation of the process of manufacturing a fragrance scent microcapsule for use in a litter box as an additive.
DETAILED DESCRIPTION OF THE INVENTION
[0038] This invention relates to a microcapsule additive containing fragrance scent oil for litters used by cats and other animals. The microcapsule additive releases an odor neutralizing, pleasant fragrance when the litter is used by a cat or animal. The walls of the microcapsule may break during handling by the animal using the litter box. Alternatively, contact of microcapsules with animal urine swells and disrupts the microcapsule cell walls, releasing the fragrant scent contained therewithin. The litter with the microcapsule additives is nominally fragrance free until used by the animal. As such, the litter does not over power the environment of a closed room with litter scent. Generally stated, the additive is a fragrant-scented microcapsule, which may be added to the litter or, alternatively, may be packaged therewith. The fragrant-scented microcapsule includes fragrance oil in the form of a liquid, semi-solid or solid which has a vapor pressure greater than one atmosphere as the fragrance is evaporated and consumed. If the microcapsule cell wall is permeable to vapors while being impervious the liquid fragrance oil, the evaporation of the fragrance is similar to a time-release microcapsule and is quickly consumed. The evaporated fragrance will saturate a closed heated or air conditioned room with the litter scent, a situation not acceptable to most users. The present invention has a microcapsule wall that is generally impervious to both fragrant scent oil and its vapors until is either broken or wetted by water which swells and disrupts the cell walls. Preferably, the fragrant-scented microcapsule additive is used in conjunction with an unscented clumping litter, which reduces or minimizes the spreading of urine due to the clumping action. The clumping litter generally uses a mixture of swelling clay composition together with non-swelling clay composition as discussed in U.S. Pat. No. 5,975,019 to Goss, et al. or a mixture of gypsum with clay as discussed in U.S. Pat. No. 4,459,368 to Jaffee, et al.
[0039] Generally stated, the invention involves the use of fragrant-scented microcapsules, which have fragrance scent oil in the form of liquid, semi-solid or solid. These microcapsules with a vapor pressure greater than one atmosphere and releases fragrance, when covered with a vapor pervious microcapsule cell wall. If a vapor permeable cell wall such as polyvinyl alcohol is used, it is further covered by an impervious layer of starch based composition. The fragrance may be an odor neutralizing or masking compound or a pleasant smelling fragrance. A typical odor neutralizing or masking compound is lauryl methacrylate (sold under trade name METAZENE by Pestco Company). The masking compound is dissolved in acetone, a non-aqueous volatile carrier. Representative examples of fragrance components generally include, but are not limited to: volatile phenolic substances (such as iso-amyl salicylate, benzyl salicylate, and thyme oil red); essence oils (such as geranium oil, patchouli oil, and petitgrain oil); citrus oils; extracts and resins (such as benzoin siam resinold and opoponax resinold); “synthetic” oils such as Bergamot 37 and 430, Geranium 76 and Pomeransol 314, and Powder Mask CE-32907); aldehydes and ketones (such as beta-methyl naphthyl ketone, p-tert-butyl-a-methyl hydrocinnamic aldehyde and p-tert-amyl cyclohexanone); polycyclic compounds (such as Coumarin and beta-naphthyl methyl ether); esters (such as diethyl phthalate, phenylethyl phenylacetate). Fragrances also include esters and essential oils derived from floral materials and fruits, citrus oils, absolutes, aldehydes, etc. and alcohols (such as dimyrcetol, phenylethyl alcohol and tetrahydromuguol). Other fragrances include Cherry, Bonsai, Watermelon, Apple, Almond blend, Gamma, Cinnamon, Orange, Lemon, Eucalyptus, Honey Suckle, Citrus Orange, Ambient Neutralizer and Pine Oil.
[0040] Generally the fragrances are dissolved in aqueous or non-aqueous carrier and the microcapsule cell wall is provided by well known means. Typical microcapsule formation processes include physical methods or chemical methods. Physical methods include processes such as pan coating, air-suspension coating, centrifugal extrusion, vibrational nozzle and spray drying. Chemical methods include processes of interfacial polymerization, in-situ polymerization and matrix polymerization. Regardless of the methods selected, the microcapsule cell walls have to be compromised when disturbed by an animal and/or when wetted by urine releasing the fragrant scent oil contained therewithin.
[0041] The following examples are provided to more completely describe the properties of the present invention. The specific techniques, conditions, materials, proportions and reported data set forth to illustrate the principles and practice of the invention are exemplary only and should not be construed as limiting the scope of the invention.
Example 1
[0042] ARA Fragrance Cores manufactures microcapsules that contain fragrance scented oils using a proprietary hybrid of technologies to develop the matrix mold concept. The fragrance oils are first treated with a polymer material then the mixture is subjected to a cross-linking step which solidifies the mixture, entrapping the fragrance oil in a thin coating. This coating is permeable to the vapors of the fragrance, and determines the release rate of the fragrance. The fragrance oil contained therein is selected from Cherry, Bonsai, Watermelon, Apple, Almond blend, Gamma, Cinnamon, Orange, Lemon, Eucalyptus, Honey Suckle, Citrus Orange, Ambient Neutralizer and Pine Oil. The outer surface of the microcapsule is coated with water disintegrating coating such as starch or hydroxyethylcellulose. The microcapsules are mixed with unscented clumping animal litter and fragrance scent is released when the microcapsule is ruptured or treated with water.
[0043] FIG. 1 is a schematic diagram showing a fragrant-scented microcapsule 10 having central fragrance scent oil 11 encapsulated within the cell wall of the microcapsule 12 . The fragrance oil 11 is shown here as a liquid while it may be a semi-solid or solid and has a vapor pressure greater than one atmosphere. The impervious microcapsule cell wall 12 is manufactured from polymers including polyethylene, polyurethane, or other suitable polymeric materials. The microcapsule substrate has a linear dimension in the range of 1000 to 5000 microns, and the microcapsule cell wall is in the range of 25 to 250 microns. The microcapsule cell wall is selected to prevent the evaporation of the fragrance scent oil. It breaks under load when a cat or animal uses a litter box containing litter with fragrance scent oil, and resists deterioration by urine and other animal excrement.
[0044] Referring to FIG. 2 , there is shown generally at 20 a diagrammatic representation of the process of manufacturing a fragrance scent microcapsule. In step 1 , the liquid, semi-solid or solid fragrance scent oil is broken into appropriate sized droplets of chunks. In step 2 , a starch coating or suitable polymer cross linking coating is applied over the individual droplets or chunks to create the microcapsule cell wall. This may be accomplished by a liquid immersion process (not shown) or use of a spray process, as shown, that applies a wall coating to form microcapsules. In step 3 , the fragrance scent microcapsule cell walls are hardened by a heating process, which may be carried out in a heated rotating drum or barrel. The rotation of the drum or barrel keeps the individual microcapsules apart so that they do not stick to each other.
[0045] Significant advantages are realized by practice of the present invention. The key components of the odor control additive for animal litter include, in combination, the features set forth below;
1. a odor control additive for animal litter comprising a plurality of with fragrance scent microcapsules; 2. each fragrance scent microcapsule having a central portion with a fragrance scent oil in the form of a liquid, semi-solid or solid having a vapor pressure greater than one atmosphere; 3. each fragrance scent microcapsule having cell wall that is impervious to fragrance vapor substantially preventing evaporation of the fragrance scent oil contained within microcapsule; 4. The microcapsule cell wall capable of being broken when handled by an animal and or swells and disrupts when contacted by animal urine; 5. the microcapsule cell wall breaking under load of a cat or animal or disrupted by animal urine water while using a litter box containing the litter and fragrance scent microcapsule, triggering release of the fragrance.
[0051] The process of manufacturing a fragrant-scented ball includes the steps set forth below:
1. selecting a fragrance oil which may be a liquid, semi-solid or solid with a fragrance vapor pressure greater than one atmosphere; 2. providing microcapsule wall encapsulant that is impervious to the fragrance-scent vapor and is capable of being broken by an animal weight or disintegratable by animal urine; 3. packaging the microcapsule filled with fragrance scent oil as an additive for unscented litter that may be optionally clump forming or mixing them with a unscented litter formulation that is packaged for sale.
[0055] Having thus described the invention in rather full detail, it will be understood that such detail need not be strictly adhered to. For example, a neutralizing agent can be used in place of a fragrance to absorb and thereby irradiate odor otherwise produced by urine or defecation on the litter. Upon release, a natural bacteria producing enzyme contained by the neutralizing agent, reproduces itself continuously to eliminate all liter odor. Fragrance-containing tablets, pellets, power or sheets can be used to overpower or neutralize the odor produced by garbage containing vessels. These and additional changes and modifications may suggest themselves to one skilled in the art, all falling within the scope of the invention as defined by the subjoined claims. | An odor control additive present in a litter formulation provides release of fragrance or odor masking scent only when litter is used by a cat or other animal within a litter box. The odor control additive comprises a plurality of fragrance scent microcapsules that contain fragrance scent oil. This central, fragrance scent oil is encapsulated in a microcapsule cell wall, which prevents evaporation of the fragrance scent oil and prevents overpowering of litter smell in a closed room resembling an unscented litter composition. When cat or animal enters the litter box, a load is applied to the fragrance scent microcapsules, which readily breaks releasing the fragrance contained therein. The fragrance scent microcapsule cell walls also degrade by swelling and degradation when wet by animal urine thereby releasing fragrance. Fragrance evaporating from the ruptured microcapsules provides odor control and a pleasant scent. | 0 |
BACKGROUND OF THE INVENTION
1. Field
This invention is directed generally to asphalt concrete performance testing equipment and in particular to those devices that attempt to predict the resistance of a designed asphalt concrete mixture to permanent plastic deformation, commonly referred to as rutting.
Asphalt concrete is the most common type of pavement surface material used in the United States. Due to the large investments most states have in asphalt pavements, it follows that they expend a significant amount of resources optimizing mix designs to achieve superior products. To facilitate the design process, different parts of the country design asphalt concretes to resist the types of failures that they most frequently encounter. Consequently, in warmer climates a major design consideration is the resistance a designed mix will have to rutting. It is cost effective to test designed mixes before they are placed to obtain information that will aid the engineer in predicting how they will perform after they are in service. Decades of research have yielded several pieces of equipment that test laboratory samples in the hope of predicting the tendency a designed mix will have to experience permanent plastic deformation while in service.
1. Description of the Prior Art
Equipment recently developed attempts to quantify the rutting susceptibility of asphalt concrete mixes. Loosely based on a European design, currently utilized laboratory equipment consists of an environmental chamber and a load beam. While a test specimen is environmentally conditioned to a temperature that approximates a maximum service condition, a loaded wheel rolls back and forth along a stationary beam. Each time the wheel passes over the sample, a load repetition is applied. As many loads are applied, the sample experiences permanent plastic deformation. Test results reflect the magnitude of the measured rut following a fixed number of load repetitions. The primary difference between the American and European devices is that the American device uses an inflated tube between the wheel and the sample to control contact pressure.
The equipment currently in use is limited in a number of ways. The most notable drawback is the applicability of test results. There is considerable debate regarding the performance similarities between a specially prepared laboratory sample and an in-place roadway pavement. Some feel that it is impossible to compact the small rectangular samples in a laboratory environment in such a way that they actually represent the mix as designed and constructed with respect to such parameters as confining stress, density and void ratio.
Critics of the current process note that simulations at temperatures that are representative of actual summertime service temperatures cannot be run without experiencing premature failures as evidence to support this position. Additionally, the special equipment that is required can make the process financially prohibitive.
Further, excessive time may be required to conduct the test as the load wheel must change direction between each application. For samples that are designed to be rut resistant, a successful proof test may take many hours to complete. This limitation would hinder the use of such devices for field quality control, where additional test time may mean that a significant amount of inferior pavement has been placed.
The above mentioned equipment, while providing a method for approximating the rutting susceptibility of an asphalt, leaves substantial room for improvement, For examples a machine that could utilize the standard design specimens (see AASHTO T 245) would avoid the question of similarity between rutted samples and constructed pavements. Also, the problem of confining stress could be completely avoided if there were a way to test the specimen without extracting it from its compaction mold. Consequently, existing compaction equipment could be utilized to prepare the test specimens, thereby avoiding the cost of new compaction equipment entirely, Further, use of existing environmental conditioning equipment would make a rut testing device more attractive for industry-wide use. Due to the size of today's standard samples and existing equipment, however, a radically different approach to the method of applying the load repetition has to be considered.
SUMMARY OF THE INVENTION
The primary objective of the present invention is to provide a means of utilizing conventional compaction and temperature conditioning equipment to add a dimension of cost effectiveness to current methodology. Rather than using a wheel and beam configuration that requires special compaction and environmental control, a radical new load wheel has been designed and incorporated that allows the standard compaction specimen to be rut tested while the specimen is suspended within a common temperature bath. The load wheel assembly does not try to run off the sample because the design utilizes ten smaller wheels that are free-spinning.
Because the new device does not require the wheel to apply the load, decelerate, stop and reverse motions testing may be conducted in a relatively short period of time as several loads may be applied per second. Additional advantages of the present invention will be apparent after review of the figures included herein.
BRIEF DESCRIPTION OF THE DRAWINGS
For the purpose of illustrating the invention, there is shown in the drawings a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.
FIG. 1 is a perspective view of the invention, which the inventor intends to call the RUTMETER as seen free standing, without part numbers and not attached to a common temperature bath.
FIG. 2 is a perspective view of the load application wheel comprising a portion of FIG. 1.
FIG. 3 is a perspective view of the process control box comprising a portion of FIG. 1.
FIG. 4 is a perspective view of tile freestanding chassis comprising a portion of FIG. 1.
FIG. 5 is a device as shown in FIG. 1 with labeled part numbers.
FIG. 6 is an exploded view of FIG 5.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the following claims rather than the above described specifications or drawings as indicating the scope of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
Referring to FIG. 1, there is illustrated a RUTMETER drawn to scale that incorporates the lead wheel assembly, process control box, and chassis as components of this application. The lead wheel assembly consists of those numbered parts in FIG. 2 where the obvious departure from prior art is seen in part numbers 31 through 35 that comprise the lead wheel itself. Rather than incorporating a single conventional wheel that travels back and forth across the top of a laboratory prepared specimen, FIG. 2 illustrates a series of free, spinning smaller wheels 31 that are mounted at 36 degree intervals via axle bolts 32 to two plates 33 so that tile entire assembly may spin in place while remaining in the same horizontal position on the top of a laboratory prepared specimen. The plates 33 are mounted to an axle 35 that is set in motion by a chain driven sprocket 34. The axle 35 attaches through guide holes 39 on either side to the travel arms 38 that are connected on their upper portion by a lead platform 37. A weight guide 36 sits atop the load platform to ensure that any donut weights added to apply a vertical lead do not slip off while The device is in motion. The pivot arms 38 that enable free near-vertical translation of the lead wheel are attached to a mounting bar 42 via guide holes 41 that are bolt-connected to angles 40 on either side. A commercially available gear motor 50 turns a sprocket 51 that sets the stationary lead wheel in circular motion via a chain 52.
The process control box shown in FIG. 3 of the preferred embodiment contains basic information needed to successfully document the response of laboratory prepared asphalt concrete samples subjected to repetitive loadings by the aforementioned lead wheel assembly (31, 32, 33, 34, 35). Electronics required to monitor the output of any attached displacement sensors are housed in a protective enclosure 60 that also serves as the permanent mounting location of LCD panels 61 on which data such as total number of loadings and displacement may be displayed. Displacement sensors of this nature are selected from commercial, off-the-shelf components and are chosen at the preference of those users skilled in the art. Single LED's 62 are used to indicate toggle settings that are controlled via button switches 63. As a laboratory prepared sample is loaded repetitively by the rotating, free-spinning wheel with a donut weight on its lead platform 37 above, electronics of the users choice monitor such information as lead count, vertical displacement, etc.
FIG. 4 has been included to illustrate the preferred embodiment of the chassis. Here it is seen that a platform 24 supports the motor 50, travel arm mounting bar 42, and process control box 60. The platform 24 has machined grooves on its underside that are placed in such a manner that the top rim of many commonly used asphalt concrete temperature baths fits snugly inside them, thus enabling the chassis to simply "snap" on. In that no upward forces are generated during testing, no additional securing attachments are required. A basket 23 is used to support the laboratory prepared test specimen, which hangs underwater inside a temperature conditioning water bath that is provided separately. The sample is held in place by a shim 21 that fits snugly inside the specimen's compaction mold. As an added measure, an upper brace 22 holds the top of the sample in place as well. Side panels 25 ensure that the chassis will be rigid as the loads are applied thus creating vibration, and dolly wheels 26 have been provided so that the chassis may be easily placed in position over the sample conditioning bath that must be provided separately to facilitate testing.
The part labeling system utilized in FIGS. 2 through 4 was superimposed onto FIG. 1 to create FIG. 5 which has been included for clarification purposes. Likewise. FIG. 6 has been included as an exploded view of FIG. 5.
In normal operation, laboratory technicians will prepare asphalt concrete samples as per AASHTO T 245. Instead of jacking the compacted specimens out of their molds, technicians will jack the sample up until its top is approximately flush with the top of the compaction mold. At this time, the specimen and its mold will be inserted into the submerged basket 23 that is underwater when the platform 24 is attached to a conventional water temperature bath (preheated to simulate a maximum summer service temperature for in-place pavements). The shim 21 fits snugly into the bottom of the metal compaction mold to hold it and the sample in place, with the help of the upper brace 22. With the sample now underwater, the load wheel assembly (31, 32, 33, 34, 35) is lowered onto the test surface and a vertical load is applied by stacking a weight onto the load platform 37 via the weight guide 36. The process control box (60, 61, 62, 63) is activated and the commercially available motor 50 sets the load wheel assembly (31, 32, 33, 34, 35) into its spinning motion. Since Ten free-spinning wheels 31 are located along the outer edge of the plates 33, ten separate near-vertical loadings are applied for each revolution to simulate traffic loadings on the final constructed roadway. As load transfer occurs between the smaller wheels 31, the pivot arms 38 translate up and down. While the loads are applied, the process control box counts the number of applications and monitors the cumulative vertical deformation, which is the simulated roadway wheelpath rut. Vertical deformation is monitored by means known to those skilled in the art, which would consist of commercially available off-the-shelf components. By comparing rutting curves for different designed mixes in the laboratory, engineers can determine which asphalt concrete mixes will be less likely to rat under full scale traffic after construction. An item of particular interest to engineers skilled in the art will likely be the number of load applications to induce 0.25 inches of permanent plastic deformation.
It is to be understood that although a small RUTMETER to test laboratory prepared test specimens has been shown, the unique load wheel design of the disclosed invention is equally well suited to test in-place pavements when constructed on a larger scale. Optimum materials and dimensions will depend in part on the intended application.
While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. | The disclosed machine is comprised of a chassis, process control box and load wheel assembly. The chassis is designed to attach to commercially available controlled temperature heating baths. The primary functions of the process control box are to distribute electrical power, monitor sensor responses to electrical inputs, and to control the overall operation of the load wheel assembly. The load wheel assembly applies multiple load applications while not rolling off the surface of a standard asphalt concrete specimen. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] None.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO A MICROFICHE APPENDIX
[0003] Not applicable.
FIELD OF THE INVENTION
[0004] The present invention relates to wellbore straddle-packer assemblies and methods of wellbore servicing with a pressurized fluid. More particularly, the present invention relates to a wellbore straddle-packer comprising a fluid saver assembly which, upon completion of the service operation, can be moved without venting pressurized fluid to the surface or waiting for the pressurized formation to bleed down.
BACKGROUND
[0005] As conventional sources of natural gas in North America decline while demand for this energy resource continues to grow, coal bed methane (CBM) has been identified as a viable alternative energy source. CBM is aggressively being extracted from multi-zone wellbore formations, and during production of these formations, downhole tools are used to deliver pressurized fluid to stimulate CBM production. In particular, the tool is set within the wellbore to isolate a formation zone, and pressurized nitrogen, or another type of fracturing fluid, is pumped through the tool into the isolated formation zone. The pressurized fluid acts to open or expand “cleats” within the coal seam, thus forming a communication channel through which the CBM can flow into the cased wellbore and then up to the surface.
[0006] Fracturing multi-zone CBM wellbore formations is often performed using downhole cup-style straddle-packers. Typically, pressurized nitrogen is pumped through a work string, such as coiled tubing, once these cup-style straddle-packers are set at a particular location within the wellbore. After fracturing a zone, it may be necessary to allow the pressurized formation to bleed down from the applied treatment pressure in order to unseat the cups and allow movement of the straddle-packer to the next zone to be fractured. The time required for this bleed down to occur may be 20 minutes, for example. Because many CBM wellbores have multiple zones to fracture, such as 15 to 20 zones, the total time waiting for formation bleed down to occur can be significant and increases the cost of fracturing the wellbore. As an alternative to waiting for the formation to bleed down, the pressurized fluid contained in the work string may be vented to the surface. This, however, wastes volumes of pressurized fluid that could otherwise be usefully injected into the CBM formations, thereby also increasing the cost of fracturing.
[0007] Besides the costs associated with venting pressurized fluid, and the time delays associated with waiting to move conventional straddle-packers, the cup-style sealing elements also have operational limits. As the demand for natural gas continues to rise, it has become necessary to drill deeper wellbores, and therefore, fracture formation zones at greater depths. As wellbore depths increase, cup-style sealing elements reach their operational pressure limits and no longer work reliably. Furthermore, the rubber material of the cups is incompatible with acids and other chemicals that may be contained in some wellbore servicing fluids. Even assuming the rubber cups are suitable for use operationally, venting of a pressurized fluid containing acids or chemicals to the surface may be prohibited due to environmental regulations. Where no such prohibition exists, repeated venting of a pressurized fluid containing acid or chemicals is still undesirable, as such venting can be expensive.
[0008] Therefore, due to the time and the increased operational cost associated with moving and re-seating typical cup-style straddle-packers during fracturing of multi-zone CBM well formations, the costs associated with venting pressurized fluid to the surface, the inability of cup-style sealing elements to function reliably at greater wellbore depths, and the incompatibility of rubber cups with acids and other chemicals, a need exists for a downhole tool designed for such operations. Specifically, a need exists for a straddle-packer assembly that reduces the time between fracturing multiple zones, does not require venting of pressurized fluid to the surface, is operational at greater wellbore depths, and is compatible with fluids containing acids and other chemicals.
SUMMARY OF THE INVENTION
[0009] In one aspect, the present disclosure relates to a method for performing a service operation within a wellbore extending into a formation comprising: sealing a first length of the wellbore to define a first isolated formation zone, flowing a pressurized fluid through a tubular string into the first isolated formation zone, and unsealing the first length of the wellbore without venting the pressurized fluid from the tubular string or awaiting depressurization of the first isolated formation zone. The method may further comprise: containing the pressurized fluid within the tubular string, moving the tubular string within the wellbore, sealing a second length of the wellbore to define a second isolated formation zone, flowing a pressurized fluid through the tubular string into the second isolated formation zone, and/or equalizing pressure between the sealed first length and an unsealed portion of the wellbore. In an embodiment, the method is performed in a single trip into the wellbore. The service operation may comprise fracturing a coal bed methane formation, and the pressurized fluid may comprise nitrogen, water, acid, chemicals, or a combination thereof.
[0010] In another aspect, the present disclosure relates to a method for performing a service operation within a wellbore extending into a formation comprising: running an assembly comprising a valve into the wellbore on a tubular string, fixing the assembly within the wellbore to define a first isolated formation zone, flowing a pressurized fluid through the valve into the first isolated formation zone, and closing the valve to contain the pressurized fluid within the tubular string. The method may further comprise: moving the assembly without venting the pressurized fluid from the tubular string or awaiting depressurization of the first isolated formation zone, equalizing pressure across the assembly before moving the assembly, re-fixing the assembly within the wellbore to define a second isolated formation zone, opening the valve, and/or flowing the pressurized fluid through the valve into the second isolated formation zone. In an embodiment, fixing the assembly comprises activating an upper seal and a lower seal within the wellbore to straddle the first isolated formation zone. In another embodiment, fixing the assembly further comprises activating an upper anchor and a lower anchor within the wellbore to straddle the first isolated formation zone. The method may further comprise bypassing pressure around the upper anchor when running the assembly into the wellbore.
[0011] In yet another aspect, the present disclosure relates to a method for performing a service operation within a wellbore extending into a formation comprising: running an assembly into the wellbore on a tubular string, engaging a wellbore wall with the assembly, setting down on the tubular string to activate upper and lower seals of the assembly against the wellbore wall to define an isolated formation zone, additional setting down on the tubular string to open a valve of the assembly, flowing a pressurized fluid through the valve into the isolated formation zone, and picking up on the tubular string to close the valve and contain the pressurized fluid within the tubular string. The method may further comprise additional picking up on the tubular string to move the assembly without venting the pressurized fluid from the tubular string or awaiting depressurization of the isolated formation zone. In various embodiments, the additional picking up opens a bypass flow path, the setting down on the tubular string activates a lower anchor of the assembly against the wellbore wall, and/or the additional setting down on the tubular string activates an upper anchor of the assembly against the wellbore wall.
[0012] In still another aspect, the present disclosure relates to an assembly connected to a tubular string for performing a service operation in a wellbore, the assembly comprising: a mandrel with a flowbore in fluid communication with the tubular string, an upper sealing device, a lower sealing device, a selectively operable valve that enables or prevents fluid communication between the flowbore and the wellbore, and a selectively closeable bypass flow path. The tubular string may comprise coiled tubing, and at least one of the sealing devices may comprise a plurality of sealing elements. The assembly may further comprise a continuous J-slot, drag blocks, an upper anchor, and/or a lower anchor. The upper anchor may comprise a plurality of spring-loaded buttons activated by pressure when the bypass flow path is closed, and the lower anchor may comprise a slip and cone system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] For a more detailed description of the present invention, reference will now be made to the accompanying drawings, wherein:
[0014] FIG. 1 provides a schematic side view, partially in cross-section, of a representative operational environment depicting a coiled tubing work string lowering one embodiment of a wellbore fluid saver assembly into a cased wellbore;
[0015] FIG. 2 provides a schematic side view of a wellbore fluid saver assembly located at a desired depth within the cased wellbore, with its upper and lower sealing elements set above and below a production zone, respectively;
[0016] FIGS. 3A through 3H , when viewed sequentially from end-to-end, provide a cross-sectional side view from top to bottom of one embodiment of a wellbore fluid saver assembly;
[0017] FIGS. 4A through 4F , when viewed sequentially from end-to-end, provide a cross-sectional side view of the wellbore fluid saver assembly of FIG. 3 in a run-in configuration;
[0018] FIGS. 5A through 5F , when viewed sequentially from end-to-end, provide a cross-sectional side view of the wellbore fluid saver assembly positioned at a desired depth in the wellbore and ready to set;
[0019] FIGS. 6A through 6F , when viewed sequentially from end-to-end, provide a cross-sectional side view of the wellbore fluid saver assembly anchored within the wellbore, a bypass flow path open, upper and lower sealing elements set, and a valve partially open;
[0020] FIGS. 7A through 7F , when viewed sequentially from end-to-end, provide a cross-sectional side view of the wellbore fluid saver assembly with the valve fully opened during fracturing;
[0021] FIGS. 8A through 8F , when viewed sequentially from end-to-end, provide a cross-sectional side view of the wellbore fluid saver assembly after fracturing is complete and the assembly has been picked up to be moved to the next formation zone; and
[0022] FIG. 9 provides a schematic cross-sectional side view of a J-slot and an interacting lug that form part of the wellbore fluid saver assembly.
NOTATION AND NOMENCLATURE
[0023] Certain terms are used throughout the following description and claims to refer to particular assembly components. This document does not intend to distinguish between components that differ in name but not function. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . ”.
[0024] As used herein, the term “tool” refers to the entire wellbore fluid saver assembly.
[0025] Reference to up or down will be made for purposes of description with “up”, “upper”, or “upstream” meaning toward the earth's surface or toward the entrance of a wellbore; and “down”, “lower”, or “downstream” meaning toward the bottom or terminal end of a wellbore.
[0026] In the drawings, the cross-sectional side views of the wellbore fluid saver assembly should be viewed from top to bottom, with the upstream end toward the top and the downstream end toward the bottom of the drawing.
DETAILED DESCRIPTION
[0027] A single embodiment of a wellbore fluid saver assembly, also referred to herein as “tool”, and its method of operation will now be described with reference to the accompanying drawings, wherein like reference numerals are used for like features throughout the several views. There is shown in the drawings, and herein will be described in detail, a specific embodiment of the tool that connects to a coiled tubing work string to inject high pressure fluid, such as nitrogen, into a formation for fracturing. It should be understood that this disclosure is representative only and is not intended to limit the wellbore fluid saver assembly to use with a coiled tubing work string, to nitrogen as the pressurized fluid, or to fracturing as the only wellbore service operation, as illustrated and described herein. One skilled in the art will readily appreciate that the wellbore fluid saver assembly disclosed herein may be connected to any type of work string for wellbore servicing in general, and not only for fracturing. Furthermore, one skilled in the art will understand that other wellbore servicing liquids and gases could be used instead of nitrogen, such as, for example, water, acid, chemicals, or a combination thereof.
[0028] FIG. 1 and FIG. 2 depict one representative wellbore servicing environment for the wellbore fluid saver assembly 200 . FIG. 1 depicts a coiled tubing system 100 on the surface 170 and one embodiment of a wellbore fluid saver assembly 200 being lowered on coiled tubing 150 into a wellbore 160 extending into a surrounding formation F. The coiled tubing system 100 may include a power supply 110 , a surface processor 120 , and a coiled tubing spool 130 . An injector head unit 140 feeds and directs the coiled tubing 150 from the spool 130 into the wellbore 160 .
[0029] FIG. 2 depicts the wellbore fluid saver assembly 200 of FIG. 1 after it has been lowered to a desired depth and positioned in the wellbore 160 . Specifically, upper sealing elements 17 and lower sealing elements 61 , as well as anchoring upper buttons 9 and anchoring lower slips 45 , are shown set against a casing 165 lining the wellbore 160 . As set in this position, the tool 200 straddles a production zone “A” of interest, which has previously been perforated 300 through the casing 165 and cement 167 into the surrounding formation F. The upper sealing elements 17 and the lower sealing elements 61 of the tool 200 seal against the casing 165 to isolate the production zone A prior to fracturing.
[0030] Referring now to FIGS. 3A through 3H , these cross-sectional side views depict the individual components of one embodiment of a wellbore fluid saver assembly 200 . In particular, when viewed from end to end, FIGS. 3A through 3H represent a cross-sectional side view of the tool 200 from top to bottom. The assembly 200 comprises three partially concentric tubular systems 210 , 220 , 230 that reciprocate axially with respect to one another, and a lug assembly 68 at its lower end. An inner tubular system 210 comprises a threaded coupling 1 , a top mandrel 2 , a ported mandrel 30 , and a lower collet 36 as depicted in FIGS. 3A through 3F . The threaded coupling 1 includes a box end 11 for connecting to the coiled tubing 150 and threads into the upper end of the top mandrel 2 , which in turn threads into a lock ring 25 and the upper end of the ported mandrel 30 as shown in FIG. 3D . An upper collet ring 26 surrounds the lower end of the top mandrel 2 and axially resides between the lock ring 25 and the ported mandrel 30 , which threads at its lower end into the lower collet 36 as shown in FIG. 3E . The ported mandrel 30 comprises valving ports 60 , bypass ports 66 and a flow blocking section 31 that terminates an inner flowbore 15 extending through the threaded coupling 1 , the top mandrel 2 , and the ported mandrel 30 .
[0031] A middle tubular system 220 surrounds the inner tubular system 210 and comprises a top sleeve cap 3 , a top sleeve 4 , a hold down body 8 , a seal element mandrel 23 , and an upper collet 28 as shown in FIGS. 3A through 3D . The top sleeve cap 3 threads into the top sleeve 4 , which in turn threads onto the hold down body 8 . The lower end of the hold down body 8 threads into a first gauge ring 16 and onto the seal element mandrel 23 . The hold down body 8 includes a plurality of recesses within which are disposed piston buttons 9 biased to a retracted position by piston springs 10 . The opposite end of the seal element mandrel 23 is threaded into the upper collet 28 as shown in FIG. 3D . The seal element mandrel 23 supports an upper set of sealing elements 17 , with each individual sealing element 17 separated by spacers 18 . The set of sealing elements 17 and spacers 18 reside axially between first and second gauge rings 16 , 14 as shown in FIGS. 3B and 3C .
[0032] Referring now to FIGS. 3C through 3H , an outer tubular system 230 surrounds a portion of the middle tubular system 220 and a portion of the inner tubular system 210 . The outer tubular system 230 comprises a spring housing 20 , a sleeve cap 22 , a connecting sleeve 29 , a valve body 33 , a ported sub 34 , a lower collet housing 35 , a bottom nipple 41 , a lower packer top sub 42 , a lower packer mandrel 55 and a bottom sub 56 . The spring housing 20 threads into the second gauge ring 14 , and a Belleville spring 21 is positioned axially between the spring housing 20 and the upper end of the sleeve cap 22 as shown in FIG. 3C . The lower end of the sleeve cap 22 threads into the connecting sleeve 29 , which in turn threads onto the upper end of the valve body 33 as shown in FIGS. 3C and 3D . The lower end of the valve body 33 threads to the ported sub 34 , which in turn threads into the lower collet housing 35 as shown in FIG. 3E . The lower end of the lower collet housing 35 threads onto the bottom nipple 41 , and a lower collet ring 37 is shown axially positioned between the bottom nipple 41 and a shoulder 32 on the inner surface of the lower collet housing 35 as shown in FIG. 3F . A shear ring 38 receives a shear screw 39 , which extends through the bottom nipple 41 to lock the outer tubular system 230 with respect to the inner tubular system 210 .
[0033] As depicted in FIGS. 3F and 3G , the bottom nipple 41 is provided with lower threads 46 to connect into a box end 48 of the lower packer top sub 42 . A third gauge ring 43 threads between the lower packer top sub 42 and the lower packer mandrel 55 . A fourth gauge ring 51 threads onto a cone 44 that is used to activate one or more slips 45 . A lower set of sealing elements 61 resides between the third gauge ring 43 and the fourth gauge ring 51 with element spacers 18 provided between each of the individual sealing elements 61 . A continuous J-slot 62 is formed into the outer surface of the lower packer mandrel 55 as shown in FIG. 3G . The lower end of the lower packer mandrel 55 threads into the bottom sub 56 as shown in FIG. 3H . The wellbore fluid saver assembly 200 also comprises a plurality of O-rings 6 for sealing between components of the tubular systems 210 , 220 , 230 , as well as a plurality of set screws 7 for locking the various components of the tubular systems 210 , 220 , 230 together as depicted in FIG. 3A through 3H .
[0034] Referring again to FIG. 3H , the lug assembly 68 comprises a slip cage 47 , a lug ring 49 and a drag block body 54 containing a drag block 52 and a spring 53 . The lug assembly 68 is disposed about the lower packer mandrel 55 and connects to the J-slot 62 by a lug 50 extending from the lug ring 49 . The drag block body 54 threads into the slip cage 47 , and the slips 45 extend upwardly from the slip cage 47 for interaction with the cone 44 . The drag block 52 is attached to the drag block body 54 and biased radially outwardly by a drag block leaf spring 53 that is located in a cavity between the drag block body 54 and the drag block 52 . The lug ring 49 and the lug 50 reside in recesses along the inner surface of the drag block body 54 , with the lug 50 extending to engage the continuous J-slot 62 . The interaction between the lug 50 and the continuous J-slot in various configurations of the tool 200 is also depicted in FIG. 9 and will be discussed in more detail herein.
[0035] Referring again to FIGS. 3B through 3E , the wellbore fluid saver assembly 200 also comprises a number of ports that provide various flow paths through the assembly 200 . As shown in FIG. 3E , the ported mandrel 30 comprises inner valving ports 60 and the ported sub 34 comprises outer valving ports 63 . As such, the ported mandrel 30 and ported sub 35 comprise a valve 67 that is open when the inner valving ports 60 and the outer valving ports 63 are at least partially aligned, and that is closed when these ports 60 , 63 are totally out of alignment. Accordingly, when the valving ports 60 , 63 are aligned, they allow communication of pressurized nitrogen 180 from the flowbore 15 to the surrounding wellbore 160 .
[0036] The ported mandrel 30 also includes bypass ports 66 that interact with the outer valving port 63 when the valve 67 is closed to allow fluid communication along a lower bypass flow path 12 between a lower flowbore 24 and the wellbore 160 . Referring to FIGS. 3B through 3D , an upper bypass flow path 69 is provided in a gap between the inner tubular system 210 and the middle tubular system 220 , and this upper bypass flow path 69 is defined by bypass ports 70 , 71 , and 72 that are located in the top sleeve 4 , the upper collet 28 , and the connecting sleeve 29 , respectively. Like the lower bypass flow path 12 , the upper bypass flow path 69 is also open when the valve 67 is closed.
[0037] As shown in FIGS. 3B and 3E , in addition to the components introduced above, there are also three molded seals 5 , 64 , 65 that are important for directing the flow of pressurized nitrogen 180 through the bypass flow paths 12 , 69 , or through the valve 67 , or both. The upper molded seal 5 is located near the interface between the top sleeve 4 and the hold down body 8 as shown in FIG. 3B . When the upper bypass flow path 69 is open, namely, when flow is permitted through ports 72 , 71 and 70 , the upper molded seal 5 prevents such flow from actuating the piston buttons 9 . The central molded seal 64 is located between the valve body 33 and the ported sub 34 , and the lower molded seal 65 is located near the interface between the ported sub 34 and the lower collet housing 35 as shown in FIG. 3E . Both of these molded seals 64 , 65 prevent the loss of pressurized nitrogen 180 from the valve 67 when the valve 67 is open and the bypass flow paths 12 , 69 are closed.
[0038] The wellbore fluid saver assembly 200 assumes various operational configurations during fracturing of the formation F surrounding the wellbore 160 , which include not only the actual fracturing process, but also run-in and movement of the tool 200 from one production zone to the next. The remaining figures illustrate the sequential operational configurations of the wellbore fluid saver assembly 200 during wellbore fracturing. In general, as will be described in more detail herein, FIGS. 4A through 4F depict the wellbore fluid saver assembly 200 as configured during run-in; FIGS. 5A through 5F depict the assembly 200 located adjacent to the production zone of interest and ready to set; FIGS. 6A through 6F show the tool 200 anchored, the upper and lower sets of sealing elements 17 , 61 set, and the valve 67 partially open to allow communication of the pressurized fluid 180 between the flowbore 15 and the surrounding wellbore 160 ; FIGS. 7A through 7F depict the valve 67 fully open, as it will be during the fracturing operation; and FIGS. 8A through 8F depict the valve 67 closed after completion of the fracturing operation with the tool 200 being moved by the coiled tubing 150 to the next production zone or being removed from the wellbore 160 .
[0039] Referring now to FIGS. 4A through 4F , the tool 200 is shown in its run-in configuration, i.e. the configuration of the tool 200 as it is lowered or “run-in” to the wellbore 160 to a desired depth adjacent to a production zone A shown in FIG. 4D . During run-in, the operator may elect to begin pumping pressurized nitrogen 180 to fill the coiled tubing 150 . Valve 67 is closed, because the inner valving ports 60 and outer valving ports 63 are totally out of alignment, and the flow blocking section 31 is blocking flow of the nitrogen 180 through outer valving ports 63 as shown in FIG. 4D . Thus, the pressurized nitrogen 180 being pumped into the coiled tubing 150 at the surface 170 is contained within the coiled tubing 150 and prevented from communicating with the surrounding formation F. As the assembly 200 is run-in, the drag blocks 52 shown in FIG. 4F are in continuous contact with the casing 165 , providing a centralizing effect as the tool 200 is lowered into the wellbore 160 .
[0040] As shown in FIGS. 4B through 4D , during run-in the bypass flow paths 12 , 69 are open, as indicated by the position of bypass ports 66 , 70 , 71 and 72 relative to the upper, middle, and lower molded seals 5 , 64 and 65 . As the wellbore fluid saver assembly 200 is run-in, a differential pressure distribution develops along the length of the tool 200 . The faster the speed of run-in, the higher the differential pressure along the tool 200 . If this pressure differential is high enough, the fluid pressure can compress or set the upper set of sealing elements 17 and the lower set of sealing elements 61 . Therefore, to equalize the pressure distribution along the tool 200 , and thereby prevent compression of the upper set of sealing elements 17 and the lower set of sealing elements 61 , wellbore fluid bypasses both sets of elements 17 , 61 . Specifically, as shown in FIGS. 4C and 4D , the wellbore fluid flows upwardly through a lower flowbore 24 in the tool 200 that is blocked at its upper end by the flow blocking section 31 in the ported mandrel 30 , and then through the bypass ports 66 into the lower bypass flow path 12 and out into the wellbore 160 through outer valving ports 63 . Simultaneously, as shown in FIGS. 4A through 4C , the wellbore fluid is routed along the upper bypass flow path 69 by flowing into ports 72 , through ports 71 , and out of ports 70 into the wellbore 160 . This bypass flow does not actuate the piston buttons 9 due to the position of the upper molded seal 5 , which prevents the piston buttons 9 from being exposed to internal pressure. The piston buttons 9 are pressure-actuated to extend outwardly and act as a locking device near the upper set of sealing elements 17 . During run-in, it is desirable to avoid locking the tool 200 in this manner.
[0041] Referring to FIGS. 4D through 4F , also during run-in, it is desirable to avoid inadvertent anchoring of the tool 200 near the lower set of sealing elements 61 . The cone 44 and the slips 45 , when engaged, anchor the tool 200 against the casing 165 . Therefore, to prevent the cone 44 from inadvertently engaging the slips 45 , a shear ring 38 and shear screw 39 shown in FIG. 4D are provided to lock the lower collet 36 to the bottom nipple 41 such that these components do not move relative to each other during run-in. The force exerted on the coiled tubing 150 during run-in is insufficient to sever the shear screw 39 . As long as the shear screw 39 engages the shear ring 38 , the cone 44 is prevented from moving relative to and sliding under the slips 45 . The shear ring 38 and shear screw 39 also prevent excessive wear on the lower collet 36 , which would otherwise bear the load carried by the shear ring 38 . Referring to FIG. 4F , the interaction between the continuous J-slot 62 and the lug 50 similarly prevents the lug assembly 68 from pushing the slips 45 upward relative to the cone 44 and engaging the cone 44 . As shown in FIG. 9 , lug 50 is located in slot 80 during run-in. This slot 80 is a shorter slot designed to prevent the lug assembly 68 from pushing the slips 45 upward relative to the cone 44 and engaging the cone 44 . Due to the position of the lug 50 within slot 80 , the lug assembly 68 is dragged along the casing 165 as the coiled tubing 150 lowers the wellbore fluid saver assembly 200 downhole.
[0042] After run-in is complete and the tool 200 has reached a desired depth adjacent to a production zone A, the operator prepares the tool 200 to set. FIGS. 5A through 5F show the tool 200 in its ready to set configuration. To move the tool 200 from the run-in configuration of FIGS. 4A through 4F to the ready to set configuration, the operator simply picks up the coiled tubing 150 , and therefore the attached tool 200 . During this lifting process, the shear screw 39 and shear ring 38 remain intact as shown in FIG. 5D , the valve 67 remains closed as shown in FIG. 5C , thus keeping nitrogen 180 contained within the coiled tubing 150 , and the bypass flow paths 12 , 69 remain open. As shown in FIG. 5F , when the tool 200 is picked up, the resistance provided by the drag blocks 52 at the casing 165 allow the coiled tubing 150 , the inner tubular system 210 , the middle tubular system 220 , and the outer tubular system 230 to travel upwards relative to the stationary lug assembly 68 until the bottom sub 56 contacts the lower end of the drag block body 54 . Simultaneously, as represented in FIG. 9 , the continuous J-slot 62 slides from an initial position at the top of slot 80 downwardly along lug 50 until the lug 50 contacts angled channel 84 of the continuous J-slot 62 , thereby causing the lug ring 49 to rotate. The rotation of the lug ring 49 shifts lug 50 downwardly into the adjacent slot 81 along the continuous J-slot 62 to prepare for the next operational step of the tool 200 , which is to set and anchor.
[0043] FIGS. 6A through 6F show the tool 200 in its set and anchored position. To move the tool 200 from the ready to set configuration of FIGS. 5A through 5F to the set and anchored position, the operator slacks off weight, meaning a downward force is applied to the coiled tubing 150 . Referring again to FIG. 9 , with the lug 50 in slot 81 at the onset of slack off, the downward force on the tool 200 causes slot 81 of the continuous J-slot 62 to slide along lug 50 until the lug 50 contacts angled channel 85 of the J-slot 62 , thereby causing the lug ring 49 to rotate and the lug 50 to shift from slot 81 to adjacent slot 82 . Referring again to FIGS. 6A through 6F , as slack off continues, the cone 44 engages the slips 45 to extend the slips 45 outwardly into engagement with the casing 165 as shown in FIG. 6F , thus anchoring the tool 200 near the lower set of sealing elements 61 .
[0044] Further slack off compresses the upper set of sealing elements 17 as shown in FIG. 6B and the lower set of sealing elements 61 as shown in FIG. 6E , severs the shear screw 39 so that it no longer engages the shear ring 38 as shown in FIGS. 6D and 6E , and causes the lower collet 36 to overcome the lower collet ring 37 as shown in FIG. 6D . Referring to FIG. 6D , the lower molded seal 65 is positioned to block the lower bypass flow path 12 such that flow is no longer permitted to bypass the lower set of sealing elements 61 by flowing through the bypass ports 66 outwardly through the outer valving ports 63 into the wellbore 160 . Also, as shown in FIG. 6B , due to the position of the upper molded seal 5 relative to bypass ports 70 in the top sleeve 4 , flow is no longer permitted to travel along the upper bypass flow path 69 to bypass the upper set of sealing elements 17 and the piston buttons 9 . As shown in FIG. 6D , the valve 67 is partially open because the inner valving ports 60 and outer valving ports 63 are partially aligned, so high pressure nitrogen 180 therefore flows from the coiled tubing 150 through the flowbore 15 and outwardly through the valve 67 . This pressure activates the piston buttons 9 , which “grip” the casing 165 , thus locking the tool 200 against the casing 165 near the upper set of sealing elements 17 as shown in FIG. 6B . Thus, in summary, FIGS. 6A through 6F show the tool 200 anchored by slips 45 and piston buttons 9 and sealed against the casing 165 by the upper set of sealing elements 17 and the lower set of sealing elements 61 , with the bypass flow paths 12 , 69 closed, and the valve 67 partially open. In this configuration, the tool 200 has isolated production zone A. An extension 90 may be required in the assembly 200 to provide the proper spacing between the upper set of sealing elements 17 and the lower set of sealing elements 61 , depending upon the length of the production zone A to be isolated.
[0045] Next, valve 67 will be fully opened and the fracturing operation performed. FIGS. 7A through 7F show the tool 200 with the valve 67 fully open as depicted in FIG. 7D , as the valve 67 would be during fracturing. To fully open the valve 67 by completely aligning the inner valving ports 60 and the outer valving ports 63 , additional set down weight is applied. The approximate amount of weight equals the amount of force required to cause the upper collet ring 26 to overcome the upper collet 28 as shown in FIG. 7C . This amount of force is applied to the coiled tubing 150 . Once the upper collet ring 26 overcomes the upper collet 28 , valve 67 is near its fully open position. Slack off continues as the operator monitors the nitrogen pressure within the coiled tubing 150 for a pressure spike that indicates valve 67 is fully open. Once that pressure spike is observed, the operator ceases to slack off. During this slacking off process, the lug assembly 68 , the middle tubular system 220 and the outer tubular system 230 of the tool 200 remain stationary while the inner tubular system 210 moves downwardly until extensions 75 on the ported mandrel 30 engage a shoulder 76 on the top sleeve 4 as shown in FIG. 7B .
[0046] With the valve 67 fully open, fracturing can take place. During fracturing, the upper set of sealing elements 17 may tend to slip downwardly, causing some loss of sealing capacity and nitrogen pressure. To prevent such slippage from occurring, the Belleville springs 21 are provided to exert an additional force on the upper set of sealing elements 17 , thereby holding them in place against the casing 165 as shown in FIG. 7B .
[0047] Once fracturing is complete, the tool 200 can be moved to the next production zone or removed from the wellbore 160 . Before moving the tool 200 , it must be unlocked. Unlike existing downhole cup-style straddle-packers where the nitrogen pressure must be vented or the formation pressure must be bled down until the cups relax, there is no such requirement to unlock the wellbore fluid saver assembly 200 . Instead, an open lower bypass flow path 12 via bypass ports 66 in the ported mandrel 30 communicating with outer valving ports 63 , and an open upper bypass flow path 69 via the bypass ports 70 , 71 , 72 , provide pressure equalization across the tool 200 while the valve 67 is closed to contain the nitrogen 180 within the tool 200 and coiled tubing 150 .
[0048] FIGS. 8A through 8F depict the tool 200 when it has been unlocked and it is being moved. To achieve this unlocked configuration, the operator simply picks up on the coiled tubing 150 and the attached tool 200 . By picking up the tool 200 , the inner tubular system 210 moves up until the extensions 75 on ported mandrel 30 engage a shoulder 77 on the top sleeve cap 3 as shown in FIG. 8A to pull the middle tubular system 220 upwardly. Thus, the load on the upper set of sealing elements 17 is removed, allowing these sealing elements 17 to relax or un-set. Continued tension on the coiled tubing 150 causes the upper collet ring 26 to travel upwards until it passes over the upper collet 28 as shown in FIG. 8B . Due to this relative movement, the inner valving ports 60 and the outer valving ports 63 are no longer aligned, thereby closing valve 67 as shown in FIG. 8C . At the same time, the lower bypass flow path 12 is opened due to the position of the bypass ports 66 in the ported mandrel 30 relative to the lower molded seal 65 . Because valve 67 is now closed, high pressure nitrogen 180 is contained within the coiled tubing 150 and the tool 200 and no longer applies a pressure load to the piston buttons 9 . Hence, the piston buttons 9 are retracted by the biasing piston spring 10 as shown in FIG. 8A . Continued tension to the coiled tubing 150 causes the lower collet 36 to pass over the lower collet ring 37 as shown in FIG. 8C , similar to what has already transpired with the upper collet 28 . The lower set of sealing elements 61 then relax or un-set as shown in FIG. 8E . Referring now to FIG. 9 , the continuous J-slot 62 slides along lug 50 as lug 50 shifts from slot 82 to slot 83 . J-slot 62 continues to travel upwards relative to lug 50 until lug 50 reaches the end of slot 83 and no further movement of J-slot 62 relative to the lug assembly 68 is permitted. Finally, as shown in FIGS. 8E and 8F , the cone 44 disengages from the slips 45 . This relative movement is possible, again, because the drag block 52 continuously engages the casing 165 to provide resistance to the tension load on the coiled tubing 150 .
[0049] The tool 200 is now ready to be moved. Valve 67 is closed, the upper set of sealing elements 17 and the lower set of sealing elements 61 are unset, the tool 200 is unanchored at both ends, and the bypass flow paths 12 , 69 are open. After the tool 200 is moved to the next frac zone, such as production zone “B” shown in FIG. 2 , for example, the entire operational sequence is repeated. Specifically, the tool 200 is moved to the ready to set configuration, if not already in this configuration, as shown in FIGS. 5A through 5F . Then the tool 200 is anchored, the upper set of sealing elements 17 and lower set of sealing elements 61 are set, and the valve 67 is partially opened, as depicted in FIGS. 6A through 6F , and so on. In this manner, multiple production zones may be fractured during a single trip downhole. Furthermore, fracturing of the wellbore 160 is completed in a minimal amount of time and with minimal waste of pressurized nitrogen 180 .
[0050] The foregoing description of the wellbore fluid saver assembly 200 which, upon completion of a wellbore service operation can be moved without venting nitrogen 180 to the surface 170 or waiting for the formation F to bleed down, has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obviously many other modifications and variations of the wellbore fluid saver assembly 200 are possible. In particular, another frac fluid could be used, instead of nitrogen. For example, frac fluids used in acidizing are compatible with this tool. Also, the sealing elements 17 , 61 may be replaced with other types of sealing devices. A different number or combination of components may be employed, and other variations are possible.
[0051] While a single embodiment of the wellbore fluid saver assembly 200 has been shown and described herein, modifications may be made by one skilled in the art without departing from the spirit and the teachings of the invention. The embodiment described is representative only, and are not intended to be limiting. Many variations, combinations, and modifications of the application disclosed herein are possible and are within the scope of the invention. Accordingly, the scope of protection is not limited by the description set out above, but is defined by the claims which follow, that scope including all equivalents of the subject matter of the claims. | A method for performing a service operation within a wellbore extending into a formation comprises sealing a first length of the wellbore to define a first isolated formation zone, flowing a pressurized fluid through a tubular string into the first isolated formation zone, and unsealing the first length of the wellbore without venting the pressurized fluid from the tubular string or awaiting depressurization of the first isolated formation zone. An assembly connected to a tubular string for performing a service operation in a wellbore comprises a mandrel with a flowbore in fluid communication with the tubular string, an upper sealing device, a lower sealing device, a selectively operable valve that enables or prevents fluid communication between the flowbore and the wellbore, and a selectively closeable bypass flow path. | 4 |
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to a fastening element for use in setting tools and having a stem provided at its opposite ends with a tip and a head, respectively, with the head being covered by a cover element.
2. Description of the Prior Art
Setting tools for driving fastening elements in a substrate include a drive piston that impacts a fastening element for driving the fastening element in. The problem with the drive piston consists in that metallic impacts of the piston on the to-be-set fastening elements, e.g., bolts or nails lead to a high wear of the piston. In setting tools having a small power, e.g., in combustion-engined setting tools, the wear of the piston tip or end is a primary reason of the piston failure. As a result, because of a rapid wear of the piston, the setting tools should be designed so as to insure an easy replacement of the drive piston. This results in high costs of the setting tools and in high maintenance costs as the drive piston should be replaced often.
U.S. Pat. No. 2,140,749 disclose a manually driven-in nail the head of which is covered with a coating. The coating remains dry at a normal room temperature. However, under higher temperatures, the coating becomes sticky. Such nails are used, e.g., in roof covering when, simultaneously with driving-in of a nail, sealing of the entry opening of the nail against the nail head should take place in order to prevent penetration of moisture. In the known fastening elements, the cover or the coating is removed, after the setting of a fastening element, only with much difficulty. However, in many applications, in which the fastening elements are driven in with a setting tool, it is required that no soft or sticky coating remains on the head of a fastening element. Accordingly, an object of the present invention is to provide a fastening element in which the above-discussed drawbacks of conventional fastening elements are eliminated and which can easily be used in a setting tool.
SUMMARY OF THE INVENTION
This and other objects of the present invention, which will become apparent hereinafter are achieved by providing a separate cover element that is detachably arranged on the head of a fastening element.
A separate cover element, which, during a setting process, absorbs the setting energy by being deformed, noticeably reduces the wear of the drive piston. Likewise, by forming the cover element as a detachable element, it is easily removed from the head after the setting process, without leaving any residue.
Advantageously, the cover element is provided with stud or a clip element for being releasably secured to the head of a fastening element. The provision of the stud or clip element insures that the cover element does not become lost during transportation, while still being easily removable from the head after the setting process.
Advantageously, the fastening elements can be assembled into a magazine by connecting separate cover elements with each other. In this case, additional elements for forming the magazine of fastening elements are not needed.
According to a further advantageous development of the present invention, the cover element is provided with a holding element that permits to releasably secure the cover element to the head of a fastening element. This holding element can be formed as a stud engageable in a groove formed in the fastening element head.
According to another advantageous development of the present invention, the holding element can be formed as a collar provided at the edge of the cover element and with which the cover element can be clipped on the head of a fastening element.
Advantageously, a strip of cover elements with the cover elements is secured not to the fastening elements but rather is provided with braces or/and webs with which the cover element strip is mounted on another magazine strip that encompasses the stems of the fastening elements. During the setting process, the webs are automatically teared off, whereby the separation of the cover element from the second magazine strip takes place automatically.
Advantageously, cover elements are formed of a plastic material, which substantially reduces the wear of the setting direction end of the drive piston. Instead of the plastic material, other deformable materials, e.g., light metals, can be used.
According to the present invention, between the cover elements of a cover element strip, there are provided weakness arears or break-off points, which insure an easy separation of the cover elements from the cover element strip during a setting process.
The novel features of the present invention, which are considered as characteristic for the invention, are set forth in the appended claims. The invention itself, however, both as to its construction and its mode of operation, together with additional advantages and objects thereof, will be best understood from the following detailed description of preferred embodiments, when read with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings show:
FIG. 1 a side view of a section of a magazine with fastening elements according to the present invention;
FIG. 2 a top view of the magazine section shown in FIG. 1;
FIG. 3 a cross-sectional view along III—III in FIG. 2;
FIG. 4 a top view on several fastening elements according to a second embodiment;
FIG. 5 a side view of a section of a magazine with fastening elements according to a third embodiment of the present invention;
FIG. 6 a top view of the magazine section shown in FIG. 5;
FIG. 7 a cross-sectional view along line VII—VII in FIG. 6 at an increased scale; and
FIG. 8 a cross-sectional view of a section of a magazine with a fastening element according to a fourth embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of a fastening element 10 according to the present invention is shown in FIGS. 1-3. The fastening element 10 has a stem 12 at one end of which, there is provide a tip 13 and at another opposite end of which, there is provided a head 11 . The head 11 of the fastening element 10 is provided with a cover element 20 that is secured to the head 11 by clip sections 35 . The cover element 20 is formed e.g., of a plastic material. A plurality of cover elements 20 are connect with each other by material webs, whereby a magazine strip 22 of fastening elements 10 is formed. The material webs form weakness areas 26 which define break-off points. In the embodiment shown in FIGS. 1-3, the stems 12 of the fastening elements 10 extend through separate segments 27 of a magazine strip 40 . The separate segments 27 are connected with each other by webs 46 having each a break-off point.
When a fastening element 10 is brought into a bolt guide of a setting tool and is advanced through the bolt guide by a setting direction end of a drive piston, a respective web 46 is teared off at its break-off point, and a respective cover element 20 is teared Doff from the strip 22 at the break-off point of the respective weakness area 26 , which insures displacement of the fastening element 10 through the bolt guide (not shown).
The clip section 35 of the cover element 20 , which is provided on the head 10 , is formed, in the embodiment shown in FIGS. 1-3, by a holding element 25 provided at an edge of the cover element 20 . The holding element 25 is formed as a concave collar. After setting of a fastening element 10 , the clip section 35 can be easily released, providing for removal of the cover element 20 from the fastening element 10 . It should be pointed out that the magazine strip 40 is not absolutely necessary as arranging the fastening elements in the magazine strip 22 suffices. However, in spite of this, it makes sense to provide separate elements on the stems which serve for guiding the fastening elements in the bolt guide of the setting tool.
The embodiment of the fastening element 10 , which is shown in FIG. 4, differs from that shown in FIGS. 1-3 in that the cover element 20 has a square shape.
In the embodiment of fastening elements 10 shown in FIGS. 5-7, the fastening elements 10 are hoisted on the magazine strip 40 which is formed, as in the embodiment of fastening element 10 shown in FIGS. 1-3, of separate segments 27 connected with each other by webs 46 . The separate segments 27 serve, as it has been discussed above, for guiding the fastening elements 10 in the bolt guide of a setting tool. However, in the embodiment of fastening elements 10 shown in FIGS. 5-7, contrary to that of FIGS. 1-3, the magazine strip 40 extends immediately beneath the heads 11 of the fastening elements 10 . Above the heads 11 , there is provided, as in the embodiment of FIGS. 1-3, a strip 22 of separate cover elements 20 which cover the heads 11 of respective fastening elements 10 . The strip 22 is connected with the located below, magazine strip 40 by web-shaped elements 23 which extends into the space between adjacent separate segments 27 . The strip 22 and the web-shaped elements 23 can be glued to the magazine strip or be welded thereto.
The strip 22 is provided with weakness areas 26 that circumscribe the cover elements 20 . When the fastening element 10 of the embodiment shown in FIGS. 5-7, is brought or advanced into the bolt guide of a setting tool and is advanced in the setting direction by the drive piston (not shown), the cover element 20 is teared off of the strip 22 at the weakness area 26 , and the separate segment 27 of the strip 40 is teared off at a web 23 . Because the cover element 20 is not connected directly with the head 11 of the fastening element, the cover element 20 falls off the head 11 immediately after the setting process, or the cover element 20 can be easily removed, without extending much force, from the head 11 of a set fastening element 10 .
In the embodiment of a fastening element 10 shown in FIG. 8, the cover element 20 is secured to the head 11 with a web-shaped element 24 with a, possibility of easy removal therefrom. The head 11 is provided, to this end, with a groove 14 into which a web-shaped holding element 24 can engage. The web-shaped holding element 24 extends from the bottom 21 of the cover element 20 . As in the previous embodiments the adjacent cover elements 20 are connected with each other by weakness areas 26 , forming the strip 22 .
It should be pointed out that the shape of a cover element should be adapted to the geometry of a head of a fastening element.
Though the present invention was shown and described with references to the preferred embodiments, such are merely illustrative of the present invention and are not to be construed as a limitation thereof and various modifications of the present invention will be apparent to those skilled in the art. It is therefore not intended that the present invention be limited to the disclosed embodiments or details thereof, and the present invention includes all variations and/or alternative embodiments within the spirit and scope of the present invention as defined by the appended claims. | A fastening element having a stem provided, at its opposite ends, with a head and a tip, respectively, and a separate cover element releasably arrangeable on the head. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 13/522,943, filed Mar. 22, 2013, which is a national stage application under 35 U.S.C. §371 of International Application No. PCT/US2011/022248, filed Jan. 24, 2011, which claims the benefit of U.S. Provisional Patent Application No. 61/297,667, filed Jan. 22, 2010, each of which is hereby incorporated by reference herein in its entirety.
[0002] This invention was made with government support under Grant Numbers N00014-08-1-0329 and N00014-08-1-0638 awarded by the Navy/Office of Naval Research. The government has certain rights to the invention.
TECHNICAL FIELD
[0003] The disclosed subject matter relates to systems, methods, and media for recording an image using an optical diffuser.
BACKGROUND
[0004] For conventional cameras, there is a fundamental trade-off between depth of field (DOF) and noise. Generally, cameras have a single focal plane, and objects that deviate from this plane are blurred due to defocus. The amount of defocus blur depends on the aperture size and the distance from the focal plane. To decrease defocus blur and increase DOF, the aperture size must be decreased, reducing the signal strength of the recorded image as well. In many cases, it is desirable to have a DOF that is as large as possible so that all details in the scene are preserved. This is the case, for instance, in machine vision applications such as object detection and recognition, where it is desirable that all objects of interest be in focus. However, stopping down the lens aperture is not always an option, especially in low light conditions, because it can increase noise, which in turn can materially impact the recorded image.
SUMMARY
[0005] Systems, methods, and media for recording an image of a scene are provided. In accordance with some embodiments, systems for recording an image of a scene are provided, comprising: a diffuser that diffuses light representing the scene and that has a scattering function that is independent of aperture coordinates; a sensor that receives diffused light representing the scene and generates data representing an image; and a hardware processor that uses a point spread function to deblur the image.
[0006] In accordance with some embodiments, methods for recording an image of a scene are provided, the methods comprising: diffusing light representing the scene using a diffuser that has a scattering function that is independent of aperture coordinates; receiving diffused light representing the scene and generating data representing an image; and using a point spread function to deblur the image
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a diagram of a mechanism for recording an image in accordance with some embodiments.
[0008] FIG. 2 is a combination of two images, one not using a diffuser (a) and one using a diffuser (b), in accordance with some embodiments.
[0009] FIG. 3 is a diagram of a lens and a sensor in accordance with some embodiments.
[0010] FIG. 4 is a diagram of a lens, a diffuser, and a sensor in accordance with some embodiments.
[0011] FIG. 5 is a diagram illustrating a light field on a sensor in accordance with some embodiments.
[0012] FIG. 6 is a diagram of a ray and the scattering of the ray in accordance with some embodiments.
[0013] FIG. 7 is a combination of point-spread-function and modulation-transfer-function graph pairs in accordance with some embodiments.
[0014] FIG. 8 is a diagram an optical system including a wedge (a) and a random varying surface in accordance with some embodiments.
[0015] FIG. 9 is combination of diagrams of a diffuser profile (a), a diffuser height map (b), a diffuser scatter PDF (c), and a diffuser (d) in accordance with some embodiments.
DETAILED DESCRIPTION
[0016] Systems, methods, and media for recording an image using an optical diffuser are provided.
[0017] Turning to FIG. 1 , an illustration of an image recording mechanism 102 (e.g., a camera, video camera, mobile phone incorporating a camera, and/or any other suitable image recording mechanism) that is being used to capture an image including three objects, A 104 , B 106 , and C 108 , is shown. As can be seen, these objects are at different depths with respect to mechanism 102 . Because of limitations in the depth of field of mechanism 102 , objects A 104 and C 108 may be out of focus when mechanism 102 is focused on object B 106 . For example, these objects may be the toys shown in FIG. 2 . As illustrated in FIG. 2( a ) , when a camera is focused on the center object (which may correspond to object B 106 of FIG. 1 ), the other objects may be out of focus. By using the mechanisms as described herein, however, an image can be recorded of such objects so that they appear to be in focus as illustrated in FIG. 2( b ) . This can be referred to as mechanism 102 having an extended depth of field.
[0018] In accordance with some embodiments, extended depth of field can be achieved by incorporating a diffuser 110 or 112 into an image recording mechanism 102 . Recording an image using a diffuser in the pupil plane of an image recording mechanism can be referred to as diffusion coding. Such a diffuser can be located at any suitable point in the image recording mechanism. For example, a diffuser 110 can be positioned between a light source (e.g., objects 104 , 106 , and 108 ) and a lens 114 (e.g., as a lens attachment), a diffuser 112 can be positioned between a lens 114 and a sensor 116 (e.g., as part of a lens or a camera body), etc.
[0019] The diffusion coding image can then be detected by sensor 116 and then provided to a hardware processor 118 (incorporated into mechanism 102 ) and/or a hardware processor 120 (external to mechanism 102 ) for subsequent processing. This processing can include deblurring the sensed image using a PSF that is matched to the PSF of the diffuser. Any other suitable processing can additionally or alternatively be used. After such processing, an extended depth of field image can be presented on a display 124 (internal to mechanism 102 ) and/or a display 122 (external to mechanism 102 ).
[0020] In order to illustrate how such an image can be recorded using a diffuser, the optics of some embodiments are now described.
[0021] As shown in FIG. 3 , a light field L(ū, x ) can be used to represent a four-dimensional set of rays propagating from an ideal lens with effective focal length (EFL) f to a sensor. A vector ū=(u,v) can be used to denote the coordinates on the u-v plane, which is coincident with the exit pupil of the lens, and a vector x =(x,y) can be used to denote the coordinates on the x-y plane that is coincident with the sensor. The irradiance E( x ) observed on the sensor can be defined as the light field integrated over all ray angles:
[0000]
E
(
x
_
)
=
∫
Ω
u
_
L
(
u
_
,
x
_
)
u
_
,
(
1
)
[0000] where, Ω ū is the domain of ū. For a scene with smooth depth variation, locally, the captured image E( x ) can be modeled as a convolution between a depth-dependent PSF kernel P( x ) and an all-in-focus image I( x ).
[0022] As described further below, in accordance with some embodiments, a camera PSF can be shaped so that an image I( x ) can be recovered from the captured image E( x ) by deblurring with a single PSF P( x ). The depth-dependence of the camera PSF can be analyzed by considering the image produced by a unit energy point source. For example, as shown in FIG. 3 , consider a point source whose image comes to focus at a distance d 0 from the aperture of the lens. Assuming a rectangular aperture of width A, the light field produced by this point can be represented as:
[0000]
L
δ
(
u
_
,
x
_
)
=
1
A
2
⊓
(
u
_
A
)
δ
(
x
_
-
s
0
u
_
)
,
(
2
)
[0000] where s 0 =(d 0 −f)/d is the defocus slope in light field space, and is the box function:
[0000]
⊓
(
x
_
w
)
=
{
1
if
x
_
i
<
1
2
,
∀
i
0
otherwise
.
(
3
)
[0000] The image of this point is the camera PSF at the depth d 0 , which is a box shaped PSF with defocus blur width s 0 A:
[0000]
P
(
x
)
=
1
s
0
2
A
2
⊓
(
x
_
s
0
A
)
.
(
4
)
[0023] The effect of a general kernel D applied to a light field L, which represents the effect of a diffuser placed in the aperture of a camera lens, can next be analyzed. The kernel can produce a new filtered light field {circumflex over (L)}, from which the modified PSF {circumflex over (P)} can be derived as:
[0000]
L
^
(
u
_
,
x
_
)
=
∫
Ω
u
_
′
∫
Ω
x
_
′
D
(
u
_
,
u
_
′
,
x
_
,
x
_
′
)
L
(
u
_
′
,
x
_
′
)
u
_
′
x
_
′
,
(
5
)
P
^
(
x
_
)
=
∫
Ω
u
L
^
(
u
_
,
x
_
)
u
_
,
(
6
)
[0000] where Ω {circumflex over (x)} is the domain of x . This approach allows a large class of operations applied to a light field to be expressed. For instance, consider a kernel of the form
[0000]
D
(
u
_
,
u
_
′
,
x
_
,
x
_
′
)
=
1
w
2
δ
(
u
_
-
u
_
′
)
⊓
(
x
_
-
x
_
′
w
)
.
(
7
)
[0024] Note that here D takes the form of a separable convolution kernel with finite support in the x domain. The geometric meaning of this kernel can be illustrated as shown in FIG. 4 . As shown, each ray in the light field is blurred so that, instead of piercing the sensor at a single location, it contributes to a square of width w. In order to understand the effect of the diffuser, an image E captured without the diffuser can be compared to an image Ê captured with it. For this diffuser kernel, substituting Equation 7 into Equations 5 and 6 gives:
[0000]
P
^
(
x
_
)
=
1
w
2
⊓
(
x
_
w
)
⊗
P
(
x
_
)
,
(
8
)
[0000] where {circle around (×)} denotes convolution. The modified PSF can be the camera PSF blurred with a box function. Therefore, the effect of the diffuser is to blur the image that would be captured were it not present. However, the diffuser given by the kernel in Equation 7 may not be useful for extending depth of field because it does not increase depth independence or preserve high frequencies in the camera PSF.
[0025] In general, the kernel for any diffuser that is placed in the aperture can be represented as:
[0000] D ( ū,ū′, x , x ′)=δ( ū−ū ′) k ( ū, x − x ′), (9)
[0000] where k is called the scatter function. As can be seen, the diffuser has no effect in the ū domain, but has the effect of a convolution in the x domain. For the diffuser given by Equation 7, the scatter function can be represented as a two-dimensional box function:
[0000]
k
(
u
_
,
x
_
)
=
1
w
2
⊓
(
x
_
w
)
.
[0026] By changing from rectangular coordinates (u,v,x,y) to polar coordinates (ρ,φ,r,θ) using the relations u=ρ cos φ, v=ρ sin φ, x=r cos θ, and y=r sin θ, a polar system where ρ,rε(—∞,∞) and θ,φε(0,π) and a circular aperture with diameter A can be considered. In this system, the light field representing a unit-energy point source located at distance d 0 can be written as:
[0000]
L
δ
(
ρ
,
r
)
=
4
π
A
2
⊓
(
ρ
A
)
δ
(
r
-
s
0
ρ
)
π
r
,
(
10
)
[0000] which is independent of both θ and φ because the source is isotropic. Note that verifying unit-energy can be carried out trivially by integrating L δ (ρ,r) in polar coordinates. Comparing the parameterizations for the light field of a point source in Equations 2 and 10, it can be seen than a slice of L δ ( x , y ) represents a single ray, while a slice L(ρ,r) represents a 2D set of rays. In the radially symmetric parameterization, a slice of the light field represents a conic surface connecting a circle with radius ρ in the aperture plane to a circle of radius r on the sensor (see FIG. 5 ).
[0027] A radially symmetric diffuser produces a drastically different effect than the diffuser given by Equation 7. When a radially symmetric diffuser is introduced, neither the diffuser nor the lens deflects rays tangentially, and therefore the diffuser kernel and modified light field can be represented using the reduced coordinates (ρ,r). Equations 5 and 6 then become:
[0000]
L
^
(
ρ
,
r
)
=
π
2
∫
Ω
ρ
∫
Ω
r
D
(
ρ
,
ρ
′
,
r
,
r
′
)
L
(
ρ
′
,
r
)
ρ
′
ρ
′
r
′
r
′
,
(
11
)
E
(
r
)
=
π
∫
Ω
ρ
L
^
(
ρ
,
r
)
ρ
ρ
,
(
12
)
[0000] and the general form of the diffuser kernel becomes:
[0000]
D
(
ρ
,
ρ
′
,
r
,
r
′
)
=
δ
(
ρ
-
ρ
′
)
π
ρ
′
k
(
r
-
r
′
,
ρ
)
π
r
(
13
)
[0028] The same box-shaped scattering function as was used for the diffuser kernel in Equation 7 can be used for Equation 13:
[0000]
k
(
r
,
ρ
)
=
1
w
⊓
(
r
w
)
.
(
14
)
[0000] However, the physical interpretation of this diffuser is different than the previous diffuser. For the previous diffuser, each ray in the light field is scattered so that it spreads across a square on the sensor. The effect of the scattering function in Equation 14, however, is as illustrated in FIG. 6 . As shown, in the absence of the diffuser, light from an annulus of width dρ and radius ρ in the aperture plane projects to an annulus of width dr and radius r on the sensor. The effect of the scatter function in Equation 14 is to spread the light incident on the sensor so that it produces an annulus of width w instead.
[0029] As illustrated by volume 602 in FIG. 6 , in polar coordinates, a ray can be a small annular section that travels from the aperture plane to the sensor plane. The effect of the diffuser, which is to scatter a ray along a radial line of width w, can be as illustrated by volume 604 .
[0030] A box-shaped scatter function can be used here for notational convenience, but a Gaussian scattering function (e.g., as illustrated in FIG. 9( c ) ) can be superior for extended DOF imaging. The light field of a point source filtered by this diffuser kernel and PSF can be shown to be:
[0000]
L
^
(
ρ
,
r
)
=
4
π
A
2
⊓
(
ρ
A
)
⊓
(
r
-
s
0
ρ
w
)
π
w
r
,
(
15
)
P
^
(
r
)
=
4
π
s
0
2
A
2
1
w
r
[
⊓
(
r
w
)
⊗
(
⊓
(
r
s
0
A
)
·
r
)
]
.
(
16
)
[0000] The analytic solution for this PSF is a piecewise function due to the contribution from the term in brackets, which is a convolution between the two rect functions (one weighted by |r|). Note that as the scattering width w is reduced to zero, the first rect (combined with 1/w) approaches a delta function and the result is a pillbox-shaped defocus PSF. Also note that if a different diffuser with different scattering function is used, the first rect is simply replaced with the new scattering function. However, the convolution term is far less significant than the 1/|r| term, whose effect dominates, resulting in a PSF which can be strongly depth independent while still maintaining a strong peak and preserving high frequencies.
[0031] As illustrated in FIG. 6 , light incident on a small annular region of width δr and radius r emanates from an annulus in the aperture, and its energy can be proportional to ρ or equivalently to r/s 0 . This explains the presence of the |r| multiplier within the term in brackets of Equation 16. This term in brackets states that the energy in a pillbox defocus PSF annulus is spread uniformly along radial lines of width w by the diffuser, as shown on the right hand side of FIG. 6 . The 1/|r| term in Equation 16 can be attributed to the fact that the energy density becomes larger for light that is scattered closer to the center of the PSF.
[0032] FIG. 7 shows several PSF 702 and Modulation Transfer Function (MTF) 704 graph pairs for a camera with ( 714 , 716 , 718 , 720 , 722 , 724 , 726 , and 728 ) and without ( 715 , 717 , 719 , 721 , 723 , 725 , 727 , and 729 ) the diffuser given by Equation 16. The defocus blur diameter s 0 A changes between 0 pixels 706 , 25 pixels 708 , 50 pixels 710 , and 100 pixels 712 . The scatter function of Equation 14 is a Gaussian instead of a box function, and the diffuser parameter w (the variance of the Gaussian) is chosen so that w=100 pixels. Note that when the diffuser is present, there is little variation with depth for either the PSF or MTF. Introducing the diffuser also eliminates the zero crossings in the MTF. For smaller defocus values, the diffuser suppresses high frequencies in the MTF. However, because the diffuser MTF does not vary significantly with depth, high frequencies can be recovered via deconvolution.
[0033] In accordance with some embodiments, diffusers of the “kinoform” type (as described in Caufield, H. J., “Kinoform Diffusers,” In SPIE Conference Series, vol. 25, p. 111, 1971, which is hereby incorporated by reference herein in its entirety) where the scattering effect is caused entirely by roughness variations across a surface can be used. Such a diffuser can be considered to be a random phase screen, and according to statistical optics, for a camera with effective focal length f, and center wavelength X, the effect of placing this screen in the aperture of the camera can result in the following:
[0000]
P
^
(
x
,
y
)
∝
p
φ
u
,
φ
v
(
x
λ
_
k
,
y
λ
_
k
)
,
(
18
)
[0000] where φ u and φ v are the u and v derivatives of the phase shift induced by the surface, and p φ x ,φ y is the joint probability of these derivatives. The result of Equation 18 is that a diffuser can be implemented by creating an optical element with thickness t(u,v), where the gradient of this surface ∇t(u,v) is sampled from a probability distribution which is also a desired PSF. Intuitively, this equation can be understood as follows: p φ u ,φ v denotes the fraction of the surface t(u,v) with slope (φ u ,φ v ). For small angles, all incoming rays incident on this fraction of the surface will be deflected at the same angle, since the slope is constant over this region. Thus, the quantity p φ u ,φ v also reflects the portion of light that will be deflected by the slope (φ x ,φ y ).
[0034] A Kinoform diffuser has a randomly varying surface with a general probability distribution of slopes as illustrated in FIG. 8( b ) . Kinoform diffusers can be thought of as generalized phase plates. For example, a regular deterministic phase plate with thickness t(u)=a λ u, as shown in FIG. 8( a ) , can also be thought of as having a slope drawn from a probability function p(φ u ) which is a delta function. The result of placing this phase plate in the pupil plane of a camera is to shift the PSF, which can be thought of as convolving p(φ u ) with the PSF.
[0035] To implement the diffuser defined in Equation 14, the diffuser surface can be implemented as a sequence of quadratic elements whose diameter and sag is drawn from a random distribution as described in Sales, T. R. M., “Structured microlens arrays for beam shaping,” Optical Engineering 42, 11, pp. 3084-3085, 2003, which is hereby incorporated by reference herein in its entirety. The scatter function of the diffuser can be designed to be roughly Gaussian with 0.5 mm variance (corresponding to w=1 mm in Equation 16) as shown in FIG. 9( c ) . To create a radially symmetric diffuser, a one-dimensional random profile can be created and then a polar transformation applied to create a two-dimensional surface (see, e.g., FIGS. 9( a ) and 9( b ) ).
[0036] In some embodiments, a diffuser can be made using laser etching.
[0037] In some embodiments, the maximum height of the diffuser surface can be 3 μm, and the diffuser can be fabricated using a laser machining technology which has a minimum spot size of about 10 μm. To ensure that each quadratic element in the diffuser is fabricated with high accuracy, the minimum diameter of a single element can be chosen to be 200 μm, resulting in a diffuser with 42 different annular sections.
[0038] Any suitable hardware can be used to implement a mechanism 102 in accordance with some embodiments. For example, a Canon EOS 450D sensor from Canon U.S.A., Inc. can be used as sensor 116 , a 22 mm diameter diffuser (e.g., as illustrated in FIG. 9( d ) ) that is laser etched in a piece of suitable optical glass by RPC Photonics of Rochester, N.Y. can be used as diffuser 110 or 112 , and a 50 mm f/1.8 lens from Canon U.S.A., Inc. can be used as lens 114 . As another example, lens 114 can have any focal length and consist of refractive optics, reflective optics, or both. For instance, a 3048 mm focal length Meade LX200 telescope (available from) can be used in some embodiments.
[0039] In accordance with some embodiments, any suitable processing can be performed to deblur the image hitting a camera sensor after passing through a lens and diffuser (in either order). For example, the Wiener deconvolution with the PSF at the center depth can be used to deblur the sensed images. Any suitable additional or alternative processing on the images can be used. For example, additional deblurring of diffusion coded images can performed using the BM3D deblurring algorithm as described in Dabov, K., Foi, A., Katkovnik, V., and Egiazarian, K., “Image restoration by sparse 3D transform-domain collaborative filtering,” In SPIE Conference Series, vol. 6812, 681207, 2008, which is hereby incorporated by reference herein in its entirety. In some embodiments, the BM3D deblurring algorithm enforces a piecewise smoothness prior that suppresses the noise amplified by the deblurring process.
[0040] Any suitable hardware processor, such as a microprocessor, digital signal processor, special purpose computer (which can include a microprocessor, digital signal processor, a controller, etc., memory, communication interfaces, display controllers, input devices, etc.), general purpose computer suitably programmed (which can include a microprocessor, digital signal processor, a controller, etc., memory, communication interfaces, display controllers, input devices, etc.), server, programmable gate array, etc. can be used to deblur the image captured by the sensor. Any suitable hardware can by used to transfer the image from the sensor to the processor. Any suitable display, storage device, or printer can then be used to display, store, or print the deblurred image.
[0041] In some embodiments, any suitable computer readable media can be used for storing instructions for performing the processes described herein. For example, in some embodiments, computer readable media can be transitory or non-transitory. For example, non-transitory computer readable media can include media such as magnetic media (such as hard disks, floppy disks, etc.), optical media (such as compact discs, digital video discs, Blu-ray discs, etc.), semiconductor media (such as flash memory, electrically programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), etc.), any suitable media that is not fleeting or devoid of any semblance of permanence during transmission, and/or any suitable tangible media. As another example, transitory computer readable media can include signals on networks, in wires, conductors, optical fibers, circuits, any suitable media that is fleeting and devoid of any semblance of permanence during transmission, and/or any suitable intangible media.
[0042] Although the invention has been described and illustrated in the foregoing illustrative embodiments, it is understood that the present disclosure has been made only by way of example, and that numerous changes in the details of implementation of the invention can be made without departing from the spirit and scope of the invention, which is only limited by the claims which follow. Features of the disclosed embodiments can be combined and rearranged in various ways. | Systems, methods, and media for recording an image of a scene are provided. In accordance with some embodiments, systems for recording an image of a scene are provided, comprising: a diffuser that diffuses light representing the scene and that has a scattering function that is independent of aperture coordinates; a sensor that receives diffused light representing the scene and generates data representing an image; and a hardware processor that uses a point spread function to deblur the image. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to improvements in pulp washers and, more particularly, to an improved method and mechanism for washing cellulose pulp fibers.
When wood is chemically processed to obtain cellulose pulp fibers for papermaking, the process includes cooking or digesting wood chips with various pulping liquors so that the resins and materials binding the cellulose fibers together are dissolved in the pulping liquor, thereby liberating the fibers. The result is a slurry of fibers suspended in a liquid of water and spent chemicals or liquor. To further prepare the pulp for papermaking, the fibers must be separated from the liquid, the liquid removed and the fibers washed to remove what chemicals remain with the fiber.
PRIOR ART
The goal of pulp washing is to separate soluable impurities from the pulp fiber, to obtain pulp essentially free from impurities. An optimum pulp washing system would remove waste liquor and other impurities completely, while using only a minimal amount of wash liquid. For chemical recovery and/or other subsequent waste liquor processing, any wash fluids added during the washing stage must also be treated, either by evaporation or by other means. Therefore, it is desirable to minimize the amount of wash fluid added during the washing process, to minimize dilution of the pulping liquors and the subsequent cost of reprocessing the chemicals in subsequent treatment stages.
In evaluating the efficiency of washing systems, the papermaking industry has adopted the term "dilution factor" to define the amount of wash fluid used. The dilution factor can be described as the amount of water or other wash liquid put into the system and not taken out of the system with the washed pulp as the pulp is removed from the system. If the quantity of wash fluid added is equal to the quantity of wash fluid passing from the system with the pulp, the dilution factor is zero. Low dilution factors are, therefore, most desirable.
Methods used heretofore for the washing of cellulose stock are discussed below:
DILUTION--AGITATION--EXTRACTION (EXTRACTION WASHING)
In this washing process, excess liquor is drained from the pulp, and the pulp is diluted with water and/or weaker liquor from a following stage. The mixture is thoroughly agitated to promote equilibrium. The mixture is then again dewatered to a predetermined extent. The process efficiency is related to the degree of equilibrium reached in the agitation cycle, and the degree of extraction between successive dilution stages. Compaction may be used to enhance the extraction stage. The removal of solids and weak black liquor concentrations in extraction washing is dependent on the inlet and discharge consistencies of the pulp for a given dilution factor.
Extraction washing systems usually require a plurality of extraction stages to accomplish acceptable washing results, and have inherently high dilution factors. Present day chemical recovery practices and environmental standards have reduced the acceptance of this washing technique.
DISPLACEMENT WASHING
In this method, the liquor within the slurry void spaces is displaced with wash water and/or filtrate from following stages. Diffusion of the wash liquid through the pulp is controlled to avoid mixing. The process efficiency is related to the degree of mixing and channelling that occurs during displacement, which decreases efficiency, and the degree of equilibrium reached between pulp fibers and liquor pockets and wash liquor.
Methods for performing displacement washing have included forming a mat of the stock on the top surface of a rotating perforated drum or a traveling belt and spraying the displacement liquid onto the top of the mat. The liquid passing through the belt is removed from beneath the belt. A substantial disadvantage in this type of arrangement has been the creation of foam and froth on the top of the wire, which has to be removed and handled. Further, protective hoods or canopies have to be provided to handle the spray.
DILUTION--EXTRACTION--DISPLACEMENT
This method utilizes combined operations of the previous two methods, and its efficiency is dependent on the variables affecting the operation of each. Approximately 85% of the Kraft pulp mills today use this method for pulp washing. The pulp is diluted with the liquor from the following stage, and is agitated to promote equilibrium. Extraction occurs, followed by the displacement of the liquor remaining in the pores. Drum washers, either pressurized or under vacuum, have been used to perform this washing method. As with the earlier described methods, with respect to the washing surface, the pulp fibers are more or less in a static state as the extraction and displacement occur.
Some of the difficulties with this method include the negative effects of entrained air in the pulp and, in the case of vacuum washers, the limitations on washing temperature. Generally, drainage of liquor through a pulp mat improves with elevated temperatures, and higher temperatures therefore improve washing efficiency. However, vacuum washers, which operate with up to -5 psi in the drum, create lower equilibrium temperature conditions. Therefore, it is not possible to significantly raise the operating temperature of vacuum washers to further improve the drainage characteristics of the pulp.
Pressure washers operating similarly to vacuum washers, but with a positive pressure in a hood above the pulp mat, have overcome, to some degree, the temperature limitations of vacuum washers. However, as with vacuum washers, the stock surface is exposed to air, and the ability to control the washing process by the stock pressure is lost. Further, air entrainment in the stock is significant, and foam resulting from the entrained air, at times, is difficult to control. Air in the pulp reduces the efficiency of subsequent wash stages, further increasing the washing capacity required to reach the desired degree of washing. Defoaming agents are helpful, but add cost and present additional handling and disposal problems.
Previously known washing techniques employing extraction or displacement have maintained relatively static relationships between the fibers being washed and the retention surface through which the separation occurs. Typically, today, this includes the formation of a mat on a wire, drum or the like. As the liquid is removed, the mat is stationary with respect to the drum or wire. The resulting relatively slow extraction or displacement requires equipment to be large for adequate capacity. Therefore, capital expense for equipment and space requirements are large.
OBJECTS OF THE PRESENT INVENTION
An object of the present invention is to provide a continuously operating mechanism and method for the washing of cellulose stock which avoids disadvantages of methods and structures heretofore available, and which is capable of performing a washing operation without the generation of froth and foam.
A further object of the present invention is to provide an improved stock washing mechanism and method which improves the quality of the stock being washed, and which utilizes the carrier liquid in the stock for washing and subjects the fibers to a continuous reslushing and rewashing process with agitation while addition of fresh wash liquid is minimized, resulting in a minimum dilution of the liquor.
A still further object of the present invention is to provide a stock washer which has an improved arrangement for handling the liquors and liquid and an improved arrangement for removing the stock fibers.
Another object of the present invention is to provide a stock washer operating under a pressurized atmosphere to handle high temperature stock and also to improve the washing operation efficiency.
Yet another object of the present invention is to provide a stock washing apparatus which keeps the stock under high turbulence at high consistency for improved washing operation efficiency.
Still another object of this invention is to provide a stock washing apparatus and method which reduce the area required for washing equipment and which achieve economy of piping and pumping, and decreased capital investment for washing equipment in comparison with existing washing techniques for a given degree of washing.
SUMMARY OF THE INVENTION
The present invention provides a method and apparatus for washing pulp stock in an enclosed atmosphere under pressurized conditions wherein the stock is driven along a stationary barrier or washer wire by the pressure differentials between the stock inlet and stock outlet of the washer. Fresh wash liquid is admitted at the stock outlet end and flows counter current to the stock which is repeatedly formed, agitated, diluted and washed as it moves along the stationary barrier. Filtrate is driven by the pressure differentials across the barrier, which restricts the passage of fiber therethrough. A rotor generates high frequency, low amplitude pulses in the stock as the stock passes along the wire and creates localized mixing, reslurrying and washing of the fiber.
Other objects, advantages and features of the invention, as well as alternative embodiments of the structures and methods, will become more apparent with the description of the principles of the invention in connection with the disclosure of the preferred embodiments in the specification, claims, and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical sectional schematic representation which shows a generic stock washing mechanism constructed and operating in accordance with the principles of the present invention.
FIG. 2 is a vertical cross-sectional view taken through a preferred embodiment of a dynamic pulp washer which operates in accordance with the principles of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now more specifically to the drawings, and to FIG. 1 in particular, the pressurized dynamic washer of the present invention includes a body (1) and a rotor assembly (2) axially disposed in the body. The main shell or body (1) is divided into three major zones. The first is an inlet zone (3) located at the front of the washer, generally at the end of the rotor. An inlet pipe (4) enters the inlet zone in a tangential manner at the top of the shell, to supply stock to the washer under velocity tangential to the washer axis.
The second zone within the body (1) is a washing zone (5), which may be separated into several subzones at the outer shell area for the extraction of wash liquors. A cylindrical washer wire or barrier (6) is disposed along the washing zone, isolating a filtrate pipe (7), located at the top of the shell, from the rotor assembly (2) axially disposed within the washer and wash wire. Thus, only the wash liquor passing through the wash wire will reach the filtrate pipe. The wash wire forms a barrier along which separation of the fiber from the liquor occurs.
The third zone of the body is an outlet zone (8), located at the rear of the washer, at an opposite end of the rotor and wire from the inlet zone, and is the area where the washed stock is discharged from the washer.
The washing zone of the washer is shown to have two compartments, (9) and (10), behind the wash wire. These compartments are separated from each other by a baffle (11). The wash water is introduced at the rear side of the washer through a pipe (12). The quantity of fresh water added is controlled by a control valve (18). The liquor in the stock is displaced by the fresh water and is extracted through the wash wire into compartment (10). The stock, after washing, is discharged from the washer through stock line (19). The filtrate from compartment (10) is introduced at the inlet side of the washer through a pipe (13) without the aid of a pump, purely on the basis of pressure differentials. The pressure at the central zone of the washer is lower than the pressure at the discharge point of the filtrate from compartment (10). It will be recognized, however, that pumps can be used.
The filtrate introduced at the inlet side of the washer through the pipe (13) is used for internal dilution. Since the filtrate has a lower solute concentration than the liquor already present in the stock as the filtrate displaces the higher solute concentrated liquor in this zone, which is transported to compartment (9) through the wash wire, the stock fiber is freed from a quantity of soluable impurities. The higher concentrated liquor in compartment (9) is discharged from the washer through filtrate pipe (7).
The flow through inlet pipe (4), high concentration filtrate line (7), filtrate recirculation pipe (13), washed stock outlet line (19) and fresh water pipe (12) are controlled by valves (14), (15), (16), (17), and (18) respectively, to maintain steady state operation of the washer by creating pressure differentials across the wire, between inner and outer areas and also across the washer between the stock inlet and washed stock outlet.
With reference now to FIG. 2, a more specific description will be made of a preferred embodiment for the pressurized dynamic washer disclosed with respect to the schematic of FIG. 1. In FIG. 2, numeral 100 designates a pressurized dynamic washer constructed to operate in accordance with the principles of the present invention. A fabricated body (110) of, preferably, stainless steel or the like, includes an outer substantially cylindrical shell (112) having a flange (114) for receiving a cover (116) at the inlet end of the washer. The body (110) further includes a substantially conically-shaped portion (118) at the outlet end of the washer.
A rotor assembly (120) is generally disposed along the axis of the body (110), and includes a rotor shaft (122) drivingly attached to a motor (124) and connected to a rotor body (126) having a plurality of knobs or bumps (128) on the outer surface thereof. The rotor, thus far described, is frequently referred to as a fractionating type rotor, which generates high frequency, low amplitude pulses in the stock. The bumps (128) may be hemispherical or of other shape.
An inlet zone (130) is defined generally by the cover (116), a portion of the shell (120), an internal shell flange (132) and an end (136) of the rotor body (126). An inlet pipe (140) provides a slurry of the stock to be washed to the inlet zone (130). The orientation of inlet pipe (140) with respect to the rotor, rotor axis and inlet zone is such as to provide significant tangential velocity to the stock.
An internal wall (142) of the shell (112) supports the rotor assembly (120) on bearings (144) receiving the rotor shaft (122). Wall (142) includes a flange (146). The flange (132) at one end of the washer, and the flange (146) at the other end of the washer define, generally, the inlet and outlet extreme locations of a washing zone (150) which receives stock from the inlet zone (130).
A wash wire (160) is connected to the flanges (132) and (144) by wash wire mounting flanges (162) and (164), respectively. The washing wire (160) is a cylindrical, perforate basket, preferably smooth, and having holes or slots sufficiently small to limit the passage of cellulose fibers under the pulses from the rotor assembly (120). Slots measuring 0.006 inch in a smooth basket design have been found to work well; however, slots within the range of from about 0.002 inch to about 0.012 inch and holes within the range from about 0.004 inch to about 0.012 inch are suitable.
Wash wire (160) forms a stationary barrier along which the stock flows from the inlet end of the washer to the outlet end. The washer wire is closely spaced from the rotor body (126) with its bumps (128) thereon, and separates the washing zone (150) into radially inner and radially outer portions. Stock from the inlet zone (130) enters the radially inner portion of the washing zone through a space (166) between the rotor and the inner surface of the wash wire. Liquids displaced from the stock flow through the slots in the wire to the radially outer portion of the washing zone (150). Some or all of the displaced liquids can be conducted from the washer through a filtrate outlet (170), while washed stock is conducted from the washer through a washed stock outlet (180).
The radially outer portion of the washing zone (150) is divided into subzones (190) and (200) by a baffle (210). It should be recognized that two or more baffles such as baffle (210) may be used to provide three or more washing subzones similar to subzones (190) and (200).
Stock which enters the space (162) between the outer surface of the rotor assembly (120) and the inner surface of the wash wire (160) flows along the wash wire due to maintained pressure differential between inlet and outlet pressures. A wash liquid line (220) is provided in the wall (142) and supplies wash liquid which displaces the liquor in the stock, which liquor is extracted through the wash wire into the subzones (190) and (200). A filtrate recirculation line (230) conducts filtrate from subzone (200) to a filtrate recirculation inlet (232) in the cover (116).
The fibers to be washed are fed in the form of a stock slurry by supply means not shown to the inlet pipe (140), with the stock being discharged tangentially to the washer at the inlet zone (130). A stock slurry of liquor and fiber of about 0.2 to 4.5% consistency, and preferably from 3.0 to 3.5% consistency, at temperatures up to 200° F. is fed to the washer.
The fiber slurry enters the washing zone (150) through the space (162). The fibers are forced to move along the wash zone 150 is a path substantially parallel to washer wire (160). It is difficult for fibers to pass through the wire because of the approach angle of a fiber to a slot. The fibers travel in the axial direction from the inlet zone (130) to the washed stock outlet (180) of the washer.
There are three primary velocities acting inside the washer to aid the mechanism of washing. These components are the axial, radial and tangential velocities. The axial velocity is along the axis of rotation of the washer and generally parallel to the wash surface of the wash wire. This velocity is controlled by the pressure differential between the stock inlet and the washed stock outlet. This axial velocity is affected by the size of annulus between the wash wire and the body of the rotor, and on the volume of flow towards the stock outlet.
The radial velocity is toward and through the washer wire. This velocity is controlled by the pressure differential between the stock inlet and the wash filtrate outlet. The radial velocity depends upon the total area of the washer wire, the open area in the wire and on the volume of filtrate flow.
The tangential velocity is the rotational velocity of the stock about the axis of the washer. The tangential velocity depends to a large extent upon rotor design.
The velocities in the washer produce radial drag forces, shear forces and turbulent forces which together mix, reslurry and dewater the stock to achieve the desired degree of washing efficiency in the washing zone.
Because of the transverse velocity, which is a combination of the velocities created in the washer, the effective size of wire opening as presented to fibers flowing through the washer is reduced. This reduction of apparent wire opening is an important mechanism for the efficient separation of liquid from the stock. The differential pressure created between the interior of the washer and the filtrate chamber drives the liquid through the washer wire. However, the fibers, being influenced by the transverse velocity, will not pass through wire openings which would allow fiber passage if the fibers were influenced only by radial velocity. The stock inside the washer reaches higher consistency than the inlet consistency due to the extraction of liquid.
The stock in the washing zone is exposed to several washing mechanisms, including dilution, mixing, extraction and displacement. The process efficiency depends upon the degree of equilibrium reached in mixing and the degree of extraction and displacement achieved under a particular operation condition of the washer. High degree of mixing is achieved in this washer due to the operation of a high speed rotor in close proximity with the wash wire. This quickly produces a uniform concentration of solute at any point of the washer, when a high solute concentrated liquor in the stock is mixed with a low solute concentrated liquor or fresh water. This liquor, after achieving equilibrium concentration, is extracted through the wire.
Although the device described here consists of two stages of washing, it is obvious to one skilled in the art that this may be extended to incorporate any number of stages within a single system.
The present dynamic washer generates a turbulent, fluidized displacement as compared tot he static displacements known previously. Displacement is more efficient and the present washer may be about one-third the physical size of a comparable drum washer.
Thus, it can be clearly seen from the description provided that an improved washer and washing method, which provide the objectives and features above set forth, are provided. It should be recognized, however, that various changes may be made without departing from the scope of the present invention. | A pressurized dynamic pulp washer in which stock is driven along a stationary wash wire and pulses are generated in the stock to urge liquid through openings in the wash wire. Wash liquid is introduced countercurrent to the flow of stock, and localized mixing and reslurrying occurs. | 3 |
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to vehicle seating and more particularly to a locking apparatus for a moveable component of an aircraft seat.
[0002] Seating units, particularly those in aircraft, are often provided with one or more components which are moveable so that a passenger seated therein can be comfortably supported in various positions. For example, the bottom of the seat may be translatable fore and aft. In order to provide the desired crash-worthiness, these moveable components must be securely locked in position when not actually being moved by the passenger. They must also be easy and convenient for the passenger to move when necessary, and they must withstand repeated and sometimes rough usage. Various prior art seats include electric motors or actuators to operate the moveable components, or pneumatic or hydraulic elements such as “hydrolocks”. While these type of devices provide the desired adjustability, they are relatively complex and expensive compared to purely mechanical arrangements.
BRIEF SUMMARY OF THE INVENTION
[0003] Therefore, it is an object of the invention to provide a locking apparatus for a moveable portion of a passenger seat which allows the seat to be selectively locked in a desired position.
[0004] It is another object of the invention to provide a locking apparatus that has an infinite number of locking positions.
[0005] It is another object of the invention to provide a locking apparatus that is mechanical in operation.
[0006] It is another object of the invention to provide a locking apparatus that is inexpensive to manufacture.
[0007] These and other objects of the present invention are achieved in the preferred embodiments disclosed below by providing a locking apparatus including a housing for being slidably received in a track; a first pair of opposed cams pivotally mounted in the housing, the cams being moveable between a lock position and a release position, wherein the cams prevent the housing from sliding within the track when in the lock position; and a release member selectively positionable from a first position where the cams are maintained in the lock position and a second position where the cams are maintained in the release position.
[0008] According to another preferred embodiment of the invention, the locking apparatus further includes a second pair of opposed cams pivotally mounted in the housing.
[0009] According to another preferred embodiment of the invention, the first pair of opposed cams and the second pair of opposed cams have offset pivot points for creating a progressive lobe for each respective cam.
[0010] According to another preferred embodiment of the invention, the first pair of opposed cams and the second pair of opposed cams are connected by a spring.
[0011] According to another preferred embodiment of the invention, the release member has an end having a length greater than its width.
[0012] According to another preferred embodiment of the invention, the first pair of opposed cams have offset pivot points for creating a progressive lobe for each respective cam.
[0013] According to another preferred embodiment of the invention, at least one roller is carried by the housing for permitting the housing to slide within the track.
[0014] According to another preferred embodiment of the invention, the first pair of opposed cams are mounted in a recess of the housing.
[0015] According to another preferred embodiment of the invention, the first pair of cams protrude from the housing when in the lock position to engage and prevent the housing from sliding within the track.
[0016] According to another preferred embodiment of the invention, a reclining seat includes a track fixedly attached to a frame; a seat pan assembly mounted for sliding movement within the track; and a locking apparatus fixedly attached to the seat pan assembly. The locking apparatus includes a housing for being slidably received in the track; a first pair of opposed cams pivotally mounted in the housing, the cams being moveable between a lock position and a release position, wherein the cams prevent the housing from sliding within the track when in the lock position; and a release member selectively moveable from a first position where the cams are maintained in the lock position and a second position where the cams are maintained in the release position.
[0017] According to another preferred embodiment of the invention, the seat pan assembly includes a pair of spaced-apart, longitudinally-extending rails connected by a plurality of cross-members.
[0018] According to another preferred embodiment of the invention, the locking apparatus is positioned on an outside surface of each of the respective rails at a rear end of each rail.
[0019] According to another preferred embodiment of the invention, each of the rails includes a roller for being received in a track.
[0020] According to another preferred embodiment of the invention, the reclining seat further includes a seat back pivotally mounted to the seat pan assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The subject matter that is regarded as the invention may be best understood by reference to the following description taken in conjunction with the accompanying drawing figures in which:
[0022] FIG. 1 is a perspective view of a passenger seat including a moveable seat pan assembly;
[0023] FIG. 2 is an exploded view of the seat pan assembly of FIG. 1 ;
[0024] FIG. 3 is a perspective view of a locking apparatus attached to a seat pan assembly and positioned within a track;
[0025] FIG. 4 is a plan view of an exemplary locking apparatus disposed within a track in a locked position;
[0026] FIG. 5 is a plan view of the locking apparatus of FIG. 4 in a released position;
[0027] FIG. 6 is an end view of the locking apparatus of FIG. 4 ;
[0028] FIG. 7 is a plan view of an alternative locking apparatus disposed within a track in a locked position; and
[0029] FIG. 8 is a plan view of the locking apparatus of FIG. 7 .
DETAILED DESCRIPTION OF THE INVENTION
[0030] Referring now specifically to the drawings, an exemplary passenger seat constructed according to an embodiment of the present invention is illustrated in FIGS. 1-3 and shown generally at reference numeral 10 . The seat 10 has a seat frame 11 for being attached to the deck of an aircraft (a portion of which is shown in FIG. 2 ) and includes a seat pan assembly 12 slidably attached to the seat frame 11 , a seat bottom 13 , a seat back 14 pivotally attached to a pair of pivots 15 A and 15 B of the seat pan assembly 12 , and a headrest 16 . The seat frame 11 includes two spaced-apart, longitudinal, inward-facing C-shaped tracks 17 and 18 connected by a plate 19 . The seat pan assembly 12 includes a seat pan 20 attached to a seat pan frame assembly 21 which includes a pair of spaced-apart rails 22 and 23 connected by a plurality of cross-members 24 . Rollers 26 and 26 ′ and a locking apparatuses 27 and 27 ′ are positioned on an outside surface of the rails 22 and 23 respectively, and are sized to fit in the C-shaped tracks 17 and 18 , as shown in FIG. 3 , to allow the seat pan assembly 12 to slide therein. In the illustrated example, the rollers 26 and 26 ′ are positioned approximately midway between a first end 28 and a second end 29 of the respective rails 22 and 23 and the locking apparatuses 27 and 27 ′ are positioned at the second end 29 of each rail 22 and 23 .
[0031] The locking apparatuses 27 and 27 ′ are substantially identical in construction, therefore, only the locking apparatus 27 will be described in detail. As illustrated in FIGS. 4-6 , the locking apparatus 27 includes two pairs of opposing cams positioned within a recess 30 of a housing 31 , each pair having an inner cam 32 A, 33 A and an outer cam 32 B, 33 B pivotally attached to the housing 31 . The pivot point for each cam 32 A, 32 B, 33 A, and 33 B is offset to create a progressive lobe 34 for each cam which increases pressure on the tracks 17 and 18 when sliding loads are applied. The outer cams 32 B and 33 B are connected by a spring 36 or other suitable structure which pulls the outer cams 32 B and 33 B towards the inner cams 32 A and 33 A, engaging and forcing the inner cams 32 A and 33 A against a release member 37 located in the center of the housing 31 . The release member 37 includes a non-circular end 38 having a length greater than its width. As illustrated, the end 38 is rectangular. In the illustrated example, a roller 39 is positioned within a recess 40 located at each corner of the housing 31 and extends slightly past an outside edge of the housing 31 , allowing the locking apparatus 27 to slide easily within the track 17 .
[0032] In the locked position, the cams 32 A, 32 B, 33 A, and 33 B engage an inside surface of the track 17 to prevent the locking apparatus 27 from sliding, thereby preventing the seat pan assembly 12 from translating fore or aft with respect to the frame 11 . The cams 32 A, 32 B, 33 A, and 33 B are placed into a locked position by turning the release member 37 so that the end 38 is generally perpendicular to the track 17 . The spring 36 forces the cams 32 A, 32 B, 33 A, and 33 B to pivot towards the center of the housing 31 by pulling the outer cams 32 B and 33 B towards each other, forcing the outer cams 32 B and 33 B to engage the inner cams 32 A and 33 A, thereby moving the lobes 34 past the outside edge of the housing 31 and against the inside surface of the track 17 . As shown, cams 32 A and 32 B prevent movement in the forward direction and cams 33 A and 33 B prevent movement in the aft direction.
[0033] To release the locking apparatus 27 , the release member 37 is turned so that the end 38 is generally parallel with the track 17 . The release member 37 forces the inner cams 32 A and 33 A against the outer cams 32 B and 33 B, forcing both pairs of cams 32 A, 32 B and 33 A, 33 B away from the center of the housing 31 against the spring 36 , and thereby disengaging the cams 32 A, 32 B, 33 A, and 33 B from the inner surface of the track 17 and allowing the seat pan assembly 12 to translate freely between fore and aft positions.
[0034] The cams 32 A, 32 B, 33 A, and 33 B may also be turned around so that the progressive lobes 34 face inward towards the center of the housing 31 , allowing the lobes to bear against a rod, bar, tube or other member passing through the center of the locking apparatus 27 .
[0035] In operation, the seat 10 is reclined by turning the release member 37 to the release position as described above, allowing the seat pan assembly 12 to translate fore and aft with respect to the seat frame 11 . Any means which allows the passenger to turn the release member 37 may be used. For example, a cable may be attached between a passenger-operable lever or button and the release member 37 , or a button may be positioned on an armrest and operably connected to a motor or hydraulic actuator for turning the release member 37 .
[0036] The fore and aft movement of the seat pan assembly 12 causes the seat back 14 to move between an upright and recline position. Once a desired recline position has been determined, the seat 10 is locked in position by turning the release member 37 , as discussed above, to the lock position, allowing the cams 32 A, 32 B, 33 A, 33 B to engage the track 17 . Unlike prior art devices that use notches or slots, the locking apparatus 27 allows for infinite adjustment, since the cams 32 A, 32 B, 33 A, and 33 B are designed to engage a flat surface and do not require dimples, notches, slots, or any other type of depression to lock the seat pan assembly 12 in position.
[0037] Referring now to FIGS. 7 and 8 , in an alternate embodiment of the invention, a locking apparatus 127 includes one pair of opposing cams positioned within a recess 130 of a housing 131 , the pair having an inner cam 132 A and an outer cam 132 B pivotally attached to the housing 131 . The pivot point for each cam 132 A and 132 B is offset to create a progressive lobe 134 for each cam. The outer cam 132 B is connected to a post 141 by a spring 136 or other suitable structure which pulls the outer cam 132 B towards the inner cam 132 A, forcing the inner cam 132 A against a release member 137 located in the center of the housing 131 . The release member 137 includes a non-circular end 138 having a length greater than its width. As illustrated, the end 138 is rectangular. In the illustrated example, a roller 139 is positioned within a recess 140 located at each of the two aft corners of the housing 131 and extends slightly past an outside edge of the housing 131 , allowing the locking apparatus 127 to slide easily within the track 17 .
[0038] In the locked position, the locking apparatus 127 only prevents the seat pan assembly from translating in the fore direction, allowing the seat pan assembly to freely move in the aft direction. In this embodiment, the cams 132 A and 132 B engage an inside surface of the track 17 to prevent the locking apparatus 127 from sliding, thereby preventing the seat pan assembly 12 from moving fore with respect to the frame 11 . The cams 132 A and 132 B are forced into a locked position by turning the release member 137 so that the end 138 is generally perpendicular to the track 17 . The spring 136 forces the cams 132 A and 132 B to pivot towards the center of the housing 131 by pulling the outer cam 132 B towards the center of the housing 131 , forcing the outer cam 132 B to engage the inner cam 132 A, thereby forcing the lobes 134 past the outside edge of the housing 131 and against the inside surface of the track 17 .
[0039] To release the locking apparatus 27 , the release member 137 is turned so that the end 138 is generally parallel with the track 17 . The release member 137 forces the inner cam 132 A against the outer cam 132 B, forcing the cams 132 A and 132 B away from the center of the housing 131 against the spring 36 , and thereby disengaging the cams 132 A and 132 B from the inner surface of the track 17 .
[0040] The foregoing has described a locking apparatus for a vehicle seat. While specific embodiments of the present invention have been described, it will be apparent to those skilled in the art that various modifications thereto can be made without departing from the spirit and scope of the invention. Accordingly, the foregoing description of the preferred embodiment of the invention and the best mode for practicing the invention are provided for the purpose of illustration only and not for the purpose of limitation, the invention being defined by the claims. | A locking apparatus for a moveable component of an aircraft seat. The locking apparatus includes a housing for being slidably received in a track, a first pair of opposed cams pivotally mounted in the housing, and a release member. The cams are moved between a lock position where the cams prevent the housing from sliding within the track and a release position. The release member is selectively moveable between a first position where the cams are maintained in the lock position and a second position where the cams are maintained in the release position. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to U.S. patent application Ser. No. 12/616,762 entitled “Implantable Vertebral Frame Systems and Related Methods for Spinal Repair”, filed Nov. 11, 2009, which is a continuation-in-part of U.S. patent application Ser. No. 11/855,124 entitled “Implantable Bone Plate System and Related Method for Spinal Repair”, filed Sep. 13, 2007, which claims priority to U.S. Provisional Patent Application Ser. No. 60/954,511 entitled “Implantable Bone Plate System and Related Method for Spinal Repair”, filed Aug. 7, 2007. Each patent application is incorporated herein by reference in its entirety.
[0002] The present invention relates to a system for performing surgical repair of the spine, such as for but not limited to the delivery of an interbody repair device for the purpose of either fusion or dynamic stabilization.
BACKGROUND
[0003] It is current practice in spinal surgery to use bone fixation devices to improve the mechanical stability of the spinal column and to promote the proper healing of injured, damaged or diseased spinal structures. Typically, corrective surgery entails the removal of damaged or diseased tissue, a decompression of one or more neural elements, followed by the insertion of an intervertebral implant for the purposes of a fusion or disc arthroplasty. In cases where spinal fusion is the desired surgical outcome, the final step is often to apply a bone plate in order to immobilize adjacent vertebral bones to expedite osteogenesis across said vertebral segments.
[0004] Most current surgical techniques require that damaged vertebral tissue be placed under rigid axial distraction throughout much of the procedure. This allows for greater ease in the removal of tissue, provides a larger working space for instrument maneuverability, enhances the surgeon's visibility and assists with the fit of the interbody implant once the distractor apparatus is removed. Conventional distraction of the spine typically employs the use of temporary “distractor pins” placed directly into the bone tissue adjacent to the disc space to be repaired, which are subsequently induced to move axially by the attachment and adjustment of a secondary tool. An alternative method employs the use of a ratcheting spreader device which is inserted directly into the vertebral interspace and is adjusted thereafter to achieve desired distraction.
[0005] In the conventional method, once the implant has been inserted, the distractor device is removed and the vertebrae can be secured by the attachment of a bone plate. Such bone plates, including a plurality of bone screws, are applied near the completion of the procedure to provide vertebral fixation and prohibit undesirable migration of the intervertebral implant.
[0006] Several design constructs have already been proposed in which a device is applied to adjacent vertebrae at the start of a procedure, prior to tissue removal, for the purposes of achieving and maintaining preferred vertebral alignment while serving also to constrain tissue removal throughout the procedure. The disclosed or published art in this method can generally be categorized into two broad categories: removable devices and permanently implantable devices.
[0007] The removable devices differ from the present proposed invention in that the devices used to maintain preferred vertebral alignment are temporary inserts and are subsequently removed after tissue removal so that a repair device may be delivered thereafter. The prior art which discloses permanently implantable devices differs in that the devices function solely to maintain preferred vertebral alignment and are not part of a comprehensive system and related method to precisely control and permanently maintain the preferred spatial relationship of adjacent vertebral members for controlled tissue removal and delivery of a repair device.
Removable Devices
[0008] U.S. Pat. No. 7,153,304 entitled Instrument System for Preparing a Disc Space Between Adjacent Vertebral Bodies to Receive a Repair Device, issued Dec. 26, 2006 to Robie et al., discloses a removable instrument system for preparing a disc space between adjacent vertebral bodies using a series of distractors that restore natural lordosis before a temporary template is attached for vertebral immobilization and to function as a guide for an insertable reamer meant for tissue removal.
[0009] U.S. Pat. No. 7,083,623 to Michelson, entitled Milling Instrumentation and Method for Preparing a Space Between Adjacent Vertebral Bodies, issued Aug. 1, 2006, discloses a removable milling device and method for preparing a space between adjacent vertebral bodies which essentially maintains preferred vertebral alignment while functioning as a saw guide to control bone and soft tissue removal.
[0010] US Pat. App. 2005/0043740 to Haid, entitled Technique and Instrumentation for Preparation of Vertebral Members, published Feb. 24, 2005, discloses a removable instrumentation set and technique for preparation of vertebral members utilizing a docking ring which is temporarily applied to the anterior spine to maintain preferred vertebral alignment and to function as a docking plate for an articulating bone removal device.
[0011] U.S. Pat. No. 7,033,362 to McGahan, entitled Instruments and Techniques for Disc Space Preparation, issued Apr. 25, 2006, discloses a removable instrumentation set and method for disc space preparation whereby an intervertebral device is temporarily inserted for the purpose of constraining tissue removal and guiding the position of an intervertebral repair device.
[0012] US Pat. App. 2003/0236526 to Van Hoeck, entitled Adjustable Surgical Guide and Method of Treating Vertebral Members, published Dec. 25, 2003, discloses a removable surgical guide and method with adjustable functionality for the preparation of adjacent vertebra.
[0013] US Pat. App. No. 2006/0247654 to Berry, entitled Instruments and Techniques for Spinal Disc Space Preparation, published Nov. 2, 2006, discloses a removable milling instrument assembly for vertebral endplate preparation which constrains a cutting path obliquely oriented to the axis of the vertebra.
Permanently Implanted Devices
[0014] US Pat. App. 2004/0097925 to Boehm, entitled Cervical Spine Stabilizing System and Method, published May 20, 2004, discloses a permanently implantable spine stabilizing system and method whereby a plate configured to be positively centered along the midline is placed to retain adjacent vertebra in a desired spatial relationship during discectomy and fusion procedures. The disclosed invention uses a series of temporary implants and removable drill templates in an attempt to assure the alignment of the implanted device along the midline of the spinal column. This alignment is typically not considered to be significant in determined the clinical outcome of the procedure and is further considered impractical for the purposes of performing repair procedures on multiple adjacent disk spaces due to the normal scoliotic curvature of the spine.
[0015] US Pat. App. 2005/0149026 to Butler et al., entitled Static and Dynamic Cervical Plate Constructs, published Jul. 7, 2005, describes an implanted cervical bone plate having a graft window located between the bone screw holes for the purposes of providing visualization and access to an intervertebral implant. The device described is applied after the intervertebral space has been repaired and after the implant has been positioned. The specification states specifically that an appropriately “sized dynamic plate is placed over the inserted bone implant”; thereafter the bone plate is located with respect to the implant by viewing the implant through the graft window and secured in place using bone screws.
[0016] Additional bone plate devices are disclosed in U.S. Pat. No. 3,741,205 to Markolf et al, and US Pat. Apps. 2005/0149026 to Butler et al. and 2007/0233107 to Zielinski.
[0017] There remains a need for and advantage to a permanently implantable spinal repair system and related method whereby the implant may be clearly viewed through the vertebral plate both inter-operatively and post-operatively. There is also a need for new systems and methods wherein the intervertebral implant and the bone screws used to secure the plate to the vertebrae can be prevented from backing out from the vertebrae in a quick and effective manner.
SUMMARY OF THE DISCLOSURE
[0018] The invention relates generally to systems and methods for securing adjacent vertebrae in a fixed spacial relationship. In one embodiment, the system includes at least one interbody repair implant, at least one implantable vertebral frame and at least one retention member. In this embodiment, the interbody repair implant is sized to fit in an intervertebral space. The at least one implantable vertebral frame is configured to span between the adjacent vertebrae. The frame is also configured to attach to each of the adjacent vertebra to postoperatively maintain a desired spatial relationship between the vertebrae. The frame has at least one internal aperture there-through for providing visual access to at least a portion of the interbody repair implant, both intra-operatively and post-operatively. The aperture is sized to have a smaller medio-lateral width than that of the interbody repair implant. The at least one retention member is attachable to the frame to cover at least a portion of the aperture. The retention member has a locking portion movable between an unlocked position and a locked position. In this embodiment, the locking portion prevents the retention member from being separated from the frame when in the locked position.
[0019] In some embodiments similar to the above embodiment, the locking portion includes at least one section that contacts a posterior side of the frame when the locking portion is in the locked position. The locking portion may include two sections that contact the posterior side of the frame on opposite sides of the aperture when the locking portion is in the locked position.
[0020] In some embodiments, the retention member includes at least one screw cover portion. The screw cover portion may cover at least part of a screw securing the frame to one of the adjacent vertebrae so as to prevent the screw from backing out of the vertebra. The retention member may include two, four, or more screw cover portions.
[0021] In some embodiments, the retention member includes a transitory locking portion having at least one resilient arm engageable with the frame for maintaining the retention member on the frame before the locking portion is moved from the unlocked position to the locked position.
[0022] In some embodiments, at least a portion of the retention member is radiolucent.
[0023] In some embodiments, the frame is configured to span between and remain postoperatively attached to at least three or at least four adjacent vertebrae. In these embodiments, the frame has at least two or at least three internal apertures there-through, respectively. Each aperture is configured to provide visual access to at least a portion of an interbody repair implant intra-operatively and post-operatively. In these embodiments, the system may include two or three retention members, respectively. Each retention member is attachable to the frame and is configured to cover at least a portion of one of the apertures. Each retention member has a locking portion movable between an unlocked position and a locked position. The locking portion in these embodiments prevents the retention member from being separated from the frame when in the locked position.
[0024] In some embodiments, the retention member is configured to provide visual, tactile and audible feedback when the locking portion is moved between the unlocked position and the locked position.
[0025] According to aspects of the invention, a method of fusing two or more adjacent vertebral bodies in a portion of a spinal column may be provided. In one such embodiment, the method includes the steps of inserting an interbody repair implant into a intervertebral space and securing an implantable vertebral fixation frame to the adjacent vertebral bodies over the implant. These steps are done such that a desired spatial relationship between the vertebrae is maintained. In this embodiment, the fixation frame has an internal aperture there-through for providing visual access to at least a portion of the interbody repair implant intra-operatively and post-operatively. The aperture is sized to have a smaller medio-lateral width than that of the interbody repair implant. This method further includes the steps of installing a retention member to the frame to cover at least a portion of the aperture, and moving a locking portion of the retention member from an unlocked position to a locked position. This locking of the retention member prevents the retention member from being separated from the frame.
[0026] In some embodiments similar to the above method, the locking portion includes at least one section that contacts a posterior side of the frame when the locking portion is in the locked position. The retention member may further include at least one screw cover portion, wherein the screw cover portion covers at least part of a screw securing the frame to one of the adjacent vertebrae. The screw cover portion prevents the screw from backing out of the vertebra. In some embodiments, there are two, four, or more screw cover portions.
[0027] In some embodiments, the retention member includes a transitory locking portion having at least one resilient arm that engages with the frame and maintains the retention member on the frame between the installing and moving steps. The method may include the step of observing the interbody repair implant with postoperative imaging through the retention member.
[0028] In some embodiments, the securing step involves securing the implantable vertebral fixation frame to at least three adjacent vertebral bodies to maintain a desired spatial relationship between the at least three vertebral bodies. The installing and moving steps may each be performed on more than one retention member. In some inventive methods disclosed herein, the retention member is configured to provide visual, tactile and audible feedback during the moving step.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 is an anterior plan view showing an exemplary interbody repair device implanted in an intervertebral space and covered by an implantable vertebral frame secured between two adjacent vertebrae according to aspects of the present invention.
[0030] FIG. 2 is a lateral view showing the repair device and vertebral frame of FIG. 1 .
[0031] FIG. 3 is a perspective view showing the top of the repair device of FIG. 1 with an exemplary retention member installed.
[0032] FIG. 4 is a perspective view of the bottom side of the repair device and retention member of FIG. 3 .
[0033] FIG. 5 is an exploded perspective view showing the repair device and retention member of FIGS. 3 and 4 .
[0034] FIG. 6 is an enlarged perspective view showing an end portion of the exemplary retention member.
[0035] FIG. 7 is a top plan view showing the exemplary retention member with its locking arm removed for clarity.
[0036] FIG. 8 is a bottom view showing the exemplary retention member with its locking arm removed for clarity.
[0037] FIG. 9 is a side view showing the exemplary retention member with its locking arm removed for clarity.
[0038] FIG. 10 is an exploded end view showing the exemplary retention member with its locking arm disassembled.
[0039] FIG. 11A is an exemplary bone screw for use in securing the vertebral frame to adjacent vertebrae.
[0040] FIG. 11B is a perspective view showing the bone screw of FIG. 11A installed in a vertebral frame.
[0041] FIG. 12 is an anterior view depicting a retention member (semi-transparent for clarity) attached to a vertebral frame and in an unlocked position.
[0042] FIG. 13 is an anterior view depicting a retention member (semi-transparent for clarity) attached to a vertebral frame and in a locked position.
[0043] FIG. 14 is a perspective view showing an exemplary vertebral frame configured for spanning three adjacent vertebral bodies.
[0044] FIG. 15 is a perspective view showing an exemplary vertebral frame configured for spanning four adjacent vertebral bodies.
[0045] FIG. 16 is a bottom view showing the exemplary vertebral frames of FIGS. 3 , 14 and 15 .
[0046] FIG. 17 is a perspective view showing the vertebral frame of FIG. 15 attached to four adjacent vertebral bodies.
[0047] FIG. 18 is an anterior view showing the vertebral frame of FIG. 15 attached to four adjacent vertebral bodies.
[0048] FIG. 19 is a lateral cross-sectional view showing the vertebral frame of FIG. 15 attached to four adjacent vertebral bodies.
[0049] FIG. 20 is a cranio-caudal cross-sectional view showing the vertebral frame of FIG. 15 attached to a vertebral body.
[0050] FIG. 21 is an enlarged lateral cross-sectional view showing a portion of the vertebral frame of FIG. 15 .
DETAILED DESCRIPTION
[0051] FIGS. 1 and 2 show portions of an exemplary system constructed according to aspects of the present invention for securing adjacent vertebrae. Such systems are particularly useful for plating anterior surfaces of vertebral bodies of the cervical portion of the human spine, such as for treating compressions of the spine. Additional background and details of tools and surgical procedures associated with these systems can be found in U.S. patent application Ser. No. 12/616,762 entitled “Implantable Vertebral Frame Systems and Related Methods for Spinal Repair”, filed Nov. 11, 2009.
[0052] The exemplary single-level system includes an interbody repair device 100 implanted in an intervertebral space between adjacent vertebral bodies 102 and 104 . In some embodiments, the opposing endplates of adjacent vertebral bodies 102 and 104 are at least partially removed to prepare the intervertebral space to receive repair device 100 . Device 100 may be configured to facilitate the fusion of vertebral bodies 102 and 104 .
[0053] The exemplary system of FIGS. 1 and 2 also includes an implantable vertebral frame 106 configured to span between vertebral bodies 102 and 104 . Two bone screws 108 may be used to rigidly secure frame 106 to each of the vertebral bodies 102 and 104 . In this embodiment, frame 106 is secured to the anterior faces of vertebral bodies 102 and 104 along the medial centerline of the spine. The combination of repair device 100 and vertebral frame 106 may be used to permanently secure vertebral bodies 102 and 104 in a desired position relative to each other, such as for fusing the vertebral bodies together.
[0054] As shown, frame 106 may be provided with an aperture 110 there-through. Aperture 110 may be used to view aspects of repair device 100 , such as its position, during surgery. After surgery, the aperture may be useful in viewing the development of bony ingrowth from the vertebral bodies 102 and 104 into repair device 100 , as will be described further below. In some embodiments, the cranio-caudal dimension of aperture 110 is large enough to view a portion of each vertebral body where it contacts repair device 100 , as shown. In some embodiments, aperture 110 is sized to have a smaller medio-lateral width than that of the repair device 100 . Such an arrangement can allow frame 106 to assist in keeping repair device 100 from migrating in an anterior direction out of the intervertebral space.
[0055] FIGS. 3 and 4 show a retention member 112 attached to vertebral frame 106 and locked in place. In this embodiment, much of the anterior-posterior thickness of retention member 112 is received within a complementary-shaped recess 114 (shown in FIG. 1 ) in the anterior face of frame 106 . This arrangement provides a generally smooth outer contour when retention member 112 is coupled to frame 106 . Retention member 112 may cover aperture 110 as shown. In some embodiments, retention member 112 may serve to help retain repair device 100 in place. In some embodiments, retention member 112 serves to lock screws 108 in place as shown, as will be described in more detail below.
[0056] As seen in FIG. 4 , retention member 112 may include a movable locking arm 116 on its posterior side for locking retention member 112 to frame 106 . In this embodiment, locking arm 116 is operated by inserting a tool (not shown) in a keyed recess 118 on the anterior side of retention member 112 (shown in FIG. 3 ) and rotating locking arm 116 from an unlocked cranio-caudal orientation to a locked medio-lateral orientation, shown in FIG. 4 . Retention member 112 may also include a transitory locking feature such as one or more resilient arms 120 engageable with frame 106 . The transitory locking feature maintains retention member 112 on frame 106 before the locking arm 116 is moved from its unlocked position to its locked position. The construction and operation of these locking features are described in more detail below.
[0057] Referring to FIG. 5 , vertebral frame 106 and retention member 112 are shown separated from each other and from the bottom (posterior) side. Retention member 112 is shown with locking arm 116 in the unlocked position. In this embodiment, retention member 112 is provided with a pair of resilient arms 120 downwardly depending from near each longitudinal end of the retention member. Each arm 120 is L-shaped and has a flange 122 projecting outwardly from its distal end, as best seen in FIG. 6 . Inwardly facing, complementary-shaped recesses 124 may be formed in opposite longitudinal ends of aperture 110 of frame 106 for receiving the projecting flanges 122 . Retention member 112 may be assembled to frame 106 from above by pressing it down over aperture 110 . Beveled leading edges on flanges 122 cause resilient arm 120 to flex inwardly as they come into contact with the opposite sides of aperture 110 . Once retention member 112 is fully received within aperture 110 and recess 114 (shown in FIG. 1 ), resilient arms 120 snap back to urge flanges 122 into recesses 124 , thereby holding retention member 112 in place before locking arm 116 is actuated. With locking arm 116 in the unlocked position, retention member 112 can be removed from frame 106 , such as by inserting a probe or other instrument into one or both of the pockets 125 formed in the anterior aspect of resilient arms 120 (best seen in FIG. 7 ), and applying a force to disengage resilient arms 120 from frame 106 . This can be done interoperatively or during a subsequent revision procedure. A tool may also be inserted into pockets 125 and/or slots 126 surrounding the resilient arms 120 to grasp retention member 112 for removal and/or insertion.
[0058] As can be seen in FIGS. 5 and 6 , in this embodiment retention member has a lower portion 128 that fits within aperture 110 of frame 106 , and a larger flange portion 130 that resides above aperture 110 when coupled to frame 106 . Retention member 112 may be provided with one, two, three, four, or more screw cover portions. In this exemplary embodiment, retention member 112 is provided with four screw cover portions 132 , one located at each corner of the retention member. As best seen in FIGS. 5 and 6 , each screw cover portion 132 is curved and has a notch for receiving a portion of the head of a screw 108 . This arrangement prevents the screws 108 from backing out of the vertebrae once they are installed and retention member 112 is locked in place. FIG. 3 shows the inter-engagement between screw cover portions 132 and screws 108 .
[0059] FIG. 7 shows the top or anterior side of the exemplary retention member 112 . The locking arm and keyed recess assembly is omitted from this view for clarity. As shown, a central hole 134 and counterbore 136 may be provided in the center of retention member 112 for receiving the locking arm and keyed recess assembly, as will be later described. Counterbore 136 allows the assembly to be recessed within retention member 112 .
[0060] FIG. 8 shows the bottom or posterior side of the exemplary retention member 112 . The locking arm and keyed recess assembly is again omitted from this view for clarity.
[0061] FIG. 9 shows a side or lateral view of the exemplary retention member 112 . The locking arm and keyed recess assembly is again omitted from this view for clarity.
[0062] FIG. 10 shows an end or cranio-caudal view of the exemplary retention member 112 . The locking arm and keyed recess assembly is shown with components in an exploded fashion for clarity. Locking arm 116 may be formed on or otherwise rigidly coupled to a cylindrical boss 138 . In this embodiment, boss 138 has a keyed recess 118 (shown in FIG. 3 ) formed through its top surface. Boss 138 is configured to be rotatably received through the bottom side of central hole 134 within retention member 112 . Cap ring 140 may be threaded, press-fit, welded, swaged or otherwise attached around the top of boss 138 . This arrangement sandwiches the bottom of counterbore 136 between locking arm 116 and cap ring 140 , thereby captivating the locking arm assembly on retention member 112 and allowing locking arm 116 to rotate relative thereto. Locking arm 116 is configured to slide along bottom surface 142 , which is shown in FIGS. 8 and 9 . As can be appreciated by viewing the configuration of the four portions 128 that depend from bottom surface 142 shown in FIG. 8 , the locking arm may be oriented along the longitudinal (cranio-caudal axis) of retention member 112 in an unlocked position, or it may be rotated 90 degrees counter-clockwise (when viewed from below as in FIG. 8 ) to a locked position. As shown in FIG. 10 , locking arm 116 has a length that is longer than the width of the lower portion 128 of retention member 112 . As such, the tips of locking arm 116 will extend beyond the bottom surface 142 of retention member 112 when in the locked position, and into recesses 144 formed in the bottom of frame 106 , as shown in FIG. 4 . In this locked position, retention member 112 is securely coupled to frame 106 and bone screws 108 (shown in FIG. 3 ) are prevented from backing out.
[0063] FIGS. 12 and 13 show retention member 112 coupled to vertebral frame 106 from an anterior view to further illustrate the locking of retention member 112 to frame 106 . In both figures, the retention member 112 is shown as being semi-transparent for clarity. FIG. 12 shows locking arm 116 in an unlocked position, while FIG. 13 shows it turned 90 degrees in a clockwise direction to a locked position. According to aspects of the invention, at least one hole 146 may be provided through retention member 112 to align with locking arm 116 when it is either in the unlocked position (as shown in FIG. 12 ), or when it is in the locked position (not shown). Locking arm 116 may have a brightly colored dot on its surface to line up with hole 146 , or locking arm 116 may be made from or coated with a brightly colored material. With this arrangement, a surgeon can clearly see whether locking arm 116 is in the unlocked position (or locked position). A detent feature (not shown) can be provided between locking arm 116 and retention member 112 to provide tactile feedback to a surgeon when locking arm 116 enters a locked position. The detent feature or a similar feature can also be configured to provide audible feedback to a surgeon. Thus, in some embodiments of the invention, a surgeon is provided with visual, tactile and audible feedback when locking arm 116 is moved between the unlocked position and the locked position. In other embodiments, only two, one, or none of these feedback features is provided.
[0064] Referring to FIG. 11A , a proprietary bone screw 108 may be used to secure vertebral frame 106 to the vertebrae it spans. Bone screw 108 includes a head 145 and a threaded shank 147 . Threaded shank 147 may be configured to be self drilling and/or self tapping. Bone screw 108 may be provided with head relief portion 149 to cooperate with screw cover portions 132 of retention member 112 , as previously described. Bone screw 108 may also include a shoulder portion 148 . In some embodiments, shoulder portion 148 has a spherical contour as shown. This contour cooperates with a mating contour on the anterior side of screw holes 154 in frame 106 . This arrangement allows screw 108 to be mounted into a vertebral body at a variable angle relative to frame 106 , as depicted in FIG. 11B . In some embodiments, this variability is defined by a 14 degree included angle. In other embodiments, fixed angle screws are used, or a combination of fixed angle and variable angle screws may be used.
[0065] Referring to FIGS. 14-16 , additional embodiments of the inventive vertebral frame and retainer member are shown. While the previously described frame 106 is configured to span two adjacent vertebral bodies (i.e. a single-level system), vertebral frame 150 shown in FIG. 14 is configured to span three adjacent vertebral bodies (i.e. a two-level system), and vertebral frame 152 shown in FIG. 15 is configured to span four adjacent vertebral bodies (i.e. a three-level system). The posterior side of all three vertebral frames 106 , 150 and 152 and retention members 112 is shown in FIG. 16 .
[0066] The construction and operation of multi-level vertebral frames 150 and 152 is similar to those of single-level frame 106 . A repair implant similar to device 100 shown in FIGS. 1 and 2 may be implanted between each of the adjacent vertebrae connected by these multi-level frames. As with frame 106 , a pair of holes 154 is provided through the frame in these exemplary multi-level embodiments to receive a pair of screws 108 for attaching the frame to each vertebral body. In the exemplary embodiments shown, multiple retention members 112 are used on each frame 150 and 152 to retain screws 108 . Each retention member 112 secures four screws 108 , with the middle screws each being retained by two retention members 112 . Each retention member 112 may be symmetrical and identical, thereby allowing it to be put in any position on the frame and in either orientation. This arrangement reduces the part count in surgical kits containing one or more types of vertebral frames and simplifies the surgical procedures for implanting them. In other embodiments (not shown), a single retention member may be used. As previously described, each retention member may have a transitory locking portion having at least one resilient arm engageable with the frame for maintaining the retention member on the frame before a locking portion is moved from an unlocked position to a locked position.
[0067] FIGS. 17 and 18 show vertebral frame 152 implanted across four adjacent vertebral bodies 102 , 104 , 154 and 156 .
[0068] FIG. 19 shows a medio-lateral looking cross-section of the vertebral frame 152 and adjacent vertebral bodies of FIGS. 17 and 18 , taken along a cranio-caudal line running through the central axis of four screws 108 on one side of frame 152 .
[0069] FIG. 20 shows a cranio-caudal looking cross-section of a portion of vertebral frame 152 and a vertebral body of FIGS. 17 and 18 , taken along a medio-lateral line running through the central axis of two adjacent screws 108 in a single vertebral body.
[0070] Aspects of the present invention can also be utilized to construct vertebral frames spanning more than four vertebral bodies.
[0071] According to aspects of the invention, the vertebral frames 106 , 150 and 152 are configured to be low-profile for minimal interference with surrounding anatomy. In some embodiments, the vertebral frames are 2.1 mm at their thickest points. 1.2 mm leading and latereal edges may be provided as shown for easy insertion and in-situ adjustment. In some embodiments, the vertebral frames are 18 mm at their greatest width, and 13 mm at their narrowest width. The aperture(s) of each frame may be configured to be about 8 mm wide and about 12 mm long. The vertebral frames may have a pre-lordosed design as shown. Frames may be configured to allow translation up to about 1.5 mm per level. In some embodiments, the vertebral frames are made of titanium.
[0072] Surgical kits may be provided that include various sizes of vertebral frames. In some embodiments, the kits include single-level plates ranging from about 22 mm to about 34 mm long, In some embodiments, the kits include two-level plates ranging from about 36 mm to about 55 mm long. In some embodiments, the kits include three-level plates ranging from about 50 mm to about 77 mm long. In some embodiments, the kits include more than one type of vertebral frame. The kits may also include a range of self-drilling and self-tapping screws, fixed-angle screws, variable-angle screws, and recovery screws. In some embodiments, screws having a 4.0 mm nominal diameter are provided, and recovery screws having a 4.5 mm nominal diameter are also provided.
[0073] In some embodiments, retention member 112 is made of PEEK or another radiolucent material. This allows bone growth into an implant beneath retention member 112 to be viewed with various imaging techniques. Locking arm 116 may be made of titanium or another radio-opaque material so its locked status can be confirmed by imaging.
[0074] One exemplary method of installing a vertebral frame according to aspects of the invention is as follows. An incision is made and the anterior surfaces of the cervical vertebral bodies to be plated are exposed, as is well known in the art. The vertebral bodies may be distracted at this point to provide a desired spacial arrangement, to provide room to prepare the intervertebral space(s), and/or to insert the repair implant(s) 100 . The intervertebral space(s) may be prepared, such as by removing at least portions of the disk annulus fibrosus, disk nucleus, and/or vertebral body endplates. The repair implant(s) may then be inserted between the adjacent vertebral bodies. Vertebral frame 106 , 150 or 152 is then placed over the adjacent vertebral bodies covering the repair implant(s). The vertebral frame is typically placed on the anterior surfaces of the vertebral bodies along the medial centerline of the spine, and centered cranio-caudally over each repair implant 100 . The aperture(s) 110 in the frame allow the surgeon to view the positioning of the implant(s) 100 during the procedure.
[0075] Once the vertebral frame 106 , 150 or 152 is in the desired position on the vertebral bodies, it may be secured in place with bone screw 108 . In the exemplary embodiments disclosed herein, two screws 108 are used for each vertebral body involved in the procedure. The screws may be self drilling and/or self tapping. Alternatively, holes may be pre-drilled in the bone before inserting the screws. The vertebral frame may be used as a drilling template, or a separate drilling template may be temporarily placed over the vertebral bodies for drilling prior to placement of the vertebral frame. In some embodiments, a separate drill guide may be attached to the drilling template or vertebral frame to aid in drilling and/or tapping.
[0076] Bone screws 108 are tightened, thereby securing vertebral frame 106 , 150 or 152 to the vertebral bodies. The vertebral frame cooperates with repair implant(s) 100 to hold the vertebral bodies in the desired position postoperatively. Retention member(s) 112 may now be installed in the vertebral frame. As previously described, each retention member 112 may be placed over and partially into an aperture 110 , and snapped into place by transitory locking features such as resilient arms 120 shown in FIG. 5 . With a single 90 degree twist of each keyed recess 118 (shown in FIG. 3 ), the retention member 112 is locked into place by locking arm 116 (shown in FIG. 4 ), thereby fully securing implant 100 and four bone screws 108 . As previously described, visual, tactile and audible feedback may be provided to the surgeon when the locking portion is moved between the unlocked position and the locked position. Each retention member 112 may be removed, if desired, by turning its keyed recess 118 in the opposite direction and prying the retention member 112 away from the frame against the force of the resilient arms 120 . Once all retention members 112 are in place and locked, the plating procedure may be completed by closing the incision, as is well known in the art.
[0077] In some procedures it is desired that boney ingrowth from the vertebral bodies and/or bone growth material placed in repair implant(s) 100 allows the adjacent vertebral bodies to fuse together. Post-operative imaging can be used to monitor the progress of this healing process by viewing the implant-to-vertebral body interfaces through the aperture(s) 110 of the vertebral frame 106 , 150 or 152 . This is enabled by the large viewing aperture(s) 110 provided by aspects of the present invention along with retention member(s) 112 being made from a radio-translucent material.
[0078] While inventive vertebral frame systems and associated methods have been described in some detail by way of illustration, such illustration is for purposes of clarity of understanding only. It will be readily apparent to those of ordinary skill and in the art in light of the teachings herein that certain changes and modifications may be made thereto without departing from the spirit and scope of the appended claims.
[0079] All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. | The invention relates generally to systems and methods for securing adjacent vertebrae in a fixed spacial relationship. In one embodiment, the system includes at least one interbody repair implant, at least one implantable vertebral frame and at least one retention member. In this embodiment, the interbody repair implant is sized to fit in an intervertebral space. The at least one implantable vertebral frame is configured to span between the adjacent vertebrae. The frame is also configured to attach to each of the adjacent vertebra to postoperatively maintain a desired spatial relationship between the vertebrae. The frame has at least one internal aperture there-through for providing visual access to at least a portion of the interbody repair implant, both intra-operatively and post-operatively. Methods of fusing two or more adjacent vertebral bodies in a portion of a spinal column are also disclosed. One such method includes the steps of inserting an interbody repair implant into a intervertebral space, securing an implantable vertebral fixation frame to the adjacent vertebral bodies over the implant, installing a retention member to the frame to cover at least a portion of the aperture, and moving a locking portion of the retention member from an unlocked position to a locked position. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. Ser. No. 11/620,318 (filed Jan. 5, 2007) which is a continuation-in-part of U.S. Ser. No. 10/544,150 (filed Aug. 1, 2005), which is a national stage entry of PCT/US01/46841 (filed Nov. 8, 2001) which claims the benefit of U.S. Provisional Patent Application Ser. Nos. 60/246,689 (filed Nov. 8, 2000) 60/246,707 (filed Nov. 8, 2000) 60/246,708 (filed Nov. 8, 2000) and 60/246,709 (filed Nov. 8, 2000). The contents of the aforementioned applications are hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of ophthalmic solutions and their uses. In particular the invention relates to contact lens cleaning solutions, contact lens rinsing and storing solutions, solution to deliver active pharmaceutical agents to the eye, solutions for disinfecting ophthalmic devices and the like.
BACKGROUND
[0003] The present invention relates to the field of ophthalmic solutions and especially to the aspects of preservative efficacy and comfort after prolonged use. These ophthalmic solutions have been used for some period of time and are available as over the counter products. Solutions that are used in direct contact with corneal tissue such as the delivery of active pharmaceutical agent to the eye, or indirectly, such as the cleaning, conditioning or storage of devices that will come in contact with corneal tissue, such as contact lenses, there is a need to insure that these solution do not introduce sources of bacterial or other microbial infection. Thus preservatives are included to reduce the viability of microbes in the solution and to lessen the chance of contamination of the solution by the user since many of the solutions are bought, opened, used, sealed and then reused.
[0004] State of the art preservative agents include polyhexamethylene biguanide (PHMB), POLYQUAD™, chlorhexidine, and benzalkonium chloride, and the like, all of which at some concentration irritate corneal tissue and lead to user discomfort. Therefore, a solution that employs a given amount of a preservative agent, but which is made more effective by addition of an agent that is not a preservative agent would be desired.
SUMMARY OF THE INVENTION
[0005] The present invention relates to improved ophthalmic solutions that employ select
[0006] B vitamins; pyridoxine and its salts; and thiamine and its salts in order to more effectively preserve solutions and to reduce the degree to which cationic preservatives will deposit on contact lenses. Ophthalmic solutions are here understood to include contact lens treatment solutions, such as cleaners, soaking solutions, conditioning solutions and lens storage solutions, as well as wetting solutions and in-eye solutions for treatment of eye conditions.
DETAILED DESCRIPTION
[0007] The solutions specifically described herein have 0.001 to about 10.0 weight percent of select B vitamins; pyridoxine and its salts; and thiamine and its salts in combination with other active ingredients useful in ophthalmic solutions such as tonicity agent, buffers, preservatives, surfactants, and antimicrobial agents.
[0008] The B family of vitamins includes thiamine (B1), riboflavin (B2), niacin (B3), dexpanthenol, panthenol, pantothenic acid (B5), pyridoxine (B6), and cobalamin (B 12). While each form of B vitamin is chemically distinct, they are often found in the same nutritional sources and hence deficiency in one is often related to deficiency in the other forms. Metabolically, they work with one another to bolster metabolism, enhance immune and nervous system function, maintain healthy skin and muscle tone, and promote cell growth and division. They may also relieve stress, depression, and cardiovascular disease. A deficiency in one B vitamin often means that intake of all B vitamins is low which is why B as a nutritional source are often provided in multivitamin or B-complex formulae.
[0009] Niacin contributes to a great number of bodily processes. Among other things niacin helps convert food into energy, build red blood cells, synthesize hormones, fatty-acids and steroids. The body uses niacin in the process of releasing energy from carbohydrates. Niacin is also needed to form fat from carbohydrates and to process alcohol. Niacin also helps regulate cholesterol.
[0010] Pyridoxine is needed to make serotonin, melatonin, and dopamine. Vitamin B-6 is an essential nutrient in the regulation of mental processes and possibly assists in mood and many other health concerns
[0011] Cobalamin is needed for normal nerve cell activity. Vitamin B-12 is also needed for DNA replication, and production of the mood-affecting substance called SAMe (S-adenosyl-L-methionine). Vitamin B-12 works with folic acid to control homocysteine levels. An excess of homocysteine, which is an amino acid (protein building block), may increase the risk of heart disease, stroke, and perhaps osteoporosis and Alzheimer's disease.
[0012] Other compounds such as folic acid or folate are active in combination with the B vitamins and are needed to synthesize DNA. DNA allows cells to replicate normally. Folic acid is especially important for the cells of a fetus when a woman is pregnant. Folic Acid is also needed to make SAMe and keep homocysteine levels in the blood from rising. Folic Acid (pteroylglutamic acid) is not active as such in the mammalian organism, but rather is enzymatically reduced to tetrahydrofolic acid (THFA), the coenzyme form. An interrelationship exists with vitamin B12 and folate methabolism that further involves vitamin B6: folate coenzymes participate in a large number of metabolic reactions in which there is a transfer of a one-carbon unit.
[0013] Pantothenic Acid, also sometimes referred to as coenzyme A, is the physiologically acitive form of pantothenic acid, and serves a vital role in metabolism as a coenzyme for a variety of enzyme-catablyzed reactions involving transfer of acetyl (two-carbon) groups. Surprisingly, pantothenic acid is essential for the growth of various microorganisms, including many strains of pathogenic bacteria.
[0014] In the form of contact lens rinsing solutions and/or pharmaceutical agent delivery system the solutions will contain, in addition to the lens or the pharmaceutical agent 0.00001 to about 10.0 weight percent of one of the vitamin B forms or a vitamin B co-metabolite chosen from the group including, but not limited to, thiamine (B1), riboflavin (B2), niacin (B3), dexpanthenol, panthenol, pantothenic acid (B5), pyridoxine (B6), and cobalamin (B12); and at least 0.00001 weight percent of a preservative.
[0015] The preservatives that are specifically useful are cationic preservatives such as polyhexamethylene biguanide (phmb), POLYQUAD™, chlorhexidne, and benzalkonium chloride, as well as other cationic preservatives that may prove useful in the present invention as well. The cationic preservatives are used at effective amounts as preservatives, and in the instance of PHMB from 0.0001 percent by weight to higher levels of about 0.01 weight percent.
[0016] The formulations may also include buffers such as phosphates, bicarbonate, citrate, borate, ACES, BES, BICINE, BIS-Tris Propane, HEPES, HEPPS, imidazole, MES, MOPS, PIPES, TAPS, TES, TRIS and Tricine.
[0017] Surfactants that might be employed include polysorbate surfactants, polyoxyethylene surfactants, phosphonates, saponins and polyethoxylated castor oils, but preerrably the polyethoxylated castor oils. These surfactants are commercially available. The polyethoxylated castor oils are sold by BASF under the trademark Cremophor.
[0018] The solutions of the present invention may contain other additives including but not limited to buffers, tonicity agents, demulcents, wetting agents, preservatives, sequestering agents (chelating agents), surface active agents, and enzymes. In one embodiment between about 0.01% and 5.0% of a simple saccharide is present. Examples of simple saccharides include mannitol; sorbitol; sucrose; dextrose and glycerin.
[0019] Other aspects include adding to the solution from 0.001 to 1 weight percent chelating agent (preferably disodium EDTA) and/or additional microbicide, (preferably 0.00001 to 0.1) weight percent polyhexamethylene biquanide (PHMB, N-alkyl-2-pyrrolidone, chlorhexidine, polyquaternium-1, hexetidine, bronopol, alexidine, low concentrations of hydrogen peroxide, and ophthalmologically acceptable salts thereof.
[0020] Ophthalmologically acceptable chelating agents useful in the present invention include amino carboxylic acid compounds or water-soluble salts thereof, including ethylenediaminetetraacetic acid, nitrilotriacetic acid, diethylenetriamine pentaacetic acid, hydroxyethylethylenediaminetriacetic acid, 1,2-diaminocyclohexanetetraacetic acid, ethylene glycol bis (beta-aminoethyl ether) in N, N, N′, N′ tetraacetic acid (EGTA), aminodiacetic acid and hydroxyethylamino diacetic acid. These acids can be used in the form of their water soluble salts, particularly their alkali metal salts. Especially preferred chelating agents are the di-, tn- and tetra-sodium salts of ethylenediaminetetraacetic acid (EDTA), most preferably disodium EDTA (Disodium Edetate).
[0021] Other chelating agents such as citrates and polyphosphates can also be used in the present invention. The citrates which can be used in the present invention include citric acid and its mono-, di-, and tri-alkaline metal salts. The polyphosphates which can be used include pyrophosphates, triphosphates, tetraphosphates, trimetaphosphates, tetrametaphosphates, as well as more highly condensed phosphates in the form of the neutral or acidic alkali metal salts such as the sodium and potassium salts as well as the ammonium salt.
[0022] The pH of the solutions should be adjusted to be compatible with the eye and the contact lens, such as between 6.0 to 8.0, preferably between 6.8 to 7.8 or between 7.0 to 7.6. Significant deviations from neutral (pH 7.3) will cause changes in the physical parameters (i.e. diameter) in some contact lenses. Low pH (pH less than 5.5) can cause burning and stinging of the eyes, while very low or very high pH (less than 3.0 or greater than 10) can cause ocular damage.
[0023] The additional preservatives employed in the present invention are known, such as polyhexamethylene biguanide, N-alkyl-2-pyrrolidone, chlorhexidine, polyhexamethylenebiguanide, alexidine, polyquaternium-1, hexetidine, bronopol and a very low concentration of hydrogen peroxide, e.g., 30 to 200 ppm.
[0024] The solutions of the invention are compatible with both rigid gas permeable and hydrophilic contact lenses during storage, cleaning, wetting, soaking, rinsing and disinfection.
[0025] A typical aqueous solution of the present invention may contain additional ingredients which would not affect the basic and novel characteristics of the active ingredients described earlier, such as tonicity agents, surfactants and viscosity inducing agents, which may aid in either the lens cleaning or in providing lubrication to the eye. Suitable tonicity agents include sodium chloride, potassium chloride, glycerol or mixtures thereof The tonicity of the solution is typically adjusted to approximately 240-310 milliosmoles per kilogram solution (mOsm/kg) to render the solution compatible with ocular tissue and with hydrophilic contact lenses. In one embodiment, the solution contains 0.01 to 0.2 weight percent sodium chloride. The important factor is to keep the concentrations of such additives to a degree no greater than that would supply a chloride concentration of no greater than about 0.2 mole percent.
[0026] Suitable viscosity inducing agents can include lecithin or the cellulose derivatives such as hydroxyethylcellulose, hydroxypropylmethylcellulose and methylcellulose in amounts similar to those for surfactants, above.
EXAMPLE 1
[0027] Formulations containing Pyridoxine HCl (Spectrum) and Thiamine HCl (Fisher) were prepared in a 0.2% phosphate buffer. The solutions were made isotonic with sodium chloride and preserved with polyhexamethylene biguanide at 0.0001%. The pH was adjusted to 7.2 with either 1 N sodium hydroxide or 1 N hydrochloric acid. The in vitro microbicidal activity of the solutions was determined by exposing C. albicans to 10 ml of each solution at room temperature for 4 hours. Subsequently, an aliquot of each solution was serial diluted onto agar plates and incubated for 48 hours at elevated temperatures. At the conclusion of the incubation period the plates are examined for the development of colonies. The log reduction was determined based on a comparison to the inoculum control. The following table provides the results of the in vitro studies.
[0000]
Additive
4 Hour Log Reduction
Pyridoxine HCl (0.5%)
2.0
Thiamine HCl (0.5%)
1.0
Buffer Control
0.8
[0028] The solution containing pyridoxine HCl and thiamine HCl showed an improvement in the activity against C. albicans as compared to the buffer control.
EXAMPLE 2
[0029] Formulations containing dexpanthenol were prepared in a 0.25% Bis-Tris
[0030] Propane buffer. The solutions were made isotonic with sodium chloride and preserved with polyhexamethylene biquanide at 0.00005%. The pH was adjusted to 7.2 with either 1 N sodium hydroxide or 1 N hydrochloric acid. The in vitro microbicidal activity of the solutions was determined by exposing C. albicans to 10 ml of each solution at room temperature for 4 hours. Subsequently, an aliquot of each solution was serial diluted onto agar plates and incubated for 48 hours at elevated temperatures. At the conclusion of the incubation period the plates are examined for the development of colonies. The log reduction was determined based on a comparison to the inoculum control. The following table provides the results of the in vitro studies.
[0000]
Log
Reduction
C albicans
Buffer
Additive
Preservative
Dexpanthenol
4 hour
Bis-Tris
Cremophor 0.20%
PHMB 0.5
None
3.8
Propane
Inositol 3.0%
ppm
0.25%
Allantoin 0.1%
Bis-Tris
Cremophor 0.20%
PHMB 0.5
Dexpanthenol
4.9
Propane
Inositol 3.0%
ppm
0.1%
0.25%
Allantoin 0.1%
[0031] This data shows that the dexpanthenol has improved preservative efficacy over a solution with a preservative alone.
EXAMPLE 3
[0032] Formulations containing Dexpanthanol (Spectrum), Pyridoxine HCl (Spectrum) Thiamine HCl (Spectrum), and no Vitamin B control were prepared in a 0.5% Tris buffer containing 0.6% sodium chloride. The pH was adjusted with 1 N HCl to a final pH of 7.2. Polyhexamethylene biquanide (PHMB) at 0.0001% was added to each formulation. The in vitro anti-microbial activity of the solutions was determined by exposing E. coli to 10 ml of each solution at room temperature for 1 hours. Subsequently, an aliquot of each solution was serial diluted onto agar plates and incubated for 48 hours at elevated temperatures. At the conclusion of the incubation period the plates are examined for the development of colonies. The log reduction was determined based on a comparison to the inoculum control. The following table provides the results of the in vitro studies.
[0000]
Log Reduction
Solution
at 1 hr
0.5% Dexpanthenol
0.5% Tris
1 ppm PHMB
4.82
0.5% Pyridoxine HCl
0.5% Tris
1 ppm PHMB
4.34
0.5% Thiamine HCl
0.5% Tris
1 ppm PHMB
5.12
None
0.5% Tris
1 ppm PHMB
0.42
[0033] The results showed an enhancement of the preservative in the presence of the Dexpanthanol, Pyridoxine, and Thiamine.
EXAMPLE 4
[0034] Formulations containing Dexpanthanol (Spectrum), Pyridoxine HCl (Spectrum)
[0035] Thiamine HCl (Spectrum), and no Vitamin B control were prepared in a 0.5% Tris buffer containing 0.6% sodium chloride. The pH was adjusted with 1 N HCl to a final pH of 7.2. Benzalkonium Chloride (BAK) at 0.0025% was added to each formulation. The in vitro anti-microbial activity of the solutions was determined by exposing E. coli to 10 ml of each solution at room temperature for 1 hour. Subsequently, an aliquot of each solution was serial diluted onto agar plates and incubated for 48 hours at elevated temperatures. At the conclusion of the incubation period the plates are examined for the development of colonies. The log reduction was determined based on a comparison to the inoculum control. The following table provides the results of the in vitro studies.
[0000] Log Reduction Solution at 1 hr 0.5% Dexpanthenol 0.5% Tris 25 ppm BAK >5.12 0.5% Pyridoxine HCl 0.5% Tris 25 ppm BAK >5.12 None 0.5% Tris 25 ppm BAK 3.30
The results showed an enhancement of the preservative in the presence of the Dexpanthanol and Pyridoxine. | The present invention relates to improved ophthalmic solutions that employ select B vitamins; pyridoxine and its salts; and thiamine and its salts in order to more effectively preserve solutions and to reduce the degree to which cationic preservatives will deposit on contact lenses. Ophthalmic solutions are here understood to include contact lens treatment solutions, such as cleaners, soaking solutions, conditioning solutions and lens storage solutions, as well as wetting solutions and in-eye solutions for treatment of eye conditions. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to simplifying a manufacturing method and improving the accuracy of manufacturing an actuator that moves a fiber of a scanning endoscope.
[0003] 2. Description of the Related Art
[0004] U.S. Pat. No. 6,294,775 discloses a scanning endoscope, which photographs and/or films an optical image of an observation area by scanning the observation area with light shined on a minute point in the area and successively capturing reflected light at the illuminated points. In a general scanning endoscope, light for illumination is transmitted through an optical fiber from a stationary incident end to a movable emission end and a scanning operation is carried out by successively moving the emission end of the optical fiber.
[0005] The structure of the emission end of an optical fiber in a general scanning endoscope is explained using FIG. 26 . As shown in FIG. 26 , the actuator 54 ′ is mounted near an emission end of an illumination fiber 53 ′. The fiber actuator 54 ′ comprises a bending block 54 ′ b and a support block 54 ′ s.
[0006] The bending block 54 ′ b is shaped cylindrically. The illumination fiber 53 ′ is inserted through the cylindrical bending block 54 ′ b . The illumination fiber 53 ′ is supported at the forward end of the bending block 54 ′ b by the supporting block 54 s.
[0007] The supporting block 54 ′ s is shaped as a right circular cone so that the angle between a generatrix line and the base is 45 degrees. By shaping the supporting block 54 ′ s in this manner, the illumination fiber 53 ′ can be repeatedly bent without breaking by a bending motion of the bending block 54 ′ b that is transmitted through the supporting block 54 ′ s.
[0008] In order to form the supporting block 54 ′ s in the above-mentioned shape, when the illumination fiber 53 ′ is inserted through the bending block 54 ′ b , an adhesive is applied to the forward end of the bending block 54 ′ b , and before it solidifies an operator transforms the adhesive to a right circular cone by vibrating the illumination fiber 53 ′ along the axial direction of the bending block 54 ′ b . The supporting block 54 ′ s is formed by the transformed adhesive solidifying as such a shape.
[0009] In the above manufacturing method it is difficult to adjust the length of the illumination fiber 53 ′ that protrudes from the bending block 54 ′ b . It is also difficult to accurately shape the supporting block 54 ′ s in the form of a right circular cone by the above-manufacturing method. As a result, increasing the yield of manufactured parts within required tolerance levels is difficult.
SUMMARY OF THE INVENTION
[0010] Therefore, an object of the present invention is to improve a manufacturing yield by making a bending block to support the illumination fiber so that the illumination fiber can sufficiently withstand the movements required of it during scanning.
[0011] According to the present invention, a scanning endoscope, comprising a light transmitter, an actuator, and a force transmitter, is provided. The light transmitter transmits light received at a first incident end to a first emission end. The light transmitter emits a beam of the light exiting the first emission end. The light transmitter is flexible. A longitudinal direction of the light transmitter is a first direction. The actuator is mounted near the first emission end. The actuator bends the light transmitter in a second direction by pushing a side of the light transmitter in the second direction. The second direction is perpendicular to the first direction. A force transmitter is oriented lengthwise in the first direction. The force transmitter is elastic. The force transmitter is positioned between the light transmitter and the actuator. The force transmitter exerts a pushing force supplied by the actuator on the side of the light transmitter while the force transmitter is deformed elastically toward the first direction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The objects and advantages of the present invention will be better understood from the following description, with reference to the accompanying drawings in which:
[0013] FIG. 1 is a schematic illustration of a scanning endoscope apparatus comprising a scanning endoscope of the first to seventh embodiments of the present invention;
[0014] FIG. 2 is a block diagram schematically showing the internal structure of the scanning endoscope processor;
[0015] FIG. 3 is a block diagram schematically showing the internal structure of the scanning endoscope of the first embodiment;
[0016] FIG. 4 is a cross-sectional view along the axial direction of the hollow tube schematically showing the structure of the fiber actuator of the first embodiment;
[0017] FIG. 5 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator of the first embodiment;
[0018] FIG. 6 is a front view of the fiber actuator in the first embodiment as seen from the emission end of the illumination fiber;
[0019] FIG. 7 is a perspective view of the fiber actuator in the first embodiment;
[0020] FIG. 8 is a cross-sectional view along the axial direction of the bending block illustrating the deformation of the supporting block at the moment when bending begins;
[0021] FIG. 9 is a cross-sectional view of a plane that includes a center line of the illumination fiber to illustrate the restoring force applied to the illumination fiber by the supporting block when the supporting block deforms elastically;
[0022] FIG. 10 is a cross-sectional view of a plane that includes a center line of the illumination fiber to illustrate the force applied to the illumination fiber by the supporting block that is assumed to be made of a solid material;
[0023] FIG. 11 is a graph illustrating the changing position of the emission end in the second and third directions;
[0024] FIG. 12 illustrates a spiral course along which the emission end of the illumination fiber is moved by the fiber actuator;
[0025] FIG. 13 illustrates the light emitted from the lens;
[0026] FIG. 14 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator of the second embodiment;
[0027] FIG. 15 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator of the third embodiment;
[0028] FIG. 16 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator of the fourth embodiment;
[0029] FIG. 17 is a conceptual view of the intensities of the dispersed restoring forces applied to the side of the illumination fiber in the first embodiment;
[0030] FIG. 18 is a conceptual view of the intensities of the dispersed restoring forces applied to the side of the illumination fiber in the fourth embodiment;
[0031] FIG. 19 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator of the fifth embodiment;
[0032] FIG. 20 is a front view of the fiber actuator in the fifth embodiment as seen from the emission end of the illumination fiber;
[0033] FIG. 21 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator of the sixth embodiment;
[0034] FIG. 22 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator of the seventh embodiment;
[0035] FIG. 23 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator with the center of mass shifted in the opposite direction of the second embodiment;
[0036] FIG. 24 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator with the center of mass shifted in the opposite direction of the third embodiment;
[0037] FIG. 26 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of the fiber actuator with the center of mass shifted in the opposite direction of the sixth embodiment; and
[0038] FIG. 26 is a cross-sectional view along the axial direction of the bending block schematically showing the structure of a fiber actuator in a prior art.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] The present invention is described below with reference to the embodiment shown in the drawings.
[0040] In FIG. 1 , the scanning endoscope apparatus 10 comprises a scanning endoscope processor 20 , a scanning endoscope 50 , and a monitor 11 . The scanning endoscope processor 20 is connected to the scanning endoscope 50 and the monitor 11 .
[0041] Hereinafter, an emission end of an illumination fiber (not depicted in FIG. 1 ) and incident ends of image fibers (not depicted in FIG. 1 ) are ends mounted in the distal end of the insertion tube 51 of the scanning endoscope 50 . In addition, an incident end of the illumination fiber (first incident end) and emission ends of the image fibers are ends mounted in a connector 52 that connects to the scanning endoscope processor 20 .
[0042] The scanning endoscope processor 20 provides light that is shined on an observation area (see “OA” in FIG. 1 ). The light emitted from the scanning endoscope processor 20 is transmitted to the distal end of the insertion tube 51 through the illumination fiber (light transmitter), and is directed towards one point in the observation area. Light reflected from the illuminated point is transmitted from the distal end of the insertion tube 51 to the scanning endoscope processor 20 .
[0043] The direction of the emission end of the illumination fiber (first emission end) is changed by a fiber actuator (not depicted in FIG. 1 ). By changing the direction, the observation area is scanned with the light emitted from the illumination fiber. The fiber actuator is controlled by the scanning endoscope processor 20 .
[0044] The scanning endoscope processor 20 receives reflected light that is scattered at the illuminated point, and generates a pixel signal according to the amount of received light. One frame of an image signal is generated by generating pixel signals corresponding to the illuminated points dispersed throughout the observation area. The generated image signal is transmitted to the monitor 11 , where an image corresponding to the received image signal is displayed.
[0045] As shown in FIG. 2 , the scanning endoscope processor 20 comprises a light-source unit 30 , a light-capturing unit 21 , a scanning driver 22 , an image-processing circuit 23 , a timing controller 24 , a system controller 25 , and other components.
[0046] The light-source unit 30 comprises red, green, and blue lasers (not depicted) that emit red, green, and blue laser beams, respectively. The red, green, and blue laser beams are mixed into white light, which is emitted from the light-source unit 30 .
[0047] The white light emitted from the light-source unit 30 is supplied to the illumination fiber 53 . The scanning driver 22 controls the fiber actuator 54 so that the movements of the emission end of the illumination fiber 53 follow a predetermined course.
[0048] The reflected light at the illuminated point within the observation area is transmitted to the scanning endoscope processor 20 by the image fibers 55 mounted in the scanning endoscope 50 . The transmitted light is made incident on the light-capturing unit 21 .
[0049] The light-capturing unit 21 generates a pixel signal according to the amount of the transmitted light. The pixel signal is transmitted to the image-processing circuit 23 , which stores the received pixel signal in the image memory 26 . Once pixel signals corresponding to the illuminated points dispersed throughout the observation area have been stored, the image-processing circuit 23 carries out predetermined image processing on the pixel signals, and then one frame of the image signal is transmitted to the monitor 11 via the encoder 27 .
[0050] By connecting the scanning endoscope 50 to the scanning endoscope processor 20 , optical connections are made between the light-source unit 30 and the illumination fiber 53 mounted in the scanning endoscope 50 , and between the light-capturing unit 21 and the image fibers 55 . In addition, by connecting the scanning endoscope 50 to the scanning endoscope processor 20 , the fiber actuator 54 mounted in the scanning endoscope 50 is electrically connected to the scanning driver 22 .
[0051] The timing for carrying out the operations of the light-source unit 30 , the light-capturing unit 21 , the scanning driver 22 , the image-processing circuit 23 , and the encoder 27 is controlled by the timing controller 24 . In addition, the timing controller 24 and other components of the endoscope apparatus 10 are controlled by the system controller 25 . A user can input some commands to the input block 28 , which comprises a front panel (not depicted) and other mechanisms.
[0052] Next, the structure of the scanning endoscope 50 is explained. As shown in FIG. 3 , the scanning endoscope 50 comprises the illumination fiber 53 , the fiber actuator 54 , the image fibers 55 , a lens 56 and other components.
[0053] The illumination fiber 53 and the image fibers 55 are arranged inside the scanning endoscope 50 from the connector 52 to the distal end of the insertion tube 51 . As described above, a laser beam of the white light emitted by the light-source unit 30 is incident on the incident end of the illumination fiber 53 . The incident white light is transmitted to the emission end of the illumination fiber 53 .
[0054] A solid hollow tube 57 is mounted at the distal end of the insertion tube 51 (see FIG. 4 ). The hollow tube 57 is positioned so that the axial direction of the distal end of the insertion tube 51 is parallel to a first direction that is an axial direction of the hollow tube 57 .
[0055] The illumination fiber 53 is supported inside the hollow tube 57 by the fiber actuator 54 . The illumination fiber 53 is positioned in the hollow tube 57 so that the axial direction of the hollow tube 57 is parallel to a longitudinal direction of the insertion tube 51 that is not moved by the fiber actuator 54 .
[0056] The fiber actuator 54 comprises a supporting block 54 s (force transmitter) and a bending block 54 b (actuator). As shown in FIG. 5 , the bending block 54 b is shaped cylindrically. The supporting block 54 s is a metal coil spring with dimensions so that the outside and inside diameters of the coil spring are substantially equal to the inside diameter of the cylindrical bending block 54 b and the outside diameter of the illumination fiber 53 , respectively.
[0057] The illumination fiber 53 is inserted through the hollow interior of the coil-shaped supporting block 54 s . The illumination fiber 53 is supported by the supporting block 54 s as the emission end of the illumination fiber 53 protrudes from the supporting block 54 s.
[0058] The supporting block 54 s is inserted into the cylindrical bending block 54 b. The position of the supporting block 54 s is fixed in the bending block 54 b so that the end of the supporting block 54 s nearest to the emission end of the illumination fiber 53 protrudes from the bending block 54 b. Accordingly, the supporting block 54 s is positioned between the bending block 54 b and the illumination fiber 53 in the radial direction.
[0059] As shown in FIG. 6 , first and second bending elements 54 b 1 and 54 b 2 are fixed on the bending block 54 b. The first and second bending elements 54 b 1 and 54 b 2 are pairs of two piezoelectric elements. In addition, the first and second bending elements 54 b 1 and 54 b 2 expand and contract along the axis direction of the cylindrical bending block 54 b (i.e., the first direction) on the basis of a fiber driving signal transmitted from the scanning driver 22 .
[0060] Two piezoelectric elements that constitute the first bending element 54 b 1 are fixed on the outside surface of the cylindrical bending block 54 b so that the axis of the cylindrical bending block 54 b is between the piezoelectric elements and so that the piezoelectric elements are linearly arranged in a second direction that is perpendicular to the first direction. In addition, two piezoelectric elements that constitute the second bending element 54 b 2 are fixed on the outside surface of the cylindrical bending block 54 b at a location that is 90 degrees circumferentially from the first bending element 54 b 1 around the axis of the cylindrical bending block 54 b.
[0061] As shown in FIG. 7 , the bending block 54 b bends along the second direction by expanding one of the piezoelectric elements that constitute the first bending element 54 b 1 and contracting the other at the same time.
[0062] In addition, the bending block 54 b bends along a third direction by expanding one of the piezoelectric elements that constitute the second bending element 54 b 2 and contracting the other at the same time. The piezoelectric elements constituting the second bending element 54 b 2 are linearly arranged in the third direction.
[0063] The illumination fiber 53 is flexible. The side of illumination fiber 53 is pushed along the second and/or third directions by the bending block 54 b via the supporting block 54 s (force transmitter), and the illumination fiber 53 bends toward the second and/or third directions, which are perpendicular to the longitudinal direction of the illumination fiber 53 . The emission end of the illumination fiber 53 is moved by bending the illumination fiber 53 .
[0064] The actions of the bending block 54 b pushing the side of the illumination fiber 53 is explained below. As shown in FIG. 8 , when the bending block 54 b bends in the second direction, a recessed section 54 s 1 of the supporting block 54 s that is positioned entirely within (does not protrude from) the bending block 54 b is pushed in the second direction.
[0065] The protruding section 54 s 2 of the supporting block 54 s does not bend in the second direction because the pushing force exerted by the bending block 54 b is not applied directly to the protruding section 54 s 2 of the supporting block 54 s. Accordingly, the protruding section 54 s 2 deforms elastically and bends in the opposite direction of the second direction. Afterward, a restoring force is applied to return the protruding section 54 s 2 toward the second direction.
[0066] The outside of the illumination fiber 53 is pushed by the restoring force applied to the protruding section 54 s 2 , which causes the illumination fiber 53 to bend along the second direction. The restoring force (see “e” in FIG. 9 ) is distributed across the entire protruding section 54 s 2 and exerted on the illumination fiber 53 .
[0067] If the supporting block 54 ′ s is made of solid material, as shown in FIG. 10 , a large force (see “E” in FIG. 10 ) is exerted on the end of the supporting block 54 ′ s where the supporting block 54 ′ s makes contact with the illumination fiber 53 . The large force applied to a narrow section of the illumination fiber 53 may cause damage to the illumination fiber 53 . On the other hand, in this embodiment damage of the illumination fiber 53 can be decreased by applying the restoring force distributed across the entire protruding section 54 s 2 .
[0068] As shown in FIG. 11 , the emission end of the illumination fiber 53 is moved so that the emission end vibrates along the second and third directions at amplitudes that are repetitively increased and decreased. The frequencies of the vibration along the second and third directions are adjusted to be equal. In addition, the period to increase and to decrease the amplitudes of the vibration along the second and third directions are synchronized. Further, phases of the vibration along the second and third directions are shifted by 90 degrees.
[0069] By vibrating the emission end of the illumination fiber 53 along the second and third directions as described above, the emission end traces the spiral course shown in FIG. 12 , and the observation area is scanned with the white laser beam.
[0070] The position of the emission end of the illumination fiber 53 when the illumination fiber 53 is not bent is defined as a standard point. While the emission end is vibrated with increasing amplitude starting from the standard point (see “scanning period” in FIG. 11 ), illumination of the observation area with the white laser beam and generation of pixel signals are carried out.
[0071] In addition, when the amplitude reaches a maximum among the predetermined range, one scanning operation for producing one image terminates. After termination of a scanning operation, the emission end of the illumination fiber 53 is returned to the standard point by vibrating the emission end with progressively decreasing amplitudes (see “braking period” in FIG. 11 ). When the emission end is returned to the standard point, it is the beginning of a scanning operation for generating another image.
[0072] The lens 56 is mounted in the emission direction in which light is emitted from the emission end that is positioned at the standard point (see FIG. 4 ). The lens 56 is fixed in the scanning endoscope 50 so that an optical axis of the lens 56 is parallel to the emission direction in which light is emitted from the emission end that is positioned at the standard point.
[0073] The white laser beam emitted from the illumination fiber 53 passes through the lens 56 before reaching an individual point within the observation area (see FIG. 13 ). The reflected light is scattered at that point. The scattered and reflected light is incident on the incident ends of the image fibers 55 .
[0074] A plurality of the image fibers 55 are mounted in the scanning endoscope 50 . The incident ends of the image fibers 55 are arranged around the lens 56 (see FIG. 13 ). The light that is scattered and reflected from the point in the observation area is incident on all the image fibers 55 .
[0075] The reflected light incident on the incident ends of the image fibers 55 is transmitted to the emission ends of the image fibers 55 . As described above, the emission ends of the image fibers 55 are optically connected to the light-capturing unit 21 . The reflected light transmitted to the emission ends is incident on the light-capturing unit 21 .
[0076] The light-capturing unit 21 detects the amounts of red, green, and blue light components in the reflected light, and generates pixel signals according to the amounts of the light components. The pixel signals are transmitted to the image-processing circuit 23 .
[0077] The image-processing circuit 23 estimates the points where the white laser beam is shined on the basis of signals used to control the scanning driver 22 . In addition, the image-processing circuit 23 stores the received pixel signals at the address of the image memory 26 that corresponds to the estimated points.
[0078] As described above, the observation area is scanned with the white laser beam, pixel signals are generated on the basis of the reflected light at the respective points illuminated with the white laser beam, and the generated pixel signals are stored at the addresses corresponding to the points. The image signal corresponding to the observation area comprises the pixel signals corresponding to the points from the scan-start point to the scan-end point. As described above, the image-processing circuit 23 carries out predetermined image processing on the image signal. After undergoing predetermined image processing, the image signal is transmitted to the monitor 11 .
[0079] In the above first embodiment, it is easy to accurately manufacture a scanning endoscope with illumination fiber 53 that can sufficiently withstand the pushing force exerted by the bending block 54 b.
[0080] In addition, in the above first embodiment, even if the fiber actuator 54 is exposed to a high ambient temperature, the fiber actuator 54 can still carry out a stable scanning operation, as explained below.
[0081] Although most of the light emitted from the emission end of the illumination fiber 53 passes through the lens 56 , a portion of the light is reflected by the lens 56 onto the supporting block 54 s. The supporting block 54 s will generate heat due to the reflected light striking it. Accordingly, unless the supporting block 54 s can maintain its shape without deformation when exposed to high ambient temperatures, the supporting block 54 s will become distorted and carrying out a stable scanning operation will not be possible. However, in the above first embodiment, the supporting block 54 s is made of metal, which provides sufficient protection against deformation caused by high ambient temperatures. Accordingly, even if the fiber actuator 54 is exposed to high ambient temperatures, the fiber actuator 54 can stably move the emission end of the illumination fiber 53 and a stable scanning operation can be carried out.
[0082] Next, a scanning endoscope of the second embodiment is explained. The primary difference between the second embodiment and the first embodiment is the shape of the supporting block. The second embodiment is explained mainly with reference to the structures that differ from those of the first embodiment. Here, the same index numbers are used for the structures that correspond to those of the first embodiment.
[0083] As shown in FIG. 14 , the supporting block 540 s is a metal coil spring configured so that the outside and inside diameters of the coil spring are substantially equal to the inside diameter of the cylindrical bending block 54 b and the outside diameter of the illumination fiber 53 , respectively, as in the first embodiment. However, the coil pitch of the protruding section 540 s 2 is not constant, unlike the first embodiment, and is relatively longer at the end nearest to the emission end of the illumination fiber 53 compared to the other end.
[0084] Owing to the above shape of the supporting block 540 s , the mass per a predetermined length along the axial direction of the coil is lower at the section with the longer respective coil pitch (see “L 1 ” in FIG. 14 ) than the mass of the section with the shorter coil pitch (see “L 2 ” in FIG. 14 ). Accordingly, the center of mass for the combination of the illumination fiber 53 and the protruding section 540 s 2 is relatively closer to the bending block 54 b. Owing to the shift in the center of mass, the resonant frequency of the section of the illumination fiber 53 that vibrates with the protruding section 540 s 2 is increased with the adjustment.
[0085] In the above second embodiment, the same effect can be achieved as in the first embodiment.
[0086] In addition, the resonant frequency of the section of the illumination fiber 53 that vibrates with the protruding section 540 s 2 can be adjusted to exceed the resonant frequency of the protruding section that has a constant coil pitch, unlike the first embodiment. In general, the illumination fiber 53 is oscillated at a frequency near the resonant frequency in order to achieve stable vibration. Accordingly, by adjusting the supporting block so that the resonant frequency increases, the illumination fiber 53 can be vibrated at a higher speed compared to the first embodiment.
[0087] In the prior art, the resonant frequency was adjusted by selecting a different material for the illumination fiber 53 , and/or changing the length of the section of the illumination fiber 53 protruding from the fiber actuator 54 . However, in the above second embodiment, the resonant frequency can be adjusted by changing the pitch of the coil and/or the position where the pitch of the coil changes, in addition to the above prior adjustment method.
[0088] Next, a scanning endoscope of the third embodiment is explained. The primary difference between the third embodiment and the first embodiment is the shape of the supporting block. The third embodiment is explained mainly with reference to the structures that differ from those of the first embodiment. Here, the same index numbers are used for the structures that correspond to those of the first embodiment.
[0089] As shown in FIG. 15 , the supporting block 541 s is a metal coil spring configured so that the outside and inside diameters of section of the coil spring are substantially equal to the inside diameter of the cylindrical bending block 54 b and the outside diameter of the illumination fiber 53 , respectively, as in the first embodiment. The supporting block 541 s is configured so that the diameter of the strand of the coil is not constant, with the protruding section 541 s 2 formed with a strand having a smaller diameter at the end nearest to the emission end of the illumination fiber 53 than at the other end, unlike the first embodiment.
[0090] Owing to the above shape of the supporting block 541 s , the mass per a predetermined length along the axial direction of the spring coil is lower at the section where the strand is thinner (see “L 3 ” in FIG. 15 ) than compared to the section where the strand is thicker (see “L 4 ” in FIG. 15 ). Accordingly, the center of mass for the combination of the illumination fiber 53 and the protruding section 541 s 2 is relatively closer to the bending block 54 b. Owing to the shift in the center of mass, the resonant frequency of the section of the illumination fiber 53 that vibrates with the protruding section 541 s 2 is increased with the adjustment.
[0091] In the above third embodiment, the same effect can be achieved as in the first embodiment. In addition, the resonant frequency of the section of the illumination fiber 53 that vibrates with the protruding section 541 s 2 can be adjusted to be greater than that of the protruding section where the diameter of the strand is constant, as in the second embodiment.
[0092] Next, a scanning endoscope of the fourth embodiment is explained. The primary difference between the fourth embodiment and the first embodiment is the shape of the supporting block. The fourth embodiment is explained mainly with reference to the structures that differ from those of the first embodiment. Here, the same index numbers are used for the structures that correspond to those of the first embodiment.
[0093] As shown in FIG. 16 , the supporting block 542 s is a metal coil spring that comprises a recessed section 542 s 1 and a protruding section 542 s 2 .
[0094] The protruding section 542 s 2 is configured so that the outside and inside diameter of the coil spring increases as the position along the axial direction is closer to the emission end of the illumination fiber 53 . In addition, the protruding section 542 s 2 is configured so that the distance between the centerline of the coil strand and the axial line of the supporting block increase gradually with positive convexity.
[0095] In addition, the recessed section 542 s 1 is configured so that the outside and inside diameter of the coil spring are substantially equal to the inside diameter of the cylindrical bending block 54 b and the outside diameter of the illumination fiber 53 , respectively.
[0096] Owing to the above shape of the supporting block 542 s , the durability of the illumination fiber 53 can be improved relative to the first embodiment. As described above, owing to the configuration of the supporting block 54 s as a coil spring, a restoring force is distributed across the entire side of the protruding section 54 s 2 .
[0097] However, even if the restoring force is broadly distributed, the distributed restoring forces are not equal for each point where the illumination fiber 53 and the supporting block 54 s make contact, and the restoring forces become greater the closer they are to the end of the supporting block 54 s that is closest to the emission end of the illumination fiber 53 (see in FIG. 17 ). Accordingly, the greatest force among the distributed restoring forces is exerted on the illumination fiber 53 at the end of the supporting block 54 s. On the other hand, in the above fourth embodiment, the illumination fiber 53 is bent along the inside surface of the protruding section 542 s 2 , where the inside diameter gradually spreads from the recessed section 542 s 1 to the end, and the restoring force exerted on the illumination fiber 53 is distributed more equally than in the first embodiment (see FIG. 18 ).
[0098] In the above fourth embodiment, the same effect can be achieved as in the first embodiment. In addition, the durability of the illumination fiber 53 can be improved with respect to the first embodiment.
[0099] Next, a scanning endoscope of the fifth embodiment is explained. The primary difference between the fifth embodiment and the first embodiment is the shape of the supporting block. The fifth embodiment is explained mainly with reference to the structures that differ from those of the first embodiment. Here, the same index numbers are used for the structures that correspond to those of the first embodiment.
[0100] As shown in FIGS. 19 and 20 , the supporting block 543 s comprises a plurality of metal rods bundled together to form a cylinder around the illumination fiber 53 . The metal rods have adequate elasticity. Accordingly, the metal rods can work the same as the coil spring in the first embodiment when the bending block 54 b bends the illumination fiber 53 . The illumination fiber 53 is positioned inside of the cylindrical supporting block 543 s . The illumination fiber 53 is supported by the supporting block 543 s as the emission end of the illumination fiber 53 protrudes from the supporting block 543 s, as in the first embodiment.
[0101] In addition, a portion of the supporting block 543 s is fixed inside of the cylindrical bending block 54 b, as in the first embodiment. Accordingly, the supporting block 543 s is positioned between the bending block 54 b and the illumination fiber 53 , as in the first embodiment.
[0102] In the above fifth embodiment, the same effect can be achieved as in the first embodiment.
[0103] Next, a scanning endoscope of the sixth embodiment is explained. The primary difference between the sixth embodiment and the fifth embodiment is the shape of the supporting block. The sixth embodiment is explained mainly with reference to the structures that differ from those of the fifth embodiment. Here, the same index numbers are used for the structures that correspond to those of the first embodiment.
[0104] As shown in FIG. 21 , the supporting block 544 s comprises a plurality of metal rods bundled together to form a cylinder around the illumination fiber 53 , as in the fifth embodiment. The rods that constitute the supporting block 544 s are configured so that their thickness in the protruding section 544 s 2 tapers off and their diameter decreases toward the end corresponding to the emission end of the illumination fiber 53 , unlike in the fifth embodiment. Accordingly, a cross-sectional area of the protruding section 544 s 2 perpendicular to the longitudinal direction of the protruding section 544 s 2 varies according to a position of the protruding section 544 s 2 along the first direction.
[0105] Owing to the above shape of the supporting block 544 s , the mass per a predetermined length along the axial direction of the tapered section of the supporting block 544 s (see “L 5 ” in FIG. 21 ) is lower than that of the non-tapered, constant thickness section (see “L 6 ” in FIG. 21 ). Accordingly, the center of mass for the combination of the illumination fiber 53 and the protruding section 544 s 2 is relatively closer to the bending block 54 b. Owing to the shift in the center of mass, the resonant frequency of the section of the illumination fiber 53 vibrating with the protruding section 544 s 2 is increased with the adjustment.
[0106] In the above sixth embodiment, the same effect can be achieved as in the fifth embodiment. In addition, in the above sixth embodiment, the resonant frequency of the section of the illumination fiber 53 that vibrates with the protruding section 544 s 2 can be adjusted to be greater than that of the non-tapered, constant thickness rods constituting the supporting block, as in the second and third embodiments.
[0107] Next, a scanning endoscope of the seventh embodiment is explained. The primary difference between the seventh embodiment and the fifth embodiment is the shape of the supporting block. The seventh embodiment is explained mainly with reference to the structures that differ from those of the fifth embodiment. Here, the same index numbers are used for the structures that correspond to those of the first embodiment.
[0108] As shown in FIG. 22 , the supporting block 545 s comprises a plurality of metal rods bundled together to form a cylinder around the illumination fiber 53 . The metal rods are configured to have the recessed section 545 s 1 and the protruding section 545 s 2 as one body. The recessed section 545 s 1 is formed to be straight. The protruding section 545 s 2 is funnel-shaped with a curved surface. In addition, the narrowest end of the protruding section 545 s 2 is connected to the recessed section 545 s 1 to form one body. In addition, the protruding section 545 s 2 is formed so that the distance between the inside surface and the axial line of the supporting block 545 s increases with positive convexity as the point on the axial line moves further from the recessed section 545 s 1 . One end of the supporting block 545 s is positioned inside the bending block 54 b.
[0109] In the above seventh embodiment, the same effect can be achieved as in the fifth embodiment. In addition, in the above seventh embodiment, as in the fourth embodiment, the durability of the illumination fiber 53 can be improved with respect to the fifth embodiment.
[0110] The supporting blocks 54 s, 540 s, 541 s, 542 s, 543 s , 544 s, and 545 s comprise either a coil spring or elastic metal rods in the above first-seventh embodiments. However, other springs or elastic materials can constitute the supporting block. The same effect can be achieved as that in the first-seventh embodiments as long as the supporting block can deform elastically and transmit the restoring force to the side of the illumination fiber 53 .
[0111] The fiber actuator 54 b bends the illumination fiber 53 in four directions, which are the positive and negative components of the second and third directions, in the above first-seventh embodiments. However, the fiber actuator 54 b may bend the illumination fiber 53 in any, but at least one, direction.
[0112] The supporting blocks 54 s, 540 s, 541 s, 542 s, 543 s , 544 s, and 545 s are made of metal material in the above first-seventh embodiments. However, the supporting block can be made of another material that provides sufficient protection against deformation caused by high ambient temperatures. Or, the supporting block does not have to be made of such kind of material. Even if the supporting block does not provide sufficient protection against deformation at high ambient temperatures, a scanning endoscope can still be accurately manufactured with an illumination fiber 53 that can sufficiently withstand the pushing force exerted by the bending block 54 b as in the first-seventh embodiments.
[0113] The supporting blocks 54 s, 540 s, 541 s, 542 s, 543 s , 544 s, and 545 s protrude from the bending block 54 b in the first-seventh embodiments. However, the supporting block may not be protruding. Even if the supporting block is not protruding, the same effect can be achieved as in the first-seventh embodiments as long as the supporting block deforms elastically and transmits the restoring force to the side of the illumination fiber 53 .
[0114] The metal rods that constitute the supporting block 543 s, 544 s, and 545 s are bundled together to forma complete circle around the illumination fiber 53 , in the fifth-seventh embodiments. However, a minimum number of metal rods may be mounted in the direction for bending the illumination fiber 53 . In the fifth-seventh embodiments, the illumination fiber 53 is bent in every combination of positive and negative second and third direction. If the illumination fiber 53 is bent in only one specific direction, the same effect can be achieved as in the fifth-seventh embodiments as long as the metal rod is mounted in the specific direction from the illumination fiber 53 .
[0115] The center of mass for the combination of the illumination fiber 53 and the protruding section 540 s 2 , 541 s 2 , and 542 s 2 is adjusted toward the bending block 54 b in the above second, third, and sixth embodiments. However, the position of the center of mass can be adjusted toward the emission end of the illumination fiber 53 .
[0116] As shown in FIG. 23 , the center of mass can be shifted toward the emission end of the illumination fiber 53 by forming the supporting block so that the coil pitch of the protruding section 546 s 2 is longer in the section nearest to the bending block 54 b than the section corresponding to the side nearest to the emission end of the illumination fiber 53 . By shifting the center of mass toward the emission end, the resonant frequency of the section of the illumination fiber 53 that vibrates with the protruding section can be reduced so that the illumination fiber 53 vibrates at a lower speed.
[0117] In addition, as shown in FIG. 24 , the center of mass can be shifted toward the emission end of the illumination fiber 53 by configuring the supporting block so that the diameter of the strand of the protruding section 547 s 2 tapers off and is smallest at the end nearest to the bending block 54 b.
[0118] In addition, as shown in FIG. 25 , the center of mass can be shifted toward the emission end of the illumination fiber 53 by configuring the supporting block so that the thickness of the rods that constitute the supporting block in the protruding section 548 s 2 tapers off and the rods become thinner toward the bending block 54 b.
[0119] As described above, the center of mass is adjustable by changing the mass per a predetermined length along a longitudinal direction of the supporting block.
[0120] The supporting blocks 543 s, 544 s, and 545 s comprise a plurality of metal rods in the fifth-seventh embodiments. However, the supporting block can comprise a plurality of flat springs.
[0121] The fiber actuator 54 moves the illumination fiber 53 so that the emission end of the illumination fiber 53 traces the predetermined spiral course, in the above first-seventh embodiments. However, the course to be traced is not limited to a spiral course. The illumination fiber 53 can be moved so that the emission end traces other predetermined courses.
[0122] Although the embodiments of the present invention have been described herein with reference to the accompanying drawings, obviously many modifications and changes may be made by those skilled in this art without departing from the scope of the invention.
[0123] The present disclosure relates to subject matter contained in Japanese Patent Application No. 2009-005109 (filed on Jan. 13, 2009), which is expressly incorporated herein, by reference, in its entirety. | A scanning endoscope comprising a light transmitter, an actuator, and a force transmitter, is provided. The light transmitter emits a beam of the light exiting the first emission end. The light transmitter is flexible. A longitudinal direction of the light transmitter is a first direction. The actuator is mounted near the first emission end. The actuator bends the light transmitter in a second direction by pushing a side of the light transmitter in the second direction. The second direction is perpendicular to the first direction. A force transmitter is oriented lengthwise in the first direction. The force transmitter is elastic. The force transmitter is positioned between the light transmitter and the actuator. The force transmitter exerts a pushing force supplied by the actuator on the side of the light transmitter while the force transmitter is deformed elastically toward the first direction. | 0 |
BACKGROUND
[0001] This invention relates generally to gas turbine engines, and more particularly, to a system and method for extracting and using heat from a gas turbine's intercooler in a steam cycle.
[0002] Gas turbine engines generally include, in serial flow arrangement, a high-pressure compressor for compressing air flowing through the engine, a combustor in which fuel is mixed with the compressed air and ignited to form a high temperature gas stream, and a high-pressure turbine. The high-pressure compressor, combustor and high-pressure turbine are sometime collectively referred to as the core engine. At least some known gas turbine engines also include a low-pressure compressor, or booster, for supplying compressed air to the high pressure compressor.
[0003] Gas turbine engines are used in many applications, including aircraft, power generation, and marine applications. The desired engine operating characteristics vary, of course, from application to application. More particularly, within some applications, a gas turbine engine may include a single annular combustor, including a water injection system that facilitates reducing nitrogen oxide (NOx) emissions. Alternatively, within other known application, the gas turbine engine may include a dry low emission (DLE) combustor.
[0004] Gas turbines alone have a limited efficiency and a significant amount of useful energy is wasted as hot exhaust gas is discharged to the ambient. To improve the efficiency of a gas turbine power plant and use this heat for further power generation, many gas turbines are equipped with a heat recovery steam generator and a steam cycle. This is known as a combined cycle.
[0005] Inter-cooled gas turbine engines may include a combustor that may be a single annular combustor, a can-annular combustor, or a DLE combustor. While using an intercooler facilitates increasing the efficiency of the engine, the heat rejected by the intercooler is not utilized by the gas turbine engine, and the intercooler heat from an intercooled gas turbine or compressor is usually wasted. In some applications, a cooling tower discharges intercooler heat to the ambient at a low temperature level.
[0006] There is a need for a system and method for extracting and using heat from a gas turbine's intercooler in a steam cycle.
BRIEF DESCRIPTION
[0007] According to one embodiment, a combined gas and steam turbine power plant comprises:
[0008] a gas turbine;
[0009] a gas turbine intercooler;
[0010] a steam turbine; and
[0011] a heat recovery steam generator (HRSG) configured to generate steam for driving the steam turbine in response to heated fluid received from the gas turbine intercooler.
[0012] According to another embodiment, a combined gas and steam turbine power plant comprises:
[0013] a gas turbine;
[0014] a gas turbine intercooler;
[0015] a steam turbine; and
[0016] a heat recovery steam generator (HRSG) connected downstream from a low-pressure gas turbine compressor and upstream from a high-pressure gas turbine compressor in a steam cycle, wherein the HRSG is configured to generate steam for driving the steam turbine in response to a heat transfer medium received via the gas turbine intercooler.
[0017] According to yet another embodiment, combined gas and steam turbine power plant comprises:
[0018] a gas turbine;
[0019] a gas turbine intercooler;
[0020] a steam turbine; and
[0021] a heat recovery steam generator (HRSG),
[0000] wherein the gas turbine intercooler is configured to recover the intercooling heat and use substantially all of the recovered heat to produce hot water and steam for driving the steam turbine.
DRAWINGS
[0022] These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawing, wherein:
[0023] FIG. 1 is a block diagram of a gas turbine engine including an intercooler system; and
[0024] FIG. 2 illustrates a combined cycle power plant according to one embodiment.
[0025] While the above-identified drawing figures set forth particular embodiments, other embodiments of the present invention are also contemplated, as noted in the discussion. In all cases, this disclosure presents illustrated embodiments of the present invention by way of representation and not limitation. Numerous other modifications and embodiments can be devised by those skilled in the art which fall within the scope and spirit of the principles of this invention.
DETAILED DESCRIPTION
[0026] FIG. 1 is a block diagram of a gas turbine engine 10 including an intercooler system 12 . Gas turbine engine 10 includes, in serial flow relationship, a low pressure compressor or booster 14 , a high pressure compressor 16 , a can-annular combustor 18 , a high-pressure turbine 20 , an intermediate turbine 22 , and a power turbine or free turbine 24 . Low-pressure compressor or booster 14 has an inlet 26 and an outlet 28 , and high-pressure compressor 16 includes an inlet 30 and an outlet 32 . Each combustor can 18 has an inlet 34 that is substantially coincident with high-pressure compressor outlet 32 , and an outlet 36 . In another embodiment, combustor 18 is an annular combustor. In another embodiment, combustor 18 is a dry low emissions (DLE) combustor.
[0027] High-pressure turbine 20 is coupled to high-pressure compressor 16 with a first rotor shaft 40 , and intermediate turbine 22 is coupled to low pressure compressor 14 with a second rotor shaft 42 . Rotor shafts 40 and 42 are each substantially coaxially aligned with respect to a longitudinal centerline axis 43 of engine 10 . Engine 10 may be used to drive a load (not shown) which may be coupled to a power turbine shaft 44 . Alternatively, the load may be coupled to a forward extension (not shown) of rotor shaft 42 .
[0028] In operation, ambient air, drawn into low-pressure compressor inlet 26 , is compressed and channeled downstream to high-pressure compressor 16 . High-pressure compressor 16 further compresses the air and delivers high-pressure air to combustor 18 where it is mixed with fuel, and the mixture is ignited to generate high temperature combustion gases. The combustion gases are channeled from combustor 18 to drive one or more turbines 20 , 22 , and 24 .
[0029] The power output of engine 10 is at least partially related to operating temperatures of the gas flow at various locations along the gas flow path. More specifically, in the exemplary embodiment, an operating temperature of the gas flow at high-pressure compressor outlet 32 is closely monitored during the operation of engine 10 . Reducing an operating temperature of the gas flow entering high-pressure compressor 16 facilitates decreasing the power input required by high-pressure compressor 16 .
[0030] To facilitate reducing the operating temperature of a gas flow entering high-pressure compressor 16 , intercooler system 12 includes an intercooler 50 that is coupled in flow communication to low pressure compressor 14 . Airflow 53 from low-pressure compressor 14 is channeled to intercooler 50 for cooling prior to the cooled air 55 being returned to high-pressure compressor 16 .
[0031] During operation, intercooler 50 has a cooling fluid 58 flowing therethrough for removing energy extracted from the gas flow path. In one embodiment, cooling fluid 58 is air, and intercooler 50 is an air-to-air heat exchanger. In another embodiment, cooling fluid 58 is water, and intercooler 50 is an air-to-water heat exchanger. Intercooler 50 extracts heat energy from compressed air flow path 53 and channels cooled compressed air 55 to high-pressure compressor 16 . More specifically, in the exemplary embodiment, intercooler 50 includes a plurality of tubes (not shown) through which cooling fluid 58 circulates. Heat is transferred from compressed air 53 through a plurality of tube walls (not shown) to cooling fluid 58 supplied to intercooler 50 through inlet 60 . Accordingly, intercooler 50 facilitates rejecting heat between low-pressure compressor 14 and high-pressure compressor 16 . Reducing a temperature of air entering high-pressure compressor 16 facilitates reducing the energy expended by high-pressure compressor 16 to compress the air to the desired operating pressures, and thereby facilitates allowing a designer to increase the pressure ratio of the gas turbine engine which results in an increase in energy extracted from gas turbine engine 10 and a high net operating efficiency of gas turbine 10 .
[0032] In an exemplary embodiment, feedwater is flowing through intercooler 50 for removing energy extracted from gas flow path 53 and functions as the cooling fluid 58 . The feedwater is being heated or turned into low-pressure (LP) steam, or a combination thereof as described in further detail herein. In this fashion, the extracted heat, if extracted at a higher temperature, ideally approaching that of the hot compressed inlet air, can be a useful contributor to a bottoming cycle generating electricity.
[0033] Whether feedwater heating only or steam generation is preferable depends on the bottoming cycle configuration, required feedwater mass flows and intercooler temperatures. Exergy considerations suggest that intermediate or high-pressure feedwater heating can yield the highest available work from the intercooler heat; however, the amount of feedwater to be heated may be more than the bottoming cycle requires and may compete with HRSG economizers. Low-pressure preheating and steam generation is the alternative. The exergy portion can be more than twenty (20) % of the available intercooler heat under typical conditions.
[0034] Intercooler 50 may comprise a high efficiency counterflow or cross-counterflow heat exchanger to gain useful heat from intercooling air with feedwater applications. One suitable configuration may include, for example, a serpentine coil fin-tube heat exchanger enclosed within a pressure shell.
[0035] According to one aspect, intercooler 50 may be used to generate hot feedwater or saturated steam by utilizing a significant fraction of the available heat from the hot air in a suitable heat exchanger. This hot feedwater or saturated steam, at low-pressure to facilitate evaporation at temperatures as low as about 100° C., is fed into an evaporator (if hot feedwater) or a superheater (if saturated steam) in a heat recovery steam generator (HRSG) described in further detail herein with reference to FIG. 2 , and admitted to a low-pressure turbine, also described in further detail herein. The extra steam then generates additional electricity.
[0036] FIG. 2 illustrates a combined cycle power plant 100 according to one embodiment. The power plant 100 comprises a high pressure gas turbine system 10 with a combustion system 18 and a turbine 20 . The gas exiting turbine 20 may be at a pressure, for example, of about 45 psi for one particular application. The power plant 100 further comprises a steam turbine system 110 . The steam turbine system 110 comprises a high pressure section 112 , an intermediate pressure section 114 , and one or more low pressure sections 116 . The low pressure section 116 exhausts into a condenser 120 .
[0037] The steam turbine system 100 is associated with a heat recovery steam generator (HRSG) 104 . According to one embodiment, the HRSG 104 is a counter flow heat exchanger such that as feedwater passes there through, the water is heated as the exhaust gas from turbine 16 gives up heat and becomes cooler. The HRSG 104 has three (3) different operating pressures (high, intermediate, and low) with means for generating steam at the various pressures and temperatures as vapor feed to the corresponding stages of the steam turbine system 110 . The present invention is not so limited however; and it can be appreciated that other embodiments, such as those embodiments comprising a two-pressure HRSG will also work using the principles described herein. Each section of the HRSG 104 generally comprises one or more economizers, evaporators, and superheaters.
[0038] The HRSG 104 uses the heat of the turbine 20 exhaust gas to produce three (3) steam streams, a high pressure steam stream 128 , an intermediate pressure stream 130 , and a low pressure steam stream 132 . These three steam streams enter the high, intermediate and low pressure steam turbines 112 , 114 , 116 to produce power. A high pressure steam stream extracted from the high pressure steam turbine 112 is injected to the gas turbine combustor 18 .
[0039] Subsequent to exiting the low pressure steam turbine 116 , the steam stream enters the condenser 120 where the steam is condensed into liquid water. The liquid water exiting the condenser 120 along with make-up water 122 and residual water from the HRSG 104 enters a water collector 124 .
[0040] An appropriate amount of water is pumped from the water collector 124 to the HRSG 104 where the water absorbs the heat from the high pressure gas turbine exhaust to generate the requisite steam streams. The three steam streams enter the steam turbines 112 , 114 , 116 to complete the bottoming cycle.
[0041] According to one embodiment, combined cycle power plant 100 further comprises a gas turbine intercooler 50 that operates as described herein before with reference to FIG. 1 . Intercooler 50 may comprise, for example, a high efficiency counterflow or cross-counterflow heat exchanger as stated herein, to generate hot feedwater or saturated steam 126 by utilizing a significant fraction of the available heat from the hot air stream 53 . This hot feedwater or saturated steam 126 , at low pressure to facilitate evaporation at temperatures as low as about 100° C., is fed into an evaporator (if hot feedwater) or a superheater (if saturated steam) in the HRSG 104 , and subsequently admitted to the low-pressure turbine 116 . The extra steam then generates additional electricity, as stated herein. In this way, system efficiency is advantageously increased while simultaneously decreasing the size of the cooling system.
[0042] In summary explanation, a system and method have been described herein for harvesting a significant amount of intercooler heat and generating additional electricity therefrom in a gas turbine bottoming cycle, thus substantially eliminating wasted heat. Since the heat is integrated into the bottoming cycle in the form of steam hot feedwater, no major additional investment is required. The present inventors recognized the foregoing advantages even though intercooler heat has been rarely employed due to the corresponding low temperature(s) and regardless of the low numbers of large gas turbines that employ intercoolers.
[0043] While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims. | A steam cycle power plant includes a gas turbine, a gas turbine intercooler, a steam turbine, and a heat recovery steam generator (HRSG). The gas turbine intercooler recovers unused heat generated via the gas turbine and transfers substantially all of the recovered heat for generating extra steam for driving the steam turbine. | 5 |
COPYRIGHT NOTICE
A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
The claimed invention relates generally to a network, and more particularly, to a gaming network.
In early gaming environments, gaming machines were stand-alone devices. Security of the gaming machines was accomplished via physical locks, security protocols, security personnel, physical and video monitoring, and the need to be physically present at a machine to attempt to breach the security of the gaming machine. By the same token, management of the gaming machines required a great deal of personal physical interaction with each gaming machine. The ability to change parameters of the gaming machine also required physical interaction.
In view of the increased processing power and availability of computing devices, gaming machines have become customizable via electronic communications and remotely controllable. Manufacturers of gaming equipment have taken advantage of the increased functionality of gaming machines by adding additional features to gaming machines, thereby maintaining a player's attention to the gaming machines for longer periods of time increasing minimum bet and bet frequency and speed of play. This, in turn, leads to the player wagering at the gaming machine for longer periods of time, with more money at a faster pace, thereby increasing owner profits.
One technique that has been employed to maintain a player's attention at the gaming machine has been to provide players with access to gambling-related information. In this regard, attaching a small electronic display to the gaming device, gambling-related information, as well as news and advertisements can be sent to the player. The gambling-related information may include, for example, information on sports betting and betting options for those sporting events. Additionally, the gambling-related information may also include information such as horse racing and off-track betting. News and advertisements can also maintain a player's attention by providing the player with access to information ranging from show times, to restaurant and hotel specials, and to world events, thus reducing the need and/or desire of the player to leave the gaming machine.
Moreover, it has been shown to be desirable to provide the player with interactive access to the above information. This type of interactivity allows players significantly more flexibility to make use of the above-described information. The gambling-related information can also be utilized by the player in a much more efficient manner. In this regard, greater levels of flexibility and access are likely to make the player remain and gamble at the gaming machine for significantly longer periods of time.
In addition, the player may participate in a “premium” promotion where the player is registered with the gaming establishment as a club member when the player inserts an ID card into the gaming machines during play. The player may be rewarded for certain play patterns (e.g. wager amounts, wager totals, payouts, time of play, or the like) and earn redeemable benefits or upgrade of club member status.
Attempts to distribute gambling-related information and advertisements to players and to allow the recognition of premium membership players have resulted in additional system components that may be attached to the gaming devices. These components for accessing and displaying information for gaming machines may include a keypad, card reader, and display equipment.
The amount of interactivity and data presentation/collection possible with current processor based gaming machines has led to a desire to connect gaming machines in a gaming network. Current networks for gaming machines have been primarily one-way in communication, have been slow, and have been proprietary (custom designed and incompatible with commercial networking equipment). Prior art networks provided accounting, security, and player related data reporting from the gaming machine to a backend server. Secondary auditing procedures allowed regulators and managers to double check network reporting, providing a method of detecting malfeasance and network attacks. However, such security is remote in time from when a network attack has occurred. Prior art networks lack many security features needed for more rapid detection of cheating from a variety of possible attackers.
Although prior art networks of gaming machines provide advantages to gaming establishment operators, they also engender new risks to security of the gaming establishment and to the gaming machines. Not only is traditional data associated with gaming machines now potentially at risk on the gaming network, but personal player information is now at risk, as well.
In addition, the proprietary nature of prior art gaming machine networks limits the ability to use commercially available technology, This adds to the cost of gaming networks and limits their scalability and the ability to upgrade as technology improves. Further, as gaming machines are grouped in networks, the value of the pooled financial data traversing the network creates a great temptation to attack the network. The potential reward from attacking a network of gaming machines is greater than the reward from attacking a single machine.
Attempts to illicitly obtain access to the gaming network are referred to as network attacks. These attacks can be driven by different motivations and are characterized by the type of attack involved. In addition, attackers can be either insiders (gaming establishment employees, regulators, security personnel) or outsiders. FIG. 7 illustrates possible attacks on a network. The gaming network 701 may be attacked by an insider 703 . Insiders include casino employees, regulators, game manufacturers, game designers, network administrators, etc. Outsiders 704 might also attack the network 701 . Outsiders may include hackers with an IP connection attacking the network and/or devices (including games) on the network. The network may be attacked via a bridge 702 to the Internet. Examples of attacks are described below.
Attack Motivation
Typical motivations for attack on a gaming network include the desire to steal money or to embarrass or blackmail an entity. For example, an attacker may attempt to steal money from the gaming establishment, from a patron or player, or from a regulatory or other political body (e.g., a state that taxes gaming revenue). The attempt to steal may involve attempts to artificially manipulate wagers or payouts to the attacker's benefit. An attacker may also attempt to obtain credit or other personal information from the network that can be used to illicitly obtain money. Other attackers (typically insiders) may wish to manipulate accounting data to defraud government agencies by underreporting taxable revenue. An attacker may attempt to collect gaming habit or other sensitive information regarding a patron as a blackmail threat, or the attacker may attempt to embarrass or blackmail the gaming establishment, the gaming machine manufacturer, a regulating agency, or a political organization by showing the vulnerability of the network to attack. Instead of taking money directly, an attacker may attempt to manipulate a network so that a gaming establishment loses money to players.
Attack Types
Attackers may attempt one or more direct attacks against the network, attacks against hosts, physical attacks, or other types of attacks. Attacks against the network may include attempts to obtain plaintext network traffic, forging network traffic, and denying network services.
Consequently, there are a number of methods of attack to obtain plaintext traffic. An attacker may eavesdrop (e.g., electronically) on unprotected traffic. The plaintext messages may be openly accessed or inferred via message and traffic analysis. Eavesdropping may be accomplished by illicitly controlling a device that is a legitimate part of the network or by re-routing network traffic to the attacker's own device.
Furthermore, if the attacker has access to the network and can mimic network protocols, the attacker may forge network traffic so that malicious messages are routed as legitimate messages. Such malicious messages can affect game play, send false financial transactions, reconfigure network administration, and/or disable security features to permit other forms of attack, or to hide current attacks. This type of attack may also include repeating legitimate messages for malicious purposes, such as repeating a password message to gain access to the privileges associated with that password, playing back a cash withdrawal request, a winning game play message, or a jackpot won event.
Still further, “denial of service” attacks are a notorious method of attacking a network or server. Such attacks often consist of flooding the network with bogus messages, therefore blocking, delaying, or redirecting traffic. The saturation of the network at the devices, servers, IP ports, or the like, can prevent normal operation of the network, especially for those network services that are time sensitive.
Moreover, an attacker may also use the network to attack a host or to attack the host directly via a local console. This is accomplished by attacking vulnerable, exposed, and/or unprotected IP ports, or via a “worm” transmitted via email, for example. In this way, malicious code can be introduced into the network to open the door for later attacks and to mask this and other attacks.
In addition, physical attacks on the network devices may also be a goal of an attacker. The devices, hosts, servers, and consoles should all have physical protection and security to prevent access by outsiders or by unauthorized insiders. Devices requiring such protection may include game machines, network cables, routers, switches, game servers, accounting servers, and network security components including firewalls and intrusion detection systems.
Other attacks may include attacks on the encryption/certification system. An attacker may attempt to compromise or to obtain the private key (e.g. of an operator or a manufacturer) of a public key infrastructure. Alternatively, the attacker may compromise the certifying authority of the network owner. Other schemes may include reinstalling older, but legitimate versions of software (recognized by the system as legitimate) the older version not being updated for corrected security flaws. Bridging a secure network to another network may also be attempted.
In some cases, the regulatory jurisdiction may have its own encryption key. This may be another type of inside attack that may be made. Someone in the regulatory jurisdiction may attempt to move or spoof data on the network for one or more of the purposes described above.
Accordingly, a gaming network requires robust protection against attacks from insiders and outsiders using a variety of attack methods.
SUMMARY OF THE INVENTION
Briefly, and in general terms, the gaming network described herein includes network security features, host security features, audit protocols, and design architecture approaches to reduce the possibility and success of network attacks. More particularly, the gaming network provides for traffic confidentiality, encryption, message authentication, secure authentication mechanisms, anti-replay protection of traffic, key management mechanisms, robust network availability, misrouting and redirection protection and prevention, rejection of external traffic, and a high entry barrier to device addition to the network.
The host protection and security aspects include secure host initialization, disabling unneeded components, download verification, disabling of unused IP ports, discarding traffic, strong passwords, dynamic one time passwords for remote login, disabling default accounts, and appropriate “least-level” device privileges.
Audit requirements include integrity protection of audit logs, appropriate definition of auditable events, auditing of anomalous behavior, chain of evidence preservation, shutdown if audit disabled, full log entry audits, personal ID and time access audit trails, and auditing of internal user actions.
In one embodiment of the gaming network, a host and a network device authenticate themselves to each other on the gaming network and generate a first security association. The host and the network device, which may be a gaming machine, use the first security association to generate a second security association for use in protecting message traffic on the gaming network. Each message has a certain minimum level of protection, provided by encryption in one embodiment, while still permitting additional security measures to be implemented in transactions between devices on the gaming network. In another embodiment, the negotiation used to authenticate a device to a host is the Internet Key Exchange (IKE) protocol phase I. In yet another embodiment, the protection of message traffic on the gaming network is accomplished by IKE protocol phase II.
In another embodiment, the gaming network comprises a core layer with a host server and switches, a distribution layer with managed routers and switches, and an access layer that includes managed switches and game machines. In another embodiment, the gaming network includes intrusion detectors to monitor attempts to attack the network. In yet another embodiment, the gaming network includes automatic disabling of any device where an intrusion attempt is detected by the intrusion detector. Similarly, in yet another embodiment, the gaming establishment system maps the association of legitimate IP addresses with device MAC addresses, unique device ID's (DID) and treats any alteration of any IP/MAC/DID association as an intrusion attempt. In still another embodiment, the gaming network uses private network IP addresses for network members. In another embodiment, the gaming network implements a virtual private network protocol.
These and other features and advantages of the claimed invention will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, which illustrate, by way of example, the features of the claimed invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of an embodiment of functional layers of a gaming network.
FIG. 2 is a block diagram of an embodiment of a gaming network.
FIG. 3 is a flow diagram of initialization of a network device in an embodiment of a gaming network.
FIG. 4 is a flow diagram of traffic authentication in an embodiment of a gaming network.
FIG. 5 is a flow diagram of an attack detection protocol in an embodiment of a gaming network.
FIG. 6 is a flow diagram illustrating a network device initialization sequence in an embodiment of the gaming network.
FIG. 7 is a block diagram illustrating examples of possible network attacks.
DETAILED DESCRIPTION
The claimed invention is directed to a gaming network. The preferred embodiments of the system and method are illustrated and described herein, by way of example only, and not by way of limitation.
The gaming network described herein proposes an architecture and system that provides an appropriate level of security from network attack. There exist techniques to authenticate and verify individual messages or activities in existing gaming establishment networks relying on proprietary protocols, transport and message formats. However, the gaming network described herein provides additional protection to the network itself particularly when use of commercially based IP equipment is envisioned, above and beyond particular security protocols, for activities and transactions carried on the network. The gaming network is independent of, and in addition to, security techniques for particular transactions or activities.
Referring now to the drawings, wherein like reference numerals denote like or corresponding parts throughout the drawings and, more particularly to FIGS. 1-7 , there is shown one embodiment of the gaming network constructed in accordance with the claimed invention. As shown in FIG. 1 , the network includes a core layer 101 over a distribution layer 102 above an access layer 103 . The core layer 101 serves as a gateway between servers and the gaming devices. The core layer 101 is contemplated to be a so-called “back end” layer that resides in an administrative location, separate from the gaming floor, for example, and protected physically and electronically.
The distribution layer 102 serves to collect traffic between the core layer 101 and the access layer 103 . The distribution layer may comprise trunks and switches that route message and signal traffic through the network. The access layer 103 provides a physical interface between the gaming machines (and any of their associated devices) and the rest of the network. This is done via managed switches.
One embodiment of a network using the layered scheme of FIG. 1 is illustrated in FIG. 2 . The core layer 101 includes one or more servers 201 that are coupled via a communication path 202 to one or more switches 203 . In one embodiment, the servers and switches of the core layer 101 are located within the gaming establishment premises in a secure administrative area. The servers 201 may, but are not required to be, game servers. The communication path 202 may be hardwire (e.g., copper), fiber, wireless, microwave, or any other suitable communication path that may be protected from attack. In one embodiment, the switches 203 are L2/L3 switches. However, one of ordinary skill in the art will appreciate that other types of switches may be used without departing from the scope or spirit of the claimed invention.
The distribution layer 102 communicates with the core layer 101 via high bandwidth communications links 204 . These links may be copper, fiber, or any other suitable link. If desired, redundant links 205 may be built into the system to provide more failsafe operation. The communications links couple the core layer switches 203 to the distribution layer switches 206 . These may be one or more switches, such as L2 switches, for example.
The distribution layer 102 communicates with the access layer 103 via a high capacity communication link 207 . The link 207 may be wire, fiber, wireless, or any other suitable communication link. In the embodiment of FIG. 2 , the communication link 207 is coupled to a gaming carousel 208 that comprises a plurality of gaming machines (e.g., 16 gaming machines 215 A- 215 P). A managed switch 209 is coupled to the link 207 to provide an interface switch to a plurality of other managed switches 210 through 213 . In the embodiment illustrated, each of the managed switches 210 - 213 manages four game machines 215 ( x ). It is understood that the types of switches may be changed without departing from the scope of the claimed invention. Further, switches with more or fewer ports may be substituted and more or fewer tiers of switches in the access layer may be used, as well, without departing from the scope or spirit of the claimed invention. In another embodiment, each game machine has its own managed switch.
In one embodiment of the gaming network, the network uses TCP/IP sessions between the gaming machines 215 and the servers 201 . The TCP/IP sessions are used to exchange private information concerning game operations, game performance, network management, patron information, revised game code, accounting information, configuration and download, and other sensitive information. In one embodiment, sessions may be a single message and acknowledgement, or the sessions may be an extended interactive, multiple transaction session. Other instantiations may include UDP/IP, token ring, MQ, etc.
In one embodiment of the gaming network, intrusion detectors provide additional security. In this regard, there may be intrusion detectors located between each layer, such as intrusion detector 220 located between the core layer 101 and the distribution layer 102 , and the intrusion detector 221 located between the distribution layer 102 and the access layer 103 . In addition, certain sensitive locations or choke points may include intrusion detectors such as the intrusion detector 223 coupled to the switch 209 . The intrusion detector 223 may disable the individual ports of switch 209 to isolate attacks while permitting continued operation of the remainder of the gaming network.
Moreover, the gaming network may use a number of network services for administration and operation. Dynamic Host Configuration Protocol (DHCP) allows central management and assignment of IP addresses within the gaming network. The dynamic assignment of IP addresses is used in one embodiment instead of statically assigned IP addresses for each network component. A DNS (domain name service) is used to translate between the domain names and the IP addresses of network components and services. DNS servers are well known in the art and are used to resolve the domain names to IP addresses on the Internet.
Similarly, Network Time Protocol (NTP) is used to synchronize time references within the network components for security and audit activities. It is important to have a consistent and synchronized clock so that the order and the timing of transactions within the gaming network can be known with reliability and certainty. Network information can be gathered centrally at a single workstation by using the Remote Monitoring (RMON) protocol. SNMP (simple network management protocol) allows network management components to remotely manage hosts on the network, thus providing scalability. In one embodiment of the gaming network, SNMPv3 is used to take advantage of embedded security mechanisms to mitigate malicious attacks made against the configuration management function. Still further, TFTP (trivial file transfer protocol) is used by servers to boot or download code to network components.
In one embodiment, the network may be implemented using the IPv6 protocol designed by the IETF (Internet Engineering Task Force). When using IPv6, the network may take advantage of the Quality of Service (QoS) features available with IPv6. QoS refers to the ability of a network to provide a guaranteed level of service (i.e. transmission rate, loss rate, minimum bandwidth, packet delay, etc). QoS may be used as an additional security feature in that certain transactions may request a certain QoS as a rule or pursuant to some schedule. Any fraudulent traffic of that nature that does not request the appropriate QoS is considered an attack and appropriate quarantine and counter measures are taken.
Similarly, the Type of Service (ToS) capabilities of IPv4 may also be used in a similar manner to provide additional security cues for validation of transactions. Again, certain types of transactions may be associated with a particular specific ToS or a rotating schedule of ToS that is known by network monitors.
Traffic Content
In an embodiment of the gaming network, the traffic content varies in size and sensitivity. Messages may comprise transactional messages related to game play, such as coin-in. Other messages may be related to management, administration, or sensitive information, such as administrator passwords, new game code, pay tables, win rates, patron personal data, or the like.
Security
The gaming network includes network security features, host security features, audit protocols, and design architecture approaches to reduce the likelihood of success of network attacks. Where attacks cannot be prevented, the gaming network attempts to make such attacks expensive in terms of the computational power required, the time, risk, effect, and duration of the attack. Identification of attacks and the rapid recovery from such attacks should be emphasized, as should the limiting of the effect of any attacks.
Accordingly, the gaming network provides for traffic confidentiality. All nodes within the network exchange information that is confidentially protected. One method for providing confidentially protected data is by using encryption. A number of encryption schemes may be used, such as an FIPS approved encryption algorithm and an NIST specified encryption mode, such as the Advanced Encryption Standard (AES).
In addition, all nodes within the gaming network apply source authentication and integrity of all traffic. A suitable message authentication mechanism may be, for example, an FIPS approved algorithm such as the Keyed-Hash Message Authentication Code (HMAC) and SHA-1. All nodes automatically drop messages that have been replayed. As noted above, replayed messages are a means of attack on network security.
Key management mechanisms should be sufficient to resist attack. In one embodiment, a 1024 bit Diffie-Hellman key exchange with a 1024 bit DSA/RSA digital signature is used to render key attacks computationally infeasible. It should be noted that the key sizes are given as examples only. Smaller or greater key size can be used in the gaming network as security recommends. The gaming network should be robust, maintaining the availability of critical services. The network should include protection against misrouting and also discard any traffic that has a source or destination outside of the network. The gaming network should also require a minimum level of authentication and assurance before permitting an additional device on the network and prevent such connection when the assurance is not provided.
Host protection and security includes secure host initialization where the host performs a self-integrity check upon power-up initialization. All operating system components that are not needed are disabled. When software patches are downloaded to the gaming network, the host verifies them. The host checks for unused IP ports and disables them prior to connecting to the gaming establishment network. When processing network traffic, any traffic not addressed to the host is dropped from the processing stack as soon as possible. In the gaming network, all service, guest, and default administrator accounts that may be part of the operating system are disabled. In one embodiment, one-time passwords and/or multi-part passwords are used for remote login, if remote login is enabled. The one-time password may itself be a multi-part password. When using a multi-part password, different trusted individuals each hold a part of the multi-part password. The entire password is required for enablement of the system. This prevents any single individual from compromising security. Moreover, all host software components are operated with the lowest privilege necessary for sufficient operation. For example, software that can operate with “user” privilege will do so, to limit its usefulness to an attacker.
Audit requirements include integrity protection of audit logs from date of creation and throughout their use. Events that are audited in an embodiment of the gaming network include account logon events (both success and failure), account management (both success and failure), directory service events (failure), logon events (success and failure), object access (failure), policy changes (success and failure), privilege use (failure), system events (success and failure), access to a host or networking device logged by user name and the time of access, and all other internal user actions. Anomalous behavior is audited and logged for purposes of evidence for law enforcement and/or attack recognition. Audit information is collected and stored in a secure manner to preserve the chain of evidence. If there is a failure of the audit system, automatic shutdown is initiated.
The gaming network is designed so that there is no single point of failure that would prevent remaining security features from operating when one is compromised. The gaming network also will continue to operate in the event of bridging to another network, such as the Internet.
Secure Initialization of Network Devices
The gaming network provides confidence that a network device is contacting a legitimate DHCP server rather than a spoofed server. The gaming network uses Internet Key Exchange (IKE) in one embodiment. There are a number of modes and phases of IKE. Phase I of IKE includes two modes, referred to as “main mode” and an “aggressive mode”. Phase II has a single mode referred to as “quick mode”. Main mode takes six packets to complete while aggressive mode takes 3 packets. Quick mode takes 3 packets to complete. In some embodiments, Phase I is used for initialization and Phase II is used to create security for subsequent traffic and messages. FIG. 3 is a flow diagram illustrating the initialization of a network device using main mode of Phase I.
Phase I is used to authenticate devices to each other and to protect subsequent Phase II negotiations. In the following description, the network device is referred to as the initiator and the server is referred to as the responder. Referring to FIG. 3 , at step 301 , the initiator sends a first IKE packet to the responder. The packet may or may not include vendor ID's (VID) that can inform the responder of the extensions the initiator supports. Each IKE message includes a mandatory Security Association (SA) that defines how to handle the traffic between the two devices. The SA of the initial packet lists the security properties that the initiator supports, including ciphers, hash algorithms, key lengths, life times and other information. At step 302 , the responder replies with an IKE packet that may or may not include a VID, but does include a mandatory SA payload. At this stage, the packets are not encrypted because there is still no key for encryption.
The third packet, at step 303 , is from the initiator to the responder and uses the Diffie-Hellman key exchange protocol. The packet contains a key exchange (KE) payload, a NONCE payload, and a certificate request (CR) payload. The public keys are created whenever the phase I negotiation is performed and are destroyed when the phase I SA is destroyed. The NONCE payload is a large random number that has not been used before on the network (“never-used-before”) and is useful in defeating replays. The CR payload includes the name of the Certification Authority for which it would like to receive the responder's certificate. (Note that the CR can be sent in the third and fourth packets or in first and second packets, as desired).
At step 304 , the responder returns its own KE, NONCE, and CR in the fourth packet. The third and fourth packets are used by each device to generate a shared secret using public key algorithms. Because only public keys are sent in this exchange, and no encryption key is yet available, the messages are still not encrypted.
At step 305 , the initiator uses the KE to generate a shared secret and uses it to encrypt the fifth message. The fifth message includes an Identification (ID) payload, zero or more certificate (CERT) payloads (or CRL) and a Signature payload (SIG) that is the digital signature that the responder must verify. The ID payload is used to tell the other party who the sender is and may include an IP address, FQDN (fully qualified domain name), email address, or the like. In an embodiment of the gaming network, it is an IP address. The CERT payload is optional if the initiator or responder cache the public key locally. In an embodiment of the gaming network, the public key is not cached locally and failure to receive a CERT payload is a failure of the negotiation. The SIG payload includes the digital signature computed with the private key of the corresponding public key (sent inside the CERT payload) and provides authentication to the other party.
At step 306 , the responder sends a message with its ID, CERT, and SIG payloads. When both the initiator and responder have successfully verified the other party's SIG payload, they are mutually authenticated. The result of the successful negotiation is the Phase I SA.
After the phase I negotiation is successfully completed, the phase II negotiation can proceed to create SA's to protect the actual IP traffic with an IPsec protocol. Each of the phase II packets are protected with the phase I SA by encrypting each phase II packet with the key material derived from phase I. Phase II in the gaming network is illustrated in FIG. 4 . At step 401 , the initiator sends a message with a number of payloads. The message includes SA and NONCE payloads that are the keying material used to create the new key pair. As noted above, the NONCE payload includes random never-used-before data. The SA payload is the phase II proposal list that includes the ciphers, HMACs, hash algorithms, life times, key lengths, IPsec encapsulation mode, and other security properties. Optionally, the message may include IDi (initiators ID) and IDr (responders ID), which can be used to make local policy decisions.
At step 402 , the responder replies with a message with the same payload structure as the first message. The initiator replies with a HASH value at step 403 . After phase II is completed, the result is two SA's. One is used for inbound traffic and the other for outbound traffic.
Rekeying is done when the lifetime of the SA used for protecting network traffic expires. In one embodiment, PFS (perfect forward secrecy) protocol is used for rekeying. The network ensures the set of secret keys generated by one protocol message exchange is independent of the key sets generated by the other protocol message exchanges. This means compromise of one key set does not lead to compromise of the other sets
Additional protection for network traffic is provided by use of a “virtual private network” (VPN). As a result, all network traffic is protected, and not just TCP/IP traffic.
In an alternate embodiment, the network may be constrained to a particular regulatory jurisdiction. In this embodiment, a regulatory jurisdiction has its own private key and a multi-tiered approach is used to validate devices. During initialization, a combination key at an administrative location is used to sign messages and data. If there are attempts to communicate outside the jurisdiction, the lack of the regulatory jurisdiction key prevents communication. This is another security feature that is used to limit inside and outside attacks on the gaming network.
In one embodiment, the system uses a secure key server to store private keys and certificates. The secure key server requires multi-part passwords as described above for access and enablement. The secure key server is resistant to network or Internet attacks, denial of service attacks, and other software or protocol attacks. The secure key server is also resistant to physical attacks such as forced break-in attempts, changes in temperature, changes in pressure, vibration, attempts to disassemble the secure key server. In one embodiment, any attack attempt results in the destruction of stored keys, certificates, etc, to prevent compromise of the system.
In another embodiment, a physical transfer of certificates may be implemented as an additional security protection. No game machine or other device may be added to the system without a physical visit and installation of a certificate. In other words, a mere handshaking protocol is not sufficient to add a device onto the system. Rather, a potential new device will require a trusted person or persons to activate the device, install an appropriate certificate, and add it to the network.
Blocking Illegitimate Traffic
As described above, the gaming network uses IKE, IPsec, and VPN to protect legitimate traffic from mischief. The gaming network also provides systems to block illegitimate traffic. Firewalls are installed at choke points within the access and distribution layers to isolate network segments from one another. Firewalls can limit the spread of damage from propagating beyond the compromised network segment. The use of NONCE never-used-before random numbers also prevents illegitimate traffic by blocking replay of legitimate messages. IKE and protection of all post initialization traffic makes it more difficult for illicit messages to achieve successful delivery.
In addition to detecting false messages using the techniques above, the gaming network reduces the possibility of access to the network by blocking all unused IP ports. Only IP ports required for gaming operation are enabled. To further limit the ability of outside access to the gaming network, private IP addresses are used. Typically IP addresses provide global uniqueness with the intention of participating in the global Internet. However, certain blocks of addresses have been set aside for use in private networks. These blocks of IP addresses are available to anyone without coordination with IANA or an Internet registry. Since multiple private networks may be using the same block of IP addresses, they lack global uniqueness and are thus not suitable for connection on the global Internet. Private network hosts can communicate with all other hosts inside the private network, both public and private. However, they cannot have IP connectivity to any host outside of the enterprise. Allocation of private network IP addresses may be accomplished pursuant to RFC 1918 protocol.
In another embodiment, the volume of network traffic is monitored at each link and compared to expected flow rates and/or historical flow rates. Histograms may be generated so that analysis and comparison of flow rates may be accomplished. Heuristic algorithms may be implemented to determine if the flow rate is within an acceptable range. If not, a data leak or attack is assumed and appropriate alarms are triggered. Heavy flow areas can be disabled so that appropriate investigation can be made.
Detecting and Reacting to Attacks
Intrusion detection system (IDS) sensors and/or intrusion prevention systems are installed between the core, distribution, and access layers. IDS and intrusion prevention sensors may also be installed at choke points within the access and distribution layers to detect malicious traffic within these layers. One suitable IDS is “arpwatch” (www.securityfocus.com/tools/142) that monitors IP address changes, MAC addresses, flow rate changes, and other network activity and can be configured to notify an administrator when IP/MAC/DID address bindings change for a device on a gaming network. When a change is detected, automatic isolation procedures may be implemented to isolate the possible intrusion. Subsequent analysis and review by network administrators can determine appropriate responses.
The system may keep a physical map of the location of the IDS sensors so that when an intrusion is detected, the physical location of the attack can be immediately identified. Security can be dispatched to the location to apprehend the attackers, appropriate systems may be shut down or disabled, and perimeter measures can be taken to increase the chances of securing the attacker.
FIG. 5 is a flow diagram of one embodiment of the operation of the intrusion detection system of the gaming network. At step 501 , the gaming network is initialized and IP addresses are assigned to network devices. This may be accomplished using the technique described in FIGS. 3 and 4 or by any other suitable technique. At step 502 , a mapping of the IP addresses of the network devices, their respective MAC addresses, and the DID is performed. This binding should remain stable through a session unless the core layer specifically initiates a change or if a regularly scheduled or anticipated change occurs.
At step 503 , the system monitors the network. Such monitoring may be accomplished by any suitable means for tracking IP/MAC/DID mapping. As noted above, one such method includes Arpwatch. At decision block 504 , it is determined if there has been any change to the IP/MAC/DID mapping. If the answer is no, the system continues monitoring the network at step 503 . If the answer is yes, meaning that there has been some change in IP/MAC/DID mapping, the system disables the IP address and the network device associated with the MAC address and DID in question at step 505 . This step of disabling may also include shutting down ports or sections of the network to contain or limit any presumed attack on the network. The system notifies the administrator at step 506 so that analysis and correction may begin.
In an alternate embodiment of the system, the mapping may be between any two of the parameters IP address, MAC, and DID. In addition, there may be multiple devices inside of the gaming machine. In some instances, the DID of the gaming machine may be used exclusively. In other instances, the DID of an associated device such as a reel controller, LED controller, CPU, safeRAM, hard drive, physical cabinet, printer, or other associated devices may be used singly or in combination with the gaming machine DID. Each associated device may have a unique ID (such as a 32 bit hex value) so that the combination of game machine DID and/or one or more associated device DID's results in a unique ID that is difficult to duplicate, we call this a “binding”. Fraudulent communications that lack the requisite binding will be detected easily. Further, malicious hardware that attempts to join the network will lack not only the correct device ID's but also the combination bindings described above.
In yet another embodiment, the DHCP server is pre-loaded with a list of valid IP addresses, MAC addresses, machine and associated device DIDs, and IP/MAC/DID bindings. If the game machine requesting initialization or permission to join the network is not on the pre-determined list, the machine is not permitted on the network and an attack is logged. An alarm can be triggered so that the attacker can be identified and captured when possible.
In some instances, it may be useful to use dynamically assigned IP addresses in a gaming network. In such a situation, it is still important to be able to identify with certainty that only valid devices are on the network. In one embodiment, globally unique identifiers (GUIDs) are used to identify managed switches at one or more levels of hierarchy. For example, the switch could be at the game cabinet level, a bank of machine level, and/or a casino level. The GUID is used to positively identify a valid managed switch.
Associated with each managed switch is what is referred to herein as a “collection” of devices associated with that switch. The DIDs and MAC addresses can be used to identify the devices as being valid members of the collection. The dynamically assigned IP address can then be mapped to the collection so that the members of the network are known, and communication with the collection and its constituent devices can occur. The IP addresses can be subnet IP addresses for members of the collection if desired.
GUIDs are registered at network creation and when valid devices are added to the system. Once registered, dynamically assigned IP addresses can be properly mapped for communication using the IP address if desired.
In another embodiment, each network device has its own GUID that is registered and may be mapped to a dynamically assigned IP address. If desired, the bindings described above may be implemented even with dynamically assigned IP addresses, once the proper mapping has been made using GUIDs.
Another embodiment takes advantage of GUIDs to create logical collections instead of physical collections. A logical collection may be disparate physically but may be useful for certain management, reporting, or game play operations.
By being able to uniquely identify devices and collections, it is possible to create filters that allow communication with subsets of network devices at levels from single devices to collections to all devices and anywhere in between.
An additional security feature of the gaming network requires a secure boot sequence within each gaming machine and server such that an initial boot is accomplished using code residing in unalterable media. The initial boot code verifies the operating system and all network services it includes. Consequently, network services will not be enabled until the full operating system has been verified as legitimate.
FIG. 6 is a flow diagram illustrating the boot initialization of a network device, such as a gaming machine in one embodiment of the gaming network. At step 601 , the device boots from a locally stored unalterable media. At step 602 , the network device establishes security for communication with a network host. This may be accomplished by the IKE phase I method described in FIG. 3 . Once secure host communication is established, traffic security is established at step 603 . This may be accomplished by IKE phase II, as described in FIG. 4 .
If any of the steps fail in this sequence, communication is terminated and a network administrator is notified. At step 604 , the network device submits its operating system for verification. Such verification may be by any desirable method and may be in addition to other network security features. At step 605 , the host receives the verification request and checks the operating system of the network device.
At decision block 606 , it is determined if the network device contains a legitimate operating system. If not, the device is disabled at step 607 . This process may initiate notice to a network administrator, as well as, disabling of some portion of the network associated with the device in an attempt to mitigate damage from an attack. If the operating system of the network device is legitimate at step 606 , the host enables the appropriate network services for the network device at step 608 and operation begins. As noted above, all traffic is protected in the gaming network to some degree. In addition, some traffic includes additional security checks.
In one embodiment, the game machine provides a secure boot and initial O/S verification as follows. EPROM verification software resides within an input/output processor (IOP). The verification software verifies all EPROMs on the IOP board (i.e., mains and personalities) upon application of power to the game machine. Next, after the application of power to the machine, the BIOS+ performs a self-verification on all of its code. Once satisfactorily completed, the board (e.g. a Pentium class board) begins executing code from the BIOS+contained in the conventional ROM device. This process verifies the conventional ROM device and detects any substitution of the BIOS+.
Upon boot-up of the processor, the BIOS+ executes a SHA-1 verification of the entire O/S that is presented. The digital signature is calculated and compared with an encrypted signature stored in a secure location on the game machine using, for example, the RSA private/public key methodology. If the signatures compare, the BIOS+ allows the operating system to boot, followed by the game presentation software. Next, display programs and content are verified, before being loaded into the IOP RAM to be executed for normal game operation.
During communication, each message is protected using the security of the gaming network. However, certain messages incorporate additional security checks even if the package is considered trustworthy. For example, code downloads may require that they be cryptographically signed and verified before executing. For messages such as these, the digital signature for the code is independent of and in addition to the authentication provided by VPN and the other network security features. In addition to the digital signature check and verification, the gaming network implements increasing number versioning of network downloaded updates so that rollback attempts may be mitigated or eliminated.
It may be desired to have some network communication links be wireless instead of hard wired. In such an environment, the gaming network includes wireless intrusion detection mechanisms detecting, for example, 802.1.1a/b/g devices. Such detection has scope beyond network attacks and may detect wireless attacks on the gaming establishment, even if not specifically targeting the gaming network.
It will be apparent from the foregoing that, while particular forms of the claimed invention have been illustrated and described, various modifications can be made without departing from the spirit and scope of the claimed invention. Accordingly, it is not intended that the claimed invention be limited, except as by the appended claims. | The gaming network described herein includes network security features, host security features, audit protocols, and design architecture approaches to reduce the possibility of network attacks. The gaming network provides for traffic confidentiality, encryption, message authentication, secure authentication mechanisms, anti-replay protection of traffic, key management mechanisms, robust network availability, misrouting and redirection protection and prevention, rejection of external traffic, and a high entry-barrier to device addition to the network. The host protection and security includes secure host initialization, disabling unneeded components, download verification, disabling of unused IP ports, discarding traffic, strong passwords, dynamic one-time passwords for remote login, disabling default accounts, and appropriate “least-level” device privileges. Audit requirements include integrity protection of audit logs, appropriate definition of auditable events, auditing of anomalous behavior, chain of evidence preservation, shutdown if audit disabled, full log entry audit, personal ID and time access audit trail, and auditing of internal user actions. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to padding for protective helmets, and more particularly a removable supplementary padding allowing an adaptation of the helmet volume to the form and dimensions of the user's head. The invention also relates to helmets equipped with the padding.
One already knows protective helmets used in various fields and which are worn by a variety of diverse users such as cyclists, motorcyclists, firemen, skiers, and others, such as airplane or helicopter pilots.
All the current helmets, whatever their use, include an external rigid shell having a generally spherical shape, and whose cavity is thus formed and includes elements of protective padding and comfort intended to encase and protect the head of the user, while rendering the wearing of the helmet comfortable.
The protective helmet must have appropriate interior dimensions and be in conformity with the dimensions, form, and volume of the head of the user. Helmets being industrially-made products, it is thus not possible, taking into account the diversity of the wearers' heads, to industrially manufacture specific helmets adapted to each user.
Thus, the helmets are marketed according to various sizes, but others include systems of adjustment in order to adjust to and be regulated by the desired dimensions and volume to adapt to the user.
U.S. Pat. No. 5,765,234 shows a helmet whose adjustment includes several adjustable knobs which cover the interior of the helmet, which are to be in contact with the head of the user. It was understood that this device is not at all satisfactory, because the contacts with the interior of the helmet are specific and render the wearing of the helmet particularly uncomfortable, and that, of course, affects its safety.
One knows also the device shown in the American patent U.S. Pat. No. 3,082,427 includes a deformable internal cap made of an adjustable mesh. This device forms part of an obsolete technology, and the helmet is meant, to some extent, to be floating, and is thus uncomfortable and a little unsafe.
U.S. Pat. No. 5,003,636 discloses an adjustment including a plurality of inflatable compartments. This concept, even if it appears, at first sight, alluring, is a difficult technology to implement and is not very reliable because the inflatable cells are constantly damaged.
All of the former systems thus present a certain number of disadvantages and those being, in particular, expense, a lack of reliability, discomfort, and a lack of practicality.
SUMMARY OF THE INVENTION
The present invention thus wants to solve these disadvantages by proposing a modular and modifiable supplementary padding, constituted by a removable envelope into which can be introduced one or more supplementary elements of padding, the aforementioned envelope being advantageously affixed in a removable way to the interior of the helmet. The padding is between the helmet itself, with its resident padding and lining, and the cranium of the user.
Thus, according to the invention, padding for a protective helmet is a supplementary padding, including an envelope intended to be attached inside the helmet; the aforementioned envelope being made out of flexible material and including at least a supplementary element of padding made out of synthetic foam, while the envelope includes at least one opening allowing the introduction of the supplementary element into the aforementioned envelope. As well as including the means of attaching the padding inside the helmet.
According to a supplementary characteristic, the supplementary padding is intended to be attached inside the helmet in a removable way by means of removable attachments, for example, using one or more bands of auto-gripping textile, such as the type with hooks.
According to a preferred embodiment, the supplementary padding is an envelope having the general shape of a ‘T’, which includes a longitudinal central branch, whose front end is elongated laterally towards the left by a left side branch and towards the right-hand side by a right side branch.
According to supplementary characteristics of the preferred embodiment, the supplementary padding is made of a lower wall, connected by its edge to an upper wall, the aforementioned walls being made of a soft material such as, for example, fabric, which is able to be deformed, while the longitudinal central branch includes, on its upper wall in contact with the lining fabric, an opening to constitute a longitudinal central pocket into which can be introduced a supplementary element of central padding, while the left side branch includes, on its upper wall in contact with the lining fabric, an opening to constitute a longitudinal central pocket, into which can be introduced a supplementary element of central padding, the longitudinal right side branch including, on its upper wall, an opening to constitute a longitudinal central pocket, into which can be introduced a supplementary element of central padding.
According to another characteristic, the central junction of the three branches of the envelope includes, on its upper wall, an opening to constitute a longitudinal central pocket, into which can be introduced a supplementary element of central padding.
According to another characteristic, it is the higher wall of the envelope which includes at least one band of self-gripping textile of the type with hooks.
The invention also relates to the protective helmet equipped with supplementary padding, the aforementioned helmet being, for example, a rigid primary shell, including an internal padding commonly called “calotin”, made out of rigid synthetic foam such as expanded polystyrene or of polyurethane foam, and includes, in addition, an interior trim including a layer of foam ensuring the comfort of the helmet and a comfortable lining fabric intended, in particular, its interior decoration, while the removable supplementary padding is attached to the comfortable lining fabric.
Let us add that, according to the preferred embodiment, the central junction of removable padding is affixed on the frontal zone of the interior of the helmet, while the two side branches are affixed laterally in the area of the temples, and that the longitudinal central branch is affixed in the plane of symmetry which extends from the frontal zone backwards, for example, to the nape of the neck.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics and advantages of the invention will emerge from the description which follows, referring to the annexed drawings which are given only by way of nonrestrictive examples.
FIG. 1 is a prospective view of a helmet without supplementary padding, while FIG. 1 a shows the padding right before its installation in the helmet.
FIG. 2 is a prospective view of a helmet, equipped with supplementary padding, with a part of the aforementioned padding shown in phantom.
FIG. 3 is a front view of the helmet equipped with its supplementary padding.
FIG. 4 is a side view of the helmet equipped with its removable padding, while the FIG. 4 a is a sectional view, in enlarged scale, revealing the succession of layers laid out inside the shell of the helmet, including the layers of supplementary padding.
FIG. 5 is a schematic view, in perspective, of the supplementary padding before its installation.
FIG. 6 is a top view of the supplementary padding laid flat, equipped with its supplementary elements of padding.
FIG. 6 a is a cross-section of A-A of the FIG. 6 , while FIG. 6 b is a cross-section of B-B of FIG. 6 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The protective helmet ( 1 ), intended to be equipped with the padding of the invention, represented by way of examples in FIGS. 1 to 4 , is, for example, a helmet for airplane pilots. It presents a longitudinal plane of general symmetry (P) which includes in a known way a principal external shell ( 2 ) including a resident internal padding, commonly called “calotin” ( 3 ), and an internal lining ( 5 ).
The principal external shell ( 2 ) is made up of an appreciably spherical wall ( 4 ) along a general vertical plane of symmetry (P) which is advantageously made of composite material including a stack of layers made of reinforcing fibers, impregnated and bound by a resin matrix. The fibers can be made of carbon or polyethylene, nylon, aramide, glass fibers, while the matrix can be a resin of the thermal hardening or thermoplastic type. Of course, the shell could be in any other material such as, for example, steel.
The resident internal padding ( 3 ) includes a layer of rigid synthetic foam such as foam of expanded polystyrene or polyurethane or other types of polymer. The resident internal padding ( 3 ) ensures the protection of the user's cranium by impact damping and thus includes an enveloping wall, for the cranium on the upper surface ( 30 ) conforms in large part to the interior shape of the interior surface of the shell, while its lower surface ( 31 ) conforms to the shape of cranium.
The resident padding ( 3 ) thus ensures the protection of the cranium, while it is over laid with an interior trim ( 5 ), including a layer of foam ( 6 ) ensuring the comfort of the helmet, and a comfortable lining fabric ( 7 ), in particular intended, for interior decoration, and attachment of the padding.
The supplementary padding, which is advantageously removable ( 8 ), is formed of an envelope ( 9 ) made of deformable material, such as fabric or the like, inside of which is at least one supplementary element of padding ( 10 ) made of a similar material or foam element. In addition, the envelope ( 9 ) includes at least one opening allowing the introduction and/or withdrawal and/or replacement of the supplementary element. Moreover, the means of attachment are designed to affix the supplementary padding ( 8 ) inside the shell ( 2 ), and more precisely to affix the removable padding onto the comfortable lining fabric ( 7 ).
In the preferred embodiment, the removable supplementary padding ( 8 ) is an envelope ( 9 ) having the general form of a ‘T’, which includes a longitudinal central branch ( 11 ), whose frontal end (AV) is prolonged laterally towards the left (GA) by a left side branch ( 12 ), and towards the right (DR) by a right side branch ( 13 ).
The removable supplementary padding ( 8 ), made up of its various branches ( 11 , 12 , 13 ), is an envelope ( 9 ) formed of a lower wall ( 14 ), connected by its edge to an upper wall ( 15 ), the aforementioned walls being made of a soft material such as, for example, fabric, able to be deformed and installed inside the helmet. Let us specify that the upper wall ( 15 ) of the envelope ( 9 ) is in contact with the interior of the helmet and more exactly with the comfortable lining fabric ( 7 ), while the lower wall ( 14 ) is in contact with the head of the user.
One will note that the upper wall ( 15 ) includes at least one opening ( 16 a , 16 b , 16 c , 16 d ) allowing the introduction into the envelope ( 9 ) of at least one supplementary element of padding ( 10 a , 10 b , 10 th, 10 d ), advantageously made out of synthetic foam.
According to the preferred embodiment, the envelope includes four openings ( 16 a , 16 b , 16 c , 16 d ) allowing the introduction of four supplementary elements of padding ( 10 a , 10 b , 10 c , 10 d ).
Thus, the longitudinal central branch ( 11 ) includes, on its upper wall ( 15 ) in contact with the lining fabric ( 7 ), an opening ( 16 a ) to access a longitudinal central pocket ( 160 a ) into which can be introduced a supplementary element of central padding ( 10 a ).
In addition, the left side branch ( 12 ) includes, on its upper wall ( 15 ) in contact with the lining fabric ( 7 ), an opening ( 16 b ) to constitute a central longitudinal pocket ( 160 b ), into which can be introduced a supplementary element of left side padding ( 10 b ).
As well, the longitudinal right side branch ( 13 ) includes, on its upper wall, an opening ( 16 c ) to access a longitudinal central pocket ( 160 c ), into which can be introduced a supplementary element of right side padding ( 10 c ).
In addition, the central junction ( 17 ) of the three branches ( 11 , 12 , 13 ) includes, advantageously, on its upper wall, an opening ( 16 d ) to access a longitudinal central pocket ( 160 d ), into which can be introduced a supplementary element of forward padding ( 10 d ).
Let us add that the supplementary element of central padding ( 10 a ) advantageously has the shape of a trapezoid whose small base ( 22 ) is in front and the large base ( 23 ) in the back, in order to be broader across the back of the user's cranium.
The various openings ( 16 a , 16 b , 16 c , 16 d ) are, for example, simple slits made in the upper wall ( 15 ) of the envelope ( 9 ).
The envelope ( 9 ) includes removable padding ( 8 ) with its supplementary elements of padding ( 10 a , 10 b , 10 th, 10 d ) which is intended to affix itself inside the helmet onto the decorative fabric ( 7 ) of the internal lining ( 5 ). Thus, the central junction ( 17 ) is affixed on the frontal zone ( 18 ) of the interior of the helmet, the two side branches ( 12 , 13 ) are affixed laterally in the zone of the temples, respectively ( 19 a , 19 b ), while the longitudinal central branch ( 11 ) is affixed in the symmetry plane which extends from the frontal zone ( 18 ) backwards, for example, to the nape of the neck ( 20 ).
To retain the removable padding ( 8 ) inside the helmet, a means of attachment is envisioned, the latter allowing, for example, to affix to the upper wall ( 15 ) of the envelope ( 9 ) the on decorative fabric ( 7 ). These means are, for example, self-gripping. Thus, it is envisaged between the interior wall of the helmet and, more precisely, between the lining fabric ( 7 ) and the upper wall ( 15 ), an attachment out of a gripping textile of the type marketed under the “Velcro” trademark, formed by a band of textile ( 21 ) of the type with hooks, intended to cooperate with the velvet of the lining fabric ( 7 ). Thus, the upper wall ( 15 ) of the envelope for the removable padding ( 8 ) includes, for example, five bands of gripping textile of the type with hooks ( 21 a , 21 ′ a , 21 b , 21 c , 21 d ), respectively attached on the longitudinal central branch ( 11 ), the left side branch ( 12 ), the right side branch ( 13 ) and the junction ( 17 ).
It was understood that, thanks to the openings ( 16 a , 16 b , 16 c , 16 d ), the user can remove the supplementary padding elements ( 10 a , 10 b , 10 c , 10 d ) which are removable to, if required, replace them with other removable supplementary elements of padding, which could be different, such as, for example, a different thickness, or a different matter, namely, harder or more flexible, to even a different form.
Thus, a given envelope can correspond to several different types of supplementary padding elements, so that the user can choose the supplementary padding elements allowing him to obtain an optimal adaptation of the interior volume of the helmet, and thus personalize his helmet.
It goes without saying that the supplementary padding which with the form of a perfect ‘T’ in the preferred embodiment proposed by way of example, could have all other forms to adapt to the configuration of the interior of the helmet in which it is intended to be mounted. Thus, and for example, two side branches of the T ( 12 , 13 ) which are in line with each other in the illustrations could, for example, be convergent or divergent. Also let us add that, in the shown illustrations, the two side branches ( 12 , 13 ) are perpendicular but it could, of course, be arranged differently, and have all other forms adapted to the helmet into which supplementary padding is destined.
Of course, the invention is not limited to the preferred embodiment described and represented by way of examples, but it includes also all the technical equivalents as well as their combinations. | Supplementary padding ( 8 ), for a protective helmet ( 1 ) includes a T-shaped envelope ( 9 ) designed to be removably affixed inside the helmet. The envelope is made of a flexible material and defines pockets for receiving supplemental padding elements ( 10 a, 10 b, 10 c, 10 d ), optionally made of synthetic foam. The envelope includes at least one opening for inserting the supplemental padding elements into said envelope and a self-gripping textile ( 21 a, 21 b, 21 c, 21 d ) for releasably adhering the envelope to lining ( 7 ) of the helmet. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a system whereby an unattended vehicle passenger, such as an infant or a toddler or even a pet, is detected prior to harm befalling the passenger from temperature extremes.
2. Background of the Prior Art
As hard as it is for many to fathom, the number of small children left unattended in vehicles is quite alarming. While most such incidents of leaving a small child or even a pet unattended, terminate without any undue harm, on some occasions, the passenger can suffer serious injury or death, typically from hyperthermia, but also from hypothermia for wintertime unattandance.
When a body's core temperature reaches about 104 degrees Fahrenheit, heat stroke sets in as the body's thermoregulatory system starts to become overwhelmed. Once the body's core temperature reaches about 107 degrees Fahrenheit, death occurs as cells are severely damaged and organs fail. On a sunny day, the interior temperature of a vehicle can rise 30 degrees or more above the ambient temperature in about 20 minutes, with cracking of the window having almost no effect on the temperature rate of increase. A body, especially a young body of an infant or toddler, can quickly succumb to the heat effects within the interior of an unattended car.
Leaving a passenger unattended typically happens in one of three ways. Sometimes, a parent or guardian intends to make a quick stop, such as the grocery store, and wants to run in, get a few items and return to the vehicle. The parent or guardian may not want to go through the trouble of unbuckling the child from his or her car seat and thereafter buckle the child back up; or the parent or guardian may not want to disturb a sleeping child. In either case, the adult either gets distracted from the original task and spends more time away from the vehicle, or simply does not appreciate how quickly the temperature can rise (or fall) in the unattended vehicle.
The second type of situation involves the parent or guardian who simply forgets that they are transporting a child in the vehicle and leaves the child in the vehicle unattended, often for hours. This latter situation is responsible for the majority of child deaths from being left unattended.
A third type of situation involving children who have died from heat stroke in a vehicle is when a child gains access to an unattended vehicle and is thereafter unable to extricate himself or herself from the vehicle.
While leaving a child unattended in a vehicle for any amount of time is unthinkable to most rational people, such neglect does happen, resulting in dozens of child deaths each year, and countless pet deaths as well. In all cases, the death of the child is both tragic and avoidable.
In order to address this problem, systems have been developed that deal with an unattended passenger within a vehicle. Such systems, which range from the very simple to the very complex, come in a multitude of architectures relying on various methods for passenger detection and work with varying degrees of success. However, prior art systems suffer from certain drawbacks.
Some systems are exceedingly complex in design and/or installation, often requiring a factory trained professional to install the device and integrate the device into the vehicle's computer system. Not only are such systems cost-prohibitive, many automotive manufacturers are reluctant to assist in such device installations. Other devices simply have too many false detections. While rescuing a child from a hot unattended vehicle is desirable, improperly rolling down the windows and possibly even starting the vehicle due to a false detection may not prove acceptable to a vehicle owner, especially if an opportunistic thief happens upon the vehicle prior to the owner or law enforcement arriving on scene.
What is needed is a system that is able to detect the presence of an unattended passenger within a vehicle while addressing the above mentioned shortcomings found in the art. Such a system must be able to detect the presence of an unattended passenger within a vehicle, wherein the temperature of the interior of the vehicle is approaching or has exceeded a threshold temperature (either too hot or too cold) and issues an appropriate alarm, while substantially decreasing the possibility of false detections which lead to inappropriate alarms. The system must be operable as a standalone system, yet should be able to integrate with certain subsystems of the vehicle without the need to hardwire the system to the vehicle's computer.
SUMMARY OF THE INVENTION
The unattended vehicle passenger detection system of the present invention senses for the presence of an unattended passenger, including a child or a pet, and sounds an appropriate alarm if the interior temperature of the vehicle has crossed a predetermined threshold level (either too hot or too cold), so that corrective action can be taken to prevent harm to the unattended passenger. The unattended vehicle passenger detection system uses multiple passenger sensing subsystems that can be used independently, or in combination, so that if the interior temperature has exceeded the threshold, and one of the subsystems senses a passenger within the vehicle, then the unattended vehicle passenger detection system can use another of the subsystems to verify passenger presence prior to initiating an appropriate alarm thereby reducing false alarms. However, since child (or pet) safety and rescue are paramount, the system will activate if only one of the sensors detects the presence of the child (or pet) and the temperature has exceeded the predetermined thresholds. While the unattended vehicle passenger detection system can also be wired into a vehicle's computer, it can be used as a standalone unit, mimicking the FOB signals emitted by the vehicle's FOB. Such FOB's are common on many vehicles, including entry level vehicles.
The unattended vehicle passenger detection system of the present invention is comprised a control unit that is mounted within a vehicle. A temperature sensor that senses temperatures is mounted within an interior passenger compartment of the vehicle, the temperature sensor communicatively coupled (either wired or wirelessly) to the control unit. A carbon dioxide sensor that senses carbon dioxide levels is mounted within the interior compartment of the vehicle, the carbon dioxide sensor communicatively coupled (either wired or wirelessly) to the control unit. An alarm system is communicatively coupled (either wired or wirelessly) to the control unit such that the alarm system is capable of issuing a first alarm command in order to activate a first alarm event. The temperature sensor senses the temperature within interior compartment and if the temperature crosses a first predetermined threshold temperature which is outside a safe temperature range, then the carbon dioxide senses the carbon dioxide level within the interior compartment of the vehicle and this carbon dioxide level is stored by the control unit as a baseline carbon dioxide level, and thereafter the carbon dioxide sensor senses at least one subsequent carbon dioxide level within the interior compartment of the vehicle and the control unit compares each of the at least one subsequent carbon dioxide levels against the baseline carbon dioxide levels in order to obtain a differential, and if the differential is positive and exceeds a predetermined amount, the control unit commands the alarm system to issue the first alarm command. The unattended vehicle passenger detection system may also have a camera with facial recognition capability, the camera being mounted within the interior compartment of the vehicle and communicatively coupled (either wired or wirelessly) to the control unit. The as unattended vehicle passenger detection system may also have a sound sensor that is capable of sensing a sound, the sound sensor being mounted within the interior compartment of the vehicle and communicatively coupled to the control unit. The unattended vehicle passenger detection system may also have a motion detector capable of sensing motion, the motion detector being mounted within the interior compartment of the vehicle and communicatively coupled to the control unit. Instead of issuing the first alarm command when the carbon dioxide detector detects elevated carbon dioxide levels within the vehicle, the unattended vehicle passenger detection system may wait for a confirmation from a second fault event prior to issuing the first alarm command, which second fault event includes the camera detecting a face within the interior compartment of the vehicle via its facial recognition capability, or the sound sensor detecting a sound within the interior compartment of the vehicle and the control unit determines that the sound detected is either a human cry or a dog bark or a cat meow, or the motion detector detecting a motion within the interior compartment of the vehicle. So that if upon the first threshold temperature being crossed within the interior compartment of the vehicle and the carbon dioxide detector detecting an increased carbon dioxide level within the interior compartment of the vehicle and at least one second fault event occurring, then the alarm system issues the first alarm command. As a further alternative, if upon the first threshold temperature being crossed within the interior compartment of the vehicle and the carbon dioxide detector not detecting an increased carbon dioxide level within the interior compartment of the vehicle yet at least one second fault event occurring, then the alarm system issues the first alarm command. The motion detector may be integrated within the camera or may be a standalone motion detector such as a passive infrared detector. The first alarm event may comprise an alarm speaker activation or may comprise a vehicle signal issued to the vehicle, which vehicle signal activates a light of the vehicle or activates an alarm of the vehicle or activates a horn of the vehicle (or some combination thereof) or may comprise a vehicle signal issued to the vehicle, which vehicle signal activates a window motor of the vehicle (rolls windows down) or activates an engine of the vehicle and also activates an HVAC system of the vehicle (turns air conditioning on if the temperature threshold exceeded is too high (vehicle too hot) or activates the heater if the temperature threshold is too low (vehicle too cold)) or may comprise a cellular telephone system message (telephone call with pre-recorded message or a text message, possibly with photographs or video from the camera, etc., and possibly with a GPS coordinate associated with the vehicle and provided by the control unit via a GPS chip onboard thereof) issued to at least one predetermined remote cellular telephone system recipient or some combination thereof. Optionally, after the first alarm command is issued, the temperature sensor continues to sense the temperature within interior compartment and if the temperature crosses a second predetermined threshold temperature which is outside the safe temperature range and the first predetermined threshold temperature is between the safe temperature range and the second threshold temperature, the control unit commands the alarm system to issue a second command in order to activate the second alarm, the second alarm triggering at least one second alarm event. In this situation, the first alarm event may comprise an alarm speaker activation or may comprise a vehicle signal issued to the vehicle, which vehicle signal activates a light of the vehicle or activates an alarm of the vehicle or activates a horn of the vehicle or may comprise a vehicle signal issued to the vehicle, which vehicle signal activates a window motor of the vehicle or activates an engine of the vehicle and activates an HVAC system of the vehicle or may comprise a cellular telephone system message (possibly with a GPS coordinate associated with the vehicle and provided by the control unit via a GPS chip onboard thereof) issued to at least one predetermined remote cellular telephone system recipient other than an emergency center (such as a 9-1-1 center or a dedicated emergency operations center for users of the present invention) or some combination thereof and the second alarm event can comprise any of the listed first alarm events that are not triggered by the first alarm command as well as a cellular telephone message, also with GPS coordinates, to an emergency center.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of the unattended vehicle passenger detection system of the present invention.
FIG. 2 is a perspective view of the control unit of the unattended vehicle passenger detection system.
FIG. 3 is an environmental view of the unattended vehicle passenger detection system mounted within a vehicle.
FIG. 4 is a schematic diagram of the alarm subsystem of the unattended vehicle passenger detection system.
Similar reference numerals refer to similar parts throughout the several views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, it is seen that the unattended vehicle passenger detection system of the present invention, generally denoted by reference numeral 10 , is comprised of a series of monitoring subsystems including a temperature (primary) sensor 12 , a CO 2 (carbon dioxide) sensor 14 , a sound sensor 16 , one or more motion sensors 18 , such as a short range passive infrared sensor 18 , and a day/night camera 20 . Other support subsystems include a control system 22 , data recorders 24 , cellular phone hardware 26 , a GPS chip 28 for reporting vehicle V location and an alarm control system 30 that triggers an appropriate alarm based on the situation.
The temperature sensor 12 monitors the temperature and possibly the humidity within the vehicle V and provides that data to the control system 22 .
The CO 2 sensor 14 measures the CO 2 levels within the vehicle V. These CO 2 levels are relayed to the control system 22 . Should a temperature fault occur (the temperature sensed by the temperature sensor 12 has crossed a predetermined threshold,) the control system 22 stores the current CO 2 level as a baseline CO 2 level. Thereafter, the CO2 sensor 14 continues to monitor the CO 2 level within the vehicle V and the control system 22 compares that data to the baseline CO 2 level.
The sound sensor 16 senses sounds within the vehicle V and the control system receives the sounds sensed and filters the sounds for specific sound wave patterns, such as a baby crying, a dog barking, or a cat meowing.
The motion sensor 18 senses for the presence of motion at a relatively short range so that motion outside of the vehicle V is not detected by the motion sensor 18 .
The camera 20 captures images, either still or video, or both, within the vehicle V and can also function as a motion sensor, in lieu of or in addition to the motion sensor 18 . Software associated with the camera 20 has facial recognition capabilities, as are well known in the art, enabling the camera 20 to determine whether a face is being detected within the camera's field of view. The field of view of the camera 20 is relatively small so that images outside of the vehicle V are not processed by the facial recognition software.
As seen, the various subsystems are held within a housing 32 that is mounted to the inside surface of the roof R of a vehicle V in appropriate fashion, such that the camera 20 and the motion sensor 18 have a field of view of the seat S or seats S where children C could be seated within the vehicle V. As seen, the housing 32 has other various components, such as a battery indicator 34 , an alarm indicator 36 , a power indicator 38 , a USB or similar port 40 for downloading data from the unattended vehicle passenger detection system 10 and uploading data, such as a call list as more fully explained below and software updates, etc., a reset button 42 , and a DC power connector 44 .
Electrical power can be provided to the unattended vehicle passenger detection system 10 internally by having a rechargeable battery 46 held within the housing 32 and electrically connected to the various components in the usual way. The rechargeable battery 46 is connected to the vehicle's electrical system by using a plug 48 that is plugged into a 12 volt DC receptacle in the normal fashion with a cord 50 connecting the plug 48 to the unattended vehicle passenger detection system's DC power connector 44 . Of course the cord 50 can be hidden within the vehicle V so as to not be unsightly and certainly so as not to hang down or otherwise become an obstacle to passengers within the vehicle V.
Alternately, the rechargeable battery 46 can be hardwire connected into the vehicle's electrical system via appropriate wiring (not illustrated). Advantageously, such hard wiring is to a constant on source of power, so that the unattended vehicle passenger detection system 10 receives 12 volt DC power regardless of whether the vehicle V is on or off. This may negate the need for an internal rechargeable battery, however, the presence of the rechargeable battery 46 in such an architecture acts as a backup power source should a problem arise within the vehicle's electrical system such as a blown fuse between the vehicle's electrical system and the unattended vehicle passenger detection system 10 . The unattended vehicle passenger detection system 10 has constant power because such power is needed in order to save a child C who enters the vehicle V that is turned off. The power consumption decreases to minimal levels when the vehicle V is turned off so as not to significantly drain the vehicle's battery.
In operation, the unattended vehicle passenger detection system 10 becomes armed whenever the unattended vehicle passenger detection system 10 determines that the vehicle V is turned from an on position to an off position. This determination can occur in one of many ways. If the battery 46 is connected to a 12 volt DC receptacle or if the battery 46 is hardwired to the vehicle's electrical system that receives electrical power only when the vehicle V is on, the control system 22 detects the loss of electrical power from the vehicle V and arms the unattended vehicle passenger detection system 10 , preferably after a short delay in order to give time for passengers of the vehicle V to exit the vehicle V. The unattended vehicle passenger detection system 10 can issue a chirp alarm through its alarm speaker 52 after a few seconds to serve as an initial warning to remind the driver and passengers of the unattended vehicle passenger detection system's presence so that the driver can see to the welfare of any children C (or pets) within the vehicle V. Should the unattended vehicle passenger detection system 10 begin to chirp or alarm while the driver or other responsible person is still in the vehicle V after the ignition is turned off, the individual can hit the reset button 42 . Hitting the reset button 42 delays the arming of the unattended vehicle passenger detection system 10 for a predetermined time. Once this time is expired, the unattended vehicle passenger detection system 10 becomes re-armed. Alternately, the unattended vehicle passenger detection system 10 can be programmed to read the wireless signals issued by the vehicle's FOB F so that when a door lock signal is issued by the FOB F, indicating that the driver has exited the vehicle V and has locked the doors D of the vehicle V, the unattended vehicle passenger detection system 10 becomes armed, becoming unarmed whenever a door unlock signal from the FOB F is received. Alternately, the unattended vehicle passenger detection system 10 can be hardwired to and integrated with the computer G of the vehicle V so that the computer G issues the vehicle V is off signal to the control system 22 of the unattended vehicle passenger detection system 10 .
When the unattended vehicle passenger detection system 10 becomes armed, the CO 2 sensor filters the CO 2 levels within the vehicle V and the unattended vehicle passenger detection system 10 otherwise remains idle until a temperature fault occurs, indicating that the temperature within the vehicle V is either too high or too low to be safe should a child C (or pet) be present in the vehicle V, as detected by the temperature sensor 12 . When a temperature fault occurs, the CO 2 sensor 14 takes a reading to establish a baseline CO 2 level within the vehicle V—this occurring immediately upon unattended vehicle passenger detection system 10 arming if the system became armed via the temperature fault arming method (system turns on due to temperature fault occurring). The CO 2 sensor 14 continues to monitor the CO 2 level within the vehicle V with the control system 22 comparing the continued readings of the CO 2 sensor 14 against the baseline reading taken when the temperature fault occurred. If the control system 22 determines that the CO 2 level, as read by the CO2 sensor 14 , within the vehicle V is increasing over a predetermined amount of time, indicating the presence of a living being within the vehicle V, the control system 22 issues an alarm command to the alarm system 30 which issues an alarm as more fully explained below.
This is the unattended vehicle passenger detection system 10 in its most basic configuration.
As with the CO 2 sensor 14 , each of the other sensors individually will cause the control system 22 to issue an alarm command to the alarm system 30 if a temperature fault occurs and their respective individual thresholds have been exceeded over a predetermined amount of time, as more fully explained below.
However, the unattended vehicle passenger detection system 10 can alarm (control system 22 to issue an alarm command to the alarm system 30 ) based on more than one sensor as a failsafe, so that if a temperature fault occurs, some combination of all the sensor subsystems can be used to determine whether a living being is present in the vehicle V prior to the control system 22 issuing the alarm command to the alarm system 30 . The threshold to alarm is lower if combinations (2 or more) of the various sensor subsystems have faulted indicating the presence of a living being within the vehicle V.
The motion sensor 18 monitors its field of view to determine whether it detects motion or not and sends its results to the control system 22 . Additionally, the sound sensor 16 intakes any sounds it hears and the control system 22 filters for specific sounds, namely a crying pattern, as almost all babies and toddlers will cry when subject to thermal danger, or an appropriate pet distress sound. The camera 20 is activated and its software determines whether a face is visible within the field of view of the camera 20 . If a face is detected, then this information is sent to the control system 22 . The camera's motion sensor capability can be used as an addition or an alternative to the motion sensor's capabilities to determine whether motion is present or not within the vehicle V. As such, if a temperature fault occurs, and the CO 2 levels are determined to be increasing within the vehicle V, then the control system 22 determines whether one of the other subsystems has returned a positive for living being presence within the vehicle V, either the motion sensor 18 and/or the camera 20 sensed motion within the vehicle V, or the sound system 16 detected a sound pattern consistent with a living being's presence within the vehicle V, or the camera 20 has detected a face within the vehicle V, then the control system 22 issues an alarm to the alarm system 30 .
As a further failsafe, if a temperature fault occurs, and the CO 2 level is not determined to be rising within the vehicle V—which can occur if the vehicle's inside fan is on but not cooling the vehicle V sufficiently, or the vehicle's windows are cracked sufficiently to move enough air including the CO 2 issued by the living being through the vehicle V—yet if two or more of the other subsystems return positives for the presence of a living being in the vehicle V—either the motion sensor 18 and/or the camera 20 detect motion within the vehicle V and the sound detector 16 captures sound consistent with a living being present in the vehicle, or the motion sensor 18 and/or the camera 20 detect motion within the vehicle V and the camera 20 detects a face within the vehicle V, or the sound detector 16 captures sound consistent with a living being present in the vehicle V and the camera 20 detects a face within the vehicle V—then the control system 22 issues an alarm command to the alarm system 30 in order to activate the alarm.
Activation of the alarm by the alarm system 30 can take several forms depending on the configuration of the unattended vehicle passenger detection system 10 . The alarm that is triggered can be as simple as an internal audible alarm 52 on the unattended vehicle passenger detection system 10 possibly with one or more flashing lights. While an 80 decibel alarm may frighten a child, especially in a closed vehicle V, the alternative is much worse. Alternately, or in addition, the alarm triggered can include use of the vehicle's alarm systems including sound the vehicle's onboard alarm A and/or honking the horn, and/or flashing the lights of the vehicle. The vehicle's alarm systems can be triggered via the FOB F method by having the unattended vehicle passenger detection system 10 mimic the FOB F and issue a panic code to the vehicle V or if the unattended vehicle passenger detection system 10 is integrated with the vehicle's computer G, by having the alarm system 30 issue such a command directly to the computer G. Additionally, if the FOB F of the vehicle V is so capable, or the unattended vehicle passenger detection system 10 is integrated with the vehicle's computer G, then the windows can be rolled down and/or the engine can be started and the HVAC system of the vehicle V can be started to either air condition the vehicle V if the temperature fault is a high temperature fault, or the heater is started if the temperature fault is a low temperature fault. Alternately, or in addition, cellular phone hardware can make a telephone call, send a text, and/or connect to a call center sending one or more photos or video clips of the interior of the vehicle V taken by the camera 20 as well as GPS coordinates. The unattended vehicle passenger detection system 10 can have the driver's and other emergency contact numbers preprogrammed into the unattended vehicle passenger detection system 10 at installation time or thereafter. With the GPS coordinates, as provided by the GPS unit 28 , also being included in the cell phone call, text, or call center connection, the vehicle's V location can be determined and passed on to appropriate first responders. The list of locations to which a call is placed or a text message is sent can include 9-1-1 and/or a dedicated support center.
The alarm that is triggered can also be staged so that the unattended vehicle passenger detection system 10 can have more than one temperature fault at each extreme. For example, on a high temperature fault, a lower level fault can be set at a temperature that is elevated, yet has not hit the real danger zone yet. If the control system 22 determines that a living being is present within the vehicle V as described above, then a lower level alarm, such as simply flashing the vehicle's lights and sounding its alarm A or horn can occur, and/or a cellular call is placed or a text message sent to every number on the call list except the dedicated emergency center or 9-1-1. However, once the higher temperature fault occurs—the temperature within the vehicle V is now reaching dangerous levels—then all available alarms are activated. Similarly, if the unattended vehicle passenger detection system 10 detects a temperature fault, yet only one of the subsystems detects the presence of a living being within the vehicle V, either the CO 2 level is rising within the vehicle V or motion is detected within the vehicle V or a living being made sound is detected within the vehicle V, or a face is detected within the vehicle V, then a lower level alarm can be triggered by the alarm system, however, if two or more of the subsystems detect the presence of a living being within the vehicle V, the alarms are triggered.
While the invention has been particularly shown and described with reference to an embodiment thereof, it will be appreciated by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention. | A system detects the presence of a living being within a vehicle and triggers an alarm should the temperature rise above or fall below a predetermined threshold limit. The system uses a carbon dioxide monitor to determine for the living being's presence, which is backed up by one or more subsystems that include a motion sensor that senses motion, a sound sensor that senses sounds, especially those made by distressed living beings, and a camera that uses facial recognition software to detect a face within the vehicle. The alarm can be staged so that a lower level of alarm is triggered when the hazardous temperature is approaching, but has not yet reached critical levels, and one of the subsystems has detected a living being within the vehicle, but the others have not yet activated, and a higher level alarm once critical temperatures have been reached. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of the filing date of U.S. provisional application no. 62/065,241, filed on Oct. 17, 2014, which is incorporated herein by reference in its entirety for all purposes.
BACKGROUND
[0002] 1. Field
[0003] In some aspects, the disclosure relates to electronics and, more specifically but not exclusively, to programmable non-volatile memory circuits.
[0004] 2. Related Art
[0005] This section introduces aspects that may help facilitate a better understanding of the disclosure. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is prior art or what is not prior art.
[0006] Non-volatile (NV) memory is used for configuration pattern storage for programmable logic devices such as field-programmable gate arrays (FPGAs). When this NV memory is external to the FPGA, the pattern is transferred to the FPGA's internal configuration static random-access memory (SRAM) through regular data pins. There are some product applications, however, where the NV memory block is internally embedded within the FPGA chip itself, so as to provide secure, independent configuration storage even when the FPGA is powered down. This memory pattern is normally transferred internally during chip power-up as an “initialization” sequence, with the data transfer most often taking place in the conventional fashion—as if the configuration pattern was externally presented to the FPGA's configuration controller even though the source is actually on chip.
SUMMARY
[0007] One aspect relates to a memory circuit comprising: a programmable non-volatile memory (NVM) cell configured to generate an NVM output signal indicative of a program state of the NVM cell comprising a first anti-fuse device (e.g., N 1 ), a first select device (e.g., N 2 ) connected in series with the first anti-fuse device at a first node, and a first pass device (e.g., N 5 ) and a programmable volatile memory (VM) cell configured to receive the NVM output signal at a VM input node and to generate a VM output signal indicative of the program state of the VM cell, wherein the first pass device is connected between the first node and the VM input nod.
[0008] A further aspect relates to a method for operating a memory circuit comprising configuring the VM cell by pre-programming the VM cell to have a first programmed state independent of the NVM output signal; and then configuring the VM cell using the NVM cell such that, when the NVM cell is not programmed, the NVM output signal does not change the VM cell from the first programmed state; and when the NVM cell is programmed, the NVM output signal does change the VM cell to a second programmed state different from the first programmed state.
[0009] A method can involve, prior to configuring the VM cell, programming the NVM cell by turning off the first pass device; and turning on the first select device to apply a programmable voltage level across a gate oxide layer of the first anti-fuse device to create a permanent breakdown path through the gate oxide layer of the first anti-fuse device. The method can involve programming by turning off the first select device applying a read voltage to a gate of the first anti-fuse device, and turning on the first pass device, such that, when the NVM cell is programmed, the voltage at the VM input node is changed using sufficient current flow through the gate oxide layer of the blown first anti-fuse device by an amount sufficient to flip the VM output signal.
[0010] An article of manufacture comprising an FPGA fabricated entirely in a standard CMOS process with distributed SRAM configuration cells where at least a subset of the SRAM configuration cells have an associated and local non-volatile memory cell that is capable of programming its associated SRAM cell.
[0011] A further aspect relates to a NV memory cell for loading configuration data into a respective cell of volatile configuration memory. The NV memory cell is provided with its respective cell of volatile configuration memory and comprises a programmable voltage divider comprising a pair of anti-fuse devices coupled in series, wherein in a first programmed state, an output node is driven by a shorted voltage applied to the output node of the NV memory cell through one of the pair of anti-fuse devices and is on one side of a common-mode voltage, and in a second programmed state, the output node is driven by a shorted voltage applied to the output node of the NV memory cell through the other anti-fuse device of the pair and is on the other side of the common-mode voltage for the NVM cell.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Embodiments and implementations of the disclosure will become more fully apparent from the following detailed description, the appended claims, and the accompanying drawings in which like reference numerals identify similar or identical elements.
[0013] FIG. 1 is a schematic circuit diagram of a memory circuit for storing at least one bit of information, according to one embodiment of the invention;
[0014] FIG. 2 is a set of waveforms representing a suitable sequence of voltages used to write and read a bit value into and out of the volatile memory (VM) cell of FIG. 1 ;
[0015] FIG. 3 is a set of waveforms representing a suitable sequence of voltages used to program a bit value into the non-volatile memory (NVM) cell of FIG. 1 ;
[0016] FIG. 4 is a set of waveforms representing a suitable sequence of voltages used to transfer the stored bit value from the programmed NVM cell to the VM cell of FIG. 1 ;
[0017] FIG. 5 is a schematic circuit diagram of a memory circuit for storing one bit of information, according to another embodiment of the invention;
[0018] FIG. 6 is a set of waveforms representing a suitable sequence of voltages used to program a bit value of 1 into (the previously unprogrammed) NVM cell of FIG. 5 ;
[0019] FIG. 7 is a set of waveforms representing a suitable sequence of voltages used to transfer the stored bit value from the NVM cell to the VM cell of FIG. 5 ;
[0020] FIG. 8 is a schematic circuit diagram of a memory circuit for storing up to two bits of information, according to another embodiment of the invention; and
[0021] FIG. 9 is a schematic circuit diagram of a memory circuit with enhanced testability, according to another embodiment of the invention.
DETAILED DESCRIPTION
[0022] Detailed illustrative embodiments of the present invention are disclosed herein. However, specific structural and functional details disclosed herein are merely representative for purposes of describing example embodiments of the present invention. The present invention may be embodied in many alternate forms and should not be construed as limited to only the embodiments set forth herein. Further, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments of the invention.
[0023] As used herein, the singular forms “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It further will be understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” specify the presence of stated features, steps, or components, but do not preclude the presence or addition of one or more other features, steps, or components. It also should be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may in fact be executed substantially concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0024] The time taken for initialization of an FPGA can be in the hundreds of milliseconds, especially for more-complex programmable devices. The latency incurred from this initialization delay can be detrimental to system operation. In addition, the energy (power times duration) of this initialization sequence can be so significant that power-reduction approaches, which include power-gating of the FPGA configuration storage, do not give a net improvement in energy usage, even at moderate power-cycle frequencies. Therefore, it is advantageous to utilize an approach which reduces both the power and the duration of this initialization process.
[0025] Current methods to reduce the initialization latency are generally based on parallelization of the transfer circuitry, which reduces the overall delay but does not affect the total energy and thus giving no advantage towards achieving power reduction during initialization. Moreover, the latency issue is improved, but not eliminated.
[0026] FIG. 1 is a schematic circuit diagram of a memory circuit 100 for storing at least one bit of information, according to one embodiment of the invention. Memory circuit 100 will typically be one of many instances of similar memory circuits distributed over an integrated circuit, such as an FPGA. As described in further detail below, various voltage signals are applied to the different input nodes of memory circuit 100 to selectively store one bit of information into the memory circuit and then subsequently read that stored bit of information from the memory circuit, where the bit of information is represented by the voltage levels at the output node Q, the complementary output node QB, and the read-sense node RS.
[0027] Depending on the logic applied downstream of the memory circuit 100 , a (relatively) high voltage level at node Q, a corresponding (relatively) low voltage level at node QB, and a corresponding (relatively) high voltage level at node RS may be interpreted as either a 1 or a 0, while the opposite voltage levels will be interpreted as the other bit value. For simplicity of description, the following discussion assumes that a bit value of 1 is represented by high voltages at nodes NV_OUT, Q, and RS, while a bit value of 0 is represented by low voltages at those nodes. Those skilled in that art will understand that an integrated circuit can be implemented using the complementary logic convention.
[0028] As shown in FIG. 1 , memory circuit 100 has two memory cells configured together: a programmable, differential, non-volatile memory (NVM) cell 110 and a programmable, volatile memory (VM) cell 120 , where VM cell 120 is an SRAM cell with a latch architecture. NVM cell 110 comprises N-type (e.g., transistor) devices N 1 -N 6 , while VM cell 120 comprises N-type (e.g., transistor) devices N 7 -N 9 , inverters INV 1 and INV 2 , and transmission gate TG. NVM cell 110 can be programmed to present either a (relatively) high voltage level (i.e., bit value 1) or a (relatively) low voltage level (i.e., bit value 0) at the NVM-cell output node NV_OUT. In particular, to program NVM cell 110 to present a high voltage level at node NV_OUT, a suitable sequence of programming voltages can be applied to (the previously unprogrammed) NVM cell 110 to result in a breakdown of the relatively thin gate oxide layer of anti-fuse device N 1 resulting in a permanent conduction path through that gate oxide layer. In that case, when a suitable sequence of transfer voltages are applied to NVM cell 110 , the output node NV_OUT will be driven high.
[0029] Alternatively, to program NVM cell 110 to present a low voltage level at node NV_OUT, a different, suitable sequence of programming voltages can be applied to (the previously unprogrammed) NVM cell 110 to result in a breakdown of the relatively thin gate oxide layer of anti-fuse device N 4 resulting in a permanent conduction path through that gate oxide layer. In that case, when the same, suitable sequence of transfer voltages are applied to NVM cell 110 , the output node NV_OUT will be driven low.
[0030] VM cell 120 can also be programmed to present either high voltage levels or low voltage levels at the VM-cell output nodes Q and RS and corresponding a low or high voltage level at the complementary VM-cell output node QB. In particular and for example, to program VM cell 120 to present a high voltage level (i.e., bit value 1) at node RS, a suitable sequence of write voltages can be applied to VM cell 120 to latch in a high voltage level at the input of inverter INV 1 . In that case, when a suitable sequence of read voltages are applied to VM cell 120 , the output node RS will be driven high.
[0031] Alternatively, to program VM cell 120 to present a low voltage level (i.e., bit value 0) at node RS, a different, suitable set of write voltages can be applied to VM cell 120 to latch in a low voltage level at the input of inverter INV 1 . In that case, when the same, suitable sequence of read voltages are applied to VM cell 120 , the output node RS will be driven low.
[0032] VM cell 120 can also be programmed by transferring the bit value stored in NVM cell 110 into VM cell 120 by applying a suitable sequence of transfer voltages to both NVM cell 110 and VM cell 120 . Note that the bit value transferred from NVM cell 110 into VM cell 120 can be subsequently changed by re-programming the VM cell 120 as described previously.
[0033] FIG. 2 is a set of waveforms representing a suitable sequence of voltages used to write and read a bit value into and out of VM cell 120 of FIG. 1 . In particular, the waveforms of FIG. 2 represent the following sequence of operations: (i) program VM cell 120 by writing a bit value of 0 into the VM cell, (ii) then read the stored bit value 0 from the VM cell, (iii) then reprogram the VM cell by writing a bit value of 1 into the VM cell, and (iv) then read the stored bit value 1 from the VM cell. During these operations, the (programmed or unprogrammed) NVM cell 110 is disabled and isolated from VM cell 120 by setting all of the following voltage levels low (e.g., to 0V): PROG_EN, COL_SEL_BAR, VP 1 , VP 2 , and LOAD.
[0034] In particular, as shown in FIG. 2 , at time t 0 , the integrated circuit is powered off and, at time t 1 , the integrated circuit is powered on with the power supply voltage VCC rising from 0V to its operating level. To store the bit value 0 into VM cell 120 , with the data voltage DATA and the latch voltage LATCH both low, the write-select voltage WRITE_SEL is driven high at time t 2 , which turns on the write device N 7 , which allows the low DATA voltage to appear at the input of inverter INV 1 . This, in turn, drives the output of inverter INV 1 (i.e., node QB) high and the output of inverter INV 2 (i.e., node Q) low. Prior to this time, the voltages at nodes QB and Q were indefinite.
[0035] At time t 3 , the latch voltage LATCH is driven high, which turns on the transmission gate TG, which enables the low voltage at node Q to be fed back to the input of inverter INV 1 . At time t 4 , the voltage WRITE_SEL is driven low, which turns off device N 7 and latches the bit value 0 into VM cell 120 .
[0036] To read the bit value 0 from VM cell 120 , at time t 5 , the read-select voltage READ_SEL is driven high, which turns on the read device N 8 . With node QB high, device N 9 will also be on, which drives node RS low. At time t 6 , the voltage READ_SEL is driven low, thereby ending this read operation of VM cell 120 . Note that, when READ_SEL is driven low, the read device N 8 is turned off, and node RS is driven high through resistor R 1 .
[0037] To re-program VM cell 120 to store the bit value 1, at time t 7 , the data voltage DATA is driven high, and, at time t 8 , the latch voltage LATCH is driven low to turn off the gate TG and isolate the input to inverter INV 1 from node Q. At time t 9 , the write-select voltage WRITE_SEL is driven high to turn on the write device N 7 and allow the high DATA voltage to appear at the input of inverter INV 1 . This, in turn, drives node QB low and node Q high. At time t 10 , the latch voltage LATCH is driven high to turn on gate TG and enable the high voltage at node Q to be fed back to the input of inverter INV 1 . At time t 11 , the voltage WRITE_SEL is driven low to turn off device N 7 and latch the bit value 1 into VM cell 120 .
[0038] To read the bit value 1 from VM cell 120 , at time t 12 , the read-select voltage READ_SEL is driven high, which turns on the read device N 8 . With node QB low, device N 9 will be off, which allows node RS to stay high. At time t 13 , the voltage READ_SEL is driven low, thereby ending this second read operation of VM cell 120 .
[0039] FIG. 3 is a set of waveforms representing a suitable sequence of voltages used to program a bit value into NVM cell 110 of FIG. 1 . During this operation, all of the following voltage levels are set low: DATA, LATCH, WRITE_SEL, READ_SEL, LOAD, and COL_SEL_BAR, such that the VM cell 120 is disabled and isolated from NVM cell 110 . Note that VM cell 120 does not have to be disabled in order to program NVM cell 110 ; it is sufficient for VM cell 120 to be isolated from NVM cell 110 .
[0040] FIG. 3 represents two different scenarios in a single timing diagram: (i) the waveforms for programming the NVM cell 110 to have a bit value of 1 (in which case, the first programming voltage VP 1 is driven high while the second programming voltage VP 2 remains low) and (ii) the waveforms for programming the NVM cell 110 to have a bit value of 0 (in which case, the first programming voltage VP 1 remains low while the second programming voltage VP 2 is driven high).
[0041] At time t 0 , the integrated circuit is powered off and, at time t 1 , the integrated circuit is powered on with the power supply voltage VCC rising from 0V to its operating level. At time t 2 , the program-enable voltage PROG_EN is driven high, which turns on access devices N 2 and N 3 . To store a bit value of 1 into NVM cell 110 , at time t 3 , the voltage VP 1 is driven to a high programming voltage level VPP, which is greater than VCC, while the voltage VP 2 remains low (not explicitly shown in FIG. 3 ). With VP 1 at VPP and VP 2 and COL_SEL_BAR both at 0V, the voltage across the gate oxide layer of anti-fuse device N 4 will be about 0V, while the voltage across the gate oxide layer of anti-fuse device N 1 will be about VPP, resulting in the permanent breakdown of that relatively thin gate oxide layer. At time t 4 , VP 1 is driven low, and, at time t 5 , PROG_EN is driven low, ending this particular programming operation. At this point, the anti-fuse device N 1 has been blown, and the NVM cell 110 has been permanently programmed with the bit value 1.
[0042] Alternatively, to store a bit value of 0 into NVM cell 110 , at time t 3 , VP 2 is driven to VPP, while VP 1 remains low (not explicitly shown in FIG. 3 ). In this case, with VP 2 at VPP and VP 1 and COL — SEL — BAR both at 0V, the voltage across the gate oxide layer of anti-fuse device N 1 will be about 0V, while the voltage across the gate oxide layer of anti-fuse device N 4 will be about VPP, resulting in the permanent breakdown of that relatively thin gate oxide layer. At time t 4 , VP 2 is driven low, and, at time t 5 , PROG_EN is driven low, ending this particular program operation. At this point, the anti-fuse device N 4 has been blown, and the NVM cell 110 has been permanently programmed with the bit value 0.
[0043] FIG. 4 is a set of waveforms representing a suitable sequence of voltages used to transfer the stored bit value from the programmed NVM cell 110 to VM cell 120 of FIG. 1 . During this operation, all of the following voltage levels are set low: PROG_EN, VP 2 , DATA, WRITE_SEL, READ_SEL, and COL_SEL_BAR, while VP 1 is at VCC. FIG. 4 presents two different waveforms for the voltage at node NV_OUT: (i) one for the situation in which device Ni was previously blown and (ii) another for the situation in which device N 4 was previously blown.
[0044] At time t 0 , the integrated circuit is powered off and, at time t 1 , the integrated circuit is powered on with the power supply voltage VCC rising from 0V to its operating level. At time t 2 , the transfer-enable voltage LOAD is driven high, which turns on transfer devices N 5 and N 6 . Prior to time t 2 , the voltage at node NV_OUT is indeterminate. After time t 2 , with devices N 5 and N 6 on, node NV_OUT will be driven either high or low depending on the programming of NVM cell 110 . In particular, if NVM cell 110 is programmed with a bit value 1, then node NV_OUT will be driven high through turned-on transfer device N 5 and the broken gate oxide layer of blown anti-fuse device N 1 . Alternatively, if NVM cell 110 is programmed with a bit value 0, then node NV_OUT will be driven low through turned-on transfer device N 6 and the broken gate oxide layer of blown anti-fuse device N 4 . At time t 3 , the voltage LATCH is driven high to turn on transmission gate TG and latch the transferred bit value into VM cell 120 . At time t 4 , LOAD is driven low, ending this transfer operation. At this point, the VM cell 120 is isolated from the NVM cell 110 and latched with the transferred bit value, which will appear at output node Q. Note that, to read the latched value at node RS, the read operation of FIG. 2 can be performed.
[0045] The various operations represented in FIGS. 2-4 can be used to perform various functions. At the time that the NVM cell 110 is programmed, it is desirable to verify that the desired bit value has been successfully stored in the NVM cell. As such, as soon as the program operation of FIG. 3 has been performed to program the NVM cell 110 , the transfer operation of FIG. 4 can be performed to transfer the stored bit value from the NVM cell 110 into the VM cell 120 , then the read operation of FIG. 2 can be performed to read the transferred bit value from the VM cell 120 at node RS, and then processing (e.g., external to memory circuit 100 ) can be performed to verify that the desired bit value has been successfully stored in the NVM cell 110 . Similarly, to verify that VM cell 120 is operating properly, the write and read operations operation of FIG. 2 can be performed intermittently to determine whether a single event upset (SEU) incident has occurred that changes the bit value stored in VM cell 120 .
[0046] Note that, in typical integrated circuits, the output nodes Q and QB will be used for on-line operations, while the output node RS will be reserved for circuit testing and programming verification.
[0047] Because the VM cell 120 can be isolated from the NVM cell 110 , the VM cell 120 can be selectively programmed and re-programmed both before and after an NVM-stored bit value has been transferred from the NVM cell 110 to the VM cell 120 . Furthermore, even after the VM cell 120 has been re-programmed to have a different bit value, the transfer operation can be repeated to re-program the VM cell 120 with the NVM-stored bit value. This functionality is useful in many integrated circuit applications.
[0048] On the other hand, there may be integrated circuits for which VM-programmability is not needed. In that case, it might not be necessary to be able to transfer and latch an NVM-stored bit value from NVM cell 110 into a volatile memory cell, like VM cell 120 , that can retain the value after the NVM cell 110 has been isolated. As such, in an alternative embodiment, some or all of the transmission gate TG and the devices N 7 -N 9 may be omitted. In that case, inverters INV 1 and INV 2 may be said to form volatile memory circuitry that is not a programmable VM cell per se. As such, after the NVM cell 110 has been programmed, as long as appropriate NVM transfer voltages are applied, the NVM-stored bit value will be continuously presented at the output node Q and its complement at the output node QB.
[0049] NVM cell 110 can be said to function as a programmable resistor-divider network. Before either N 1 or N 4 is blown, with transfer devices N 5 and N 6 on, the divided voltage at node NV_OUT will be midway between the voltages at VP 1 and VP 2 with both N 1 and N 4 functioning as capacitors. If N 1 is blown, then the divided voltage at node NV_OUT will shift towards the voltage at VP 1 with N 1 functioning as a resistor and N 4 still functioning as a capacitor. On the other hand, if instead N 4 is blown, then the divided voltage at node NV_OUT will shift towards the voltage at VP 2 with N 4 functioning as a resistor and N 1 still functioning as a capacitor.
[0050] Although memory circuit 100 has been described as storing either a bit value of 1 by blowing anti-fuse device N 1 or a bit value of 0 by blowing anti-fuse device N 4 , memory circuit 100 can also be operated in a different mode. In particular, memory circuit 100 can be programmed to store a first bit value by selectively blowing or not blowing anti-fuse device N 1 . At some later time, memory circuit 100 can be re-programmed to store a second bit value, independent of the first bit value, by blowing anti-fuse device N 1 (if it was not previously blown) and then selectively blowing or not blowing anti-fuse device N 4 . Note that this sequence can be reversed by storing the initial bit value using anti-fuse device N 4 and then the subsequent bit value using anti-fuse device N 1 .
[0051] When multiple instances of memory circuit 100 are used to store a single set of configuration data, such capability effectively squares the probability of a failure. In particular, if one of the memory circuits fails because its first anti-fuse device was not sufficiently blown, then all of the memory circuits can be programmed a second time using the other anti-fuse device. In that case, the programming of the second anti-fuse device will correct the faulty programming of the failed memory circuit and reinforce the programming of the remaining, correctly programmed memory circuits The chances of the same memory circuit being incorrectly programmed twice is the square of its chances of being incorrectly programmed the first time alone.
[0052] FIG. 5 is a schematic circuit diagram of a memory circuit 500 for storing one bit of information, according to another embodiment of the invention. Memory circuit 500 is analogous to memory circuit 100 of FIG. 1 , except that, instead of having the differential NVM cell 110 , memory circuit 500 has a single-sided NVM cell 510 comprising only devices N 1 , N 2 , and N 5 , which are similar to the corresponding devices in NVM cell 110 . The VM cell 520 of memory circuit 500 is identical to the VM cell 120 of FIG. 1 and can be written to and read from using the same waveforms of FIG. 2 .
[0053] Unlike NVM cell 110 of FIG. 1 , which has no default stored bit value, NVM cell 510 has a default stored bit value of 0 (i.e., corresponding to a relatively low voltage level at the NVM output node NV_OUT). As such, the programming of an “unprogrammed” NVM cell 110 involves the storing of a bit value of 1 into the NVM cell, in particular, by blowing the anti-fuse device N 1 by breaking its gate oxide layer.
[0054] FIG. 6 is a set of waveforms representing a suitable sequence of voltages used to program a bit value of 1 into (the previously unprogrammed) NVM cell 510 of FIG. 5 . During this operation, all of the following voltage levels are set low: DATA, LATCH, WRITE_SEL, READ_SEL, LOAD, and COLSELBAR, such that VM cell 520 is disabled and isolated from NVM cell 510 . Note that VM cell 520 does not have to be disabled in order to program NVM cell 510 ; it is sufficient for VM cell 520 to be isolated from NVM cell 510 .
[0055] At time t 0 , the integrated circuit is powered off and, at time t 1 , the integrated circuit is powered on with the power supply voltage VCC rising from 0V to its operating level. At time t 2 , the program-enable voltage PROG_EN is driven high, which turns on access device N 2 . At time t 3 , the program voltage VP 1 is driven to the high programming voltage level VPP. With VP 1 at VPP and COL — SEL — BAR at 0V, the voltage across the gate oxide layer of anti-fuse device N 1 will be about VPP, resulting in the permanent breakdown of that relatively thin gate oxide layer. At time t 4 , VP 1 is driven low, and, at time t 5 , PROG_EN is driven low, ending the program operation. At this point, the anti-fuse device N 1 has been blown, and the NVM cell 510 has been permanently programmed with the bit value 1.
[0056] FIG. 7 is a set of waveforms representing a suitable sequence of voltages used to transfer the stored bit value from NVM cell 510 to VM cell 520 of FIG. 5 . During this operation, all of the following voltage levels are set low: PROG_EN, DATA, READ_SEL, and COLSELBAR. Note that, because NVM cell 510 has a default stored bit value of 0, before the NVM-stored bit value is transferred from the NVM cell into VM cell 520 , the VM cell is “pre-programmed” to have the bit value 0. As such, if NVM cell 510 still has its default stored bit value of 0 (i.e., N 1 has not been blown), then, when the transfer operation of FIG. 7 is subsequently performed, VM cell 520 will retain its pre-programmed bit value of 0. If, however, NVM cell 510 has been programmed to have a stored bit value of 1 (i.e., N 1 has been blown), then, when the transfer operation of FIG. 7 is subsequently performed, the VM cell 520 will be re-programmed with a bit value of 1.
[0057] As in FIG. 4 , FIG. 7 presents two different waveforms for the voltage at node NV_OUT: one for the situation in which device N 1 was not previously blown (i.e., NVM cell 510 was not previously programmed and therefore retains its default bit value 0) and one for the situation in which device N 1 was previously blown (i.e., NVM cell 510 was previously programmed to store the bit value 1).
[0058] In particular, at time t 0 , the integrated circuit is powered off and, at time t 1 , the integrated circuit is powered on with the power supply voltage VCC rising from 0V to its operating level. At time t 2 , the voltage VP 1 is driven to the supply voltage level VCC. At time t 3 , the write-enable voltage WRITE_SEL is driven high, which will turn on write device N 7 . Prior to time t 3 , the voltage at the NVM-cell output node NV_OUT was indeterminate. Since DATA is low, turning on the write device N 7 drives the node NV_OUT low.
[0059] At time t 4 , the transfer-enable voltage LOAD is driven high, which turns on transfer device N 5 . At time t 4 , with device N 5 on, node NV_OUT will be driven depending on the programming of NVM cell 510 . In particular, if NVM cell 510 is not programmed (i.e., device N 1 is not blown), then the voltage at node NV_OUT will remain low. Alternatively, if NVM cell is programmed (i.e., device N 1 is blown), then the voltage at node NV_OUT will rise slightly but will remain relatively low due to the greater resistance of the blown device N 1 than the turned-on device N 7 .
[0060] At time t 5 , WRITE_SEL is driven low, thereby turning off device N 7 and isolating the node NV_OUT from the data signal DATA. If NVM cell 510 is not programmed, then the voltage at node NV_OUT will still remain low. Alternatively, if NVM cell 510 is programmed, then the voltage at node NV_OUT will begin to rise as charge flows through the blown device N 1 and the turned-on device N 5 to node NV_OUT. After a sufficient amount of time (t-delay), the voltage at node NV_OUT will have risen to a sufficiently high level to ensure that the data has been transferred from NVM cell 510 into VM cell 520 . After that time delay, at time t 6 , the latch signal LATCH is driven high to turn on the transmission gate TG and latch in the transferred bit value. During the first transfer after programming, in order to verify that the NVM cell 510 has been properly programmed, a margin may be subtracted from the t-delay value to decrease the programmed N 1 resistance required to properly sense and latch a bit value of 1.
[0061] At time t 7 , LOAD is driven low to isolate the VM cell 520 from the NVM cell 510 , and, at time t 8 , the voltage VCC can be removed from the gate of device N 1 , ending the transfer operation. At this point, the VM cell 120 is latched with the transferred bit value, which will appear at output node Q. Note that, to read the latched value at node RS, the read operation of FIG. 2 can be performed.
[0062] Similar to memory circuit 100 of FIG. 1 , the various operations represented in FIGS. 2, 6, and 7 can be used to perform similar functions for memory circuit 500 .
[0063] Note that, in alternative embodiments of memory circuits 100 and 500 , the series-connected transistors N 8 and N 9 may be connected to the node Q, instead of the node QB, with a corresponding inversion of the logic applied to interpret the corresponding voltage level.
[0064] A set of NVM cells, such as one or more instances of NVM cell 110 of FIG. 1 and/or one or more instances of NVM cell 510 of FIG. 5 , can be programmed to store configuration data for an integrated circuit, such as an FPGA. When the FPGA is initially powered up, the configuration data can be transferred from those NVM cells to corresponding VM cells. By distributing and co-locating instances of the NVM cells with corresponding instances of the VM cells throughout the FPGA, the amount of energy used during such configuration operations and the time that is takes to perform those operations can both be significantly lower than for comparable integrated circuits that use co-located arrays of NVM cells to store and transfer configuration data to distributed VM cells. As such, certain embodiments of this invention provide low-energy, distributed (zero-latency) NVM cells with minimal penalty in terms of both silicon area and process complexity. In general, memory circuits of the invention may provide one or more of the following advantages:
Differential comparison with unprogrammed NVM cell maximizes yield and system-level reliability; “Live at power-up” capability; Elimination of the power supply energy associated with initialization from a separate memory store; Power-gating of configuration bit cells without the penalty of re-initialization power and time; Compatibility with lower supply voltages (no retention issues); and Incremental extension to two or more configuration images which may be selected at run time.
[0071] FIG. 8 is a schematic circuit diagram of a memory circuit 800 for storing up to two bits of information, according to another embodiment of the invention. Memory circuit 800 is analogous to memory circuit 100 of FIG. 1 , except that, instead of having a single transfer-enable signal LOAD controlling both transfer devices N 5 and N 6 , NVM cell 810 of memory circuit 800 has two independent, transfer-enable signals LOAD 1 and LOAD 2 respectively controlling transfer devices N 5 and N 6 . The VM cell 820 of memory circuit 800 is identical to the VM cell 120 of FIG. 1 and can be written to and read from using the same waveforms of FIG. 2 . Memory circuit 800 can be used to independently store two different bit values: (1) a first bit value by selectively blowing or not blowing anti-fuse device N 1 and (2) a second bit value by selectively blowing or not blowing anti-fuse device N 4 .
[0072] FIG. 9 is a schematic circuit diagram of a memory circuit 900 with enhanced testability, according to another embodiment of the invention. Memory circuit 900 is analogous to memory circuit 100 of FIG. 1 , except that, instead of having a single program-enable signal PROG_EN controlling both access devices N 2 and N 3 , NVM cell 910 of memory circuit 900 has two independent, program-enable signals PROG_EN 1 and PROG_EN 2 respectively controlling access devices N 2 and N 3 . The VM cell 920 of memory circuit 900 is identical to the VM cell 120 of FIG. 1 and can be written to and read from using the same waveforms of FIG. 2 . Memory circuit 900 can be used to independently test the device chain of N 2 and N 5 from the device chain of N 3 and N 6 , by applying suitable voltages to PROG_EN 1 , PROG_EN 2 , and COL_SEL_BAR.
[0073] Although the invention has been described in the context of NVM cells that rely on anti-fuse devices to vary resistance levels, the invention can also be implemented in the context of NVM cells that rely on fuse devices to vary resistance levels. For example, suitable resistors that are susceptible to permanent electromigration when large voltage differentials are applied can be used as programmable devices in NVM cells of the invention. In either case, an NVM cell of the invention has one or more programmable devices that can be programmed to program a desired bit value into the NVM cell by varying one or more resistance levels in the NVM cell that alter the output voltage of the NVM cell that is presented during a transfer operation.
[0074] The invention has been described in the context of memory circuits implemented using N-type devices. Those skilled in the art will understand that the invention can also be implemented in the context of memory circuits implemented using P-type devices.
[0075] Memory circuits of the invention can be fabricated using the standard complementary metal-oxide semiconductor (CMOS) process flow and in particular one that does not have process steps for forming flash cells. Since the anti-fuse devices N 1 and N 4 function as programmable capacitors, the anti-fuse devices can be fabricated as either capacitors or MOS transistors. Similarly, access devices N 2 and N 3 and/or transfer devices N 5 and N 6 can be implemented using types of switches other than individual transistors. Note that, when transfer devices N 5 and N 6 are transistors, the LOAD voltage needs to be sufficiently greater than the supply voltage VCC applied to the anti-fuse devices N 1 and N 4 in order to turn on N 5 and N 6 . The devices described in this application can be manufactured with bulk CMOS technology, as well as silicon-on-insulator (SOI) technology.
[0076] Also for purposes of this description, the terms “couple,” “coupling,” “coupled,” “connect,” “connecting,” or “connected” refer to any manner known in the art or later developed in which energy is allowed to be transferred between two or more elements, and the interposition of one or more additional elements is contemplated, although not required. Conversely, the terms “directly coupled,” “directly connected,” etc., imply the absence of such additional elements.
[0077] Signals and corresponding terminals, nodes, ports, or paths may be referred to by the same name and are interchangeable for purposes here.
[0078] Transistors are typically shown as single devices for illustrative purposes. However, it is understood by those with skill in the art that transistors will have various sizes (e.g., gate width and length) and characteristics (e.g., threshold voltage, gain, etc.) and may consist of multiple transistors coupled in parallel to get desired electrical characteristics from the combination. Further, the illustrated transistors may be composite transistors.
[0079] Integrated circuits have become increasingly complex. Entire systems are constructed from diverse integrated circuit sub-systems. Describing such complex technical subject matter at an appropriate level of detail becomes necessary. In general, a hierarchy of concepts is applied to allow those of ordinary skill to focus on details of the matter being addressed.
[0080] Describing portions of a design (e.g., different functional units within an apparatus or system) according to functionality provided by those portions is often an appropriate level of abstraction, since each of these portions may themselves comprise hundreds of thousands, hundreds of millions, or more elements. When addressing some particular feature or implementation of a feature within such portion(s), it may be appropriate to identify substituent functions or otherwise characterize some sub-portion of that portion of the design in more detail, while abstracting other sub-portions or other functions.
[0081] A precise logical arrangement of the gates and interconnect (a netlist) implementing a portion of a design (e.g., a functional unit) can be specified. How such logical arrangement is physically realized in a particular chip (how that logic and interconnect is laid out in a particular design) may differ in different process technologies and/or for a variety of other reasons. Circuitry implementing particular functionality may be different in different contexts, and so disclosure of a particular circuit may not be the most helpful disclosure to a person of ordinary skill. Also, many details concerning implementations are often determined using design automation, proceeding from a high-level logical description of the feature or function to be implemented. In various cases, describing portions of an apparatus or system in terms of its functionality conveys structure to a person of ordinary skill in the art. As such, it is often unnecessary and/or unhelpful to provide more detail concerning a portion of a circuit design than to describe its functionality.
[0082] Functional modules or units may be composed of circuitry, where such circuitry may be fixed function, configurable under program control or under other configuration information, or some combination thereof. Functional modules themselves thus may be described by the functions that they perform, to helpfully abstract how some of the constituent portions of such functions may be implemented. In some situations, circuitry, units, and/or functional modules may be described partially in functional terms, and partially in structural terms. In some situations, the structural portion of such a description may be described in terms of a configuration applied to circuitry or to functional modules, or both.
[0083] Configurable circuitry is effectively circuitry or part of circuitry for each different operation that can be implemented by that circuitry, when configured to perform or otherwise interconnected to perform each different operation. Such configuration may come from or be based on instructions, microcode, one-time programming constructs, embedded memories storing configuration data, and so on. A unit or module for performing a function or functions refers, in some implementations, to a class or group of circuitry that implements the functions or functions attributed to that unit. Identification of circuitry performing one function does not mean that the same circuitry, or a portion thereof, cannot also perform other functions concurrently or serially.
[0084] Although circuitry or functional units may typically be implemented by electrical circuitry, and more particularly, by circuitry that primarily relies on transistors fabricated in a semiconductor, the disclosure is to be understood in relation to the technology being disclosed. For example, different physical processes may be used in circuitry implementing aspects of the disclosure, such as optical, nanotubes, micro-electrical mechanical elements, quantum switches or memory storage, magnetoresistive logic elements, and so on. Although a choice of technology used to construct circuitry or functional units according to the technology may change over time, this choice is an implementation decision to be made in accordance with the then-current state of technology.
[0085] Embodiments according to the disclosure include non-transitory machine readable media that store configuration data or instructions for causing a machine to execute, or for configuring a machine to execute, or for describing circuitry or machine structures (e.g., layout) that can execute or otherwise perform, a set of actions or accomplish a stated function, according to the disclosure. Such data can be according to hardware description languages, such as HDL or VHDL, in Register Transfer Language (RTL), or layout formats, such as GDSII, for example.
[0086] Unless explicitly stated otherwise, each numerical value and range should be interpreted as being approximate as if the word “about” or “approximately” preceded the value or range.
[0087] It will be further understood that various changes in the details, materials, and arrangements of the parts which have been described and illustrated in order to explain embodiments of this invention may be made by those skilled in the art without departing from embodiments of the invention encompassed by the following claims.
[0088] In this specification including any claims, the term “each” may be used to refer to one or more specified characteristics of a plurality of previously recited elements or steps. When used with the open-ended term “comprising,” the recitation of the term “each” does not exclude additional, unrecited elements or steps. Thus, it will be understood that an apparatus may have additional, unrecited elements and a method may have additional, unrecited steps, where the additional, unrecited elements or steps do not have the one or more specified characteristics.
[0089] The use of figure numbers and/or figure reference labels in the claims is intended to identify one or more possible embodiments of the claimed subject matter in order to facilitate the interpretation of the claims. Such use is not to be construed as necessarily limiting the scope of those claims to the embodiments shown in the corresponding figures.
[0090] Reference herein to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments necessarily mutually exclusive of other embodiments. The same applies to the term “implementation.”
[0091] The embodiments covered by the claims in this application are limited to embodiments that (1) are enabled by this specification and (2) correspond to statutory subject matter. Non-enabled embodiments and embodiments that correspond to non-statutory subject matter are explicitly disclaimed even if they fall within the scope of the claims. | One aspect relates to a memory circuit that has a programmable non-volatile memory (NVM) cell configured to generate an NVM output signal indicative of a program state of the NVM cell and to configure a volatile output based on the program state of the NVM cell. The NVM cell comprises a first anti-fuse device, a first select device connected in series with the first anti-fuse device at a first node, and a first pass device. The memory circuit also may have a programmable (independently of the NVM cell) volatile memory (VM) cell configured to receive the NVM output signal at a VM input node and to generate a VM output signal indicative of the program state of the VM cell. The NVM cell may have two NV elements that are separately programmable and are separately selectable via separate access transistors to drive the VM input node. | 6 |
FIELD OF THE INVENTION
The present invention relates to being able to selectively disable firearms of any type to prevent unauthorized persons from discharging the weapon.
BACKGROUND OF THE INVENTION
A number of prior devices have been disclosed which attempt to disable a weapon. Some of those are disclosed in U.S. Pat. Nos. 4,682,435 and each of the references cited therein.
With the rising crime rate and increase in population there has been a rise in the demand for firearms safety. One aspect of such safety is to prevent children from taking a weapon when not authorized to do so and accidentally discharging the weapon thereby causing injury to himself or another child or children. A second area of safety is the theft of weapons and their easy accessibility to be sold on the open market. A third area is when a peace officer attempts an arrest and a struggle ensues between the peace officers and a suspect who is being arrested wherein the officer is disarmed and his weapon is used against him. Several events including law enforcement officers have occurred over the past years in which the officer was wounded or killed with his own weapon and no one has been able to successfully prevent these events. To some degree even soldiers are subject to these types of events.
With the device disclosed in U.S. Pat. No. 4,682,435, when the weapon is removed from the possession of the authorized user, further active participation is required on his part to activate a separately carried transmitter which then disables the weapon from firing. In the case of an on going struggle involving a peace officer, soldier, etc. the time delay introduced by this extra action could prove fatal.
SUMMARY OF THE INVENTION
The present invention is directed at total disabling of the weapon when the weapon is not held by the designated person. Most modern weapons, whether a revolver or automatic, have a triggering mechanism which is mechanically activated by pulling on the trigger to a point where the trigger releases a firing mechanism such as a firing pin or hammer which then strikes the rear of the cartridge to discharge the weapon. This device seeks to actively block the movement of the trigger unless a specific chain of events occur.
The first embodiment of the invention incorporates recognition means within the cavity of the weapon which will recognize a code generating means delivered by the authorized user. In the case of hand guns the preferred authorized signal would be placed on the officers hand or finger and, would only be recognized when he had his hand on the grip of the weapon. This signal would then be detected by detector means and release the firing mechanism to allow discharge of the weapon.
This embodiment would be more specifically aimed at weapons carried by peace officers or even a soldier such that if the officer was disarmed by a suspect the weapon would not function since the officer's hand would not be about the weapon delivering a code to the detector means.
A second embodiment would allow the input of a specific code which would be recognized until deactivated manually or by a time elapse control. The second embodiment is aimed at the civilian use of sporting weapons such as rifles or shot guns.
The primary object of the invention is to disable a weapon until selectively enabled by an authorized person.
A further object of the invention is to prevent the unauthorized discharge of a fire arm thereby preventing injury and death.
Other and further objects of the invention become readily apparent from studying the detailed description which hereinafter follows.
BRIEF DESCRIPTION OF THE DRAWING
The following is a brief description of the drawings which are annexed hereto to form a portion of the description:
FIG. 1 is a side elevational view showing the silhouette of a typical weapon with a portion cut away to more clearly illustrate the functional device of the weapon and a schematic block diagram showing the functional portions of the invention.
FIG. 2 is a block diagram showing the electronic portions of the device.
Numeral references are used to designate like parts throughout the various figures of the drawing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a typical hand gun 1 which for purposes of this discussion is a semi-automatic pistol but this invention is not limited to that type of weapon and may be adapted to all types of weapons including electrical type weapons such as lasers, semi automatic pistols, automatic pistols, revolvers, rifles and shotguns of all types and models. The weapon 1 has a trigger 2 which would pivot about a pin 3. Means such as linkage 6 would allow a firing pin 5 to discharge the weapon upon pulling the trigger 2. The hand grip 7 is generally hollow except for a magazine to carry the ammunition and in some weapons may provide space for housing the safety device. Typically the hand 8 of the user would grip the hand grip 7 of the weapon 1 and place a finger through a trigger guard 9 in order to pull the trigger 2.
The safety device comprises trigger disabling means 20 such as a miniature normally closed solenoid having a plunger 21 which slides into opening 11 in the trigger 2. The trigger disable means 20 would be operably connected to a power source 22 such as a battery by electrical leads 23. The other side of the power source 24 would then be connected to recognition means and a circuit would be completed through line 25 to activate the trigger disabling means 20 and withdraw the plunger 21 from aperture 11 allowing the trigger mechanism to operate normally. The recognition means 26 provides energizing circuitry to energize the trigger disable means 20. The recognition means 26 is generally an electronic circuitry which would recognize a code or signal from the code detecting means 28. Typically the code detecting means 28 would read or receive a signal from a code generating means 30 which could be attached to the finger or palm of hand by means 32 such as, but not limited to, a band or palm glove which the user would wear such as those worn by golfers or the like.
The code generating means 30 may be of several configurations such as a micro chip which has a permanent magnetic code which would then be a by the code detecting means 28 and if the codes matched would allow the recognition means 26 to then activate the trigger disable means 20 to withdraw the plunger 21. The code generating means 30 may also be a bar code which would then be optically read by the detector means 28 or any other types of digitally or specifically generated code means which would then be recognized electronically by either an optical reader or receiver in detector code means 28. The primary function of the code generating means 30 is to provide a highly distinguishable signal which can only be detected when in close physical proximity with the code detecting means so that if the authorized person was not using the weapon or did not have his hand in a proper firing position the weapon could not be fired. Matching code generation means 30 may be worn on the left and right hand so that if the peace officer or user had to switch hands with the weapon 1 he could do so and the weapon 1 would still be operable.
The recognition means 26 could be generated by several means electronically such as a series of "and" and "nand" gates to generate a signal which would be then electronically amplified to generate an electrical pulse into the trigger disable means 20 to withdraw the pin 21. A locking circuit within the recognition means 26 would hold the pin 21 open until the code generating means 30 is withdrawn from the weapon 1.
An electrically fired weapon such as future types of lasers and/or electrically fired rocket pistols, the trigger disable means 20 would be an electrical interrupter circuit which would be normally open to prevent firing of the weapon unless a specified signal from the recognition means 26 closed the circuit thus allowing the weapon to fire.
FIG. 2 shows a block diagram of schematically how the device would work. Typically, a power source such as a battery which is rechargeable 32 would be operably connected through a thumb switch 34 which would supply power to the recognition means 26 which would then activate the trigger interrupt means 20. The code generation means 30 would provide the specific mechanism to allow the recognition means 26 to place the trigger interrupt means 20 in the firing position. Additionally, for safety purposes a low battery indicating means 36 could provide a visual means to signal a low battery and a test circuit such as test means 38 would provide an audio signal of a low battery to the user.
An alternate embodiment of the code generation means 30 would include a series of buttons such as normally open spring loaded switches which could be pushed in a sequential order to input a code or signal which would deactivate the trigger disable means to allow the weapon to be fired. The recognition means 30 would also include timer means such that when activated would permit operation of the firearm 1 for an predetermined amount of time. This feature would be helpful for use in sporting weapons. A second timing device, started by the action of mechanical code input, could be inserted into the circuitry which would shut down the circuit if the authorized code were not inputted within a specified time frame. This would prevent children, or others, from fiddling with the circuit long enough to accidentally hit upon the authorized code. The code generation means 30 includes a means to change the input code by a predetermined code to permit other users control of the weapon without disclosing the specific input code of the owner of the weapon.
Other and further embodiments of the safety device may be devised without departing from the spirit and scope of the invention herein described and the claims annexed hereto. | A safety device for firearms having trigger interrupting means operably connected to the trigger mechanism of the firearm. The code generating means worn by the user or operated by the user generates a signal which is detected by detection means on the weapon to disengage the trigger interrupting means to permit the weapon to selectively be fired by an authorized user. | 5 |
FIELD OF THE INVENTION
This invention relates to a fuel composition for internal combustion engines particularly characterized by corrosion inhibition.
BACKGROUND OF THE INVENTION
As is well known to those skilled in the art, fuel compositions typified by gasohol and alcohols which are to be considered for commercial use must possess low corrosion activity; and this may be effected by addition thereto of various corrosion inhibition systems. It is an object of this invention to provide a fuel composition for internal combustion engines particularly characterized by corrosion inhibition. Other objects will be apparent to those skilled in the art.
STATEMENT OF THE INVENTION
In accordance with certain of its aspects, the fuel composition of this invention may comprise
(a) a major portion of a fuel containing a hydrocarbon boiling in the gasoline boiling range plus optionally at least one alcohol selected from the group consisting of ethanol and methanol; and
(h) a minor corrosion inhibiting amount of, as a corrosion inhibiting agent, a dialkoxylated alkyl polyoxyalkyl primary amine ##STR3## wherein R is an alkyl group, R' and R" are divalent alkylene groups, x+y is 2-20 and a is 1-20.
DESCRIPTION OF THE INVENTION
The base fuel which is useful for employing the additive of the invention may be a motor fuel composition comprising a mixture of hydrocarbons boiling in the gasoline boiling range. This base fuel may contain straight chain or branch chain paraffins, cycloparaffins, olefins, and aromatic hydrocarbons and any mixture of these. The base fuel may be derived from straight-chain naphtha, polymer gasoline, natural gasoline, catalytically cracked or thermally cracked hydrocarbons, catalytically reformed stocks etc. It may typically boil in the range from about 80° to 450° F. Any conventional motor fuel base may be employed in the practice of this invention.
Gasohols may be employed typically containing 90-95 volume % of gasoline and 5-10 volume % methanol or ethanol. A typical gasohol contains 90 v % gasoline and 10 v % ethanol.
The fuel composition of the invention may contain any of the additives normally employed in a motor fuel. For example, the base fuel may be blended with anti-knock compounds, such as tetraalkyl lead compounds, including tetraethyl lead, tetramethyl lead, tetrabutyl lead, etc. or cyclopentadienyl manganese tricarbonyl generally in a concentration from about 0.05 to 4.0 cc. per gallon of gasoline. The tetraethyl lead mixture commercially available for automotive use contains an ethylene chloride-ethylene bromide mixture as a scavenger for removing lead from the combustion chamber in the form of a volatile lead halide. The motor fuel composition may also be fortified with any of the conventional additives including anti-icing additives, corrosion-inhibitors, dyes, etc.
In accordance with practice of this invention, there may be added to a major portion of the fuel, a minor corrosion-inhibiting amount of as a corrosion-inhibiting agent a dialkoxylated alkyl polyoxyalkyl primary amine ##STR4## wherein R is an alkyl group, R' and R" are divalent alkylene groups, x+y is 2-20 and a is 1-20.
In the above formula R may be an alkyl group typified by methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, amyls, hexyls, octyls, etc. R may contain 1-20 carbon atoms preferably 10-15, most preferably 10-12 carbon atoms.
R' and R" may be divalent alkylene groups containing 1-8 carbon atoms, typically 1-4, say 2-3 carbon atoms. Preferably R' is --C 3 H 4 and R" is ##STR5##
a may be 1-20, preferably 1-5, say 1-2. x may be 2-20, say 15.
Illustrative amines may be the following, the first being preferred:
TABLE______________________________________A.##STR6## x + y = 20B.##STR7## x + y = 15C.##STR8## x + y = 15D.##STR9##______________________________________
Commercially available compositions may be available under the trademark Jeffamine M-305, Jeffamine M-315, Jeffamine M-320, etc. One preferred commercially available produce may be the Jeffamine M-320 brand of ##STR10## wherein x+y=20.
These materials may be commercially available or they may be prepared as by diethoxylating the Jeffamine M-300 brand of amine ##STR11## This may be done by the following well-known series of reactions illustrating a typical synthesis: ##STR12##
In general, the additive of the invention is added to the base fuel in a minor corrosion-inhibiting amount, i.e. an amount effective to provide corrosion-inhibition to the fuel composition. The additive is highly effective in an amount ranging from about 0.0002 to 0.2 weight percent based on the total fuel composition. The concentration ranging from about 0.0008 to 0.01 weight percent is preferred with the most preferred concentration ranging from about 0.002 to 0.008 weight percent. Typically a concentration of 0.005 may be used.
It is a feature of this invention that the fuel composition so prepared is characterized by increased resistance to corrosion and rust i.e. by decreased ability to corrode or to form rust on iron-containing surfaces during operation of internal combustion engines.
The corrosive nature of the formulations may be tested by the Nace Rusting Test of the National Association of Corrosion Engineers. In this test, a mixture of 300 ml of test fuel and 30 ml distilled water is stirred at 100° F. (37.8° C.) with a steel specimen completely immersed therein for a test period of four hours. The percentage of the specimen that has rusted is noted.
When subjected to the NACE test, the motor fuel compositions of this invention generally show a rating of trace-to 1% rust.
DESCRIPTION OF PREFERRED EMBODIMENTS
Practice of this invention will be apparent to those skilled in the art from the following examples wherein, as elsewhere in this specification, all parts are parts by weight unless otherwise specified.
EXAMPLE I______________________________________ ##STR13## ##STR14## ##STR15## ##STR16## ##STR17## ##STR18##______________________________________
In this example which illustrates the best mode known to me of practicing the process of this invention, there is added to a reaction vessel 289.5 g (1 mole) of Jeffamine M-300 brand of (I) ##STR19## together with 200 g of diethylene glycol monomethyl ether solvent. The vessel is evacuated and flushed with nitrogen. Ethylene oxide (660 g; 15 moles) is passed in at 150° C./20 psig over 2 hours. The reaction mixture is diluted with an excess of water. Hydrochloric acid (aqueous) is added to lower the pH to about 11.
Product is II.
Water is removed by vacuum distillation followed by stripping at 165° C. under vacuum.
There is then added to the cooled reaction mixture 46 grams (2 moles) of sodium metal. After the sodium has completely reached to form III, as evidenced by stoppage of hydrogen generation, 220 g (5 moles) of ethylene oxide is passed into the reaction vessel at 50° C. for 2 hours. At the end of this time, the product is hydrolyzed by addition of 250 ml of aqueous hydrochloric acid.
The product is IV. ##STR20##
Water and solvent are removed by vacuum distillation followed by stripping at 165° C. under vacuum. The product is a liquid having a molecular weight of 949.5.
5 parts per thousand barrels (corresponding to 0.0019 w %) of this composition is added to a standard gasoline.
EXAMPLE II*
In this control example, the material tested is the standard gasoline with no additive.
The control and experimental gasolines are tested in the NACE test. Results are set forth in the Table which follows the Examples.
______________________________________NACE TEST RESULTSExample PTB % Rust______________________________________I 5 trace-1II* Control 0 50-100______________________________________
From this pair of comparative examples, it is apparent that the novel systems of this invention permit attainment of unexpected and superior results.
EXAMPLES I-IV
In these examples, the procedure of Example I was followed except that the charge amine was as follows:
TABLE______________________________________EXAMPLE AMINE______________________________________ (x + y = 15)III ##STR21##IV ##STR22## ##STR23##______________________________________
EXAMPLES V-VI
In these Examples the procedure of Example I was followed except that the amount of ethylene oxide was changed and the value of x+y was therefore different.
TABLE______________________________________ Ethylene OxideEXAMPLE moles x + y______________________________________VI 2 2VII 5 5VIII 10 10______________________________________
Although this invention has been illustrated by reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made which clearly fall within the scope of this invention. | A novel fuel composition containing a hydrocarbon boiling in the gasoline boiling range plus optionally ethanol or methanol plus, as a corrosion inhibitor, a dialkoxylated alkyl polyoxyalkyl primary amine ##STR1## typified by ##STR2## | 2 |
U.S. GOVERNMENT RIGHTS
[0001] The invention was made with U.S. Government support under Agreement No. N00421-02-3-3111 awarded by the Naval Air Systems Command. The U.S. Government has certain rights in the invention.
BACKGROUND OF THE INVENTION
[0002] The invention relates to nickel-base superalloys. More particularly, the invention relates to such superalloys used in high-temperature gas turbine engine components such as turbine disks and compressor disks.
[0003] The combustion, turbine, and exhaust sections of gas turbine engines are subject to extreme heating as are latter portions of the compressor section. This heating imposes substantial material constraints on components of these sections. One area of particular importance involves blade-bearing turbine disks. The disks are subject to extreme mechanical stresses, in addition to the thermal stresses, for significant periods of time during engine operation.
[0004] Exotic materials have been developed to address the demands of turbine disk use. U.S. Pat. No. 6,521,175 discloses an advanced nickel-base superalloy for powder metallurgical manufacture of turbine disks. The disclosure of the '175 patent is incorporated by reference herein as if set forth at length. The '175 patent discloses disk alloys optimized for short-time engine cycles, with disk temperatures approaching temperatures of about 1500° F. (816° C.). Other disk alloys are disclosed in U.S. Pat. No. 5,104,614, US2004221927, EP1201777, and EP1195446.
[0005] Separately, other materials have been proposed to address the demands of turbine blade use. Blades are typically cast and some blades include complex internal features. U.S. Pat. Nos. 3,061,426, 4,209,348, 4,569,824, 4,719,080, 5,270,123, 6,355,117, and 6706241 disclose various blade alloys.
SUMMARY OF THE INVENTION
[0006] One aspect of the invention involves a nickel-base composition of matter having a relatively high concentration of tantalum coexisting with a relatively high concentration of one or more other components.
[0007] In various implementations, the alloy may be used to form turbine disks via powder metallurgical processes. The one or more other components may include cobalt. The one or more other components may include combinations of gamma prime (γ′) formers and/or eta (η) formers.
[0008] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is an exploded partial view of a gas turbine engine turbine disk assembly.
[0010] FIG. 2 is a flowchart of a process for preparing a disk of the assembly of FIG. 1 .
[0011] FIG. 3 is a table of compositions of an inventive disk alloy and of prior art alloys.
[0012] FIG. 4 is an etchant-aided optical micrograph of a disk alloy of FIG. 3 .
[0013] FIG. 5 is an etchant-aided scanning electron micrograph (SEM) of the disk alloy of FIG. 3 .
[0014] FIG. 6 is a table of select measured properties of the disk alloy and prior art alloys of FIG. 3 .
[0015] Like reference numbers and designations in the various drawings indicate like elements.
DETAILED DESCRIPTION
[0016] FIG. 1 shows a gas turbine engine disk assembly 20 including a disk 22 and a plurality of blades 24 . The disk is generally annular, extending from an inboard bore or hub 26 at a central aperture to an outboard rim 28 . A relatively thin web 30 is radially between the bore 26 and rim 28 . The periphery of the rim 28 has a circumferential array of engagement features 32 (e.g., dovetail slots) for engaging complementary features 34 of the blades 24 . In other embodiments, the disk and blades may be a unitary structure (e.g., so-called “integrally bladed” rotors or disks).
[0017] The disk 22 is advantageously formed by a powder metallurgical forging process (e.g., as is disclosed in U.S. Pat. No. 6,521,175). FIG. 2 shows an exemplary process. The elemental components of the alloy are mixed (e.g., as individual components of refined purity or alloys thereof). The mixture is melted sufficiently to eliminate component segregation. The melted mixture is atomized to form droplets of molten metal. The atomized droplets are cooled to solidify into powder particles. The powder may be screened to restrict the ranges of powder particle sizes allowed. The powder is put into a container. The container of powder is consolidated in a multi-step process involving compression and heating. The resulting consolidated powder then has essentially the full density of the alloy without the chemical segregation typical of larger castings. A blank of the consolidated powder may be forged at appropriate temperatures and deformation constraints to provide a forging with the basic disk profile. The forging is then heat treated in a multi-step process involving high temperature heating followed by a rapid cooling process or quench. Preferably, the heat treatment increases the characteristic gamma (γ) grain size from an exemplary 10 μm or less to an exemplary 20-120 μm (with 30-60 μm being preferred). The quench for the heat treatment may also form strengthening precipitates (e.g., gamma prime (γ′) and eta (η) phases discussed in further detail below) of a desired distribution of sizes and desired volume percentages. Subsequent heat treatments are used to modify these distributions to produce the requisite mechanical properties of the manufactured forging. The increased grain size is associated with good high-temperature creep-resistance and decreased rate of crack growth during the service of the manufactured forging. The heat treated forging is then subject to machining of the final profile and the slots.
[0018] Whereas typical modern disk alloy compositions contain 0-3 weight percent tantalum (Ta), the inventive alloys have a higher level. This level of Ta is believed unique among disk alloys. More specifically, levels above 3% Ta combined with relatively high levels of other γ′ formers (namely, one or a combination of aluminum (Al), titanium (Ti), niobium (Nb), tungsten (W), and hafnium (Hf)) and relatively high levels of cobalt (Co) are believed unique. The Ta serves as a solid solution strengthening additive to the γ′ and to the γ. The presence of the relatively large Ta atoms reduces diffusion principally in the γ′ phase but also in the γ. This may reduce high-temperature creep. Discussed in further detail regarding the example below, a Ta level above 6% in the inventive alloys is also believed to aid in the formation of the η phase and insure that these are relatively small compared with the γ grains. Thus the η precipitate may help in precipitation hardening similar to the strengthening mechanisms obtained by the γ′ precipitate phase.
[0019] It is also worth comparing the inventive alloys to the modern blade alloys. Relatively high Ta contents are common to modern blade alloys. There may be several compositional differences between the inventive alloys and modern blade alloys. The blade alloys are typically produced by casting techniques as their high-temperature capability is enhanced by the ability to form very large polycrystalline and/or single grains (also known as single crystals). Use of such blade alloys in powder metallurgical applications is compromised by the formation of very large grain size and their requirements for high-temperature heat treatment. The resulting cooling rate would cause significant quench cracking and tearing (particularly for larger parts). Among other differences, those blade alloys have a lower cobalt (Co) concentration than the exemplary inventive alloys. Broadly, relative to high-Ta modern blade alloys, the exemplary inventive alloys have been customized for utilization in disk manufacture through the adjustment of several other elements, including one or more of Al, Co, Cr, Hf, Mo, Nb, Ti, and W. Nevertheless, possible use of the inventive alloys for blades, vanes, and other non-disk components can't be excluded.
[0020] Accordingly, the possibility exists for optimizing a high-Ta disk alloy having improved high temperature properties (e.g., for use at temperatures of 1200-1500° F. (649-816° C.) or greater). It is noted that wherever both metric and English units are given the metric is a conversion from the English (e.g., an English measurement) and should not be regarded as indicating a false degree of precision.
EXAMPLE
[0021] Table I of FIG. 3 below shows a specification for one exemplary alloy or group of alloys. The nominal composition and nominal limits were derived based upon sensitivities to elemental changes (e.g., derived from phase diagrams). The table also shows a measured composition of a test sample. The table also shows nominal compositions of the prior art alloys NF3 and ME16 (discussed, e.g., in U.S. Pat. No. 6,521,175 and EP1195446, respectively). Except where noted, all contents are by weight and specifically in weight percent.
[0022] The most basic η form is Ni 3 Ti. It has generally been believed that, in modern disk and blade alloys, η forms when the Al to Ti weight ratio is less than or equal to one. In the exemplary alloy, this ratio is greater than one. From compositional analysis of the n phase, it appears that Ta significantly contributes to the formation of the η phase as Ni 3 (Ti, Ta). A different correlation (reflecting more than Al and Ti) may therefore be more appropriate. Utilizing standard partitioning coefficients one can estimate the total mole fraction (by way of atomic percentages) of the elements that substitute for atomic sites normally occupied by Al. These elements include Hf, Mo, Nb, Ta, Ti, V, W and, to a smaller extent, Cr. These elements act as solid solution strengtheners to the γ′ phase. When the γ′ phase has too many of these additional atoms, other phases are apt to form, such as n when there is too much Ti. It is therefore instructive to address the ratio of Al to the sum of these other elements as a predictive assessment for n formation. For example, it appears that η will form when the molar ratio of Al atoms to the sum of the other atoms that partition to the Al site in γ′ is less than or equal to about 0.79-0.81. This is particularly significant in concert with the high levels of Ta. Nominally, for NF3 this ratio is 0.84 and the Al to Ti weight percent ratio is 1.0. For test samples of NF3 these were observed as 0.82 and 0.968, respectively. The η phase would be predicted in NF3 by the conventional wisdom Al to Ti ratio but has not been observed. ME16 has similar nominal values of 0.85 and 0.98, respectively, and also does not exhibit the η phase as would be predicted by the Al to Ti ratio.
[0023] The η formation and quality thereof are believed particularly sensitive to the Ti and Ta contents. If the above-identified ratio of Al to its substitutes is satisfied, there may be a further approximate predictor for the formation of η. It is estimated that η will form if the Al content is less than or equal to about 3.5%, the Ta content is greater than or equal to about 6.35%, the Co content is greater than or equal to about 16%, the Ti content is greater than or equal to about 2.25%, and, perhaps most significantly, the sum of Ti and Ta contents is greater than or equal to about 8.0%.
[0024] In addition to substituting for Ti as an η-former, the Ta has a particular effect on controlling the size of the η precipitates. A ratio of Ta to Ti contents of at least about three may be effective to control η precipitate size for advantageous mechanical properties.
[0025] FIGS. 4 and 5 show microstructure of the sample composition reflecting atomization to powder of about 74 μm (0.0029 inch) and smaller size, followed by compaction, forging, and heat treatment at 1182° C. (2160° F.) for two hours and a 0.93-1.39° C./s (56-83° C./minute (100-150° F./minute)) quench. FIG. 4 shows η precipitates 100 as appearing light colored within a γ matrix 102 . An approximate grain size is 30 μm. FIG. 5 shows the matrix 102 as including much smaller γ′ precipitates 104 in a γ matrix 106 . These micrographs show a substantially uniform distribution of the η phase. The η phase is no larger than the γ grain size so that it may behave as a strengthening phase without the detrimental influence on cyclic behavior that would occur if the η phase were significantly larger.
[0026] FIG. 5 shows the uniformity of the γ′ precipitates. These precipitates and their distribution contribute to precipitation strengthening. Control of precipitate size (coarsening) and spacing may be used to control the degree and character of precipitate strengthening. Additionally, along the η interface is a highly ordered/aligned region 108 of smaller γ′ precipitates. These regions 108 may provide further impediments to dislocation motion. The impediment is a substantial component of strengthening against time-dependent deformation, such as creep. The uniformity of the distribution and very fine size of the γ′ in the region 108 indicates this is formed well below the momentary temperatures found during quenching.
[0027] Alloys with a high γ′ content have been generally regarded as difficult to weld. This difficulty is due to the sudden cooling from the welding (temporary melting) of the alloy. The sudden cooling in high γ′ alloys causes large internal stresses to build up in the alloy leading to cracking.
[0028] The one particular η precipitate enlarged in FIG. 5 has an included carbide precipitate 120 . The carbide is believed primarily a titanium and/or tantalum carbide which is formed during the solidification of the powder particles and is a natural by-product of the presence of carbon. The carbon, however, serves to strengthen grain boundaries and avoid brittleness. Such carbide particles are extremely low in volume fraction, extremely stable because of their high melting points and believed not to substantially affect properties of the alloy.
[0029] As noted above, it is possible that additional strengthening is provided by the presence of the η phase at a size that is small enough to contribute to precipitate phase strengthening while not large enough to be detrimental. If the η phase were to extend across two (or more) grains, then the dislocations from deformation of both grains would be more than additive and therefore significantly detrimental, (particularly in a cyclic environment). Exemplary η precipitates are approximately 2-14 μm long in a field of 0.2 μm cooling γ′ and an average grain diameter (for the γ) of 30-45 μm. This size is approximately the size of large γ′ precipitates as found in conventional powder metallurgy alloys such as IN100 and ME16. Testing to date has indicated no detrimental results (e.g., no loss of notch ductility and rupture life).
[0030] Table II of FIG. 6 shows select mechanical properties of the exemplary alloy and prior art alloys. All three alloys were heat treated to a grain size of nominal ASTM 6.5 (a diameter of about 37.8 μm (0.0015 inch)). All data were taken from similarly processed subscale material (i.e., heat treated above the γ′ solvus to produce the same grain size and cooled at the same rate). The data show a most notable improvement in quench crack resistance for the inventive alloys. It is believed that the very fine distribution of γ′ in the region 108 around the η precipitate (which γ′ precipitates do not form until very low temperatures are reached during the quench cycle) are participating in the improved resistance to quench cracking. A lack of this γ′ around the η might encourage the redistribution of the stresses during the quench cycle to ultimately cause cracking.
[0031] From Table II it can be seen that, for equivalent grain sizes, the sample composition has significant improvements at 816° C. (1500° F.) in time dependent (creep and rupture) capability and yield and ultimate tensile strengths. At 732° C. (1350° F.) the sample composition has slightly lower yield strength than NF3 but still significantly better than ME16. Further gains in these properties might be achieved with further composition and processing refinements.
[0032] A test has been devised to estimate relative resistance to quench cracking and results at 1093° C. (2000° F.) are also given in Table II. This test accounts for an ability to withstand both the stresses and strains (deformation) expected with a quench cycle. The test is dependent only on the grain size and the composition of the alloy and is independent of cooling rate and any subsequent processing schedule. The sample composition showed remarkable improvements over the two baseline compositions at 1093° C. (2000° F.).
[0033] Alternative alloys with lower Ta contents and/or a lack of n precipitates may still have some advantageous high temperature properties. For example, lower Ta contents in the 3-6% range or, more narrowly the 4-6% range are possible. For substantially η-free alloys, the sum of Ti and Ta contents would be approximately 5-9%. Other contents could be similar to those of the exemplary specification (thus likely having a slightly higher Ni content). As with the higher Ta alloys, such alloys may also be distinguished by high Co and high combined Co and Cr contents. Exemplary combined Co and Cr contents are at least 26.0% for the lower Ta alloys and may be similar or broader (e.g., 20.0% or 22.0%) for the higher Ta alloys.
[0034] One or more embodiments of the present invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, the operational requirements of any particular engine will influence the manufacture of its components. As noted above, the principles may be applied to the manufacture of other components such as impellers, shaft members (e.g., shaft hub structures), and the like. Accordingly, other embodiments are within the scope of the following claims. | A composition of matter comprises, in combination, in weight percent: a largest content of nickel; at least 16.0 percent cobalt; and at least 3.0 percent tantalum. The composition may be used in power metallurgical processes to form turbine engine turbine disks. | 2 |
This is a continuation of application Ser. No. 07/503,419, filed Apr. 2, 1990, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to the field of semiconductor devices and their manufacture. More specifically, in one embodiment the invention provides bipolar devices having high breakdown voltages.
Bipolar devices such as those of the present invention are commonly combined with other devices such as a p-channel metal-oxide semiconductor (PMOS). In one embodiment, PMOS devices are fabricated along with n-channel metal-oxide semiconductors (NMOS) devices to produce complementary metal-oxide semiconductor (CMOS) devices. Bipolar and CMOS devices are fabricated together to produce "BiCMOS" devices. BiCMOS devices offer the advantages of the high packing density and low power consumption of CMOS devices, as well as the high speed of bipolar devices. One BiCMOS device and process for fabrication thereof is described in U.S. Pat. No. 4,764,480 (Vora), assigned to the assignee of the present invention and incorporated herein by reference for all purposes.
One form of a bipolar device is a lateral PNP bipolar device. A common use of such a bipolar lateral device is as a voltage clamping device in programmable logic array (PLA) circuits. Programmable logic array circuits are programmed by providing a reverse bias voltage sufficiently high to program a vertical fuse or lateral fuse in components of the circuitry. However, it is desired that the voltage clamping devices be left unaffected by the reverse bias voltage during programming. Thus, the voltage clamping devices in PLA circuits must withstand a collector-to-emitter reverse bias voltage which is sufficient to program vertical fuse or lateral fuse devices. For this reason, it would be advantageous for a bipolar lateral devices to have a BV ceo value greater than the reverse bias voltage used to program a PLA circuit.
SUMMARY OF THE INVENTION
The present invention includes recognition of certain problems encountered in previous devices. Previous single polysilicon processes have resulted in bipolar lateral transistors in which the BV ceo of the bipolar lateral device is clamped at about 5.8 V. However, this value is equal to or close to the BV ebo value of a standard vertical bipolar device. Accordingly, it is desirable to produce a bipolar lateral device, which has an increased BV ceo , such as, for example a BV ceo greater than about 5.8 volts. According to one embodiment of the invention, a bipolar lateral PNP device is provided which has BV ceo of, for example, greater than about 5.8 volts, preferably greater than or equal to about 8 volts. According to a second embodiment, a bipolar lateral device is provided which has a BV ceo of, for example, greater than or equal to about 20 volts. By providing such high-BV ceo bipolar lateral devices, it is possible to obtain voltage clamping functions which are not affected by the reverse bias voltage used in programming a PLA circuit.
The bipolar devices disclosed herein can be fabricated in combination with CMOS devices to produce an improved BiCMOS device. The invention provides devices which have improved performance, reduced size, and/or which may be fabricated more quickly and economically.
In one embodiment the invention comprises doping regions of a semiconductor to produce collector, emitter, and base regions. Polysilicon is positioned on the surface of the substrate adjacent the collector, emitter, and base regions. The polysilicon adjacent the collector and emitter regions is doped with a dopant of a first conductivity type and polysilicon adjacent the base is doped with a dopant of a second conductivity type. Metal silicide is formed over the polysilicon adjacent the collector and emitter while the polysilicon adjacent the base is free of metal silicide. The device has a BV ceo of at least about 8 V, preferably at least about 10 V. In another embodiment, the device is formed in substantially the same manner except that the polysilicon which is adjacent the base region is provided in a substantially intrinsic state. In this embodiment, the device preferably has a BV ceo of at least about 20 V.
A further understanding of the nature and advantages of the inventions herein may be realized by reference to the remaining portions of the specification and the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a cross-section of a bipolar structure according to first embodiment of the invention with the polysilicon over the base being n type;
FIG. 1B is a cross-section of a bipolar structure according to a second embodiment of the invention with the polysilicon over the base being intrinsic;
FIGS. 2A to 2L illustrate fabrication of the bipolar device according to a first embodiment of the invention;
FIGS. 3A to 3J correspond to FIGS. 2C-2L, but show fabrication of a bipolar device according to a second embodiment of the invention;
FIG. 4A depicts current versus voltage for a first device;
FIG. 4B depicts current versus voltage for a device according to the present invention with the n+ polysilicon overlying the base being unsilicided;
FIG. 4C depicts current versus voltage for a device according to the present invention with intrinsic, unsilicided polysilicon overlying the base; and
FIGS. 5 and 6 depict current gain versus collector current for devices according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Contents
I. General
II. Fabrication Sequence of Bipolar Devices
III. Device Performance
I. General
FIG. 1A illustrates a bipolar device in cross-section according to one embodiment of the invention. The device includes a bipolar transistor 2 (which in the embodiment shown in FIG. 1 is a lateral PNP transistor). The device is fabricated on a substrate 10 which includes a single-crystal body 10a and an epitaxial layer 11. In the embodiment shown in FIG. 1 the substrate is a p-substrate having a dopant concentration of between about 1×10 13 and 1×10 16 with a preferred range of between about 2×10 14 and 3×10 15 /cm 3 . The reduced pressure doped n-type epitaxial silicon 11 is grown on top of the single-crystal body 10a. The devices are fabricated within the epitaxial layer 11.
The transistor 2 is provided with a heavily doped buried layer 16 and sink 17, which together provide a low resistance connection region between a base contact 20 and the base 21. In preferred embodiments the buried layer 16 and sink 17 are doped to a concentration of between about 1×10 17 and 1×10 20 with a preferred range of about 5×10 18 to 1×10 20 /cm 3 . The base region 21 has a dopant concentration preferably about 1×10 16 .
P-doped regions 74, 76 formed in the epitaxial layer 11 act as the emitter and collector of a lateral PNP device. A lightly-doped n-type diffused region 27a is formed between the emitter 74 and the collector 76 as a result of down-diffusion from the n+ doped polysilicon region 27 during processing.
A well-known p+ channel stop 19 is provided between the transistor and adjacent devices to prevent surface inversion of the lightly doped substrate which would short circuit the buried layer 16 with adjacent devices. Between the transistor 2 and adjacent devices, oxide isolation regions 22a, 22b, and 22d, which typically will be SiO 2 are provided for device isolation. Viewed from the top of the structure, these oxide isolation regions connect to each other to form annular bands around the active device areas.
Along the surface of the device are polycrystalline silicon (polysilicon) regions forming, a resistor 24, emitter contact 26, which also functions as an end contact portion of the resistor 24, a polysilicon region 27 overlying the base 27a, a collector contact 26' and base contact 20. Sidewall oxide 44 is provided on the sidewalls of the polysilicon 27 which overlies the base. The polysilicon resistor 24, emitter contact 26, polysilicon adjacent the base 27, collector contact 26', and base contact 20 are formed from a single layer of deposited polysilicon which is doped and etched as described more fully below.
Refractory metal silicide contacts 46a, 46b are formed on the upper surface and sidewall surface of the collector contact 26. Silicide 46c is formed on the surface of the epitaxial region adjacent the collector 74 and extends to the sidewall oxide 44. Preferably, the collector contact silicide layers 46a, 46b, 46c are continuous. Similarly, refractory metal silicide contacts 46f, 46e are formed on the upper surface and sidewall surface of the emitter contact 26'. Silicide 46d is formed on the surface of the epitaxial region adjacent the emitter 76. Preferably, the emitter contact silicide 46d, 46e, 46f is continuous. Silicide 46g, 46h is formed on the upper surface and sidewall surface respectively, of the base contact 20. Silicide 46i is also formed on the upper surface of the p+ doped polysilicon 24' which forms the end contact portion of the resistor 24 opposite the emitter contact 26. The refractory metal contacts shown herein reduce the resistivity of the adjacent poly contacts and, therefore, increase the speed of the device.
The structure further includes a thick (0.8 to 1.3 and preferably about 1.3 μm) oxide layer 56 to insulate the devices from metal layer 58, used for interconnection purposes. Metal contacts similar to the contacts 58 shown can also be provided for, e.g., connecting to the polysilicon overlying the base (the base contact) 27, but are not seen in the particular cross-section shown.
FIG. 1B illustrates a bipolar device in cross-section according to a second embodiment of the invention. FIG. 1B is similar to FIG. 1A except that the polysilicon overlying the base, 27', is intrinsic, rather than n+ type and, consequently, there is no region corresponding to region 27a of FIG. 1A, since there will be no down-diffusion from the intrinsic polysilicon 27'.
II. Fabrication Sequence of Bipolar Devices
FIGS. 2A through 2N illustrate fabrication of the bipolar device shown in FIG. 1A. In particular, FIG. 2A illustrates a cross-section of the devices at a first stage of their fabrication. To reach this stage, the single-crystal body 10a was masked for formation of the buried layer 16 with arsenic, antimony, or the like. The implant energy used for formation of region 16 is preferably about 50 to 100 keV with a preferred range of between about 70 to 80 keV such that the dopant concentration of region 16 is between about 5×10 17 to 2×10 20 with a preferred range of between about 1×10 19 and 1×10 20 /cm 3 .
After formation of the n+ region 16, the device is then masked for formation of the p+ channel stop 19. The implant energy used in formation of the region 19 is preferably between about 10 and 200 keV with a preferred range of 50 to 150 keV such that the dopant concentration of the p+ buried layers is between about 1×10 17 and 1×10 18 /cm 3 . The p+ region preferably is doped with boron.
The buried layer/channel stop mask is then removed and, using well-known techniques, a reduced pressure, n-type epitaxial silicon layer 11 having a thickness of about 1.1 μm is grown across the surface of the single-crystal body 10a. After depositing sandwiched layers of oxide and nitride, a photoresist mask is then formed over the surface so as to define field oxide regions 22a, 22b and 22d. The oxide regions are formed using a modified sidewall masked isolation ("SWAMI") process. The SWAMI process is described, e.g., in Chin, et al IEEE Transactions on Electron Devices, Vol ED-29, No. 4, April 1982, pp. 536-540. In some embodiments, the process is modified as described in co-pending application Ser. No. 07/502,943 incorporated by reference.
Thereafter, a grown screen oxide layer having a thickness of about 250 Å is formed on the surface of the substrate and a mask is formed, exposing only the sink region 17. A sink implant using an implant energy of about 100 and 190 keV with a dose of between about 1×10 14 and 1×10 16 using phosphorus as a dopant. The resulting dopant concentration in the sink region 17 is between about 1×10 19 and 1×10 20 /cm 3 . The sink is then annealed and driven-in by heating with a conventional thermal cycle in nitrogen.
FIG. 2b illustrates the next sequence of process steps. A layer of intrinsic polysilicon 64 having a thickness of about 1,000 to 4,000 and preferably about 3,200 Å is deposited across the surface of the substrate and a cap oxide layer 66 is formed by thermal oxidation of the polysilicon layer 64.
In some embodiments in which the integrated circuit contains both lateral PNP devices and lateral NPN devices, a base implant procedure is performed while masking those devices which are not subjected to a base implant. When a base implant step is performed, the devices are masked with photoresist to expose at least the base region of some of the bipolar transistors and the lightly doped region of the resistor. Next, the base implant is performed and the base is annealed. In preferred embodiments the base implant uses an energy of between about 30 and 100 keV, with an implant energy of between about 30 and 50 preferred. The dose of this implant is preferably about 3×10 13 /cm 3 and 8×10 13 /cm 3 . In preferred embodiments the anneal is performed by heating the structure to 950° C. for 45 minutes, and results in a base region 21 having a thickness of between about 1,000 and 2,000 Å with a dopant concentration of between about 1×10 18 and 1×10 19 /cm 3 , with a dopant concentration of about 5×10 18 /cm 3 preferred.
Thereafter a mask (not shown) is formed which exposes regions 70a, 70b, and 70c (FIG. 2c) which will eventually be a portion of the resistor, and the collector and emitter poly contacts. The regions are preferably doped p+ to a concentration of between about 1×10 19 and 1×10 20 /cm 3 with a dopant concentration of about 6×10 19 /cm 3 preferred using boron. The p+ mask is removed and another mask 69 is formed on the surface of the device to expose regions 68a and 68b, which will eventually be used as the polysilicon covering the base region, and the bipolar base contact. The regions 68 are doped n+ using an arsenic implant with an energy of about 100 keV to a concentration of between about 5×10 19 and 1×10 20 /cm 3 .
As shown in FIG. 2d, a layer of nitride 67 having a thickness of between about 1,000 and 1,200 Å is deposited for the purpose of preventing etch undercutting of the underlying polysilicon. The polysilicon layer 64 is then annealed at 900° C. for a time of about 15 minutes.
Next, a mask (not shown) is formed on the surface of the nitride to protect the base, emitter, and collector contacts 20, 26, 26' of the bipolar transistor, the poly overlying the base 27 and the resistor 24. A dry etch with chlorine chemistry results in the structure shown in FIG. 2e. As shown, the etch is conducted such that regions of the bipolar base 21a, 21b are etched below the original epitaxial surface by about 1000 Å to 2000 Å to reduce capacitance in the bipolar transistors.
The etch mask is removed. After an oxidation step to grow a cap oxide, as illustrated in FIG. 2f, a p-type LDD using a dopant such as BF 2 is performed across the surface of the bipolar transistor base region of the bipolar transistor exposed by a mask. Heavily doped p-regions 74, 76 which are self-aligned are formed in the base contact of the bipolar transistor. The resulting net dopant concentration in the regions 74, 76 is between about 5×10 17 and 1×10 19 /cm 3 . The implant energy is preferably between about 40 and 60 keV.
Referring to FIG. 2g, nitride is stripped from the surface of the device and a Low Temperature Oxide (LTO) deposition is performed. A silicide exclusion mask, not shown, is formed on the device on polysilicon regions where silicide formation is not desired (e.g., over the center portion 78 of the resistor and the upper surface of the polysilicon overlying the base 27). The oxide is then etched back, leaving oxide 85 on the upper surface of the polysilicon overlying the base 27 and leaving spacer oxide 43, 44 on exposed sides of the emitter, collector and base contacts 20, 26, 26' and the polysilicon overlying the base 27 using means known to those of skill in the art. Another mask 77 (FIG. 2h) is then formed over the device for protection of at least the resistor oxide 78, and the sidewall oxide 44 and upper surface oxide 85 on the polysilicon overlying the base 27 as seen in FIG. 2h. The device is etched with BOE for about 1 minute and, as shown in FIG. 2h, the oxide is removed from the sidewall of the emitter, and collector poly contacts.
Referring to FIG. 2i, a mask is formed and a heavy p+ (BF 2 ) implant 82 is performed in the regions shown therein, i.e., in the collector emitter regions of the bipolar transistor 74, 76. The purpose of this implant is to further lower the resistance of those regions. The implant uses an energy of between about 40 and 60 keV.
Next, as shown in FIG. 2j, a layer of refractory metal 84 such as titanium, molybdenum, tantalum, tungsten, or the like, is deposited across the surface of the device. Using means well known to those of skill in the art, the layer is heated to about 750° C. for about 10 seconds, preferably using a rapid thermal anneal (RTA). The heating results in formation of a metal silicide in regions where the deposited metal 84 is in contact with polysilicon. Remaining unreacted metal is then etched away from the device, e.g., using H 2 O 2 or NH 3 OH, leaving a structure as shown in FIG. 2k. As shown therein, the bipolar polysilicon collector and emitter contacts 26, 26' are covered with silicide 46a, 46b, 46e, 46f across their horizontal upper surfaces, and along their vertical sidewalls. In addition, the silicide contacts extend from the vertical sidewalls along the horizontal upper surface of the single-crystal base 46c, 46d fully up to the sidewall oxide 44 of the polysilicon 27 overlying the base. The silicide 46 g, 46h on the base contact 20 extends up the vertical sidewall of the base contact and fully across the horizontal upper surface of the contact, terminating on the field oxide region 22b. The contact scheme disclosed herein provides reduced resistance through silicidation of the sidewall polysilicon contact, thereby increasing the current drive capability of the transistors and eliminating the polysilicon-silicon contact resistance. It is believed that sidewall silicidation of the local interconnects improves the resistance of the interconnect by a factor of about 2, thereby enhancing the circuit performance.
FIG. 2l illustrates the next step in the fabrication sequence in which oxide layer 56 is deposited and masked to form contact holes 86 therein. Metal is deposited on the surface of the device, masked, and etched from selected regions, providing the device shown in FIG. 1.
As can be seen from FIG. 2l, the bipolar device provided according to the disclosed invention has the silicide layer excluded from the upper surface of the N+ doped polysilicon protecting the n- base width region 21 of the device. During fabrication, and particularly during thermal cycles, an amount of arsenic diffuses across the interface between the underlying n-doped regions 16 and the polysilicon overlying the base region 27 into the n-type region 27a. It has been found that by excluding the silicide layer as disclosed, the arsenic diffusion which takes place does not travel as deep or result in as great an arsenic concentration in the region 27a as when a silicide layer is present. The resultant reduction in arsenic diffusion results in a higher BV ceo . A device produced according to the disclosed invention yields a BV ceo of 8 to 10 V. The device has a peak current gain of about 10 for a 1.5 micron base width device. This device is suitable for emitter-coupled logic (ECL) PAL applications utilizing programmable lateral fuse devices.
FIGS. 3A through 3J correspond generally to FIGS. 2c through 2l but illustrate a second embodiment of the invention. According to the second embodiment of the invention, the polysilicon region 27' residing in the base region is masked to prevent any doping so that it remains an intrinsic polysilicon region. Thus, comparing FIG. 3A to FIG. 2c, it can be seen that in this second embodiment the mask 69 is configured so that it does not expose the region of polysilicon 68a which will become the polysilicon adjacent the base 27. Thus, upon implanting with arsenic, region 68a remains as intrinsic polysilicon, while region 68b becomes n+ doped. Region 68a remains as intrinsic polysilicon throughout the remaining steps including formation of a layer of nitride 67 (FIG. 3B), masking and etching the polysilicon (FIG. 3E), p- type LDD (FIG. 3D), formation of sidewall oxides (FIG. 3E), etching to strip undesired sidewall oxide (FIG. 3F), heavy p+ implant 82 (FIG. 3G), deposition of refractory metal 84 (FIG. 3H), heating to form metal silicide (FIG. 3I), and deposition of an oxide layer 56 (FIG. 3J).
By maintaining the polysilicon region 27' in an intrinsic state, substantially no arsenic diffuses across the interface between the polysilicon region 27' and the adjacent doped epitaxial region 21, and thus there is no structure corresponding to region 27a of FIG. 1a. As a result, breakdown occurs as a floor breakdown rather than corner breakdown phenomenon. When both the n+ implant and silicide are removed from the polysilicon overlying the active base region of the device 27, the device typically yields a BV ceo of about 20 V which is equivalent to a standard vertical NPN BV cbo value. This is accomplished through a subsequent reduction in current gain on a device having a wider 2.0 micron base width, due to more recombination of holes along the intrinsic polysilicon-single crystal silicon interface. The peak current gain of this device is close to unity which is suitable for transistor-transistor logic (TTL) PAL circuits utilizing programmable vertical fuse devices.
III. Device Performance
Bipolar devices were constructed according to the disclosed invention and subjected to voltages ranging from -20 volts to +20 volts while a resultant current was measured. The devices tested had a base width of about 1.5 to 2 microns. FIG. 4a depicts the measured currents in a device formed according to previous methods, in which the polysilicon overlying the base is silicided and n+ type. FIG. 4b depicts the measured currents in a device formed without silicide on the polysilicon adjacent the base region, but with the polysilicon being n doped, as depicted in FIG. 1a. FIG. 4c depicts the measured current in a device which has no silicide on the polysilicon overlying the base region and also in which the polysilicon overlying the base region is intrinsic, corresponding to FIG. 1b. FIG. 5 is a plot of current gain (designated HFE) as a function of collector current for a device in which the polysilicon adjacent the base region is doped and unsilicided (as in FIG. 1a). The current gain depicted in FIG. 5, in general, is similar to current gain obtained from previously available devices in which the polysilicon overlying the base region is silicided. FIG. 6 is a plot generally corresponding to FIG. 5, for a device having neither silicide nor doping in the polysilicon overlying the base region (as depicted in FIG. 1b).
In general terms, although previous devices have provided a BV ceo of about 6 volts, the corresponding value when there is no silicide on the polysilicon overlying the base region is about 7 to 10 volts, and when the polysilicon overlying the base region is intrinsic, about 20 volts. Current gain in previous devices is about 10 and remains about 10 in devices from which silicide is excluded in the polysilicon overlying the base region. The current gain when the polysilicon overlying the base region is intrinsic is about 1. These results are summarized in Table 1.
TABLE 1______________________________________Polysilicon Overlying Base Region CurrentSilicided? Doped or Intrinsic BV.sub.ceo Gain______________________________________Yes Doped 6 V 10No Doped 7-10 V 10No Intrinsic 20 V 1______________________________________
It is to be understood that the above description is intended to be illustrative and not restrictive. Many variations of the invention will become apparent to those of skill in the art upon review of this disclosure. Merely by way of example particular regions of the devices shown herein have been illustrated as being p-type or n-type, but it will be apparent to those of skill in the art that the role of n- and p-type dopants may readily be reversed. Further, while the invention has been illustrated with regard to specific dopant concentrations in some instances, it should also be clear that a wide range of dopant concentrations may be used for many features of the devices herein without departing from the scope of the inventions herein. Still further, while the inventions herein have been illustrated primarily in relation to a bipolar device, many facets of the invention could be applied when the bipolar devices are fabricated on a common substrate with PMOS, NMOS, and/or CMOS devices. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims along with their full scope of equivalents. | A bipolar lateral device is disclosed having a high BV ceo . The device is formed according to a single polysilicon process. In one embodiment silicide is excluded from the surface of the N+ doped polysilicon protecting the N- base width region of the device and the resulting device has a BV ceo of 8 to 10 V. In another embodiment, the silicide is excluded from the surface of the polysilicon protecting the n-base width region and the polysilicon is maintained as intrinsic polysilicon. The resulting device has a BV ceo of about 20 V. The devices are useful as voltage clamping devices in programmable logic circuits which must withstand a collector to emitter reverse bias voltage that is sufficient to program either vertical fuse or lateral fuse devices. | 8 |
BACKGROUND OF THE INVENTION
1. Cross-Reference to Related Applications
This application is a continuation of application Ser. No. 927,946, filed Nov. 07, 1986, now U.S. Pat. No. 4,732,559, which is a continuation-in-part of U.S. application Ser. No. 828,187, filed Feb. 11, 1986, abandoned. The disclosure of the foregoing patent is incorporated into this application in its entirety by reference thereto.
2. Field of the Invention
This invention relates to a fuel combuster, more particularly to a torch tip, and specifically to a hand held torch tip.
3. The Prior Art
Numerous attempts have been made to provide a torch tip which produces an even flame, which is easy to light, which will operate under any pressure, and which will not overheat.
U.S. Pat. No. 4,013,395 to Wormser discloses a fuel combuster which uses a vortex generator as a flame holder which results in a swirling flame. In this type of device, a relatively slight drop in gas pressure will cause the tube of the torch tip to overheat, because the velocity of the gas is not adequate to keep burning gas from contacting the tube. Further, increasing gas pressure in a high pressure torch tip, such as disclosed in the '395 patent, will narrow the flame to the point where it collapses and assumes an hourglass-like shape. A flame in such a shape has no utility for soldering or brazing because it loses heat concentration; the flame collapses, and will not effectively solder.
U.S. Pat. No. 1,510,060 to Hoover et el. discloses a gas burner with a mixing tube. A wire screen is supported adjacent to the end of a mixing tube bymeans of a cross bar. The wire screen is disclosed as serving to assist the breaking up of the air and gases are passed out of the tube, and ignition of the mixture is further disclosed to take place upon the wire screen.
U.S. Pat. No. 1,945,902 to Johnson discloses a burner having a combustion chamber formed with a circular aperture through which a burner tube is inserted. The aperture is provided with notches which edge the ignition area of the upper ignition into the burner tube. These apertures provide air inlet openings to the combustion chamber. A plurality of perforated baffle plates are located on the upper end of the burner tube, and are laid flat on top of each other in a closely adjacent relationship. These baffle plates comprise circular discs of twelve mesh fine iron wire cloth or other similar material, to preheat the premixed air and gas. The air and gas passes to an uppermost screen and is ignited therein.
U.S. Pat. No. 3,752,644 to Arnal discloses a hot air generator using a gaseous fuel. The mixture of primary air and gaseous fuel is drawn into the interior of the mixing tube by the centrifugal fan formed by a number of radial fins. This mixture is discharged into the interior of the combustion chamber, and is ignited by a pilot flame such that the flame is initiated on contact with a grid. The products of combustion are mixed with air pulsated by the fan, following which the mixture of hot air thus obtained is carried into the space to be heated.
U.S. Pat. No. 396,260 to Bell discloses an incandescent gas burner having a burner tube, which supports a wire-gauze diaphragm and a burner-tip. A deflector receives and protects the skirt of the mantle.
U.S. Pat. No. 629,296 to Johnson discloses a gas burner wherein gas travels through a number of conduits and through a seat. A ring of wire-gauze is arranged within the seat. The gas issues from a number of perforations and is ignited to form an annular belt of flame.
U.S. Pat. No. 1,015,851 to Storrs discloses a burner for incandescent mantles. The burner comprises a bunsen tube, a burner tip, a mantle and gauze. The gauze is of a curved shape and is provided with an upturned rim. The upturned rim and lower edge of the gauze lie within an annular chamber, the lower edge resting on the top of the tip and the upper edge resting in engagement with the annular shoulder. The gauze is disclosed as preventing back firing without impeding the passage of the gas/air mixture to the burner.
U.S. Pat. No. 1,058,702 to Tait discloses a testburner which includes a wire gauze disc held in position by an upper section and a lower section. The chamber of the lower section and the chamber of the upper section form a fuel expansion chamber across which gauze extends so that the gas from the pipe expands in the expansion chamber and passes through the gauze. Gas passes through the chamber of the upper section to the upper end of the chamber to the lower section and out of an opening. The gas burns in a full, regular jet which projects from the opening, and extends back into the chamber of the lower section to a greater or lesser extent determined by the volume and pressure of the gas. The gauze is disclosed as a flame barrier which prevents back lashing, and a barrier for solid particles in the gas.
U.S. Pat. No. 2,531,015 to Thompson discloses an internal ring brazing burner having a number of gas jets staggered around an annular flange in such a manner that if a sheet of flame is directed toward the center of the burner but tangent to a circle inside the periphery of the burner. A screen is inserted into an inner shell to prevent backfiring during operation of the burner. The screen is not near the flame and has no unction which pertains to flame holding.
U.S. Pat. No. 2,564,371 to Parsberg discloses a burner for giving flashing light. The burner includes a flange, in which a conical base for a grill mantle rests. A screen is situated below a flame deflector, and there is no indication that this screen can serve any function pertaining to flame holding.
The Wormser patent operates on swirl principles. The conventional swirl-type torch tips include a number of disadvantages. One of these disadvantages is that these types of torch tips easily overheat, due to even relatively slight drops in gas pressure. Another disadvantage is that an increase in the gas pressure will narrow the flame to the point where it collapses and assumes an hourglass-like shape.
the prior art linear principle devices have the disadvantage that they are typically extremely hard to light.
Standard high velocity torch tips, (e.g. those intended to operate with a high gas pressure) are subject to a further disadvantage. When the device is operated below a certain pressure or velocity, the standard tubes overheat. They turn red hot because the velocity is not adequate to keep the burning gas from contacting the tube.
None of the prior art devices provides a torch tip which is easy to light, will not overheat, and will operate over a wide pressure range.
OBJECTS OF THE INVENTION
It is therefore an object to the invention to provide a combustion device, more specifically a torch tip, which will burn over a much wider pressure range without overheating.
A still further object of the invention is to provide a baffle device which allows the gas, to stall temporarily, making it easier to light the flame.
It is still a further object of the invention to provide a baffle which will work with both high velocity and low velocity gases.
It is still a further object of the present invention to provide a torch tip which can sustain a substantial drop in the pressure range without overheating the tube.
SUMMARY OF THE INVENTION
The objects of the invention are achieved by providing a combustion device for generating a linear flame which includes means for combining a fuel gas and a combustion supporting gas, and means for stalling the combined fuel gas and combustion supporting gas when the combined gases are moving either at a low velocity or a high velocity.
In one embodiment, the combustion device of this invention comprises a metallic elongated tube, [e.g., a torch tip,] having a forward section terminating in a front end, a middle section and a rearward section, the middle section communicating at its respective ends with the forward section and the rearward section respectively. The rearward section is adapted, suitably at its rearward end, for connection to a source of combustible gas, and is suitably provided with axially positioned fuel jet means for injecting combustible gas into the tube and with apertures, suitably four or more in number, for intake of combustion supporting gas to be mixed with the combustible gas. The portion of the rearward section forward of the fuel jet means is provided with an axial passageway for transporting the combustible gas and the combustion supporting gas to the middle section. This passageway is of smaller diameter than the internal diameter of the forward section and the connecting middle section is at least in part of frustoconical shape, adapted to provide a Venturi effect.
The means for stalling the gases comprises a baffle positioned in the forward section. The baffle comprises a substantially circular inner portion, a generally annular portion surrounding the inner portion and a plurality of radially extending ribs which connect the baffle to the inside wall of the forward section.
The inner portion may be made of a wire mesh of heat resistant material, preferably of stainless steel, and operates to baffle low velocity combined gases. The wire mesh may define a substantially flat or curved surface. Preferably, it defines a curved surface, the central portion of the curve being the portion of the wire mesh closest to the front end of the forward section.
Preferably, the inner portion is gas permeable. The term "gas permeable", as used herein, refers to a structure which greatly slows, or even virtually stalls, a gas flowing against it, and reverses the flow of the majority of such gas. The gas passes through, greatly slowed, by wending its way between the particles comprising the "gas permeable" structure.
A "gas permeable" inner portion may be a wire mesh made of strands so closey spaced that light is not visible through the mesh. Mesh of plain Dutch weave is gas permeable within the meaning of the term as used herein.
The gas permeable inner portion may be a material comprising a randomly organized solidified matrix of particles. Preferably, this material is a sintered powdered metal, such as stainless steel. The material may instead be a ceramic material, such as alumina.
The term "gas permeable", as used herein, does not refer to structures which allow clear, unimpeded passage of gas. A tunnel, or even a screen through which light is visible, in the manner of a screen door, is not "gas permeable" as the term is used herein.
The generally annular portion and ribs are solid, and gas impermeable. The generally annular portion may be truly annular, polygonal, or of other modified annular shape;for instance, it may have a circular inner edge and a pentagonal outer edge, as shown in FIG. 7. It cooperates with the wire mesh to baffle high velocity combined gases. The plurality of ribs extend between the outer edge of the annular portion and the inside wall of the tube. The annular portion and the ribs are also made of heat resistant material, preferably stainless steel. High density sintered powdered metal is also suitable for the generally annular portion and ribs.
The entire baffle may be a single element of variable density sintered powdered metal or variable density ceramic material. In such a construction, the ribs and generally annular portion are of sufficient density so as to be gas impermeable, and the inner portion is of a density sufficiently low so as to be "gas permeable" within the meaning of the term as defined herein.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred embodiments of the invention will be discussed with reference to the drawings as follows:
FIG. 1 is a side view of an embodiment of the torch tip of the present invention;
FIG. 2 is an end view of the torch tip of that embodiment;
FIG. 3 is an enlarged front view of the baffle shown in FIGS. 1 and 2;
FIG. 4 is a cross-sectional view of the baffle, employing a curved wire mesh, taken along plane 4 of FIG. 3;
FIG. 5 is a side view of another embodiment of the torch tip of the present invention;
FIG. 6 is an end view of the torch tip of that embodiment;
FIG. 7 is an enlarged front view of the baffle shown in FIGS. 5 and 6;
FIG. 8 is a cross-sectional view of the baffle, employing a substantially flat wire mesh, taken along plane 8 of FIG. 7.
FIG. 9 is a cross-sectional view of the baffle, comprising a single element of variable density powdered sintered metal.
FIG. 10 is a cross-sectional view of the baffle, comprising a single element of variable density ceramic material.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 is a side view of the torch tip 1 of the present invention. Torch tip 1 has a substantially tubular shape, and can be viewed as an elongated tube having three distinct sections A, B, C.
Section A is the rearward section of torch tip 1 which is adapted at its rearward end to be connected to a source of fuel as by internally threaded means 2 or other means, such as quick connects. Section A includes a middle portion 3 of substantially rectangular cross-section which has openings 4 through which air is introduced into torch tip 1. Openings 4 are shown here as four in number and as having a generally circular shape, but this is for illustrative purposes only, and it is understood that other shapes and/or numbers of openings 4 would be within the scope of the invention. An axially disposed jet nozzle 5 is included within the middle portion 3 of section A. The fuel gas passes from the source of fuel into and through jet nozzle 5. The fuel gas ejected by jet nozzle 5 mixes with air which is introduced into tube. 1 by openings 4. An axial passageway 6 is provided in the forward portion of the rearward section A for the passage of fuel gas and air into section B of the torch tip 1.
Connecting means 2, middle portion 3 and jet nozzle 5 are preferably made of brass. Axial passageway 6 is suitably provided by a stainless steel tube 7 which extends into and is joined to middle portion 3.
Section B is the middle section of torch tip 1 and is of a generally frustoconical shape. It is preferably made of stainless steel. This section provides a Venturi effect causing a large quantity of air to be sucked in by the cold fuel gas ejected by jet nozzle 5 and expanded and mixed with the fuel gas prior to burning. This creates a highly efficient flame with good characteristics.
Section C is the forward section of torch tip 1. It has a generally cylindrical shape, and is preferably made of stainless steel. The internal diameter of Section C is larger than the diameter of passageway 6. Its outlet 8 constitutes the flame end of the torch tip. As shown in the cutaway portion of section C, a baffle 9 is positioned within this section.
FIGS. 2, 3 and 4 further illustrate baffle 9 of the present invention.
Baffle 9 includes a substantially circular wire screen 10. Wire screen 10 preferably defines a curved surface, situated in Section C so that the central portion of the curve is the portion of the screen closest to flame end 8 of tube 1. Wire screen 10 is further preferably made out of stainless steel woven in a plain Dutch weave pattern.
Surrounding wire screen 10 is a solid metallic annular ring 11, also preferably of stainless steel. Wire screen 10 is fastened in a groove in annular ring 11, or is made integral with annular ring 11 by any other suitable means.
Extending from annular ring 11 are a plurality of outwardly and radially extending symmetrically positioned ribs 12, preferably of stainless steel. Ribs 12 serve to connect the annular ring with the inside of wall 13 of torch tip 1. Ribs 12 are constrained inside torch wall 13 by friction and/or crimps 14 in the torch tip wall, or by other suitable permanent attachment method. Spaces 15 are provided at the outside edge of annular ring 11, between ribs 12.
The phenomena occurring in the operation of the invention are not fully understood. To the extent which these have been detected and analyzed, they are discussed below.
Baffle 9 serves to stall the fuel and air mixture, further enhancing combustion. In operation, the temperatures of the object heated with air/MAPP mixture is approximately 2,100° F. and for an air/propane mixture, approximately 1750° F. (MAAP is a trademark of AIRCO, Inc. for methyl acetylene-propadiene). The torch tip of the present invention burns with a blue flame which indicates a more complete combustion. This is,in distinction to the swirl type device of the '395 patent which has a large green area indicating unburned fuel. The fuel tip of the present invention can operate at a pressure behind the jet nozzle 5 orifice in the range of 12 psi to 50 psi on MAPP. The device of the '395 patent is limited to pressures of between 25psi and 40psi on MAPP.
In operation, the solid portion of baffle 9, i.e. ring 11 and ribs 12, is the high velocity area; when the gas is at high velocity, the primary flame holding occurs on the forward surface of the solid portion. Wire screen 10 is a low velocity area; when gas is at a low velocity, the primary flame holding occurs on the wire screen. Burning takes place from immediately in front of the baffle and extends outside of the tip, but does not touch the inside of wall 13 of the tip. Therefore the tip does not get hot even when the gas is at a low velocity.
The particular design of baffle 9 in the present invention provides a number of advantages.
A wire screen alone, with no solid exterior portion would only work at a low velocity air/fuel mixture to baffle the gas and slow it down enough for the gas to burn. A totally wire baffle creates problems with thermal stability. As the temperature changes, the screen becomes wavy and changes shape. Additionally, such a screen would not remain in place within the tube.
A solid device likewise would not be adequate because the solid baffle would hold the gas back, which would make igniting the torch more difficult. The solid baffle would also produce the eddies in the gases, which create the mixing necessary for combustion, only over a limited velocity range. Moreover, the torch tip employing a solid baffle would be ignitable at only one specific pressure point.
Likewise a solid disc with little holes is not sufficient.
The spaces 15 let the gas and air mixture through the baffle at a higher velocity. When the gas is ignited, there is slow moving gas coming through the wire screen and faster moving gas through the spaces 15 on the outside of annular ring 11. The gas inside the screen will ignite first, providing enough heat for the gas on the outside of the annular ring to be ignited.
The elements of the torch tip are configured and arranged so that the flow of gases passing through spaces 15 provides a Venturi effect, causing a pressure reduction on the face of wire screen 10 which extracts gas molecules through the screen. Combustion is accordingly caused to occur above wire screen 10.
Wire screen 10 reverses the majority of the gas which contacts the screen; this effect is enhanced where the screen defines a curved surface with the central portion of the curve being that portion of the screen closest to flame end 8 of tube 1. As a result, dwell time of the gases in the torch tip is increased, and mixing of the gases is enhanced.
The type of wire mesh suitable for screen 10 is that which provides sufficient resistance to greatly slow or stall passage of the gases through the screen, but allows enough gas to be extracted through for ignition. One wire screen which meets these requirements is plain Dutch weave of 50 warp ×250 shute, with 0.0055" warp and 0.0045" shute, and 60 nominal micron retention.
The device of the present invention creates a flame which will stay linear and substantially unnarrowed in the operable pressure range. The higher velocity of the gas and air mixture moving through space 15 imparts, as it flows past the article to which the flame is applied, a "wrapping" effect to the cone -- that is, the flame tends to wrap around the article to which it is applied. This wrapping effect provides for a more even distribution of heat than is achieved where the flame must be applied to one side of the article at a time. The device of the Wormser patent also provides for a wrapping effect, but not to the same extent as the device of the present invention.
FIGS. 5-8 illustrate a torch tip embodiment 21 generally similar to that shown in FIGS. 1-4. The forward section C' is substantially the same as forward portion C in FIG. 1. The middle section B' differs from middle section B in FIG. 1 by having a generally arcuate shape. Middle section B' includes a generally frustoconical portion 35, the larger diameter end of which is joined to the rearward portion of Section C . Rearward section A' is adapted to be connected to a source of combustible gas, as by externally threaded end portion 22, a quick connect or other means. Section A' includes a middle portion 23 which, as shown, has four openings 24, suitably circular or generally circular, for the intake of air and an axially disposed jet nozzle 25. However, other shapes and numbers of openings may be employed. An axial passageway 26 is provided in the forward portion of the rearward section A'. Axial passageway 26 is suitably provided by a tube 27 which extends into and is joined to middle portion 23.
FIGS. 6, 7, and 8 illustrate baffle 29. Baffle 29 includes a substantially circular wire screen 30. Surrounding wire screen 30 is a solid metallic modified annular portion 31, the annular shape being modified in the sense that the outer portion is generally in the shape of a regular polygon with symmetrically spaced outwardly projecting radial ribs 32. Ribs 32 serve to connect the modified annular portion 31 with the inside of wall 33 of torch tip 21, suitably with the aid of crimps 34 in the torch tip wall.
Except for the differences as illustrated in the figures and discussed above, the construction and operation of the embodiment of FIGS. 5-8 is otherwise similar to those of FIGS. 1-4 and provides the same advantage.
Fig. 9 illustrates baffle 36, comprising a single element of variable density sintered powdered stainless steel. Baffle 36 includes gas permeable inner portion 37. The term "gas permeable", as discussed earlier herein, refers to ther property of greatly slowing, or even virtually stalling, a gas flowing against it, and reversing the flow of the majority of such gas; gas passes through, greatly slowed, by winding its way between the particles comprising inner portion 37. Substantially annular gas impermeable portion 38 surrounds inner portion 37. Gas impermeable ribs 39 of baffle 36 serve to connect baffle 36 with the inside wall of the torch tip.
Fig. 10 illustrates baffle 40, comprising a single element of variable density alumina. Corresponding to baffle 36, baffle 40 is provided with gas permeable inner portion 41, gas impermeable ribs 43.
As with baffle 9 and 29, baffles 36 and 40 are constrained inside the torch wall by friction and/or crimps, or by any other suitable permanent attachment method.
Like the phenomena occurring in the operation of the invention, also not fully understood is the relative importance of the different elements, or the relationship of their dimensions necessary for operability. However, dimensions for particular embodiments which are operative are listed in the Table.
TABLE______________________________________Model Number LPT4 LPT5 LPT6______________________________________Distance along central 0.528"- 0.640"- 0.640"-axis of baffle and 0.750" 1.575" 1.87torch tip tube betweenfront end of baffleand flame end of torchtip tubeLength of baffle along 0.187" 0.205" 0.205"central axis of baffleand torch tip tubeDistance along central 0.020" 0.020" 0.020"axis of baffle andtorch tip tube betweenfront end of baffleand central portion offront side of wirescreenDistance along central .040" .040" .040"axis of baffle andtorch tip tube betweenfront end of baffleand central portion ofrear side of wirescreenDiameter of wire screen 0.300" 0.440" 0.540"No. of ribs on baffle 3 5 5Degrees of radius 120° 72° 72°between centers ofimmediately adjacentribsGeometrical configura- annular circular circulartion of annular ring inner edge, inneror modified annular ring pentagonal edge, outer edge penagonal outer edgeDiameter of baffle to 0.250" 0.390" 0.500"inner edge of annularring or modified an-nular ringDiameter of baffle to 0.325" -- --outer edge of annularring or modified annu-lar ringDiameter of baffle to 0.437" 0.688" 0.875"end of ribDiameter of torch tip 0.437" 0.688" 0.875"tube at flame endLength of rib between 0.100" 0.100" 0.100"edges of rib whichintersect annularring or modifiedannular ringHeight of rib from 0.056" 0.075" 0.100"outer edge of annularring or modifiedannular ring to edgeof rib farthest fromannular ring or modi-fied annular ringDistance between 0.397" 0.235" 0.312"nearest edges ofadjacent ribs atpoints where the ribsintersect the outeredge of the annularring or modifiedannular ring______________________________________
although the invention has been specifically described with reference to particular means and embodiments, it is to be understood that the invention is not limited to the particulars disclosed but extends to all equivalents within the scope of the claims. | A combustion device which includes a forward section in which a baffle has been inserted for stalling the air and fuel mixture as it passes through the torch tip, generating a linear flame. The baffle is designed to include a substantially circular inner portion of wire screen, sintered powdered metal, or ceramic material, surrounded by a solid annular or substantially annular ring. A plurality of ribs extend between the annular ring and the inside of the tube for connecting the annular ring to the tube and for defining a number of outer passages through which air/fuel mixture may pass. | 5 |
This is a continuation of application Ser. No. 08/620,286 filed on Mar. 22, 1996. Now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the closure of intravascular defects and more specifically to a device for closing a septal defect, the device being delivered to the site of the defect by a catheter and comprising a metallic or polymeric material which is adjusted by mechanical means to a configuration which functions as a plug.
2. General Background
The heart is divided into four chambers, the two upper being the left and right atria and the two lower being the left and right ventricles. The atria are separated from each other by a muscular wall, the interatrial septum, and the ventricles by the interventricular septum.
Either congenitally or by acquisition, abnormal openings, holes or shunts can occur between the chambers of the heart or the great vessels (interatrial and interventricular septal defects or patent ductus arteriosus and aorthico-pulmonary window respectively), causing shunting of blood through the opening. The ductus arteriosus is the prenatal canal between the pulmonary artery and the aortic arch which normally closes soon after birth. The deformity is usually congenital, resulting from a failure of completion of the formation of the septum, or wall, between the two sides during fetal life when the heart forms from a folded tube into a four-chambered, two unit system.
These deformities can carry significant sequelae. For example, with an atrial septal defect, blood is shunted from the left atrium of the heart to the right, producing an over-load of the right heart. In addition to left-to-right shunts such as occur in patent ductus arteriosus from the aorta to the pulmonary artery, the left side of the heart has to work harder because some of the blood which it pumps will recirculate through the lungs instead of going out to the rest of the body. The ill effects of these lesions usually cause added strain on the heart with ultimate failure if not corrected.
Previous extracardiac (outside the heart) or intracardiac septal defects have required relatively extensive surgical techniques for correction. To date the most common method of closing intracardiac shunts, such as atrial-septal defects and ventricular-septal defects, entails the relatively drastic technique of open-heart surgery, requiring opening the chest or sternum and diverting the blood from the heart with the use of a cardiopulmonary bypass. The heart is then opened, the defect is sewn shut by direct suturing with or without a patch of synthetic material (usually of Dacron, teflon, silk, nylon or pericardium), and then the heart is closed. The patient is then taken off the cardiopulmonary bypass machine, and then the chest is closed.
In place of direct suturing, closures of interauricular septal defects by means of a mechanical prosthesis have been disclosed.
U.S. Pat. No. 3,874,388 to King et al. relates to a shunt defect closure system including a pair of opposed umbrella-like elements locked together in a face to face relationship and delivered by means of a catheter, whereby a defect is closed. U.S. Pat. No. 5,350,399 to Erlebacher et al. relates to a percutaneous arterial puncture seal device also including a pair of opposed umbrella-like elements and an insertion tool.
U.S. Pat. No. 4,710,192 to Liotta et al. relates to a vaulted diaphragm for occlusion in a descending thoracic aorta.
U.S. Pat. No. 5,108,420 to Marks relates to an aperture occlusion device consisting of a wire having an elongated configuration for delivery to the aperture, and a preprogrammed configuration including occlusion forming wire segments on each side of the aperture.
U.S. Pat. No. 4,007,743 to Blake relates to an opening mechanism for umbrella-like intravascular shunt defect closure device having foldable flat ring sections which extend between pivotable struts when the device is expanded and fold between the struts when the device is collapsed.
U.S. Pat. No. 4,699,611 to Bowden relates to a biliary stent having radially protruding lobes.
There still exists a need, however, for a simple mechanical method of closing septal defects, either temporarily or permanently, with an improved plug having a unitary construction that is adjusted by mechanical means from a delivery configuration to a configuration which functions as a plug at the site of a defect.
SUMMARY OF THE INVENTION
The present invention provides devices and method for closing off, restricting the blood flow through or plugging a septal defect, the devices being made of metallic or polymeric materials in specific conformations which are delivered to the area of defect by a catheter means and adjusted by mechanical means to a configuration which functions as a plug or restriction.
The device may contact both sides of the septum thereby plugging the septal defect.
The septal defect closure device of the present invention may be used to close the ductus arteriosus, ventricular septum or atrial septum, or may even be used to block or fill an artery, vein or other vessel.
The device may be in any shape which is suitable for filling and plugging a defect. The defect may be contacted by the surface of the metallic material or polymeric material, which is biocompatible.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows an anterior to posterior sectional view of a human heart, showing a typical atrial septal defect (ASD) prior to closure, and a typical ventricular septal defect (VSD) prior to closure by the device of the present invention;
FIG. 2 shows a side view of a septal defect closure device of the present invention in its delivery state;
FIG. 3 is a side view of the device of FIG. 2 in an intermediate conformation which it would assume after delivery and during its mechanical transformation into a plug;
FIG. 4 is a side view of the device as in FIG. 3 after its mechanical transformation into a plug;
FIGS.5a and 5b are anterior to posterior sectional views showing the delivery and placement of the septal defect closure device of FIG. 2;
FIG. 6 is a sectional view of an alternative embodiment of a device according to the present invention;
FIG. 7 is a sectional view thereof taken along line 7--7 in FIG. 6;
FIG. 8 is a sectional view thereof taken along line 8--8 in FIG. 6;
FIG. 9 is a view similar to that of FIG. 6 showing an alternative view thereof;
FIG. 10 is a sectional view thereof taken along line 10--10 in FIG. 9;
FIG. 11 is a perspective view of an intralumen mechanical mechanism thereof;
FIG. 12 is a perspective view thereof;
FIG. 13 is a perspective view of an alternative embodiment of the intralumen mechanical mechanism thereof;
FIGS. 14-15 respectively show a perspective view of an alternative embodiment of a device according to the present invention and a pull mechanism whereby the device is transformed into a plug;
FIGS. 16-17 show a sectional view of the device of FIG. 14 including a pin locking mechanism;
FIG. 18 is a perspective view of the invention with deployment catheter;
FIG. 19 is a perspective view of an alternative embodiment thereof; and
FIG. 20 is a perspective view of an alternative embodiment thereof.
FIGS. 21-22 show a sectional view of the device as in FIGS. 14, 16 and 17 further including a plurality of tissue hooks;
FIGS. 23-24 show side views of a device as shown in FIGS. 3-4 respectively, the device further including a plurality of tissue hooks, FIG. 23 showing an intermediate conformation which the device would assume after delivery and during its mechanical transformation into a plug, FIG. 24 showing a side view of the device as in FIG. 23 after its mechanical transformation into a plug;
FIG. 25 is an anterior to posterior sectional view showing the septal defect closure device of FIGS. 23-24 after delivery to the atrial and ventricular defects as depicted therein.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides an apparatus and method of closing off restricting the blood flow therethrough or plugging a septal defect. The apparatus comprises a catheter delivered device to close a septal defect, the device comprising a hollow shaft with cuts or grooves in the wall of the device which create deformable hinged support struts. The shaft may have a circular cross section. The device may suitably be made of any biocompatible material. Alternatively the device could be made of a non-biocompatible material with a suitable biocompatible coating.
The device of the present invention may be made of any suitable polymeric material including but not limited to polycarbonate urethanes, polyamides, polyether urethanes, polyethylene terephthalate (PET), polybutylene terephthalate, polyethylenes, high density polyethylene, polyimides, epoxides, composites of collagen and PET, composites of high strength carbon fiber and PET and composites of PET or carbon fibers within epoxides. Any thermosets, thermoplastics, thermoplastic elastomers, elastomers, composites, pseudo-thermoplastics, carbohydrates, proteins, or mixtures thereof may suitably be used. In addition to synthetic polymers portions of the device could be constructed of natural materials as collagen I or III, or IV or of glycosaminoglycans as chondroitin sulfate or composites thereof.
The device may alternatively be made of a metallic material. Examples of suitable metallic materials include stainless steel, spring steel, memory shape metals (such as nitinol), titanium, and metal alloys of any kind not limited to the aforementioned. Furthermore, the configuration of the metal device may be solid, braided or woven.
The device may alternatively be made of carbon fiber composites coated with any of the prior cited polymeric materials or of metal fibers coated with polymeric materials. The device may be completely or partially coated with polymeric materials. The apparatus may also be comprised of metal substrates coated with polymer which is in turn coated with natural materials.
Referring now to the Figures, FIG. 1 is a sectional view of a human heart showing defects in septal tissue, a typical atrial septal defect (ASD) 6 and a typical ventricular septal defect (VSD) 6', prior to closure. The defects are shown together for illustrative purposes only, not as a depiction of multiple septal defects. However, multiple defects may be present. Apparent in the figure are left ventricle 50, left atrium 56, right ventricle 58, right atrium 60, mitral valve 54, tricuspid valve 66, inferior vena cava 62 and superior vena cava 64.
As shown in FIG. 2, the catheter delivered device, shown generally at 10, comprises a cylindrical shaft 12 having a proximal end 14, a distal end 16, and a central portion 18. Cylindrical shaft 12 has parallel cuts 20 therethrough, which as shown in FIGS. 3-5, create support struts 22. The cuts could also be helical or serpentine. The struts could be covered by a cloth or other covering.
As shown in FIGS. 2-4, 5a and 5b, hinge point 24 of support struts 22 move radially away from the axis of the device in a hinge like fashion in response to the movement of proximal and distal ends 14, 16 toward the central portion 18 of the device 10. The hinge point 24 could be formed in a variety of ways. It could be a mechanical hinge, a thinned section created by chemical etching, mechanical denting, grinding, heat forming or machining, a weakened section created by micro cuts, tapered grooves (20), chemical treatment, or any other process which will cause a preferential stress point.
As shown in FIGS. 4, 5a and 5b, the device will assume a plug like formation when in place, whereby device 10 will span both sides of the septal defect. Device 10 will be anchored to the tissue of the septal defect by the physical interaction such as pressure from struts 22. The septal defect closure device may further comprise a plurality of tissue hooks located thereon to anchor the device in place in the septal defect.
The delivery and placement of device 10 in a septal defect is illustrated in FIGS. 5a and 5b, which depict placement of the device and removal of delivery catheter 40. Like FIG. 1, FIGS. 5a and 5b depict defects 6,6' of both atrial septal tissue and ventricular septal tissue, respectively.
The route by which the cardiac defects are accessed via catheter are described as follows. An ASD or VSD may be accessed from the arterial circuit, as shown in FIG. 5a. The catheter/device is introduced into the arterial vascular system and guided up the descending thoracic and/or abdominal aorta. The device may then be advanced into the left ventricle (LV) 50 through the aortic outflow tract. Once in LV 50, the device may be deployed in VSD 6'. Alternatively, once in LV 50, the device may be directed up through mitral valve 54 and into the left atrium (LA) 56. When the device is in LA 56, it may be directed into ASD 6 and installed. In FIG. 5b, device 10 is shown already in place in ASD 6 with catheter/delivery means 40 in the process of being withdrawn. Device 10' is shown being placed in VSD 6'. Device 10' is delivered to the area of septal defect 6' by catheter 40 and inserted in place, centered in septal defect 6' as shown in FIG. 5a. Device 10' may be either pulled or pushed out of catheter 40' and installed in a manner set forth more fully hereinbelow. After installation, device 10' will assume its preformed shape in a narrow center portion with enlarged ends. Device 10 is shown in place closing off atrial septal defect 6, as catheter delivery means 40 is being withdrawn.
Alternatively, an ASD or VSD may be accessed from the venous circuit, as shown in FIG. 5b. The catheter/device may be introduced into the venous system, advanced into Inferior Vena Cava (IVC) 62 or Superior Vera Cava (SVC) 64 and guided into the right atrium (RA) 60. The device may then be directed into ASD 6.
Alternatively, once in RA 60, device 10 may be advanced through tricuspid valve 66 into the right ventricle (RV) 58 and directed into VSD 6' and installed. In FIG. 5b, device 10 is shown being placed in ASD 6. Device 10' is shown already in place in VSD 6' with catheter 40' in the process of being withdrawn. Device 10 is delivered to the area of septal defect 6 by catheter 40 and inserted in place, centered in septal defect 6 as shown in FIG. 5b. Device 10 is shown in place closing off ventricular septal defect 6', as catheter delivery means 40' is being withdrawn.
An alternative embodiment is shown in FIGS. 6-10. FIG. 6 is a cross-section of the device, indicated generally at 100. Device 100 has an interior portion 110, an exterior portion 112, proximal and distal ends 114,116 and a center portion 118. Distal end 116 of device 100 is closed to block blood flow through its interior 110. Proximal end 114 has an opening 120 which provides access to interior 110. Arrow head 122 extends proximally from distal end 116 into interior 110. Lock 124 extends distally from opening 120 at proximal end 114 into interior 110, and is shaped to mate with arrow head 122. Arrow head 122 fits or snaps into lock 124 when distal end 116 is pulled toward proximal end 114. Lock 124 has a proximal undercut 126 shaped to mate with central barbs 128, which are located in the central portion 118 of interior 110. Proximal undercut 126 snaps onto central barbs 128 when proximal end 114 is pulled towards center 118.
Device 100 may be reversibly locked in place by means of an intralumen mechanical mechanism or twist-lok mechanism 140 (best seen at FIGS. 11 and 13). Both distal end 116 and proximal end 114 have twist-lok tracks, proximal 130 and distal 132. Cross sections of proximal twist-lok track 130 and distal twist-lok track 132 are shown at FIGS. 7 and 8, respectively. Proximal twist-lok track 130 is shown at FIG. 7 with twist-Lok mechanism 140 at resting/delivery position. Twist-lok mechanism 140 comprises a hollow outer shaft 146 with proximal twist-lok means 142 attached thereto and an inner shaft 148 having distal twist-lok means 144 attached thereto. As shown in FIG. 11, twist-lok means 142,144 may be T-shaped. Twist-lok means 142,144 may alternatively be star-shaped, as shown in FIG. 13. Twist-lok mechanism 140 may have twist-lok means of any other shape that will provide linear movement and permit locking and unlocking of the delivery means from device 100.
Twist-lok mechanism 140 is constructed and arranged to pull ends 114,116 toward center 118 of device 100. Alternatively, this movement may be reversibly effected through any suitable mechanical means, such as screws, ratchet, snap fittings, or tie off procedures, all of which would prevent the device from opening up and resuming a cylindrical shape.
Referring to FIGS. 11-12, inner shaft 148 is rotatably mounted in outer shaft 146 to provide independent rotational movement of proximal and distal twist-lok means 142,144. Inner shaft 148 is also distally extensible from outer shaft 146.
In operation, proximal twist-lok means 142 is rotated counter-clockwise to its resting/delivery position, and is rotated clockwise to un-lock. Distal twist-lok track 132 of device 100 is shown at FIG. 8 with distal twist-lok means 144 therein. The rotational directions of proximal and distal twist-lok means 142, 144 are opposite of each other, so that device 100 may not detach from the delivery system unless twist-lok means 142,144 are rotated.
Subsequent removal of device 100 may be effected by inserting twist-lok mechanism 140 and rotating twist-lok means 142,144 in their respective removal directions to recapture device 100 for un-deployal and removal.
FIGS. 10 and 12 show an optional anchoring means 150a, 150b which may be employed as a safety or reinforcement anchoring means 150a being located at the proximal end 114 of device 100, and anchoring means 150b being located at the distal end 160 of outer shaft 146 of twist-lok means 140. To eliminate rotation, splines 152 located at proximal end 114 of device 100 interlock or press fit into ribs 154 located in the interior of outer shaft 146 of twist-lok means 140. Distal movement of inner shaft 148 will cause distal end 162 of inner shaft 148 of twist-lok means 140 to contact device 100, pushing anchoring means 150a of device 100 away from anchoring means 150 b and out of outer shaft 146 of twist-lok means 140, disengaging splines 152 from ribs 154. Proximal and distal twist-lok bars 142,144 are each capable of movement both distally and proximally depending on their current position, thus allowing for deploying and undeploying before releasing of device 100 altogether.
An alternative embodiment of the closure device according to the present invention is shown at FIGS. 14-17. FIG. 14 shows a perspective view of an alternative embodiment of a device according to the present invention. FIG. 15 shows a perspective view of a pull mechanism whereby the device is transformed into a plug. As shown in FIG. 14, the catheter delivered device, shown generally at 200, comprises a cylindrical shaft 212 having a proximal end 214, a distal end 216, and a central portion 218. Cylindrical shaft 212 has parallel struts 222. Struts 222 may be covered by a cloth or other suitable biocompatible covering.
Pull mechanism 230 comprises shaft 231 with distal pull bar (or twist-lok bar) 232, pull mechanism being constructed and arranged for insert ion into device 200 through proximal opening 233 and distally through distal opening 234, and rotated, as shown at FIGS. 16-17. In the position shown at FIGS. 16-17, pull mechanism 230 can pull distal end 216 toward center 218 and center 218 toward proximal end 214. Alternatively this movement may be reversibly effected through any suitable mechanical means, such as screws, ratchet, snap fittings, or tie off procedures, all of which would prevent the device 200 from opening up and resuming a cylindrical shape.
As shown in FIGS. 16-17, hinge points 225 move radially away from the axis of the device in a hinge like fashion in response to the movement of proximal and distal ends 214, 216 toward the central portion 218 of the device 200. Hinge points 225 could be formed in a variety of ways. Such a hinge point could be a mechanical hinge, a thinned section created by chemical etching, mechanical denting, grinding, heat forming or machining, a weakened section created by micro cuts, tapered grooves, chemical treatment, or any other process which will cause a preferential stress point.
The embodiment shown, in FIGS. 16-17 has three locking locations, center, proximal and distal. Distal end 216 may be locked to central portion 218 by means of distal locking pins 236 constructed and arranged to mate with central locking bores 240, and proximal end 214 may be locked to central portion 218 by means of central locking pins 242 constructed and arranged to mate with proximal locking bores 238. All mating locking surfaces are preferably shaped in such a manner to facilitate locking. Locking pins 236,242 may be ratcheted for the tightest fit. FIG. 17 is a partial view of device 200 showing the manner in which pins 236,242 respectively lock into bores 238,240.
FIGS. 18-20 show deployment catheters with device 100 as shown in FIG. 6. FIG. 18 shows deployment catheter 40 according to the present invention, with control means 300 located at proximal end 41 thereof. Control means 300 has linear slides 310,312, unlock lever 314 and flush port 316. FIG. 19 shows catheter 40 with an alternative embodiment of control means 300, having dual rotation knobs, i.e. proximal rotation knob 320 and distal rotation knob 322. FIG. 20 shows a further alternative embodiment of deployment catheter 40, having a gun-like handle 330 with up and down triggers 332,334, and un-lok slides 336,338.
The septal defect closure devices and apparatus disclosed herein may further comprise a plurality of tissue hooks located thereon to anchor the device in place in a septal defect. For example, FIGS. 21-22 show a sectional view of the device as in FIGS. 14, 16 and 17 further including a plurality of tissue hooks 270.
FIGS. 23-24 show side views of a device as shown in FIGS. 3-4 respectively, the device further including a plurality of tissue hooks 70. FIG. 23 shows an intermediate conformation which the device would assume after delivery and during its mechanical transformation into a plug. FIG. 24 is a side view of the device as in FIG. 23 after its mechanical transformation into a plug. FIG. 25 is an anterior to posterior sectional view showing the septal defect closure device of FIGS. 23-24 after delivery to the atrial and ventricular defects as depicted therein. Device 10 is anchored to the tissue of the septal defect by the physical interaction of tissue hooks 70 therewith.
In a preferred embodiment, distal tip 42 of insertion catheter 40 according to the present invention is made of metal for visualization under fluoroscopy and is shaped in such a manner which does not interfere with the insertion of the twist-lok mechanism or pulling mechanism, fitting flushly with proximal end 14 of closure device 10.
The entire closure device or the portion thereof exposed to the heart chambers may be covered or coated with a fabric and/or elastic material (not shown) which may be biodegradable. This material will block blood shunting across the septal defect and may also allow tissue ingrowth to help in the stabilization of the device. Fabrics with which the mid-section may be coated with are polyamides, such as nylon 6, nylon 6,6, and the like, polyesters, such as PET, polyethers, fluorinated polymers, such as polytetrafluoroethylene, or biodegradable or nonbiodegradable fibers derived from natural sources such as carbohydrates, collagens, and proteins. The fabric may be of a woven knit, or solid structure.
The unique features of the device are the manner of its deployment and its reversibility, its low profile which may prevent interference with normal heart functions, the shape of the support struts, and the non-invasive nature of the delivery which would reduce costs normally associated with closure of such a defect. The device may be made of metal or polymeric material and is delivered via catheter in a non-invasive procedure. The device operates through mechanical means to close a septal defect.
The practice of the present invention achieves several objectives and advantages. The device and method of the present invention provides an advantage over surgery in that the cost of the procedure is substantially less, the risk of infection is less, the hospital residency time is less and there is no physically deforming scar.
Advantages include the flexibility of the reversible deployment, the fact that the non-invasive delivery would reduce costs associated with this type of procedure, the low profile may prevent interference with normal heart functions. Support arms have three support locations which may provide increased support arm strength.
While this invention may be embodied in many different forms, there are described in detail herein specific preferred embodiments of the invention. This description is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated.
The above Examples and disclosure are intended to be illustrative and not exhaustive. These examples and description will suggest many variations and alternatives to one of ordinary skill in this art. All these alternatives and variations are intended to be included within the scope of the attached claims. Those familiar with the art may recognize other equivalents to the specific embodiments described herein which equivalents are also intended to be encompassed by the claims attached hereto. | A catheter delivered device to close a septal defect, the device comprising a cylindrical shaft of metal or polymeric material with concentric parallel cuts through the wall of the device which create flattened support struts. The center of the support struts move radially away from the axis in a hinge like fashion in response to the movement of the device's proximal and distal ends toward the center of the device. This movement is reversibly effected through mechanical means. The device can be coated with growth factors, mitogenic factors or other determinants which can improve tissue growth such that tissue ingrowth can occur over a period of time. The catheter itself may be an ultrasonic imaging catheter. | 0 |
FIELD OF THE INVENTION
The invention relates generally to the transmission and reception of information such as analog audio data over the air. More particularly, the invention pertains to the transmission/reception of high fidelity audio signals over the air over short distances using high frequency carriers at low power.
BACKGROUND OF INVENTION
A number of systems have been developed to avoid wiring stereo speakers directly to the source of signals used to drive the speakers, e.g., phonographs, tape decks, CD players, or AM/FM tuners. By way of example, U.S. Pat. No. 4,829,570, issued to Larry Schotz on May 9, 1991, discloses a system of this type. This system, while not requiring direct wiring between the source of signals and the speaker, transmits the signals over the A.C. electrical conductors of the building in which the system is located. The signals transmitted in this manner are subject to certain undesirable effects, such as filtering for computer systems. This type of filtering may eliminate or degrade the signals intended for transmission to the speakers.
An alternative to using any form of wiring between a speaker and the source of signals for driving the speaker is to transmit the signals over the air via electromagnetic waves such as radio waves. This type of system requires the use of a transmitter for transmitting the signals, a receiver for receiving the signals at the speaker, and a power amplifier for amplifying the signals at the speakers to properly drive the speakers. The drawback with this type of system is that the FCC strictly regulates the frequencies at which information may be transmitted over the air without the requirement of an appropriate license. Additionally, the number of frequencies at which transmission may occur is limited. Currently, the frequency bands available for transmitting information using low power transmission without a license are at high frequency ranges. For example, the FCC currently allows the use of low power transmission (i.e., below 1 milliwatt for conventional modulation or below 1 watt for spread spectrum modulation, 47 CFR §15.249) in the range of 902 to 928 MHz, 2.4 to 2.483 GHz and 5.725 to 5.875 GHz. One such wireless speaker system is disclosed in U.S. Pat. No. 5,299,264 (Schotz et al.) issued on Mar. 29, 1994 and which is also assigned to the same assignee, namely L. S. Research, Inc., as the present invention. Another wireless speaker system is disclosed in U.S. application Ser. No. 08/070,149, assigned to the same assignee as the present invention and whose disclosure is incorporated by reference herein. In particular, the 08/070,149 apparatus is an analog system for transmitting signals from a plurality of audio sources simultaneously over the air using carrier signals in the 902-928 MHz range.
Wireless speaker systems are desirable, since wiring is not required between the speakers and source of signals for driving the speakers; however, an arrangement of this type is not practical if the quality of the information signal driving the speaker is poor. Stereo speaker applications require high signal-to-noise ratios, good frequency response, low distortion, and stereo capability (simultaneous transmission of two channels of information) to be practical. A wireless speaker system is not a replacement for a system using wires unless the quality of information signals provided to drive the speakers results in a sound at the speakers comparable with the sound at similar speakers in a system using wires.
The transmission/reception of audio signals, e.g., music, (approximately 20 Hz to 20 kHz) must be distinguished from the transmission/reception of voice signals (approximately 300 Hz to 3 kHz). The former requires wideband transmission while the latter requires only narrowband transmission.
One implementation of a digital wireless speaker system operating in the 2.4 GHz band is disclosed in U.S. Application Ser. No. 08/344,298, assigned to the same assignee as this invention, namely L. S. Research, Inc., and whose disclosure is incorporated by reference herein.
Accordingly, the need exists for an analog system capable of transmitting and receiving audio over the air using high frequency carriers (e.g., 2.4 GHz) at low power while maintaining the quality of the audio.
OBJECTS OF THE INVENTION
Accordingly, it is the general object of this invention to provide an apparatus which overcomes the disadvantages of the prior art.
It is still a further object of this invention to enable the user to listen to high quality audio in any remote location without external wires or independent equipment.
It is even yet a further object of this system to provide the user with compact disc quality sound through a wireless system.
It is yet another object of this invention to provide a system that can directly transmit the analog audio output available from compact disc players, digital audio tape players, as well as other sources.
It is yet a further object of this invention to provide a system for providing high fidelity sound at low cost.
It is yet a further object of this invention to provide an analog spread spectrum wireless speaker system.
SUMMARY OF THE INVENTION
These and other objects of the instant invention are achieved by providing a high fidelity, wireless transmission, audio system for use with an audio source, the source providing a first electrical input signal and a second electrical input signal and wherein the audio system is arranged for wirelessly transmitting over the air an electrical signal representing the audio input signals. The audio system comprises a transmitter arranged to be coupled to an audio source and comprises multiplexing means for converting the first and second electrical input signals into a first composite electrical signal. The audio system further comprises carrier signal producing means for producing a carrier signal of a predetermined frequency of at least 2.4 GHz and a spread spectrum modulation means for modulating the carrier signal with the first composite electrical signal to produce a modulated carrier signal. The transmitter also comprises a first antenna means for emitting over the air said modulated carrier signal at a power level not exceeding approximately 1 watt. Finally, the audio system comprises a receiver located within a range of approximately 10 to 300 feet (3 to 90 meters) of the transmitter and is coupled to an audio transducing device whereby the receiver receives and demodulates the modulated carrier signal into a second composite signal.
DESCRIPTION OF THE DRAWINGS
Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
FIG. 1 is a diagram of the analog spread spectrum wireless transmission system;
FIG. 2 is a block diagram of the transmitter of the analog spread spectrum wireless speaker system;
FIG. 3 is a block diagram of the receiver of the analog spread spectrum wireless speaker system;
FIG. 4 is a block diagram of the transmitter of the analog spread spectrum wireless speaker system using frequency hopping; and
FIG. 5 is a block diagram of the receiver of the analog spread spectrum wireless speaker system using frequency hopping.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now in detail to the various figures of the drawing wherein like reference characters refer to like parts, there is shown at 20 in FIG. 1, the analog spread spectrum wireless speaker system.
The system 20 comprises a transmitter 22 and a receiver 24, each utilizing respective analog circuitry, similar to respective circuitry of the transmitter and receiver disclosed in application Ser. No. 08/070,149. One type of audio source equipment 26 (e.g., AM/FM tuner, compact disc player, digital audio tape player, etc.) is coupled to the transmitter 22 via coupling means 28. In particular, analog left and right audio channel signals are accommodated on input lines 30A and 30B. The analog circuitry 32 basically modulates a 2.4 GHz carrier frequency signal with the multiplexed analog left and right audio channel signals and prepares a broadcast signal 34 for transmission to the receiver 24. The broadcast signal 34 is transmitted from the transmitter antenna 36 and over the air to the receiver 24.
The receiver 24, located at a remote site (e.g., another room, floor level, etc., in the range of approximately 10 to 300 feet from the transmitter 22), receives the broadcast signal 34 via a receiver antenna 38. The receiver's circuitry 40 then demodulates the audio information from the broadcast signal 34 into respective output signals on lines 42A and 42B that are provided to a coupling means 44 for connection to speakers or other audio transducing equipment 46.
The details of the transmitter circuitry 32 will now be discussed. As shown in FIG. 2, the circuitry 32 comprises 25-kHz notch filters 48A and 48B, low-pass filters 50A and 50B, a stereo matrix encoder 52, a transmitter microprocessor (μP) 54 (or a microcontroller), a 25-kHz pilot signal generator 56, a summer 58 a voltage controlled oscillator (VCO) 60, a binary phase shift keying (BPSK) modulator 62, a spread spectrum signal processor 64 a house code select switch 66, a phase-locked loop 68, a power amplifier 70 and a bandpass filter 72.
At this juncture it should be noted that although the transmitter microprocessor 54 (e.g., ROM-based 8-bit CMOS Microcontroller PIC16CR57A) is used to control the phase-locked loop 68, the microprocessor 54 also controls the stereo matrix encoder 52 and the 25-kHz pilot signal generator 56, as will be discussed later. Although a separate, dedicated microprocessor could be used exclusively for each of these controlled components, the microprocessor 54 is capable of such multi-purpose use within the transmitter circuitry 32.
As shown in FIG. 2, the left and right stereo signals on leads 30A and 30B are both passed through 25-kHz notch filters 48A and 48B, respectively, and low-pass filters 50A and 50B, respectively, before stereo multiplexing. Each notch filter 48A and 48B comprise a notch component that notches out any 25 kHz and 50 kHz signals while each filter 50A and 50B comprises a low pass component that filters any signals higher than 20 kHz. This is done so that no interference is incurred in the stereo multiplexing in the stereo matrix encoder 52.
The filtered left and right audio signals on leads 75A and 75B, respectively, are then fed to the stereo matrix encoder 52 that derives the baseband L+R (Left+Right, 20 Hz-20 kHz) and the double side band suppressed carrier L-R (Left-Right, 30 kHz-70 kHz) signals and outputs these into a single signal on lead 74. The stereo matrix encoder 52 uses a chopper modulator to combine these two component signals on leads 75A and 75B into a single signal. In particular, the chopper modulator comprises a 4066 chip which is a quad bilateral switch that receives 50 kHz switching signals 77A and 77B generated by the microprocessor 54. This performs the chopping function resulting in the single signal comprising the L+R and L-R signals which is then filtered by the stereo matrix encoder 52. This single filtered signal on lead 74 is then summed by the summer 58 with the pilot (25 kHz) to result in the multiplexed stereo signal on lead 78. Thus, the stereo multiplexed signal comprises the baseband L+R signal (20 Hz--20 kHz), the double side band suppressed carrier L-R signal (30 kHz-70 kHz), and a pilot signal (25 kHz) which encompasses a full information bandwidth of 70 kHz.
It should be noted at this juncture that the microprocessor 54 generates a 25-kHz square wave that the pilot signal generator 56 converts into a 25 kHz sinusoidal pilot signal.
This multiplexed signal on lead 78 is fed to, and modulates, the voltage controlled oscillator 60 (VCO, e.g., ZCOMM, V800MC03) using frequency modulation (FM). The frequency of the VCO 60 is controlled by a phase-locked loop 68 (PLL e.g., Motorola MC12210) in conjunction with the house code select switch 66 and the microprocessor 54. The peak frequency deviation from the VCO 60 center frequency is set for optimal tuner performance of the receiver 24. This optimization in the receiver 24 is a tradeoff between Signal to Noise (S/N) ratio, receiver 24 Intermediate Frequency (IF) filter requirements, and bandwidth of the FM tuner.
It should be noted at this juncture that the VCO 60 produces any one of a number of carrier frequencies (e.g., 2.42 GHz, 2.44 GHz and 2.46 GHz). In particular, the user sets the house code select switch 66 (any variable position BCD switch that is located on the outside of the transmitter 22 unit) to a particular setting and this setting information is transmitted to the microprocessor 54 via data line 80. The microprocessor 54 then transmits the corresponding set of frequency data to the PLL 68 (e.g., Motorola MC12210 Serial Input PLL Frequency Synthesizer) on data line 82 which controls the VCO 60 (e.g., Z-Comm SMV2500 Voltage Controlled Oscillator) in generating the particular 2.4 GHz carrier frequency for the BPSK modulator 62. The microprocessor 54, house code select switch 66, PLL 68 and VCO 60 operate in accordance with a similar transmitter local oscillator circuitry as disclosed in U.S. Application Ser. No. 08/070,149. However, in the present application, spread spectrum modulation is used in conjunction with these components, as will be discussed below.
The carrier frequency for the system is in the 2.4-2.4835 GHz band for several reasons. First, interference in this band is significantly reduced relative to other bands. Second, the available bandwidth meets the transmission requirements. Lastly, at 2.4 GHz, the antenna size (i.e., transmitter antenna 36 and receiver antenna 38) is much smaller and less obtrusive to the user. Furthermore, it should also be pointed out that use of spread spectrum modulation techniques in the 2.4 GHz band are allotted up to 1 watt of transmitting power rather than only the 1 milliwatt of power allotted for non-spread spectrum modulation. 47 CFR §15.249.
The transmission frequencies of 2.42 GHz, 2.44 GHz and 2.46 GHz are exemplary only and are not meant to limit the present invention to those particular frequencies in the available 2.4 GHz band.
As shown in FIG. 2, the FM output of the VCO 60 on lead 84 is then fed to the BPSK modulator 62 (e.g., RF Micro Devices RF2422) where it is mixed with the pseudo-noise (PN) code on lead 86 from the spread spectrum signal processor 64. The process of introducing the PN code after the VCO 60, or RF spreading, allows analog modulation to be used. Typical systems mix the PN code with digitized data before modulating the VCO 60. The PN code is generated from a commercially available spread spectrum signal processor 64, such as the Atmel AT48802, thereby implementing a direct sequence (DS) spread spectrum. Using spread spectrum implies that the RF spectrum is much wider than the transmitted information and that some other function other than the information being sent is used to determine the resulting modulated RF bandwidth. By utilizing spread spectrum, the system has several inherent advantages such as longer range transmissions and interference rejection, thereby yielding higher audio performance. In addition, by using a different spreading function, different channels can be received in the same frequency band.
The microprocessor 54 loads all of the internal control registers of the spread spectrum signal processor 64 via interface lead 89. These registers control the PN codes and an internal correlator, as well as other supervisory functions, i.e., basically setting up all of the link conditions for the PN code and timing.
Finally, the modulator 62 output on lead 88 is amplified by the power amplifier 70 (e.g., Teledyne MMIC TAE-1020) and then passed through the bandpass filter 72 for removing undesired harmonics. The filtered signal is then fed into the transmitter antenna 36 from lead 90. The broadcast signal 34 is emitted at a power level that is in compliance with 47 CFR §15.249, the FCC requirement for wireless transmission in the 2.4-2.483 GHz frequency band using spread spectrum.
The details of the receiver circuitry 40 will now be discussed. As shown in FIG. 3, the receiver analog circuitry 40 comprises a first image bandpass filter 92, a low-noise amplifier 94, a second image bandpass filter 96, a first down-converter mixer 98, a first local oscillator 100, a BPSK demodulator 102, a receiver microprocessor 104, a phase-locked loop 106 (PLL), a house code select switch 105, a spread spectrum signal processor 108, a first bandpass filter 110, a first intermediate frequency (IF) amplifier 112, a second local oscillator 114, a second down-converter mixer 116, a second IF bandpass filter 118, an FM tuner 120 and left lowpass filter 122A and a right lowpass filter 122B.
The incoming broadcast signal 34 is fed from the receiver antenna 38 to a first image bandpass filter 92, through a low noise amplifier 94 (e.g., Hewlett-Packard MGA-86576) and through a second image bandpass filter 96. The purpose of these image bandpass filters 92 and 96 is to attenuate incoming signals that are at the image frequency of the first local oscillator 100. The bandpass filters 92 and 96 can be implemented with a variety of conventional filter circuits or by commercial filters such as the Sawtek 851541 SAW filter. This filtered signal on lead 124 is fed into the first down-converter mixer 98.
The local oscillator VCO 100 (e.g., ZCOMM, V800MC03), the receiver microprocessor 104 (e.g., ROM-based 8-bit CMOS Microcontroller PIC16CR57A), the PLL 106 (e.g., Motorola MC12210 Serial Input PLL Frequency Synthesizer), and the house code select switch 105 operate in accordance with a similar receiver local oscillator circuit as disclosed in U.S. Application Ser. No. 08/070,149. In particular, the user sets the house code select switch 105 (any variable position BCD switch located on the outside of the receiver 24 unit) to the corresponding setting of the transmitter house code select switch 66 and this setting information is transmitted to the microprocessor 104 via data line 126. The microprocessor 104 then transmits the corresponding set of frequency data to the PLL 106 on data line 128 which controls the first local oscillator 100 in generating a first local oscillator signal in the 2.4 GHz band on lead 130.
The first local oscillator signal on lead 130 is fed to the BPSK demodulator 102 (e.g, an RF2422) where it is mixed with a PN code on lead 132. This PN code is generated by the spread spectrum signal processor 108 (e.g., Atmel AT48802 Spread Spectrum IC). The spread spectrum signal processor 108 receives a received-signal strength signal on lead 134 from the second IF bandpass filter 118 which is used by the spread spectrum signal processor 108 to determine the PN code timing. Hence, the correct PN code timing correlates to the strongest signal. Furthermore, much like the transmitter microprocessor 54, the receiver microprocessor 104 also loads all of the internal control registers of the spread spectrum signal processor 108 via interface lead 135 for the same reasons discussed earlier. In addition, the receiver microprocessor 104 controls the spread spectrum signal processor 108 synchronization and tracking relating to acquisition of the PN code.
The output signal from the BPSK demodulator 102 on lead 136 is mixed with the filtered signal on lead 124 in the first down-converter mixer 98 (e.g., Hewlett-Packard Mixer, IAM-82008) to perform the first down-conversion to the first IF, thereby creating a first IF signal on lead 138. At this juncture it should be noted that the introduction of the PN code before the first down-conversion, or RF de-spreading, results in a more narrow IF channel than is used in typical DS spread spectrum systems. This results in a higher level of interfering signal immunity and lower system noise. On the other hand, conventional DS spread spectrum systems that perform the de-spreading at baseband require a much wider IF bandwidth.
The first IF signal on lead 138 is fed through a first IF bandpass filter 110 and then into a second down-conversion comprising the first IF amplifier 112, the second local oscillator 114 and the second down-converter mixer 116. The first IF amplifier 112 and the second down-converter mixer 116 can be implemented using an RF2401 Low Noise Amplifier/Mixer. As shown in FIG. 3, the second local oscillator 114 comprises a 255 MHz oscillator circuit which generates a second local oscillator signal on lead 139 that is used to down-convert the first IF signal to a second IF signal (70 MHz) that can be demodulated by a conventional FM tuner. As shown in FIG. 3, the second IF signal on lead 140 is passed through the second IF bandpass filter 118 and fed into the FM tuner 120 (e.g., TA8122 FM Tuner). The FM tuner 120 performs the demodulation of the broadcast signal 34 into a composite signal which is then demultiplexed into the corresponding left and right channel stereo signals. In particular, the 70 MHz signal on lead 140 is fed to the FM tuner 120 where it is mixed on board the FM tuner 120 and the signal is down-converted to a 10.7 MHz IF. The FM tuner 120 then demodulates the stereo FM signal into a left channel and a right channel on leads 142A and 142B. These two channel signals are then de-emphasized and filtered by low pass filtering circuits 122A and 122B. Once filtered these two channels are provided on output left channel lead 42A and right channel output lead 42B to the receiver coupling means 44.
Both the transmitter 22 and the receiver 24 have respective power circuits (not shown) that convert input power (e.g., 120 VAC at 60 Hz) into proper voltage levels for appropriate transmitter and receiver operation.
FIGS. 4 and 5 show an analog frequency hopping (FH) spread spectrum transmitter/receiver system. In particular, FIG. 4 shows the FH transmitter circuitry 144 while FIG. 5 shows the FH receiver circuitry 146. Operation of the DS transmitter circuitry 32 in FIG. 2 and operation of the FH transmitter circuitry 144 in FIG. 4 are similar except for the modulation stage, as will be discussed below. Operation of the DS receiver circuitry 40 in FIG. 3 and operation of the FH receiver circuitry 146 in FIG. 5 are similar except for the generation of the first local oscillator 100 signal on lead 130, as will also be discussed below.
The FH transmitter circuitry 144 (FIG. 4) replaces the spread spectrum signal processor 64 in the DS transmitter circuitry 32 (FIG. 2) with a second phase locked loop (PLL) 148 and a second voltage controlled oscillator (VCO) 150 for generating a signal on lead 152 that constantly changes in accordance to a hopping sequence. The hopping sequence comprises a PN code that is stored in the transmitter microprocessor 54. The microprocessor 54 systematically loads the PLL 148 (e.g., Motorola MC12210) via data line 154 according to the hopping sequence to change the frequency of the second VCO 150 (e.g, any commercially-available VCO). The FM output of the VCO 60 (comprising the multiplexed stereo signal) on lead 84 is then mixed with the signal on lead 152 in a mixer 156 (any commercially-available mixer). The resulting signal on lead 158 is a modulated frequency hopping carrier signal in the range of 2.4-2.4835 GHz. This modulated frequency hopping carrier signal is then fed to a bandpass filter 160 that eliminates unwanted signals resulting from the mixing process in mixer 156. This filtered signal on lead 162 is then fed to the power amplifier 70, as discussed previously.
The FH receiver circuitry 146 (FIG. 5) eliminates the BPSK demodulator 102 and replaces the spread spectrum signal processor 108 in the DS receiver circuitry 40 (FIG. 3) with a synchronization circuit 164. Therefore, the output of the first local oscillator 100 on lead 130 directly feeds the first down-converter mixer 98. Generation of the first local oscillator 100 signal on lead 130 in the FH receiver circuitry 146 is as follows: The house code select switch 105 setting determines the reference frequency in the 2.4 GHz band, as was discussed earlier with respect to the DS receiver circuitry 40. Furthermore, in the FH receiver circuitry 146, the receiver microprocessor 104 also contains the PN code that is found in the transmitter microprocessor 54. The receiver microprocessor 104 also must switch this first local oscillator 100 reference frequency in accordance with the transmitter frequency hopping sequence. Once the FH receiver circuitry 146 and the FH transmitter circuitry 144 are synchronized, the filtered signal on lead 124 (the multiplexed stereo signal) can be down-converted and demodulated, as discussed previously with respect to the DS receiver circuitry 40. The synchronization is achieved by the synchronization circuit 164 monitoring the output from the second IF bandpass filter 118 on lead 134, as discussed earlier with respect to the DS receiver circuitry 40. When the FH receiver circuitry 146 and the FH transmitter circuitry 144 both are at the correct frequency, the synchronization circuit 164 provides a control signal on lead 166 to the microprocessor 104 that keeps the timing of the FH receiver circuitry 146 hopping sequence the same as the FH transmitter. If the FH transmitter circuitry 144 frequency and the FH receiver circuitry 146 frequency are different, the synchronization circuit 164 generates an error signal on lead 166, thereby informing the FH receiver microprocessor 104 to change the frequency hopping sequence of the first local oscillator 100. Thus, once the FH receiver circuitry 146 is locked, the frequency hopping sequence does not change and when the FH receiver circuitry 146 is not locked, the frequency hopping sequence dynamically changes until lock is achieved.
Without further elaboration, the foregoing will so fully illustrate the invention that others may, by applying current or future knowledge, adopt the same for use under various conditions or service. | An analog spread spectrum wireless speaker system for use in consumer audio applications for providing reliable and high fidelity stereo sound. The system includes a transmitter that accommodates any analog input from a variety of audio devices such as compact disk players, cassette players, AM/FM tuners and transmits this information in the 2.4-2.4835 GHz band to a receiver at a remote location. The receiver is capable of reproducing the audio signal with good frequency and signal-to-noise performance. | 7 |
BACKGROUND
Main landing gears may be installed in an aircraft during or after final body join. Each main landing gear may be mounted to spars or other primary structural members of a wing.
Consider the example of a large commercial jetliner in which each main landing gear weighs tens of thousands of pounds and, when upright, exceeds aircraft working height. Clearances for moving the main landing gear through an opening in the wing's skin, and positioning the main landing gear at a mounting location at a spar, are very tight. If the main landing gear bumps into the skin or spar, it can damage the skin or spar. The damage can be expensive in terms of money and time, especially if production is delayed.
Some aircraft factories have pits for installing main landing gears. An upright landing gear is loaded into the pit, the aircraft is moved over the pit, and the upright landing gear is raised until its load bearing interfaces arrive at their mounting locations.
If a pit is not available, a landing gear loader may be used to position a main landing gear underneath a wing, and translate and tilt the landing gear until its load bearing interfaces arrive at their mounting locations. However, this process involves a series of discrete movements. After each discrete movement, a visual inspection is performed to determine whether there is sufficient clearance. Installation time is prohibitive.
SUMMARY
According to an embodiment herein, a method of loading a landing gear in an aircraft comprises accessing an ideal path specifying movement of the landing gear from a starting location to an expected mounting location on the aircraft; determining a difference between the expected mounting location and an actual mounting location on the aircraft; modifying the ideal path to move the expected mounting location to the actual mounting location; and moving the landing gear along the modified path.
According to another embodiment herein, a system for loading a landing gear in an aircraft comprises a multi-axis loader for rotating and translating the landing gear; and a controller programmed to access an ideal path for commanding the loader to move the landing gear from a starting location and orientation to an ending orientation at an expected mounting location. The controller is further programmed to receive information about an actual mounting location in the aircraft, and modify the ideal path so the loader moves the landing gear from the starting orientation and location to the ending orientation at the actual mounting location instead of the expected mounting location.
These features and functions may be achieved independently in various embodiments or may be combined in other embodiments. Further details of the embodiments can be seen with reference to the following description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of an aircraft.
FIG. 2 is an illustration of a main landing gear of an advanced commercial aircraft.
FIG. 3 is an illustration of a method of loading a main landing gear in an aircraft.
FIGS. 4A-4C are illustrations of a loading system for loading a landing gear in an aircraft.
FIG. 5 is an illustration of a method of loading a landing gear in an aircraft in a factory.
DETAILED DESCRIPTION
Reference is made to FIG. 1 , which illustrates an aircraft 100 including a fuselage 110 , wings 120 , and an empennage 130 . The aircraft 100 further includes landing gear, which supports the entire weight of the aircraft 100 during landing and ground operations. The landing gear includes main landing gears 140 attached to spars and and/or other primary structural members of the wings 120 . The landing gear may also include a front landing gear attached to a keel of the fuselage 110 .
Additional reference is made to FIG. 2 where the aircraft 100 is on a surface 150 that may be a factory floor, runway or other flat surface as discussed below. In an advanced commercial jetliner, each main landing gear 140 may weigh tens of thousands of pounds. When upright, each main landing gear 140 may exceed aircraft working height.
Each main landing gear 140 typically includes struts, fairings, gear actuators, support units, steering systems, and wheel and brake assemblies. Each main landing gear 140 may further include primary load bearing interfaces such as a forward trunion H-block fitting 160 and a rear trunion fitting 162 ( FIGS. 4A-4C ).
During installation of a main landing gear 140 to a wing 120 the main landing gear 140 is “loaded.” The process of loading the main landing gear 140 is to index and affix its load bearing interfaces (e.g., the forward trunion H-block fitting 160 and the rear trunion 162 ) to mounting locations on primary structural members of the wing 120 . For instance, the forward trunion H-block fitting 160 is attached to a rear spar 460 of the wing 120 , and the rear trunion 162 is pinned to a landing gear beam 462 ( FIGS. 4A-4C ). Additional structural and articulation features may be attached after the landing gear 140 is loaded but before it is ready to bear weight.
The main landing gear 140 may be loaded by a multi-axis loader. The multi-axis loader may translate the main landing gear 140 along a primarily forward axis while translating and rotating the main landing gear 140 about other axes.
Reference is now made to FIG. 3 , which illustrates a general method of using the multi-axis loader to load the main landing gear 140 in the aircraft 100 . At block 300 , the main landing gear 140 is placed in the multi-axis loader. At block 310 , the multi-axis loader moves the main landing gear 140 to a starting location and orientation, alongside the aircraft 100 . If the method is performed in a factory, the multi-axis loader moves the main landing gear 140 along the floor 150 of the factory.
At block 320 , prior to loading, an ideal path is accessed. The ideal path specifies location and orientation of the main landing gear 140 as the multi-axis loader moves it from the starting orientation and location to an expected mounting orientation and location. If the actual mounting location is at its expected location, and if the main landing gear 140 follows the ideal path during loading, then the load bearing surfaces 160 , 162 of the main landing gear 140 will arrive at the actual mounting locations on the primary structural members 460 , 462 of the aircraft 100 . Moreover, if the main landing gear 140 follows the ideal path, and if the actual mounting location is where it is expected, then the main landing gear 140 will arrive without bumping into any portion of the aircraft 100 or any other constraints during loading.
The ideal path may be computer-generated from a simulation based upon computer-aided design (CAD) models of the landing gear 140 , and the aircraft 100 , and any other constraints (e.g., factory surfaces, surrounding access platforms and other equipment, expected locations of people during loading). The simulation may also produce machine commands that cause the multi-axis loader to move the main landing gear 140 from the starting orientation and location and follow the ideal path to the expected mounting orientation and location. Thus, the ideal path may be represented as coordinates of a local coordinate system, or as machine commands. The coordinate system may be defined by the multi-axis loader.
However, the actual mounting location might not be where it is expected. For instance, there might be positioning errors of the aircraft 100 , the landing gear 140 and the multi-axis loader. The factory floor 150 might be uneven or not level.
At block 330 , a difference between the actual mounting location and the expected mounting location on the aircraft 100 is determined. After the difference has been determined, the aircraft 100 is not allowed to move until the landing gear 140 has been loaded. Although FIG. 3 shows block 320 occurring before block 330 , a method herein is not so limited. The difference may be determined before, during or after the ideal path is accessed.
At block 340 , the ideal path is modified to move the expected mounting location to the actual mounting location. As a first example, any position errors are treated as an offset of the expected mounting location, and the ideal path is modified to correct the offset. As a second example, mathematical methods are used to compensate from axes of the ideal path to the loader's functional axes. If the loader is parked with its forward axis 0.5 degrees off from a forward axis of the ideal path, the x and y components of the ideal path are modified to be in the correct relation to the aircraft 100 .
At block 350 , the multi-axis loader moves the landing gear 140 along the modified path. The landing gear 140 is moved from its starting orientation and location to the actual orientation and location. As the landing gear 140 is moved, its load bearing interfaces 160 , 162 fit through an opening in lower skin of the aircraft 100 and are positioned at the actual mounting location on a primary structural member 460 , 462 , all without bumping into any portion of the aircraft 100 or any other constraints.
As the landing gear 140 is being loaded, its actual location and orientation may be tracked. For instance, a scanning system may track discrete points on the landing gear during loading. Knowledge of the actual location and orientation may be used to improve the accuracy of loading the landing gear 140 . For instance, the tracked points may be compared to the modified path, and loader commands may be adjusted to reduce error between the modified path and the actual orientation and location of the landing gear 140 .
At block 360 , load bearing interfaces 160 , 162 of the main landing gear 140 are affixed to primary structural members 460 , 462 of the aircraft 100 . As the main landing gear 140 is being affixed, the loader continues to support the main landing gear 140 . The load bearing interfaces 160 , 162 are typically large bore, tight tolerance interfaces. The multi-axis loader may also have a functionality to allow a mechanic to “bump” the main landing gear 140 relative to the primary structural members 460 , 462 . The bumping creates very small movement to allow tight bore pins to fit.
In the method of FIG. 3 , the expected mounting orientation is not necessarily upright. For instance, the main landing gear 140 may be loaded in a stowed or partially stowed orientation.
The method of FIG. 3 may be used to install the main landing gear 140 in a factory during or after final body join. However, the method is not so limited. The method of FIG. 3 may be performed on an aircraft outside of a factory. As but one example, main landing gear 140 of an aircraft 100 may be replaced while the aircraft 100 is on a runway or other flat surface 150 of an airport. In this example, the aircraft 100 is supported while the main landing gear 140 is removed from the aircraft 100 . The multi-axis loader may be used to “walk” the main landing gear 140 out of position. The ideal path would be the same, but performed backwards, to avoid collisions upon exit. After the main landing gear 140 has been removed, the multi-axis loader moves replacement main landing gear 140 to a starting location and orientation, and loads the replacement main landing gear 140 according to blocks 320 to 360 .
Reference is made to FIGS. 4A-4C , which illustrate an example of a loading system 410 for loading the landing gear 140 according to the method of FIG. 3 . The loading system 410 includes a multi-axis loader 420 . The multi-axis loader 420 includes first and second linear rails 430 that are straight and parallel to each other. The linear rails 430 define forward functional x-axes. The linear rails 430 are intended to provide a straight path alongside the aircraft 100 .
The linear rails 430 may be configured for mobility. For example, wheels, air bearings or castors may be mounted underneath the linear rails 430 .
The multi-axis loader 420 further includes a first pair of first and second loading towers 440 and 445 for the first linear rail 430 , and a second pair of first and second loading towers 440 and 445 for the second linear rail 430 . Each loading tower 440 and 445 of each pair is independently movable along its linear rail 430 . Linear motion along the linear rails 430 may be achieved with machine screw components (e.g., roller screw, ball screw, or acme screw), a rack and pinion type system (e.g., roller rack, belt system, or traditional sliding friction point), an electromagnetic linear motor, a pressured cylinder system (hydraulic or pneumatic), or other linear drive system.
The multi-axis loader 420 further includes a first beam 450 mounted to the first pair of loading towers 440 and 445 , and a second beam 450 mounted to the second pair of loading towers 440 and 445 (one of the beams 450 is shown most clearly in FIG. 4C ). Each loading tower of each pair is mounted to its corresponding beam 450 at a mounting point. Each mounting point is linearly and independently movable along its corresponding loading tower 440 or 445 in a vertical y-axis. Linear motion may be achieved with machine screw components, a rack and pinion type system, an electromagnetic linear motor, a pressured cylinder system, or other linear drive system.
When the main landing gear 140 is placed in the multi-axis loader 420 , there is a beam 450 on each side of the main landing gear 140 . The main landing gear 140 is mounted to the beams 450 , for example, by pinching tires of the main landing gear 140 from above and below with wheel chalks 460 .
Through independent movement of the loading towers 440 and 445 along the linear rails 430 , and through independent movement of the mounting points along the loading towers 440 and 445 , the main landing gear 140 may be translated and tilted with respect to multiple axes.
The ideal path may be determined with respect to a local coordinate system of the multi-axis loader. The linear rails 430 define x-axes of the coordinate system, and the loading towers 440 and 445 define y-axes of the coordinate system.
FIG. 4A shows the multi-axis loader 420 with the main landing gear 140 in the starting location and orientation. The main landing gear 140 is retracted and tilted.
FIG. 4B shows the main landing gear 140 being walked under a wing 120 (the spar 460 and landing gear beam 462 of the wing 20 are shown in phantom). Each pair of loading towers 440 and 445 is slid together along the linear rails 430 in a forward direction.
FIG. 4C shows the landing gear 140 at the end of the modified path, after having been walked under the aircraft 100 . The first loading towers 440 are moved ahead of the second loading towers 445 , causing the main landing gear 140 to tilt into an upright position. The forward trunion H-block fitting 160 of the main landing gear 140 is now in position to be attached to the rear wing spar 460 , and the rear trunion 162 is now in position to be pinned to the landing gear beam 462 .
At all times, the front wheels of the landing gear 140 are on the floor 150 so as to support some of the weight of the landing gear 140 . After the main landing gear 140 has been tilted to the upright position, all of its wheels are on the floor 150 .
Operation of the multi-axis loader 420 may be controlled by a controller (not shown). The controller accesses commands for the linear drive systems of the multi-axis loader 420 , modifies the commands to account for a difference between the expected and actual mounting locations, and sends the modified commands to the linear drive systems to move the main landing gear 140 along the modified path. The controller may be mounted to the multi-axis loader 420 to form a cohesive whole. Alternatively the controller may be implemented as part of a higher level cell-controller.
The loading system 410 may further include a metrology system 470 (shown in FIG. 4B ), such as radar, laser tracker or vision-based motion capture. The metrology system 470 can measure the distance to specific points (e.g., features) on the actual mounting locations on the rear spar 460 and landing beam 462 . Examples of these specific points may include landing gear mounting points, tooling balls on the loader, side of body fittings, assembly pin locations, retroreflective monuments, and surface-mounted photogrammetric targets. The metrology system 470 can also measure the distance to specific points on the linear rails 430 of the multi-axis loader 420 . The metrology system 470 may also measure the distance to specific points on the main landing gear 140 as the main landing gear 140 is being loaded. Given this information, the controller can determine the difference between the expected and actual mounting locations.
Reference is now made to FIG. 5 , which illustrates a method of using the loading system 410 in a factory to load main landing gear 140 in an aircraft 100 . The factory has a floor 150 that is relatively flat. The factory floor 150 may have indexing marks for positioning the aircraft 100 . For example, the indexing marks may include paint stripes for indicating the position of the aircraft 100 on the factory floor 150 .
The factory floor 150 may also have having indexing 480 for positioning the multi-axis loader 420 relative to the aircraft 100 . As a first example, indexing pins (not shown) may protrude from the factory floor 150 . As a second example, paint stripes 480 ( FIGS. 4A-4C ) on the factory floor 150 indicate the position of the multi-axis loader 420 .
At block 500 , the main landing gear 140 is placed in the multi-axis loader 420 . For instance, the landing gear 140 may be placed in the multi-axis loader 420 by an overhead crane or forklift.
At block 510 , the multi-axis loader 420 retracts and tilts the main landing gear 140 to its starting location and orientation.
At block 520 , the aircraft 100 and the multi-axis loader 420 are moved along the factory floor 150 to their respective designated positions and parked. The multi-axis loader 420 may be moved across the factory floor 150 by means such as an omni-directional crawler or a tug. If the factory floor 150 has indexing pins, the linear rails 430 of the multi-axis loader 420 may engage the indexing pins to establish a precise location on the factory floor 150 . The multi-axis loader 420 is now dimensionally stable, and its linear rails 430 will not be moved until the method has been completed. The aircraft 100 may be parked prior to parking the multi-axis loader 420 , or the multi-axis loader 420 may be parked prior to parking the aircraft 100 .
At block 530 , scaffolding, stands, and other temporary movable equipment (TME) are moved across the factory floor 150 and positioned relative to the aircraft 100 and the multi-axis loader 420 . TME such as scaffolding and stands may be used to fasten the landing gear 140 to the aircraft 100 and attach additional structural and articulation features after the landing gear 140 has been loaded but before it is ready to bear weight. The TME may also be used to perform or complete a wing-to-fuselage join.
At block 540 , the metrology system 470 is used to determine the difference between actual mounting locations and expected mounting locations on the aircraft 100 . The difference is supplied to the controller. If the actual mounting locations are obscured by aircraft skin, tooling may be indexed to the actual mounting locations. The tooling may serve as a proxy to give points with lines of sight.
At block 550 , the controller modifies the ideal path to move the expected mounting locations to the actual mounting locations. At block 560 , the controller commands the multi-axis loader 420 to move the landing gear 140 to follow the modified path.
At block 570 , load bearing interfaces 160 , 162 of the main landing gear 140 are affixed to primary structural members 460 , 462 of the aircraft 100 . The multi-axis loader may hold the main landing gear 140 in place while the load bearing interfaces 160 , 162 are being affixed.
At block 580 , the multi-axis loader 420 is detached from the main landing gear 140 . For instance, the wheel chalks 460 may be removed. The multi-axis loader 420 is then retracted.
Thus, the main landing gear 140 is loaded above grade at current aircraft working height without having to raise the aircraft 100 . A series of discrete movements of the main landing gear 140 is eliminated during loading. As a result, loading time is reduced significantly.
The method of FIG. 5 eliminates the need for pits and other fixed structures on a factory floor 150 . This, in turn, minimizes impact to the rest of the factory. It also enables floor space to be reconfigurable. This flexibility allows for a production line to be adjusted and optimized. Work can be balanced across multiple cells, and the location of each work cell may be shifted, by a couple feet or by a full airplane length.
The floor area for installing the landing gear may be shared with several labor intensive activities, including side of body join, fuselage joins, and aircraft equipment fitting. Having the loading accurately staged ahead of time allows the landing gear to be loaded without a risk of collision and with increased ergonomic access.
The method of FIG. 5 is not limited to main landing gear 140 . For instance, the method of FIG. 5 may be applied to front landing gear.
The methods and system above are not even limited to landing gear. For instance, the multi-axis loader may be used to install objects such as boat propellers, motors, and munitions. | A method of loading a landing gear in an aircraft comprises accessing an ideal path specifying movement of the landing gear from a starting location to an expected mounting location on the aircraft; determining a difference between the expected mounting location and an actual mounting location on the aircraft; modifying the ideal path to move the expected mounting location to the actual mounting location; and moving the landing gear along the modified path. | 1 |
RELATED APPLICATION
The present application claims the benefit of U.S. Provisional Application Nos. 60/258,668, filed Dec. 28, 2000, and 60/220,743, filed Jul. 26, 2000, both applications being incorporated herein in their entirety by reference.
FIELD OF THE INVENTION
The invention relates to an attachment for a telescopic sight for a firearm that enables focusing of the sight without removing the hand from the normal shooting position. The invention may be adapted for any other focusable optical device.
BACKGROUND OF THE INVENTION
When using a gun with a telescopic sight it is often necessary to focus the sight for targets at different shooting distances. Commonly, the telescopic sight has a focusing ring near the ocular end for accomplishing this task.
To focus currently available telescopic sights, one hand must be removed from its shooting position and used to manipulate the focusing ring. This movement disturbs the marksman's concentration and may induce loss of sight of the target. In the case of a hunter stalking game it may create enough movement or noise to spook the game. Additionally, game is often barely seen among foliage or other obstructions. Losing sight of the game momentarily may result in loss of the opportunity to take a shot at it.
A variety of efforts have been made to address this problem. For example, U.S. Pat. No. 5,180,875 issued to Berry, Jr. et al. relates to a scope adjustment for firearms including a thumb wheel for focusing the scope with the marksman's trigger hand.
U.S. Pat. No. 5,276,554 issued to Nassivera discloses a magnification adjustment system for a variable power rifle scope. The device includes a multi-purpose lever which may be manipulated by the thumb of a marksman's trigger hand for adjusting the focus of the scope.
U.S. Pat. No. 5,521,757 issued to Olson relates to an adjustment lever that may be pushed to rotate the adjustment ring.
U.S. Pat. No. 5,528,847 issued to Fisher et al. discloses a variable power telescopic sight.
U.S. Pat. No. 5,020,262 issued to Pena describes a camera mount for rifle scopes whereby the camera is activated when the rifle trigger is pulled.
U.S. Pat. No. 4,290,219 issued to Boller et al. teaches a target sight recording apparatus.
U.S. Pat. No. 5,942,211 discloses a clamping ring with an extended handle dimensioned to be secured to the adjustment ring on a rifle scope. The extended handle includes a remote ring for receiving a finger to manipulate the adjustment ring. All of the above mentioned patents disclose devices that must be manipulated by the marksman's trigger hand. This still tends to break the marksman's concentration and may create enough movement to spook game. Also, many of these devices create substantial obstruction in the area of the rifle where the marksman may need to manipulate either a bolt action or other mechanical parts of the firearm.
The '211 patent also discloses but does not claim a battery operated motor and wired switch assembly that is connectable to the adjustment ring of a scope. The switch may be located on the firearm and manipulated as needed to adjust the scope. This approach is limited by the encumbrance of the wired switch. The wires must be run from the switch assembly to the motor and may interfere with the operation of the moving parts of the weapon. Further, the wired switch is difficult to relocate as desired, for example, a variety of marksmen might use a single firearm each desiring a different location for the switch.
It would be beneficial for a marksman to be able to focus a telescopic sight while keeping his hands in place on the weapon stock and without disturbing the marksman's aim or his potential target. Further, it would be beneficial if the controller for the focusing mechanism A could be placed at any desired location on the firearm and not create obstruction involved in mechanical or wired connection to the scope.
SUMMARY OF THE INVENTION
The present invention solves the above noted problems by providing a motorized, finger operated mechanism for focusing a telescopic sight. The power focusing device generally includes a battery powered motorized focus mechanism operably attachable to the focusing ring of a telescopic sight, a wireless receiver and a controller. The operator controls the focusing mechanism by manipulation of the controller.
The focus mechanism includes a motor, a reduction drive, a power source and a device to engage the focusing ring. The focus mechanism may be secured to an existing telescopic sight or integrated into the telescopic sight design.
The controller includes a switch by which the focus mechanism may be operated in either of two directions. The controller may be positioned in any location convenient to the fingers of the marksman. An additional focus mechanism may be employed to operate a different sight function, for example, to operate a zoom mechanism. The wireless receiver receives commands from the controller, preferably via infrared media. The receiver includes a motor driver that activates the motor in response to the command received and adjusts the telescopic sight parameter in response.
Thus, the operator of the power focusing device may adjust the focus, zoom or other parameter of a telescopic sight without significant movement that is likely to disturb his aim or spook the game that is his intended target.
GRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a power focus attachment as utilized on a telescopic rifle sight;
FIG. 2 is a side plan view of the power focus attachment as utilized on a rifle mounted telescopic sight;
FIG. 3 is a rear plan view of the power focus attachment as utilized on a rifle mounted telescopic sight;
FIG. 4 is a fragmentary sectional view of the housing and contents;
FIG. 5 is a block diagram of a controller as utilized in the present invention;
FIG. 6 is an exemplary schematic circuit diagram of the controller of FIG. 5;
FIG. 7 is a block diagram of a wireless receiver as utilized in the present invention; and
FIG. 8 is an exemplary schematic circuit diagram of the wireless receiver of FIG. 7 .
DETAILED DESCRIPTION OF THE INVENTION
The power focusing device 10 depicted in FIGS. 1, 2 and 3 generally includes a focuser 12 and a controller 14 . The controller 14 is mounted on a telescopic sight 16 which is in turn mounted on a firearm 18 . The firearm 18 may be a rifle, a hand gun or another similar weapon such as a crossbow. The firearm 18 described and depicted herein is a rifle but this should not be construed as limiting. Additionally, this application will refer to focusing the telescopic sight, however, it is to be understood that the power focusing device may be used to control any adjustable parameter of the scope. These may include a zoom mechanism, windage adjustment or elevation adjustment. The power focusing device 10 is intended to be universally adaptable to telescopic sights and spotting scopes.
The telescopic sight 16 includes an objective lens 20 , an eyepiece 22 , a barrel 24 and a focusing ring 26 . The firearm 18 includes a forestock 28 , a trigger guard 30 and a pistol grip 32 .
The focuser 12 includes a housing 34 , brackets 36 , a pulley 38 and a belt 40 . The housing 34 is secured to the barrel 24 of the telescopic sight 16 via brackets 36 . Pulley 38 is operably engaged to focusing ring 26 by belt 40 . Belt 40 , focusing ring 26 and pulley 38 may include meshing teeth (not shown).
Referring to FIG. 4, enclosed within housing 34 are power supply 42 , motor 44 , reduction drive 46 and power shaft 48 . Motor 44 is reversible. Power supply 42 is electrically connected to motor 44 . Motor 44 turns reduction drive 46 which in turn rotates power shaft 48 which is operably connected to pulley 38 . Housing also contains wireless receiver 50 .
Power supply 42 may be a battery or other power source. The motor 44 and reduction drive 46 are preferably a Maxon A max 119070 p07 motor and a Maxon A max 122.6:1 gear head.
The controller 14 includes a switch 52 . The switch 52 may be any switch with two momentarily closed positions. Advantageously, switch 52 includes two momentary contact push button switches 53 . The first closed circuit activates focuser 12 in a first direction. The second closed position activates focuser 12 in a direction opposed to the first. Preferably, switch 52 includes two momentary push button contact switches each activating the focuser in one direction. Another style of switch may also be employed so long as it allows an appropriate number of momentary contact circuits for the desired focuser functions.
The controller 14 may be placed in any location on or near to the firearm 18 that is readily reachable by the marksman. For example, the controller may be conveniently located on or in the vicinity of the trigger guard 30 and controlled by the marksman's trigger finger (not shown). Preferably, the controller 14 may be located on the forestock 28 or pistol grip 32 of a rifle or pistol in any location convenient to the marksman.
The controller 14 may be hardwired to the focuser 12 , or preferably employs wireless technology and a wireless receiver 50 .
Wireless controller 14 transmits a signal received by wireless receiver 50 to activate the focuser 12 for each direction of rotation. A radio frequency transmitter and receiver may be employed. The frequency is preferably non-regulated with a maximum range of ten feet. Infrared technology is preferred to reduce the possibility of interference between multiple power focusing devices 10 which may be operated in the same vicinity.
Referring to FIG. 5 wireless controller 14 preferably includes encoder 54 , sender 56 , power source 58 , and two switches 53 . Encoder 54 preferably employs low power, high noise immunity CMOS technology and is capable of encoding information which consists of N address bits and 12-Ndata bits.
Encoder 54 encodes a command signal. Sender 56 sends a signal via RF or preferably infrared radiation. Power source 58 supplies power to encoder 54 and sender 56 . Switches 53 close their respective circuits to initiate encoder 54 encoding a signal.
FIG. 8 schematically depicts a detailed circuit as utilized in one embodiment wherein encoder 54 , sender 56 , power source 58 , and two switches 53 are identified by like reference numerals. As shown in this embodiment, encoder 54 may be a an HT12A or equivalent manufactured by Holtek Semiconductor, Inc. located at No. 3 Creation Road II, Science -based Industrial Park, Hsinchu, Taiwan, R.O.C. This encoder is described in a document entitled HT12A/HT12E 2 12 Series of Encoders published Apr. 11, 2000, which is incorporated herein in its entirety by reference.
A detailed circuit of one embodiment of the invention is schematically depicted in FIGS. 6 and 8. Those skilled in the art may employ other circuits without departing from the spirit and scope of the invention.
Referring to FIG. 7, wireless receiver 50 generally includes receiver 62 , decoder 64 and motor driver 66 and is operably connected to motor 44 . Receiver 62 receives a signal which is decoded by decoder 64 which in turn activates motor driver 66 to control motor 44 . A detailed example circuit of an embodiment is schematically depicted in FIG. 8 wherein components are identified by like reference numerals. Other circuits may be employed without departing from the spirit and scope of the invention.
As depicted in FIG. 8, receiver 62 is preferably a bipolar integrated circuit with photo detection function such as a Panasonic PNA4612M or equivalent as described in a document entitled Photo IC PNA 4611 M Series which is incorporated herein in its entirety by reference. Decoder 64 is preferably a Holtek HT12D integrated circuit as described in a document entitled 2 12 Series of Decoders published Jul. 12, 1999 which is incorporated herein in its entirety by reference. Motor driver 66 is preferably a Holtek HT6751A or equivalent as described in a document entitled HT 6751 A/B Camera Motor Driver (1.5 Channel) published Aug. 7, 2000 which is incorporated herein in its entirety by reference.
As is apparent in FIGS. 1 through 4, the focuser 12 is connected to the focusing ring 26 via pulley 38 and belt 40 . Other approaches, such as friction wheels, gears, and sprocket and chains may be employed without departing from the spirit and scope of the invention.
The power focusing device 10 is depicted in FIGS. 1 through 4 as an attachment to an existing telescopic sight 16 . However, it is specifically contemplated that the power focusing device 10 may be integrated into a telescopic sight as a power focusing telescopic sight unit.
In operation, the focuser 12 is mounted to the telescopic sight 16 via brackets 36 . The controller 14 is mounted on the firearm 18 at a location preferred by the marksman that will use it. The belt 40 is engaged around focusing ring (adjuster) 26 and pulley 38 . The firearm 18 is then sighted as usual through eyepiece 22 . The marksman may activate switch 52 as desired to focus the telescopic sight 16 on the target (not shown) or adjust any other parameter of the sight.
Upon activation of switch 52 in a first direction encoder 54 generates a signal and delivers it to sender 56 . Sender 56 converts the signal to RF or infrared radiation and transmits it. This signal is received by receiver 62 , converted to electrical impulses and sent to decoder 64 . Decoder 64 decodes the signal command and activates motor driver 66 in the desired direction to control motor 44 . Motor 44 then drives reduction gear 46 which in turn adjusts an adjustable parameter of scope 16 such as focuser 12 .
The present invention may be embodied in other specific forms without departing from the spirit of the essential attributes thereof; therefore, the illustrated embodiments should be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention. | A motorized, finger operated mechanism for focusing or otherwise adjusting a telescopic sight. The power focusing device generally includes a battery powered motorized focus mechanism operably attachable to the focusing ring of a telescopic sight, a wireless receiver and a wireless controller. The operator controls the focusing mechanism by manipulation of the controller. The focus mechanism includes a motor, a reduction drive, a power source and a device to engage the focusing ring. The focus mechanism may be secured to an existing telescopic sight or integrated into the telescopic sight design. | 5 |
RELATED APPLICATION
[0001] This application claims priority to Australian Provisional Application No. 2007905189, filed on Sep. 21, 2007, said priority application being fully incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a barbeque grill assembly, a barbeque grill plate and a barbeque kit. The invention has been primarily developed for use with a gas barbeque and will be described hereinafter with reference to this application,
BACKGROUND OF THE INVENTION
[0003] Barbeques with grill plates that are inclined with respect to horizontal are known. Such grill plates generally include a recess or drain at their lower end. During cooking, fats and other fluids released from the food being cooked drain down the surface of the grill plate into the drain. This provides a healthier cooked food. However, such grill plates are unsuitable for cooking many relatively liquid foods, such as eggs or food cooked in a sauce or marinade, as these foods slide down the grill plate towards and into the drain.
[0004] It is an object of the present invention to substantially overcome, or at least ameliorate, the above disadvantage.
OBJECT OF THE INVENTION
[0005] It is the object of the present invention to substantially overcome or at least ameliorate one or more of the above disadvantages.
SUMMARY OF THE INVENTION
[0006] Accordingly, in a first aspect, the present invention provides a barbeque grill assembly comprising:
[0007] a grill plate with a substantially planar first cooking surface having an opening therein; and
[0008] a cooking insert adapted for releasable engagement with the opening and having a substantially planar second cooking surface;
[0009] wherein the first cooking surface and the second cooking surface are non-parallel with respect to each other.
[0010] The first and second surfaces are preferably angled with respect to each other by about 2.5 degrees. The grill plate is preferably installed with the second cooking surface horizontal and the first cooking surface angled away from horizontal by about 2.5 degrees. The grill plate preferably includes a recess at or near one (lower) end, the recess adapted for connection to a drainage arrangement. The grill plate is preferably cast iron.
[0011] The opening is preferably substantially circular and most preferably bounded by a plurality of inwardly directed cooking insert support flanges that are parallel to the second cooking surface.
[0012] In one form, the cooking insert is preferably a cast iron grill tray with a peripheral edge angled outwardly and away from the second cooking surface. The edge preferably includes one or more handles therein.
[0013] In another form, the cooking insert is preferably a ceramic pizza tray. The tray preferably includes one or more handles thereon. In a variation of this form, a cast iron grill tray is positioned in the opening and the ceramic pizza tray is positioned on the cast iron grill tray. In a further variation, a foil tray, preferably disposable, is positioned between the cast iron grill tray and the ceramic pizza tray,
[0014] In yet another form, the cooking insert is preferably a circular stainless steel fluid or wood chip tray with a peripheral edge angled outwardly and away from the second cooking surface. In this form, the barbeque grill assembly further comprises a smoker/roaster rack having an array of rack bars that are parallel to the second cooking surface.
[0015] In a yet further form, the cooking insert is preferably a stainless steel poultry tray with a peripheral edge angled outwardly and away from the second cooking surface and a central poultry support formation.
[0016] In a second aspect, the present invention provides a barbeque grill plate comprising:
[0017] a substantially planar first cooking surface having an opening therein; and
[0018] one or more cooking insert support surfaces substantially adjacent the opening, wherein the cooking surface and the support surfaces are non-parallel with respect to each other.
[0019] The cooking surface and the support surfaces are preferably angled with respect to each other by about 2.5 degrees. The grill plate is preferably installed with support surfaces horizontal and the cooking surface angled from horizontal by about 2.5 degrees. The grill plate preferably includes a recess at or near one end, the recess adapted for connection to a drainage arrangement.
[0020] The opening is preferably substantially circular, and the support surfaces preferably form part of a plurality of inwardly directed support flanges that are inclined with respect to the cooking surface.
[0021] In a third aspect, the present invention provides a barbeque kit comprising:
[0022] a grill plate with a substantially planar first cooking surface having an opening therein; and
[0023] a grill tray, a pizza tray, a fluid/wood chip tray and a poultry tray that are each adapted for releasable engagement with the opening and that each have a substantially planar second cooking surface, wherein the first cooking surface and the second cooking surface are non-parallel with respect to each other.
[0024] The first cooking surface and the second cooking surface are preferably angled with respect to each other at about 2.5 degrees. The grill plate is preferably installed with the second cooking surface horizontal and the first cooking surface angled to horizontal by about 2.5 degrees. The grill plate preferably includes a recess at or near one end, the recess adapted for connection to a drainage arrangement.
[0025] The opening is preferably substantially circular, and most preferably bounded by a plurality of inwardly directed cooking insert support flanges that are parallel to the second cooking surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Preferred embodiments of the present invention will now be described, by way of examples only, with reference to the accompanying drawings wherein:
[0027] FIG. 1 is an exploded perspective view of an embodiment of a grill plate, together with four embodiments of cooking inserts;
[0028] FIG. 2 is a perspective view of the grill plate shown in FIG. 1 ;
[0029] FIG. 3 a is an exploded perspective view of the grill plate of FIG. 1 with the grill tray insert shown in FIG. 1 ;
[0030] FIG. 3 b is an assembled perspective view of the components shown in FIG. 3 a;
[0031] FIG. 4 a is a partial perspective view of the components shown in FIG. 3 b;
[0032] FIG. 4 b is the side view of the components shown in FIG. 4 a;
[0033] FIG. 5 is a perspective view of the grill plate shown in FIG. 1 in use with a wok;
[0034] FIG. 6 a is an exploded perspective view of the grill plate shown in FIG. 1 and the marinating/smoking tray insert shown in FIG. 1 ;
[0035] FIG. 6 b is an assembled perspective view of the components shown in FIG. 6 a with hood removed;
[0036] FIG. 6 c is perspective view of the component showns in FIG. 6 b with the hood closed;
[0037] FIG. 7 a is a partial perspective view of the components shown in FIG. 6 b;
[0038] FIG. 7 b is a side view of the components shown in FIG. 7 a;
[0039] FIG. 8 a is an exploded perspective view of the grill plate shown in FIG. 1 with the poultry tray insert shown in FIG. 1 ;
[0040] FIG. 8 b is an assembled view of the components shown in FIG. 8 a with a chicken positioned thereon;
[0041] FIG. 9 a is an exploded perspective view of the grill plate shown in FIG. 1 with the pizza tray insert shown in FIG. 1 ; and
[0042] FIG. 9 b is an underside perspective view of the pizza tray insert shown in FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0043] FIG. 1 shows a barbeque grill assembly, or kit of components, 10 suitable for use with a barbeque with one or more gas burners (not shown). The assembly 10 comprises a matte vitreous cast iron grill plate 12 , a matte vitreous cast iron grill tray insert 14 , a steel marinating/smoking tray insert 16 , a steel rack 18 , a steel poultry tray insert 20 , a stone pizza tray insert 22 . The barbeque also includes a hood 24 with an insulated handle 24 a and a thermometer 24 b.
[0044] As best shown in FIG. 2 , the grill plate 12 has a substantially rectangular planar first cooking surface 26 , which has a generally circular opening 28 therein. The grill plate 12 also includes a recess 28 , with a drain opening 30 , extending substantially across its front edge. The recess 28 is angled downwardly towards the opening 30 and forms part of a fat/fluid drainage arrangement (not shown). The drainage arrangement is shown in the applicant's Australian Provisional Patent Application entitled: “Improvements in barbeques”, filed 17 Sep. 2007, the contents of which are incorporated herein by cross reference.
[0045] The grill plate 12 also includes a pair of grooves 32 extending adjacent and along the sides of the grill plate 12 , which assist in locating feet 18 a (see FIG. 1 ) of the rack 18 .
[0046] The opening 28 is bounded by three inwardly directed cooking insert support flanges 34 which are separated by arcuate gaps 36 .
[0047] FIGS. 3 a and 3 b show the grill plate 12 with the grill tray insert 14 positioned within the opening 28 . The grill plate 14 includes three arcuate indentations 38 which locate it with respect to the opening 28 . The grill plate 14 also includes three handle portions 40 to assist in adding or removing the grill plate 14 from the grin plate 12 . The central or inner part of the grill plate 12 defines a planar second cooking surface 42 .
[0048] As best shown in FIGS. 5 a and 5 b, the grill plate's first cooking surface 26 is not parallel to the grill trays second cooking surface 42 . More particularly, in use, the second cooking surface 42 is substantially horizontal and the first cooking surface 26 is angled forwardly downwardly at about 2.5 degrees from horizontal.
[0049] The differently angled cooking surfaces 26 and 42 are advantageous as they result in a barbeque grill plate in which the inclined first cooking surface 26 can be used to cook relatively solid foods (e.g. sausages and steaks) and the second horizontal cooking surface 42 can be used to cook relatively liquid foods (e.g. eggs and foods cooked in a sauce or marinade). Fat and other liquids released from the relatively solid foods cooked on the inclined first cooking surface 26 flow downwardly into the recess 28 for removal via the drainage arrangement. This provides a healthier cooked food. Food cooked on the second horizontal cooking surface 42 is prevented from running into the recess 28 and drainage arrangement. The cooking surfaces 26 and 42 can thus be used to cook differing types of food, simultaneously if required, using a single barbeque.
[0050] The upper surfaces of the support flanges 34 are, in use, also horizontal. As a result, and as shown in FIG. 6 , this allows the support flanges 34 to also act as a wok trivet. This allows food to be cooked on the inclined first cooking surface 26 and also within a wok 44 , simultaneously if required.
[0051] FIGS. 6 a to 7 b show the grill plate 12 with the marinating/smoking tray insert 16 positioned within the opening 28 . The marinating/smoking tray insert 16 , and tray 18 , also each have a second horizontal cooking surface 42 . In this configuration, food can be cooked on the smoked (e.g. using woodchips) or steamed on the rack 18 .
[0052] FIGS. 8 a and 8 b show the grill plate 12 with the poultry tray insert 20 positioned F within the opening 28 . The the poultry tray insert 20 also has a second horizontal cooking surface 42 . In this configuration, food can be cooked on the first cooking surface 26 and a chicken 46 , or other form of poultry, can be roasted on the poultry tray insert 20 , simultaneously if required.
[0053] FIGS. 9 a and 9 b show the grill plate 12 with the pizza tray insert 22 positioned within the opening 28 . The pizza tray insert 22 also has a second horizontal cooking surface 42 and a pair of handles 48 for positioning the tray 22 with respect to the opening 28 in the grill tray 12 . A wire ring 50 is attached to the underside of the handles 48 that includes three arcuate portions 50 a which locate the pizza tray insert 22 with respect to the flanges 34 and the gaps 36 surrounding the opening 28 . In this configuration, a pizza can be cooked on the pizza tray insert 22 . In a variation (not shown) of this configuration, the cast iron grill tray 14 is positioned in the opening 28 and the pizza tray 22 is positioned on the cast iron grill tray 14 . In a further variation (not shown), a disposable foil tray (e.g. holding woodchips) is positioned on the cast iron grill tray 14 beneath the ceramic pizza tray 22 .
[0054] The barbeque grill assembly/kit 10 is thus able to easily and quickly accommodate many differing types of foods and/or cooking styles, in some cases simultaneously if required, without requiring multiple barbeques or other cooking devices.
[0055] Although the invention has been described with reference to preferred embodiments, it will be appreciated by those persons skilled in the art, that the invention can be embodied in many other forms. | A barbeque grill assembly ( 10 ) including a grill plate ( 12 ) and a cooking insert ( 14 ). The grill plate ( 12 ) has a substantially planar first cooking surface ( 26 ) with an opening ( 28 ) therein. The cooking insert ( 14 ) is adapted for releasable engagement with the opening ( 28 ) and has a substantially planar second cooking surface ( 42 ). The first cooking surface ( 26 ) and the second cooking surface ( 42 ) are non-parallel with respect to each other. | 0 |
BACKGROUND OF THE INVENTION
Electronic circuits included on circuit boards often have thickened metallized areas serving as terminal pads which allow electrical devices to be wire bonded thereto. Conventional methods for forming such circuits usually involve forming a photoresist pattern on a copper clad circuit board substrate and electro-plating a thick patterned layer of copper over the copper cladding. Areas of copper are etched away to produce a desired circuit pattern on the circuit board substrate. The thickened areas of the circuit are suitable for wire bonding to electronic devices.
A drawback with such a method is that etching the unneeded areas of copper from the circuit board substrate usually requires a relatively long etching process due to the thickened layers of metal. As a result, the side edges of the circuit pattern often become undercut and/or ragged which can affect the performance of the circuit. In addition, temporary bussing pathways may be formed to provide electrical continuity between different portions of the circuit board substrate or between opposite sides thereof. The electrical continuity is required for providing electrical current to areas where the deposition of metallic material by electro-plating or electrolytic deposition is desired. The temporary bussing pathways are later etched away in another etching process. The added etching process may affect the quality of the side edges of the remaining portions of the circuit pattern.
SUMMARY OF THE INVENTION
The present invention provides a method of forming a circuit on a circuit board including thickened areas suitable for wire bonding to electrical devices where the traces of the circuit have limited undercutting and can be manufactured with higher tolerances than possible with previous methods. The method includes forming a metallic circuit pattern on a base substrate. The circuit pattern has traces which are connected together by temporary bussing. A resist pattern is formed over the circuit pattern for defining at least one terminal pad. A layer of metal is formed on at least one area of the circuit pattern exposed by the resist pattern to a thickness suitable for serving as the at least one terminal pad for the circuit. A portion of the base substrate at the location of the temporary bussing is removed, thereby causing the removal of the temporary bussing.
In preferred embodiments, the metallic circuit pattern is formed by forming a first resist pattern for defining the circuit pattern over a metallic layer on the base substrate. Areas of the metallic layer on the base substrate exposed by the first resist pattern are etched away thereby forming the metallic circuit pattern under the first resist pattern. The first resist pattern is then stripped from the base substrate to uncover the circuit pattern. The circuit pattern and its side edges are covered with a protective metallic layer. The protective metallic layer is formed by forming a metallic inner barrier layer over the circuit pattern and side edges thereof by electroless deposition and then forming a metallic outer layer over the barrier layer also by electroless deposition.
The base substrate preferably has opposing sides each with a metallic layer thereon. In such a case, before forming the metallic circuit pattern, at least one via hole is formed through the base substrate. A conductive pathway is formed through the at least one via hole to provide electrical continuity between the metallic layers on the opposing sides of the base substrate. The conductive pathway later becomes part of the temporary bussing when the circuit pattern is formed. The conductive pathway may be formed by first forming a thin metallic layer within the at least one via hole and over the metallic layers of the base substrate by electroless deposition, and then forming a thick metallic layer over the thin layer as well as within the at least one via hole by electrolytic deposition. The metallic layer which forms the at least one terminal pad is deposited by electrolytic deposition.
In one embodiment, the metallic layers of the base substrate which are on opposing sides of the base substrate are made of copper. The conductive pathway is formed by first forming a thin copper layer within the at least one via hole and over the copper layers of the base substrate by electroless copper deposition, and then forming a thick copper layer over the thin layer by electrolytic copper deposition. Consequently, after etching, the resulting metallic circuit pattern is made of copper. The protective metallic layer is formed by forming an inner barrier layer of nickel over the circuit pattern and side edges thereof by electroless nickel deposition and then forming an outer layer of gold over the inner barrier layer of nickel by electroless gold deposition. The terminal pads are formed by electrolytic gold deposition. Finally, the temporary bussing is routed out with a router.
In another embodiment, the metallic circuit pattern is formed by providing the base substrate with a metallic layer thereon. A first resist pattern is formed over the metallic layer on the base substrate for defining the circuit pattern. Next, the thickness of the metallic layer is increased in areas of the base substrate exposed by the first resist pattern. The thickened metallic layer in the areas exposed by the first resist pattern is later covered with a protective metallic layer. The first resist pattern is then stripped from the base substrate. Finally, areas of the base substrate not protected by the protective metallic layer are etched from the base substrate, thereby forming the metallic circuit pattern.
In the present invention, since the circuit pattern is etched before the thick layer of metal forming the terminal pads is deposited, the etching is performed on a relatively thin layer of metal for a relatively short period of time. As a result, the side edges of the traces of the circuit pattern once formed, are not subjected to a lengthy attack by the etchant and experience very little etching and/or undercutting. In addition, by removing the temporary bussing by routing, the circuit pattern is not subjected to any further etching steps, thereby preserving the quality of the side edges of the traces. Consequently, the present invention is suitable for forming very fine and delicate traces with high yield as well as with high performance.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
FIG. 1 is a flow chart depicting the steps of one method for fabricating electronic circuits in accordance with the present invention.
FIG. 2 is a side sectional view of a portion of a circuit board substrate having a via hole depicting deposited metallized layers.
FIG. 3 is a side sectional view of a portion of the circuit board substrate depicting a first pattern of photoresist formed over the metallized layers.
FIG. 4 is a side sectional view of the portion of the circuit board substrate of FIG. 3 depicting metallized areas surrounding the first photoresist pattern removed by etching to form a metallized circuit pattern.
FIG. 5 is a plan view of a portion of the circuit board substrate having a metallized circuit pattern defined thereon, including temporary bussing pathways.
FIG. 6 is a side sectional view of the portion of the circuit board substrate of FIG. 3 depicting protective metallic layers covering the circuit pattern.
FIG. 7 is a plan view of the portion of the circuit board substrate of FIG. 5 depicting a second pattern of photoresist and terminal pads formed thereon.
FIG. 8 is a plan view of the portion of the portion of the circuit board substrate of FIG. 7 with the second pattern of photoresist removed to show the circuit pattern with the terminal pads.
FIG. 9 is a side sectional a view of the portion of the circuit board substrate of FIG. 6 depicting a terminal pad formed thereon.
FIG. 10 is a plan view of the portion of the circuit board substrate of FIG. 8 with the temporary bussing pathways routed out.
FIG. 11 is a flow chart depicting the steps of another method for fabricating electronic circuits.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 depicts the steps of one method for forming a circuit in accordance with the present invention. In step 10 , a conventional circuit board substrate 36 (FIG. 2) having thin metallic base layers 36 a covering opposing sides is provided. Typically, the metallic layers 36 a are formed of copper. The metallic layers 36 a are cleaned in a cleaning process in preparation for subsequent processes. In step 12 , a series of via holes 38 are formed through substrate 36 and metallic layers 36 a (FIGS. 2 and 5) at predetermined locations. The via holes 38 are preferably drilled, but alternatively, may be punched, stamped or formed by a laser. Typically, the via holes 38 are positioned on substrate 36 adjacent to a location where an opening in substrate 36 will be later located. The position of the via holes 38 is also at the future location of temporary bussing 42 (FIG. 5 ). The temporary bussing 42 is later removed and an electrical device positioned at the same location. Typically two via holes 38 are formed at the future location of temporary bussing 42 , but alternatively, the number of via holes 38 may vary depending upon the situation at hand.
In step 14 (FIG. 1 ), a thin metallic layer of copper 37 is deposited over the metallic layers 36 a of substrate 36 as well as over the inner surfaces of via holes 38 (FIG. 2 ). The thin layer of copper 37 is typically formed in a bath by electroless copper deposition. The portion of layer 37 extending through the via holes 38 provides electrical continuity between the two separated layers of copper 36 a . Although layer 37 is preferably formed by electroless deposition, alternatively, layer 37 may be formed by other suitable methods such as vapor deposition.
Typically, layer 37 is too thin to survive subsequent processing steps. As a result, in step 16 (FIG. 1 ), a thicker metallic layer of copper 39 (FIG. 2) is deposited over the thin layer 37 by electrolytic copper deposition in a electrolyte bath where the copper surfaces are electrically connected to a power source and current passed therethrough. Electrical continuity to the copper surfaces on both sides of substrate 36 is provided by the thin layer of copper 37 within the via holes 38 which permits the electrolytic deposition of copper on both sides of substrate 36 as well as within the via holes 38 . Electrolytic deposition is able to deposit a thicker layer of copper 39 than the layer 37 formed by electroless deposition. The copper layer 39 within the via holes 38 has a thickness that is sufficient to survive subsequent processes and thus maintain electrical continuity to both sides of substrate 36 .
In Step 18 (FIG. 1 ), a first photoresist layer 61 (FIG. 3) is deposited over one or both of the copper layers 39 as desired. Patterns of desired circuits are formed from the photoresist by conventional exposure and development processes. The patterns provide masks for forming the desired circuits. Such circuit patterns may be formed on one or both sides of substrate 36 depending upon the application at hand. FIG. 3 depicts a portion of a pattern 41 of photoresist formed on layer 39 .
In step 20 (FIG. 1 ), the copper material which is not covered by the photoresist pattern 41 is etched away in an etching bath to form a copper circuit pattern 40 consisting of layers 36 a , 37 and 39 (FIG. 4 ). The side edges 47 of circuit pattern 40 have the added thicknesses of layers 36 a , 37 and 39 . The photoresist pattern 41 is then stripped away in step 22 with an appropriate solution in a stripping bath. In the example depicted in FIG. 5, the circuit pattern 40 includes a first radio frequency trace 44 , a second radio frequency trace 46 , a first DC trace 48 , a second DC trace 50 and temporary bussing 42 connected therebetween. The traces 44 and 46 are on opposite sides of temporary bussing 42 , while traces 48 and 50 are side by side between traces 44 / 46 . In the example shown, traces 48 and 50 are relatively narrow in comparison to traces 44 and 46 . As a result, traces 48 and 50 include widened regions 49 over which terminal pads will later be formed for bonding to an electrical device. FIG. 4 depicts a cross sectional view of the portion of circuit pattern 40 forming trace 44 . The temporary bussing 42 extends around and includes the two metallized via holes 38 , a central rectangular region 42 a and a series of narrow traces 42 b extending from rectangular region 42 a to traces 44 , 46 , 48 and 50 . The temporary bussing 42 provides electrical continuity between the traces 44 , 46 , 48 and 50 of circuit pattern 40 . In addition, temporary bussing 42 provides electrical continuity between circuit pattern 40 and any circuit patterns or metallic areas located on the opposite side of substrate 36 . Although not shown in FIG. 5, temporary bussing 42 may be employed to provide electrical continuity to circuit patterns adjacent to circuit pattern 40 on the same side of substrate 36 . In such a case, another trace would extend therebetween. It is understood that circuit pattern 40 may be of other suitable configurations depending upon the application at hand. It is also understood that other circuit patterns may be formed on the same and/or opposite side of substrate 36 .
In step 24 (FIG. 1 ), a thin layer of nickel 43 (FIG. 6) is deposited over the circuit pattern 40 in a bath by electroless nickel deposition. The layer of nickel 43 covers the top surfaces as well as the side edges 47 of circuit pattern 40 . Next, in step 26 , a thin layer of gold 45 is deposited over the layer of nickel 43 by electroless gold deposition and also covers the top surfaces and side edges 47 . The layers of nickel 43 and gold 45 are deposited only over circuit pattern 40 and not over non-metallic areas of substrate 36 . The combined layers of nickel 43 and gold 45 serve as a protective metallic layer or jacket for protecting the top surfaces and side edges 47 of circuit pattern 40 which prevents or reduces etching as well as undercutting during subsequent processing steps. The layer of nickel 43 acts as a barrier layer between the copper and the gold layers to prevent migration between the copper and the gold layers.
In step 28 (FIG. 1 ), a second layer of photoresist 56 (FIG. 7) is deposited upon substrate 36 and over circuit pattern 40 . The second layer of photoresist 56 is exposed and developed by conventional methods for forming a pattern 58 of open areas 59 . The areas 59 correspond to desired locations for forming terminal pads for circuit pattern 40 . In step 30 , a layer of gold 54 is deposited by electrolytic gold deposition in an electrolytic bath over portions of circuit pattern 40 exposed by the open areas 59 of the photoresist pattern 58 . The electrolytic layer of gold 54 is positioned on the appropriate areas of circuit pattern 40 to form terminal pads 44 a , 46 a , 48 a and 50 a for respective traces 44 , 46 , 48 and 50 . Layer 54 is formed to a thickness suitable for bonding to electrical devices. The temporary bussing 42 including via holes 38 , provide the necessary electrical continuity within circuit pattern 40 and to other circuit patterns or metallized areas if any, including those on the opposite side of circuit board substrate 36 for the electrolytic gold deposition.
In step 32 (FIG. 1 ), the second layer of photoresist 56 is then removed in a bath to expose the circuit pattern 40 and thickened terminal pads 44 a , 46 a , 48 a , and 50 a (FIGS. 8 and 9 ). Terminal pads 44 a and 46 a are positioned at the ends of respective traces 44 and 46 adjacent to traces 42 b . Terminal pads 48 a and 50 a are positioned over widened regions 49 at the ends of respective traces 48 and 50 adjacent to traces 42 b . Finally, in Step 34 , an opening 52 is routed out from substrate 36 near and between terminal pads 44 a , 46 a , 48 a , and 50 a (FIG. 10 ). The opening 52 removes the temporary bussing 42 including via holes 38 , rectangular region 42 a and traces 42 b without employing an etching step. As a result, there are no subsequent process steps to affect the quality and definition of the side edges of circuit pattern 40 . The opening 52 allows an electrical device to be positioned therein and the thickened terminal pads 44 a , 46 a , 48 a and 50 a allow the electrical device to be wire bonded thereto. Depending upon the application at hand, opening 52 may be a hole that extends completely through substrate 36 or may be merely a recess or pocket having a depth that is less than the thickness of substrate 36 .
Since the circuit pattern in the present invention is etched from a relatively thin layer of metal, the etching time is relatively short and fine or delicate trace definition can be achieved without significant lateral etching and/or undercutting of the side edges. Longer etching times tend to allow the etchant to attack the side edges of the circuit traces resulting in ragged or undercut side edges which can affect the quality and performance of the circuit. This is important especially when forming circuits with delicate traces. The protective metallic layer further insures that the definition of the traces is not affected by subsequent process steps. Forming the terminal pads on the circuit pattern only at the locations required is both cost and time effective in comparison to prior art processes where large areas are first thickened and then later require etching. Finally, routing out the temporary bussing mechanically removes the temporary bussing and eliminates another etching step. This is desirable because additional etching steps after the formation of the circuit pattern can affect the quality of the edges of the traces. Circuits made in accordance with the present invention not only are high precision and high quality, but also can be manufactured with higher tolerances and with higher yields than by prior art methods.
In one embodiment, circuit board substrate 36 (FIG. 2) is preferably made of low loss, low dielectrical circuit board material, but alternatively, may be fiberglass, teflon or multifunctional epoxy, etc. Substrate 36 is preferably about 0.003 to 0.070 inches thick, but alternatively, may be less than 0.003 inches or greater than 0.070 inches. The base layers 36 a of copper are preferably about 350 to 700 micro-inches (0.00035 to 0.0007 inches) thick. Layers 36 a are preferably formed from foil that is rolled onto the underlying board material, but alternatively, may be formed by electrolytic deposition. Although two layers 36 a are preferred, there may be instances where one layer 36 a is desired.
The via holes 38 are preferably 13 to 20 mils in diameter. In some applications, some via holes 38 may be kept in the final circuit board configuration if desired. Although metallized via holes 38 are preferred for providing electrical continuity, alternatively, conductive pathways may be provided by mechanically inserting a series of conductive members through the substrate 36 which are in contact with layers 36 a . In such a case, removal of the conductive members may be by routing or pushing the conductive members from the base substrate 36 .
The thin layer of copper 37 formed by electroless copper deposition in step 14 is typically about 50 microinches thick. The thicker layer of copper 39 formed by electrolytic copper deposition in step 16 is typically about 100-150 microinches thick but may be greater. Although Steps 14 and 16 (FIG. 1) are preferred for depositing layers 37 and 39 over layers 36 a , alternatively, Steps 14 and 16 can be replaced by a direct plating step which is an electroless process capable of depositing a thicker metallic layer than is possible with Step 14 . The layers of nickel 43 and gold 45 forming the protective metallic layer (steps 24 and 26 ) are each about 50 to 150 microinches thick. The layer of gold 54 formed by electrolytic gold deposition in step 30 to provide the terminal pads 44 a , 46 a , 48 a and 50 a is about 80 to 100 microinches thick.
Although layers 36 a , 37 and 39 are preferably copper, layers 36 a , 37 and 39 may be formed of other suitable materials such as aluminum, silver or gold. In addition, although nickel is preferred as the first layer 43 of the protective metallic layer on the circuit pattern 40 (FIG. 6 ), other suitable metals may be employed such as palladium, silver or tin. In such cases, the materials forming layers 36 a , 37 , 39 , 43 , 45 and 54 are appropriately selected for compatibility. Finally, depending upon the materials chosen, the protective metallic layer may be formed from a single layer of material instead of an inner barrier layer and an outer layer.
FIG. 11 depicts another method for forming a circuit in accordance with the present invention. Generally, instead of plating a whole panel as performed in Step 16 of FIG. 1, the method depicted in FIG. 11 plates a desired pattern defined by photoresist. Consequently, some of the process steps in FIG. 11 are performed in a different order than in FIG. 1 . For example, in FIG. 11, after depositing a thin layer of electroless copper in Step 14 , a first photoresist layer is deposited, exposed and developed in Step 18 . Then in Step 16 , a thick layer of copper is deposited by electrolytic copper deposition in a desired pattern defined by the photoresist. The thickened patterned layer of copper is in the configuration of the desired circuit pattern. Next, in Step 25 , a layer of metal (or metals) compatible with gold is deposited over the metallic pattern for providing a protective metallic layer similar to that provided in FIG. 1 by Steps 24 and 26 . This protective layer typically covers only the top surface. The first photoresist layer is stripped in Step 22 and the exposed copper is etched in Step 20 to form the circuit pattern. The second layer of photoresist may then be deposited, exposed, and developed in Step 28 in preparation for the formation of terminal pads as in FIG. 1 .
While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
For example, although a particular circuit pattern 40 has been depicted in the figures, it is understood that any circuit pattern may be formed and that there may be multiple circuit patterns on one or both sides of circuit board substrate 36 . In addition, although via holes 38 are depicted in the figures and described above, the via holes 38 may be omitted in certain instances. In such cases, steps 14 and 16 of FIG. 1 may be omitted or altered to suit the situation at hand. It is understood that the configuration and locations of the temporary bussing 42 may vary between circuits. Although the temporary bussing 42 including the via holes 38 is preferably removed by routing, alternatively, such areas maybe removed by drilling, punching, another etching step or laser ablation. Furthermore, although specific dimensions have been provided for circuit pattern 40 , such dimensions may vary depending upon the situation at hand. Finally, various features of the fabrication methods depicted in the figures and described above may be omitted, substituted or combined, depending upon the situation at hand. | A method of forming a circuit includes forming a metallic circuit pattern on a base substrate. The circuit pattern has traces which are connected together by temporary bussing. A resist pattern for defining at least one terminal pad is formed over the circuit pattern. A layer of metal is formed on at least one area of the circuit pattern exposed by the resist pattern to a thickness suitable for serving as the at least one terminal pad for the circuit. A portion of the base substrate at the location of the temporary bussing is removed thereby causing the removal of the temporary bussing. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to erasers and more particularly pertains to an eraser holder fixedly securable to the end of a writing instrument such as a pencil.
2. Description of the Prior Art
As is well known in the prior art, a pencil usually provides means for both writing and erasing. More particularly, a wooden pencil usually includes an eraser at one end thereof, and the eraser is contained within a band designed to support its engagement with the pencil. As the eraser wears down however, the band support serves little purpose and eventually, the band prevents access to an additional eraser portion after the eraser has been worn down to a top edge of the band. Unfortunately, no means have been developed to remove the unnecessary portion of the band so as to access additional sections of an eraser contained therein. If such a band could be removed when not needed, possibly in small increments, the possibility of accessing the remaining portion of a pencil eraser could be realized. As such, there appears to be a continuing need for an improved eraser band configuration that would enable a person to use more of the eraser once it has been worn down to the band. In this respect, the present invention substantially addresses this problem.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of eraser holders now present in the prior art, the present invention provides a new eraser holder wherein the same can be utilized to allow ongoing access to an eraser contained therein, while at the same time operating to support a much larger eraser on a pencil. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide an eraser holder and method which has many of the advantages of the eraser holders mentioned heretofore and many additional novel features that result in an eraser holder which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art eraser holders, either alone or in any combination thereof.
To attain this, the present invention generally comprises an improved eraser holder on a pencil includes an eraser support band which can be removed in incremental sections to provide access to additional portions of the eraser after the original exposed portion has been worn down. Fracture lines on the band facilitate incremental removal of the sections, and the fracture lines are axially misaligned to strengthen the holder.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new eraser holder and method which has many of the advantages of the eraser holders mentioned heretofore and many novel features that result in an eraser holder which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art eraser holders, either alone or in any combination thereof.
It is another object of the present invention to provide a new eraser holder which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new eraser holder which is of a durable and reliable construction.
An even further object of the present invention is to provide a new eraser holder which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such eraser holder economically available to the buying public.
Still yet another object of the present invention is to provide a new eraser holder which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
Still another object of the present invention is to provide a new and improved eraser holder which facilitates the use of removable sections which progressively expose additional portions of an eraser retained therein.
Yet another object of the present invention is to provide a new and improved eraser holder which allows the use of a much larger eraser on a pencil while also providing access to the complete eraser in a progressive manner.
These together with other objects of the invention, along with 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 the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is a perspective view of a pencil having the improved eraser holder comprising the present invention attached thereto.
FIG. 2 is an enlarged perspective view of the eraser holder comprising the present invention.
FIG. 3 is a perspective view of the eraser holder illustrating the depletion of an exposed portion of eraser.
FIG. 4 is a perspective view illustrating the manner of use of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
With reference now to the drawings, and in particular to FIGS. 1 and 2 thereof, a new eraser holder embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
More specifically, it will be noted that the eraser holder 10 essentially includes a tubular eraser holder 12 of a metallic construction with an elongated cylindrically-shaped eraser 14 contained therein. The eraser holder 12 includes a bottommost clamping band 16 which facilitates its attachment to a conventional wooden pencil 18 in a well known manner, and the eraser 14 initially extends out of the eraser holder 12 by a predetermined amount which will facilitate its selective use as desired.
The elongated tubular eraser holder 12 is provided with a plurality of circumferentially extending scores or fracture lines, each of which is generally designated by the reference numeral 20. These scores 20 are aligned and spaced apart by a predetermined amount. Additionally, each score extends completely around a peripheral surface of the holder 12 and effectively constitutes a weakened area which will allow a fracturing to occur by minimal manual pressure.
The eraser holder 12 further includes a plurality of axially aligned scores, each of which is generally designated by the reference numeral 22, and no two of which lie on the same axial line. Each axial score 22 extends between a juxtaposed set of scores 20, and they similarly represent lines of selective fracture associated with the eraser holder 12. Inasmuch as all of the scores 20, 22 represent weakened areas to facilitate selective fracture of the eraser holder 12, by misaligning the scores 22 in the illustrated manner, additional strength is imparted to the holder 12 whereby an increased length of eraser 14 can be utilized in the holder.
FIGS. 3 and 4 of the drawings illustrate both the novelty and utility of the eraser holder 10 which comprises the present invention. In this respect, FIG. 3 illustrates how the eraser 14 will eventually be worn down so as to be in a close abutting relationship with a top edge 24 of the holder 12. This is the situation that is typically encountered with conventional pencils 18, i.e., once the eraser 14 reaches the top edge 24 of a holder 12, the rest of the eraser contained within the holder is no longer accessible or usable.
FIG. 4 illustrates how the score lines 20, 22 facilitate access to additional portions of the eraser 14 once it has been worn down to a top edge 24. In this respect, a user can insert his fingernail between the top edge 24 of the holder 12 and the eraser 14, and in the vicinity of the topmost axial score 22. With minimal finger pressure then, the score 22 will fracture, and a topmost strip 26 of the holder 12 can be peeled off in the illustrated manner. The removal of the top strip 26 is accomplished by the subsequent fracturing of the first circumferential score 20 and as shown, an additional portion of the eraser 14 is thus exposed for use. Once this additional portion of the eraser 14 is worn down to a new top edge 24, an additional strip 26 of holder 12 can be peeled off to reveal even more of the eraser. Accordingly, depending upon the number of circumferential scores 20, virtually all of an eraser 14 within a holder 12 can be accessed, thereby to eliminate the normal wastage of erasers concealed within holders on conventional pencils 18.
As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | An improved eraser holder on a pencil includes an eraser support band which can be removed in incremental sections to provide access to additional portions of the eraser after the original exposed portion has been worn down. Fracture lines on the band facilitate incremental removal of the sections, and the fracture lines are axially misaligned to strengthen the holder. | 1 |
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 13/482,958, which was filed on May 29, 2012, which is a continuation of U.S. application Ser. No. 12/569,826, which was filed on Sep. 29, 2009, now U.S. Pat. No. 8,186,850, which is a continuation of U.S. application Ser. No. 11/842,145, which was filed on Aug. 21, 2007, now U.S. Pat. No. 7,594,740, which is a continuation of U.S. application Ser. No. 11/542,072, which was filed on Oct. 3, 2006, now U.S. Pat. No. 7,306,353, which is a continuation of U.S. application Ser. No. 10/789,357, which was filed on Feb. 27, 2004, now U.S. Pat. No. 7,114,831, which is a continuation of U.S. application Ser. No. 09/693,548, which was filed on Oct. 19, 2000, now U.S. Pat. No. 6,712,486, which claims the benefit of U.S. Provisional Patent Application Nos. 60/160,480, which was filed on Oct. 19, 1999 and 60/200,531, which was filed on Apr. 27, 2000. The entirety of each of these related applications is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention is in the field of light emitting diode (LED) lighting devices and more particularly in the field of an LED lighting module having heat transfer properties that improve the efficiency and performance of LEDs.
[0004] 2. Description of the Related Art
[0005] Light emitting diodes (LEDs) are currently used for a variety of applications. The compactness, efficiency and long life of LEDs is particularly desirable and makes LEDs well suited for many applications. However, a limitation of LEDs is that they typically cannot maintain a long-term brightness that is acceptable for middle to large-scale illumination applications. Instead, more traditional incandescent or gas-filled light bulbs are often used.
[0006] An increase of the electrical current supplied to an LED generally increases the brightness of the light emitted by the LED. However, increased current also increases the junction temperature of the LED. Increased juncture temperature may reduce the efficiency and the lifetime of the LED. For example, it has been noted that for every 10° C. increase in temperature, silicone and gallium arsenide lifetime drops by a factor of 2.5-3. LEDs are often constructed of semiconductor materials that share many similar properties with silicone and gallium arsenide.
SUMMARY OF THE INVENTION
[0007] Accordingly, there is a need in the art for an LED lighting apparatus having heat removal properties that allow an LED on the apparatus to operate at relatively high current levels without increasing the juncture temperature of the LED beyond desired levels.
[0008] In accordance with an aspect of the present invention, an LED module is provided for mounting on a heat conducting surface that is substantially larger than the module. The module comprises a plurality of LED packages and a circuit board. Each LED package has an LED and at least one lead. The circuit board comprises a thin dielectric sheet and a plurality of electrically-conductive contacts on a first side of the dielectric sheet. Each of the contacts is configured to mount a lead of an LED package such that the LEDs are connected in series. A heat conductive plate is disposed on a second side of the dielectric sheet. The plate has a first side which is in thermal communication with the contacts through the dielectric sheet. The first side of the plate has a surface area substantially larger than a contact area between the contacts and the dielectric sheet. The plate has a second side adapted to provide thermal contact with the heat conducting surface. In this manner, heat is transferred from the module to the heat conducting surface.
[0009] In accordance with another aspect of the present invention, a modular lighting apparatus is provided for conducting heat away from a light source of the apparatus. The apparatus comprises a plurality of LEDs and a circuit board. The circuit board has a main body and a plurality of electrically conductive contacts. Each of the LEDs electrically communicates with at least one of the contacts in a manner so that the LEDs are configured in a series array. Each of the LEDs electrically communicates with corresponding contacts at an attachment area defined on each contact. An overall surface of the contact is substantially larger than the attachment area. The plurality of contacts are arranged adjacent a first side of the main body and are in thermal communication with the first side of the main body. The main body electrically insulates the plurality of contacts relative to one another.
[0010] For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention have been described herein above. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.
[0011] All of these embodiments are intended to be within the scope of the invention herein disclosed. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a perspective view of an LED module having features in accordance with the present invention.
[0013] FIG. 2 is a schematic side view of a typical pre-packaged LED lamp.
[0014] FIG. 3 is a top plan view of the LED module of FIG. 1 .
[0015] FIG. 4 is a side plan view of the apparatus of FIG. 3 .
[0016] FIG. 5 is a close-up side view of the apparatus of FIG. 3 mounted on a heat conductive member.
[0017] FIG. 6 is another sectional side view of the apparatus of FIG. 3 mounted onto a heat conductive flat surface.
[0018] FIG. 7 is a side plan view of an LED module having features in accordance with another embodiment of the present invention.
[0019] FIG. 8 is a side plan view of another LED module having features in accordance with yet another embodiment of the present invention.
[0020] FIG. 9 is a perspective view of an illumination apparatus having features in accordance with the present invention.
[0021] FIG. 10 is a side view of the apparatus of FIG. 9 .
[0022] FIG. 11 is a bottom view of the apparatus of FIG. 9 .
[0023] FIG. 12 is a top view of the apparatus of FIG. 9 .
[0024] FIG. 13 is a schematic view of the apparatus of FIG. 9 mounted on a theater seat row end.
[0025] FIG. 14 is a side view of the apparatus of FIG. 13 showing the mounting orientation.
[0026] FIG. 15 is a side view of a mounting barb.
[0027] FIG. 16 is a front plan view of the illumination apparatus of FIG. 9 .
[0028] FIG. 17 is a cutaway side plan view of the apparatus of FIG. 20 .
[0029] FIG. 18 is a schematic plan view of a heat sink base plate.
[0030] FIG. 19 is a close-up side sectional view of an LED module mounted on a mount tab of a base plate.
[0031] FIG. 20 is a plan view of a lens for use with the apparatus of FIG. 9 .
[0032] FIG. 21 is a perspective view of a channel illumination apparatus incorporating LED modules having features in accordance with the present invention.
[0033] FIG. 22 is a close-up side view of an LED module mounted on a mount tab.
[0034] FIG. 23 is a partial view of a wall of the apparatus of FIG. 21 , taken along line 23 - 23 .
[0035] FIG. 24 is a top view of an LED module mounted to a wall of the apparatus of FIG. 21 .
[0036] FIG. 25 is a top view of an alternative embodiment of an LED module mounted to a wall of the apparatus of FIG. 21 .
[0037] FIG. 26A is a side view of an alternative embodiment of a lighting module being mounted onto a channel illumination apparatus wall member.
[0038] FIG. 26B shows the apparatus of the arrangement of FIG. 26A with the lighting module installed.
[0039] FIG. 26C shows the arrangement of FIG. 26B with a lens installed on the wall member.
[0040] FIG. 26D shows a side view of an alternative embodiment of a lighting module installed on a channel illumination apparatus wall member.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0041] With reference first to FIG. 1 , an embodiment of a light-emitting diode (LED) lighting module 30 is disclosed. In the illustrated embodiment, the LED module 30 includes five pre-packaged LEDs 32 arranged on one side of the module 30 . It is to be understood, however, that LED modules having features in accordance with the present invention can be constructed having any number of LEDs 32 mounted in any desired configuration.
[0042] With next reference to FIG. 2 , a typical pre-packaged LED 32 includes a diode chip 34 encased within a resin body 36 . The body 36 typically has a focusing lens portion 38 . A negative lead 40 connects to an anode side 42 of the diode chip 34 and a positive lead 44 connects to a cathode side 46 of the diode chip 34 . The positive lead 44 preferably includes a reflector portion 48 to help direct light from the diode 34 to the lens portion 38 .
[0043] With next reference to FIGS. 1-5 , the LED module 30 preferably comprises the five pre-packaged LED lamps 32 mounted in a linear array on a circuit board 50 and electrically connected in series. The illustrated embodiment employs pre-packaged aluminum indium gallium phosphide (AlInGaP) LED lamps 32 such as model HLMT-PL00, which is available from. Hewlett Packard. In the illustrated embodiment, each of the pre-packaged LEDs is substantially identical so that they emit the same color of light. It is to be understood, however, that nonidentical LEDs may be used to achieve certain desired lighting effects.
[0044] The illustrated circuit board 50 preferably is about 0.05 inches thick, 1 inch long and 0.5 inch wide. It includes three layers: a copper contact layer 52 , an epoxy dielectric layer 54 and an aluminum main body layer 56 . The copper contact layer 52 is made up of a series of six elongate and generally parallel flat copper plates 60 that are adapted to attach to the leads 40 , 44 of the LEDs 32 . Each of the copper contacts 60 is electrically insulated from the other copper contacts 60 by the dielectric layer 54 . Preferably, the copper contacts 60 are substantially coplanar.
[0045] The pre-packaged LEDs 32 are attached to one side of the circuit board 50 , with the body portion 36 of each LED generally abutting a side of the circuit board 50 . The LED lens portion 38 is thus pointed outwardly so as to direct light in a direction substantially coplanar with the circuit board 50 . The LED leads 40 , 44 are soldered onto the contacts 60 in order to create a series array of LEDs. Excess material from the leads of the individual pre-packaged LED lamps may be removed, if desired. Each of the contacts 60 , except for the first and last contact 62 , 64 , have both a negative lead 40 and a positive lead 44 attached thereto. One of the first and last contacts 62 , 64 has only a negative lead 40 attached thereto; the other has only a positive lead 44 attached thereto.
[0046] A bonding area of the contacts accommodates the leads 40 , 44 , which are preferably bonded to the contact 60 with solder 68 ; however, each contact 60 preferably has a surface area much larger than is required for adequate bonding in the bonding area 66 . The enlarged contact surface area allows each contact 60 to operate as a heat sink, efficiently absorbing heat from the LED leads 40 , 44 . To maximize this role, the contacts 60 are shaped to be as large as possible while still fitting upon the circuit board 50 .
[0047] The dielectric layer 54 preferably has strong electrical insulation properties but also relatively high heat conductance properties. In the illustrated embodiment, the layer 54 is preferably as thin as practicable. For example in the illustrated embodiment, the dielectric layer 54 comprises a layer of Thermagon® epoxy about 0.002 inches thick.
[0048] It is to be understood that various materials and thicknesses can be used for the dielectric layer 54 . Generally, the lower the thermal conductivity of the material used for the dielectric layer, the thinner that dielectric layer should be in order to maximize heat transfer properties of the module. For example, in the illustrated embodiment, the layer of epoxy is very thin. Certain ceramic materials, such as beryllium oxide and aluminum nitride, are electrically non-conductive but highly thermally conductive. When the dielectric layer is constructed of such materials, it is not as crucial for the dielectric layer to be so very thin, because of the high thermal conductivity of the material.
[0049] In the illustrated embodiment, the main body 56 makes up the bulk of the thickness of the circuit board 50 and preferably comprises a flat aluminum plate. As with each of the individual contacts 60 , the main body 56 functions as a heat conduit, absorbing heat from the contacts 60 through the dielectric layer 54 to conduct heat away from the LEDs 32 . However, rather than just absorbing heat from a single LED 32 , the main body 56 acts as a common heat conduit, absorbing heat from all of the contacts 60 . As such, in the illustrated embodiment, the surface area of the main body 56 is about the same as the combined surface area of all of the individual contacts 60 . The main body 56 can be significantly larger than shown in the illustrated embodiment, but its relatively compact shape is preferable in order to increase versatility when mounting the light module 30 . Additionally, the main body 56 is relatively rigid and provides structural support for the lighting module 30 .
[0050] In the illustrated embodiment, aluminum has been chosen for its high thermal conductance properties and ease of manufacture. It is to be understood, however, that any material having advantageous thermal conductance properties, such as having thermal conductivity greater than about 100 watts per meter per Kelvin (W/m-K), would be acceptable.
[0051] A pair of holes 70 are preferably formed through the circuit board 50 and are adapted to accommodate a pair of aluminum pop rivets 72 . The pop rivets 72 hold the circuit board 50 securely onto a heat conductive mount member 76 . The mount member 76 functions as or communicates with a heat sink. Thus, heat from the LEDs 32 is conducted with relatively little resistance through the module 30 to the attached heat sink 76 so that the junction temperature of the diode chip 34 within the LED 32 does not exceed a maximum desired level.
[0052] With reference again to FIGS. 3 and 5 , a power supply wire 78 is attached across the first and last contacts 62 , 64 of the circuit board 50 so that electrical current is provided to the series-connected LEDs 32 . The power supply is preferably a 12-volt system and may be AC, DC or any other suitable power supply. A 12-volt AC system may be fully rectified.
[0053] The small size of the LED module 30 provides versatility so that modules can be mounted at various places and in various configurations. For instance, some applications will include only a single module for a particular lighting application, while other lighting applications will employ a plurality of modules electrically connected in parallel relative to each other.
[0054] It is also to be understood that any number of LEDs can be included in one module. For example, some modules may use two LEDs, while other modules may use 10 or more LEDs. One manner of determining the number of LEDs to include in a single module is to first determine the desired operating voltage of a single LED of the module and also the voltage of the power supply. The number of LEDs desired for the module is then roughly equal to the voltage of the power supply divided by the operating voltage of each of the LEDs.
[0055] The present invention rapidly conducts heat away from the diode chip 34 of each LED 32 so as to permit the LEDs 32 to be operated in regimes that exceed normal operating parameters of the pre-packaged LEDs 32 . In particular, the heat sinks allow the LED circuit to be driven in a continuous, non-pulsed manner at a higher long-term electrical current than is possible for typical LED mounting configurations. This operating current is substantially greater than manufacturer-recommended maximums. The optical emission of the LEDs at the higher current is also markedly greater than at manufacturer-suggested maximum currents.
[0056] The heat transfer arrangement of the LED modules 30 is especially advantageous for pre-packaged LEDs 32 having relatively small packaging and for single-diode LED lamps. For instance, the HLMT-PL00 model LED lamps used in the illustrated embodiment employ only a single diode, but since heat can be drawn efficiently from that single diode through the leads and circuit board and into the heat sink, the diode can be run at a higher current than such LEDs are traditionally operated. At such a current, the single-diode LED shines brighter than LED lamps that employ two or more diodes and which are brighter than a single-diode lamp during traditional operation. Of course, pre-packaged LED lamps having multiple diodes can also be employed with the present invention. It is also to be understood that the relatively small packaging of the model HLMT-PL00 lamps aids in heat transfer by allowing the heat sink to be attached to the leads closer to the diode chip.
[0057] With next reference to FIG. 5 , a first reflective layer 80 is preferably attached immediately on top of the contacts 60 of the circuit board 50 and is held in position by the rivets 72 . The first reflector 80 preferably extends outwardly beyond the LEDs 32 . The reflective material preferably comprises an electrically non-conductive film such as visible mirror film available from 3M. A second reflective layer 82 is preferably attached to the mount member 76 at a point immediately adjacent the LED lamps 32 . The second strip 82 is preferably bonded to the mount surface 76 using adhesive in a manner known in the art.
[0058] With reference also to FIG. 6 , the first reflective strip 80 is preferably bent so as to form a convex reflective trough about the LEDs 32 . The convex trough is adapted to direct light rays emitted by the LEDs 32 outward with a minimum of reflections between the reflector strips 80 , 82 . Additionally, light from the LEDs is limited to being directed in a specified general direction by the reflecting films 80 , 82 . As also shown in FIG. 6 , the circuit board 50 can be mounted directly to any mount surface 76 .
[0059] In another embodiment, the aluminum main body portion 56 may be of reduced thickness or may be formed of a softer metal so that the module 30 can be partially deformed by a user. In this manner, the module 30 can be adjusted to fit onto various surfaces, whether they are flat or curved. By being able to adjust the fit of the module to the surface, the shared contact surface between the main body and the adjacent heat sink is maximized, improving heat transfer properties. Additional embodiments can use fasteners other than rivets to hold the module into place on the mount surface/heat sink material. These additional fasteners can include any known fastening means such as welding, heat conductive adhesives, and the like.
[0060] As discussed above, a number of materials may be used for the circuit board portion of the LED module. With specific reference to FIG. 7 , another embodiment of an LED module 86 comprises a series of elongate, flat contacts 88 similar to those described above with reference to FIG. 3 . The contacts 88 are mounted directly onto the main body portion 89 . The main body 89 comprises a rigid, substantially flat ceramic plate. The ceramic plate makes up the bulk of the circuit board and provides structural support for the contacts 88 . Also, the ceramic plate has a surface area about the same as the combined surface area of the contacts. In this manner, the plate is large enough to provide structural support for the contacts 88 and conduct heat away from each of the contacts 88 , but is small enough to allow the module 86 to be relatively small and easy to work with. The ceramic plate 89 is preferably electrically non-conductive but has high heat conductivity. Thus, the contacts 88 are electrically insulated relative to each other, but heat from the contacts 88 is readily transferred to the ceramic plate 89 and into an adjoining heat sink.
[0061] With next reference to FIG. 8 , another embodiment of an LED lighting module 90 is shown. The LED module 90 comprises a circuit board 92 having features substantially similar to the circuit board 50 described above with reference to FIG. 3 . The diode portion 94 of the LED 96 is mounted substantially directly onto the contacts 60 of the lighting module 90 . In this manner, any thermal resistance from leads of pre-packaged LEDs is eliminated by transferring heat directly from the diode 94 onto each heat sink contact 60 , from which the heat is conducted to the main body 56 and then out of the module 90 . In this configuration, heat transfer properties are yet further improved.
[0062] As discussed above, an LED module having features as described above can be used in many applications such as, for example, indoor and outdoor decorative lighting, commercial lighting, spot lighting, and even room lighting. With next reference to FIGS. 9-12 , a self-contained lighting apparatus 100 incorporates an LED module 30 and can be used in many such applications. In the illustrated embodiment, the lighting apparatus 100 is adapted to be installed on the side of a row of theater seats 102 , as shown in FIG. 13 , and is adapted to illuminate an aisle 104 next to the theater seats 102 .
[0063] The self-contained lighting apparatus 100 comprises a base plate 106 , a housing 108 , and an LED module 30 arranged within the housing 108 . As shown in FIGS. 9 , 10 and 13 , the base plate 106 is preferably substantially circular and has a diameter of about 5.75 inches. The base plate 106 is preferably formed of 1/16 th inch thick aluminum sheet. As described in more detail below, the plate functions as a heat sink to absorb and dissipate heat from the LED module. As such, the base plate 106 is preferably formed as large as is practicable, given aesthetic and installation concerns.
[0064] As discussed above, the lighting apparatus 100 is especially adapted to be mounted on an end panel 110 of a row of theater chairs 102 in order to illuminate an adjacent aisle 104 . As shown in FIGS. 13 and 14 , the base plate 106 is preferably installed in a vertical orientation. Such vertical orientation aids conductive heat transfer from the base plate 106 to the environment.
[0065] The base plate 106 includes three holes 112 adapted to facilitate mounting. A ratcheting barb 116 (see FIG. 15 ) secures the plate 106 to the panel 110 . The barb 116 has an elongate main body 118 having a plurality of biased ribs 120 and terminating at a domed top 122 .
[0066] To mount the apparatus on the end panel 110 , a hole is first formed in the end panel surface on which the apparatus is to be mounted. The base plate holes 112 are aligned with mount surface holes and the barbs 116 are inserted through the base plate 106 into the holes. The ribs 120 prevent the barbs 116 from being drawn out of the holes once inserted. Thus, the apparatus is securely held in place and cannot be easily removed. The barbs 116 are especially advantageous because they enable the device to be mounted on various surfaces. For example, the barbs will securely mount the illumination apparatus on wooden or fabric surfaces.
[0067] With reference next to FIGS. 16-19 , a mount tab 130 is provided as an integral part of the base plate 106 . The mounting tab 130 is adapted to receive an LED module 30 mounted thereon. The tab 130 is preferably plastically deformed along a hinge line 132 to an angle θ between about 20-45° relative to the main body 134 of the base plate 106 . More preferably, the mounting tab 130 is bent at an angle θ of about 33°. The inclusion of the tab 130 as an integral part of the base plate 106 facilitates heat transfer from the tab 130 to the main body 134 of the base plate. It is to be understood that the angle θ of the tab 130 relative to the base plate body 134 can be any desired angle as appropriate for the particular application of the lighting apparatus 100 .
[0068] A cut out portion 136 of the base plate 106 is provided surrounding the mount tab 130 . The cut out portion 136 provides space for components of the mount tab 130 to fit onto the base plate 106 . Also, the cut out portion 136 helps define the shape of the mount tab 130 . As discussed above, the mount tab 130 is preferably plastically deformed along the hinge line 132 . The length of the hinge line 132 is determined by the shape of the cut out portion 136 in that area. Also, a hole 138 is preferably formed in the hinge line 132 . The hole 138 further facilitates plastic deformation along the hinge line 132 .
[0069] Power for the light source assembly 100 is preferably provided through a power cord 78 that enters the apparatus 100 through a back side of the base plate 106 . The cord 78 preferably includes two 18 AWG conductors surrounded by an insulating sheet. Preferably, the power supply is in the low voltage range. For example, the power supply is preferably a 12-volt alternating current power source. As depicted in FIG. 18 , power is preferably first provided through a full wave ridge rectifier 140 which rectifies the alternating current in a manner known in the art so that substantially all of the current range can be used by the LED module 40 . In the illustrated embodiment, the LEDs are preferably not electrically connected to a current-limiting resistor. Thus, maximum light output can be achieved. It is to be understood, however, that resistors may be desirable in some embodiments to regulate current. Supply wires 142 extend from the rectifier 140 and provide rectified power to the LED module 30 mounted on the mounting tab 130 .
[0070] With reference again to FIGS. 9-12 , 16 and 17 , the housing 108 is positioned on the base plate 106 and preferably encloses the wiring connections in the light source assembly 100 . The housing 108 is preferably substantially semi-spherical in shape and has a notch 144 formed on the bottom side. A cavity 146 is formed through the notch 144 and allows visual access to the light source assembly 100 . A second cavity 148 is formed on the top side and preferably includes a plug 150 which may, if desired, include a marking such as a row number. In an additional embodiment, a portion of the light from the LED module 30 , or even from an alternative light source, may provide light to light up the aisle marker.
[0071] The housing 108 is preferably secured to the base plate 106 by a pair of screws 152 . Preferably, the screws 152 extend through countersunk holes 154 in the base plate 106 . This enables the base plate 106 to be substantially flat on the back side, allowing the plate to be mounted flush with the mount surface. As shown in FIG. 17 , threaded screw receiver posts 156 are formed within the housing 108 and are adapted to accommodate the screw threads.
[0072] The LED module 30 is attached to the mount tab 130 by the pop rivets 72 . The module 30 and rivets 72 conduct heat from the LEDs 32 to the mount tab 130 . Since the tab 130 is integrally formed as a part of the base plate 106 , heat flows freely from the tab 130 to the main body 134 of the base plate. The base plate 106 has high heat conductance properties and a relatively large surface area, thus facilitating efficient heat transfer to the environment and allowing the base plate 106 to function as a heat sink.
[0073] As discussed above, the first reflective strip 80 of the LED module 30 is preferably bent so as to form a convex trough about the LEDs. The second reflector strip 82 is attached to the base plate mount tab 130 at a point immediately adjacent the LED lamps 32 . Thus, light from the LEDs is collimated and directed out of the bottom cavity 146 of the housing 108 , while minimizing the number of reflections the light must make between the reflectors (see FIG. 6 ). Such reflections may each reduce the intensity of light reflected.
[0074] A lens or shield 160 is provided and is adapted to be positioned between the LEDs 32 and the environment outside of the housing cavity 108 . The shield 160 prevents direct access to the LEDs 32 and thus prevents harm that may occur from vandalism or the like, but also transmits light emitted by the light source 100 .
[0075] FIG. 20 shows an embodiment of the shield 160 adapted for use in the present invention. As shown, the shield 160 is substantially lenticularly shaped and has a notch 162 formed on either end thereof. With reference back to FIG. 18 , the mounting tab 130 of the base plate 106 also has a pair of notches 164 formed therein.
[0076] As shown in FIG. 16 , the lens/shield notches 162 are adapted to fit within the tab notches 164 so that the shield 160 is held in place in a substantially arcuate position. The shield thus, in effect, wraps around one side of the LEDs 32 . When the shield 160 is wrapped around the LEDs 32 , the shield 160 contacts the first reflector film 80 , deflecting the film 80 to further form the film in a convex arrangement. The shield 160 is preferably formed of a clear polycarbonate material, but it is to be understood that the shield 160 may be formed of any clear or colored transmissive material as desired by the user.
[0077] The LED module 30 of the present invention can also be used in applications using a plurality of such modules 30 to appropriately light a lighting apparatus such as a channel illumination device. Channel illumination devices are frequently used for signage including borders and lettering. In these devices, a wall structure outlines a desired shape to be illuminated, with one or more channels defined between the walls. A light source is mounted within the channel and a translucent diffusing lens is usually arranged at the top edges of the walls so as to enclose the channel. In this manner, a desired shape can be illuminated in a desired color as defined by the color of the lens.
[0078] Typically, a gas-containing light source such as a neon light is custom-shaped to fit within the channel. Although the diffusing lens is placed over the light source, the light apparatus may still produce “hot spots,” which are portions of the sign that are visibly brighter than other portions of the sign. Such hot spots result because the lighting apparatus shines directly at the lens, and the lens may have limited light-diffusing capability. Incandescent lamps may also be used to illuminate such a channel illumination apparatus; however, the hot spot problem typically is even more pronounced with incandescent lights.
[0079] Both incandescent and gas-filled lights have relatively high manufacturing and operation costs. For instance, gas-filled lights typically require custom shaping and installation and therefore can be very expensive to manufacture. Additionally, both incandescent and gas-filled lights have high power requirements.
[0080] With reference next to FIG. 21 , an embodiment of a channel illumination apparatus 170 is disclosed comprising a casing 172 in the shape of a “P.” The casing 172 includes a plurality of walls 174 and a bottom 176 , which together define at least one channel. The surfaces of the walls 174 and bottom 176 are diffusely-reflective, preferably being coated with a flat white coating. The walls 174 are preferably formed of a durable sturdy metal having relatively high heat conductivity. A plurality of LED lighting modules 30 are mounted to the walls 174 of the casing 172 in a spaced-apart manner. A translucent light-diffusing lens (not shown) is preferably disposed on a top edge 178 of the walls 174 and encloses the channel.
[0081] With next reference to FIG. 22 , the pop rivets 72 hold the LED module 30 securely onto a heat conductive mount tab 180 . The mount tab 180 , in turn, may be connected, by rivets 182 or any other fastening means, to the walls 174 of the channel apparatus as shown in FIG. 23 . Preferably, the connection of the mount tab 180 to the walls 174 facilitates heat transfer from the tab 180 to the wall 174 . The channel wall has a relatively large surface area, facilitating efficient heat transfer to the environment and enabling the channel wall 174 to function as a heat sink.
[0082] In additional embodiments, the casing 172 may be constructed of materials, such as certain plastics, that may not be capable of functioning as heat sinks because of inferior heat conductance properties. In such embodiments, the LED module 30 can be connected to its own relatively large heat sink base plate, which is mounted to the wall of the casing. An example of such a heat sink plate in conjunction with an LED lighting module has been disclosed above with reference to the self-contained lighting apparatus 100 .
[0083] With continued reference to FIGS. 22 and 23 , the LED modules 30 are preferably electrically connected in parallel relative to other modules 30 in the illumination apparatus 170 . A power supply cord 184 preferably enters through a wall 174 or bottom surface 176 of the casing 172 and preferably comprises two 18 AWG main conductors 186 . Short wires 188 are attached to the first and last contacts 62 , 64 of each module 30 and preferably connect with respective main conductors 186 using insulation displacement connectors (IDCs) 190 as shown in FIG. 23 .
[0084] Although the LEDs 32 in the modules 30 are operated at currents higher than typical LEDs, the power efficiency characteristic of LEDs is retained. For example, a typical channel light employing a neon-filled light could be expected to use about 60 watts of power during operation. A corresponding channel illumination apparatus 170 using a plurality of LED modules can be expected to use about 4.5 watts of power.
[0085] With reference again to FIG. 23 , the LED modules 30 are preferably positioned so that the LEDs 32 face generally downwardly, directing light away from the lens. The light is preferably directed to the diffusely-reflective wall and bottom surfaces 174 , 176 of the casing 172 . The hot spots associated with more direct forms of lighting, such as typical incandescent and gas-filled bulb arrangements, are thus avoided.
[0086] The reflectors 80 , 82 of the LED modules 30 aid in directing light rays emanating from the LEDs toward the diffusely-reflective surfaces. It is to be understood, however, that an LED module 30 not employing reflectors can also be appropriately used.
[0087] The relatively low profile of each LED module 30 facilitates the indirect method of lighting because substantially no shadow is created by the module when it is positioned on the wall 174 . A higher-profile light module would cast a shadow on the lens, producing an undesirable, visibly darkened area. To minimize the potential of shadowing, it is desired to space the modules 30 and accompanying power wires 186 , 188 a distance of at least about 2 inch from the top edge 178 of the wall 174 . More preferably, the modules 30 are spaced more than one inch from the top 178 of the wall 174 .
[0088] The small size and low profile of the LED modules 30 enables the modules to be mounted at various places along the channel wall 174 . For instance, with reference to FIGS. 21 and 24 , light modules 30 must sometimes be mounted to curving portions 192 of walls 174 . The modules 30 are preferably about 1 inch to 1½ inch long, including the mounting tab 180 , and thus can be acceptably mounted to a curving wall 192 . As shown, the mounting tab 180 may be separated from the curving wall 192 along a portion of its length, but the module is small enough that it is suitable for riveting to the wall.
[0089] In an additional embodiment shown in FIG. 25 , the module 30 comprises the circuit board without the mount tab 180 . In such an embodiment, the circuit board 50 may be mounted directly to the wall, having an even better fit relative to the curved surface 192 than the embodiment using a mount tab. In still another embodiment, the LED module's main body 56 is formed of a bendable material, which allows the module to fit more closely and easily to the curved wall surface.
[0090] Although the LED modules 30 disclosed above are mounted to the channel casing wall 174 with rivets 182 , it is to be understood that any method of mounting may be acceptably used. With reference next to FIGS. 26A-C , an additional embodiment comprises an LED module 30 mounted to a mounting tab 200 which comprises an elongate body portion 202 and a clip portion 204 . The clip portion 204 is urged over the top edge 178 of the casing wall 172 , firmly holding the mounting tab 200 to the wall 174 as shown in FIG. 26B . The lens 206 preferably has a channel portion 208 which is adapted to engage the top edge 178 of the casing wall 174 and can be fit over the clip portion 204 of the mount tab 200 as shown in FIGS. 26B and 26C . This mounting arrangement is simple and provides ample surface area contact between the casing wall 174 and the mounting tab 200 so that heat transfer is facilitated.
[0091] In the embodiment shown in FIG. 21 , the casing walls 174 are about 3 to 4 inches deep and the width of the channel is about 3 to 4 inches between the walls. In an apparatus of this size, LED modules 30 positioned on one side of the channel can provide sufficient lighting. The modules are preferably spaced about 5-6 inches apart. As may be anticipated, larger channel apparatus will likely require somewhat different arrangements of LED modules, including employing more LED modules. For example, a channel illumination apparatus having a channel width of 1 to 2 feet may employ LED modules on both walls and may even use multiple rows of LED modules. Additionally, the orientation of each of the modules may be varied in such a large channel illumination apparatus. For instance, with reference to FIG. 26D , some of the LED modules may desirably be angled so as to direct light at various angles relative to the diffusely reflective surfaces.
[0092] In order to avoid creating hot spots, a direct light path from the LED 32 to the lens 206 is preferably avoided. However, it is to be understood that pre-packaged LED lamps 32 having diffusely-reflective lenses may advantageously be directed toward the channel letter lens 206 .
[0093] Using LED modules 30 to illuminate a channel illumination apparatus 170 provides significant savings during manufacturing. For example, a number of LED modules, along with appropriate wiring and hardware, can be included in a kit which allows a technician to easily assemble a light by simply securing the modules in place along the wall of the casing and connecting the wiring appropriately using the IDCs. Although rivet holes may have to be drilled through the wall, there is no need for custom shaping, as is required with gas-filled bulbs. Accordingly, manufacturing effort and costs are significantly reduced.
[0094] Individual LEDs emit generally monochromatic light. Thus, it is preferable that an LED type be chosen which corresponds to the desired illumination color. Additionally, the diffuser is preferably chosen to be substantially the same color as the LEDs. Such an arrangement facilitates desirable brightness and color results. It is also to be understood that the diffusely-reflective wall and bottom surfaces may advantageously be coated to match the desired illumination color.
[0095] Although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically-disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. In addition, while a number of variations of the invention have been shown and described in detail, other modifications, which are within the scope of this invention, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or subcombinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the invention. Accordingly, 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 invention. Thus, it is intended that the scope of the present invention 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 modular light emitting diode (LED) mounting configuration is provided including a light source module having a plurality of pre-packaged LEDs arranged in a serial array. The module includes a heat conductive body portion adapted to conduct heat generated by the LEDs to an adjacent heat sink. As a result, the LEDs are able to be operated with a higher current than normally allowed. Thus, brightness and performance of the LEDs is increased without decreasing the life expectancy of the LEDs. The LED modules can be used in a variety of illumination applications employing one or more modules. | 8 |
TECHNICAL FIELD
This invention generally pertains to a microcomputer based momentary power loss fault detector for use with three-phase circuits. More particularly, it relates to a uniquely reliable fault detector and fault detection method for initiating a disconnect of an induction motor from a source of three-phase power in response to the detection of a momentary power loss.
BACKGROUND OF THE INVENTION
Induction motors are widely used electric motors. Such motors include a fixed stator that is mounted inside the motor casing. The stator comprises a series of stationary windings with a large cylindrical opening in the center. A rotor having a series of windings mounted on a rotatable shaft is mounted inside the stator opening. The rotor is free to revolve within the opening. Application of electric power to the stator produces a rotating magnetic field in the stator, which induces high currents in the rotor. The rotor currents, in turn, produce their own magnetic fields, which interact with the main field generated in the stator and make the rotor turn.
Induction motors are easy to manufacture and are essentially trouble-free in actual service. In a practical induction motor, the rotor consists of a laminated iron core which is slotted lengthwise all around its periphery. Solid bars of aluminum, copper or other conductors are tightly pressed or imbedded into the slots. At both ends of the rotor, short-circuiting rings are welded or brazed to the bars to make a solid structure for placement on the iron core. The short circuiting rings actually form shorted turns that have currents induced in them by the field flux. When assembled, the periphery of the rotor is separated from the stator by a very small air gap. The width of the air gap is as small as mechanically possible to ensure that the strongest possible electromagnetic induction takes place.
For the induction motor to run, the rotor must rotate at a slightly slower speed than the rotating magnetic field of the stator. If the rotor turned at exactly the same speed as the stator field, there would be no relative difference in motion between the field and the rotor. The bars in the rotor would not cut the field flux lines and no current would be induced in the rotor. The difference between the field and the rotor speed is known as slip. Rotors tend to slip behind the field speed by two to ten percent and the slip will increase as the load on the motor increases.
Three-phase inductive motors, as well as many other three-phase loads, are susceptible to damage due to momentary power supply faults, such as are caused by line power loss and buss transfers. Simply put, this means that to momentarily shut off the power to an operating electric motor and then turn the power back on again while the motor is still spinning may cause damage to the motor and to the equipment that the motor was driving at the time of the power interrupt. A procedure is needed, therefor, to detect when the power has been turned off and to disconnect the motor from the power line before the power is restored, so that when the power is restored., it is not fed to the motor. By doing this, damage to the motor and the equipment that is being powered by the motor is avoided.
As indicated, the purpose of momentary power loss protection is to protect the inductive motor and related components from the damaging effects of power interruptions. Related components that can be damaged by a power interruption may include compressor impellers, shaft key ways, and starter contacts.
Power interruptions can result from loss of external line power and internal buss transfers. An external line power failure is failure of the power as it comes from the power utility generating station. Such failures may occur due to weather effects on the line transmission equipment or from the switching of generator sources at the power utility, or from a failure at the power utility. An internal buss transfer comprises a switch from one power source to another, such as might occur when automatically switching from external utility line power to a backup generator at the facility in which the motor is installed. It should be remembered that the types of faults that this invention is concerned with are those in which there is a momentary loss of power followed virtually immediately by a restoration of power.
Momentary power interruptions may be unexpected as in the case of power line switching closures, brownouts and substation transfers. They may also be expected, resulting from buss transfers to an alternate power source within a facility. Whether expected or unexpected, interruptions result in large transient currents up to twelve times full load amperage and transient torques up to twelve times full load torque or twenty times full load torque if power factor correction capacitors are used in conjunction with the induction motor.
In inductive motors, the reconnection currents that are presented due to a momentary power loss generate large electromagnetic forces between neighboring stator windings as well as between the rotor bars. This exposes the stator end windings and the rotor shorting rings to excessive stress. This stress has been identified through studies and experience as causing or accelerating motor failures. Failure of the motor is typically not immediate but is most often seen as accelerated wear and greatly reduced motor life.
The large transient torques that result from the loss of power and quick reapplication of the power may be negative at times. Such negative torques may attempt to reverse the direction of rotation of the motor and cause damage to the equipment that is being powered by the motor. Impellers that may be powered by an induction motor, for instance, are often affixed to the shaft on which the impellers rotate by aligned grooves or key ways in the shaft and the impeller. A key is inserted in the key ways to rotationally mate the impeller to the shaft. Slapping of the key ways and exposure of the impellers to large mechanical stresses can occur as the result of a momentary power loss that causes the motor to try to reverse direction of rotation by the transient torques.
The above potentially damaging interrupts need to be distinguished from noise on the line and from the loss of a single phase of the three-phase power. Noise can be the result of weather effects on the power received from the power lines, such as may be caused by an electrical storm or the switching on and off of nearby machines, and is usually a transient condition. Shutdowns of the motor as a result of detecting such occurrences as noise are considered nuisance shutdowns. Three phase power is alternating power and requires three lines to deliver the power. On occasion, one phase of the power is lost. In such instances, the motor will continue to operate, but in a single phase mode of operation. A single phase loss may cause motor damage and is detected using a separate and slower mechanism.
Although a wide variety of fault detectors for use in three-phase circuits are presently available, the time response window of conventional fault detectors is inadequate. Some conventional detectors respond too slowly to critical faults and damage can quickly occur when the detector does not interrupt the power supply before power is restored. Other detectors respond too quickly to less critical faults where a slower response would avoid false alarms.
Moreover, in many applications, conventional fault detectors do not distinguish a momentary power loss from noise. As a result, such detectors needlessly trip the motor off in the presence of mere noise on the lines. A false trip may also occur in the event of a loss of one phase of the line power. It is desirable to absolutely minimize such false trips, since they are costly in the maintenance actions required to reinitialize the motor and the equipment powered by the motor and in lost time for the work which the motors are intended to be performing.
The ultimate goal of momentary power loss protection circuits is to disconnect the motor from the power line before the duration of the interruption allows the reconnection currents and torques to achieve a damaging level. For very short power interruptions (defined here as less than 1 to 2 line cycles), the reconnection transients are less than those seen for a normal start of the motor and, therefore, are not destructive to the motor. It is just as well that the motor not be decoupled in the event of such short duration power losses so that the motor will be powered again when power is restored after the short interrupt. Since the motor is not injured by the reapplication of power, this avoids an unnecessary shutdown.
Likewise, for very long power interruptions (defined here as greater than six seconds), the reconnection transients are also below the transients seen for a normal start of the motor. As is indicated above, in cases where the reconnection transient is less than the current and torque experienced during a normal start-up, the motor will not be injured by the reconnection and it is desirable to permit such reconnection to occur in order to avoid an unnecessary shutdown.
Power interruptions of a duration between the above defined short and long power interruptions result in reconnections which are potentially destructive to the motor. Optimal momentary power loss protection would protect the motor from reconnections falling within that window of time, but would not permanently disconnect power when momentary power losses of a duration outside of the designated time window are detected. No adequate momentary power loss protection for the defined duration currently exists. The main function of the present invention is to disconnect the motor from the line in the event of power interruptions lasting for more than one or two line cycles. Thus when a long interruptions occurs, the motor has already been removed from the line power source.
It is accordingly an object of the present invention to provide a momentary power loss detection system that is capable of distinguishing faults that occur in a time regime between short duration power faults and long duration power faults.
It is another object of the present invention to provide a momentary power loss detector that is microcomputer based, thereby minimizing the number of discrete electrical elements necessary to perform the detection function.
Still another object of the present invention is to provide a momentary power loss detection system in which robustness of the data is inherent.
These and other objects of the invention will be apparent from the attached drawings and the description of the preferred embodiment which follow hereinbelow.
SUMMARY OF THE INVENTION
The present invention is a device and method for reliably detecting a momentary power loss of the desired duration; the duration being between a minimum of one to two line cycles and a maximum of six seconds. The invention accomplishes this while avoiding false shutdowns due to noise and power phase loss. The invention is able to distinguish a momentary power loss that is due to a utility line loss and to a buss transfer and thereby provides a reliable signal with which to initiate disconnecting the motor from the power source in the event of detecting such power failures.
The apparatus in accordance with the present invention is a fault detector for detecting a momentary power loss in a three-phase, alternating current power supply, the power supply being connected to and powering a motor. The fault detector includes a detector circuit which has a microprocessor for detecting when the motor switches from a mode of operation as a motor to a mode of operation as a generator. The microprocessor, upon detecting a motor mode switch of operation, generates a fault disconnect signal in response thereto to initiate disconnecting the motor from the power source.
The method in accordance with the present invention includes a procedure for detecting a momentary power loss in a three-phase, alternating current, power supply, the power supply being connected to and powering a motor. The method includes the steps of detecting when the motor switches from a mode of operation as a motor to a mode of operation as a generator and then generating a fault disconnect signal in response thereto to initiate disconnecting the motor from the power source.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram depicting a momentary power loss circuit in accordance with the present invention in conjunction with a three phase power supply and a three phase inductive motor;
FIG. 2 is a vector diagram of the voltages presented to an inductive motor immediately after a momentary power loss;
FIG. 3 is a vector diagram of the voltages present to the motor after a momentary power loss when the line voltage and the motor's regenerated voltage are 180° out of phase;
FIG. 4 is a vector diagram of the voltages present to the motor after a momentary power loss when the line voltage and the motor's regenerated voltage are 60° out of phase;
FIG. 5 is a diagram of power flow based on power factor;
FIG. 6 illustrates electrical wave forms representative of line current and line to line voltage in the inductive motor as presented to the microprocessor of the momentary power loss detector; and
FIG. 7 is a logic sequence of the routine that the microcomputer follows to determine if a momentary power loss fault exists.
DESCRIPTION OF THE PREFERRED EMBODIMENT
During a loss of power, the residual flux of an induction motor, as it rotates in an unpowered condition, is great enough to produce a generated voltage and regeneration of the generated voltage back into the utility power grid. The regeneration into the utility power grid provides adequate excitation to keep the motor contact pulled in, thereby keeping the motor connected to the main power lines. For very short duration power losses, while the motor is still connected to the utility main power lines, the difference of the line voltage and the motor's regenerated voltage appears at the motor terminals, as indicated in the following analysis.
Immediately after a loss of power, the regenerated voltage measured at the motor terminals is in phase with, and approximately ninety percent of the magnitude of the line voltage. This condition is depicted in FIG. 2, where the line voltage vector is illustrated at 10, the regenerated voltage is illustrated at 12, and the resultant voltage vector is illustrated at 14. The resultant voltage 14 at this time is small and no damage will occur if reclosure would take place within this very short time. The angular difference between the line voltage 10 and the regenerated voltage 12 is a function of elapsed time from the time of the occurrence of the momentary power loss and the time of reapplication of the line power to the motor. The elapsed time that is depicted in FIG. 2 is less than two line cycles.
As time progresses from the occurrence of the momentary power loss, the phase difference between the voltages becomes greater due to the unpowered motor (now acting as a generator) slowing down and no longer operating at slip speed with the line power. The motor is now operating at less than the slip speed. Extreme reclosure currents can occur when the line voltage 10 and the motor's regenerated voltage 12 are 180 degrees out of phase at the time that the line power is reapplied to the motor. This condition is depicted in FIG. 3, where, as in FIG. 1, the line voltage vector is illustrated at 10, the regenerated voltage is illustrated at 12, and the resultant voltage vector is illustrated at 14. In this condition the resultant voltage vector 14 would be approximately twice the line voltage 10 assuming that the magnitude of the induced voltage did not decay significantly. During reapplication of line power, this excessive resultant voltage 14 present at the motor terminals causes in-rush currents of approximately two times the current experienced by the motor during a normal across-the-line start which is approximately twelve times the full load current.
The safe area of reapplication of line power occurs as depicted in FIG. 4, where the resultant voltage 14 is no greater in magnitude than the line voltage 10. This results in in-rush currents no greater than a normal across-the-line start of the motor. This is possible when the phase difference between the line voltage 10 and regenerated voltage 12 is less than 60°. When the line voltage and regenerated voltage are approximately equal in magnitude, and out of phase by 60°, the vector addition drawing illustrates that this forms an equilateral triangle, guaranteeing that the magnitude of the resultant voltage 14 is the same as the magnitude of the line voltage 10.
It is known that the maximum transient electrical torque occurs when the regenerated voltage is 0.95 per-unit as compared to line voltage with a reapplication angle of 120° between the regenerated voltage and the line voltage. These parameters yield a peak torque of 12.3 times the normal torque. It has also been shown that with lower regenerated voltages (less than 0.30 per-unit), the peak electrical torque occurs at a reapplication angle of about 90°. Reclosure under that condition results in a peak transient torque of 2.53 per-unit, or 127% of the rated motor pullout torque. It should be noted that these exact figures are motor dependent, but do not deviate significantly from motor to motor.
In order to protect the motor from these potentially damaging excessive torques and currents, the motor contact should be opened, disconnecting the motor from the power lines before these conditions appear, e.g. before reapplication of power from the power lines occurs. As stated earlier, momentary power losses of very short duration (less than two frequency cycles) are not damaging to the motor because the angle between the applied voltage and regenerated voltage is minimal. For an interrupt of significantly greater duration, when the regenerated voltage has decayed to less than twenty-five percent of the line voltage, the peak torques and currents resulting from reapplication of line power are also known to be non-damaging. Such losses typically have a duration in excess of six seconds. It is the momentary power losses that fall in the window between these two non-damaging losses that the motor needs to be protected from.
Protection of the motor starts with the detection of the power loss condition. This is accomplished by determining when the motor leaves the motor operation mode and enters the generator operation mode. This detection can be achieved by observing the phase relationships between the motor's voltage and current. Based on the fact that power flow and power factor are directly related, it can be determined if the motor is functioning as a motor or as a generator. A positive power factor exists when the motor is consuming power and a negative power factor exists when the motor is delivering (or generating) power. When the motor is generating power, a momentary power loss condition definitely exists. These relationships are depicted in FIG. 5, which is a plot of power flow as indicated by power factor, PF. FIG. 5 shows four distinct quadrants 16, 18, 20, 22. Each quadrant 16, 18, 20, 22 is defined by the phase angle (theta) of current I with respect to the voltage V. In FIG. 5 the voltage vector is defined as a reference at a phase angle of 0°. The current vector may move with respect to the voltage vector through phase angles of 0° to 360°. Since the quadrants are defined by the phase angle of the current I with respect to the voltage V, the four quadrants can be represented as a first quadrant 16 having a phase angle of 0° to 90°, a second quadrant 22 having a phase angle of 90° to 180°, a third quadrant 20 having a phase angle of 180° through 270°, and a fourth quadrant 18 having a phase angle of 270° through 360° (or 0°).
Power factor, PF, is the ratio of true power (power actually consumed) to apparent power (simple product of voltage and current). Since the power factor PF is defined in terms of the relationship of the current vector with respect to the voltage vector, the power factor is directly indicated by the phase angle (theta). When the motor 44 is consuming power by acting in a motor mode, the phase angle (theta) of the current I with respect to the voltage V falls in the quadrants 16 and 18. Quadrants 16 and 18 are therefore considered to be the positive power factor region. When the motor 44 is regenerating power by acting in a generator mode, the phase angle (theta) of the current I with respect to the voltage V falls within quadrants 20 and 22. Thus quadrants 20 and 22 are considered to be the negative power factor region.
Quadrant 18 represents an induction motor operating in the motor mode. Quadrant 16 represents an induction, synchronous or other type of motor operating in the motor mode but either being excited to appear capacitive or being modified by the addition of over sized power factor correction capacitors. Quadrant 22 represents a motor operating in a generator mode so as to regenerate into a predominantly inductive power line. Quadrant 20 represents a motor operating in a generator mode so as to regenerate into a predominantly capacitive power line. Operation in quadrants 16 and 18 represents the normal running condition of the motor, while operation in quadrants 20 and 22 is indicative of a momentary power loss condition.
Power factor PF is independent of the magnitude of the current I and the magnitude of the voltage V, but is dependent upon the phase angle (theta) of the current I with respect to the voltage V. The present invention detects the positive or negative polarity of the power factor PF to determine whether the operating mode is as a motor or as a generator. It is not necessary to actually calculate the magnitude of the power factor.
Instead, to determine the polarity of the power factor, the present invention examines the line to line voltage, Vab, and the phase current, Ic. By convention, the three phases of the line power are designated by the subscripts a, b, and c. The relationships (using squared up sine waves) are depicted in FIG. 6, where sine wave 24 represents the line to line voltage, Vab, sine wave 26 represents the current Ic with a capacitive load, sine wave 28 represents the current Ic with a resistive load, wave 30 represents the current Ic with a inductive load, and sine wave 32 represents the current Ic with a negative power factor. Thus the sine waves 26, 28 and 30 each represent a positive power factor and a normal operating condition of the motor 44, while the sine wave 32 generally represents a negative power factor and an abnormal operating condition of the motor 44.
For all types of loads, whether capacitive, resistive, or inductive as depicted by the sine waves 26, 28, and 30, it is noted, by referring to dashed lines 34, that for all positive going edges of Vab, Ic is positive and for all negative going edges of Vab, Ic is negative. A positive Ic represents a logic state of 1, or a high logic state. A negative Ic represents a logic state of zero, or a low logic state. This represents the situation when the motor is operating as a motor. As soon as the motor commences to function as a generator (due to a momentary power loss), this relationship no longer holds true. In fact, it is just the opposite logic. As depicted in sine wave 32, for all positive going edges of Vab, Ic is negative, for all negative going edges of Vab, Ic is positive. Squared sine waves 26, 28, and 30 represent conditions of positive power factor when the motor is operating as a motor. Squared sine wave 32 represents the condition of negative power factor when the motor is operating as a generator. It is this relationship of the opposite logic for the motor mode of operation and generator mode of operation that forms the basis for the momentary power loss detection strategy of the present invention.
The block diagram depicted in FIG. 1 illustrates the hardware implementation portion of the momentary power loss detection scheme of the present invention. A three-phase alternating power supply 36 provides electrical power through conductors 38, 40, and 42 to a three-phase inductive motor 44. Three-phase contact 46 provides a switching device to isolate the motor 44 from the power supply 36, as desired. The three phases of supply 36 are referred to as a, b, and c, corresponding to conductors 38, 40, and 42 respectively. Transformers 48, 50, and 66 provide current and voltage signals to zero cross detectors 52, 54, and 68 respectively. Zero cross detectors 52 and 68 provide squared sine wave signals to the microprocessor 58. Zero cross detector 54 provides a squared sine wave signal to a digital delay 62, which in turn applies a selected time delay to the signal and then sends the signal to the microprocessor 58. The microprocessor 58 applies programmed logic to the incoming signals and determines if a momentary power loss condition exists.
Referring again to FIG. 1 for the description of the detection technique, the line to line voltage Vab is obtained from a potential transformer (PT) 48 and the phase current Ic is obtained from a current transformer (CT) 50, both sized accordingly for the motor application. These signals are fed into zero cross detectors 52, 54, respectively. The zero cross detectors 52, 54 take the input AC signals of varying magnitude and output a 50% duty cycle, logic level squared signal. The output 56 of the zero cross detector 52 is provided directly to the microprocessor 58.
The output 60 of the zero cross detector 54 is also a 50% duty cycle, logic level, squared signal. The output 60 of the zero cross detector 54 is provided to the digital delay 62. The digital delay 62 for the phase current Ic is required to account for capacitive loads that may be used in conjunction with some inductive motors. In particular, the motor 44 will often have power factor correction capacitors installed. When operating in the generator mode, these capacitors present a highly capacitive load to the motor 44. If the motor 44 has a highly capacitive load and is acting as a generator, the motor will actually have Ic slightly leading Vab. Since Ic is slightly leading Vab, a motor in the generating mode operating into a purely capacitive power line would go undetected. This occurs because, for each positive going edge of Vab, Ic is positive and, for each negative going edge of Vab, Ic is negative. Consequently, regeneration into a purely capacitive power line appears to represent a positive power factor. In such case, a momentary power loss would go undetected, since the leading Ic has the same logic sense as Vab. By delaying the Ic signal, the proper phasing relationship is restored between Vab and Ic, so that the momentary power loss condition can be properly detected. After the delay, the delayed digital Ic measurement is then presented to the input of the microprocessor 58 by the output 64.
The Vab signal 56 is fed to an edge sensitive interrupt pin in the microprocessor 58. When the microprocessor 58 receives such an interrupt, the microprocessor 58 also reads the level of the Ic input pin 64. A test is made to determine if a momentary power loss condition exists. If microprocessor 58 sensed a positive going Vab edge and Ic is currently positive, the motor 44 may be operating as a motor. Similarly, when the Vab transition is negative going and Ic is negative, the motor 44 may be operating as a motor. If either of these tests fail, a possible momentary power loss condition exists. The motor 44 is in the motor mode of operation if the test at each of the positive and negative Vab transitions is satisfied such that Ic is respectively positive and negative.
Since noise conditions may be present and causing the possible momentary power loss detection, a judgment that a momentary power loss condition exists should not be made based solely on the detection of a single fault in the above logic. Care must be taken to prevent any nuisance trips, with motor 44 being disconnected from three-phase supply 36 by the microprocessor 58 when a momentary power loss has not actually occurred. Since the detection scheme of the present invention works on both positive and negative Vab transitions, there are twice as many opportunities to detect a momentary power loss condition as compared to only looking at one transition per cycle. This sampling twice per cycle permits obtaining a sufficient number of data samples in a short period of time to be reasonably sure that a true momentary power loss is present, as indicated by failing the test a reasonable number of times, while still providing sufficient time to disconnect the motor 44 from the three-phase supply 36 before a reapplication of power takes place. A reasonable number of failures is judged to be three. Since noise is random, there is a very low probability that the noise will cause three consecutive test failures, thereby minimizing noise as a source of false trips. Effectively, a fault disconnect signal can be generated in three half line cycles.
Three failures consecutively is the condition that exists when the motor 44 is regenerating current back into the utility grid, the utility grid being represented by three-phase supply 36. A different condition exists when the momentary power loss is due to a buss transfer. A buss transfer may occur, for instance when the power is transferred to a back-up generator as a result of a detected problem with the line power, such as a brown-out. During a buss transfer, the three-phase contact 46 is open while the transfer is being made from one buss to another. There is no current flow in any phase since the motor 44 is operating into an open circuit. The squared up Ic signal is no longer changing sinusoidally each cycle, but is remaining at either a positive or negative. A positive Ic represents a logic state of 1, or a high logic state. A negative Ic represents a logic state of zero, or a low logic state.
In the case described above, Ic will be either a constant positive or a constant negative. Therefore, when the microprocessor 58 receives an interrupt from a Vab transition, performing the above test reveals a momentary power loss only every other transition, since alternating samples of Vab and Ic will be of the sense that is seen in the motor mode. Accordingly, a buss transfer situation does not meet the three consecutive failures criteria. A second test is required to diagnose this momentary power loss that is due to a buss transfer. The second test recognizes the above alternating pattern and generates a momentary power loss condition signal if three out of the five past samples fail. This three out of five test allows good noise immunity as well as prompt diagnosis, with diagnosis occurring in two and a half power cycles.
This logic would be quite adequate except: for the possibility of a phase loss causing a misdiagnosis. A phase loss is the loss of power in either of the a, b, or c phases from the three-phase supply 36. Most phase losses are detected when the averaged phase current in the failed phase is detected to be significantly less than the other two phases. This averaging introduces a large time constant. The large time constant prevents diagnosis of this condition, within the two and a half cycle time constraint for diagnosing a momentary power loss, if only the average phase current is used to differentiate this condition from a true momentary power loss.
During a phase loss, the motor 44 is running in a single phase condition. The normal three phase voltage and current phase angle relationships depicted in FIG. 6 no longer are the same. The relationships in this condition depend upon which phase is lost. During a phase loss, there are three different conditions that can exist in the momentary power loss detection logic. During a loss of phase a, the momentary power loss algorithm senses a failure on three consecutive failures. During a loss of phase b, the momentary power loss algorithm does not sense any failure. During a loss of phase c, the momentary power loss algorithm fails due to a non-changing Ic. Loss of phase c looks like a buss transfer to the algorithm.
A second phase current, in addition to Ic, must be sampled in order to avoid misdiagnosing a phase loss as a momentary power loss. Accordingly, in FIG. 1, the current transformer 66 senses the a phase current, Ia, and provides that signal to the zero cross detector 68. The zero cross detector 68 provides an output 70 to the microprocessor 58 each time that Ia crosses the zero current condition.
The algorithm block diagram 76 depicted in FIG. 7 presents the series of steps performed by the microprocessor 58 to determine if a momentary power loss condition exists. The routine is entered as indicated at step 78. Step 80 is effectively a timing function upon which the remainder of the routine is based. The remainder of the routine is commenced at each Vab positive going transition and at each Vab negative going transition. Since this is a sine wave function, there are two of such transitions for each cycle.
At the time of transition of Vab, an input is provided to the microprocessor 58 that is representative of Ic and Ia in steps 82, 84 respectively. The Ic signal and the Vab signals are compared in the failure logic of step 86. Step 86 reads the logic state (polarity) of Ic at each of the positive and negative going transition states of the Vab. The test is considered passed if Ic is positive (high) for a positive going transition of Vab or if Ic is negative (low) for a negative going transition of Vab. If these states are not seen, the test at this particular Vab transition is considered failed. Step 88 determines the next action based upon the results of step 86. If the test did not fail, then the routine is exited. However, if the test did fail, the routine progresses to step 90.
Step 90 is utilized to ensure the robustness of the data. It is important that a high degree of certainty exist prior to disconnecting the motor 44. Accordingly, step 90 checks to see if the failure has registered on three consecutive transitions of Vab. If the answer is yes, the routine proceeds to step 92. Step 92 is a phase loss check. As indicated above, phase a current provides a good check to determine if a phase loss has occurred since the failure logic of step 86 fails on three consecutive transitions when there is a loss of phase a. Step 92 then looks to see if Ia is transitioning as a square sine wave. If Ia is still transitioning, then the three consecutive failures sensed in logic step 90 were due to a momentary power loss condition as opposed to a loss of phase. This is the case since a loss of phase a will be reflected as a phase that is not changing. When the answer to step 92 is yes, the microprocessor 58 provides a feedback signal to open the three-phase contact 46 and to isolate the motor 44 by opening contact 46.
When the answer developed by step 90 is no, it is known that the motor 44 is not regenerating, but there may still be a buss transfer problem that requires disconnecting the motor 44. Accordingly, step 94 looks to see if there is a failure on any three out of five transitions of Vab. As previously indicated, a buss transfer condition has a steady state Ic signal to the microprocessor 58 that will satisfy the motor mode logic on every other Vab transition. Therefore, the routine of step 94 looks at three of five transitions. If the answer is no (that there are not three of five failures), there is not a momentary power loss condition and the routine is exited. If the answer is yes, a final check to determine if a phase loss has occurred is made.
This final check is made by step 96. Step 96 again looks to see if Ia is transitioning as a squared sine wave. There is no sinusoidal transition of Ia in the event of a buss transfer problem. This is the case since the regenerated voltage produced by the motor 44 is not being fed into a load. Accordingly, all the currents are at either a positive or a negative state. This is an indication to distinguish a momentary power loss condition caused by a buss transfer problem from a phase loss problem. When the answer to step 96 is no (e.g., that Ia is not transitioning as a sine wave thereby indicating that a momentary power loss condition is present), the microprocessor 58 provides a feedback signal to open the three-phase contact 46 and to isolate the motor 44. If the answer to step 96 is yes, it is determined that momentary power loss does not exist, but that the problem is likely a phase loss and the routine is exited.
Although the invention is described with respect to a preferred embodiment, modifications thereto will become apparent to those skilled in the art. Therefore, the scope of the invention is to be determined by reference to the claims which follow. | An apparatus and method for protecting an induction motor from momentary power loss in a three-phase, alternating current, power supply. The apparatus includes a circuit for detecting when the motor switches from a mode of operation as a motor to a mode of operation as a generator, and a microprocessor connected to the detector to receive the detection of a switch in mode of operation, and for generating a fault disconnect signal in response thereto to initiate disconnecting the motor from the power source. The method includes the steps of detecting when the motor switches from a mode of operation as a motor to a mode of operation as a generator and generating a fault disconnect signal in response thereto to initiate disconnecting the motor from the power source. The apparatus and method provide for robustness of the fault detection data, and for avoiding false detections of momentary power loss. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a semiconductor device, and more particularly relates to a semiconductor device operated by a plurality of external voltages. The present invention also relates to a data processing system including a power supply device that generates different external voltages.
[0003] 2. Description of Related Art
[0004] An internal voltage used in a semiconductor device can be different from an external voltage supplied from outside. In this case, an internal voltage generating circuit that converts the external voltage into the internal voltage is prepared for the semiconductor. That is, when the external voltage is higher than the internal voltage, the external voltage is decreased by the internal voltage generating circuit. Conversely, when the external voltage is lower than the internal voltage, the external voltage is increased by the internal voltage generating circuit.
[0005] Some semiconductor devices use a plurality of internal voltages. In such semiconductor devices, a plurality of internal voltage generating circuits are provided (see Japanese Patent Application Laid-open No. 2007-13190).
[0006] In addition to the semiconductor device, other semiconductor devices and various electronic components are mounted on a mounting substrate of the semiconductor device and external voltages are supplied from power supply devices on the mounting substrate. Accordingly, plural types of external voltages can exist on the mounting substrate.
[0007] In the above case, when the semiconductor device with large consumption power relies on only an external voltage, the load of the power supply device that generates the corresponding external voltage becomes large. Particularly in semiconductor devices with greatly varying consumption power, the power supply device needs to be designed to supply the maximum consumption power, and thus the power supply device is difficult to be downsized.
SUMMARY
[0008] The present invention seeks to solve one or more of the above problems, or to improve upon those problems at least in part.
[0009] In one embodiment, there is provided a semiconductor device that includes a first internal voltage generating circuit that generates an internal voltage based on a first external voltage and a second internal voltage generating circuit that generates the internal voltage based on a second external voltage different from the first external voltage.
[0010] In another embodiment, there is provided a data processing system that includes a first power supply device that generates a first external voltage, a second power supply device that generates a second external voltage different from the first external voltage, and a semiconductor device operated by at least the first and second external voltages. The semiconductor device includes a first internal voltage generating circuit that generates an internal voltage based on the first external voltage and a second internal voltage generating circuit that generates the internal voltage based on the second external voltage.
[0011] Because the semiconductor device according to the present invention generates an internal voltage from a plurality of external voltages, it can utilize these external voltages efficiently according to the load state. Therefore, even in the semiconductor device with greatly varying consumption power, it is not necessary to enlarge only a particular power supply device. Accordingly, power supply devices used for a data processing system can be downsized.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The above features and advantages of the present invention will be more apparent from the following description of certain preferred embodiments taken in conjunction with the accompanying drawings, in which:
[0013] FIG. 1 is a block diagram of a data processing system according to a preferred embodiment of the present invention;
[0014] FIG. 2 is a block diagram of a configuration of the semiconductor device;
[0015] FIG. 3 is a circuit diagram showing an example of the internal voltage generating circuits;
[0016] FIG. 4 is another example of the internal voltage generating circuits;
[0017] FIG. 5 is still another example of the internal voltage generating circuits;
[0018] FIGS. 6A to 6C are waveform diagrams of the control signals;
[0019] FIG. 7 is a block diagram showing an example of adding an another internal voltage generating circuit to the semiconductor device shown in FIG. 2 ;
[0020] FIG. 8 is a preferred layout of the internal voltage generating circuits when the memory cell array is divided into four banks;
[0021] FIG. 9 is a circuit diagram of the sense amplifier and the sense amplifier driving circuit;
[0022] FIG. 10 is a circuit diagram of the power supply control circuit; and
[0023] FIG. 11 is a waveform diagram for explaining the sense operation of the semiconductor device according to the present embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0024] Preferred embodiments of the present invention will be explained below in detail with reference to the accompanying drawings.
[0025] FIG. 1 is a block diagram of a data processing system according to a preferred embodiment of the present invention.
[0026] As shown in FIG. 1 , the data processing system according to the present embodiment includes a power supply device 11 that generates an external voltage VDD 1 and a power supply device 12 that generates an external voltage VDD 2 . Both of the external voltages VDD 1 and VDD 2 are supplied to semiconductor devices 20 and 30 . The semiconductor devices 20 and 30 are operated by the two external voltages VDD 1 and VDD 2 . As an example, the semiconductor device 20 is a CPU (Central Processing Unit) and the semiconductor device 30 is a DRAM (Dynamic Random Access Memory), and these devices are connected to each other by a bus 40 . The configuration of the data processing system is not limited thereto and other devices, for example a semiconductor device such as graphic chips and a ROM, an external memory device such as a hard disk device and an optical drive, and an I/O device such as a keyboard and a speaker, can be connected to the bus 40 .
[0027] Maximum current supply capabilities (current limit values) in specs of systems are determined for the power supply devices 11 and 12 , respectively. Therefore, the semiconductor devices 20 and 30 that utilize the external voltages VDD 1 and VDD 2 can be supplied with power from the power supply devices 11 and 12 within the respective ranges of the current limit values. The current limit values of the power supply devices 11 and 12 depend on constituent elements in the systems, and as the power to be supplied is increased, the power supply device is designed to be enlarged.
[0028] Explanations are made below while focusing on the semiconductor device 30 , which is a DRAM.
[0029] FIG. 2 is a block diagram of a configuration of the semiconductor device 30 .
[0030] As shown in FIG. 2 , the semiconductor device 30 includes an internal voltage generating circuit 41 that generates an internal voltage VOD based on the external voltage VDD 1 and an internal voltage generating circuit 42 that generates the internal voltage VOD based on the external voltage VDD 2 . The external voltage VDD 1 is different from the external voltage VDD 2 . The external voltages VDD 1 and VDD 2 are supplied from outside via terminals T 1 and T 2 , respectively. The internal voltage VOD is thus generated from the different external voltages VDD 1 and VDD 2 . The semiconductor device 30 further includes an internal voltage generating circuit 44 that generates another internal voltage VARY from the external voltage VDD 1 (or the external voltage VDD 2 ).
[0031] Operations of the internal voltage generating circuits 41 and 42 are controlled by a power supply control circuit 50 . The power supply control circuit 50 selectively activates the internal voltage generating circuits 41 and 42 by control signals 41 a and 42 a and its selection is determined by an internal command ICMD. The internal command ICMD is an internal signal generated by a command decoder 61 that receives external commands CMD. The external command CMD is supplied from outside via terminals T 3 . For example, when the external command CMD indicates an active command, the command decoder 61 activates an active signal ACT which is one of the internal commands ICMD. When the external command CMD indicates a self refresh command, the command decoder 61 activates a refresh signal REF which is one of the internal commands ICMD.
[0032] The internal command ICMD is also supplied to an access control circuit 62 . The access control circuit 62 receives the internal command ICMD from the command decoder 61 and an internal address IADD from an address buffer 63 to select a memory cell designated by the internal address IADD among memory cells MC included in a memory cell array 64 . An external address ADD is supplied from outside via terminals T 4 . As shown in FIG. 2 , the memory cells MC are arranged at intersections of word lines WL with bit lines BLT and BLB.
[0033] The memory cell MC selected by the access control circuit 62 is connected to the corresponding bit line BLT or BLB and a potential difference is amplified by a sense amplifier 65 connected to a pair of bit lines BLT and BLB. An operation voltage of the sense amplifier 65 is supplied by a sense amplifier driving circuit 66 . As shown in FIG. 2 , at least the internal voltage VOD and the internal voltage VARY are supplied to the sense amplifier driving circuit 66 .
[0034] The internal voltage VARY corresponds to the potential difference between the bit lines BLT and BLB amplified by the sense amplifier 65 . Meanwhile, the internal voltage VOD overdrives the sense amplifier 65 during an initial activation of the sense amplifier 65 . Accordingly, VOD>VARY is established. The sense amplifier 65 is overdriven in an initial period of a sense operation to amplify the potential difference between the bit lines BLT and BLB more quickly to the internal voltage VARY.
[0035] Read data amplified by the sense amplifier 65 is supplied to a data input/output circuit 67 and then outputted to outside the semiconductor device 30 via a terminal T 5 . Further, write data inputted from the external of the semiconductor device 30 is supplied via the terminal T 5 and data input/output circuit 67 to the sense amplifier 65 and then written in the memory cell array 64 .
[0036] FIG. 3 is a circuit diagram showing an example of the internal voltage generating circuits 41 and 42 . This example shows a circuit suitable when the external voltages VDD 1 and VDD 2 are higher than the internal voltage VOD. For example, the external voltage VDD 1 is 2.0 V, the external voltage VDD 2 is 1.8 V, and the internal voltage VOD is 1.4 V.
[0037] According to the example of FIG. 3 , the internal voltage generating circuits 41 and 42 include respectively by internal voltage control units 111 and 121 that constitute differential amplifiers and voltage generation drivers 112 and 122 that output the internal voltage VOD. Specifically, the internal voltage control units 111 and 121 include respectively input transistors N 1 and N 2 , source transistors N 3 connected to sources of the input transistors N 1 and N 2 , and transistors P 1 and P 2 serially connected to the input transistors N 1 and N 2 , respectively to constitute current mirror circuits. A reference voltage VREF is supplied to gate electrodes of one input transistors N 1 and outputs (=VOD) of the voltage generation drivers 112 and 122 are returned to gate electrodes of the other input transistors N 2 .
[0038] The voltage generation drivers 112 and 122 is constituted by P-channel MOS transistors and their gate electrodes are connected to drains of the input transistors N 1 . Because of such a configuration, when a level of the internal voltage VOD serving as the output becomes lower than the reference voltage VREF, the voltage generation drivers 112 and 122 are turned on and the level of the internal voltage VOD is increased. When the level of the internal voltage VOD is increased to the reference voltage VREF, the voltage generation drivers 112 and 122 are turned off.
[0039] The control signals 41 a and 42 a are supplied respectively to the source transistors N 3 in the internal voltage control units 111 and 121 . When the control signals 41 a and 42 a become high level, the internal voltage control units 111 and 121 that constitute the differential amplifiers are activated, so that the above operations by the voltage generation drivers 112 and 122 are performed. On the other hand, when the control signals 41 a and 42 a become low level, the internal voltage control units 111 and 121 are inactivated and transistors P 3 are turned on, so that the voltage generation drivers 112 and 122 remain turned off.
[0040] FIG. 4 shows another example of the internal voltage generating circuits 41 and 42 . This example shows a circuit suitable when the external voltage VDD 1 is higher than the internal voltage VOD and the external voltage VDD 2 is lower than the internal voltage VOD. For example, the external voltage VDD 1 is 1.8 V, the external voltage VDD 2 is 1.2 V, and the internal voltage VOD is 1.4 V.
[0041] In this example, because the external voltage VDD 2 is lower than the internal voltage VOD, the internal voltage generating circuit 42 is provided with a booster circuit 123 . The booster circuit 123 increases the external voltage VDD 2 to an internal voltage VODP. The internal voltage VODP is an intermediate voltage for generating the internal voltage VOD and not particularly limited as long as it is higher than the internal voltage VOD, which is 1.9 V.
[0042] The booster circuit 123 is activated based on a boost control signal 42 b to generate the internal voltage VODP. The generated internal voltage VODP is supplied to the internal voltage control unit 121 and the voltage generation driver 122 for their operation voltage. Further, the internal voltage VODP is also supplied to a level shifter 124 and a level of the control signal 42 a is shifted by the level shifter 124 .
[0043] As described above, because the internal voltage generating circuit 42 shown in FIG. 4 includes the booster circuit 123 , the internal voltage VODP needs to be increased to a predetermined value (for example, 1.9 V) when the control signal 42 a is activated. Accordingly, the boost control signal 42 b needs to be activated at a timing at least prior to the activation of the control signal 42 a.
[0044] FIG. 5 shows still another example of the internal voltage generating circuits 41 and 42 . This example also shows a circuit suitable when the external voltage VDD 1 is higher than the internal voltage VOD and the external voltage VDD 2 is lower than the internal voltage VOD. For example, the external voltage VDD 1 is 1.8 V, the external voltage VDD 2 is 1.2 V, and the internal voltage VOD is 1.4 V.
[0045] According to this example, in addition to the circuit shown in FIG. 4 , a booster circuit 115 that increases the external voltage VDD 1 to generate an internal voltage VPP and source control circuits 116 and 126 connected respectively to the sources of the voltage generation drivers 112 and 122 are added.
[0046] The booster circuit 115 is activated based on a boost control signal 41 b to generate the internal voltage VPP. The generated internal voltage VPP is, for example, 2.7 V, and supplied to gate electrodes of N-channel MOS transistors that constitute the source control circuits 116 and 126 . When the boost control signal 41 b is activated, the source control circuits 116 and 126 are turned on. The internal voltage can thus be outputted from the voltage generation drivers 112 and 122 . When the boost control signal 41 b is not activated, the source control circuits 116 and 126 are turned off. The voltage generation drivers 112 and 122 are thus disconnected from power supplies.
[0047] The internal voltage VPP is also applied to substrates of P-channel MOS transistors that constitute the voltage generation drivers 112 and 122 . That is, a back bias higher than the external voltages VDD 1 and VDD 2 is applied to the P-channel MOS transistors that constitute the voltage generation drivers 112 and 122 . Even if generation of the internal voltage VODP by a booster circuit 123 is delayed, a substrate (N-type) and a drain (P-type) of the P-channel MOS transistor that constitute the voltage generation driver 122 are not forward biased.
[0048] Assume that a back bias of the voltage generation driver 122 is the internal voltage VODP as shown in FIG. 4 . When the internal voltage VOD is made to rise by the internal voltage generating circuit 41 before the internal voltage VODP is generated by the booster circuit 123 , the substrate (N-type) and the drain (P-type) of the P-channel MOS transistor that constitute the voltage generation driver 122 are forward biased, so that a current flows in an opposite direction. When the back bias of the voltage generation driver 122 is the internal voltage VPP (>VODP) as in this example, such current generation can be prevented, thereby reducing the consumption power.
[0049] The internal voltage VPP satisfies preferably VPP-Vt>VDD 1 or VODP, considering a threshold voltage Vt of the N-channel MOS transistors that constitute the source control circuits 116 and 126 .
[0050] FIGS. 6A to 6C are waveform diagrams of the control signals 41 a and 42 a.
[0051] In FIGS. 6A to 6C , a period that the internal circuit using the internal voltage VOD (the sense amplifier driving circuit 66 ) is activated is indicated by T 1 (from a time t 1 to a time t 2 ). In the activation period T 1 , the level of the internal voltage VOD is decreased because of charge emission. By operating the internal voltage generating circuits 41 and 42 , the internal voltage returns to its original level through a recovery period T 2 (from the time t 2 to a time t 4 or from the time t 2 to a time t 5 ).
[0052] According to the pattern shown in FIG. 6A , the control signal 41 a is activated from the time t 1 at which the activation period T 1 starts to the time t 4 at which the recovery period T 2 ends. Further, the control signal 42 a is activated from the time t 3 at which the activation period T 1 has already ended to the time t 4 . That is, this is a pattern of activating the internal voltage generating circuit 41 longer than the internal voltage generating circuit 42 . As the internal voltage generating circuits 41 and 42 are activated during a part of the recovery period T 2 in the pattern, the internal voltage VOD can be returned to its original level quickly. Thus, the pattern shown in FIG. 6A is a pattern suitable in a normal operation (a read operation and a write operation). This is because the subsequent active signal ACT can be activated at a relatively early timing in the normal operation and thus the internal voltage VOD needs to be compensated earlier.
[0053] The pattern shown in FIG. 6A is suitable when the current limit value (spec) of the external voltage VDD 1 is relatively large and the current limit value of the external voltage VDD 2 is relatively small. This pattern is also suitable when the level of the external voltage VDD 2 is lower than the internal voltage VOD and thus the booster circuit 123 needs to be used as in the examples of FIGS. 4 and 5 . This is because losses are generated by the booster circuit 123 and a conversion efficiency of the internal voltage generating circuit 42 is lower than that of the internal voltage generating circuit 41 accordingly. By using the internal voltage generating circuit 41 with higher efficiency preferentially, the total consumption power can be suppressed. In this case, it is desirable that the internal voltage generating circuit 41 is used to the extent of satisfying the current limit value of the external voltage VDD 1 and the internal voltage generating circuit 42 is used in a complementary manner.
[0054] The pattern shown in FIG. 6B is opposite to that shown in FIG. 6A . The control signal 42 a is activated from the time t 1 to the time t 4 and the control signal 41 a is activated from the time t 3 to the time t 4 . That is, this is a pattern of activating the internal voltage generating circuit 42 longer than the internal voltage generating circuit 41 . This pattern is suitable when the current limit value of the external voltage VDD 2 is relatively large and the current limit value of the external voltage VDD 1 is relatively small. In this case, it is desirable that the internal voltage generating circuit 42 is used to the extent of satisfying the current limit value of the external voltage VDD 2 and the internal voltage generating circuit 41 is used in a complementary manner.
[0055] According to the pattern shown in FIG. 6C , the control signal 41 a is activated during a period from the time t 1 at which the activation period T 1 starts to the time t 5 at which the recovery period T 2 ends and the control signal 42 a is maintained inactivated. The time t 5 is a timing later than the time t 4 shown in FIGS. 6A and 6B . The pattern shown in FIG. 6C is a pattern using only the internal voltage generating circuit 41 and providing the enlarged recovery period T 2 .
[0056] This pattern is suitable when the internal voltage VOD does not need to be compensated early like a self-refreshing operation. Naturally, the current limit value of the external voltage VDD 1 must not be exceeded. Therefore, even if the conversion efficiency of the internal voltage generating circuit 42 is lower than that of the internal voltage generating circuit 41 , the consumption power can be minimized because only the internal voltage generating circuit 41 with higher efficiency is used.
[0057] FIG. 7 is a block diagram showing an example of adding an internal voltage generating circuit 43 to the semiconductor device 30 shown in FIG. 2 .
[0058] The internal voltage generating circuit 43 generates the internal voltage VOD based on the external voltage VDD 1 and its configuration is the same as in the internal voltage generating circuit 41 shown in FIG. 3 . An operation of the internal voltage generating circuit 43 is controlled by a control signal 43 a supplied by the power supply control circuit 50 . The control signal 43 a is maintained activated unless the internal voltage generating circuit 43 is in a deep power down mode (a non-access state and generation of potentials of internal power supplies is stopped). That is, unless it is in the deep power down mode, the internal voltage generating circuit 43 continues to be operated regardless of whether the internal circuit using the internal voltage VOD (the sense amplifier driving circuit 66 ) is activated or inactivated.
[0059] By providing the internal voltage generating circuit 43 , a decrease in the internal voltage VOD during standby can be prevented. Because the internal voltage generating circuit 43 is provided to prevent a decrease in the internal voltage VOD during standby, a voltage generation driver (not shown) included in the internal voltage generating circuit 43 can be fabricated in smaller size than the ones in the internal voltage generating circuits 41 and 42 .
[0060] FIG. 8 shows a preferred layout of the internal voltage generating circuits when the memory cell array 64 is divided into four banks BANK 0 to BANKS.
[0061] As shown in FIG. 8 , when the memory cell array 64 is divided into a plurality of banks, it is preferred that each set of the internal voltage generating circuits 41 to 44 is allocated to each bank. Such a configuration allows the sets of the internal voltage generating circuits 41 to 44 to be controlled according to activation/inactivation of the respective banks. As compared to a case of providing one set of the internal voltage generating circuits 41 to 44 for the entire DRAM, the consumption current can be reduced.
[0062] FIG. 9 is a circuit diagram of the sense amplifier 65 and the sense amplifier driving circuit 66 .
[0063] The sense amplifier 65 is constituted by of P-channel MOS transistors 211 and 212 and N-channel MOS transistors 213 and 214 . The P-channel MOS transistor 211 is serially connected to the N-channel MOS transistor 213 between a power supply node a and a power supply node b, their contact is connected to one signal node c, and their gate electrodes are connected to the other signal node d. Similarly, the P-channel MOS transistor 212 is serially connected to the N-channel MOS transistor 214 between the power supply node a and the power supply node b, their contact is connected to one signal node d and their gate electrodes are connected to the other signal node c. The signal node c is connected to one bit line BLT and the signal node d is connected to the other bit line BLB.
[0064] Because of such a flip-flop structure, when a potential difference between a pair of bit lines BLT and BLB is generated while predetermined potentials are supplied to an upper drive wiring SAP and a lower drive wiring SAN, a potential of the upper drive wiring SAP is supplied to one of the bit line pair and a potential of the lower drive wiring SAN is supplied to the other of the bit line pair.
[0065] The sense amplifier driving circuit 66 is constituted by a driver 301 that supplies the internal voltage VOD to the upper drive wiring SAP, a driver 302 that supplies the internal voltage VARY to the upper drive wiring SAP, and a driver 303 that connects the lower drive wiring SAN to a ground potential. The internal voltage VARY and the internal voltage VOD are defined by the potential difference with respect to the ground potential. The drivers 301 to 303 are controlled by activation signals SEP 1 , SEP 2 , and SEN, respectively.
[0066] FIG. 10 is a circuit diagram of the power supply control circuit 50 .
[0067] As shown in FIG. 10 , the power supply control circuit 50 includes a timing circuit 51 that receives the active signal ACT and the refresh signal REF to generate an activation signal SEN and a delay circuit 52 that generates a delay signal SEND obtained by delaying the activation signal SEN. The activation signal SEN and the delay signal SEND are inputted to an OR gate 53 and its OR output is used as the control signal 41 a. The delay signal SEND and the active signal ACT are inputted to an AND gate 54 and its AND output is used as the control signal 42 a.
[0068] Because of such a configuration, when the active signal ACT is activated, the control signal 41 a is activated to high level during a fixed period and the control signal 42 a is activated to high level during a fixed period at the end of activation period of the control signal 41 a as shown in FIG. 6A . Meanwhile, when the refresh signal REF is activated, the control signal 41 a is activated to high level during a fixed period but the control signal 42 a is maintained inactivated as shown in FIG. 6C .
[0069] FIG. 11 is a waveform diagram for explaining the sense operation of the semiconductor device 30 according to the present embodiment.
[0070] As shown in FIG. 11 , when the sense operation starts at a time t 11 , the activation signals SEP 1 and SEN are activated. As described above, the activation signal SEP 1 controls the driver 301 and the activation signal SEN controls the driver 303 . The internal voltage VOD is thus supplied between the power supply nodes a and b of the sense amplifier 65 . The internal voltage VOD higher than the internal voltage VARY is used in the initial period of the sense operation, because the potential difference between the bit lines BLT and BLB is amplified more quickly by overdrive.
[0071] Thereafter, the activation signal SEP 1 is inactivated at a time t 12 and overdrive ends. The activation signal SEP 2 is then activated and thus the internal voltage VARY is supplied between the power supply nodes a and b of the sense amplifier 65 . The activation signal SEP 2 is inactivated at a time t 15 and the activation signal SEN is inactivated at a time t 14 .
[0072] Meanwhile, as the delay signal SEND which is activated from a time t 13 to a time t 16 is generated by the power supply control circuit 50 shown in FIG. 10 , the control signal 41 a is activated from the time t 11 to the time t 16 . The internal voltage generating circuit 41 is activated during this period and the reduced internal voltage VOD is compensated.
[0073] The waveform of the control signal 42 a varies depending on whether the sense operation is due to the active signal ACT or the refresh signal REF. When the sense operation is due to the active signal ( 42 a (ACT)), the control signal 42 a is activated from the time t 13 to the time t 16 by the power supply control circuit 50 shown in FIG. 10 . That is, the internal voltage generating circuit 42 is activated during this period and the reduced internal voltage VOD is compensated. As the internal voltage VOD reduced by the sense operation is compensated by the two internal voltage generating circuits 41 and 42 (three internal voltage generating circuits when the internal voltage generating circuit 43 is added), the voltage is recovered quickly.
[0074] When the sense operation is due to the refresh signal ( 42 a (REF)), the control signal 42 a is maintained inactivated. The internal voltage generating circuit 42 is not activated and the internal voltage VOD reduced by the sense operation is compensated by only one internal voltage generating circuit 41 (two internal voltage generating circuits when the internal voltage generating circuit 43 is added). The voltage is thus recovered relatively gently.
[0075] As described above, according to the present embodiment, when the sense operation is performed due to the active signal ACT, that is, in the normal read or write operation, the internal voltage VOD is driven by the internal voltage generating circuits 41 and 42 . Meanwhile, when the sense operation is performed due to the refresh signal REF, the internal voltage VOD is driven only by the internal voltage generating circuit 41 . That is, in a normal operation that the internal voltage VOD reduced by the sense operation needs to be recovered quickly, the compensation is performed by the two internal voltage generating circuits 41 and 42 . In a self-refreshing operation that the internal voltage VOD reduced by the sense operation does not need to be recovered quickly, the compensation is performed only by the internal voltage generating circuit 41 . With this arrangement, the consumption power during the self-refreshing operation can thus be reduced while successive high speed accesses can be realized.
[0076] Furthermore, as the compensation is performed by the internal voltage generating circuits 41 and 42 using different external voltages VDD 1 and VDD 2 in the normal operation, the load is not centralized only on a particular external power supply.
[0077] It is apparent that the present invention is not limited to the above embodiments, but may be modified and changed without departing from the scope and spirit of the invention.
[0078] For example, in the above embodiment, while the internal voltage generating circuits 41 and 42 that generate the internal voltage VOD by using different external voltages VDD 1 and VDD 2 are selectively activated, three or more internal voltage generating circuits that use three or more external voltages with different levels can be selectively activated.
[0079] In the above embodiment, while the operation of the internal voltage generating circuits 41 and 42 during the activation of the active signal ACT is different from the operation during the activation of the refresh signal REF, the operation of the internal voltage generating circuits 41 and 42 can be controlled according to other signals (for example, a pre-charge signal).
[0080] Further, the activation period of the internal voltage generating circuits 41 and 42 does not need to be fixed, and can be varied freely by changing, for example, the delay amount of the delay circuit 52 . | To provide a first internal voltage generating circuit that generates an internal voltage based on a first external voltage and a second internal voltage generating circuit that generates the internal voltage based on a second external voltage. The semiconductor device generates an internal voltage from a plurality of the first and second external voltages. These external voltages can be utilized efficiently depending on a load state. Therefore, even in a semiconductor device with greatly varying consumption power, it is not necessary to enlarge only a particular power supply device. | 8 |
The present disclosure relates to the subject matter disclosed in German application No. 101 28 918.9 of Jun. 15, 2001 and international application PCT/EP 02/05652 of May 23, 2002, which are incorporated herein by reference in their entirety and for all purposes.
BACKGROUND OF THE INVENTION
The invention relates to an implant for fixing adjacent bone plates, in particular cranial bone plates, having an inner abutment element by means of which a separation gap between the bone plates can be overlapped at a bone plate inner side and having an outer abutment element for overlapping the separation gap at a bone plate outer side lying opposite the bone plate inner side.
For brain surgery a craniotomy has to be performed in order to gain access to the brain tissue that is to be operated on. For this purpose, one or more bone plates are sawn out of the skull. On completion of the brain surgery these bone plates have to be reinserted and fixed to the bone plates of the rest of the skull. For this purpose, suitable implants are provided, which remain in the body of the patient.
SUMMARY OF THE INVENTION
In accordance with the present invention, an implant for fixing adjacent bone plates is provided, which is easy for the surgeon to use and by means of which the bone plates may be securely fixed.
This is achieved in accordance with the invention in that at least one tension band is guided displaceably through the outer abutment element, by means of which, when a tensile stress is exerted, the inner abutment element and the outer abutment element are mutually braceable, and that the at least one tension band is fixable to the outer abutment element.
Through the tightening of a tension band the inner abutment element and the outer abutment element may be moved towards one another and mutually braced so that the adjacent bone plates are fixed to one another. This tensioned position in turn may be secured by fixing the tension band to the outer abutment element. The bracing may therefore be effected easily by the surgeon without the requirement for an additional application instrument.
A tension band is easy for the surgeon to manipulate because it has a sufficiently large width for grasping and exerting tension.
A tension band moreover provides enough surface area to be able to effect fixing to the outer abutment element. In particular, for securing the fixed position of the bone plates hook elements are provided, which may penetrate the tension band and therefore secure this fixed position.
Furthermore, the implant according to the invention is also easy to manufacture since the inner abutment element and the outer abutment element may be manufactured separately from the tension band and the connection between tension band and abutment elements may easily be produced by threading the former through the latter.
The implant according to the invention is moreover insertable in an advantageous manner: during insertion of a bone plate into a cranial recess the inner abutment element may be held by means of the tension band until the desired relative positioning of the bone plates is achieved. It is then possible afterwards to guide the outer abutment element by means of the tension band and hence effect the bracing.
A tension band may in said case, depending on the application, be manufactured from an absorbable or non-absorbable material. Suitable absorbable materials are, in particular, synthetic materials or organic materials. Suitable non-absorbable materials are plastics materials such as PEEK or also metal materials such an titanium or other biologically compatible materials.
It is quite particularly advantageous when the width of the at least one tension band is greater than its height and in particular is substantially greater, e.g. at least five times greater. This then provides a corresponding surface area, which is easier for a surgeon to grasp and which allows easy fixing of the tension band to the outer abutment element by means of hook elements.
In said case, in order further to facilitate handling and obtain a secure fixing to the outer abutment element, the width of the at least one tension band is in the region of between 25% and 75% of a width dimension of an abutment element. In particular, in said case the width is in the region of ca. half of this width dimension, which in the case of a round disk-shaped abutment element is the diameter.
In particular, it is provided that the at least one tension band is of a flexibly bendable design so as to allow the two abutment elements to be drawn towards one another and hence braced relative to one another.
It is provided that the at least one tension band is held on the inner abutment element in order during the bracing to provide a fixed point, i.e. ensure that the tension band no longer moves relative to the inner abutment element.
It may then in principle be provided that the at least one tension band is fastened to the inner abutment element, i.e. is fixed invariably with regard to its holding point thereon.
It is however quite particularly advantageous when a tension band is passed through the inner abutment element and in said case the tension band is held on the inner abutment element by means of a tension band bend. Thus, the tension band may be fixed on the inner abutment element, wherein however said fixing is variable. Thus, on the one hand, manufacture is facilitated and, on the other hand, because of the holding by means of a tension band bend a high degree of certainty that the inner abutment element and the tension band will not detach from one another is achieved.
From the point of view of manufacture, it is advantageous when the inner abutment element has two spaced-apart openings for passing the tension band through. Between the openings a kind of bridge is then formed, which holds, i.e. forms a bearing surface for, the tension band bend.
In said case, the openings are advantageously so disposed and designed, i.e. the bridge element is also correspondingly so disposed and designed, that a first tension band region and a second tension band region, between which a tension band bend is formed, during penetration of the separation gap are alignable substantially parallel to one another. This prevents the tension band bends from possibly exerting transverse forces upon the bone plates and, when tension is exerted upon the at least one tension band, possibly shifting the bone plates towards one another.
In order to provide a uniform bearing surface for the adjacent bone plates, the openings are advantageously disposed substantially mirror-symmetrically relative to a center of the inner abutment element.
It is in said case advantageous when the spacing of the openings is less than ca. an eighth of a width dimension of the inner abutment element. In the case of a circular abutment element, this width dimension is the diameter. It is thereby possible to ensure that the separation gap, through which the tension band has to be passed, does not become too large and, on the other hand, achieve parallel guidance of appropriate tension band regions.
In said case, edges of the openings are advantageously rounded off to prevent damage to the tension band.
It is further advantageous when the outer abutment element has one or more openings, through which in each case one longitudinal end of a tension band is passable. Thus, by means of the at least one tension band the outer abutment element may be fixed relative to the inner abutment element and so, in turn, adjacent bone plates may be fixed between the two abutment elements.
In order by tightening the tension band to be able to effect a bracing of the two abutment elements and in addition move the outer abutment element relative to the inner abutment element, an opening has a deflection edge for deflecting a tension band, so that a tensile force is exertable upon the tension band transversely relative to a direction of spacing between inner abutment element and outer abutment element. In particular, in said case the deflection edge is rounded off in order to guarantee good guidance of the tension band in the opening and, on the other hand, prevent damage to the tension band.
Advantageously in said case the opening or openings are disposed and designed in such a way that the at least one tension band is positioned substantially at right angles to the abutment element in the separation gap in order thereby to prevent the tension band from exerting transverse forces upon the bone plates and to be able to keep the size of the separation gap small.
A fixation of the bone plates between the abutment elements is easily achievable when a tensile force with a transverse component in a first direction is exertable upon a first tension band end and a tensile force with a transverse component in an opposite direction is exertable upon a second tension band end. By a relative pulling of the two tension band ends apart from one another, the outer abutment element is then displaced in the direction of the inner abutment element and a bracing and hence fixation of the bone plates between the two abutment elements is effected.
An implant according to the invention may easily be manufactured when the first tension band end and the second tension band end are formed on the same tension band, i.e. when the tension band is looped through the inner abutment element and then the respective ends are conveyed in opposite directions.
The fixation of the bone plates may easily be secured when the at least one tension band may be hooked in relative to the outer abutment element. The tension band provides a large surface area for the engagement and in particular for the penetration of hook elements in order thereby to enable the fixing of the tension band relative to the outer abutment element.
In particular, it is in said case advantageous when a hook element has an inclined flank and a steep flank, wherein the steep flank is arranged facing a pulling end of the at least one tension band. In said case, the steep flank is in particular designed in such a way that, when the tension band is hooked in, the steep flank is substantially at right angles to the tension band. A hook element then has a substantially triangular cross section, wherein the steep flank is the one at a steeper angles relative to a vertical direction of the triangle. Given a corresponding arrangement of the steep flank facing the pulling end, it is guaranteed that during the hooking-in operation the tension is not reduced, since hooking-in of the hook-connection face of a hook element is effected in a region of the tension band situated closer to the inner abutment element, on which the tension band is held, and so the tensioning force is maintained while the hooking-in operation is effected. On the other hand, however, it is thereby also ensured that the forces acting upon the tension band do not increase, with the result that e.g. a relative positioning of the bone plates desired by the surgeon is not destroyed by increased forces during the hooking-in operation.
In a variant of a form of construction the hook element or elements are disposed on the outer abutment element. The surgeon may then easily effect the fixed position of the bone plates by hooking-in of the tension band on the outer abutment element. In particular, in said case a row of spaced-apart hook elements is provided for effecting a fixation over a large surface area.
It may in said case be provided that the hook element or elements are disposed on an outer surface of the outer abutment element. In particular, in said case hook tips are directed away from an outer surface of the outer abutment element.
It may alternatively or additionally be provided that the hook element or elements are disposed in an opening for passing the at least one tension band through. In this variant, fixing of the tension band is effected in the opening. Hook tips are then orientated transversely of a direction of spacing between inner abutment element and outer abutment element.
In a further form of construction a fixation cap is provided for mounting on the outer abutment element, wherein the tension band is fixable between the outer abutment element and the fixation cap. It is then possible to effect fixation of the bone plates and secure this position by mounting the fixation cap.
It is in said case quite particularly advantageous when the fixation cap comprises a bridge element, which is insertable into the separation gap. This bridge element then effects an additional fixation in the separation gap and, on the other hand, the separation gap may be filled by the bridge element.
The bridge element is advantageously insertable between opposite tension band regions into the separation gap, thereby achieving an additional securing of the tensioned position of the tension band.
In a variant of a form of construction there are formed on the bridge element transverse tabs, which are elastically movable at right angles to the direction of spacing between inner abutment element and outer abutment element.
Thus, in the inserted state of the bridge element, when this is suitably adapted to the outer abutment element, an elastic force may be exerted by the bridge element upon the abutment element, which effects an additional fixing of the fixation cap on the outer abutment element, so that in turn a good securing of the fixation of the bone plates may be achieved.
In order to fix the tension band between the outer abutment element and the fixation cap, the fixation cap and/or the outer abutment element is provided with one or more hook elements and the outer abutment element and/or the fixation cap is provided with corresponding openings for receiving the hook element or elements. It may thereby be guaranteed that the hook elements penetrate and hence securely hold the tension band. The openings then ensure that the hook elements, which project relative to the tension band, are received. Furthermore, an additional fixing may be achieved by the engagement of the hook elements into the openings.
The following description of preferred forms of construction is used in connection with the drawings to explain the invention in detail.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a side sectional view of a first embodiment of an implant according to the invention for fixing adjacent bone plates, wherein a fixed position is shown;
FIG. 2 a sectional view in direction A of the implant according to FIG. 1 ;
FIG. 3 a variant of the embodiment according to FIGS. 1 and 2 in a sectional view in the direction A;
FIG. 4 a sectional view of a second embodiment of an implant according to the invention for fixing adjacent bone plates;
FIG. 5 a sectional view of a third embodiment of an implant according to the invention for fixing adjacent bone plates and
FIG. 6 a plan view in direction B of the implant according to FIG. 5 .
DETAILED DESCRIPTION OF THE INVENTION
By means of an implant according to the invention adjacent bone plates 10 , 12 may be fixed. For example, for brain surgery the cranium is opened by removing one or more pieces of bone. At the end of surgery the corresponding bone pieces are reinserted, for which purpose the adjacent bone plates 10 and 12 then have to be positioned relative to one another and fixed in an appropriate final position. In said case, between the bone plates 10 and 12 a separation gap 14 is formed, through which connecting means 16 for the connection between an inner abutment element 18 and an outer abutment element 20 may be passed. If, for example, the bone plates 10 and 12 are cranial bone plates, then the inner abutment element 18 is positioned on bone plate inner sides 22 facing the cranium interior and the outer abutment element 20 is positioned on an opposite bone plate outer side 24 .
In the first embodiment of an implant according to the invention for fixing adjacent bone plates 10 , 12 , which is illustrated in FIG. 1 and denoted there as a whole by 26 , the inner abutment element 18 is of a disk-shaped design, wherein it has in particular a circular cross section. It is made of a plastics material well-tolerated by the body, an absorbable plastics material or a metal. An outer surface 28 of the inner abutment element is curved in a convex manner. An opposite surface 30 to this outer surface 28 is provided with a toothed wheel ring 32 , which is used for an improved grip on the bone plates 10 and 12 .
By means of the inner abutment element 18 the separation gap 14 is overlappable, so that the toothed wheel ring 32 lies in a sub-region 34 a against the bone plate 10 and in an, in particular, opposite sub-region 34 b against the bone plate 12 .
Outside of the toothed wheel ring 32 the surface 30 is set back relative to tooth tips.
Formed in the inner abutment element 18 in a central region are two spaced-apart slot-shaped through-openings 36 , 38 , which extend between the surfaces 30 and 28 . They are separated by a bridge element 40 . This bridge element 40 has rounded-off edges 42 in particular facing the outer surface 28 .
The outer abutment element 20 is likewise of a disk-shaped design and has in particular a circular cross section, wherein the outer dimensions of the outer abutment element 20 substantially correspond to those of the inner abutment element 18 . It is, like the inner abutment element 18 , made of a plastics material well-tolerated by the body, an absorbable plastics material or metal. It likewise has a convex outer surface 44 and an opposite surface 46 , which is provided with a toothed wheel ring 48 corresponding to the toothed wheel ring 32 of the inner abutment element 18 .
Formed in the inner abutment element in a central region is a slot-shaped through-opening 50 , through which the connecting means 16 are passable.
In the outer surface 44 there is provided adjacent to the opening 50 a square recess 52 , which is used to receive a fixation cap 54 . A bridge element 56 is in said case disposed in a central region and, in particular, integrally on the fixation cap 54 and is of a wedge-shaped design at its front end 58 . This bridge element 56 may be inserted into and hence at least partially fill the separation gap 14 between the bone plates 10 and 12 and the connecting means 16 may be fixed relative to the separation gap 14 in the manner described in greater detail below.
The fixation cap 54 has, symmetrically relative to the bridge element 56 , opposing hook elements 60 , 62 , which may engage into corresponding through-openings 64 , 66 of the outer abutment element 20 . A hook element 60 , 62 in said case has a steep flank 68 and an inclined flank 70 , so that a hook element 60 , 62 is of a triangular design. Thus, once the fixation cap 54 has been inserted into the recess 52 , a tip 72 of a hook element 60 , 62 points in the direction from the outer surface 44 to the surface 46 , wherein the inclined flank 70 faces the central region of the outer abutment element 20 , i.e. in particular faces the bridge element 56 , while the steep flank 68 is disposed remote from this central region.
The connecting means 16 are formed by a tension band 74 , which is elastically bendable. This tension band may be made of an absorbable or non-absorbable material. At the inner abutment element 18 the tension band is held in the openings 36 , 38 on the bridge element 40 by means of a tension band bend 76 , which is adjoined in each case by a first tension band region 78 and a second tension band region 80 , which penetrate the separation gap 14 . The first tension band region 78 is deflected at the opening 50 , which for this purpose has in particular rounded-off edges, and extends substantially parallel to the outer surface 44 of the outer abutment element 20 . In a corresponding manner the second tension band region 80 is likewise deflected and likewise extends parallel to the outer surface 44 of the outer abutment element 20 . Corresponding ends of the tension band 74 , which are associated with the first tension band region 78 and the second tension band region 80 , are in said case situated remote from one another and the bridge element 56 is situated between these ends.
In the separation gap 14 the two tension band regions 78 and 80 are aligned substantially parallel to one another.
The tension band 74 is fixed relative to the inner abutment element 18 and the outer abutment element 20 in that the hook elements 60 , 62 hook into the tension band 74 and these hook elements 60 , 62 then engage further into the associated openings 64 , 66 of the outer abutment element 20 . By said means a fixation of adjacent bone plates 10 , 12 by means of the implant 26 may be achieved.
The implant 26 according to the invention operates in the following manner:
The tension band 74 is looped by means of the through-openings 36 and 38 through the inner abutment element 18 . The tension band in said case has a width B which is considerably greater than its height H. It is moreover looped through the outer abutment element 20 through the opening 50 thereof, in which case a surgeon may then grasp the respective ends of the tension band 74 .
The bone plates 10 and 12 and the abutment elements 18 and 20 are positioned relative to one another in such a way that, firstly, the tension band 74 with its first tension band region 78 and its second tension band region 80 penetrates the separation gap 14 , the inner abutment element 18 lies against the bone plate inner side 22 and overlaps the separation gap 14 , and the outer abutment element 20 lies against the bone plate outer side 24 and likewise overlaps the separation gap 14 . A surgeon then exerts tension upon each of the two ends of the tension band 74 , which are associated in each case with the tension band regions 78 and 80 , or holds one end fast and exerts tension upon the other end. In particular, for this purpose the tension band 74 is in each case folded over and conveyed parallel to the outer abutment element 20 , so that the surgeon may exert upon the respective ends tensile forces in opposing directions in opposite ends. By virtue of such a tightening of the band the abutment elements 18 and 20 are drawn towards one another so as to achieve a secure fixation of the bone plates 10 and 12 between the abutment elements 18 and 20 . The fixation cap 54 is then inserted into the recess 52 , wherein the bridge element 56 engages into the separation gap 14 . Thus, the tension band 74 is fixed in the separation gap 14 and the separation gap 14 is also at least partially filled by the bridge element 56 .
During mounting of the fixation cap 54 the hook elements 60 , 62 simultaneously engage into the tension band 74 and form a hooked connection therewith. The hook elements 60 and 62 engage into the associated openings 64 and 66 . Consequently, the tension band 74 is fixed to the outer abutment element 20 and so, in turn, the fixed position of the bone plates 10 and 12 between the outer abutment element 20 and the inner abutment element 18 is secured.
The hook elements 60 , 62 penetrate the tension band 74 , i.e. the steep flank 68 has a height that is greater than the height H of the tension band 74 . The designing of a hook element 60 , 62 with the arrangement of the inclined flank 70 facing the opening 50 and the steep flank 68 facing the end of the tension band 74 in said case guarantees the forming of a hooked connection with simultaneous securing of the tensioned position.
The width B of the tension band is in the region of between ca. 25% and 75% of the diameter of the outer abutment element 20 and/or inner abutment element 18 . Firstly, this makes it easy for the surgeon to grasp the tension band. Secondly, a large surface are is provided for hooked connections by means of the hook elements 60 and 62 .
It may also be provided that, instead of a hook element 60 and/or 62 , a row of hook elements is provided. It may moreover alternatively be provided that the hook elements are formed on the outer abutment element 20 and the fixation cap 54 then has corresponding openings.
A variant of the first embodiment 26 , which is illustrated in FIG. 3 , differs essentially in a different design of a fixation cap 82 . Otherwise, the corresponding implant is designed and operates in an identical manner to that described above. Identical elements of the implant according to FIG. 3 therefore bear the same reference characters as for the implant 26 .
The fixation cap 82 comprises a round cover disk 84 , on which a bridge element 86 is integrally formed. This bridge element at its front end 88 is of a wedge-shaped design.
On the bridge element 86 opposite-lying transverse tabs 90 , 92 are formed by respective slot-shaped recesses 94 , 96 , which extend substantially at right angles to the cover disk 84 . On ends facing the cover disk 84 the transverse tabs 90 , 92 are provided with retaining heads 98 , 100 .
By virtue of the recesses 94 and 96 the transverse tabs 90 and 92 respectively are movable transversely relative to the surface normal of the cover disk 84 , i.e. in the region of the transverse tabs 90 , 92 the width of the bridge element 86 may be reduced. This reduction of the width requires an expenditure of force for elastic deformation of the bridge element 86 . The bridge element 86 may therefore be pushed through the opening 50 into the separation gap 14 , wherein however the transverse tabs 90 , 92 are bent elastically in the direction of the centrical axis of the cover disk 84 . Once the cover disk 84 has been mounted and hooked in the tension band 74 , the transverse tabs 90 , 92 in the opening 50 then in turn exert a force upon the outer abutment element 20 , wherein the retaining heads 98 , 100 ensure reliable retention. The bridge element 86 and hence the fixation cap 82 are therefore additionally, besides the engagement of the hook elements 60 , 62 into the associated openings 64 , 66 , braced with the outer abutment element 20 .
In a second embodiment, which is denoted as a whole by 102 in FIG. 4 , the inner abutment element 18 is in principle of an identical construction to that described above. Identical reference characters are therefore used.
In the implant 102 an outer abutment element 104 is provided, which has a convex outer surface 106 and, remote therefrom, a surface 108 for resting against a bone plate outer side 24 . This surface 108 is provided with a toothed wheel ring 110 .
In a central region the outer abutment element 104 has a slot-shaped through-opening 112 , through which the tension band 74 is passable. By means of the opening 112 deflection edges 114 , 116 are formed, which are in particular rounded off, for changing the direction of the tension band from a direction substantially parallel to the separation gap 14 to a direction at right angles thereto. By exerting tension upon the respective ends 118 and 120 of the tension band 74 and/or by holding one end fast and exerting tension upon the other end, i.e. by tightening the tension band 74 , the inner abutment element 18 and the outer abutment element 104 are drawn towards one another and the bone plates 10 and 12 situated therebetween may be securely fixed.
On its outer surface 106 the outer abutment element 104 has hook elements 122 , 124 , which are disposed in particular symmetrically relative to the opening 112 and are each associated with one end 118 , 120 of the tension band 74 . A steep flank 126 of a hook element 122 and/or 124 is in said case directed away from the opening 112 , while an inclined flank 128 faces the opening 112 .
After tightening of the tension band, the tension band may then be hooked into the respective hook elements 122 , 124 in order thereby to secure the fixation of the bone plates 10 and 12 by means of the abutment elements 18 and 104 .
In a third embodiment, which is denoted as a whole by 130 in FIGS. 5 and 6 , the inner abutment element 18 is likewise in principle of an identical construction to that described above. An outer abutment element 132 has a convex outer surface 134 . Remote from said surface, a surface 136 of the outer abutment element 132 is provided with a toothed wheel ring 138 in the manner described above.
In the outer abutment element 132 two spaced-apart slot-shaped through-openings 140 and 142 are formed in a central region and separated by a bridge element 144 . The tension band 74 is passed through these openings 140 and 142 .
On the outer abutment element 132 a row of hook elements 146 , 148 is formed in the openings 140 and 142 , in each case opposite the bridge element 144 . A hook 150 of such a row in said case has a steep flank facing the outer surface 134 of the outer abutment element 132 and an inclined flank arranged facing the surface 136 .
Through the openings 140 and 142 respective ends of the tension band 74 are threaded, and by tightening the tension band the inner abutment element 18 and the outer abutment element 132 may be drawn towards one another and so the bone plates 10 and 12 may be fixed relative to one another by means of the abutment elements 18 and 132 . This fixed position may be secured by hooking the tension band into the hooks 150 of the hook rows 146 and 148 .
Given the use according to the invention of a tension band, no application instrument is required for fixing the bone plates 10 , 12 between inner and outer abutment element: by tightening the tension band 74 a surgeon may draw the abutment elements towards one another and hence achieve a secure fixation of the bone plates 10 and 12 relative to one another. This fixed position is then secured by hooking-in of the tension band 74 , wherein the corresponding hook elements penetrate the structure of the tension band 74 . In said case, depending on the application the tension band 74 may be made of an absorbable material or a non-absorbable material. | In order to provide an implant for fixing adjacent bone plates, in particular cranial bone plates, which has an inner abutment element by means of which a separation gap between the bone plates can be overlapped at a bone plate inner side and has an outer abutment element for overlapping the separation gap at a bone plate outer side lying opposite the bone plate inner side and which is easy for a surgeon to use and by means of which the bone plates may be securely fixed, it is proposed that at least one tension band is guided displaceably through the outer abutment element, by means of which, when a tensile stress is exerted, the inner abutment element and the outer abutment element are mutually braceable, and that the at least one tension band is fixable on the outer abutment element. | 0 |
DESCRIPTION OF THE PRIOR ART
Among the more widely practiced methods for the recovery of petroleum from a subterranean formation is water-flooding. In this method, flood water is injected into the formation via one or more injection wells, which water displaces the petroleum in the formation toward one or more production wells. More recently, improvements in water-flooding methods have included the use of water-soluble polymers whereby the viscosity of the flood water is increased. The "thickened" water results in a more favorable mobility ratio and leads to improved oil recovery. There are only a few polymers which are suitable for the purpose and can be used economically. At small concentrations these polymers are effective in increasing the viscosity of the water in the desired manner and are also resistant to the conditions of the formation. Among the suitable polymers are the polyacrylamides, which may be partially hydrolyzed, the polysaccharides and the cellulose ethers, such as hydroxyethylcellulose. The polyacrylamides are long-chain polymers of acrylamide with the general formula
[--CH.sub.2 --CH(CONH.sub.2)--].sub.n
wherein n is about 50,000 or over. The molecular weight is three to six million. With partially hydrolyzed polyacrylamides, some of the amide groups--CONH 2 --are converted by saponification reaction into carboxylate groups--COO - --. Particularly favorable for polymer flooding are the partially hydrolyzed polyacrylamides, that are hydrolyzed to 10-60%, preferably in the 20-35% range. Partially hydrolyzed polyacrylamides of high molecular weight (1 to 10 million) are relatively inexpensive. The desired viscosity increase for small concentrations, of about 0.3-1 g/l, however is achievable only in solutions in practically salt-free or fresh water. Solutions of 0.5 g/l of partially hydrolyzed polyacrylamides in soft water at shear gradients between 1 and 10 s -1 , which are representative for flowing in deposits, have a viscosity that is 10 to 40 times higher than that of water. In order to achieve this viscosity increase in salt water there are required, on the other hand, concentrations of from 1.5 to 4 g/l of the same polymer, with the risk of the polymer being precipitated in the form of water-insoluble salts, when the portion of bivalent ions in the total salinity is high. The precipitation of polyacrylamide can be eliminated and a reduction of the salt-sensitivity can thus be achieved by decreasing the degree of hydrolysis to below 15%, in extreme cases to a hydrolysis rate of 0, in the case of non-ion products. However, concentrations of from 1.5 to 4 g/l are still required to increase the viscosity in salt water.
Polysaccharides are linearly condensed saccharides with up to several thousand monosaccharide units, which are produced for the present use by means of Xanthomonas campestris or Fungus Sclerocium. The molecular weight suitable for polymer flooding is in the range of 500,000 to several million, preferably 1 million and over. Polysaccharides of high molecular weight are less salt-sensitive, but more expensive than polyacrylamides and less viscosity-productive. Concentrations of about 0.75 g/l are required in order to achieve a 10 to 20 fold increase in viscosity. Per cubic meter of polymer solution, about three times the expenditure is to be incurred than for partially hydrolyzed polyacrylamides in soft water.
Water-soluble cellulose ethers, in particular hydroxyalkylcellulose with low alkyl groups, such as C 1-4 , in particular hydroxy ethyl cellulose, are also suitable for polymer flooding wherein the molecular weight is 300,000 to 600,000 and over. Hydroxyethylcellulose is also little salt-sensitive, however, as other cellulose derivatives also, it can be made only with limited molecular weight, less than 500,000. Therefore, for the desired increase in viscosity, concentrations of about 3 g/l are necessary.
Most petroleum formations contain highly-saline waters, which contain, in addition to the alkali chlorides, considerable concentrations of alkaline salts and even small concentrations of borates, sulphides and iron ions that are particularly injurious to all polymers. It is not possible to dissolve one of the named polymers in such waters without obtaining a decomposition or flocculation of the polymer--in many cases only after some time and/or at an increased temperature. It is also known, and in fact especially when using surfactants to increase the oil yield, to optimize the conditions in the formation by means of a preflood operation by the injection of water of suitable salinity for the chemicals solution to be used. It is also known to preflood with soft water or water of a low saline content in order to be able to use the relatively inexpensive aqueous solution of partially hydrolyzed polyacrylamide. In tests on sand packs it has been shown that with homogeneous packing and linear flow some 25% of the pore volume passed through is necessary to reduce the salinity of water to 1% of the original value, as a result of which the damaging of the polyacrylamide would be reduced to a tolerable extent. In formation models with radial flow and nonhomogenous flowing capacity considerably greater volumes are required for preliminary flooding. For use in the field this means that it would be necessary for some years to effect a preliminary flooding with soft water, and thus the start of the polymer flooding and thereby the additional oil recovery would be delayed.
In a formation having a highly saline aqueous saturation it is also possible to inject salt-insensitive polymers, such as polysaccharide, non-hydrolyzed polyacrylamide or polyacrylamide, hydrolyzed to maximum 15%, or hydroxyethylcellulose. On mixing with salt water of the formation, viscosity reduces simply correspondingly to dilution, differently from when partially hydrolyzed polyacrylamides are used. These polymers suffer, if at all, only limited damage of viscosity by salt-water. Because of the high cost however, the use of polymers for the entire flooding project, mostly volumes of 20 to 40% of the pore volume to be covered, is not a very economical proposition.
It is thus an object of the present invention to overcome the problems associated with polymer flooding by the use of a first slug of a salt-insensitive polymer prior to undertaking a polymer flood with a partially hydrolyzed polyacrylamide.
FIELD OF THE INVENTION
This invention relates to a process for recovering petroleum from underground formations by polymer flooding wherein a slug of an aqueous solution of a salt-insensitive polymer is injected prior to undertaking the polymer flood.
DESCRIPTION OF THE PREFERRED EMBODIMENT
It has now been found that it is possible to replace the preliminary flooding with soft water by a very small volume of these salt-insensitive polymers in soft water, in order to protect a subsequently flooded solution of partially hydrolyzed polyacrylamide in soft water from damage by the formation water.
In surprising manner the salt content at the front of the salt-insensitive polymer solution is reduced so quickly to minimum values that only a small percentage of the pore volume of salt-insensitive polymer solution is required to obtain the same reduction of salt content as with large volumes of soft water. Besides the polysaccharide solution this effect can be obtained with solutions of other salt-insensitive polymers in soft water such as with hydroxyalkyl ethers of cellulose, particularly with hydroxyethylcellulose or nonhydrolyzed polyacrylamide, or polyacrylamide hydrolyzed to maximum 15%.
The volume of the injected slug of the aqueous solution of the salt-insensitive polymer should be in the range of 5 to 15%, preferably 7 to 10%, of the pore volume of the formation to be flooded. Advantageously, the subsequent polymer flooding is carried out with a volume corresponding to 10 to 40% of the formation pore volume with a partially hydrolyzed polyacrylamide.
Solutions of such high molecular materials are not genuine liquids in the rheological sense. The viscosity depends on the velocity gradient. The flow characteristics of this pseudo plastic solution follows the exponential law:
γ.sup.η =τ/η.sub.1 (1)
γ=shear rate (s -1 )
τ=shear strength (dyne/cm 2 )
η and η 1 are constants, η 1 is the apparent viscosity at a shear rate of 1 s -1 . The exponent, n, is smaller than 1. For genuine liquids n=1. The concentration of the polymer solution is to be adjusted in such a way that its apparent viscosity under deposit conditions reaches a high multiple of the viscosity of the water, preferably 5 to 30 times.
The improvement in polymer flooding was demonstrated in the following laboratory tests. A plexiglass model, geometrically similar to a formation deposit, was filled with sand, and impregnated with oil and salt water in a manner corresponding to the fluid ratios prevailing in formation.
In the first test, the model was waterflooded, with soft water in the known manner of the art, using an amount of about 37% of the pore volume. The waterflood was followed by the injection of an aqueous solution of soft water containing 0.5 kg/m 3 of partially hydrolyzed polyacrylamide. After an amount of about 20% of the pore volume had been injected, the concentration of the polyacrylamide was linearly reduced from 5 kg/m 3 to 0 kg/m 3 during continued injection of an additional 20% pore volume. The average molecular weight of the partially hydrolyzed polyacrylamide was about 4 million.
In the second test, first of all, without a preliminary waterflooding with soft water, a slug of 7% of the pore volume of a solution of 0.75/m 3 kg polysaccharide having an average molecular weight of about 12 million, was injected, followed by a slug of 15% of the pore volume of 0.5 kg/m 3 of the partially hydrolyzed polyacrylamide. Thereafter, a slug of 20% pore volume containing the partially hydrolyzed polyacrylamide in a linearly decreasing concentration as described above, was injected.
Although the amount of polymer used and the costs were in the second instance higher than in the first, an economic advantage, calculated on a high level in terms of field conditions, was obtained. It was 50% higher than with the comparative process in the first test. This substantial and surprising advance obtained according to the invention is conditioned by savings in waterflooding costs and also substantially through the oil yield coming about 30 months earlier. | An improved polymer flood process for the recovery of petroleum from a subterranean formation wherein a slug of a fresh water aqueous solution of a salt-insensitive polymer is injected into the formation prior to the undertaking of the polymer flood using a fresh water solution containing a partially hydrolyzed polyacrylamide. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention.
The present invention relates to anthropomorphological dummies and more particularly to a hydro-pneumatic system situated in the trunk of an anthropomorphological dummy to simulate the balance and the thoracic-abdominal pressure compensation in a human being.
2. Description of the Prior Art.
For the purpose of studies and tests relating to the behaviour of the human body when subjected to certain external loads, particularly as the occupant of an automobile vehicle, use has been made of anthropomorphological dummies in which instruments have been placed for measuring various phenomena to which they are subjected. The principle disadvantage of previously proposed dummies resides in their lack of true representation of the human body, because of their construction, in particular with regard to the physiological compensation at the level of the trunk of the human body.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a hydro-pneumatic system for a anthropomorphological dummy comprising a thoracic-abdominal cavity confined by an envelope enclosing a rachis, and, in its upper part, a rib assembly connected to the rachis and defining with a sternum, a thoracic cage, said system comprising a first fluid-tight inflatable pocket disposed in the interior of the said thoracic cage, an alveolate air permeable material simulating the lungs and enclosed within the first pocket, a body fixed to the internal wall of said pocket, and simulating the heart, a second fluid-tight resilient pocket in the interior of the abdominal cavity of the dummy, said second pocket being arranged to be filled with a liquid, bodies enclosed within the second pocket and simulating respectively the liver, the spleen, and the pancreas, said bodies being fixed to the internal wall of the pocket, a hollow inflatable ring enclosed within the second pocket, said ring simulating the intestines, said ring being fixed at a single point to the said second pocket, and fluid connections leading from the first and second pockets and the ring to the exterior of the dummy whereby fluid can be fed through the connections to the first and second pockets and the ring, each said connection comprising valve means.
Further according to the present invention, there is provided in an anthropomorphological dummy, means defining a thoracic cage, a first, inflatable, pocket located within the cage, said pocket being composed of a resilient material, bodies enclosed within the first pocket to simulate internal organs of the body, means defining an abdominal cavity, a second pocket located within said cavity, said second pocket being composed of a resilient material, bodies enclosed within the second pocket to simulate further internal organs of the body, an inflatable tube located within the second pocket to simulate the intestine, first valve means operative to connect the first pocket to a source of gas, second valve means operative to connect to second pocket to a source of liquid, and third valve means operative to connect the tube to a source of gas.
Preferably, there is provided between the two pockets a resilient membrane of predetermined elasticity, simulating the diaphragm, and connected in a demountable manner by means of hooks at its external contour, to the lower part of the aforesaid rib assembly and to the lateral parts of the rachis. Alternatively, the membrane can be formed by an upper reinforced part of the second pocket.
The pockets and the membrane preferably define, with the lower part of the rachis, a free space.
Advantageously, the pockets and the membrane are of an elastic material having a predetermined elasticity and resistance and the elements forming the heart, the liver, the spleen, and the pancreas are of semi-hard material and the element forming the intestines is of flexible rubber.
Preferably, the valve means for the first pocket extends to the outside of the dummy above the sternum, the valve means for the second pocket extends to the outside of the dummy at the level of the navel and the valve means for the ring likewise extends to the outside of the dummy at the level of the navel.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the invention will now be described by way of example only, with reference to the accompanying diagrammatic drawings, in which:
FIG. 1 is a view in section from the front of a dummy provided with a system in accordance with the invention;
FIG. 2 is a view in section of the side of the dummy;
FIG. 3 is a section, to an enlarged scale, taken on line III--III of FIG. 1;
FIG. 4 is a section, to an enlarged scale, taken on line IV--IV of FIG. 1;
FIG. 5 is a section, to an enlarged scale, taken on line V--V of FIG. 2; and
FIGS. 6 and 7 are sections, to enlarged scales, taken on lines VI--VI, and VII--VII respectively, of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIGS. 1 and 2, an anthropomorphological dummy comprises a trunk 1 defining the thoracic-abdominal cavity, in which is placed a rachis 2. A thoracic cage comprising a rib assembly 3 is connected at the rear to the rachis 2 and at the front to a sternum 4. The rib assembly 3 contains a fluid-tight pocket or chamber 5 of an elastic material (for example rubber) having a predetermined resistance, the pocket 5 enclosing an alveolate material 6 simulating the lungs, and a compact body 7 of semi-hard material (for example semi-hard rubber) simulating the heart.
The pocket 5 has an air inlet valve 8 leading to the outside of the dummy above the sternum 4. The valve 8 is provided with a female screw thread and enables connection of the pocket 5 to a compressed air source in order to effect, and to maintain, inflation of the pocket 5 at a predetermined pressure. The alveolate material 6 is permeable to air to enable the filling of each of its alveoles to the aforesaid pressure. The body 7 is fixed at several points to the internal wall of the pocket 5.
The portion of the abdominal cavity situated below the thoracic cage contains a second fluid-tight pocket or chamber 9 of an elastic material (for example rubber) having a predetermined resistance, the pocket 9 enclosing bodies 10, 11 and 12 of semi-hard material (for example semi-hard rubber) secured partially to its internal wall and simulating, respectively the liver, the spleen, and the pancreas. The pocket 9 also contains a hollow ring 13 of flexible rubber simulating the intestines.
A valve 14 extending externally of the dummy at the level of the navel is connected to the pocket 9 and is arranged for connection to a source of liquid. In this manner a predetermined, controllable, quantity of liquid having a controllable and predetermined viscosity can be injected into the pocket 9. A valve 15 also extending externally of the dummy at the level of the navel is connected to the hollow ring 13, the valve 15 being arranged for connection to a source of compressed gas, for example air, in order to permit, and to maintain, inflation of the ring 13 at a predetermined pressure. The passage of the valve 15 through the pocket 9 constitutes the sole point of securing of the ring 13 to the pocket 9. The ring 13 thus constitutes a loop which can, in effect, float in the liquid contents of the pocket 9. A domed membrane 16, concave downwards, simulates the diaphragm and is disposed between the pocket 5 and the pocket 9. The membrane 16 is of flexible rubber of predetermined elasticity connected as described below, to the lower edges of the rib assembly 3 and to the lateral faces 2 a of the rachis 2. This membrane is capable of being interchanged as a function of the desired elasticity of the diaphragm.
As can be seen from FIG. 3, the dummy is equipped in a known manner at the level of the lower face of the rachis with a measuring device such as an accelerometer 17. The shape of the pocket 5 is such that it defines, with the rachis, a free space 18 in which other suitable measuring devices are located. At the level of the abdominal zone as shown in FIG. 4, it will be noted that the pocket 9 also defines a free space 18 with the lower face of the rachis 2 in such a manner to provide a passage for conductors 19 which lead from the measuring devices to associated apparatus (not shown) externally of the dummy. The conductors 19 extend externally from the dummy at the level of the lumbar region as schematically shown in FIG. 2.
FIG. 5 shows the disposition and the connection of the membrane 16 in relation to the other elements of the dummy. It will be seen that a series of hooks 20 is disposed at the periphery of the membrane 16 and the hooks engage the second row of ribs of the assembly 3. This fixing arrangement is illustrated in FIG. 6 in which a hook 20 is constituted by two parts 20a and 20b defining between them a space capable of containing one rib 3. The part 20a of the hook is rigid with the membrane 16 whilst the part 20b is fixed in position on the part 20a for example by means of a rivet or a pin indicated at 21. The attachment of the membrane 16 on the hook 20 is demountable.
The membrane 16 is secured to the sides 2a of the rachis 2, as shown in FIG. 7, by a securing strap 23 fixed by suitable means to the rachis and having a curved part 23a which is connected in known manner to the membrane 16. This arrangement, at the level of the rachis 2 enables the preservation, at the height of the diaphragm, of the space 18 for the passage of the conductors 19,
The dummy described above is suitably representative of the human body. In fact, the pocket 5 and the ring 13 being inflatable to the desired pressures, and the pocket 9 being filled with a predetermined quantity and viscosity of liquid, the assembly being joined to the elasticity of the pockets and to the skin of the dummy, provides a certain hydro-pneumatic balance of the thoracic-abdominal system in the trunk of the dummy. By varying the pressures of the gas contained in the lung-forming parts 6 the intestine-forming part 13 and on the quantity and viscosity of the fluid admitted into the pocket 9, it is possible to modify at will this state of balance and thus to simulate a large number of different states in which the human body may exist in real life. In practice the air pressure admitted into the lung-forming parts 6 will be slightly in excess of the pressure normally encountered in the human body in order to take into account the action of the intercostal and thoracic muscles.
The freedom of movement which the ring 13 has in the interior of the pocket 9 simulates fairly accurately the variable positions which can be taken up by the intestines of a human body when they are subjected to different variations in pressure. Further, possibility of replacing the diaphragm by a diaphragm of a different initial elasticity enables the dummy to be modified in order to take into account various human constitutions liable to be encountered.
The disposition and form of the elements as particularly described advantageously enable the measuring devices to be grouped along the vertebral column with a single exit being provided at the level of the lumbar region of the dummy for the associated conductors.
In a modified form (not shown) there may be no independent diaphragm, the pockets 5 and 9 being directly in contact with one another at the lower level of the thoracic cage of the dummy, the lower pocket being reinforced at this level.
The dummy particularly described is particularly suitable for use in studies and tests relating to the behaviour of the human body submitted to various conditions, particularly in an automobile subject to deceleration and shocks.
The system particularly described can be used with anthropomorphological dummies at present in existance to enable an improvement of their behavoural characteristics by simulating in a precise manner the hydro-pneumatic thoracic-abdominal compensation as a function of the conditions to which it is subjected. | An anthropomorphological dummy for studying the behavior of the human body, for example as the occupant of an automobile involved in an accident, comprises a thoracic cage housing an air inflatable pocket containing bodies simulating the lungs and the heart. A liquid-filled pocket located within an abdominal cavity contains bodies simulating the liver, the spleen, and the pancreas. An air-inflatable ring simulating the intestines is located within the liquid-filled pocket and is attached thereto at one point. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a method for generating offset surface data. More particularly, the invention relates to a method for generating offset surface data particularly applicable in designing and manufacturing of contoured products utilizing data representing a free surface generated through computer aided design (CAD) and/or computer aided manufacturing (CAM) for example.
2. Description of the Background Art
In the case where the contour of the object defined by the free surface is designed using CAD technique (so called, geometric modeling), the designer generally specifies a plurality of points (articulation points) in a three dimensional coordinate system through which the surface is to pass and uses a computer to calculate a boundary line network interconnecting the plurality of specific articulated points on the basis of desired vector functions. A surface represented by a "wire frame" is thus generated. In this way, a multiple number of frame spaces enclosed with boundary lines can be formed. Such a process is called frame processing.
The boundary line network formed through the above-mentioned frame processing represents a rough sketch to be designed by the designer. If a surface which can be represented by predetermined vector functions using boundary lines enclosing each frame space can be interpolated, the free surface desired by the designer (which is impossible to specify by means of a quadratic function) can, as a whole, be generated.
The surface extended over each framed space forms a basic element constituting the whole surface and is called a "patch".
To provide a more natural outer contour for the generated entire free surface, a free surface generating method has been proposed in which a control side vector around a common boundary is set again so as to extend a patch to satisfy the condition of continuity of the osculating planes at the common boundary bridging the two frame spaces.
U.S. Pat. No. 4,819,192 exemplifies the above-mentioned free surface generating method. The free surface generating method disclosed in the aforementioned United States Patent will be described with reference to FIGS. 10 and 11.
In the case where two patches S(u, v) 1 and patches S(u, v) 2 are smoothly connected to each other, e.g., as shown in FIG. 10, control side vectors a 1 , a 2 , c 1 and c 2 so as to establish a condition of continuity of the osculating plates are, in principle, set on a common boundary COM 12 bridging adjoining patches S(u, v) 1 and S(u, v) 2 on the (basis of articulated points P(00), P(30) 1 , P(33) 1 , P(03), P(33) 2 and P(30) 2 derived through the frame processing internal control points P(11) 1 , P(12) 1 , P(11) 2 and P(12) 2 which are set once again by means of these control side vectors.
If the above-described techniques is applied to other common boundaries, the two patches S(u, v) 1 and S(u, v) 2 can be smoothly connected to other adjoining patches under the condition of continuity of the osculating planes. It is noted that "osculating plane" means a plane formed by tangent vectors in the u and v directions at each point of the common boundary For example, when at each point on the common boundary COM 12 of FIG. 10, the osculating planes of the patches S(u,v) 1 and S(u, v) 2 are the same, the condition of continuity of the "osculating planes" is established.
In detail, the condition of continuity of the osculating planes at a point (o, v), wherein u=o and v=v, on the common boundary COM 12, is determined as shown in FIG. 10. That is to say, for the one patch S(u, v) 1 a normal vector n 1 for a tangent vector Ha in a direction traveling the common boundary COM 12 (i.e., u direction) and a tangent vector Hb in a direction along the common boundary COM 12 (i.e., v direction) can be expressed in the following equation:
n.sub.1 =Ha×Hb (1)
In addition, for the other patch S(u, v) 2 a normal vector n 2 for a tangent vector Hc in a direction traversing the common boundary COM 12 and a tangent vector Hb in a direction along the common boundary COM 12 can be expressed in the following equation:
n.sub.2 =Hb×Hc (2)
Since the two sets of tangent vectors Ha, Hb and Hc must be present on the same plane, respectively, to establish the condition of continuity of the osculating planes under such a condition as described above, the two normal vectors n 1 and n 2 are consequently directed in the same sense.
To achieve this condition for the two normal vectors n 1 and n 2 , the internal control points P(11) 1 , P(21) 1 , P(12) 1 , P(22) 1 and P(11) 2 , p(21) 2 , p(12) 2 , p(22) 2 may be set so as to establish the following equation: ##EQU1##
In the equation (3), λ(v), μ(v) and (v) denote scalars.
Furthermore, the patches S(u, v) 1 and S(u, v) 2 are represented using a vector function S(u,v) of a cubic Bezier equation:
S(u, v)=(1-u+uE).sup.3 ·(1-v+vF).sup.3 ·P.sub.(00) ( 4)
It is noted that u and v denote parameters in the u direction and in the v direction and E and F denote shift operators.
In the practical production, an article defined by a plurality of patches S(u, v), (S(u, v) 1 , S(u, v) 2 ...) is formed by utilizing a female or reversed configuration die. For this, such a female or reversed configuration die has to be prepared. Practically, such a female die is made from a rectangular parallel-piped configuration of a material block. The material block 1 (FIG. 12(A)) is drilled to remove extra material to form a plurality of straight bores 3 respectively having depths substantially corresponding to the depths of the die recess at the corresponding position according to the desired configuration of the curved surface 2, as shown in FIG. 12(A). Subsequently, the remaining materials 4 and 5 are removed by means of a ball end mill to form the recess 6 (FIG. 12(B)). Such a machining process may require approximately 70% of the process period for producing the female die. The process illustrated herein successfully reduces the process time for the aforementioned rough machining. Therefore, with the shown process, the efficiency in production of the female die can be significantly improved.
Here, as shown in FIG. 13, the radius R D and the curve radius R of a drill DR and ball end mill BM are diametrically selected to satisfy the following equation:
R.sub.D ≃0.8R (5)
The drill DR is provided with a working edge angle θ 1 (=2θ 2 ) at the working edge and the ball end mill has essentially a semisphere head. By means of the drill DR and the ball end mill BM, the machining processes are performed utilizing identical machining data which define the path of the tools.
The machining data for defining the path of the tool for machining a free or random surface is determined in the process disclosed in U.S. Pat. No. 4,789,931.
Namely, as shown in FIG. 14, among all of patches defining the free or random surface 2 of the female die, a randomly selected patch S(u, v) is separated into a predetermined number of segments. In the example of FIG. 14, the patch S(u, v) is separated or divided into sixteen segments by dividing it into four segments in the respective u and v directions. Then, the parameters are thus divided into the u and v directions. Tangent vectors n at the respective dividing points are obtained (e.g. see FIG. 11). Thereafter, the offset vector F at each dividing point is derived on the basis of the tangent vector n and the curve radius R of the ball end mill. The magnitude of the offset vector F can be expressed with the equation:
F=Rn (6)
Then, offset points P 1 ,P 2 , P 3 . . . are derived from the offset vector thus derived. By connecting three mutually adjacent offset points, a triangular plane P 1 -P 2 -P 3 is established. By this, an offset surface defined by a plurality of triangular planes can be defined.
For generating free or random surface machining data, three dimensional machining point matrix MTX is projected on a two-dimensional X-Y plane. The matrix MTX covers all surface configurations and is constituted by a plurality of machining points (at the intersection of the grid lines) separated by a pitch determined on the basis of the radius R D of the drill DR and the curve radius R of the ball end mill BM. In the X-Y coordinate system of the X-Y plane, respective ones of the machining points can be defined by the x- and y-coordinates (x ij , y ij ).
Subsequently, with respect to the triangular plane projected on the matrix MTX and defined by the coordinates (x 1 , y 1 ), (x 2 , y 2 ) and (x 3 , y 3 ), regions defined by (x min , x max ) and (y min y max ), in which machining points (x ij u ij ) to determine the machining data are present, as shown in FIG. 15. Then, with respect to each machining point, a determination is made of whether it is within the projection of the triangular plane on the matrix MTX. For the machining points oriented within the projection of the triangular plane as identified by solid dots in FIG. 15, the height z ij is derived by the foregoing equation (6). The height z ij thus derived represents the offset magnitude at the corresponding machining point. By repeating the foregoing process for all of the machining points and for all of the triangular planes, machining data is derived including orientation (x ij , y ij ) of the machining point with height data z ij . Therefore, each grid point on the matrix MTX can be defined. Such machining data is suitable for rough machining by means of a drill and ball end mill.
The foregoing process is successful for deriving machining data as long as the adjacent offset planes form a continuous surface. However, in the case that the surface to be machined has a discontinuity such as that shown in FIG. 16, difficulty is encountered in generating the machining data. For instance, in the example of FIG. 16, if the random surface to be machined is constituted of the patches S 1 , S 2 , S 3 , S 4 , S 5 . . , the offset planes S off1 , S off2 , S off3 , S off4 , S off5 . . , become discontinuous. As can be seen, in the shown example, the offset planes S off2 , S off3 and S off3 , S off4 of the surfaces S 2 , S 3 and S 3 , S 4 form a discontinuous surface to make it impossible to form grid points.
For solving this problem, U.S. Pat. No. 4,866,631, which has been assigned to the common assignee to the present invention, proposes a process which enables the generation of an offset surface when a discontinuity of the offset surfaces is established with respect to the surface to be machined.
Although the process proposed in the aforementioned U.S. Pat. No. 4,866,631 is successful in generating the offset surface despite the presence of discontinuity, a large amount of arithmetic data processing is required. Therefore, when the surface to be machined consists of complex configurations and thus has a large number of patches, the process time becomes substantial. Furthermore, in the proposed process, the triangular planes forming the offset planes are formed by dividing parameters into a predetermined number which is fixed irrespective of the size of the patch. Therefore, as shown in FIG. 17, greater error between the offset surface T and the approximated triangular plane π T (P 1 -P 2 -P 3 ) can be induced for a greater patch. As a result, the grid points GP formed on the triangular plane π T tend to be oriented at lower elevations than the point Px on the surface to be machined in a magnitude ΔZ. Therefore, the problem of excessive machining can arise.
Furthermore, determining whether the grid points are oriented within or out of the triangular project prolongs the process time.
SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention is to provide a method for generating free surface machining data while solving the problems set forth above.
Another object of the present invention to provide a method for generating rough depth machining data based on the free surface data without using an offset surface.
A further aspect of the invention to provide a method for generating rough depth machining data while successfully avoiding excess machining.
In order to accomplish the aforementioned and another objects, a method for generating data defining the machining depth of a tool path for a numerically controlled machine, according to the present invention, generates machining tool path depth data without establishing offset plane data so that the machining tool path depth data can be established for discontinuous, surfaced, offset planes which might otherwise cause interference in the tool path. The method includes the steps of forming a plurality of patches defining a three-dimensional plane to be machined and dividing each patch into a predetermined number of segments as divided by a plurality of dividing points. The number of segments is variable depending upon the distance between adjacent dividing points so that the distance is maintained to be smaller than the machining area of a machine tool. The machining depth at respective ones of a plurality of the dividing points is then derived with respect to the maximum height position at which the machining tool comes into contact with the dividing point. The machining depth is then modified with a correction value which is determined in terms of the surface condition of the surface to be machined.
According to one aspect of the invention, a method for establishing data defining the machining depth of a tool path for a numerically controlled machine of the type having a machining tool of a known configuration from data defining a three-dimensionally curved surface comprises the steps of:
(a) dividing the three-dimensionally curved surface into a plurality of patches;
(b) subdividing each of the patches for establishing a plurality of dividing points;
(c) comparing the distance between adjacent dividing points with given value which is derived in relation to the size of the machining tool;
(d) re-subdividing some of the patches until all of the distances between each of the adjacent dividing points become smaller than a given value, where the distance as compared at the step (c) is greater than the given value;
(e) projecting the patches formed in step (d) onto a three dimensional machining matrix projected onto an X-Y plane, projecting the machining tool onto the machining matrix in the X-Y plane and selecting those patches whose projections on the machining matrix are located within the projection of the machining tool;
(f) selecting a plurality of grid points on the machining matrix which lie within the projection of the patches determined in step (e) and which are inside of the projection of the machining tool onto the X-Y plane;
(g) calculating the maximum height of the center of the machining tool when the machining tool contacts with each of the dividing points; and
(h) adding a predetermined correction value to the maximum height for determining the height position of the machining tool in the tool path.
Preferably, the predetermined correction value (Z AD ) is derived from one of the following equations: ##EQU2## where R is radius of the machining tool;
R ref is a reference value (R ref ≦R; and
δ is a Value corresponding to a finishing margin.
Also, the dividing points satisfying the following formula may be selected as dividing points oriented within the section area of the machining tool:
(x.sub.i -x.sub.a).sup.2 +(y.sub.i -y.sub.a).sup.2 ≦R.sup.2
where
x i , y i are x- and y-coordinate components of a grid point within the section area;
x a , y a are x- and y-coordinate components of the grid point at which the center of the machining tool is located; and
R is the radius of the machining tool.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood more fully from the detailed description given herebelow and from the accompanying drawings of the preferred embodiment of the invention, which, however, should not be take to limit the invention to the specific embodiment but are for explanation and understanding only.
In the drawings:
FIG. 1 is a block diagram of CAD/CAM system employing the preferred embodiment of a machining data generating method according to the present invention;
FIG. 2 is a flowchart showing the preferred process of the machining data generation to be performed for implementing the preferred, machining data generation method of the invention; FIGS. 3,4,5,6,7A,7B,7C,8A,8B,9A,9B,9C, and 9D are illustrations used for explaining the respective processes at respective steps in the process of FIG. 2;
FIG. 10 is a explanatory illustration showing the connection between adjacent patches in a prior art method;
FIG. 11 is an explanatory illustration for explaining continuity of surfaces in a prior art method;
FIGS. 12A, 12B, 13, 14, and 15 are explanatory illustrations showing the manner of generation of machining data in the prior art;
FIG. 16 is an explanatory illustration showing an example of a surface configuration having discontinuous surfaces in the prior art; and
FIG. 17 is an explanatory illustration of how error in the generation of the machining data can occur in the prior art method.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, particularly to FIG. 1, the preferred embodiment of a machining data generating method, according to the present invention, is applicable for a CAD/CAM system as illustrated. The CAD/CAM system is generally represented by the reference numeral "10". The CAD/CAM system 10 includes a free or random surface generating system 12, a tool path data generating system 13 and a numerically controlled (NC) milling machine (machining center) 14. Respective of the free or random surface generating system 12, the machining data generating system 13 and the NC milling machine (machining center) 14 are each provided with their own CPUs.
The free surface generating system 12 generates the outer surface data DT s of a desired configuration of the article, which outer surface is defined by a plurality of interconnected quadrilateral patches S(u, v). For generating the outer surface data DT s , CAD technology may be used. The tool path data generating system 13 receives the outer surface data DT s from the free surface data generating system 12. Based on the received outer surface data DT s , the tool path data generating system 13 generates machining data for rough machining by means of a drill DR and a ball end mill BM. Then, the machining data generating system 13 generates tool path data DT cL on the basis of the machining data.
The tool path data DT CL is supplied through an appropriate medium, such as a floppy disk, on-line network and so forth, to the machining center 14. In the machining center, the drill DR and the ball end mill BM are driven through the tool path defined by the tool path data DT CL to perform rough machining. Through the process set forth above, a female die 1 (see FIGS. 12(A) and 12(B)) for production of the desired outer surface configuration can be rough machined.
It should be appreciated that the tool path data generating system 13 is associated with a display unit 16 and an input unit 17 which comprises a keyboard, mouse and so forth, for example. The designer or engineer can enter operation data through the input unit 17 while visually observing a menu or displaced graphic image and so forth on the display unit 16. Based on the entered operation data and the machining data derived on the basis of the outer surface data DT s from the outer surface data generating system 12, the tool path data is derived.
The CPU in the tool path data generating system 13 is responsive to a command entered through the input unit 17 for generating the tool outer surface data DT s . The process of deriving the tool path data DT CL is illustrated in FIG. 2. This process begins execution at a step RTO. Subsequently, at a step SP 1 , free surface data DT s defined by a plurality of patches S(u, v) and representing the free surface to be machined is read out from the free surface data generating system 12. Subsequently, at the step SP 1 , parameters defining each patch S.sub.(u, v) in the free surface data DT s are divided into a predetermined number BN in order to establish a plurality of segments in each patch. Through this process, each patch is defined by a plurality of point data, as shown in FIG. 3. In the shown example in FIG. 3, the parameters defining each patch are divided by four in u and v directions to produce sixteen segments. Therefore, in the shown example, the patch is defined by twenty-five dividing points P(.sub.(00)s ˜P.sub.(04)s, P.sub.(10)s ˜P.sub.(14)s, P.sub.(20)s ˜P.sub.(24)s, P.sub.(30)s ˜P.sub.(34)s and P.sub.(40)s ˜P.sub.(44)s. These dividing points as generally referred to will be hreinafter represented by P.sub.(i j)s, i, j=0, 1, 2, 3, 4.
At a step SP 2 , the distance between adjacent dividing points is derived. In the process of step SP 2 , for dividing point P.sub.(i j)s, the distance in the x-coordinate component (distance in a projection on the X-Z plane of the coordinate system), the y-coordinate component (distances in projections on the X-Y plane and the Y-Z planes of the coordinate system) and the z-coordinate component (distances, in projections on the X-Z and the Y-Z planes) to dividing points P.sub.(i+1 j)s, P.sub.(i j+1)s, P i+1 j+1)s are derived. Subsequently, from the result of the foregoing process of derivation of the distances between the adjacent dividing points maximum values X dis , Y dis and Z dis are derived. These maximum values X dis , Y dis and Z dis are compared with a predetermined criterion R ref . This can be expressed by:
X.sub.dis >R.sub.ref (7)
Y.sub.dis >R.sub.ref (8)
Z.sub.dis >R.sub.ref (9)
Therefore, a check is performed whether one of the formulae (7), (8) and (9) is satisfied. The predetermined criterion R ref is determined in relation to the radius R of the ball end mill BM so that the value of the predetermined criterion is smaller than or equal to the radius of the ball end mill. When one of the foregoing formulae (7), (8) and (9) is satisfied, an arithmetic process is executed to determine a new dividing number BN new so that the maximum values X dis , Y dis and Z dis become smaller than the predetermined criterion R ref . In practice, the new dividing number is derived through the following equation:
BN.sub.new =(INT[D.sub.xys /R.sub.ref [+1)×BN (10)
where
D xys is respective of the maximum values X dis , Y dis and Z dis of the x-, y- and z-coordinate components; and
INT[] is an operator for deriving the integer of the value in the parenthesis.
The foregoing process is performed for the patches having the maximum distances, one of which satisfies the foregoing formulae (7), (8) and (9). Through the foregoing process, the patches having greater maximum distances X dis , Y dis and Z dis than the predetermined criterion R ref can be separated into smaller segments.
Furthermore, the maximum and minimum values X max , Y max , Z max and X min , Y min , Z min of x-, y- and z-coordinate components are derived. Subsequently, in a manner similar to that illustrated with respect to FIG. 15, the x- and y-coordinates of the respective grid points GP with pitches corresponding to the radius R of the drill DR and the curve radius RD of the ball end mill BM are set with respect to the overall area of the projection of the free surface projected on the X-Y plane, at a step SP 3 . As previously explained in reference to the grid points set in the prior art process, the respective grid points are identified by x- and y-coordinates on the x-y coordinate system established on the X-Y plane and the combination of the grid points defines the free surface projection on the X-Y plane.
At a step SP 4 , as shown in FIG. 4, with respect to each of the grid points, a projection of the ball end mill BM on the X-Y plane centering at each grid ,point GP is established. Then, patches S u ,v) whose projections are oriented within an with an area BM xy of the projection of the ball end mill are extracted. In order to make a judgment whether the patches are oriented within or outside of the projection area BM xy , a square region having an edge length corresponding to the diameter (2R) of the ball end mill, which is defined by the x- and y-coordinates of D xmin , D xmax , D ymin , and D ymax , is established. Then, these coordinate data D xmin , D xmax , D ymin and D ymax of the square are compared with the maximum and minimum coordinate values X max , X min , Y max , Y min Z max , and Z min to check whether the following formulae are satisfied:
X.sub.max ≧D.sub.xmin (11)
X.sub.min ≦D.sub.xmax (12)
Y.sub.max ≧D.sub.ymin (13)
Y.sub.min ≦D.sub.ymax (14)
Z.sub.max +R>GZ.sub.max (15)
wherein GZ max represents the z-coordinate value of the grid point GP, which is set at a minimum value Z min of overall z-coordinate components on the free surface.
when all conditions set in the foregoing formulae (11), (12), (13), (14) and (15) are satisfied, a judgment can be made as to whether an X-Y projection of a given patch S.sub.(u,v) is oriented within the projection area BM xy . At the process of the step SP 4 , all patches whose X-Y projections are oriented within the projection area BM xy can be extracted. In the example of FIG. 4, four patches S.sub.(u,v)1 to S.sub.(u,v)4 are extracted with respect to the grid point GP a which the ball end mill BM is centered. The X-Y projection of each patch S.sub.(u,v)1 to S.sub.(u,v)4 encompasses 25 (i.e. 5X5) grid points, which appear as solid or hollow dots in FIG. 5. When another patch is oriented beneath the extracted patch, such patch may not be extracted because of a smaller maximum z-coordinate component Z max than that of the extracted patches. By this way, unnecessary interference with the tool path can be successfully avoided.
At a step SP5, a further judgment is made as to whether the grid points GP.sub.(ij)s1, GP.sub.(ij)s2, GP.sub.(ij)s3, GP.sub.(ij)s4 on the X-Y projections of the extracted patches S.sub.(u,v)1 to S.sub.(u,u)4, respectively, are within a circular projection BM xy (centered at the grid point GP) of the ball end mill BM on the X-Y plane. In practice, a judgment whether the grid points GP.sub.(ij)s1, GP.sub.(ij)s2, GP.sub.(ij)s3, GP.sub.(ij)s4 are out of or within the circular projection area is performed through the following process. For the respective grid points GP.sub.(ij)s1, GP.sub.(ij)s2, GP.sub.(ij)s3, GP.sub.(ij)s4, the x- and y- coordinate component data are derived as x i and y i . Subsequently, the x- and y- coordinate component data of the associated grid point GP of the center of the ball end mill BM are set as x a and y a . Then, a circular area is calculated and compared with the radius R of the ball end mill BM through the following formula:
(x.sub.i -x.sub.a).sup.2 +(y.sub.i -y.sub.a).sup.2 ≦R.sup.2 (16)
By substituting the data of the grid points GP.sub.(ij)s1, GP.sub.(ij)s2, GP.sub.(ij)s3, GP.sub.(ij)s4, grid points satisfying the foregoing formula are selected as those oriented within the circular projection. In the shown example of FIG. 5, the grid points identified by hollow circles (o) are the grid points judged as being oriented within the circular projection.
Keeping in mind that the machining matrix is three dimensional, so that there are grid points which are coincident with the patches, with respect to those of the grid points GP ijs1 , GP.sub.(ij)s2, GP.sub.(ij)s3, GP.sub.(ij)s4 for which a judgment is made that they are oriented with the circular projection area, a z-coordinate position at which the center of the ball end mill BM comes into contact with each grid point on the patch is derived. Among a plurality of z-coordinate position data of the contact grid points, the highest point is selected.
The z-coordinate of the center of the ball end mill is derived in the manner illustrated in FIG. 6. As shown in FIG. 6, from among each of the grid points GP.sub.(ij)s1, GP.sub.(ij)s2, GP.sub.(ij)s3, GP.sub.(ij)s4 on the patches S.sub.(u,v)1 to S.sub.(u, v)4, each grid point oriented within the circular projection BM is set as GP IN in the three-dimensional machining matrix. For the each point GP IN , x-, y- and z-coordinate position data are derived as x i , y i and z i . The x-, y- and z-coordinate position data of a grid point GP at the center of the ball end mill BM is then set as x a , y a and z a . Then, the equation of a sphere is established:
(x.sub.i -x.sub.a).sup.2 +(y.sub.i -y.sub.a).sup.2 +(z.sub.i -z.sub.a).sup.2 =R.sup.2 (17)
From the foregoing equation (17), the z-coordinate component z a can be derived by: ##EQU3## The z-coordinate position data z a thus derived is compared with the z- coordinate position data GZ max of the grid point GP to set a new grid point z-coordinate data GZ max which is the greater one of the two. Through this process, the grid point z-coordinate data GZ max can be set at the maximum value of the z-coordinate data z a of the points.
As can be appreciated, the process at the steps SP 4 and SP 5 are repeated for deriving z-coordinate data GZ max for all grid points GP.
Subsequently, at a step SP6, in order to prevent excess milling or curving, correction for the z-coordinate data GZ max is performed with a predetermined correction value Z AD . The corrected z-coordinate data is set as the grid point z-coordinate position data GZ max . Subsequently, at a step SP7, the process of generating the free surface data is finished.
It should be noted that the correction value Z AD is determined with respect to the condition of the points P IN on the patches S u , v)1 to S.sub.(u, v)4, about Which the z-coordinate position data GZ max are derived through the foregoing process. Namely, as shown in FIG. 7(A), if the z-coordinate position data GZ max is derived with respect to one point P IN on one plane patch S(u, v) defining the plane surface, the correction value can be derived from the following equation:
Z.sub.AD =0+δ (19)
where, again, δ is the value corresponding to the finishing margin. At this time, since the patch S(u, v) is a plane, the maximum value Z max and minimum value Z min of the z-coordinate position are equal to each other. Therefore, the z-coordinate data GZ max at the grid point GP can be expressed by:
GZ.sub.max =Z.sub.max +R+δ (20)
On the other hand, when the z-coordinate data GZ max of the grid point GP is derived with respect to one point P In on the patch S(u, v) defining curved surface, the correction value Z AD may be derived by taking the surface configuration as illustrated in FIG. 7(B) into account and is expressed by: ##EQU4## or by taking the surface configuration as illustrated in FIG. 7(C) into account to be expressed by:
Z.sub.AD2 =R.sub.ref +δ (22)
Whichever is the greater of the values of Z AD1 and Z AD2 taken as the correction value Z AD .
When the z-coordinate data GZ max of the grid point GP is common to more than one patch, e.g. S(u, v) 1 and S(u, v) 2 , and when the point P IN , based on which the z-coordinate data GZ max is derived, is oriented on one of the patches S(u, v) 1 , the correction data Z AD1 derived through the equation (21) is used as the correction value Z AD .
In addition, as shown in FIG. 9(A), when the z-coordinate data GZ max of the grid point GP corresponds to a minimum value Z min of one of the patches S(u, v) 1 and to a maximum value Z max of the other patch S(u, v) 2 , the largest of the correction values Z AD1 and Z AD2 derived through the equations (21) and (22) is selected as the correction value Z AD10 for the patch S(u, v) 1 and the correction value Z AD1 derived through the equation (2i) is used as the correction value Z AD20 for the other patch S(u, v) 2 . Then, the greater of the correction values Z AD10 and Z AD20 is selected as the correction value Z AD . Furthermore, various configurations of surfaces as shown in FIGS. 9(B) to 9(D) for example, can be treated by deriving respective correction values Z AD11 and Z AD21 through the equations (21) and (22) and the largest one is selected for use as the correction value. Furthermore, in case that both patches are flat planes, the correction value Z AD can be derived through the equation (19) as set forth above.
As can be appreciated herefrom, the surface data generating process, according to the present invention, does not require the establishment of an offset surface. Therefore, the surface condition which may cause discontinuity on an offset surface does not affect the generation of the machining data. Furthermore, according to the invention, since the segments formed by dividing the respective patches are formed so that the size thereof is smaller than a given value determined according to the size of the mill to be used, one or more patches oriented on the projection of the mill is selected, and the maximum value of the z-coordinate value at the contact point where the mill contacts is established, it becomes possible to generate free surface machining data for rough machining without generating the offset surface.
While the present invention has been discussed hereabove in terms of the preferred embodiment of the invention, the invention should be appreciated to be restricted for the shown embodiment. The invention can be embodied in various fashion. Therefore, the invention should be interpreted to include all possible embodiments and modifications which can be embodied without departing from the principle of the invention set out in the appended claims.
Although the shown embodiment divides the parameters of the respective patches and compares the distance between the adjacent dividing points with a reference value corresponding to the radius of the ball end mill, the reference value may be set at any value as long as it is smaller than the radius of the ball end mill. By setting the reference value at a smaller value than the radius of the ball end mill, the accuracy in the z-coordinate values can be enhanced to prevent the occurrence of any machining error.
Furthermore, although the shown embodiment is exemplified by the process for generating the machining data of a frame space defined by a plurality of quadrilateral patches each of which is expressed by tertiary Bezier formula, it may be possible to employ patches defined by biquadratic or higher degree Bezier formulae. Furthermore, the configuration of the patch is not necessarily limited to the quadrilateral but can be triangular or any appropriate configuration. Furthermore, the patch may also be expressed by B-spline formula or Furgason's formula. | A method for generating data defining a tool path for a numerically controlled machine is designed for generating machining tool path data without establishing offset plane data so that the machining tool path depth data can be established for discontinuous, surfaced, offset planes which might otherwise cause interference in the tool path. The method includes the steps of forming a plurality of patches defining a three-dimensional plane to be machined, subdividing each patch into a predetermined number of segments as divided by a plurality of dividing points, with the number of segments being variable depending upon the distance between adjacent dividing points so that the distance is maintained to be smaller than the machining area of a machine tool. The machining depth at each dividing point within the tool path is derived with respect to the maximum height position at which the machining tool comes into contact with the dividing point. The machining depth is modified with a correction value which is determined in terms of the surface condition of the surface to be machined. | 6 |
OBJECTS OF THE INVENTION
It is an object of the present invention to provide new and improved measurement of the water content of a moving airstream, especially when the water is not in the vapor state.
SUMMARY OF THE INVENTION
In one form of the invention, an incoming airstream is channeled into a diffuser to reduce its speed. Heating coils heat the air in order to vaporize any water present. Then, a collection pipe draws off a portion of vaporized mixture and transmits it to a dew point meter at which the water content is ascertained. The remaining mixture bypasses the collection pipe and is expelled.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts one form of the invention.
FIG. 2 is an end-on view of the coil 27 in FIG. 1.
FIGS. 3 and 4 are graphs of expected performance of the invention which are used to establish isokinetic operation.
FIGS. 5 and 6 depict one configuration of the coil 27 in FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
An inlet 3 (or inlet channel) for receiving a sample of an incoming airstream 6 is a cylindrical opening defined by the tip of a nose cone 9, which tapers down to thin edges 12. This tapering causes only a small disruption to the incoming airstream 6, thus allowing the airstream within the inlet 3 to maintain the pressure, temperature, and velocity characteristics of the incoming airstream 6.
The nose cone 9 is heated by heaters 15 (not shown in detail) to prevent ice formation, especially at the tip 18, which would disrupt or block incoming airstream 6. One such heater is Model No. SC121, 15 Watts, available from Hot Watt, Inc., located in Danvers, MA.
The inlet expands in diameter from point or station 21 to station 24, thus acting as a diffuser, which reduces the air velocity and very slightly increases the static pressure. However, incoming water droplets or ice particles (both will be referred to as "particulates") will have a higher inertia than the air itself, and will probably not slow as much. Speed reduction of particulates present in the airstream 6 is obtained by physical contact with a preheater 27 in an enlarged preheating channel 28. The preheater 27 contains a Cal-Rod coil which is wound in the shape of a conical helix, the apex being at point 30. Cal-Rod is a trademark of ARI Industries, located in Addison, IL. Cal-Rod herein refers to a resistance heating rod composed of Nichrome wires separated by MgO insulation and housed in a stainless steel sheath and, in this case, having a diameter of 0.040 in.
The configuration of the preheating coil 27 is such that no particulates in the incoming airstream see a clear path to the apex 30. FIG. 2 shows a view, in grossly exaggerated form, of apex 30 seen by the incoming airstream 6. The preheating coil 27 obstructs most direct paths between the inlet 3 and the apex 30. Consequently, entering particulates strike the preheating coil 27, or are diverted as shown by arrows 33 in FIG. 1 by the turbulence on the air which is caused by the coil. The preheating coil 27, together with the enlarged diameter in the preheating channel 28, serve to slow down both the incoming airstream and particulates.
The helical shape of the preheating coil 27 serves to induce a swirl into the mixture which enhances mixing of the water/gas mixture, which promotes homogeneity, thus making the dew point measurement more accurate. The Inventors point out that the spaces between the coil allow gas to flow through them, and present no significant blockage to gas flow.
A primary heating coil 36 in the schematic square wave configuration shown, further heats the now-slowed airstream as the airstream travels downstream to a collection tube 39. Under a diameter of inlet 3 of 3/16 inch, with an incoming airstream speed of 100 feet per second, with a maximum particulate concentration of 40 gm water per m 3 air, with a heat dissipation of 30 watts in the preheating coil and 1600 watts in the primary heating coil, all water or ice is vaporized by the time it reaches point 41, which is at the mouth of the collection tube 39. Downstream of the collection tube 39, the channel tapers in nozzle 43 which exhausts in channel 45.
The collection tube 39 ducts the vapor/air mixture to a dew point meter (or hygrometer) 40 which indicates the water content of the air at the collection tube inlet, at point 41.
In order for the reading from the dew point meter to be meaningful, the airstream ingested by the inlet 3 at point 21, must be of the same composition as that at point 44 in the incoming airstream 6. This condition is satisfied if the incoming airstream 6 is maintained in a state called isokinetic in the inlet 3. Isokinetic means that all molecules, whether they be air, or water in the form of vapor, droplets, or ice, maintain their same velocity (i.e., the same kinetic energy) in traveling from point 44 to point 21. An extreme example of the absence of the isokinetic state would be illustrated by partially plugging the downstream channel 45. With such plugging, the incoming airstream 6 will be drastically slowed or stopped, but water particles entering the intake will not be slowed so greatly: some water particles will continue to enter.
In order to assure that the flow is isokinetic at the inlet 3, one adjusts the flow through the collection tube 39. This adjustment can be done by altering the speed of a pump 47 (which draws gases through the collection tube 39 and supplies it to the hygrometer 40) adjusting a valve 49, or by other means. Irrespective of the particular adjustment means used, details of adjustment will be explained with reference to FIGS. 3 and 4.
FIG. 3 is a generalized plot of sampling accuracy versus orifice velocity which is widely assumed to be correct in the particulate sampling art. Orifice velocity refers to the airstream velocity at the intake 3 in FIG. 1. Sampling accuracy refers to the correspondence of the particulate concentration at point 44 in FIG. 1 to the concentration at point 21. For example, if there are ten particles per cubic centimeter at point 44, but only nine at point 21, the accuracy is 90 percent.
The inventors point out that, for a given range 52 of inlet velocities, the sampling accuracy is, to a large extent, independent of velocity. For example, if the velocity changes from about 95 to 100 in FIG. 3, in moving from point 53 to point 56, the sampling accuracy only changes from about 98 to 100. This feature can be used to modulate the airflow in the collection pipe 39 by application of FIG. 4.
FIG. 4 is a plot of dew point temperature as a function of the flow rate through the collection tube 39 (and thus through a part of the intake 3 at steady-state) in FIG. 1. Region 58 corresponds to region 52 in FIG. 3, as will now be explained.
If operation is in region 52 in FIG. 3, then sampling accuracy is high. If the water content of the incoming airstream 6 is not changing, as is the case in steady-state, then changes in the dew point of the airstream in the collection tube 39 will result from deviations in water content within the collection tube 39 from that in the incoming airstream 6. Changes in sampling accuracy cause this deviation. But, since the changes in sampling accuracy are small in region 52, then the changes in measured dew point will be small.
Therefore, one adjusts the flow within the collection tube 39 until one finds the region 58 in FIG. 4 where the dew point change is least for a given flow change. One finds the region of least slope on the dew point/hygrometer tube flow plot.
Another way to view the adjustment which uses FIG. 4 is the following. In the regions to the left of point 61, flow rate in the collection tube 39 is low. The low flow rate can be viewed as being caused by a flow restriction in the downstream channel 45 in FIG. 1. Flow of gases into the inlet 3 is thus reduced, but the momentum of particulates will cause them nevertheless to enter the inlet 3 and be vaporized by heating coils 27 and 36. The mixture collected by the collection tube 39 becomes "rich," as it were, because water content is artificially high as compared with that in the incoming airstream 6. The dew point of a rich mixture is high as shown in FIG. 4.
On the other hand, when flow rate is high in the collection tube 39, in the region to the right of point 64 in FIG. 4, the action of the pump 47 can be viewed as causing an increase in air speed within the inlet 3. This causes the gases in the incoming airstream 6 to accelerate faster than the particulates in the inlet, with the result that particulate concentration in the inlet 3 goes down, and the mixture collected by the collection tube 39 becomes "lean." A lean mixture has a lower dew point, as shown in FIG. 4.
However, when the hygrometer flow rate is within range 58, the small change 67 of the dew point in jumping from point 61 to 64 indicates that the particulate content within the inlet 3 in FIG. 1 is approximately the same as that at point 44. The small change 67 in dew point with flow rate indicates that the orifice velocity is within the range 52 in FIG. 3, because that is the region where sampling accuracy changes little with changes in flow rate.
The preceding discussion has considered flow properties of the invention. This discussion will now turn to structural features. Cylindrical insulating sleeves 70 and 72 are constructed of Macor. Macor is a trademark of the Corning Glass Works, located in Corning, N.Y., and is used herein to refer generally to a machinable ceramic. Macor is a good electrical insulator at high temperature, but a poor thermal insulator. An air space 75 lies between the insulating sleeves 70 and 72 and an outer cylinder 77 which is preferably a stainless steel. Machined rings 80 support the insulating cylinders 70 and 72 and maintain the air space 75. The insulating air space 75 reduces heat loss from the coils 27 and 36 to the exterior. This reduction is important because the invention is intended to be used in freezing conditions, under a spray of freezing water and ice.
As stated above, downstream of the collection tube 39 is a nozzle 43 followed by a diffuser 45. These function as follows.
The inlet 3 and the diffuser 45 have external surfaces 3A and 45A which are tapered, thereby providing reduced disruption to the external airflow.
Representative diameters of the channel diameter at the stations identified in FIG. 1 are given in Table 1.
TABLE 1______________________________________Station Diameter______________________________________21 3/16 inch24 1/480 9/32 80A 3/884 3/887 5/1689 1/492 1/4______________________________________
The preceding discussion has described primary heating coil 36 as having a square wave shape for ease of explanation. However, in one form of the invention, the shape is that shown in FIG. 5. The circles 99 in FIG. 5 represent the cylindrical channel within the insulating sleeve 72. The heating coil 36 is divided into an upstream region 100 and a downstream region 102. In the upstream region 100, the heater wires lie on chords 36A-C of circles 99, the circles 99 being cross sections of the cylinder where the wires lie. Accordingly, the upstream wires 36A-C, when viewed together, appear as a triangle when seen from arrow 6 in FIG. 1, as shown in FIG. 6.
In the downstream region 102, the heater wires 36D-F lie on diameters of circles 99. The downstream wires again, when viewed together, appear as a starburst in FIG. 6 when viewed from arrow 6 in FIG. 1. This triangular-starburst wire configuration produces at least three results.
One, the upstream wires 36A-C tend to heat the walls of the insulating sleeve 72 in FIG. 5, while the downstream wires 36D-F tend to heat the air in the center 105 in FIG. 6 of the channel. Two, spacing out the wires 36A-F in circles 99 reduces drag as compared with an alternative, namely, placing all wires arranged to support the swirl introduced by the helical preheating coil 27. That is, if the swirl is clockwise when seen from arrow 6 in FIG. 1, then the upstream wires are also clockwise: when seen from arrow 6 in FIG. 1, a downstream wire 36B is positioned clockwise with respect to an upstream wire 36A.
In more complex terms, the swirling flow can be ascribed axial component 107 and circumferential component 109 in FIG. 5. As to the wires, when one travels axially, in the direction of component 107, from an upstream wire 36A to a downstream wire 36B, one must also have a circumferential component 109 in order to reach the downstream wire 36B.
An invention has been described for isokinetic collection and evaporation of particulate water in an airstream moving at, say, 100 feet per second. An inlet channel expands into a larger cross section, thereby reducing the air speed, thus reducing internal drag. The drag reduction is important because drag acts as a partial blockage of the inlet 3, thus rendering the inlet flow nonisokinetic with respect to the incoming airstream, as explained above. The speed reduction also increases the dwell time of the water/gas mixture within the probe, thus giving the heaters 27 and 36 more time to heat the gas. With a probe length (i.e., the distance between stations 21 and 92) of 22 inches, and with an air speed of 100 ft/sec, it takes about 0.183 seconds for the air mixture to travel externally from station 21 to station 92. The internal air takes about 0.524 seconds. A preheating coil 27 acts as an obstruction, causing incoming particulates to strike the coil, perhaps break up, and reduce in speed. A primary heating coil 36, of smaller diameter wire than the preheating coil 27 because it need not withstand the buffeting of incoming particulates, vaporizes the water particulates. The vaporized mixture, which has increased in speed somewhat because of the expansion due to the vaporization, is collected by a collection pipe 39 and transmitted to a hygrometer 40. The invention adjusts the flow in the collection pipe 39 in order to maintain the inlet in the isokinetic state.
Numerous substitutions and modifications can be undertaken without departing from the true spirit and scope of the present invention. | An incoming airstream is channeled into a diffuser to reduce its spread. Heating coils heat the air in order to vaporize any water present. Then, a collection pipe draws off a portion of vaporized mixture and transmits it to a dew point meter at which the water content is ascertained. The remaining mixture bypasses the collection pipe and is expelled. | 6 |
FIELD OF THE INVENTION
The present invention concerns nuclear magnetic resonance (NMR) pulse sequences such as those used in evaluating earth formations. More specifically, the invention relates to pulse sequences and data acquisition methods which eliminate the effects of spurious signals caused by mechanical resonances within the measurement apparatus.
BACKGROUND OF THE INVENTION
Pulsed nuclear magnetic resonance (NMR) measurements alternate between transmitting high-powered radio-frequency (r.f.) pulses and receiving low-level response signals in a matter of a few ten or hundred microseconds. The combination of a strong static magnetic field and radio frequency pulses tend to excite mechanical resonances within the measurement apparatus, which resonances in turn cause an interference signal induced in the receiver system by a microphonic effect.
It has long been known that the interference arising from imperfect “refocusing” pulses can be canceled by repeating the measurement with the r.f. phase of the refocusing pulses inverted. This phase reversal does not affect the NMR signal, but inverts the phase of the interference. By acquiring both magnitude and phase of the compromised signals and by adding complex-valued measurements, the NMR signal is enhanced, while the “refocusing” interference is eliminated.
The above error cancellation scheme has become standard in practice, but it does not address interference problems arising from the “excitation” pulse, which typically is the first pulse in a long series of pulses. Changing the excitation phase would also change the phase of the NMR signal: excitation interference and NMR signal are always in phase with each other. Since often only the first data point (“echo”) is affected by excitation interference, it is customary to eliminate this first data point from the data set. The first data point, however, contains valuable information about fast time-dependent behavior of the NMR sample and therefore having to ignore this point is an unsatisfactory solution.
The method of the present invention, described in more detail below, uses a novel cycle of pulse sequences to reduce the effect of “excitation” interference, on the basis of changing the measurement frequency between certain pulse sequences. Naturally, the method is especially useful for NMR measurements in which small changes in frequency can readily be allowed or tolerated. For example, laboratory-type NMR machines typically operate in homogeneous fields with a single, well-defined frequency. Changes in frequency are employed either to follow fluctuations in the main magnetic field, or to enable magnetic resonance imaging (MRI). NMR machines built for wireline logging or similar industrial applications are much more robust with respect to small changes in frequency. Therefore, the proposed solution is well-suited for industrial NMR applications.
The method of the present invention uses prior art NMR apparatuses and logging tools to obtain previously unavailable data relating to the fast time-dependent behavior of an NMR sample. In particular, a novel pulse sequence is proposed and used to obtain improved NMR data by eliminating spurious signals corresponding to mechanical resonances in the measurement apparatus induced by the r.f. excitation pulse.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a method for improving the accuracy of borehole NMR logging measurements.
It is another object of the present invention to provide a method for improving the short time resolution of borehole NMR logging measurements.
It is yet another object of the present invention to provide a method for suppressing of magneto-acoustic artifacts in NMR data obtained from logging measurements.
These and other objects are accomplished in accordance with a preferred embodiment of the present invention by a novel cycle of pulse sequences and a data acquisition scheme that employ existing NMR logging instruments. The novel cycle of pulse sequences of the present invention is characterized by a change in the measurement frequency between pulse sequences. In a preferred embodiment of the present invention, the frequency change is chosen so that spurious signals induced by the excitation pulse may be significantly reduced by combining NMR signals from corresponding echoes received in response to each measurement frequencies.
In accordance with the present invention, one can determine petrophysical properties of a geologic formation more accurately by reducing the effect of spurious signals arising from the excitation pulse. In particular, significant errors in the first spin-echo are corrected in accordance with a preferred embodiment of the present invention, which therefore provides increased short time resolution and allows improved detection and quantification of components which are associated with short relaxation times such as clay-bound water. In turn, this more accurate measurement of the clay-bound water improves determination of the total porosity and use of the resistivity interpretation model.
More specifically, in a preferred embodiment of the present invention an NMR method for measuring attributes of a material is disclosed, comprising the steps of: (a) applying at least one first pulse-echo sequence having an associated measurement frequency F 1 ; (b) applying at least one second pulse-echo sequence having an associated measurement frequency F 2 different from F 1 ; (c) measuring NMR signals corresponding to the first pulse-echo sequence and the second pulse-echo sequence, these NMR signals representing spin-echo relaxation in the material, at least some of the measured NMR signals being corrupted by spurious signals; (d) combining measured NMR signals from the first pulse-echo sequence and from the second pulse-echo sequence to reduce the effect of said spurious signals; and (e) determining properties of the material on the basis of the combination of measured signals.
In another preferred embodiment of the present invention which is directed to borehole logging, a method for NMR borehole logging is disclosed, comprising the steps of: (a) providing at least one first pulse-echo sequence associated with a first measurement frequency F 1 ; (b) providing at least one second pulse-echo sequence associated with a second measurement frequency F 1 different from F 1 ; (c) measuring NMR signals corresponding to the first pulse-echo sequence and the second pulse-echo sequence, the NMR signals representing spin-echo relaxation of a geologic formation in the borehole, at least some of the measured NMR signals being corrupted by spurious signals; (d) combining measured NMR signals from the first pulse-echo sequence and from the second pulse-echo sequence to reduce the effect of said spurious signals; and (e) determining properties of the geologic formation in the borehole on the basis of the combination of measured signals.
BRIEF DESCRIPTION OF THE DRAWINGS
For the purposes of understanding the principles underlying this invention, reference is now made to the drawings, in which:
FIG. 1 is an illustration of a standard pulse sequence employed by NMR logging tools.
FIG. 2 is an illustration of a phase-alternated version of the standard sequence shown in FIG. 1 .
FIG. 3 illustrates the cycle of pulse sequences in accordance with a preferred embodiment of the present invention.
FIG. 4 is a standard field log illustrating curves from the first four data points from a phase-alternated CPMG sequence as a function of tool depth within a borehole.
FIG. 5 illustrates the results of a field test of the novel cycle of pulse sequences and data acquisition method in accordance with a preferred embodiment of the present invention.
FIG. 6 illustrates the increased resolution which enables detection and measurement of the clay-bound water content in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The principles underlying this invention are described below with a more specific reference to an embodiment which is directed to improved NMR borehole logging methods.
There are two versions of modern pulse-NMR logging tools in use today: the centralized MRIL® tool made by NUMAR Corporation, and the side-wall CMR tool made by Schlumberger. The MRIL® tool is described, for example, in U.S. Pat. No. 4,710,713 to Taicher et al. and in various other publications including: “Spin Echo Magnetic Resonance Logging: Porosity and Free Fluid Index Determination,” by Miller, Paltiel, Millen, Granot and Bouton, SPE 20561, 65th Annual Technical Conference of the SPE, New Orleans, La., Sep. 23-26, 1990; “Improved Log Quality With a Dual-Frequency Pulsed NMR Tool, ” by Chandler, Drack, Miller and Prammer, SPE 28365, 69th Annual Technical conference of the SPE, New Orleans, La., Sep. 25-28, 1994). Details of the structure and the use of the MRIL® tool are also discussed in U.S. Pat. Nos. 4,717,876; 7,717,877; 4,717,878; 5,212,447; 5,280,243; 5,309,098; 5,412,320; 5,517,115 and 5,557,200, all of which are commonly owned by the assignee of the present invention.
The Schlumberger CMR tool is described, for example, in U.S. Pat. Nos. 5,055,787 and 5,055,788 to Kleinberg et al. and further in “Novel NMR Apparatus for Investigating an External Sample,” by Kleinberg, Sezginer and Griffin, J. Magn. Reson. 97, 466-485, 1992.
The content of the above patents and publications is hereby expressly incorporated by reference. It should be understood that the present invention is equally applicable to both hardware configurations discussed above.
With reference to the attached drawings, FIG. 1 shows a standard pulse sequence typically employed by NMR logging tools, such as the Numar MRIL® and the Schlumberger CMR tools. As shown in FIG. 1, an excitation pulse (E x ) with radio frequency (r.f.) phase of zero degrees is first applied. An echo train follows, with a wait time of τ(tau) between the excitation pulse and the first refocusing pulse, and between the refocusing pulses (R y ) and the acquisition windows (A). The phase-alternated version of the standard CPMG sequence is depicted in FIG. 2 . This sequence is identical to the standard sequence, except that the refocusing pulses (R −y ) are 180 degrees out of phase, i.e., at a phase angle of minus 90 degrees with respect to the excitation pulse.
When the complex-valued NMR measurements acquired according to the standard and phase-alternated CPMG pulse sequences are added, the NMR signal is enhanced, and the interference arising from imperfect refocusing pulses is eliminated. This scheme does not however address problems associated with interference from the excitation pulse. In particular, the excitation pulse gives rise to microphonic interferences associated with mechanical resonances within the apparatus. These self-resonances occur within the measurement bandwidth but are not phase-locked to the NMR signal. These signals rather evolve with their intrinsic self-resonant frequency and exhibit a phase difference from the NMR signal that depends on the particular self-resonant frequency and the time delay between excitation and data acquisition. Typically, more than one self-resonance are located within the measurement bandwidth; their number and exact frequencies are in general unknown and also variable with time.
In accordance with a preferred embodiment of the present invention, a cycle of pulse sequences is applied, where the pulse sequences correspond to two or more frequencies. By alternating between at least two closely spaced NMR frequencies, the same resonances are excited. The phase difference between interference and NMR signal, however, evolves differently between excitation and data acquisition. specifically, if the frequency change is made equal to one-half of the time between excitation pulse and acquisition, an additional phase difference of 180 degrees is induced.
The novel cycle of pulse sequences in accordance with a preferred embodiment of the present invention is shown in FIG. 3 . The first pulse sequence in the cycle is identical to the one shown in FIG. 1, and the third pulse sequence is identical to the one shown in FIG. 2 . The second and fourth pulse sequences are applied at a different frequency from the first and third pulse sequences. Acquisition windows A ij correspond to the ith echo in the jth pulse sequence. In a preferred embodiment, the frequency difference is a function of the time delay between excitation pulse and data acquisition: F 1 - F 2 = 1 ( 4 τ ) . ( 1 )
where F 1 is the frequency at which the first and third pulse sequences are applied, F 2 is the frequency at which the second and fourth pulse sequences are applied, and τ is the constant delay time both between the excitation pulse and the first refocusing pulse and between the refocusing pulses and the acquisition windows.
In a more general case, the frequency difference in Eqn. (1) can be expressed as: F 1 - F 2 ≅ ( n + 1 2 ) 1 2 τ , (1A)
in which n is any integer or zero. It will be appreciated that for n=0, Eqn. (1A) is identical to Eqn. (1). However, generic Eqn. (1A) further indicates that due to the cyclic nature of the problem, a frequency difference corresponding to an additional offset of n/(2τ) will work also. Since keeping the frequency difference relatively small is desirable, however, it should be clear that the case in which n=0 is preferred.
Further, in accordance with a preferred embodiment of the present invention, data from all four measurements shown in FIG. 3 is added, which amplifies the NMR response and cancels both excitation and refocusing interference. In particular, data corresponding to the same acquisition slots are averaged using complex arithmetic:
A 1 =¼( A 11 +A 12 +A 13 +A 14 ), (2A)
A 2 =¼( A 21 +A 22 +A 23 +A 24 ), (2B)
A 3 =¼( A 31 +A 32 +A 33 +A 34 ), (2C)
. . . etc. . . , (2D)
where averaged acquisition A k corresponds to the kth slot in each pulse sequence. Equation 2D indicates that this method can be used for an unlimited string of acquisition slots: as shown in FIG. 3, the refocusing pulses and corresponding acquisitions are repeated for the full length of the pulse sequence. Equation 2D, then, indicates that averaged acquisitions A k may be obtained for all acquisition slots k, in this example for slots k>3.
Measurement parameters which may be used in a preferred embodiment of the present invention are shown in the following Table of optimum frequency differences for different pulse spacings.
Evolution Time:
Frequency
τ
(2τ)
Difference: (1/4τ)
0.50 ms
1.0 ms
500 Hz
0.25 ms
0.5 ms
1,000 Hz
NMR machines typically operate at frequencies between 1 MHz and 100 MHz; therefore the frequency changes in the above table are on the order of 0.1% to 0.001% of the Larmor or measurement frequency.
Results from field tests are illustrated in FIGS. 4 and 5. FIG. 4 is a standard field log which shows curves for the first four data points (echoes) from a phase-alternated CPMG sequence as a function of tool depth within the bore hole. Tool speed in this experiment was 5 ft/min, logging uphole. Every 3 seconds, the tool performed a CPMG pulse-echo sequence with 1,000 echoes and a pulse-to-pulse spacing of 0.51 msec. Four consecutive measurements were averaged. The operating frequency was 747 kHz. In this case, the first data point, marked as Track 1 in FIG. 4, is always abnormally high as a result of excitation interference.
FIG. 5 illustrates the results of a field test using the novel cycle of pulse sequences and data acquisition method of the present invention. The artifact which appears in FIG. 4 is corrected by invoking the frequency-cycling method of the present invention. For the measurement corresponding to FIG. 5, all parameters are were the same as that of FIG. 4, except that the operating frequency was alternated between 745 kHz and 746 kHz. Again, four consecutive measurements were averaged. Following the application of the ringing cancellation method of the present invention, the first data point, marked as Track 1 in FIG. 5, is shown to be correct.
Further results from field tests of the novel frequency-cycling method of the present invention are shown in Table 1. Data with pulse-to-pulse spacings (2τ) of 0.51, 0.6 and 1.2 ms were acquired, both with and without the novel cycle of the present invention. The interference effect on the first data point without the present invention was a misreading ranging from −2 to +3 percent of full scale. With data around 10 percent of full scale, these are errors of −20% to +30%. When the novel frequency-cycling method of the present invention is used, the systematic data error is reduced to an insignificant amount.
TABLE 1
Data Set
Frequencies
2τ
Comments
T1M
747 kHz
1.2
ms
first data points
questionable
T1R
747 kHz
1.2
ms
first data points
questionable
T1MAGM
747.00/747.42 kHz
1.2
ms
first data points clean
T1MAGR
747.00/747.42 kHz
1.2
ms
first data points clean
T2M
745 kHz
0.60
ms
first data points in error
T2R
745 kHz
0.60
ms
first data points in error
T2MAGM
744.60/745.40 kHz
0.60
ms
first data points clean
T2MAGR
744.60/745.40 kHz
0.60
ms
first data points clean
T3M
747 kHz
0.51
ms
first data points in error
T3R
745 kHz
0.51
ms
first data points in error
T3MAGM
745/746 kHz
0.51
ms
first data points clean
T3MAGR
745/746 kHz
0.51
ms
first data points clean
Applications
The MRIL® tool is capable of performing a variety of borehole NMR logging measurements the accuracy of which can be improved using the method of the present invention. See, for example, co-pending U.S. patent application Ser. No. 08/822,567, filed Mar. 19, 1997, file wrapper continuation of U.S. application Ser. No. 08/542,340 assigned to the assignee of the present application, which teaches systems and methods for lithology independent gas detection. U.S. patent application Ser. No. 08/816,395, assigned to the assignee of the present application and which was filed Mar. 13, 1997 claiming priority of provisional application Ser. No. 60/013,484, teaches, among other things, the use of a rapid-fire CPMG pulse sequence to detect and quantify components having very short relaxation times, such as clay-bound water. The content of the above patent applications is hereby expressly incorporated by reference. These and other NMR measurement methods using the MRIL® tool, as well as measurement methods using the Schlumberger CMR tool, can be improved when performed in conjunction with the method of the present invention.
In particular, as indicated above, the first echo in a CPMG echo train with echo spacing 0.51, 0.60 or 1.2 ms can be corrected using the method of the present invention. Data from the uncorrected echo trains is inaccurate for times shorter than 1.02, 1.2 or 2.4 ms, respectively because the first echo can not be used. The elimination of excitation interference clearly increases the spin-echo relaxation time resolution of the NMR measurement. For example, clay-bound water has spin-echo relaxation times on the order of 1 ms. Because of the corruption of the first data point, prior art methods were incapable of measuring relaxation signals of this order. As shown in FIG. 6, the increase in resolution using the method of the present invention enables one to not only detect but also measure the quantify of the clay-bound water component that is a contributing factor, for example, in total porosity measurements. This newly provided capability improves the utility and the accuracy of the measurements obtained using standard NMR tools.
Although the present invention has been described in connection with a preferred embodiment, it is not intended to be limited to the specific form set forth herein, but is intended to cover such modifications, alternatives, and equivalents as can reasonably be included within the spirit and scope of the invention as defined by the following claims. | Novel pulse sequence and data acquisition method are disclosed which eliminate the effects of spurious NMR signals caused by mechanical resonances within the measurement apparatus. The proposed method alleviates interference problems typically arising from strong “excitation” pulses in a sequence, and enables the use of the corresponding data points to increase the resolution of the measurement. The method is based on changing the measurement frequency between pulse sequences and averaging out data points obtained from the different sequences in a way that effectuates cancellation of the spurious signals. The novel cycle of ulse sequences and a data acquisition method can be used, or example, with any existing NMR logging instruments. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of prior U.S. patent application Ser. No. 10/035,766 filed on Dec. 26, 2001 entitled “GATED ELECTRON EMITTER HAVING SUPPORTED GATE,” which is incorporated herein by reference in its entirety for all purposes.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a device for field emission of electrons. More particularly, apparatus and method for manufacture are provided for a field emitter having a mechanically supported extraction gate. Field emission is a well-known effect in which electrons are induced to leave a cathode material by a strong electric field. The electric field is formed by a grid or gate electrode in proximity to a tip or protrusion of the cathode material. A common problem with field emission devices fabricated with grids or gates in close proximity to a tip of cathode material is that an electrical short-circuit may develop along the surface of the insulator layer between the gate and the cathode, which can render the device inoperable. To alleviate the problem, field emission devices have utilized multiple layers of insulator material between the cathode and gate or grid to increase the path length along the surfaces between the gate and cathode. U.S. Pat. No. 6,181,060B1 discloses multiple dielectric layers between the grid and cathode that are selectively etched to form a fin of the less etchable dielectric. The fin increases the path length for electrons along the surfaces between the grid and cathode, thus reducing leakage and increasing the breakdown voltage.
[0003] Dielectric layers between the gate and cathode have been undercut to produce field emission cathodes having decreased electrical capacitance. Undercutting refers to the process of removing all or most of the material surrounding a majority of the tips, leaving cavities that encompass multiple tips. A problem with cavities is the deflection of the gate layer above the cavity due to electrostatic or mechanical forces. In order to minimize gate deflection over cavities, U.S. Pat. No. 5,589,728 discloses pillars or post supports spaced throughout the cavities that directly support the gate layer but leave the gate layer unsupported between the pillars or posts. Effective gate support with only pillars and such supports reduces overall emission tip density because the pillars are spaced closely and utilize space where tips could otherwise be located. A lower overall emission tip density can require a larger emission device to produce similar electron emission. Such a device may be too large for utilization in products such as CRTs or electron guns.
[0004] Accordingly, a need exists for an improved gated electron emitting device. Such device should provide higher current and current density and have longer lifetime than prior art devices. Preferably, the device should be produced inexpensively utilizing conventional semiconductor fabrication processes.
SUMMARY OF THE INVENTION
[0005] A gated field emission device with a dielectric support layer that supports the gate electrode over an opening or cavity around one or more emission tips is provided. In one embodiment, multiple layers of dielectric with cavities between the layers and a dielectric support layer that supports the gate electrode are provided. In yet another embodiment, field emission apparatus utilizing support structures such as posts or walls in contact with the support layer are provided. A cover layer of dielectric may be used over the gate layer. Emitter tips may be carbon-based. Methods for making the device using known processing steps are provided.
[0006] The foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.
DESCRIPTION OF THE FIGURES
[0007] The present invention is illustrated by way of example and not limitation in the accompanying figures.
[0008] FIG. 1 includes an illustration of a portion of a silicon substrate with a template for forming mold indentions in the silicon.
[0009] FIG. 2 includes an illustration of a cross-sectional view of a portion of the silicon substrate of FIG. 1 after the template is removed and an emission layer is formed over the silicon substrate and emission tips are formed in mold indentions.
[0010] FIG. 3 includes an illustration of a cross-sectional view of a portion of the emission layer with emission tips of FIG. 2 after the mold is removed and a first layer, support layer, gate layer, and photoresist have been formed over the emission layer.
[0011] FIG. 4 includes an illustration of a cross-sectional view of a portion of the emission layer with emission tips of FIG. 3 where a portion of the photoresist above the emission tips has been etched to expose a portion of the gate layer.
[0012] FIG. 5 includes an illustration of a cross-sectional view of a portion of the emission layer with emission tips of FIG. 4 after etching a portion of the gate layer above the emission tips to expose a portion of the support layer.
[0013] FIG. 6 includes an illustration of a cross-sectional view of a portion of the emission layer with emission tips of FIG. 5 after etching a portion of the support layer above the emission tips to expose a portion of the first layer.
[0014] FIG. 7 includes an illustration of a cross-sectional view of a portion of the emission layer with emission tips of FIG. 6 after etching the first layer to form cavities surrounding individual emission tips.
[0015] FIG. 8 includes an illustration of a cross-sectional view of a portion of the emission layer with emission tips of FIG. 7 after etching the first layer to form a cavity surrounding multiple emission tips.
[0016] FIG. 9 includes an illustration of a top view of a silicon substrate masked to define support walls and emission tips.
[0017] FIG. 10 includes an illustration of a cross-sectional view of a portion of an emission layer with emission tips after the first layer has been etched to define a support wall.
[0018] FIG. 11 includes an illustration of a top view of a silicon substrate masked to define support pillars and emission tips.
[0019] FIG. 12 includes an illustration of a cross-sectional of a portion of an emission layer with emission tips after a first layer, first intermediate layer, second intermediate layer, support layer, and gate layer have been formed over the emission layer and emission tips.
[0020] FIG. 13 includes an illustration of a cross-sectional view of a portion of the emission layer with emission tips of FIG. 12 after the gate layer and support layer have been etched to define openings above the emission tips and the second intermediate layer has been etched to define a cavity surrounding multiple emission tips.
[0021] FIG. 14 includes an illustration of a cross-sectional view of a portion of the. emission layer with emission tips of FIG. 13 after the first intermediate layer has been etched to define openings above the emission tips and the first layer has been etched to define cavities surrounding individual emission tips.
[0022] FIG. 15 includes an illustration of a cross-sectional view of a portion of a gate layer after a layer has been formed over the gate layer and openings have been etched in the layer and gate layer.
[0023] Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of embodiments of the present invention.
DETAILED DESCRIPTION
[0024] Reference is now made in detail to the exemplary 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 (elements).
[0025] FIG. 1 illustrates a portion of mold 10 that may be produced using common photolithographic techniques. Initially, thin silicon oxide, silicon nitride, or other similar film 12 can be grown on the surface of silicon wafer 14 . A template may be created by etching a plurality of openings 16 in the oxide film using conventional photolithographic processes. The openings may be in the shape of squares or circles. The openings may be in the range of about 2 microns per side and can be arranged in groups such that each group forms an array having a selected number of squares, such as group 18 . Mold 10 may consist of a plurality of groups. After the openings are defined in the template, the mold can be anisotropically etched in potassium hydroxide to form indentations or pits in the silicon. The pits may be in the shape of inverted pyramids. The template may be removed using common processes.
[0026] Emission layer 20 may be formed over the mold as shown in FIG. 2 . Emission layer 20 may comprise a carbon-based film formed by placing mold 10 in a conventional diamond growth reactor. Common growth conditions may be used to form a carbon-based film, such as disclosed in U.S. Pat. No. 6,181,055B1, which is incorporated by reference herein. Such films may contain a mixture of sp2 and sp3 carbon bonds, and are sometimes referred to as “diamond” and sometimes “carbon-based.” The growth of carbon-based material into mold indentions 22 results in tips 24 that can be used as emitters. Other materials having electron-emitting properties may be used. Molded tips 24 can be pyramidal. Emission layer 20 may be grown to a thickness greater than the height of mold indentions 22 to ensure complete formation of tips 24 , and generally may have a thickness in the range of approximately 2-5 microns. Emission layer 20 usually will be less than 400 microns thick.
[0027] Silicon wafer 14 can be removed from the carbon-based material using well-known techniques, leaving molded carbon-based emitter tips 24 supported by emission layer 20 or other supportive material, as shown in FIG. 3 . First dielectric layer 30 may be formed over tips 24 and emission layer 20 using techniques such as sputtering or chemical vapor deposition. Next, dielectric support layer 32 may be formed over first layer 30 . First layer 30 may be silicon dioxide (SiO 2 ) or other dielectric material and support layer 32 may be silicon nitride (Si 3 N 4 ), a stable form of silicon dioxide, or other dielectric material that allows layer 30 to be selectively etched relative to support layer 32 . That is, first layer 30 should be etched at a faster rate than support layer 32 when a selected etchant is used. More than two dielectric layers that etch at different rates with selected etchants may be used. The combined thickness of first layer 30 and support layer 32 may be in the range of approximately 0.5-3 microns. First layer 30 and support layer 32 can have a ratio of thickness of approximately one, but may have large deviations from this ratio. The support layer should be thick enough to provide needed mechanical strength for gate layer 34 , which generally can be provided when the thickness of support layer 32 is in the range of 0.5-3 micron.
[0028] Still referring to FIG. 3 , gate layer 34 may be formed by sputtering or evaporating molybdenum or a similarly conductive and reactive material over support layer 32 . Gate layer 34 may have a thickness in the range of approximately 0.1-0.8 microns. Photoresist 36 can be spun onto gate layer 34 such that photoresist 36 over tips 24 is thinner than between tips 24 . Next, photoresist 36 may be ion etched with oxygen or another similarly reactive etchant to remove photoresist 36 over tips 24 . This etching should expose gate layer 34 over tips 24 , as shown in FIG. 4 .
[0029] Illustrated in FIG. 5 , gate layer 34 may be reactive ion etched with carbon tetrafluoride (CF 4 ), sulfur hexafluoride (SF 6 ), or another similarly reactive chemical to expose support layer 32 over tips 24 . Remaining photoresist can be removed using common processes, leaving gate layer 34 exposed as illustrated in FIG. 6 . Support layer 32 can be further reactive ion etched to form an opening in layer 32 and to expose first layer 30 through that opening, as shown in FIG. 6 . The opening in support layer 32 should be equal in size or smaller than the opening in gate layer 34 .
[0030] First layer 30 can be wet etched back from tips 24 , using a buffered hydrofluoric acid or another similarly reactive etchant. FIG. 7 illustrates the result. Cavity 70 can be formed in first layer 30 around each tip 24 . A portion of support layer 32 is left to protect and support gate layer 34 . The resulting structure of FIG. 7 increases the surface breakdown path length, mechanically supports gate layer 34 and protects gate layer 34 from evolving tip material. As a result, leakage current between gate layer 34 and emitter tips 24 will be reduced significantly.
[0031] In another embodiment, first dielectric layer 30 is completely etched away from most of the tips 24 , as illustrated in FIG. 8 . This etching step creates cavity 80 around and between multiple tips 24 . Support layer 32 is more resistant to the etchant used on first layer 30 , such that support layer 32 remains intact and supports gate layer 34 .
[0032] Spaced support structure may be provided for support layer 32 when cavity 80 is large. Dielectric support walls may be formed in an emitter tip array by creating gaps 90 between tip indentions 92 in an initial mold 94 , as illustrated in FIG. 9 . Gaps 90 and tip indentions 92 may be created in mold 94 using common lithographic techniques. If the gaps are sufficiently wide, for example having a width greater than the tip-to-tip distance 102 ( FIG. 10 ), support wall 100 may remain after layers surrounding the tips are etched as described above. Support wall 100 can be located in the range of 30-70 microns from other support walls or structures, for example. Support walls may be formed in emitter arrays using more than two dielectric layers between an emission layer and a gate layer.
[0033] Alternatively, support pillars can be formed in a final emitter tip array by creating gaps 110 amongst tip indentions 92 in the initial mold 94 , as illustrated in FIG. 11 . Gaps 110 and tip indentions 92 may be created in mold 94 using common lithographic techniques. If the gaps are sufficiently large, for example having a width greater than the tip-to-tip distance 102 , support pillar 110 may remain after layers surrounding the tips are etched as described above. Support pillars can be located 30-70 microns from other supporting pillars or structures, for example. Support pillars may be formed in emitter arrays using multiple dielectric layers between an emission layer and support layer.
[0034] In yet another embodiment, illustrated in FIG. 12 , multiple layers may be formed between emission layer 20 and support layer 32 . The additional layers can be formed as previously described, utilizing conventional deposition methods such as sputtering or chemical vapor deposition. Additional layers may also be etched to define openings as described above using common etch techniques such as wet etching, dry etching, and reactive ion etching. Methods of forming support structures described earlier may be used with multiple layers located between an emission layer and gate layer.
[0035] In a particular embodiment, first etch layer 31 , which may be a dielectric or a conductor, as shown in FIG. 12 , may be formed over emission layer 20 and tips 24 . First etch layer 31 may comprise aluminum or a dielectric etchable material and can be formed through sputter deposition or other common techniques. First intermediate dielectric layer 120 may be formed over first etch layer 31 and may comprise silicon nitride, a stable silicon dioxide, or other dielectric material that is capable of being selectively etched in relation to first etch layer 31 or layers formed later in time. First intermediate dielectric layer 120 may have a thickness in the range from about 0.1 to about 0.7 micron, for example. Second intermediate dielectric layer 122 can be formed over first intermediate dielectric layer 120 and may comprise silicon dioxide or other dielectric material that is capable of being selectively etched in relation to first etch layer 31 , first intermediate dielectric layer 120 , or layers formed later in time. The second intermediate dielectric layer may have a thickness in the range from about 0.5 to about 1.5 micron, for example. Support layer 32 is formed over the second intermediate layer and may comprise silicon nitride, a stable silicon dioxide, or other dielectric material that may be selectively etched in relation to first etch layer 31 , first intermediate dielectric layer 120 , second intermediate dielectric layer 122 , or layers formed later in time. First intermediate dielectric layer 120 , second intermediate dielectric layer 122 , and support layer 32 can be formed through chemical vapor deposition or other conventional methods. Gate layer 34 may be formed over the support layer as described above. Preferably, all of these layers may each have a total thickness in the range of about 0.5-3 micron, but other values of thickness can also be used.
[0036] Photoresist can be applied and gate layer 34 and support layer 32 may be etched as described above to form an opening in layer 32 and to expose second intermediate dielectric layer 122 through that opening. The opening in support layer 32 should be equal in size or smaller in size than the opening in gate 34 . A wet etch, such as buffered hydrofluoric acid or another similarly reactive chemical, may then be used to etch second intermediate dielectric layer 122 between support layer 32 and first intermediate dielectric layer 120 to form cavity 130 between support layer 32 and first intermediate layer 120 , illustrated in FIG. 13 . A reactive ion etch, as described above, can then etch first intermediate layer 120 to expose first etch layer 31 . A wet etchant, such as phosphoric acid or another similarly reactive chemical, can be used to remove first etch layer 31 from tips 24 resulting in the structure illustrated in FIG. 14 . First etch layer 31 may be etched completely away from most tips 24 to form a cavity (not shown).
[0037] Another embodiment may include cover layer 150 formed over gate layer 34 , illustrated in FIG. 15 . Layer 150 may be made of silicon dioxide, silicon nitride, or other dielectric material that may be selectively etched in relation to underlying layers. Layer 150 can be formed using chemical vapor deposition or other conventional methods and may have a thickness in the range from about 0.1 to about 0.9 micron. Layer 150 can provide additional stiffness to gate layer 34 and further protection against electrical shorts. Embodiments incorporating layer 150 may be processed as described above to define openings, cavities, and support structures. Multiple layers may be formed between gate layer 34 and layer 150 , or over layer 150 using common processes.
[0038] The field emission arrays disclosed herein exhibit more reliable operation and longer lifetimes than field emission arrays of the prior art. Deflection of the gate layer over cavities is eliminated or substantially reduced. The support layer allows fewer supports such as pillars or walls, and thus makes possible greater emission tip density and hence greater emission current density.
[0039] In the foregoing specification, the invention has been described with reference to specific embodiments. However, after reading this specification, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. | A field emission device having emitter tips and a support layer for a gate electrode is provided. Openings in the support layer and the gate layer are sized to provide mechanical support for the gate electrode. Cavities may be formed and mechanically supported by walls between cavities or columns within a cavity. Dielectric layers having openings of different sizes between the emission tips and the gate electrode can decrease leakage current between emitter tips and the gate layer. The emitter tips may comprise a carbon-based material. The device can be formed using processing operations similar to those used in conventional semiconductor device manufacturing. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to a process for preparing aqueous dispersions of rosin-base materials, and more particularly to a process for preparing aqueous dispersed size of enhanced alum sensitivity and lowered tendency to foam.
Cellulose fiber products such as paper and paperboards are produced from an aqueous slurry, or furnish, of cellulose fibers containing sizing agents admixed therewith. These sizing agents generally comprise aqueous dispersions of rosin, especially fortified rosin, which is utilized to modify the surface of the paper to control water penetration. Such sizing is termed internal sizing and is an important step in the wet end operation of a paper machine.
Rosin, or rosin acid, itself has no affinity for cellulose fiber and must be anchored to the surface of the cellulose fiber with a cation such as an aluminum ion normally derived from alum. The rosin acid size and aluminum ions do not react in solution but are codeposited on the fiber surface. The size is held on the pulp fiber by electrostatic forces. This rosin acid size is not yet hydrophobic, but it becomes water-repellent after interaction with the alum in a subsequent heat curing step. The curing occurs when rosin size melts in the drier section of the paper machine and the molten rosin acid spreads over the fiber surface and reacts with neighboring alum adsorbed on it. The resulting aluminum-rosinate is to a large extent responsible for the degree of water repellency of the paper product.
Attention is directed to the disclosures of related U.S. Pat. Nos. 4,267,099 and 4,309,338 to Okumichi et al for an in depth discussion of a method of preparing a dispersed rosin size by the inversion method, which patents are incorporated by reference herein.
Okumichi et al provide a process for preparing an aqueous dispersion of a rosin-base material by the inversion method characterized by reduced foaming properties achieved by use of at least one of the dispersants disclosed and claimed therein. While dispersed rosin size prepared in accordance with Okumichi et al and particularly sizes produced with a dispersant selected from the salts of sulfuric acid half ester of formula II of U.S. Pat. No. 4,267,099, referred to by Okumichi et al as "sulfates," provides dispersed rosin size of reduced foaming properties, the size still tends to produce excessive foam under conditions normally encountered in some papermaking machines.
Okumichi et al thus approached the problem of lowering the tendency of a dispersed rosin size to foam by specifically tailoring the dispersant, or surfactant, albeit they do recognize the obvious expedient of lowering the surfactant level in the size to lower the tendency of the size to foam. Unfortunately, a simple lowering of surfactant level is not practicable because surfactant level is tied to the very ability to produce a dispersion.
Attempts to lower foam generation with dispersed rosin size such as disclosed by Okumichi et al and having a lowered level of the salts of the sulfuric acid half ester of formula II of U.S. Pat. No. 4,267,099 to Okumichi et al, even with the addition of cosurfactants has generally not met with success. Along the same lines, the effect of increased rosin fortification was studied and no appreciable effect on foam generation was noted. However, a detrimental effect on size particle dimension was noted, i.e. the particle size was increased wherein desirable product qualities were compromised without appreciable decrease in foam.
Kawatani et al, in Japanese Kokai No. 79 58, 759, provide another approach to lowering the tendency of aqueous rosin dispersions to foam through the use of internal foam depressors. Kawatani et al teach the use of simple aliphatic acids, e.g., caproic, caprylic, lauric, or myristic, for this purpose. This method of foam lowering is unappealing because the amount of rosin available for sizing is reduced, contaminates with unknown effects are introduced, and the basic problem of inefficient surfactant usage is neglected.
It is known that rosin itself has no affinity for cellulose fiber and is generally anchored to the surface of fiber by utilization of alum. Between pH 4.7 and 5.0, complex polymolecular forms of aluminum ions have been found to be prevalent in a paper making furnish containing alum. This complex Al 8 (OH) 20 4+ is highly charged and its OH groups can easily interact with the COOH groups from rosin or cellulose. Adsorption of aluminum on fiber rapidly increases in the pH region where the aluminum complex species is formed.
Thus, a need still exists for a dispersed rosin size of reduced foaming tendency and enhanced alum sensitivity.
SUMMARY OF THE INVENTION
In the practice of the present invention a cosurfactant and optional inorganic salt are disclosed for their efficacy in lowering foam in aqueous dispersed rosin size and enhancing the alum sensitivity of the size. The terminology "alum sensitivity" will be understood to define a measure of the physio-chemical propensity for alum to be well distributed on the furnish fibers to enable the subsequent production of a rosin size precipitate, i.e., aluminum rosinate, in situ, on the furnish fiber surface by interaction of dispersed rosin size particles and alum during a subsequent step of heat curing the paper web. The practice of the present invention enables the provision of dispersed rosin size showing less foaming tendency with relatively little loss of other desirable properties, particularly sizing efficiency, as well as mechanical or shear stability, and settling stability of the rosin size during handling and storage. The improved reduced foam characteristics and enhanced alum sensitivity of dispersed rosin size produced in accordance with this invention are also evident from a consideration of the nature of the foam itself, i.e., the foam bubbles tend to be larger and more easily broken, which effect may in the final analysis be more important than absolute foam level.
With the foregoing in mind it will be appreciated that the principal object of the present invention is the provision of a process for favorably influencing the precipitation of size with alum while lowering the tendency for dispersed rosin size to foam with as little loss of other desirable properties.
It is further another object of the present invention to increase the sensitivity to alum and reduce the susceptibility to foaming of aqueous dispersions of rosin-base material generally prepared in accordance with the teaching of Okumichi et al U.S. Pat. No. 4,267,099 incorporated herein, and particularly dispersions produced in accordance therewith utilizing the "sulfates" of formula II of the patent through use of a cosurfactant and optionally an inorganic salt.
It is a further object to provide for enhanced alum sensitivity and foam lowering in dispersed rosin size by the utilization of dioctyl sodium sulfosuccinate as a cosurfactant in dispersed rosin size utilizing as primary surfactants the sulfates of formula II of U.S. Pat. No. 4,267,099.
The cosurfactant is added in an amount sufficient to lower the foaming tendency of the aqueous dispersion and increase the sensitivity of the size to alum to provide an attendant increase in sizing efficiency. When the surfactant level is in the preferred range of from about 3.0% to about 3.5% by weight of the rosin-base material, the cosurfactant is added in an amount from about 1.0% to about 3.0% by weight of the rosin-base material. Also, within the preferred surfactant range, the optional inorganic salt can be added in an amount up to about 0.1% by weight of the rosin-base material. When the surfactant level is in the most preferred range of about 3.5% by weight of the rosin-base material, the inorganic salt level is preferably from about 0.04% to about 0.055% by weight of the rosin-base material.
It is another object of this invention to provide a process wherein the level of foam generation in dispersed rosin size, in a dynamic system such as a sizing step in a paper mill, is minimized, or equally as importantly the rate of foam generation is reduced.
A further object of this invention is the provision of a process wherein the deposit of rosin on papermaking machinery can be reduced by enhancing the deposition of the dispersed rosin in or on the paper web.
Still a further object of the present invention is to provide a process wherein the stability to settling, or mechanical stability, of dispersed rosin size is not significantly impaired as a result of the incorporation of foam reducing additives.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The teaching of Okumichi et al of a process for preparing, by an inversion method, size comprising an aqueous dispersion of rosin-base materials which are improved in accordance with the invention disclosd in copending application Ser. No. 487,338 filed Apr. 21, 1983, which is also herein incorporated by reference for a disclosure of the optional step in the present invention of the addition of a inorganic salt to the dispersant or surfactant "sulfates" of formula II as disclosed and claimed in the U.S. Pat. No. 4,267,099.
Reference is made to U.S. Pat. No. 4,071,375 for a disclosure of fortified rosins as well as a process for their preparation. Reference is made to U.S. Pat. Nos. 2,028,091 and 2,176,423 for a disclosure of the dioctyl sodium sulfosuccinate cosurfactant utilized in carrying forth the present invention.
Dispersed size for tests for quantification of alum sensitivity was produced on a laboratory scale by the following procedure, it being understood that the rosin fortification procedure is not set forth and in this latter regard, the disclosure of U.S. Pat. No. 4,071,375 may be referred to for a known procedure for fortification of rosin such as with fumaric acid. 600 g fortified rosin is charged into a 2 liter resin kettle and the rosin is heated to a temperature of about 165° C. and then cooled to a temperature of about 135° C. and maintained at such temperature for a minimum of five minutes before adding surfactant, or surfactant-salt in those instances where an inorganic salt such as aluminum nitrate, is used in conjunction with the surfactant. When surfactant-salt is utilized, it is prepared by diluting an amount of surfactant corresponding to the desired percentage level relative to the rosin, by weight, which surfactant is then diluted to in the order of about 18% solids. The salt, when utilized, is added to the dilute surfactant and the surfactant added slowly to the rosin in the kettle such as at a rate in the order of 6 ml per minute. The temperature in the kettle normally will drop below 100° C. during this addition and a temperature in the order of about 97°-99° C. should be maintained throughout addition of all surfactants. After all surfactant or surfactant-salt has been incorporated, the mixture is stirred for thirty minutes while maintaining the temperature in the order of about 97°-99° C., after which water addition is commenced. In the first water addition, 65°-95° C. water is added at the rate of 6 ml per minute to adjust the solids to 75%. Stirring of the mixture is then continued for thirty minutes while maintaining the temperature in the order of about 97°-99° C. A second addition of water is then commenced at a slightly faster rate in the order of about 10 ml per minute to adjust the solids content to about 47% while maintaining the temperature in the order of about 97°-99° C. It will be noted that inversion occurs approximately two thirds of the way through this second addition and a temperature decrease of about 1° C. will be observed at the point of inversion. After the second addition of water is completed, the mantle is dropped and all heat to the kettle is cut off. The dispersion in the kettle is allowed to cool to below 60° C. before the addition of a third aliquot of water which water at a temperature in a range of 20° to 35° C. is added at a rate in the order of about 22 ml per minute to adjust the dispersion to 35% solids.
When inorganic salts are employed, they are reagent grade material and are commercially available hydrates. Distilled water was employed unless otherwise specified. Rosin adducts were either produced in the laboratory or pilot plant generally as set forth in the above discussed procedure, or were plant produced commercially available materials where set forth. Particle diameters and sigmas reported were determined using a Nicomp Laser Light scattering instrument.
The principal surfactants employed are those in accordance with the dispersants disclosed and claimed in U.S. Pat. No. 4,267,099 as being selected from the group consisting of (b): ##STR1## wherein R 2 is hydrogen or lower alkyl, A is straight-chain or branched-chain alkylene having 2 to 3 carbon atoms, p is an integer of 4 to 25, and Q is a monovalent cation. More specifically, the surfactant in accordance with U.S. Pat. No. 4,267,099 utilized comprises formula II of the patent wherein R 2 is hydrogen and A is a branched-chain alkylene having 3 carbon atoms, p is 13 and Q is a monovalent cation, for example, lithium, sodium, potassium, cesium and like alkali metal ions, ammonium ions derived from ammonia and amines, etc. It will be appreciated that all surfactants within the scope of formula II of U.S. Pat. No. 4,267,099 are suitable for carrying forth the present invention.
The required amount of the optional appropriate salt, based on weight of rosin, is dissolved in a minimum amount of water and added to undiluted surfactant. The surfactant is further diluted to 18% solids. When preparing a dispersion wherein 0.044% aluminum nitrate is used with 600 gms rosin, 0.264 gms aluminum nitrate monohydrate is dissolved in 25 ml water. The water is considered part of the surfactant dilution water and added directly to the undiluted surfactant.
In the examples to follow the dispersed rosin size was prepared according to the method just described which is according to the disclosures incorporated herein.
EXAMPLES 1-5
Dioctyl sodium sulfosuccinate DSS, is disclosed herein as comprising a cosurfactant capable of increasing alum sensitivity in addition to assisting in reducing foaming. In Table I Examples 1 through 5 provide comparisons of dispersed rosin size both with no cosurfactant and at various cosurfactant levels.
Various methods of addition of the DSS to the dispersed rosin size were used and it is observed that there does not appear to be a preferred method or point in time of addition as long as the DSS is intimately admixed throughout the size.
TABLE I______________________________________FOAM GENERATION WITH SIZECONTAINING COSURFACTANTS Dynamic Dynamic DrainageSur- Drainage Jarfact- Jar Foam Foamant Cosurfactant Test** Test**Level Level Standard* (No. (withEx. % Type % Foam test CaCO.sub.3 CaCO.sub.3______________________________________1 3.5 -- 0 20/10/0 450 550 Out Top S S C 30 M/D in 20 secs2 3.5 DSS 1 25/15/0 450 550 475 550 S S C 42 M/D 5 M-L/D3 3.5 DSS 3 30/15/0 425 450 Out Top S S C 24 M-L/D in 40 secs4 3.0 DSS 1.0 30/15/0 -- -- 500 425 S S C 4 M-L/D5 3.0 DSS 1.5 25/10/0 -- -- Out Top S S C in 25 Secs______________________________________ *Standard foam results are reported as first line: highest foam in mls/foam after 30 seconds/foam 30 seconds after completion; second line: bubble size/bubble size (Small, Medium or Large)/breakdown charateristics (Complete, Partial, Unbroken). **Dyanamic drainage jar (DDJ) foam results are reported in the folowing manner: number in upper left corner equals height of foam in mls at one minute; upper right corner equals maxium foam height; lower left corner i breakdown time in seconds, lower right is bubble size (Small, Medium, or Large) and presence of a deposit on cylinder walls (D). "Out Top" refers to foam generation out the top of the graduated cylinder.
EXAMPLES 6 AND 7
These Examples show that the addition of sodium dioctylsulfosuccinate (DSS) to the invention's dispersed rosin size increases the alum sensitivity of the size by five-fold, which results in an increase in sizing efficiency in the order of 10% or more, as shown in Table II.
TABLE II______________________________________Cosur- Rosin Adduct Alum SensitivityEx. factant fumaric/formaldehyde (milliliters to precipitation)______________________________________6 none 9.5 1 207 DDS 9.5 1 4______________________________________
In this test size is titrated with dilute alum solution. The same effect can be demonstrated by adding alum (greater than 1 molar equivalent) to a dilute sample of size. The mixture is stirred and filtered. The untreated size produces a cloudy filtrate from which additional rosin may be recovered. The size with the DSS added, on the other hand, filters cleanly, and no rosin is contained in the filtrate. The principal benefit is that sizing efficiency increases. An additional benefit derived from improved sizing is that rosin deposits on papermaking machinery such as in the press section which have been attributed to build up of rosin particles can be reduced by modifying size in accordance with this invention to insure deposition of a majority of the dispersed rosin size in the paper web.
Mixtures of 50/50 hardwood/softwood pulp were used for these handsheet tests. The pulp was beaten to 75 seconds Williams slowness and treated with 20 pounds/ton alum and 8 pounds/ton size. Sodium hydroxide was used to adjust pH to 4.5 after alum addition. The first four samples were run with baled pulp, the last two in never-dried pulp.
EXAMPLES 8-19
The increased alum sensitivity effect on sizing efficiency was determined by handsheet studies performed on sizes with and without DSS. These sizes had been made with several different fortified rosins. The results are shown in Table III.
TABLE III______________________________________SIZING WITH DISPERSED SIZECONTAINING DSS AS COSURFACTANT Rosin Adduct Primary Hercules fumaric/ Surfactant DDS Size Test*Ex. formaldehyde Level (%) Level (%) (Seconds)______________________________________ 8 9.5 1 4.5 0 183.6 ± 18.7 9 9.5 1 4.5 1 249.8 ± 22.310 9.5 1 4.5 0 134 ± 15.611 9.5 1 4.5 1 156 ± 9.912 9.5 1 3.5 0 153 ± 23.313 9.5 1 3.5 1 231 ± 28.814 9.5 1 3.5 0 187 ± 12.2215 9.5 1 3.5 1 222 ± 18.816 9.5 1 4.5 0 131.8 ± 1617 9.5 1 4.5 1 161.1 ± 15.318 10 1 4.5 0 186 ± 10.4 (Plant Batch)19 10 1 4.5 1 213 ± 19.9 (Plant Batch)______________________________________ *Standard test for measuring penetration of ink through paper.
The results show longer penetration times for handsheets treated with DDS-containing size which indicate that DSS increases sizing efficiency in handsheets.
Dispersed rosin size with DSS has the following properties: sizing efficiency seems to be increased in handsheets; alum sensitivity is increased without affecting hard water stability, foaming tendencies are reduced somewhat, although air entrainment is not dramatically improved, and mechanical stability and particle size are retained. The use of DSS as a cosurfactant thus results in an improvement over size without this cosurfactant. Lowering the amount of primary surfactant seems not to improve foaming particularly when DSS is used; and therefore, DSS can be used as a cofactor in place of an inorganic salt such as aluminum nitrate for certain applications.
For example, in a mill situation where deposits of size-containing material may accumulate on a doctor blade at press rolls, this may result from size reacting too slowly with alum and not being bound completely into the web permitting a small portion of the later precipitating material finding its way to the doctor blade. Improved sensitivity of the size to alum would help alleviate this situation. | A sulfonated dicarboxylic acid is disclosed as a cosurfactant for its efficacy in lowering foam in alum-containing aqueous dispersed rosin size, and particularly in calcium-containing dispersed rosin size systems. The sulfonated dicarboxylic acid additive also enhances alum sensitivity of the dispersed rosin size. The addition of dioctyl sodium sulfosuccinate, DSS, cosurfactant to a salt of sulfuric acid half ester surfactant-containing dispersed rosin size lowers the tendency for foaming and increases the sensitivity of the size to alum with an attendant increase in sizing efficiency. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of our earlier application, Ser. No. 924,854, filed July 17, 1978 and now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to systems for receiving and evaluating empty beverage containers of a type known in the trade as returnable. These are containers, usually glass bottles, for which the beverage purchaser is charged a deposit fee at the time of purchase. When the purchaser returns the empty container to a designated redemption center, the deposit fee is refunded. Most beverage sales outlets also operate redemption centers, and the operation of these centers is usually a troublesome matter which takes clerks away from other more profitable tasks.
Beverages are commonly sold in containers of many different sizes, and in cartons containing groups of six or eight such containers. The customer may return the containers either individually or in cartons and may mix different types of containers in a single carton. It is the task of the redemption center clerk to sort or classify the containers in accordance with their deposit values and to calculate the refund which is due. The clerk may make an actual refund or may give the customer a refund slip which can be redeemed at another location. This operation is so unprofitable that many supermarkets simply operate on an honor system, whereby customers stack their empties at a receiving location and report the return to a checkout clerk, who makes the appropriate refund.
An alternative to the above described redemption techniques is an automatic system such as a system of the type described in Planke U.S. Pat. No. 3,955,179. This system has a pair of conveyors, one for individual empty bottles and one for cartons. In operation the customer places the returned bottles and cartons on the appropriate conveyor for transportation through an illumination station. At the illumination station the containers are illuminated by a beam of collimated light, and a shadow of the containers is projected against an array of photodetectors. The containers are identified by their shadows. This identification results in control signals for a logic network which computes the amount of the refund and controls the printing of a refund slip by an associated printer.
SUMMARY OF THE INVENTION
The present invention relates to apparatus for receiving individual empty beverage containers and cartons of empty beverage containers on a conveyor and handling the containers for refund purposes. An oscillating alignment arm urges the individual containers and the cartons into single file progression for passage through an illuminating station. A switch arrangement recognizes cartons for conditioning identification means. An arrangement of photocells within the illumination station transmit other signals to the identification means as a result of which properly filled cartons are distinguished from improperly filled cartons. At the same time the return value of all empty containers is determined. A paddle mechanism moves the cartons off the conveyor to a separating station. The paddle mechanism includes a series of paddles swung in ferris wheel fashion upon a pair of chains. An arm and track arrangement provide the necessary support for maintaining the paddles firmly against the cartons. At the separating station a roller arrangement transports properly filled cartons in one direction for storage. Improperly filled cartons are transported in another direction for return to the customer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic drawing of the mechanism of this invention.
FIG. 2 is a plan view of container handling mechanism in accordance with this invention.
FIG. 3 is a schmatic illustration of container movement during recognition by a row of photocells and associated circuitry.
FIGS. 4A and 4B is a schematic drawing of registration circuitry.
FIGS. 5A and 5B is a schematic drawing of carton latch circuitry.
FIGS. 6A and 6B are a schematic drawing of money select circuitry.
FIGS. 7A and 7B are a schematic drawing of calculation circuitry.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A conveyor arrangement 10 in accordance with this invention may be constructed as schematically illustrated in FIG. 1. The arrangement includes a conveyor belt 11, with associated driving elements, aligning mechanism as indicated generally at 15 and a paddle arrangement as indicated generally at 12. The cooperating operation of conveyor belt 11, paddle arrangement 12, and aligning mechanism 15 can best be understood by reference to FIG. 2.
Movement of belt 11 is initiated by pushing a start button on a control panel (not illustrated). A customer who wishes to obtain a refund for empty beverage containers pushes the start button and thereafter loads individual empty containers 23 and cartons of empty containers 24 upon belt 11. Loading is performed at a receiving station, which is separated from the major portions of conveyor 10 by a wall 25.
After being loaded upon belt 11, individual containers 23 and cartons 24 are met by a friction surface 26 on arm 27 of aligning mechanism 15. A ratchet arrangement causes arm 27 to oscillate back and forth as illustrated generally by the arrow 28, and this urges the containers and cartons sidewardly against sideboard 14. Sideboard 14 has a friction surface, which retards forward movement of the containers and cartons. The containers and cartons are trapped against sideboard 14 and behind arm 27 until released by outward movement of the arm. A blade 29 is pivotally attached to arm 27 and is urged against the cartons and containers by a spring mechanism 30. This produces separation between the cartons and containers in the direction of belt movement.
After movement past aligning mechanism 15, the containers and cartons pass a series of microswitches (not illustrated), which are positioned so as to be actuated only by cartons. Thereafter the containers and cartons pass into an illumination region between an illuminating apparatus 16 and a series of photosensors 18. Illuminating apparatus 16 generates a series of illuminating beams 17, which are directed angularly with respect to the direction transverse to the direction of conveyor movement. The angle between the beam direction and the transverse direction is preferably in the order of about 18 degrees, so that the identification circuits can recognize pairs of containers within a carton. Each beam 17 is directed toward an individual photocell 31 (FIG. 3), and the beams are preferably beams of collimated infrared light produced by TIL 31 infrared light sources and collimating lenses. Preferably each beam 17 has a diameter in the order of about one-quarter inch.
After passage through the illuminating station the containers and cartons pass under paddle arrangement 12. Paddle arrangement 12 includes a series of paddles 13, which may be actuated to move in the direction indicated by the arrow 21. Paddle arrangement 12 is actuated whenever a carton 24 is positioned thereunder. As mentioned previously, the system is conditioned by a series of switches to discriminate between cartons and individual containers. Thus paddle arrangement 12 is never actuated during passage of an individual container thereunder, so that individual containers are carried along to a bottle storage area.
When paddle arrangement 12 is actuated, a paddle 13 is brought into contact with the side of a carton, and the carton is pushed transversely onto a separating station 19. Paddles 13 swing freely in ferris wheel fashion on chains 51, but during the lower quadrant of their movement, they are held rigidly downward by arms 52 which include a roller 53 for bearing against a track 54. This enables the paddles to push sidewardly against cartons.
Separating station 19 comprises a series of rollers 20, which are driven either forwardly or reversely by a drive motor 22. If the system recognizes the carton as being properly loaded, then drive motor 22 drives rollers forwardly, and the carton is accepted. If the carton is improperly loaded with bottles of different size or has empty cells, then motor 22 drives rollers 22 reversely, and the carton is rejected.
The technique for identifying a container for refund purposes can be understood by reference to FIG. 3. As the belt 33 carries a container 23 in front of photosensor array 18, the light falling upon the vertically arranged row of photocells 31 is periodically blocked. Each photocell 31 has an output line 32, which transmits an electrical signal corresponding to light and dark conditions at the photocell. By way of example, the illustrated photocell 31a may be the first photocell to sense the presence of the container 23. This causes a transition in the output signal from line 32a as indicated at 33. A second photocell 31b has a light to dark transition somewhat later in time, followed at a still later time by a dark to light transition, both transitions being indicated by the output signal on line 32b. The latter transition on the output signal from line 32b is indicated by the reference numeral 34. Lines 32 are connected through a series of gates to different ones of a plurality of registration circuits. For processing the container illustrated in FIG. 3, one such registration circuit is connected to lines 32a and 32b and is configured in such a manner as to generate a registration pulse if the transition 34 occurs after time t 1 and before time t 2 . The time period between time t 1 and t 2 is established by counting a series of clock pulses 35 generated by an encoder 36 arranged for viewing an optical disc 37 mounted on the drive motor 38. Output pulses from encoder 36 are carried by line 39.
It will be seen that clock pulses 35 occur in synchronism with the actual physical movement of container 23. In a typical case such an encoding arrangement may generate a new clock pulse 35 each time container 23 moves a distance of 0.01 inches. Thus by counting the clock pulses 35 the registration circuitry responds to beverage containers having a particular horizontal dimension within some predetermined dimensional range. For instance, a particular registration circuit may be configured for recognizing bottles having an illustrated dimension X equal to 2.5 inches. A bottle meeting this criterion would cause the transition 34 to occur on line 32b at a point in time determined by counting 250 of the clock pulses 35. In order to allow for some error a registration "window" of perhaps 20 clock pulses might be employed. This would cause generation of a registration signal for bottles having a dimension X ranging between 2.4 inches and 2.6 inches. It is apparent that a system constructed in accordance with this invention could be made to recognize a great many different registration conditions.
Electrical circuitry for controlling the apparatus of FIGS. 1 and 2 and generating container value signals is illustrated in FIGS. 4A, 4B, 5A, 5B, 6A, 6B, 7A, and 7B. In addition to the illustrated circuitry the apparatus utilizes fairly conventional power supplies, display controls, transmission lines, clock signal generators, photosensor drivers, and amplifiers. Table I lists circuit types for integrated circuits illustrated in the detailed electrical schmatics presented herein.
TABLE I______________________________________Reference Numeral Circuit Type______________________________________401 4013402 14557403 14557404 4013405 14557406 14557407 14557408 14557409 4013410 4013411 4013412 4013413 14528415 14528501 4076502 4076503 4013504 4013505 14040506 4013507 4013601 4008602 4008603 4008604 4076605 4076606 4076607 4029608 4029609 4029701 4013702 4013703 4013704 4013705 4013706 4013707 4013708 4013709 4013710 4013711 4013712 4013713 4029714 4013______________________________________
FIGS. 4A and 4B illustrate the registration circuiry, which generates the above mentioned registration pulses. The circuitry of FIGS. 4A and 4B generates a registration signal for a container having a particular dimension within some predetermined range or for different containers having the specified dimension within that range. Typically empty containers can be grouped in groups having some common dimensional characteristic within a relatively small dimensional range and a commn refund value. The circuitry of FIGS. 4A and 4B would generate a registration signal for all such containers, and this registration signal would appear at output terminals 6 and 7 of integrated circuit 413. Containers having a different common dimensional characteristic are identified by registration circuitry similar to the circuitry of FIGS. 4A and 4B but programmed in a different manner as hereinafter described. Additional registration circuits are provided for recognizing pairs of containers positioned within cartons. For such pairs of containers the recognition count begins at the leading edge of one container and terminates at the trailing edge of the other container. This type of recognition or registration is performed by observing those portions of the container pairs which extend upwardly above the sides of the carton.
Conveyor clock pulses 35 are received at terminal J of the registration circuitry and are applied to the clock terminals of counters 402 and 403. Counting of such clock pulses is enabled by a signal at terminal B, and this signal may be the transition 33 appearing on line 32a as described above with reference to FIG. 3. The signal level at terminal C also controls conveyor clock counting. Terminal C is connected to that one of photocells 31 which is located at a height immediately over the top of the container. The photocell which is connected to terminal C must be illuminated to order for counting to be enabled.
It will be seen that counter 402 is connected to a counter 405 in serial fashion, so that an output appears at terminal 10 of counter 405 after a predetermined number of conveyor clock pulses have been counted. This count, which takes place during a time period t 1 as illustrated in FIG. 3, is controlled by presetting the counting control terminals of counters 402 and 405.
When the present count is reached, flip-flop 409 is set, and counter 407 is enabled to begin counting conveyor clock pulses. Counter 407 is set to count a predetermined number of conveyor clock pulses corresponding to the desired registration window. Flip-flop 409 is reset when this predetermined count has been reached.
While clock 407 is counting, input terminal 5 of flip-flop 411 is HI, so that the flip-flop is conditioned to respond to a signal transition, such as the transition 34, appearing on input terminal H. If the signal transition occurs at terminal H during the registration window, then flip-flop 411 is triggered to produce an output for application to gate portion 416 of integrated circuit 413. Integrated circuit 413 produces registration output signals on its N and P terminals.
Six terminals 421 through 426 are provided for added counting flexibility. For a simple registration, as above described, a jumper is attached between terminals 421 and 423, and another jumper is attached between terminals 425 and 426. Different jumper connections may be made in order to enable registration on the basis of photocell transitions appearing at both of terminals D and H. In the case where photocell transitions appearing at terminal D are to be recognized, counters 403, 406 and 408 are utilized. These counters work in a manner similar to counters 402, 405, and 407 for controlling flip-flops 410 and 412. If it is desired to condition the registration signal output upon occurrence of appropriately timed signal transitions at both of terminals D and H., then a jumper is placed between terminals 422 and 423 and another jumper is placed between terminals 425 and 426. A sequential count registration condition can be made by placing a jumper between terminals 421 and 423 and another jumper between terminals 424 and 426.
When registration signals are generated by the registration circuitry, they are applied to input terminals for money select circuitry as illustrated in FIGS. 6A and 6B. Connections to this circuitry in general depend upon the types of containers expected. For instance, in a market area wherein there are only 10 cent bottles and 20 cent bottles to be received, the money select circuitry may be connected to receive registration inputs only from terminals M-1 through M-4 as illustrated. Terminal M-1 might be connected to receive registration signals from registration circuitry which recognizes individual 10 cent bottles, while terminal M-2 might be connected to receive registration signals only from circuitry which recognizes pairs of 10 cent bottles arranged side by side in cartons. Similarly, input terminals M-3 and M-4 may receive registration signals for individual 20 cent bottles and 20 cent bottle pairs respectively.
If 10 cent bottles are returned in a six bottle carton, three registration signals will appear at terminal M-2, and three 20 cent counts will be made by the system. If a single 10 cent bottle is registered, then a single 20 cent count is made. The calculation circuitry of FIGS. 7A and 7B perform a division by 2 in order to reduce such a single 20 cent count to a 10 cent output. 20 cent bottles are handled in a similar manner.
For the above example money counts are added by integrated circuits 602 and 605 and later counted down serially through a counting chain comprising counters 607, 608 and 609. For the described arrangement integrated circuits 601, 603, 604 and 606 are not utilized. Counting of the stored money value is initiated by a signal at line 611, which is generated by the calculation circuitry of FIGS. 7A and 7B and appears as an output at line 715 thereof. The money select circuitry counts 100 KHz clock pulses appearing at line 610, and when the countdown is completed a DONE signal appears at line 612.
FIGS. 5A and 5B illustrate the carton latch circuitry, which conditions other circuitry for recognizing and handling carton registration information. Carton recognition information is provided by three microswitches located on the conveyor and by the lower most of photocells 31. The three microswitches are illustrated schemtically on FIG. 5A as switches 508, 509 and 510. The input signal from the lowermost photocell is received by the carton latch circuitry on line 512. During a condition when the lower most photocell is darkened and switches 508 through 510 are closed, an output from gate 511 sets flip-flop 504. At the same time gate 515 is activated to permit later shutdown of the system.
When flip-flop 504 is set, the reset output at pin 12 enables counter 505 to begin counting conveyor clock pulses 35 received on line 513. The output count from counter 505 is applied to a small bottle gate 516 and a large bottle gate 517. When the output count from counter 505 indicates a distance equal to the maximum dimension of a pair of small bottles, then gate 516 enables another gate 518. If at that time gate 518 is also sensing a small bottle output signal from pin 2 of flip-flop 506, then flip-flop 507 is set to provide failure signals on lines 519 and 520. Similarly gate 517 creates large bottle failure signals through gate 521 and flip-flop 507. This enables the circuitry of FIGS. 5A and 5B to provide a failure signal on lines 519 and 520 if a carton is detected and one of the carton cells is empty.
Registration signals for bottle pairs are transmitted from the registration circuits to the carton latch circuiry on lines 522 through 528. Registration circuits for large bottle pairs are connected to lines 522 through 524, while registration circuits for small bottle pairs are connected to lines 525 through 528. Signals on lines 522 through 528 control the setting of flip-flop 506 through gate 529. Each time the carton latch circuitry receives a registration signal for a bottle pair (or a single bottle in special type cartons) an output pulse is provided on line 530, provided, however, that no failure signal has previusly been generated. Whenever conditions are met for generating a carton failure signal, a signal is also generated on line 531 for inhibiting latches 501 and 502 and preventing transmission of registration signals by line 530.
The carton latch circuitry also utilizes a carton registration delay signal, which it receives on line 532 and a master clear signal, which it receives on line 514.
When a carton failure signal appears on line 519, it is transmitted to the calculation circuitry of FIGS. 7A and 7B for reception on line 716. The failure signal on line 520 is transmitted to other circuitry which controls the operation of reversing motor 22.
The calculation circuitry of FIGS. 7A and 7B generally controls other circuitry, not illustrated, which operate displays, printers, coin changers, or the like. The output signal for controlling such peripheral equipment appears as a series of pulses on line 717. Line 717 transmits one pulse for each cent to be printed, indicated or displayed. The calculation circuitry is able to generate the correct number of pulses by counting master clock pulses (100 KHz) on line 718. The counting is carried out synchronously with the money count in the money select circuitry. As stated previously the money select count is initiated by a signal on line 715 of the calculation circuitry and terminates when counters 607 through 609 have been counted down. The DONE signal, which appears on line 612 to signify end of count, is transmitted to the calculation circuitry for reception by line 719.
The calculation circuitry receives other input signals on lines 720 through 724. The signal on line 720 is a delayed registration signal. Whenever the system senses an individual empty container and generates a registration signal at the output of one of the registration circuits, the registration signal is also applied to delay circuitry, not illustrated. After a suitable delay in the order of about 5 microseconds, the registration signal is applied to line 720.
Line 721 receives a carton recognition signal from line 533 of the carton latch circuit. This carton recognition signal prevents double registration when a carton is present.
Line 722 is connected to receive carton registration pulses from line 530 of the carton latch circuit. As stated previously, these pulses represent carton bottle pairs.
Line 723 receives a master clear LO signal from status circuitry, not illustrated. The signal on line 723 goes LO 250 milliseconds after power is applied to the system.
Line 724 receives delayed carton registration signals from delay circuitry, not ilustrated. This signal is required for processing carton having a single row of tandem bottles. The bottle count for single containers is doubled in the bottle select circuitry. The signal on line 724 informs the calculation circuitry that the multiplication need not be performed, even though a carton is present. The multiplication operation is performed through interconnection between flip-flop 712 and counter 713.
Output line 725 carries a bottle count. Line 725 transmits one pulse for each empty beverage container which is recognized by the system. If the containers are carried by a carton, line 725 transmits one pulse for each container in the carton.
Output lines 726 and 727 are connected to the money select circuitry of FIG. 6. Line 726 supplies the clock signal, which is received by the money select circuitry on line 610. Line 727 provides a latch reset signal, which is received by the money select circuitry on ine 613. Lines 728 through 731 are optional calculation output lines for use in computing sales tax.
The money count division, which has been referred to above, is carried out by flip-flop 709. This division provides a true return value for individual empty containers.
While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention. | An apparatus for receiving and handling empty beverage containers. The empty containers may be received either individually or in cartons upon a moving conveyor. An alignment mechanism separates the containers and moves them to one side of the conveyor. A switch arrangement senses cartons, so that the system can process cartons of empty containers in a different manner than individual empty containers. The containers, whether individually or in cartons, pass through an illumination station wherein they interrupt illumination falling upon a row of photocells. Output signals from the photocells are transmitted to identification circuitry together with clock signals generated in synchronism with the movement of the conveyor. The identification circuitry generates registration signals, which are used to compute value of the containers being received. A paddle mechanism shifts the cartons to a separating station, which forwards properly filled cartons to a storage area. Improperly filled cartons are returned to a point near the receiving area. | 8 |
FIELD OF THE INVENTION
The present invention relates to a shock-absorbing transport and storage wrapping made from two webs of flexible material, preferably of plastics or plastic laminates, having gas or air filled spaces between said webs.
BACKGROUND AND OBJECTS OF THE INVENTION
Refrigerators and freezers, washing machines and similar prismatic articles are frequently damaged during transport from the manufacturer to the user. Even if the goods is well wrapped, shocks or collisions against other objects may tear or deform the wrapping.
One object of the present invention is to provide a shock-absorbing wrapper which may be applied along corner-portions of the article. This gives a protection not only to the corner as such but the side surface between two corner wrapper strings will be maintained at a certain distance from other objects.
One additional object of the invention is to provide a technique which offers an optimum of transport and storage protection for products wrapped in a wrapping having preformed cavities of individually variable size and shape.
Another object of the invention is to provide an efficient wrapper manufacturing method.
STATE OF THE ART
From the packaging technique within the electronics industry there are known webs having formed therein small (in the size of 10 to 20 mm) spheres filled by air and spaced in a close sphere to sphere-pattern. Such wrappers do provide shock-absorption in combination with an outer protective package, generally a cardboard box. Sheets of said wrappers are simply placed along the planar innersides of the box.
Another known technique makes use of elongated, blown up, air filled, proximate cylindric spaces between the pair of flexible webs. Such technique does also provide a restricted pattern configuration for the protective elements of the wrapping. The configuration may be described as a "nodistance" cylinder to cylinder configuration. The cylinders are so close to each other that the web loses its folding characteristics.
SUMMARY OF THE INVENTION
A shock absorbing wrapper according to the present invention is characterized by two flexible webs, at least one of which is thermoformable, permanently formed and joined such that at least two rows of gas-filled cushions of arbitrary size and shape are formed, the width of the web being such that at least two rows of cushions are separated a distance allowing the rows to be folded relative each other.
A method for manufacturing of a shock-absorbing wrapper of the type comprising two weldable flexible webs is characterized in that series of gas-filled cushions of arbitrary shape and dimension are formed in one of said webs by a thermoforming process in a thermoforming machinery, and that the two webs are moved past stations for length-wise and cross-wise welding, and in that the width of the webs are such and the welding station placed such that at least two rows of cushions are formed, separated by a distance sufficient for allowing the rows of pillows to be folded against each other.
In order to safeguard the protective funtion of the cushions, a gas, preferably air, is blown in between the webs just before the welds of each individual, thermoformed recess are finished.
One article, for instance a freezer, is transferred from a wrapping station on a wooden pallet and is protected by a cardboard wrapper and/or wooden frames. A shock-absorbing wrapper according to the present invention is applied at least along the vertical corner-portions. Thereafter a shrink film is applied around the object, and after being heated the shrink film fixes the freezer, pallet and any wooden frames plus the shock-absorbing corner wrappers.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 schematically shows a freezer being wrapped by corner-protection means according to the present invention,
FIG. 2 shows a portion of a wrapper band according to the present invention,
FIG. 3 shows a section through the band, but with the longitudinal portions of the band folded 90° relative each other,
FIG. 4 very schematically shows the method of manufacturing the wrapping band,
FIG. 5 is a cross-section taken from FIG. 4,
FIG. 6 is a plan view showing the side of the band having specific cushions according to a second embodiment,
FIG. 7 is a section along line VII--VII in FIG. 6, and
FIG. 8 is a broken section along line VIII--VIII.
DESCRIPTION OF PREFERRED EMBODIMENTS
In FIG. 1 the reference numeral 10 denotes an arbitrary, prismatic article, for instance a freezer, which should be wrapped and transported, standing on a pallet 11. In the traditional manner the freezer may be wrapped by corrugated cardboard.
In order to protect the freezer efficiently during the transport, bands of pressurized, thermoformed cushions are attached along the vertical corner-portions of the freezer. Possibly, similar bands may be attached along the upper horizontal corner-portions.
As appears best from FIG. 2, each band 12 comprises two rows 13 of pillows 14 having four-sided planar shape. The rows of cushions are seperated by a solid strip 15 which is wide enough for allowing folding of the band such that the rows of cushions will be placed 90° relative each other, as shown in FIG. 3.
The bands 12 may be glued to the corrugated cardboard wrapper. In that case where this wrapper is enforced by wooden frames, the band may be stitched to such applications which is best carried out by a robot.
Finally, the entire unit is enclosed within shrinkable plastics which after heating tightens the seperate elements to a unit and forms a reinforced transport protection.
The manufacture of the band is carried out as schematically shown in FIG. 4, where basically a thermoforming machinery is shown operating from a pair of rollers carrying webs of thermoformable material.
Two webs 16, 17 of plastic foil, preferably a LD-polyethylene, are unrolled from rollers 18, 19 and transported generally in a horizontal direction past stations for thermoforming recesses forming bladders after being sealed by the other web. The recesses have a formstable shape also when the bladders are unpressurized. In one embodiment the bladders are given a four-sided planar shape and arranged such that they cover a substantial portion of the surface of the band, only surrounded by the necessary weld seams.
In order to give the cushions a sufficient depth and predetermined lateral dimensions for the intended shock-absorption function, the bladders are permanently thermoformed with a minimum of mechanical memory from at least one of the webs.
At 20 there is shown a station for forming recesses 21 by thermoforming, i.e. a certain portion of the material of the strip is heated and sucked and/or pressed into a mold.
The two bands 16, 17 are thereafter brought to pass a sealing station 22 for longitudinal welding of the webs 16, 17.
In a manner known per se the station 22 may comprise the traditional heat sealing equipment or heated wheels 23 for welding webs along the outer longitudinal edges, as well as between the recesses or bladders 21 so that there is obtained an elongated strip for folding of the webs.
Gas, preferably air, is blown in between the bands 16, 17 from a source for pressurized air 24 immediately before the welding station 22, such that the recesses covered by the other web are safely pressurized by gas before they are sealed to cushions 14 which takes place in the welding station 25 where heated jaws operate in the cross-wise direction between the bladders 21.
The band manufactured in the described manner may be rolled up or folded in a storage, from which it may be taken out as desired, but of course the machinery may operate also intermittently and produce bands as desired and feed such out from the machinery in desired predetermined lengths.
The two rows of gasfilled, pressurized cushions in the embodiment according to FIGS. 1-5 having a square/rectangular basic shape offer an excellent protection for corner-portions as well as surfaces therebetween. Possibly, both webs may be provided with bladders, and the attachement to the object to be transported may be carried out in different manners. The lower web 17 having no bladders may for instance be provided with a layer of glue covered by a removable protective film.
In FIG. 8 there is shown a tool to be used in a conventional thermoforming machine for forming "bladders" or recesses of basically two different types (or alternatively FIG. 8 may be said to represent a cut piece of a sealed two web wrapper having been thermoformed in said tool).
The section in FIG. 7 shows two different types for the bladders 26, 27 and a certain region 28 therebetween where the two webs are sealed.
The reference numerals 29, 30 represent folding denotations for facilating the folding of the piece of band, generally to any required angle between 0-90° around a horizontal axis.
FIG. 8 shows the hight 30 and length 31 of the cushions in the vertical direction in said fig.
The possibility of providing permanently deformed, possibly gas-filled and pressurized, cushions or bladders improves drastically the protecting ability of the wrapping. Even if one or several bladders are punctured, such bladders maintain a shock-absorbing capacity also after being depressurized because the punctured bladder acts as a shock-absorber from which gas has to be pumped out through the punctured areas. Basically, the thermoforming procedure does also allow a 100% tailored piece of cushion band for a specific shock-absorbing purpose, meaning that the wrapping will act at an optimum irrespective of the shape of the article on which it is fastened. | A customized shock-absorbing wrapper band comprising at least two rows of gas-filled cushions of arbitrary shape and size formed by joining two flexible webs, at least one of which is thermoformable, and pressurizing the thermoformed recesses when sealing such by the other web in a sealing station of a thermoforming, roller operated machine. | 8 |
BACKGROUND OF THE DISCLOSURE
While most wells are drilled more or less vertically, it is not uncommon to deviate a well so that it is drilled at an angle from the vertical. A typical situation arises with an offshore platform where many wells are brought to the surface at the platform. It is not uncommon to find as many as thirty wells at a single platform. While several of the wells might deviate only a few degrees from the vertical, a large number of such wells will deviate outwardly from the platform to place a number of wells into a productive formation. Of the thirty wells, perhaps as many as twenty will be substantially deviated from the vertical. They will typically radiate in all directions of the compass on viewing the platform from above. The angle of deviation in a given well will vary significantly. Deviation angles in the range of zero to about 45 degrees still permit the use of wireline supported equipment in the drilling of the well, and various and sundry completion techniques. When a well is highly deviated, typically in the range of about 45 to about 75 degrees, it is more appropriate to describe the well as being horizontal than vertical, at least in the deviated portion. Such high angles of deviation from the vertical create more or less horizontal portions in the well, and there are difficulties in getting wireline tools through such highly deviated portions.
Wireline supported tools, whether supported on a slick line or on a multi-conductor armored logging cable, including a support wire and various conductors, all operate successfully by traversing the well borehole by gravity. Gravity fall and wireline retrieval is thus a routine matter in getting wireline supported tools into and out of the well borehole. In a highly deviated well, the wireline supported tools do not travel so readily.
In a highly deviated hole, wireline tools may snag or hang on the rough surface that defines the drilled hole. In open hole, the surface can vary over a wide range of roughness. Even when it is smoothed by a mud cake there still is a high risk of snagging the gravity moved wireline tool. Even if the hole has been cased, there is still an element of risk of snagging the tool at threaded connections between joints.
One approach to overcoming the possibility of snagging in highly deviated holes is to run the logging tool into the well on a string of drill pipe. This is described as being "drill pipe conveyed". An assembly is connected to the lower end of a string of drill pipe and is forced into the deviated hole to position the logging apparatus at a specified depth in the hole. When this is done, positioning can be achieved in a reliable fashion, but it is then difficult to get the signals created by the logging apparatus out of the well. For instance, logging apparatus supported by a string of drill pipe may form a multitude of signals transmitted from the logging apparatus up through the drill string. Heretofore, signals have been delivered by means of various conductors in an armored logging cable. While the drill pipe is made of metal and can serve as a pipe conductor, in practice, quality of the conductor is so poor that an electrical connection must be made with a high quality conductor wire, one pair or more, to thereby provide a signal path. Moreover, some logging tools utilize electrical power and thus, a quality connection must be made from the surface to the logging tool (on the drill string) whereby electric current flows from the surface to the logging apparatus. The required quality of connection mandates the use of a logging cable including at least a pair of conductors to deliver electric current from the surface to the logging apparatus, and also, the incorporation of suitable conductor paths to deliver signals from the logging apparatus back to the surface. This can be done with a pair of conductors, if nothing else through the use of multiplexing to obtain the equivalent of more than a single conductor pair.
With this background in mind, the present disclosure is directed to a system whereby a logging tool in the form of an assembly affixed to a string of drill pipe is first installed at a suitable depth in the well. Thereafter, an overshot is dropped into the string of drill pipe. If it tends to stall, it can be pumped down by the use of a drilling fluid such as drilling mud. This will force it to the bottom. At that point, the overshot makes mechanical and electrical connection to the logging assembly for the purpose of providing the quality electrical connection required for operation. The present apparatus enables a connection to be made, disclosing a pumpdown overshot cooperative with a wet connector. Moreover, it enables mechanical connection utilizing a type of self-cleaning boot with a bayonet connector featuring a J-slot which enables a positive mechanical connection to be made. it is not sensitive to dynamic pressure which may vary widely depending upon circumstances of the deviated well. Connection is achieved wherein the mechanical load is handled separately, in a manner of speaking, so that separate and proper electrical connection is achieved. The overshot latches to the wet connector assembly at the bottom of the string of drill pipe, thereby assuring proper operation of the system. By proper manipulation of wireline tension, connection can be made and then connection can be ended enabling retrieval of the wireline and the overshot affixed to it.
While the foregoing sets forth the problem and mentions briefly certain features of the present apparatus, the detailed description set forth below will more clearly describe the construction of the apparatus and its mode of operation.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings.
It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIGS. 1A-1C show a drill pipe conveyed logging assembly which is adapted to be positioned in a highly deviated hole to locate the logging assembly at a required depth;
FIGS. 2A and 2B are a detailed sectional view through the wet connector assembly which is connected above the logging assembly and which faces upwardly enabling subsequent electrical connection necessary for operation of the logging tools; and
FIGS. 3A-3C are a detailed sectional view along the length of the overshot incorporating a specially designed stinger which connects with the wet connector of FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The drill pipe conveyed logging assembly of FIG. 1 will be described first. Then, the wet connector which is affixed to the lower end of the drill pipe will be described in detail. After that, the overshot assembly shown in FIG. 3 will then be described, at which time, a sequence of operation of the equipment will then be set forth.
In FIG. 1 of the drawings, the numeral 10 identifies a drill string. A single joint of drill pipe is indicated at 11 and it is threaded to a centralizer housing adapter 12 by means of a conventional, typical threaded connection 13. At the last threaded connection or perhaps bottom-most two or three threaded connections, an interval sleeve 14 is incorporated which guides or centralizes the overshot. The centralizers 14 centralize and direct the overshot so that it will make certain contact with the logging assembly as will be described. the drill pipe joints can be of conventional construction andlength, typically 30 feet being normal. The centralizer members 14 are spaced closer together and thus short subs are used at 17 and 18 to space the centralizers 14. They are located to assure proper alignment and connection of the overshot to the wet connection. The sub 18 thus threads to a cooperative sub 19 which in turn threads to a sleeve 20. The sleeve 20 threads to a transition piece 21 which has a larger OD, and the passage onthe interior becomes larger. It is larger to enclose a housing 22 which encloses a suitable logging tool. The precise nature of the logging tool is not given. Various and sundry logging tools can be used with this equipment and are placed in the housing 22. To this end, the transition piece 21 may be constructed of special metals. For instance, metals which do not interfere with magnetic fields may be used. A wide variety of logging tools can be incorporated in the housing 22 and the particular nature of the logging tool is not specified.
The logging tool is located in the housing 22. That housing connects to what is termed a closure head 23 at the top end of the housing 22. In turn, that supports the wet connector of the present disclosure identified generally by the numeral 25. The wet connector is centralized and held in location by a suitable adjusting nut 24. The nut 24 is captured between connected segments of the enlarged housing 21. The exterior of the wet connector is threaded so that the threaded connection can be readily achieved. The threaded nut 24 thus supports the wet connector 25 and also aligns it centrally of the drill pipe. Details of construction of the wet connector 25 will be set forth on describing FIG. 2. It is sufficient to note that it incorporates an upstanding central member which extends upwardly toward the centralizers 14 for mechanical connection. Moreover, it provides an electrical connection from the logging tools in the housing at 22.
In operation, the apparatus shown in FIG. 1 is installed in a deviated hole by assembling the string of drill pipe joint by joint. The drill pipe is measured in length. This enables control over the location of the logging tools, thereby assuring that the logging tools are positioned at a required depth in the deviated hole. For instance, suitable pipe can be added to locate the logging tools at a specified depth of 10,000 feet. Here, the term depth refers to length along the deviated hole, and it does not necessarily refer to depth into the earth. When the drilled well is true to vertical, the two measurements are the same, but in this instance, the highly deviated well requires measurement along the length of the well to the necessary location where the logging tools are used.
The wet connector shown in FIG. 1 is enlarged in FIG. 2. The description of the wet connector will proceed from the bottom to show how it connects with the logging assembly therebelow. To this end, the numeral 26 identifies signal conductors connected with an insulated conductor post 27 which connects to an insulated pair of conductors through the equipment. The threaded housing 28 has a fluid seal in the seal rings 29. The threads 30 enable the wet connector assembly 25 to thread to the closure head 23 previously described. This locates the threads 31 for connection with the nut 24. The wet connector incorporates an insulated spacer 32 on the interior which aligns the conductor 27. The conductor 27 thus passes through the insulated spacer 32, and is also held in position by similar insulating spacer 33. The conductor is on the interior of an elongate central rod 34. The rod 34 extends upwardly to the very tip of a central plug 35.
The threaded body 28 is closed at the top end by an externally threaded member 36 locked in position by means of a lock screw 37. It includes an upstanding skirt 38 surrounded by an upwardly facing shoulder 39. The skirt 38 supports a J-slot sleeve 40. The sleeve 40 is constructed with a J-slot 41 which enables locking with a cooperative pin. A hollow sleeve 42 defines the upstanding support, the sleeve 42 supporting a surrounding guard sleeve 43. The sleeve 43 telescopes or slides away. The sleeve 43 is also used to centralize the overshot more closely. It slides downwardly against the force of a coil spring 44. Downward travel of the sleeve 43 is limited by the lower shoulder 45 on the sleeve. This downward stroke is sufficient in length to expose the connector plug 35. The connector plug 35 is normally sheltered by the surrounding guard sleeve 43. The connector plug 35 functions as a male connector. The J-slot 41 is used to assure mechanical connection. The sleeve 40 supporting the J-slot is rotatable, being caught between two shoulders and permitted to rotate. On rotation, alignment is achieved with an overshot 50 for that purpose. An important factor is the fact that the male plug 35 makes electrical contact to be made for proper operation.
Attention is now directed to the overshot 50 shown in FIG. 3. Construction of this device will be set forth proceeding from the top end. At the very top, there is a sleeve 51 which encloses a connective fitting 52. This fitting 52 is used to complete connection to the electrical conductors in an armored logging cable (not shown). The logging cable is terminated at the electrical connector 52 and also incorporates a threaded sleeve (not shown) which threads on the interior of the sleeve 51 to thereby make mechanical connection to the overshot shown in FIG. 3. The electrical connector 52 is sealed by a set of O-rings at 53 and it is supported on a plug 54, the plug 54 supporting the upstanding sleeve 51, previously mentioned. The plug 54 threads to a fixed external sleeve 55 which encloses suitable seals and threaded connectors which surround the internal conducting wire enclosed within an armored jacket 56.
The body supports a resilient external sleeve 57 which has a number of centralizing rings or ribs 58. Moreover, they function as a fluid seal. In ordinary use, the overshot 50 is dropped in drill pipe. It will travel as far as possible along the drill pipe. It may stall as a result of the highly deviated well. The overshot is forced along the remaining length of the drill pipe string by pumping drilling fluid behind the overshot. The resilient rings are large enough so that a pressure differential is created which faces or pumps the overshot through the drill pipe. An open annulus is present between the drill pipe I.D. and the resilient ring O.D. to allow drilling fluid to flow around so that the overshot can be recovered at a faster speed when required. Enough force is created to pump down the overshot while still allowing fluid to by-pass the resilient rings and circulate through the drill pipe. The overshot is then forced to the bottom of the well by means of the hydraulic drive behind the resilient members on the exterior of the overshot body.
Forward of the resilient sleeve, the overshot is constructed to include an external protruding rod-like member which includes a number of sinker bars at 59. The sinker bars surround the armored conductor jacket 56 on the interior. One or more sinkers are included, depending on the weight required to cause the apparatus to travel to the very extreme end of the string of drill pipe. Suitable seals and spacers are incorporated for construction of the apparatus forward of the resilient member 57 and which will be termed the stinger. The stinger is indicated generally by the numeral 60 and refers to that portion which is forward or below the resilient member 57 just described.
The stinger incorporates a threaded member 61 which threads to a hollow sleeve 62. The sleeve is perforated with openings at 63 to enable pressure equalization between the exterior and the interior of the sleeve. The armored conductor jacket 56 extends downwardly to the electrical fitting 64 on the interior. The fitting 64 is held by a series of insulated washers and a nut at the top end of the fixed electrical connector fitting 64. The fitting 64 supports a flexible multiconductor conduit 65 extending from the lower end and spaced from the walls of the surrounding sleeve 62. The sleeve 62 threads to a continuation sleeve which functions as an alignment cylinder 66. Internal pressure is equalized by providing the drilled hole 67 in it. The sleeve 62 terminates at an interior shoulder providing a seat for a coil spring 69. The coil spring 70 is compressed against the shoulder of sleeve 62. The spring 69 cooperates with an overshot piston 70, the piston 70 having an upstanding axial sleeve 71 which fits loosely around the conduit 65. There is sufficient gap to enable the wire to bend or flex. While the sleeve 71 rises in the tool, there is sufficient clearance to avoid pinching the wire 65.
The piston 70 is shown in the downward stroke or position. The conduit 65 connects at its lower extremity to a boot 71 which encloses the conductors connecting with a set of connector rings on the interior of a female socket 72. The piston 70 clamps to the boot 71 so they move together. The boot 71 and the socket are normally made as a single unit and move as a unit. The socket 72 is axially aligned and will ultimately connect with the male plug 35 on the wet connector 25 shown in FIG. 2. Thus, the tip of the plug 35 stabs into the socket 72 thereby completing the connection. In the downward stroke, travel of the socket is limited by the shoulder at 73. This shoulder axially limits movement of the socket 72 to prevent piston and boot from falling out of overshot because of spring force. The socket 72 can move upwardly, this movement being accompanied by upward movement of the piston 70 and compression of the spring 69. This movable portion of the equipment is urged downwardly normally by the spring 69, but the spring force can be overcome. The upper end of the sleeve 71 extends around and is loosely spaced from the wire 65 to avoid pinching. Upward travel to the maximum permitted does not pinch any surplus or extra length of the conduit 65 which coils loosely in the extra space permitted for coiling.
The sleeve 66 is provided with a pressure equalizing opening at 74. Therebelow, the sleeve 66 threads to a sleeve 75 for ease of assembly and disassembly and to also define the interior should 73. The bottom sleeve 75 is an extender sleeve having the same external diameter as the sleeve 66. The sleeve 75 has a downwardly facing internal shoulder 76. The shoulder 76 has an axial opening to enable the plug 35 to extend upwardly past the shoulder. However, the shoulder 76 is sized to align the guard sleeve 43 previously mentioned. The guard sleeve 43 will be driven down to expose the plug 35 because it will rub against inner sleeve and then will extend upward due to force of the spring 44. The guard sleeve assists in closer, more accurate alignment for mating the plug and socket.
In addition, opposing pins 77 are included to engage the J-slots 41. They provide a solid mechanical connection, it being observed that the pins 77 connect to the sleeve 75 which in turn is structurally solid from there to the top end of the overshot 50. Thus, this solid construction enables tension to be taken on the overshot body.
In operation, the string of drill pipe at 10 is placed in the well to locate the logging apparatus at the required depth. Once this has been accomplished, the overshot 50 is dropped into the drill string. If it falls fully to the bottom and achieves connection, that is well and good. It if stalls, drilling fluid can then be pumped down the string of drill pipe. In any case, the overshot is forced to the bottom by gravity free-fall, use of weighted bars 59, and pumping down. When it comes to the vicinity of the wet connector 25 shown in FIG. 2, the following occurs. The stringer 60 is first of all centralized through the centralizing cups 14 on the interior of the string of drill pipe. Once centralized, the stringer is aligned with the wet connector. Upon centralization, it stabs into the wet connector 25. This movement helps to perfect a mechanical connection as well as an electrical connection.
The sleeve 75 passes over the upper end of the wet connector assembly. Simultaneously, the inwardly protruding pins 77 (preferable a pair to cooperate with a pair of J-slots) enter into the topmost gap in the J-slots. They travel along the respective J-slots, and are able to force the sleeve 40 supporting the J-slots to rotate when the pins 77 bottom out. In FIG. 2 of the drawings, the dotted line position at 80 shows the bottom extremity of the movement of the pin 77 in the J-slot mechanism. A pull is taken on the wireline from the surface and if proper J-slot engagement has occurred, the pin 77 moves from the dotted line position at 80 to the upper dotted line position at 81. This assures the operator at the surface that a proper mechanical connection has been made. As long as the equipment has this connection, the overshot cannot be pulled free. If desired or conditions render it necessary, the wireline may be pulled free of the cable head by pulling a predetermined load with a calculated weal point at the cablehead. On slacking off, the pin moves from the dotted line position at 81 back towards to the dotted line position at 80. This, then, permits the pin to move out of J-slot to achieve complete disengagement. Thus, a down/up/down/up movement sequence is required to engage and disengage. This permits the equipment to be mechanically connected with a high degree of certainty and then to achieve disconnection with equal certainty.
While the foregoing describes the mechanical connection that is accomplished, the electrical connection should be noted also. The male plug 35 makes proper connection with the socket 72. Relative upward movement to connect is permitted. The overshot piston 70 is able to move upwardly. The range of travel permitted by the piston 70 overcomes or is greater than the range of travel required to accomplish J-slot latching. Thus, while the pin 77 move through the various positions in the J-slot to accomplish locking, the piston 70 is able to ride upwardly or downwardly to assure connection between the plug 35 and the socket 72. Maximum travel of the overshot is limited by the upward facing shoulder 39 of the housing 36. In other words, overrunning is not permitted. While this linear travel is accomplished between the overshot and the wet connector, on the interior of the overshot, the socket 72 rides upwardly and downwardly to make contact with the plug 35. The spring 69 bears against the plug and socket connection to assure that the connection is held continuously.
After a signal is received through the electrical conductors, the connection has been made, and the signal can be monitored to assure that the connection is continued. This electrical connection through the plug and socket operates without regard to the load on the pins 77 and the cooperative J-slots. This is a means of assuring connection even when drilling fluids may be in the vicinity. Even so, the plug and socket are able to make connection, both in dry environment or wet with drilling fluid. Their connection is made electrically sound and safe by the application of the spring force through the spring 69. Yet, they are not a load bearing connection. They are simply stabbed together and pulled apart, in the ordinary operation of the overshot, provided the J-slot connector mechanism handles the mechanical load. This shifts the load away from the electrical connectors.
While the foregoing is directed to the preferred embodiment, the scope thereof is determined by the claims which follow. | For use in drill pipe conveyed logging systems wherein the logging apparatus is enclosed in a housing affixed to the lower end of a drill pipe string, a system is disclosed utilizing a wet connector and overshot. The wet connector includes a centralized upstanding mechanical connector means having a J-slot cooperative with pins inserted thereinto. The J-slot is adjacent to a sleeve which telescopes over an enclosed and protected upwardly facing electrical connector means. On the overshot, the solid body thereof includes a lower appended skirt having inwardly protruding pins which engage the J-slots to achieve a separate mechanical connection. There is internally of the overshot a spring mounted telescoping and movable electrical connector including a cooperative socket engaging the plug of the wet connector. The electrical connection is kept separate from the mechanical connection so that the entire load of operation is carried separately without interfering with operation of the electrical connectors. | 4 |
FIELD OF THE INVENTION
The present invention relates to a process for producing humanspecific gamma-interferon (abbreviated as "HuIFN-gamma" hereinafter) using human whole blood and to a method for assaying the HuIFN-gamma productivity of human blood.
DESCRIPTION OF THE PRIOR ART
In recent years, clinical tests whereby the level of serum enzyme or its metabolite is determined chemically have been in wide use.
Since HuIFN-gamma, a blood component, exhibits antiviral- and antitumor-activities, it has been suggested to include the measurement of serum HuIFN-gamma level in clinical test. Such suggestion, however, has not been realized because serum HuIFN-gamma exists in minute amounts.
Blood comprises a fluid, plasma, in which formed elements such as erythrocyte, leukocyte and platelet are suspended. One mm 3 of blood from an adult generally contains, in addition to 7.4×10 3 leukocytes and 3×10 5 platelets, 5.4×10 6 erythrocytes in man or 4.8×10 6 in woman.
It is well known that HuIFN-gamma is produced by human leukocyte.
In conventional processes to produce HuIFN-gamma, viable leukocytes separated from human blood are used. As is evident from, for example, Y.K. Yip et al., Infection and Immunity, Vol. 34, pp. 131-139 (1981), and T. Kasahara et al., The Journal of Immunology, Vol. 130, No. 4, pp. 1784-1789 (1983), leukocytes are separated from other elements present in whole blood, and then allowed to secrete HuIFN-gamma.
Detailed studies on these conventional processes confirmed that these processes, however, give a low recovery yield of leukocytes from blood, i.e. 30-50%, of the leukocytes are damaged during the separation to lower the viability to 40-60%, and, eventually, lower the overrall recovery yield to approximately 10-30%, as well as that the separated leukocytes give an inconsistent HuIFN-gamma production. These render the determination of blood HuIFN-gamma productivity very difficult, and cause one obstacle in mass-production of HuIFN-gamma.
DETAILED DESCRIPTION OF THE INVENTION
As the results of researches for the mass-production of HuIFN-gamma using precious human blood, as well as for the assay of blood HuIFN-gamma productivity using donated blood, the present inventor found that a large amount of HuIFN-gamma can be easily produced by incubating whole blood in a vessel while exposing the whole blood to an anticoagulant and a gamma-interferon inducer (IFN-gamma inducer). The present inventor also found that blood HuIFN-gamma productivity can be determined with ease and high reproducibility by incubating whole blood in a vessel while exposing the whole blood to an anticoagulant and an IFN-gamma inducer, and titrating the accumulated HuIFN-gamma.
Detailed studies confirmed that the exposure to an IFN-gamma inducer in an amount of 10-10,000 micrograms/ml whole blood is favorable.
The wording of "whole blood" means fresh blood preparations collected from donors, and also suspensions which are obtained by removing the plasma liquid from fresh blood preparations and suspending the residual formed elements in a suitable non-plasma liquid, e.g. saline, buffer solution or nutrient culture medium.
The anticoagulants usable in the invention are those which prevent the coagulation of whole blood, and which do not affect HuIFN-gamma production thereof. Examples of such anticoagulants are heparin, acid citrate-dextrose (ACD), and citrate-phosphate-dextrose (CPD).
The IFN-gamma inducer usable in the invention are those which induce HuIFN-gamma production in whole blood. Examples of such IFN-gamma inducers are mitogens such as phytohaemagglutinin; concanavalin A; pokeweed mitogen; staphylococcal enterotoxin (SEA); lipopolysaccharide; endotoxin; polysaccharide including β-glucan and arabinogalactan; and bacteria including those of genera Pseudomonas and Corynebacterium.
Specifically, we found that phytohaemagglutinin induces a high HuIFN-gamma titer generally within a relatively brief time of 10-30 hours.
The appropriate range for IFN-gamma inducer inoculum is 10-10,000 micrograms/ml whole blood.
One or more alpha-interferon inducers (HuIFN-alpha inducers), such as virus and nucleic acid, can be used together with HuIFN-gamma inducer to enhance HuIFN-gamma production and/or to induce simultaneous HuIFN-alpha production.
The step of incubating whole blood in a vessel in the presence of anticoagulant and IFN-gamma inducer is carried out in such a manner that the whole blood contacts with the anticoagulant and IFN-gamma inducer in the vessel to secrete HuIFN-gamma. For example, to the prescribed amounts of anticoagulant and IFN-gamma inducer in a vessel is added an appropriate amount of whole blood, and the mixture is incubated in the vessel. Alternatively, a mixture of anticoagulant and whole blood is placed in a vessel, added with an IFN-gamma inducer, and incubated in the vessel. In this incubation step, a suitable medium, e.g. saline, isotonic buffer or nutrient culture medium, may be added.
Tank, jar, flask, test tube, ampul and micro plate well of any shape and capacity can be used as the vessel.
The incubation conditions are those under which HuIFN-gamma is producible: for example, temperature range of 30°-40° C.; and 10-90 hours of incubation. Priming and/or superinduction can be carried out during HuIFN-gamma production, if necessary.
The whole blood which has been incubated to produce HuIFN-gamma is then optionally diluted with saline or isotonic buffer, and separated with suitable procedure(s), such as centriguation or filtration, to remove the formed elements such as blood cells. Thereafter, the resultant supernatant or filtrate containing HuIFN-gamma is subjected to purification or HuIFN-gamma titration.
The HuIFN-gamma can be easily purified by combination of conventional procedures, e.g. salting-out, dialysis, filtration, concentration, adsorption and desorption by ion exchange, gel filtration, affinity chromatography using a suitable ligand such as antibody, isoelectric point fractionation and electrophoresis, to obtain a high-purity HuIFN-gamma.
The HuIFN-gamma thus obtained is advantageously usable in injection or drug for external or internal use in the prevention and treatment of human diseases. It may be used alone or in combination with one or more substances, e.g. antiviral agent, immunoactivator, antioncotic, etc.
Any assay method is employable in the invention as long as the HuIFN-gamma produced by whole blood is titrated thereby. Specifically suited are the bioassay, radioimmunoassay and enzyme-linked immunosorbent assay.
In recent years, the enzyme-linked immunosorbent assay has been developed as a highly safe, convenient and speedy assay. Any enzymelinked immunosorbent assay is employable as long as HuIFN-gamma is titrated as the antigen thereby. Examples of such enzyme-linked immunosorbent assays are the double antibody sandwich technique and modified double antibody sandwich technique.
It was confirmed that the HuIFN-gamma productivity determined in this way is useful for testing the individual donor clinically.
The method according to the invention confirmed that the blood collected from a cancer patient is much lower in HuIFN-gamma productivity than those collected from healthy donors.
The following experiments further explain the present invention.
EXPERIMENT 1
Effect of pretreatment on blood HuIFN-gamma productivity
The effect of pretreatment on blood HuIFN-gamma productivity was studied. In this Experiment, fresh blood specimens collected from three healthy donors were used after heparinization.
The treated bloods used in this Experiment were as follows: a plasma-free suspension, obtained by centrifuging blood to remove the plasma liquid and suspending the residual formed elements in RPMI 1640 medium to give the same element density as that in blood; and an ammonium chloride-treated suspension, obtained by treating blood with Tris-HC1 buffer (pH 7.2) containing 0.75% ammonium chloride in usual way to effect the haemolysis of the erythrocytes, centrifuging the mixture and suspending the resultant erythrocyte-free formed elements in RPMI 1640 medium to give the same element density as that in blood.
One ml aliquots of either heparinized or treated blood were placed in plastic test tubes which were then added with 0.1 ml aliquots of saline containing phytohaemagglutinin-P in respective amount of 0, 50 or 500 micrograms, followed by 24-hour incubation at 37° C. The supernatants obtained by centrifuging the incubated mixtures were assayed for HuIFN-gamma titers per ml whole blood.
The HuIFN-gamma titers were determined with the use of "GAMMA INTERFERON IRMA KIT", a radioimmunoassay kit for HuIFN-gamma, commercialized by Celltech, Ltd., Berkshire, England.
The results are given in Table 1.
These evidences clearly confirm that whole blood and plasmafree suspension containing the whole formed elements of blood are suitable for specimen for determining blood HuIFN-gamma productivity because they give a high and consistent HuIFN-gamma titer. Also was confirmed that the ammonium chloride-treated suspension wherein the erythrocytes were haemolyzed and removed gives a low and inconsistent HuIFN-gamma titer.
TABLE 1______________________________________ Phytohaemagglutinin Healthy donorTreatment (microgram) A B C______________________________________No treatment 0 0 0 0 50 230 200 280 500 540 600 620Plasma-free 0 0 10 0suspension 50 220 230 240 500 570 640 670Ammonium chloride- 0 0 10 0treated suspension 50 0 30 20 500 0 40 10______________________________________
EXPERIMENT 2
Effect of IFN-gamma inducer inoculum on blood HuIFN-gamma productivity
The effect of IFN-gamma inducer inoculum on blood HuIFN-gamma productivity was studied. Fresh blood specimens collected from three healthy donors and two cancer patients, i.e. liver cancer patient and stomach cancer patient, were used after heparinization.
According to the method in Experiment 1, one ml aliquots of either heparinized blood specimen were placed in test tubes, added with 0.1 ml aliquots of saline containing phytohaemagglutinin-P as the IFN-gamma inducer in respective amount of 0, 1, 10, 10, 1,000 or 10,000 micrograms, incubated and assayed for HuIFN-gamma titers per ml blood.
A series of experiments using 100,000 micrograms of phytohaemagglutinin-) per ml blood was planed, but omitted because dissolution of such amount of phytohaemagglutinin was unsuccessful.
The results are given in Table 2.
TABLE 2______________________________________Phytohaemagglutinin Healthy donor Cancer patient(microgram) D E F G H______________________________________0 0 0 0 0 01 0 0 0 0 010 130 100 120 0 0100 410 380 430 0 101,000 680 620 760 0 2010,000 670 660 710 0 20100,000 ND ND ND ND ND______________________________________ Note: ND means not done; patient G, liver carcinoma patient; and patient H, stomach cancer patient.
These evidences clearly confirmed that IFN-gamma inducer inocula of 10-10,000 micrograms/ml blood are favorable.
Also was confirmed that the blood collected from a cancer patient is much lower in HuIFN-gamma productivity than those collected from healthy donors. After determining the HuIFN-gamma productivites of whole blood specimens collected from twenty healthy donors and twenty cancer patients using 100 micrograms of IFN-gamma inducer per ml whole blood, it was found that the HuIFN-gamma productivity of healthy donor was 420±100 units/ml blood, while that of cancer patient was 10±10 units/ml blood. This suggests that the assay of donated blood on its HuIFN-gamma productivity would be helpful for the detection of cancer in its early stage.
Several embodiments of the present invention will be disclosed.
EXAMPLE A
Assay of blood HuIFN-gamma productivity
Example A-1
One ml heparinized specimen of a fresh blood from a 28 years old healthy man was placed in a plastic test tube, added with 250 micrograms of phytohaemagglutinin-P, and incubated at 37° C., for 24 hours. The supernatant obtained by centrifuging the incubated mixture was assayed for HuIFN-gamma titer with the radioimmunoassay kit similarly as in Experiment 1.
The HuIFN-gamma productivity was about 420 units/ml blood.
EXAMPLE A-2
One ml heparinized specimen of a fresh blood from a 33 year old healthy woman was added with 500 micrograms of concanavalin A, and incubated at 37° C. for 64 hours. The incubated mixture was then assayed for HuIFN-gamma titer similarly as in Example A-1.
The HuIFN-gamma productivity was about 380 units/ml blood.
EXAMPLE A-3
A heparinized specimen of a fresh blood from a 61 years old healthy man was centrifuged to remove the plasma. The formed elements so obtained were then centrifugally washed in saline, and suspended in RPMI 1640 medium to give the same element density as that in blood.
One ml of the resultant suspension was placed in a plastic test tube, added with 300 micrograms of pokeweed mitogen, and incubated at 37° C. for 48 hours. Thereafter, the HuIFN-gamma titer of the resultant specimen was assayed with the double antibody sandwich technique, an enzyme-linked immunosorbent assay.
The HuIFN-gamma productivity was about 200 units/ml blood. The value determined with the enzyme-linked immunosorbent assay was in good consistency with the radioimmunoassay value.
EXAMPLE A-4
A heparinized specimen of a fresh blood from a 58 years old male lung cancer patient was treated similarly as in Example A-1 to obtain an HuIFN-gamma productivity of about 20 units/ml blood.
EXAMPLE A-5
A heparinized specimen of a fresh blood from a 55 years old female hysterocarcinoma patient was treated similarly as in Example A-1 to obtain an HuIFN-gamma productivity of about 10 units/ml blood.
EXAMPLE B
Production of HuIFN-gamma
EXAMPLE B-1
One ml heparinized specimen of a fresh blood from a healthy volunteer was placed in a plastic test tube, added with 250 micrograms of phytohaemagglutinin-P, and incubated at 37° C. for 24 hours. The supernatant obtained by centrifuging the incubated mixture was assayed for HuIFN-gamma titer.
The HuIFN-gamma production was about 420 units/ml blood.
EXAMPLE B-2
One ml heparinized specimen of a fresh blood from a healthy donor was added with 500 micrograms of concanavalin A, incubated at 37° C. for 64 hours, and assayed for HuIFN-gamma titer. The HuIFN-gamma production was about 380 units/ml blood.
EXAMPLE B-3
A heparinized specimen of a fresh blood from healthy donors was centrifuged to remove the blood plasma, and the residual formed elements were centrifugally washed in saline. The formed elements were then suspended in RPMI 1640 medium to give the same element density in blood.
The suspension was then placed in a mini jar, added with poke-weed mitogen in an amount of 200 micrograms/ml suspension, incubated at 37° C. for 64 hours, and assayed for HuIFN-gamma titer similarly as in Example B-1.
The HuIFN-gamma production was about 240 units/ml blood.
EXAMPLE B-4
A suspension of blood formed elements was prepared similarly as in Example B-3.
The suspension was placed in a mini jar, added with phytohaemagglutinin-P in an amount of 500 micrograms/ml suspension, incubated at 37° C. for 28 hours, and assayed for HuIFN-gamma titer similarly as in Example B-1.
The HuIFN-gamma production was about 600 units/ml blood.
It will be obvious to those skilled in the art that various changes and alterations may be made without departing from the scope of the invention and the invention is not to be considered limited to what is described in the specification. | Production of HuIFN-gamma and assay of blood HuIFN-gamma productivity both using donated blood are disclosed. Human whole blood secrets a high titer of HuIFN-gamma when exposed to an IFN-gamma inducer (e.g. mitogen) in the presence of anticoagulant (e.g. heparin, ACD, and CPD). Blood HuIFN-gamma productivity is determined by titrating the secreted HuIFN-gamma with a suitable procedure (e.g. bioassay, radio-immunoassay, or enzyme-linked immunosorbent assay). The blood of cancer patient is lower in HuIFN-gamma productivity than that of healthy donor. The HuIFN-gamma per se is recovered and purified prior to its prophylactic and therapeutic uses. | 8 |
The present invention relates to small-scale or micro-sized fabrication techniques of a type employed for integrated circuit manufacture, for example, and more particularly to use pulsed laser energy in such applications.
BACKGROUND OF THE INVENTION
It has heretofore been generally proposed to employ laser-initiated explosive energies in fabrication of integrated circuits. In Cranston U.S. Pat. No. 3,727,296, for example, small charges of explosive material, such as azide or fulminate explosives, are deposited on the free ends of integrated circuit leads which are cantilevered over a substrate. The explosive material is ignited by laser energy to propel the lead ends against the underlying substrate with sufficient force to bond the leads to the substrate. In order to detonate explosive materials, a minimum quantity of explosive is necessary. This minimum quantity is determined at least in part by the so-called deflagration to detonation distance, which is the distance required for an ignition shock front to propagate to explosive detonation. Thus, the technique proposed in Cranston is both difficult to control on the scale therein disclosed, and is not amenable to use on a smaller scale, such as in fabrication of the integrated circuits themselves. There is also a problem of explosion by-products.
Frish et al, "Surface Coating and Alloying by Laser Induced Heat and Pressure," Final Report, NSF Grant No. DMR-8260087 (May 1983) and "Metal Bonding with High Intensity Laser Pulses," SPIE Proceedings, Vol. 458 (Jan. 1984) propose bonding metal foils to substrates of dissimilar metal by placing the foil in contact with the substrate and then irradiating the foil surface remote from the substrate with a laser pulse so as to ablate a portion of the foil surface. Thermal and pressure waves are generated in the foil and travel through the foil thickness at differing velocities. If the thermal wave reaches the foil/substrate interface during irradiation, both materials will melt and thereafter mix under the influence of the laser-induced pressure gradients. Thus, the disclosed "laser stamping" technique makes use of both heat and pressure supplied to the foil by the high intensity laser pulse.
Drew et al T988007 (1979) discloses a laser vapor deposition technique wherein a CW laser beam is directed through a transparent substrate onto a reservoir of metal on the opposite side of and spaced from the substrate. The laser beam heats and vaporizes the metal of the reservoir, which is then redeposited on the opposing surface of the substrate.
Mayer et al, "Plasma Production by Laser-Driver Explosively Heated Thin Metal Films," J. App. Phys., 57, February 1985, pp 827-829, discloses a technique for producing metal vapor clouds or plasmas for studying laser/plasma interactions. A thin metal film on the surface of a glass substrate is irradiated by a short laser pulse directed through the substrate. The laser energy is absorbed by classical skin-depth absorption to rapidly heat and "explode" the film from the substrate preferentially along an axis perpendicular to the substrate surface. A high-power second laser beam is thereafter directed into the resulting metal vapor plasma to heat the plasma and thereby provide opportunity for controlled study of laser/plasma interactions.
OBJECTS AND SUMMARY OF THE INVENTION
It is a general object of the present invention to provide improved microfabrication techniques having utility in manufacture of integrated circuits and like applications.
A further object of the invention is to provide improved techniques of the described character which employ conventional pulsed laser technology.
Another and yet more specific object of the invention is to provide a method for depositing, bonding and/or forming materials on a substrate employing pulsed laser microexplosions, and a system for performing such a method.
In accordance with the preferred embodiments of the invention herein disclosed, a first substrate of transparent material, such as glass, has one or more target materials positioned on a surface, preferably a flat surface, of the substrate. These target materials include a thin film of electrically conductive material--i.e., a conductor or semiconductor--immediately adjacent to the substrate surface. Pulsed laser energy is directed through the transparent substrate onto the conductive film at a sufficient intensity and for a sufficient duration to rapidly vaporize the metal film. The target materials are propelled by film vaporization energy and by the reaction thereof against the glass substrate onto the opposing or object surface of a second substrate. In various embodiments of the invention herein disclosed, the object surface of the second substrate is either spaced from the target materials on the first substrate, whereby film vaporization energy explosively propels the target materials across the intervening gap or space. Alternatively, the first substrate, target material and second substrate are in sandwiched contact, whereby the vaporized film is restrained from explosion, and the target materials are bonded to the object surface of the second substrate by interaction of temperature and pressure at the object surface.
In one embodiment of the invention, the exploding vapor is deposited as a coating or layer onto the spaced opposing surface of the second substrate, thereby providing an improved laser vapor deposition technique. Due to site selectivity of the laser vaporization, coupled with the uniform geometry of the exploding vapor cloud, this laser vapor deposition technique may be employed for controlled deposition of conductive films of complex and intricate geometries. In a second embodiment of the invention, a flyer section of material carried by the conductive film is propelled intact by film vaporization energy across the intervening gap against the opposing surface of the second substrate. When sufficient energy is imparted to the flyer section, the latter is bonded by impact to the opposing surface of the second substrate. In one application of this embodiment, ohmic contacts are selectively bonded to GaAs semiconductor substrates. A lesser amount of vaporization energy causes the flyer section to conform to the surface contour of the second substrate without bonding thereto, thereby providing a process for forming of micro-sized articles of desired contour.
GENERAL DESCRIPTION OF THE DRAWINGS
The invention, together with additional objects, features and advantages thereof, will be best understood from the following description, the appended claims and the accompanying drawings in which:
FIG. 1 is a schematic diagram of a first embodiment of the invention;
FIG. 2 is a schematic diagram of an application of the laser vapor deposition process illustrated in FIG. 1;
FIGS. 3A-3D are schematic illustrations of a second embodiment of the invention at successive stages of operation;
FIG. 4 is a schematic diagram of an application of the laser bonding process illustrated in FIGS. 3A-3D;
FIG. 5 is an exploded schematic diagram of a second application of the process of FIGS. 3A-3D;
FIG. 6 is a schematic diagram of a third embodiment of the invention for impact-forming of micro-sized articles;
FIGS. 7-8 are graphic illustrations useful in discussing operation of the embodiment of FIGS. 3A-3D; and
FIG. 9 is a schematic diagram of yet another embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 illustrates a first embodiment of the invention as including a laser target 20 comprised of a flat transparent substrate 22 having a thin film 24 of electrically conductive material deposited on one surface thereof. Energy from a pulsed laser 26 coupled to a suitable laser control 29 is focused through substrate 22 onto film 24 on a axis 28 which is substantially normal to the film/substrate interface 30. That portion of film 24 which is illuminated by laser 26 is rapidly heated and vaporized by the laser energy deposited therein. The resulting vapor cloud 32 "explodes" preferentially along axis 28 on a uniform substantially cylindrical vapor front (assuming a circular laser beam) across a gap 34 onto the target surface 36 of an opposing substrate 38, where the exploded film plasma is vapordeposited as at 40.
As noted above, film 24 is of electrically conductive material, including both conductors and semiconductors having carrier concentrations in excess of about 10 17 cm -3 . Aluminum, gold and nickel are examples of suitable metallic conductors, and impurity-doped silicon and germanium are examples of suitable semiconductors. The thickness of film 24 is coordinated with the intensity and duration of the pulsed output of laser 26 focused thereon to obtain rapid and complete vaporization of the film material. More specifically, thickness of film 24 is chosen to be approximately equal to the thermal diffusion depth L expressed by Equation (7) (see Equation Appendix), where k is the thermal conductivity of the film material, C v is the specific heat per unit mass, rho-1 is the density of the film material and t p is the laser pulse duration. In general, pressure at vaporization increases with intensity and film thickness. Laser energy is deposited by classical skin/depth absorption, and foil thickness should be at least equal to skin depth for a given laser energy and foil material to obtain desired efficiency. Pulse duration should be no more than is needed to obtain complete vaporization at desired intensity and film thickness.
By way of example only, target 20 may comprise a glass substrate 22 having a thickness of 1 mm. Film 24 of aluminum may be deposited on substrate 22 by any suitable vapor deposition or other technique and possess a thickness in the range of 10 2 to 10 4 A. Laser intensities of 10 9 to 10 12 W/cm 2 at a pulse duration of between 10 -10 and 10 -8 sec would heat the illuminated section of film 24 to a temperature of between 2000° and 100,000° K. The resulting pressure at interface 30 would be up to the order of a few hundred kilobars. Gap 34 may range in length between zero (direct contact between film 24 and target surface 36) and a few millimeters. In general, using a substrate 22 of glass construction, laser 26 has a wavelength (nominal) in the visible or near-infrared regions of the spectrum. Long-wavelength pulsed lasers may also be employed, provided of course that substrate 22 is of a construction that transmits energy at the wavelength chosen.
FIG. 2 illustrates an application of the laser-explosive vapor deposition technique of FIG. 1 for selective pattern deposition onto substrate 38. A mask 39 having the desired deposition pattern 41 stencilled therein is positioned to intersect the laser beam, allowing only a portion of the laser energy corresponding to pattern 41 to be focused onto target 20. Because of the inherent site selectivity of the vaporization process, coupled with the uniformity in the expanding vapor front 32 (FIG. 1) noted in practice of the invention, the resulting pattern 40 on substrate 38 conforms quite closely to pattern 41 in mask 39.
FIGS. 3A-3D schematically illustrate a second embodiment or application of the invention for bonding a workpiece section of material onto surface 36 of substrate 38. The target 20a of FIG. 3A includes a workpiece section or "flyer" 42 deposited or otherwise disposed on film 24. The periphery of flyer 42 corresponds to the focused periphery of the laser beam at film 24, e.g. circular, so that the portion of film 24, and only that portion of film 24, sandwiched between flyer 42 and substrate 22 is vaporized. Pulsed laser energy at intensity E L and duration t p (FIG. 3B) is focused through substrate 22 onto film 24 and vaporizes the film as previously described. The exploding force of the vaporized film propels flyer 42 across gap 34 at velocity V p (FIG. 3C) against substrate surface 36 (FIG. 3D) with sufficient force than an impact bond is formed at the interface.
For explosive bonding to occur, it is necessary that flyer velocity V p be between predetermined limits which vary with flyer and substrate materials. Table I (see Appendix) indicates minimum and maximum velocities V p for bonding to occur between a flyer 42 and substrate 38 of exemplary identical metals. Assuming that all energy of the vaporized film is transferred to flyer 42, the kinetic energy E k of the flyer may be expressed by Equation (1), where epsilon is efficiency of laser energy transfer to flyer 42, rho-2 is density of the flyer material, d is thickness of flyer 42 and D is flyer diameter (FIG. 3B). Equation (1) can be rearranged as shown in Equation (2). The intensity I of incoming laser energy can be expressed as shown in Equation (3), where it is assumed that the diameter of focused laser energy at film 24 is equal to the diameter D of flyer 42. Vapor pressure P at film 24 is given by Equation (4), where c is a coupling coefficient. In tests, laser intensities on the order of 10 11 W/cm 2 having a pulse duration t p of 10 -10 sec were sufficient to vaporize films of Al having a thickness of 1000 A to produce a pressure P of 200 kbar. The constant epsilon was observed to be about 0.1, and the constant c was taken to be about 2.0 dyne/W.
Substituting Eq (3) into Eq (4) yields Equation (5). Substituting Eq (2) into Eq (5) yields Equation (6). For a given combination of materials for flyer 42 and substrate 38, rho-2, V p -max and V p -min are fixed. For a particular laser, c and epsilon are constants. Thus, pressure P, thickness d and pulse duration t p can be determined per Eq (6). For given thickness d, a variety of laser energies E L and diameters D are available, as shown by Eq (1).
FIG. 7 is a graph which illustrates laser intensity I as a function of flyer thickness d required to give velocity V p -max (Table I) for Al, Ag and Cu. The constant epsilon is taken as 0.1, and the pulse duration t p is 10 -10 sec. (Lesser values of epsilon move the curves to right.) The vertical lines represent differing values of c. Bonding will occur for the different combinations of I and d for each material plot which lie to the right of the intersections with the appropriate value of c. FIG. 8 is a graph which illustrates laser energy E L versus diameter D for differing thicknesses d of a flyer 42 of silver composition at c equal to 2.0 dyne/W, epsilon equal to 0.1 and t p equal to 100 psec. The foregoing discussion assumes that film 24 is normal to axis 28 (FIG. 1). For other angles, the area of the focused laser energy is increased, and intensity is correspondingly decreased, as trigonometric functions of angle.
FIG. 4 illustrates an important application of the laser explosive bonding technique of FIGS. 3A-3D. A known problem in the fabrication of gallium-arsenide semiconductors lies in deposition of ohmic contacts. Contact conductors deposited by vapor deposition or other typical conventional techniques do not exhibit good adhesion to the semiconductor substrate, and also may exhibit high contact resistance. In the illustration of FIG. 4, a flyer 42 is explosion-bonded to form a conductive contact on semiconductor substrate 38 over surface 36 which would typically be an insulating layer. It will be appreciated that the application of FIG. 4 may be employed for repair of a damaged conductive strip 36. FIG. 5 illustrates a further application of the laser explosion bonding technique of the invention. The target 20b in FIG. 5 comprises a glass substrate 22 having the film 24 deposited thereon. Target 20b is effectively divided into three zones or sections 44, 46, 48 having spots or flyers of differing materials, such as Al, Si and C, deposited onto film 24. By jogging target 20b using a suitable control 50, a semiconductor can be manufactured by selective deposition and build-up of Al, Si and C zones on the substrate 38. FIG. 6 illustrates a modification to the embodiment of FIGS. 3A-3D. By employing reduced laser energy, flyer velocity can be reduced so that flyer 42 is formed against, but not bonded to, the contour of substrate 38.
FIG. 9 illustrates a modification to the embodiment of FIGS. 3A-3D wherein the gap or space 34 is reduced to zero. That is, in the embodiment of FIG. 9, target 20a is positioned with workpiece 42 (not a "flyer" in this application) in facing abutment with object surface 36. When film 24 beneath workpieces 42 is vaporized, substrate 22 cooperates with substrates 38 and workpiece 42 to confine the vapor energy. The process of FIG. 9 has been tested with good results in bonding aluminum workpieces 42 to substrates 38 of silicon and copper compositions. Bonding was observed for laser intensities I ranging from 1.0-9.0×10 9 W/cm 2 and duration t p equal to 10 -9 sec. Thickness d was equal to one micron. The bonding process formed films with the best surface morphologies when performed in at least a rough vacuum (25-70 millitorr). This was observed in the Al--Si tests in which large contiguous films were bonded. The Al--Cu tests, not performed in vacuum, showed a clumpier less contiguous film deposition. The surface morphology of the vacuum tests were not as good as control films produced by conventional vapor deposition, which was probably due in major part to large transverse spatial variations in the laser intensity observed in the text. Adhesion testing of the laser-bonding films demonstrated a great increase in adhesive strength over conventional vapor-deposited films.
SEM observation of the film-substrate interface of the Al--Cu targets showed significant intermixing of the two metals. In some cases, a wavy type interface was observed, which is typical of large scale explosive bonding bonds. The intermixing probably accounts for the observed adhesive strength of the laser-bonded films. Optical microscopy of the Al--Si interfaces provided evidence of long contiguous film bonding. SEM observation of the interface was less conclusive. This was in part due to the imaging difficulty in discriminating between the A1 and Si. Also, melting and mixing may have occured, eliminating a discrete interface between the two. In the application of FIG. 9 with workpiece 42 in direct contact with substrate 38, consideration must be given to the role of heat transfer to the bonding process. It is possible that the incident laser pulse induced a temperature profile in which melting temperatures were exceeded to a certain depth, possibly into the substrate. Indeed, empirical calculations indicate that, given the laser parameters and materials involved in these tests, the temperature at the interface between workpiece 42 and substrate 38 exceeded the melting temperatures of both, suggesting that melting and rapid interdiffusion of atoms under pressure may have played a significant role in the bonding process.
TABLE I______________________________________Appendix Density V.sub.p - min V.sub.p - maxMetal (g/cm.sup.3) (m/s) (m/s)______________________________________Al 2.71 182 541Ag 10.49 105 370Cu 8.91 70 187304SS 7.90 271 282______________________________________ | A system and method of pulsed-laser microfabrication wherein a first substrate of transparent material, such as glass, has one or more target materials positioned on a surface, preferably a flat surface, of the substrate. These target materials include a thin film of electrically conductive material--i.e., a conductor or semiconductor--immediately adjacent to the substrate surface. Pulsed laser energy is directed through the transparent substrate onto the conductive film at a sufficient intensity and for a sufficient duration to rapidly vaporize the metal film. The target materials are driven by film vaporization energy and by the reaction thereof against the glass substrate onto the opposing or object surface of a second substrate. | 7 |
BACKGROUND
1. Technical Field
This disclosure generally relates to gas turbine engines.
2. Description of the Related Art
Aircraft engine nacelle inlets are designed to meet many diverse flight conditions such as take-off, crosswind, climb, cruise and windmill. These disparate flight conditions result in competing design considerations often times resulting in a nacelle configuration that is designed for less than optimal performance at cruise conditions. By way of example, the inlet diameter of a typical nacelle typically is 10% to 20% larger than is generally considered optimal at cruise conditions.
SUMMARY
Systems and methods for altering airflow to gas turbine engines are provided. In this regard, an exemplary embodiment of a method comprises selectively increasing an effective diameter of a nacelle inlet while a gas turbine engine mounted within the nacelle is operating.
An exemplary embodiment of a system comprises: a gas turbine engine inlet having a slat, the slat being movable between a retracted position and an extended position; in the extended position, the slat increasing an effective diameter of the inlet compared to the diameter of the inlet when in the retracted position.
Another exemplary embodiment of a system comprises: a slat configured as an annular segment; and a slat actuator operative to move the slat between a retracted position and an extended position.
Other systems, methods, features and/or advantages of this disclosure will be or may become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features and/or advantages be included within this description and be within the scope of the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
FIG. 1 is a schematic diagram depicting an embodiment of a system for altering inlet airflow to a gas turbine engine.
FIG. 2 is a schematic diagram of the embodiment of FIG. 1 , with inlet slats shown in extended positions.
FIG. 3 is a schematic view of another embodiment of a system for altering inlet airflow to a gas turbine engine.
FIG. 4 is a schematic diagram of another embodiment of a system for altering inlet airflow to a gas turbine engine, showing detail of the pneumatic slat actuator and anti-icing components located in the inlet plenum.
DETAILED DESCRIPTION
Systems and methods for altering inlet airflow to gas turbine engines are provided. In this regard, several exemplary embodiments will be described. Specifically, some embodiments involve the use of slats located about the inlet of a nacelle. In some embodiments, the slats are pneumatically actuated by bleed air that also can be used to provide anti-icing for the inlet. The slats can be extended, such as during take-off and landing configurations that typically involve an increased need for inlet airflow. However, the slats can be fully retracted, such as during cruise, thereby reducing drag of the nacelle. Notably, the use of such slats can enable an overall smaller nacelle to be used, e.g., a nacelle that is optimally designed for cruise conditions.
FIG. 1 is a schematic diagram depicting an embodiment of a system for altering inlet airflow to a gas turbine engine. As shown in FIG. 1 , system 100 includes a power plant that incorporates a nacelle 102 and a gas turbine engine 104 . It should be noted that although the gas turbine engine is configured as a turbofan in this embodiment, other types of gas turbine engines can be used.
Nacelle 102 is attached to a pylon 106 that mounts the power plant to a wing of an aircraft (not shown). Nacelle 102 includes an inlet 108 that includes a leading edge 112 . The inlet is configured to direct a flow of air toward an intake of the engine 104 , which includes a fan 110 . Aft of the leading edge on an exterior of the nacelle is an inlet nose cowl 114 . Other portions of the nacelle are not relevant to this discussion and will not be described in greater detail.
The embodiment of FIG. 1 also includes inlet slats, e.g., slat 120 , that are shown in their retracted positions in FIG. 1 . The inlet slats are generally located at the lip of the nacelle and generally conform to the shape of the lip and inlet. Thus, in this embodiment, each slat is configured as a compound annular segment, i.e., each slat is annular along its length as well as in cross-section. In other embodiments, various other shapes can be used.
In FIG. 2 , the inlet slats are shown in their respective extended positions. In the extended positions, the slats generally increase an outer diameter of the inlet, thereby enabling an increase in airflow to the gas turbine engine. In operation, the slats are typically deployed to their extended positions when an increase in airflow is desired, such as during takeoff and/or landing. During cruise conditions, however, the increase in surface area and corresponding profile drag attributable to the extended slats may be undesirable. Therefore, during cruise conditions, for example, the slats typically can be retracted, thereby accommodating an inlet design that is more optimal for cruise conditions.
It should be noted that although the slats in the embodiment of FIGS. 1 and 2 are configured as segments that separate from each other when extended, various other configurations can be used. By way of example, slats that overlap each other even when extended could be used. Additionally or alternatively, various other techniques can be used that alter the thickness of the nacelle lip. Notably, selective altering of the inner diameter and/or outer diameter of the nacelle lip can affect airflow into the engine. In this regard, geometric changes that avoid flow separation are typically preferred.
FIG. 3 schematically depicts another embodiment of a system for altering inlet airflow to a gas turbine engine. As shown in FIG. 3 , system 300 incorporates a gas turbine engine 302 about which a nacelle 304 is positioned. A lip 306 of the nacelle incorporates extendable slats, e.g., slat 310 , that can be moved from retracted positions (shown in FIG. 3 ) to extended positions (shown in FIG. 4 ). It should be noted that the lip of the nacelle defines an interior annular plenum 312 through which bleed air can be routed for providing inlet anti-icing, for example. In this regard, reference is made to the schematic diagram of FIG. 4 , which depicts a portion of plenum 312 and an inlet slat in greater detail. The lip 306 of the nacelle has a generally parabolic shape having a top side 307 that melds into a bottom side 308 at a mid-point 309 forming a leading edge of the lip 306 . The slat 310 has a shape that mimics that parabolic shape of the lip 306 and contacts the bottom side 308 and the top side 307 to mate therewith if in the retracted position.
As shown in FIG. 4 , plenum 312 is defined by spaced inner and outer surfaces 314 , 316 of the nacelle that interconnect at the leading edge 320 . In this embodiment, various components are located within the plenum, including a pneumatic actuator 322 that is operative to alter a position of slat 310 . Specifically, the pneumatic actuator is operative to move the slat between a retracted position (indicated by phantom lines in FIG. 4 ) and an extended position 324 . Notably, in some embodiments, various intermediate positions between the extended and retracted positions can be provided. As shown in FIG. 4 , the slat 310 has an aft inner surface 328 that rests on top of and conforms to a forward surface 329 of the nacelle 304 along the entire length of the slat 310 from end 330 to end 332 thereof in the retracted position (see the phantom lines in FIG. 4 ).
In the embodiment of FIG. 4 , engine bleed air is provided to the pneumatic actuator 322 via a bleed air regulator 326 . The bleed air regulator also provides bleed air to inlet anti-icing components 328 , such as valves and manifolds, which are configured to heat the inlet in order to prevent ice build-up. Notably, the bleed air regulator receives a supply of bleed air and regulates that bleed air for use by the pneumatic actuator and anti-icing components. Clearly, various allocations of bleed air supply among the components that use that supply can be accommodated by the regulator.
It should be emphasized that the above-described embodiments are merely possible examples of implementations set forth for a clear understanding of the principles of this disclosure. Many variations and modifications may be made to the above-described embodiments without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the accompanying claims. | Systems and methods for altering airflow to gas turbine engines are provided. In this regard, a representative system includes a gas turbine engine inlet having a slat, the slat being movable between a retracted position and an extended position. In the extended position, the slat increases an effective diameter of the inlet compared to the diameter of the inlet when in the retracted position. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This applications claims priority from U.S. Provisional Patent Application No. 61/745,952, filed Dec. 26, 2012. The contents of this application are incorporated by reference in its entirety.
BACKGROUND
[0002] Neural modulation of neural tissue in the body by electrical stimulation has become an important type of therapy for chronic disabling conditions, such as chronic pain, problems of movement initiation and control, involuntary movements, dystonia, urinary and fecal incontinence, sexual difficulties, vascular insufficiency, heart arrhythmia, and more. Electrical stimulation of the spinal column and nerve bundles leaving the spinal cord was the first approved neural modulation therapy and has been used commercially since the 1970s. Implanted electrodes are used to pass pulsatile electrical currents of controllable frequency, pulse width, and amplitudes. Two or more electrodes are in contact with neural elements, chiefly axons, and can selectively activate varying diameters of axons, with positive therapeutic benefits. A variety of therapeutic intra-body electrical stimulation techniques are utilized to treat neuropathic conditions that utilize an implanted neural stimulator in the spinal column or surrounding areas, including the dorsal horn, dorsal root ganglia, dorsal roots, dorsal column fibers, and peripheral nerve bundles leaving the dorsal column or brain, such as vagus-, occipital-, trigeminal, hypoglossal-, sacral-, and coccygeal nerves.
SUMMARY OF THE INVENTION
[0003] A wearable device for facilitating neurophysiological treatment of a patient harboring an implanted neural stimulator is provided. The wearable device includes a transmitting antenna configured to accept one or more input signals and to transmit one or more electromagnetic signals to a neural stimulator that is implanted in a patient's body. The wearable device further includes a control circuitry configured to provide the one or more input signals to the transmitting antenna. The wearable device further includes a battery that provides electrical power to at least the control circuitry. The wearable device is configured to be worn outside the patient's body.
[0004] In some embodiments the control circuitry includes a microwave field stimulator.
[0005] In some embodiments, the transmitting antenna is a patch antenna.
[0006] In some embodiments, the wearable device further includes an inductive charging component for transferring electrical energy to the battery.
[0007] In some embodiments, the wearable device further includes a control panel with at least one interface button.
[0008] In some embodiments, a first interface button of the at least one interface button controls at least one neurostimulation setting of the control circuitry.
[0009] In some embodiments, the at least one neurostimulation setting includes at least one of: an amplitude setting, a pulse width setting, a frequency setting, and a preset programs setting.
[0010] In some embodiments, a second interface button of the at least one interface button controls which neurostimulation setting of the at least one nuerostimulation setting is controlled by the first interface button.
[0011] In some embodiments, the wearable device includes a belt member, and the transmitting antenna, control circuitry and battery are mounted on the belt member.
[0012] In some embodiments, the belt member has a length-wise dimension (a circumference) sized to allow the patient to wear the wearable device about a torso portion of the patient's body.
[0013] In some embodiments, the belt member includes at least one flexible portion and at least one rigid portion.
[0014] In some embodiments, the transmitting antenna is mounted on a rigid portion of the belt member and the control circuitry is mounted on a rigid portion of the belt member.
[0015] In some embodiments, the circumference is adjustable by the patient.
[0016] In some embodiments, a portion of the wearable device includes a plurality of layers substantially parallel to a surface of the patient's body, the plurality of layers includes: a ground plane; a conductor layer between the ground plane and the surface of the patient's body; and a dielectric layer between the conductor layer and the surface of the patient's body.
[0017] In some embodiments, the plurality of layers further includes: a first layer of foam between the ground plane and the conductor layer; and a second layer of foam between the conductor layer and the dielectric layer.
[0018] In some embodiments, the transmitting antenna is tuned with the dielectric layer to match a coupling of the surface of the patient's body so that a dielectric fluid is not necessary between the dielectric layer and the surface of the patient's body.
[0019] In some embodiments, the battery is removable from the wearable device to allow for battery replacement.
[0020] In some embodiments, the battery is rechargeable.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1A depicts the wearable antenna assembly placed on the waist of a patient.
[0022] FIG. 1B shows the top view of a wearable antenna assembly on a patient.
[0023] FIG. 2 illustrates a three dimensional view of a wearable antenna assembly.
[0024] FIGS. 3A and 3B show examples of a static length structural belt. FIG. 3A shows the top view of a structural option for a wearable antenna assembly. FIG. 3B shows the profile view a structural option for a wearable antenna assembly.
[0025] FIGS. 4A , 4 B, 4 C show various options for a control panel on a wearable antenna assembly.
[0026] FIG. 5 depicts an example block diagram of the structural layers of a flexible transmitting antenna.
[0027] FIG. 6 illustrates a wearable antenna assembly with a secondary battery dock.
[0028] FIG. 7 illustrates adjustable cabling for circumferential adjustability of the wearable antenna assembly.
[0029] FIG. 8 illustrates adjustable cabling in a flexible wearable antenna assembly to allow for stretch flexibility.
[0030] FIGS. 9A-E demonstrates tensioners used to hold the shape of a flexible transmitting antenna embedded within the wearable antenna assembly to maintain the concave curvature of the individual patient's waist.
[0031] FIG. 9A illustrates a flexible transmitting antenna embedded within the wearable antenna assembly while the pull-string tensioners are not engaged and the antenna is flat.
[0032] FIG. 9B illustrates a flexible transmitting antenna embedded within the wearable antenna assembly while the pull-string tensioners are engaged and the antenna's flexible shape is maintained.
[0033] FIG. 9C illustrates a wearable antenna assembly on a patient where the pull-string tensioners are engaged and the embedded antenna's flexible shape conforms to the lumbar crevice of the patient.
[0034] FIG. 9D illustrates an embedded antenna while the Velcro straps are not engaged and the embedded antenna's flexible shape is not maintained.
[0035] FIG. 9E illustrates an embedded antenna while the Velcro straps are engaged and the embedded antenna's flexible shape is maintained.
[0036] FIG. 10A illustrates a wearable antenna assembly with a two-piece antenna with interlocking fingers that give greater conformity to the lumbar crevice.
[0037] FIG. 10B illustrates a two-piece antenna with interlocking fingers that adjust along the caudal-cranial axis.
[0038] FIG. 11 demonstrates the use of a soft sleeve that is slipped over the structural portions of the wearable antenna assembly.
[0039] FIG. 12 illustrates an embodiment of the wearable antenna assembly with an elastic portion to increase flexibility.
[0040] FIG. 13 illustrates various embodiments of flexible transmitting antenna shapes for the wearable antenna assembly.
[0041] FIG. 14 depicts the use of venting holes in the wearable antenna assembly for evaporation of sweat and increased breathability.
[0042] FIG. 15 is an example of fasteners used to secure the wearable antenna assembly to the patient.
[0043] FIG. 16 illustrates a wearable antenna assembly that is condensed to fit into the shape of a standard watch.
[0044] FIG. 17 illustrates a fabric-antenna made of micro-conducting fibers woven into a structure of fabric to create a flexible antenna.
[0045] FIGS. 18A-B illustrates the flexible transmitting antenna within the wearable antenna assembly. FIG. 18A illustrates the process of depositing materials to create the antenna stack up. FIG. 18B is a block diagram depicting the antenna layers for an assembly where the dielectric, conducting planes, and foam are deposited in to create an ultra thin profile.
[0046] FIG. 19 illustrates a semi-cylindrical array of antennas that are used to transmit power.
[0047] FIG. 20 illustrates a molded flexible transmitting antenna that is snapped into the wearable antenna assembly.
[0048] FIG. 21 is an example of a molded flexible transmitting antenna that conforms to the lumbar crevice, and can be secured directly to tissue using suction cups.
[0049] FIG. 22 illustrates fluid wicking, hydrophilic micro-channels built in to the wearable antenna assembly to displace fluids that would otherwise disrupt the tuning of the antenna.
[0050] FIG. 23 is a block diagram depicting the antenna layers for an implementation where perspiration is used in the tuning calculation of the dielectric within the wearable antenna assembly.
[0051] FIG. 24 demonstrates an antenna array that can be used to select the antenna that is in the best position to power the lead and reduce reflection within the wearable antenna assembly.
[0052] FIG. 25 is an example of a rotary mechanism that allows the antenna to be rotated by 270 degrees within the wearable antenna assembly.
[0053] FIG. 26 demonstrates the use of two flexible transmitting antennas within the wearable antenna assembly to power multiple leads simultaneously with distinct parameters.
[0054] FIG. 27 is an example circuit that can be used to inform the user that RF energy is being transmitted.
[0055] FIG. 28 illustrates the use of signal rails within the belt to allow placement of the battery, control panel, and microwave field stimulator in interchangeable locations along the wearable antenna assembly.
[0056] FIG. 29 is an example of a placement of the microwave field stimulator on the wearable antenna assembly.
[0057] FIG. 30 illustrates the use of differential positioning sensors placed on the wearable antenna to alert the user and adjust stimulation.
[0058] FIGS. 31 and 32 show an example of a belt fastening system with sensor contacts to activate/deactivate the generation of the signal.
[0059] FIG. 33 shows a top view of a wearable antenna assembly according to some embodiments of the present invention.
[0060] FIG. 34 shows a side view of a wearable antenna assembly according to some embodiments of the present invention.
[0061] FIG. 35A shows a top view of a wearable antenna assembly with certain outer portions removed according to some embodiments of the present invention.
[0062] FIG. 35B shows a bottom view of a wearable antenna assembly with certain outer portions removed according to some embodiments of the present invention.
[0063] FIGS. 36A , 36 B, and 36 C show cross section cutaway views of portions of a wearable antenna assembly according to some embodiments of the present invention.
[0064] FIG. 37 shows a longitudinal cutaway view of a wearable antenna assembly according to some embodiments of the present invention.
[0065] FIG. 38 shows an exploded 3 D view of a wearable antenna assembly according to some embodiments of the present invention.
DETAILED DESCRIPTION
[0066] The following detailed description explains various embodiments of the invention. These embodiments are merely illustrative, and those of skill in the art will recognize that other embodiments fall within the scope of the invention.
[0067] FIG. 1A shows an example of a wearable antenna assembly (WAA) on a patient. The wearable antenna assembly includes a soft flexible belt, an adjustable strap, a replaceable battery, an embedded control panel with interface buttons, an embedded microwave field stimulator (MFS), an embedded flexible transmitting antenna, and cabling. In the example, the wearable antenna assembly is secured around the waist of a patient, or an animal. The wearable antenna assembly can be placed around the body at the horizontal vertebrae levels ranging from L5 to T5. The wearable antenna assembly has an adjustable circumferential length from about 22 inches to about 50 inches. Examples of a microwave field stimulator, transmitting antenna, and corresponding implantable neural stimulator with receiving antenna are described in U.S. patent application Ser. No. 13/584,618, title “Microwave Field Stimulator,” which is incorporated herein by reference.
[0068] The microwave field stimulator attached to the wearable antenna assembly is powered by a replaceable battery and controlled by an embedded control panel. The replaceable battery is comprised of rechargeable battery chemistry; such as, but not limited to lithium-ion, lithium polymer, nickel cadmium, nickel metal-hydride, etc. The replaceable battery can have a capacity within a range from 0 mAh to 10,000 mAh. The replaceable battery can have a nominal voltage rating from about 1.0 volt to 20 volts. In certain embodiments, the replaceable battery can be embedded within the wearable antenna assembly and recharged via a wall plug or with wirelessly.
[0069] The microwave field stimulator is connected to the embedded transmitting antenna, which transmits a radio frequency (RF) signal to an implanted receiving antenna within the tissue of the patient, on the skin of the patient, or within an article of clothing close to the body of the patient. The RF signal may have a characteristic frequency within a range from about 800 MHz to about 6 GHz. The embedded transmitting antenna embodied in FIG. 1A is a directional patch antenna, but other antenna types can be used; such as a monopole, dipole, vagi, whip, or horn antenna.
[0070] FIG. 1B illustrates the top view of a wearable antenna assembly on a patient. The embedded control panel, embedded microwave field stimulator, and the embedded transmitting antenna are flexible and can conform to the shape of the patient's back. The microwave field stimulator and the transmitting antenna are low profile and streamlined to contour with the patient's body curves. This low profile allows the patient to conceal the wearable antenna assembly under clothing easily.
[0071] FIG. 2 shows a three dimensional view of a wearable antenna assembly. The adjustable strap can be made of stretchable, supporting material such as elastic or nylon. The adjustable strap can be removed from the wearable antenna assembly to be washed and replaced with an adjustable strap that is either shorter or longer. The width of the adjustable strap can be within a range from about 0.2 inches to about 5.0 inches. The circumferential length of the adjustable strap can be within a range from about 10 inches to about 60 inches. As shown in FIG. 2 , the adjustable strap uses connector tabs that pull through an open slot on the structural wearable antenna assembly and are rotated to lock into place.
[0072] The structural wearable antenna assembly holds the battery, embedded control panel, embedded microwave field stimulator, and the embedded transmitting antenna. The structural wearable antenna assembly can be made of flexible, semi-rigid materials such as elastomers, rubber, neoprene, and polyurethane. The structural wearable antenna assembly can have a width within a range from 0.2 inch to 5.0 inches. The structural wearable antenna assembly can have a thickness within a range of about 0.1 inches to about 2 inches. The length of the structural wearable antenna assembly can be within a range of about 5 inches to about 20 inches.
[0073] The microwave field stimulator can be located within a range from about 0.5 inch to about 12 inches from the embedded transmitting antenna. The thickness of the microwave field stimulator can be within a range from about 0.08 inches to about 0.39 inches. The length of the microwave field stimulator can be within a range from about 0.78 inches to about 2.75 inches. The width of the microwave field stimulator can be within a range from about 0.78 inches to about 2.75 inches.
[0074] The embedded transmitting antenna can have a length and width within a range from about 2 inches to 7 inches. The embedded transmitting antenna can have a thickness within a range from about 0.08 inches to about 0.2 inches.
[0075] FIGS. 3A and 3B show examples of a static length structural wearable antenna assembly. A structural wearable antenna assembly may include locking slots for an adjustable strap, a replaceable battery, embedded flat wire connectors, an embedded user interface control panel, an embedded microwave field stimulator, an embedded coaxial cable, and an embedded transmitting antenna.
[0076] As illustrated by FIG. 3A , the top view of the structural wearable antenna assembly. The replaceable battery is connected to a battery dock that secures the battery. The battery dock uses flat wires that are embedded into the structural wearable antenna assembly to bring power through the control panel and to the microwave field stimulator. The control panel also utilizes multiple flat wires to connect to the microwave field stimulator. The microwave field stimulator outputs an RF signal through the thin profile coaxial cable that is embedded in the structural wearable antenna assembly to the transmitting antenna.
[0077] The locking slots are located at opposite horizontal ends of the wearable antenna assembly and connect to an adjustable strap to allow for greater flexibility between patients of different waist sizes.
[0078] As illustrated by FIG. 3B , the profile view of the structural wearable antenna assembly. The replaceable battery is locked into the embedded dock. The control panel shows very low profile buttons that are used to control the microwave field stimulator. The microwave field stimulator and embedded antenna show a very low profile that allows the device to conform well to the patient and remove obstructive extrusions. Structural belt has conforming curves that allow the transitions of thicknesses of the various components to be smoothed out. The conforming curves aid the patient in avoiding the belt getting caught onto corners and edges of objects that a patient may daily interact with.
[0079] FIGS. 4A , 4 B, 4 C show examples of a control panel for the WAA. A control panel may include button-switches to control neurostimulation settings, and a sliding switch that chooses the setting that is being controlled by the switches.
[0080] As illustrated in FIG. 4A , the WAA may include only two button-switches. These two-button switches may control the amplitude, pulse width, frequency, or preset programs of stimulation. The switches can be labeled with directional arrows or plus and minus features. In certain embodiments, there may be more than two button-switches that can control a number of parameters from the microwave field stimulator.
[0081] These soft button-switches, allow the user to increase (+) or decrease (−) the amplitude of the parameter. In certain embodiments, the soft buttons are placed at the top of the belt, allowing the user to see the buttons and select the correct change for the selected parameter. The soft buttons also feature an embossed + and − so that the user can develop a sensory adaption to the parameter change button without relying on sight.
[0082] As illustrated in FIG. 4B , the WAA may include a sliding switch that chooses the setting that is being controlled by the switches. The sliding switch can act as an on/off toggle, in this embodiment the slider is pushed all the way to one end, which interrupts all power and stops stimulation. The sliding switch, when not in the off position, will begin stimulation. The slider can toggle button-switches to adjust specific parameters such as amplitude of power, pulse width, frequency, or preset parameters. The toggle switch is positioned in the front face of the belt, which allows the user to see the switch or rely on sensory feedback of the switches resistance to being thrown into position.
[0083] As illustrated in FIG. 4C , the control panel is streamlined and integrated into the belt. This module is positioned between the microwave field stimulator and the battery on the belt and is accessible at the front of the belt. The user can use tactical sensory feedback when operating the control panel. The toggle switch and the soft buttons make the control panel distinguishable from the microwave field stimulator and the battery. The control panel's width and length can be within the range from about 0.5 inches to about 2.0 inches. The control panel's thickness can be within the range from about 0.08 inches to about 0.5 inches. In certain embodiments, the control panel may have multiple indicator lights used to inform the user of system functions.
[0084] FIG. 5 depicts a block diagram of the structural layers of a flexible transmitting antenna. The flexible transmitting antenna is composed of a conductive layer pitted between equal layers of moldable foam with a ground plane and a dielectric matching layer that is placed against the back of the user. The transmitting antenna is tuned with a dielectric material to match the coupling of the user's skin eliminating the need for a gel to facilitate transmission.
[0085] As shown in FIG. 5 , the conductive layer of the transmitting antenna is composed of a conductive material such as copper, gold, etc. The foam layers are comprised of non-conductive materials such as polyimide and secured to the conductive layer with a thin layer of adhesive. The antenna is capable of transmitting energy through the body to the implanted lead because of the dielectric matching layer. This layer is affixed to the transmitting antenna and is in contact with the body while the WAA is worn. The antenna can be comprised of a conductive layer pitted between two layers of moldable foam. This antenna construction permits the antenna to be shaped and formed to fit flush against the back of the user eliminating air gaps. The ability of the dielectric to match the permittivity of the body allows the antenna to perform without the assistance of a gel applied to the body to maintain contact between the skin and the antenna.
[0086] FIG. 6 illustrates a design of the WAA to have a secondary battery dock which allows the user to hot-swap batteries for continuous neurostimulation. A WAA may consist of two embedded battery-docking stations. Once the primary battery connected to the MFS is close to drained and the user is informed via LED or notification to smart phone via Bluetooth, the user can place a fully charged secondary replaceable battery into the secondary battery dock to continue stimulation. The user can disengage the drained battery from the belt, once the fully charged battery is in place. The belt-mounted secondary battery dock is positioned next to the primary battery-dock on the user's front side of the belt.
[0087] The stationary battery docks' connections can be placed in parallel so that the voltage to the MFS is not doubled, but rather the capacity is increased. In certain embodiments, a user can have both the primary battery and secondary battery engaged on the WAA to extend the overall charge life of the device.
[0088] FIG. 7 illustrates an adjustable coaxial cabling method used for circumferential length adjustability of the structural belt. This embodiment of the structural belt includes a microwave field stimulator that can be moved along the circumferential axis of the belt, while the embedded antenna is stationary. The coaxial cable is wound around a small flexible rod that is secured to the structural belt at one end. The rod releases wound cable at one end, allowing the user to wind or unwind the cabling from the rod and adjust the location of the microwave field stimulator for best comfort. The amount of adjustable length added from the rod can be within the range from about 0.5 inches to about 6.0 inches.
[0089] FIG. 8 illustrates an adjustable coaxial cabling method in a flexible structural belt to allow flexibility when the belt is stretched. A flexible structural belt can maintain the integrity of the coaxial cable's connectors when the patient is stretching the WAA around the waist. The coaxial cable is wrapped around cleats that are attached to multiple scissor hinges. The scissor hinges are mounted to the flexible structural belt, and when stretched the scissor hinges expand and the cabling woven over the cleats is elongated. The cleat-scissor mechanism allows circumferential length adjustability from about 0.01 inches to about 2.0 inches.
[0090] FIGS. 9A to 9E demonstrate the tensioners used to ensure that shape of an embedded antenna is maintained while the belt is worn by the user.
[0091] FIG. 9A illustrates an embedded antenna while the pull-string tensioners are not engaged and the embedded antenna is flat. When the two strings are pulled tight, the low-profile cleats pull the structural belt together to push the embedded antenna convexly into the crevice of the lumbar region of the patient, as depicted in FIG. 9C . The locking modules hold the strings in place so that the tension is maintained, as depicted in FIG. 9B .
[0092] FIG. 9B illustrates an embedded antenna while the pull-string tensioners are engaged and the embedded antenna's flexible shape is maintained.
[0093] FIG. 9C illustrates a WAA on a patient where the pull-string tensioners are engaged and the embedded antenna's flexible shape conforms to the lumbar crevice of the patient.
[0094] FIG. 9D illustrates an embedded antenna while the Velcro straps are not engaged and the embedded antenna's flexible shape is not maintained. When the Velcro straps are connected, the sewn-in anchors of each strap pull the structural belt together to push the embedded antenna convexly into the crevice of the lumbar region of the patient.
[0095] FIG. 9E illustrates an embedded antenna while the Velcro straps are engaged and the embedded antenna's flexible shape is maintained.
[0096] FIG. 10A illustrates a WAA with a two-piece antenna with interlocking fingers that give greater conformity to the lumbar crevice. The interlocking fingers of the antenna automatically adjust to the patient according to the tightness of the WAA. As the patient tightens or loosens the adjustable portion of the WAA, the interlocking fingers push together to either go convex or concave into the lumbar crevice.
[0097] FIG. 10B illustrates a two-piece antenna with interlocking fingers that adjust along the caudal-cranial axis. The antenna is composed of the flexible conductive layer between the two, polyamide foam layers secured with an adhesive. The antenna comprises of two pieces that lock together. The interlocking ends can flex to conform to the crevice of the user's back. The antenna will lock tight, but flexibility of the antenna will be maintained at the ends of the antenna to encourage elimination of air between the antenna and the user's back.
[0098] FIG. 11 demonstrates the use of a soft sleeve that is slipped over the structural portions of the WAA. The sleeve has an opening at each end and shaped to identify the end that is intended for the antenna and an opening for the toggle switch of the control module. The sleeve is tubular, designed to fit tightly to the structural belt and to provide additional cushioning for user comfort. Additionally, this tight fitting sleeve streamlines the modules of the belt for concealing the belt under clothing. The sleeve material can be a water resistant, soft, flexible material such as neoprene or nylon with elastic support threads. The sleeve is machine washable.
[0099] FIG. 12 demonstrates the implementation of an elastic portion into a structural belt to increase flexibility between user positions. This WAA uses snap-in connectors to secure the structural belt around the user. The adjustability of the WAA is isolated to only one side of the belt allowing the user to easily adjust the fit of the belt for comfort, and removal when necessary. The user of a singular point of adjustability eliminates user errors, or risk of incorrectly adjusting the belt on the body. The combination of elasticity and adjustability provides secure fit of the belt to the body when the user is changing positions, i.e. standing to sitting, standing to bending over, sitting to bending over, etc.
[0100] FIG. 13 illustrates various patch antenna shapes that can be used in the wearable antenna assembly. The interlocking fingers antenna, square antenna, diamond antenna, and rectangular antenna are examples of antennas for the WAA.
[0101] FIG. 14 depicts the use of venting holes in the wearable antenna assembly to encourage the evaporation of sweat and increase the breathability of the assembly. The structural belt has perforations in the elastomer to permit airflow to the skin. The ventilation holes permit the flow of air to the covered area of the skin, which allows natural body perspiration to cool the surface temperature. The holes are placed at modules that are potential heat generating modules to ventilate the areas that are more susceptible to perspiration.
[0102] FIG. 15 is an example of fasteners used to secure the wearable antenna assembly to the patient. Locking fasteners such as a tab-slot hole design, a parachute clip, or a Velcro strap may be used on the WAA. A sliding clip can be used to adjust the circumference of the WAA. The fastening methods are easily operated while the belt is worn on the body. The fastener will be secured at the front and adjusted at the side of the user, which should not impede dexterity when attempting to remove or adjust the fit of the belt.
[0103] FIG. 16 illustrates a wearable antenna assembly that is condensed to fit into the shape of a standard watch. A watch that contains an embedded antenna, microwave field stimulator, button controls, and replaceable battery can be used to deliver RF to an implanted lead module for peripheral nerve stimulation. The transmitting antenna is formed into the straps of the watch, with the microwave field stimulator, battery, and button controls are incorporated into the face of the watch. The wristwatch may have an LCD display screen that will visually communicate the stimulation, pulse width, and frequency parameters for the user to update with the buttons, and have functionality similar to standard watches including time, stopwatch, countdown timer, alarm, date, etc.
[0104] FIG. 17 illustrates a fabric-antenna made of micro-conducting fibers woven into a structure of fabric to create a flexible antenna. The conductive threads can be made of conductive materials such as gold, copper, etc. The conductive threads are woven into fabric threading to create a flexible and thin patch of conductive material. For tuning of the antenna to specific frequencies, the material would be trimmed or cut to the required length. The conductive fabric is then used transmit an RF signal directly to the implant at various locations on the body where fabric is found, including but not limited to: lumbar, thorax, stomach, chest, shoulder, arm, forearm, leg, foot, hand, neck, buttocks, etc. The microwave field stimulator would be implemented into a separate belt or clip that is held comfortably at the waist or in the pocket.
[0105] FIGS. 18A and B illustrate the implementation of an antenna that is deposited into a WAA.
[0106] FIG. 18A illustrates the process of depositing materials to create the antenna stackup. The structural belt is sprayed with micro-drops of a liquid contained under pressure for precise placement. The deposit made by these liquids once dry will form the dielectric and conductive materials of the antenna. This eliminates the need for pitting the antenna into the belt. The cabling is run through the belt with a coaxial cable connecting to a copper or gold connector built into the belt. Once sprayed with the liquid, the antenna will be affixed to the coaxial cable.
[0107] FIG. 18B is a block diagram depicting the antenna layers for an assembly where the dielectric, conducting planes, and foam are deposited in to create an ultra thin profile. The transmitting antenna is spray molded into the structural belt through spraying in the layers of the antenna to form the antenna to the exact shape of the belt. The conductive ground layer is sprayed in first, followed by the layer of sprayed polyamide foam. Once dry the conductive layer is sprayed in followed by a second layer of polyamide foam. Once dry, the matching dielectric layer is laid over the sprayed antenna concealing the antenna from the user. The cabling is run through the belt with the coaxial cable connecting to a copper or gold connector built into the belt. Once sprayed with the conductive liquid, the antenna will be affixed to the coaxial cable.
[0108] FIG. 19 illustrates a semi-cylindrical array of antennas that are used to transmit power to the implant. The semi-cylindrical antenna array is comprised of smaller patch antennas that act as a single antenna to transmit RF energy to an implanted lead. The smaller antennas are arranged to direct or steer the energy directly to the implant. The smaller antennas have small space between them to improve the flexibility of the WAA and conformity of the antennas to the body. Each antenna is moldable and would conform to the back and body of the user. The moldability of many small antennas improves the ability of the patient to correctly place the belt on the body after removal.
[0109] FIG. 20 illustrates a molded antenna that is snapped into the wearable antenna assembly. A snap-in molded antenna is composed of flexible conductive layers pitted between two layers of moldable dielectric foam attached with adhesive. The patch is moldable and attached to the structural belt with elastomer teeth. The antenna can be molded independently from the belt, allowing the user to conform the antenna to their body without the risk of the antenna relaxing its shape due to tension from the belt. The belt will fit snug on the user, while maintaining constant contact of the antenna on the user.
[0110] FIG. 21 is an example of a molded antenna that conforms to the lumbar crevice, and can be secured directly to tissue using suction cups. The suction-cup antenna is conformed and affixed to the users back with suction cups. The formable antenna is designed with rubber suction cups that are able to attach to the back of the user with applied force, creating a vacuum between the antenna and the user. This gives greater conformity of the transmitting antenna to the user's body and will stabilize the antenna over the implant. The suction-cup antenna is encapsulated with the matching dielectric and is connected via coaxial cable to the microwave field stimulator that is clipped to the belt or in the pocket.
[0111] FIG. 22 illustrates fluid wicking, hydrophilic micro-channels built in to the wearable antenna assembly to displace fluids that would otherwise disrupt the tuning of the antenna. The elastomer material of the structural belt may be affixed with moisture pads, made of an absorbent material that is flush with the belt surface. The micro-channels are hydrophilic and draw moisture, such as sweat, away from the antenna face, and direct the moisture through the long narrow channels pitted into the structural belt to the washable moisture pads attached on the inside of the belt. In certain embodiments the water micro-channels would be located around the circumference of the WAA, without the use of moisture pads, to displace moisture to less moist regions of the WAA.
[0112] FIG. 23 is a block diagram depicting the antenna layers for an implementation where perspiration is used in the tuning calculation of the dielectric within the wearable antenna assembly. In this embodiment, the embedded antenna uses the permittivity of sweat as a form of matching dielectric to allow transmission of energy through the body. The secondary layer of matching dielectric is effective for transmission when the body is not perspiring. This layer is similar in permittivity to sweat, but not identical. The embedded antenna is designed with a conductive layer pitted between two layers of moldable foam. The moldable foam allows the antenna to be flexed and molded to match the shape of the users back. This body shaped antenna maintains contact with the skin encouraging body perspiration to match the dielectric for energy transmission.
[0113] FIG. 24 demonstrates an antenna array that can be used to select the antenna that is in the best position to power the lead and reduce reflection within the wearable antenna assembly. The WAA is designed to incorporate more than one embedded antenna to power the implanted lead. The transmitting antennas are small and are placed in the structural belt. The microwave field stimulator is able to power one, two, three or all four of the antennas to transmit the RF energy to the lead. The antenna array allows RF energy to be steered towards the implant. The microwave field stimulator can dynamically calculate the antenna that has the least amount of reflected energy and use the most efficient antenna to power the lead as the user moves around in their daily environment.
[0114] FIG. 25 is an example of a rotary mechanism that allows the antenna to be rotated by 270 degrees within the wearable antenna assembly. Migration of the implant in the body can require repositioning of the WAA antenna within the belt to avoid polarization of transmission and encourage optimized transmission. The embedded antenna is set into a circular housing in the WAA. The antenna is secured to the belt with a centered ball joint that allows rotational movement along the arced track of the belt. The antenna has a matching pin that aligns to the groove of the track of the belt. The arced track for rotation allows rotation between from about 0° to about 270°. The ball joint is designed with resistance so that movement of the antenna within the house must be deliberate, requiring force to move the antenna along the track. The coaxial cable for the transmitting antenna is run through the circular track of the belt. Any slack cabling is wound on its own ball joint, as the antenna rotates. Once the antenna is set at the appropriate rotation for transmission the antenna and cabling can be re-concealed with a sleeve or cover.
[0115] FIG. 26 demonstrates the use of two antennas to power two leads simultaneously with separate parameters and amplitudes in the wearable antenna assembly. The microwave field stimulator is able to program and transmit independent power parameters to the two implanted leads. This allows for control over two or more leads, implanted at different locations. The antennas are stacked and are able to be placed off center front the spine.
[0116] FIG. 27 is an example circuit that can be used to inform the user that RF energy is being transmitted. An indicator light is build into the control panel of the belt. This indicator light illuminates when the belt is transmitting energy to the implant. This indicator light is independent from the “power on” indicator. If the microwave field stimulator is not able to transmit power to the transmitting antenna, the indicator light will not illuminate. This indicator light will remain illuminated as long as RF energy is transmitted out of the embedded antenna. This indicator light can be a small LED, OLED, LCD, or a signal sent to a smart phone application via Bluetooth. The indicator light works through a small dipole placed at the edge of the embedded antenna, which receives the energy to power the indicator light. A resistor is used to tune the current to the indicator light.
[0117] FIG. 28 illustrates the use of signal rails within the belt to allow placement of the battery, control panel, and microwave field stimulator in interchangeable locations along the wearable antenna assembly. In this embodiment of the WAA, the microwave field stimulator, battery, and control panel are “floating” modules on the belt. These modules are secured to the belt via tracks and conduct energy/signal through the rails. In certain embodiments, the tracks are keyed so as to prevent incorrect orientation of the modules connecting to the wrong rails. The modules complete their circuitry once attached to the belt set into the tracks. The modules are then secured on the belt. The user is able to move the modules independent of each other allowing the user to place the modules on comfortable places on the belt. The various body sizes and shapes require the modules to be adjustable. The rails can be set for specific signals including but not limited to: battery-power, ground, button-switches, RF Signal, light indicator.
[0118] FIG. 29 is an example of the placement of the microwave field stimulator near the antenna on the wearable antenna assembly. The microwave field stimulator is positioned close to the transmitting antenna on the belt to reduce transmission loss from the cable. This allows for a shorter, lower-profile cable. The microwave field stimulator can be located on either side of the antenna. In certain embodiments, the microwave field stimulator may be located on the backside of the antenna.
[0119] FIG. 30 illustrates the use of differential positioning sensors placed on the wearable antenna to alert the user and adjust stimulation. The belt is affixed with positioning sensors that will alert the user if the belt shifts to a position on the body that could produce less than optimal transmission of RF energy to the implanted lead. The dorsal sensors can be placed on the belt close to the transmitting antenna. The ventral sensors can be placed at the belt clip or at the 180° mark from the antenna. The microwave field stimulator calculates the differential position between the ventral and dorsal aspects of the WAA and can alert the user when the WAA has shifted enough that transmission may be interrupted. The microwave field stimulator can calculate the differential position between the ventral dorsal aspects of the WAA and automatically adjust the amplitude when the user has changed positions that are known to need corrective actions. The indication to the user can be vibration from the microwave field stimulator. Until the user has corrected the placement, the microwave field stimulator can vibrate or alert the user through a smartphone app via Bluetooth.
[0120] FIGS. 31 and 32 show an example of a belt fastening system with sensor contacts to activate/deactivate wireless stimulating electronics. The fastener contains male electrical contacts on the female side of the parachute clip and female electrical contacts on the male side of the parachute clip. The contacts can be connected to the circuitry of the battery. When the parachute clips are engaged, the circuit is closed, allowing the battery to power the microwave field stimulator. Once the belt is unfastened, the circuit is open, disabling the power from the battery to the microwave field stimulator. In other embodiments the electrical contacts can be used as a smart sensor to notify the electronics that the user is going to take off or adjust the belt. The microwave field stimulator could then slowly power down the amplitude of stimulation to avoid uncomfortable VSWR interactions with the antenna and the patient.
[0121] FIG. 33 shows a top view of a wearable antenna assembly according to some embodiments of the present invention. As shown, a center portion 3300 is disposed toward the longitudinal middle of the wearable antenna assembly. Left portion 3310 and right portion 3320 are disposed at either longitudinal side of center portion 3300 . As control panel 3330 is provided on the top face of right portion 3320 . Fastening members 3340 are provided to allow fastening of an elastic belt or otherwise to the portion of the wearable antenna assembly shown. As such, the portion of the wearable antenna assembly as shown in FIG. 33 may be less than the full length of a full wearable antenna assembly. For example, the portion of wearable antenna assembly shown in FIG. 33 may be approximately 30 centimeters long. An elastic ban attached at each end to fastening members 3340 can then be provided to make the full length or circumference of the entire wearable antenna assembly the length desired. In some instances, an elastic band will be provided so that the entire wearable antenna assembly circumference including the elastic band and the portion shown in FIG. 33 will be wearable around the torso of a patient, as previously discussed. Nonetheless, other configurations are possible, such as using a different attachment to fastening members 3340 , different forms of fastening members than those shown in FIG. 33 , different lengths of attachments to fastening members 3340 , and a different length for the portion shown in FIG. 33 .
[0122] FIG. 34 shows a side view of a wearable antenna assembly according to some embodiments of the present invention. As shown, center portion 3300 is disposed longitudinally between left portion 3310 and right portion 3320 . As further shown, narrower portions between center portion 3300 and left portion 3310 and between center portion 3300 and right portion 3320 may be provided to allow the wearable antenna assembly to flex and contour to the patient's body. These portions may also or alternatively be provided as a flexible material, such as foam, rubber, or otherwise.
[0123] FIG. 35A shows a top view of a wearable antenna assembly with certain outer portions removed according to some embodiments of the present invention. As shown, center portion 3300 contains a MFS 3500 and a transmitting antenna 3505 . Transmitting antenna 3505 may be a patch antenna provided in the center of center portion 3300 . MFS 3500 may be a provided as a printed circuit board with various circuitry provided thereon. As shown, MFS 3500 may be provided as disposed essentially surrounding transmitting antenna 3505 . Left portion 3310 contains left battery 3510 . Right portion 3320 contains control panel 3310 as well as right battery 3520 provided below control panel 3310 .
[0124] FIG. 35B shows a bottom view of a wearable antenna assembly with certain outer portions removed according to some embodiments of the present invention. As shown, center portion 3300 contains MFS 3500 and transmitting antenna 3505 . Left portion 3310 contains wireless charging coil 3515 as well as left battery 3510 provided below wireless charging coild 3515 . Right portion 3320 contains right battery 3520 .
[0125] FIGS. 36A , 36 B, and 36 C show cross section cutaway views of portions of a wearable antenna assembly according to some embodiments of the present invention. FIG. 36A shows a cross section cutaway view of center portion 3300 . As shown, transmitting antenna 3505 is disposed in the middle of center portion 3300 . MFS 3500 is disposed in the area surrounding transmitting antenna 3505 . FIG. 36B shows a cross section cutaway view of right portion 3320 . As shown, right battery 3520 is provided therein, and control panel 3330 is provided on the top face of right portion 3320 . FIG. 36C shows a cross section cutaway view of left portion 3310 . As shown, left battery 3510 and wireless charging coil 3515 are provided therein.
[0126] FIG. 37 shows a longitudinal cutaway view of a wearable antenna assembly according to some embodiments of the present invention. As shown, transmitting antenna 3505 and MFS 3500 are provided in center portion 3300 . As shown, right battery 3520 and control panel 3330 are provided in right portion 3320 . As shown, left battery 3510 and wireless charging coil 3515 are provided therein are provided in left portion 3310 .
[0127] FIG. 38 shows an exploded 3 D view of a wearable antenna assembly according to some embodiments of the present invention. As shown, center portion 3300 , which contains MFS 3500 and transmitting antenna 3505 , may contain a top rigid cover 3810 and a bottom rigid cover 3815 . In such a configuration, top rigid cover 3810 and bottom rigid cover 3815 close around MFS 3500 and transmitting antenna 3505 to form a rigid, protective shell around those components. This is advantageous as the circuitry of MFS 3500 and the thin surface of transmitting antenna 3505 may be fragile or prone to damage if bent. This rigid shell along with the other components previously discussed may then be enclosed in top skin 3800 and bottom skin 3805 . Top skin 3800 and bottom skin 3805 may serve to maintain all of the various functional components contained an in place in the wearable antenna assembly. Furthermore, top skin 3800 and bottom skin 3805 may be provided as a flexible material. With such a configuration, the wearable antenna assembly shown in this figure may be sufficiently flexible to contour to the patient's body despite the rigid components contained therein. As such, the flexible material of top skin 3800 and bottom skin 3805 may allow the wearable antenna assembly as shown in this figure to be worn as a belt despite it containing various rigid components.
[0128] The construction and arrangement of the elements as shown in the exemplary embodiments are illustrative only. Although only a few embodiments of the present disclosure have been described in detail, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements. The elements and assemblies may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations. Additionally, in the subject description, the word “exemplary” is used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word “exemplary” is intended to present concepts in a concrete manner. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the preferred and other exemplary embodiments without departing from the scope of the appended claims. | A wearable device for facilitating neurophysiological treatment of a patient harboring an implanted neural stimulator is provided. The wearable device includes a transmitting antenna configured to accept one or more input signals and to transmit one or more electromagnetic signals to a neural stimulator that is implanted in a patient's body. The wearable device further includes a control circuitry configured to provide the one or more input signals to the transmitting antenna. The wearable device further includes a battery that provides electrical power to at least the control circuitry. The wearable device is configured to be worn outside the patient's body. | 0 |
FIELD OF THE INVENTION
This invention relates to transmissions of rotary power, and more particularly to the type of continuously variable transmission that transfers torque between moveable pulley sheaves by a plurality of progressively sized continuous bands.
BACKGROUND OF THE INVENTION
Recent advances in continuously variable transmissions of rotary power have provided substantial improvements in efficiency and service life. In particular, the transmission described in U.S. Pat. No. #5,324,239 issued Jun. 28, 1994 (Van Blaricom) provides a unique and efficient means of transmitting torque at continuously variable speeds. This transmission transfers power between two sets of "V" shaped moveable pulley sheaves by a plurality of continuous bands that are radially dispersed about and operationally joining the moveable sheaves. The bands are sized progressively in circumference so that one may fit inside the other, and in width so that uniform frictional contact can be made with the pulley sheaves. In effecting a change in transmission speed ratio, one set of pulley sheaves are forced closer together and the other further apart. The radius of placement of each band increases on the sheaves that are forced together and decreases on the sheaves that are forced apart. Because the bands are placed one inside the other, they are sized differently in length and must run on different radii about the pulley sheaves. Because they are sized differently in length and run on different radii it can be shown by geometry that they must travel about the pulleys at slightly different speed ratios relative to one another when the overall transmission s ratio is other than one-to-one. This variation in speed ratio from band to band is small in the lower ratios of overall power transmission. In the higher ratios of overall power transmission the variation in speed ratio from band to band increases significantly, resulting in an increased sliding friction at the interface of the bands and pulley sheaves. This sliding friction reduces the efficiency of the transmission and shortens the service life, especially when a large number of bands are used for the purpose of transmitting high torque.
A small number of bands may be used when the torque requirement is relatively low. With the use of a small number of bands the innermost and outermost bands can be spaced relatively close together on their respective radii about the pulley sheaves, making them similar in geometry. Because they are similar in geometry, the variation in speed ratio between bands is small, making the resulting sliding friction of less consequence. When a large number of bands are used for the purpose of transmitting high torque however, the spacing between the innermost and outermost bands must be further apart due to the larger number of bands, resulting in radii of travel that are less similar. The variations in speed ratio between bands becomes more pronounced with a corresponding reduction in efficiency and service life.
While the above described transmission provides a substantially efficient means of providing continuously variable rotary power in the lower overall transmission speed ratios and with a small number of bands, there remains a need for means to reduce or eliminate the variations in speed ratio from band to band so that a large number of bands can be used to provide an increased torque capability without reducing efficiency and service life.
SUMMARY OF THE INVENTION
A primary object of the present invention is to provide an improved efficiency in a multiple band continuously variable transmission.
Another object of the present invention is to provide an improved service life in a multiple band continuously variable transmission.
Another object of the present invention is to provide an improved torque capacity in a multiple band continuously variable transmission.
These and other objectives are achieved in the present invention which provides pulley sheaves with radially contoured faces that operationally force a plurality of bands on to specific radii on the pulley sheaves. During a change in overall transmission speed ratio, the bands follow the contours of the pulley sheave faces. The contoured faces force the bands progressively closer together on the pulley with the smaller radii of band placement, and progressively farther apart on the pulley with the larger radii of band placement. Each band is forced on to radii which by geometry provides substantially the same speed ratio for each band throughout the range of overall transmission speed ratios.
The above objects and features of the invention as well as additional ones are described in detail below with reference to the preferred embodiment which is illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a section through the pulley sheaves' centerline of a transmission of the prior art with pulley sheave faces that have a straight profile. Three bands are shown for purposes of clarity. The positions of the pulley sheaves and bands are shown at the highest speed ratio.
FIG. 2 shows a section through the bands' centerline of a transmission of the prior art at the highest speed ratio. Again three bands of are shown for purposes of clarity.
FIG. 3 shows a section through the bands' centerline of a transmission of the prior art at a one-to-one speed ratio.
FIG. 4 shows a section through the pulley sheaves centerline of a transmission of the present invention with pulley sheave faces that have a contoured profile. The positions of the pulley sheaves and bands are shown at the highest speed ratio. Three bands are shown for purposes of clarity.
FIG. 5 shows a section through the bands' centerline of a transmission of the present invention showing the positions of the bands at the highest speed ratio. Again three bands are shown for purposes of clarity.
FIG. 6 shows a section through the bands' centerline of a transmission of the present invention showing the positions of the bands at a one-to-one speed ratio.
FIG. 7 shows a detail of a section through the driven pulley sheaves' centerline of a transmission of the present invention that illustrates the face profiles of the radially contoured pulley sheaves.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 through 3 of the drawings show a transmission of the prior art in which the numeral 1 refers to drive pulley sheaves that have faces with a straight profile and the numeral 2 refers to driven pulley sheaves that have faces with a straight profile.
FIGS. 4 through 6 of the drawings show a transmission of the present invention in which the numeral 3 refers to drive pulley sheaves that have faces with a contoured profile and the numeral 4 refers to driven pulley sheaves that have faces with a contoured profile.
FIG. 7 of the drawings shows a detail of a section through the driven pulley sheaves centerline of the present invention in which the numeral 4 refers to driven pulley sheaves that have faces with a contoured profile.
In FIGS. 1 through 6 of the drawings the numeral 5 shows three bands that are radially dispersed about the drive pulley sheaves and the driven pulley sheaves of their respective transmissions. The bands are placed one inside the other and are sized progressively in width so that uniform frictional contact can be made with the pulley sheave faces.
In FIGS. 1 and 4 of the drawings, the numeral 6 shows hydraulically operated means to slidably move the sheaves closer together or further apart.
Referring to FIG. 3 in which a transmission of the prior art is seen in cross section through the bands centerline at a transmission ratio of one-to-one, the bands 5 are shown to be equally distant from each other on the drive pulley sheaves 1 that have a straight profile and on the driven pulley sheaves 2 that also have a straight profile. It can be shown by geometry that each individual band runs at an exact one-to-one ratio between pulleys when the radial placement of an individual band on the drive pulley sheaves 1 and the driven pulley sheaves 2 is the same. In FIG. 6 a transmission of the present invention is also shown in cross section through the bands' centerline at a transmission ratio of one-to-one. The bands 5 are shown to be at equal distances from each other on the contoured drive pulley sheaves 3 and driven pulley sheaves 4. The radial placement of each band is the same on said sheaves and like the transmission of the prior art the speed ratio between pulleys for each band can be shown by geometry to be one-to-one.
Referring now to FIG. 1 in which a cross section of a transmission of the prior art is shown through the pulley sheaves' centerline, the transmission is shown at the highest overall speed ratio. The straight profiles of the pulley sheaves have forced the bands 5 on to radii that are equal distances apart on both the drive pulley sheaves 1 and the driven pulley sheaves 2. The equal spacing of the bands 5 may also be seen in FIG. 2, which is a cross section of a transmission of the prior art through the bands' centerline that is also at the highest overall speed ratio. Because the bands 5 are spaced equal distances from each other, it may be shown by geometry that said bands do not run at equal speed ratios relative to each other. They can only run at equal speed ratios when the overall transmission speed ratio is one-to-one as shown in FIG. 3. At overall transmission speed ratios that are other than one-to-one the ratio of the radius of placement on the drive pulley sheaves 1 and the radius of placement on the driven pulley sheaves 2 becomes different for each band. In operation these differences in the ratio of band placement radii cause differences in the speed ratio from band to band, which results in sliding friction at the interface of the bands and the pulley sheave faces. This sliding friction causes wear and reduces the efficiency of the transmission.
Referring now to FIG. 7 which shows a section through the driven pulley sheaves centerline of a transmission of the present invention, the numeral 4 shows driven pulley sheaves each with a specifically contoured face profile. Said specifically contoured face profile approximates certain portions of an ellipse. This profile can be more accurately described in the preferred embodiment by the quadratic equation y=6.5654X 3+10.899X 2+8.137X+0.0002, where X and Y are zero at the point on the profile where the center-most band runs when the transmission is at a one-to-one ratio. The above described profile is a mirror image on each opposing sheave half, and the driving and the driven pulley sheaves have the same profiles. FIG. 4 shows a transmission of the present invention at the highest overall speed ratio. The contoured faces of the drive pulley sheaves 3 and the driven pulley sheaves 4 have forced the bands 5 on to radii that are a greater distance apart on the drive pulley sheaves 3 than on the driven pulley sheaves 4. It may be shown by geometry that the ratio of the radii of placement on the drive pulley sheaves 3 and the radii of placement on the driven pulley sheaves 4 is substantially the same for each band. Because the ratios of the radii of band placement are substantially equal, the bands 5 run at substantially equal speed ratios between pulleys relative to each other. In the transmission of the present invention this may be said to be true at all overall speed ratios. The greater distances between the bands 5 on the drive pulley sheaves 3 relative to the driven pulley sheaves 4 can also be seen in FIG. 5, which is a section through the bands' centerline of a transmission of the present invention which is also at the highest overall speed ratio. The distances between the bands 5 of the present invention are also slightly progressive at ratios other than one-to-one, however the progression is slight and is therefore not illustrated in the drawings. Also not illustrated are the positions of the bands 5 at the lowest overall speed ratio, which is simply a reversal of the bands' positions on the pulleys at the highest overall speed ratio. Because the individual bands of the present invention run at substantially equal speed ratios between pulleys throughout the range of overall transmission speed ratios, the wear and inefficency caused by sliding friction is substantially eliminated.
The above described embodiment of the subject invention uses pulley sheave face contours in which the determining profile has been described herein by a quadratic equation. It is conceivable that others may improve upon these contours to provide additional enhancements to the operation of the transmission.
It is also conceivable that a contour be provided to only one sheave half per pulley set to provide equal ratios between bands.
It is also conceivable that the drive sheaves and the driven sheaves be sized differently, with different but complimentary sheave contours to provide equal ratios between bands.
Additional embodiments of this invention will be conceived by others, therefore it is intended that the scope of the invention be limited only by the following claims, and not by the embodiments described above. Reference should be made to the following claims in determining the full scope of the invention. | An Improvement in a multiple band continuously variable transmission that provides equal speed ratios for each band throughout a range of overall transmission speed ratios through the use of radially contoured pulley sheaves, | 5 |
BACKGROUND OF THE INVENTION
1. Field of the invention
The present invention relates to the protective mechanism comprised of a padlock and hasp, and in particular to a hasp which protects and enhances the effectiveness of such mechanism.
2. Description of the prior art
Standard-type hasps are built around two basic sections called herein a linking section and a hinged section, and the usual mode of coupling the two sections is by means of a U-shaped metal rod, the extremities of which are rigidly connected to the linking section in such position that the curved mid-portion is extended upward and can be caused to protrude through a rectangular hole in the movable tongue of the hinged section; a padlock then being linked with the protruding curve of the rod to secure the coupling.
The above is the most familiar type of standard hasp, but there are others which differ somewhat. One such is the hasp which employs a part resembling an eye-bolt in place of the U-shaped rod mentioned above. The stem of this "eye-bolt" is connected to a swivel-base which is held by spring pressure in either of two positions 90 degrees horizontally removed from one another. In one of said positions the vertically upraised "eye" may pass freely through the hinged tongue's rectangular hole, but in its alternate position the "eye" prevents either a coupling or un-coupling of the hasp's two sections, thus enabling this type hasp to function effectively as an independent latching device.
In general, standard hasps are characterized by the fact that they, and any attached padlocks, are extremely vulnerable to a twisting and/or prying attack delivered by means of a steel bar inserted through the opening afforded by the arm of a padlock.
SUMMARY OF THE INVENTION
Like the standard hasp, this hasp has a linking section and a hinged section; however, the means of coupling the sections of this hasp is unique: coupling is effected by the protrusion of a swivel-mounted "stud" of the linking section through a circular hole in the hinged section's tongue. The stud is formed from a rectangular strip of tough, malleable metal (mild steel, etc.), and this strip is particularly dimensioned so as to possess desired bending potential. An open channel through the stud's center is dimensioned to afford only that space considered necessary for maneuvering the arm of a padlock therein. The swivel-action of the stud protects the hasp-padlock against a twisting, shearing attack with a steel bar, etc., but equally advantageous is the fact that in the case of a prying, pulling attack upon the padlock, the swivel allows the stud to allign itself in such direction that the stud's rectangularly cross-sectioned material may most readily bend and thereby relieve tension which would otherwise be concentrated largely within the lock's mechanism. Similarly, the hinged tongue is provided with forty-five-degree down-turned bends across its outer end and along portions of each side which cause these areas to offer precarious footing and weak support for a prying implement.
Various construction details facilitate and protect the bending and swiveling qualities mentioned above, and the net result is a hasp which has a calculated tendency to yield to, rather than resist, the prying-twisting assaults commonly used to defeat the standard hasp-padlock mechanism.
Accordingly, a primary objective of the invention is to provide a hasp which is much less vulnerable to an attack by the usual methods, and which will compell a potential burglar or thief either to consume more time and energy in overcoming the hasp-padlock mechanism in the usual manner, or to adopt and familiarize himself with different tools and techniques; either alternative resulting in his exposing himself to increased risk of discovery or detection.
A further object of the invention is to provide a hasp which, while affording unique protection to an attached padlock, retains sufficient resemblance to standard hasps as to permit its being manufactured with no great departure from established production and assembly procedures.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, which demonstrate the working principles of the hasp but which must be appropriately scaled to accomodate padlocks having various arm-diameters:
FIG. 1 is a side elevational view of the hasp's two sections less mounting screws; however, in order to represent details of the Linking Section more clearly, this drawing shows the Tongue 18 as it would appear before 45-degree bends are made along portions of each side thereof; also, the Disc 12 is shown as being somewhat smaller than it would actually be,
FIG. 2 is a diagramatic plan view of the hasp's two sections less mounting screws, and this view, in conjunction with the view in FIG. 1, shows the correct relative positions of the two sections;
FIG . 3 is a plan view of the Disc 12;
FIG. 4 is a side elevational view of the Disc 12;
FIG. 5 is an enlarged plan view of the Stud 11, with the arm of a padlock linked thereto; this view shows factors influencing the dimensions of the Stud's Channel 14.
DESCRIPTION OF PREFERRED EMBODIMENTS
All critical dimensions of the presently invented portion of this hasp are derived either directly or indirectly from the diameter of the padlock-arm a particular construction of the hasp must accomodate.
The Linking Section is comprised of the Stud 11, the Disc 12, and the Foundation Plate 13.
The Stud 11, FIGS. 1, 2 and 5, is constructed, preferably, from a rectangular strip of tough, malleable metal such as mild steel, etc., the width of which strip is equal to the diameter of the padlock-arm to be accomodated plus or minus a maximum of twenty-five percent, and the thickness of which is not less than one-third nor more than two-thirds the width thereof. The width of the Channel 14, or the horizontal distance between the Legs 15 and 16, FIGS. 1 and 5, and, hence, the radius of the curved, upper portion of the Stud 11, are determined as indicated in FIG. 5 where the value of D is self-explanatory, but where M is maneuvering space allowed for the lock-arm, and is not less than 1/32 inch nor more than 3/32 inch. Using the width and radius thus determined, the Stud's strip is bent to the shape indicated in FIG. 1, and allowance must be made to insure that, with the two sections coupled as in FIG. 1, the vertical measurement between point 17 (the interior peak of the curve) and the upper surface-level of the Tongue 18 is equal to the above described width of the Channel 14. Feet 19 and 20, FIGS. 1 and 5, project at right angles to, and for equal-minimum distances of 1/16 inch from their respective Legs, and the horizontal distance between the outer, center extremities of said feet is the Span of the Stud 11.
The Disc 12, FIGS. 3 and 4, is built of metal similar in nature and equal in thickness to that used for the Stud 11, and the Disc's diameter is equal to the above described Span of the Stud 11. The Bridge 21, FIG. 3, bisects the Disc, and separates the Slots 22 and 23 by a distance equal to the previously described width of the Channel 14, FIGS. 1 and 5. The Slots 22 and 23 are dimensioned to receive the Feet 19 and 20 of the Stud 11, as indicated in FIGS. 1 and 2, and the Stud and Disc are permanently joined by welds at 24 and 25, FIG. 3.
The Foundation Plate 13, FIGS. 1 and 2, is built, preferably, from a harder, less malleable metal than that used for the Stud 11. It is formed as indicated to provide the Housing 26 which is dimensioned in depth and width to contain the Disc 12. Immediately above and concentric with the Housing 26 is the circular Stud Hole 27, the diameter of which is equal to the horizontal, diagonal distance between outer and opposite edges of the Legs 15 and 16, FIGS. 2 and 5.
The Tongue 18, FIGS. 1 and 2, is a part of the Hinged Section, and is constructed, preferably, from metal identical in both type and thickness to that used for the above mentioned Foundation Plate 13. Forty-five-degree down-turned bends along the dashed lines 28, 29 and 30, FIG. 2, cause the lower edges of these bent sections to lie in a plane approximately 1/16 inch above the lower surface of the Foundation Plate 13, as is indicated at 31, FIG. 1. The Triangular Notches 32, and Plugged Corners 33, FIG. 2, permit said bends to be made. The Tongue 18 must be of sufficient width that after the side bends 28 and 30 are made, adequate space remains between said bends to accomodate the circular Coupling Hole 34. The radius of this Coupling Hole is determined as follows: intersects with a vertical projection from that point on the circumference of the Stud Hole 27 most distant from the Hinge 35, and, therefore, Point X is the most extreme point which the Stud 11 will reach when revolved horizontally; the Radius 36 is adjusted so that the Arc 37 clears Point X by approximately 1/16 inch and Point 38 is where a projection of the Arc 37 would intersect with the lower surface of the Tongue 18; Point 39 is where the vertical axis of the Stud intersects with that same lower surface; by using the horizontal distance between Points 38 and 39 as a radius for the Coupling Hole 34, and using the vertical axis of the Stud 11 as the pivotal point therefor, the Coupling Hole thus obtained will permit a coupling or un-coupling of the hasp's two sections, regardless of what position the Stud might be turned to.
The sections of this hasp are mounted to a structure exactly as those of a standard hasp would be, and for this purpose countersunk holes dimensioned to accomodate 5/32 inch flathead screws are shown at 40 and 41, FIGS. 1 and 2.
While this hasp's swivel remains functionable, the hasp-padlock mechanism is invulnerable to the type of twisting, shearing attack commonly used to defeat the standard hasp and its padlock, and for protection of this swiveling capacity the dimensions of the Channel 14, FIGS. 1 and 5, are kept to a practical minimum so that after the lock-arm is inserted, very little space remains for an object which might otherwise be intruded and used to prevent rotation of the Stud 11. Similarly, the down-turned sides and end of the Tongue 18, FIGS. 1 and 2, act as shields for the hasp's swivel; however, the primary function of these bent sections is to prevent the hasp itself being used as an effective base for a prying implement: the 45-degree slopes of these down-turned sections offer a precarious footing for a steel bar, etc., and should such a footing nevertheless be used, these bent and thereby weakened edges, when pried against, will tend to yield, or bend further, as pressure is applied.
In furtherance of the above mentioned yielding characteristic of the hasp, the swivel-mounting of the Stud 11 performs a second vital function: the swivel assures that when an attached padlock is pried against in the usual manner, the pull upon the lock will cause the Stud 11 to allign itself in a direction such that the width/thickness ratio of the Stud's material will offer the least relative resistance to bending, and the malleable quality of the material will enable the Stud to withstand a considerable amount of such bending, or yielding, without fracturing.
Another advantage of this hasp's construction is that the material of the Stud 11 lays relatively close against the arm of an attached padlock and is less exposed and accessible than is the U-shaped rod used by most standard hasps. | A hasp which by its potential for bending in certain vital areas, and by its permitting an attached padlock to swivel freely, will tend to frustrate those methods usually relied upon to defeat the standard hasp-padlock protective mechanism. | 4 |
REFERENCE TO RELATED APPLICATIONS
[0001] This non-provisional application claims priority under 35 U.S.C. 119(e) to Provisional Patent Application No. 61/325,406, filed Apr. 19, 2010, the contents of which are herein incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present disclosure generally relates to the Endoscopic Mucosal Resection (EMR), and more particularly, to over-sheath devices to aid in polyp resection & removal needle conjunction with endoscopic techniques.
BACKGROUND OF THE INVENTION
[0003] Endoscopic mucosal resection (EMR), which was developed as a therapeutic method for resection of flat or depressed lesions of the gastrointestinal tract (esophagus), has also come to be widely accepted as an effective treatment for early colon cancer. EMR can be curative when the cancer, limited to the mucosa, is completely excised and lymph node metastasis is absent. In recent years, progress has been made in the development of EMR techniques. Various techniques and instruments have been devised to make EMR safer and more effective. If a small polyp-like nodule is seen in the esophagus, an endoscopic mucosal resection (EMR) can be performed to try to remove it. The nodule is first injected with a solution that will decrease bleeding after the nodule is removed. This solution also forms a blister under the nodule to allow the physician to remove same without damaging the rest of the esophagus. Similar techniques are also utilized in the treatment of colorectal cancer.
[0004] Typical EMR procedures are conducted using a small cap (e.g., those provided by Olympus Corp. Tokyo, Japan) which has a small wire loop which fits on the end of the endoscope. The nodule is suctioned into the cap and the wire loop is closed while electro-cautery energy is applied. This is performed so that the tissue can be examined under a microscope to determine if all cancer (or dysplasia) has been removed. In order to utilize the aforementioned cap device to resect the desired tissue, the Cap is preloaded onto the distal end of an endoscope or colonoscope prior to insertion to the desired resection site. Once the sample has been resected the specimen or polyp is removed. In the event that the polyp or specimen is too large to be removed through the working channel of the endoscope/colonoscope, the endoscope/colonoscope must be entirely removed from the patient. If it is desirable to resect a second specimen from the patient, the physician must re-insert the endoscope/colonoscope once again to the desired location. This effort can be time consuming, particularly in the case of colorectal EMR where navigation is impaired by the tortuous nature of the anatomy.
[0005] A clinical need therefore exists for an EMR device which can improve the efficiency of EMR procedures, particularly colonic EMR procedures, by providing the physician with embodiments to remove sample specimens without needing to remove the endoscope/colonoscope after each sample acquisition.
SUMMARY OF INVENTION
[0006] The present invention provides devices and methods for facilitating EMR procedures. The devices of the invention include an over-sheath device having one or more channels/lumens and/or an end cap element for coupling to an endoscope or a working channel of a colonoscope. The devices of the invention allow resected polyps to be removed/retrieved without removing the endoscope. The devices of the invention also allow for the removal and retrieval of multiple polyps without having to remove and re-insert the endoscope/colonoscope.
[0007] In one embodiment, the invention provides an over-sheath device having at least one channel/lumen and including an end-cap element. The over-sheath device includes a flexible elongate member having proximal portion and a distal portion. A primary channel/lumen extends along the length of the elongate member, the primary channel/lumen having an inner surface and an outer surface defined by the elongate member. The proximal portion of the primary channel/lumen is configured for housing an endoscope or a channel of an endoscopic device (e.g., a working channel of a colonoscope). The distal portion includes a rigid or semi-rigid end cap element. In certain embodiments, the distal cap member is integrated with the elongate member of the over-sheath device to form a smooth transition between the elongate member and cap element. In other embodiments, the distal cap element is a separate element coupled or bonded to the distal portion of the device. The primary channel/lumen of the elongate member can have a C-shape or a U-shaped cross-section. Alternatively, the primary channel/lumen of the elongate member is an enclosed lumen.
[0008] The flexible elongate member of the over-sheath device can further include a secondary side channel/lumen disposed alongside the outer surface of the primary lumen and distally extending to the distal end of the end cap element. Preferably the secondary side channel/lumen has a diameter smaller than a diameter of the primary lumen. The secondary side channel/lumen can have a C-shape or U-shaped cross section. Alternatively, the secondary side channel/lumen of the elongate member is an enclosed lumen.
[0009] In certain embodiments, the secondary side channel/lumen includes a deflectable distal tip portion. In such embodiments, the flexible elongate member of the over-sheath device further includes a lumen disposed within a wall of the secondary side channel. This lumen extends alongside the secondary side channel in a distal direction to the distal end of the end cap element. The lumen houses a pull wire that is coupled (e.g., bonded) to the distal tip portion of the secondary side channel/lumen. The lumen/pull wire (extends in a proximal direction to an actuator configured for deflecting the distal tip of the secondary side channel/lumen (the secondary side channel/lumen also extending in a proximal direction alongside the lumen/pull wire)). In certain embodiments, the actuator is a push/pull handle that deflects the distal tip in outward, inward and neutral directions. For example, the handle can be configured to deflect the distal tip in an outward direction relative the end cap when the handle is pulled in an upward direction, and inward relative to the end cap when the handle is pushed in a distal direction. Alternatively, the push/pull handle is configured to deflect the distal tip in an inward direction relative the end cap when the handle is pulled in an upward direction, and outward relative to the end cap when the handle is pushed in a distal direction.
[0010] The invention further provides a device for endoscopic mucosal resection comprising a rigid or semi-rigid end cap. The end cap is configured for housing an endoscope or a channel of an endoscopic device (e.g., a working channel of a colonoscope) and includes a side channel that is either integrated into the end cap, or disposed within or along an outer surface of said end cap. The side channel is preferably a C-shaped or a U-shaped channel. The side channel can be used to pass ancillary devices alongside the endoscope/working channel to facilitate an endoscopic procedure.
[0011] The invention even further provides a dual-lumen over-sheath device without an end cap element. The dual-lumen over-sheath device comprises a flexible elongate member having a proximal portion and a distal portion, and a primary channel/lumen and a secondary side channel/lumen extending along the length of the elongate member. The primary channel/lumen extends along the length of the elongate member, and has an inner surface and an outer surface defined by the elongate member. The proximal portion of the primary channel/lumen is configured for housing an endoscope or a channel of an endoscopic device (e.g., a working channel of a colonoscope). The secondary channel/lumen is disposed alongside the outer surface of the primary channel. Preferably, the primary channel/lumen has a diameter greater than the diameter of the secondary channel/lumen. The primary channel can be a C-shaped or a U-shaped, or can be an enclosed channel. Likewise, the secondary channel can be a C-shaped or a U-shaped channel, or an enclosed channel.
[0012] In the various embodiments described herein, the flexible elongate member of the over-sheath devices are preferably made of a thermoplastic material comprising a helically braided configuration. In some embodiments, the helically braided configuration of thermoplastic material further includes a wound stainless steel filament wire. The end cap or semi-rigid end cap is preferably made of a material, including but not limited to, polycarbonate, polystyrene, polyamide, polyurethane, polyethylene, polypropylene or any combination thereof.
BRIEF DESCRIPTION OF DRAWINGS
[0013] The accompanying drawings which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings, like reference characters generally refer to the same or similar parts throughout the different views. The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention.
[0014] FIG. 1 is a drawing of an exemplary embodiment of the distal end of a dual-lumen over-sheath device according to the invention that includes a primary channel/lumen 12 , secondary side channel 13 having a deflectable tip portion 16 , and distal end an end cap 10 .
[0015] FIG. 2 is an enlarged drawing of “DETAIL A” of the embodiment shown in FIG. 1 .
[0016] FIG. 3 is a drawing of an end cap 10 according to the invention that includes a secondary side channel 13 having a deflectable distal tip 16 .
[0017] FIG. 4A is a drawing depicting an exemplary embodiment of a dual-lumen over-sheath device 20 without an end cap element, the over-sheath device including a C-shaped or U-shaped primary channel/lumen 12 and a C-shape or U-shaped secondary side channel 13 ; FIG. 4B is an enlarged drawing of the circled portion of the device depicted in FIG. 4A .
[0018] FIG. 5 is a drawing depicting an exemplary embodiment of a dual-lumen over-sheath device that includes an end cap 10 and a secondary side channel 13 that extends along the outer surface of the primary lumen 12 of the over-sheath to the distal end of the end cap 10 , and an ancillary device 18 (e.g., a retrieval basket or snare) being extended through the secondary side channel 13 .
[0019] FIG. 6 is a drawing of the deflectable tip portion 16 of a secondary side channel 13 for use with the devices according to the invention, the deflectable tip portion 16 including a lumen 17 disposed within and extending along the length of an outer wall of the secondary side channel 16 for housing a pull wire.
[0020] FIG. 7 is a drawing of a dual-lumen over-sheath device according to the invention fitted over the distal end of a working channel of an endoscope and coupled to an actuator 21 (e.g., a handle) for deflecting the distal portion 16 of the secondary side channel 13 of the device.
[0021] FIG. 8 is a drawing an exemplary embodiment of a dual-lumen over-sheath device without end cap, the over-sheath device including a C-shaped primary lumen 12 and an enclosed secondary lumen 22 disposed along an outer wall of the primary lumen.
DETAILED DESCRIPTION
[0022] Disclosed herein are devices and methods for resecting and removing tissue or aiding in the resection and removal of tissue from the digestive tract in human subjects.
[0023] The first embodiment of the device is illustrated in FIGS. 1 , 2 and 3 . The device design consists of a rigid or semi-rigid end cap element 10 at the distal device end. This cap transitions to a flexible over-sheath component which contains two lumens therein. The primary lumen 12 of the over-sheath is intended to house an endoscope 14 or working channel of a colonoscope 15 while the secondary side channel/lumen 13 is intended to be used for the insertion and or retraction of ancillary devices 18 such as snares, biopsy forceps, guidewires etc.
[0024] During the procedure, the physician will load the integrated end cap 10 and dual lumen over-sheath device 20 over the end of the endoscope 14 securing the end cap 10 to the end of the scope. The scope with preloaded end cap/over-sheath is then inserted to the desired anatomical site trans orally or trans rectally. Once in position the polyp or tissue sample may be elevated via media injection to elevate the mucosa and electro-cautery performed to excise the polyp. Instead of removing the entire device (end cap/over-sheath & endoscope) the physician can now pass an ancillary device 18 , such as a snare or retrieval basket (e.g., Roth Basket device, US Endoscopy) device through the secondary channel 13 of the over-sheath, as shown in FIG. 5 . The polyp or tissue sample is snared by the ancillary device 18 and retracted from the end of the scope. In some embodiments, the secondary channel 13 of the over-sheath is not an enclosed lumen, and has C-Channel or U-Shaped cross sectional profile. With such a profile, when the ancillary device 18 is retracted, the polyp and basket portion of the retrieval device 18 reside external to the secondary channel/lumen 13 . This allows the physician to completely remove large polyps from the intended site without the necessity of having to remove the endoscope to remove the polyp sample. In this way, procedural efficiency for the removal of multiple polyps is improved.
[0025] It is preferred that the EMR cap component 10 of the device be fabricated from a clear or translucent or semi-translucent material such as, but not limited to Polycarbonate, Polystyrene, Polyamide, Polyurethane, Polyethylene, Polypropylene and/or derivatives thereof.
[0026] In the embodiment shown in FIGS. 1 through 3 inclusive, the distal end cap element 10 is not completely enclosed but has a portion of the cross section removed. This section is removed to provide for the incorporation of a deflectable tip element 16 which extends from the secondary side channel 13 to the extreme distal end of the cap element 10 . This deflectable tip 16 is in constant communication with the lumen of the secondary outer channel 13 of the over-sheath and maintains a “C-Channel” or “U-Shaped” profile identical to that of the secondary over-sheath channel 13 . The deflecting tip portion 16 of the embodiment may be a separate component which may be attached to the secondary channel 13 of the over-sheath or alternately may be a continuation of the secondary channel 13 of the over-sheath.
[0027] As shown in FIG. 6 , the ability to deflect the distal tip portion 16 of the side channel 13 is achieved via the incorporation of a pull wire which is housed within a third lumen 17 of the over-sheath. The pull wire is anchored to the distal portion of the deflecting tip 16 via adhesive or thermal bonding techniques. The pull wire extends from the distal end of the deflecting tip portion 16 of the over-sheath in a proximal direction to an actuator 21 , such as a “push-pull” handle, as illustrated in FIG. 7 . Actuation of the proximal push-pull handle causes the deflecting tip 16 to deflect either outward or inward relative to the end cap 10 /over-sheath device. This embodiment of the present invention may be fabricated such that the deflecting tip 16 is preferentially loaded to deflect either inward or outward at neutral. This may be controlled when the device is manufactured by lengthening the pull wire (this will result in the deflecting tip deflecting inward when at neutral) or shortening the pull wire (this will result in the deflecting tip deflecting outward when at neutral).
[0028] The ability to deflect the distal tip 16 of the secondary channel 13 is an important characteristic of the present invention as it provides the user with the ability to lift mucosa during resection to improve the quality and quantity of the sample being resected, which is often cancerous. During resection, a biopsy forceps may be passed through the outer secondary channel 13 of the over-sheath and used as described above, using the deflectable functionality of the side channel 13 to lift the mucosa.
[0029] The elongate body of the over-sheath is preferably manufactured from a thermoplastic polymer such as, but not limited to Polyurethane, Polyamide and derivatives thereof, Ether block amide copolymers, Polyimide, Polyethylene and derivatives thereof, Polytetrafluoroethylene and/or derivatives thereof. In certain embodiments, the outer shaft of the elongate over-sheath over-sheath body comprises a helically braided configuration of outer thermoplastic material such as those mentioned above with a lubricious inner liner or core, which encases the helically wound braid detail. The helically braided element may further included braided stainless steel round or rectangular filament wire wound in a “2 over 2” fashion as is known to persons skilled in the art. The incorporation of this helically wound design detail allows the user to transmit a torsional load to the over-sheath assembly from outside the patient to aid in positioning the distal end cap 10 of the device for optimal use.
[0030] An alternate embodiment of the over-sheath aspect of the present invention is illustrated in FIG. 8 . In this instance, the secondary sided channel 13 of the over-sheath is of closed lumen 22 construction to provide the user with the ability to advance ancillary devices to the site of resection. In this instance, the embodiment does not incorporate a distal cap element.
[0031] In a number of instances, the physician may have positioned the endoscope/colonoscope during routine diagnostic procedures and decide that he/she wishes to perform a resection. In this instance, this over-sheath embodiment provides the user with the ability to load the over-sheath proximally over the elongate body of the endoscope external to the patient and, using the elongate body of the endoscope, track the over sheath to the distal end of the endoscope without the need to remove the scope. In this way, the procedure may be performed more efficiently while maintaining anatomical position. The secondary channel 13 of this over-sheath embodiment may also be of “C-Channel” or “U-Shaped” configuration as shown also in FIG. 4 .
[0032] It will be understood that various modifications may be made to the embodiments disclosed herein. Therefore, the above description should not be construed as limiting, but merely as illustrative of some embodiments according to the invention. | The present invention provides methods and devices for facilitating endoscopic tissue resection procedures. The devices of the invention include a flexible over-sheath having one or more lumens/channels and/or a rigid or semi-rigid end cap element for coupling to an endoscopic device. | 0 |
BACKGROUND OF THE INVENTION
The invention relates to an apparatus for monitoring the closed position of a locking gas cap, with a magnet disposed at or in the locking gas cap and a magnetic switch disposed at the tank connection pipe.
An apparatus of this type is described in the DE 44 04 014 A1 and serves to monitor the closed position of the locking gas cap of a motor vehicle so that, when the locking gas cap is not closed or closed incompletely, a warning signal appears on the dashboard of the vehicle.
In the case of the known apparatus, the locking gas cap has a bayonet catch and the magnet is disposed in such a manner, that it is in the vicinity of a reed switch, when the bayonet catch is locked. Depending on the construction, the reed switch is thus either open or closed when the locking gas cap reaches the locked position. Preferably, the reed switch is constructed so that it is closed in the locked position and that an associated evaluating circuit causes a warning signal to be displayed when the circuit of the reed switch is interrupted.
Since the magnetic field of the magnets cannot be localized to a narrow limited space, the position of the locking gas cap can be determined only relatively inaccurately according to this principle. For many tank caps, the locking gas cap is constructed as a screw-in plug. However, even in the case of bayonet-like tank caps, screw pitch surfaces are usually provided, which ensure that the plug, in the closed position, is pressed firmly against an associated seal. The possibility therefore exists that the locking gas cap is not turned completely into the end position, in which the tank opening is sealed reliably and in which a subsequent loosening of the locking gas cap due to vibrations is prevented because of the frictional engagement. However, because of the aforementioned inaccuracy in determining the position, the reed switch would also respond in such a case, so that the correct closing of the locking gas cap cannot be indicated reliably.
SUMMARY OF THE INVENTION
It is an object of the invention to make it possible to monitor the closed position of the locking gas cap with greater reliability.
Pursuant to the invention, this objective is accomplished owing to the fact that the locking gas cap has a torque limiter and the magnet is coupled with the torque limiter in such a manner, that it reaches a position, in which the magnetic switch is triggered, only when the limiting torque is attained.
By these means, it is ensured that the magnetic switch responds only when, while screwing in the locking gas cap, the limiting torque is actually reached and it is thus ensured that the locking gas cap is effectively closed tightly and completely.
A locking gas cap with a screw-in plug and a torque limiter is described already in DE 196 10 471 C2. This locking gas cap has a cap, which is rotatably disposed on the screw-in plug and is provided with a handle. The torque, which is exerted by the user on the cap, is transferred by the torque limiter to the screw-in plug. As soon as the limiting torque is exceeded when the closed position is reached, the cap rotates relative to the screw-in plug. In accordance with an advantageous development of the present invention, this relative movement is used for the purpose of transferring the magnet into the triggering position. Preferably, the magnet is held axially movable in the locking gas cap and, at the cap or at the plug of the locking gas cap, inclined surfaces are provided, which convert the rotation of the cap relative to the plug into an axial motion of the magnet. The magnet is pre-stressed elastically in the position at rest and is converted into the release position only when the limiting torque is reached by the inclined surfaces. At the same time, the inclined surfaces and the associated mating surfaces can be constructed in such a manner, that they can slide off one another when the cap is rotated further after it has reached the limiting torque. In this case, it is possible that the magnet springs back once again after it has exceeded the limiting torque and is removed from the release position. Preferably, this spring-back motion is, however, limited so that the magnetic switch, because of the magnetic remanence of the reed contacts, nevertheless remains closed. Only when the locking gas cap is loosened once again or removed completely, does the distance between the magnets and the magnetic switch become so large that the switch opens up. In this case, therefore, the magnetic switch exhibits some hysteresis behavior. It closes only when the limiting torque is reached or exceeded at least once, but then remains closed when the magnet once again is removed further from the magnetic switch.
Alternatively, an embodiment is also conceivable, for which the magnet, in the release position, is relatively close to a magnetizable body, so that, upon reaching the release position, it is held magnetically in the release position and springs back once again into the position at rest only when it is screwed out of the locking gas cap.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, examples of the invention are described in greater detail by means of the drawings, in which
FIG. 1 shows a section through a locking gas cap when the closed position in a tank connection pipe is reached and
FIG. 2 shows a section through the locking gas cap in a position after the limiting torque of a torque limiter is exceeded.
DETAILED DESCRIPTION
In FIG. 1, a locking gas cap 10 is screwed onto a connection pipe 12 of a fuel tank of a vehicle. The locking gas cap has a screw-in plug 14 and a cap 16 , which is connected rotatably with the screw-in plug and forms a handle 18 . In the opening of the tank connection pipe 12 , a threaded insert 20 is fastened, which has engaged the external thread of the screw-in plug 14 . FIG. 1 shows the locking gas cap in the closed position, in which a flange 22 of the screw-in plug, over a seal 24 , is in sealing contact with the edge of the threaded insert 20 .
In the interior of the screw-in plug 14 , a pot-shaped inner part 26 and, further to the outside, that is, further towards the top in FIG. 1, a guiding bush 28 is disposed, in which a magnet carrier 30 is guided axially movably. A magnet 32 (permanent magnet) is held with holding claws at the magnet carrier 30 and lies within the pot-shaped inner part 26 . The guiding bush 28 at the same time forms an abutment for the springs 34 , which place the magnet carrier 30 and the magnet 32 elastically under tension in an upwards direction in FIG. 1 in a position at rest.
A known torque limiter 36 is effectively disposed between the cap 16 and the screw-in plug 14 . When the locking gas cap is screwed onto the tank connection pipe, the rotational movement of the cap 16 is transferred by this torque limiter 36 to the screw-in plug 14 until a specified limiting torque is attained. This limiting torque is selected so that the screw-in plug 14 is then screwed firmly into the threaded insert 20 and closes off the tank connection pipe tightly. The torque limiter 36 is indicated in FIG. 1 merely by broken lines and is formed by springs, which are held at the cap 16 and engage a ring of notches surrounding the guiding bush 28 (see DE 196 10 471 C2). In the state shown in FIG. 1, the limiting torque has just been exceeded, so that the spring has been displaced from the associated notch.
At its upper end protruding into the handle 18 , the magnet carrier 30 has a ring of cams 38 , which are skewed in the peripheral direction and interact with the releasing devices 40 , formed in the handle 18 . When the limiting torque of the torque limiter is exceeded, the cap 16 turns relative to the screw-in plug 14 and, with that, also relative to the magnet carrier 30 . The releasing devices 40 therefore slide on the skewed cams 38 and force the magnet carrier 30 downward, against the force of the springs 34 , into the release position shown in FIG. 1 . In this position, the magnet 32 brings about the closing of the reed contacts of a magnetic switch 42 , which is disposed on the outside at the tank connection pipe 12 . In this manner, a signal is generated, which indicates the complete closing of the locking gas cap.
If the cap 16 is turned further, the releasing devices 40 slide from the cam 38 , and the magnet carrier 30 , under the action of the spring 34 , rebounds up once again, so that it assumes the position at rest, shown in FIG. 2 . In this position, the magnet is further removed from the solenoid 42 . If the magnetic switch 42 previously was closed, it remains closed because of the magnetic remanence in the closed state.
When the locking gas cap 10 is screwed out of the tank connection pipe 12 , the distance between the magnet 32 and the magnetic switch 42 becomes larger, so that the magnetic switch opens up. Since the torque limiter 36 can act only in one direction of rotation, a torque, unlimited in principle, can be transferred to the screw-in plug 14 as it is being screwed out.
Subsequently, if the locking gas cap is screwed back once again onto the tank connection pipe and has reached once again the position shown in FIG. 2, the magnetic switch 42 remains open, since the force of the magnet 32 alone is insufficient for bringing the reed contacts into the closed position. Only when the limiting torque is exceeded once again and, at the same time, the magnet carrier 30 is moved once more into the release position shown in FIG. 1, does the magnetic force become so large that the magnetic switch 42 is closed once again and then remains closed.
In a modified embodiment, it is also possible to form the torque limiter directly by the cams 38 and the releasing devices 40 . | An apparatus for monitoring the closed position of a locking gas cap ( 10 ) with a magnet ( 32 ) disposed at or in the locking gas cap and a solenoid ( 42 ) disposed at the tank connection pipe ( 12 ), the locking gas cap ( 10 ) having a torque limiter ( 36 ), and the magnet ( 32 ) being coupled with the torque limiter in such a manner, that it reaches a position, in which the solenoid ( 42 ) is triggered, only when the limiting torque is reached. | 1 |
BACKGROUND OF THE INVENTION
The present invention and improvement over co-pending applications, Ser. No. 654,299 filed Feb. 2, 1976 and Ser. No. 790,890 filed May 28, 1976 of the same inventor, provides further simplified and improved circuitry for selectively positioning the spark. The inventor further provides an improved ignition coil design having a short constant time dwell providing secondary voltage of 48 to 50 KV from a 12 volt system over a potential operating range of from idle to 12,000 RPM of an 8 cylinder engine while providing approximately 20 engine degrees of electronic spark advance.
Most ignition systems of the inductive type use a constant angle of rotation to provide dwell. As a result, at slow speeds, excessive current is used with resultant heating, while at speeds in excess of 2,500 RPM, there is insufficient dwell time to saturate the ignition coil core so that the secondary output voltage drops off appreciably.
U.S. Pat. Nos. 3,937,193 and 3,938,490 disclose methods providing limited periods of constant dwell time but still draw excessive current at low speeds and provide low secondary voltage at high speeds.
A multitude of other patents have issued which disclose various methods of providing solid state spark position circuitry but none of them use the alternating voltage generated directly by a magnetic pickup coil to provide a method of positioning the spark.
The Chrysler Corporation is currently building a spark positioning system based on U.S. Pat. Nos. 3,885,534 and 3,910,243 where the magnetic pickup signal is converted to a sawtooth pulse which is then utilized to provide spark advance. No attempt has been made to provide a constant dwell.
In accordance with the invention disclosed, a novel high-voltage distribution system is provided using a conventional diameter distributor cap of 37/8 inches for an 8 cylinder engine capable of distributing sparks in excess of 40 KV to the spark plugs while using full electronic spark advance. Delco Remy found it necessary to increase the diameter of the distributor cap on current distributors for 8 cylinder engines, to 53/8 inches when providing voltages of up to 35 KV with mechanical spark advance. In Applicant's co-pending application, Ser. No. 654,299, filed Feb. 2, 1976, a method of distributing spark voltages in excess of 40 KV is disclosed while providing full electronic advance using a novel rotor responsive to speed in a distributor cap diameter of 53/8 inches.
SUMMARY OF THE INVENTION
The present invention discloses a method and means for providing a constant dwell time for saturating the ignition coil core throughout the speed range of the engine while reducing the dwell time to as low as 0.35 milliseconds while still producing secondary voltages in the 48 to 50 KV range.
It is therefore an object of the invention to provide a novel, simple speed responsive spark advance circuitry.
Another object of this invention is to provide an improved construction of an ignition coil.
A further object of the invention is to provide a secondary voltage distribution system capable of distributing voltages in excess of 40 KV to spark plugs of an internal combustion engine without crossover firing and within the diameter of the conventional distributor caps of about 37/8 inches for an 8 cylinder engine.
A still further object of this invention is to provide a distributor cap for a V-8 engine having all spark plug cable outlets for the plugs on each side of the "V" on the corresponding side of the centerline of the distributor cap thus eliminating the necessity of the spark plug cables crossing over the cap to go to the proper spark plug.
A still further object of this invention is to increase the maximum operating speed of the ignition system while delivering full voltage output from the secondary winding of the ignition coil to the spark plugs of the internal combustion engine over speeds heretofore utilized.
Other objects, features and advantages of the present invention will become apparent from the subsequent description and appended claims taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
The present invention may be more readily described by reference to the accompanying drawings in which:
FIG. 1 is a block diagram of the system divided into functional sections.
FIG. 2 is a graphic illustration comprising parts 2A-2H showing the voltages and currents encountered over a 45-degree rotation of an 8-cylinder engine ignition system operating on a 12 volt supply at the outputs of the various functional sections shown in FIG. 1, wherein:
Line A shows the open circuit voltage developed by the pickup coil;
Line B shows the voltage of the pickup coil when connected to a pulse modifier and with the entire circuitry in operation while delivering a spark with zero spark advance;
Line C shows the voltage of the pickup coil when connected to the pulse modifier and with the entire circuitry in operation while delivering a spark with 10 degrees distributor spark advance or 20 degrees engine advance;
Line D shows the output of an amplifier when sensors or the basic speed spark advance provides a signal to the pulse modifier sufficient to give a spark advance of 10 distributor degrees or 20 engine degrees;
Line E shows the output of a timer with 20 degrees of engine advance;
Line F shows the current flow through the primary winding of an ignition coil, again with 20 degrees of engine spark advance;
Line G shows the secondary winding voltage as it breaks down a 1-inch needle gap;
Line H indicates the current read on an ammeter placed in the feed circuit to the entire system during the continuous operation of the system at 14.0 circuit volts and 2,000 engine RPM.
FIG. 3 is a schematic drawing illustrating the component forming the functional sections of the disclosed ignition system.
FIG. 4 is a graphic illustration showing the spark advance, as selected for a specific engine at both low and high engine vacuum.
FIG. 5 is a vertical cross-sectional view through the ignition coil of the ignition system disclosed;
FIG. 6 is a sectional view through the high voltage distribution system of the distributor of the invention;
FIG. 6A is a sectional view through the high voltage distribution system of the structure shown in FIG. 6 along the line 6A--6A.
FIG. 7 illustrates diagrammatically the current of the circuit in relationship to reluctor speeds of an 8-cylinder engine; and
FIG. 8 diagrammatically illustrates the coil voltage and currents immediately preceeding and subsequent to a spark in the ignition system disclosed.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawing by characters of reference, FIG. 1 discloses an improved electronic ignition system 20 of this invention comprising a reluctor 21 having as many teeth as cylinders in the associated engine, a pickup coil 22, a pulse modifier 23, a run amplifier 24, timer 25, switch 26, ignition coil 27, crank amplifier 28, interruptor 29, ignition switch 30, voltage regulator 31, spark position adjustor 32, sensors 33 and 34, diodes 35 and 36, distributor cap 38, distributor rotor 39, spark plugs 40 and 40' and battery 41.
The pick-up coil 22 is connected by its start and finish leads 42 and 43, respectively, to pulse modifier 23. Output 46 of pulse modifier 23 is connected by a conductor 47 to a first input 48 of run amplifier 24 and by a conductor 49 to a first input 51 of crank amplifier 28. Run amplifier 24 has its output 52 connected by a conductor 53 to a first input of timer 25. Crank amplifier 28 has its output 55 connected by conductor 56 to input 57 of interruptor 29. The outputs 58 and 59, respectively, of timer 25 and of interruptor 29 are connected to a common bus 63 which is connected by a first conductor 64 to a control 65 of switch 26 and by a second conductor 66 to a first input 67 of spark position adjustor 32.
The positive terminal 68 of battery 41 is connected by conductor 69 to ignition switch 30 and by a conductor 74 to the positive input terminal 75 of ignition coil 27.
The negative terminal 76 of ignition coil 27 is connected by conductor 77 to the positive terminal 78 of switch 26, and the negative terminal 79 of switch 26 is connected by conductor 81 to ground bus 82 which is connected to chassis ground 83. Also connected to ground bus 82 are the ground terminals 84, 85, 86, 87, 88, 89, and 91, respectively, of pulse modifier 23, crank amplifier 24, timer 25 and voltage regulator 31 and the negative terminal 92 of battery 41.
Ignition switch 30 has "CRANK", "RUN", and "OFF" positions with which the switch arm 93 makes connection from common terminal 73 to CRANK terminal 94, RUN terminal 95 and OFF terminal 96. RUN terminal 95 is connected to the anode of diode 35 and by a conductor 97 to inputs 98, 99 and 101, respectively, of spark position adjustor 32, run amplifier 24 and timer 25. Crank terminal 94 is connected by a conductor 102 to the anode of diode 36 and to a first input 103 of crank amplifier 28. The cathodes of diodes 35 and 36 are connected to a common point 104 which is connected by a conductor 105 to an input 106 of voltage regulator 31.
The output 107 of voltage regulator 31 is connected to inputs 109 and 111, respectively, of run amplifier 24 and crank amplifier 28.
Also shown in FIG. 1 is a cylinder 112 and piston 113 of an eight-cylinder internal combustion engine to which the ignition system 20 is connected.
System 20 operates in the CRANK (starting) mode when switch 30 is in the CRANK position and it operates in the RUN mode when switch 30 is in the RUN position. In the CRANK position, the crank amplifier 28 is enabled by battery voltage supplied through input 103 and conductor 102 while in the RUN position the spark position adjustor 32, run amplifier 24 and timer 25 are activated by battery voltage supplied from conductor 97.
Operation in the RUN mode
The distributor reluctor 21 is a gear-shaped wheel made of a magnetic material and it has a number of teeth 114 equal to the number of cylinders of the associated engine distributed symmetrically about its periphery. As the reluctor 21 is rotated by virtue of its mechanical coupling to the internal combustion engine, teeth 114, one at a time, pass core 115 of pickup coil 22. Through this action a cyclic variation of the flux linking coil 22 is effected and an alternating voltage is accordingly induced in coil 22 which is synchronized with the rotation of the engine.
The voltage output of pickup coil 22 is supplied by conductors 42 and 43 to pulse modifier 23 which modifies the alternating voltage pulses received displacing the pulses linearly relative to ground as a function of the speed of rotation of reluctor 21. Thus, as a reluctor tooth 114 approaches the core of the pickup coil 22, one end of coil 22 is positive relative to its other end, thus the output voltage applied to pulse modifier 23 reaches a positive level of X volts at some point in time prior to the time at which the tooth 114 reaches a position about six degrees ahead of direct alignment with core 115 of the pickup coil 22.
In the RUN mode, the output signal of pulse modifier 23 is delivered to run amplifier 24 which responds by delivering a rectangular output voltage pulse RAI. Run amplifier 24 turns on to initiate pulse RAI at the instant the output signal of pulse modifier 23 reaches the level of X volts and it turns off to terminate pulse RAI as the output signal of pulse modifier 23 falls below this level.
The output of run amplifier 24 is delivered as an input signal RAI to timer 25. Timer 25 produces a positive rectangular output voltage pulse TMI which is initiated at the leading edge of input signal RAI and is terminated at the end of a fixed time interval thereafter. With the proper operation of pulse modifier 23, in the absence of sensor signals, pulse TMI will be terminated at all engine speeds just as tooth 114 reaches the point about six degrees ahead of direct alignment with core 115 of pickup coil 22. This time relationship is achieved through the action of pulse modifier 23 in appropriately shifting its output voltage relative to ground as engine speed varies.
Pulse TMI from timer 25 is delivered to the control terminal 65 of switch 26 and causes switch 26 to be turned on during the constant time interval of pulse TMI. While switch 26 is turned on, current flows from the positive terminal 68 of the 12 V battery 41 through the primary winding of ignition coil 27 and through switch 26 to the negative terminal 92 of the battery. It should be recognized that the system can function on other voltages, such as 6, 18 and 24 volts with adjustments according in the circuit parameters.
The design of ignition coil 27 is such that its core reaches saturation during the period of time that switch 26 is turned on. When current in the primary winding is terminated, the flux in the core of coil 27 collapses rapidly, producing a high voltage in its secondary winding by virtue of the action of timer 25. As described earlier, the high secondary voltage pulse of coil 27 is always initiated in the absence of sensor signals about six degrees ahead of alignment between tooth 114 and the core of pickup coil 22, and consequently at a constant piston position independent of engine speed.
The high voltage pulse thus developed by coil 27 is distributed by the high voltage distributor cap 38 and rotor 39 to the spark plugs 40 and 40'.
Because the duration of pulse TMI developed by timer 25 is constant while its repetition rate is proportional to engine speed, the d-c or average value of the signal TMI will vary directly with engine speed. This relationship is utilized to produce a spark advance whereby the signal TMI is delivered via line 66 to spark position adjustor 32 which reacts by producing a voltage that is fed back to pulse modifier 23 via line 100. Voltage fed back to pulse modifier 23 causes an appropriate shift in the level of the output of pulse modifier 23 with respect to ground as required to produce the desired spark advance.
The basic speed responsive spark advance may be made responsive also to other signals related to engine performance, such as engine vacuum, temperature, rate, throttle position, acceleration rate, etc. For this purpose, the sensors 33 and 34 are provided, which are shown connected to spark position adjustor 32 by signal lines 16. The automatic adjustment of ignition timing relative to these and other parameters may be employed to optimize vehicle operation and to limit emissions in the engine exhaust.
Operating waveforms for the circuits described thus far are shown in FIG. 2. The waveforms correspond to forty-five degrees of rotation of reluctor 21 which covers the development of a single firing pulse in coil 22 as initiated by the movement of one of the teeth 114 past pickup coil 22. The waveforms of FIG. 2 are taken from laboratory tests of a complete system firing a one-inch needle gap operating at 1,000 distributor RPM under the control of the ignition system 20 of FIG. 1. FIG. 2A shows the open circuit voltage developed in pickup coil 22 as tooth 114 of reluctor 21 approaches and then moves on past the core of coil 22. FIG. 2B shows the voltage developed in pickup coil 22 when connected to pulse modifier 23 with the circuits of FIG. 1 in operation under conditions calling for zero spark advance. FIG. 2C shows the same signal but modified through the action of the spark position adjustor 32 feeding the pulse modifier 23 to produce 10 degrees of distributor spark advance or a 20 degree advance relative to engine rotation. FIG. 2D shows the output of run amplifier 24 under conditions producing 10 degrees of distributor spark advance and FIG. 2E shows the output of timer 25 under the same conditions. Current flow through the primary winding of ignition coil 27 is shown in FIG. 2F, and the voltage developed in the secondary winding of coil 27 is shown in FIG. 2G. Average current drawn by the circuit of FIG. 1 during operation at an engine speed of 2,000 RPM is shown in FIG. 2H.
The interrelationship of the waveforms of FIG. 2C through 2G is in conformance with the operation of the circuits of FIG. 1 as previously described. Thus, for example, the initiation of the output pulse of amplifier 24 as shown in FIG. 2D coincides with the point at which the pulse modifier 23 output voltage reaches X bolts, as shown in FIG. 2C. The signal produced by timer 25 is initiated at the same time and persists for a fixed time interval of approximately 0.042 milliseconds. The primary current of coil 27 as shown in FIG. 2F rises to a peak value during the interval of the timer signal. Upon the interruption of current flow through the primary winding of coil 27, the output pulse from its secondary coil is shown in FIG. 2G when firing a 1-inch needle gap.
When the system 20 is operating in the CRANK mode, the output of pulse modifier 23 is received by crank amplifier 28 at its input 51. Amplifier 28 responds by delivering a series of pulses at its output terminal 55 each time it is enabled at its input. The series of output pulses is delivered to switch 26 via conductor 64 to produce the desired series of sparks to plugs 40 and 40' for starting the engine.
Details of the circuits comprising the system 20 of FIG. 1 are shown in the circuit diagram of FIG. 3. Corresponding circuit blocks are identified by the same numerals in FIGS. 1 and 3.
The pulse modifier 23 comprises two series strings of diodes D4 and D5 and a capacitor C4. The series diodes D4 and D5 are all polarized in the same direction with the positive or anode end of string D4 connected to terminal W of coil 22 and the negative or cathode end of string D5 connected to terminal T of coil 22 so that when a voltage is induced in coil 22 the diode strings D4 and D5 will pass current when terminal W of coil 22 is positive with respect to its terminal T and they will block current flow during the opposite polarity of induced voltage. Terminal T of coil 22 and the cathode end of diode string D5 are connected to plate T of capacitor C4, and the opposite plate of capacitor C4 is connected to chassis ground 83. Also connected to the T plate of capacitor C4 is the line 100 which delivers the output signal of the spark position adjustor 32. The junction 117 between diode strings D4 and D5 is connected to chassis ground 83, and the output terminal 46 is connected to terminal W of diode string D4.
The serially connected diode strings D4 and D5 form a unidirectional voltage divider the resistance of which varies with the applied voltage. Furthermore, it has been found that in the absence of sensor signals and with the proper selection of the number and type of diodes D4 and D5 for a given design of coil 22 and with a proper value of the capacitor C4, the pulse modifier 23 output voltage at terminal 46, when connected to the common input terminal 51 of amplifiers 24 and 28 will reach a positive fixed value of "X" volts, a constant time interval in advance of the instant when a booth 114 of reluctor 21 reaches a position about 6 degrees prior to direct alignment with the core 115 of coil 22, in the absence of sensor signals, at all engine speeds. In a practical application of this circuit, the following parameters are used:
______________________________________pickup coil 22: 3,000 turns of #40 wirediode string D4: 5 silicon diodesdiode string D5: 3 silicon diodescapacitor C4: 10 microfarods.______________________________________
In the RUN mode of system 20, the output signal of pulse modifier 23 is delivered by conductors 49 and 47 to input 48 of run amplifier 24, amplifier 24 comprising a voltage comparator 118, with an output resistor R16, input resistors R17 and R20, divider resistors R18 and R19, and divider resistors R21 and R22 (as shown in crank amplifier 28). Comparator 118 is an integrated circuit having a supply pin 14, a ground pin 7, a non-inverting input pin 12, an inverting input pin 11, and an output pin 10. The comparator 118 produces a positive signal at its output pin 10 when pin 12 is positive with respect to pin 11 and it produces no signal at pin 10 when pin 11 is positive with respect to pin 12.
In run amplifier 24, the divider resistors R18 and R19 are serially connected between the positive five-volt supply line 109 and chassis ground 83. The common point between resistors R18 and R19 is connected through resistor R17 to inverting pin 11 of comparator 118. A fixed reference voltage is thus supplied to pin 11 at a level of approximately "X" volts. Conductor 47, which delivers the signal from pulse modifier 23, is connected to non-inverting input pin 12 through resistor R20 and to supply conductor 109 through resistor R21. Output pin 10 of comparator 118 is connected to run amplifier output 54 through resistor R16. Resistor R22, which is shown to be located inside crank amplifier 28, is connected between terminal 48 and ground 83 so that, together, resistors R21 and R22 form a divider network which biases pin 12 at a level which causes pin 12 to be negative with respect to the reference level established at pin 11 when there is no signal present on line 47 and the output pin 10 under this condition will be at ground potential. For all values of the input signal in excess of "X" volts appearing at terminal 48, the output pin 10 will deliver a positive signal approaching the five-volt supply voltage connected at pin 14. A square-wave output pulse 119 is thus produced at pin 10 in response to the irregular waveform 121 produced by coil 22 and pulse modifier 23.
Timer 25, which receives signal 119 from amplifier 24, includes a trigger stage, a timer circuit and an output stage.
The trigger stage comprises transisor T8, resistors R9 and R10 and capacitor C8. Resistors R9 and R10 are serially connected from the collector of transistor T8 to regulated voltage bus 109 with R10 connected directly to the collector, and capacitor C8 connected across resistor R10. The base of transistor T8 serves as the input 54 of timer 25 and is connected to output of amplifier 24.
The timer circuit comprises an integrated circuit (IC) timer 122, a timer network, R6 and C3, and a stabilizing capacitor C2. Timer 122 is a commonly used integrated circuit produced by several manufacturers, as a type 555 timer. Capacitor C2 is connected from pin 5 to ground, pin 1 is connected to ground, pins 4 and 8 are connected to supply conductor 97, resistor R6 is connected from supply conductor 97 to pins 6 and 7, and capacitor C3 is connected from pins 6 and 7 to ground. Pin 2 is the trigger input terminal and pin 3 is the output terminal. When connected in this manner, with resistor R6 and capacitors C2 and C3, timer 122 functions as a monostable multivibrator which is triggered by the leading edge of a negative pulse applied at terminal 2 and responds by delivering a positive pulse of fixed duration at output terminal 3. The duration of the positive pulse is determined by the time-constant (R6)(C3).
The output stage of timer 25 comprises a transistor T4, collector resistor R3, base resistor R5 and diode D4. Transistor T4 has its collector connected through resistor R3 to supply conductor 97, its emitter is connected to ground through resistor R4 and its base is connected through resistor R5 to pin 3 of timer 122.
In the operation of timer 25, the application of the square-wave positive pulse 119 to the base of transistor T8 renders transistor T8 conductive and its collector voltage falls abruptly to ground. Charging current flowing through resistor R9 and capacitor C8 produces a negative pulse 123 at the junction 124 between resistor R9 and capacitor C8. The negative pulse 123 is delivered to trigger pin 2 of timer 122 by a line 125 which is connected to pin 2 from junction 124. Responding to pulse 123, timer 122 produces a positive pulse at its output pin, the pulse driving transistor T4, which provided power amplification. The output of transistor T4 is developed as a positive pulse across emitter resistor R4 and is coupled through diode D4 to output terminal 58 of timer 25. The positive pulse delivered to terminal 58 is a square-wave pulse 126 which is utilized to drive switch 26.
Switch 26 is an NPN transistor TI. The base of transistor TI serves as the control terminal 65 of switch 26, the collector serves as the positive switch terminal 78, and the emitter, which is connected to ground, serves as the negative switch terminal 79. A by-pass diode D10 is connected across transistor TI, its cathode connected to the collector and its anode to the emitter. Diode D10 protects transistor TI against reverse current flow which may be developed through parasitic oscillations.
The ignition coil 27 comprises a primary winding 127, a secondary winding 128, a capacitor C9, a magnetic core 129 and a diode D5. Primary winding 127 is connected at one end to the positive switch terminal 78 and at the other end through conductors 74 and 69 to the positive terminal of battery 41. Capacitor C9 is connected directly across primary winding 127.
Switch 26 turns on during the pulse 126 to excite the primary winding 127 of coil 27. During the time that transistor TI is rendered conductive by pulse 126, current flows from the positive terminal of battery 41 through conductors 69 and 74, winding 127 and transistor TI to the negative terminal 92 of battery 41. During this time, the current builds up in winding 127 at an approximately constant rate from zero to peak value. The duration of the pulse 126 is held constant by timer 25. A relatively constant value of energy (1/2 LI 2 ) is thus stored in winding core combination 127, 129 each time the switch 26 is pulsed.
At the end of pulse 126, transistor TI turns off and the magnetic flux in core 129 collapses rapidly, inducing a high voltage pulse in secondary winding 128, which is coupled to distributor rotor 39 through diode D5 and conductor 131. Diode D5 is back-biased during the conduction of transistor TI, blocking current flow until the secondary voltage reverses with the turn-off of transistor TI. Capacitor C9 absorbs enery during the turn-off of transistor TI, thereby reducing the peak voltage developed across transistor TI. This permits the use of a less costly transistor for transistor TI.
Also operative during the RUN mode is the spark position adjustor 32, which comprises transistors T6 and T7, diode 11, diode string D7, zener diode Z1, capacitor C13, sensor resistors RS1, RS2, RS3, RS4, RS5 and RS6 and fixed resistors R31, R32, and R37. Diode string DD7 comprises two or more serially connected diodes. Sensor resistors RS1 and RS2 are serially connected from conductor 97 to the emitter of PNP transistor T7. Resistor R37 is connected between the emitter of transistor T7 and the collector of NPN transistor T6 and sensor resistor RS3 is connected between the base of transistor T7 and the collector of transistor T6. The emitter of transistor T6 is connected to chassis ground 83 and its base is connected through resistor R31 to the emitter of transistor T4 of timer 25. Zener diode Z1 and capacitor C13 are connected to the collector of transistor T7 to ground 83. Diode string D7 is connected between the collector of transistor T7 and terminal node N. Connected in parallel with string D7 are serially connected sensor, resistors RS4, RS5 and RS6.
Resistor RS6 is a potentiometer operated by engine vacuum. It has a movable arm or wiper 132 and a wound resistive element. The one end of resistor element is connected to one end of sensor resistor RS5 while the other end of the resistor element is connected through resistor R32 and diode D11 to ground 83. The wiper 132 is connected to node N.
The operation of spark adjustor 32 occurs as follows:
One function of spark position adjustor 32, i.e., the advancement of the spark with speed, is accomplished in response to the signal from timer 25. This signal is recieved at the base of transistor T6 and is supplied through resistor R31 from the emitter of transistor T4. Because transistor T4 of timer 25 is pulsed, and because the pulse rate is proportional to speed, the average value of the voltage developed across resistor R4 is directly proportional to engine speed. As this signal is coupled to the base of transistor T6, transistor T6 becomes increasingly conductive with engine speed. The increasing collector current drawn by transistor T6 is drawn primarily through sensor resistor RS3 from the base of transistor T7. As a consequence, transistor T7 also becomes increasingly conductive with engine speed and its increasing collector current flow through diode string D7 into capacitor C4. This increases the voltage across C4 and is added to the pulse induced in coil 22, and the sum of the capacitor voltage and the coil pulse reaches the level of "X" volts at an earlier time relative to the instantaneous engine position so that rum amplifier 24 is triggered earlier and the spark generated in ignition coil 27 is generated at a correspondingly earlier point in the cycle.
The spark advance function is programmed by the sensors RS1 through RS6 and by diode string D7. Resistor R32 and diode D11 as well as zener diode Z1 performs limiting functions. Because of the integrating effect of capacitor C13, the pulsating current supplied from the collector of transistor T7 produces a d-c level at the positive plate of capacitor C13. This d-c level rises with engine speed until it reaches the breakover voltage of zener diode Z1. The point at which this occurs corresponds to the maximum degree of spark advance, except for the additional controlling effects of the sensor RS1-RS6. Thus, for example, at a given level of voltage at the positive plate of capacitor C13, the total series resistance offered by sensor resistors RS4, RS5 and RS6 has an effect on the current delivered to capacitor C4. If their series resistance decreases, an increasing amount of current is shunted around diode string D7, the shunted current flowing from the collector of transistor T7 through sensor resistors RS4, RS5 and RS6 to line 100 and capacitor C4. As the resistance of any of these resistors decreases, the voltage on capacitor C4 increases and the spark is advanced accordingly until transistor T7 becomes unsaturated, i.e. until the drive to transistor T7 becomes the limiting factor. At this point, the sensor resistors RS1-RS2 come into play. A reduction in the resistance of any of these elements results in an increased availability of current from transistor T7. Thus, for example, as RS3 resistance decreases, the base drive to transistor T7 is increased. As the resistance of RS1 or RS2 decreases, the voltage at the emitter of transistor T7 tends to rise, again promoting increased base drive and increased collector current. In summary, a decrease in resistance of any of the sensor resistors RS1-RS7 produces increased charging current to capacitor C4.
Each of the sensor resistors RS1-RS6 may respond to a different operating parameter. The sensor resistor RS6, for example, is preferably controlled by engine vacuum, and sensor resistors RS4 and RS5 are controlled by engine temperature and intake air temperature, their resistance decreasing with temperature. At high engine vacuum, the wiper 132 is moved toward the junction of RS6 and RS5, thereby decreasing the resistance of RS6 and so advancing the spark. At low engine vacuum, the wiper 132 is moved toward the junction of RS6 and R32, thereby increasing the resistance of RS6 and delaying the spark until finally wiper 132 reaches the end of its travel at this point, node N is clamped to ground 83 through resistor R32 and diode D11. Because of the series resistance afforded by resistor R32, the current supplied to capacitor C4 is still responsive to engine speed, but the effect is appreciably reduced, and at higher speeds is limited to the extent necessary for the attainment of a maxium advance for any values of sensor resistors RS1, RS2 and RS3.
The port providing the vacuum which controls sensor resistor RS6 is located in the throat of the carburetor, just above the throttle blade. This renders the spark advance inoperative during idle and until the throttle is opened slightly.
Sensor resistors RS1-RS3 may be made responsive to any desired engine parameter, such as throttle position or rate of opening, torque, acceleration, etc.
The proper design of the spark position adjustor 32 and the associated sensor resistors RS1-RS6 permits the control of the spark position, as desired, one such typical relationship is shown in FIG. 4.
In the RUN mode of operation just described, the ignition switch 73 was set in the RUN position with switch arm 93 making contact with RUN terminal 95. Voltage from the positive plate of battery 41 is thus applied through conductors 69 and 72 to ignition switch 30 through arm 93 to terminal 95 and conductor 97. From conductor 97 voltage is supplied through diode D9 to voltage regulator 31 as well as to the various circuits which are operative during the RUN mode including the spark position adjustor 32, run amplifier 24 and timer 25. The voltage regulator 31 which has been energized by the voltage supplied through diode D9 delivers five volts at its output terminal 107 which is distributed by bus 109 to RUN amplifier 24 and crank amplifier 28. It will be noted, however, that crank amplifier 28 is disabled in the RUN position of switch 30 because no voltage is made available to the collector of transistor T5 through conductor 102. Furthermore, because interruptor 29 can only be energized by transistor T5, this circuit is also rendered inoperative during the RUN mode.
During the CRANK mode, arm 93 of switch 30 makes contace with CRANK terminal 94 to that battery voltage is supplied through conductor 102 and diode D8 to voltage regulator 31 but is blocked from conductor 97 by diode D9. Battery voltage is also supplied by conductor 102 to the collector or transistor T5 in CRANK amplifier 28 so that CRANK amplifier 28 is enabled. Because no voltage is delivered to conductor 97, the spark position adjustor 32 and the timer 25 are rendered inoperative.
The CRANK amplifier 28 comprises a voltage comparator 136, NPN transistor T5 and resistors R11, R12, R21 (as shown in Run Amplifier 24) R22, and R25 through R30. Comparator 136 is identical to comparator 118 of Run Amplifier 24. Its inverting input terminal 11' is connected through resistor R25 to the common point between divider resistors R26 and R26 which are serially connected between bus 109 and ground 83 to provide a reference voltage at their common terminals. The non-inverting input terminal 12' of comparator 136 is connected through resistor R28 to input terminal 51 of CRANK amplifier 28. Resistors R21 and R22 form a voltage divider which is common with Run Amplifier 24. Supply terminal 14 is connected to bus 109 and ground terminal 7 is connected to chassis ground 83. Transistor T5 has its base connected through resistor R11 to output terminal 10' of comparator 136, its emitter is connected to ground 83 through resistor R29 and its collector is tied to the common point between serially connected resistors R12 and R30, which form a divider between ground 83 and battery voltage supplied at conductor 102. The emitter of transistor T5 is also connected to output terminal 55 of CRANK amplifier 28.
Interruptor 29 comprises PNP transistors T13 and T14, resistors R33-R36 and capacitor C10-C12 connected as a free-running multivibrator. The emitters of transistors T13 and T14 are connected together and also to terminal 55. The base of transistor T13 is connected to ground through resistor R35 and the base of transistor R14 is connected to ground through resistor R36, the collectors of transistors T13 and T14 are connected to ground through resistors R33 and R34, respectively, and capacitor C10 is connected in parallel with resistor R33. Capacitor C11 is connected from the base of transistor T13 to the collector of transistor T14 and capacitor C12 is connected from the base of transistor T14 to the collector of transistor T13.
Operation of CRANK amplifier 28 and interruptor 29 occurs as follows:
As the signal from pulse modifier 23 exceeds the level of "X" volts, the non-inverting input terminal 12' of comparator 136 becomes positive with respect to inverting input terminal 11', which is referenced to "X" volts by divider resistors R26 and R27. As terminal 12' exceeds "X" volts output, terminal 10' switches abruptly from ground potential to a value slightly below +5 volts and supplies base drive to transistor T5, causing its emitter voltage to rise and thereby exciting interruptor 29 by raising the emitters of transistors T13 and T14 to approximately four volts above ground. The base of transistor T14 is held more solidly to ground than that of transistor T13 by virtue of the series connection of capacitors C10 and C12 from the base of transistor T14 to ground. For this reason transistor T14 turns on first, and as it does its collector voltage rises coupling a positive voltage to the base of transistor T13, which holds transistor T13 in a non-conductive condition. Then as capacitor C11 charges toward the collector voltage of transistor T14, the base voltage of transistor T13 declines until transistor T13 turns abruptly on. The abrupt turn-on of transistor T13 produces a sharp rise in its collector voltage which is coupled through capacitor C12 to the base of transistor T14 to turn transistor T14 off. The interruptor 29 is thus seen to function in the manner of the conventional multivibrator in which the two transistors conduct and turn off alternately with a square wave produced at the collector of each transistor. The conduction periods are determined by the time constants (R33)(C12) and (R34)(C11), which are set relatively low so that each time a pulse is supplied at terminal 55 by CRANK amplifier 28, the interruptor 29 produces a series of square-wave pulses at its output terminal 59. The two time constants are set for a pulse width of approximately 0.85 milliseconds and a separation of 0.3 milliseconds. The series of pulses from terminal 59 are supplied to switch 26, causing it to respond by alternately energizing ignition coil 27 thus producing a series of sparks over about six degrees of rotation of reluctor 21. The longer pulse time produced by interruptor 29 provides sufficient time to permit saturation of the ignition coil 27, core 129 when the battery 41 voltage is reduced during cranking.
The physical construction of the ignition coil 27 is shown in FIG. 5. The ignition coil 27 comprises a bottle-shaped insulating housing 141, the magnetic core 129, primary winding 127, secondary winding 128, a bell-shaped insulating spacer 142, a cup-shaped magnetic shield 143, feed-through terminals 144 and 145, diode D5, capacitor C9, switch 26 and base cap 146. Extending upward from the base of a cylindrical depression 137 in the end of the neck 138 at the top of housing 141 is a high-voltage pin 139.
The bell-shaped insulating spacer 142 has a central depression 147, which serves as a support for the lower end of the core 129. The base of the spacer 142 rests atop the inverted cup-shaped shield 143, which fits inside the open lower end of housing 141. The base cap 146 closes the lower end of shield 143, forming a closed compartment 148 inside shield 143 for housing the switch 26 and the capacitor C9.
External access to the compartment 148 is by means of the terminals 144 and 145, which penetrate the side walls of shield 143, and access from compartment 148 to the primary winding 27 enclosed by housing 141 is through two insulating grommets 149 and 150, which are captured in two holes located in the flat top surface of shield 143.
The core 129 is preferably constructed of about 33 strips of high quality magnetic iron, 3/16 inches wide, 0.014 inches thick, and long enough to project one inch or more beyond the ends of the secondary winding 128. Alternatively, core 129 may be of ferrite material, as produced by Indiana General and others. In this case, a larger diameter will be required because of the reduced achievable flux density.
An insulating tube 151, which slips over the core 129, serves as the coil form over which the secondary winding 128 is wound.
Secondary winding 128 is wound in a manner which reduces the amount of energy stored in the layer-to-layer capacitance during the collapse of the field in the core 129. Each layer is wound from left to right or vice versa, the finish conductor being returned from right to left in a one-turn spiral for the start of the next layer. A layer of insulation is placed over each winding layer and another over the spiral return. This method of winding produces a constant layer-to-layer voltage of E volts between the entire length of the layers, whereas the conventional manner of winding in which alternate layers are wound from right to left and from left to right produces a linear voltage variation from zero to 2E volts between the length of the layers. Assuming the same value of layer-to-layer capacitance for the two winding methods, the method employed in this invention reduces the energy stored in the capacitance to sixty-seven percent of the energy stored in the conventionally wound coil. The secondary winding has a total of approximately 25,000 turns. The start of the secondary winding is connected to the core 129. The finish of the secondary winding and the start of the primary winding are connected to terminal 144, to which connection is made from the positive terminal of battery 41 by conductors 74 and 69. The top end of the core 129 makes electrical contact with the cathode of diode D5, which couples the voltage from secondary winding 128 to pin 139. As shown in FIG. 1, pin 139 is connected by conductor 131 to the rotor 39 of the distributor cap 38.
Primary winding 127 is wound over the top of secondary winding 128. The conductor is a flat strip material having a width panel, approximately, to the length of the secondary winding 128. Each turn is wound over the preceding turn with a strip of insulation wound in to insulate each turn from the next. In the preferred implementation, there are about 56 turns in primary winding 127 for a 12-volt supply, wound as described with one turn per layer. The d-c resistance of the winding 127 is very low (approximately 0.025 ohms) so that the rise of current in the primary winding is limited almost exclusively by the inductance of primary winding 127.
The entire housing 141 and the compartment 148 are sealed at all the joints and filled with a high quality dielectric oil.
In a coil of this type, the capacitive energy stored in the inter-layer capacitance is many times greater in the secondary winding 128 than in the primary winding 127. For this reason and also because of the inherent leakage inductance between the primary and secondary windings, the rise of secondary voltage following the opening of switch 26 will be delayed appreciably relative to the rise of the primary voltage. The connection of capacitor C9 across primary winding 127 delays the rise of the primary voltage so that it tends to coincide with the rise of the secondary voltage. As described in co-pending application Ser. No. 654,299 of Feb. 2, 1976, the discharge of current from this capacitor back through the primary winding also tends to reset the core permitting a higher level of energy storage and recovery.
The reduction in secondary winding capacitance by virtue of the winding method employed also permits a higher peak energy to be developed at the output terminal of the coil while the increased primary capacitance achieved through the strip winding advantageously increase primary winding capacitance.
These benefits result in a reduction in the "dwell" time, i.e. the period of primary current flow which is required to achieve a given level of secondary voltage. In the implementation of the invention, the "dwell" time was reduced by virtue of this construction of 0.35 milliseconds, as compared with a "dwell" time of 0.56 milliseconds, as shown in application Ser. No. 654,299. The benefit of the reduced "dwell" time is a capability for producing high-voltage discharges at a given voltage level at a considerably higher firing rate with less energy input required.
A more detailed description of the operation of ignition coil 27 and switch 26 is now possible with reference to the construction features just described and also with reference to the operating waveforms of FIG. 8.
The waveforms of FIG. 8 show currents and voltages in primary and secondary windings 127 and 128 and in capacitor C9 for the period immediately following the turn-off of switch 26.
At the instant just prior to the opening of switch 26 the current in primary winding 127 has reached a level of 24 amperes, having risen at an approximately constant rate from zero at the point of turn-on of switch 26. This period of energy storage corresponds to the "dwell" period referenced earlier and its duration is approximately 0.40 milliseconds.
At zero time in FIG. 8, transistor T1 of switch 26 is turned off and the current in primary winding begins to decay as shown in FIG. 8(A). Because transistor T1 is turned off, the primary current seeks another path and finds it in capacitor C9, where capacitor current is seen to rise in approximately 0.01 milliseconds to more than 20 amperes FIG. 8(C). The 0.01 milliseconds accounts for the time required by transistor T1 to turn off.
At 0.01 milliseconds and continuing to 0.07 milliseconds the collapse of the flux in core 129 accompanies an oscillatory energy exchange between primary winding 127, capacitor C9 and the interlayer capacitance of secondary winding 128. The sinusoidal contours of the current and voltage waveforms during this period is evidence of the high-Q (low resistance) achieved in the design of coil 27. At 0.04 milliseconds the circulating current through capacitor C9 and primary winding 127 has reversed its polarity returning the magnetization in core 129 to zero. At 0.07 milliseconds the voltage across secondary winding and its inter-layer capacitance has reached 42,000 volts when breakdown occurs at the needle gap simulating the firing of a spark plug.
The buildup of primary current following the initiation of the discharge at 0.07 milliseconds is a reflection of secondary discharge current in which energy is transferred by transformer action from capacitor C9 and primary turn-to-turn capacitance to the secondary winding 128 and eventually to the discharge arc. A damped oscillation follows until all stored energy is dissipated in the arc. The capacitive energy transferred from capacitor C9 to the arc helps to extend the period of the arc discharge, assisting materially in the ignition of the leaner and colder mixtures present in the cylinder under certain conditions.
It will be appreciated that except for the primary winding capacitance and the additional capacitance provided by capacitor C9, the primary voltage would rise to a higher level during the turn-off of transistor T1. The total primary capacity has also been shown to provide supplementary energy to the discharge arc.
Polarization of the secondary winding 128 relative to that of the primary winding 127 is such that diode D5 is reverse-biased and hence blocks secondary current flow during the "ON" time of switch 26, otherwise referenced as the "dwell" time. The polarity of secondary voltage is reversed at time zero in FIG. 8 when switch 26 turns off.
Because the collapse of the flux in core 129 occurs at a much higher rate than the rate at which it was established, both primary and secondary voltages are considerably higher following the opening of the switch 26 than prior to the opening of the switch. Secondary voltage following the opening of the switch may exceed 50 kilovolts and primary voltage can go to 130 volts should larger dwell time be used.
The constant energy level of the discharge achieved over the speed range of the engine is evidenced by the linear rise of current drawn from the battery as a function of speed. This relationship is illustrated in FIG. 7, which shows average current as a function of reluctor RPM. Approximate corresponding road speeds are also indicated for an eight-cylinder engine.
The construction of a high-voltage distributor designed for use with the present invention is shown in FIGS. 6 and 6A.
The distributor 159, as shown in FIGS. 6 and 6A, comprises a stationary cap 38, a stationary spider assembly 161 and a revolving commutator cup or rotor 39.
The cap 38 is in the form of an inverted cup and is molded from a rugged insulating material. Extending upwardly from the center of the flat top surface is a connector pin 163 protected by an insulating busing 164. Surrounding pin 163 and evenly spaced in a circle near the outer edge of the top surface of cap 38 are eight additional connector pins 165, 165' and associated bushings 166, 166'. The pin 163 serves as a connecting means for introducing the spark from ignition coil 27 and the surrounding pins 165, 165' which are spaced at 45-degree intervals serving as the connecting means for the spark plugs of an eight-cylinder engine.
Alternate pins are labeled 165 and 165' to distinguish two groups of four pins, the first group including the four pins 165 are spaced at 90 degree intervals about the circumference of cap 160 and the other four pins 165' are spaced half way between the first four pins.
Extending downwardly from each of the pins 165 is a conductor 167 which is molded inside the insulating body of the cap 38. The four conductors 167 extend to a common vertical level where they terminate in four rounded conductor ends 168, which penetrate and protrude slightly beyond the inner cylindrical surface of cap 38. The four conductor ends 168 are aligned radially with the four pins 165 from which the four conductors 167 extend.
In the same manner, four conductors 167' extend downwardly from the alternate pins 165' and terminate in conductor ends 168' at a second vertical level spaced below the level at which the ends 168 were located. The conductor ends 168' are aligned radially with the pins 165'.
The spider assembly 161, which is integral with the cap 38, comprises a central conductive shaft 171 on which are mounted an upper spider 172 and a lower spider 173. Each of the spiders 172 and 173 has four coplanar arms extending outwardly from a central hub 175 equally spaced ninety degrees apart. The top of the shaft 171 is molded into the center of the top wall of cap 38 and it extends vertically downwardly therefrom. The pin 163, which is integral with the shaft 171, extends vertically upwardly from its top end. The spiders 172 and 173 are rigidly attached to shaft 171, the shaft passing through the hubs 175 so that the axis of the shaft 171 is perpendicular to the planes of the spiders 172 and 173. Spider 172 is coplanar with conductor ends 168 and spider 173 is coplanar with conductor ends 168'. Spider 173 is angularly displaced forty-five degrees from spider 172.
Commutator cup of rotor 39 comprises a cylindrical cup 176 fixed to the top of a shaft 177, the shaft 177 being secured perpendicularly to the center of the bottom surface of the cup 176. The cup 176 extends upwardly inside cap 38 and is coaxial with cap 38 and with the shaft 171 of spider assembly 161. The vertical walls of cup 176 pass between the interior cylindircal surfaces of cap 38 and the ends of the arms of the spiders 172 and 173. Carried in the vertical walls of the cup 176 are two conductive inserts, 178 and 179. The inserts 178 nd 179 are rectangular bars oriented horizontally. They are mounted opposite each other at an angular displacement of 180 degrees. Insert 178 is mounted coplanar with spider 172 and insert 179 is mounted coplanar with spider 173. Also fixed and rigidly indexed to the shaft but not shown in FIG. 6 is the reluctor 21 of FIG. 1.
The angular relationships of the spiders 172 and 173, the conductor ends 168 and 168' and the inserts 178 and 179 are best shown in FIG. 6A. As indicated earlier, the positions and alignment of the spiders 172 and 173 with the conductor ends 168 and 168' are fixed as shown while the intervening cup 176 is rotated by the engine in the direction indicated by the arrow 181. The arms of the spiders 172 and 173 extend almost to the inner surface of the cup 176, there being just sufficient clearance allowed to permit the passage of the inserts 178 and 179 past the ends of the arms 174. Minimal clearance is also provided between the outer surfaces of the inserts 178 and 179 and the conductor ends 168 and 168'.
The cup 176 is rotated by means of shaft 177 at one-half engine speed carrying the inserts 178 and 179 through the gaps separating the tips of the spider arms from the conductor ends 168 and 168'. It will be noted that for each forty-five degree increment of rotation, one of the inserts 168 or 169 will pass between a conductor end and the tip of an arm. If this occurs simultaneously with the generation of a voltage pulse by ignition coil 27, the pulse will pass from shaft 171 through the aligned spider arm, insert 178 or 179 and conductor end, 168 or 168' jumping the gaps and thence through the embedded conductor 167 or 167' to the connected pin 165 or 165' and through the spark plug cable to the plug. Because it is necessary to advance or delay the spark relative to rotational position, the inserts 178 and 179 must have sufficient circumferential length to insure that a portion of its length is aligned with the conductor end for any adjustment of the spark position. This consideration dictates a circumferential length of about twenty degrees.
Considering now the sequential operation of the distributor 159 with reference again to FIG. 6A, it will be noted that the individual conductor ends 168 and 168' are identified by the Roman numerals I-VIII followed by one of the digits, 1-8. By this designation the firing order and the spark plug locations are shown, the Roman numerals indicating the firing order and the Arabic numeral the plug location. For this purpose, the odd numbers 1, 3, 5 and 7 identify the plug positions from front to rear on one side of a V-8 engine and the even numbers 2, 4, 6, 8 identify the plug positions from front to rear on the other side of the engine. Also shown in FIG. 6A is the center line of the engine, indicating the orientation of the distributor 159 relative to the two sides of the engine.
The firing order, as indicated by the Roman numerals, may be verified by examination of FIG. 6A. In the instant shown, the upper insert 178 is just leaving alignment between upper spider 172 arm and upper conductor end 168 which is identified by Roman numeral IV. As cup 176 continues to rotate in the direction of arrow 181, alignment will next occur between lower spider 173 arm and lower conductor end 168' with lower insert 179 and is identified by the Roman numeral V, etc. The spark plug identifiers 1-8 have been assigned to provide an order 3-6-5-7-2-1-8-4, or when this sequence is rearranged to start with number 1, we get 1-8-4-3-6-5-7-2, which is the firing order used by many V8 engines. It will be noted that when this is done the even plug location numbers all lie on one side of the engine centerline and the odd numbered plug numbers locations on the opposite side. This is advantageous since it permits the dressing of the spark plug cables without having to cross over the top of the distributor 159.
Should the direction of rotation of cup 176 be reversed, as is the case with some V8 engines. this same arrangement can be accomplished by merely re-orienting the distributor 159 relative to the engine centerline by 45 degrees.
The primary advantage of the distributor assembly 159, as shown in FIGS. 6 and 6A, is that its special construction provides ample clearance for the high voltage sparks generated by the disclosed ignition system 20 while requiring no increase in overall diameter relative to a conventional distributor. This advantage has been achieved by separating alternate gaps into the two vertical layers associated with the two spiders 172 and 173. In this connection, the vertical distance between the two levels must be adequate to prevent a high voltage breakdown between a conductor end 168 at one level and a conductor end 168' in the other level. The same kinds of considerations also dictate the other dimensions of the distributor 159. The design of a working model in accordance with the invention yields a distributor capable of handling in excess of 40 kilovolts which is no larger dimensionally than a conventional distributor which is desinged for a lower voltage.
The same orientation of spark plug cables, relative to the engine V's , as described above, may be accomplished by replacing the cup 176 and spiders 172 and 173 with a somewhat conventional rotor except having two arms 180° apart, one lining up with the lower conductor ends 168' and the other lining up with the upper conductor ends 168. Thus when lower secondary voltages are acceptable, this construction will be less costly.
A solid-state ignition system and a novel distributor design have thus been provided in accordance with the stated objects of the invention. Although but a single embodiment of the invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. | A solid state inductive ignition system for igniting the mixture in the cylinders of an associated engine with a spark of up to 48 to 50 KV occurring at the most desirable position of the pistons for maximum mileage and power with a minimum of undesirable exhaust emissions. Exceptionally wide spark plug gaps are used to aid in igniting extra lean mixtures. The invention includes a novel high voltage spark distribution system utilizing, if desired, a conventional diameter distribution cap while providing sufficient clearance between adjacent spark plug cable outlets to prevent crossfire. Multiple sparks are provided while cranking to insure the ignition of overly rich or lean mixtures and a constant dwell of extremely short duration is used when running to saturate the core of the ignition coil. | 5 |
BACKGROUND
1. Technical Field
The present invention generally relates to a construction structure, more specifically, relates to a technology and a method of a modular construction structure, which can be applied in fields of architecture, furniture, and toy; meanwhile, the scope of the invention is not limited to the above fields, it is obvious to those skilled in the art that the invention can also be applied in other fields.
2. Description of Related Art
At present, most of modular systems are applied in the field of toy. The modular systems used in the toys are simply assembled and the structures of the objects assembled by the modular systems are unstable, resulting in the easy collapse thereof when being shaken. Additionally, the modular systems are not securely lockable and are not expandable. Nowadays, a few modular systems are designed to securely lockable, however, limited to the structures of these modular systems, the object assembled by the modular system has a single shape and is unstable, preventing the modular systems to be applied in other fields, such as the fields of architecture and furniture.
In the main technology of constructing a building, frame structures composed of steel reinforced concrete and bricks as well as walls constructed by concrete are used for dividing the space of the building. However, using the steel reinforced concrete, bricks, and walls to construct the building consumes a lot of resources and requires for heavy-duty machinery. Also, after the building is pulled down, a lot of construction waste will be produced. Furthermore, since the shape and the space of the building are constructed according to designed drawings, it is very difficult to alter the constructed building. Besides, the kind of building does not have movability and expandability.
Except the buildings built by steel reinforced concrete structure, most of the present modular buildings are like stacked containers. By designing a kind of connecting member or some locking portion, one of the containers is located above another container. However, this only divides and stacks the building simply, making the building look like a number of blocks stacked together from outside. Large mechanical machines are required in the constructing process of the building, and the shapes of the blocks of the building and the space of the building cannot be changed, which prevents the building from having expandability. At the same time, this kind of building is constructed by stacking a number of other units of same type, which greatly affects the movability of the building. Additionally, this kind of building cannot be disassembled into part, thus, the raw material of the building cannot be in common use with other buildings.
Another type of modular building uses steel bars and panels which can be assembled together and disassembled from each other to form the frames and the walls of the building. The steel bars and panels are connected to each other via various connecting members to form a house composed of frames, walls, and floors, for example, the complete-board house which is decoration-free and assembled rapidly described in the Chinese patent application CN200410028042.2, which is published on Jan. 18, 2006. This kind of modular building allows the space of the building to be expanded and the material to be recycled. Houses can be assembled rapidly by industrializedly producing the components in large number to satisfy housing demand from people. However, limited to the structures of these components, the shape and the space of the building assembled by these components are similar to the structure of a honeycomb, lacking of humanization and selection diversity in design. Also, due to limitations on universalnesses of these components, these components can be only used for constructing buildings of one or several particular shapes and of special functions.
It is known that light steel, especially cold-formed thin-walled light steel structure systems, are commonly used for constructing modular houses in European countries and America. The cold-formed thin-walled light steel structure system technology is mature in Australia and the principle thereof is similar to that of the technology of using modular panels to assemble the complete-board house which is decoration-free and is assembled rapidly as mentioned above, that is, using steel bars and panels which can be assembled together and disassembled from each other to form the frames and the walls of the building, and then connecting the steel bars and panels through connecting members to form the house composed of frames, walls, and floor. However, the main characteristic of using light steel to construct the building is that all the structural components of the building are pre-designed in the computer. These structural components required for forming the building such as frames of walls, floor beams, and roof trusses then are directly produced by the technology of CAD, by the control of light steel constructing and designing software, and by precise processing from intellectual processing apparatus. The manufacturing processes of these structural components are carried out by professional apparatus controlled by computer software. The other floor systems are constructed by using waterproof glass tile, waterproof coiled material, heat preservation material cotton, stringers, suspended fireproof gypsum board. The whole process is the similar to the industrialized production of automobile elements. The advantages of the modular building include small precision error of the structural components within half-millimeter which cannot be reached when being manufactured manually and mature producing processes of these structural components. The shortcomings of the modular building lie in: the manufacturing cost is high; the standard and programmed inner arrangement and supporting facility designs prevent people from handing the building freely because the building has been divided by the structure of the steel; additionally, galvanized steel is used in this kind of building for improving the corrosion resistance of the steel, which allows the main steel structure of the building to have the greatest corrosion resistance and to endure for 50 years; furthermore, a lot of new materials are required in construction of this kind of building in which the light steel is cooperated with heat preservation material and heat insulation material; besides, light new material is generally used for meeting the requirement of convenient construction. It is noted that the constructing process of this kind of building is carried out according to pre-designed constructing images, in this way, the so called “modular building” means assembling the pre-manufactured material like assembling building blocks, but not really means constructing the building using modular components. The structural component does not have universalness and lack of the expandability thereof in space and in function. Since the building is completely constructed according to pre-designed drawings, therefore, the construction of the building does not have the flexibility of the building blocks.
SUMMARY
The object of the present invention is to provide a modular construction system, structural principle of components and assembling method of the modular construction system. Specifically, the object of the invention is using a series of exchangeable components which can be assembled together in different ways to form various kinds of objects which have different functions and are composed of planes and standing column shaped structures.
A modular construction system, and components and assembling method thereof, including a series of components, the components includes “ ” shaped components, “ ” shaped components, “ ” shaped component, “ ” shaped pin components, and a number of kinds of fish-bone shaped components; the fish-bone shaped components are formed according to the shapes of Chinese character “ ”, Chinese character “ ”, Chinese character “ ”, Chinese character “ ”, Chinese character “ ”; except the “ ” shaped pin components, the series of components are formed by combining a number of identical cubes which are arranged according to a thickness of one cube and according to the shapes of the above Chinese characters; convexes and concaves formed in each component is cube shaped, therefore, the series of components are capable of being locked to each other to allow the convexes to respectively engage with the concaves, thereby forming a number of stable objects composed of planes and standing column shaped structures; the series of components can be considered as universal elements of disassembled planes and standing columns; different kinds of components are assembled through the engagements between the convexes and concaves thereof; a hole is defined in each cube of the series of components to allow the “ ” shaped pin component to pass therethrough and to be locked therein; by integrating locking functions of “ ” shaped pin components and the “ ” shaped components into the components themselves, the stable planes and standing column structures can be formed when locking the components together; the material of the component is of high tensile strength.
The essence of the present invention is locking a series of regularly shaped modular components to each other to assemble objects of different functions which are composed of planes and standing column shaped structures. The series of components have the same geometric structure principles, and each component is composed of a number of cubes arranged according to a thickness of one cube and the shapes of the above Chinese characters, wherein:
one kind of the fish-bone shaped components is composed of nineteen identical cubes arranged together according to the thickness of one cube in the order that the shape of the Chinese character “ ” is located above and the shape of Chinese character “ ” is located below (as component 1 shown in FIG. 1 ), and each cube of the fish-bone shaped component defines a hole into which the “ ” shaped pin component is inserted (as component 1 and component 2 shown in FIG. 24 );
one kind of the fish-bone shaped components is composed of nineteen identical cubes arranged together according to the thickness of one cube in the order that the shape of the Chinese character “ ” is located above and the shape of Chinese character “ ” is located below (as component 1 shown in FIG. 1 ), and each cube 20 of the fish-bone shaped component defines a hole 22 into which the “ ” shaped pin component is inserted (as component 1 and component 2 shown in FIG. 24 );
one kind of the fish-bone shaped components is composed of sixteen identical cubes arranged according to the thickness of one cube in the order that the shapes of the Chinese characters “ ” are respectively located above and below (as component 3 shown in FIG. 1 ), and each cube of the component defines a hole into which the “ ” shaped pin component is inserted (as component 3 and component 4 shown in FIG. 24 );
one kind of the fish-bone shaped components is composed of eighteen identical cubes arranged according to the thickness of one cube in the order that the shape of the Chinese character “ ” is located above and the shape of the Chinese character “ ” is located below (as component 4 shown in FIG. 1 ), and each cube of the component defines a hole into which the “ ” shaped pin component is inserted.
one kind of the fish-bone shaped components is composed of sixteen identical cubes arranged according to the thickness of one cube in the order that the shape of the Chinese character “ ” is located above and the shape of the Chinese character “ ” is located below (as component 5 shown in FIG. 1 ), and each cube of the component defines a hole into which the “ ” shaped pin component is inserted;
one kind of the “ ” shaped component is composed of sixteen identical cubes arranged according to the thickness of one cube and according to the shape of the Chinese character “ ” (as component 6 shown FIG. 1 );
one kind of the “ ” shaped component is composed of five identical cubes arranged according to the thickness of one cube and according to the shape of the Chinese character “ ” (as component 7 shown FIG. 1 );
one kind of the “ ” shaped component is composed of nine identical cubes arranged according to the thickness of one cube and according to the shape of the Chinese character “ ” (as component 8 shown in FIG. 1 );
one kind of the fish-bone shaped components is composed of fifteen identical cubes arranged according to the thickness of one cube in the order that the shapes of the Chinese characters “ ” are respectively located above, in the middle, and below (as component 9 shown in FIG. 13 ), and each cube of the component defines a hole into which the “ ” shaped pin component is inserted;
one kind of the fish-bone shaped components is composed of twenty-one identical cubes arranged according to the thickness of one cube in the order that the shapes of the Chinese characters “ ” are respectively located above, in the middle, and located below (as component 10 shown in FIG. 13 ), and each cube of the component defines a hole into which the “ ” shaped pin component is inserted;
the “ ” shaped component is composed of seventeen identical cubes arranged according to the thickness of one cube and according to the shape of the Chinese character “ ” (as component 11 shown in FIG. 13 );
the “ ” shaped component is composed of seven identical cubes arranged according to the thickness of one cube and according to the shape of the Chinese character “ ” (as component 12 shown in FIG. 13 );
one kind of the fish-bone shaped components is composed of seventeen cubes arranged according to the thickness of one cube in the order that the shape of the Chinese character “ ” is located above and the shape of the Chinese character “ ” is located below (as component 13 shown in FIG. 13 ), and each cube of the component defines a hole in which the “ ” shaped pin component is inserted;
one kind of the fish-hone shaped components is composed of fifteen identical cubes arranged according to the thickness of one cube in the order that the shape of the Chinese character “ ” is located above and the shape of the Chinese character “ ” is located below (as component 14 shown in FIG. 13 ); this kind of fish-bone shaped component can be considered as a component formed by cutting two middle cubes of another component (as component 13 shown in FIG. 13 );
one kind of the “ ” shaped component is composed of eight identical cubes arranged according to the thickness of one cube and according to the shape of the Chinese character “ ” (as component 15 shown FIG. 13 );
one kind of the fish-hone shaped components is composed of fourteen identical cubes arranged according to the thickness of one cube in the order that the shapes of the Chinese characters “ ” are respectively located above and below (as component 16 shown in FIG. 13 ), and each cube of the component defines a hole into which the “ ” shaped pin component is inserted (as component 7 shown FIG. 24 );
one kind of the fish-hone shaped components is composed of fourteen identical cubes arranged according to the thickness of one cube in the order that the shapes of the Chinese characters “ ” are respectively located above and below (as component 16 shown in FIG. 13 ), and each cube of the component defines a hole into which the “ ” shaped pin component passing is inserted (as component 7 shown FIG. 24 );
one kind of the fish-bone shaped component is composed of twelve identical cubes arranged according to the thickness of one cube in the order that the shape of the Chinese characters “ ” are respectively locating above, in the middle, and below (as component 18 shown in FIG. 13 ); the fish-bone shaped component can be considered as a component formed by cutting three middle cubes of another component (as component 9 shown in FIG. 13 );
the “ ” shaped component is composed of eleven cubes arranged according to a thickness of one cube and according to the shape of the Chinese character “ ” (as component 3 shown FIG. 13 );
one kind of the fish-bone shaped components is composed of thirty-three identical cubes arranged according to the thickness of one cube in the order that the shapes of the Chinese characters “ ” are respectively located above, in the middle, and located below (as component 5 shown in FIG. 23 ), and each cube of the component defines a hole into which the “ ” shaped pin component is inserted;
one kind of the fish-bone shaped components is composed of twenty-three identical cubes arranged according to the thickness of one cube in the order that the shape of the Chinese character “ ” is located above and the shape of the Chinese character “ ” is located below (as component 6 shown in FIG. 23 ); each cube of the component defines a hole into which the “ ” shaped pin component is inserted;
one kind of the components is composed of seventeen identical cubes arranged according to the thickness of one cube and according to the shape of the Chinese character “ ” with one cube protruding from one lateral side thereof (as component 8 shown in FIG. 23 );
one kind of the components is composed of twelve identical cubes arranged according to the thickness of one cube and according to the shape of the Chinese character “ ” with one cube protruding from one lateral side thereof (as component 8 shown in FIG. 23 );
one kind of the fish-bone shaped components is composed of ten identical cubes arranged according to the thickness of one cube in the order that the shapes of the Chinese characters “ ” are respectively located above and below (as component 8 shown in FIG. 23 ), and each cube defines a hole into which the “ ” shaped pin component is inserted (as component 6 shown in FIG. 24 );
the “ ” shaped pin components include long pins and short pins, the short pins (as component 8 shown in FIG. 24 ) are used for being inserted into enclosed holes (as the holes shown in FIG. 24 ), and the long pins (as component 9 shown in FIG. 24 ) are used for being inserted into through holes (as the holes shown in FIG. 24 ).
The principle of the present invention is that: since convexes and the concaves formed in each component are cube shaped, therefore, the series of components are capable of being locked to each other by using different locking and assembling methods to allow the convexes to respectively engage with the concaves; according to one main locking and assembling method of the standing column, three pairs of above fish-bone shaped components are used, wherein two pairs of the components each of which has identical front and rear sides are locked to the other pair of the components each of which has identical left and right sides from two ends to form a standing column having a cross section composed of 3*3 cubes, the “ ” shaped component is used for surrounding and locking the standing column, and the “ ” shaped component is inserted into the holes defined in the locked components of the standing column to support and prevent the “ ” shaped component from sliding downwards, thereby finishing the locking and assembling of the components of the standing column; an extending portion of the standing column is assembled according to the same assembling method; and according to the principle, various standing columns of different shapes can be assembled by using different fish-bone shaped components.
According to the same principle, one main locking and assembling method of the plane is using two pairs of the above fish-bone shaped components, wherein one pair of the components each of which has identical front and rear sides is locked to the other pair of the components each of which has identical left and right sides to form a standing column having a cross section composed of 3*3 cubes, the “ ” shaped component is used for surrounding and locking the standing column, the standing column then is placed horizontally and considered to be an assembly of a cross beam; an extending portion of the cross beam is assembled according to the same assembling method, the “ ” shaped components is locked to an upper side of the cross beam, thereby finishing the manufacture of the single cross beam; a number of cross beams are assembled according to the same assembling method, and the cross beams are placed in parallel to form a suspended plane structure; according to the principle, when constructing a building, floors and stairs of the building can be assembled according to the assembling method.
According to the same principle, one main locking and assembling method of a wall is locking a pair of components each of which has identical front and rear sides to another pair of components each of which has identical upper and lower sides to form a standing column having a cross section composed of 3*3 cubes; the standing column is then placed horizontally and extended according to the same assembling method; after every three pairs of the components are locked together, concave spaces in shapes of the Chinese character “ ” or “ ” are defined in the upper/lower side or the front/rear side of the three pairs of locked components; three of the standing columns assembled according to the same method are placed horizontally as a top standing column, a middle standing column, and a lower standing column parallel to each other; a pair of fish-hone shaped components each of which has identical front and rear sides is locked to the concave spaces defined in the top standing column and the middle standing column placed in parallel; another pair of fish-bone components each of which has identical front and rear sides is locked to the concave spaces defined in the middle standing column and the lower standing column placed in parallel, thereby locking the top standing column, the middle standing column, and the lower standing column together; an extending portion of the wall can be assembled according to the same principle and the assembling method.
According to the same principle, one main locking and assembling method of the standing column is using two pairs of fish-bone components, wherein one pair of the fish-bone shaped components each of which has identical front and rear sides is locked to the other pair of the fish-bone shaped components to form the sanding column having a cross section composed of 3*3 cubes; the “ ” shaped pin component is inserted into the holes defined in the locked components to lock the two pairs of fish-bone shaped components; an extending portion of the standing column is assembled by the same assembling method; according to the principle, various standing columns of different shapes are assembled by using different fish-bone shaped components.
According to the same principle, one main locking and assembling method of the standing column is using two pairs of fish-bone shaped components with holes, wherein the cubes located in each corner of one pair of the fish-bone shaped components each of which has identical upper and lower sides define enclosed holes perpendicular to the plane of the components, the cubes located in main part of the corresponding pair of fish-hone shaped components define through holes perpendicular to the planes of the corresponding components and parallel to the main part of the corresponding components; the cubes of the pair of fish-bone shaped components each of which has identical left and right sides, except the cubes located in the main part thereof, define through holes perpendicular to the planes of the corresponding components and parallel to the main part of the corresponding components; a “ ” shaped short pin component is inserted into the holes defined in the main part of the pair of components each of which has identical left and right sides, thus, the short pin component is enclosed inside the components when the pair of components each of which has identical upper and lower sides is locked to the pair of components each of which has identical left and right sides; a “ ” shaped long pin component is inserted into the holes defined in the pair of components each of which has identical left and right sides; through the assembling sequence, the short pin component can prevent the pair of components each of which has identical left and right sides from moving forth and back inside the components, and the long pin component can prevent the pair of components each of which has identical upper and lower sides from moving upwards and downwards; an extending portion of the standing column is assembled according to the same assembling method; concave spaces in shapes of Chinese character “ ” or “ ” are defined in the standing column when locking the extending portion of the standing column; a number of the standing columns are assembled according to the same method, the standing columns are placed in parallel to each other and adjacent to each other, a fish-bone shaped component containing the shape of the Chinese character “ ” or “ ” shaped is locked to the concave spaces to lock adjacent standing columns together; in the above kinds of fish-bone shaped component, the cubes of the fish-bone shaped component containing the shape of the Chinese character “ ”, except the cubes located in the main part of the component, define through holes parallel to the plane and the main part of the corresponding component; a “ ” shaped long pin component is inserted into the adjacent and associating holes defined in the pair of components each of which has identical left and right sides to prevent associating components from moving downwards; and an extending portion of the plane can be assembled according to the same assembling method.
In specific working process of the present invention, a number of objects having same structures which are composed of planes and standing column shaped structures can be manufactured by assembling the modular components. The present invention can be applied in the fields of housing, public building and facility, furniture, and toy. Since the components of the present invention are connected together via locking structures formed thereon, thus, the components needs to be made of material of high tensile strength which can be selected from the group consisting of metal, wooden, synthetic wooden, and plastic.
Compared to the present technology from the aspect of simple assembly, when constructing buildings including houses, the series of building components of the present invention can be assembled together by using the characteristics themselves without using reinforced steel, concrete or other connecting members. Due to the simplification of the material forming the building, a number of constructing processes can be saved compared to the present technology, for example, the processes of soldering reinforced steel, pouring concrete, and drying concrete. Similarly, in the application of the present invention in the field of furniture, there is no requirement for any connecting members made of icon such as screws and nuts and no requirement for other material such as glue.
Compared to the present technology from the aspects of environmental protection and resource recycling, on one hand, when applying the present invention in the field of building, the components of the present invention can be locked together by the their own structures to form stable structures, therefore, walls, columns, beams, and frames can be built without using intermediate material such as reinforced steel, concrete, and sand and stone, which greatly reduces the reliance on of the building on the reinforced steel, concrete, and sand and stone; on the other hand, since the series of components can be assembled in different was to form different shapes, the flexible structures gives life to the components; as the assembly of different genes can form organs and organizations having different functions, several identical kinds of components can be arranged in different ways to form constructions, which can be houses (as shown in FIG. 12 ), columns of streetlights, telegraph poles, walls, roadblocks (as shown in FIG. 3 ), bus stations (as shown in FIG. 4 ), and yachts docks. Properties of the components allow the components to be recycled after the constructions are disassembled. Generally, furniture is often abandoned as a waste after playing its part fully or being overused and damaged. When applying the present invention in the field of furniture, the components can be re-assembled to form another piece of furniture according to requirements, such as the chair shown in FIG. 1 , the table shown in FIG. 2 , and the chairs manufactured by components with holes shown in FIG. 24 . In this way, the second-hand objects can be recycled, which greatly reduces the environmental destruction from the wasted furniture and plays an important role in environmental protection and resources recycling.
Compared to the present technology from the aspect of universalness, in the application of the present invention in the field of architecture, the components of the present invention work as ordinary bricks and can be assembled to form buildings of different shapes without using intermediate connecting material, while the ordinary bricks are required to be used with reinforced steel and concrete to construct the buildings. The components of the present invention can be considered universal elements of these buildings which can be assembled in different ways to form objects composed of planes and columns, such as houses, pedestrian bridges, streetlights, walls, bus stations, and so on. When being applied in the field of furniture, the components can be used in different ways by taking advantage of their universalnesses, thereby allowing people to manufacture suitable furniture such as chairs, tables, bookcases, shoeboxes, and so on according to specific requirements.
Compared to the present technology from the aspect of spatial expandability, in the application of the present invention in the field of architecture, buildings constructed by the components of the present invention have good expandability. For example, to a house, people can transform the space of the house; to a pedestrian bridge, people can widen and lengthen the bridge or adding a canopy to the bridge easily. When being applied in the field of furniture, furniture formed by assembling the components of the present invention also has good expandability. For example, to a chair, people can change the size, the height and the structure of the chair according to requirements without using products manufactured according to industrialized standards in the past.
Compared to the present technology from the aspects of manufacturing and maintaining costs, in the application of the present invention in the field of architecture, the producing cost and time are greatly saved and the constructing mode of the buildings are changed, allowing the buildings to be constructed without reinforced steel, concrete, and sands to reduce cost of raw material. During the constructions of the buildings, a number of unnecessary processes can be omitted to breakthrough restrictions in time and space, heavy-duty machinery can also be omitted, and the construction can be carried out all day to assemble the components without making much noise, which breakthroughs restrictions on constructing time; meanwhile, assemblies of large components can be finished in factory departments and then transported to the constructing site to be further assembled, which breakthroughs restrictions on space. Additionally, the building can be easily maintained by changing damaged components. By the reduction in raw material, reduction in constructing processes, reductions in constructing facilities, easy maintenance, and open space and time, people can assemble suitable houses according to requirements by industrially producing the components of the present invention in large number.
Compared to the present technology from the aspect of anti-seismic performance, in the application of the present invention in the field of architecture, when building houses, the components of the present invention are locked together and are connected to each other end-to-end. In this way, the building can be considered as a knitted entirety, and the building can be prevented from being cracked due to the damage of some component and the stabilities of the other components can be prevented from being influenced by the damaged component. Also, stress of the walls and columns of the constructed building are evenly distributed to resolve strong shakes. Thus, the houses built according to the present invention can protect lives and safeties of property in earthquake.
DESCRIPTION OF DRAWINGS
Many aspects of the embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily dawns to scale, the emphasis instead being placed upon clearly illustrating the principles of the embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
FIG. 1 is a schematic view of a chair, a piece of furniture manufactured by a modular construction system and components of the present invention;
FIG. 2 is a schematic view of a table, a piece of furniture manufactured by the modular construction system and the components of the present invention;
FIG. 3 is a schematic view of a highway roadblock manufactured by the modular construction system and the components of the present invention;
FIG. 4 is a schematic view of a bus station built by the modular construction system and the components of the present invention;
FIG. 5 is a schematic view of a pedestrian bridge built by the modular construction system and the components thereof of the present invention;
FIG. 6 is a schematic view of a portion A, supporting columns of a stair of the pedestrian bridge shown in FIG. 5 ;
FIG. 7 is a schematic view of a portion B, supporting columns of a main body of the pedestrian bridge shown in FIG. 5 ;
FIG. 8 is a schematic view of a portion C, supporting columns of a middle portion of the pedestrian bridge shown in FIG. 5 ;
FIG. 9 is a schematic view of a portion D, the stair of the pedestrian bridge shown in FIG. 5 ;
FIG. 10 is a schematic view of a portion E, a transshipping platform between the stairs of the pedestrian bridge shown in FIG. 5 ;
FIG. 11 is a schematic view of a portion F, a bridge deck of the pedestrian bridge shown in FIG. 5 ;
FIG. 12 is a schematic view of house unit built by the modular construction system and the components thereof of the invention;
FIG. 13 is a schematic view of a portion A, a balcony of the house shown in FIG. 12 ;
FIG. 14 is a schematic view of a portion B, a wall with a large window of the house shown in FIG. 12 ;
FIG. 15 is a schematic view of a portion C, a wall with a small window of the house shown in FIG. 12 ;
FIG. 16 is a schematic view of a portion D, an enclosed wall of the house shown in FIG. 12 ;
FIG. 17 is a schematic view of a portion E, another wall with a large window of the house shown in FIG. 12 ;
FIG. 18 is a schematic view of a portion F, a wall with a door of the house shown in FIG. 12 ;
FIG. 19 is a schematic view of a portion G, another wall with a door of the house shown in FIG. 12 ;
FIG. 20 is a schematic view of a portion H, a transshipping plate of a stair of the house shown in FIG. 12 ;
FIG. 21 is a schematic view of a portion I, the stair of the house shown in FIG. 12 ;
FIG. 22 is a schematic view of a portion J, an aisle of the stair of the house shown in FIG. 12 ;
FIG. 23 is a schematic view of another wall and another floor built by the modular construction system and the components of the invention;
FIG. 24 is a schematic view of a chair, a piece of furniture manufactured by the modular construction system and the components with holes of the invention.
DETAILED DESCRIPTION
The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment is this disclosure are not necessarily to the same embodiment, and such references mean at least one.
In specific applications of the present invention, since the components with holes and the components without holes respectively have advantages and shortcomings, suitable components can be selected or the components with holes or without holes can be mixed and matched according to practical requirements. When manufacturing objects via components with holes, fish-bone shaped components can be simplified to more simple shapes in situations where “ ” shaped components are not required, allowing planes and standing columns assembled by the components to have smoother lines and have outlines more approachable to that of practical objects in real life. However, since the process of assembling the components to form graphic objects is an one-way process, in the assembled planes, one component is locked to another component, like zipping up a zipper. When disassembling one part from the object, all the components in the zipper must be disassembled, reducing the function of simple assembly and simple disassembly of this kind of plane structure. Giving the advantages and shortcomings and the difficulty of assembly and disassembly of this kind of plane structure to overall consideration, it is desirable to use this kind of plane structure in field of furniture. In order to express the principle of the modular construction system sufficiently, in the embodiment, the components without holes are described as the main component, and the components are made of material of high tensile strength such as metal, wooden or synthetic wooden, and plastic. Since plastic not only has good chemical stability, corrosion resistance, electrical insulation, heat insulation, shock absorption capability, noise reduction effect, and good elasticity, but also can be easily pasted to other material such as metal, glass, and wooden, and can be manufactured easily, therefore, plastic is used as the material of the component in the embodiment. The component in the embodiment is made of plastic, with a bottom side of thereof being removed and the main body thereof being sallow and configured with reinforcing arms, which guarantees the light weight of the component and the easy assembly of the components. The specific assembling method in each embodiment can be referred to numerals shown in each drawing which is labeled along a line and used for representing a corresponding component shown in the drawing.
Referring to FIG. 1 , which is a schematic view showing a chair manufactured by the modular construction system and the components thereof, in accordance with an embodiment of applying the present invention in the field of furniture. The modular components forming the chair include components 1 , 2 , 3 , 4 , 5 , 6 , 7 , and 8 . The eight kinds of components are locked to each other in some order to form standing columns and planes of the chair. The assembling method of columns of the leg and the back of the chair is: using three pairs of fish-bone shaped components, two pairs of the fish-bone shaped component each of which has identical front and rear sides are locked to the other pair of the fish-bone shaped components each of which has identical left and right sides to form a column 30 having a cross section composed of 3*3 cubes, after that, a “ ” shaped component is used for surrounding and locking the column, a “ ” shaped component is inserted into holes defined by the locked components of the column to support the “ ” shaped component and further prevent the “ ” shaped component from sliding downwards, thereby finishing the locking and assembling of the assembly. An extending portion of the standing column can be assembled according to the same method. When disassembling the standing column, the “ ” shaped component is taken out from the standing column and the “ ” shaped component is slided to loosen other fish-bone shaped components. It is noted that the embodiment provides one way of locking the components to form a stable structure of the standing column and the effect thereof. The thickness of each of the series of components is 1 millimeter, correspondingly, the chair has a total height of 100 millimeters and a seat height of 44 millimeters.
Referring to FIG. 2 , which is a schematic view showing a table manufactured by the modular construction system and the components thereof, in accordance with an embodiment of applying the invention in the field of furniture. The components forming the table include components 1 , 2 , 3 , 4 , 5 , 7 , and 8 . The eight kinds of components are locked to each other in some order to form standing columns and planes of the table. The assembling method of the legs of the table is modified and improved based on the structure of the standing column of the chair in the embodiment shown in FIG. 1 , in which pairs of fish-bone shaped components 4 are used for locking two standing columns to form a standing columns having more stable structure and increased bearing capacity. The assembling method of a top surface of the table is: using two pairs of fish-bone shaped components, one pair of the fish-bone shaped components each of which has identical front and rear sides is locked to the other pair of the fish-bone shaped component each of which has identical left and right sides to form a standing column 30 having a cross section composed of 3*3 cubes; after that, the “ ” shaped component is used for surrounding and locking the standing column; the column than is placed horizontally and is considered as an assembly of a cross beam of the table; an extending portion of the cross beam is assembled in the same way; a “ ” shaped component is then locked onto the upper side of the cross beam, thereby finishing the assembly of the single cross beam. A number of the cross beams are assembled in the same way. The cross beams are placed parallel to each other form a suspended panel structure. Under a middle portion of the table, components 4 and 5 are used for forming a locking portion by using locking position preserved in the cross beam of a top surface of the table. The structure of the locking portion is the same as the structures of two ends of the top surface of the table, and the locking portion is perpendicular and locked to the adjacent cross beam of the top surface of the table. In the embodiment, the leg of the table can be reinforced according to requirements and the top surface of the table can be lengthened and widened according to requirements, which extends the application of the present invention. The thickness of each component of the series of components is one millimeter, correspondingly, the table has a height of 39 millimeters, a width of 70 millimeters, and a length of 109 millimeters.
Referring to FIG. 3 , which is a schematic view showing a roadblock manufactured by the modular construction system and the components thereof, in accordance with an embodiment of applying the present invention in the field of public facility. The modular components forming the roadblock include components 1 , 2 , and 3 . The three kinds of components are locked to each other in some order to form the roadblock. Through the embodiment, the roadblock can be manufactured by simply assembling the three kinds of components 1 , 2 , and 3 , which sufficiently shows the practicality and convenient assembly of the series of components. The thickness of each component of the series of components is 5 millimeters, correspondingly, the roadblock has a height of 90 millimeters and a total length of 925 millimeters.
Referring to FIG. 4 , which is a schematic view showing a frame of a bus station manufactured by the modular construction system and the components thereof, in accordance with an embodiment of applying the present invention in the field of public facility. The modular components forming the bus station include component 1 , 2 , 3 , 4 , 5 , 6 , 7 , and 8 . The eight kinds of components are locked to each other in some order to form columns and cross beams of the bus station. The assemblies of the columns and cross beams of the bus station are the similar to the assemblies of the columns and cross beams in the embodiments shown in FIGS. 1 and 2 . In practical application, component forming a base of the bus station are fixingly embedded underground to prevent the bus station from swaying sideways. From the embodiments, it can be concluded that using the eight kinds of components having the same structures as the structures of the eight kinds of components of the chair shown in FIG. 1 and the table shown in FIG. 2 , the components can be applied in the field of furniture when being manufactured in small sizes and applied in the field of public facility or architecture when being manufactured in large sizes. In the embodiment, the thickness of each component of the series of components is 5 millimeters, correspondingly, the bus station has a height of 360 millimeters, a width of 235 millimeters, and a length of 1125 millimeters.
Referring to FIG. 5 , which is a schematic view showing a pedestrian bridge manufactured by the modular construction system and the components thereof, in accordance with an embodiment of applying the present invention in the field of civic building. In the embodiment, main parts of the pedestrian bridge include parts A, B, C, D, E, and Components forming the six parts of are the same as the components 1 , 2 , 3 , 4 , 5 , 6 , 7 , and 8 used in FIG. 1 , FIG. 2 , and FIG. 4 . The specific structure of each above part can be referred to supporting columns of a stair of the pedestrian bridge shown in FIG. 6 , supporting columns of a main body of the pedestrian bridge shown in FIG. 7 , supporting columns of a middle portion of the pedestrian bridge shown in FIG. 8 , the stair of the pedestrian bridge shown in FIG. 9 , a transshipping platform between the stairs of the pedestrian bridge shown in FIG. 10 , and a top surface of the pedestrian bridge shown in FIG. 11 . The embodiment further shows universalness and practicality of the series of components. The thickness of each component of the series of components is 5 millimeters, correspondingly, the pedestrian bridge shown in FIG. 5 has a top surface of 535 millimeters tall, stairs of 255 millimeters wide, guardrails of 105 millimeters tall, and a bridge body of 2350 millimeters long.
Referring to FIG. 9 , which is a schematic view showing a part of the stair of the pedestrian bridge shown in FIG. 5 . Compared to other parts of the pedestrian bridge, another three kinds of components are used in the stair for forming inclined surfaces. These three kinds of components 9 , 10 , and 11 are geometric objects specifically designed for forming the inclined surfaces which allows bicycles to pass the pedestrian bridge. When being assembled, the concave defined in component 11 presses the “ ” shaped component 7 thereunder, and components 9 and 10 are locked onto the “ ” shaped component 7 to prevent the “ ” shaped component 7 from being slidable. From the schematic view of the structures of the stairs of the pedestrian bridge, it can be concluded the stair with inclined surfaces can be disassembled to planes and columns by the components 1 , 2 , 3 , 4 , 5 , 6 , 7 , and 8 , showing that the principle of the present invention is locking a series of modular components of different shape together to form the planes and columns of different kinds of objects of different functions.
Referring to FIG. 12 , which is a schematic view showing the structure of a single floor of a house built by the modular construction system and the components thereof, in accordance with an embodiment of applying the present invention in the field of architecture. The main structures of the house include the following 10 parts: A, B, C, D, F, F, G, H, I, and J. In the embodiment, the first floor of the built house can be considered as an unit. Since four walls and columns of a balcony and a stair of the house unit are provided with preserved components for being locked to corresponding portions of an upper storey, therefore, when building the second floor, the third floor, the fourth floor, and higher floors, it only requires repeatedly manufacturing the housing unit having the same structure as that of the first floor. The structure of each part of the housing unit can be referred to the balcony shown in FIG. 13 , a wall having a large window shown in FIG. 14 , a complete wall shown in FIG. 16 , another wall with a large window shown in FIG. 17 , a wall with a door shown in FIG. 18 , another wall with a door shown in FIG. 19 , a transshipping platform of the stair shown in FIG. 20 , a stair shown in FIG. 21 , and an aisle of the stair shown FIG. 22 . The thickness of each component in the embodiment is 5 millimeters, correspondingly, the single-floor house shown in FIG. 12 has a height of 300 millimeters and each wall of the house has a thickness of 15 millimeters.
Referring to FIGS. 13 to 22 , compared to the components used for manufacturing the pedestrian bridge, ten more kinds of components, such as components 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , and 18 shown in FIG. 13 , are used in the structures shown from FIGS. 13 to 22 . In the above components, the fish-bone shaped components 9 and 10 are used for stabilizing the wall of the house, the locking and assembling method of the wall is: locking one pair of component each of which has identical front and rear sides to another pair of component each of which has identical upper and lower sides to form a standing column 30 having a cross section composed of 3*3 cubes; the column then is placed horizontally to be extended according to the same method. After every three pairs of the components are locked together, concave spaces shaped as the Chinese character “ ” or “ ” are defined in upper/lower side or front/rear side of the three pairs of locked components. Three of the standing columns assembled according to the same method are placed horizontally as a top standing column, a middle standing column, and a lower standing column parallel to each other; a pair of fish-bone shaped components each of which has identical front and rear sides is locked to the concave spaces defined in the top standing column and the middle standing column placed in parallel; another pair of fish-bone components each of which has identical front and rear sides is locked to the concave spaces defined in the middle standing column and the lower standing column placed in parallel, thereby locking the top standing column, the middle standing column, and the lower standing column together. An extending portion of the wall can be assembled according to the same principle and method. Additionally, components 11 , 12 , 13 , 14 , 15 , 16 , 17 , and 18 are located in the connecting portion between the upper floor and the lower floor or located in opening positions corresponding to the door or the window in the wall. Components 9 , 10 , 13 , and 14 are used for locking the connecting portions, and components 11 , 12 , 15 , 16 , 17 , and 18 are used for filling the wall or the door and the openings located between the window and the wall. The numbers of components 11 , 12 , 13 , 14 , 15 , 16 , 17 , and 18 used in the embodiment are respectively low, and the components 11 , 12 , 14 , 16 , 17 and 18 can be manufactured by cutting components 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , and 10 . Thus, the main components used for manufacturing the house are still components 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , and 10 , among which most of the components are the same components used for manufacturing the pedestrian bridge shown in FIG. 5 .
Referring to the model of the wall and the floor surface shown in FIG. 23 , in the embodiment, another series of components of similar shapes, referring to the components 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , and 10 shown in FIG. 23 , are used for manufacturing the house. The house manufactured by the series of components has a similar structure to that of the house in the above embodiment. It can be told from the drawing that shapes of the wall, floor beam, and floor of the house manufactured in the embodiment are respectively different from the shapes of the wall, the floor beam, and the floor of the house in the embodiment shown in FIG. 12 . However, the locking way and principle of the structure of the house in the embodiment are the same as those of the house in the above embodiment shown in FIG. 12 . This series of components can be used for manufacturing houses with thickening walls. With the thickness of each component designed to be 5 millimeters, the thickness of the wall shown in FIG. 23 can reach 25 millimeters. From the embodiment, under the teaching of the idea of the invention and the embodiments of the invention, those skilled in the art are capable of immaterially modifying the embodiments according to what is disclosed in the invention, principles, and common senses, for example, partly changing the shapes of the components, changing the way that the components are locked to each other, and so on. As the structure and the components shown in the embodiment shown in FIG. 23 , modified embodiments of the same function and the same effect or embodiments similar to the above embodiments are within the scope of the invention.
Referring to FIG. 24 , which is a schematic view showing a chair manufactured by the modular construction system and the components, in accordance with an embodiment of applying the present invention in the field of furniture. The components forming the chair include components 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , and 9 . Components 1 to 7 are configured with holes and are locked to each other in some order with the “ ” shaped pin components 8 and 9 inserted thereinto to form columns and planes of the chair. Dotted lines shown in FIG. 24 are referred to short pin component 8 which is enclosed inside when being locked to other components and referred to the positions of the short pin component. In the embodiment, the thickness of each component of the series of components is 1 millimeter, correspondingly, the chair has a total height of 101 millimeters and a seating height of 40 millimeters. In practical application of the invention, more components configured with holes can be used for manufacturing objects in the field of furniture to allow the objects to have aesthetic figures. At the same time, from the embodiment, under the teaching of the idea of the invention and the embodiments of the invention, those skilled in the art are capable of immaterially modifying the embodiments according to what is disclosed in the invention, principles, and common senses, for example, partly changing the shapes of the components, changing the arrangements and directions of the holes, and so on, to form planes and columns. Modified embodiments having the same functions or effects as those of the above embodiment or embodiments similar to the above embodiment are within the scope of the invention.
Even though information and the advantages of the present embodiments have been set forth in the foregoing description, together with details of the mechanisms and functions of the present embodiments, the disclosure is illustrative only; and that changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the present embodiments to the full extend indicated by the broad general meaning of the terms in which the appended claims are expressed. | A modular construction system is provided, wherein the components ( 1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 ) thereof includes Chinese character shaped components and a number of fish-bone shaped components. The fish-bone shaped components are formed according to the shapes of multiple Chinese characters. Except the “ ” shaped pin components, the components ( 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 ) are formed by assembling multiple identical cubes arranged according to the thickness of one cube and the shapes of the above Chinese characters. Since the concaves and convexes of the components are cube shaped, the components ( 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 ) are locked to each other through the concaves and convexes between the components to assemble objects with stable structure composed of planes and standing column shaped structures. The components ( 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 ) can be considered as universal parts after the planes and upright columns are dissembled. An assembling method of the modular construction system is also provided. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of our U.S. application Ser. No. 617,428, filed Sept. 29, 1975, now abandoned.
BACKGROUND
This invention relates to amusement apparatus such as is found in amusement parks. In particular it relates to coin-operated apparatus for use by two persons for practicing the old sport of arm wrestling. Such apparatus comprises a suitable table, elbow cups to fix the players' elbow positions, fixed handles for the free hand of each player, and automatic scoring indicator devices and the like.
Our prior U.S. Pat. No. 3,649,010 shows one form of an arm-wrestling apparatus with elbow cups and automatic scoring means. When one player forces the other's arm down to a point that signifies a score or win, an electric contact actuates a suitable indicator. U.S. Pat. No. 3,735,983 to J. L. Ortiz shows another apparatus for such scoring which provides touch pads that actuate electrical contacts. Another showing of apparatus of this class is in U.S. Pat. No. 3,467,376.
BRIEF SUMMARY
This invention provides improved amusement and scoring apparatus for arm-wrestling which includes a pair of depressible touch pads mounted on the table top or the like being used for an arm-wrestling contest or game. The game is also called wrist-wrestling. Two depressible pads are located at opposite sides of the fixed elbow positions for engagement and depression by a losing contestant's arm or wrist. The pads actuate switch means to operate signal lights and the like.
In one embodiment of the invention, depression of a touch pad moves a pointer across a scale to indicate how far a pad has been depressed short of a complete "win". Frictional linkage or pivot means make the pointer stay at the point it has been pushed to. The scale is calibrated in suitable game points. At the bottom of the available travel of the pad, contacts may actuate, as before, suitable light signals, buzzers, or the like, to signal a win.
A coin-operated apparatus of the invention has lockout means to prevent its use when no coin has been fed into the coin acceptor. One such lockout means comprises depressible elbow rests which move freely downward unless they are locked in the "up" position necessary for play. The coin mechanism actuates a locking device to hold the elbow pads up.
An alternative coin-operated means employs a blocking element or bar in the middle of the table which a mechanism raises up to interfere with play. After a coin has been inserted, the mechanism lowers it down to the table top, out of the way.
A fixed handle is preferably provided for each player's free hand, to provide standardized playing conditions. Each handle may be provided with a suitable push-button switch or grip switch. When both players are in proper position, they each signal "ready" by pressing a handle switch, and a "READY" indicator lamp lights.
DETAILED DESCRIPTION
In the drawings:
FIG. 1 is a perspective view of an apparatus of the invention;
FIG. 2 is a section on line 2--2 of FIG. 1;
FIG. 3 is a section on line 3--3 of FIG. 2;
FIG. 4 is a side elevation of a modification;
FIG. 5 is a perspective view of a modified touch pad for actuating scoring devices;
FIG. 6 is a section on line 6--6 of FIG. 5;
FIG. 7 is a perspective of another modified touch pad;
FIG. 8 is a perspective view of a coin-operated apparatus having depressible lockable elbow rests;
FIG. 9 is a section on line 9--9 of FIG. 8;
FIG. 10 is a perspective detail of a locking mechanism;
FIG. 11 is a side detail of another touch pad;
FIG. 12 is perspective view of a modified coin-operated apparatus with a blocking bar;
FIG. 13 is a section on line 13--13 of FIG. 12; and
FIG. 14 is a simplified electrical block diagram.
Referring first to FIGS. 1-3, an arm-wrestling apparatus 10 comprises a support 12, such as a suitable table, having an upper top or horizontal supporting surface 14 for the contestants' elbows. Fixed to this surface are a pair of elbow rests or cups in which the players place their elbows as illustrated in broken lines in FIG. 1. These elbow rests or cups, which are described in my earlier-mentioned prior U.S. Pat. No. 3,649,010 and form no part of the present invention, define fixed positions P for the contestants' elbows.
In a conventional arm-wrestling match without the aid of scoring apparatus, each scoring position is that in which the contestants' forearms extend generally parallel to the surface 14 with the hand and/or wrist of one contestant in contact with the surface. This position constitutes a win or score for the other contestant. It is often quite difficult to determine when a contestant has thus won or scored.
This invention provides scoring apparatus 17 for eliminating this problem. It comprises a pair of touch pad means 18 mounted on the elbow support 12 at opposite sides of the fixed elbow positions P. These touch pad means include depressible touch pads 20 which are located at opposite sides of the fixed elbow positions for engagement and depression by the contestants' hands when their forearms are down in scoring position. Each touch pad means 18 also includes means 22 for indicating depression of the corresponding touch pad 20. In this particular inventive embodiment, which is particularly suited for use in team wrestling matches, the depression indicating means 22 of each touch pad means 18 comprises point readout means 24 for displaying the distance through which the corresponding touch pad 20 is depressed from its normal or undepressed position, to permit awarding of numerical scores to the contestants and electrically actuated signal means 26 which are activated in response to depression of a touch pad through its full range of depression.
In this embodiment, the contestants complete in the usual way with their elbows positioned in the elbow cups 16. Upon movement of the contestants' forearms to either scoring position, a contestant's hand is pressed against a corresponding touch pad 20, depressing the pad and actuating the indicating means 22. The maximum distance through which the pad has been depressed may be observed on the readout means 24 which is calibrated in terms of game points which may be awarded to the scoring contestant. Actuation of the electrical signal means 26 indicates that the touch pad has been depressed through its full range of depression and that a scoring contestant has won.
Referring now in more detail to FIGS. 1 through 3, each touch pad means 18 comprises an upstanding post 28 which is shown as a hollow rectangular tube. The lower end of this post extends through an opening in the top of table 12 and is welded or otherwise rigidly joined to a mounting plate 30 which is firmly attached by screws 32 to the underside of the table top. Extending laterally of the post 28 at a position relatively close to, but spaced from, the elbow-supporting surface 14 is a pivoted cross arm 34. This cross arm has a pair of spaced parallel arm members 36 which are rigidly joined by connecting webs 38 and straddle the post 28. Cross arm 34 is pivotally attached to the post 28 by a pivot bolt 35 which extends through the cross arm members 36 and the post. Interposed between the post 28 and the cross arm members 36 are washers 40 (FIG. 3). A compression spring 42 is mounted on the bolt 35 between the bolt head 44 and the adjacent cross arm member 36, and a second compression spring 42 is mounted on the bolt between a nut 46 threaded on the bolt and the adjacent cross arm member 36. Referring to FIG. 3, it will be seen that the springs 42 exert inward pressure against the cross arm members 36, tending to urge the arm members inwardly toward the post 28, and that the nut 46 may be threaded on the bolt to increase and reduce this spring pressure. The spring pressure is provided to cause friction in the pivot joint.
As shown in FIG. 1, the posts 28 are located at opposite sides of a line passing through the centers of the elbow cups 16, and hence through the elbow positions P, and substantially in a common plane passing midway between the elbow cups substantially normal to their line of centers. The pivot axes of the touch pad cross arms 34 parallel one another and approximately parallel the line of centers between the elbow cups. Accordingly, the cross arms 34 have inner ends which extend inwardly toward the line of centers of the elbow cups and opposite outer ends. The inner extending portion of the cross arms are somewhat longer than their outer ends, as at 38.
The touch pads 20 are rectangular cushioned pads which are firmly attached to and extend crosswise of the inner extremities of the cross arms 34. In the normal positions of these pads, shown in FIG. 1 and in broken lines in FIG. 2, the cross arms 34 are horizontal. It will be understood, of course, that the cross arms are located the same distance above the elbow-supporting surface 14, such that in these normal positions the touch pads are located in a common plane parallel to and spaced some distance above the elbow-supporting surface 14. As may be observed in the drawings, the touch pads 20 are located at opposite sides of the elbow cups 16 and provide the fixed elbow positions P for engagement and depression by the contestants' hands in the scoring positions referred to earlier.
As noted earlier, the compression springs 42 of each touch pad means 18 exert inward pressure against the cross arm members 36, tending to deflect these members inwardly toward the post 28. According to the present invention, the spring pressure is adjusted by means of the nut 46 on the pivot bolt 35 to effect frictional retention of the cross arm 34 in fixed position relative to the post 28. Accordingly, a cross arm 34 will remain in any angular position relative to its post 28, to which it has been pushed, until a downward force is exerted on the arm.
At the beginning of play, the touch pads 20 are placed in their initial positions of FIG. 1 and, as shown above, will remain in these positions. During a match, movement of a contestant's forearm to a scoring position pushes the corresponding touch pad downward, depressing it toward the elbow-supporting pad or surface 14. As noted earlier, the amount of such depression is indicated by the indicating means 22.
The readout means 24 of each touch pad means 18 comprises a scale plate 48 which is attached to the outer side of the corresponding post 28 and is straddled by the outer ends of the cross arm members 36. Marked on this scale plate are indicia constituting a scale across which the outer end of the cross arm 34 moves as a pointer to indicate the distance through which the touch pad 20 has been depressed from its normal position. In the particular embodiment illustrated, the upper outer edge 52 of the front cross arm member 36 serves as a reference or pointer against which the scale 50 is readable to indicate the depression distance of the touch pad. Scale 50 is calibrated in terms of scoring points, e.g., 1 to 3, which may be awarded to a contestant. It will be understood, of course, that the scale 50 reads zero when the touch pad 20 occupies its normal pre-game position. In the particular embodiment shown, maximum or full range depression of the touch pad corresponds to three points on the scale 50.
The electrical signal means 26 of each touch pad means 18 comprises a lamp 54, preferably a rotating or flashing beacon, mounted on the upper end of the post 28. The leads of the lamp extend downwardly through the hollow interior of the post. The electrical signal means 26 may also include a buzzer 58.
Signal lamp 54 and buzzer 58 of each touch pad means 18 are energized from a suitable transformer 60 through a switch 62 mounted on a switch bracket 64 secured to the lower end of the post 28. Switch 62 is arranged to be actuated, to energize the lamp 54 and the buzzer 58, by contact with the cross arm 34 upon downward depression of the touch pad 20 to its lower limiting position shown in full lines in FIG. 2.
The operation of the arm-wrestling scoring apparatus 17 will now be described. At the start of a match, the touch pads 20 are elevated to their normal pre-game positions of FIG. 1. The signal lamps 54 and buzzers 58 of the touch pad means 18 will then be de-energized. If, in the course of the wrestling match, either contenstant succeeds in pressing his opponent's arm to a scoring position, the corresponding touch pad 20 will be depressed. If the touch pad is only partially depressed, the corresponding signal lamp 54 and buzzer 58 will remain de-energized. In this case, the amount of depression of the touch pad is observed on the scale 50 and recorded for subsequent awarding of the corresponding number of points to the contestant. The wrestling match may continue until one or the other of the contestants succeeds in pressing his opponent's arm sufficiently hard down to effect full depression of the corresponding touch pad 20. When this occurs, the corresponding switch 62 is actuated to energize the signal lamp 54 and buzzer 58, and thereby signal the end of the match.
Turning now to FIG. 4, there is illustrated a modified scoring apparatus 100 according to the invention. It comprises a pair of cushioned rectangular touch pads 102 located at opposite sides of a pair of elbow cups 104 (only one shown) secured to the top elbow support surface 106 of a wrestling table 108. The longitudinal edges of the touch pads parallel one another and approximately parallel the line of centers between the elbow cups and extend normal to the plane of the paper in FIG. 4. The touch pads are pivotally attached, along their adjacent inner longitudinal edges, to the surface 106 by hinges 110. Mounted on the table 108, below the outer edges of the touch pads 102, are electrical switches 112 having plungers 114 which engage the under sides of the pads. These plungers are biased upwardly toward the pads by springs (not shown) contained in the switches. The touch pads are depressible downwardly against the force of these switch springs to actuate the switches and are returned upwardly by the springs when the pads are released. As in the previous embodiment of the invention, the touch pads 102 are disposed at opposite sides of the elbow cups 104 for engagement and depression by the clasped hands of the contestants' wrestling arms when their forearms move to scoring positions.
The scoring apparatus 100 also includes indicating means 116 for indicating depression of the respective touch pads 102. In this case, the indicating means 112 comprise signal lamps 118, which are preferably rotating or flashing beacons, mounted on the upper ends of supporting posts 120 attached to the table 108, in the manner shown in FIG. 4, and buzzers 122 secured to the underside of the table. The switch 112, signal lamp 118, and buzzer 122 for each touch pad 102 are connected in circuit with one another and with a transformer 124 secured to the underside of the table, so that depression of the pad energizes the lamp and buzzer.
The arm-wrestling apparatus of FIG. 4 is used in essentially the same manner as that of FIGS. 1 through 3. Accordingly, no further description of the modified scoring apparatus is deemed necessary, except to say that the apparatus is operative only to indicate the winner of a wrestling match and has no provision for awarding of point scores to the individual contestants.
In the inventive embodiments described thus far, the touch pads, when fully depressed, project above the elbow-supporting surface. This may present a safety hazard in some cases, as in a wrestling match between relatively powerful contestants, due to the possibility of a contestant's wrist being bent to the point of injury about the edge of a pad following particularly hard contact of the contestants' hands with the pad. FIGS. 5 and 6 illustrate a modified touch pad arrangement according to the invention which eliminates this safety hazard. In this case, the cushioned rectangular touch pad 202 is mounted within a complementary recess 204 in the elbow-supporting surface 206 of the wrestling table. Acting between the bottom of this recess and the bottom of the touch pad are compression springs 208 for urging the touch pad upwardly to its extended position of FIG. 6, wherein a stop shoulder or flange 210 about the bottom of the touch pad engages a coacting stop shoulder or flange 212 about the open top side of the recess 204. Mounted at the bottom of the recess 204 is a switch 214 having an upper plunger 216 which is engaged and depressed by the touch pad 202, to actuate the switch, when the touch pad is depressed to its position of FIG. 5. Switch 214 actuates the indicating means (not shown) for indicating depression of the touch pad.
When in its extended position of FIG. 6, the touch pad 202 projects a distance above the wrestling table surface 206 for engagement and depression of the pad by the contestants' hands during a wrestling match. In its depressed position of FIG. 5, however, the upper surface of the pad is relatively flush with the table surface, thus eliminating the safety hazard discussed above.
The modified touch pad 300 of FIG. 7 comprises a base member 302 and a pad cushion 304 overlying and secured to the base member. The cushion 304 may be constructed of foam rubber or other suitable resilient material. Interposed between the touch pad base member 302 and cushion pad 304 is a switch tape 306 including switch tapes 308 which are secured to the base member and the pad, respectively, one over the other. These switch tapes are attached to leads 310 extending from one end of the touch pad.
In the absence of any downward pressure on the cushion pad 304, the switch tapes 308 are spaced and thus present an open circuit between the switch leads 310. Downward pressure at any point on the pad 304 forces the switch tapes 308 into contact with one another, thereby completing an electrical circuit between the switch leads 310. This modified touch pad may be mounted directly on the elbow-supporting surface of the wrestling table or within a recess in the table, in the manner of the touch pad in FIGS. 5 and 6.
In addition to the possible uses described thus far for scoring apparatus according to the invention, such apparatus may be also installed in clubs, bars, cocktail lounges, and other public or private facilities for use by the patrons and may, if desired, be equipped with a coin mechanism for activating the apparatus.
FIGS. 8-14 show game apparatus of the coin-operated type. The main features are the novel means provided to prevent use of the apparatus without inserting a coin.
FIGS. 8-10 show such an apparatus where the prevention or "lockout" means is in a special support means for theelbow pads. When no coin has been fed into the slot the elbow pads are unsupported, except for light springs, and are free to sink downward into the table top for a distance of several inches or so. This makes wrist-wrestling impossible. When a coin has been inserted, a lockout drive mechanism automatically moves a support bar or lock bar into position under both elbow pads, holding them up solidly in position and permitting play to proceed.
In FIG. 8, a perspective view of this modification built on a table or the like indicated generally at 400, the elbow pads are shown at 405a and 405b, each surrounded by a circular cushion-like elbow cup 404a, 404b, respectively, generally like the cups 16 in FIG. 1. Referring now to FIGS. 9-10, the elbow-support pads 405a, 405b, are shown in section in the "up" or playing position. They are shown in phantom lines as at 405'b in the depressed, play-inhibiting or lockout position. Each pad is preferably connected to the table top by light springs 411 which permit it to be pushed freely downward unless the locking bar is up in place. The locking bar is shown at 410 in the "up" or playing position and in phantom lines 410' in the depressed position, which it occupies when no coin has been inserted in the coin acceptor 401 (FIG. 8).
The elbow pad-locking mechanism is shown further in FIG. 10. Pad-locking bar 410 extends under both elbow pads 405a, 405b and carries a nut 413 in its center. A screw 412 is rotated by a suitable gearhead motor or the like 416 via a suitable drive, such as a chain and sprocket, indicated generally at 415. When a coin is inserted in coin acceptor 401, suitable circuitry applies drive power to the motor 416, which rotates the screw 412 and elevates the locking bar 410 up to support the elbow pads 405a, 405b in playing position. A suitable limit switch means, not shown, is employed to turn off the motor 416 when the locking bar is at either end of its travel. Other suitable circuitry of known type energizes the motor 416 in reverse when one of the touch pads has been actuated to signal the end of the game. The motor 416 then screws the locking bar 410 back down into the "lockout" position.
FIG. 11 is a side sectional view of a touch pad for scoring, showing a preferred construction. The pad 406 is hinged to the top of table 400 by a suitable hinge 420. A suitable plunger-actuated switch 422 or the like is mounted under a hole in the table top, disposed to have its plunger 421 pushed down by the side of the pad 406 opposite the hinge side. A suitable compression spring 421 is provided to bias the pad upward.
FIGS. 12 and 13 show an alternative form of lockout means to prevent arm-wrestling play when no coin has been inserted in the acceptor 401. The perspective view of FIG. 12 is the same as FIG. 8, except for the lockout device 451. This device is herein called a blocking bar. Preferably it has a spider-like shape as shown with four generally radiating arms. These arms are so disposed that they will lie flat on the table, clearing the elbow cups 404a, 404b and the touch pads 406a, 406b, to permit normal play when the bar 451 is in the "down" position. A drive mechanism lowers the blocking bar 451 to this "down" position when the coin acceptor 401 is actuated. When the coin acceptor has not been actuated by the insertion of a coin, or the game is over, however, the drive mechanism raises the blocking bar 451 up to a blocking or "lockout" position 30 cm or so above the table. When it is in this raised position, it interferes with players' arms, preventing scoring and making arm-wrestling impossible.
FIG. 13 shows the lockout means drive mechanism for raising and lowering the blocking bar, in simplified form. In this sectional view, the blocking bar 451 is attached to a hollow sleeve 456 which extends vertically through a hole in the table 400. A screw 453, which may be a ball screw of known type, actuates a suitable nut 454 which is so disposed as to raise and lower the bar 451. The screw 453 may be rotated in either direction by a reversible motor means 416', which may be a suitable small gearhead motor like motor 416 of FIG. 10. When the coin acceptor 401 is actuated by inserting a coin in it, suitable circuitry, not shown in FIG. 13, turns on the motor 416' in a direction to lower the blocking bar 451 down to table level to permit the players to wrist-wrestle. After a "win" has been signaled by the closure of one of the switches under touch pad 406a or 406b, the motor is started in reverse and rotates screw 453 to raise blocking bar 451 into blocking or "lockout" position.
A safety feature is provided to prevent a person's hand being caught under the blocking bar as the motor is pulling it down. This "free-wheeling" or safety sleeve feature comprises sleeves 455 and 456. Sleeve or tube 455 is fixed to the ball screw nut 454. Means, not shown, are provided to prevent rotation of this sleeve so that the screw will screw it up and down. A second sleeve 456 is attached to the blocking bar 451 at its top end and is a free-sliding fit over the driven sleeve 455. Thus, the blocking bar can be freely pulled upward by hand, but cannot be pushed downward when the motor has raised it into blocking position. Guide and stop means, not shown, are provided to prevent rotation of bar sleeve 456 and to prevent its removal from above. These may be of any suitable known design.
The motor means 416', FIG. 13, may be supported on a suitable bracket 417 as shown.
FIG. 14 is a simplified block diagram of a suitable electrical circuit for controlling signal lights, blocking devices, and the like. A sequence of operation is as follows. At the start, the blocking device, whether the locking bar of FIGS. 8-9 or the blocking bar of FIGS. 12-13, is in the "blocking" lockout position to prevent play, and a suitable "OFF" indicator lamp 506 (FIGS. 8, 14) is lit. A coin is inserted in the coin acceptor 401, FIG. 14, closing contacts which start motor 416. Motor 416 actuates the blocking device, such as bar 451, into the non-blocking or "play" position and lights an "ON" indicator 502. The players sit down, and each grasps one of the free-hand handles 403 and depresses its thumb-switch push-button 407 (FIGS. 8, 12, 14). Both handle switches are connected in series. When both are closed, FIG. 14, a "READY" lamp 504 lights and a timer 503 is started. After a suitable interval, such as several seconds, the timer causes a "GO" indicator lamp 505 to light. The players proceed to wrist-wrestle. When one player forces the other's wrist against his touch pad 406a or 406b, a switch 422 is closed (see 422 in FIG. 11). Either such "win" switch will actuate a motor-reversing relay 501, FIG. 14, and a "WIN" indicator lamp 408a or 408b lights. These last-mentioned lights are preferably conspicuous in appearance and may be equipped with flashers. The motor-reversing relay 501 causes the motor 416 or the like to actuate the blocking device into the blocked position, as by raising the blocking bar 451 or by lowering the lock bar 410 of FIG. 9. | A coin-operable amusement device which provides table equipment and scoring apparatus for arm wrestling contests. For each player there is provided an elbow cup, a fixed handle for the player's free hand, and a touch pad which actuates a scoring indicator. When the losing player's arm is forced down against a touch pad, signal devices operate. In one form the touch pads are depressible for a substantial distance and carry pointers movable along scales which are calibrated in game points. Friction linkages make the pointers remain where deflected. Means are provided to prevent play unless a coin has been inserted into a coin acceptor. One such means comprises a depressible support under each elbow cup, which is locked up in place only when a coin has been inserted. An alternative means is a bar-like blocking element disposed so as to interfere with play when it is raised above the table top. When a coin is inserted, an automatic mechanism lowers the blocking bar out of the way. Fixed handles for the players' free hands may be provided, with thumb-actuated pushbutton switches which energize a "READY" signal when both are depressed. | 0 |
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional application No. 62/332,933, filed May 6, 2016, which is incorporated by reference in its entirety herein.
TECHNICAL FIELD
[0002] This invention relates generally to light emitting diode lighting applications and more specifically to control arrangements for light emitting diode lighting applications.
BACKGROUND
[0003] Light emitting diode (LED) lighting solutions are replacing incandescent lighting and other less efficient solutions in a number of areas such as automotive headlamps. LEDs are more energy efficient, convert less energy to heat, and last much longer than incandescent bulbs. However, LED lighting solutions use more individual lighting elements than their incandescent counterparts.
[0004] LED lighting solutions typically arrange LED lighting elements into a matrix. Depending on the application, an LED matrix can be controlled using an integrated circuit that drives individual LED lighting elements. LED control is often achieved by commutating LED current through a parallel/bypass switch, a process commonly known as shunt or parallel switch dimming. Depending upon the required power/lumen output there can be multiple LEDs in series or parallel, fed by a current source or sink. In many cases, to achieve control of individual LEDs, each LED is bypassed by a switch and controlled using standard pulse width modulation (PWM) dimming techniques. When an overvoltage condition exists across a control switch, the control switch is closed to shunt the current that otherwise flowed through the LED. Large amounts of current flowing through the switch, however, can cause damage to and limit the longevity of a control device.
SUMMARY
[0005] Generally speaking, pursuant to the following embodiments, light emitting diode systems according to the following description allow for high current end user LED matrix applications while mitigating internal damage to control circuitry that may be caused by excess current flow. In one example, multiple switches operate in parallel across an LED. When an overvoltage condition is detected in a first switch, a logic circuit determines those switches programmed to operate in parallel and causes them to conduct current. This reduces the amount of current flowing through any one switch and mitigates harm to the device.
[0006] In one example, the parallel configuration of switches allows those switches to be driven by a single pulse width modulated current. This allows the drive current to be divided between parallel transistors, limiting the damaging effects that can be caused by high currents flowing through the switches.
[0007] These and other benefits may be clearer upon making a thorough review and study of the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 illustrates a functional block diagram of an example integrated circuit for controlling LEDs as configured in accordance with various embodiments of the invention.
[0009] FIG. 2 illustrates a circuit diagram of an example switch and LED configuration as configured in accordance with various embodiments of the invention.
[0010] FIG. 3 illustrates a circuit diagram of an example paralleled switch configuration across an LED as configured in accordance with various embodiments of the invention.
[0011] FIG. 4 illustrates a circuit diagram of parts of an example control circuit as configured in accordance with various embodiments of the invention.
[0012] FIG. 5 illustrates a circuit diagram of an example approach to individual parallel switch dimming across a single string of LEDs as configured in accordance with various embodiments of the invention.
[0013] FIG. 6 illustrates a circuit diagram of an example approach to individual parallel switch dimming across multiple strings of LEDs as configured in accordance with various embodiments of the invention.
[0014] FIG. 7 illustrates a block diagram of parts of a logic and registers circuit as configured in accordance with various embodiments of the invention.
[0015] FIG. 8 illustrates example logic signals for controlling parallel switches as configured in accordance with various embodiments of the invention.
[0016] FIG. 9 illustrates a flow chart of an example method of operation as configured in accordance with various embodiments of the invention.
[0017] Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted to facilitate a less obstructed view of these various embodiments. It will further be appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by persons skilled in the technical field as set forth above except where different specific meanings have otherwise been set forth herein.
DETAILED DESCRIPTION
[0018] Referring now to the figures, FIG. 1 is a functional block diagram illustrating components of an integrated circuit 100 , in this case, an example apparatus for light emitting diode systems. The integrated circuit has voltage inputs VIN 180 , a 5V input 181 , and a 3.3V input 182 . Inputs 181 and 182 are connected to linear regulators and references circuit 117 , which is connected to ground line 183 . The input 180 is connected to both the charge pumps 115 and the linear regulators and references circuit 117 . The analog to digital converter (ADC) 188 may be driven by an external voltage AREF 184 . Inputs 185 and 186 are general purpose inputs which can be used, for example, for temperature compensation, binning, or coding. These inputs are fed into the AMUX 187 , the output which is fed into the ADC 188 , which provides input to the logic and registers 105 . Additionally, an address pin (not illustrated) of the integrated circuit 100 is connected to the ADC to extend the addressability of the integrated circuit 100 from eight to thirty-one devices.
[0019] Inputs SDA 189 and SCL 190 are I2C data and clock inputs, respectively, for this example implementation. SDA 189 and SCL 190 are connected to the UART to I2C circuit 110 . The UART to I2C circuit 110 receives data corresponding to the desired PWM information for internal switches, for example, 122 , 124 and 126 . In addition, the UART to I2C circuit 110 can send back fault and other diagnostic data to the host, not illustrated. SYNC input 192 receives a synchronization signal so multiple of the integrated circuits 100 can be synchronized across a network. SYNC functionality can be programmed through a serial interface. Input RX 193 and output TX 194 are used to communicated between networked ones of the integrated circuit 100 .
[0020] In this example, input CLK 195 serves as the primary clock for the integrated circuit 100 . Input XTALI 197 is an input to a Pierce oscillator inverter and can be connected to an external crystal circuit. The output XTALO 196 is an output of a Pierce oscillator invertor and can be connected to an external crystal circuit. The XTAL detect circuit 198 connects the XTALO 196 to the system clock only if there have been at least sixteen rising edges on XTALO 196 .
[0021] The integrated circuit 100 contains a plurality of configurable switch banks, each switch bank having one or more switches configured to electrically connect to at least one light emitting diode to drive the at least one light emitting diode. A switch bank may, for example, comprise three switches; however, a switch bank may contain any number of switches. The integrated circuit 100 may contain any number of switch banks configured as described. In one example, the integrated circuit 100 contains four switch banks each containing three switches. In the illustrated exemplary integrated circuit 100 , switches 122 , 124 , and 126 form one switch bank 120 , switches 132 , 134 , and 136 form one switch bank 130 , switches 142 , 144 , and 146 form one switch bank 140 , and switches 152 , 154 , and 156 form another switch bank 150 .
[0022] FIG. 2 illustrates exemplary individual switch banks 120 , 130 , 140 , and 150 . As illustrated, each switch bank may contain three series switches. For example, switch bank 120 contains switches 122 , 124 , and 126 . The switch banks 120 , 130 , 140 , and 150 may be arranged in other ways, for example, as a series combination of twelve switches; a parallel combination of two, three, or four banks of three switches each; or four individual ground referenced three-switch banks. The switch banks 120 , 130 , 140 , and 150 can be configured in any other intermediate series-parallel switch combination. For instance, FIG. 3 illustrates an exemplary series of LEDs, each LED having two switches arranged in parallel across an LED. In this example arrangement, the switches 122 , 124 , and 126 of switch bank 120 have bank placed in parallel with the switch 132 , 134 , and 136 of switch bank 130 respectively.
[0023] Referring again to FIG. 1 , the integrated circuit 100 further contains a control circuit 101 configured to selectively control at least a first switch 122 of a first switch bank 120 and at least a first switch 132 of a second switch bank 130 , in parallel. Control circuit 101 receives input from the UART to I2C circuit 110 and drives the switches of the integrated circuit 100 accordingly. The switches may be controlled, for example, by standard pulse width modulation dimming techniques. The control circuit 101 is configured to detect a voltage condition of one of the first switch 122 of the first bank 120 or the first switch 132 of the second bank 130 . In one example, illustrated in FIG. 3 , a first switch 122 of a first switch bank 120 may be arranged in parallel with a first switch 132 of a second switch bank 130 by programming the logic and registers 105 . So arranged, the control circuit 101 is configured to cause the first switch of the second switch bank, 132 , to conduct current based at least in part on the voltage condition in the first switch of the first switch bank, 122 . For example, when the voltage condition in switch 122 is detected to be outside some threshold, the control circuit 101 will cause the switch 132 to conduct current. In a more specific example, the control circuit 101 is configured to cause the first switch of the second switch bank, 132 , to conduct current in response detecting that the voltage condition is above a threshold voltage for the first switch of the first switch bank 122 .
[0024] In one example, the control circuit 101 is configured to determine when the first switch bank 120 and the second switch bank 130 are configured to be controlled in parallel and, in response, apply a driving signal synchronously to both the first switch bank 120 and the second switch bank 130 . For example, FIG. 5 illustrates a single pulse width modulated signal being applied to a single series of a LEDs. A similar signal may be applied to multiple series strings of LEDs as illustrated in FIG. 6 . In high power applications, it is advantageous to place multiple banks of switches in parallel with a single series string of LEDs as illustrated in FIG. 3 . In the arrangement of FIG. 3 , the control circuit 101 will recognize that the switch banks, 120 and 130 , are programmed to operate in parallel and drive the switch banks with the same pulse width modulated signal. Such an arrangement is advantageous because the drive current does not need to flow through a single switch.
[0025] The control circuit 101 includes a plurality of driver circuits 400 - 411 and a register, wherein individual ones of the plurality of driver circuits are connected to drive individual ones of the first switch bank's 120 one or more switches 122 , 124 , and 126 and the second switch bank's 130 one or more switches 132 , 134 , and 136 . In one example, the driver circuits 400 - 411 communicate with the logic and registers 105 via level shifters 300 - 311 . In the exemplary illustration of FIG. 4 the driver 400 is coupled to level shifters 330 and 370 . The driver circuits 400 - 411 are substantially similar, and for ease of description the drivers 400 - 411 will be described by example in view of the driver circuit 400 as illustrated in FIG. 4 . As illustrated in FIG. 7 the register may be, for example, a fault register 701 and be contained within the logic and registers 105 . The fault register 701 stores the fault status of LEDs arranged in parallel with the switches of the integrated circuit 100 . As can be seen from FIG. 4 , the driver circuit 400 has the internal ability to cause its own switch 122 to conduct current when the driver circuit detects an overvoltage condition without needing to signal the logic circuit in the logic and registers 105 . To further protect the switch 122 from damage, the driver 400 employs switch 405 . For example, in response to the comparator's 440 detecting an overvoltage condition, the switch 405 will drive the gate of switch 122 HIGH via the inverter 425 in approximately 50-100 nano-seconds whereas it takes approximately 20 micro-seconds for the gate driver to respond. The driver 400 communicates the fault status of an LED corresponding to a switch 122 to logic and registers 105 via latch 420 where it is received by the fault register 701 . The OR gate 415 takes input from the latch 420 and the gate driver level shift circuit 330 . If the input from either latch 420 or level shift circuit 330 is logic HIGH, the OR logic will cause the gate driver 410 to power the gate of the switch 122 causing it to conduct current and bypassing the corresponding LED. Input from the gate driver level shift circuit 330 can cause the latch 420 to reset.
[0026] As illustrated in FIG. 4 , individual ones of the plurality of driver circuits 400 include an overvoltage detection circuit 440 configured to compare a voltage 445 across a switch 122 to an overvoltage threshold voltage 450 and, in response to detecting that the voltage 445 across the switch 122 exceeds the overvoltage threshold voltage 450 , sending a fault detection signal to the fault register 701 . In this approach, the driver circuit 300 also includes a short condition detection circuit 435 configured to compare the voltage 445 across the switch 122 to a short circuit condition voltage 455 threshold and, in response to detecting that the voltage 445 across the switch 122 is below the short circuit condition voltage 455 , send a fault detection signal to the register. For example, an internal comparator 440 monitors the drain-to-source voltage of the internal switch 122 . If the voltage exceeds a threshold, for instance in the event of an open LED failure or overvoltage condition, the device overrides the switch-off signal and turns on the switch 122 thereby maintaining current flow to the rest of the LED string in the presence of a faulty or damaged LED and protects the switch 122 . The driver circuit 400 causes the corresponding bit of the fault register 701 in the logic and registers 105 to be set. In a similar example, the driver circuit 400 can detect an LED open detection or under voltage condition of an LED by monitoring the drain-to-source voltage 445 of the internal switch 122 . In another example, the voltage condition indicates one of an effectively open circuit condition or an effectively short circuit condition for the one or more light emitting diodes. The driver circuit 400 then causes the logic and registers 105 to set the fault register and send signals to close the switches that are arranged in parallel based on the effectively short circuit condition or the effectively open circuit condition. The logic and registers 105 contain an over voltage limit register. The overvoltage limit register 460 can be set via the UART to I2C circuit 110 to control the effectively open voltage condition. The effectively open voltage condition is a voltage greater than the voltage set in the overvoltage limit register 460 . The effectively short voltage is any voltage less than the ref short voltage 455 .
[0027] In one example, the control circuit 101 further comprises a parallel configuration register 703 configured, at least in part, to specify an association between individual ones of the first switch bank's 120 one or more switches 122 , 124 , and 126 and the second switch bank's 130 one or more switches 132 , 134 , and 136 . The parallel configuration register 703 is contained in the logic and registers 105 and may be programmed to configure the available switch banks as a series combination of switches; a parallel combination switches; or individual ground referenced three-switch banks. The switch banks can be configured in any other intermediate series-parallel switch combination. The parallel configuration register of integrated circuit 100 is to programmed to set the applied paralleling configuration and is contained in the logic and registers 105 . The parallel configuration register may be set, for example, by an external MCU communicating with the logic and registers 105 through UART to I2C circuit 110 .
[0028] As illustrated in FIG. 7 , the logic and registers 105 of the control circuit 101 includes a logic circuit 702 , the logic circuit operable to control individual ones of the first switch bank's 120 one or more switches 122 , 124 , and 126 based at least in part on the voltage condition of the second switch bank's 130 one or more switches 132 , 134 , and 136 and the association between individual ones of the first switch bank's 120 one or more switches 122 , 124 , and 126 and the second switch bank's 130 one or more switches 132 , 134 , 136 . The logic circuit 702 may be coupled a fault register 701 . The fault register 701 configured to store a fault status of one or more light emitting diodes arranged electrically in parallel with one or more of the plurality of switches of the integrated circuit 100 . The logic circuit 702 may be coupled to, for example, the parallel configuration register 703 , the fault register 702 , and each driver circuit 400 - 411 . In one example, upon receiving a fault status signal from the driver 400 , the logic circuit 702 determines which switches are programmed to operate in parallel with the switch for which the driver 400 reported a fault status based on the content of the parallel configuration register 703 and causes those switches to close by signaling their respective driver 400 . In another example, after a driver circuit 400 communicates a fault status corresponding to an LED arranged in parallel with a switch 122 , to the fault register 701 , the fault register 701 and the parallel configuration register 703 will be polled. If other switches are programmed to operate in parallel with the switch 122 for which the driver 400 communicated a fault status signal to the logic circuit 702 , the logic circuit 702 will cause those switches programmed to operate in parallel with switch 122 to close (i.e., conduct current).
[0029] FIG. 8 is a logic signal diagram. Signals ov[m] 803 and fault[m] 804 are output from the driver circuit 400 through sync & level shift to fault register circuit 370 to the logic and registers 105 and are synchronized to the system clock. The signals ov[m] 803 and fault[m] 804 separately, together, or in combination may be considered a fault status signal. The sys_c signal 805 represents the frequency of the system clock. The arrow 811 represents the point in time in which the logic and registers 105 can read the signals from the driver 400 and cause switches programmed to operate in parallel to be closed. There is a delay of a number of clock cycles between when the driver 400 detects an overvoltage condition and when the logic and registers 105 can close the switches 122 programmed to be in parallel. The actual gate drive[m] 801 and actual gate drive[n] 809 signals illustrate this delay. The delay is much shorter in the driver 400 that detected the overvoltage condition because the driver 400 internally closed its own switch in response to detecting the overvoltage condition. The signal gate drv[m] 802 and the signal gate drv[n] 810 are inputs to the driver 400 . In the case of an overvoltage or under voltage condition being detected in a first switch 122 , the logic and registers 105 will determine the switches of the integrates circuit 100 programmed to be in parallel with the first switch and cause those switches to close by transmitting a gate drv[n] signal 810 to a gate driver level shift block 330 of a driver 400 . Once received, the signal will cause the OR gate 415 to transmit logic HIGH to the gate driver and close the switch.
[0030] The fault[m] 804 signal is synchronized to the system clock and represented by s_fault[m] 807 . The logic and registers 105 uses the signal s_fault[m] 807 to determine an under voltage condition. For example, the logic and registers 105 will close the switch of the driver 400 and any other driver 400 that were programmed to be in parallel when an under voltage condition is determined.
[0031] The output signal from the comparator 435 may be combined using OR logic at sync and level shift to fault register circuit 370 with an output of the latch 420 . In such a case the logic and registers 105 will not be able to distinguish whether an under voltage condition or an over voltage condition has occurred; however, if one of those conditions did occur, the logic and registers will determine which switches to close based on the contents of the parallel configuration register 703 .
[0032] As illustrated in FIG. 8 by arrow 812 the synchronized fault inputs are latched into the FAULT registers on the falling edge of the requested LED ON time to allow the controller to poll which LEDs had an open or short fault at the end of the LED ON pulse. The s_fault[m] signal 807 is sampled a number of clock cycles prior to the falling edge of the requested LED PWM[m] signal 800 , and bits in the fault register 701 in the logic and circuits 105 corresponding to the switch 122 corresponding to the s_fault[m] 807 signal are set in response to the s_fault_lat[m] signal 808 .
[0033] FIG. 9 is a flow chart illustrating an example operation of an integrated circuit device controlling programmed parallel switches as described above. At step 900 the integrated circuit is programmed by an external device to create a series/parallel relationship between switches of the switch banks 120 , 130 , 140 , and 150 . For example, the integrated circuit 100 may associate a first configurable switch bank 120 and a second configurable switch bank 130 by programming the first configurable switch bank 120 to operate in parallel to the second configurable switch bank 130 . The association may be in response to input from an external MCU. At step 901 , the control circuit 101 determines which switches are programmed to be in parallel by using a parallel configuration register 703 in the logic and registers 105 . For example, the integrated circuit 100 may determine whether individual ones of the switches of the first configurable switch bank 120 and the second configurable switch bank 130 are programmed to operate in parallel based on the association.
[0034] Optionally, at step 902 the integrated circuit 100 can drive switch banks arranged in parallel with a synchronous pulse width modulated signal. For example, the integrated circuit 100 may perform the step of applying a driving signal synchronously to both the first configurable switch bank 120 and the second configurable switch bank 130 when the first configurable switch bank 120 and the second configurable switch bank 130 are configured to operate in parallel.
[0035] At step 903 the control circuit 101 controls, for example, a switch 132 because it is programmed to be parallel to switch 122 . The control circuit 101 may cause switch 132 to conduct current because of a voltage condition detected in the switch 122 . For example, the integrated circuit 100 may control the individual ones of the switches of the second switch bank 130 based on voltage conditions in individual ones of the switches in the first configurable switch bank 120 and the association between individual ones of the first switch bank's 120 one or more switches 122 , 124 , and 126 and the second switch bank's 130 one or more switches 132 , 134 , and 136 . The voltage condition may be, for example, an effectively open circuit condition or an effectively short circuit condition. For example, the integrated circuit 100 may cause a first switch of the second switch bank to conduct current based on the voltage condition in a first switch of the first switch bank when the voltage condition is one of an effectively open circuit condition or an effectively short circuit condition.
[0036] Optionally, at step 904 the control circuit 101 stores a fault status of one more LEDs corresponding to the switches of the integrated circuit 100 . For example, the integrated circuit 100 stores a fault status of one or more light emitting diodes arranged in parallel with one or more of the plurality of switches of the first and the second configurable switch banks, 120 and 130 . In response to the driver circuit's 400 detecting an overvoltage or under voltage condition of a corresponding switch 122 , the driver circuit 400 communicates a fault status to the logic and registers 105 . For example, the integrated circuit 100 stores a fault status of one or more light emitting diodes arranged in parallel with one or more of the plurality of switches of the first and the second configurable switch banks, 120 and 130 . The logic and registers 105 uses the parallel configuration register 703 to determine those switches programmed to be in parallel with the switch 122 whose driver 300 reported a fault and causes those switches to conduct current.
[0037] Certain terms are used throughout the description and the claims to refer to particular system components. As one skilled in the art will appreciate, components in digital systems may be referred to by different names and/or may be combined in ways not shown herein without departing from the described functionality. This document does not intend to distinguish between components that differ in name but not function. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” and derivatives thereof are intended to mean an indirect, direct, optical, and/or wireless electrical connection. Thus, if a first device couples to a second device, that connection may be through a direct electrical connection, through an indirect electrical connection via other devices and connections, through an optical electrical connection, and/or through a wireless electrical connection.
[0038] Although method steps may be presented and described herein in a sequential fashion, one or more of the steps shown and described may be omitted, repeated, performed concurrently, and/or performed in a different order than the order shown in the figures and/or described herein. Those skilled in the art will recognize that a wide variety of modifications, alterations, and combinations can be made with respect to the above described examples without departing from the scope of the invention, and that such modifications, alterations, and combinations are to be viewed as being within the ambit of the inventive concept. | A light emitting diode system allows for high current end user LED matrix applications while mitigating internal damage to control circuitry that may be caused by excess current flow. In one example, multiple switches operate in parallel across an LED. When an overvoltage condition is detected in a first switch, a logic circuit determines those switches programmed to operate in parallel and causes them to conduct current. This reduces the amount of current flowing through any one switch and mitigates harm to the device. The parallel configuration of switches may be driven by a single pulse width modulated current. This allows the drive current to be divided between parallel transistors, limiting the damaging effects that can be caused by high currents flowing through the transistors. | 7 |
PRIOR APPLICATION
[0001] This application claims priority from and is a divisional application of U.S. patent application Ser. No. 11/034,527 filed Jan. 12, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Introduction
[0003] This invention relates to an emulsion composition for the formation of an artificial tear film over the ocular surface of the eye capable of providing mechanical lubrication while reducing evaporation of fluid. The composition is also useful for delivering medication to the ocular surface and for treating individuals wearing ocular prostheses such as contact lenses as the composition wets and provides lubrication for both the ocular surface and the surface of the prosthesis. More particularly, the invention relates to emulsion compositions capable of augmenting and maintaining a stable tear film over the ocular surface and/or delivering a medication to said surface without causing substantial blurring of vision nor discomfort. The emulsion is desirably in the form of a meta stable emulsion and is characterized by the use of a surfactant combination suitable for formation such an emulsion and maintaining the integrity of the emulsion during high temperature autoclaving.
[0004] 2. Description of the Prior Art
[0005] It is known in the art that an aqueous tear film extends over the ocular surface and maintains the ocular surface moist and lubricated. It is also known that dehydration of moisture from the eye may result in discomfort. Further, it is known that compositions are available in the market intended for dry eye treatment. Commercially available compositions are primarily aqueous materials that supplement the tear film by adding a film of a water-soluble polymer over the surface of the eye. This film is short lived and provides limited relief.
[0006] The feeling of discomfort resulting from a dry eye condition may include ocular dryness, grittiness, burning, soreness or scratching, dependent upon the subject and the condition of the subject. Proposed causes for dry eye, treatment, and symptoms are described in a compendium of papers edited by Holly, The Preocular Tear Film in Health, Disease, and Contact Lens Wear, The Dry Eye Institute, Lubbock, Tex. 1986; edited by David A. Sullivan, Lacrimal Gland, Tear Film, and Dry Eye Syndromes, 1994, Plenum Press, New York; edited by David A. Sullivan et. al, Lacrimal Gland, Tear Film, and Dry Eye Syndromes 2, 1998, Plenum Press, New York; edited by David A. Sullivan et. al, Lacrimal Gland, Tear Film, and Dry Eye Syndromes 3, Part A and B, 2002, Kluwer Academic/Plenum Publishers, New York incorporated herein by reference for their teachings of the dry eye condition and the treatment thereof.
[0007] The most common treatment for dry eye involves temporary alleviation of dry eye symptoms by topical application of a tear substitute that adds a large volume of liquid to the anterior surface of the eye and related adnexa. Typical commercially available tear substitute compositions comprise water-soluble polymer solutions. Examples of such solutions include saline solutions of polyvinyl alcohol, hydroxypropylmethyl cellulose, or carboxymethyl cellulose. U.S. Pat. No. 4,421,748 teaches an artificial tear composition comprising an aqueous hypotonic solution of lecithin and a viscosity-adjusting agent such as a solution of a soluble cellulose.
[0008] Methods used to quantify the effectiveness of tear substitutes for dry eye treatment solutions have not been standardized, and many methods used to quantify the results obtained using such tear substitute compositions are often inaccurate. For this reason, it is known that reported relief of dry eye symptoms using known tear substitutes varies considerably from subject to subject, and regardless of the method used to quantify relief using a tear substitute, relief often does not exceed several minutes.
[0009] The symptoms associated with dry eye are often exacerbated with subjects using ocular prostheses such as contact lenses. In some cases, contact lens intolerance is caused in part, or in total, by the condition of dry eye and its symptoms. Further, the rate of evaporation from the eye is accelerated by the nature of the contact lens surface and the physical presence of the contact lens results in meniscii formation with additional physical and evaporative effects, even with subjects having an adequate tear film. For many subjects, contact lens intolerance is not overcome by topical application of tear substitutes. Therefore, there is a need for improved compositions and processes for treatment of the dry eye condition and for improving tolerance to ocular prostheses.
[0010] Improved compositions for dry eye treatment are disclosed in U.S. Pat. Nos. 4,914,088; 5,278,151; 5,294,607; 5,578,586, each incorporated herein by reference for its teaching of how to form an oil film over the surface of the eye including compositions used therefor. U.S. Pat. No. 4,914,088 teaches the use of certain charged phospholipids for the treatment of dry eye symptoms. The addition of a charged phospholipid to the eye is believed to assist in replicating the tear film that would naturally occur in the eye. In accordance with the patent, the phospholipid composition, preferably in the form of an aqueous emulsion, is topically applied to the eye where it is believed to disperse over the ocular surface and form a film that replicates a lipid layer that would be formed by the spreading of a naturally occurring lipid secreted principally from the meibomian glands during blinking. Because the phospholipid, when applied to the eye, in one embodiment, carries a net negative charge, it is believed that aligned molecules repel each other preventing complex aggregate formation thereby resulting in a stable phospholipid film. The patent theorizes that the film formed from the charged phospholipid assists in the formation of a barrier film reducing evaporation of the aqueous layer, thereby preserving the tear film. It is also now theorized that the phospholipid also functioned as a surfactant maintaining the emulsion stable.
[0011] The above referenced U.S. Pat. Nos. 5,278,151; 5,294,607; and 5,578,586 disclose further improvements in dry eye treatment. In accordance with the disclosure of said patents, the dry eye treatment composition of U.S. Pat. No. 4,914,088 is improved by the addition of an oil to the eye treatment composition, preferably a non-polar oil. The oil is added to improve the performance of a dry eye treatment composition by increasing the longevity of the tear film formed on the eye as a consequence of the formation of an oil film over the ocular surface that functions as an evaporation barrier—i.e, by providing and/or thickening the dehydration barrier (the oil layer) on the outer surface of the tear film. Thus, the oil increases the efficacy of the dry eye treatment solution and reduces performance variability from subject to subject.
[0012] A preferred embodiment disclosed in the above referenced patents is a dry eye treatment composition comprising a meta stable oil in water emulsion where the water phase includes the charged phospholipid believed to function both as an emulsifier and as a surfactant that assists in spreading of the oil over the eye to form a non-blurring film bonding of the oil to the ocular surface. Preferably, the oil phase comprises a non-polar oil. In accordance with this preferred embodiment, the emulsion is desirably “meta” stable so that when the emulsion is applied to the eye, it will rapidly break and spread over the ocular surface when it first comes into contact with the ocular surface, all as explained in the aforesaid patents.
[0013] The meta stable emulsions of the foregoing patents are formulated whereby the total amount of oil added to the eye preferably does not exceed 25 μl, more preferably varies between about 1 and 10 μl and most preferably varies between about 1 and 5 μl. If the amount of oil added to the eye is in excess of 25 μl, the oil layer on the surface of the eye may be of excessive thickness resulting in formation of oil globules on the surface of the eye. These globules are likely to result in prolonged blurring. To achieve control of the amount of oil added to the eye, the concentration limits of the oil in the emulsion are controlled within reasonable limits. An emulsion containing the oil in a concentration of at least 0.1 percent by weight of the total composition provides some benefits, a preferred concentration is at least 1.0 percent of the weight of the treatment composition, and the most preferred oil content varies between about 2.5 and 12.5 percent by weight of the emulsion.
[0014] Though the use of an oil in water meta stable emulsion having a negatively charged phospholipid as a surfactant provides excellent clinical results for dry eye treatment, there are certain disadvantages associated with their use. For example, the phospholipid component is costly when manufactured to the requirements and tolerances required for use on the eye. In addition, the storage of the phospholipids requires special conditions. Further, the lack of a long history relating to the use of a phospholipid on the eye could raise questions regarding safety and might create possible concerns by regulatory agencies that might require lengthy and costly clinical trials for approval. A further problem involves possible reluctance of companies marketing eye treatment products to deviate from the use of those ingredients having a long history of uneventful use in existing, commercially available treatment products.
[0015] For the foregoing reasons, it is desirable to find one or more surfactants that may be substituted for the charged phospholipids used to form a meta stable oil in water emulsion as disclosed in the aforesaid patents. Though it might appear that simple trial and error could be used to find a suitable surfactant, the task of finding a substitute surfactant is difficult. For example, the replacement surfactant must be acceptable for human use. Many available surfactants are not approved for use on the ocular surface. The replacement surfactant must not cause discomfort to the patient when used in a concentration adequate to form the desired emulsion. Many surfactants may not be added to the eye in suitable concentration without causing stinging. A physiologicall pH of between about 7.0 and 7.8 is required for application to the ocular surface. Many surfactants function as surfactants within a prescribed range of pH, both above and below pH 7. The desired emulsion for treatment of dry eye is preferably meta stable enabling it to rapidly break when applied to the eye. Therefore, the replacement surfactant must enable formation of an emulsion that is stable in manufacture and storage and meta stable and capable of breaking when applied to the ocular surface. The replacement surfactant must be capable of forming an emulsion containing oil in an acceptable concentration as described above to avoid prolonged blurring following application. Finally, the emulsion formed must be sufficiently robust to withstand sterilization at elevated temperatures without breaking, but sufficiently unstable so as to break when applied to the eye. It has been found that many replacement surfactants capable of forming a stable emulsion are incapable of maintaining stability of the emulsion during autoclaving at that temperature required for sterilization if used in a concentration suitable for addition to the eye without causing stinging, or in the alternative, if sufficient to withstand autoclaving, may be so robust that they will not break when applied to the eye.
SUMMARY OF THE INVENTION
[0016] In accordance with the subject invention, it has been found that a preferred meta stable oil in water emulsion suitable for application to the ocular surface for treatment of the eye may be formed using a combination of surfactants as emulsifiers where one surfactant is a physiologically acceptable surfactant capable of forming the desired meta stable emulsion at physiological pH, hereafter the “primary surfactant”, and an additional surfactant, used in combination with the primary surfactant, is a physiologically acceptable surfactant capable of maintaining the emulsion stable during autoclaving at temperatures in excess of 75° C. or higher without preventing the emulsion from breaking when applied to the eye, hereafter the “secondary surfactant”.
[0017] The preferred primary surfactant comprises any one or more physiologically acceptable surfactants capable of forming a meta stable oil in water emulsion at pH between about 7.0 and 7.8 without causing discomfort to the patient when used in a concentration adequate to form the desired emulsion having an oil phase in a concentration of from 1.0 percent by weight up to that amount below that which would causes blurring. The term “meta stable emulsion” means one that is stable in storage but breaks rapidly when instilled onto the ocular surface as described in the above referenced U.S. Pat. Nos. 5,278,151; 5,294,607; 5,578,586. The primary surfactant may be identified by routine experimentation using procedures described below. Surprisingly, other than the phospholipids, the subject of the above referenced patents, no single surfactant has been found capable of use as a sole surfactant to form a meta stable emulsion meeting the guidelines set forth herein though it should be understood that such an emulsion might be formed using a single surfactant in high a concentration whereby the patient is likely to experience stinging when the emulsion is added to the eye.
[0018] The preferred secondary surfactant is one or more physiologically acceptable surfactants that is used in conjunction with the primary surfactant which does not alter the meta stable form of the emulsion and does not cause discomfort to the patient at efficacious concentration, while stabilizing the emulsion by preventing decomposition at the elevated temperatures required for autoclaving, typically at temperatures in excess of 75° C. and desirably at temperatures at or in excess of 100° C. Though not mandatory for all secondary surfactants, as a guideline only, the secondary surfactant desirably has a relatively long chain with a minimum of 6 hydrophilic groups and an HLB of 9 or more, and preferably an HLB ranging between 12 and 20, and a lipophilic group that is small in relation to the hydrophilic group and preferably, the same or similar in structure to the lipophilic group of the primary surfactant.
[0019] From the literature, it would be expected that one skilled in the art would select a surfactant combination having an arithmetic mean HLB of between about 8 and 14 and more typically, between about 10 and 12 for formation of an oil in water emulsion of the type described herein. The arithmetic mean is determined based upon the HLB of the individual surfactants selected and the concentration of each surfactant used. Unexpectedly, an arithmetic HLB of between 8 and 14 is not required for purposes of the present invention as will be demonstrated below.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] The treatment composition of the invention is an oil in water emulsion having an aqueous phase, an oil phase, and a surfactant combination used for the dual purpose of stabilizing the emulsion and spreading the emulsion over the ocular surface following its application to the eye. The surfactant combination comprises a primary surfactant and secondary surfactant and is one that enables formation of an emulsion that is stable in manufacture and during storage, but desirably meta stable when applied to the ocular surface—i.e., one that rapidly differentiates when applied to the eye whereby a non blurring film of oil is rapidly formed over the ocular surface. A stable emulsion during manufacture and storage is one that may separate into separate phases during standing, but can be reconstituted by simple shaking. An unstable emulsion is one that breaks typically forming an oil film or slick that cannot be eliminated by simple shaking.
[0021] A meta stable emulsion during use is desirable for purposes of this invention. Though useable for alleviation of dry eye symptoms, a stable emulsion, as opposed to a meta stable emulsion, will not differentiate rapidly when applied to the ocular surface. This is undesirable for the following reasons. An emulsion is typically optically opaque due to the presence of two distinct phases. Therefore, an opaque emulsion over the surface of the eye is likely to cause blurring. The duration of blur is dependent upon the time required for the emulsion to differentiate and form separate layers replicating a tear film. In addition, the emulsion is most easily added to the eye as a standard drop from an eyedropper. The eye is capable of holding a limited volume of fluid—a volume that is less than 25 μl. A volume of 25 μl is substantially less than the volume of a standard drop. Therefore, if the emulsion is stable and fails to differentiate rapidly following application to the eye, excess emulsion will be discharged from the eye during blinking. Discharge of the emulsion from the eye will result in discharge of efficacious components of the treatment solution from the eye before a long lasting tear film can be formed. For this reason, efficacious components may not be available in sufficient quantity to form the desired tear film. Consequently, though a stable emulsion might alleviate the symptoms of dry eye for a limited period of time, it is a lesser preferred embodiment of the invention.
[0022] A meta stable emulsion, as the term is used herein, is one that is either stable in storage, or differentiated into two separate layers, but is readily reconstituted by simple shaking prior to use. When a meta stable emulsion is added to the eye as a standard drop, it quickly differentiates permitting rapid formation of an oil film over the corneal surface without excessive oil discharge by blinking. Preferably, the emulsion will differentiate within about 5 blinks following application to the eye, more preferably in a time of less than about 30 seconds. Blurring may occur during the time required to move the bulk of the excess liquid to the canthi and discharge the same from the eye. During and following differentiation of the emulsion, the formation of the oil film is assisted by use of the surfactant combination which serves to help form the emulsion and facilitate the spread the oil over the surface of the eye as the emulsion breaks. Consequently, a meta stable emulsion is the preferred embodiment of this invention.
[0023] The surfactant combination used to form a meta stable emulsion must be carefully selected and must meet the following criteria:
a. the surfactant combination must enable formation of an emulsion having long term stability, especially when exposed to the high temperatures of autoclaving needed to sterilize the formulation during manufacture, while permitting rapid phase differentiation when applied to the surface of the eye; b. each component of the surfactant combination must be compatible with other components of the emulsion composition and permit formation of the emulsion at the physiological pH of between about 6.5 and 7.8 and preferably, at pH of between 7.2 and 7.5; and c. each component of the surfactant combination must be pharmaceutically acceptable for use on the eye and must be compatible with the eye—i.e., each should be non-toxic and should not cause discomfort such as stinging in the concentrations used.
[0027] As described above, the surfactants used to form the emulsions of the invention comprise a combination of a primary surfactant and a secondary surfactant.
[0028] The primary surfactant is any one or more pharmaceutically acceptable surfactants that meets the above criteria and desirably forms a meta stable emulsion by itself or in combination with the secondary surfactant, but differs in chemical structure from the secondary surfactant. The literature is replete with thousands of surfactants having a variety of chemical structures described as useful for the formation and stabilization of an oil in water emulsion. To provide an exhaustive list of representative surfactants capable of functioning as a primary surfactant for purposes of the subject invention would be laborious and would omit many useful candidate materials. Therefore, in addition to the representative examples given below, a procedure is given intended to enable one skilled in the art to determine if a given surfactant may be used as a primary surfactant in accordance with the preferred embodiment of the subject invention. This procedure involves the following steps:
a. select a surfactant approved for use on the ocular surface within a useful concentration range as given below; b. from the literature or by testing, determine if the surfactant is capable of forming an emulsion with the oil and water components at physiological pH; c. prepare an emulsion having the concentration of emulsion components given below and determine if the emulsion is stable during storage, a minimum of three months under normal storage conditions, or capable of being reconstituted by simple shaking; and d. apply the emulsion to the ocular surface and determine if the emulsion breaks on the ocular surface within a minute or less, preferably in less than 30 seconds or 5 blinks.
[0033] Representative examples of primary surfactants meeting the criteria given above include ionic and non-ionic surfactants but non-ionic surfactants are preferred as they are less prone to cause stinging when applied to the eye. Specific examples of the nonionic surfactant include alkyl ethers such as polyoxyethylene octyl ether, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether and polyoxyethylene oleyl ether; alkyl phenyl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether; alkylesters such as polyoxyethylene laurate, polyoxyethylene stearate and polyoxyethylene oleate; alkylamines such as polyoxyethylene laurylamino ether, polyoxyethylene stearylamino ether, polyoxyethylene oleylamino ether, polyoxyethylene soybean aminoether and polyoxyethylene beef tallow aminoether; alkylamides such as polyoxyethylene lauric amide, polyoxyethylene stearic amide and polyoxyethyleneoleic amide; vegetable oil ethers such as polyoxyethylene castor oil ether and polyoxyethylene rapeseed oil ether; alkanol amides such as lauric acid diethanol amide, stearic acid diethanol amide and oleic acid diethanol amide; and sorbitan ester ethers such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan monooleate. Of the above, polyoxyethylene stearates are preferred. Additional suitable surfactants can be found by reference to a standard text on surfactants such as those described in Ash and Ash, Encyclopedia of Surfactants, Chemical Publishing Company, New York, 1985; McCutcheon's Emulsifiers and Detergents, North American Edition, McCutcheon Publishing Company, Glen Rock, N.J., 2000; and Remington: The Science and Practice of Pharmacy, Nineteenth Edition, Vol. 1 at p. 251 coupled with the use of the procedures set forth above.
[0034] The secondary surfactant is one or more surfactants meeting the above criteria and in addition, enables the emulsion to withstand autoclaving without significant degradation of the emulsion. The secondary surfactant desirably has a relatively small lipophilic group and a long chain hydrophilic group with a minimum of 6 repeating hydrophilic groups. More preferably, the secondary surfactant has an HLB of 9 or more, and most preferably, an HLB ranging between 12 and 20, a hydrophilic group of at least 9 repeating hydrophilic groups, most preferably at least 9 ethylene oxide groups or isopropyl oxide groups, and a relatively small lipophilic group that is the same or similar in structure to the lipophilic group of the primary surfactant. Exemplary nonionic surfactants include, but are not limited to the Octoxynol-n series of the formula C 8 H 17 C 6 H 4 (OCH 2 CH 2 )OH n where n is between 5 and 70 and preferably between 30 and 50, the nonoxynol-n series of the formula C 9 H 19 C 6 H 4 (OCH 2 CH 2 )OH p where p is between 5 and 40 and preferably between 15 and 30, and polyoxyethylene C 12-22 alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether or polyoxyethylene oleyl ether. Most preferred secondary surfactants are the Octoxynol series of surfactants having between 30 and 50 ethylene oxide groups. Numerous other surfactants having an HLB value of greater than about 9 and meeting the above criteria are listed in Ash and Ash, McCutcheons, and Remington, supra.
[0035] The concentration of the surfactant combination used to form the emulsion may vary within wide limits. A treatment composition containing the surfactant combination in an amount as low as 0.01 weight percent of the total composition provides some benefit. A concentration of surfactant combination varying between 0.05 to 5.0 percent of the total composition is a clinically practical concentration range for purposes of the invention provided that the surfactant does not cause patient discomfort when used at the higher concentrations. Most preferably, the concentration of the combination varies between about 0.25 and 2.5 percent by weight of the total composition. It should be understood that with many surfactants, as concentration increases, the likelihood of physical discomfort—i.e., stinging, of the emulsion on the eye increases. Thus, if significant stinging occurs when the emulsion is applied to the ocular surface, it is likely that the concentration of surfactant is too high.
[0036] The ratio of the primary surfactant to the secondary surfactant may vary within relatively broad limits—for example, between 0.2 to 1.0 to 1.0 to 0.2 primary to secondary surfactant. A more preferred range varies between 0.5 to 1.0 and 1.0 to 0.5. Most preferably, the primary surfactant is used in slightly larger concentration than the secondary surfactant and the most preferred ratio varies between 1.0 to about 0.75.
[0037] The emulsions of the invention comprise an oil in water emulsion. The oil used to form the emulsion may be derived from animals, plants, nuts, petroleum, etc. Those derived from animals, plant seeds, and nuts are similar to fats and are primarily glycerides or fatty acids and consequently, contain a significant number of acid and/or ester groups rendering the same polar and lesser preferred for purposes of the invention. Alternatively, oils derived from petroleum are usually aliphatic or aromatic hydrocarbons that are essentially free of polar substitution and therefore suitable for purposes of the present invention provided the oil is refined so as to be compatible with human tissue such as the ocular surface. Preferably, the oil is a linear hydrocarbon oil having from 10 to 50 carbon atoms and more preferably, the oil is a saturated n-alkane or isoalkane hydrocarbon having from 14 to 26 carbon atoms. Unsaturated alkene hydrocarbons may be used but are less chemically stable. Aromatic oils are lesser preferred because it is known that aromatic compounds are for the most part unsuitable for application to the ocular surface. Mineral oil is the most preferred oil for purposes of this invention.
[0038] The oil component within the emulsion may vary within reasonable limits provided the amount of oil retained on the eye following its application to the eye is within controlled volumes and does not exceed 25 μl, more preferably varies between about 1 and 10 μl and most preferably varies between about 1 and 5 μl. If the amount of oil added to the eye is in excess of 25 μl, the oil layer on the surface of the eye may be of excessive thickness and resulting in prolonged blurring. A treatment composition containing the oil in a concentration of at least 0.1 percent by weight of the total composition provides some benefits. A preferred concentration for the oil is at least 1.0 percent of the weight of the treatment composition. Preferably, the oil content of the treatment solution varies between about 2.5 and 12.5 percent by weight of the composition.
[0039] Other additives may be present in the treatment composition. Such materials include minor amounts of neutral lipids and oils such as one or more triglycerides, cholesterol esters, the natural waxes and cholesterol; high molecular weight isoprenoids; stabilizers, additional surfactants; preservatives; pH adjusters to provide a composition preferably having a pH between about 6.5 and 7.8 and most preferably, between about 7.2 and 7.5; salt, glycerol or sugar in sufficient concentration to form an isotonic or mildly hypotonic composition; etc., all as would be obvious to those skilled in the art.
[0040] Another useful class of additives comprises medications. As a consequence of the long term stability of the oil film formed over the surface of the eye using the emulsion compositions of the invention, prolonged and improved delivery of the medication to the eye results due to increased contact time of the medication on the eye. Medications suitable for delivery to the eye using the film forming compositions of the invention are those soluble in either the aqueous or oil phase of the composition though it is preferable that the medication be soluble in the oil phase. Illustrative medications include antibiotics, antiviral agents, anti-inflammatory agents and antiglaucoma agents such as illustrated in part in published European Patent Application No. 0 092 453 published Oct. 26, 1983, sections 5.3.1 and 5.3.2, incorporated herein by reference.
[0041] Any additional additives are added to the emulsion are added prior to formation of the emulsion using simple mixing techniques. The concentration of the additive is dependent upon the specific additive, and preferably, total additive content in addition to the surfactant and the oil are at a maximum concentration level whereby the total weight of the organics in the oil phase does not exceed 15 percent of the total weight of the emulsion.
[0042] In accordance with the invention, the emulsions may be made in accordance with standard procedures. Desirably, a commercial homogenizer is used to form the emulsion as equipment of this nature enhances the stability of the emulsion during transportation and storage. The use of commercial homogenizers for the formation of emulsions is within the skill of the art.
[0043] The emulsions of the invention are also desirably used with subjects requiring ocular prostheses. In this instance, the treatment composition enhances the tear film layer and lubricates the boundary between the prosthesis and the ocular surface. When used with an ocular prosthesis, the treatment composition may be applied to the inner or both the inner and outer surfaces of the prostheses prior to insertion of the same into the eye. Regardless of how added, the amount available to form the oil layer should be within the limits set forth above.
[0044] The invention will be better understood by reference to the examples that follow. In the examples, the thickness of the lipid layer of a tear film formed over the ocular surface is evaluated by projecting a light source onto the ocular surface while viewing the reflected images from the light source on a video screen. The light source and its location is one that illuminates a surface area on the ocular surface of approximately 10 mm 2 . Interference patterns are formed, the color(s) of which are indicative of the thickness of the oil layer. The color of the waves is correlated with a protocol of known film thickness. In this way, the tear film can be evaluated over a period of real time and rated in accordance with the following scale:
[0000]
Rating
Film Characteristics
Quality
A
Colored waves - particularly greens
Excellent
and blues. Waves extend from lower
to above the lower pupillary border.
Film thickness is excess of 170 nm.
B
Colored waves - reds, browns, yellows,
Good
but no blues. Waves extend from lower
lid to above the pupillary border.
Film thickness of approximately 90 nm.
C
Colored waves - only yellow is present.
Good
Waves extend form lower lid to lower
pupillary border. Film thickness of
approximately 90 nm.
D
Waves visible but no color present
Fair
or no color other than grayish white.
Waves extend from lower lid to lower
pupillary border. Film thickness of
less than 90 nm.
E
No waves and no color. An absence of
Poor
any observable tear film movement.
Film thickness of less than 70 nm.
[0045] Further details pertaining to experimental procedure can be found in the above referenced U.S. Pat. Nos. 5,278,151; 5,294,607; and 5,578,586.
[0046] The data presented in the examples was obtained using individuals with baseline lipid layers of C rating or less. The data illustrates the resultant change in lipid layer characteristics from the baseline finding to the finding for lipid characteristics after the application of a standard eye drop of the test formulation to the eye. A desirable result is for improvement in lipid layer characteristics, evidenced by an increase in the alphabetical grade, with A being the most desirable, and F being the least desirable. The evaluations were performed 5 minutes after the instillation of the test formulations.
[0047] The first two examples illustrate that emulsions may be formed using surfactants having properties and HLBs suggesting suitability for formation of stable oil in water emulsions, but illustrate that the emulsions so formed are unstable at autoclaving temperatures and therefore unsuitable for dry eye treatment. Example 3 illustrates that a surfactant that might be suitable for formation of an emulsion having properties meeting the objectives of this invention is unsuitable as it causes discomfort to the patient when added to the eye. Examples 4 and 5 illustrate that primary surfactants unsuitable for formation of a dry eye emulsion can be made functional when used in combination with the secondary surfactants of the invention regardless of the arithmetic HLB.
Example 1
[0048] This example illustrates that various surfactant combinations may be used that meet certain of the guidelines set forth above, especially those relating to HLB, but still fail to provide a meta stable emulsion able to withstand the elevated temperatures required for sterilization of the formulation.
[0049] A mixture of Myrj-52, a polyoxyethylene (40) stearate, and glycerol monostearate (GMS), were used as primary surfactants to form a dry eye treatment emulsion with mineral oil as the oil phase. Myrj-52 has a high HLB value (15-16.9) and is water-soluble. Glycerol monostearate (GMS NF) has a low HLB value (3-5) and is therefore oil soluble suggesting that the combination should form a suitable oil in water emulsion. These surfactants have an identical lipophilic group (stearate) but different hydrophilic groups, and thus will have different physical behavior in terms of partitioning into the oil or water phases as suggested by the difference in the HLB value of the two surfactants.
[0050] This combination of surfactants was evaluated by formation of 11 emulsions utilizing 5.5% (±0.3%) of Drakeol-35, a commercially available mineral oil at two different total surfactant concentrations −0.15% and 0.30%. The non-polar oil phase of Drakeol-35 mineral oil and the aqueous phase of 0.67% NaCl and 0.05% of anhydrous Na 2 HPO 4 were common to all 11 of these formulations; the pH was adjusted with diluted HCl as required. The relative concentration of the two individual surfactants was varied to evaluate the effect of the average HLB on emulsion quality as shown in Table 1. Emulsification of the 11 formulations was performed using a commercial homogenizer (PRO250) from Proscientific, Inc., with a ¾ horsepower motor which drove a 30 mm rotor-stator generator, by combining all of the reactants into one vessel and raising the temperature to approximately 90° C. Table 1 provides the formulations and the compositions (in grams) for the 11 test formulations utilizing the Myrj-52 and GMS primary surfactant systems.
[0000]
TABLE 1
gm Myrj-52
gm GMS
gm Drakeol 35
Surfactant Content
0.094
0.065
5.700
0.15%
0.102
0.054
5.334
0.15%
0.112
0.042
5.508
0.15%
0.127
0.037
5.404
0.15%
0.130
0.030
5.284
0.15%
0.139
0.020
5.284
0.15%
0.298
0.017
5.309
0.30%
0.279
0.042
5.300
0.30%
0.258
0.065
5.283
0.30%
0.233
0.091
5.308
0.31%
0.207
0.108
5.303
0.30%
Footnotes
1. Myrj-52 is polyoxyethylene (40) stearate
2. Glyceryl monostearate (GMS) is the glycerol ester of stearic acid
3. Drakeol refers to a series of NF mineral oils available from Penreco Co. of Butler, PA. The numeral following the letters represents the average molecular weight of the oil, and is an indication of the viscosity of the fluid.
Results
[0051] The formulations of Table 1 produced emulsions which all met the first criterion of separation when at rest for several minutes. They also appeared to meet the second criterion of the emulsion returning to its original dispersed form after simple agitation. However, after periods of 60 minutes to 1 day, some of the oil phase in the formulations with the higher HLB values evidenced significant oil breakout, where the individual oil droplets were broken, resulting in the formation of an oil film on the surface.
[0052] The formulations with the lower HLB values provided emulsions that did not evidence the oil film after similar periods of time. However, when agitated with mechanical shaking to simulate transportation effects, the oil film was visible on the surface within a time period that precluded a commercially viable product.
[0053] In general, an increasing value of the calculated HLB produced poorer quality emulsions upon standing or upon agitation. However, no formulation in Table 1 was found to be adequate because of the degradation of the individual oil droplets and the subsequent formation of a surface oil layer. Further, microscopic studies and photographs of these formulae taken before and after both autoclaving and shaking demonstrated that the oil droplets were degraded either by being subjected to autoclaving at 121° C. or by shaking on the Platform Rocker Shaker by Vari-Mix for less than one day.
[0054] The above example illustrates that for the materials of this example, HLB values alone proved to be an unreliable parameter of complex formulation issues in the development of the intended dry eye treatment composition. While HLB values are generally useful as a formulation development guide, it was obvious that further considerations are required for the development of a dry eye treatment composition suitable for purposes of this invention.
[0055] Resolution of the above described problem would likely require significantly higher surfactant concentrations but it was known that increasing the concentration of Myrj-52% would result in ocular discomfort—i.e. significant stinging. For this reason, the formulation was not evaluated clinically.
Example 2
[0056] Polysorbate-80 (trade name Tween-80), a stearyl ether of a polysorbate, was evaluated as a sole primary surfactant for forming a dry eye treatment emulsion utilizing a total concentration of 7.0% of a mineral oil mixture of Draekol-15 and Draekol-35. In this study, Polysorbate-80 concentrations of 0.2%, 1.0%, and 1.5% were utilized in the base formula as displayed in Table 2 as formulae C1 through C6. These formulations were prepared with and without disodium EDTA. Emulsification of the 6 formulations was carried out with a commercial homogenizer (PRO250) from Proscientific, Inc., using a ¾ horsepower motor that drove a 30 mm rotor-stator generator, by combining all of the reactants into one vessel and raising the temperature to approximately 90° C. Table 2 provides the formulations and the compositions (in grams) for the 6 test formulations utilizing Tween-80 as the sole surfactant,
[0000]
TABLE 2
formulae
C1
C1
C3
C3
C5
C6
D-15
2.07
2.07
2.02
2.02
2.02
2.03
D-35
5.17
5.17
5.04
5.04
5.05
5.07
Polysorbate-80
0.20
0.20
1.00
1.00
1.50
1.51
NaCl
0.67
0.67
0.67
0.67
0.67
0.67
Na 2 HPO 4 (anh.)
0.05
0.05
0.05
0.05
0.05
0.05
NaH 2 PO 4 •2H 2 O
0.02
0.02
0.02
0.02
0.02
0.03
EDTA
0.02
0.02
0.02
0.02
0.02
0.00
Water
100
100
100
100
100
100
Footnotes
1. Drakeol refers to a series of NF mineral oils available from Penreco Co. of Butler, PA. The numeral following the letters represents the average molecular weight of the oil, and is an indication of the viscosity of the fluid
2. Polysorbate-80 is a stearyl ether of a polysorbate and is sold under the tradename Tween-80 by ICI (now known as Uniqema, New Castle, DE) in Wilmington, DE.
Results
[0057] The six emulsions prepared using Polysorbate-80 as a sole primary surfactant were found to meet the first criterion of providing appropriate separation of the oil and aqueous phases upon resting in the container for several minutes. The second criterion of reconstitution by simple product agitation was also met. However, these formulae failed to meet the third criterion because all were destabilized (as evidenced by surface oil film formation) when agitated for short periods of time on the laboratory shaker or when autoclaved for 30 minutes at 121° C. Increased Polysorbate-80 content in the formulae to 1.50 decreased oil droplet instability, but still failed to meet the third criterion. The failure to meet the third criterion was confirmed in post autoclaved and post shaken samples, in that that the surface oil film formed by droplet coalescence prevented the reconstitution of the emulsion by simple shaking as required by the second criterion.
[0058] These formulae thus did not meet the requirements for the desired eye treatment solution. It was found that when using only Polysorbate-80 as a sole primary surfactant, a higher concentration of Polysorbate-80 was required with the following undesirable results: (1) the emulsion was not autoclave stable, (2) the higher concentration of the Polysorbate-80 led to stinging on the eye and (3) the higher concentration of the Polysorbate-80 degraded the performance of the meta stable emulsion on the eye. Thus, thee performance of these samples failed by a wide margin to meet the criterion of maintaining the original emulsion characteristics after agitation for a period of time. Therefore, the use of Polysorbate-80 as a sole surfactant for the non-polar oil formula was judged inadequate and was not evaluated clinically.
Example 3
[0059] Though this example does not illustrate the formation of an emulsion, it does illustrate the basis for rejection of a primary surfactant that would otherwise appear to be suitable for formation of an oil in water emulsion.
[0060] The example describes the evaluation of Span 20, a highly viscous water insoluble sorbitan monolaurate, for suitability as a surfactant system for use on the eye. The HLB of 8.6 of this surfactant, and its reported use in ophthalmic products suggested that it would be a suitable surfactant for formation of an oil in water emulsion using mineral oil.
[0061] Five concentrations of Span 20, from 0.05% to 1.00% WV were prepared in a buffered normal saline vehicle for evaluation of comfort on the eye. The vehicle used for all formulations was Unisol 4, a buffered saline solution marketed by Alcon Laboratories, Fort Worth, Tex. Unisol 4 had previously been studied and found to be the most comfortable normal saline product for use on the ocular surface. It was therefore used as a vehicle for the test formulations, and was also used as a control.
[0062] A drop of each of the 5 test formulations was placed on to the ocular surfaces of each subject, utilizing a 15 ml dropper container that delivered a drop of 40 μl to the ocular surface. The subject was asked to describe the sensation as one of: pleasant, neutral, slight sting, moderate sting, or severe sting.
Results
[0063] The results obtained with 6 subjects, all of whom evaluated each of the test formulation on two different days are summarized in Table 3.
[0000]
TABLE 3
Formulation
Results
S477 (Control, Unisol 4)
Pleasant to neutral
S478 (0.05% Span 20)
Neutral to slight sting
S479 (0.10% Span 20)
Neutral to slight sting
S480 (0.20% Span 20)
Slight to moderate sting
S481 (0.40% Span 20)
Moderate sting
S482 (1.00% Span 20)
Moderate to severe sting
Footnote
1. Span 20 is a highly viscous water insoluble sorbitan monolaurate sold under the tradename Span 20 by ICI (now known as Uniqema, New Castle, DE) in Wilmington, DE.
[0064] In view of the sting when applied to the eye and ocular surfaces, even in concentrations ≦0.10%, the use of Span 20 was rejected as a suitable surfactant for an eye treatment composition.
Example 4
[0065] This example illustrates that Polysorbate-80 found unsatisfactory for purposes of this invention in Example 2 can be made suitable by combination with a secondary surfactant, in this case Octoxynol-40.
[0066] The example determines the optimum ratio of a mixed surfactant system comprising Polysorbate-80 as a primary and Octoxynol-40 as a secondary surfactant to maximize the stability of the oil/water interface in the ocular emulsion systems. Formulae utilizing 2.4% Drakeol-15 and 4.8% Drakeol-35 with both Octoxynol-40 and Polysorbate-80 were evaluated at different concentrations. Octoxynol-40 has an HLB of 19 and Polysorbate-80 has an HLB of 15. The two surfactants combined will yield an arithmetic HLB above the HLB believed suitable for formation of a stable oil in water emulsion. The samples were made both with and without disodium EDTA, keeping the concentrations of the other additives at the levels required for eye treatment compositions. The emulsification of the four formulations prepared was carried out with a commercial homogenizer (PRO250) from Proscientific, Inc., using a ¾ horsepower motor which drove a 30 mm rotor-stator generator, by combining all of the reactants into one vessel and raising the temperature to approximately 60° C. Table 4 sets forth the formulations and the compositions (in grams) for the 4 test formulations utilizing the Octoxynol-40 and Polysorbate-80 surfactant systems.
[0000]
TABLE 4
Formulae
D1 (AD1)
D2 (AD2)
D3 (AD3)
D4 (AD4)
D-15
2.42
2.51
2.41
2.31
D-35
4.83
4.85
4.86
4.84
Octoxynol-40
1.12
1.12
0.63
0.63
Polysorbate-80
0.38
0.38
0.90
0.91
NaCl
0.67
0.67
0.67
0.67
Na 2 HPO 4 (anh.)
0.05
0.05
0.05
0.05
NaH 2 PO 4 •2H 2 O
0.03
0.02
0.02
0.03
EDTA
0
0.02
0.02
0
Water
100
100
100
100
Footnotes
1. Drakeol refers to a series of NF mineral oils available from Penreco Co. of Butler, PA. The numeral following the letters represents the average molecular weight of the oil, and is an indication of the viscosity of the fluid.
2. Octoxynol-40 is polyethylene glycol (40) p-isooctylphenyl ether sold under the tradename Synperonic OP-40 by ICI (now known as Uniqema, New Castle, DE) in Wilmington, DE.
3. Polysorbate-80 is a stearyl ether of a polysorbate sold under the tradename Tween-80 by ICI (now known as Uniqema, New Castle, DE) in Wilmington, DE.
Results
[0067] All 4 formulations met the three pre-clinical criteria of proper separation, reconstitution of the emulsion by gentle shaking and maintaining the original emulsion characteristics when agitated for a period of time of at least 72 hours on the laboratory Platform Rocker Shaker by Vari-Mix, or when autoclaved for 30 minutes at 121° C.
[0068] Microscopic studies and photographs of the samples-before and after autoclaving and shaking demonstrated that the oil droplets were not degraded by being subjected to autoclaving at 121° C., or by shaking on the Platform Rocker Shaker by Vari-Mix for 288 hours.
[0069] Since this formulation of non-polar oil with the surfactant system of Octoxynol-40 and Polysorbate-80 satisfied the pre-clinical criteria, formulae D1 and D3 were evaluated clinically and were found to adequately augment and restore the lipid layer thickness. The results of the clinical evaluations of formulations D1 and D4 are given in the following table:
[0000]
Rating before
Rating after
Patient Number
Formulation
treatment
treatment
1
D1
C
A
2
D1
D
B
3
D1
D
A
4
D1
D
B
5
D1
C
A
6
D1
C
B
7
D1
C
A
8
D4
D
B
9
D4
D
C
10
D4
D
B
11
D4
D
A
12
D4
C
A
13
D4
C
A
14
D4
C
A
[0070] The clinical evaluations of patient numbers 1 to 14 indicated that the surfactant system of Octoxynol-40 and Polysorbate-80 were efficacious in forming and restoring a lipid layer of improved characteristics and that both formulations were essentially equally effective. The subjective sensation realized with both formulations was evaluated as comfortable, and without any form of adverse sensation. The studies of example 3 indicated that the addition of the surfactant Octoxynol-40 as a second surfactant in combination with Polysorbate-80 satisfied the criteria for a dry eye treatment composition.
Example 5
[0071] This study was directed to determining the optimal concentrations of the mixed primary and secondary surfactant system of Polysorbate-80 (Tween-80) and Octoxynol-40 for an optimal dry eye treatment formulation.
[0072] Six formulations were prepared. Each was formed using a commercial homogenizer (PRO250) from Proscientific, Inc., using a ¾ horsepower motor which drove a 30 mm rotor-stator generator, by combining all of the reactants into one vessel and raising the temperature to approximately 60° C. Table 5 illustrates 6 formulations, where the concentration of Polysorbate-80 is held constant at 0.40%, while the concentration of Octoxynol-40 is varied at 0.30%, 0.60% and 1.20% surfactant levels. The 0.40% Polysorbate-80 concentration was chosen from the result of prior experiments that established that this concentration, when used with higher levels of Octoxynol-40, met the pre-clinical requirements, while lower concentrations of Polysorbate-80 had resulted in minimal but detectable oil droplet degradation after being subjected to autoclaving at 121° C., or by shaking on the Platform Rocker Shaker by Vari-Mix for periods of time from 3 days to 288 hours. It was also considered desirable to utilize the lowest concentrations of both Polysorbate-80 and Octoxynol-40 for a dry eye treatment composition, while meeting the previously described requirements, since the sensitivity of the ocular surface cells and the immune response of the eye can be expected to increase with increasing concentration to any compound placed on the eye. These phenomena may also be exacerbated in dry eye states, since the surface epithelial cells are frequently compromised by the desiccation and lack of lubrication accompanying dry eye states. Table 5 provides the formulations and the compositions (in grams) for the 6 test formulations:
[0000]
TABLE 5
Formulae
F1
F2
G1
G2
H1
H2
Polysorbate-80
0.41
0.41
0.40
0.40
0.40
0.40
Octoxynol-40
1.21
1.21
0.60
0.60
0.30
0.30
EDTA•2H 2 0
0.02
0.02
0.02
0.02
0.02
0.02
NaHPO 4
0.05
0.05
0.05
0.05
0.05
0.05
NaH 2 PO 4 •2H 2 0
0.02
0.02
0.02
0.02
0.02
0.02
NaCl
0.67
0.67
0.67
0.67
0.67
0.67
H 2 0
100
100
100
100
100
100
Drakeol-15
2.17
2.16
2.14
2.15
2.12
2.13
Drakeol-35
5.42
5.41
5.36
5.38
5.31
5.33
P/O
0.5
0.5
1.0
1.0
2.0
2.0
rpm
4050
10000
4050
10000
4050
10000
Footnotes
1. Polysorbate-80 is a stearyl ether of a polysorbate sold under the tradename Tween-80 by ICI (now known as Uniqema, New Castle, DE) in Wilmington, DE.
2. Octoxynol-40 is polyethylene glycol (40) p-isooctylphenyl ether sold under the tradename Synperonic OP-40 by ICI (now known as Uniqema, New Castle, DE) in Wilmington, DE.
3. Drakeol refers to a series of NF mineral oils available from Penreco Co. of Butler, PA. The numeral following the letters represents the average molecular weight of the oil, and is an indication of the viscosity.
4. P/O is the molar ratio of the Polysorbate-80 to Octoxynol-40 components.
5. RPM is the speed of the homogenization unit.
[0073] The lowest concentration of 0.30 grams Octoxynol-40 with 0.40 grams Polysorbate-80 was found to optimally satisfy the 3 criteria. The low surfactant concentration is desirable due to the possibility of irritancy of ocular tissue, where the sensitivity to a compound placed on the eye can be expected to increase with increasing concentration. | This invention relates to an emulsion composition for the formation of an artificial tear film over the ocular surface of the eye capable of providing mechanical lubrication for the ocular surface while reducing evaporation of fluid therefrom. The emulsion is desirably in the form of a meta stable emulsion and is characterized by the use of a surfactant comprising a combination of a primary and secondary surfactant where the primary surfactant permits formation of the emulsion and the secondary surfactant permits autoclaving of the surfactant. The invention also includes a method for the formation of such an emulsion. | 0 |
TECHNICAL FIELD
[0001] The present invention relates to a thermal disconnect for removing mechanical connection between a prime mover and a load in response to overheating of the load.
BACKGROUND OF THE INVENTION
[0002] It is known to run devices such as generators, constant speed drive mechanisms, and pumps from shafts or spools of prime movers, such as, for example, gas turbine aeronautical engines. Although the load device should be reliable, there is always a possibility that it will experience abnormal operating conditions or will enter a failure mode wherein damage to the load may occur, with the possibility that such damage may result in abnormally high torques being required from the prime mover, possibly to the extent that its integrity will be compromised.
[0003] U.S. Pat. No. 5,103,949 discloses a disconnection device in which a drive shaft carries a threaded portion and a plunger is arranged to move in from the side of the drive shaft to engage the threaded portion, thereby causing the screwing action between the plunger and the threaded portion to displace the shaft axially such that it becomes disconnected from a prime mover.
[0004] U.S. Pat. No. 4,042,088 similarly has a drive shaft which engages a prime mover via a castellated connection region. The drive shaft also carries a helically threaded portion and a disconnect plunger is arranged to move in from the side of the drive shaft to engage the threaded portion to cause the shaft to move axially so as to disconnect the shaft from the prime mover.
[0005] U.S. Pat. No. 4,989,707 discloses a similar arrangement in which a element moves in from the side of a drive interface between input and output shafts in order to engage a threaded portion of a ring in order to cause disconnection between the shafts.
[0006] Each of these prior art arrangements suffers from the problem that the shafts will, in general, be rotating rapidly and that the teeth on the control element which moves radially inward to engage the screw thread must engage the thread rapidly before they become damaged or sheared off.
[0007] U.S. Pat. No. 4,086,991 discloses a disconnect coupling in which helical splines are used to connect a coupling shaft to a driven member so as to transmit torque to the driven member. The helical splines are carried on an axially movable shaft and are arranged such that the transmission of torque to the driven member acts to urge the coupling shaft and driven member to move to a disengaged position. In normal use, this movement to a disengaged position is inhibited by the provision of a fusible element, such as a eutectic pellet. Such pellets are generally of a soft material and the crushing of the pellet under a compressive load is a well recognised problem, see for example, U.S. Pat. No. 4,271,947 wherein the pellet is manufactured with wire strands therein in order to give it additional mechanical strength. Because of the use of helical splines in U.S. Pat. No. 4,086,991 the crushing force acting on the eutectic pellet varies as a function of the torque transmitted through the disconnect coupling. In particular, the pellet must be able to withstand the crushing load at full torque transfer without suffering deformation. This increase in material in the pellet means that the pellet has an increased mass and thermal capacity, and as such the rate at which the pellet warms is reduced, thereby leading to a potential slowing of the decoupling mechanism. Another problem with the system described in U.S. Pat. No. 4,086,991 is that decoupling between the shaft and the load may not occur when the shaft is lightly loaded. This is significant since the load may be a generator and it is conceivable that the generator itself may not fail, but that the cooling system for the generator might fail, thereby resulting in the need to disconnect the generator in order to prevent damage to it even when the generator is lightly loaded.
[0008] U.S. Pat. No. 4,271,947 discloses an arrangement in which two axially aligned shafts engage each other via coaxial gears having teeth extending in the axial direction. A compression spring extends between the gears and urges an axially displaceable one of the gears to move away from the axially fixed gear. A fusible element having strengthening filaments therein acts to resist both the force of the compression spring and the axial forces resulting from torque transfer via the inclined surfaces of the gear teeth.
SUMMARY OF THE INVENTION
[0009] According to the present invention there is provided a drive disconnect device comprising:
[0010] an input element having a first axis and a first connection region carrying first engagement elements;
[0011] an output element having a second axis and a second connection region carrying second engagement elements;
[0012] restraint means; and
[0013] biasing means;
[0014] wherein the input element and output element can undergo relative axial displacement with respect to one another between a coupled position where the first engagement elements cooperate with the second engagement elements such that the input element is drivingly connected to the output element, and a decoupled position where the first and second engagement elements are disengaged from one another, the biaising means acts to urge the input and output elements towards the decoupled position and the restraint means serves to resist the urging of the biaising means until the temperature of the restraint means exceeds a predetermined value, and wherein the engagement elements extend only axially along at least one of the input and output elements.
[0015] It is thus possible to ensure that the contacting surfaces which serve to transmit load between the input element and the output element engage each other on a surface with which the first axis or the second axis is parallel.
[0016] It is thus possible to ensure that the force acting on the restraint means does not vary as a function of the torque being transmitted by the drive disconnect coupling.
[0017] Preferably the first and second engagement elements are splines. The first engagement elements may extend radially outward from the input element and the second engagement elements may extend radially inward from the output element. The input element is preferably radially smaller than the output element such that it can be partially disposed within the output element and movable axially with respect to the output element.
[0018] Preferably the input element carries a third engagement region for releasably engaging with a drive shaft of a prime mover, or with a coupling element connected to a drive shaft.
[0019] Preferably the coupling element acts to inhibit lubricant loss from around the drive shaft when the drive disconnect device is in its disconnected state.
[0020] Preferably the third engagement region cooperates with a fourth engagement region carried in the coupling element such that the input element is drivingly connected to the coupling element when the input element is coupled to the output element.
[0021] Advantageously the third and fourth engagement regions disengage from one another when the input element decouples from the output element. A further biaising device may be provided to urge the input element to drivingly disconnect from the coupling element.
[0022] Preferably the biasing means comprises at least one spring. The or each spring may be a wave spring, and where multiple wave springs are provided these may be stacked in a crest to crest fashion. This is the advantage of providing a spring configuration which when in its compressed state takes up a relatively small amount of space in the axial direction, but which can give a relatively high degree of expansion.
[0023] Advantageously the restraint means is formed from a material, such as a eutectic mixture or solder whose melting temperature is well controlled. The material is selected such that it will melt at a temperature that will be attained by the lubricant if the device driven by the coupling fails or overheats. Preferably a pellet or column of the eutectic material is formed and is positioned such that it either directly or indirectly bears the load provided by the biasing means. Advantageously the eutectic is placed within a substantially sealed container such that, as it melts, it is restrained from coming into contact with lubricants used in the vicinity of the drive disconnect device.
[0024] In a preferred embodiment, the eutectic mixture is provided in the form of a cylinder (i.e. a hollow column). The cylinder of eutectic material is advantageously in contact with a container. The container may, for example have the profile of a disk having two upstanding walls disposed at different radii from the center of the disk. The container may itself then be positioned such that the base and/or walls thereof are directly bathed in lubricant or in good thermal contact with components that themselves are bathed in lubricant, such as oil. This arrangement helps to ensure good heat transfer between the lubricant and the eutectic restraint means. This is advantageous to ensure rapid operation of the disconnect mechanism.
[0025] Thus the individual elements of profiling the connection between the input and output elements so as to remove axial force acting on the eutectic (thereby allowing less eutectic to be used to obtain the necessary physical strength) and the good thermal contact between the eutectic and the lubricant each give significant operational advantages and together provide a thermal disconnect mechanism having significantly reduced disconnect period, i.e. it disconnects much more quickly because the heat from the lubricant is transferred more quickly to the eutectic.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The present invention will further be described by way of example with reference to the accompanying drawings, in which:
[0027] [0027]FIG. 1 is a cross-section through a drive disconnect device constituting a first embodiment of the present invention; and
[0028] [0028]FIG. 2 is a cross-section through a drive disconnect device constituting a second embodiment of the present invention.
DETAILED DESCRIPTION
[0029] The thermal drive disconnect device shown in FIG. 1 and generally indicated 1 , comprises a circularly symmetric input shaft 2 carrying a first set of splines 4 at a first end 5 thereof, and a second set of splines 6 at a second end 7 thereof. The first end of the shaft is, in use, in driven engagement with a generally cup shaped coupling element 8 which has radially inward facing splines 10 to engage with the splines 4 and also radially outward facing splines 12 for engaging with a drive element (not shown) forming part of or driven from a prime mover. The coupling element 8 has a region 14 of increased diameter which carries a radial recess 16 for accepting an oil seal such that the coupling element may be attached in fluid sealed rotary engagement with a housing (not shown) constituting part of the prime mover or a device driven therefrom. The purpose of the coupling element is to ensure that a lubricant for the prime mover is not lost from the prime mover when the drive disconnect device moves to a disconnected state.
[0030] The second end 7 of the input shaft extends partially within a cylindrical output element 20 which has a portion 22 carrying radially inward facing splines 24 which normally engage with the splines 6 . The output element 20 carries and is drivingly connected to an output gear 26 which, in use, engages with other gears (not shown). The output gear 26 is an integrally formed part of a generally cup shaped carrier which engages with the output element 20 via splines and which has an end wall portion 28 which extends radially inwards and acts to form a support for a cylindrical chamber 30 which contains a fusible compression element 32 . The element 32 is made from a eutectic mixture, similar to a solder, such that its melting point can be accurately controlled. The container 30 has an open mouth 34 . An elongate cylindrical element 36 extends through the mouth 34 and has an end portion 38 which abuts the fusible element 32 . The cylindrical element 36 has a flange 40 formed at its end nearest the coupling element 8 , which flange abuts against a first face of a shoulder 42 formed in the input element 2 . The shoulder 42 defines two faces. A second face, which faces towards the coupling 8 acts as an abutment surface for a compression spring, or plurality of compression springs 44 which extend between the shoulder 42 and an end wall 46 which is part of or rotates with the output element 20 . The compression springs 44 act on the input element 42 to urge it away from the position shown in the accompanying figure, and to move along the direction of arrow A such that the splines 6 and the splines 24 disengage from one another thereby decoupling the drive from the shaft 2 to the output element 20 .
[0031] The gear 26 and its supporting structure is rotatably held with respect to a fixed supporting structure (not shown) by bearings 50 and 52 .
[0032] The first end of the input element 2 has a centrally positioned hole 54 through which a rod 56 extends. The rod 56 cooperates with the spring 58 whose ends are secured to the rod 56 and end wall of the element 2 , respectively, such that spring 58 is held under tension when it is at the configuration shown in FIG. 1. As shown in the accompanying figure, the rod 56 has an enlarged head which engages with the coupling element 8 via a conical face.
[0033] This arrangement means that the thermal disconnect device and coupling element 8 can be formed as an integral unit allowing service personnel to replace them as a single unit.
[0034] In use, the disconnect device is normally in the configuration shown in FIG. 1. Thus drive from a prime mover (not shown) is transmitted via the coupling element 8 and it's splines to the input element 2 and from the input element 2 to the output element 20 via the splines 6 and 24 . This causes the gear 26 to rotate which then transmits the drive to other elements downstream of the disconnect device. The disconnect device is normally housed in the same casing as the load device and shares its lubricating medium.
[0035] If the load enters a failure mode, it is well recognised that the friction resulting from the failure will rapidly warm the lubricant. Since the device 1 is in intimate contact with the lubricant (it will normally be sprayed with oil during use) then any increase in the lubricant temperature is rapidly transmitted to the disconnect device. Once the lubricant temperature exceeds the thermal cut-out value, the heat within the lubricant causes the fusible element 32 to melt. The molten eutectic mixture is thrown towards the side walls of the chamber 30 due to centrifugal force, since the output element 20 and casing 30 are undergoing rotary motion. The melting of the fusible element 32 means that it is no longer in a position to provide a force, transmitted via element 36 and flange 40 , to oppose the bias force exerted by the spring 44 . Thus, under the urging of spring 44 the input element moves along the direction indicated by arrow A. The amount of travel is selected such that the splines 6 and 24 become uncoupled thereby disengaging the input element from driving connection with the output element 20 . During this movement, the element 36 is also driven along the direction of arrow A, such that its end section 38 moves into the chamber 30 . Given that the torque transmitted through the disconnect coupling may be quite large, the spring 44 has to have sufficient strength in order to overcome the frictional engagement between the splines 6 and 24 . Once the splines have become decoupled, the torque acting between the coupling element 8 and the input shaft 2 becomes much reduced. However, it is advantageous that this drive connection should also be uncoupled. The relative length of the splines 6 and 4 could be selected such that spring 44 will always cause both driving connections to become uncoupled as it expands. However, it is advantageous to include the spring 54 in combination with the rod 56 which acts to ensure that the connection between splines 4 and 10 also becomes uncoupled. It should also be noted that the device must disconnect when the drive torques are low. This condition may arise when a generator has turned off. This would normally be expected to reduce the temperature within the housing. However, if, for example, the cooling system for the generator has failed then the temperature may continue to rise thereby triggering the disconnect even under low load conditions.
[0036] It is worthwhile noting that a technician can tell if the disconnect has operated by attempting to turn the coupling element 8 by hand. In general he will be able to turn it if the disconnect has operated, but not be able to turn it if the disconnect device has not operated.
[0037] It is thus possible to provide a thermal decoupling device wherein the use of axially aligned splines means that the force borne by the fusible element 32 becomes that derived solely from the springs 44 and is not increased as a result of the torque being transmitted through the coupling device. This means that the size of the fusible element 32 can be more accurately selected, since its crushing load is determined by the spring 44 , and thus a more rapid and reliable disconnect can be achieved compared with the prior art arrangements using helical splines or dog teeth where the transmission of torque necessarily induces a further crushing load. Furthermore, the compression spring no longer has to be strong enough to overcome the separating loads generated by the use of helical splines or dog teeth and consequently the forces acting within the disconnect element become reduced and the operation of the device becomes more predictable and reliable.
[0038] [0038]FIG. 2 schematically illustrates a second embodiment of a thermal disconnect. Parts of this embodiment which are similar to or identical with those described hereinbefore with reference to FIG. 1 are indicated by the same reference numbers. The device shown in FIG. 2 differs from that shown in FIG. 1 primarily by the way in which the eutectic element is held. In this arrangement the chamber 30 is replaced by a modified chamber 130 which is circularly symmetric and which comprises an end wall 132 , a first cylindrical wall 134 extending from the end wall 132 into the body of the disconnector device, and a second cylindrical wall 136 having a greater radius than the first wall 134 , also extending from the end wall 132 into the body of the thermal disconnect device. Thus the container 130 defines a circularly symmetric U-shaped channel 138 . A eutectic element 140 , in the form of a cylindrical wall and optionally having a disk shaped end portion 142 is disposed within the U-shaped channel 138 so as to be in intimate contact with the walls 132 and 134 .
[0039] An annular piston 150 is positioned such that a first portion 152 thereof bears against the end face of the eutectic cylinder 140 which faces into the disconnect element, whereas a second portion of the annular piston 150 defines an annular shoulder 154 which bears against a co-operating shoulder of the input element 2 via an intermediate elastomeric washer 156 so as to prevent fretting. Thus, the compressive load exerted by the springs 44 is transmitted to the input element via the shoulder 42 and from the input element it is transmitted to the eutectic 140 via the annular shoulder 154 , the co-operating shoulder on the input element 2 , the elastomeric element 156 and portion 152 of the piston 150 . This, in turn, causes the eutectic 140 to bear against the end wall 132 of the container 130 . The container 130 is constructed such that it can withstand the compressive forces without deformation.
[0040] A modified end cap 160 is provided which forms an annular end portion 162 against which part of the end wall 132 is able to bear against in use, thereby holding the container 130 in its correct position. The end cap 160 thereby also defines a circular orifice, generally indicated 164 which leads into a cylindrical chamber, generally indicated 166 defined by the walls 134 of the container 130 . Thus lubricant within the machine incorporating the thermal disconnect element can wash over the internal wall 134 , thereby rapidly transferring heat to the eutectic mixture 140 . Thus the eutectic restraining element 140 is in excellent thermal contact with the lubricant. Any warming of the lubricant due to a failure within the device is rapidly transferred to the eutectic element 140 , and if the lubricant temperature exceeds the eutectic melt temperature, the element 140 melts. This, as before, removes the force opposing expansion of the spring 44 , thereby allowing the input element 2 to move out of driving connection with the output element 120 . In the arrangement shown in FIG. 2, the output element 120 differs from the corresponding element shown in FIG. 1 in that the output gear 26 is formed as an integral part thereof.
[0041] A further modification to the arrangement shown in FIG. 2 relates to the connection of the pin 56 . As shown in FIG. 1, the spring 58 extends between a nut and an end wall of the element 2 . In the new embodiment the nut is replaced by a frame 180 which is rigidly secured to the rod 56 . The frame 180 defines a wall having an aperture therein. A locking pin 182 extends through the apertures to hold the frame in position with respect to the input element 2 .
[0042] It is thus possible to provide a further drive disconnect device whose operation is similar to that of the first drive disconnect device described herein, but which allows lubricant to be in intimate contact with the eutectic restraint means via a relatively thin intermediate wall 134 . | A drive disconnect device is provided in which input and output shafts are provided in splined engagement. The splines are aligned with the axes of the input and output shafts such that the force acting between the shafts in a separating direction is substantially invariant of the torque being transmitted. The shafts are spring biased to a disengaged position. The biasing force is resisted by a meltable restraining element which is arranged to melt when the temperature exceeds an acceptable value so as to allow the spring to cause the shafts to disengage from one another. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to improvements in radio control systems, and more particularly to a control system of the type which facilitates timely reliable communications intership or between the ship and the harbor/shore facilities, and which facilitates intraship communications, as well.
2. Description of the Prior Art
Shipboard telecommunications is in an increasing state of development especially in view of the widespread availability and usage of digital electronics. One of the problems encountered in shipboard communications is the extremely hostile environment in which high frequency communications are conducted. The metal ship hull and structures act as reflectors to the signals, exaccerbating an already difficult communication situation. Not uncommonly, for example, even today ships at sea have periods of from several hours to days during which communications, if possible at all, are by way of CW Morse code. Thus, there have been many proposals for equipment to enable more reliable communications. One proposal is for so called automatic error request (ARQ) operations, in which a teletype over radio signal is transmitted, and as it is received, confirming signals are returned. Thus, whether or not the message has been received is known to the transmitting station.
Another system which has been receiving recent attention is selective calling techniques, especially such techniques which can be digitally implemented. Typically, a digital selective calling (DSELCALL) operation is as follows. A message is constructed having certain portions formatted in accordance with predefined codes. The first portion of the sequence presents a format specifier, such as a distress call, an all ships call, or the like. The second portion is the address of a ship or class of ships to which the message is intended. The third portion indicates the priority of the message, such as urgent, routine, safety, etc. The fourth portion is the identification of the sending station, and the fifth portion includes the messages or messages to be transmitted. The total length of the message may be of predefined length, for instance, of up to 90 characters, and may typically contain information regarding the type of distress, if a distress message is involved, for example, or other information, as needed. In addition, the message may be directive; for instance, the message may request the receiving station to receive an extended message from the transmitting station on another frequency, for example, by teletype over radio. In such case, the message may set forth frequencies on which the teletype message will be sent. When such a message is received, the radio operator will configure a receiver and transmitter to operate on the specified frequencies. Usually, an ARQ unit is associated with such teletype operations, so that as the teletype message is being transmitted and received, confirmation signals are being transmitted to insure correct reception of the signal.
Because of the increasing telecommunication needs of commercial ships, increasing numbers of radio equipment and the like are being installed on ships. Usually, for example, there are one or more high frequency transmitters and receivers, as well as one or more very high frequency transmitters and receivers. There are many subuses for the equipment, such as providing telephone patch service for the people on board, providing telegraph service, providing teletype service and receiving weather and other information, and providing other communications pertaining to the ship's operation and business.
In addition to communication requirements to locations outside the ship, included in the radio specifications of most ships, are certain sensor functions. For example, most ships include sensors for indicating the ship's speed, heading and position, as well as the state of the sea, the winds, the weather, and so forth. Often, it is desired to communicate this information to other locations, such as nearby ships, or to land based "home" stations.
Of particular interest to shipboard personnel is the effective signalling of alarms. Some alarms typically used are distress, distress relay, vital safety, urgent messages, important safety, routine business, routine, VHF selective ringer and so forth. It can be seen that depending upon the alarm, it may be desired that selected ones of the alarms be sounded or displayed, or not sounded or displayed, in certain areas, such as officer's quarters, the wheelhouse, the radio officer's quarters, as necessary. In addition, some alarms may need to be broadcast or rebroadcast (if, for example, the alarm is a distress call received from another ship which requires the alarm to be rebroadcast), to nearby ships or land stations, as required.
Typically, shipboard radio and electronic apparatuses are operated and maintained by a radio officer. Usually, the radio officer is charged with the duty to operate the equipment during normal hours and with the duties to maintain and repair the equipment during overtime or non-working hours. This schedule may be particularly expensive to the ship owners, especially if significant overtime is needed.
It is therefore desirable to provide a system by which the ship's radio and electronic equipment can be operated in a non-attended manner, or in a manner requiring minimum attention of the ship's personnel. However, as set forth above, the system must also be capable of making decisions, for instance, to rebroadcast alarms, to direct alarms to preselected shipboard locations, to receive certain communications for later review or dissemination, and the like.
BRIEF DESCRIPTION OF THE INVENTION
In light of the above, it is, therefore, an object of the invention to provide a radio telecommunications system for maritime use.
It is another object of the invention to provide a radio telecommunications system of the type described the operation of which can be managed by a central processing unit or a programmed microcomputer or microprocessor.
It is another object of the invention to provide a radio telecommunications system of the type described which provides microprocessor control of HF radiotelephone; VHF FM radiotelephone; HF radiotelegraph, including CW, simplex TTY over radio, automatic error request, forward error control, and digital selective calling; and HF special meteorological data reception.
It is another object of the invention to provide a maritime radio telecommunications system of the type described which can additionally manage the ship's alarm functions.
It is another object of the invention to provide a maritime radio telecommunications system which can be operated in an unattended manner, or in a manner which requires minimum operator attention.
It is another object of the invention to provide a radio telecommunications system with which remote communications can be had during unattended operation.
It is another object of the invention to provide a radio telecommunications system which can be addressed and operated from a remote location.
These and other objects, features and advantages will become apparent to those skilled in the art from the following detailed description when read in conjunction with the accompanying drawings and appended claims.
In accordance with a broad aspect of the invention, a radio system for automated ship board operation includes a plurality of radio receivers and a plurality of radio transmitters. An ARQ unit is provided with which one of the receivers and one of the transmitters is associated. A DSELCALL unit is provided with which another one of the receivers and another one of the transmitters is associated. A VDT unit is provide upon which radio information and messages can be displayed upon reception and composed for transmission. Means also are provided which are automatically responsive to control instructions entered into the VDT for configuring the plurality of transmitters and receivers, and includes selectively associating the receivers and transmitters with the DSELCALL unit and the ARQ unit in accordance with the control instructions, scanning the receiver associated with the DSELCALL unit among preselected DSELCALL frequencies, and controlling the transmitter associated with the DSELCALL unit in accordance with the frequency of the scanned receiver, and controlling the operation of the receivers and transmitters associated with ARQ unit as needed.
BRIEF DESCRIPTION OF THE DRAWING
The invention is illustrated in the accompanying drawing in which:
FIG. 1 is a perspective view of a ship on which a radio telecommunications system in accordance with the invention is installed, illustrating, in particular, a preferred placement of various antennas used in conjunction with the radio telecommunications system.
FIG. 2 is a front view of a preferred configuration of a radio telecommunications system, in accordance with the invention.
FIG. 3 is a box diagram of the radio telecommunications system of FIGS. 1 and 2, in accordance with the invention.
FIGS. 4a and 4b are box diagrams of the HF transmitter and receiver portions of the system of FIGS. 1, 2 and 3 in accordance with the invention, in greater detail.
FIGS. 5a and 5b are box diagrams of the audio and control systems of the system of FIGS. 1, 2, and 3, in accordance with the invention, in greater detail.
And FIGS. 6a and 6b are flow charts of a preferred computer program for operation of the central processing unit of the radio telecommunications system in accordance with the invention for automatically operating the system.
In the various figures of the drawing, like reference numerals are used to denote like parts. In addition, various sizes and dimensions of the parts have been exaggerated or distorted for ease of description and clarity of illustration.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The radio telecommunications system of the invention is intended for maritime use, and can be installed on an ocean going vessel, such as the ship 10, shown in FIG. 1. Externally mounted on the ship 10 are the various antennas, at various locations as is next described in detail.
Two VHF antennas 12 and 13 are located near the top of the mast of the bridge 11. Two HF transmit antennas 15 and 16 are mounted on the port and starboard sides of the bridge 11, and two VHF receive antennas 18 and 20 are located amidship on the deck on each side of the stack 21. Additionally, on each wing of the bridge 11, handset/speakers 22 and 23 are respectively located. An MF antenna 24 is mounted on the port side of the bridge, and a reserve MF antenna, 25 extends around the after section of the bridge.
Other parts of the radio telecommunications system in accordance with the invention are mounted at various selected locations of the ship. For example, the bridge-to-bridge VHF radio and VHF monitors (not shown) can be placed at the conning console wheelhouse 28. Extension indicators (not shown) can be located at the watch standers console wheelhouse 30, as well as in the radio officer's quarters 31. The main VHF radio control (not shown) also can be located at the conning console wheelhouse 28. Finally, the teletypewriter (not shown) can be located in the purser's office 33.
It should be noted that the placement of the various antennas and equipment is intended to be exemplary of a typical installation, and that other configurations may also be equally advantageously employed, as will be apparent to those skilled in the art.
A preferred arrangement for the radio telecommunications system components within the ship is shown in FIG. 2, and is denoted by the general reference numeral 40. The radio telecommunications system is mounted in four adjacent equipment racks 41, 42, 45, and 46, which can be installed, for example, in a ship's radio room, or other convenient location, not shown. The system 40 includes the following equipment in the first rack 41: a VDU (video display unit) 48, for human interface, including a video display screen 49 and operator keyboard 50. Mounted in the rack 41 above the VDU 48 is a control panel 56 for two VHF FM transceivers (not shown) carried directly behind the control panel 56. The VHF transceivers are used for communications to the bridge, for bridge to bridge communications, ship's primary communications, phone patch, distress and vessel traffic channel monitoring and scan lock frequency monitoring for the selective ringing alert tones. Carried upon the panel 56 is a telephone handset 58 for use in the above described communications. Mounted above the VHF radio control panel 56 is a central processor 60, which, in essence, controls the various equipments comprising the radio telecommunications system in accordance with the invention as will become apparent from the discussion below. Finally, above the central processor 60 is a VHF scan control and the main VHF power transceiver panel 62.
The second rack 42 includes the operator control panel 65, from which, in conjunction with the VDU keyboard, the entire radio telecommunications system 40 can be operated, for example, in the specification of frequencies of the transmitters and receivers, the selection of locations on board the ship at which various inputs and outputs are directed, and, in general, in any aspect of the radio telecommunications system which can be controlled by the operator.
Above the operator control panel 65 in the second rack 42 is a high frequency receiver 66, which can conveniently be a HF receiver sold by Rockwell International Corporation identified as a Collins 851S-1 HF Receiver. As will become apparent from the following description, the HF receiver 66 is one of three such units, the other two 68 and 70 being emplaced in similar locations in racks 45 and 46, respectively.
Above the HF receiver 66 in the second rack 42 is an audio matrix 71, which serves to route the transmitting and receiving audio signals among the various equipments of the radio telecommunications system in accordance with the invention, and the operation of which is described in detail below with reference to FIG. 5. Above the audio matrix 71 is a receive antenna matrix 72, described in detail below with respect to FIG. 4.
A distress frequency watch receiver 75 is located above the receive antenna matrix 72 in the second rack 42, and, finally, the main power panel 76 is installed in the uppermost location.
In the third rack 45, immediately below the HF receiver 68, is the phone patch 79 and transceiver relay 80. Above the HF receiver 68 is a high frequency exciter 83 for one of the two HF transmitters. To complete the front panel of the rack 45 is a receiver multicoupler and filter 84.
In the fourth rack 46, as mentioned above, is the third HF receiver 70. Above the HF receiver 70 is a second high frequency exciter 87. The high frequency exciters 83 and 87 are connected to respective power amplifiers to transmit onto respective antennas 15 and 16 on the ship's bridge (see FIG. 1).
Above the HF exciter 87 in the fourth rack 46 is an ARQ terminal 90, and immediately above the ARQ terminal 90 is the digital selcall unit 91. Immediately above the digital scall unit 91 is an HF scan tone detector 93, which operates in conjunction with the HF receivers 66, 68, and 70, under the control of the central processor 60.
The system described above with reference to FIGS. 1 and 2 is shown in block diagram form in FIG. 3. As illustrated, the system includes five main sections, each encircled by dashed lines: the control subsystem 100, the voice and data subsystem 101, miscellaneous equipment 102, radio transmitter and receiver subsystems 104, and various antenna arrays 105. (Power subsystems are additionally included, but are not shown for clarity.)
Each of the subsystems is configured as presently described. The control subsystem 100 includes the central processor keyboard and display 110. The voice and data subsystems include teletypes 112, including an ASR and an REPERF teletype system, both controlled via line 113 from the central processor keyboard and display 110. An ARQ/SITOR unit 114, a high frequency digital selective callin9 (DSELCALL) unit 115, an operator control panel 116, and a phone patch unit 117, are also provided with output lines 122-125 respectively connected to a combined transmit and receive audio matrix 130. The ARQ/SITOR unit 114 is connected by a line 132 to the central processor keyboard and display 110, and, in similar fashion, the HF digital selcall unit is connected by a line 133 to the central processor keyboard and display 110. The HF digital selcall unit 115 additionally includes two extension indicators 134, described further below. The miscellaneous equipment subsystem 102 includes a weather facsimile unit 138 and a time tic box 139, connected by respective lines 140 and 141 to the combined transmit and receive audio matrix 130. Additionally, ship distribution lines 142 are provided within the miscellaneous equipment subsystem 102 to the combined transmit and receive audio matrix 130.
The transmitter and receiver subsystem unit 104 includes a high frequency subsystem 150 which includes two high frequency transmitters and three high frequency receivers. A 2182 kilohertz watch receiver and remote unit 152 is provided, as well as a VHF subsystem 154 including a main VHF radio, a bridge-to-bridge radio, two monitor receivers, and a VHF scanning receiver. A medium frequency (MF) subsystem 156 is also provided within the receiver and transmitter subsystem 104.
Finally, in the antenna array 105, two transmitter antenna couplers 160 are connected to the transmitters of the high frequency subsystem 150 by line 161, each couples the output of a respective HF transmitter to a selected transmitter antenna, (both antennas being indicated by the single antenna symbol 164). The two antennas 164 correspond to the high frequency transmit antennas on the bridge, indicated by reference numerals 15 and 16 in FIG. 1. The receivers of the high frequency subsystem 150 are connected by line 168 through an antenna matrix 169 to a multicoupler 170, each to a respective one of the two receiver antennas indicated by the symbol 172. The two antennas indicated by the symbol 172 are identified as the high frequency receiver antennas 18 and 20 in the midship portion of the ship 10 shown in FIG. 1. Additionally connected to the multicoupler 170 via line 174 is the 2182 kilohertz watch receiver and remote unit 152.
The radios of the VHF subsystem in unit 154 are connected directly to respective selected VHF antennas indicated by the symbol 180. The VHF antennas 180 are shown by antennas 12, 13 and 14 on the mast of the ship 10 in FIG. 1.
Finally, the medium frequency subsystem is connected directly to a main antenna 182 and a reserve antenna 183, corresponding to medium frequency antennas 24 and 25, respectively, on the ship 10 in FIG. 1.
The high frequency transmitters and receivers are shown in greater detail in FIGS. 4a and 4b. The two high frequency transmitters indicated within the box 150 in FIG. 3 are designated by respective reference numerals 200 and 201. Each contains the same equipment and, for brevity, the respective parts of each are indicated by the same reference numeral with corresponding parts being indicated by a reference numeral and the numeral followed by a prime ('). The transmitter 200 includes an exciter 201, a one kilowatt amplifier 202, a harmonic filter 205, and a transfer relay 206. The unit is powered by a one kilowatt power supply 209. The operation of high frequency transmitters being well known in the art, is not described in detail herein. The output from the transmitter 200 is connected to coupler house 210 within which an antenna coupler 212 connects the output from the transmitter section 200 to the antenna 15. In like fashion, the output of transmitter 201 is coupled to the transmitter antenna 16. Additionally, within the coupler houses 210 and 211 are coupler junction boxes 215 and 215' which interconnect the harmonic filters 205 and 205' with the antenna couplers 212 and 212'.
The exciter of the transmitter receives the audio to be transmitted from input lines 216 and 217. In addition, the exciters 201 and 201' are connected to a key line interlock relay (not shown) by lines 220 and 221, respectively. The exciters 201 and 201' are controlled by the central processing unit 110 (see FIG. 3) on control line 223, all as below described.
The receiver sections of the high frequency system include three high frequency receivers 225, 226, and 227, each of which is also controlled by the central processor 110 (see FIG. 3) by control signals on the line 223. The receivers 225-227 produce audio outputs on respective audio lines 230, 231, and 232 connected to an antenna matrix 235, which, incidentally, produces outputs to an MX auxiliary antenna on line 237 and to a ships antenna system amplifier (not shown) on line 238. The input to the antenna matrix is derived from a multicoupler section 240 which is connected via lightning arrestors 241 and 242 to respective high frequency receiver antennas 18 and 20. Additionally connected to one of the multicouplers of the multicoupler unit 240 is the 2182 kilohertz watch receiver 152 and a 2182 kilohertz receiver remote unit 250 which may be located, for example, at a remote location such as the ship's wheel house.
The voice, data and control systems are shown in block diagram form in FIGS. 5a and 5b, by which the telecommunications system of the invention can be controlled. The overall system is controlled by a central processor unit 256 which can be, for example, any properly programmed digital computer, such as the digital computer sold by Data General Corporation under their trademark "Micronova". A video display terminal 257 and data entry keyboard 258 are provided for operator interface with the central processor unit 256. The various transmitter and receivers of the telecommunications system of the invention are controlled by the central processor 256, via control line 260 which are provided for this purpose. Thus, the various frequencies of the various selected receivers or transmitter can be selected in accordance with predefined selection criteria entered into the central processor unit 256, to be controlled as needed. Additionally connected to the central processing unit 256 is one or more teletypewriter units 262 and 263 (connections not shown) which may be located at various locations, such as the radio room or the purser's office, or other locations, as desired. The central processing unit 256 also controls various extension indicators of the telecommunication system, such as the extension indicators 264 and 265, indicated to be in the wheel house and radio officer's stateroom, respectively. In addition to the foregoing, the central processor unit 256 controls the digital selective calling (DSELCALL) system, indicated generally by the reference numeral 267, and which contains a DSELCALL unit 268, an ARQ terminal 269, and a scan tone detector 270, via control lines 272, 273, and 274, respectively.
The DSELCALL unit 268 is connected to the central processing unit 256, and to the extension indicators 265 and 266, for example, in the wheel house and radio officer's stateroom, respectively, as shown. The ARQ terminal is connected by lines 280 and 281 respectively to the received audio matrix 285 and to the transmit audio matrix 286. In like fashion, the DSELCALL unit 268 is connected by lines 287 and 288 respectively to the received audio matrix 285 and transmit audio matrix 286. The line 287 between the DSELCALL unit 268 and the receive audio matrix 285 is connected by line 289 to an input of the scan tone detector 270. Thus, the scan tone detector 270 can scan the received audio tones received on the audio matrix 285 concurrently with the reception of data received by the DSELCALL unit 268 from the selected HF receive radio via the audio matrix 285. The receive audio matrix 285 receives audio from all of the various radio audio sources, including the HF received audio on lines 291, 292, and 293, audio from the main VHF receiver on line 296, and the audio from the medium frequency receiver on line 297. The transmit audio matrix 286, in a similar fashion, delivers audio to the HF transmitter on lines 300 and 301, and to the main VHF radio on line 303.
Additional connections can be made to the receive audio matrix 285, for example, by the inclusion of a weather facsimile device 310, a time tick box 311 (for example via an operator panel 312). In addition, the ships entertainment system can receive audio from the medium frequency receiver on line 315, and, if desired, a spare output line 316 can be provided.
The overall control for the system can be established in an operator control panel 330 which may include various interlock relays 331, CW side tone generators 332, distress tone generators 333, a microphone 334 and speaker 335. Finally, a phone patch 340 may be included, if desired, and connected to the receiver audio matrix 285 and transmit audio matrix 285 and transmit audio matrix 286 by lines 341 and 342, respectively.
As mentioned, the entire telecommunications system 40 (see FIG. 2) is configurable by the central processor unit 256 (see FIG. 5a). Thus, the operator, by entering the appropriate commands in the keyboard 258 can instruct the central processor unit 256 to configure the system in any manner in which the particular operator chooses. An example, of such selection can be to associate one of the HF radio transmitters, such as the transmitter 200 (see FIG. 4) with the ARQ terminal 269, and the other transmitter 201 with the DSELCALL unit 268. The operator may also optionally associate one of the receivers, such as the receiver 255, with the ARQ terminal 269 and another receiver, for example receiver 226, with the DSELCALL unit 268 and the scan tone detector 270. Other assignments, may of course be made within the discretion of the radio operator. With the assignments made as above described, under the control of the central processor 256, the DSELCALL and scan tone detector can be automatically operated in accordance with a predetermined computer program under which the central processor unit operates.
A preferred embodiment of such computer program is shown in flow chart form in FIGS. 6a and 6b. The DSELCALL unit and system are first initialized, as indicated by boxes 350, 351, and 352 in which the DSELCALL unit is associated with an appropriate high frequency receiver and transmitter, and in which the various preset values to be detected are placed within the DSELCALL unit. The scanning routine is then begun at 354 and operates to cause the DSELCALL unit to scan all of the preselected DSELCALL frequencies, as will become apparent. The scanning routine causes the first frequency to be scanned to be loaded into the DSELCALL unit 268, box 356. The associated HF receiver is then tuned to the selected receive frequency, box 358. If the scan tone detector 270 (see FIG. 5b) does not detect the appropriate DSELCALL tones, the loop is repeated beginning at point "A", at which time the next preselected DSELCALL frequency is loaded. The receiver is then retuned to the new frequency, and the presence or absence of DSELCALL tones is again determined, diamond 360. If the tone detector 270 detects the appropriate DSELCALL tones, with reference to FIG. 5b, a bit transition, or other signal, is sent on line 274 to the central processor unit 256 to lock the central processing unit 276 into DSELCALL unit 268 from further scanning, parallelogram 362. The tone detector lock is also sent to the DSELCALL, and on the high to low transition of the tone detector lock the DSELCALL relay closes. The closure of the scan relay is then inputted to the central processor unit. If the scan relay thereafter opens, the central processing unit resumes scanning, as will be described below. The scan process is repeated through all of the preselected DSELCALL frequencies and repeated continuously, unless a signal to be received is detected as mentioned, in which case, the signal is processed, as described below, and after which the scan routine is reinitiated.
When a signal is detected by the presence of tones, as described, and after the DSELCALL and scanner is locked onto the frequency on which tones were detected, a check is made for "dots", diamond 364. The "dots" test begins 3.2 seconds after the tone detector lock is sent. If "dots" are not received within 3.2 seconds, the scanning relay is opened and the central processing unit resumes the scanning process, beginning at point A on the flow diagram. It should be noted that 3.2 seconds is selected as a period during which the occurrance of a properly received DSELCALL signal must occur. Thus, if the "dots" are not received within that time, it is assumed that the signal received is not a proper DSELCALL signal, and, therefore, may be ignored. If "dots" are detected, the address portion of the received DSELCALL signal is decoded, box 366, and, a determination is made whether the received signal is addressed to the receiving ship, diamond 368. If not, the scanning process is resumed from point "A" in the routine. If the decoded address indicates the signal is for the particular ship with which the ship is associated, the message is then received and decoded, box 369. The decoded message is compared against messages previously received and stored in memory, box 371, and if not identical to a message already in memory, decision diamond 370, it is stored in memory for recall or retransmission, as desired, box 371. The stored message is addressed on line "C" by a recall requirement decision, diamond 377 and box 378. The decoded message received is then sent on lines 273 from the DSELCALL unit 268 to the central processing unit 256, parallelogram 372, and the CPU outputs the message received to an appropriate display, parallelogram 374 and box 376. It should be noted that the display can be any display selected, such as the teletypewriter if a hard copy is required, or, alternatively, on the video display unit, or both. Additionally, at this point, if desired remote indicators 265 at various locations within the ship can be turned on to indicate to monitoring personnel the reception of a DSELCALL message.
At this juncture, a determination is made whether the incoming message includes a request to send additional radio traffic to the receiving ship, diamond 379. If so, the routine for acknowledging the received signal is skipped, jumping to input point "B" in the routine for receiving the traffic, to be described below. If there is no additional traffic requirement, the DSELCALL signal is acknowledged. A check is first made of the system configuration, box 380, during which a check is made whether transmitter #1 or transmitter #2 is associated with the DSELCALL unit. If neither transmitter has been assigned to the DSELCALL function, the routine is ended, and the scanning process is returned to point "A" in the routine, diamond 382. If one of the transmitters has been assigned to the DSELCALL unit, the transmit address is loaded in the central processing unit, parallelogram 384, and control signals sent to the transmitter, box 386. The transmit frequency is then loaded by the CPU into the transmitter, parallelogram 388, and the transmitter tuned to the assigned frequency, box 390. When the tuning is complete, a signal is transmitted to the central processing unit, parallelogram 392. The DSELCALL unit then composes the acknowledgment message to be sent, box 394, and the message is then sent under the control of the central processing unit to the transmitter, parallelogram 396. The message is then transmitted, parallelogram 398 and box 400, and, upon the completion of the message transmission, the routine is continued, parallelogram 402.
It should be noted that in the repeat request determination and system configuration steps, diamond 379 and box 380, if the incoming message has a repeat request which is not a distress call (a distress call is automatically repeated, even though a repeat request is not received as a part of the message), the DSELCALL unit sends an ASCII "del" character to the CPU. The CPU tunes the assigned transmitter to the paired oscillator frequency and the DSELCALL keeps the scan relay closed during the transmission process. At this point, no additional incoming messages can be received until the CPU responds.
Looking again at the scanning and DSELCALL process within the CPU 256, beginning at point "B" in the routine, the CPU checks at this point for telecommands "T13", "T15", and "T16", diamond 404. If one of these telecommands is found, an ASCII "DC1" character is sent to the CPU before the receive frequency and a "DC2" character is sent before transmit frequency. The CPU will then tune the transmitter if one is assigned. The telecommands "T13, T15, and T16" indicate respectively the telecommunications mode and frequency, as is known in the art. T13, for example, indicates a receive mode on frequency F1, in teletypewrite mode and FEC operation. T15 indicates transceive mode on frequency F1 in teletypewrite mode for ARQ operations. T16 indicates a receive mode on F1, in teletypewrite mode. Thus, the "T13", "T15", and "T16" indicate the ARQ channel which should be used for the automatic error repeat function presently to be described.
Once the frequency or channel has been determined, if the number or channel detected is found not to be one of those used for the ARQ function, the process is terminated and the scanning routine resumed beginning at point "A" in the scanning routine. On the other hand, if one of the transmit frequencies is found, a determination is then made whether the ARQ unit or terminal 269 is busy, diamond 406. If it is busy, again the scanning process is resumed at point "A" in the program. If the ARQ unit is not busy, the appropriate indicated ARQ frequency is loaded in the CPU, parallelogram 408, the ARQ receivers are tuned to the assigned frequency, box 410, and the completion of the tuning process is indicated to the CPU, box 412. The CPU then checks only for the assignment of channel T15, diamond 414, and if not found, jumps to a lower point in the routine to be described. If channel T15 is found, the transmit frequency is loaded in the CPU, box 416 and the transmitter associated with the ARQ unit is tuned to that frequency, box 418. When the tuning is complete, the transmitter indicates the completion to the CPU, parallelogram 420. The ARQ mode is then set to a standby mode, box 422. The standby mode allows the ARQ and the selective FEC messages to be received. At this point, a parallel mode of operation of the system begins in which the system is permitted to resume the scanning at point "A" in the overall process. Concurrently, the ARQ message is processed by being sent and received, boxes 424 and 426, in the usual ARQ fashion. Upon the completion of the ARQ process, an end of work signal is sent to the CPU, parallelogram 428.
It can thus be seen that with the system including the central processing unit programmed in accordance with the flow chart above described, that automatic DSELCALL and ARQ operation can be achieved without a requirement for human intervention other than presetting or initializing the system with the assigned radio and transmitter pairs to the appropriate ARQ and DSELCALL units and inputting the desired operational frequencies into the DSELCALL scanner. It can also be seen that one of the primary advantages of the system as described is that during periods of adverse telecommunications environments that the data reception or message reception is automatically handled. That is, if a incoming message is detected but due to interference of various natures is unable to be totally properly received, the message will automatically not be acknowledged to provide to the transmitting station an indication requiring retransmission of the message at a later time.
It should be appreciated that although the process has been described as being applicable to messages received by the ship from such as a shore or remote location, it is equally applicable to messages originating on the ship itself. Such messages, for instances can be automatically generated messages at for transmission at predetermined times. For example, in some cases it may be desirable to transmit, say every six hours, a message from the ship to another location containing a report of the remaining fuel on board, or updated position reports, or the like. In such cases, the message is automatically generated, then placed in a queue in memory, effected by box 371 with an indication that a message is awaiting transmission, diamond 370. The message is then transmitted in its turn, in the same fashion as described above with respect to the retransmission of a message received from a shore or remote location.
Although the invention has been described and illustrated with a certain degree of particularity, it is understood that the present disclosure has been made by way of example only and that numerous changes in the combination or arrangement of parts may be resorted to by those skilled in the art without departing from the spirit and scope of the invention as hereinafter claimed. | A radio system for automated ship board operation includes a plurality of radio receivers and a plurality of radio transmitters. The system includes an ARQ unit, with which one of the receivers and one of the transmitters is associated. A DSELCALL unit is provided, with which another one of the receivers and another one of the transmitters is associated. A VDT unit is provide upon which radio information and messages can be displayed upon reception and composed for transmission. The system includes a computer control which is automatically responsive to control instructions entered into the VDT for selectively associating the receivers and transmitters with the DSELCALL unit and the ARQ unit in accordance with the control instructions, scanning the receiver associated with the DSELCALL unit among preselected DSELCALL frequencies, controlling the transmitter associated with the DSELCALL unit in accordance with the frequency of the scanned receiver, and controlling the operation of the receivers and transmitters associated with the ARQ unit as needed. | 7 |
BACKGROUND
So called “plug and perf” operations are well known in the downhole drilling and completions industry, particularly with respect to unconventional resource plays (unconventional gas, shale gas, tight gas and oil, coal bed methane, etc.). In a plug and perf operation, a bottom hole assembly is run, e.g., on wireline, into a borehole that is typically cased and cemented and could include both horizontal and vertical sections. The bottom hole assembly includes an isolation tool, a setting tool, and one or more perforation guns. The setting tool is actuated for packing off a production zone with the isolation tool. The one or more perforation guns are then positioned in the borehole and triggered by a signal sent down the wireline. Typically, ball type plugs are used for the isolation tools, e.g., as they provide fluid communication with lower zones, which enables sufficient fluid flow for redeploying the perforation guns in the event that they do not fire properly. After perforation, the bottom hole assembly (sans isolation tool) is pulled out and a ball or other plug member dropped from surface for engaging a seat of the isolation tool for impeding fluid flow therethrough. While the process works adequately, it requires a significant amount of time and fluid to pump a ball downhole. Bridge plugs are occasionally used instead of ball type frac plugs, but these bridge plugs do not enable the aforementioned redeployment of failed perforation guns. Accordingly, alternatives for reducing the time and resources required in plug and play operations while maintaining the benefits of ball type frac plugs are well received by the industry.
SUMMARY
A plug drop tool including a body defining a chamber, a plug initially housed in the chamber, and a member disposed with the body and actuatable for selectively enabling communication between the chamber and an annulus at least partially defined by the body, the plug movable into the annulus when the communication is enabled.
A bottom hole assembly including an isolation tool, a setting tool operatively arranged for setting the isolation tool in a downhole structure, the setting tool initially connected to the isolation tool and disconnectable therefrom after setting, and a plug drop tool coupled with the setting tool, the plug drop tool configured to drop a plug, the plug operatively arranged to travel downhole and engage the isolation tool after disconnection from the setting tool for enabling isolation by the isolation tool.
A method of performing a downhole operation including running a bottom hole assembly into a downhole structure, the bottom hole assembly including a setting tool, an isolation tool, and a plug drop tool, setting the isolation tool in the downhole structure with the setting tool, disconnecting the setting tool from the isolation tool, deploying a plug from the plug drop tool, and engaging the plug with the isolation tool for enabling isolation by the isolation tool.
BRIEF DESCRIPTION OF THE DRAWINGS
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
FIG. 1 schematically illustrates a downhole assembly;
FIG. 2 is a cross-sectional view of a plug drop tool of the assembly of FIG. 1 in a closed configuration;
FIG. 3 is a side view of the plug drop tool of FIG. 2 ;
FIG. 4 is schematically illustrates the downhole assembly of FIG. 1 in an actuated configuration;
FIG. 5 is a cross-sectional view of the plug drop tool in communication with an annulus; and
FIG. 6 is a side view of the plug drop tool of FIG. 5 .
DETAILED DESCRIPTION
A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
Referring now to FIG. 1 an embodiment of the current invention is illustrated, namely an assembly 10 run into a downhole structure 12 . The downhole structure, could be, e.g., a borehole that is lined, cased, cemented, etc. The assembly 10 is, e.g., run downhole by use of a wireline system. In the illustrated embodiment the assembly 10 includes an isolation tool 14 , a setting tool 16 , a perforation gun 18 , and a plug drop tool 20 .
For example, in one embodiment, the assembly 10 is, e.g., a bottom hole assembly for a “plug and perf” operation. In this embodiment, the assembly 10 is positioned downhole and the isolation tool 14 is set in the structure 12 by the setting tool 16 for packing off a production zone 22 . The isolation tool 14 and the setting tool 16 could be any suitable tools known in the art. For example, the isolation tool 14 could be retrievable, drillable, etc., and formed from composites, metals, polymers, etc. In one embodiment the setting tool 16 is an E-4 setting tool commercially available from Baker Hughes, Inc. The setting tool 16 is then uncoupled from the isolation tool 14 and the perforation gun 18 positioned within the structure 12 for perforating the zone 22 , as generally illustrated in FIG. 4 . Multiple perforation guns could be included in the assembly 10 for forming multiple perforated sections in each production zone.
After perforation, the uncoupled tools of the assembly 10 are removed (the isolation tool 14 remaining downhole) and a plug 24 , corresponding to a complementarily formed seat in the isolation tool 14 , is dropped downhole for isolating opposite sides of the plug tool 14 , e.g., thereby enabling a pressure up event to fracture the production zone 22 through the perforations formed by the gun(s) 18 . The plug 24 could be a ball or take any other suitable form or shape receivable by the isolation tool 14 . The isolation tool 14 could include any suitable seat, such as the one taught in U.S. Pat. No. 7,600,572 to Slup et al., which patent is hereby incorporated by reference in its entirety.
Advantageously, the assembly 10 includes the plug drop tool 20 so that the plug 24 can be dropped before or while the assembly 10 is pulled out so that the plug 24 only has to drop a small number of feet as opposed to plugs in conventional systems that must drop hundreds or thousands of feet from surface. In accordance with the above, the plug drop tool 20 is initially in the condition of FIGS. 2 and 3 during run-in and perforation and transitions to the condition of FIGS. 5 and 6 for deployment of the plug 24 after perforation.
In the initial configuration of the tool 20 as illustrated in FIGS. 2 and 3 , a valve member 26 is disposed with a window 28 formed in a body 30 of the plug drop tool 20 . The window 28 is in communication with an annulus 32 formed between the assembly 10 and the structure 12 , but, as shown in FIG. 2 , blocked from communication with a chamber 34 formed in the body 30 . Blockage of the window 28 accordingly blocks communication between the chamber 34 and the annulus 32 . By blocking communication between the chamber 34 and the annulus 32 , the plug 24 disposed within the chamber 34 can be run-in and moved with the tool 20 . A cap 36 is included with the tool 20 for preventing the plug 24 from exiting the chamber 34 during run-in and positioning of the perforation guns 18 . The cap 36 and valve member 26 may both be formed as sleeves or rods having passages therethrough for enabling the flow of fluid through the tool 20 .
The cap 36 is secured to the valve member 26 via at least one strut 38 for enabling forces exerted on the cap 36 to be transferred to the valve member 26 . For example the tool 20 could include a lead screw, spring or other resilient element, magnetic or hydraulically actuated components, etc., or any other device, mechanism, or system arranged for actuating the valve member 26 . This actuation system could be triggered, e.g., by a signal sent via the wireline on which the assembly 10 is run. At least one release member 40 , e.g., a set screw, can be included for preventing premature actuation of the valve member 26 , e.g., until a predetermined threshold force is applied to the cap 36 .
It is to be further appreciated that in addition or alternatively to axial movement, the member 26 could be actuated differently, e.g., rotational movement could align the struts 38 with the windows 28 for selectively enabling and disabling communication between the chamber 34 and the annulus 32 . In another embodiment, the windows 28 are opened by forming the valve member 26 from a material that is dissolvable, degradable, consumable, corrodible, disintegrable, or otherwise removable in response to a downhole fluid, e.g., acid, brine, etc. Regardless of the mechanism used, actuation (movement, disintegration, etc.) of the valve member 26 will open the window 28 , thereby enabling communication between the chamber 34 and the annulus 32 .
When the chamber 34 is in communication with the annulus 32 the plug 24 is able to exit the chamber 34 by passing through the window 28 into the annulus 32 . The plug 24 is operatively sized with respect to the annulus 32 , i.e., having a dimension smaller than that of a radial clearance through the annulus 32 . The radial clearance is generally defined by the radially largest portion of the tools past which the plug 24 must travel in order to engage with the isolation tool 14 (e.g., the drop tool 20 , perforation guns 18 , setting tool 16 , etc.). By being so sized, the plug 24 is able to pass by the drop tool 20 , the perforating gun 18 and setting tool 16 of the assembly 10 in order to engage in a corresponding seat of the isolation tool 14 and cause isolation as noted above.
While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular 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 claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. | A plug drop tool, including a body defining a chamber, a plug initially housed in the chamber and a member disposed with the body. The member is actuatable for selectively enabling communication between the chamber and an annulus at least partially defined by the body. The plug is movable into the annulus when the communication is enabled. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to texture compression techniques.
[0003] 2. Background of Invention
[0004] Compression and decompression intended to minimize the memory size needed to store 2D textures is a promising field of application for these techniques in the 3D graphic domain. This possible field of use is becoming more and more significant as the dimensions and number of these textures tend to increase in real applications. The level of detail tends to increase as required by some applications, such as 3D games, and, without the help of such techniques, memory size and bandwidth for access would tend to require increasing performance levels hardly sustainable in mobile, ultra low power, handheld systems. More to the point, these techniques are becoming increasingly important in wireless phone architectures with 3D games processing capabilities.
[0005] For example, assuming a texture dimension of 512×512 pixels 16 bit/color each and a depth of 3, the amount of memory needed is 1.5 M bytes. Assuming 20-30 frames per second, the memory bandwidth is 30 to 45 Mbytes/s.
[0006] Additional background information on this topic can be gathered from “Real-Time Rendering” by Tomas Akenine-Möller and Eric Haines, A. K. Peters Ltd, 2 nd edition, ISBN 1568811829.
[0007] A well-known solution in this scenario was developed by the company S3; the related algorithm is designated S3TC (where TC stands for Texture Compression).
[0008] This has become a widely used de-facto standard and is included in the Microsoft DirectX libraries with adhoc API support.
[0009] Compression is performed off-line at compile time and the textures are stored in the main memory. Decompression processes act to compress textures accessing the memory run-time. This means that only decompression is implemented in hardware form while compression is not.
[0010] Important parameters for the decompression engine are: steps needed to decompress textures and possible parallel operation; low latency between data-access-from-memory and data-out-from the decompression engine.
[0011] In order to better understand operation of the S3TC algorithm one may refer to an image in RGB format, where each color component R (Red) or G (Green) or B (Blue) is a sub-image composed by N pixels in the horizontal dimension and M pixels in vertical dimension. If each color component is coded with P bits, the number of bits per image is N*M*3*P.
[0012] For example, assuming N=M=256 and P=8, then the resulting size is 1,572,864 bits. If each sub-image R or G or B is decomposed in not-overlapped blocks of Q pixels in the horizontal dimension and S pixel in the vertical dimension, the number of blocks per sub-image is (N*M)/(Q*S) while per image is [3(NM/(Q*S(WM)] and the number of bits per block is [3*(Q*S)]*P. If, for example Q=S=4 and P=8, then the resulting size of each block is 384 bits. If the number of bits per channel is R=5, G=6, B=5 then the resulting size of each block per image is (4*4)*(5+6+5)=256 bits. The S3TC algorithm is able to compress such an amount of data by 6 times when R=8, G=8, B=8 and 4 times when R=5, G=6, B=5. 64 bits compose the resulting compressed block always sent to decompression stage. This number is the results of the coding steps described below assuming Q=S=4.
[0013] To sum up, operation of the S3TC algorithm may be regarded as comprised of the following steps:
[0014] i) Decompose the R G B image in non overlapped Q=4*S=4 blocks of R G B colors
[0015] ii) Consider the following block composed by 16 pixels each one composed by R, G and B color components:
[0016] Pij=R ij U G ij U B ij (this denotes the pixel at the ij position the R G B image, and U is the union operator)
(R11 G11 B11) (R12 G12 B12) (R13 G13 B13) (R14 G14 B14) (R21 G21 B21) (R22 G22 B22) (R23 G23 B23) (R24 G24 B24) (R31 G31 B31) (R32 G32 B32) (R33 G33 B33) (R34 G34 B34) (R41 G41 B41) (R42 G42 B42) (R43 G43 B43) (R44 G44 B44)
[0017] iii) Decompose the block above in three sub-blocks called sub-block R, sub-block G and sub-block B as shown hereinbelow, each block including only one color component:
R11 R12 R13 R14 sub-block R R21 R22 R23 R24 R31 R32 R33 R34 R41 R42 R43 R44 G11 G12 G13 G14 sub-block G G21 G22 G23 G24 G31 G32 G33 G34 G41 G42 G43 G44 B11 B12 B13 B14 sub-block B B21 B22 B23 B24 B31 B32 B33 B34 B41 B42 B43 B44
[0018] as shown in FIG. 1.
[0019] Specifically, FIG. 1 shows RGB blocks ordered in different planes, with a RGB block shown on the left and a corresponding de-composition shown on the right.
[0020] iv) Sort in ascending order each sub-block color
[0021] v) Detect the black color, which is a pixel made of R=0 and G=0 and B=0
[0022] vi) If the black color is not detected, then set a color palette made by
[0023] a. 1st color is the minimum value of sub-block R, minimum value of sub-block G, minimum value of sub-block B.
[0024] b. 2nd color is the maximum value of sub-block R, maximum value of sub-block G, maximum value of sub-block B
[0025] c. 3 rd is composed by (2*min R+max R)/3, (2*min G+max G)/3, (2*min B+max B)/3
[0026] d. 4 th is composed by (min R+2*max R)/3, (min G+2*max G)/3, (min B+2*max B)/3
[0027] vii) Otherwise, if black color is detected then set a color palette made by
[0028] a. 1 st color is minimum value of sub-block R, sub-block G, sub-block B where each of them must not be equal to zero (the black color component) at the same time
[0029] b. 2 nd color is maximum value of sub-block R, sub-block G, sub-block B
[0030] c. 3 rd is composed by (min R+max R)/2, (min G+max G)/2, (min B+max B)/2
[0031] d. 4 th is the black color that has R,G,B components equal to zero
[0032] viii) If black color is not detected, define the look-up color palette as
Look - up table = [ Min R , Int 1 R , Int 2 R , Max R ] [ Min G , Int 1 G , Int 2 G , Max G ] [ Min B , Int 1 B , Int 2 B , Max B ]
[0033] If black color is detected define the color palette as
Look - up table = [ Min R , Int 1 R , Max R 0 ] [ Min G , Int 1 G , Max G 0 ] [ Min B , Int 1 B , Max B 0 ]
[0034] ix) Associate the following 2 bits code (in boldface, under the palette) to each column of the above palette
Look - up table = [ Min R , Int 1 R , Int 2 R , Max R ] [ Min G , Int 1 G , Int 2 G , Max G ] [ Min B , Int 1 B , Int 2 B , Max B ] 00 01 10 11 Look - up table = [ Min R , Int 1 R , Max R 0 ] [ Min G , Int 1 G , Max G 0 ] [ Min B , Int 1 B , Max B 0 ] 00 01 10 11
[0035] x) For each Pij=R ij U G ij U B ij (where i ranges from 1 to Q=4 and j ranges from 1 to S=4) compute the Euclidean distance Dist between it and each look-up color as defined above in vi.a,b,c,d or vii.a,b,c,d depending if black color has been detected or not. Note that the difference is within a homologue color component (between R or G or B).
Dist 1 ={square root}(| R ij −Min R| 2 +|G ij −Min G| 2 +|B ij −Min B| 2 )
Dist 2 ={square root}(| R ij −Int 1 R| 2 +|G ij −Int 1 G| 2 +|B ij −Int 1 B| 2 )
Dist 3 ={square root}(| R ij −Int 2 R| 2 +|G ij −Int 2 G| 2 +|B ij −Int 2 B| 2 )
Dist 4 ={square root}(| R ij −Max R| 2 +|G ij −Max G| 2 +|B ij −Max B| 2 )
[0036] xi) For each Pij=R ij U G ij U B ij find the minimum distance among Dist 1 , Dist 2 , Dist 3 and Dist 4 . For example let this be Dist 1 .
[0037] xii) Send to a decoder process the code associated to the color enclosed in the look-up table that has the minimum distance. If it is Dist 1 then the code is 00.
[0038] xiii) The decoder receives for each Q*S block as shown in FIG. 2
[0039] a. 2 bits code for each Pij that are addresses to the look-up table
[0040] b. MinR MinG MinB
[0041] c. MaxR MaxG MaxB
[0042] xiv) If Min is received before Max by the decoder, then black has been detected by the encoder otherwise not
[0043] xv) As shown in FIG. 2, the decoder operates as described in steps vi or vii depending on black color detection
[0044] a. Int 1 R Int 1 G Int 1 B
[0045] b. Int 2 R Int 2 G Int 2 B
[0046] xvi) As shown in FIG. 2, the decoder addresses a look-up table with 2 bits code associated to each Pij and replaces it with the color stored in the look-up table color palette. Specifically ST, LUT, and CT indicate the source text, the look-up table, and the compressed text, respectively.
[0047] [0047]FIG. 3 shows how the data sent to the decoder are arranged in a bitstream and if the black color is not detected, while FIG. 4 shows the opposite case.
[0048] As stated before, the compression ratio is 6:1 or 4:1. This is because if colors are in R=8 G=8 B=8 format then 384 bits are coded with 64 (384/64=6) and if colors are in R=5 G=6 B=5 format then 256 bits are coded with 64 (256/64=4).
[0049] As shown in FIGS. 3 and 4, the sum of all the bits amounts to 64.
SUMMARY OF THE INVENTION
[0050] However satisfactory the prior art solution considered in the foregoing may be, the need is felt for alternative texture compression/decompression techniques. The aim of the present invention is thus to provide such an alternative technique.
[0051] According to the present invention such an object is achieved by means of a method having the features set forth in the claims that follow. The invention also encompasses the decoding process as well as corresponding apparatus in the form of either a dedicated processor or a suitably programmed general-purpose computer (such as a DSP). In that respect the invention also relates to a computer program product directly loadable into the memory of a digital computer and including software code portions for performing the method of the invention when the product is run on a computer.
[0052] In brief, the presently preferred embodiment of the invention differs, in one of its aspects, from the S3TC algorithm in the way the reference colors are selected to construct the look-up table. The way of choosing these colors is made adaptive and consists in creating groups of colors for each color component R,G,B and select at first a group from which a representative color for this group is derived. Preferably, each group is composed by any number of colors between 3 up to 15 members. For each of them the median color is chosen as the representative color of the group to which it belongs. For sake of clarity, the median of a set of numbers put in ascending order is the number located in the middle position of them.
[0053] For example if the set is (1, 3, 5, 6, 20) then the median is the 3 rd value (from right) and is equal to 5.
[0054] For each group, an error is computed as the sum of the absolute differences (SAD) between each group member and the representative (the median value of the group) color.
[0055] Still preferably, at least two different criteria are used to select the group first and then extract from this group a representative color.
[0056] The former is to select the group that minimizes the error as defined before, assuming each group comprised of the lower colors sorted in ascending order. The same applies for the groups comprised of the higher colors.
[0057] The latter accrues the error computed separately for the two groups in all possible combinations and then provides for finding the minimum of the composite error.
[0058] Groups that include only the minimum color or the maximum color are not considered during the processing which are, instead, the reference colors for S3TC.
[0059] The arrangement disclosed herein detects black colors. Also the encoding steps, the bitstream composition and the decoding steps are different if compared to S3TC.
BRIEF DESCRIPTIONS OF THE DRAWINGS
[0060] The invention will now be described, by way of example only, with reference to the annexed figures of drawing, wherein:
[0061] FIGS. 1 to 4 pertain to the prior as described above;
[0062] [0062]FIG. 5 shows R or G or B sub-blocks sorted from left to right in ascending order in a possible embodiment of the invention;
[0063] [0063]FIG. 6 shows examples of groups in respective sets as well as examples of computed errors;
[0064] [0064]FIGS. 7 and 8 show possible variants of the arrangement described herein; and
[0065] [0065]FIG. 9 is a block diagram of a pipeline arrangement to evaluate the performance of the compression and decompression techniques described herein.
DETAILED DESCRIPTION
[0066] The presently preferred embodiment of the invention differs, in one of its aspects, from the S3TC algorithm in the way the reference colors are selected to construct the look-up table. The way of choosing these colors is made adaptive and consists in creating groups of colors for each color component R,G,B and select at first a group from which a representative color for this group is derived. Preferably, each group is composed by any number of colors between 3 up to 15 members. For each of them the median color is chosen as the representative color of the group to which it belongs. For sake of clarity, the median of a set of numbers put in ascending order is the number located in the middle position of them.
[0067] For example if the set is (1, 3, 5, 6, 20) then the median is the 3 rd value (from right) and is equal to 5.
[0068] For each group, an error is computed as the sum of the absolute differences (SAD) between each group member and the representative (the median value of the group) color.
[0069] Still preferably, at least two different criteria are used to select the group first and then extract from this group a representative color.
[0070] The former is to select the group that minimizes the error as defined before, assuming each group comprised of the lower colors sorted in ascending order. The same applies for the groups comprised of the higher colors.
[0071] The latter accrues the error computed separately for the two groups in all possible combinations and then provides for finding the minimum of the composite error.
[0072] Groups that include only the minimum color or the maximum color are not considered during the processing which are, instead, the reference colors for S3TC.
[0073] The arrangement disclosed herein detects black colors. Also the encoding steps, the bitstream composition and the decoding steps are different if compared to S3TC.
[0074] An embodiment of the invention will now be described by using the approach previously adopted for describing the S3TC arrangement and assuming Q=S=4.
[0075] i) Decompose the R G B image in non overlapped Q=4 S=4 blocks of R G B colors
[0076] ii) Consider the following 4×4 block composed of 16 pixels each one composed by R, G and B components:
[0077] Pij=R ij U G ij U B ij (this again denotes the pixel at the ij position in the R G B image, where U is the union operator)
(R11 G11 B11) (R12 G12 B12) (R13 G13 B13) (R14 G14 B14) (R21 G21 B21) (R22 G22 B22) (R23 G23 B23) (R24 G24 B24) (R31 G31 B31) (R32 G32 B32) (R33 G33 B33) (R34 G34 B34) (R41 G41 B41) (R42 G42 B42) (R43 G43 B43) (R44 G44 B44)
[0078] iii) Decompose the block above in three sub-blocks called sub-block R, sub-block G and sub-block B each block including only a color component:
R11 R12 R13 R14 sub-block R R21 R22 R23 R24 R31 R32 R33 R34 R41 R42 R43 R44 G11 G12 G13 G14 sub-block G G21 G22 G23 G24 G31 G32 G33 G34 G41 G42 G43 G44 B11 B12 B13 B14 sub-block B B21 B22 B23 B24 B31 B32 B33 B34 B41 B42 B43 B44
[0079] iv) Sort in ascending order each sub-block color R, G, B as shown in FIG. 5. Each number is the position in ascending order that addresses each color component R,G,B
[0080] v) Define two sets, each set including some groups of color for each R, G, B component independently. The left-hand portion of FIG. 6 shows the yellow set and the red set as an example of such groups for a given color component. In the yellow set, each group includes an increasing number of colors starting from the minimum on the left and excluding the group with only the lowest color (marked with X). In the red set, each group includes a decreasing number of colors starting form the maximum on the right and excluding the group with only the highest color (marked with X).
[0081] vi) For each group, compute the error as the sum of absolute differences (SAD) between its median color and each color composing the group. Referring to the right hand portion of FIG. 6, Ei is such error associated to the yellow set (where i ranges from 1 to the number of groups belonging to yellow set) and ej (where j ranges from 1 to the number of groups belonging to red set) is the error associated to red set, where i or j is the index to address each group in the respective set
[0082] vii) Two sets of errors are computed, Ei and ej. Selection of the yellow group and red group (and then depending on which one is selected, the median is taken as the representative color) can occur in two ways:
[0083] a) the yellow group is the one that has the minimum error between all Ei's and the red group is the one that has the minimum error between all ej's
[0084] b) all possible combinations of Ei+ej are computed first and then the global minimum value is found. This will select at the same time—and not separately as before—a yellow and red group that has the error that minimizes the Ei+ej number. For example E 7 +e 11 being the minimum implies the selection of 4th element as min_median reference and 14th element as max_median reference for next encoding steps
[0085] viii) The color representatives as defined in step vii) will be used to set the encoding step.
[0086] If the black color is detected, step vi) is modified in such a way that each group of color does not include the black.
[0087] The basic scheme described in the foregoing lends itself to a numbers of variants.
[0088] A first variant has only two groups of colors of 3 and 5 elements as shown in FIG. 7.
[0089] Depending on the criteria a) and b) assumed in the previous section vii two additional variants can be defined.
[0090] In particular, referring to FIG. 7, in the first of these additional variants:
[0091] If E 3 <=E 5 min_median reference 1 =element 2 , else min_median reference 1 =element 3 ,
[0092] If e 3 <=e 5 max_median reference 2 =element 15 else max_median reference 2 =element 14
[0093] In the second variant:
[0094] If minimum is E 3 +e 3 then min_median reference 1 =element 2 and max_median reference 2 =element 15
[0095] If minimum is E 3 +e 5 then min_median reference 1 =element 2 and max_median reference 2 =element 14
[0096] If minimum is E 5 +e 3 then min_median reference 1 =3 and max_median reference 2 =element 15
[0097] If minimum is E 5 +e 5 then min_median reference 1 =3 and max_median reference 2 =element 14
[0098] A further additional variant takes always as min_medianreference 1 equal to the second element and as max_median_reference — 2 equal to the 15 th , while another additional variant takes always as min_median reference 1 the 3 rd element and max_median as reference 2 the 14 th as shown in FIG. 8 where the first row is related to STM-TC3 and the second is related to STM-TC 5.
[0099] At the end of above described variants, each one produces as a result two reference colors named:
[0100] 1) min_medianR U min_medianG U min_medianB
[0101] 2) max_medianR U max_medianG U max_medianB
[0102] where U is the union operator grouping them as a whole pixel.
[0103] Next, the proposed method computes a value called length as follows.
[0104] If the black colour (which is a pixel made of R=0 and G=0 and B=0) has not been detected:
Length — R =(max_median R −min_median R )/6
Length — G =(max_median G −min_median G )/6
Length — B =(max_median B −min_median B )/6
Length={square root}(|Length — R| 2 +|Length — G| 2 +|Length — B| 2 )
[0105] where max_medianR,G,B and min_medianR,G,B are the representative colors for each selected group belonging to the red and yellow sets.
[0106] This is the maximum quantization error the method can compute when Pij colors are quantized during the encoding step, here described.
[0107] If the black color is not detected for each Pij=R ij U G ij U B ij (where i range is from 1 to Q=4 and j range is from 1 to S=4) compute the Euclidean distance
Dist — ij ={square root}(| R ij −min_median R| 2 +|G ij −min_median G| 2 +|B ij −min_median B| 2 )
[0108] Now the encoder quantizes each color as follows:
[0109] if Dist_ij<=(Length) send to the decoder the code 00
[0110] if (Length)<Dist_ij<=3*Length send to the decoder the code 01
[0111] if (3*Length)<Dist_ij<=5*Length send to the decoder the code 10
[0112] if Dist_ij>5*Length send to the decoder the code 11
[0113] When a block is encoded, the decoder receives a 2 bits code for each Pij as above defined, plus min_medianR U min_medianG U min_medianR plus length_R, length_G, length_B
[0114] Conversely, if the encoder detects the black color, then
Length — R =(max_median R −min_median R )/4
Length — G =(max_median G −min_median G )/4
Length — B =(max_median B −min_median B )/4
Length={square root}(|Length — R| 2 +|Length — G| 2 +|Length — B| 2 )
[0115] for each Pij=R ij U G ij U B ij (where i range is from 1 to Q=4 and j range is from 1 to S=4) quantize them as follows
compute Dist ij ={square root}(|R ij −min_median R| 2 +|G ij −min_median G| 2 +|B ij −min_median B| 2 )
[0116] if R ij =Gij=Bij=0 send to the decoder the code 00
[0117] else if R ij or Gij or Bij not equal to 0
[0118] if Dist ij<=(Length) send to the decoder the code 01
[0119] if (Length)<Dist ij<=3*Length send to the decoder the code 10
[0120] if (3*Length)<Dist ij send to the decoder the code 11
[0121] When a block is encoded the decoder receives 2 bits code for each Pij as above defined, plus min_medianR U min_medianG U min_medianR after length_R, length_B, length_B
[0122] If decoder receives min_medianR U min_medianG U min_medianR before length_R, length_B, length_B this means that the black color is not detected so the output colors will be
[0123] if the code is 00
[0124] Rij=min_medianR
[0125] Gij=min_medianG
[0126] Bij=min_medianB
[0127] if the code is 01
[0128] Rij=min_medianR+2*length_R
[0129] Gij=min_medianG+2*length_G
[0130] Bij=min_medianB+2*length_B
[0131] if the code is 10
[0132] Rij=min_medianR+4*length_R
[0133] Gij=min_medianG+4*length_G
[0134] Bij=min_medianB+4*length_B
[0135] if the code is 11
[0136] Rij=min_medianR+6*length_R
[0137] Gij=min_medianG+6*length_G
[0138] Bij=min_medianB+6*length_B
[0139] If the decoder receives Min_medianR U min_medianG U min_medianR after length_R, length_B, length_B it means that black color is detected so the output colors will be
[0140] if the code is 00
[0141] Rij=0
[0142] Gij=0
[0143] Bij=0
[0144] if the code is 01
[0145] Rij=min_medianR
[0146] Gij=min_medianG
[0147] Bij=min_medianB
[0148] if the code is 10
[0149] Rij=min_medianR+2*length_R
[0150] Gij=min_medianG+2*length_G
[0151] Bij=min_medianB+2*length_B
[0152] if the code is 11
[0153] Rij=min_medianR+4*length_R
[0154] Gij=min_medianG+4*length_G
[0155] Bij=min_medianB+4*length_B
[0156] The various arrangements described in the foregoing have been applied to the following standard images by using two formats: RGB 565 and RGB 888, where 5, 6 or 8 is the number of bits per color channel.
[0157] 1. 256×256 (horizontal×vertical size dimension)
[0158] Abstrwav
[0159] Chapt
[0160] Forest
[0161] Intel
[0162] Pixtest
[0163] Reference
[0164] Teleport
[0165] Topsmap
[0166] 2. 512×512 (horizontal×vertical size dimension)
[0167] Donut
[0168] 3. 512×1024 (horizontal×vertical size dimension)
[0169] Face
[0170] 4. 640×480 (horizontal×vertical size dimension)
[0171] Balloon
[0172] 5. 1024×768 (horizontal×vertical size dimension)
[0173] Yahoo
[0174] These pictures are a representative set on which texture compression is typicaly applied.
[0175] All the pictures are in true-color format or 888, while the 565 format is obtained from the 888 format by truncating the 323 lowest bits of the 888 pictures. Alternative truncating methods can be used to go from 888 to 565 such as rounding to nearest integer, Floyd-Steinberg dithering etc. These do not imply any changes in the arrangement disclosed herein.
[0176] To evaluate the performance of each arrangement, visual assessments and objective measures can be performed. In particular two parameters are taken as reference measures:
[0177] mean square error (MSE), and
[0178] peak signal/noise ratio (PSNR) for each RGB channel.
[0179] [0179]FIG. 9 shows how the measures are taken within the simulation environment.
[0180] Input images IS in the 888 format (called Source888) are converted at 200 into the 565 format (called Source565), then compressed at 201 and further decompressed at 202 to the 565 format. These are back converted at 203 into the 888 format to generate a first set of output images OS′ (also called Decoded888).
[0181] The Source-565 images from block 200 are back converted into 888 at 204 to generate a second set of output images OS″ to be used as a reference (called Source565to888).
[0182] A first set of PSNR values (called PSNR 888) are computed between the Source 888 IS and the Decoded888 OS′ images. A second set of PSNR (called PSNR 565) values are computed between the Source565to888 OS″ and the Decoded888 OS′ images.
[0183] In particular, 565 images are back reported to 888 by simple zero bit stuffing of the 323 least significant positions.
[0184] How the Source888 IS images are converted to the 565 format and back to the 888 foamt corresponds to techniques that are well known to the experts in this area and do not need to be described in detail here:
MSE =(Σ| Pij−Paij| 2 )/( w*h )
[0185] where:
[0186] Pij=source color
[0187] Paij=processed color
[0188] w, h=image width, height
PSNR= 10 log 10 [(2 bpp −1) 2 /MSE ]
[0189] where:
[0190] bpp=bit per color
[0191] The results show that all the variants of the solution disclosed herein perform significantly better than S3TC in most tests.
[0192] Of course, the underlying principle of the invention remaining the same, the details and embodiments may vary, also significantly, with respect to what has been described and shown by way of example only, without departing from the scope of the invention as defined by the annexed claims. | A method for texture compressing images having a plurality of color components (R, G, B) includes defining color representatives for use in encoding by defining groups of colors for each color component (R,G,B), and selecting a representative median color for the group. Each group ideally includes 3 to 15 increasing colors. The method includes computing, for each group, an error between each member of the group and the representative median color of the group. Typically, the error is computed as the sum of the absolute differences (SAD) between each member of the group and the representative median color of the group. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a measurement while drilling tool. More specifically, but without limitation, this invention relates to an apparatus and method for telemetering a down hole parameter from a well.
Operators drill wells many thousands of feet in the search for hydrocarbons. The wells are expensive and take a significant amount of time to plan. Operators find it important to obtain data about the various subterranean reservoirs once the actual drilling begins. Thus, measurement while drilling (MWD) tools have been developed that gather information about the subterranean reservoirs and telemetry the data to the surface. Engineers and geologist can then use this data in an effort to understand the formations and make plans on completion, sidetracking, abandoning, further drilling etc.
MWD tools are expensive tools due to their complexity. The tools are designed for a lifetime of 5-7 years, and the tools are routinely made of expensive materials and electronics which require a lot of maintenance by highly trained personnel. Typically, service companies have geographically positioned regional maintenance facilities that perform these tasks. As the use of MWD and LWD tools expanded, several problems have become evident. One problem is that maintenance requires very high levels of training. Mean time between failures (MTBF) has become the standard measurement for evaluating the reliability of the MWD technology, and a central question is when will the tool fail. Another problem is that the maintenance facilities require large spaces and expensive testing equipment. It is not uncommon for a MWD tool to spend as much time traveling to and from these maintenance facilities as it does at the wellsite. In one study, it was found that a MWD tool string spends less than 90 days a year in a well, and the maintenance and logistics cost of a MWD tool can amount to 50% of the annual expense of the system.
Therefore, it is an object of the present invention to reduce the maintenance and repair time of MWD tools. It is also an object of the present invention to reduce the maintenance and repair cost. It is also an object to manufacture a tool that is less expensive to build, less complex and have higher reliability. These objects, and many others, will be met by the following disclosure.
SUMMARY OF THE INVENTION
An apparatus for telemetering a down hole parameter from a well is disclosed. The apparatus comprises a cylindrical housing having a bore there through. The apparatus further comprises an annular main valve positioned within the bore, with the main valve having a center of axis, and wherein the main valve is in a funnel shape having a tubular inlet and tubular outlet, and a restrictor member concentrically disposed within the bore of the cylindrical housing, wherein the restrictor member is aligned with the center of axis, the restrictor member configured to define an annular passage with the main valve. The apparatus also includes: a hydraulic circuit control pressure passage means for supplying hydraulic pressure to the main valve; control means, operatively associated with the restrictor member, for controlling pressure to the main valve; and a solenoid control valve assembly for activating the control means. It should be noted that the solenoid control valve assembly may also be referred to as the magnetic control valve assembly.
In one preferred embodiment, the solenoid control valve assembly comprises a controller for emitting an electrical signal, a coil receiving the electrical signal in order to energize the coil and generating a magnetic field, a solenoid static pole receptive to the generated magnetic field, and a solenoid moving pole responsive to the magnetic field so that the solenoid moving pole moves in a direction towards the solenoid static pole. Also, the control means may comprise a shaft operatively associated with the solenoid moving pole, a ball engageable with the shaft, and a ball seat configured to sealingly engage with the ball. The restrictor member may include a restrictor housing having a bolt that is selectively movable within the restrictor housing to vary the size of the annular passage. The restrictor housing further includes an annular screen for allowing passage of a fluid into an annular cavity.
The cylindrical housing is configured to have an annular flow area for the hydraulic circuit control passage means that communicates pressure from the pressure means to the main valve through the cylindrical housing. In one preferred embodiment, the hydraulic circuit control passage means includes a passage through said static pole and through the ball seat in order to act against the main valve. Additionally, as the coil de-energizes, the shaft, via the moving pole, returns and the ball is allowed to return to seal against the ball seat so that the main valve moves from a first position to a second position thereby enlarging the annular passage.
A method of communicating a down hole parameter is also disclosed. The method comprises providing a down hole apparatus, the down hole apparatus including: a cylindrical housing having a bore; an annular main valve positioned within the bore, the main valve having a center of axis, and wherein the main valve has a first end disposed within the bore and an enlarged second end, and wherein the main valve is movable from a first position to a second position; a restrictor member concentrically disposed within the bore of the enlarged second end of the main valve, wherein the restrictor member being aligned with the center of axis, and wherein the main valve has the first end disposed within the bore and the enlarged second end configured to form an annular passage about the restrictor member; hydraulic circuit control pressure passage means for supplying hydraulic pressure to the main valve.
The method further includes flowing the drilling fluid through the bore, emitting an electrical signal with a controller, and receiving the electrical signal with a coil. The method further includes generating a magnetic field, receiving the magnetic field at a solenoid static pole so that the solenoid static pole is magnetized, and moving a solenoid moving pole in response to the generated magnetic field in the direction of the solenoid static pole. The method further includes moving a shaft, the shaft being operatively attached to the solenoid moving pole. The method further comprises displacing a ball that is seated within a ball seat, allowing pressure from an annular cavity to pass through a hydraulic circuit control pressure passage means which includes through the ball seat and displace the main valve from the first position to the second position, and decreasing the annular passage between the main valve and the restrictor member thereby causing a pressure pulse to be created within the bore of the cylindrical housing indicative of the downhole parameter.
In one preferred embodiment, the step of flowing the drilling fluid through the bore includes channeling the turbulent flow of the drilling fluid through the enlarged second end of the main valve and into the annular passage. The method may further comprise emitting a second electrical impulse signal with the controller, terminating the second electrical signal to the coil so that the magnetic field is terminated, moving the ball onto the ball seat by the pressure within the annular cavity via the pressure within the cavity, terminating the flow through the hydraulic circuit control pressure passage means and moving the main valve from the second position to the first position via the pressure within the bore of the cylindrical housing.
An advantage of the present invention is that the design allows for fewer parts and a shorter tool length. Another advantage is that the components of the system are designed in modules, wherein the modules can be replaced with a new module. Another advantage is that no field service technicians are needed, eliminating maintenance problems. Because the tool is designed to go straight from manufacturing to the rig, much higher utilization rates will be achieved.
A feature of the present invention includes the annular main valve, wherein the funnel shape of the main valve contains all violent, turbulent flow caused by pulsers, and in doing so, it contains all the erosion within its surface that is made of very hard ceramic or tungsten carbide material. Another feature is the ball control valve that utilizes a poppet valve constructed of a separate ball and shaft that allows the ball to seat perfectly by eliminating concentricity issues. Another feature is that the present design is very well suited for fluids with high solid contents.
Yet another feature is the annular screen element that allows a large inlet area for a relatively small axial height, thus allowing the overall length to be significantly shorter than current designs. Still yet another feature is that the annular solenoid doughnut shape provides the geometry best suited to minimize overall valve length. Another feature is the annular control valve. Still yet another feature is the control valve ball seat, pilot driven main valve, and exit that are nearly aligned to minimize axial packaging requirements. Thus, the shortest (minimum axial length) possible valve is obtained.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a perspective view of the drill collar housing containing the down hole apparatus and drill bit.
FIG. 1B is a perspective view of the drill bit and drill collar housing seen in FIG. 1A taken from view I-I.
FIG. 2 is a cross-sectional view of the drill collar housing containing the down hole apparatus seen in FIG. 1A taken along line A-A of FIG. 1B .
FIG. 3 is a cross-sectional view of the drill collar housing containing the down hole apparatus seen in FIG. 1A taken along line B-B of FIG. 1B .
FIG. 4A is a cross-sectional view of the drill collar housing containing the down hole apparatus seen in FIG. 1A taken along line C-C of FIG. 1B .
FIG. 4B is an enlarged view of the pressure bulkhead seen in FIG. 4A .
FIG. 5 is an enlarged view of the detail area “D” seen in FIG. 2 .
FIG. 6 is an enlarged view of the detail area “E” seen in FIG. 2 .
FIG. 7 is an enlarged view of the detail area “F” seen in FIG. 6 .
FIG. 8 is an enlarged view of the detail area “D” seen in FIG. 2 .
FIG. 9 is a schematic representation of the down hole apparatus being used in a well bore.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1A , a perspective view of the drill collar housing 2 containing the down hole apparatus and drill bit 4 . As understood by those of ordinary skill in the art, the drill collar housing 2 is connected to the drill bit 4 . FIG. 1B is a perspective view of the drill collar housing seen in FIG. 1A taken from view I-I. More specifically, FIG. 1B depicts the lines A-A, B-B, and C-C which will described in more detail later in the application.
Referring now to FIG. 2 , a cross-sectional view of the drill collar housing containing the down hole apparatus, drill collar housing 2 and drill bit 4 seen in FIG. 1A taken along line A-A of FIG. 1B will now be described. It should be noted that like numbers appearing in the various drawings refer to like components. More specifically, FIG. 2 depicts the battery and electronics section 6 to power and control the tool. The electronics section 6 includes a controller for processing collected down hole data, storing the data and generating outputs to the various electronic components. FIG. 2 also depicts the sensors 8 to make measurements, such as directional survey sensors and/or gamma ray sensors. A communications port 10 is provided in order to talk to the tool before and after being used in the drill string. The pressure housing 12 is shown, wherein the pressure housing 12 is used to package sensors, batteries, and electronics. FIG. 2 also depicts the drill collar housing 14 that connects to the remainder of the drill string. FIG. 2 also depicts the detail ovals D, E and F which will be discussed later in the application. The down hole pulser apparatus is seen generally at 16 , and is generally contained within the detail box D.
FIG. 3 is a cross-sectional view of the drill collar housing 2 taken along line B-B of FIG. 1B . FIG. 3 depicts the battery and electronics section 6 , the pressure housing 12 and the communications port 10 , as well as the downhole pulser apparatus 16 (hereinafter pulser 16 ).
FIG. 4A is a cross-sectional view of the drill collar housing 2 containing the pulser 16 taken along line C-C of FIG. 1B . The pressure bulkhead 18 is also shown in FIG. 4A . FIG. 4B is an enlarged view of the pressure bulkhead 18 seen in FIG. 4A . The pressure bulkhead 18 is used to provide electrical power to the solenoid, but isolate internals of the pressure housing 12 from fluid pressure exposure. The pressure bulkhead 18 contains a single conductor with first prong 20 that is connected to the battery and electronic section 6 and a second prong 22 that connects to the solenoid coil that will be described in greater detail later in the application. There are two pressure bulkheads 18 (one is not shown), one for each electrical termination of the solenoid coil.
Referring now to FIG. 5 , an enlarged view of the detail area “D” as seen in FIG. 2 , and in particular the pulser 16 seen in FIG. 2 , will now be described. FIG. 5 depicts the screen and restrictor housing 24 with the annular screen 26 disposed therein. As those of ordinary skill in the art recognize, the drilling fluid is pumped down the drill string, as denoted by arrow “AA”. The screen 26 allows the liquid part of the drilling fluid flow to pass and keeps the larger particles from going into the hydraulic circuit control passage and the solenoid control valve assembly, as will be more fully described later. FIG. 5 also depicts the annular control housing 28 which provides the large annular area for the hydraulic circuit control passage that feeds the main valve 30 with drilling fluid, as will be more fully explained. The main valve 30 contains an outer diameter portion and an inner diameter portion. FIG. 5 shows the connection point of the screen 26 and restrictor housing 24 and the annular control housing 28 at threads 34 . FIG. 5 further depicts the restrictor bolt 36 which supports the main valve restrictor 37 and provides a means to adjust the axial position used to set the size of the pressure pulse. As seen in FIG. 5 , the main valve 30 is in a funnel shape. In other words, the first end 38 has a larger inner diameter than the second end 40 , and wherein end 38 acts as a tubular inlet and end 40 acts as a tubular outlet for the drilling fluid.
The restrictor housing 24 holds the restrictor 37 and screen 26 and provides a passage for the drilling fluid from the center of the drill pipe to the annulus cavity between the restrictor 37 and the main valve 30 . The restrictor 37 provides the restriction on the inner conical surface of the main valve for the flow of the drilling fluid. If the main valve 30 moves forward enough, the main valve 30 could contact the restrictor 37 and completely shut off the flow of the drilling fluid. In the embodiment shown, however, this could not happen because there is a physical stop upstream of the main valve that stops it from contacting the restrictor. As will be more fully explained later in the application, the solenoid control valve assembly opens and closes and causes flow or no flow through the hydraulic circuit control passage. The restrictor 37 will be attached to the annular control housing 28 as shown in FIG. 5 . The drilling fluid coming down the bore of the drill pipe will divert about the diverter, out of the opening “O”, and back into the bore of the main valve 30 .
FIG. 5 further depicts the solenoid control valve assembly which includes the solenoid static pole 42 , and wherein the solenoid static pole 42 contains certain cavities, seen generally at 44 that contain hydraulic oil. The solenoid static pole 42 is operatively associated with the solenoid coil 46 , and wherein the solenoid coil 46 is connected to the solenoid coil housing 48 . As shown in FIG. 5 , the solenoid coil housing 48 is positioned within the drill collar housing 2 . The pulser 16 also includes the main valve bearing housing 50 , and wherein the main valve bearing housing 50 is operatively connected to the annular control housing 28 . The main valve upper bearing 52 and the main valve lower bearing 54 are adjacent and cooperate with the main valve bearing housing 50 , and wherein the bearings 52 and 54 serve the purpose of positioning the main valve 30 concentric within the main valve bearing housing 50 . The solenoid moving pole 56 is shown disposed between the main valve bearing housing 50 and the poppet shaft 58 . The solenoid coil 46 is the winding that when current flows through it, it creates a magnetic field in the iron-rich materials that form a path around the coil 46 . The magnetic field produces a magnetic force that attracts the solenoid moving pole 56 to the solenoid static pole 42 . As seen in FIG. 8 , lack of this force causes the axial gap “G” to open.
Returning to FIG. 5 , the restrictor sleeve 60 covers the axial gap between the restrictor 37 and the restrictor bolt 36 . The restrictor 37 is made of very hard material such as ceramic or tungsten carbide. Also, FIG. 5 depicts the pressure pipe plug 64 that is used to fill and isolate the control valve cavity 44 which is filled with clean hydraulic fluid. The rubber compensating sleeve 66 compensates for hydraulic fluid contraction and expansion within cavity 44 due to temperature and pressure.
It should be noted that as shown in FIG. 5 , the most preferred embodiment depicts a ball on the left side and the right side as well as a shaft on the left side and the right side that are attached to one moving pole (which is cylindrical). Only the right side ball and shaft have been described.
Referring now to FIG. 6 , an enlarged view of the detail area “E” seen in FIG. 2 will now be described. This view shows, among other things, the main valve bearing housing 50 , and slidably adjacent to it, the solenoid moving pole 56 . The main valve bearing 54 is disposed between the main valve 30 and the main valve bearing housing 50 . FIG. 6 also depicts the cavity 44 . The first end 38 of main valve 30 depicts the enlarged inner diameter while the second end 40 depicts the smaller inner diameter. Thus, main valve 30 is in the shape of a funnel. The shaft 58 has a bottom 67 a that will engage with the top end of the set screw as will be explained later in the application.
FIG. 7 is an enlarged view of the detail area “F” seen in FIG. 6 . The control valve ball 68 is positioned adjacent the control valve poppet shaft 58 , and wherein the ball 68 is separate from shaft 58 and the ball 68 will seal-off in the seat 70 . A control valve shaft sleeve 72 is pressed onto the control valve poppet shaft 58 , and the control valve poppet bearing 74 is disposed about sleeve 72 . A control valve wiper and seal 75 is also included. The control valve return spring 76 pushes the moving pole 56 back into its lower position when the current in the solenoid is removed and the magnetic field is turned off. The spring 76 engages the retaining ring 78 . The setscrew 80 is used to adjust the critical gap of the solenoid that defines how far the ball 68 moves. The set screw 80 that is threaded into the moving pole will engage with the bottom 67 a of the shaft 58 so that movement of the moving pole 56 moves the set screw 80 which in turn engages and moves the shaft 58 .
As seen in FIG. 7 , the control valve ball guide rails 84 contain the control valve ball 68 by providing for a large unobstructed inlet flow area when the ball is unseated. The arrows “BB” depicts the hydraulic circuit control passageway which allows the pressure to act against the main valve 30 .
It should be noted that FIGS. 5 , 6 , 7 show the situation where the shaft 58 has displaced the ball 68 due to the magnetic movement means, and in particular, the solenoid moving pole 56 . As noted earlier, the shoulder 67 a is engaged with moving pole 56 which causes shaft 58 to move upward. FIG. 8 is an enlarged view of the detail area “D” seen in FIG. 2 . In FIG. 8 , the ball has resumed its position on the control valve seat 70 so that the hydraulic pressure is no longer communicated through the hydraulic circuit control pressure passage “BB” and against the main valve 30 (i.e. the hydraulic circuit control pressure passageway is closed), which is due to the termination of the magnetic field. In other words, in FIG. 8 , the solenoid moving pole 56 has returned to its initial position. When the coil is de-energized, the control valve ball 68 seals against the seat 70 , and the shaft 58 is in its lowered position due to the de-energized coil. The shaft 58 has returned to this lowered position due to the biasing action of spring 76 . Hence, FIG. 8 depicts a view of the detail area “D” seen in FIG. 2 , wherein the ball 68 is seated on the seat 70 . The annular passage is denoted by the letters “AP”.
Referring back to FIGS. 5 , 6 , and 7 collectively, the pressure profile within the pulser 16 will now be described. P 1 denotes the pressure of the drill pipe fluid flow just upstream or at the inlet of the pulser 16 . P 2 is the pressure of the annular cavity AC 1 filtered by the screen 26 . P 3 signifies the pressure of the annular cavity AC 2 formed by the main valve 30 . P 4 is the pressure of the primary drilling fluid flow in the bore of the main valve 30 downstream from the restrictor 37 . Also, P 5 is the oil pressure of the internal cavities 44 of the solenoid control valve assembly.
According to the teachings of the present invention, there are two (2) states for the pulser 16 . In the first state, there is no flow through the hydraulic circuit control passage “BB”. The control valve ball 68 seals against the control valve ball seat 70 and prevents any flow through the hydraulic circuit control passage. The main valve 30 is pushed downstream against the mechanical stop 86 (seen expressly in FIG. 5 ). In this state, there is a minimum of pressure drop through the pulser 16 . This minimum pressure drop, which has been found to be usually less than 100 psi, is the hydraulic power used to drive the main valve's 30 movement to the upward (restricted) position. The annular cavity AC 2 of the main valve 30 has a pressure P 3 , which equals its bore pressure P 4 .
In the second state, there is flow through the hydraulic circuit control passage “BB”. The flow goes through the screen 26 , then past the control valve ball 68 and ball seat 70 and finally, through a hole 88 in the main valve 30 . The opening area of the control valve ball 68 and ball seat 70 of the solenoid control valve assembly is much larger than the hole 88 through the main valve 30 . When flow begins in the hydraulic circuit control passage “BB, there is a pressure increase in the annular cavity AC 2 of the main valve, that is, P 3 increases to the value of P 2 . That is, the annular pressure of the main valve 30 now experiences the upstream inlet pressure of the pulser 16 . This pressure increase causes the main valve 30 to move forward. As the main valve 30 moves forward, it closes the distance (space) between the main valve 30 and the restrictor 37 (i.e. the area of the annular passage decreases). This increases the pressure drop across the tool and more specifically through the restriction between the restrictor 37 and the main valve 30 . This causes a pressure pulse that travels at the speed of sound upstream to the drilling rig. The main valve 30 then stops movement as it hits the upstream physical stop 90 , which is the radial end of the annular control housing 28 .
In operation, the solenoid control valve assembly starts operation in the closed position (i.e. the first state). The control flow through the hydraulic circuit control passage “BB” is shut-off. The net pressure on the main valve 30 is biased downward and so the main valve 30 rest on the downstream stop 86 . As understood by those of ordinary skill in the art, the electronics encode sensor data into pressure pulses. Also as well understood by those of ordinary skill in the art, there are many algorithms to encode the sensor data. When it is time to send a pulse, the electronics (controller) send the necessary current and voltage to the solenoid coil 46 , which pulls in the moving pole 56 to stop against the static pole 42 .
The moving pole 56 pushes the poppet shaft 58 , which pushes the ball 68 off the sealing seat 70 . As mentioned earlier, this allows a free flow through the hydraulic circuit control passage BB, which is through the screen 26 , through the annular space AC 1 , through the ball seat 70 , and past the poppet shaft 58 , into the annular cavity AC 2 of the main valve in order for the hydraulic pressure to act against the radial surface “S” (on the outer diameter portion of the main valve 30 ). This control flow is restricted through the small exit hole 88 of the main valve 30 resulting in the system pressure drop being experienced in the AC 2 . This flow provides an increase in pressure in the annular cavity AC 2 of the main valve 30 , which creates an imbalance and starts moving the main valve 30 upstream. This movement continues until the main valve 30 hits the up-hole physical stop 90 . When the movement stops, there is a tighter restriction in the annular passage “AP” i.e. the flow area between the main valve 30 and the restrictor 37 . This restriction causes an increase in pressure above the tool, which can be seen at the surface. After a short time interval (anywhere from 1/10 of a second or greater, depending on the code format), the electronics shuts off the current to the solenoid, which allows the moving pole 56 to return to its un-energized state using the spring force 76 . This action shuts-off flow through the hydraulic circuit control passage “BB”, since the ball 68 seats again on the seat 70 . The system is again back to the original first state. The main valve 30 then returns to the original position due to the force of the drilling fluid moving down the drill string.
Referring now to FIG. 9 , a schematic representation of the downhole apparatus being used in a well bore 100 will now be described. Hence, the bit 4 , which is connected to the drill collar housing 2 , has drilled the well bore 100 , and the operator is performing measurement while drilling operations. A drill string 102 is attached at one end to the rig 104 and at the other end is connected to the drill collar housing 2 (as noted earlier, the down hole apparatus 16 is positioned within the drill collar housing). The fluid flow of the drilling fluid within the well bore 100 is shown by the arrows “AA”, which is known as circulating. As taught by the present disclosure, the downhole sensors are collecting data, and the data is being processed down hole, and ultimately, the information is telemetered via pressure pulses through the fluid column to the surface.
Although the present invention has been described in terms of specific embodiments, it is anticipated that alterations and modifications thereof will no doubt become apparent to those skilled in the art. It is therefore intended that the following claims be interpreted as covering all such alterations and modifications as fall within the true spirit and scope of the invention. | An apparatus for telemetering a downhole parameter from a well. The apparatus comprises a housing having a bore. The apparatus further comprises an annular main valve with an enlarged end positioned within the bore, with the main valve having a center of axis. A restrictor is concentrically disposed within the bore, the restrictor configured to define an annular passage with the main valve. The apparatus also includes: a pressure device for supplying hydraulic pressure to the main valve; a control valve, operatively associated with the restrictor member, for controlling pressure to the main valve; and a solenoid control valve assembly for activating the control valve. In one preferred embodiment, the solenoid control valve assembly comprises a controller for emitting an electrical signal, a coil that receives the electrical signal and generates a magnetic field, a solenoid static pole receptive to the generated magnetic field, and a solenoid moving pole responsive to the magnetic field so that the solenoid moving pole moves in a direction towards the solenoid static pole. A method for communicating a downhole parameter is also disclosed. | 4 |
FIELD OF THE INVENTION
The invention relates to a filter construction of the sort which is adapted for venous installation, generally for femoral-vein and/or for jugular-vein installation, for enhanced assurance that a blood clot of lethal size will not enter. the heart. More particularly, the invention relates to such a filter for installation in the inferior vena cava, sometimes known as a vena-cava filter, or merely as a caval filter.
BACKGROUND OF THE INVENTION
Vena-Cava filters have been known and their use has been reported for more than twenty years, and the Review Article of Becker, et al., entitled "Inferior Vena Cava Filters--Indications, Safety, Effectiveness", Arch. Intern. Med.--Vol. 152, October 1992, acknowledges the commercial existence of at least six competitive varieties and provides an extensive bibliography of relevant papers. It suffices to indicate that these prior and current filter structures rely on guide-wire piloting techniques of installation but must be removed within 48 hours if they are not to become so trapped by tissue growth within the vein as to become potentially destructive of vein tissue should they be later removed. As a consequence, on many occasions, such filters have often had to stay in place, as a permanent fixture within the patient.
An expandable filamentary-mesh filter, made by Angiocor s.a.r.l. of Lille, France is an attempt to avoid this problem of wall-tissue growth, using mechanically actuated expansion of multiple helices, wherein the helices are of plastic filamentary material.
Other prior art vascular filter devices are disclosed in FR-A-2580504 and U.S. Pat. No. 4,662,885. Reference may also be made to U.S. Pat. No. 4,723,549 and EP-A-0377749.
BRIEF STATEMENT OF THE INVENTION
It is an object of the invention to provide an improved filter structure of the character indicated.
Another object is to provide such a filter construction that will not promote vein-tissue growth therein and which therefore can be safely removed after it has served its purpose, even though the time of its installation has greatly exceeded the time within which other filters have had to be removed if tissue damage was to be avoided.
A specific object is to provide a filter construction for filtration of venous flow within a living body, wherein an inflatable balloon is adapted upon inflation to so partially occlude the inferior vena cava as to pass venous flow without clots of pulmonary-artery or heart-threatening magnitude.
It is also a specific object to provide a filter construction which involves no wire or other metal contact with vein tissues when installed in a femoral vein.
Another specific object is to provide an inflatable filter construction which is installed in deflated state and which relies on pressure-fluid inflation to establish vein-filtering action.
A further specific object is to provide, in conjunction with a vena-cava filter, an option to inject tracer or contrast fluid, or a thrombolytic agent, into the filter-protected vein at a location of proximal (i.e. upstream) offset from the filter; more specifically, it is an object to provide for such angular distribution of fluid injection as to establish circumferentially diffused introduction of thrombolytic agent which can directly act on any incipient thrombus accumulation at the filter, thereby clearing the filter of thrombi.
The invention achieves the foregoing objects and provides further advantageous features in an inflatable balloon construction at or near the distal end of an elongate flexible multiple-lumen core. The balloon is suitably configured in a preferred embodiment for femoral-vein insertional installation; and in another embodiment the balloon is suitably configured for jugular-vein insertional installation. In both embodiments, the balloon is deflated prior to insertion; it is configured so that when inflated it becomes a filter when properly positioned in the vein, and it may simply be deflated for removal purposes. Installation may proceed pursuant to guide-wire techniques commonly used for catheter installation. Each of the indicated two embodiments is described for the case of additionally providing for injection of a tracer or a thrombolytic agent at a location in the vein at proximal (i.e. upstream) offset from the region of filter action.
Exemplary embodiments of the invention will hereinafter be described in detail in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified and somewhat schematic diagram to show the installed location of a first inflatable/deflatable embodiment of the invention;
FIG. 2 is an enlarged view in perspective of the operative filtering distal end of the embodiment of FIG. 1 in inflated condition, the view being partly broken away to reveal internal features;
FIG. 3 is a greatly enlarged sectional view at 3--3 in FIG. 2;
FIG. 4 is a similar but less enlarged sectional view at 4--4 in FIG. 2;
FIG. 5 is a view similar to FIG. 4, for the deflated condition;
FIG. 6 is a right section of a moulding element for dip-moulding in manufacture of the inflatable element of FIG. 2;
FIG. 7 is a view similar to FIG. 1 to show the installed location of a second inflatable/deflatable embodiment of the invention; and
FIG. 8 is a view similar to FIG. 2, for the inflated condition of the second embodiment.
DETAILED DESCRIPTION
The diagram of FIG. 1 provides body context for features of the principal veins to a patient's heart via the right atrium. An installed caval filter 10 of the invention is seen to comprise an inflated longitudinally fluted balloon at the distal end of an elongate multi-lumen stem 11. The filter will be understood to have been inserted, in deflated state, via one of the patient's femoral veins, here shown as the right femoral vein, and into the inferior vena cava at a region short of the renal veins and therefore proximal with respect to venous-return to the heart via the right atrium. The filter 10 is introduced into the body by way of conventional catheter-insertion procedures, which may rely upon an introducer and/or a guide wire. These procedures form no part of the invention and therefore need not be described, beyond noting that the stem 11 is flexible and has special provision for selective delivery of an inflating flow of pressure fluid to the balloon from an external source (not shown), or for extraction of pressure fluid from the balloon, in a deflation of the balloon, as in a procedure to remove the filter from the patient.
In FIGS. 2 and 3, the filter 10 and its stem 11 are shown to have a central lumen or passage 12 at the inner end of a radial strut 12', for piloted guidance along a guide wire 13, and stem 11 has two further lumens, both of which are closed, at least at the distal end 11' of stem 11. One of these lumens provides a passage 14 for the pressure fluid to inflate or deflate the balloon, and the other lumen provides at 15 for flow of a medicating fluid, such as a contrast medium or a thrombolizing agent; external supply to these respective lumens is suggested at arrows 14', 15' in FIG. 2. In FIG. 3, plural further arrows 16 at equal angular spacing align with radial apertures 17 in the cylindrical wall of stem 11, providing uniformly distributed introduction of such fluid from lumen 15 and into the venous-return flow at a location of proximal offset L 1 from filter 10; the offset L 1 may be in the range of 3 to 10 centimeters, and preferably 5 to 7 centimeters. In FIG. 3 the apertures 17 are shown all at the same position longitudinally of the stem 11, but it will be appreciated that a spiral or other longitudinal spacing of the apertures 17 so as not to weaken unduly the stem wall is to be preferred, the apertures 17 preferably extending fully around the stem 11.
The balloon 10 intentionally partially occludes the local vena-cava section, by inflating to establish plural flutings or radial fins 18, shown in the drawings to be in a plurality of six, at equal angular spacing. These radial fins may be developed helically, for example with a steady angle of helical advance over the effective length L 2 of the balloon, in which case the passages 14 and 15 may likewise be of helically advancing nature with respect to the central passage 12 and the openings 17 may similarly follow a helical path. In the form shown the radial fins extend in planes parallel to and including the central axis of the filter, which in the wire-guided case shown is the axis of guide passage 12. In FIG. 4, the inner wall of the vena cava is seen at 20, and the stem or core 11 is stabilized by the inflated six contact alignments of fins 18, for substantially the full longitudinal extend L 2 of the filter.
More particularly, the plural fins 18 of balloon 10 are integral with each other, and the balloon itself may be manufactured from a moulding mandrel 22 having generally the cross-section shown in FIG. 6, namely, a central core 23 and plural radial fins 24. The core 23 will be understood to have cylindrical longitudinal ends which project beyond the distal and proximal ends of fins 24, these cylindrical ends are designed to develop a glove-like fit of the moulded balloon over and to the cylindrical outer surface of stem 11. The balloon 10 may be made by dipping the entire mandrel 22 in liquid elastomeric material such as latex and by allowing the same to cure, prior to extracting the moulded balloon from the mandrel, as by delivering a blast of pressurized air to the crotch 25 between each pair of adjacent fins 24; for this purpose, FIG. 6 shows a central longitudinal passage 26 and a separate radial alignment 27 for delivery of pressurized air into each crotch 25. With one end of passage 26 closed, and the other end supplied with compressed air, cured balloon material of fins 18 will strip from the mould fins 24 and will be stretched radially outward, enough to establish a clearance for removal from the mould. Having been cured prior to stripping, the moulded balloon can be readily returned to uninflated condition, and cut at its tubular ends, for assembly to the distal end of stem 11, the short distal ends of the balloon being circumferentially sealed and bonded to the cylindrical shape of the stem, as suggested at 28, 29 in FIG. 2.
The presently preferred construction of balloon 10 is completed by individual non-stretch reinforcing elements 30 (see FIG. 4), which may be filaments of wire or of suitable plastic material, taut in each crotch 25 and retained by longitudinally spaced bonds, such as those which at 28, 29 establish the sealed relation of balloon 10 to the stem 11. The elements 30 might alternatively be formed integrally with the balloon material, rather than as separate elements, and might for example be formed simply as a thickening of the balloon material at the appropriate locations, the balloon when inflated thus being intrinsically fluted without need for the element 30.
It will be understood that internal communication for passage of inflation/deflation fluid into and from balloon 10 may be via internal connection of passage 14 to each of the inflatable-fin structural features of the balloon. In the construction of the stem 11 in the region of prospective balloon-10 assembly thereto, the large lumen 15, for use in injection of a thrombolytic agent or other material, is closed by locally plugging the same at short distal offset from the plural apertures 17 (i.e., within the longitudinal space L 1 ), such plugged location being designated schematically at P in FIG. 2. That being the case, in the region distally beyond the plug at P and proximally of the distal end closure at 11', one or more axially spaced sets of radial apertures in the span L 2 of prospective balloon assembly to stem 11 may be provided in the stem wall at precisely the angular spacings shown in FIG. 3 for the radial apertures 17; and a skewed drill alignment, such as that suggested by phantom lines 31 in FIG. 3 (performed within the longitudinal region of the L 2 span of balloon assembly) may communicate inflation/deflation flows to and from the manifolding volume of lumen 15, within the span L 2 . Once this drilled passage has been accomplished, a short plug of the outer open end of the drilled passage will close the same to external access, without interfering with passage 14 communication with lumen 15.
The balloon part of the filter assembly as thus described is shown in the drawings as having substantially squared proximal and distal ends. This, of course, need not be the case and it might be preferred for the ends of the balloon to taper or curve down to the stem 11.
In use, the filter assembly 10, 11 is installed via guide wire 13, with balloon 10 in fully deflated condition, wherein each of the radial fins 18 is fully collapsed and wrapped around stem 11. This wrapped condition is readily achieved by rotating the balloon and its fins in a single direction about the stem axis, while evacuating the balloon and progressively reducing its cylindrical circumference; the operation culminates in an umbrella-like wrap, depicted in FIG. 5. When sufficiently inserted to assume the desired position in the inferior vena cava, as shown in FIG. 1, inflation fluid, which may be a viscous liquid containing just enough of a contrast component for x-ray visibility, is injected at 14', causing fins 18 to inflate and assume their radially outward expansion into light equally spaced multiple self-stabilizing contacts with the inner surface of the vena-cava wall 20. Thus erected, balloon 10 occludes a significant fraction of the sectional area of the vena cava, and substitutes therefor a plurality of passages A, B, C, D, E, F of substantially triangular section for thereafter limiting passage of any blood clot to at least a small enough size as not to present a problem to the pulmonary artery or to the hear, i.e., to a size much reduced from a 7.5-mm clot size which otherwise might be lethal. Injection of a thrombolytic agent at 15' may commence at once for circumferentially diffused delivery to the situs of any thrombi trapped by one or more of the passages A to F, thus lysing such thrombi.
Having used the described filter to the extend deemed necessary by the physician in charge, the described filter is removed by first deflating the same, preferably while rotating stem 11 to enable an umbrella-like wrap of deflated fins 18 to develop as seen in FIG. 5.
In FIGS. 7 and 8 parts that correspond to what has been described for FIGS. 1 to 6 are shown with the same numbers, but indexed in a 100-series. The embodiment of FIG. 7 is in virtually all its aspects the same as what has been described in connection with FIGS. 1 to 6, the differences being that in FIG. 7 (i) installation of the inflatable balloon 110 and its stem 111 is via the right jugular vein, through the superior vena cava, and past the right atrium and renal veins, for lodgement in the inferior vena cava as shown, and (ii) the distal end 111' of stem 111 projects distally beyond balloon 110, so that injection of a thrombolytic agent via apertures 117 may be sufficiently proximal with respect to venous flow to and through filter 110, and therefore proximal to any entrapped thrombi for ensuring optimal lysis of thrombus, to assure the previously described proximal offset L 1 from the filter.
More particularly, for the jugular-vein insertable device of FIGS. 7 and 8, the stem 111 section may be as described for stem 11 in connection with FIG. 3, but the use of this section is better dedicated to a reversal of functions for the externally served lumens 14, 15. Thus, for the case of FIGS. 7 and 8, it is preferred to utilize the large lumen 15 up to the location Q in FIG. 8, for inflation/deflation operation of balloon 110, lumen 15 being understood to have been locally blocked at Q, and of course both lumens 14, 15 being blocked at R, i.e., at the distal end of stem 111, i.e., distally of the location of the radial apertures 117. And in the region of stem 111 between locations Q and R, a skewed drilling as on the alignment 31 of FIG. 3 will establish exclusive communication between passage 14 and the relatively large volume of lumen 15; there being a small local external plug of the drilled alignment 31, for assurance of thrombolytic-agent delivery to lumen 15 and its circumferentially distributed apertures 117, at a vena-cava location that is at sufficiently proximal offset L 1 from the zone of inflated filter occlusion of the vena cava.
The invention will be seen to achieve all stated objects with relatively simple and easily operated structure which cannot become rooted in tissue growth within the vena cava. The structure may therefore remain within a patient for as long as his physician deems necessary, with facile, unharmful withdraw when desired, namely, long after the hitherto necessary time of 48 hours.
In the foregoing, there have been described inflatable/deflatable embodiments of the present invention wherein pressure fluid is delivered to a balloon for inflation of the device and is extracted therefrom for deflation. For the avoidance of doubt, it is to be understood that the pressure fluid could possibly be at atmospheric pressure, the balloon being formed with resilient structures such as will enable it to be deflated by suction and to be inflated by removal of the suction and exposure of the balloon interior to atmospheric pressure. By the same token, the inflation and deflation pressures could both be negative pressures relative to atmospheric pressure. Reference to inflation and deflation in the foregoing and in the appended claims should be construed accordingly.
Having thus described the invention by reference to exemplary embodiments it is to be well understood that modifications and variations are possible without departure from the spirit and scope of the invention as set forth in the appended claims. For example, the fluted balloon configuration of the described embodiments is not essential and any geometrical or other balloon shape which partly occludes the cross-sectional area of the vena cava could be utilized. In a simple form, the balloon could for example have a triangular, rectangular or other trapezoidal form. | A vena-cava filter features an inflatable balloon at or near the distal end of an elongate flexible multiple-lumen core or stem. The balloon is suitably configured in a preferred construction at or near the distal end of an elongate flexible multiple-lumen core. The balloon is suitably configured in a preferred embodiment for femoral-vein insertional installation; and in another embodiment the balloon is suitably configured for jugular-vein insertional installation. In both embodiments, the balloon is deflated prior to insertion; it is inflated to become a filter when properly positioned in the vein, and finally it is deflated for removal purposes. Installation may proceed pursuant to guide-wire techniques commonly used for catheter installation. Each of the indicated two embodiments is described for the case of additionally providing for injection of a tracer or a thrombolytic agent at a location in the vein at proximal (i.e., upstream) offset from the region of filter action. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to means for self-locking nuts on threaded bolts of saddle clamp assemblies and the like.
2. Description of the Prior Art
There are various known types of self-locking threaded assemblies, but these have certain disadvantages. Some of these arrangements rely on hardened spring steel, special lock-nuts, or special bolts, all of which are relatively expensive. Further, where the component parts are subjected to heat, it is undesirable to use hardened steel washers and the like because they loose their temper or fracture. Another disadvantage of prior art arrangements is that the nuts will exert considerable friction when rotated on the threads, and this requires tools for assembling or disassembling.
SUMMARY OF THE INVENTION
According to a typical embodiment of the invention, there is a muffler saddle clamp and a U-bolt having arms which extend through openings provided therefore in the flat, closed, end part or base of the clamp. The flat end part or base of the clamp is deformed to provide a shoulder extending transversely of said end part or base, there being a shoulder adjacent each of the openings through which the threaded ends of the U-bolt extend. A standard finished hex-nut is disposed on each of the threaded ends of the U-bolt extend. A standard finished hex-nut is disposed on each of the threaded ends of the U-bolt and the respective shoulders are spaced from the adjacent threaded end of the U-bolt the distance of the thickness of the nut from the inside to the thinnest parts or flat sides of the nut. In tightening the assembly to an exhaust pipe, the nuts on the U-bolt are tightened and the corners of the nut will initially slip past the shoulder and allow the nut to be seated on the adjacent surface of the end part of the clamp with one of the outer flat sides of the nut in abuttment against the adjacent shoulder.
OBJECTS AND ADVANTAGES OF THE INVENTION
It is an object of the present invention to provide a muffler saddle clamp assembly having self-locking means for locking the nuts on the U-bolt of the device.
It is another object of the invention to provide an assembly of this character wherein the base of the saddle clamp has openings for the threaded ends of the U-bolt and at least one shoulder adjacent each opening against which one flat side of a hex-nut engages when the nut is forced against said base.
It is still another object of the invention to provide a device of this character wherein standard finished hex-nuts are used for the respective ends of the U-bolt.
It is a further object of the invention to provide a device of this character wherein the nuts will turn freely on the threaded ends of the U-bolt until it contacts the saddle clamp base.
It is a still further object of the invention to provide a device of this character wherein the base of the saddle clamp is deformed with a part adjacent the shoulder which is inclined toward said shoulder.
It is another object of the invention to provide a device of this character that is simple in construction and operation.
It is still another object of the invention to provide a device of this character that is relatively inexpensive to manufacture.
The characteristics and advantages of the invention are further sufficiently referred to in connection with the following detailed description of the accompanying drawings which represent certain embodiments. After considering these examples, skilled persons will understand that many variations may be made without departing from the principles disclosed and I contemplate the employment of any structures, arrangements or modes of operation that are properly within the scope of the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the drawings, which are for illustrative purposes only:
FIG. 1 is a side elevational view of a clamp assembly embodying the present invention, a portion being broken away;
FIG. 2 is an exploded, perspective view thereof;
FIG. 3 is a fragmentary, enlarged, sectional view showing the threaded portion of one arm of the U-bolt and the deformed end of the base of the saddle clamp, the nut being partly threaded onto said threaded arm;
FIG. 4 is a similar view showing the nut seated on said deformed part of the saddle clamp base;
FIG. 5 is a view taken on line 5--5 of FIG. 4;
FIG. 6 is a fragmentary, sectional view of an alternative arrangement; and
FIG. 7 is a fragmentary, sectional view of another alternative arrangement.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 to 5 inclusive, there is shown one embodiment of the invention. In this embodiment, the muffler saddle clamp assembly includes a saddle clamp, indicated generally at 10 and a U-bolt, indicated generally at 12.
The saddle clamp 10 is formed from mild steel plate and is generally U-shaped in cross-section. It comprises arms 14 which are substantially parallel to each other and spaced apart with a base 16 connecting the arms together. Arms 14 are formed with arcuate notches 18 from their free ends, said notches being of the same size.
The base 16 of the saddle clamp has openings or holes 20 adjacent the ends thereof for reception of threaded free end portions 21 of the U-bolt 12. Each end of the base has a deformed portion 22 best shown in FIGS. 1, 2 and 3. Each deformed portion includes one of the openings or holes 20 and is inclined from adjacent free end of the base 16 inwardly and terminates in a transverse shoulder 24.
As best shown in FIG. 1, the saddle clamp arms receive a semi-circular part of a pipe 26 and the curved, closed portion 28 of the U-bolt extends about the other semicircular portion of the pipe 26 with the threaded free end portions 21 of the arms 32 extending through the openings 20 of the base of the clamp 10. A hex-nut, indicated generally at 34 is threaded onto the threaded end portions 21 of the U-bolt and said nuts are turned down until they engage the shoulder 24. Since the outer end of the deformed portion 22 is slightly spaced upwardly of the outer surface of the base, as best shown in FIG. 3, rotation of the nut with a wrench will first cause points 34a of the exterior of the nut to first engage the free outer edge of the shoulder, as best shown in FIGS. 1 and 4, and it is to be noted that up to this point, the nut turns freely on the threaded end of the "U" bolt. Further turning of the nut with the wrench, will cause the nut to be forced against the shoulder and the outer end of the deformed part 22, and tightening of the nut will force the inclined part 22 into flattened, parallel relationship to the plane of the outer surface of the base 16, as best shown in FIG. 4. When thus tightened, one of the flat sides 34b of the nut engages the shoulder 24. Thus, the nuts are securely locked in the tightened positions.
In use, a free end portion of an exhaust pipe 36 is inserted into one end of the pipe 26 and a free end portion of a muffler pipe is also inserted into the opposite end of pipe 26. The nuts 34 are then tightened to secure the pipe together in the usual well known manner.
Referring to FIG. 6, there is shown an alternative arrangement, wherein the base 16 of the saddle clamp is deformed as at 38, the part 38 is off-set from the main portion of the base 16 and in a plane parallel thereto.
The sequence of operation in this embodiment is substantially the same as that described in connection with the embodiment of FIGS. 1 through 5, except that, as the nut 34 is tightened its corners 34a will engage the shoulder 24a. As the nut is further tightened, it will seat flat in the part 38 with one of the sides 34b of the nut engaging the shoulder 24a.
In FIG. 7 there is disclosed another alternative arrangement wherein the ends of the base 16 of the clamp are off-set to provide parts 40 which are in planes off-set from the main portion of the base 16 and in a plane parallel thereto. In this arrangement there is an outer shoulder 42 similar to the shoulder 24a but oppositely arranged. In this arrangement, as the nut 34 is tightened, the external points 34a of the nut 34 engage the shoulders 24a and 42. As the nut is further tightened, it will seat flatly on the part 40 with opposite flat sides in engagement with said shoulders.
In these various embodiments, where the nut is fully tightened, it is held against unscrewing by the engagement of the flat sides 34b of the nuts with the shoulders.
While a hex-nut is shown and described it is to be understood that nuts having a different number of flat exterior sides may be used.
The invention and its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts of the invention without departing from the spirit or scope thereof or sacrificing its material advantages, the arrangement hereinbefore described being merely by way of example, and I do not wish to be restricted to the specific form shown or uses mentioned except as defined in the accompanying claims. | A muffler saddle clamp having a nut-locking action by using the flat of a standard finished hex-nut against a stop formed on the base of saddle clamps. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an information signal recording apparatus, an information signal recording method, an information signal reproducing apparatus, and an information signal reproducing method.
2. Description of the Related Art
Recording and reproducing apparatuses corresponding to the digital video (DV) format for recording and reproducing a digital video signal, for example a camcorder (which is a general product name derived from camera and recorder), have been widespread. The following Patent Document 1 describes an apparatus that records and reproduces, by using a tape and a rotating head unit that are the same as those of a DV format camcorder, high definition (HD) data that have been compressed in accordance with MP@H-14 prescribed in the Moving Picture Experts Group Phase 2 (MPEG2) system. The contents described in Patent Document 1 are referred to as the HDV2 standard.
[Patent Document 1] Japanese Patent Laid-Open Publication No. 2002-314941
The patent document 1 describes a technology for forming search picture data with I pictures, causing intervals of intraframes used as search data constant, and decreasing the data amount of high speed search pictures. The MPEG2 system uses intra-coded pictures (I pictures), predictive-coded pictures (P pictures), and bidirectionally predictive-coded pictures (B pictures) in accordance with different encoding systems.
An I picture is a picture of which, when it is encoded, only information thereof is used. Thus, an I picture can be decoded without need to use other information. When a search operation is performed, since the path of a rotating head does not match a track formed on a tape, only a fragment of data is reproduced. Thus, it is necessary to form search pictures with I pictures.
A P picture is a picture that uses an I picture or a P picture that has been decoded chronologically before the current P picture as a predictive picture (a reference picture for obtaining the difference between two pictures). The difference between the current P picture and a predictive picture that has been motion-compensated is encoded. Alternatively, the current P picture is encoded. One of the two methods is selected in the unit of a macro block so that a higher effect can be obtained.
A B picture is a picture that uses three types of pictures that are an I picture or a P picture that has been decoded chronologically before the current B picture, an I picture or a P picture that has been decoded chronologically after the current B picture, and an interpolated picture formed with the foregoing two types of pictures, as a predictive picture (a reference picture for obtaining the difference between two pictures). Based on the three types of reference pictures that have been motion-compensated the differences are encoded. Alternatively, the three types of pictures are intra-encoded. One of these methods is selected in the unit of a macro block so that a higher effect can be obtained.
Thus, there are four types of macro blocks that are an intra-frame coded macro block of which a current macro block is encoded in a frame, a forward inter-frame macro block of which a future macro block is predicted with a past macro block, a backward inter-frame predictive macro block of which a past macro block is predicted with a future macro block, and a bidirectional macro block of which a current macro block is predicted from both the forward and backward directions. A P picture contains an intra-frame coded macro block and a forward inter-frame predictive macro block. A B picture contains all the four types of macro blocks.
In Patent Document 1, to decrease the data amount of search pictures, DC components are extracted from discrete cosine transform (DCT) blocks of a luminance signal and color difference signals and the number of bits of each of the extracted DC components is decreased from the original 8 bits to 6 bits (for each of DC components of the luminance signal) and 5 bits (for each of DC components of the color difference signals).
Since the number of bits that are decreased is large, from 8 bits to 5 bits, the possibility that small color difference data is truncated to 0 is high. Video data photographed by for example a video camera contains many portions that have low signal levels. Depending on a picture pattern, most of a picture on a screen may be truncated to 0. As a result, search pictures may be formed as colorless pictures. Search pictures can be coarse pictures. However, if search pictures are colorless, the user may feel uncomfortable or mistake them for a trouble of the apparatus.
OBJECTS AND SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide an information signal recording apparatus, an information signal recording method, an information signal reproducing apparatus, and an information signal reproducing method that prevent search pictures of which the number of bits of color data is decreased for compressing the data amount of the search pictures from becoming colorless.
To solve the foregoing problems, a first aspect of the present invention is an information signal recording apparatus for compression-encoding video data and recording the compression-encoded video data onto a recording medium, the information signal recording apparatus comprising:
a search picture generating block configured to decrease the bit length of a component of a luminance signal and the bit length of a component of a color signal of an intra-coded data of the compression-encoded video data so as to generate search picture data; a color signal compensating block configured to compensate the component of the color signal processed by the search picture generating block so as to increase the level of the component of the color signal; and a recording block configured to dispersedly record the search picture data generated by the search picture generating block onto the recording block.
A second aspect of the present invention is an information signal reproducing apparatus for reproducing data from a recording medium on which compression-encoded video data has been recorded and search picture data and search data information have been dispersedly recorded, the search picture data having been generated by decreasing the bit length of a component of a luminance signal and the bit length of a component of a color signal of intra-coded data of the compression-encoded video data, the search picture data having been generated by compensating the component of the color signal so as to increase the level of the component of the color component, the search data information representing the amount of increase of the level increased by a color signal compensating block, the information signal reproducing apparatus comprising:
a reproducing block configured to reproduce the compression-encoded video data from the recording medium when a normal reproducing operation is performed and reproduce the search data information and the search picture data from the recording medium when a search reproducing operation is performed; a decompression-decoding block configured to decode a reproduction picture from the reproduced compression-encoded picture data; and a search picture decoding block configured to decode the search picture from the search picture data with the reproduced search data information.
A third aspect of the present invention is an information signal recording method for compression-encoding video data and recording the compression-encoded video data onto a recording medium, the information signal recording method comprising the steps of:
decreasing the bit length of a component of a luminance signal and the bit length of a component of a color signal of an intra-coded data of the compression-encoded video data so as to generate search picture data; compensating the component of the color signal processed at the search picture generating step so as to increase the level of the component of the color signal; and dispersedly recording the search picture data generated at the search picture generating step onto the recording block.
A fourth aspect of the present invention is an information signal reproducing method for reproducing data from a recording medium on which compression-encoded video data has been recorded and search picture data and search data information have been dispersedly recorded, the search picture data having been generated by decreasing the bit length of a component of a luminance signal and the bit length of a component of a color signal of intra-coded data of the compression-encoded video data, the search picture data having been generated by compensating the component of the color signal so as to increase the level of the component of the color component, the search data information representing the amount of increase of the level increased by a color signal compensating block, the information signal reproducing method comprising the steps of:
reproducing the compression-encoded video data from the recording medium when a normal reproducing operation is performed and reproducing the search data information and the search picture data from the recording medium when a search reproducing operation is performed; decoding a reproduction picture from the reproduced compression-encoded picture data; and decoding the search picture from the search picture data with the reproduced search data information.
According to the present invention, before search data is generated, color data is processed. As a result, the problem that search pictures become colorless can be solved.
These and other objects, features and advantages of the present invention will become more apparent in light of the following detailed description of a best mode embodiment thereof, as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will become more fully understood from the following detailed description, taken in conjunction with the accompanying drawing, wherein similar reference numerals denote similar elements, in which:
FIG. 1 is a block diagram showing a recording system and a reproducing system of a digital VCR according to the present invention.
FIG. 2 is a schematic diagram describing the structure of the time base of search picture data.
FIG. 3 is a schematic diagram describing search picture data.
FIG. 4A , FIG. 4B , and FIG. 4C are schematic diagrams describing the arrangement of search picture data on a tape at eight-times high speed.
FIG. 5 is a schematic diagram showing an example of the data structure of a search sync block.
FIG. 6 is a schematic diagram describing packet data of a search sync block.
FIG. 7 is a block diagram showing an example of the structure of a search picture generating block.
FIG. 8 is a schematic diagram showing a distribution of levels of a color signal for one frame.
FIG. 9 is a block diagram showing an example of the structure of a color signal level compensating block.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Next, with reference to the accompanying drawings, an embodiment of the present invention will be described. FIG. 1 shows an outlined structure of a section that mainly processes a video signal of a digital VCR according to the present invention. An input video signal is supplied to an A/D converter 1 . The A/D converter 1 converts the input video signal into a digital video signal. The digital video signal is supplied to a compressing block 2 . The compressing block 2 compresses the digital video signal in accordance with MP@H-14 of the MPEG2 system. The compressed video data (packetized elementary stream: PES) is output from the compressing block 2 to a data multiplexing block 3 .
The data multiplexing block 3 multiplexes the compressed video data, compressed audio data, system data, search picture data, and so forth. Output data of the data multiplexing block 3 is supplied to an error correction code encoder 4 . The error correction code encoder 4 encodes the output data of the data multiplexing block 3 with an error correction code. The encoded data is supplied to a rotating head 6 through a recording amplifier 5 . Inclined tracks are successively formed on a tape wound around the periphery of the rotating drum having a pair of rotating heads disposed thereon so that they are opposite to each other with an angle of for example 180°.
The video data that has been compressed by the compressing block 2 are supplied to a search picture generating block 7 . The search picture generating block 7 generates search picture data with the compressed video data. The generated search picture data is supplied to the data multiplexing block 3 . The data multiplexing block 3 multiplexes the search picture data with record data.
Reproduction data that is reproduced from the tape by the rotating head 6 are supplied to an error correction code decoder 12 through a reproducing amplifier 11 . The error correction code decoder 12 corrects an error of the reproduction data. In addition, the error correction code decoder 12 detects a synchronous signal, an ID, and so forth. The reproduction data that is output from the error correction code decoder 12 are supplied to a data separating block 13 .
The data separating block 13 separates the reproduction data into compressed video data, compressed audio data, reproduction search picture data, system data, and so forth from the reproduction data. The compressed video data separated by the data separating block 13 is supplied to a decompressing block 14 . The decompressing block 14 decompresses the compressed video data and obtains base band reproduction video data. The reproduction video data is supplied to a terminal a of a switch SW. When the normal reproduction operation is performed, the reproduction video data is supplied to a D/A converter 15 through the switch SW. The D/A converter 15 obtains an analog output video signal.
The reproduction search picture data is supplied to a search picture decoding block 16 through the error correction code decoder 12 . The search data information is supplied from the data separating block 13 to the search picture decoding block 16 . The reproduction search picture data decoded by the search picture decoding block 16 are supplied to a terminal b of the switch SW. When the search operation is performed, the search picture signal, which is an analog video signal, converted by the D/A converter 15 is obtained as an output video signal through the terminal b of the switch SW.
FIG. 2 shows a compressing process performed by the compressing block 2 for video data. The compressing block 2 compresses frames in the unit of one GOP (group of pictures) (GOP 1 , GOP 2 , and so forth). One GOP is composed of 15 frames.
FIG. 3 describes the structure of the time base of base data of search picture data of the 1080i/60 television system. The search picture data comprises base data and helper data. One frame is divided into for example 68 macro blocks×90 macro blocks. Each macro block comprises four DCT blocks of a luminance signal and two DCT blocks of color difference signals. One DCT block has a size of (8 pixels×8 pixels). These six DCT blocks are arranged at the same spatial position.
The search picture generating block 7 selects a DC component of for example Y 0 from Y 0 , Y 1 , Y 2 , and Y 3 having 6 bits each as coefficient data obtained from four DCT blocks of the luminance signal of the same macro block. A DC component of 6 bits is generated in such a manner that the low order 2 bits of 8 bits are cut off. DC components (Cb and Cr) of 5 bits each as coefficient data obtained from the color difference signals of the same macro block are generated in such a manner that the low order 3 bits of 8 bits are cut off.
When picture data of an I picture contained in one GOP is processed in such a manner, search picture data corresponding to each GOP can be generated. In the cut-off (truncating) process for the bit length of the color difference signals, since the low order 3 bits of 8 bits are cut off, colors of a light color picture disappear. According to the present invention, such a problem is solved by the following process.
The tape traveling speed in the search operation is higher than that in the recording operation. Thus, data is fragmentally reproduced from a plurality of tracks by the reproducing heads. Thus, when the search operation is performed at a predetermined higher speed than the normal reproduction operation, it is desired that reproduction search picture data be recorded at positions from which they are reproduced.
FIG. 4A shows a search operation at eight-times high speed. In FIG. 4A , vertical stripes represent tracks formed on the tape. An inclined arrow mark represents a path that the rotating head traces in the search operation. When the search operation is performed, for example only one of the two rotating heads is used. When the search operation is performed at eight-times high speed, the rotating head traces eight tracks of the tape at a time. The rotating head traces the tape at intervals of 16 tracks. The speed of the search operation is not limited to eight-times high speed. Alternatively, the speed of the search operation may be for example 24-times high speed. In addition, the user may be able to set one of a plurality of high speeds.
One error-correction code (ECC) unit comprises 16 tracks. An error is corrected every ECC unit. In the track pattern shown in FIG. 4A , No. 0 to No. 8 each represent one ECC unit. When the search operation is performed at eight-times high speed, the rotating head traces the tape at intervals of 16 tracks. Thus, when the phase that the rotating head traces is controlled, the rotating head traces a predetermined path in each ECC unit. When search picture data is recorded on the path, the search picture data can be securely reproduced.
Since main picture data cannot be recorded in a portion for search picture data, the data amount of the search picture data is small. When search picture data cannot be reproduced, it can be interpolated with main picture data adjacent thereto. Alternatively, an extra recording area may be formed in the recording format of the tape. Search picture data may be recorded in the extra recording area.
FIG. 4B shows a process for base data of the foregoing search picture data. The base data comprises a total of 16 bits of a DC component Y 0 (6 bits) as a DCT block of the luminance signal and DC components Cb and Cr (5 bits each) as DCT blocks of the color difference signals of one macro block. Record data is recorded in the unit of a sync block (hereinafter abbreviated to as SB).
The number of macro blocks that are contained in one sync block is (720/16=45). When the search operation is performed, 34 sync blocks can be obtained every ECC block. The base data is recorded at predetermined positions of four successive ECC units. Thus, when the rotating head traces the tape four times, base data of (45 macro blocks×34 sync blocks×4=6120 macro blocks) can be obtained.
FIG. 4C describes helper data of search picture data. DC components Y 1 , Y 2 , and Y 3 of 6 bits each (a total of 18 bits) as the remaining three DCT blocks other than the DCT block used as the base data is helper data. The number of macro blocks of the helper data contained in one sync block is (720/18=40). When the search operation is performed, 34 sync blocks can be obtained every ECC unit. The base data is recorded at predetermined positions of five successive ECC units. When the rotating head traces the tape five times, helper data of 45 macro blocks×34 sync blocks×5=6800 macro blocks can be obtained.
The search picture decoding block 16 of the reproduction side decodes search picture data with both the base data and helper data. Even if the helper data is lost, when the base data can be reproduced, a search picture having a low resolution can be obtained.
FIG. 5 shows an example of the data structure of a search sync block into which search picture data is inserted. In FIG. 5 , a synchronous signal of 2 bytes, an ID of 3 bytes (the synchronous signal and the ID are placed at the beginning of a sync block), and an inner code parity of 10 bytes of an error correction code (the inner code parity is placed at the end of the sync block) are omitted. One sync block has a length of 111 bytes. Thus, FIG. 5 shows only 96 bytes of 111 bytes of one sync block without data of 15 bytes that are omitted.
An sync block header of 1 byte (8 bits) is placed at the beginning of 95 bytes. The sync block header is data that represent the contents of data of the sync block. The sync block header is followed by a search sync block header of 40 bits. The search sync block header is followed by search picture data of 720 bits. A sync block for regular video data does not have the search sync block header. Thus, the sync block can record main data of 760 bits.
As described above, search picture data has base data and helper data. One sync block can contain base data of 45 macro blocks. In FIG. 5 , MB 0 to MB 44 represent macro blocks of base data. Each macro block contains a DC component Y 0 (6 bits) of the luminance signal and DC components Cb and Cr (5 bits, each) of the color difference signals. On the other hand, one sync block SB can contain helper data of 40 macro blocks from MB 0 to MB 39 . Each macro block contains DC components Y 1 , Y 2 , and Y 3 (6 bits, each) other than a DC component Y 0 of the luminance signal.
The search sync block header contains an address (horizontal x and vertical y) that represents the position of the sync block data in one picture of the search picture data, a packet header, packet data, and so forth. The packet header (5 bits) is information that represents the contents of the packet data (16 bits).
FIG. 6 shows contents of packet data corresponding to the values (0 to 31) of the packet header. When all 5 bits of the packet header are 0's and L/H is L, the packet data is a search header. In addition, the contents of the sub code are recorded as packet data. Values 16 to 31 of the packet data are currently reserved (undefined). In addition, in FIG. 5 , Rsv represents undefined.
As will be described later, according to the embodiment of the present invention, a compensating process is performed for the color difference signals of search picture data (main data). Thus, when the reproduction processing side is informed of the contents of the compensating process, undefined packet data is used.
FIG. 7 shows an example of the structure of the search picture generating block 7 . An I picture decoder 71 extracts one I picture from for example one GOP of compressed data of the compressing block 2 , decodes the extracted I picture, and generates one picture. However, as described above, since a search picture comprises only DC components, the I picture decoder 71 performs a process for extracting DC components from the luminance signal and the color difference components of a macro block of an I picture. Alternatively, the I picture decoder 71 may decode a base band picture, compensates a color signal, and then encode the compensated signal.
The color signal of the picture data that is output from the I picture decoder 71 is supplied to a color signal level compensating block 72 . The color signal level compensating block 72 compensates two types of color difference data of the decoded picture and supplies the compensated color difference data to a search data generating block 73 . The search data generating block 73 generates base data and helper data of search picture data in the foregoing method that has been prescribed in the standard.
The color signal level compensating block 72 prevents low level pixel data from becoming 0 and a search picture from becoming colorless when the bit length of color difference data is decreased. In other words, part or all the color signal of one frame is compensated so that the signal level increases.
When the low order 3 bits of the color signal are cut off and thereby converted into data of 5 bits, as shown in FIG. 8 , a portion (hatched portion) having a level whose absolute value is smaller than b1000 (dotted line) is truncated to 0. When the original level is larger than b1000, colors are not lost. Otherwise, the color signal is truncated to 0 and becomes colorless. The real color signal data is 2's complement with a sign. However, for simplicity, in the following description, it is assumed that the process for increasing the value of data and the level is performed for data represented with an absolute value (7 bits) excluding MSB (sign bit).
FIG. 9 shows an example of the structure of the color signal level compensating block 72 . In FIG. 9 , reference numeral 21 represents a level detecting block that detects the level of the color signal received from the I picture decoder 71 (namely, the levels of DC components separated from DCT blocks of the color difference signals of each macro block). In the structure shown in FIG. 9 , two level detecting blocks are disposed for the two color difference signals. Of course, one level detecting block 21 may be disposed. In this case, the level detecting block 21 timesharingly performs the level detecting process for the two color difference signals.
The level detecting block 21 detects the level of the color signal. The detected level is supplied to a comparator 22 and an accumulating circuit 23 . An input color signal is temporarily stored in a temporary storing block 25 . On the output side of the temporary storing block 25 , a level increasing circuit 26 is disposed. The level increasing circuit 26 obtains a color signal having an increased level. The amount of the increased level by the level increasing circuit 26 is controlled in accordance with comparison information obtained by comparators 22 and 24 . Output data of the level increasing circuit 26 is supplied to a search data generator 73 that generates search data. The search data generating block 73 performs a cut-off process for the low order 3 bits of the color signal data so as to convert the color signal data from 8 bits into 5 bits.
An upper limit value A and a lower limit value B are input to the comparator 22 . A constant value is supplied to the comparator 24 . The comparator 24 compares the output of the accumulating circuit 23 with the constant value. The color signal level compensating block 72 compensates the color signal level in accordance with one of the following methods so that the level of the color signal increases.
In a first compensating method, only data that is smaller than the threshold value b1000 is replaced with b1000. The upper limit value A that is input to the comparator 22 is b1000. When the detected level X of the comparator 22 is smaller than b1000 (namely, X<A (=b1000)), the level increasing circuit 26 replaces the level of the color signal having the relation of X<A with b1000 in accordance with the comparison information. The level increasing process prevents the level of the color signal data from being truncated to 0. In the first compensating method, the lower limit value B, the accumulating circuit 23 , the comparator 24 , and the temporary storing block 25 are not used.
In a second compensating method, only data whose detected level is smaller than the threshold value A (=b1000) and larger than the threshold value B is replaced with b1000. The comparator 22 compares not only the upper limit value A, but the lower limit value B with the detected level X. The level increasing circuit 26 replaces the level of the color signal having the relation of B<X<A with b1000 in accordance with the comparison information. It is preferred that the upper limit value A be fixed to b1000 and the lower limit value B be able to be set by for example an EEPROM. In this case, the lower limit value B can be set to a suitable value in accordance with for example an evaluated result of a picture pattern. In the second compensating method, the accumulating circuit 23 , the comparator 24 , and the temporary storing block 25 are not used.
In a third compensating method, a constant value for example b111 is added to all color signal data so as to increase the level of the color signal. In the third compensating method, the level increasing circuit 26 uniformly increases the level of the input color signal without the processes of the level detecting block 21 and the temporary storing block 25 . In addition, the processes of the comparator 22 and the comparator 24 are not required. The constant value b111 is only an example. The constant value is not limited to b111.
In a fourth compensating method, a constant value for example b111 is added to data having a level smaller than a threshold value for example b100. The comparator 22 compares the level X detected by the level detecting block 21 with the upper limit value A for example b1000. The level increasing circuit 26 performs a process for adding a constant value to only data having the relation of X<A. The threshold value b111 is just an example. The threshold value is not limited to b111. In the fourth compensating method, the level detecting block 21 , the comparator 22 , the accumulating circuit 23 , the comparator 24 , and the temporary storing block 25 are not used.
In a fifth compensating method, the minimum level Xmin of the color signal in a predetermined range is detected. Only when the minimum detected level is smaller than a threshold value A for example b1000 (Xmin.<A), the difference (A−Xmin.) between the threshold value A and the minimum detection level is added to all the color signal in the predetermined range. The predetermined range is for example one frame.
To detect the minimum level Xmin. of one frame, the comparator 22 successively compares the levels of the two color signals of one frame that are successively input, selects data having a smaller level in accordance with the comparison result, and compares the minimum level of the data that has been selected with the level of the next color signal. After the color signals have been compared for one frame period, the minimum level Xmin. for one frame is obtained.
After the minimum level Xmin. for one frame has been obtained, the comparator 22 compares the minimum level Xmin. with the threshold value A (=b1000). When the minimum level Xmin. is smaller than the threshold value A, the difference (A−Xmin.) between the threshold value A and the minimum level Xmin. is obtained and information of the difference is supplied to the level increasing circuit 26 . The level increasing circuit 26 adds the difference value to all the color signal in one frame stored in the temporary storing block 25 until the level increasing circuit 26 can detect the minimum level. This process compensates all the color signal data for one frame so that the color signal data has a level equal to or larger than A. In the fifth compensating method, the accumulating circuit 23 and the comparator 24 are not used.
In a sixth compensating method, an average level Xavr. of the color signal in a predetermined range for example one frame is detected. Only when the detected average level Xavr. is smaller than a threshold value, a value is added to all color signal data in the predetermined range so as to increase the level of the color signal. The accumulating circuit 23 accumulates the values of the color signal for one frame. The accumulated value corresponds to the average level Xavr. The accumulated value may be divided by the number of pixels so as to obtain the average level.
The average level Xavr. obtained by the accumulating circuit 23 is supplied to the comparator 24 . The comparator 24 compares the average level Xavr. with a constant value (threshold value). The constant value is for example a value close to b1000. When the detected result represents that the average level Xavr. is smaller than the constant value, comparison information is supplied to the level increasing circuit 26 . The level increasing circuit 26 adds the constant value to all the color signal for one frame stored in the temporary storing block 25 until the level increasing circuit 26 can detect the average level. It is preferred that at least one of the constant value of the comparator 24 and the constant value added by the level increasing circuit 26 be variable. In the sixth compensating method, the comparator 22 is not used.
In the foregoing first to sixth compensating methods, when the recording operation is performed, the level of the color signal is increased. When the search reproducing operation is performed, since a search picture can be a coarse picture, it is not necessary to reversely compensate the level of the color signal. Simply, low order 3 bits (all 0's as an absolute value) need to be added to 5 bits. However, when a search picture needs to have the quality of a record picture (main picture), the reproduction side needs to perform a process for reversely compensating the level of the color signal.
Information that causes the reproduction side to decrease the level of the color signal is recorded onto the tape. For example, as described in FIG. 5 , information as undefined packet data of a sync block of a search picture is recorded onto the tape. When a plurality of compensating methods are used, information that represents the compensating methods and information that represents the amount of increase of the level of the color signal are recorded as packet data. A packet header that represents that information about compensation of the color signal is newly defined.
In the structure on the reproduction side shown in FIG. 1 , the data separating block 13 separates data into a packet header and packet data. The data separating block 13 supplies search data information necessary for decoding the level of the color signal to the search picture decoding block 16 . With the search data information, the color signal of 8 bits that is as close to the original value as possible can be decoded.
Although the present invention has been shown and described with respect to a best mode embodiment thereof, it should be understood by those skilled in the art that the foregoing and various other changes, omissions, and additions in the form and detail thereof may be made therein without departing from the spirit and scope of the present invention. According to the present invention, for example, the recording process, reproducing process, search picture data generating and restoring process, and so forth may be performed by either or both hardware and software. In addition, the present invention can be applied to the case that a recording medium such as an optical tape or an optical disc is used instead of a magnetic tape. | An information signal recording apparatus for compression-encoding video data comprising a search picture generating block AND a color signal compensating block. The search picture generating block decreases the bit length of a component of a luminance signal and the bit length of a component of a color signal of an intra-coded data of the compression-encoded video data to generate search picture data, and the color signal level compensating block compensates the signal level of part or all the color signal for one frame so that the signal level increases. | 7 |
FIELD OF THE INVENTION
The present invention relates to catalyst for the liquid phase oxydehydration of glycerol to acrylic acid with hydrogen peroxide as oxidant for the production of acrylic acid and process for the preparation of the catalyst. Particularly, the present invention relates to a process for the single step conversion of glycerol to acrylic acid over nanocrystalline Cu supported α-MnO 2 catalyst. More particularly, the present invention relates to a process for the liquid phase conversion of glycerol to acrylic acid by using a single Cu—Mn catalyst with hydrogen peroxide as oxidant.
BACKGROUND OF THE INVENTION
As the dependency on fossil fuel are increasing constantly, new formula is modified from the Klaus model and thus assumes a continuous compound rate and computes fossil fuel reserve depletion times for oil, coal and gas of approximately 35, 107 and 37 years, respectively. On this situation researcher are trying to develop new ways to utilize renewable resources as the feedstock for the generation of energy and production of chemical toward negative CO 2 emission and fossil fuel dependency.
Innovations in renewable energy generation e.g. biodiesel are taking the spotlight of new generation. The sharp rise in world biodiesel production has created a glut of glycerol, by-product of saponification or the process of soap making and transesterification or the production of biodiesel. In order to improvise the biofuel economy and put this waste stream to good use new catalytic route must be found. Glycerol can be accounted for 10% of the by-products of biodiesel production. Since for each gallon of biodiesel produces approximately 0.75 lb of glycerol, so this would be a very practical to use glycerol for production of fine chemicals or clean fuel such as hydrogen. To meet the commercial target the oxydehydration of glycerol is one of the most promising options to be focused.
Acrylic acid is one of the most important chemical largely employed by the chemical industry for the production of super absorber, polymer, adhesive, paint, plastic & rubber synthesis, detergent etc. Various catalyst has been targeted for selectively converting glycerol to acrolein, among the supports with Lewis acidity such as α-Al 2 O 3 , SiO 2 and TiO 2 are been applied but the results are not satisfactory. However, metal oxide of 2nd and 3rd transition series e.g. Nb 2 O 5 , WO 3 /ZrO 2 metal phosphates, SAPO's and zeolite are shown quite appreciable selectivity of acrolein. As a general rule, the hydration reaction is favoured at low temperatures, and the dehydration reaction is solution of glycerol was favoured at high temperatures therefore to obtain acrolein, it is necessary to use a sufficient temperature, and/or forward flow to shift the reaction. The reaction may be performed in the liquid phase or in the gas phase; perhaps this type of reaction is known to be catalysed by acids. Production of acrylic acid by direct dehydration followed by oxidation of glycerol takes place by a two-step reaction pathway which involves the formation of acrolein as an intermediate on the appropriate metal catalyst (such as W, Cu, Mn) and finally the oxidation of acrolein to acrylic acid.
Reference may be made to European patent EP 1710227B1, claimed a two-step process which includes dehydration of (˜50 wt %) aqueous solution of glycerol over alumina base catalyst impregnated with phosphoric acid & silica followed by oxidation step over alumina supported Mo—V—W—Cu—O mixed oxide. The process gives acrylic acid yield of 55 to 65%.
Reference may be made to U.S. Pat. No. 7,910,771, the prospective of single step conversion of acrylic acids from glycerol was calmed by Jean-Luc Dubois, Millery, where a single oxydehydration step of glycerol to acrylic acid was described in presence of molecular oxygen, 10-50 wt % of aqueous solution of glycerol was passed over a plate exchanger at 250° C. to 350° C.
Reference may be made to article in the Green Chemistry, 2011, 13, 2954-2962 by F. Cavani et al. where they reports a one pot transformation of glycerol to acrylic acid with a Vanadium incorporated WO 3 catalyst. Under the process condition only 25% yield of acrylic acid was obtained at 280° C. Moreover, the catalyst progressively generate surface V +5 species, which resides in the hexagonal bronze structure of the catalyst, led to a decrease in the selectivity to acrylic acid and to the concomitant rise in carbon oxide formation.
Reference may be made to article in the Journal of Catalysis, 2009, 2, 260-267, in which Ueda et al. and his group reported dehydration of glycerol over vanadium phosphate oxide (VPO) in a gas phase fixed bed reactor at a temperature range of 250° C. to 350° C. At about 300° C. they found 100% glycerol conversion with 3% acrylic acid over VOHPO 4 .0.5H 2 O. With the increment of O 2 /N 2 ratio to 6/18 the acrylic acid formation goes up to 7%, whereas when the reaction temperature rises to 350° C. the acrylic acid conversion goes to the highest of 8%.
Reference may be made to article in the Catalysis Today, 2010, 157, 351-358 in which Japanese worker Ueda and his group reported the production of acroline and acrylic acid through dehydration and oxydehydration of glycerol with mixed FeP—H catalysts. They achieved almost 100% glycerol conversion with 1.2% acrylic acid at 180° C. with a GHSV of 550 h −1 .
The drawback of the processes reported so far is that all of those processes either possess low production of acrylic acid or involve multiple step process under pressurized reaction condition. In the multistep approach it was in evidence that the overall transformation includes a dehydration step to convert glycerol to acrolein which requiring adequate acidity followed by an oxidation step into acrylic acid. To overcome that boundation many researchers trying to develop a new process with a single step catalyst which can selective convert glycerol to acrylic acid in a mild reaction condition. The use of a single bi-functional catalyst aims to meet the challenge for the development of new catalytic approaches to convert glycerol into acrylic acid with a single catalyst.
OBJECTIVES OF THE INVENTION
The main object of the present invention is to provide a single step oxydehydration process to convert glycerol to acrylic acid over nanocrystalline Cu—Mn solid catalyst.
Another object of the present invention is to provide a process, which selectively gives acrylic acid from glycerol under mild condition.
Yet another object of the present invention is to provide a process and catalyst which uses by-product of bio-diesel (glycerol) for future fuel alternatives.
Yet another object of the present invention is to provide a process which works in liquid phase condition without any leaching for the production of acrylic acid from glycerol.
Yet another object of the present invention is to provide a Cu—Mn catalyst and which can be prepared easily to produce acrylic acid from glycerol.
SUMMARY OF THE INVENTION
Accordingly, present invention provides a nanocrystalline Cu supported α-MnO 2 catalyst comprising Cu in the range of 1 to 5 (wt %) MnO 2 in the range of 99 to 95 (wt %) having particle size in the range of 25 to 50 nm.
In an embodiment of the present invention, nanocrystalline Cu supported α-MnO 2 catalyst is useful for single step conversion of glycerol to acrylic acid.
In an embodiment, present invention provide an improved process for the preparation of nanocrystalline Cu supported α-MnO 2 catalyst as claimed in claim 1 and the said process comprising the steps of:
a. mixing of Cu(NO 3 ) 2 .3H 2 O and Mn(NO 3 ) 2 .3H 2 O solution at temperature ranging between 35 to 80° C., where the weight ratio of Cu to Mn ranges between 0.5 to 15; b. adding a surfactant solution drop wise into the solution as obtained in step (a) with constant stirring, where the molar ratio of Cu to surfactant ranges between 0.005 to 0.1; c. adding of reducing agent drop wise into the solution as obtained in step (b) with constant stirring to get a gel where the molar ratio of Cu to reducing agent ranges between 0.5 to 1.5; d. heating the gel as obtained in step (c) at temperature in the range of 100 to 200° C. hydrothermally for a period ranging between 12 to 30 hours to obtain solid followed by washing the solid with excess water; e. drying the solid as obtained in step (d) at temperature in the range of 80 to 110° C. for a period ranging between 6-12 h; f. calcining the solid as obtained in step (e) at temperature ranging between 300 to 800° C. for a period of 6 to 12 hr to obtain nanocrystalline Cu supported α-MnO 2 catalyst.
In another embodiment of the present invention, surfactant used in step (b) is cetyltrimethyl ammonium bromide (CTAB).
In yet another embodiment of the present invention, reducing agent used in step (c) is hydrazine.
In yet another embodiment, present invention provides a process for single step conversion of glycerol to acrylic acid using catalyst as claimed in claim 1 , wherein the said process comprising the steps of:
i. mixing nanocrystalline Cu supported α-MnO 2 catalyst with Cu to α-MnO 2 weight ratio present in the range of 0.5 to 20%, solvent and glycerol followed by adding H 2 O 2 with weight ratio of glycerol to catalyst is in the range of 20 to 200, with molar ratio of glycerol to H 2 O 2 in the range of 1:2 to 1:15 at temperature in the range of 60 to 120° C., while agitating the reaction mixture, for a period in the range of 1 to 30 hr, followed by cooling to at temperature in the range of 25 to 30° C. to obtain acrylic acid.
In yet another embodiment of the present invention, the molar ratio of substrate to H 2 O 2 is preferably in the range 1:2.5 to 1:10.
In yet another embodiment of the present invention, the weight ratio of glycerol to catalyst is preferably in the range of 5 to 20.
In yet another embodiment of the present invention, the conversion of glycerol to acrylic acid in the range of 20-78%.
In yet another embodiment of the present invention, the selectivity of the acrylic acid is in the range of 20 to 84%.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 represents XRD of the prepared catalyst.
FIG. 2 represents SEM images of the Cu—MnO 2 catalyst.
FIG. 3 represents TEM images of the Cu—MnO2 catalyst.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a process for the preparation of nanocrystalline Cu—MnO 2 by hydrothermal synthesis method for the selective single step oxidation of glycerol to acrylic acid in the liquid phase reaction using hydrogen peroxide as an oxidant involves the following steps:
Preparation of the gel composition using Cu(NO 3 ) 2 .3H 2 O, Mn(NO 3 ) 2 .9H 2 O, Cetyltrimethylammonium bromide (CTAB), Hydrazine, H 2 O where Cu(NO 3 ) 2 .3H 2 O and Mn(NO 3 ) 2 .9H 2 O are the precursors for Cu and Mn respectively.
The weight ratio of Cu to MnO 2 varied in the range of 0.05 to 20
The mole ratio of Cu to CTAB varied in the range of 0.75 to 1.5
The pH of the mixture was varied in the range of 9 to 10 by the drop wise addition of aqueous ammonia.
The mole ratio of Cu to hydrazine varied in the range of 0.75 to 1.5
The mixing gel was transferred in a Teflon lined autoclave and kept in an oven with temperature range of 150 to 200° C. for 20-30 h.
The product was filterer with excess water and dried in an oven with temperature range of 100 to 120° C. The dried product was calcined in a furnace in the temperature range of 400-800° C.
Liquid phase selective oxidation reaction was carried out in a two neck Round Bottom flask containing 0.1 g catalyst, 10 ml of solvent and 1 g substrate to which 1 ml H 2 O 2 was added. Then the reaction mixture was stirred at 90° C. for several hours. After completion of the reaction, the reaction mixture was cooled in cold water to room temperature and analyzed by GC fitted with a capillary column and FID detector.
EXAMPLES
The following examples are given by way of illustration and therefore should not be construed to limit the scope of the present invention.
Example 1
In the typical synthesis procedure adequate amount of Cu(NO 3 ) 2 .2.5H 2 O (98%, Aldrich) was dissolved in 4 ml H 2 O along with 5.77 g Mn(NO 3 ).4H 2 O (98%, Aldrich). After the solvation, 1:1 copper to CTAB where added and stirred until a homogeneous solution was obtained. The pH of the mixture was maintained at 9 by the drop wise addition of aqueous ammonia, to the obtained slurry, 1:1 hydrazine was added in respect to Cu. Finally the homogeneous slurry was transferred into an autoclaved for hydrothermal treatment at 180° C. for 24 hrs. The obtained product was washed and dried followed by calcination in static air for 6 h.
XRD, SEM and TEM images of the catalyst are given in FIGS. 1, 2 and 3 respectively.
Example-2
This example describes the production of acrylic acid form glycerol in liquid phase with H 2 O 2 as oxidant over Cu—MnO 2 solid catalyst.
Oxidation of glycerol was carried out in a two neck Round Bottom flask containing 0.1 g catalyst, 10 ml of solvent and 1 g substrate to which 1 ml H 2 O 2 was added. Then the reaction mixture was stirred at 90° C. for 30 hours. On completion, the reaction mixture was cooled to ˜30° C. (room temperature) and analysed by a Thermo GC equipped with a FID.
Process Conditions
Catalyst: 0.02 g
Cu:MnO 2 weight ratio in the catalyst=5:95.
Reaction temperature: 90° C.
Reaction time: 20 h
Product Analysis
Glycerol conversion: 77.1%
Acrylic acid: 74.7%
Example-3
The example describes the effect of temperature on production of acrylic acid form glycerol in liquid phase with H 2 O 2 as oxidant over Cu—MnO 2 solid catalyst. The product analysis presented in Table-1.
Process Conditions
Catalyst: 0.02 g
Cu:MnO 2 weight ratio in the catalyst=5:95.
Reaction time: 20 h
Product analysis
TABLE 1
Conversion (%)
Selectivity (%)
Temperature (° C.)
Glycerol
Acrylic acid
60
71.1
73.9
90
77.1
74.7
120
77.9
62.7
Example-4
The example describes the effect of time on production of acrylic acid form glycerol over Cu—MnO 2 solid catalyst. The product analysis presented in Table 2
Process Conditions
Catalyst: 0.02 g
Cu:MnO 2 weight ratio in the catalyst=5:95.
Reaction temperature: 90° C.
Product analysis
TABLE 2
Conversion (%)
Selectivity (%)
Time (h)
Glycerol
Acrylic acid
6
64.6
61.2
10
70.5
66.3
20
77.1
74.7
30
81.9
81.2
Example-5
The example describes the effect of glycerol to oxidant (H 2 O 2 ) ratio in terms of glycerol conversion and acrylic acid selectivity over Cu—MnO 2 catalyst. The product analysis presented in Table-3.
Process Conditions
Catalyst: 0.02 g
Cu:MnO 2 weight ratio in the catalyst=5:95.
Reaction temperature: 90° C.
Reaction time: 20 h
TABLE 3
Glycerol:H 2 O 2
Conversion (%)
Selectivity (%)
(mole ratio)
Glycerol
Acrylic acid
1:2.5
49.9
73.6
1:5
77.1
74.7
1:7.5
75.6
77.7
1:10
70.1
78.5
ADVANTAGES OF THE INVENTION
1. The process of the present invention prepares a catalyst Cu—MnO 2 by hydrothermal synthesis method in presence of surfactant for the selective oxidation of glycerol to acrylic acid reaction.
2. The process of the present invention is to convert glycerol in to fine chemicals such as acrylic acid in a single step with a single solid catalyst.
3. The process provides not only good conversion but also good acrylic acid selectivity.
4. The process utilizes glycerol (by-product of saponification or the process of soap making and transesterification or the production of biodiesel) to produce acrylic acid, which become the major advantages of this process.
5. The catalyst shows no deactivation and no leaching up to 4 reuse at 90° C.
6. The catalyst is used in very low amounts to obtain very high conversion and acrylic acid selectivity. | The present invention provides a process and a solid catalyst for oxydehydration of glycerol to acrylic acid with H 2 O 2 under mild experimental condition at atmospheric pressure. The process provides a single step liquid phase selective oxidation glycerol to acrylic acid over nanocrystalline Cu supported α-MnO 2 catalyst. The process provides glycerol conversion of 20-78% and selectivity of acrylic acid up to 86%. | 2 |
FIELD OF THE INVENTION
[0001] This invention relates generally to computing environments where users employ keyboards for text, data, document creation and any of a host of other applications, and more specifically it relates to changing the functional keyboard layout to accommodate a specific user's personal keyboard functional equivalence so that the keys on the keyboard of, say, a computer not normally used by the user, will be automatically redefined to match the user's personal preferences and then restored to their original settings when the user is done using the keyboard.
BACKGROUND
[0002] Computer users are familiar with the physical layouts of commonly employed keyboards such as the standard QWERTY or alternatively, the DVORAK layout of keys on the keyboard. However, it is also very common for a given user to establish a profile of personal keyboard functional equivalents for the meaning to be associated with individual keys such as function keys or keys with special shortcut functions.
[0003] Other personal preference changes to the keyboard are related to the language in which the user normally wishes to write or communicate or to specific programming statements that the user may frequently make while using the keyboard to create applications programs or other computer code.
[0004] Indeed, numerous software programs are available either free or for fee downloading that enable a user to customize their own keyboard preferences as evidenced by the many offerings of such software on http://www.bluechillies.com/ specifically created to allow the user to customize their keyboard functional layout. However, if the user is not using his or her own customized keyboard but is using another computer and keyboard say in another office or at another user's station, customizing that other user's keyboard might not be received with pleasure.
[0005] There are several possible solutions to this problem such as manually changing the keyboard functional layout, preferred language or shortcuts that are available to user's running Linux or Windows operating systems, but these require time and effort on the part of the user. Alternatively, the user's own keyboard functional layout preferences could be recorded on a portable data memory medium such as a flashcard or smart card or memory stick to load the user's personal preferences into the computer. Use of a smartcard for such a purpose is shown in U.S. Pat. No. 7,177,915. But this type of solution requires the special smart card or other portable device to be carried about and employed by the user whenever he or she wishes to use some computer other that the one he or she customarily uses and it requires special hardware and software at the other computer to detect and read the smartcard.
SUMMARY
[0006] The present invention solves these problems by providing a method and system that enable a user to store his or her personal keyboard layout preferences and shortcuts in a file in a web account such as email, Google or Yahoo or any web site or service that enables a user to store securely his or her private information for access only when such user logs onto the web site. When the user visits or uses a computer other than the one he or she customarily uses and has already customized with their personal keyboard layout functional preferences, it is an easy thing to simply log on to the website or email server where the user's personal keyboard preference profile has been stored, download it via the browser to the computer being used, and pass it to the operating system of the computer via an Applications Programming Interface (API). The currently-existing keyboard functional layout of that computer can be retrieved from the operating system and sent to the website or email for temporary storage so that the original keyboard layout functions may be restored again once the user is finished using the alternate computer.
[0007] The present invention provides a method, system and program for providing a user of a computer system an easy way to automatically configure the keyboard functional layout of such computer to his or her previously established tastes in choice of keyboard layout, shortcuts, language or any other user-choice variable that may be selected for defining the functions of the keys on a typical computer keyboard. The user first establishes an on-line account such as email or other server access where the user can securely store his or her preferred keyboard functional key assignments. Then, when using a computer not already configured with the user's preferred key assignments, the user can simply log on to the email or other secure web account where his or her personal key assignment functional profile is stored, download it by using the browser in the computer, and pass the new key assignment parameters via an API to the operating system of the computer to configure the keyboard key functional assignments in accordance with his or her profile. The existing keyboard key assignment table is retrieved from the computer and sent to the on line account of the user for safekeeping while the user employs the computer for any tasks he or she desires to accomplish. The system and method of the invention then restores the originally-existing key assignments to the computer when the user logs off the computer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The foregoing and other objects and advantages of the invention will be appreciated more fully from the following further description thereof with reference to the accompanying drawings, wherein:
[0009] FIG. 1 illustrates schematically the block diagram of the elements of a computer system having internet access and shows the general flow of data that allows retrieval of the user's keyboard layout preference profile from an on-line account, passing it to the computer system's operating system (OS), storing the computer's originally-existing keyboard layout preference table in the on line account for safekeeping and restoring this table back to the OS when the user logs off the computer or signs out from the email or other on-line account where the preference profiles are kept; and
[0010] FIG. 2 illustrates the preferred method, process and program of an embodiment of the invention which performs the various tasks schematically depicted in FIG. 1 .
DETAILED DESCRIPTION
[0011] The invention will now be described in detail with reference to a preferred embodiment thereof as illustrated in the Drawings mentioned above.
[0012] The invention provides a simple way for the user of a computer that has not been configured with the user's preferred keyboard functional layout to invoke an automatic process that will save the currently-existing keyboard functional layout or key function assignment table from the computer, retrieve the user's preferred key function assignments that comprise the user's preferred keyboard layout from safe storage, conveniently located in any on-line account where data may be securely stored, and install that preferred key assignment functional table to the computer's OS for use while the user employs the computer. Then, upon the user's logging off the on-line account or ending use of the computer, the originally programmed preferences from the computer are retrieved from on-line storage and restored in the computer, thus returning it to the original state in which the user found it.
[0013] As is well known, the layout of a computer or other keyboard has mechanical, visual and functional or logical aspects. The mechanical aspects relate to the placement and shapes of the various keys of the keyboard. The visual aspects relate to the arrangement of the legends or markings that appear on the keys, and the functional or logical aspects of the keyboard layout relate to the meanings to be associated with activation of the keys, the latter aspect being controlled by software in the OS of the computer.
[0014] Typically, when a keyboard key is activated, the keyboard sends signals to the computer identifying which key has been activated, such as “left-most key of home row”. The meaning to be associated with the activation of such a key is the function of a programmed key assignment table stored in the computer's OS. The table may define that such a key is the letter “a”, or that some entirely different result such as a numeral, an assigned function, or a programming shortcut is to be indicated to the computer system.
[0015] Turning to FIG. 1 , the user is assumed to be at a computer system, 10 , that is not the system normally used or previously configured with keyboard layout preferences by the user. The user logs on to any convenient on-line server or account he or she may have access to by use of the browser 20 in the computer system 10 . When the user signs in to their on line account, the user's personal keyboard preference table of key assignments is retrieved from storage at the server and delivered by the browser 20 to the computer's operating system 40 via an API 30 . The computer's currently existing keyboard layout or preference assignment table 50 is first retrieved by the API and passed to the browser 20 which stores the existing user-preference or key assignment table in the on-line account storage. The system then loads the OS with the user's own preferred keyboard layout profile or key assignment table as retrieved from the on-line account storage, and configures the computer system with the desired keyboard layout for the user.
[0016] Keyboard layout preferences may include choice of language, which itself requires numerous keys to be re-assigned to mean new characters or numbers or punctuation or emphasis characters, may include total re-location of the existing key assignments such as from QWERTY to Dvorak, and/or may include re-assignment of keys normally used for functions such as textual or programming functions, all of which may suit the personal desires of the user more effectively than the existing keyboard layout when the user first begins use of the computer system.
[0017] The process generally described above with reference to FIG. 1 is shown in greater detail in FIG. 2 where a preferred embodiment of the method, process or program of the invention is illustrated in more detail.
[0018] Turning to FIG. 2 , the process begins in box 31 with the user logging on to their on line account at a server or other system where the user has previously securely stored his or her keyboard layout or key assignment preference table. The user retrieves such layout information and the necessary computer programming of the process of the invention by logging on to his or her account as shown by box 32 and, when properly identified, as is customary, the account automatically passes the keyboard layout data and process programming to the browser which in turn passes it as shown in box 33 via the API to the OS of the computer where it may be installed as the new keyboard layout preference table and the computer process of the invention is installed for execution in the OS. However, the process must first preserve the existing keyboard layout or key assignment table, so the process retrieves the existing or “old” keyboard layout table from the OS as shown by box 34 in FIG. 2 . The process then passes the old keyboard layout table to the on-line account via the browser, and the existing keyboard layout data is stored there for later use in restoring the original keyboard layout when the user is finished using the computer system.
[0019] The process continues after establishing the new keyboard layout table in the OS by monitoring in box 36 for the user to sign off of the on-line account, signifying that he or she is finished using the computer system, or, in the alternative, monitors for logoff from the computer system by the user, signifying he or she is finished. When such an event is found, the process first retrieves the old keyboard layout table from the on-line account as shown by box 37 of FIG. 2 .
[0020] Then the process passes the old, or originally-present, keyboard layout table back to the OS as shown in box 38 and, when this is complete, the process ends at box 39 .
[0021] While the process of the preferred embodiment is shown in FIG. 2 as a general flow schematic, it will be easily appreciated that it can be embodied as a computer program using any of a variety of programming languages. It will be appreciated that the keyboard layout table of the user's preferred layout is retrieved from the on line account together with the necessary process code to carry out the method of the invention and installed in the OS of the computer system for execution.
[0022] It is somewhat arbitrary as to whether the computer process first retrieves the old keyboard layout from the OS or loads the new keyboard layout table first, so long as the old or pre-existing keyboard layout table is preserved and passed to the browser and then on to the on line account for secure storage as described. The specific order of these steps may be changed, so long as the principle of preserving the existing functional keyboard layout or table is maintained. The preferred embodiment is written so that the OS receives the new, user-preferred keyboard layout table, retrieves and passes the old keyboard layout table to the browser and then installs the new keyboard layout for use.
[0023] Having thus described the invention with reference to a preferred embodiment thereof, it will be apparent to those of skill in this art that the invention would be implemented in any particular computer system with ease, wherefore the invention as described in the following claims is not limited to any particular computer system or to any particular programming language or technique. | A user visiting a computer other than his or her customary one logs on to a website or email server where the user's personal keyboard preference profile has been stored. The personal preferences are downloaded via the browser to the computer being used, and passed to its operating system via an Applications Programming Interface where the computer can install the personal preference profile as the temporary keyboard layout profile. The original keyboard layout of that computer is retrieved from the operating system and sent to the website or email for temporary storage so that the original layout may be restored once the user is finished. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to energy recovery devices and in particular to devices installed in the exhaust of heating equipment to recover waste heat.
It is known to install a fluid conducting coil in the chimney of a furnace to capture waste heat flowing therein. However, many of these devices restrict the updraft of the chimney. For some chimneys or flues it is not feasible to withdraw a significant amount of waste heat from the exhaust without dangerously reducing updraft. Since the updraft depends upon the operating conditions of the furnace as well as wind conditions, the coil inserted in the flue or chimney ought to be conservatively small to avoid a back pressure that might cause exhaust to leak into the furnace room.
The difficulty of sustaining sufficient updraft is acute for embodiments employing a known double helical heating coil in a chimney. While the double coil is relatively efficient its increased surface area tends to restrict updraft.
Known heat recovery systems have provided alternate exhaust paths, a heat recovery coil being installed in one of these alternate paths. In the latter instance the alternate paths are manually controlled by an operator whenever he wishes to recover exhaust heat. The systems employing alternate exhaust paths do not efficiently extract waste heat since their heat recovery coils are relatively inefficient and must be designed very conservatively to avoid interfering with updraft as conditions change dynamically.
Accordingly, there is a need for an effective heat recovery device which can withdraw a significant amount of waste heat from the exhaust of heat producing equipment. Furthermore, such heat recovery devices ought not to interfere with the normal updraft.
SUMMARY OF THE INVENTION
In accordance with the illustrative embodiments demonstrating features and advantages of the present invention there is provided an energy recovery device for installation in the exhaust of heat producing equipment. The energy recovery device includes a conduit having a main and bypass chamber. A fluid conducting means is mounted within the main chamber for passing fluid therethrough. Also included in the energy recovery device is a relief means for connecting in parallel the main and bypass chambers. The relief means responds to the differential pressure between the main and bypass chamber exceeding a predetermined magnitude.
By employing the foregoing equipment, a device according to the present invention is able to simultaneously achieve two otherwise inconsistent goals: recovering a high percentage of waste heat; and promoting strong updraft. The present invention achieves these goals with a chambered conduit whose flow patterns are altered in response to excessive differential pressures within the conduit.
In a preferred embodiment a cylindrical main chamber contains a nested pair of helical coils mounted with a bypass chamber across the main chamber. These two chambers are multiply connected and may be connected in parallel by the opening of a flap. This flap opens when the differential pressure between the two chambers becomes excessive. Thus, dangerously high back pressure and leaking of exhaust gas is avoided. This response to changing conditions is automatic and thus the updraft and heat recovery operations are kept in harmonious balance.
In the preferred embodiment the nested pair of helical coils have different diameters. Preferably, water is first delivered to the larger outer coil where the exhaust temperature is lower than in the center of the chamber. The two coils may be connected so that the water spirals upwardly throughout the outer coil and then downwardly spirals through the inner coil. It is also preferred that the coils be finned to provide maximum heat transfer between exhaust and water.
An energy recovering device according to the present invention can be installed in many systems and for various applications. For example, the present energy recovery device can preheat the water to a hot water heater. Alternatively, the present energy recovery device may be connected in circuit with a pump and subsurface melting pipes to melt surface ice and snow. In the latter embodiment the system may be connected to an expansion tank which is also a convenient port for adding antifreeze.
Also, for embodiments cooperating with a hot water furnace the heat recovery device may preheat water returning to the furnace to boost its efficiency. Also, it is expected that the heat recovery device can circulate through an external heat exchanger whose output coils are used to preheat the potable water delivered to a hot water heater.
BRIEF DESCRIPTION OF THE DRAWINGS
The above brief description as well as other objects, features and advantages of the present invention will be more fully appreciated by reference to the following detailed description of presently preferred but nonetheless illustrative embodiments in accordance with the present invention, when taken in conjunction with the accompanying drawings wherein:
FIG. 1 is an elevational view, partly in section, of an energy recovery device according to the present invention;
FIG. 2 is a sectional view along lines 2--2 of FIG. 1;
FIG. 3 is a detailed view of a section of the coils in the device of FIG. 1;
FIG. 4 is a schematic illustration of a system employing the device of FIG. 1;
FIG. 5 is a schematic illustration of another system employing the device of FIG. 1; and
FIG. 6 is a schematic illustration of still another system employing the device of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, there is shown an energy recovery device comprising a conduit having a main chamber 10 and a bypass chamber 12. Chamber 10 is essentially a cylindrical housing while bypass chamber 12 is a rectangular housing welded or riveted or other mechanical means to the side of chamber 10. Chambers 10 and 12 are multiply connected at upstream port 14 and downstream port 16, both parts being rectangular openings. It is to be appreciated that other shapes may be employed for main chambers 10 and 12. For example, both may be rectangular or both may be cylindrical. In addition, they may be connected by only one port, but a port sized to allow sufficient bypassing of exhaust from main chamber 10. Also, the dimensions of the chambers may be chosen in accordance with the expected volume of exhaust and the percentage of waste heat to be recaptured.
Also shown herein is a fluid conducting means, which is, in this embodiment, a nested pair of helical coils. These coils include inner coil 18 and outer coil 20 whose central sections have been broken away in FIG. 1 for clarity. Chambers 10 and 12 and coils 18 and 20 have also been sectioned along a central plane. It is also to be noted that inner and outer coils 20 and 18 each comprise nine turns and they have been joined together at their adjacent upper ends at crossover 22.
Inner coil 18 spirals on a circle having a diameter of 3.5 inches while the outer coil spirals on a circle having a diameter of 6.0 inches. In this embodiment main chamber 10 is 18 inches high and has an inside diameter of 12 inches. However, these dimensions can be varied depending upon the volume of exhaust gas, the amount of heat which must be extracted, weight limitations, etc.
While a pair of nested coils is shown herein other structures are anticipated. It is preferred that the chosen structure have piping that follows a serpentine path so that the exhaust is intimately contacted. Thus, for some embodiments the piping may oscillate in an axial direction around or near the circumference of the main chamber. For other embodiments, the coils may spiral inwardly, following a conical surface.
A relief means is shown herein as flap 24 which is essentially a cylindrical section. Flap 24 is hinged at its lower end 26 and is sized to cover port 14. Flap 24 is biased towards a closed position by weight 28 which is threadably attached to screw post 30. Flap 24 is held closed unless the pressure in main chamber 10 exceeds that in bypass chamber 12 by a predetermined magnitude. Upon the opening of flap 24 exhaust gas may enter bypass chamber 12 through port 14 and leave through port 16, thereby avoiding coils 18 and 20.
Exhaust gas enters main chamber 10 by means of coaxial inlet 32 and leaves by means of coaxial outlet 34. In one embodiment inlet 32 and outlet 34 are 8 inches in diameter, although this dimension can be varied depending upon the ducts to which the device of FIG. 1 is coupled.
Fluid such as water may be circulated through coils 18 and 20 by pipes 36 and 38. In embodiments where coils 18 and 20 are used as a preheater for a hot water heater, pipe 36 may operate as a means for delivering potable water to the coils. Preheated water can be drawn from pipe 38 which then operates as a means for transferring water from the coils to the hot water heater. It is to be appreciated, however, that the direction of flow may be reversed. Although it is preferable to deliver water first to outer coil 20 since this coil is normally cooler than central, inner coil 18. Pipes 36 and 38 may be connected in various fashions to different equipment. For example, coils 18 and 20 may supply subsurface melting pipes. In the latter instance pipes 36 and 38 operate as a means for connecting melting pipes and, if desired, a pump.
A pump means is shown herein as water pump 40 which is mounted on bracket 42. Pump 40 has an inlet 44 and an outlet 46, the latter connecting to pipe 36. For most practical embodiments a pump will be employed to increase the flow rate and efficiency of the apparatus of FIG. 1, although it is possible for convection currents to sustain circulation.
Referring to FIG. 2, a downward sectional view along lines 2--2 of FIG. 1 is given. However, in this view flap 24 is shown closed, unlike FIG. 1. When closed, exhaust primarily flows through main chamber 10.
Referring to FIG. 3, a section of pipe from either coil 18 or 20 (FIG. 1) is illustrated in detail. As shown herein the pipe consists of a central conduit 50 having on it a plurality of annular fins 52. This finned arrangement encourages rapid conduction of exhaust heat through fins 52 to conduit 50. In one embodiment the conduit 50 had an inside diameter of 1/2 inch and an outside diameter of 7/8 inch. However, in other applications the dimensions of the pipe and fins may be altered depending upon the volume of exhaust, the amount of heat to be extracted etc.
Referring to FIG. 4, a schematic illustration is given of a system employing coils 18 and 20 of FIG. 1. Coils 18 and 20 are shown serially connected to pump 40. Also coil 18 is shown connected to pressure safety 54. Safety 54 operates to discharge water from the system if its pressure becomes excessive. Safety 54 empties into a floor drain 56. Water supplied by the water mains is schematically indicated by line 58 which connects to the inlet of pump 40 and main inlet 60 of hot water heater 62. The serial combination of pump 40, coils 18 and 20 and safety 54 are connected between main inlet 60 and inlet 64 of hot water heater 62. Auxiliary inlet 64 can be a special inlet or the drain normally found near the bottom of a conventional hot water heater. The outlet from hot water heater 62 is schematically illustrated as line 66.
Referring to FIG. 5, an alternate system is shown wherein coils 18 and 20 (this Figure and FIG. 1) operate to heat subsurface melting pipes. In this embodiment melting pipes are illustrated as a serpentine configuration of pipes 70 and 72. As an example, pipes 70 may be located below the surface of a walk leading to a house while pipe 72 may be below the surface of a driveway leading to a garage. Connected in series are subsurface pipes 70 and 72, pump 40, safety 54 and coils 18 and 20 (identical elements in this and the other Figure have the same reference numerals). Also serially connected with coil 18 is tank 74 having a orifice 76. The system is connected to circulate water and antifreeze in a single circuit, tank 74 being used as a reservoir, orifice 76 as a filling port.
Referring to FIG. 6, a schematic illustration is given of an alternate system using the device of FIG. 1. Heat producing equipment is shown herein as home heating furnace 80 of the hot water type. Furnace 80 has an output flue 82 which couples to apparatus 84 which is the equipment previously illustrated in FIG. 1. Above apparatus 84 is a flue 86 which leads to chimney 88. Installed on flue 86 is a balancing vent 90. This balancing vent relieves any back pressure or leaked exhaust within the furnace room by allowing a draft through vent 90 and up chimney 88. Vent 90 is regulated by balancing flap 92 which is normally biased by a weight (not shown) into the closed position, unless the back pressure in the room becomes excessive. The water heated by furnace 80 is circulated by pump unit 94 which has an output port feeding lines 96 and 98. The return to furnace 80 is through input ports 100 and 102. Lines 96 and 102 are a feeder and return, respectively, for radiators which may be coupled at connection 104. Serially connected to input port 100 is the input circulation feed of heat exchanger 108. Exchanger 108 is a conventional device which isolates the non-potable water in line 100 from potable water in its output feeds. The output feeds of exchanger 108 are serially connected to pump 109. Also serially coupled with the input feed of heat exchanger 108 is safety 54 which is identical to the safeties previously illustrated in connection with FIGS. 4 and 5.
Serially connected between output port 98 and safety 54 are the coils of apparatus 84 (coils 18 and 20 of FIG. 1). In this embodiment lines 98 and 106 are operated as a means of connecting the coils of the apparatus 84 in circuit with ports 98 and 100.
The output circulation feeds of heat exchanger 108 may act as a preheater for a potable hot water system. Under such circumstances, input line 110 operates as a means for delivering potable water while line 112 operates as a means for transferring water to a hot water heater. The connection to a hot water system is effected by connecting lines 110 and 112 to lines 60 and 64, respectively, of FIG. 4.
To facilitate an understanding of the principles associated with the present invention, the operation of the apparatus of FIGS. 1 to 4 will be first described briefly. When the associated heat producing equipment is operating it draws hot exhaust past heating coils 18 and 20 (FIGS. 1 and 4) thereby heating them and the water passing through them. In one embodiment pump 40 is electrically connected in parallel with the electric motor associated with an oil burner. Accordingly, water circulates through coils 18 and 20 only when the furnace is operating. When operating, potable water is pumped from water mains 58 through coils 20 and 18, past safety 54 and into auxiliary input 64 of hot water heater 62. In a conventional hot water heater the water is brought initially to the bottom of the tank and is heated as it rises. Because of the upward circulation, injection of preheated water at lower input 64 does not interfere with the normal operation of a conventional hot water heater.
The equipment of FIG. 5 operates similar to that of FIG. 4 except that heated water is circulated through pipes 70 and 72 and tank 74. This latter system is a closed and continually circulates the same water, which need not be potable, through coils 18 and 20 and pipes 70 and 72, thereby melting surface ice or snow near the pipes. Since the system may employ non-potable water, antifreeze can be added to the system by means of orifice 76 in tank 74. Tank 74, being higher than the other system elements of FIG. 5, also acts as a reservoir to maintain the water level throughout the system.
The system of FIG. 6 operates similarly to the systems previously described, except heat is being supplied to exchanger 108 and furnace 80. Pump 94, normally supplied with furnace 80, is used to circulate hot water not only to radiators associated with furnace 80 but also to the coils of apparatus 84. Essentially, the coils of apparatus 84 are connected in parallel with the radiators that are across connection 104. Consequently, the heating coils of apparatus 84 act to boost the furnace 80. Heat normally lost through flue 86 preheats water returning to furnace 80 through input port 100. Also, the hot water circulated through the coils of apparatus 84 pass through heat exchanger 108 to supply auxiliary heat. For example, a portion of this recaptured heat may be used to preheat the water of a hot water system or a subsurface melting system.
It is to be appreciated that modifications and alterations may be implemented with respect to the apparatus described. For example, various materials may be used such as copper, aluminum, steel, plastic etc. Furthermore, the specific shapes and dimensions may be altered depending upon the particular environment, furnace capacity, the desired percentage of heat recapture, weight limitations, space limitations, etc. Furthermore, the coils disclosed herein may spiral or oscillate in various fashions. In addition, the waste heat recovered by the apparatus of this invention may be used to supply heat to many other devices besides those already described.
Obviously many other modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. | An energy recovery device can be installed in the exhaust of heat producing equipment. The device includes a conduit having a main and bypass chamber. Also included are fluid conducting coils which are mounted within the main chamber for passing fluid therethrough. A relief device operates to connect in parallel the main and bypass chambers in response to a differential pressure therebetween exceeding a predetermined magnitude. Therefore it is estimated that approximately 50-85% of wasted energy through the flue pipe can be recovered and utilized for said system depending upon the size of the unit. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 10/854,123 filed May 26, 2004, the disclosure of which is incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
FIELD OF INVENTION
[0003] This invention relates to continuous digesters for wood chips in the papermaking industry.
BACKGROUND OF INVENTION
[0004] As commonly practiced in the prior art relating to papermaking, wood chips and alkali liquor (white liquor) are pumped into the top of a hydraulic cooking vessel (digester, approximately 180 feet high and approximately 23 feet in diameter) that is operated at high pressure (165 psig) and temperature (325 degrees F.). A chip cooking process proceeds over the time that it takes the saturated chip column to move down through the digester where the discharge rate of the chips to a blow line at the bottom of the digester is matched to the feed rate at the top so as to maintain a constant level and retention time of the chips in the digester.
[0005] In the cooking process (delignification of wood chips), approximately 50% of the organic chip mass is dissolved in the cooking liquor. At 1 to 3 locations above the lower section of the digester, liquor containing the dissolved solids is removed from the vessel by extracting liquor through sets of screens in the circumferential wall of the digester, the screens being aligned with the inner wall of the digester vessel. The screens are 3 to 4 feet in height. The wash screens are the lowest (often the only) set of screens in a continuous digester and are located 10 to 20 feet up from the bottom of the digester. The screen plates are made from stainless steel with multiple slots cut in them that are 0.12 to 0.35 inch wide by 3 to 4 inches long depending on the location in the digester. The liquor that is extracted can be sent to a chemical recovery system where the liquor solids are concentrated and the organic solids burned in a chemical recovery boiler. The chemicals (inorganic solids) are recovered in the bottom of the recovery boiler and re-used to produce white liquor for the cooking process.
[0006] Just prior to discharge from the digester bottom, the chip mass is washed and cooled by cold (120 to 150 degrees F.) filtrate which is generated externally of the digester (from black liquor for example) and introduced into the wash zone of the digester. As much as possible remaining organic/inorganic material dissolved in the cooking liquor is removed from the chip column by a displacement and diffusion wash in the bottom of the digester by extraction of high-dissolved-solids hot liquor through the wash screens. To displace the high-solids hot liquor and to cool the chip mass, cooled black liquor filtrate is added to the bottom of the digester at several locations in the wash zone.
[0007] In some instances, some of the liquor extracted and/or a combination of lower solids liquors (black liquor and/or white liquor) is added to a center pipe (downcomer) in the digester that discharges in the center of the chip column adjacent to a given set of screens. The liquor added to the center pipe at least partially displaces the liquor being pulled through the extraction screens at such given set of screens.
[0008] In summary, the purpose of the wash screens is to remove high solids filtrate from the chip column as it passes these screens by the efficient displacement and diffusion wash with cooler and cleaner liquor added to counter wash nozzles, to ring dilution nozzles and/or to the center of the chip mass via a downcomer that discharges adjacent to these screens. The efficiency of the wash is measured by the extent to which there is maintained optimum low temperature of the chip mass discharged from the digester with concomitant minimization of the cooling of the wash liquor added to the wash zone.
[0009] Because of the nature of the compaction of the chip column, it is difficult to predict and/or control the uniform flow of re-circulation flows or free liquor upflows or downflows through the chip mass in a large diameter continuous digester of the prior art. In the wash zone, there is a tendency for upflows to short circuit up the sides of the digester and for liquor contained in the chip mass to be carried down with the chip mass only to be displaced from the chip mass at the very bottom of the wash zone.
[0010] Temperature and alkali uniformity in the wash zone are impacted by flows at the bottom of the wash zone and in the wash zone of the digester. The temperature and alkali uniformity in the wash zone are key factors in achieving uniform cook (delignification) across the column. Uniform delignification reduces cellulose (pulp fiber) attack, helping to achieve overall maximum pulp fiber strength and yield. Cook non-uniformity across the column profile, with accompanying non-uniform retention of lignin on the individual fibers is a common deficiency of known prior art digesters.
[0011] As noted, in the prior art, The liquor added to the bottom of the chip mass passes through the chip column via paths of least resistance to the wash screens. The wash screens accommodate this process anomaly by removing the most easily removable flow to support the total wash screens flow. This results in poor displacement and diffusion of dissolved solids (poor wash efficiency) in the chip mass to the wash screens and poor heat transfer in some portions of the chip column. The poor wash efficiency causes downstream problems in the brown stock treatment and bleaching processes. The poor heat transfer in the chip column at the bottom of the digester increases the energy costs in these two affected process areas. Also, during operation, individual wash screens tend to plug off completely with the other screens picking up the flow. Continuous digesters are only shut down for maintenance on an annual basis, due to cost of such shutdowns. In some cases it has been observed that one or two wash screens will plug and remain plugged for the remainder of the year only to be unplugged during the annual shut down. The chip column adjacent to plugged wash screens leads to poor wash efficiency and poor heat transfer.
[0012] Thus, the prior art is deficient in that:
[0013] 1. The flow through each of the wash screens is variable and dependent on the path of least resistance flow of wash filtrate added to the bottom of the digester. This is observed physically by the wide variance in wash screen exit nozzle temperatures.
[0014] 2. There is no known current method to control the individual wash screen flow and temperature in order to break up the pattern of path of least resistance flow of cold blow wash filtrate. Further, there is currently no known method to unplug the wash screens other than when the digester is empty during the annual shut down.
[0015] 3. The upflow through the wash zone is operated at higher than optimum for alkali and temperature profile uniformity because of the current inability to manage and maintain an acceptable wash efficiency in the bottom of the digester.
[0016] 4. There is no known current method for adjusting the amount of free liquor upflow through the wash zone in order to maintain uniformity of temperature and alkali in the wash zone where the highest percentage of the cook (time at temperature) is completed with the highest potential for product non-uniformity to be affected. Currently, in the prior art, a higher free liquor upflow is maintained in order to compensate for the non-uniformity of the operation of the wash screens. Whereas this higher free liquor upflow helps to manage the dissolved solids level in the digester discharge, such flow has a negative impact on the temperature and alkali profiles in the wash zone.
SUMMARY OF INVENTION
[0017] In accordance with one aspect of the present invention, the total volume of liquor withdrawn from the digester through the wash screens within the wash zone of the digester is uniformly and automatically distributed between all of the wash screens. To this end, in accordance with the present invention there are installed individual temperature measurement, flow measurement and flow control valves in association with each of the wash screen to control the flow through such wash screen to maximize energy and wash efficiency. Further, this feature provides for sensing of a screen in difficulty and individual isolation of a screen by closing it's flow control valve to allow the down flowing chip column to wipe a screen thereby cleaning and avoiding total plugging of the screen as occurs in the prior art.
[0018] Additionally, in the present invention, there is provided a central downcomer within the digester. This downcomer includes side discharge ports adjacent to the bottom end of the downcomer through which filtrate liquor is discharged into the digester. These discharge ports of the downcomer are disposed substantially radially of the surrounding wash screens such that the discharge streams of filtrate liquor from the ports are directed substantially radially toward the surrounding screens, thereby creating a layer of filtrate liquor flowing perpendicularly from the center of the digester toward all the screens. This flow pattern of liquor filtrate is directed across the downward flow of the chip mass and has been found to break up or discourage formation of upflow/downflow streams of filtrate liquor within the area of the screens.
[0019] As desired, the piping associated with the wash screens may be provided with automatic or manual back flush apparatus to allow reverse flow of filtrate through the screens to assist in clearing a screen that is showing signs of plugging.
[0020] Still further, in accordance with one aspect of the present invention the present inventors have found that reducing the wash zone free liquor upflow ((for example, from about the current 0.25 gpm/ADt/d (US gallons per minute per air dry tonne per day to a 0.007 gpm/ADt/d of free liquor upflow or downflow)), provides improved uniformity of the product leaving the wash zone.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The foregoing, as well as other objects and advantages of the invention will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like reference characters designate like parts throughout the several views, and wherein:
[0022] FIG. 1 is a schematic representation of a typical wood chip digester embodying various of the features of the present invention;
[0023] FIG. 2 is a schematic representation of a portion of the digester depicted in FIG. 1 and taken along the circle 2 of FIG. 1 ;
[0024] FIG. 3 is a schematic representation of various piping elements and flow directions of fluids into the digester from a downcomer and out of the digester via control elements associated with the present invention; and
[0025] FIG. 4 is detailed side view of the distal end of a downcomer as depicted in FIG. 1 .
DETAILED DESCRIPTION OF INVENTION
[0026] In the embodiment of the present invention depicted in FIGS. 1 and 2 , as noted hereinabove, approximately 50% of the organic chip mass 10 is dissolved in the looking liquor. The depicted digester 14 includes an upper zone 13 into which the chip mass is loaded. This is also the cooking zone. A set 16 of screens, twelve screens 18 in a typical embodiment, are disposed about the inner circumferential wall 20 of the digester at a location just below the cooking zone 13 and above a wash zone 24 which is disposed at the bottom end of the digester.
[0027] Liquor containing dissolved solids is extracted from the interior of the digester through the screens. The liquor extracted through the individual screens is conveyed to a discharge header 28 which encircles the girth of the digester externally of the digester in the region of the screens and is conveyed, as by a pump system 30 , to a chemical recovery station 32 or is selectively returned in part to the digester via a downcomer 54 . As desired, a heater may be interposed within the piping between the pump station and the downcomer to heat the filtrate prior to its return to the digester. The downcomer is located centrally of the digester and includes discharge ports 38 adjacent the lowermost end of the downcomer. As depicted in FIG. 1 , these ports are disposed substantially radially equidistant from the surrounding screens such that the filtrate liquor discharged through the ports is directed substantially radially outwardly (see arrows of FIG. 1 ) from the downcomer ports thereby ensuring that the filtrate liquor discharged from the downcomer flows simultaneously and substantially uniformly radially toward all of the screens. When the filtrate liquor discharged into the chip mass adjacent the wash screens is heated to about the cook filtrate liquor temperature, and by reason of the radially lateral flow of the discharge filtrate liquor, upflow or downflow of the liquor through the chip mass in the area of the screens is prevented or discouraged.
[0028] As needed or desired, black liquor from one or more known sources in a papermaking facility may be added to the filtrate liquor which is extracted from the screens and fed to the downcomer.
[0029] In the depicted digester, there is provided a single set 16 of wash screens includes multiple separate screens 18 covering the digester circumference. As noted, these screens serve to permit the withdrawal of hot liquor containing dissolved organic/inorganic solids from the digester for reuse or recovery of the individual components of the extracted filtrate. In accordance with one aspect of the present invention, and referring to FIGS. 1 and 2 , conveyance of extracted filtrate from each screen 18 is effected by means of a stub pipe 26 disposed behind each screen 18 and serves to accept the liquor extracted from the digester by the screen and to convey the same away from the screen. This stub pipe is in fluid flow communication with a discharge ring header 28 which encircles the digester outside of and along the outer wall 42 of the digester and which serves to convey the filtrate from the several screens to a pump station.
[0030] With specific reference to FIGS. 2 and 3 , in accordance with the present invention, a continuous digester 14 having a set 16 of screens 18 disposed about its inner circumference 20 for withdrawal from the digester through the screen solids-bearing hot liquor, is provided with a combination of elements associated with the stub pipe 26 which is in fluid communication between each screen and a generally circular discharge collection header 28 disposed externally about the outer circumference of the digester. In the depicted embodiment of the invention, these elements are interposed along the length of the stub pipe and between the outer wall of the digester and the header. Each such combination of elements includes a first manual valve 50 located adjacent the digester outer wall, a temperature sensor 52 next to the first manual valve, an electronically controlled valve 54 next to the temperature sensor, a flowmeter 56 next to the electronically controlled valve, and a second manually operated valve 58 adjacent the header. As seen in FIG. 1 , the header is in fluid communication with a pump 30 which functions to draw the hot liquor extracted by each screen through the header to remote locations such as a chemical recovery station 32 , etc.
[0031] FIG. 3 schematically depicts the combination of elements referenced above and shows the association of a combination of elements associated with each individual screen. In this FIG. 3 , the valves associated with back wash of each screen, as seen in FIG. 2 , have been omitted for purposes of clarity.
[0032] In the present invention, hot liquor extracted from the digester through a given screen flows through the combination of elements which are interposed between the digester and the header. In the depicted embodiment, the discharge flow of hot liquor initially encounters the first manual valve 50 . This valve is manually operable to provide a means for manually adjusting the outflow from a given screen to either full flow, partial flow, or no flow. Next in line, the discharge flow encounters the temperature sensor 52 which includes an electrical lead 60 that passes to a controller 62 . Next in line, the discharge flow encounters the electronically controlled valve 54 having an electrical lead 64 that passes to the controller. Next in line, the discharge flow encounters the flowmeter 56 which also includes an electrical lead 66 which passes to the controller. Finally in line, the discharge flow encounters the second manually operated valve 58 and then flows into the header 28 . In the depicted embodiment there is provided a conduit 68 which intersects the stub pipe at a location between the flowmeter and the second manual valve. This conduit is provided with a third manually operated valve 70 .
[0033] Operationally, the first manually operated valve 50 functions to allow manual control over the flow through the stub pipe (irrespective of direction of flow) as either full flow, partial flow or no flow. Thus, this first valve functions as a type of override to any automatic control over the flow between the digester and the header, and in a backwash situation to assist in the flow control of backwash liquid to a screen. For back washing of a screen, the automatic control of the flow of discharge liquor from the screen toward the header is deactivated (as by the controller), the second manual valve 58 is closed to close off all flow to the header, and the third valve 70 is opened to admit backwash liquid into the stub pipe, thence to the screen at a flow rate which can be selected by either or both of the first and third manual valves.
[0034] During normal operation of the digester, with the second and third manual valves closed, and the first manual valve open, the outflow of hot liquor through each of the screens of the set of screens is selected automatically via the controller. Specifically, as hot liquor is withdrawn through a given screen, under the influence of the pump 30 , this discharge liquor encounters the temperature sensor 52 which senses the temperature of the discharge flow and develops an electrical signal which is representative of such flow and transmits such signal to the controller. Like signals representative of the temperature of the discharge flow from each of the screens are fed into the controller where these temperatures are compared to one another and to a temperature which is representative of the desired flow from each screen and which serves as a standard against which each of the discharge flows of each of the screens is compared. Variations in the temperature of the discharge flow from a given screen from the standard temperature are indicative, first, of the existence of flow from the screen, and, second, of the possible existence of cool upflow liquor from the wash zone reaching the screen without passing through the chip mass as a disbursed stream.
[0035] After the discharge flow passes the temperature sensor, it encounters the electronically controlled valve 54 which functions to adjust the rate of discharge flow to a value which is determined by the controller.
[0036] Downstream of the electronically controlled valve, the discharge flow encounters the flowmeter whose function is to sense the rate of flow of the discharge liquor through the stub pipe, generate an electrical signal representative of the sensed rate of flow and transmit such signal to the controller via the electrical lead 66 .
[0037] From the foregoing, it will be evident that if a screen is fully plugged, all flow of hot liquor through the screen will be halted. In this event, the there is no flowing hot liquor to contribute to the temperature sensed by the temperature sensor so this sensor will report to the controller a relatively cool temperature. Within the controller this cooler temperature will be compared to the normal hot liquor temperature, or other set temperature, and generate a signal to the operator to alert the operator to this undesirable condition. Likewise, the flowmeter will signal the controller that there is no flow through the stub pipe, this condition also possibly being the result of a plugged screen. In the present system, to avoid actual full plugging of a screen, the controller may be set to alert the operator when there is only a small drop in the temperature of hot liquor and/or small drop in the flow rate of the hot liquor passing through the stub pipe so that the operator may take remedial action immediately to remedy the plugging of the screen. This combination of a reduction in the anticipated flow rate through a stub pipe as sensed by the flowmeter which also sends to the controller a signal representative of such reduced flow to the controller, with the sensed reduction in temperature of the flowing hot liquor provides a novel improved concept for monitoring the operability of each individual screen. Thus, the signal from the flowmeter provides the controller with a signal, which compliments the signal to the controller from the temperature sensor.
[0038] In like manner, if the temperature within the stub pipe is within a range recognized by the controller as acceptable, but the flow rate of hot liquor through a given stub pipe increases above a standard value set in the controller, such conditions may indicate that more than anticipated hot liquor is flowing through the given stub pipe. This condition can be indicative of the lack of contribution to the overall desired discharge rate of hot liquor from the digester by one or more of the other screens, for example, and an alert to the operator to at least investigate the digester operating conditions and, if needed, take remedial action. Thus, it is seen that the combination of the temperature sensor and the flow meter are essential to the successful functioning of the present invention.
[0039] Further, if the rate of flow of hot liquor through the stub pipe is within a range set in the controller, but the temperature of the flow of hot liquor is lower than anticipated, such condition may be indicative of relative cool wash liquor moving upwardly of the digester into the area of the screens, such flow of cool wash water being possibly due to too much wash water being added to the bottom end of the digester or the existence of excess upflow of the wash liquor to a given screen or screens.
[0040] Other combinations of sensed temperature and independently sensed flow rate may be indicative of other operating conditions within the digester which may call for operator interdiction. For example, since the flow of hot liquor from each screen is monitored, both for temperature and flow rate, independently of every other screen, it may be readily determined if one or more screens is not functioning as desired, and importantly, which one or more screens is involved, thereby localizing a malfunction within the digester.
[0041] The present invention provides prompt and early indication of a source of possible trouble with respect to the outflow of hot liquor from the digester. In this respect, if a given screen or screens is noted to be plugging, the operator can close down outflow from such screen or screens, thereby allowing the downflowing chip stream to sweep the surface of the screen interiorly of the digester and remove all or part of any material which is attempting to plug the screen or screens. If this technique is unsuccessful, the operator further has the option of back washing the screen or screens individually employing the first, second and third manually operable valve which are associated with the stub pipe of each screen.
[0042] In accordance with one aspect of the present invention, hot liquor withdrawn from the digester through the screens and after being subjected to chemical recovery, is reintroduced to the interior of the digester through the downcomer which is aligned with the vertical centerline 74 . In the present invention, contrary to the prior art, the discharge ports in the bottom end of the downcomer are disposed both centrally of the interior of the digester and radially aligned with the screens which surround the downcomer. In this manner, the present inventors provide for the injection into the chip mass of a substantially circular sheet of fresh hot liquor which flows from the downcomer ports radially toward the screens. This flowing sheet of hot liquor has been found to eliminate or substantially discourage the development of upflows or downflows within the chip mass at substantially all points radially between the downcomer and the screens in the digester wall. This effect has been particularly noted in the regions of the perpendicular cross-section of the digester at the level of the screens and adjacent the screens for reasons not fully understood.
[0043] In addition to the recycling of treated hot liquor which has been withdrawn from the digester via the discharge header and fed back into the digester via the downcomer, cold filtrate (below the cooking temperature of the chip mass in the digester) from black liquor sources common in a papermaking facility, may be introduced into the bottom end of the digester as wash liquor as by a pump and associated piping as is known in the art. As desired or needed, such black liquor may be added to the digester through the downcomer, either as a substitute for hot liquor from the chemical recovery station or as an additive to the hot liquor from the recovery station.
[0044] Control over the flow of black liquor into the digester may be controlled through the controller, and a plurality of electrically operable valves, such as valves 73 , 76 and 78 . Each of these, and all others of the electrically operable valves includes a respective electrical lead between the controller and each such valve. In the Figures, the the electrical leads from these and others of the electrically responsive elements are indicated in dashed lines for purposes of clarity, but in all instances these electrical leads extend between the respective valve or element and the controller. What is claimed: | A continuous digester comprises a wash zone having a plurality of individual wash screens disposed about an inner wall of the digester for the withdrawal of co-current downflow liquor from the wash zone. A conduit is connected in fluid communication between each of the wash screens and a collector for co-current downflow liquor withdrawn from the wash zone of the digester. A valve is interposed along the length of the conduit leading from each of the wash screens. The valve is operable between open and closed positions in response to a signal received from a temperature sensor associated with the conduit leading from each of the wash screens. The signal represent changes in temperature of a corresponding co-current down flow liquor through a corresponding conduit wherein a corresponding valve permits adjustment of a corresponding flow rate of liquor through said corresponding conduit to a flow rate that is substantially equal to each of the other flow rates of co-current downflow liquor through each of the other conduits. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a novel amino acid derivative having an excellent active oxygen resistance and exhibiting a good solubility, and an active oxygen-resisting agent comprising the same as an active ingredient.
2. Description of the Related Art
In recent years, various skin disorders and diseases owing to active oxygen species have been reported. For example, it has been known that in aging, canceration, pigmentation and inflammation of the skin by sunlight, especially, ultraviolet light, an active oxygen species deeply participates therein as the cause thereof. Accordingly, if the action of the active oxygen species can be inhibited, it is expected that these disorders and diseases of the skin can be prevented.
Enzymatic antioxidants including superoxide dismutase (SOD), non-enzymatic antioxidants such as ascorbic acid, tocopherol or glutathione, or antioxidant derived from a vegetables, such as tannin are known as substances that inhibits the action of an active oxygen species. However, of these substances, the use of SOD is limited because it is costly and chemically unstable. Also the non-enzymatic antioxidants such as ascorbic acid, tocopherol or glutathione are unstable in many cases, and their effect of inhibiting the active oxygen species is unsatisfactory. The antioxidants derived from the vegetables, such as tannin, are also easily hydrolyzed, and themselves easily oxidized. Accordingly, these substances are problematic in stability in many cases.
Further, in recent years, some investigations have been reported in which a metal ion present in vivo plays a part as a catalyst in the occurrence of the active oxygen species, the occurrence of the active oxygen species is controlled by chelation of the metal ion (for example, Free Radicals in Biology and Medicine, Oxford, Clarendon Press, p. 234, 1989). As a compound having a chelation ability, a disferrioxamine compound is known. Since this compound is, however, too strong a chelator, the balance of the metal ion in vivo is interfered with, and this compound is costly. Besides the disferrioxamine compound, metal ion chelating agents such as 2,2'-dipyridyl, 1,10-phenanthrolene and 2,2'-dipyridylamine have been studied. However, most of these compounds exhibit skin irritation.
Amino acid derivatives which are stable, which show low skin irritation and which have an excellent active oxygen resistance are reported in WO 94/14755 (U.S. Pat. No. 5,594,012). Nevertheless, since the derivatives have a low solubility in a multi-purpose oil solvent such as liquid paraffin or an olive oil, the use thereof is limited.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a novel active oxygen-resisting agent which has an excellent active oxygen resistance and which exhibits a good solubility in an oil solvent.
The present invention relates to an active oxygen-resisting agent containing as an active ingredient an amino acid derivative represented by formula (I). ##STR2## wherein Ar represents a substituted or unsubstituted 2-hydroxyphenyl group or a pyridyl group, said substitution being selected from the group consisting of a halogen atom, a C 1-6 alkyl group, a hydroxyl group, a hydroxy C 1-6 allyl group, a nitro group, a C 1-6 alkoxyl group or a carboxyl group,
R 1 represents a side chain of an amino acid,
X represents --O-- or --NH--,
R 2 represents a C 8-22 alkyl group, and
n represents 0 or 1, or a salt thereof.
The amino acid derivative represented by the above-mentioned formula (I) is a novel compound, which is not described in the literature.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the amino acid derivative represented by the abovementioned formula (I), R 1 includes side chains of acidic amino acids such as glutamic acid, aspartic acid, cysteic acid and homocysteic acid, neutral amino acids such as glycine, alanine, β-alanine, valine, leucine, isoleucine, phenylalanine, tryptophan, threonine, serine, homoserine, tyrosine, cysteine, methionine, glutamine and asparagine, and basic amino acids such as lysine, ornithine, arginine and histidine. The neutral amino acids are preferable, and glycine, alanine and phenylalanine are especially preferable.
When an asymmetric carbon atom is present in the amino acid residue, an optically active substance or a racemic substance is available. Examples of the salt include inorganic acid salts such as a hydrochloride and a sulfate; and organic acid salts such as an acetate, a tartrate, a citrate, a p-toluenesulfonate, a fatty acid salt, an acidic amino acid salt and a pyroglutamate. These may be incorporated as amino acid derivative salts, or the amino acid derivatives and the bases may be incorporated separately to form amino acid derivative salts in the composition.
Within the context of the present invention, the group Ar is a 2-hydroxylphenyl group or a pyridyl group which may be substituted on the aromatic ring by one or more substituents selected from the group consisting of a halogen atom, a C 1-6 alkyl group, a hydroxyl group, a hydroxy C 1-6 alkyl group, a nitro group, a C 1-6 alkoxyl group or a carboxyl group.
The amino acid derivative represented by the abovementioned formula (I) can easily be prepared by conventional methods known to those of ordinary skill in the art. For example, amino acid derivatives maybe prepared by reacting 2-hydroxy aromatic aldehyde such as salicylaldehyde with an amino acid long-chain alkyl ester or an amino acid long-chain alkylamide in the presence or absence of a solvent, and followed by reduction such as by adding thereto a hydrogenation agent such as sodium borohydride. Or, it can also be introduced by reacting a 2-hydroxy aromatic aldehyde with an amino acid to form a Schiff base, adding thereto a hydrogenation agent such as sodium borohydride to obtain N-(2-hydroxy aromatic-l-methylene)amino acid, and then subjecting the same to esterification or amidation. The 2-hydroxy aromatic aldehyde used herein includes salicylaldehyde as well as 2-hydroxy-1-naphthoaldehyde, pyridoxal, 2-hydroxy-4-methoxybenzaldehyde, o-vanillin, 5-bromosalicylaldehyde, 5-chlorosalicylaldehyde, 5-nitrosalicylaldehyde, 3,5-dibromosalicylaldehyde, 3,5-dichlorosalicylaldehyde, 2,3-dihydroxybenzaldehyde, 2,4-dihydroxybenzaldehyde and 2,5-dihydroxybenzaldehyde.
The active oxygen-resisting agent of the present invention may be used by administration directly to a system where active oxygen is generated. Within the context of the present invention active oxygen species include hydoxyl radicals, singlet oxygen, and superoxide radical anions.
Though the anti-active oxygen compounds of the general formula (I) according to this invention may be directly administered to active oxygen generating systems, for example, intravenously, skin-topically, etc., they are usually incorporated in cosmetics such as lotion and cream; pharmaceuticals such as anti-inflammatory agent and antiarteriosclerotic agent; and foods such as edible oil. For use as the anti-skin aging component in cosmetics for example, they should be naturally comprised in an amount producing anti-skin aging activities, and may be comprised in an amount of, for example, 0.1 to 10% of the total weight of the cosmetics. For pharmaceutical use in human bodies, they should be naturally administered in an amount producing an intended effect, and may be administered in an amount of, for example, 0.1 to 1000 mg/day per adult. In order to prevent denaturation or deterioration of foods, they may be similarly added to the foods in an amount of 0.1 to 10% of the weight thereof. Otherwise, the anti-active oxygen compounds according to this invention may be formulated into special anti-skin aging preparations, e.g., in the form of ointment, instead of being incorporated in cosmetics.
Generally, the active agent is applied topically to a surface where active oxygen is generated, such as skin or hair. It is ordinarily to be used by being incorporated in toiletries or a skin external agent. For example, when this agent is incorporated into toiletries as an antioxidant, it may be added in an amount of from 0.01 to 10% by weight, preferably 0.1 to 3% by weight, more preferably 0.5 to 2% by weight. Further, when it is incorporated into a skin external agent, it is appropriate that the amount is from 0.01 to 50% by weight.
When the active oxygen-resisting agent of the present invention is used by incorporation into toiletries or a skin external agent, ingredients which are generally used in toiletries or a skin external agent can be added, besides the active oxygen-resisting agent of the present invention, unless the effects of the present invention are inhibited. Examples of the ingredients which are generally used in toiletries or a skin external agent include urea, ethanol, isopropanol, a polyhydric alcohol, an anionic surfactant, an ampholytic agent, a nonionic surfactant, a cationic surfactant, an oil, a high-molecular compound, an emulsifying agent, a powder and an antibiotic.
Suitable carriers for the composition comprise an oil such a olive oil or paraffin oil.
The form of the toiletries or the skin external agent containing the active oxygen-resisting agent of the present invention is not particularly limited, and this agent may take any form of a solution, a paste, a gel, a solid, a powder and the like. Further, the toiletries or the skin external agent containing the active oxygen-resisting agent of the present invention can find use in toiletries or washing agents such as an oil, a lotion, a cream, an emulsion, a gel, a shampoo, a hair rinse, a hair conditioner, an enamel, a foundation, a lipstick, a face powder, a pack, an ointment, a perfume, a powder, an eau de Cologne, a soap, an aerosol and a cleansing foam, as well as in an agent for preventing or improving skin ageing, an agent for preventing or improving skin inflammation, a bath agent, a hair growing agent, a skin care solution, an antisunburn agent and an agent for preventing or improving a skin roughness due to a trauma, chaps and cracks.
The other ordinary ingredients in toiletries or a skin external agent can be added to the toiletries or the skin external agent containing the active oxygen-resisting agent of the present invention. Examples of the ordinary ingredients in toiletries or a skin external agent include a wetting agent such as sodium DL-pyrolidonecarboxylate or sodium lactate; a chelating agent such as ethylenediaminetetraacetic acid, citric acid, ascorbic acid, maleic acid, succinic acid, cephalin, saccharinic acid, hexametaphosphoric acid, 1-hydroxyethane-1,1-diphosphonic acid, dihydroxyethylglycine or salts thereof, a crude drug; vitamins; hormones; an agent such as an antihistamic agent or a skin astringent; a hair growth accelerator such as cantharis tincture, capsicum tincture, ginger tincture, swertiae extract, garlic extract, hinokithiol, carpronium chloride, pentadecanoic acid glyceride, estrogen or various light-sensitive elements; a beautifier such as arbutin or other hydroquinone glycosides; an antioxidant such as dibutylhydroxytoluene, butylhydroxyanisole, propyl gailate or tocopherol; an animal or vegetable extract such as a placenta extract, elastin, collagen, an aloe extract, a hamamelis extract, a sponge cucumber extract, a camomile extract or a licorice extract; an antiseptic such as cresol derivatives or paraben derivatives; a hormone such as corticosteroid; an amino acid; a softener; a demulcent; a tough improver; a superfatting agent; a viscosity modifier; a pearling agent; an antiinflammatory agent; an ultraviolet absorber; a pH adjustor; a flavor; and a coloring material.
The present invention is illustrated more specifically by referring to the following Examples. However, the present invention is not limited to these Examples. In Examples, the amount was expressed by % by weight of the total weight of the composition.
SYNTHESIS EXAMPLE 1
Synthesis of N-(2-hydroxybenzyl)-L-alanine lauryl ester
L-alanine (2.9 g) was dissolved in 20 ml of a 2-N sodium hydroxide aqueous solution, and 3.5 ml of salicylaldehyde and 0.4 g of sodium borohydride were then added thereto in this order. After the mixture was stirred for 1 hour, 3.5 ml of salicylaldehyde and 0.4 g of sodium borohydride were added thereto again. The mixture was stirred at room temperature for 1 hour, and the insoluble matter was then separated through filtration. The filtrate was extracted with diethyl ether. The pH was adjusted to 6 with hydrochloric acid to obtain 5.8 g of N-(2-hydroxybenzyl)-L-alanine. The resulting N-(2-hydroxybenzyl)-L-alanine (4.6 g) and 8.8 g of 1-dodecanol were added to 150 ml of toluene, and a hydrogen chloride gas was blown thereto up to the saturation. Ten grams of a molecular sieve were added thereto, and the mixture was stirred overnight. After the insoluble matter was separated through filtration, the filtrate was concentrated, and the resulting oil was dissolved in methylene chloride. The mixture was washed with a saturated aqueous solution of sodium chloride. The resulting mixture was dried over magnesium sulfate, and concentrated under reduced pressure to give 8 g of N-(2-hydroxybenzyl)-L-alanine lauryl ester.
High resolution mass spectrum (M+H + ): calculated: 364.2852, found: 364.2849 1 H-NMR, [CDCl 3 ] δ: 0.86 (t, 3H), 1.20-1.38 (m, 18H), 1.37 (d, 3H), 1.55 (m, 2H), 3.42 (q, 1H), 3.63 (6, 2H), 3.93 (dd, 2H), 6.77 (t, 1H), 6.86 (d, 1H), 6.96 (d, 1H), 7.17 (t, 1H)
SYNTHESIS EXAMPLE 2
Synthesis of N-(2-hydroxybenzyl)-L-alanine stearyl ester
The above-mentioned compound was prepared in an analogous manner to Synthesis Example 1.
High resolution mass spectrum (M+H + ) calculated: 448.3791, found: 448.3802 1 H-NMR [CDCl 3 ] δ: 0.86 (t, 3H), 1.19-1.38 (m, 30H), 1.37 (d, 3H), 1.56 (m, 2H), 3.51 (q, 1H), 3.63 (t, 2H), 4.01 (dd, 2H), 6.79 (t, 1H), 6.91 (d, 1H)), 7.03 (d, 1H), 7.18 (t, 1H)
SYNTHESIS EXAMPLE 3
Synthesis of N-(2-hydroxybenzyl)glycine lauryl ester
The above-mentioned compound was prepared in an analogous manner to Synthesis Example 1.
High resolution mass spectrum (M+H + ) calculated: 350.2695, found: 350.2685
SYNTHESIS EXAMPLE 4
Synthesis of N-(2-hydroxybenzyl)-L-phenylalanine lauryl ester
The above-mentioned compound was prepared in an analogous manner to Synthesis Example 1.
High resolution mass spectrum (M+H + ): calculated: 440.3165, found: 440.3165
SYNTHESIS EXAMPLE 5
Synthesis of N-(2-hydroxybenzyl)-L-alanine laurylamide
L-alanine laurylamide (2.5 g) and 1 g of sodium hydroxide were dissolved in 20 ml of methanol, and 1.0 ml of salicylaldehyde and 0.1 g of sodium borohydride were added thereto in this order. After the mixture was stirred for 1 hour, 1.0 ml of salicylaldehyde and 0.1 g of sodium borohydride were added thereto again in this order. The mixture was stirred overnight at room temperature, and the insoluble matter was then separated through filtration. The filtrate was adjusted to a pH of 7 with hydrochloric acid, and concentrated under reduced pressure. The resulting oil was dissolved in diethyl ether, washed with water, and then dried over with magnesium sulfate. After the drying agent was separated through filtration, the filtrate was concentrated under reduced pressure to give 3 g of N-(2-hydroxybenzyl)-L-alanine laurylamide.
High resolution mass spectrum (M+H + ): calculated: 363.3012, found: 363.2972 1 H-NMR, [CDCl 3 ] δ: 0.88 (t, 3H), 1.23-1.35 (m, 18H) 1.50 (m, 2H), 3.13 (q, 1H), 3.27 (t, 2H), 3.91 (dd, 2H), 6.78 (t, 1H), 6.83 (d, 1H), 6.96 (d, 1H), 7.19 (t, 1H)
SYNTHESIS EXAMPLE 6
Synthesis of N-(2-hydroxybenzyl)-L-alanine stearylamide
The above-mentioned compound was prepared in an analogous manner to Synthesis Example 5.
High resolution mass spectrum (M+H + ) calculated: 447.3951, found: 447.3946 1 H-NMR [CDCl 3 ] δ: 0.87 (t, 3H), 1.23-1.36 (m, 30H), 1.38 (d, 3H), 1.51 (m, 2H), 3.23 (q, 1H), 3.33 (t, 2H), 3.97 (dd, 2 H), 6.78 (t, 1H), 6.88 (d, 1H), 7.00 (d, 1H), 7.18 (t, 1H)
SYNTHESIS EXAMPLE 7
Synthesis of N-(2-hydroxybenzyl)glycine laurylamide
The above-mentioned compound was prepared in an analogous manner to Synthesis Example 5.
High resolution mass spectrum (M+H + ) calculated: 349.2855, found: 349.2865
SYNTHESIS EXAMPLE 8
Synthesis of N-(2-hydroxybenzyl)phenylalanine laurylamide
The above-mentioned compound was prepared in an analogous manner to Synthesis Example 5.
High resolution mass spectrum (M+H + ): calculated: 439.3325, found: 439.3316
SYNTHESIS EXAMPLE 9
Synthesis of N-(2-hydroxybenzyl)-L-alanine octylamide
The above-mentioned compound was prepared in an analogous manner to Synthesis Example 5.
High resolution mass spectrum (M+H + ) calculated: 307.2386, found: 307.2377
TEST EXAMPLE 1
Test for an Active Oxygen Resistance
The test was conducted according to the method described in Method in Enzymol., vol. 52, p. 302, 1978 (described also in Test Example 3 of Japanese Patent Laid-Open No. 814,755/1994 and Test Example 3 of WO 94/14755). The outline of the test method was that a homogenized 20-mM phosphate buffer of the whole brain of a C57 black mouse was prepared, a test substance was added thereto, and an absorbance of the mixture was measured. A percent inhibition of lipid peroxidation of the test compound was calculated according to the following formula (II) The results are shown in Table 1.
Percent peroxidation inhibition (%)--
{1-(A.sub.1 -A.sub.3)/(A.sub.2 -A.sub.3)}×100 (II)
A 1 : Absorbance in the addition of the test compound
A 2 : Absorbance before the addition of the test compound
A 3 : Absorbance when the test compound is not added, nor is the heating at 37° C. for 30 minutes conducted.
TABLE 1______________________________________Test compound Percent inhibition (%)______________________________________Compound in Synthesis Example 1 39Compound in Synthesis Example 2 16Compound in Synthesis Example 5 80Compound in Synthesis Example 6 17N-(2-hydroxybenzyl)-L-alanine 6Vitamin C -23Citric acid -15______________________________________
As shown in Table 1, the compounds of the present invention exhibit a higher percent inhibition of lipid peroxidation than vitamin C and citric acid as a multi-purpose antioxidant, providing a high active oxygen resistance.
TEXT EXAMPLE 2
Test for a Solubility
The solubility in the solvent shown in Table 2 when the concentration was 1% by weight was evaluated.
TABLE 2______________________________________Test compound Olive oil Liquid paraffin______________________________________Compound in Synthesis soluble solubleExample 1Compound in Synthesis soluble solubleExample 2Compound in Synthesis soluble solubleExample 3Compound in Synthesis soluble solubleExample 4Compound in Synthesis soluble gellingExample 5Compound in Synthesis soluble gellingExample 6Compound in Synthesis soluble gellingExample 7Compound in Synthesis soluble gellingExample 8N-(2-hydroxybenzyl)-L- insoluble insolublealanineN-(2-hydroxybenzyl)-L- insoluble insolubleglycineN-(2-hydroxybenzyl)-L- insoluble insolublephenylalanine______________________________________
As shown in Table 2, the compounds of the present invention are easily soluble in a multi-purpose olive oil of toiletries or a skin external agent by introducing a long-chain alkyl group, and are also dissolved or uniformly dispersed in liquid paraffin.
TEXT EXAMPLE 3
Organoleptic Test
The compounds were subjected as a skin external agent to organoleptic evaluation by panelists, 10 men and 10 women to estimate the feeling upon use. Table 3 shows the evaluation standard of each evaluation item. Compounds shown in Table 4 were prepared in the organoleptic evaluation.
TABLE 3______________________________________Evaluation item Explanation______________________________________Sticky feeling (face) ⊚: very clean ∘: clean .increment.: sticky x: very stickySticky feeling (hands) ⊚: very clean ∘: clean .increment.: sticky x: very stickyDry and hard feeling (face) ⊚: very smooth ∘: smooth .increment.: dry and hard x: very dry and hardDry and hard feeling (hands) ⊚: very smooth ∘: smooth .increment.: dry and hard x: very dry and hard______________________________________
TABLE 4__________________________________________________________________________ ExamplesTest Compound 1 2 3 Comparative Examples__________________________________________________________________________Compound in 0.1 1.0 5.0Synthesis Example 1N-(2-hydroxybenzyl)- 1.0 5.0 1L-alanineLiquid paraffin 30.0 30.0 30.0 30.0 30.0Diglycerol dioleate 5.0 5.0 5.0 5.0 5.0 5.0Propylene glycol 5.0 5.0 5.0 5.0 5.0 5.0Water balance balance balance balance balance balanceEvaluationSticky ∘ ⊚ ⊚ .increment. ∘ xfeeling(face)Sticky ∘ ⊚ ⊚ ∘ ⊚ xfeeling(hands)Dry and ⊚ ⊚ ⊚ x x ∘hardfeeling(face)Dry and ⊚ ⊚ ⊚ ∘ .increment. ∘hardfeeling(hands)__________________________________________________________________________
As shown in Table 4, the compounds of the present invention were all free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
EXAMPLE 4
A hair growth accelerator having a composition shown in Table 5 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 5______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 3 0.1Carpronium chloride 1Pantotenyl ethyl ether 0.5Diphenhydramine chloride 0.1DL-α-tocopherol 0.1Hinokithiol 0.1Salicylic acid 0.2L-menthol 0.2Glycyrrhetinic acid 0.2Sodium DL-pyrolidonecarboxylate 1Ethanol 50Water balanceTotal 100______________________________________
EXAMPLE 5
Dentifrice
A dentifrice having a composition shown in Table 6 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 6______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 1 0.2Calcium hydrogenphosphate 45Silicic anhydride 5Glycerin 8Sorbitol 10Caroboxymethyl cellulose 1Sodium lauryl sulfate 1.2Saccharin 0.1Pigment suitable amountAntiseptic and pharmaceutical ingredient suitable amountFlavor suitable amountWater balanceTotal 100______________________________________
EXAMPLE 6
Mouth Wash
A mouth wash having a composition shown in Table 7 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 7______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 3 0.2Ethanol 40Polyoxyethylene hardened castor oil 1Glycerin 101-Menthol 0.5Sodium saccharine 0.1Chlorhexidine gluconate suitable amountFlavor suitable amountWater balanceTotal 100______________________________________
EXAMPLE 7
Anti-sunburn Cream
An anti-sunburn cream having a composition shown in Table 8 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 8______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 1 1.2Glycerin 5Stearyl alcohol 1Sesame oil 2Ultraviolet absorber 5Stearic acid 5.5Monostearic acid glycerin 10Antiseptic and antioxidant suitable amountFlavor suitable amountWater balanceTotal 100______________________________________
EXAMPLE 8
Acne Lotion
An acne lotion having a composition shown in Table 9 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 9______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 2 0.01Compound in Synthesis Example 4 0.01Thioxolone 0.01Homosulfamine 0.5Hexachlorophene 0.01d-Camphor 0.021-Menthol 0.051,3-Butylene glycol 5Ethanol 15Flavor suitable amountWater balanceTotal 100______________________________________
EXAMPLE 9
Beautifier
A beautifier having a composition shown in Example 10 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 10______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 2 0.5Arbutin 0.5Vaseline 2.5Liquid paraffin 10Cetostearyl alcohol 12Polyoxyethylene (20 E.O.) sorbitan 7monostearateSorbitan monostearate 1Propylene glycol 5Antiseptic and flavor suitable amountWater balanceTotal 100______________________________________
EXAMPLES 10 to 13
Ointment
Ointments having compositions shown in Tables 11 to 14 were prepared in a usual manner. The products were free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 11______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 3 0.5Bacitracin suitable amountPolymyxin sulfate suitable amountPolyethylene glycol distearate 15Methyl p-oxybenzoate 0.1Vaseline balanceTotal 100______________________________________
TABLE 12______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 2 0.5Ethyl aminobenzoate 10Boric acid 4Zinc oxide 9glycerin 4Beeswax 20vegetable oil balanceTotal 100______________________________________
TABLE 13______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 4 0.5Pyridoxine hydrochloride 1Vaseline 25Stearyl alcohol 25Propylene glycol 12Sodium laurate 1Antiseptic suitable amountWater balanceTotal 100______________________________________
TABLE 14______________________________________Ingredients Amount______________________________________Compound in synthesis Example 1 0.5Hydrocortisone acetate 1Antiseptic suitable amountVaseline 25Stearyl alcohol 25Propylene glycol 12Sodium laurate 1Antiseptic suitable amountWater balanceTotal 100______________________________________
EXAMPLES 14 to 16
Liquid Shampoo
Liquid shampoos having compositions shown in Tables 15 to 17 were prepared in a usual manner. The products were free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 15______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 1 0.1Potassium N-lauroylglutamate 5Potassium laurate 1N-lauroyl-N-methyl-β-alanine sodium salt 5Lauryl ether sodium sulfate 2Lauroyl diethanolamide 3Carboxyvinyl polymer 2Collagen hydrolyzate 1Sodium pyrolidonecarboxylate 6Citric acid 1Squalene 0.5Phenoxyethanol 0.2Methyl paraben 0.1Disodium methylenediaminetetraacetate 0.2Flavor suitable amountWater balanceTotal 100______________________________________
TABLE 16______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 3 1Triethanolamine lauryl sulfate 30Polyoxyethylene (3 E.O.) lauryl ether 5triethanolamine sulfateLauryldimethyl aminoacetate betaine 8Coconut oil fatty acid amide propyl betaine 2Diethanolamide laurate 4Hydroxyethyl cellulose 1Polyoxyethylene (30 E.O.) hardened castor 1oilGlycyrrhetinic acid dipotassium salt 0.2Dibutylhydroxytoluene 0.2Zinc pyrithione 2Disodium ethylenediaminetetraacetate 0.1Flavor suitable amountWater balanceTotal 100______________________________________
TABLE 17______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 4 2Disodium lauryl sulfosuccinate 5Sodium dodecylbenzenesulfonate 3Sodium lauryl phosphate 3Triethanolamine laurate 10Triethanolamine myristate 10Laurylimidazolinium betaine 5Lauroyldiethanolamide 6Propylene glycol 7Lauryldimethylamine oxide 2Antiseptic suitable amountFlavor suitable amountWater balanceTotal 100______________________________________
EXAMPLE 17
Rinse
A rinse having a composition shown in Table 18 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 18______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 1 0.1Liquid paraffin 2Lanolin alcohol 1Vaseline 2Cetyl alcohol 2Glycerin monostearate 2Polyethylene glycol (100) stearate 2Polyoxyethylene (2 E.O.) cetyl ether 1Polyoxyethylene (10 E.O.) octylphenyl ether 0.5Plantalene 1200 ™ (made by Henkel) 1Xanthan gum 0.2Collagen hydrolyzate 3Lauryltrimethylammonium chloride 4Nε-lauroyl-L-lysine ethyl ester hydrochloride 1Citric acid suitable amount1,3-Butylene glycol 5Flavor suitable amountLauryldimethylbenzylammonium chloride suitable amountAntioxidant suitable amountWater balanceTotal 100______________________________________
EXAMPLE 18
Cleansing Foam
A cleansing foam having a composition shown in Table 19 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 19______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 2 3Sodium myristate 15Potassium stearate 20Cetanol 3Lanolin 11,3-Butylene glycol 5Glycerin 10Potassium hydroxide 5Antiseptic 0.1Flavor 0.1Water balanceTotal 100______________________________________
EXAMPLE 19
Lotion
A lotion having a composition shown in Table 20 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 20______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 4 0.1Ethanol 36Citric acid 0.2Zinc p-phenylsulfonate 0.2Dipropylene glycol 3Ethyl aminobenzoate 0.2Menthol 0.3Flavor 0.1Antiseptic 0.1Water balanceTotal 100______________________________________
EXAMPLES 20 to 22
Beauty Cream
Beauty creams having compositions shown in Tables 21 to 23 were prepared in a usual manner. The products were free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 21______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 2 0.1Stearic acid 18Liquid paraffin 2Jojoba oil 0.5Sorbitan monoleate 2Potassium hydroxide 1Sorbitol 6Flavor 0.1Antiseptic 0.1Water balanceTotal 100______________________________________
TABLE 22______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 3 0.2Stearic acid 8Cetyl palmitate 2Cetanol 3Beeswax 1Vaseline 1Liquid paraffin 14Silicone oil 1Polyoxyethylene (20 E.O.) sorbitan stearate 1Triethanolamine 1Propylene glycol 5"Prodew 100" ™ (wetting agent of Ajinomoto) 2Flavor 0.1Antiseptic 0.1Water balanceTotal 100______________________________________
TABLE 23______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 4 0.1Stearic acid 14Beeswax 2Liquid paraffin 1Polyoxyethylene (20 E.O.) cetyl ether 5Polyethylene glycol (25) monostearate 6Allantoin chlorohydroxyammonium 0.1Propylene glycol 5Flavor 0.1Antiseptic 0.1Water balanceTotal 100______________________________________
EXAMPLE 23
Face wash
A face wash having a composition shown in Table 24 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 24______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 1 2Triethanolamine N-lauroylglutamate 25Triethanolamine laurate 5Polyoxypropylene (11) polyoxyethylene (4) butyl ether 6(HLB 7.2)Dibutylhydroxytoluene 0.2Ethanol 3Flavor 0.3Water balanceTotal 100______________________________________
EXAMPLE 24
Cleansing Foam
A cleansing foam having a composition shown in Table 25 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 25______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 2 2Liquid paraffin 35Ceresin 8Beeswax 8Cetyl i-octanoate 4Di(cholesterol, behenyl, octyldodecylalcohol)-N-lauroyl- 2L-glutamateSorbitan sesquioleate 2Polyoxyethylene (20 E.O.) sorbit beeswax 5Sorbitol 5Antioxidant 0.1Antiseptic 0.1Water balanceTotal 100______________________________________
EXAMPLE 25
Emulsion
An emulsion having a composition shown in Table 26 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 26______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 4 0.2Lauric acid 0.1Stearic acid 0.5Cetostearyl alcohol 0.5Glycerin triisooctanoate 4Avocado oil 4Polyoxyethylene (60 E.O.) sorbitan monooleate 1.5Glycerin monostearate 0.5Xanthan gum (2-% aqueous solution) 71,3-Butylene glycol 5Ascorbic acid suitable amountFlavor suitable amountAntiseptic 0.1Water balanceTotal 100______________________________________
EXAMPLE 26
Lipstick
A lipstick having a composition shown in Table 27 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 27______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 2 0.5Beeswax 5Carnauba wax 2Candelilla wax 6Ceresin 7Microcrystalline wax 3Lanolin 8Octyldodecyl oleate 12Isopropyl myristate 8Titanium oxide 2Organic pigment (tar pigment) 5Polyglycerin 1Antioxidant suitable amountAntiseptic and flavor suitable amountCastor oil balanceTotal 100______________________________________
EXAMPLE 27
Hair Conditioner
A hair conditioner having a composition shown in Table 28 was prepared in a usual manner. The product was free from the sticky feeling and the dry and hard feeling, and the feeling upon use thereof was quite satisfactory.
TABLE 28______________________________________Ingredients Amount______________________________________Compound in Synthesis Example 1 0.1Liquid paraffin 2Lanolin alcohol 1Vaseline 2Cetyl alcohol 2Glycerin monostearate 2Polyethylene glycol (100) stearate 2Polyoxyethylene (2 E.O.) cetyl ether 1Polyoxyethylene (10 E.O.) oxtylphenyl ether 0.5Plantalene 1200 ™ (made by Henkel) 1Xanthan gum 0.2Collagen hydrolyzate 3Lauryltrimethylammonium chloride 4Nε-lauroyl-L-lysine ethyl ester hydrochloride 1Citric acid suitable amount1,3-Butylene glycol 5Flavor suitable amountLauryldimethylbenzylammonium chloride suitable amountAntioxidant suitable amountWater balanceTotal 100______________________________________
The novel active oxygen-resisting agent of the present invention has an excellent active oxygen resistance, and exhibits a good solubility in an oil solvent. Further, toiletries or an external agent containing the active oxygen resisting agent remains effectively on the skin, is hardly dropped when coated on the skin or the hair, and has a smooth feeling upon use without providing a dry and hard feeling on the skin and the hair.
As is evident from the above Examples, the anti-active oxygen agents according to this invention produce high inhibitory effects on the action of active oxygen species and can be easily prepared at low costs. They are physically and chemically stable. Accordingly, they can be used in anti-skin aging agents, cosmetics, pharmaceuticals or foods in order to prevent active oxygen species-induced disorders and diseases in human or other bodies as well as denaturation and deterioration of foods. Moreover, some of the anti-active oxygen compounds according to this invention have a UV absorptive power so that they are especially useful in cosmetics or the like.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.
This application is based on Japanese patent application 85133/1997 filed in the Japanese Patent Office on Apr. 3, 1997, the entire contents of which are hereby incorporated by reference. | Provided is a novel active oxygen-resisting agent which has an excellent active oxygen resistance and which exhibits a good solubility in an oil solvent. An active oxygen-resisting agent containing as an active ingredient an amino acid derivative represented by the following formula (I) ##STR1## wherein Ar represents a substituted or substituted 2-hydroxyphenyl group or a pyridyl group, said substitution being selected from the group consisting of a halogen atom, a C 1-6 alkyl group, a hydroxyl group, a hydroxy C 1-6 alkyl group, a nitro group, a C 1-6 alkoxyl group or a carboxyl group, R 1 represents a side chain of an amino acid, X represents --O-- or --NH--, R 2 represents a C 8-22 alkyl group, and n represents 0 or 1, or its salt. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a fixing device of the type to be used for fastening a decorative panel to a metal panel in a face-to-face union. More particularly the invention relates to an improved fixing device which is effectively used such as when a decorative panel serving to line an automobile door is fastened to the inner surface of the door.
Generally, the decorative panel which is used such as in lining the automobile body has its base plate coated on the surface with a sheeting material such as fabric or vinyl leather. When the decorative panel is fixed to the inner side of the automobile door, therefore, there must be retained a relationship that said sheeting material is attached fast on its rear surface to the door. For this reason, the fixing device used for fastening the decorative panel of this type generally has a construction such that it can be inserted on the fitting side of the decorative panel. Prior to the attachment of the decorative panel to the inside of the automobile door, this fixing device is inserted in the decorative panel in such a manner that, when the decorative panel is brought to confront the inside of the door, the engaging portion of the fixing device poses itself just in front of the fitting hole perforated in advance in the inside panel of the door. Then, the fixing device is forcibly driven into tight engagement with the fixing hole as by striking the surface of the decorative panel with a hammer, bringing the decorative panel into fast union with the inside of the door.
The fixing devices of this kind which have been suggested to date have a general construction which comprises a head portion adapted to be attached to the decorative panel and an engaging portion adapted to be engaged with the fitting hole perforated in a metal panel such as the inside sheet of the automobile door. The hear portion has two flanges, one larger than the other, opposed to each other across an intervening neck and the engaging portion has a shaft (or stud) extending from the outer surface of one of said flanges in the axial direction of the neck and shoulder means protruding radially from the outer surface of the shaft. The use of this device is accomplished by inserting the small-diameter flange of said head portion from behind the decorative panel into the fitting hole perforated in said panel until the neck is fully pierced through the hole and the panel is held securely between the small-diameter flange and large-diameter flange, bringing the aforementioned engaging portion to a position directly opposite the fitting hole in the panel simultaneously with opposing the decorative panel face to face to the metal panel as described above and subsequently hammering the shoulder means into hooked engagement with the edge of the fitting hole for thereby immobilizing the decorative panel against the metal panel.
Since the conventional fixing device can be fitted into position from behind the decorative panel and the fast engagement of the device with the metal panel can be accomplished simply by hammering the device from above the surface of the decorative panel overlying the device, the device is not affected in any way by the kind of the sheet-shaped cover and the decorative panel can be joined with the metal panel with ample tightness. Conversely, once the conventional fixing device is fastened to the panel by its engaging portion being driven home in the hole perforated in the panel, the shoulder means which have advanced past the perforated hole are brought into permanent engagement with the edge on the rear side of the hole and the device itself generally possesses no means of breaking this engagement. When there arises necessity for removing the decorative panel as when some built-in parts in the automobile door are to be replaced or given repairs, for example, the fixing device may be broken by removal. If, in this case, the removal of the decorative panel is accomplished simply by breaking the fixing device, then the damage to be suffered may be slight. Since the decorative panel is generally made of a material more brittle than the metal panel, however, it often happens that the decorative panel itself or the edge of the hole perforated in the decorative panel for admitting the head portion of the fixing device is broken sooner than the fixing device.
This invention has been accomplished with a view to solving the various problems described above. It is, accordingly, an object of this invention to provide a fixing device which is so adapted that the fixing device, when driven into a supporting panel of high strength such as a metal panel by the pressure applied from above the surface of a decorative panel in much the same way as the conventional fixing device, enables the decorative panel to be fastened onto the supporting panel and, on the other hand, where there arises necessity for removing the decorative panel from the supporting panel, the engagement between the two panels can easily be broken by forcing a suitable tool into the crack between the supporting panel and the decorative panel and prying the fixing device out of position.
SUMMARY OF THE INVENTION
To accomplish the object described above according to the present invention, there is provided a fixing device which is formed of a synthetic resin material such as polypropylene possessing suitable resiliency and surface slipperiness in combination with rigidity and which consists of a male member adapted to be fitted to a decorative panel and a female member adapted to be fitted to a supporting panel, said two members being so constructed that they are coupled with each other and consequently the decorative panel is fastened to the supporting panel by causing a shaft provided on the male member to thrust into a hollow space formed inside the female member and bringing an engaging portion formed at the leading end of said shaft into fast engagement with a spherical cavity formed inside said hollow space and, conversely, the union of the two members is broken and consequently the decorative panel is removed from the supporting panel by pulling the shaft out of the hollow space.
Another characteristic feature of the present invention resides in having the female member provided axially inside the hollow space thereof with two spherical cavities each adapted to admit the engaging portion formed at the leading end of the shaft of the male member, whereby the male and female members can be joined in a temporary engagement, viz. the female member can be fitted preparatorily onto the male member ready for attachment to the decorative panel by bringing the engaging portion of the shaft into engagement with the first spherical cavity situated closer to the opening of the hollow space and the union of the decorative panel with the supporting panel can be accomplished by inserting the female member into the fitting hole perforated in the supporting panel, pressing the decorative panel down for thereby bringing the female member into fast engagement with said fitting hole and, at the same time, advancing the engaging portion at the leading end of the shaft into the second spherical cavity and coupling the male and female members in a perfect engagement.
BRIEF EXPLANATION OF THE DRAWING
FIG. 1 is a front view of the male member of the fixing device, with the left half portion sectioned.
FIG. 2 is a plan view of the female member of the fixing device.
FIG. 3 is a sectioned view taken along the line III--III of FIG. 2.
FIG. 4 is a partially sectioned explanatory diagram illustrating the right half portion held in a state of temporary engagement and the left half portion held in a state of full engagement.
FIG. 5 is a partially cutaway exploded perspective view of the fixing device of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Now the characteristics of the present invention will be described in full detail with reference to the illustrated embodiment.
FIG. 1 represents a male member 1 of the fixing device according to this invention and FIG. 2 and FIG. 3 represent a female member 2 to be coupled with said male member 1.
The male member 1 is provided with a head portion 5 adapted to be engaged with a pyriform fitting hole 4 perforated in a decorative panel 3 and a shaft 6 adapted to be thrust into engagement with the female member 2. The head portion 5 has a holding flange 8 of a small diameter and a main flange 9 of a large diameter opposed to each other across an intervening neck 7 possessing a circular periphery. The shaft 6 extends perpendicularly from the lower surface of the main flange 9, opposite neck 7, in the axial line of the neck 7 and terminates in a bulbous engaging portion 10.
The pyriform fitting hole 4 perforated in the decorative panel 3 is formed of a circular hole 4a of a large diameter and a circular hole 4b of a small diameter which are partially joined with each other. The large-diameter hole 4a has a diameter which is greater than the diameter of said small-diameter holding flange 8 and smaller than the diameter of said large-diameter main flange 9. The small-diameter hole 4b which is partially joined with said large-diameter hole 4a has a diameter which is smaller than the diameter of the holding flange 8. The constriction 4c across which the two holes 4a, 4b communicates with each other has a dimension sufficient in size to permit passage of the neck 7 of the head portion 5.
The male member 1 is fastened to the fitting hole 4 by inserting the holding flange 8 from one side (actually the reverse side) of the decorative panel 3 into the large-diameter hole 4a until the main flange 9 collides into the panel surface and then causing the male member in its entirety to slide sidewise in the direction of the small-diameter hole 4b for thereby advancing the neck 7 past the constriction 4c into the small-diameter hole 4b and enabling the decorative panel to be held securely by the holding flange 8 and the main flange 9 because of the intimate contact of the opposite surfaces of the panel with said two flanges. In this case, the present embodiment equalizes the length of the neck 7 with the thickness of the decorative panel to enable the opposed surfaces of the holding flange 8 and the main flange 9 to come into effective planar contact with the opposite surfaces of the decorative panel, lest the head portion already received in the small-diameter hole 4b should not readily move out into the large-diameter hole 4a. Futher with a view to ensuring safe planar contact of the main flange 9, this embodiment provides the main flange on the outer periphery thereof with resilient pieces 9a, 9b protruding diagonally in the upward direction and separates the lower surface of the holding flange 8 and the leading ends of the resilient pieces 9a from each other by a vertical distance smaller than the thickness of the decorative panel 3 so that the extremities of said resilient pieces 9a will be resiliently pressed against the panel surface to have the decorative panel squeezed with added pressure between the main flange and the holding flange 8.
When the holding flange 8 is thrust into the large-diameter hole 4a and then moved sidewise into the small-diameter hole 4b in the process of fitting the male member 1 to the decorative panel 3, the handler at work is required to pinch the male member 1 by the shaft 6, press the upper surface of the main flange 9 against the decorative panel 3 with force enough for the resilient pieces 9a, 9a diagonally protruding from the outer periphery of the main flange to bend out temporarily against their resilience and then move the male member in situ in the direction of the small-diameter hole 4b. Then after the neck 7 has settled in its fixed position, the pressure exerted on the main flange is released. Consequently, the resilient pieces 9a, 9a act upon one side (reverse side) of the decorative panel 3 and squeeze the decorative panel in cooperation with the holding flange 8 now held on the other side of the panel, with the result that the male member is prevented from enjoying freedom of movement from said fixed position.
When the male member is attached to the decorative panel 3 as described above, the resilient pieces 9a provided on the main flange 9 are pressed against the one side of the panel and the male member 1 is consequently fastened to the panel by the panel itself being held securely between the main flange 9 and the holding flange. The squeezing force with which the decorative panel is held fast is such that even in the presence of a gap between the edge of the small-diameter hole 4b of the pyriform fitting hole 4 and the neck, said resilient pieces 9a function effectively to keep the male member securely in position and prevent it from freely moving out of position. When the fixing device is used to fasten the decorative panel to the metal panel on the automobile body, therefore, there is no possibility of the fixing device readily falling out of the fitting hole or moving out of position under external force. Thus, the fixing device of this invention can be used in a stable state at all times.
Since, in the fixing device of this invention, said resilient pieces 9a are extended from the outer periphery of the main flange 9 in the radial directions parting from the neck 7 of the head portion 5 and are adapted to act uniformly upon the lower surface of the holding flange 8, they enable the shaft 6 to be held constantley perpendicuar to the decorative panel 3 and consequently to be disposed perpendicularly relative to the fitting hole perforated in said panel for engagement with the shaft. In the illustrated embodiment, one pair of such resilient pieces are symmetrically disposed on the neck. When necessary, three or four such resilient pieces may be equiangularly disposed on the outer periphery of the main flange so as to extend radially in three or four directions.
The female member 2 with which said male member 1 is to be coupled has, as its main body, a hollow barrel 11 substantially of the shape of an inverted cone and it has an annular fitting flange or head 13 provided on the periphery of the opening 12 of said barrel 11 and a plurality of shoulder means 14 provided on the outer surface of the barrel 11 in such a manner as to be axially spaced from and opposed to the lower surface of the annular fitting flange 13. In the depth of the empty space embraced in the barrel 11, two spherical cavities 15, 16 are disposed each adapted to engage the bulbous engaging portion 10 formed at the leading end of the shaft 6 of the male member 1.
The barrel 11 of the female member in the present embodiment is so formed that the largest outside diameter thereof at the opening 12 is equal to or slightly smaller than the inside diameter of a hole 18 perforated in a supporting panel 17. Conversely, the shoulder means 14 protrude from the outer surface of the barrel 11 so that their outermost radial extent falls on an imaginary circle having a diameter greater than the inside diameter of said hole 18. The extremities of the shoulder means 14 closer to the barrel 11 are separated from the lower surface of the fitting flange 13 to form a gap or groove 19 for admitting the edge of said hole 18 between said extremities and the fitting flange 13.
The bore in the barrel 11 is formed with a depth sufficient to accept the entire length of the shaft 6 of the female member inclusive of the bulbous engaging portion 10. On the inner wall of this bore in the barrel there are provided three raised axially extending ribs, each of a profile designed to form said spherical cavities 15, 16 which are formed equidistantly in the axial direction of the barrel.
The raised ribs 20 are situated substantially at the center of the depth of the empty bore as illustrated in FIG. 4. Each of the raised ribs consists, in the direction from the opening 12 side toward the inside bottom of the barrel 11, of an inclined face 20a oriented toward the inside bottom, a face 20b parallel to the axis of the barrel 11, a concavely arcuate face 20c, a face 20d parallel to the axis and a semi-arcuate face 20e inclined toward the inside bottom of the barrel in the manner of a continued range of mountains. The three raised ribs are disposed substantially parallel and circumferentially spaced at fixed intervals on the inside wall of the barrel 11, whereby the three parallel faces 20b jointly form a substantially annular step, the three arcuate faces 20c form a substantially spherical (first) cavity 15, the three parallel faces 20d form a second annular step and the three arcuate faces 20e form in conjunction with the inside bottom of the barrel a spherical (second) cavity 16. Further, the inclined faces 20 a in the portions of said raised ribs 20, closest to the opening 12, jointly form a guide portion which serves to guide the engaging portion 10 formed at the leading end of the shaft 6 of the male member 1 into the cavity 15 formed as described above.
The two cavities 15, 16 are defined by said arcuate faces 20c and 20e which fall on imaginary spheres spacious enough for admitting the bulbous engaging portion 10 of the male member. The engaging portion 10 which is pushed into the empty bore of the barrel 11 through the guide portion formed by the inclined faces 20a spreads out the step formed by the parallel faces 20b and enters the first cavity 15 to be retained therein. As the shaft 6 of the male member 1 is further pushed into the bore of the barrel 11, the engaging portion 10 spreads out the second step defined by parallel faces 20d and enters the second cavity 16 to be held fast therein. In this case, in order that greater resistance is offered to the engaging portion 10 when the engaging portion enters the second cavity 16 than when it enters the first cavity 15, i.e. that the second cavity exerts greater holding strength upon the engaging portion than the first cavity, the present embodiment has said raised ribs so formed that the relative diameter of the second step is slightly smaller than that of the first step.
In this embodiment, the shaft 6 of the male member is so formed that its base portion 21 which joins the main flange 9 has an outside diameter equal to or slightly smaller than the inside diameter of the opening 12 of the barrel 11 of the female member 2. Along in the middle of the entire length of the shaft 6, the outside diameter is gradually decreased downwardly. The tapered portion of the shaft 6 terminates in a small neck 22 which is joined to the shaft 6 and the enlarged generally spherical engaging portion 10. This small neck 22 defines a diameter smaller than the diameters of the first and second steps formed inside the bore of the barrel 11, so that the small neck will never spread out these steps after the engaging portion 10 has entered the cavities 15, 16. The base portion 21 has a length equalling the axial distance between the two cavities 15, 16 so that it will be positioned outside the opening 12 when the engaging portion 10 is received tightly in the first cavity 15 and it will be completely stowed inside the opening when the engaging portion is shifted into the second cavity 6.
The female member 2 which is generally complementary to the male member 1 may be attached to the hole 18 perforated in the supporting panel 17 by inserting the barrel 11 thereof into said hole 18 and then pressing it down until the lower surface of the fitting flange 13 contacts one surface of the panel 17 and the shoulder means 14 formed on the outer surface of the barrel advance past the entire thickness of the panel. As the female member is thus inserted into the hole 18, the shoulder means 14 which have slid past the panel substantially regain their original shape and sizes behind the panel by virtue of resiliency and come into hooked engagement with the edge of the hole, said hooked engagement serving to preclude possible separation of the female member 2 from the panel. Consequently, the female member 2 is fastened securely to the supporting panel.
The preferred method of fastening a decorative panel to the supporting panel by use of the fixing device of this invention constructed as described above will now be explained. First, the head portion 5 of the male member 1 is set into the pyriform fitting hole 4 by the method described above, with the shaft 6 protruding from the surface of the decorative panel. Then, a female member 2 is positioned adjacent each shaft 6 in such a manner as to almost embrace the shaft and then pushed axially to have the shaft 6 received inside the barrel 11, with the engaging portion 10 at the leading end of the shaft led in by the guide portion formed of the raised ribs on the inner wall of the barrel 11, until the engaging portion 10 snaps into fast engagement with the first cavity 15, thereby bringing the male and female members into temporary union. After the two members have been brought into temporary union as described above, the barrel 11 of each female member 2 is inserted into a hole 18 perforated in the supporting panel 17. By means of impacts produced on the surface of the decorative panel 3 such as with a hammer, the female member 2 is driven home and fastened to the hole 18 and, at the same time, the engaging portion 10 received previously into temporary engagement inside the first cavity 15 is pushed further into the second cavity 16, bringing the two members into permanent union. Consequently, the decorative panel 3 is fastened to the supporting panel 17.
Because use of the fixing device of this invention enables the male member 1 to be attached to the rear surface of the decorative panel and the female member 2 to be also joined with the male member 1 in the form of temporary engagement, it follows that desired fastening of the decorative panel to the supporting panel can be accomplished by a very simple procedure of groping for and locating the hole 18 perforated in the supporting panel, inserting the barrel 11 of the female member into the hole 18 and subsequently striking the surface of the decorative panel for thereby driving the shaft 6 of the female member into the barrel 11. Particularly in the case of a part consisting of two members such as those of the fixing device of this invention, the fact that the two members can be joined in advance proves high convenient for the sake of management of parts. The work of first causing a plurality of female members to be attached in advance to as many male members and subsequently pushing all the coupled fixing devices at once into the holes perforated in the supporting panel is slighty more efficient and more convenient than the work which generally requires the plurality of fixing devices to be pushed and fastened one after another into the holes perforated for the purpose of attachment of one decorative panel. In the actual work, the fixing device of this invention is attached to the hole perforated in the supporting panel, with its male and female members kept in a coupled state. Because of the particular construction of the female member, however, the final fastening of the fixing device can also be accomplished by first attaching the female member alone to the hole and then bringing into engagement with this female member the male member which has been fitted in advance to the decorative panel.
Because, in the fixing device of this invention, the engaging portion 10 provided at the leading end of the shaft of the male member 1 is formed in a generally spherical shape and the two cavities 15, 16 provided inside the barrel 11 of the female member 2 for accepting said engaging portion 10 are each formed in a spherical shape corresponding to the shape of the engaging portion, a pull given to the shaft with a force equalling the force exerted at the time of engagement enables the engaging portion to move out of the cavity and slide over the step encircling the entrance to the empty space inside the barrel 11. Consequently the two members can be separated and the decorative panel can be removed from mounted position on the supporting panel. Of course in this case, the separation of the two panels necessitates inserting a suitable tool in the crack between the supporting panel and the decorative panel and prying one panel off the other panel. The fact that the decorative panel can be removed provides access so the parts used inside the door can be replaced, inspected and otherwise handled with much greater ease and convenience than the conventional fixing device of the same class.
Further, the fixing device of the present invention is so constructed that when the engaging portion 10 at the leading end of the shaft previously brought into temporary engagement in the first cavity is pushed further into the second cavity to be retained more securely therein, the base portion 21 of the shaft 6 is stowed completely inside the opening of the female member to fill up the empty space therein, prevent the barrel from bending inwardly and preclude possible release of the shoulder means 14 . Thus, the female member can never escape from the hole in the supporting panel unless the union of the male and female members is broken. The fixing device, accordingly, ensures fast attachment of the decorative panel.
In the preferred embodiment described above, the raised ribs 20 each in the shape of a range of mountains are formed along the axial direction of the barrel 11 for the purpose of providing two cavities 15, 16 inside the bore of the barrel of the female member. The particular disposition of said raised ribs eliminates the problems involved in the fabrication of the female member and aims to provide effective expansion of the barrel during the insertion and extraction of the engaging portion 10. This invention is not limited to this embodiment. For example, a modification aimed at providing the two cavities as by forming continuous annular steps of a cross section resembling that of a wave at fixed intervals in the axial direction on the inner wall of the barrel does not contradict the object of the present invention. Permissibility of such a modification also applies to the shoulder means which are provided on the outer surface of the barrel. A shoulder means formed in the shape of an annular step, not shown, at a position corresponding to that of the fitting flange 13 can bring about substantially the same effect as that produced by the shoulder means of the embodiment described above. In short, all the raised ribs formed on the inside wall of the barrel, are designed to take into consideration both the ease of release from metal dies used at the time of fabrication and with a view to facilitating the elastic deformation during the attachment of the female member to the hole in the supporting panel and during the union of the female and male members. | A fixing device including a male member adapted to be fixed to a decorating panel and a complimentary female retaining member adapted to be attached to a supporting panel. The male member is provided with a head portion having a holding flange of one diameter and a main flange of a larger diameter maintained in space relation whereby the male member is fixed to the decorative panel by inserting the holding flange into a key slot type aperture. The male member includes a shaft extending from the lower surface of the main flange and further includes a terminal bulbous engaging portion. The female member is provided with a hollow barrel body having a flanged head at the open end of said barrel and shoulder means for retaining the barrel in an aperture support panel. The female member is further provided with a plurality of axially extending ribs defining a first and second spherical cavity in spaced relation and adapted to accept the bulbous engaging portion in two axially spaced positions. | 5 |
This application is a Continuation-in-Part of copending application Ser. No. 365, filed on Dec. 29, 1978, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a pressure-sensitive record material. More particularly, the invention relates to a pressure-sensitive record system comprising a specific colorless chromogenic dye material, Pyridyl Blue, as defined hereinafter, mixed with and adsorbed onto a pigment which is coated onto a dyereceiving sheet along with the usual binder and other paper coating ingredients, and capsules containing an acidic resin dissolved in a suitable solvent, which capsules are coated on the same or an additional sheet.
DESCRIPTION OF THE PRIOR ART
Pressure-sensitive record materials employing colorless chromogenic compounds which form a mark when contacted with an acidic substance are well known in the art. Exemplary thereof are Crystal Violet Lactone (CVL) as described in Reissue patent No. 23,024 and the compouds disclosed in U.S. Pat. Nos. 3,509,173 (3,3-bis (1-ethyl-2-methylindol-3-yl) phthalide, also known as Indolyl Red) and 3,681,390 (2'-anilino-3'-methyl-6'-diethylaminofluoran, also known as N-102 dye).
Japanese application No. 48-29820, published as a Disclosure on Nov. 13, 1974, and Japanese application No. 48-53691, published as a Disclosure on Jan. 20, 1975, both disclose a colorless marking fluid employed in a pressure-sensitive record paper comprising a homolog of Pyridyl Blue and various solvents.
U.S. Pat. No. 3,894,168, which issued on July 8, 1975, discloses a "reverse" system analogous to that employed herein. This prior art, however, does not teach or suggest a reverse system with the use of the Pyridyl Blue dye material as disclosed in the present specification.
SUMMARY OF THE INVENTION
One of the objects of the present invention is to provide a "reverse" pressure-sensitive record system having an improved community of properties as compared with the systems taught in the prior art.
A specific object of the invention is to provide a colorless chromogenic system which imparts improved image strength, print stability (fade resistance) and resistance to degradation in a pressure-sensitive record material.
These and other objects and advantages of the present invention will become apparent to those skilled in the art from a consideration of the following specification and claims.
In accordance with the present invention, Pyridyl Blue, which is a mixture of the isomers 7-(1-ethyl-2-methylindol-3-yl)-7-(4-diethylamino-2-ethoxyphenyl)-5,7-dihydrofuro[3,4-b]pyridin-5-one, and 5-(1-ethyl-2-methylindol-3-yl)-5-(4-diethylamino-2-ethoxyphenyl)-5,7-dihydrofuro[3,4-b]pyridin-7-one, is mixed with and adsorbed onto a pigment such as calcium carbonate and the resulting dye precursor-coated pigment is coated on a dye-receiving sheet together with a suitable binder and the other usual paper coating ingredients. Capsules containing an acidic material, such as a para-phenylphenol-formaldehyde resin or a para-octylphenol-formaldehyde resin, dissolved in a solvent are coated on the same or an additional sheet. Coreaction between the colorless chromogenic dye material and acidic material released from said capsules by means of pressure produces a colored mark.
As noted above, the use of the Pyridyl Blue colorless chromogenic material of the invention imparts improved properties, for example, improved image strength, print stability (fade resistance) and resistance to degradation when compared to systems which employ, for instance, Crystal Violet Lactone in a similar reverse system.
DETAILED DESCRIPTION OF THE INVENTION
Formulations and techniques for the preparation of carbonless copy paper are well known in the art, for example, as disclosed in U.S. Pat. Nos. 3,627,581, 3,775,424 and 3,853,869. However, it is important to note that in the "reverse" system of the invention, the dye (adsorbed onto a pigment) is coated on a dye receptor (CF-coated front) sheet and the acidic resin dissolved in a solvent is enclosed within capsules, whereas the opposite is true in the usual carbonless copy paper transfer system.
The solvent for the acidic resin enclosed within the capsules can be any of those well known in the carbonless copy paper art, e.g.,
dibenzyl ether
Magnaflux oil (saturated hydrocarbon oil, distillation range: 370°-500° F.)
benzyl benzoate
2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TXIB; U.S. Pat. No. 4,027,065)
dibutyl phthalate
1,2,4-trimethyl benzene
ethyldiphenyl methane (U.S. Pat. No. 3,996,405)
C 11 -C 12 alkylbenzene
isopropyl biphenyl (U.S. Pat. No. 3,627,581)
However, the most preferred is a mixed solvent of dibenzyl ether and Magnaflux oil.
Any water-insoluble and approximately chemically neutral pigments such as calcium carbonate, zinc oxide, barium sulfate, titanium oxide, barium carbonate, magnesium carbonate, calcium oxide, magnesium titanate and zinc sulfide can be employed in the present invention. Calcium carbonate is preferred.
In a typical formulation, Pyridyl Blue, a neutral pigment, at least one binder (e.g., a styrene-butadiene latex and/or starch) are admixed in water and coated on a CF sheet. Small amounts of conventional materials such as wetting agents and defoamers can also be employed in the formulation. When used in conjunction with the encapsulated acidic resin, either on the same or a separate sheet, an excellent pressure-sensitive record material is obtained.
The capsules for the acidic resin can be prepared from gelatin as described in U.S. Pat. No. 3,041,289, from a ureaformaldehyde polymer as disclosed in U.S. Pat. No. 4,001,140, from resorcinol-formaldehyde filled poly(vinyl alcohol) wall material capsules as described in U.S. Pat. No. 3,755,190, or from various melamine-formaldehyde polymers as disclosed in U.S. Pat. No. 4,100,103.
EXAMPLES OF THE INVENTION
The following examples are given merely as illustrative of the present invention and are not to be considered as limiting. Unless otherwise noted, the percentages in the examples and throughout the application are by weight.
The test results shown in the Examples were determined in the following manner.
In the Typewriter Intensity (TI) test, a standard pattern is typed on a CF-CB (coated front-coated back) pair. The reflectance of the printed area is a measure of color development on the CF sheet and is reported as the ratio of the reflectance of the printed area to that of the untyped area (I/I o ) and is expressed as a percentage. A high value indicates little color development and a low value indicates good color development. The faded print intensity is measured in the same manner.
Typewriter Intensity tests were also conducted before and after exposure of the print in various ways, including exposure at the noted times to fluorescent light, to natural sunlight, to ambient conditions and within an oven. The fluorescent light test device comprised a light box containing a bank of 18 daylight fluorescent lamps (21 inches long, 13 nominal lamp watts) vertically mounted on 1-inch centers placed 11/2 inches from the sample being exposed. The wall exposure comprised exposure of the print by hanging the printed sheet on the laboratory wall for the noted times, exposed to air, natural and fluorescent room light, and ambient temperature and moisture levels.
The following procedures were used to prepare dye receiving CF sheets containing CVL (Crystal Violet Lactone) and Pyridyl Blue:
EXAMPLE 1
Dye precursor-coated neutral pigment particles
(A) 1 gram of Pyridyl Blue was dissolved in 150 mls of acetone. 70 grams of precipitated CaCO 3 , 20 grams of Cabolite 100 urea-formaldehyde resin pigment (U.S. Pat. No. 3,988,522) and 10 grams of ZnO (Green Seal 8 from New Jersey Zinc Co.) were blended in the above solution and the resulting dispersion was allowed to dry in a hood.
(B) 1 gram of CVL was dissolved in 150 mls of acetone. 70 grams of precipitated CaCO 3 , 20 grams of Cabolite 100 and 10 grams of ZnO (Green Seal 8 from New Jersey Zinc Co.) were blended in the above solution and the resulting dispersion was allowed to dry in a hood.
Paper-coating slurry of dye precursor-coated pigment
The dye precursor-coated pigments (A) and (B) as described above were dispersed individually with the following materials:
__________________________________________________________________________ I II Parts Parts Parts Parts Wet Dry Dry % Wet Dry Dry %__________________________________________________________________________Pyridyl Blue pigment (A) 84 84 83.4CVL pigment (B) 84 84 83.4Penford Gum 260 100 10 9.9 100 10 9.9(modified corn starch)Dow Latex 620 12 6 6.0 12 6 6.0(carboxylated styrene-butadiene latex)Tamol 731 3 0.75 0.7 3 0.75 0.7(25% solution of thesodium salt of apolymeric carboxylicacid, supplied byRohm & Haas)Water 250 -- -- 250 -- --Totals 449 100.75 100.0 449 100.75 100.0__________________________________________________________________________
The above paper-coating slurries were coated on 34 pound bond paper with a No. 12 Mayer rod. After drying, the coating weight was about 4.5 pounds per ream of 500 sheets, measuring 25 by 38 inches.
EXAMPLE 2
Alternate method of manufacture of dye precursor-coated neutral pigment particles and pigment coated sheets
(C) 300 grams of Pyridyl Blue, 600 grams of calcium carbonate, 300 grams of 10% solids Penford Gum 230 (modified corn starch), 1200 grams of water and 30 grams of 25% solids Tamol 731 were attritored for 45 minutes. A few drops of octanol were added, to reduce foaming.
(D) 300 grams of CVL, 300 grams of calcium carbonate, 300 grams of zinc resinate, 300 grams of 10% solids Penford Gum 230, 1200 grams of water and 30 grams of 25% solids Tamol 731 were attritored for 45 minutes. A few drops of octanol were added to reduce foaming.
These attritor grinds were used to formulate dye receiving sheet coating formulas having the following compositions:
______________________________________ III IV Parts Parts Dry Parts Parts Dry Wet Dry % Wet Dry %______________________________________Pyridyl Blue 6.3 2.0 3.0Grind (C)CVL Grind (D) 6.4 2.0 3.0CaCO.sub.3 43.4 43.4 65.8 43.4 43.4 68.8Ansilex Clay 9.9 9.9 15.0 9.9 9.9 15.0(U.S. Pat. 3,586,523)Penford Gum 230 66.0 6.6 10.0 66.0 6.6 10.0Dow Latex 620 8.0 4.0 6.0 8.0 4.0 6.0Calgon T .1 .1 .1 .1 .1 .1(a fused sodium-zincphosphate glasscomposition inpowder form)Water 110.3 -- -- 110.3 -- --Totals 224.0 66.0 99.9 244.0 66.0 99.9Coating Solids 27% 27%Viscosity 58 cps 57 cps______________________________________
These coating slurries were applied to a 34 pound base sheet at a rate of 4.5 lbs. (500 sheets measuring 25 by 38 inches) with an air knife coater.
EXAMPLE 3
Preferred encapsulated acidic marking liquid
The following procedure was used to prepare phenolic resin transfer (CB) sheets to be used in conjunction with the dye receiving (CF) sheets described above:
(E) 1200 grams of para-phenylphenol resin (PPP resin) were dissolved in 3200 grams of dibenzyl ether and 1600 grams of Magnaflux oil. Sufficient heat and agitation were applied to effect solution. 200 grams of EMA 31 (ethylene-maleic anhydride copolymer with a molecular weight range of 75,000 to 90,000) was dissolved in 1800 grams of deionized water with sufficient heat and agitation to effect solution. The prepared EMA solution was diluted with 6000 grams of deionized water and the pH adjusted to 4.0 with 20% sodium hydroxide solution. The oil solution of PPP resin was then emulsified in the EMA water solution with a Cowles Dissolver at 25° C. Emulsification was continued until an average oil drop size of approximately 2 microns was attained. Total drop size distribution ranged from approximately 0.5 microns to 15 microns. The resulting emulsion was then transferred to a water bath controlled at 55° C. and with rapid agitation, 1000 grams of 80% Resloom 714 (etherified methylol melamine) diluted with 1000 grams of deionized water was added. The resulting mix was kept at 55° C. for 2 hours under constant agitation to effect capsule formation. After 2 hours, the temperature was allowed to slowly equilibrate with the ambient temperature. Agitation was continued for an additional 16 hours.
(F) An oil solution of 1400 grams of para-octylphenol resin (POP resin), 3200 grams of dibenzyl ether and 1600 grams of Magnaflux oil was prepared using sufficient heat and agitation to effect solution. This solution was then encapsulated using the procedure described above.
Coating slurries of the above capsules were prepared having the following composition:
______________________________________ V VI Parts Parts Dry Parts Parts Dry Wet Dry % Wet Dry %______________________________________PPP Capsules (E) 26.60 12.50 71.4POP Capsules (F) 27.30 12.50 71.4Stilt Starch 3.20 3.12 17.9 3.20 3.12 17.9Stayco S Starch 6.30 .63 3.6 6.30 .63 3.6Dow Latex 638 2.50 1.25 7.1 2.50 1.25 7.1(carboxylated styrene-butadiene latex)Water 26.40 -- -- 25.20 -- --Totals 65.00 17.50 100.0 65.00 17.50 100.0Coating Solids 27% 27%Viscosity 68 cps 68 cps______________________________________
These coating slurries were applied to a 34 lb. base sheet at a rate of 3.75 lbs. (500 sheets measuring 25 by 38 inches) with an air knife coater. In addition, formulation V was applied to the back side of 34 lb. base sheets having the first side coated with formulations III and IV, respectively, to make CFB (coated front and back) papers.
The CB, CFB and CF papers prepared above were placed in proper imaging sequence and typewriter images were produced thereon. The intensity of these images after print development (24 hours) was determined with an opacimeter. The images were then subjected to various exposures to determine (a) The stability of the imaged print (fade resistance) and (b) The ability of the dye containing receiving (CF) sheet to produce a new print after exposure (CF Decline Resistance), shown below as "New Print Intensity".
The CF sheets prepared in Example 1 produced the following test results:
48 Hour South Window Exposure Test. Imaging done with IBM Memory Typewriter using an "X" character:
______________________________________ Intensity Original After Exposure New PrintCB CF Intensity (Fade) Intensity______________________________________V I 40 41 65VI I 52 53 75V II 40 52 88VI II 56 74 96______________________________________
The CF sheets prepared in Example 2 produced the following test results:
1. 48 Hour Fluorescent Light Box Exposure Test. Imaging done with IBM Executive Typewriter using 4-bar cross hatch character:
______________________________________ Intensity Original After Exposure New PrintCB CF Intensity (Fade) Intensity______________________________________V III 38 48 55V IV 51 74 78V/III CFB 49 51 56V/IV CFB 52 68 75______________________________________
2. 3 week 140° F. oven exposure test. Imaging the same as in Test 1 above:
______________________________________ Intensity Original After Exposure New PrintCB CF Intensity (Fade) Intensity______________________________________V III 40 49 52V IV 48 49 75V/III CFB 48 45 51V/IV CFB 51 51 68______________________________________
3. 9 week wall test (ambient conditions). Imaging done with a solid block character using an IBM Selectric typewriter:
______________________________________ Intensity Original After Exposure New PrintCB CF Intensity (Fade) Intensity______________________________________V III 32 42 44V IV 34 54 76V/III CFB 33 42 45V/IV CFB 35 55 76______________________________________
4. 7 week wall test (ambient conditions). Imaging done as in Test 3 above
______________________________________ Intensity Original After Exposure New PrintCB CF Intensity (Fade) Intensity______________________________________V III 33 38 48VI III 44 56 54V IV 34 45 72VI IV 57 73 89______________________________________
Therefore, when used as described herein and when compared with Crystal Violet Lactone at the same concentration, Pyridyl Blue shows the following characteristics:
Equivalent image strength with respect to CVL when imaged with PPP Resin solution.
Superior image strength with respect to CVL when imaged with POP Resin solution.
Superior print stability (fade resistance) with respect to CVL under all exposed tests.
Superior resistance to degradation (CF decline) with respect to CVL under all exposure tests.
In a typical procedure the Pyridyl Blue employed in the above examples is prepared in the following manner. A quantity of 58.0 g (0.188 mole) of (1-ethyl-2-methylindol-3-yl) (3-carboxypyridin-2-yl)ketone and its isomer is stirred for 2 hours at 60°-65° C. with 35.3 g (0.188 mole) of N,N-diethyl-m-phenetidine and 250 ml of acetic anhydride. The reaction mixture is poured into 500 ml of water and the acetic anhydride hydrolyzed by slowly adding 450 ml of 29% ammonium hydroxide. After stirring for 2 hours, the resulting solid is filtered. It is washed with water, 200 ml of 40% methanol/water and 50 ml of petroleum ether (b.p. 60°-110° C.). The solid is dried in a 75° C. oven to a constant weight of 80.5 g (90%) of the desired product, Pyridyl Blue, mp 134°-137° C.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications are intended to be included within the scope of the following claims. | A pressure-sensitive record material comprising the colorless chromogenic dye Pyridyl Blue mixed with and adsorbed onto a pigment which is coated on a substrate sheet, and capsules containing an acidic resin dissolved in a suitable solvent, the capsules being coated on the same or an additional sheet. This "reverse" system (where the acidic resin rather than the dye is encapsulated) provides an improved community of properties, including improved image strength, print stability (fade resistance) and resistance to degradation. Pyridyl Blue is a mixture of the isomers 7-(1-ethyl-2-methylindol-3-yl)-7-(4-diethylamino-2-ethoxyphenyl)-5,7-dihydrofuro[3,4-b]pyridin-5-one and 5-(1-ethyl-2-methylindol-3-yl)-5-(4-diethylamino-2-ethoxyphenyl)-5,7-dihydrofuro[3,4-b]pyridin-7-one. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates generally to medical instruments. More particularly, it relates to external pressure applicators and methods for administering eyedrop medicine. The lacrimal canaliculi (also known as tear ducts) allow tears to flow from the eye surface into the lacrimal sac and subsequently into the nasolacrimal ducts and exit through the nose into the back of the throat. The distal part of the nasolacrimal ducts are encased in bone and pressure on the skin external to that part will not impede tear drainage. Applying small pressure on the skin over any other part of the tear drainage path can effectively block tear drainage into the rest of the system. When administering eyedrop medicine on the eye, blocking this drainage path (also known as punctal occlusion) for a few minutes will enable the eye to fully absorb the medicine.
The current method of administering short-term punctal occlusion is to have the patient use a finger to press down upon the skin overlying the lacrimal canaliculi, lacrimal sac, and/or superior portion of the nasolacrimal ducts. Ophthalmologists typically prescribe 5 minutes of pressing time per eyedrop application. For example, when glaucoma patients are treated with multiple types of eyedrops, a 5 minute pressing time for each type of eyedrop would add up to a long duration of 15-20 minutes. Holding the finger for such a long duration is uncomfortable and not practical for most people. Consequently, patients seldom follow this practice as prescribed, thereby decreasing the efficacy of the treatment. Another issue is that patients seldom know exactly where the correct pressing point is located. Pressing on an incorrect area will not close the tear drainage path and therefore will not stop the eyedrop flow into the rest of tear drainage system. As a result, the retention time of eyedrop on the eye and effectiveness of the medicine is sub-optimal. This problem limits optimal treatment response leading to unnecessary prescription of additional medications, worsening disease, and risks of expensive eye surgery.
Punctal Occlusion plugs are disclosed in U.S. Pat. Nos. 6,994,684, 6,290,684, 5,830,171, 5,723,005, 5,334,137, and 5,283,063. However, all these patents involve some invasive procedures that may not be administered by patients alone. The subject matter of noninvasive external punctal occlusion is disclosed in the following patents:
U.S. Pat. No. 5,515,872 to Martin et al. discloses a clamp for placing over the nose bridge prior to ocular medication, to seal the nasolacrimal sac to prevent drainage of medication away from the eye. The clamp is positioned by a flexible molded nose cover. In one embodiment, the clamp is attached to eyeglasses designed to accept eyedrop applied to the eye. Subsequently, U.S. Pat. No. 5,832,930 was filed that added modified eyeglass frame and elastic fastening bands.
U.S. Pat. No. 5,522,837 to Latina discloses a U-shape device, with a bulbous element on the end of each leg that performs the similar function as the nose clamp except it requires hand positioning and pushing. The said device also has a pair of tubes attached to it to channel the eyedrop onto the eyes.
The nose clamp has its limitation as it may be difficult to clamp on a shallow or flat nose bridge. Positioning the pressure point right on the tear drainage path is the key to effective punctal occlusion. The flexible molded positioning device associated with the nose clamp may have difficulty to fit on the exact location on the nose as the nose boundary is somewhat fuzzy. The U-shape pressing device depends on patients to put the device on the right spot. The Martin clamp and Latina U-shape device would in no way suggest the device of this invention because they compress the nasolacrimal sac or nasolacrimal ducts on the nose rather than lacrimal canaliculi on the orbital rims.
To assure the punctal occlusion device functioning properly, a method is needed to calibrate the occlusion pressure and to verify the occlusion effectiveness. None of the prior patents disclose such method. Furthermore, it is desirable to enable patients to resume normal life activities while using the device such as wearing glasses or driving a car. None of the prior devices offer such capability.
In addition to the said punctal occlusion, there is a need to assure that the eyedrop goes into the eye. The methods and devices disclosed in the prior patents rely on passive devices to guide the eyedrop and the passive devices may come in contact with the eyedrop. A better way to guide the eyedrop is to enable the patients to see the position of the eyedrop bottle and thereby to actively aim the tip of the eyedrop bottle at the eyes.
The herein disclosed invention overcomes all the above limitations of prior devices
BRIEF SUMMARY OF THE INVENTION
The device of this invention provides hands-free, noninvasive short-term punctal occlusion, during the eyedrop administration for the purpose of prolonging medicine retention time on eyes. While wearing this device, patients are able to continue performing other activities, such as concurrently wearing a pair of eyeglasses and even driving a car which will likely increase patient's compliance with their eyedrop regimen. The path that allows tears to drain away from eyes includes the lacrimal canaliculi, lacrimal sac, and nasolacrimal duct. Applying small pressure on any of these segments, except the distal part of nasolacrimal duct, can block the tear drainage. However, it is difficulty to locate these segments as they are deeply positioned under the skin.
The device of this invention specifically blocks the lacrimal canaliculi next to the eye, unlike the prior devices that attempt to block the nasolacrimal sac or nasolacrimal ducts on the nose. As one of the important claims of this invention, the said device leverages the unique shape of the nasal aspect of the orbital rim to position the lacrimal canaliculi that lay across the orbital rim. This said orbital rim section is narrow and curved which enables the said device to fit into it precisely. The said device is adjustable to accommodate differences in nose width and contour of the said orbital rim. Beside the self-positioning capability, blocking the lacrimal canaliculi is far superior than blocking other down stream path as it enables maximum possible retention of medicine within the eyes.
The said device can not only be utilized prior to administering each eyedrop medicine to block fluid from draining away from the eye to prolong the eyedrop medicine retention time but also be used for administering multiple consecutive eyedrop medicine, provided that each eyedrop application is spaced out in 5 minute interval, or as prescribed by Ophthalmologist, and the residual medicine in the eye is wiped out by tissue, or other absorbent, prior to applying the next eyedrop.
Certain eyedrop medicines have a bitter taste. This bitter taste allows the patient to detect if the eyedrop medicine is leaking through the nose into the back of the throat. An effective punctal occlusion device should stop this leak. For non-invasive external punctal occlusion, the pressure required to close the lacrimal canaliculi is very small, the patient may preset this pressure for optimal treatment as too little pressure would not close the lacrimal canaliculi and too much pressure is unnecessary and uncomfortable. A procedure to determine the optimal pressure is to escalate the pressure exerted to the lacrimal canaliculi in each eyedrop application until the leaking taste stops. The device of this invention allows patients to experimentally set this optimal pressure. For patients using tasteless eyedrop, some eyedrop with color dye may be administered and leak be verified by an Ophthalmologist.
The device of this invention consists of a continuous iron wire frame, may be coated with plastic or other rust proofing materials, with a V-shape central segment, a pair of curved segments, frontal segments, temple segments and hook and loop fastening bands (Velcro®). The curved segment of this said device comprises the said iron wire core covered with a soft rubber tube that can be bended in a shape to fit the nasal aspect of the orbital rim to enable application of firm pressure on the lacrimal canaliculi for the purpose of performing punctal occlusion during administration of certain eyedrop medicines that require prolonged retention time. The said V-shape central segment of this device is for joining the said pair of curved segments together and the adjustable V-shape angle is for adjusting the distance between the said pair of curved segments so that the said curved segments can fit the orbital rims on each sides of the nose. The said frontal segments of this said device are to wrap around the forehead and extend into temple segments and then fastening bands. The shape of the said frontal segments can be in many different forms as long as it clears the forehead which is about 1 inch radius distance from the most concaved spot of the said curved segments. The said temples should have a length to reach the ears and have an outward angle from the frontal segments. This outward angle is to provide sufficient tension on fastening bands. This said tension is transmitted through the said device frame to become occlusion pressure on lacrimal canaliculi when the bands are fastened on the back of the head.
The device of this invention is able to position itself on top of the lacrimal canaliculi via fitting the said pair of curved segments onto the nasal aspect of the orbital rims. The occlusion pressure applied on the lacrimal canaliculi by the device of this invention is adjustable via varying the temple segment outward angles and/or fastening band length. Furthermore, this device enables hands-free operations and concurrent wearing of eyeglasses.
The device of this invention further includes a visual reference attachment that provides visual referencing points for positioning the tip of an eyedrop bottle towards the eyes. Instead of passively channeling the eyedrop towards the eyes, the said attachment enables the patient to see the exact position of their eyedrop bottle and thereby be able to actively aim the tip of the eyedrop bottle towards the eyes. This said attachment can be detached from the said device for patients who do not have problem to aim their eyedrop towards the eyes.
The current invention has many advantages over prior devices that perform similar functions:
1. The disadvantage of prior devices of pressing on nasolacrimal ducts is that the distal part of nasolacrimal ducts is encased in bone and incompressible. The superior part of the nasolacrimal ducts is outside the bone and compressible but is invisible and the exact location of this portion is uncertain to patients. Furthermore, clamping on the nose tends to slip away from the nose due to the angle shape of the nose bridge, especially for people with a very shallow or flat nose bridge.
2. The device of this device performs punctal occlusion via compressing lacrimal canaliculi on the nasal aspect of the orbital rim without any chance of misplacement. It follows the well defined contour of the nasal aspect of the orbital rims to positively fit across the lacrimal canaliculi and does not need additional positioning device.
3. The device of this invention allows adjustments to fit individual's orbital rim curvature and nose width.
4. The device of this invention enables patients to customize the lacrimal canalicular occlusion pressure via varying temple outward angle and altering fastening band length as disclosed in claim 3 . The optimal occlusion pressure is determined based on a leak test method as disclosed in claim 7 . The other spring based clamping device offers a few spring strength selections and does not disclose any leak test method. The hand pushed device has no pressure setting but the feel of patient's hand. Therefore, the device of this invention is far more effective in delivering the optimal punctal occlusion pressure.
5. The device of this invention can be worn concurrently with a pair of eyeglasses, none of other devices can.
6. The device of this invention, when used with a visual reference attachment, enables patients to aim the tip of the eyedrop bottle towards their eyes, none of other devices can.
The device of this invention utilizes a one wire frame construction that is easy to build, adjust, and inexpensive to commercialize. A successful commercialization of this device will revolutionize eyedrop medication procedure, reduce eye medication cost, avoid high cost on eye surgery, and eventually lower the health care costs in our society.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 is the device of this invention that fits the nasal aspect of the orbital rim.
FIG. 2 is the anatomy of tear drainage path.
FIG. 3 is the anatomy of tear drainage path overlaid with the curved segment of the device of this invention.
FIG. 4 is the front view of the device of this invention.
FIG. 5 is the side view of the device of this invention.
FIG. 6 is the top view of the device of this invention.
FIG. 7 is the front view of a patient wearing the device of this invention and a pair of eyeglasses.
FIG. 8 is the side view of a patient wearing the device of this invention and a pair of eyeglasses.
FIG. 9 is the front view of the device of this invention with a visual reference attachment.
FIG. 10 is the side view of a patient wearing the device of this invention with a visual reference attachment.
DETAILED DESCRIPTION OF THE INVENTION
The basic embodiment of this invention is a device that enables patients to perform noninvasive punctal occlusion to prolong eyedrop retention time on eyes. The path that allows tear to drain away from eyes includes lacrimal canaliculi, lacrimal sac, and nasolacrimal ducts. Applying pressure on skin above any one of these segments, except the distal part of nasolacrimal ducts, can block the tear drainage path. The distal part of nasolacrimal ducts are encased in bone and can not be blocked by pressure on the skin over this part of nasolacrimal ducts. Applying pressure on superior part of nasolacrimal ducts by a clamp may risk the possibility of miss-placing the clamp on the bone as there is no distinguishable feature on the nose to signify where the nasolacrimal ducts begin entering the bone. For this reason, the device of this invention applies pressure on lacrimal canaliculi instead which is clearly identifiable by following the nasal aspect of the orbital rim that concaves in a narrow space next to the eye. This unique contour of the said orbital rim enables the curved segments of the device of this invention to fit onto the said orbital rim seamlessly where the lacrimal canaliculi lay across underneath. The device of this invention is further adjustable to fit different distances between two orbital rims across the nose bridge.
Referring now to FIG. 1 , the device of this invention is fitted onto the nasal aspect of an orbital rim 3 . The said device has a pair of curved segments 1 that can be adjusted to fit the contour of the said orbital rim 3 . Each curved segment 1 is an iron core, as shown in dotted line, and is sleeved with a soft rubber tube 2 . The device of this invention can be worn as eyeglasses except its temples 6 are fastened with a pair of hook and loop bands (Velcro®) around the back of the head.
Referring now to FIG. 2 , it shows the tear drainage path from lacrimal canaliculi 7 through lacrimal sac 8 to nasolacrimal ducts 9 and out of the nose. It also shows the nasal aspect of the orbital rim 3 , which the device of this invention is based upon to locate the lacrimal canaliculi 7 . The distal part of the nasolacrimal ducts are encased in bone and pressure on the skin will not affect the structures inside the bone. Furthermore, there is no distinguishable surface feature to signify where the compressible section of nasolacrimal ducts begins. The lacrimal canaliculi 7 are located next to the eye crossing the said orbital rim 3 and only a few millimeters under the skin surface. The unique shape and location of the said orbital rim enable the device of this invention to unmistakably fit onto lacrimal canaliculi.
Referring now to FIG. 3 , it shows the anatomy of the tear drainage path overlaid with the curved segment 1 of the device of this invention. The said curved segment 1 , covered with a soft rubber tube 2 , is fit into the narrow space between the eye and nose and is bended concaved downward to meet the entire contour of the orbital rim 3 in that space. The rubber tube 2 is long enough to cover the entire skin contact area for wearing comfort and for assurance of crossing the lacrimal canaliculi 7 lay underneath. Through this said rubber tube 2 , small pressure can be applied on the skin to effectively block the tear drainage into the rest of the system. When administering certain eyedrop medicine on the eye, blocking this drainage path for a few minutes will enable the eye to fully absorb the medicine.
Referring now to FIG. 4 , it shows the front view of the device of this invention. The said device is made out of a single continuous piece of iron wire. The wire should be soft enough to be bendable without using special tools yet strong enough to fix the structure shape while wearing the said device. The wire may be plastic coated or covered with other rust proofing materials. A pair of curved segments 1 of the said device is sleeved with soft rubber tubes 2 . The said curved segments 1 are joined together by a V-shape central segment 5 . The other ends of the curved segments 1 are extended forward and side way into a pair of frontal segments 4 and then angled backwards to form a pair of temples 6 . At the end of each temple 6 , the iron wire is bended to form a hook 10 for attaching hook and loop fastening band (Velcro®) 11 .
Referring now to FIG. 5 , it shows the side view of the device of this invention. The curved segment 1 , shown as core in dotted line, is covered by the soft rubber tube 2 . The curvature of the said curved segment 1 along with rubber tube 2 can be adjusted together by applying forces in the directions as illustrated by the two-way arrows 12 , to compress or expand the space between the frontal segment 4 and V-shape central segment 5 .
Referring now to FIG. 6 , it shows the top view of the device of this invention. The tip of the V-shape central segment 5 is approximately lined up with the frontal segments 4 of the said device. The shape of the said frontal segments 4 can be in many different forms as long as it clear the forehead which is about 1 inch radius distance 14 from the most concaved spot of the said curved segments 1 . The angle 15 between the V-shape central segments 5 can be widened or narrowed by applying forces in the directions indicated by two-way arrows 16 so that the curved segments 1 will fit two orbital rims across the nose. The total width of the frontal segments 4 should be similar to the frame of normal eyeglasses and the temple segments 6 should be long enough to reach the ears. The angle 17 between the frontal segment 4 and temple segment 6 should be kept in sufficient outward direction in order to provide adequate tension on the fastening bands 11 when two fastening bands 11 are attached to each other behind the head. While wearing this device, the backward pressure exerted by the head onto the fastening bands 11 will be transmitted via the device frame to become the compression pressure on the lacrimal canaliculi. This compression pressure is adjustable by varying the angle 17 and/or the length of fastening bands 11 . The marks 13 on the fastening band 11 are to record the preferred band length for preferred pressure. The angle 17 can be adjusted by applying forces in the directions indicated by two-way arrows 18 .
Referring now to FIG. 7 , it shows the front view of a patient wearing the device of this invention and a pair of eyeglasses 19 . The patient wears the device first and then wears the eyeglasses on top of it. The nose pads 20 of the eyeglasses seats on the nose bridge above the rubber tube 2 covered curved segments 1 . The frontal segments 4 are above the eyeglass 19 frame. This front view shows wearing this said device will not interfere with wearing eyeglasses.
Referring now to FIG. 8 , it shows the side view of a patient wearing the device of this invention and a pair of eyeglass 19 . The side view clearly shows the rubber tube 2 covered curved segment 1 , is clearly behind the nose pad 20 and the frontal segment 4 is above the eyeglass 19 frame. This side view also shows wearing this said device will not interfere with wearing of eyeglasses.
Referring now to FIG. 9 , it shows an optional embodiment that a U-shape visual reference attachment 21 is attached to the temple segments 6 of the device of this invention via a pair of clip-on hooks 23 at the ends of the U-shape frame. The front part of the said attachment has a pair of pointers 22 that provide the reference points for aiming the tip of the eyedrop bottle towards the eyes. These said pointers may slide sideway to adjust for eye positions. This said attachment 21 and pointers 22 may be made of rigid metal or plastic material.
Referring now to FIG. 10 , it shows the side view of a patient wearing the device of this invention with the said visual reference attachment 21 attached. The upper surface of the eyedrop bottle 24 is lined up with the reference pointer 22 via a projection line 25 . | A device enables a patient to perform non-invasive punctal occlusion by applying firm pressure to the skin external to the lacrimal canaliculi during the administration of eyedrop medicine, for the purpose of prolonging the medicine retention time. The device of this invention may be adjusted to fit the nasal aspect of the orbital rims where the lacrimal canaliculi are located. The pressure to be applied on the lacrimal canaliculi is adjustable to meet the optimal pressure requirement. The device also has a visual reference attachment that provides visual referencing points for positioning the tip of the eyedrop bottle towards the eyes. This device enables a hands-free operation and does not interfere with the wearing of eyeglasses. | 0 |
FIELD OF THE INVENTION
The invention is in the field of fluid reclamation systems. More particularly, the invention is a system for recycling the liquid coolant used in an internal combustion engine. The system treats the used coolant, typically known as antifreeze, by first removing any non-desired impurities entrained in the liquid. New materials are then added to the liquid so that it regains the characteristics of unused antifreeze.
BACKGROUND OF THE INVENTION
Most internal combustion engines make use of a circulating liquid to partially remove the heat generated by the combustion process. This liquid is predominantly water that is mixed with glycol-based and/or alcohol-based materials and assorted other compounds. The alcohol and/or glycol-based materials primarily function to raise the water's boiling point and to lower its freezing point. The other added compounds perform ancillary functions such as stabilizing the mixture, inhibiting corrosion and making the fluid easily discernable from water.
A typical antifreeze/water mixture designed for use in an internal combustion engine makes use of an approximately 50--50 mixture of ethylene glycol and water. The resultant mixture will have a boiling point of approximately 235 degrees Fahrenheit and a freezing point of approximately minus 35 degrees Fahrenheit.
The freezing and boiling point temperatures listed in the above example are typical for a relatively unused, freshly mixed quantity of coolant fluid. However, the characteristics of the liquid change significantly over time and with usage in the engine. The alcohols/glycols break down and are converted into related acids such as glycolic acid, oxalic acid and formic acid. This causes a lowering of the fluid's boiling point and a raising of its freezing point. In addition, the acids created by the breakdown of the glycols/alcohols change the ph level of the coolant from approximately 10 (for fresh coolant) down to approximately 7 for old, used coolant.
As the ph level of the coolant decreases, the coolant becomes increasingly corrosive to the exposed metal parts of the engine. Over time, the metal parts become weakened and begin to disintegrate. Also over time, particles of dirt, salt, metal oxides and other metallic and non-metallic particles become entrained or dissolved in the coolant fluid. As an added consequence, some of the particles in the fluid settle on or adhere to the exposed metal surfaces of the engine and effectively reduce the cooling efficiency of the system. In addition, these particles tend to clog small passages in the engine and radiator and thereby cause reduced cooling capacity and create hot spots in the engine. These particles can also build up in the water pump and cause it to fail.
To avoid the above noted problems, replacement of a vehicle's coolant is a routine maintenance procedure that is performed at regular intervals. The old coolant is drained from the engine and replaced with new, fresh coolant. The old coolant is then either disposed of or recycled.
Used engine coolant normally cannot be disposed of by pouring it into a municipality's sewage system. The coolant is toxic and contains dissolved or entrained metals that are not easily broken down. In addition, the glycol and/or alcohol components remaining in solution are still usable and are valuable materials. For these reasons, a concerted effort is being made to recycle the large quantities of used engine coolant that are removed during vehicle maintenance.
The recycling of used engine coolant is normally a complex and expensive process. Miller (U.S. Pat. No. 4,946,595) teaches a typical system for recycling used coolant. He shows a sophisticated apparatus that employs multiple filters and a central tank. A high pressure pump is employed as well as a plurality of valves to control the liquid flow.
All of the recycling equipment presently used for antifreeze is similar to Miller in that the equipment is complex, requires a significant of space, and is extremely expensive to acquire and to operate. It is economically unfeasible for a typical vehicle servicing facility to own such equipment. As a result, antifreeze collected by these facilities is often disposed of and is not recycled. In some cases, the used antifreeze is collected over time until it can be transported to a recycling plant that specializes in the recycling of such fluids. In this latter situation, recycling of the used coolant is extremely inconvenient and is still expensive.
SUMMARY OF THE INVENTION
The invention is a system for recycling engine coolant and other fluids. The system makes use of a moderately-sized tank and is designed to process relatively small amounts of used coolant over along period of time.
The tank is preferably fabricated from a standard fifty-five gallon steel drum. Located at opposite ends of the top of the tank are two vertically-oriented standpipes. Each standpipe is fabricated from a length of large diameter pipe and is open at the bottom to the interior of the tank.
The first of the two standpipes is the input standpipe and is used for inputting used antifreeze into the tank. This standpipe has a lower portion that extends into the tank to a point near the tank's bottom surface. The top of the standpipe is fully open to facilitate the entry of the coolant. Located a short distance below the top of the standpipe is a scum clean-out port that is preferably controlled using a standard-type valve.
The second standpipe is the outlet standpipe through which the coolant product is outputted from the tank. The bottom of this standpipe is flush with the tank's top surface and is in fluid communication with the interior of the tank. The standpipe includes a small vent at the top and an outlet port located a few inches below the vent. The outlet port preferably directs the fluid to a de-ionizing cartridge or other type of filtering/treatment cartridge that accomplishes the final finishing step of the liquid purifying portion of the system.
Used coolant normally is a mixture of floating material, clear liquid and heavy particles. The system is designed to isolate the clear liquid and remove from it any undesirable materials. To accomplish this, the used coolant will normally have a residence period of one to two weeks within the tank before the clean liquid passes through the outlet port in the second standpipe. There are typically three purification stages that the coolant passes through before the clean liquid is dispensed from the system.
The first stage occurs when the coolant is entered into the input standpipe. Any floatable material in the coolant rises to the top liquid level in the standpipe and is captured therein. The liquid coolant eventually passes through the bottom of the standpipe and enters the large volume of liquid located in the interior of the tank.
Once the liquid leaves the first standpipe, the second purification stage begins. Over time, the coolant mixes with the coolant already in the tank and heavy materials come out of solution and settle to the bottom of the tank. Gravity also acts on the liquid coolant in the tank to separate the liquid into layers, with the purest, least-dense fluid becoming located at the top of the tank.
In the third purification stage, the topmost layer of liquid is drawn from the top of the tank into the bottom opening of the second standpipe. The lightest of this liquid travels upwardly in the standpipe and is directed to the outlet port where it then proceeds into the filter cartridge for the last stage of purification. It should be noted that in some instances, when the liquid that exits from the outlet port is sufficiently clean to require no further purification, the filter cartridge is not employed.
When a user enters used coolant into the input standpipe, the weight of the liquid causes an equal volume of relatively clean liquid to be dispelled from the outlet standpipe. It should be noted that the outputted material causes a siphon effect that is broken only once the fluid level in the output standpipe falls to a point where air entering from the vent reaches the output port.
The basic system can be modified in a number of ways. For example, to speed up the process, oxidants can be mixed with the used coolant as it is entered into the first standpipe. In another variation of the process, anion and cation resins may be placed within the tank for the deionization of the inputted coolant.
Once the cleaned coolant leaves the tank, materials are normally added to the fluid so that its characteristics match those of unused antifreeze. The added materials would usually include anti-corrosion substances, new glycol and/or alcohol components, dyes, and stabilizers. This last step can be completed by the personnel of a vehicle repair facility using relatively inexpensive instruments.
The system does not require a pump or sophisticated screens and filters. The system relies primarily on the natural sedimentation and clarification processes that act on a fluid over an extended period of time. The system takes up little space, is low in cost and is easy to operate. This allows the system to be utilized by and located at a typical vehicle servicing facility.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of an antifreeze recycling system in accordance with the invention.
FIG. 2 is a schematic representation of a second embodiment of an antifreeze recycling system in accordance with the invention.
FIG. 3 is a schematic representation of a third embodiment of an antifreeze recycling system in accordance with the invention.
FIG. 4 is a schematic representation of a fourth embodiment of an antifreeze recycling system in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings in greater detail, wherein like reference characters refer to like parts throughout the several figures, there is shown by the numeral 1 the processing unit that forms the main part of an antifreeze recycling system in accordance with the invention.
The unit includes a drum-shaped settling tank 2 that has a first standpipe 4 and a second standpipe 6. The tank 2 is preferably fabricated from a standard fifty-five gallon steel drum (having typical dimensions of approximately two feet high by three feet in diameter) that is placed on end as shown. Alternately, the tank can be oriented on its side with its longitudinal axis lying in a horizontal plane and the two standpipes extending upwardly from what used to be the side of the tank.
The first standpipe 4 is the input standpipe and is open at its top and bottom ends. The standpipe preferably has a large diameter portion 10 located above the tank and a smaller diameter portion 12 that extends downwardly into the tank and ends near the tank's bottom surface 14. The large diameter of the top portion provides an increased area to trap floating matter. Located in the top portion of the standpipe is a clean-out port 16 that extends to a valve 17. The clean-out port allows a user to drain from the standpipe any fluid or floating matter that is located above the port.
The second standpipe 6 is the output standpipe and is open to the top-most part of the interior of the tank at its bottom end 18. Standpipe 6 is preferably of the same diameter as the top portion 10 of the input standpipe. Located at the top of the standpipe is a vent 20 that is open to the ambient environment. Located below the top of the standpipe is an outlet port 22. The port extends into pipe 24 which is preferably connected to a finishing cartridge 26. A valve 28 is located in the piping to allow manual control of the flow of liquid in the pipe. The cartridge 26 is used to remove any remaining dissolved minerals and metals from the liquid and preferably includes anion and cation resins.
The method of operation of the unit will now be described. The arrows in FIG. 1 show the progress of liquid through the apparatus.
The unit will normally be filled with used antifreeze that is in the process of becoming cleaned. The liquid levels in the standpipes will be as shown in FIG. 1. A quantity of used antifreeze, typically one to two gallons, is poured into the open top 30 of the input standpipe 4. Within the standpipe 4, the first stage of the reclamation process occurs.
The newly entered antifreeze mixes with the liquid already in the standpipe and tends to slowly settle toward the bottom. Any floatable material entrained in the liquid rises within the standpipe and collects at the top of the standpipe. This floating material is drained at a later time via the clean-out port 16. At the same time, any heavy particles fall directly downwards where they exit from the bottom of the standpipe and collect at the bottom of the tank. The bulk of the newly entered used antifreeze eventually exits from the bottom of the standpipe and mixes with the used antifreeze in the interior of the tank. At this point, the second stage of the reclamation process begins.
As the used antifreeze mixes with the antifreeze already in the unit, entrained particles continue to fall out of suspension and settle to the bottom of the unit. Over a long period of time, a degree of oxidation takes place and the dissolved metals become oxidized and settle with the other particles and salts at the bottom of the unit.
Gravity causes the liquid in the tank to separate into layers of varying densities with the top layer being the lightest and containing almost no impurities. The lowest density liquid also fills the output standpipe 6. Whenever new liquid is added to the unit via the input standpipe 4, manometric action causes additional liquid in the top layer within the tank to move into the output standpipe. The addition of new liquid also causes the relatively clean liquid within the standpipe to be outputted via the outlet port 22 and to pass into piping 24. The liquid is then preferably directed to cartridge 26 for final treatment. The liquid exits from the cartridge (or piping 24 if a finishing cartridge is not employed) and is then captured in a container (not shown). The third purification stage encompasses the collection of the liquid into the output standpipe and also any finishing processes the liquid might undergo before exiting from the apparatus.
The container of clean liquid is then mixed with anti-corrosion materials, dyes, stabilizers (if necessary) and additional glycol-based and/or alcohol-based components to return it to its original, like-new condition. The liquid antifreeze is then ready for reuse.
As an alternate to the process described above, the reclamation process can be modified by the addition of oxidizing agents with the inputted used antifreeze. The agents act to facilitate the precipitation of dissolved materials and neutralize the acids.
FIG. 2 shows a second embodiment of the invention. In this embodiment, the basic structure of the unit 1' is unchanged. However, a cloth filter bag 40 is tightly secured to the bottom of the input standpipe 4' using a circular fastener 42. Within the cloth bag is an anion resin bed 44 and a cation resin bed 46 that together function to remove dissolved metals and minerals from the liquid. The inputted used antifreeze must pass through these two beds of materials before mixing with the used antifreeze already within the main body of the tank 2. In this embodiment, the finishing cartridge 26' is optional. If used, the cartridge may contain other deionizing chemicals or a fine filter.
FIG. 3 shows a third embodiment of the invention. This embodiment is similar to the second embodiment except that a filter bag 50 extends into the main body of the tank 2" and floats in the liquid. Located within the bag is a mixed bed 52 of anion and cation resins that function to remove dissolved metals and minerals from the liquid as it passes through the bag before mixing with the liquid in the main body of the tank 2". In this embodiment, the finishing cartridge 26" is optional. If used, the cartridge may contain other deionizing chemicals or a fine filter.
FIG. 4 shows a fourth embodiment of the invention. In this embodiment, a mixture of anion and cation resins is poured through the input standpipe 4"' and settles at the bottom of the tank 2"'. This forms a mixed bed 60 of anion and cation resins that completely covers the bottom opening of the standpipe 4"'. As in the previously described embodiments, the used antifreeze must pass through the resin bed before mixing with the antifreeze contained in the main body of the tank 2"'. In this embodiment, the finishing cartridge 26"' is optional. If used, the cartridge may contain other deionizing chemicals or a fine filter.
It should be noted that the apparatus of the invention can also be used to remove impurities from liquids other than antifreeze. The basic concept used of clarifying the inputted liquid by gravity settling of the impurities is applicable to most liquids however, the required residence time within the apparatus would be proportional to the viscosity of the liquid.
The embodiments disclosed herein have been discussed for the purpose of familiarizing the reader with the novel aspects of the invention. Although preferred embodiments of the invention have been shown and described, many changes, modifications and substitutions may be made by one having ordinary skill in the art without necessarily departing from the spirit and scope of the invention as described in the following claims. | The invention is an antifreeze reclamation system that is designed for low volume processing over extended time periods. The system makes use of a tank that is preferably fabricated from a standard fifty-five gallon drum. Attached to the top of one end of the tank is a standpipe used for inputting used antifreeze into the system. A second standpipe is located at the top of the opposite end of the tank. The system functions by allowing gravity, buoyancy and time to separate the used antifreeze from entrained and dissolved impurities. The outputted liquid is mixed with new materials to restore it to its original, unused condition. | 1 |
RELATED APPLICATIONS
[0001] This application is a continuation of copending U.S. application Ser. No. 10/789,357, which was filed on Feb. 27, 2004, which is a continuation of U.S. application Ser. No. 09/693,548, which was filed on Oct. 19, 2000, now U.S. Pat. No. 6,712,486, which claims the benefit of U.S. Provisional Patent Application Nos. 60/160,480, which was filed on Oct. 19, 1999 and 60/200,351, which was filed on Apr. 27, 2000. The entirety of each of these related applications is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention is in the field of light emitting diode (LED) lighting devices and more particularly in the field of an LED lighting module having heat transfer properties that improve the efficiency and performance of LEDs.
[0004] 2. Description of the Related Art
[0005] Light emitting diodes (LEDs) are currently used for a variety of applications. The compactness, efficiency and long life of LEDs is particularly desirable and makes LEDs well suited for many applications. However, a limitation of LEDs is that they typically cannot maintain a long-term brightness that is acceptable for middle to large-scale illumination applications. Instead, more traditional incandescent or gas-filled light bulbs are often used.
[0006] An increase of the electrical current supplied to an LED generally increases the brightness of the light emitted by the LED. However, increased current also increases the junction temperature of the LED. Increased juncture temperature may reduce the efficiency and the lifetime of the LED. For example, it has been noted that for every 10° C. increase in temperature, silicone and gallium arsenide lifetime drops by a factor of 2.5-3. LEDs are often constructed of semiconductor materials that share many similar properties with silicone and gallium arsenide.
SUMMARY OF THE INVENTION
[0007] Accordingly, there is a need in the art for an LED lighting apparatus having heat removal properties that allow an LED on the apparatus to operate at relatively high current levels without increasing the juncture temperature of the LED beyond desired levels.
[0008] In accordance with an aspect of the present invention, an LED module is provided for mounting on a heat conducting surface that is substantially larger than the module. The module comprises a plurality of LED packages and a circuit board. Each LED package has an LED and at least one lead. The circuit board comprises a thin dielectric sheet and a plurality of electrically-conductive contacts on a first side of the dielectric sheet. Each of the contacts is configured to mount a lead of an LED package such that the LEDs are connected in series. A heat conductive plate is disposed on a second side of the dielectric sheet. The plate has a first side which is in thermal communication with the contacts through the dielectric sheet. The first side of the plate has a surface area substantially larger than a contact area between the contacts and the dielectric sheet. The plate has a second side adapted to provide thermal contact with the heat conducting surface. In this manner, heat is transferred from the module to the heat conducting surface.
[0009] In accordance with another aspect of the present invention, a modular lighting apparatus is provided for conducting heat away from a light source of the apparatus. The apparatus comprises a plurality of LEDs and a circuit board. The circuit board has a main body and a plurality of electrically conductive contacts. Each of the LEDs electrically communicates with at least one of the contacts in a manner so that the LEDs are configured in a series array. Each of the LEDs electrically communicates with corresponding contacts at an attachment area defined on each contact. An overall surface of the contact is substantially larger than the attachment area. The plurality of contacts are arranged adjacent a first side of the main body and are in thermal communication with the first side of the main body. The main body electrically insulates the plurality of contacts relative to one another.
[0010] For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention have been described herein above. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.
[0011] All of these embodiments are intended to be within the scope of the invention herein disclosed. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a perspective view of an LED module having features in accordance with the present invention.
[0013] FIG. 2 is a schematic side view of a typical pre-packaged LED lamp.
[0014] FIG. 3 is a top plan view of the LED module of FIG. 1 .
[0015] FIG. 4 is a side plan view of the apparatus of FIG. 3 .
[0016] FIG. 5 is a close-up side view of the apparatus of FIG. 3 mounted on a heat conductive member.
[0017] FIG. 6 is another sectional side view of the apparatus of FIG. 3 mounted onto a heat conductive flat surface.
[0018] FIG. 7 is a side plan view of an LED module having features in accordance with another embodiment of the present invention.
[0019] FIG. 8 is a side plan view of another LED module having features in accordance with yet another embodiment of the present invention.
[0020] FIG. 9 is a perspective view of an illumination apparatus having features in accordance with the present invention.
[0021] FIG. 10 is a side view of the apparatus of FIG. 9 .
[0022] FIG. 11 is a bottom view of the apparatus of FIG. 9 .
[0023] FIG. 12 is a top view of the apparatus of FIG. 9 .
[0024] FIG. 13 is a schematic view of the apparatus of FIG. 9 mounted on a theater seat row end.
[0025] FIG. 14 is a side view of the apparatus of FIG. 13 showing the mounting orientation.
[0026] FIG. 15 is a side view of a mounting barb.
[0027] FIG. 16 is a front plan view of the illumination apparatus of FIG. 9 .
[0028] FIG. 17 is a cutaway side plan view of the apparatus of FIG. 20 .
[0029] FIG. 18 is a schematic plan view of a heat sink base plate.
[0030] FIG. 19 is a close-up side sectional view of an LED module mounted on a mount tab of a base plate.
[0031] FIG. 20 is a plan view of a lens for use with the apparatus of FIG. 9 .
[0032] FIG. 21 is a perspective view of a channel illumination apparatus incorporating LED modules having features in accordance with the present invention.
[0033] FIG. 22 is a close-up side view of an LED module mounted on a mount tab.
[0034] FIG. 23 is a partial view of a wall of the apparatus of FIG. 21 , taken along line 23 - 23 .
[0035] FIG. 24 is a top view of an LED module mounted to a wall of the apparatus of FIG. 21 .
[0036] FIG. 25 is a top view of an alternative embodiment of an LED module mounted to a wall of the apparatus of FIG. 21 .
[0037] FIG. 26A is a side view of an alternative embodiment of a lighting module being mounted onto a channel illumination apparatus wall member.
[0038] FIG. 26B shows the apparatus of the arrangement of FIG. 26A with the lighting module installed.
[0039] FIG. 26C shows the arrangement of FIG. 26B with a lens installed on the wall member.
[0040] FIG. 26D shows a side view of an alternative embodiment of a lighting module installed on a channel illumination apparatus wall member.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0041] With reference first to FIG. 1 , an embodiment of a light-emitting diode (LED) lighting module 30 is disclosed. In the illustrated embodiment, the LED module 30 includes five pre-packaged LEDs 32 arranged on one side of the module 30 . It is to be understood, however, that LED modules having features in accordance with the present invention can be constructed having any number of LEDs 32 mounted in any desired configuration.
[0042] With next reference to FIG. 2 , a typical pre-packaged LED 32 includes a diode chip 34 encased within a resin body 36 . The body 36 typically has a focusing lens portion 38 . A negative lead 40 connects to an anode side 42 of the diode chip 34 and a positive lead 44 connects to a cathode side 46 of the diode chip 34 . The positive lead 44 preferably includes a reflector portion 48 to help direct light from the diode 34 to the lens portion 38 .
[0043] With next reference to FIGS. 1-5 , the LED module 30 preferably comprises the five pre-packaged LED lamps 32 mounted in a linear array on a circuit board 50 and electrically connected in series. The illustrated embodiment employs pre-packaged aluminum indium gallium phosphide (AlInGaP) LED lamps 32 such as model HLMT-PL00, which is available from Hewlett Packard. In the illustrated embodiment, each of the pre-packaged LEDs is substantially identical so that they emit the same color of light. It is to be understood, however, that nonidentical LEDs may be used to achieve certain desired lighting effects.
[0044] The illustrated circuit board 50 preferably is about 0.05 inches thick, 1 inch long and 0.5 inch wide. It includes three layers: a copper contact layer 52 , an epoxy dielectric layer 54 and an aluminum main body layer 56 . The copper contact layer 52 is made up of a series of six elongate and generally parallel flat copper plates 60 that are adapted to attach to the leads 40 , 44 of the LEDs 32 . Each of the copper contacts 60 is electrically insulated from the other copper contacts 60 by the dielectric layer 54 . Preferably, the copper contacts 60 are substantially coplanar.
[0045] The pre-packaged LEDs 32 are attached to one side of the circuit board 50 , with the body portion 36 of each LED generally abutting a side of the circuit board 50 . The LED lens portion 38 is thus pointed outwardly so as to direct light in a direction substantially coplanar with the circuit board 50 . The LED leads 40 , 44 are soldered onto the contacts 60 in order to create a series array of LEDs. Excess material from the leads of the individual pre-packaged LED lamps may be removed, if desired. Each of the contacts 60 , except for the first and last contact 62 , 64 , have both a negative lead 40 and a positive lead 44 attached thereto. One of the first and last contacts 62 , 64 has only a negative lead 40 attached thereto; the other has only a positive lead 44 attached thereto.
[0046] A bonding area of the contacts accommodates the leads 40 , 44 , which are preferably bonded to the contact 60 with solder 68 ; however, each contact 60 preferably has a surface area much larger than is required for adequate bonding in the bonding area 66 . The enlarged contact surface area allows each contact 60 to operate as a heat sink, efficiently absorbing heat from the LED leads 40 , 44 . To maximize this role, the contacts 60 are shaped to be as large as possible while still fitting upon the circuit board 50 .
[0047] The dielectric layer 54 preferably has strong electrical insulation properties but also relatively high heat conductance properties. In the illustrated embodiment, the layer 54 is preferably as thin as practicable. For example in the illustrated embodiment, the dielectric layer 54 comprises a layer of Thermagon® epoxy about 0.002 inches thick.
[0048] It is to be understood that various materials and thicknesses can be used for the dielectric layer 54 . Generally, the lower the thermal conductivity of the material used for the dielectric layer, the thinner that dielectric layer should be in order to maximize heat transfer properties of the module. For example, in the illustrated embodiment, the layer of epoxy is very thin. Certain ceramic materials, such as beryllium oxide and aluminum nitride, are electrically non-conductive but highly thermally conductive. When the dielectric layer is constructed of such materials, it is not as crucial for the dielectric layer to be so very thin, because of the high thermal conductivity of the material.
[0049] In the illustrated embodiment, the main body 56 makes up the bulk of the thickness of the circuit board 50 and preferably comprises a flat aluminum plate. As with each of the individual contacts 60 , the main body 56 functions as a heat conduit, absorbing heat from the contacts 60 through the dielectric layer 54 to conduct heat away from the LEDs 32 . However, rather than just absorbing heat from a single LED 32 , the main body 56 acts as a common heat conduit, absorbing heat from all of the contacts 60 . As such, in the illustrated embodiment, the surface area of the main body 56 is about the same as the combined surface area of all of the individual contacts 60 . The main body 56 can be significantly larger than shown in the illustrated embodiment, but its relatively compact shape is preferable in order to increase versatility when mounting the light module 30 . Additionally, the main body 56 is relatively rigid and provides structural support for the lighting module 30 .
[0050] In the illustrated embodiment, aluminum has been chosen for its high thermal conductance properties and ease of manufacture. It is to be understood, however, that any material having advantageous thermal conductance properties, such as having thermal conductivity greater than about 100 watts per meter per Kelvin (W/m-K), would be acceptable.
[0051] A pair of holes 70 are preferably formed through the circuit board 50 and are adapted to accommodate a pair of aluminum pop rivets 72 . The pop rivets 72 hold the circuit board 50 securely onto a heat conductive mount member 76 . The mount member 76 functions as or communicates with a heat sink. Thus, heat from the LEDs 32 is conducted with relatively little resistance through the module 30 to the attached heat sink 76 so that the junction temperature of the diode chip 34 within the LED 32 does not exceed a maximum desired level.
[0052] With reference again to FIGS. 3 and 5 , a power supply wire 78 is attached across the first and last contacts 62 , 64 of the circuit board 50 so that electrical current is provided to the series-connected LEDs 32 . The power supply is preferably a 12-volt system and may be AC, DC or any other suitable power supply. A 12-volt AC system may be fully rectified.
[0053] The small size of the LED module 30 provides versatility so that modules can be mounted at various places and in various configurations. For instance, some applications will include only a single module for a particular lighting application, while other lighting applications will employ a plurality of modules electrically connected in parallel relative to each other.
[0054] It is also to be understood that any number of LEDs can be included in one module. For example, some modules may use two LEDs, while other modules may use 10 or more LEDs. One manner of determining the number of LEDs to include in a single module is to first determine the desired operating voltage of a single LED of the module and also the voltage of the power supply. The number of LEDs desired for the module is then roughly equal to the voltage of the power supply divided by the operating voltage of each of the LEDs.
[0055] The present invention rapidly conducts heat away from the diode chip 34 of each LED 32 so as to permit the LEDs 32 to be operated in regimes that exceed normal operating parameters of the pre-packaged LEDs 32 . In particular, the heat sinks allow the LED circuit to be driven in a continuous, non-pulsed manner at a higher long-term electrical current than is possible for typical LED mounting configurations. This operating current is substantially greater than manufacturer-recommended maximums. The optical emission of the LEDs at the higher current is also markedly greater than at manufacturer-suggested maximum currents.
[0056] The heat transfer arrangement of the LED modules 30 is especially advantageous for pre-packaged LEDs 32 having relatively small packaging and for single-diode LED lamps. For instance, the HLMT-PL00 model LED lamps used in the illustrated embodiment employ only a single diode, but since heat can be drawn efficiently from that single diode through the leads and circuit board and into the heat sink, the diode can be run at a higher current than such LEDs are traditionally operated. At such a current, the single-diode LED shines brighter than LED lamps that employ two or more diodes and which are brighter than a single-diode lamp during traditional operation. Of course, pre-packaged LED lamps having multiple diodes can also be employed with the present invention. It is also to be understood that the relatively small packaging of the model HLMT-PL00 lamps aids in heat transfer by allowing the heat sink to be attached to the leads closer to the diode chip.
[0057] With next reference to FIG. 5 , a first reflective layer 80 is preferably attached immediately on top of the contacts 60 of the circuit board 50 and is held in position by the rivets 72 . The first reflector 80 preferably extends outwardly beyond the LEDs 32 . The reflective material preferably comprises an electrically non-conductive film such as visible mirror film available from 3M. A second reflective layer 82 is preferably attached to the mount member 76 at a point immediately adjacent the LED lamps 32 . The second strip 82 is preferably bonded to the mount surface 76 using adhesive in a manner known in the art.
[0058] With reference also to FIG. 6 , the first reflective strip 80 is preferably bent so as to form a convex reflective trough about the LEDs 32 . The convex trough is adapted to direct light rays emitted by the LEDs 32 outward with a minimum of reflections between the reflector strips 80 , 82 . Additionally, light from the LEDs is limited to being directed in a specified general direction by the reflecting films 80 , 82 . As also shown in FIG. 6 , the circuit board 50 can be mounted directly to any mount surface 76 .
[0059] In another embodiment, the aluminum main body portion 56 may be of reduced thickness or may be formed of a softer metal so that the module 30 can be partially deformed by a user. In this manner, the module 30 can be adjusted to fit onto various surfaces, whether they are flat or curved. By being able to adjust the fit of the module to the surface, the shared contact surface between the main body and the adjacent heat sink is maximized, improving heat transfer properties. Additional embodiments can use fasteners other than rivets to hold the module into place on the mount surface/heat sink material. These additional fasteners can include any known fastening means such as welding, heat conductive adhesives, and the like.
[0060] As discussed above, a number of materials may be used for the circuit board portion of the LED module. With specific reference to FIG. 7 , another embodiment of an LED module 86 comprises a series of elongate, flat contacts 88 similar to those described above with reference to FIG. 3 . The contacts 88 are mounted directly onto the main body portion 89 . The main body 89 comprises a rigid, substantially flat ceramic plate. The ceramic plate makes up the bulk of the circuit board and provides structural support for the contacts 88 . Also, the ceramic plate has a surface area about the same as the combined surface area of the contacts. In this manner, the plate is large enough to provide structural support for the contacts 88 and conduct heat away from each of the contacts 88 , but is small enough to allow the module 86 to be relatively small and easy to work with. The ceramic plate 89 is preferably electrically non-conductive but has high heat conductivity. Thus, the contacts 88 are electrically insulated relative to each other, but heat from the contacts 88 is readily transferred to the ceramic plate 89 and into an adjoining heat sink.
[0061] With next reference to FIG. 8 , another embodiment of an LED lighting module 90 is shown. The LED module 90 comprises a circuit board 92 having features substantially similar to the circuit board 50 described above with reference to FIG. 3 . The diode portion 94 of the LED 96 is mounted substantially directly onto the contacts 60 of the lighting module 90 . In this manner, any thermal resistance from leads of pre-packaged LEDs is eliminated by transferring heat directly from the diode 94 onto each heat sink contact 60 , from which the heat is conducted to the main body 56 and then out of the module 90 . In this configuration, heat transfer properties are yet further improved.
[0062] As discussed above, an LED module having features as described above can be used in many applications such as, for example, indoor and outdoor decorative lighting, commercial lighting, spot lighting, and even room lighting. With next reference to FIGS. 9-12 , a self-contained lighting apparatus 100 incorporates an LED module 30 and can be used in many such applications. In the illustrated embodiment, the lighting apparatus 100 is adapted to be installed on the side of a row of theater seats 102 , as shown in FIG. 13 , and is adapted to illuminate an aisle 104 next to the theater seats 102 .
[0063] The self-contained lighting apparatus 100 comprises a base plate 106 , a housing 108 , and an LED module 30 arranged within the housing 108 . As shown in FIGS. 9, 10 and 13 , the base plate 106 is preferably substantially circular and has a diameter of about 5.75 inches. The base plate 106 is preferably formed of 1/16 th inch thick aluminum sheet. As described in more detail below, the plate functions as a heat sink to absorb and dissipate heat from the LED module. As such, the base plate 106 is preferably formed as large as is practicable, given aesthetic and installation concerns.
[0064] As discussed above, the lighting apparatus 100 is especially adapted to be mounted on an end panel 110 of a row of theater chairs 102 in order to illuminate an adjacent aisle 104 . As shown in FIGS. 13 and 14 , the base plate 106 is preferably installed in a vertical orientation. Such vertical orientation aids conductive heat transfer from the base plate 106 to the environment.
[0065] The base plate 106 includes three holes 112 adapted to facilitate mounting. A ratcheting barb 116 (see FIG. 15 ) secures the plate 106 to the panel 110 . The barb 116 has an elongate main body 118 having a plurality of biased ribs 120 and terminating at a domed top 122 .
[0066] To mount the apparatus on the end panel 110 , a hole is first formed in the end panel surface on which the apparatus is to be mounted. The base plate holes 112 are aligned with mount surface holes and the barbs 116 are inserted through the base plate 106 into the holes. The ribs 120 prevent the barbs 116 from being drawn out of the holes once inserted. Thus, the apparatus is securely held in place and cannot be easily removed. The barbs 116 are especially advantageous because they enable the device to be mounted on various surfaces. For example, the barbs will securely mount the illumination apparatus on wooden or fabric surfaces.
[0067] With reference next to FIGS. 16-19 , a mount tab 130 is provided as an integral part of the base plate 106 . The mounting tab 130 is adapted to receive an LED module 30 mounted thereon. The tab 30 is preferably plastically deformed along a hinge line 132 to an angle θ between about 20-45° relative to the main body 134 of the base plate 106 . More preferably, the mounting tab 130 is bent at an angle θ of about 33°. The inclusion of the tab 130 as an integral part of the base plate 106 facilitates heat transfer from the tab 130 to the main body 134 of the base plate. It is to be understood that the angle θ of the tab 130 relative to the base plate body 134 can be any desired angle as appropriate for the particular application of the lighting apparatus 100 .
[0068] A cut out portion 136 of the base plate 106 is provided surrounding the mount tab 130 . The cut out portion 136 provides space for components of the mount tab 130 to fit onto the base plate 106 . Also, the cut out portion 136 helps define the shape of the mount tab 130 . As discussed above, the mount tab 130 is preferably plastically deformed along the hinge line 132 . The length of the hinge line 132 is determined by the shape of the cut out portion 136 in that area. Also, a hole 138 is preferably formed in the hinge line 132 . The hole 138 further facilitates plastic deformation along the hinge line 132 .
[0069] Power for the light source assembly 100 is preferably provided through a power cord 78 that enters the apparatus 100 through a back side of the base plate 106 . The cord 78 preferably includes two 18 AWG conductors surrounded by an insulating sheet. Preferably, the power supply is in the low voltage range. For example, the power supply is preferably a 12-volt alternating current power source. As depicted in FIG. 18 , power is preferably first provided through a full wave ridge rectifier 140 which rectifies the alternating current in a manner known in the art so that substantially all of the current range can be used by the LED module 40 . In the illustrated embodiment, the LEDs are preferably not electrically connected to a current-limiting resistor. Thus, maximum light output can be achieved. It is to be understood, however, that resistors may be desirable in some embodiments to regulate current. Supply wires 142 extend from the rectifier 140 and provide rectified power to the LED module 30 mounted on the mounting tab 130 .
[0070] With reference again to FIGS. 9-12 , 16 and 17 , the housing 108 is positioned on the base plate 106 and preferably encloses the wiring connections in the light source assembly 100 . The housing 108 is preferably substantially semi-spherical in shape and has a notch 144 formed on the bottom side. A cavity 146 is formed through the notch 144 and allows visual access to the light source assembly 100 . A second cavity 148 is formed on the top side and preferably includes a plug 150 which may, if desired, include a marking such as a row number. In an additional embodiment, a portion of the light from the LED module 30 , or even from an alternative light source, may provide light to light up the aisle marker.
[0071] The housing 108 is preferably secured to the base plate 106 by a pair of screws 152 . Preferably, the screws 152 extend through countersunk holes 154 in the base plate 106 . This enables the base plate 106 to be substantially flat on the back side, allowing the plate to be mounted flush with the mount surface. As shown in FIG. 17 , threaded screw receiver posts 156 are formed within the housing 108 and are adapted to accommodate the screw threads.
[0072] The LED module 30 is attached to the mount tab 130 by the pop rivets 72 . The module 30 and rivets 72 conduct heat from the LEDs 32 to the mount tab 130 . Since the tab 130 is integrally formed as a part of the base plate 106 , heat flows freely from the tab 130 to the main body 134 of the base plate. The base plate 106 has high heat conductance properties and a relatively large surface area, thus facilitating efficient heat transfer to the environment and allowing the base plate 106 to function as a heat sink.
[0073] As discussed above, the first reflective strip 80 of the LED module 30 is preferably bent so as to form a convex trough about the LEDs. The second reflector strip 82 is attached to the base plate mount tab 130 at a point immediately adjacent the LED lamps 32 . Thus, light from the LEDs is collimated and directed out of the bottom cavity 146 of the housing 108 , while minimizing the number of reflections the light must make between the reflectors (see FIG. 6 ). Such reflections may each reduce the intensity of light reflected.
[0074] A lens or shield 160 is provided and is adapted to be positioned between the LEDs 32 and the environment outside of the housing cavity 108 . The shield 160 prevents direct access to the LEDs 32 and thus prevents harm that may occur from vandalism or the like, but also transmits light emitted by the light source 100 .
[0075] FIG. 20 shows an embodiment of the shield 160 adapted for use in the present invention. As shown, the shield 160 is substantially lenticularly shaped and has a notch 162 formed on either end thereof. With reference back to FIG. 18 , the mounting tab 130 of the base plate 106 also has a pair of notches 164 formed therein.
[0076] As shown in FIG. 16 , the lens/shield notches 162 are adapted to fit within the tab notches 164 so that the shield 160 is held in place in a substantially arcuate position. The shield thus, in effect, wraps around one side of the LEDs 32 . When the shield 160 is wrapped around the LEDs 32 , the shield 160 contacts the first reflector film 80 , deflecting the film 80 to further form the film in a convex arrangement. The shield 160 is preferably formed of a clear polycarbonate material, but it is to be understood that the shield 160 may be formed of any clear or colored transmissive material as desired by the user.
[0077] The LED module 30 of the present invention can also be used in applications using a plurality of such modules 30 to appropriately light a lighting apparatus such as a channel illumination device. Channel illumination devices are frequently used for signage including borders and lettering. In these devices, a wall structure outlines a desired shape to be illuminated, with one or more channels defined between the walls. A light source is mounted within the channel and a translucent diffusing lens is usually arranged at the top edges of the walls so as to enclose the channel. In this manner, a desired shape can be illuminated in a desired color as defined by the color of the lens.
[0078] Typically, a gas-containing light source such as a neon light is custom-shaped to fit within the channel. Although the diffusing lens is placed over the light source, the light apparatus may still produce “hot spots,” which are portions of the sign that are visibly brighter than other portions of the sign. Such hot spots result because the lighting apparatus shines directly at the lens, and the lens may have limited light-diffusing capability. Incandescent lamps may also be used to illuminate such a channel illumination apparatus; however, the hot spot problem typically is even more pronounced with incandescent lights.
[0079] Both incandescent and gas-filled lights have relatively high manufacturing and operation costs. For instance, gas-filled lights typically require custom shaping and installation and therefore can be very expensive to manufacture. Additionally, both incandescent and gas-filled lights have high power requirements.
[0080] With reference next to FIG. 21 , an embodiment of a channel illumination apparatus 170 is disclosed comprising a casing 172 in the shape of a “P.” The casing 172 includes a plurality of walls 174 and a bottom 176 , which together define at least one channel. The surfaces of the walls 174 and bottom 176 are diffusely-reflective, preferably being coated with a flat white coating. The walls 174 are preferably formed of a durable sturdy metal having relatively high heat conductivity. A plurality of LED lighting modules 30 are mounted to the walls 174 of the casing 172 in a spaced-apart manner. A translucent light-diffusing lens (not shown) is preferably disposed on a top edge 178 of the walls 174 and encloses the channel.
[0081] With next reference to FIG. 22 , the pop rivets 72 hold the LED module 30 securely onto a heat conductive mount tab 180 . The mount tab 180 , in turn, may be connected, by rivets 182 or any other fastening means, to the walls 174 of the channel apparatus as shown in FIG. 23 . Preferably, the connection of the mount tab 180 to the walls 174 facilitates heat transfer from the tab 180 to the wall 174 . The channel wall has a relatively large surface area, facilitating efficient heat transfer to the environment and enabling the channel wall 174 to function as a heat sink.
[0082] In additional embodiments, the casing 172 may be constructed of materials, such as certain plastics, that may not be capable of functioning as heat sinks because of inferior heat conductance properties. In such embodiments, the LED module 30 can be connected to its own relatively large heat sink base plate, which is mounted to the wall of the casing. An example of such a heat sink plate in conjunction with an LED lighting module has been disclosed above with reference to the self-contained lighting apparatus 100 .
[0083] With continued reference to FIGS. 22 and 23 , the LED modules 30 are preferably electrically connected in parallel relative to other modules 30 in the illumination apparatus 170 . A power supply cord 184 preferably enters through a wall 174 or bottom surface 176 of the casing 172 and preferably comprises two 18 AWG main conductors 186 . Short wires 188 are attached to the first and last contacts 62 , 64 of each module 30 and preferably connect with respective main conductors 186 using insulation displacement connectors (IDCs) 190 as shown in FIG. 23 .
[0084] Although the LEDs 32 in the modules 30 are operated at currents higher than typical LEDs, the power efficiency characteristic of LEDs is retained. For example, a typical channel light employing a neon-filled light could be expected to use about 60 watts of power during operation. A corresponding channel illumination apparatus 170 using a plurality of LED modules can be expected to use about 4.5 watts of power.
[0085] With reference again to FIG. 23 , the LED modules 30 are preferably positioned so that the LEDs 32 face generally downwardly, directing light away from the lens. The light is preferably directed to the diffusely-reflective wall and bottom surfaces 174 , 176 of the casing 172 . The hot spots associated with more direct forms of lighting, such as typical incandescent and gas-filled bulb arrangements, are thus avoided.
[0086] The reflectors 80 , 82 of the LED modules 30 aid in directing light rays emanating from the LEDs toward the diffusely-reflective surfaces. It is to be understood, however, that an LED module 30 not employing reflectors can also be appropriately used.
[0087] The relatively low profile of each LED module 30 facilitates the indirect method of lighting because substantially no shadow is created by the module when it is positioned on the wall 174 . A higher-profile light module would cast a shadow on the lens, producing an undesirable, visibly darkened area. To minimize the potential of shadowing, it is desired to space the modules 30 and accompanying power wires 186 , 188 a distance of at least about ½ inch from the top edge 178 of the wall 174 . More preferably, the modules 30 are spaced more than one inch from the top 178 of the wall 174 .
[0088] The small size and low profile of the LED modules 30 enables the modules to be mounted at various places along the channel wall 174 . For instance, with reference to FIGS. 21 and 24 , light modules 30 must sometimes be mounted to curving portions 192 of walls 174 . The modules 30 are preferably about 1 inch to 1-½ inch long, including the mounting tab 180 , and thus can be acceptably mounted to a curving wall 192 . As shown, the mounting tab 180 may be separated from the curving wall 192 along a portion of its length, but the module is small enough that it is suitable for riveting to the wall.
[0089] In an additional embodiment shown in FIG. 25 , the module 30 comprises the circuit board without the mount tab 180 . In such an embodiment, the circuit board 50 may be mounted directly to the wall, having an even better fit relative to the curved surface 192 than the embodiment using a mount tab. In still another embodiment, the LED module's main body 56 is formed of a bendable material, which allows the module to fit more closely and easily to the curved wall surface.
[0090] Although the LED modules 30 disclosed above are mounted to the channel casing wall 174 with rivets 182 , it is to be understood that any method of mounting may be acceptably used. With reference next to FIGS. 26 A-C, an additional embodiment comprises an LED module 30 mounted to a mounting tab 200 which comprises an elongate body portion 202 and a clip portion 204 . The clip portion 204 is urged over the top edge 178 of the casing wall 172 , firmly holding the mounting tab 200 to the wall 174 as shown in FIG. 26B . The lens 206 preferably has a channel portion 208 which is adapted to engage the top edge 178 of the casing wall 174 and can be fit over the clip portion 204 of the mount tab 200 as shown in FIGS. 26B and 26C . This mounting arrangement is simple and provides ample surface area contact between the casing wall 174 and the mounting tab 200 so that heat transfer is facilitated.
[0091] In the embodiment shown in FIG. 21 , the casing walls 174 are about 3 to 4 inches deep and the width of the channel is about 3 to 4 inches between the walls. In an apparatus of this size, LED modules 30 positioned on one side of the channel can provide sufficient lighting. The modules are preferably spaced about 5-6 inches apart. As may be anticipated, larger channel apparatus will likely require somewhat different arrangements of LED modules, including employing more LED modules. For example, a channel illumination apparatus having a channel width of 1 to 2 feet may employ LED modules on both walls and may even use multiple rows of LED modules. Additionally, the orientation of each of the modules may be varied in such a large channel illumination apparatus. For instance, with reference to FIG. 26D , some of the LED modules may desirably be angled so as to direct light at various angles relative to the diffusely reflective surfaces.
[0092] In order to avoid creating hot spots, a direct light path from the LED 32 to the lens 206 is preferably avoided. However, it is to be understood that pre-packaged LED lamps 32 having diffusely-reflective lenses may advantageously be directed toward the channel letter lens 206 .
[0093] Using LED modules 30 to illuminate a channel illumination apparatus 170 provides significant savings during manufacturing. For example, a number of LED modules, along with appropriate wiring and hardware, can be included in a kit which allows a technician to easily assemble a light by simply securing the modules in place along the wall of the casing and connecting the wiring appropriately using the IDCs. Although rivet holes may have to be drilled through the wall, there is no need for custom shaping, as is required with gas-filled bulbs. Accordingly, manufacturing effort and costs are significantly reduced.
[0094] Individual LEDs emit generally monochromatic light. Thus, it is preferable that an LED type be chosen which corresponds to the desired illumination color. Additionally, the diffuser is preferably chosen to be substantially the same color as the LEDs. Such an arrangement facilitates desirable brightness and color results. It is also to be understood that the diffusely-reflective wall and bottom surfaces may advantageously be coated to match the desired illumination color.
[0095] Although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically-disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. In addition, while a number of variations of the invention have been shown and described in detail, other modifications, which are within the scope of this invention, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or subcombinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the invention. Accordingly, 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 invention. Thus, it is intended that the scope of the present invention 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 modular light emitting diode (LED) mounting configuration is provided including a light source module having a plurality of pre-packaged LEDs arranged in a serial array. The module includes a heat conductive body portion adapted to conduct heat generated by the LEDs to an adjacent heat sink. As a result, the LEDs are able to be operated with a higher current than normally allowed. Thus, brightness and performance of the LEDs is increased without decreasing the life expectancy of the LEDs. The LED modules can be used in a variety of illumination applications employing one or more modules. | 8 |
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of application Ser. No. 10/797,312 filed Mar. 10, 2004.
FIELD OF THE INVENTION
[0002] The present invention relates to packaging materials that are made from paper, film, or a paper/film combination that have tear tapes made from the same or similar material and applied across the web. The tear tapes may be pulled to tear off and open one end of the packaging leaving the remaining packaging intact to serve as a storage and dispenser for the package material.
BACKGROUND OF THE INVENTION
[0003] To date tear tapes have only been used with gum and cigarette packaging. Usually, once packages are open they cannot be used to store the remainder of what is in the package. Opening of the package destroys the integrity of the package. One example of traditional packaging is for ream wraps.
[0004] Traditional packaging for wrapped reams (i.e., 500 sheets) of cut paper (8½×11, etc.) for copy machines, computers, printers, and other applications involves folding and overlapping the tops and bottom ends of the packaging and sealing the folded ends using heat or adhesive materials. Reams are most commonly packaged for shipping, storage, and retail sale in ream wrap made of various materials, including the traditional paper (polymer coated or two papers laminated with polymer), plastic film, or a paper/film combination. In addition to encasing the reams of paper, the wrap materials protect the paper from physical damage and moisture pickup during shipping and storing. The wrap materials also protect paper products from physical damage during repeated handling and stocking on retail shelves.
[0005] As small offices and home offices have proliferated, the distribution and sale of reams of paper have changed from boxes for large users to wrapped individual reams for retail stores and the small office and home office users. A major disadvantage of traditional ream wrap packaging for the individual user is that the current method of opening the packaging destroys the integrity of the entire wrapped ream. For instance, when the folded bottom or top end of the wrapped ream is torn open, the entire folded package opens, destroying the integrity of the wrapped structure and exposing and scattering the loose sheets of paper remaining in the ream. For the individual user who uses only a portion of the ream at a time and needs to store the remaining sheets, the unbound papers pose an inconvenience and impediment to storage. Since the structural support of the original packaging is compromised, the result for individual users is often physical damage to the unbound sheets of paper being stored for future use. The current marketplace demands a ream wrapper that may be opened so that a user may remove part of a ream and store the remaining sheets in a structure that prevents physical damage and scattering of loose papers.
SUMMARY OF THE INVENTION
[0006] The present invention relates to a package that is opened so that a user may remove part of the contents of the package and store the remaining contents in a structure that prevents physical damage and scattering of loose parts.
[0007] The present invention relates to a ream wrapper that is opened so that a user removes part of a ream of paper and stores remaining sheets in the ream wrapper. The opened ream wrapper prevents physical damage to the remaining sheets and prevents scattering of loose pieces of paper.
[0008] It is an object of the present invention for the package to be opened by at least one tear tape.
[0009] The present invention relates to a packaging material that has one or more tear tapes inserted in the packaging material across the web so that it surrounds the entire width of the packaging material. It is an object of the present invention for the tear tape to comprise a strip of paper or film that is drawn through or coated with wax. It is an object of the present invention for the tear tape to be 1/32″ to 1½″. It is an object of the present invention for the tear tape to be torn lengthwise, not across the width of the tear tape.
[0010] The present invention also relates to packaging materials that are used to wrap products, such as paper towels, napkins, toilet paper, or other consumer products, that have a tear tape applied across the web either on the packaging line or during the manufacturing of the packaging materials.
[0011] It is an object of the present invention that the packaging materials or ream wrap be comprised of a paper, film, or paper/film substrate.
[0012] It is an object of the present invention for the tear tape to comprise a non-coated strip of paper or film that is heat-sealed onto the packaging material. It is an object of the present invention for the tear tape to comprise a strip of high strength poly film, such as polyethylene or polypropylene, with adhesive on one side of the strip. It is an object of the present invention for the tear tape to comprise identical material from which the packaging material itself is made. It is an object of the present invention for the packaging material and the tear tape to both be made of shrink wrap.
[0013] It is an object of the present invention for the tear tape to be printed with a company name, logo, design, or other statement. It is an object of the present invention for the tear tape to be attached by an adhesive. It is an object of the present invention for the packaging material to have a tear tape on top of the packaging material which opens the top of the packaging material but keeps the integrity of the packaging material. It is an object of the present invention for the packaging material to have a tear tape that does not completely remove a section of the packaging material.
[0014] The present invention relates to a method for opening a package having multiple contents comprising: pulling a tear tape across a packaging material, opening a portion of the packaging material and removing one sealed end of the packaging material while the remaining packaging material is left intact for storage and dispensing of the contents of the package.
[0015] An object of the present invention is to enable large users of reamed papers, such as insurance companies and other large users, to have a quicker way of opening multiple reams. Large users typically open and use several hundred reams of paper each business day. Currently, these users crack open and tear each individual ream by hand. The use of a tear tape to tear open the end of the ream enables this procedure to be done more quickly and efficiently. The user could tear the tape to remove one end of the packaging and quickly pull off the other end of the wrapper.
[0016] It is an object of the present invention to enable users of paper towels, napkins, toilet paper, tissues, envelopes, cheese slices, or other consumer products, to have a quicker way of opening packaging for these products. Currently, users of these products tear open the packaging. These users currently cannot store the remaining contents of the package, and therefore the contents of the package are exposed to other factors which cause a shorter life for these products due to environmental factors.
[0017] It is a further object of the present invention for the tear tape to be inserted in the ream wrap across the web so that it surrounds the entire width of the wrapped ream. When pulled, the tear tape opens one portion of the top or bottom end of the ream wrap, much like the tear tape on the film package encasing a pack of cigarettes or gum. When pulled, the tear tape opens and enables the removal of one of the sealed ends of the ream wrap while leaving the remaining structure intact for storage and dispensing of the remaining ream of paper.
[0018] The present invention also relates to a method for opening a packaged product comprising: pulling a tear tape across the packaging, opening a portion of the wrapper and removing one sealed end of the wrapper while the remaining ream wrap is left intact for storage, dispensing, or other purposes. It is an object of this invention that the tear tape for such packaging materials be applied across the web.
[0019] The present invention relates to packaging which when directly open allows a user to use a product contained within the packaging, without having to remove further packaging from the product. For example, if a user were to use the tear tape of the present invention with a wrapper for toilet paper, when the wrapper would be open, the user could directly remove one roll of toilet paper and then store the other rolls in the packaging. A second example is a ream wrap which when open with a tear tape a user can use a sheet of paper. Previously, the tear tape was used in a packaging for cigarettes wherein once the tear tape was removed the cigarettes were still protected by being fully enclosed in a packaging.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a front view showing the ream wrap having a tear tape in the closed position;
[0021] FIG. 2 is a ream wrap having the tear tape in the open position;
[0022] FIG. 3 is a cross sectional view of the tear tape shown in FIG. 1 ;
[0023] FIG. 4 is a cross sectional view of the tear tape shown in FIG. 2 ;
[0024] FIG. 5 shows the ream wrap after a tear tape has removed a section of the ream wrap;
[0025] FIG. 6 is a front view showing the ream wrap having a tear tape in the closed position;
[0026] FIG. 7 is a ream wrap having the tear tape in the open position;
[0027] FIG. 8 is a cross sectional view of the tear tape shown in FIG. 6 ;
[0028] FIG. 9 is a cross sectional view of the tear tape shown in FIG. 7 ;
[0029] FIG. 10 is a front view showing the ream wrap having a tear tape in the closed position;
[0030] FIG. 11 is a ream wrap having the tear tape in the open position;
[0031] FIG. 12 is a cross sectional view of the tear tape shown in FIG. 10 ;
[0032] FIG. 13 is a cross sectional view of the tear tape shown in FIG. 11 ;
[0033] FIG. 14 is a top view showing the ream wrap in the closed position;
[0034] FIG. 15 is a top view showing the ream wrap in the open position;
[0035] FIG. 16 is a top view of the ream wrap in the closed position; and
[0036] FIG. 17 is a top view of the ream wrap in the open position.
DETAILED DESCRIPTION OF THE INVENTION
[0037] The present invention relates to a method of wrapping reams of paper or other products involving the insertion of one or more tear tapes into the ream wrap or packaging material. The tear tape, when pulled, enables the opening and removal of a sealed end of the wrapper leaving a portion of the wrapper intact to protect, store, and dispense partial reams of paper or other products. The tear tape is inserted in the ream wrap or packaging materials across the web and can be applied to any type of ream wrap packaging or other packaging materials, including paper, film, paper/film combination, or shrink wrap.
[0038] In one embodiment, the tear tape comprises a strip of paper or film that is drawn through or coated with wax. The wax is used to adhere the tear tape to the ream wrap. The tear tape is 1/32″ to 1½″ in width and is torn lengthwise, not across the width of the strip.
[0039] In another embodiment, the tear tape comprises a non-coated strip of paper or film that is heat-sealed onto the ream wrap. The tear tape is 1/32″ to 1½″ in width and is torn lengthwise, not across the width of the strip.
[0040] In another embodiment, the tear tape comprises a strip of high strength poly film, such as polyethylene or polypropylene, with adhesive on one side of the strip. The adhesive is used to adhere the strip to the ream wrap. The tear tape is 1/32″ to 1½″ in width and is torn lengthwise, not across the width of the strip.
[0041] In another embodiment, the tear tape comprises the identical material from which the ream wrap itself is made. For instance, in the case of shrink wrap ream wrap, the tear tape would be made of a similar film material so that it would shrink in proportion to the ream wrap itself. The tear tape is 1/32″ to 1½″ in width and is torn lengthwise, not across the width of the tape.
[0042] In any of these embodiments, the tear tape may or may not be printed with a company name, logo, design, or other statement.
[0043] Although the figures show the tear tape in association with a ream wrap, the tear tape can be used with any other packaging material as described in the specification.
[0044] FIG. 1 shows a ream wrap 10 having a tear tape 20 wherein the ream wrap is closed. FIG. 2 shows ream wrap 50 having the tear tape 60 , which has been pulled across the ream wrap leaving an opening 70 .
[0045] FIG. 3 shows a cross sectional view of the tear tape attached to the ream wrap shown in FIG. 1 . FIG. 4 shows a cross sectional view of the tear tape shown in FIG. 2 . FIG. 5 shows the ream wrap 100 after a tear tape has removed a section of the ream wrap 110 allowing the paper 120 to be retrieved and stored in the ream wrap.
[0046] FIG. 6 shows a ream wrap 200 having a tear tape 210 wherein the ream wrap is closed. FIG. 7 shows a ream wrap 250 having the tear tape 260 which has been pulled across the ream wrap leaving an opening 270 .
[0047] FIG. 8 shows a cross sectional view of the tear tape attached to the ream wrap shown in FIG. 6 . The tear tape 210 is attached to the ream wrap 200 by a heat seal. FIG. 9 shows a cross sectional view of the tear tape shown in FIG. 7 .
[0048] FIG. 10 shows a ream wrap 300 having a tear tape 310 wherein in the ream wrap is closed. FIG. 11 shows a ream wrap 350 having the tear tape 360 which has been pulled across the ream wrap leaving an opening 370 .
[0049] FIG. 12 shows a cross sectional view of the tear tape attached to the ream wrap shown in FIG. 10 . The tear tape 310 is attached to the ream wrap 300 by an adhesive. FIG. 13 is a cross sectional view of the tear tape shown in FIG. 11 .
[0050] FIG. 14 shows an alternate embodiment wherein the ream wrap 400 has a tear tape 410 on top of the ream wrap which opens the top of the ream wrap but keeps the integrity of the ream wrap. FIG. 15 shows the ream wrap of FIG. 14 in the open position.
[0051] FIG. 16 shows an alternate embodiment wherein the ream wrap 500 has a tear tape 510 that does not completely remove a section of the ream wrap. FIG. 17 shows the ream wrap of FIG. 16 in the open position. | Packaging materials that are made from paper, film, or a paper/film combination that have tear tapes made from the same or similar material and applied across the web. The tear tapes may be pulled to tear off and open one end of the packing leaving the remaining packaging intact to serve as a storage and dispenser for the package material. | 1 |
RELATED APPLICATION
[0001] This patent application claims priority to U.S. Provisional Patent Application Ser. No. 62/012,097, entitled “Device For Holding A Firearm” and filed on Jun. 13, 2014, the contents of which are incorporated herein by reference in entirety.
FIELD
[0002] The subject matter described herein relates to a device that holds a firearm in order to prevent damaging the firearm, while still making the firearm be aesthetically appealing, absorb heat generated during a use of the firearm, and reduce kick-back generated by the firearm during use of the firearm.
BACKGROUND
[0003] Firearms are tools that need to be stored so that they are accessible when needed, but without allowing damage to occur to the firearm. Additionally, when in use, it is desirable to have a way of protecting the firearm from damage, such as from friction caused by contact with a stabilizing object, as well as protecting the user from vibration, heat, or other types of irritation caused by the firearm during use.
SUMMARY
[0004] Methods and apparatus are provided for holding a firearm in a manner that insulates a portion of the firearm from its surroundings to prevent the firearm from being damaged, while still making the firearm be aesthetically appealing, absorb heat generated during use of the firearm, and reduce kick-back generated by the firearm during use of the firearm. The apparatus includes an outer portion, an inner portion, and magnets between the outer portion and the inner portion so that the apparatus can hold itself in place on the barrel of a firearm. The apparatus can optionally include a padding layer between the outer portion and the inner portion. The outer portion of the apparatus can be durable and friction resistant. The inner portion of the apparatus can be soft, as well as capable of being used to clean the firearm of debris, gunpowder, dirt, and the like.
[0005] Methods described herein include using the apparatus to store a firearm while protecting the firearm from its surroundings. Methods presented herein can also include using the apparatus to protect the firearm from scratches caused by using the firearm with a support object, such as a stabilizing block. Additionally, or alternatively, the methods can include using the apparatus to clean the outside of the firearm, such as to wipe off lead, gunpowder and its residue, other dirt, or any combination thereof. The methods can also include using the apparatus to mitigate vibration, force, or heat transfer between the firearm and a user, such as when discharging (e.g., firing) the firearm.
[0006] In one aspect, an apparatus is described that can include an outer portion, an inner portion, and at least two magnets between the outer portion and the inner portion. The at least two magnets can hold the outer portion and the inner portion in place on a barrel of a firearm.
[0007] In some variations, one or more of the following can additionally be implemented either individually or in any feasible or suitable combination. The apparatus can further include a padding layer between the outer portion and the inner portion. The outer portion can be configured to resist friction. The outer portion can be made of one or more of: leather, polyurethane, imitation leather, regenerated leather, bonded leather, canvas, coated canvas, suede, heavy cloth, reptile skin, and sheepskin. The inner portion can be configured to be soft. The inner portion can be made of one or more of: cloth, felt, padding, plush material, synthetic material, artificial fur, animal fur, sheepskin, and silk. The inner portion can be configured to be used to clean at least one of debris, gunpowder, and dirt on the barrel of the firearm.
[0008] The apparatus can further include a centerline. The centerline can be aligned with the barrel of the firearm when the firearm is in use and with at least one magnet on each side centerline of the apparatus. The at least two magnets can be made of a same material and have a same shape. A shape of each of the outer portion and the inner portion can be one of elliptical, oval, and circular. A diameter of each of the outer portion and the inner portion can allow each of the outer portion and the inner portion to cover more than half of the barrel of the firearm. In one implementation, the diameter can be 6 inches or more than 6 inches. In another implementation, the diameter can be 6.75 inches or more than 6.75 inches.
[0009] In another aspect, an apparatus can be applied to a barrel of a firearm. The apparatus can include an outer portion, an inner portion, and at least two magnets between the outer and inner portions. The at least two magnets can be configured to hold the outer portion and the inner portion in place on the barrel of the firearm. The firearm with the applied apparatus can be stored in a gun rack.
[0010] In some variations, one or more of the following can additionally be implemented either individually or in any feasible or suitable combination. The gun rack can include one or more depressions configured to store the firearm. The apparatus can further include a padding layer between the outer portion and the inner portion.
[0011] In yet another aspect, an apparatus can be applied to a barrel of a firearm. The apparatus can include an outer portion, an inner portion, and at least two magnets between the outer and inner portions. The at least two magnets can be configured to hold the outer portion and the inner portion in place on the barrel of the firearm. The firearm with the applied apparatus can be placed on a support object.
[0012] In some variations, one or more of the following can additionally be implemented either individually or in any feasible or suitable combination. The firearm can be placed on the support object by overlaying the applied apparatus on the support object. The applied apparatus can minimize transfer of vibration, force, and heat generated, when the firearm is discharged, to a user discharging the firearm. The apparatus can further include a padding layer between the outer portion and the inner portion.
[0013] The above-noted aspects and features may be implemented in systems, apparatuses, methods, and/or articles depending on the desired configuration. The details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the description below. Features and advantages of the subject matter described herein will be apparent from the description and drawings, and from the claims.
p DESCRIPTION OF DRAWINGS
[0014] In the drawings,
[0015] FIG. 1 shows an example of a device for holding a firearm placed around a barrel of a firearm;
[0016] FIG. 2 shows another view of the example of the device for holding a firearm placed around the barrel of the firearm;
[0017] FIG. 3 shows another view of the example of the device for holding a firearm in use;
[0018] FIG. 4 shows an exemplary device for holding a firearm without the firearm in a closed configuration;
[0019] FIG. 5 shows an exemplary device for holding a firearm without the firearm in an open configuration, showing the soft interior of the exemplary device;
[0020] FIG. 6 shows an exemplary device for holding a firearm without the firearm in an open configuration, showing the durable exterior of the exemplary device; and
[0021] FIGS. 7A , 7 B, 8 A, and 8 B show an exemplary device for holding a firearm in a rack.
[0022] Like labels are used to refer to the same or similar items in the drawings.
DETAILED DESCRIPTION
[0023] FIG. 1 shows one view of an exemplary implementation 100 of a device 105 for holding a firearm 110 in use around a barrel of firearm 110 , which is shown as a rifle. The device 105 is shown about the barrel of the firearm 110 , adjacent to the forestock of the firearm. A pair of magnets hold the device to the barrel of the firearm 110 .
[0024] The device 105 can enable maintenance of the firearm 110 in a good condition, both during storage of the firearm 110 and usage of the firearm 110 . The device 105 can protect the firearm 110 when the firearm 110 is being stored in, for example, a gun rack. The device 105 can also protect the firearm 110 when the firearm 110 is in contact with a supporting object (or a supporting substance) or any other object (or substance) that can cause scratches or other marks due to friction between the firearm and its surroundings. The device 105 can also be used to prevent the transfer of force, such as kickback or friction, or temperature, including heat, from the firearm 110 to the user so that discharging (e.g., firing) the firearm is more comfortable. The device 110 can also make the firearm 110 aesthetically appealing (for example, aesthetically pleasing).
[0025] As discussed above, the firearm 110 shown in FIG. 1 is a rifle. This rifle can be one or more of air gun, an automatic rifle, a bolt action, a double rifle, a lever-action rifle, a recoilless rifle, a repeating rifle, a revolving rifle, a semi-automatic rifle, a short-barreled rifle, a spencer rifle, and the like. Although the firearm 110 is described as a rifle, in other implementations, the firearm 110 can be any one of a handgun, a shotgun, a musket, a carbine, and the like.
[0026] FIG. 2 shows another view of the implementation 100 of a device 105 for holding a firearm 110 in use around the barrel of a firearm 110 .
[0027] FIG. 3 shows the exemplary implementation 100 of the device 105 for holding a firearm in a use configuration. The device 105 is wrapped around the barrel of the firearm 110 , as also shown in FIGS. 1 and 2 . The inner 120 and outer 125 portions of the device 105 can be seen. The outer portion 125 of the device is in contact with the surroundings of the firearm 110 . In FIG. 3 , the firearm 110 is shown leaning on the edge of a stabilizing object 115 . The outer portion 125 of the device 105 can contact the edge of the stabilizing object 115 while the inner portion 120 contacts the barrel of the firearm 110 .
[0028] FIG. 4 shows an implementation of a device 105 for holding the firearm 110 . The outside portion 125 of the device 105 is shown, and the device 105 is shown folded along a centerline 440 . The material forming the outside portion 125 can be any suitably durable material, such as one or more of: leather, polyurethane (for example, imitation leather), regenerated leather (for example, bonded leather), canvas, coated canvas, suede, heavy cloth, reptile skin (for example, alligator, snake), sheepskin, and the like. The material forming the outside portion 125 can be suitable for use with a wide temperature range such as −40° C. to +50° C. or more. The material forming the outside portion 125 can also withstand repeated folding, particularly along the centerline 440 of the device. Water and stain resistance can also be characteristics of the material forming the outside portion 125 of the device 105 . In addition, the material forming the outside portion 125 can be suitable for easy cleaning such as in a washing machine.
[0029] FIG. 5 shows an implementation of an open configuration of the device 105 for holding a firearm 110 . The inner portion 120 of the device is shown, and the centerline 440 is identified for easier orientation within the figure. On either side of the centerline 440 , there is a magnet 545 (represented by circles in FIG. 5 and FIG. 6 ) underneath the material of the inner portion 120 . The material of the inner portion 120 can be any suitably soft, easily cleaned material. Some examples of materials for the inner portion 120 of the device 105 include one or more of: cloth, felt, padding, plush material, a synthetic material, artificial fur, animal fur, sheepskin, silk, and the like. Padding material, such as wool, cotton, or synthetic fibers, can be inserted between the inner portion 120 and the outer portion 125 of the device 105 . The material used for the inner portion 120 of the device, alone or in combination with the material of the outside of the device, as well as the padding material, can fold easily, such as along the centerline 440 . In addition, the material forming the inner portion 120 can be suitable for easy cleaning such as in a washing machine.
[0030] The material used for the inner portion 120 can also be used to clean lead, gunpowder, dirt, and the like, from the outside of the firearm 110 . Additionally, the device 105 can be cleaned easily, such as by washing with water, including hand washing or machine washing.
[0031] The magnets 545 can both be of the same material, or each can be of a different material. In some exemplary implementations, one or both of the magnets 545 can be rare-earth magnets or magnets of another ferromagnetic material. The magnets 545 can be any suitable size and shape, such as disk-shaped and approximately 1.5 cm in diameter. The magnets 545 can be held in place in the device 105 with, for example, stitching or adhesive. The location of the magnets 545 can be any location that is convenient for holding the device 105 in place against the barrel of a firearm, such as a set distance away from the centerline 440 or a set distance away from the edge of the device.
[0032] FIG. 6 shows implementation of a device 105 for holding a firearm 110 in an open configuration. Two magnets 545 can be placed in the device 105 , one on either side of the centerline 440 . The outer portion 125 is shown in FIG. 6 .
[0033] From FIGS. 5 and 6 , the overall shape of the device 105 can be seen. The device 105 can be elliptical or oval shaped. Alternatively, the device 105 can be circular, such as disk shaped. Other shapes of the device 105 are also possible, such as a square, a rectangle, a pentagon, a hexagon, any polygon, any irregular shape, of the like. The device 105 can have a diameter that allows the device 105 to cover much of the barrel of an average gun or rifle, such as about 6.25 inches (15.875 cm.), including about 6 inches (15.24 cm), about 6.5 inches (16.51 cm), and about 6.75 inches (17.145 cm). In some embodiments, the device 105 can have a diameter ranging from about 6 inches to about 6.75 inches. The centerline 440 is along the minor axis of the oval or along the diameter of the circle, and the magnets 545 are shown to be a predetermined distance away from the edge of the device 105 , as measured at the major axis of the device 105 in the case of an oval shaped device. In some embodiments, the magnets 545 can be 0.75 inches (1.905 cm) away from the edge of the device 105 . As indicated above, the device 105 can have two layers (for example, the outer portion and the inner portion) or three layers (for example, the outer portion, the inner portion, and a padding layer between the outer portion and the inner portion).
[0034] Both the outer portion 125 and inner portion 120 materials can be any pattern or color, such as a solid color, camouflage, animal print, striped, checked, paisley, argyle, plaid, or any combination thereof.
[0035] FIGS. 7A , 7 B, 8 A, and 8 B show a firearm 110 with a device 105 in use in a rack 750 . The rack 750 can have one or more depressions, each of which is sized to accommodate a firearm 110 by, for example, supporting the barrel of a firearm 110 while one end of the firearm 110 rests on a base of the rack 750 or on the ground. The device 105 is shown fitting around the barrel of the firearm 110 , between the firearm 110 and the rack 750 . When used in this way, the device 105 can prevent scratches from appearing on the firearm 105 when the firearm 110 is placed in and removed from the rack 750 . Also, a firearm 105 that may be elevated in temperature can be placed into the rack 750 without concern that heat from the firearm could cause an adverse interaction between the firearm 110 and the rack 750 , more specifically between the barrel of the firearm 110 and the paint on the rack 750 .
[0036] Although the device 105 is described as including one or more magnets to hold the firearm 110 , in other implementations, the device 105 can include any suitable mechanism to allow for reversible attachment of the device 105 to the firearm 110 . Some examples of such suitable mechanisms can include one or more of: straps with hook and loop closures (for example, Velcro®), grommets and laces, ties, snaps, buttons, buckles, hooks, adhesive, tape, bands (for example, rubber bands, metal bands), and the like.
[0037] Although a few variations have been described in detail above, other modifications or additions are possible. In particular, further features and/or variations may be provided in addition to those set forth herein. For example, the implementations described above may be directed to various combinations and subcombinations of the disclosed features and/or combinations and subcombinations of several further features disclosed above. In addition, the logic flow depicted in the accompanying figures and/or described herein does not require the particular order shown, or sequential order, to achieve desirable results. The phrases “based on” and “based on at least” are used interchangeably herein. Other implementations may be within the scope of the following claims. | A device that can hold a firearm can be used to prevent the firearm from being damaged, make the firearm aesthetically appealing, absorb the heat generated during use of the firearm, and reduce kick-back generated by the firearm. The device can include an inner portion, an outer portion, and magnets between the inner portion and the outer portion. The outer portion of the device can be made of a friction resistant material, which enhances durability to endure contact with items such as a gun rack or a stabilizing object. The inner portion of the device can be made of a soft material that can be used to cushion the firearm, and optionally clean the firearm. Related methods and products are also described. | 5 |
REFERENCE TO A SEQUENCE LISTING SUBMITTED ELECTRONICALLY VIA EFS-WEB
[0001] The content of the electronically submitted sequence listing, file name: 2511 — 0120002_SEQ_ID_Listing.ascii.txt; size: 95,695 bytes; and date of creation: Sep. 14, 2012, filed herewith, is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention provides avirulent Salmonella variants and various uses thereof, particularly in the production of Salmonella -specific lytic bacteriophages, pharmaceutical compositions, and feed additives.
[0004] 2. Description of the Related Art
[0005] Currently over 2,000 Salmonella strains are generally classified into host-specific serotypes, and non-host-specific serotypes pathogenic for both animals and humans. Representative among fowl-adapted pathogens are Salmonella Gallinarum (SG) and Salmonella Pullorum (SP) which are known to cause fowl typhoid and pullorum disease, respectively. These Salmonella -caused fowl diseases occur at low frequency in advanced countries, but have inflicted tremendous economic damage on the poultry farming in developing countries.
[0006] Salmonella Gallinarum strains have serologically the same somatic antigen (O-antigen) structures and are classified as being non-motile because they have no flagella. When entering into a host animal via contaminated feed or a contaminated environment, Salmonella pass through the gastrointestinal tract, and invade intestinal epithelial cells by interaction with Peyer's patch M (microfold) cells and penetrate into the intestinal membrane. Salmonella are transported by the M cells to macrophages in adjacent intestinal membranes, and then Salmonella infection develops into a systemic disease.
[0007] The type III secretion system (TTSS) is a protein appendage found in Gram-negative bacteria, which consists of a needle-like protein complex structure through which virulence effector proteins pass from the bacterial cytoplasm directly into the host cytoplasm (Mota L J et al., Ann Med. (2005);37(4):234-249). The type III secretion system is essential for the delivery of the pathogenicity of Salmonella (Schlumberger M C et al., Curr Opin Microbiol. (2006);9(1):46-54). Wild-type Salmonella take advantage of TTSS when adhering to and invading host cells, and then survives during the phagocytosis of macrophages and circulates throughout the body via the bloodstream, causing a systemic infection. Hence, Salmonella infection cannot proceed without the normal operation of TTSS. Salmonella pathogenicity island-1 (hereinafter referred to as “SPI-1”) is a discrete region of the Salmonella chromosome encoding the type III secretion system and virulent effector proteins which are necessary for invasion into intestinal epithelial cells in the early stage of infection (Kimbrough T G et al., Microbes Infect, (2002);4(1):75-82). Salmonella pathogenicity island-2 (hereinafter referred to as “SPI-2”) is also a discrete region of the Salmonella chromosome encoding the type III secretion system and effector proteins which involved in survival and proliferation during phagocytosis by macrophages in intestinal immune organs or immune organs such as the spleen and the liver after translocation across epithelial cells (Waterman S R et al., Cell Microbiol, (2003);5(8):501˜511, Abrahams G L, Cell Microbiol, (2006);8(5):728-737). Genes within SPI-1 and SPI-2 and their functions are summarized in Table 1, below.
[0000]
TABLE 1
Gene
Characteristics
SPI-1
avrA
putative inner membrane protein
sprB
transcriptional regulator
hilC
bacterial regulatory helix-turn-helix
proteins, araC family
orgA
putative flagellar biosynthesis/type
III secretory pathway protein
prgK
cell invasion protein; lipoprotein,
may link inner and outer membranes
prgJIH
cell invasion protein
hilD
regulatory helix-turn-helix proteins,
araC family
hilA
invasion genes transcription activator
iagB
cell invasion protein
sptP
protein tyrosine phosphate
sicP
chaperone, related to virulence
iacP
putative acyl carrier protein
sipADCB
cell invasion protein
sicA
surface presentation of antigens;
secretory proteins
spaSRQPO
surface presentation of antigens;
secretory proteins
invJICB
surface presentation of antigens;
secretory proteins
invAEGFH
invasion protein
SPI-2
ssaUTSRQPON
Secretion system apparatus
VMLKJIHG
sseGF
Secretion system effector
sscB
Secretion system chaperone
sseEDC
Secretion system effector
sscA
Secretion system chaperone
sseBA
Secretion system effector
ssaE
Secretion system effector
ssaDCB
Secretion system apparatus
ssrA
Secretion system regulator: Sensor
component
ssrB
Secretion system regulator:
transcriptional activator, homologous
with degU/uvrY/bvgA
[0008] In addition to these type III secretion systems, fimbriae gene (faeHI) (Edwards R A et al., PNAS (2000); 97 (3):1258-1262) and the virulent factor (spvRABCD operon) present in virulent plasmids of Salmonella are implicated in the virulence of Salmonella (Gulig P A et al., Mol Microbiol (1993);7(6):825-830).
[0009] Salmonella -caused fowl diseases are difficult to control because they are transmitted in various ways including egg transmission, and feed or environmental infection, and show high recurrence rates even after post-infectious treatment with antibiotics. Therefore, it is importance of preventing the onset of disease by using a vaccine as well as sanitizing breeding farms and feed. In the poultry industry, a lot of effort has been poured into the use of live vaccines (attenuated Salmonella Gallinarum strains—SG9S, SG9R) and dead vaccines (gel vaccines, oil vaccines, etc.) to prevent the onset of fowl typhoid. However, the effects of the vaccine vary with the concentration of the vaccine used, the condition of the fowl vaccinated, and the environment of chicken houses. And, the efficacy of these vaccines is reported to be significantly lower than that of the vaccines for other diseases. Treatment with antibiotics, although reducing the lesion, converts infected fowls into chronic carriers (See: Incidence and Prevention of Hen Salmonellosis, the National Veterinary Research & Quarantine Service, Korea).
[0010] Therefore, new Salmonella -controlling approaches that are better than conventional vaccines or antibiotics are being demanded. Many scientists have recently paid attention to bacteriophages, which infect and lyse bacteria specifically and are safe to humans, as a potent alternative to antibiotics. There are many reports concerning the use of bacteriophages being used in the prevention or therapy of Salmonella diseases (Atterbury R J et al., Appl Environ Microbiol, (2007); 73 (14):4543-4549) and as disinfectants or detergents to prevent the putrefaction of foods (PCT 1998-08944, PCT 1995-31562, EP 1990-202169, PCT 1990-03122), and concerning phage display techniques for diagnosis (Ripp S et al., J Appl Microbiol, (2006);100(3):488-499), Salmonella vaccines prepared by deleting or modifying one or two genes within SPI-2 gene cluster have recently been disclosed (U.S. Pat. No. 6,923,957, U.S. Pat. No. 7,211,264, U.S. Pat. No. 7,887,816).
[0011] For industrial use, bacteriophages are produced by separating the phage progenies from the host cells lysed during the proliferation of bacteriophages which have been inoculated into the host cells cultured on a mass scale. As for bacteriophages specific for pathogenic bacteria, however, their lysates may contain the pathogenic host cells being not removed, and/or virulent materials such as pathogenic proteins of the host. This likelihood acts as a great risk factor to the safety of bacteriophages produced on the basis of pathogenic host cells.
[0012] Many bacteria have lysogenic phages on their chromosomes; however, most of the phages are cryptic and cannot produce progeny because of the accumulation of many mutations as ancestral remnants. Lysogenic phages, although inactive, may help the survival capacity of Salmonella upon host infection because they contain the genes necessary for lytic and lysogenic growth and some of the genes encode pathogenic factors. However, these genes are likely to undergo homologous recombination with the viral genome of other similar phages which newly infect animals, thus producing genetically modified phages. As for the typical Salmonella typhimurium , it has fels-1, fels-2, gifsy-1, and gifsy-2 prophages and two cryptic phages. In contrast, Salmonella Gallinarum could be used as a phage-producing host since Salmonella Gallinarum have neither prophages nor cryptic phages, and then are not genetically modified by recombination, (Edwards P A et al, Trends Microbiol, (2002); 10(2):94-99).
[0013] For the purpose of minimizing toxic remnants during progeny production and phage's opportunity for mutation, the present inventors designed the idea that the virulence gene clusters of Salmonella Gallinarum could be inactivated for producing bacteriophages. There have no precedent cases wherein avirulent bacteria, which had been converted from virulent bacteria by inactivating a virulence gene cluster, were used as a bacteriophage host cell.
[0014] In addition to the production of bacteriophages, the Salmonella deprived of virulence by inactivating virulence gene clusters are themselves used for developing attenuated live vaccines for controlling Salmonella or applied to the bioindustry, guaranteeing significant added values.
[0015] In the present invention, avirulent Salmonella Gallinarum variants obtained by inactivating at least one of the main Salmonella virulence gene clusters (SPI-1, SPI-2, spvRABCD and faeHI operons) are used as a bacteriophage-producing host cell and applied to various uses.
SUMMARY OF THE INVENTION
[0016] With the aim of solving the problems with the recombinational modification of progeny phages and the toxic bacterial remnants in the course of bacteriophage production on the basis of the above-described facts, the present inventors developed avirulent Salmonella Gallinarum variants as a host cell for bacteriophage-producing by inactivating at least one of the four main Salmonella . Gallinarum gene clusters (SPI-1, SPI-2, spvRABCD and faeHI operons). In addition, the present inventors primarily confirmed reduced virulence by measuring the efficiency of the invasion of Salmonella Gallinarum into avian epithelial cells, and reconfirmed by measuring the mortality of hens infected with avirulent Salmonella Gallinarum variants. On the other hand, the present inventors approve the use of bacteriophage-producing host, the use of the pharmaceutical compositions and feed additives for the prevention or treatment of avian salmonellosis through comparison of the productivity of bacteriophages between wild-type and the avirulent Salmonella Gallinarum variants.
[0017] It is therefore a primary object of the present invention to provide a Salmonella Gallinarum variant in which the SPI-2 gene cluster is inactivated, a Salmonella Gallinarum variant in which both SPI-1 and SPI-2 gene clusters are inactivated, and an avirulent Salmonella Gallinarum variant in which at least one of the four main virulence gene clusters (SPI-1, SPI-2, spvRABCD, and faeHI operon) has been inactivated.
[0018] It is another object of the present invention to provide the use of the avirulent Salmonella Gallinarum variant in the production of Salmonella -specific bacteriophages or a method for producing phages using the avirulent Salmonella Gallinarum variant. The avirulent Salmonella Gallinarum variants according to the present invention can be used for the mass-production of Salmonella -specific lytic bacteriophages free of remnant toxicity and applied to the development of a novel concept of antibiotic substitutes which have high industrial utility value and guarantee significant added value.
[0019] It is a further object of the present invention to provide a pharmaceutical composition comprising avirulent Salmonella Gallinarum variants as an active ingredient, preferably a live vaccine and a feed additive. The SPI-1 gene cluster encodes type III secretion system proteins which remain on cell surfaces, acting as an antigen while the SPI-2 gene cluster encodes proteins which are involved in survival in the phagosomes after passage across epithelial cells. Hence, the inactivation of the SPI-2 gene cluster alone, with SPI-1 gene cluster remaining intact, leaves the antigen necessary for the production of an antibody inducing an immune response, but does not allow the bacteria to survive during phagocytosis, which does not result in a systemic disease. Thus, the SPI-2 gene cluster-inactivated Salmonella Gallinarum variant might be used as a live vaccine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0021] FIG. 1 is a schematic diagram showing virulence genes of avian Salmonella (Salmonella pathogenicity island-1, Salmonella pathogenicity island-2, spvRABCD, faeHI) and sites corresponding to primers for inactivating the virulence genes; and
[0022] FIG. 2 is a graph showing the efficiency of the in vitro invasion into avian epithelial cells of the virulence gene-inactivated Salmonella Gallinarum variants (SG3-d1, SG3-d2, SG3-d1d2, SG3-d4), together with controls wild-type Salmonella Gallinarum SG2293), Salmonella Gallinarum live vaccine (SG9R), and non-pathogenic E. coli (MG1655). Invasion efficiency is expressed as a percentage of the count of microorganisms within cells divided with the count of microorganisms within a culture medium. The microorganisms were used at a concentration of 8.0×10 7 cfu per well.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] In order to accomplish the above objects, an aspect of the present invention provides the avirulent Salmonella Gallinarum variants which are remarkably decreased in pathogenicity.
[0024] The Salmonella Gallinarum variants are rendered avirulent by inactivating at least one of the virulence gene clusters Salmonella pathogenicity island-1, Salmonella Pathogenicity Island-2, spvRABCDf and faeHI.
[0025] As used herein, the term “virulence gene clusters of Salmonella ” refers to the four gene clusters involved in the virulence of Salmonella Gallinarum , including the Salmonella Pathogenicity Island-1 (hereinafter referred to as “SPI-1”) operon coding for the structural proteins and toxic effector proteins of type III secretion system, the Salmonella Pathogenicity Island-2 (hereinafter referred to as “SPI-2”) operon coding for the structural proteins and toxic effector proteins of type III secretion system, the spvRABCD operon coding for pathogenically active proteins on avian Salmonella -specific virulent plasmids, and the faeHI operon coding for fimbriae. So long as it functionally works in Salmonella Gallinarum , any gene cluster may be used.
[0026] The term “gene cluster,” as used herein, refers to a population of adjacent genes on a chromosome or a plasmid that are commonly responsible for the same products. The genes in one cluster are under the regulation of common regulatory genes.
[0027] The inactivation of genes in bacteria can be achieved using various methods. For example, single or multiple nucleotides of an active site within a gene may be modified to decrease the activity of the protein expressed. Alternatively, an antibiotic-resistant gene or other gene(s) may be inserted into the gene of interest to prevent the expression of intact proteins. The most reliable method is to delete the entire sequence of a gene from the genome (Russell C B et al., J. Bacteriol. (1989); 171:2609-2613, Hamilton C M et al., J. Bacteriol. (1989); 171:4617-4622, Link A J et al., J. Bacteriol. (1997); 179:6228-6237). In the present invention, entire sequences of the genes of interest are deleted to effectively promise the inactivation of the genes. For this, the one-step deletion method using lambda Red recombinase, known as a method of deleting gene clusters, developed by Datsenk K A et al., may be employed (Datsenko K A et al., PNAS, (2000); 97 (12):6640-6645).
[0028] With regard to the information of virulence genes to be deleted, nucleotide sequences of SPI-1 and SPI-2 were, obtained referring to the virulence gene sequences within the Salmonella Gallinarum chromosome ( Salmonella enterica subsp. enterica serovar Gallinarum str. 287/91, NC 011274), disclosed by the NCBI. For the faeHI operon sequence, reference was made to the sequence of the Salmonella Gallinarum virulence plasmid gene ( Salmonella Gallinarum virulence plasmid minor fimbrial subunit genes, AF005899). For the spvRABCD operon, the sequence of the same name gene of Salmonella Typhimurium LT2, which has highly homology with Salmonella Gallinarum , was consulted because its sequence is not disclosed in the NCBI. The sequencing of the spvRABCD operon of Salmonella Gallinarum was also performed with reference to the sequence of the corresponding gene of Salmonella Typhimurium.
[0029] Examples of the Salmonella virulence genes clusters include the SPI-1 gene cluster (SEQ ID NO: 1), the SPI-2 (SEQ ID NO: 2), the spvRABCD operon (SEQ ID NO: 3), and the faeHI operon (SEQ ID NO: 4) of Salmonella Gallinarum 287/91.
[0030] To prepare strains that, had definitely been rendered avirulent, all of the plural virulence gene clusters were deleted. To inactivate many gene clusters in one strain, the gene clusters may have been deleted sequentially.
[0031] In the present invention, a Salmonella Gallinarum strain in which only the SPI-2 gene cluster is inactivated (SG3-d2), a Salmonella Gallinarum strain in which both SPI-1 and SPI-2 gene clusters are integrally inactivated (SG3-d1d2) and a Salmonella Gallinarum strain in which all of the four virulence gene clusters (SPI-1, SPI-2, spvRABCD, faeHI) are integrally inactivated (SG3-d4). SG3-d2 is deposited under accession No. KCCM 11009P, SG3-d1d2 under accession No. KCCM 11010P, and SG3-d4 under accession No. KCCM 11011P.
[0032] Studies on the independent deletion of individual genes of the gene clusters have been reported (Hapfelmeier S et al., J Immunol, (2005); 174(3): 1675-1685, Brumme S et al., Vet Microbiol, (2007); 124(3-4):274-285, Desin T S et al., Infect Immun, July (2009); 2866-2875), but avirulent Salmonella strains developed by integrally inactivating two or more entire gene clusters had not been disclosed prior to the study of the present inventors. The Salmonella Gallinarum strain was named Salmonella Gallinarum SG2293-d2 when only the SPI-2 gene cluster is inactivated, and SG2293-d1d2 when both SPI-1 and SPI-2 were integrally inactivated. Further, it was named SG2293-d4 upon the inactivation of all of SPI-1, SPI-2, spvRABCD, and faeHI.
[0033] To ascertain the avirulence thereof, the strains prepared by inactivating virulence gene clusters according to the present invention were assayed for the efficiency of invasion into avian epithelial cells and for disease outbreak and mortality (%) upon infection into poultry. Preferably, the Salmonella Gallinarum strains in which the virulence gene clusters had been inactivated by transformation were allowed to invade avian epithelial cells so that invasion efficiency could be measured. Also, the strains were injected into brown egg layers to measure mortality.
[0034] In accordance with another aspect thereof, the present invention provides an avirulent Salmonella , strain for use in producing Salmonella -specific lytic bacteriophages and a method for producing phages using the same.
[0035] ΦCJ1 (US 20100135962), a Salmonella -specific phage, was used to examine the bacteriophage productivity of the avirulent Salmonella Gallinarum variants. The phage shows a specific bactericidal activity against Salmonella Gallinarum and Salmonella pullorum , belongs to the morphotype group of the family Siphoviridae B1, characterised by isometric capsid and long non-contractile tail, and has a total genome size of 61 kb and major structural proteins with a size of 38 kDa and 49 kDa.
[0036] The method for producing a bacteriophage in accordance with the present invention comprises culturing the avirulent Salmonella Gallinarum variants in a medium, inoculating a bacteriophage into the medium, and recovering the bacteriophage. In this regard, the phage may be produced briefly using a plate or on a mass scale using broth. In the case of production using a plate, a bacteriophage is inoculated at a suitable ratio into bacteria when the bacteria enter a log phase, mixed with top agar, and poured onto a plate. When phage plaques appear, the top agar fractions are collected and centrifuged, followed by filtering the supernatant to afford a phage stock. For mass production as a broth, a mixture of phages and bacteria is prepared in the same manner as in plate production, and incubated for 5 hours in fresh broth, instead of in top agar.
[0037] In accordance with a further aspect thereof, the present invention provides a pharmaceutical composition for the prevention of fowl typhoid, comprising the avirulent Salmonella , strain as an active ingredient and optionally a pharmaceutically acceptable vehicle, and preferably a vaccine for the prevention of fowl typhoid, formulated with the avirulent Salmonella strain and optionally a pharmaceutically acceptable vehicle.
[0038] The term “pharmaceutically acceptable vehicle,” as used herein, refers to a carrier or diluent which does not deteriorate the biological activity and property of the active ingredient and which does not irritate the subject. Preparations intended for oral administration may take the form of tablets, troches, lozenges, aqueous or oily suspensions, powders, granules, emulsions, hard or soft capsules, syrups, elixirs, etc. In regards to the oral forms such as tablets and capsules, the active ingredient may be formulated in combination with a binder such as lactose, saccharose, sorbitol, mannitol, starch, amylpectin, conjugate such as cellulose or gelatin, an excipient such as dicalcium phosphate, a disintegrant such as corn starch or sweet potato starch, or a lubricant such as magnesium stearate, calcium stearate, sodium stearylfumarate or polyethylene glycol wax. As for capsules, they may further comprise a liquid carrier such as fatty oil.
[0039] The composition of the present invention may be formulated into preparations for non-oral administration, such as subcutaneous injections, intravenous injections, or intradermal injections. For this, the composition of the present invention may be mixed with a stabilizer or buffer in water to give a solution or a suspension which is then formulated into unit doses such as ampules or vials.
[0040] As used herein, the term “vaccine” refers to a biological preparation that improves immunity to a particular disease by inducing the formation of an antibody upon injection into the body, a preparation containing an antigen, e.g., killed or attenuated forms of a disease-causing microorganism. Vaccines may be prepared from killed pathogens. There are also live vaccines, but with the virulence thereof attenuated. The Salmonella Gallinarum variants of the present invention have the same antigenic proteins as those of the wild-type, but are greatly decreased in virulence compared to the wild-type, so that they can be used as live vaccines prophylactic of fowl typhoid.
[0041] In accordance with still another aspect thereof, the present invention provides a feedstuff containing the avirulent Salmonella Gallinarum , and preferably a feed additive containing the avirulent Salmonella Gallinarum . When applied to poultry, the feed additive of the present invention serves as a live vaccine that prevents fowl typhoid.
[0042] The feedstuff of the present invention may foe prepared by mixing feedstuff with the Salmonella Gallinarum variant as it is or in the form of a feed additive. In the feedstuff, the Salmonella Gallinarum variant may be in a liquid or dry state. The dry state can be accomplished by various drying methods including, but not limited thereto, pneumatic drying, spontaneous drying, spray drying and freeze drying. In addition to the Salmonella Gallinarum variant of the present invention, the feedstuff of the present invention may further comprise a typical additive useful for improving the preservation of the feedstuff.
[0043] The feedstuff comprising the Salmonella Gallinarum variant of the present invention may be vegetable matter such as a cereal, nut, a by-product of food processing, millet, fiber, pharmaceutical by-product, a vegetable oil, starch, oil seed meals and cereal remnants, or animal matter such as proteins, minerals, fats, mineral oils, unicellular proteins, animal planktons and leftover food etc.
[0044] Examples of the feed additive comprising the Salmonella Gallinarum variant of the present invention include, but are not limited to, various agents for preventing quality deterioration and improving utility, such as binders, emulsifiers, preservatives, amino acids, vitamins, enzymes, probiotics, flavoring agents, non-protein nitrogen compounds, silicates, buffer, colorants, extracts, oligosaccharides, etc. Also, a mixing agent may be within the scope of the feed additive.
[0045] In accordance with still a further aspect thereof, the present invention provides a method for treating the Salmonella Gallinarum infectious disease fowl typhoid using the pharmaceutical composition.
[0046] The composition of the present invention may be administered to animals in the form of a pharmaceutical preparation to animals, or in the form of being mixed with feedstuff or water. Preferably, it is mixed in the form of a feed additive with feedstuff before administration.
[0047] So long as it allows the composition of the present invention to reach tissues or cells of interest, any administration route, such as non-oral, intraartery, intradermal, transdermal, intramuscular, intraperitoneal, intravenous, subcutaneous, oral or intranasal route, may be taken.
[0048] The treating method of the present invention comprises administering the composition of the present invention in a pharmaceutically effective amount. It will be apparent to those skilled in the art that the suitable, total daily dose may be determined by an attending physician within the scope of medical judgment. The specific therapeutically effective dose level for any particular patient may vary depending on a variety of factors, including the kind and degree of desired reaction, the specific composition, including the use of any other agents according to the intended use, the patient's age, weight, general health, gender, and diet, the time of administration, the route of administration, and rate of the excretion of the composition; the duration of the treatment; other drugs used in combination or coincidentally with the specific composition; and like factors well known in the medical arts. Typically, the composition may be administered at a daily dose of from 10 4 to 10 8 CFU once or in a divided dosage manner.
[0049] Hereinafter, the present invention will be described in more retail with reference to Examples. However, these Examples are for illustrative purposes only, and the invention is not intended to be limited by these Examples.
Example 1
Screening of Target Genes to be Inactivated through Comparison of Salmonella Gallinarum Virulence Genes
[0050] The first step of preparing avirulent avian Salmonella strains was the screening of target virulence genes to be inactivated. Salmonella Pathogenicity Island-1 (SPI-1), and Salmonella Pathogenicity Island-2 (SPI-2), both of which are type three secretion system gene clusters essential for the delivery of the pathogenicity of Salmonella , and spvRABCD and faeHI, both of which are genes on virulence plasmids, were determined as target genes, and the data base of the NCBI was searched for the nucleotide sequences of the target genes ( Salmonella enterica subsp. enterica serovar Gallinarum str. 287/91, NC 011274). Because the nucleotide sequence of spvRABCD of Salmonella Gallinarum had not yet been disclosed, primers were synthesized with reference to the nucleotide sequence of the same name gene of Salmonella typhimurium ( Salmonella typhimurium LT2 plasmid pSLT, NC 003277), which has high nucleotide sequence homology with Salmonella Gallinarum . As for the faeHI operon, the information of its nucleotide sequence was obtained from Salmonella Gallinarum virulence plasmid minor fimbrial subunit genes (AF005899).
Example 2
Preparation of Avirulent Variants by Inactivation of Virulence Genes of Salmonella Gallinarum and by Integration of the Inactivated Sites
[0051] 2-1. Inactivation of Virulence Genes of Salmonella Gallinarum
[0052] To delete TTSS-related virulence genes of the wild-type Salmonella Gallinarum (SGSC No. 2293) as determined in Example 1, the one-step deletion method using lambda Red recombinase, developed by Datsenko K A et al., (Datsenko K A et al, PNAS, (2000); 97(12):6640-6645), was employed.
[0053] A chloramphenicol resistant gene of pKD3 was used as an antibiotic marker for identifying insertion into a target site of chromosome. Using a pair of the primers SPI-1-P1 (SEQ ID NO: 5) and SPI-1-P2 (SEQ ID NO: 6) of Table 1, which correspond to 50 bp of 5′ flanking region of the avrA and 50 bp of 3′ flanking region of the invH gene, wherein SPI-1 comprising from avrA to invH is target for deletion, and a part of the chloramphenicol resistant gene of pKD3, respectively, a polymerase chain reaction (hereinafter referred to as “PCR”) was performed [Sambrook et al, Molecular Cloning, a Laboratory Manual (1989), Cold Spring Harbor Laboratories], with pKD3 as a template. The obtained PCR product was gene fragment about 1100 bp long.
[0054] In this regard, a PCR EL premix kit (BIONEER) was used and 30 cycles of denaturation at 94° C. for 30 sec, annealing at 55 ° C. for 30 sec and elongation at 72° C. for 1 min was conducted. The PCR product was separated in 0.8% agarose gel by electrophoresis and eluted at a desired band size.
[0055] According to the method of Datsenko K A et al., the 1100 bp-long gene fragment was introduced into pKD46-transformed, competent wild-type Salmonella Gallinarum , which was then spread over LB plates containing chloramphenicol (30 mg/L), As for the resulting transformant, its gene was examined by PCR using a pair of the primers SPI-1-P3 (SEQ ID NO: 7) and SPI-1-P4 (SEQ ID NO: 8), which correspond to regions about 1 kb distant from both ends of the deletion target gene, respectively. The PCR product thus obtained was 3100 bp long, indicating that the SPI-1 gene cluster was inactivated.
[0056] The resulting strain was cultured at 37° C., a condition of removing the pKD46 vector, to select a strain that could not grow on an LB plate containing ampicillin (100 mg/L).
[0057] Subsequently, the antibiotic marker inserted into the inactivated gene cluster was removed by transformation with pCP20. The removal of the antibiotic marker was identified by PCR using the primers SPI-1-P3 & SPI-1-P4. The resulting PCR product was 2000 bp long, also indicating the inactivation.
[0058] Afterwards, the strain which was now free of the antibiotic marker was cultured at 42° C. (a condition of removing pCP20) to select a strain that could not grow on an LB plate containing ampicillin. The SPI-1 gene cluster-inactivated strain thus obtained was named SG3-d1 ( Salmonella Gallinarum SG2293::ΔSPI-1).
[0059] SPI-2, spv, and fae gene clusters were also inactivated in the same manner as in the SPI-1 gene cluster. The resulting gene cluster-inactivated strains were named SG3-d2 ( Salmonella Gallinarum SG2293::ΔSPI-2, Accession No. KCCM 11009P), SG3-ds ( Salmonella Gallinarum SG2293::Δspv), and SG3-df ( Salmonella Gallinarum SG2293::Δfae), respectively. Primers used for deleting genes and for identifying gene deletion are summarized in Table 2, below.
[0000]
TABLE 2
Primers for deletion of SPI-1 gene from
chromosome
SPI-1-P1
TTATGGCGCTGGAAGGATTTCCTCTGGCAGGCAACCT
(SEQ ID
TATAATTTCATTAGTGTAGGCTGGAGCTGCTTC
NO: 5)
SPI-1-P2
ATGCAAAATATGGTCTTAATTATATCATGATGAGTTC
(SEQ ID
AGCCAACGGTGATCATATGAATATCCTCCTTAG
NO: 6)
Primers for Deletion of SPI-2 Gene from
Chromosome
SPI-2-P1
ACCCTCTTAACCTTCGCAGTGGCCTGAAGAAGCATAC
(SEQ ID
CAAAAGCATTTATGTGTAGGCTGGAGCTGCTTC
NO: 9)
SPI-2-P2
ACTGCGTGGCGTAAGGCTCATCAAAATATGACCAATG
(SEQ ID
CTTAATACCATCGCATATGAATATCCTCCTTAG
NO: 10)
Primers for Deletion of spvRABCD gene from
virulence plasmid
spv-P1
GTGCAAAAACAGGTCACCGCCATCCTGTTTTTGCACA
(SEQ ID
TCAAA ACATTTTTGTGTAGGCTGGAGCTGCTTC
NO: 13)
spv-P2
TTACCCCAACAGCTTGCCGTGTTTGCGCTTGAACATA
(SEQ ID
GGGAT GCGGGCTTCATATGAATATCCTCCTTAG
NO: 14)
Primers for Deletion of faeHI gene from
virulence plasmid
fae-P1
TTACCGATATTCAATGCTCACCGCCAGGGAGGTATGC
(SEQ ID
CAGCG GGACGGTAGTGTAGGCTGGAGCTGCTT C
NO: 17)
fae-P2
ATGAAAATAACGCATCATTATAAATCTATTATTTCCG
(SEQ ID
CC CTGGCCGCGCTCATATGAATATCCTCCTTAG
NO: 18)
Primers for identificaion of SPI-1 gene
deletion from chromosome
SPI-1-P3
ATGTTCTTAACAACGTTACTG
(SEQ ID
NO: 7)
SPI-1-P4
AGGTAGTACGTTACTGACCAC
(SEQ ID
NO: 8)
Primers for identification of SPI-2 gene
deletion from chromosome
SPI-2-P3
TGTTCGTACTGCCGATGTCGC
(SEQ ID
NO: 11)
SPI-2-P4
AGTACGACGACTGACGCCAAT
(SEQ ID
NO: 12)
Primers for spvRABCD gene deletion from
virulence plasmid
spv-P3
GACCATATCTGCCTGCCTCAG
(SEQ ID
NO: 15)
spv-P4
CAGAGCCCGTTCTCTACCGAC
(SEQ ID
NO: 16)
Primers for faeHI gene deletion from
virulence plasmid
fae-P3
CAGGCTCCCCTGCCACCGGCT
(SEQ ID
NO: 19)
fae-P4
CAGGCCAACTATCTTTCCCTA
(SEQ ID
NO: 20)
[0060] 2-2. Integration of Type III Secretion System-Related Virulence Genes Inactivation
[0061] To integrally inactivate the gene clusters in one strain, the SG3d1 strain was sequentially subjected to the inactivation of SPI-2, spvRABCD, and faeHI gene clusters, using a method similar to that of Example 2-1.
[0062] To begin with, PCR was performed using the primers SPI-2-P1 (SEQ ID NO: 9) and SPI-2-P2 (SEQ ID NO.: 10) for the purpose of inactivating the SPI-2 cluster gene, with pKD4 serving as a template, resulting a 1600 bp gene fragment. This PCR product was introduced into the SG3-d1 strain in which pKD46 vector retrained (Example 1-2), followed by spreading the bacteria over an LB plate containing kanamycin (50 mg/L). As for the resulting transformant, its gene was examined by PCR using a pair of the primers SPI-2-P3 (SEQ ID NO: 11) and SPI-2-P4 (SEQ ID NO: 12), which correspond to both flanking regions of the deletion target gene. The PCR product thus obtained was 3600 bp long, indicating that the SPI-2 gene cluster was inactivated.
[0063] The resulting strain was cultured at 37° C., a condition of removing the pKD46 vector, to select a strain that could not grow on an LB plate containing ampicillin (100 mg/L).
[0064] Subsequently, the antibiotic marker inserted into the inactivated gene cluster was removed by transformation with pCP20. The removal of the antibiotic marker was identified by PCR using the primers SPI-1-P3 & SPI-1-P4 in case of SPI-1 and the primers SPI-2-P3 & SPI-2-P4 in case of SPI-2. The resulting PCR product was 2000 bp long, also indicating that the inactivation had taken place.
[0065] Afterwards, the strain free of the antibiotic marker was cultured at 42° C. (a condition of removing pCP20) to select a strain that could not grow on an LB plate containing ampicillin. The SPI-1 and SPI-2 gene cluster-inactivated strain thus obtained was named SG3-d1d2 ( Salmonella Gallinarum SG2293::ΔSPI-1ΔSPI-2, Accession No. KCCM 11010P).
[0066] In SG-d1d2 strain, spvRABCD and faeHI gene clusters were further inactivated. To this end, the spvRABCD gene cluster (the kanamycin-resistant gene of pKD4 was used as an antibiotic marker) was inactivated in the same manner as in the inactivation of SPI-1 in Example 1-2, while the inactivation of the faeHI gene cluster (the chloramphenicol-resistant gene of pKD3 was used as an antibiotic marker) was conducted in the same manner as in the inactivation of SPI-2 in the SPI-1-inactivated strain. As for the resulting transformants, their genes were examined by PCR using the primer set spv-P3 (SEQ ID NO: 15) and spv-P4 (SEQ ID NO: 16) for spvRABCD deletion, and the primer set fae-P3 (SEQ ID NO: 19) and fae-P4 (SEQ ID NO: 20) for faeHI deletion, which correspond to regions about 1 kb distant from both ends of the respective deletion target genes. The PCR products thus obtained were 3600 bp, 3100 bp long respectively, indicating that the spvRABCD and faeHI gene clusters were inactivated. The resulting strain was cultured at 37° C., a condition of removing the pKD46 vector, to select a strain that could not grow on an LB plate containing ampicillin (100 mg/L). The Salmonella Gallinarum strain in which all of the four gene clusters SPI-1, SPI-2, spvRABCD and faeHI were integrally inactivated was named SG3-d4 ( Salmonella Gallinarum SG2293:: ΔSPI-1ΔSPI-2ΔspvRABCDΔfaeHI) and deposited under accession No. KCCM 11011P.
[0067] 2-3. Sequencing of Salmonella Gallinarum spvRABCD Operon
[0068] Nowhere has the genetic information on spvRABCD of Salmonella Gallinarum (SGSC No. 2293) been disclosed yet. Its nucleotide sequence was analyzed in the present invention. For this, primers were synthesized as summarized in Table 3, below.
[0000]
TABLE 3
spv-S1
GGTCAATTAAATCCACTCAGAA
(SEQ ID NO: 21)
spv-S2
ACGGGAGACACCAGATTATC
(SEQ ID NO: 22)
spv-S3
TTCAGTAAAGTGGCGTGAGC
(SEQ ID NO: 23)
spv-S4
CCAGGTGGAGTTATCTCTGC
(SEQ ID NO: 24)
spv-S5
ACTGTCGGGCAAAGGTATTC
(SEQ ID NO: 25)
spv-S6
TTTCTGGTTACTGCATGACAG
(SEQ ID NO: 26)
spv-S7
TCCAGAGGTACAGATCGGC
(SEQ ID NO: 27)
spv-S8
GAAGGAATACACTACTATAGG
(SEQ ID NO: 28)
spv-S9
GTGTCAGCAGTTGCATCATC
(SEQ ID NO: 29)
spv-S10
AGTGACCGATATGGAGAAGG
(SEQ ID NO: 30)
spv-S11
AAGCCTGTCTCTGCATTTCG
(SEQ ID NO: 31)
spv-S12
AACCGTTATGACATTAAGAGG
(SEQ ID NO: 32)
spv-S13
TAAGGCTCTCTATTAACTTAC
(SEQ ID NO: 33)
spv-S14
AACCGCTTCTGGCTGTAGC
(SEQ ID NO: 34)
spv-S15
CCGTAACAATGACATTATCCTC
(SEQ ID NO: 35)
[0069] The analysis result is given in SEQ ID NO: 3.
Example 3
Assay of Virulence Gene-Inactivated Salmonella Gallinarum SG2-d4 for Avirulence by Measurement of Invasion Efficiency into Avian Epithelial Cell
[0070] Salmonella Gallinarum and Salmonella pullorum , which are unique Salmonella species due to the lack of a motile flagella, are specifically infected to avian cells and can invade other animal cells but at very low efficiency. In this example, an in vitro cell invasion assay was conducted (Henderson S C et al, Infect Immun, (1999); 67(7):3580-3586) on the avian epithelial cell line BAT (Budgerigar Abdominal Tumor), provided from M D. Lee, Georgia University. The avirulent Salmonella Gallinarum variants SG3-d1d2 and SG3-d4, developed by the above-described gene deletion method, were expected to invade the host cell with very low efficiency by reduced level of TTSS-related protein. A recent research review on the infection mechanisms of pathogenic microorganisms has it that even when only a specific gene of SPI-1 is deleted, the Salmonella strain shows a decrease in invasion efficiency into epithelial cells (Lostroh C P et al. Microbes Infect, (2001); 3(14-15):1281-1291).
[0071] In the present invention, TTSS-related gene deletion was proven to lead to a decrease in virulence by measuring the efficiency of the invasion of the avian Salmonella variants into the avian epithelial cell line BAT.
[0072] Invasion efficiency into avian epithelial cells was measured on 24-well plates in triplicate, and mean values of three measurements were given. The BAT cell line was cultured at 37° C. in DMEM supplemented with 10% fetal bovine serum, 1 mM glutamine, 100 IU/ml penicillin and 100 μg/ml streptomycin under the condition of 5% CO 2 . The BAT cell line was seeded at a density of 2.5×10 5 cells/well into 24-well plates and incubated at 37° C. for 1˜2 days in a 5% CO 2 incubator to form monolayers of cells. After distribution of the cell and incubation for one day, the culture medium was changed out with antibiotic-free DMEM. For comparison of invasion efficiency, wild-type Salmonella Gallinarum SG3 (SGSC: 2293), the virulence gene-inactivated Salmonella Gallinarum variants SG3-d1, SG3-d2, SG3-d1d2 and SG3-d4, and SG9R, which is a commercially available live vaccine, were employed, with the non-pathogenic E. coli MG1655 serving as a control.
[0073] After being primarily seed cultured, all of test bacteria were vigorously incubated for 4˜5 hours in a main LB medium, and the cultures were diluted to OD 600 =1.0. To 200 μL of the animal cells incubated in the antibiotic-free medium, 200 μL of each of the culture dilutions was added so that the bacteria were aliquoted at a concentration of 2.0×10 8 cfu/ml per well. The plates were incubated at 37° C. for one hour in a 5% CO 2 atmosphere to allow the bacteria to penetrate into the epithelial cells. Thereafter, the medium was aspirated off and the plates were washed with 1×PBS to remove remaining microorganisms. Then, the epithelial cells were incubated at 37 ° C. for 2 hours in the presence of 50 μg/ml gentamycin in a 5% CO 2 incubator to clear the microorganisms remaining outside the cells. The antibiotic was removed by washing with 1×PBS. To examine the microorganisms which succeeded in penetrating into the epithelial cells, the animal cells were lyzed for 15˜30 min in 500 μl of 0.1% Triton X-100. The cell lysates were spread over LB plates and incubated overnight at 37° C. so that the microorganisms that had grown could be counted. To calculate the invasion efficiency, 200 μL of the microorganism culture with OD 600 =1.0 was also incubated.
[0000] Invasion Efficiency(%)=Count of Microorganisms invaded to Cell/Count of Microorganisms within Culture Medium ( OD 600 =1.0)×100
[0074] The BAT cell invasion efficiencies of the four transformed Salmonella Gallinarum variants prepared by the inactivation of virulence gene clusters were calculated.
[0075] Of them, the variant in which only the SPI-1 gene, cluster, responsible for cell invasion mechanism, was inactivated, was decreased in invasion efficiency by 84% compared to the wild-type. The SG3-d1d2 variant with the deletion of both SPI-1 and SPI-2 and the SG3-d4 variant with the deletion of all the four gene clusters were found to decrease in cell invasion efficiency by approximately 89% and 91%, respectively, compared to the wild-type Salmonella Gallinarum (SG3). The variants of the present invention were also remarkably reduced in invasion ability, in comparison to that of the commercially available live vaccine Nobilis SG9R. These data demonstrated that the inactivation of TTSS-related gene clusters decreases the virulence of Salmonella Gallinarum (see Table 4 and FIG. 2 ).
[0000]
TABLE 4
Index of
Internalization
Strain
Property
Genotype
(%)
Control
MG1655
Avirulent
Wild type
2%
Group
E. coli
SG3
Virulent
Wild type
100%
Salmonella
Gallinarum
(Wild-type,
SGSC No.
2293)
Nobilis
Salmonella
SG:: ΔrecA
67%
SG9R
Gallinarum
Live vaccine
(commercially
available)
Test Group
SG3-d1
Virulence
SG:: ΔSPI-1
16%
(avirulent
gene-deleted
Salmonella
Salmonella
Gallinarum )
Gallinarum
SG3-d2
Virulence
SG:: ΔSPI-2
34%
gene-deleted
Salmonella
Gallinarum
SG3-
Virulence
SG:: ΔSPI-1/
11%
d1d2
gene-deleted
ΔSPI-2
Salmonella
Gallinarum
SG3-d4
Virulence
SG:: ΔSPI-1/
9%
gene-deleted
ΔSPI-2/
Salmonella
Δspv/Δfae
Gallinarum
(SG3 100% = 0.36% invasion efficiency in practice)
[0076] The avirulence of Salmonella Gallinarum variant SG3-d4 was confirmed in vitro test which shows extremely low in invasion efficiency into avian epithelial cells, as was reconfirmed in animal tests and the results are given in Example 4.
Example 4
Assay of Salmonella Gallinarum SG3-d4 for Avirulence by Measuring Mortality of Chickens
[0077] The Research Institute of veterinary Science, Seoul National University, was entrusted with this assay. One-week-old brown egg layers (Hy-Line chicken) were employed in this assay, and they were divided into many groups of 10 which were separated in respective chicken houses before infection with pathogens. No vaccine programs were used on the experimental animals after they hatched.
[0078] Five avian Salmonella strains including the wild-type Salmonella Gallinarum SG3 (SGSC: 2293), the virulent gene cluster-inactivated Salmonella Gallinarum SG3-d2 and SG3-d4 (identified to decrease in virulence by in vitro invasion assay), the commercially available live vaccine Nobilis SG9R, and the non-pathogenic E, coli MG1655 were employed in the in vivo assay.
[0079] After being primarily seed cultured, the five strains were vigorously incubated for 4-5 hours to OD 600 =1.0 in a main LB medium, and the concentration of each of the cell cultures was adjusted to 1.0×10 8 cfu/ml. The bacteria was subcutaneously injected at an adjusted dose into the chickens which were the monitored for two weeks for mortality. Subsequently, the chickens which were alive were autopsied to examine lesions and to isolate bacteria.
[0080] For the two weeks after artificial, infection of the pathogens (1.0×10 8 cfu/mL), the chickens infected with Salmonella . Gallinarum (SG3) were observed and showed typical external syndromes such as low motility, blue diarrhea and low uptake of feedstuff, and looked to be dying. The mortality was not high, but an autopsy disclosed lesions in almost all the chickens.
[0081] In contrast, the chicken group infected with the Salmonella Gallinarum variant (SG3-d4) the avirulence of which was proven by in vitro invasion assay were observed to actively move and not die although some of them had diarrhea during the two weeks. Also, they were found to have almost no lesions in the autopsy. Therefore, the Salmonella Gallinarum variant of the present invention was again proven to have greatly decreased virulence. The chicken groups infected with the SG3-d2 variant in which the gene responsible for primary invasion into host cells remains intact while the SPI-2 gene involved in systemic infection and survival over phagocytosis is inactivated, or with the SG3-ds variant in which the spv gene known to participate in pathogenicity is inactivated, were observed to have low or no mortality (%). Thus, even the inactivation of single gene clusters had a great influence on the reduction of pathogenicity (see Table 5).
[0000]
TABLE 5
Frequency
of lesions
Geno-
Mortal-
in live
Strain
Property
type
ity (%)
birds (%)
Control
MG1655
Avirulent
Wild-type
0%
20%
(2/10)
Group
E. coli
SG3
Virulent
Wild-type
20%
88%
(7/8)
Salmonella
Gallinarum
(Wild-type,
SGSC No. 2293)
Nobilis
Salmonella
SG:: ΔrecA
0%
40%
(4/10)
SG9R
Gallinarum
Live vaccine
(commercially
available)
Test
SG3-d1
Virulence
SG:: ΔSPI-1
40%
17%
(1/6)
Group
gene-deleted
(avirulent
Salmonella
Salmonella
Gallinarum
Gallinarum )
SG3-d2
Virulence
SG:: ΔSPI-2
10%
0%
(0/9)
gene-deleted
Salmonella
Gallinarum
SG3-ds
Virulence
SG:: Δspv
0%
20%
(2/10)
gene-deleted
Salmonella
Gallinarum
SG3-d4
Virulence
SG::
0%
10%
(1/10)
gene-deleted
ΔSPI-1/ΔSPI-2/
Salmonella
Δspv/Δfae
Gallinarum
[0082] According to autopsy findings, the liver and spleen were swollen and weakened, with the significant frequency of greenish brown or bluish green liver lesions, in the chicken group infected with the wild-type Salmonella Gallinarum (SG3). Like the commercially available live vaccine Nobilis SG9R or the non-pathogenic E. coli MG1655, however, the virulent gene cluster-inactivated variants of the present invention (SG3-d1d2 and SG3-d4) were found to produce almost no lesions, and were demonstrated to be harmless to chickens.
Example 5
Comparison of the Productivity of ΦCJ1 Bacteriophage Specific to Salmonella Gallinarum Variants
[0083] Ultimately, the development of avirulent Salmonella stains is to apply to the production of Salmonella -specific lytic bacteriophages. The Salmonella variants prepared in Example 2 were proven to have greatly attenuated virulence in Examples 3 and 4. Finally, ΦCJ1 (Korean Patent Application No. 10-2008-121500/US20100135962), which specifically infects avian Salmonella , was used to examine a difference in bacteriophage productivity between the wild-type and the avirulent Salmonella Gallinarum variants.
[0084] The avian-specific bacteriophage ΦCJ1 was cultured on a mass scale, with the wild-type Salmonella Gallinarum strain (SG3) or the variant serving as a host cell. For this, each bacterial strain was cultured to an OD 600 of 0.5 (2.5×10 10 colony forming units (cfu)) in 50 ml of LB broth in a flask with agitation. ΦCJ1 was inoculated at 1.25×10 9 pfu (plaque forming unit) to form an MOI (multiplicity of infection) of 0.05, and allowed to stand for 20 min at 37° C., followed by additional incubation at 37° C. for 4 hours. Chloroform was added in an amount of 2% of the final volume and shakes for 20 min. After passage of the supernatant through a 0.2 μm filter, the titer of ΦCJ1 was counted.
[0085] ΦCJ1 was produced at a titer of 6×10 11 pfu/ml from the wild-type strain (SG3) and at a titer of 8×10 10 pfu/ml from the avirulent Salmonella Gallinarum variant (SG3-d4). These data demonstrated that the avirulent variants prepared by inactivating virulence gene clusters have no problems with infection with bacteriophages and can be used as host cells for producing bacteriophages (see Table 6). In addition, ΦCJ2 (US 20100158870) and ΦCJ3 (US 20100166709), which were both developed by the same applicant, were produced using the variant as a host cell. The host cell was found to allow the production of ΦCJ2 at a titer of approximately 2×10 10 pfu/ml and ΦCJ3 at a titer of approximately 5×10 9 pfu/ml. Like ΦCJ1, ΦCJ2 and ΦCJ3 were produced from the variant of the present invention, without significant difference from the wild-type.
[0000]
TABLE 6
Production
Titer of
ΦCJ1
Strain
Property
Genotype
(pfu/ml)
Control
SG3
Virulent
Wild type
6 × 10 11
Group
Salmonella
Gallinarum
(Wild-type,
SGSC No. 2293)
Test
SG3-d4
Virulence
SG3::
8 × 10 10
Group
Gene-Deleted
ΔSPI-1/ΔSPI-2/
(avirulent
Salmonella
Δspv/Δfae
Salmonella
Gallinarum
Gallinarum )
[0086] As described hitherto, the avirulent Salmonella Gallinarum variants, prepared by inactivating virulence genes, according to the present invention are useful as host cells for effectively producing Salmonella -specific lytic bacteriophages on an industrial scale with the advantage of cost saving. The avirulent Salmonella Gallinarum variants simplify the purification process taken to remove toxicity after bacteriophage production, thus greatly reducing the production cost and solving the safety problem of the products. In addition, the variants can be used as live vaccines that guarantee higher immunological effects and safety than do conventional vaccines.
[0087] Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. | The present invention relates to avirulent Salmonella Gallinarum variants by inactivating virulence gene clusters of Salmonella Gallinarum (SG), a main pathogen of avian salmonellosis, and various uses thereof notably in the production of Salmonella -specific lytic bacteriophages, pharmaceutical compositions and feed additives. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of and claims priority pursuant to 35 U.S.C. Section 120 from U.S. patent application Ser. No. 10/886,345 filed Jul. 7, 2004 now U.S. Pat. No. 6,879,052 which is a divisional of U.S. patent application Ser. No. 10/298,074 filed Nov. 15, 2002.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
In general, this invention relates to a system for providing electrical power. More specifically, this invention is directed to a system particularly adapted to provide reliable electrical power for the operation of a remote telecommunications facility.
Although it may be utilized in numerous applications, this invention is specifically adapted to provide power for the continuous operation of a remote telecommunications facility. With its core technology substantially composed of digital components, the telecommunications industry is heavily dependent on the continued supply of reliable electrical power. The critical nature of the functions performed by remote telecommunications facilities further emphasizes the need for a dependable power supply.
Most telecommunications facilities rely on a commercial power utility for electrical power and employ traditional devices, such as a transformer and switchgear, to safely receive and use the electrical power. To insure the facility's power supply is not interrupted, such as in the case of a black-out or other disturbance in the commercial power system, many telecommunications facilities have a system for providing backup power. Although various designs are used, many backup systems employ a diesel generator and an array of batteries. If power from the commercial utility is lost, the diesel generator takes over to supply power, and the battery array insures that power is maintained during the time it takes to switch from utility-supplied power to generator-supplied power. If the generator also fails, such as due to a mechanical malfunction or to the depletion of its fuel source, then the battery array is able to provide power for an additional period of time.
There are several disadvantages inherent in the current manner in which power is supplied to telecommunications facilities. First, the cost of local electrical utility service has risen dramatically in recent years and, by all accounts, will continue to rise. Thus, the cost of local electrical utility power is a large component of the facility's overall power expenses. Next, as the facility's power demands have increased, the number of batteries required to provide an adequate amount of power for a reasonable period of time has also increased. Clearly, the component cost of the system increases with the greater number of batteries required. In addition, the greater number of batteries required has significantly increased the space required to house the backup system, which has increased the spacial cost of the systems. Finally, it is known that generators suffer from certain reliability problems, such as failing to start when needed because of disuse or failed maintenance. Therefore, the reliability of the backup systems could be improved.
The power system of the present invention overcomes these disadvantages by providing reliable electrical power that is not initially dependent on a commercial electrical utility and that does not employ an array of batteries. The system, therefore, is more cost efficient and requires less space than the present manner of providing power to facilities. The invention employs redundant sources of power, and thus, is uninterruptible. Also, the system employs power generating components that have less of an impact on the environment than the current manner in which power is supplied. Moreover, the system may be constructed at a manufacturing site and then moved to the facility. Thus, the system of the present invention provides power to a telecommunications facility in a manner that is less expensive, that requires less space, that is movable, and that is environmentally friendly.
BRIEF SUMMARY OF THE INVENTION
The present invention includes a power system that is designed to provide reliable electrical power to a facility, and specifically to a telecommunications facility. The system includes a number of microturbine generators adapted to provide AC power. The system is configured so that the microturbine generators are fueled initially by natural gas supplied by a commercial utility. In the event the natural gas supply fails, the system includes a propane storage tank to provide fuel to the microturbine generators. The system also has an array of rectifiers to convert the AC power from the microturbine generator to DC power. If both of the microturbine generators' fuel sources fail or become exhausted, power is supplied to the rectifiers by a commercial electrical utility, and the system includes components to receive the utility-supplied electricity. The system also includes a number of hydrogen-powered proton exchange membranes that are operable to supply DC power directly to the facility if both the microturbine generators and the electrical utility fail. Finally, the system includes a number of super capacitors that are operable to maintain power during the time required to change between power sources.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The present invention is described in detail below with reference to the attached figure, wherein:
FIG. 1 is a schematic diagram of the present invention without the sensing/control mechanism.
FIG. 2 is a functional block diagram of the major components of the present invention; and
FIG. 3 is a block diagram showing the physical relationship of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention includes both a system and a method for providing reliable electrical power to a facility, and specifically to a telecommunications facility. The system provides redundant sources of electrical power including a number of microturbine generators and a number of proton exchange membranes (PEMs). The system also includes a number of capacitors to provide power during the time it takes to switch between power sources. By employing these components, the system avoids the need for an array of batteries and is more cost efficient than the current method for providing power to telecommunications facilities.
The present invention is best understood in connection with the schematic diagram of FIGS. 1–3 . In FIG. 1 , the power system of the present invention initially comprises a number of microturbine generators 10 . A turbine includes a rotary engine actuated by the reaction or impulse or both of a current of fluid, such as air or steam, subject to pressure and an electrical generator that utilizes the rotation of the engine to produce electrical power. Microturbine generators are a recently developed technology and have not been employed to provide power to a telecommunications facility. A microturbine is smaller and more compact than more common turbines and creates a lower amount of harmful emissions than both more common turbines and diesel generators. A microturbine generator includes a system for receiving fuel, a microturbine for converting the fuel received to electrical power and a digital power controller. Thus, a microturbine generator is able to utilize a fuel source such as natural gas or propane to produce electrical power. One microturbine generator that is suitable for the present invention is the Capstone 60 MicroTurbine™ system produced by the Capstone Turbine Corporation of Chatsworth, Calif. As is understood by those in the art, the number of microturbine generators used in the inventive system depends on the amount of power required by the destination facility.
The present invention is designed to provide fuel from two different sources to microturbine generators 10 . Initially, microturbine generators 10 are fueled by natural gas. The natural gas is received in primary fuel valve 20 which is coupled to primary fuel pipe or line 30 . Pipe 30 is also coupled to a series of valves 40 , and each of valves 40 is also coupled to an input of a corresponding mixing box 50 . The output of mixing boxes 50 is coupled to the input of one of microturbine generators 10 . Microturbine generators 10 may also be powered by propane stored in a local storage tank 60 . The propane is received through backup fuel valve 70 which is coupled to backup fuel pipe or line 80 . Pipe 80 is also coupled to a series of valves 90 , and each of valves 90 is coupled to an input of mixing boxes 50 . Mixing boxes 50 is operable to combine fuel received with any necessary additional components and thereafter provide appropriate amounts of fuel to microturbine generators 10 . Mixing boxes 50 are capable of receiving and responding to a control signal by at least opening or closing lines. In addition, valves 20 , 40 , 70 and 90 are also capable of receiving and responding to a control signal by at least opening and closing.
Microturbine generators 10 utilize the natural gas or propane fuel to produce AC electrical power. The output electrical current from each microturbine generator 10 is coupled to one end of a circuit breaker 100 in order to protect the circuit such as, for example, if microturbine generator 10 causes a power surge. The opposite end of circuit breakers 100 is coupled to a bus line 110 that is also coupled to switch 120 . Bus line 130 is coupled to the output of switch 120 and to a number of rectifiers 140 . As is known, a rectifier is capable of receiving an AC input and rectifying or converting that input to produce a DC output. Thus, rectifiers 140 convert the microturbine-produced AC power to DC power. The output of rectifiers 140 is coupled to bus line 150 which is connected to the power distribution unit 160 in the destination facility. Power distribution unit 160 contains connections into the telecommunications facility's power lines, and/or provides connections to the various telecommunications equipment. Power distribution unit 160 may also contain additional circuit breakers or other power switch gear or safety devices and/or circuits, including circuits to limit the voltage or current provided to the facility's power lines, and monitoring/measuring equipment. A number of super capacitors 170 are also connected to bus line 150 .
The system of the present invention is also capable of receiving power from a commercial utility. Utility-supplied power is received on bus line 180 , and a connection to ground is provided through line 190 . Bus line 180 is connected to one side of switch 200 , and the other side of switch 200 is coupled to the primary side of transformer 210 . As is known, a transformer is capable of receiving an input signal on its primary side and producing a corresponding signal on its secondary side that is electronically isolated from the input signal. The secondary side of transformer 210 is coupled to one side of a main circuit breaker 220 . The opposite side of main circuit breaker 220 is coupled to one side of a number of circuit breakers 230 . The opposite side of one of the circuit breakers 230 is connected to bus line 240 ; the remaining circuit breakers 230 are available to provide electrical power for additional applications or systems. Bus line 240 is also connected to an input of switch 120 .
The power system of the present invention also includes a number of proton exchange membrane fuel cell modules (PEMs) 250 . A PEM is a device that is capable of converting dry gaseous hydrogen fuel and oxygen in a non-combustive electrochemical reaction to generate DC electrical power. Because the only by-products of this reaction are heat and water, a PEM is friendly to the environment and may be used indoors and in other locations where it is not possible to use a conventional internal combustion engine. In addition, unlike a battery, a PEM is capable of providing electrical power for as long as fuel is supplied to the unit. One PEM that is suitable for the present invention is the Nexa™ power module manufactured by Ballard Power Systems Inc. of Burnaby, British Columbia, Canada. As with microturbine generators 10 , the number of PEMs 250 required is dependent on the amount of power required by the destination facility.
Hydrogen fuel is supplied to the PEMs 250 from a number of storage tanks 260 located in a vault 270 . Each of the storage tanks 260 is coupled to a valve 280 . Each of valves 280 is coupled to a valve 290 which is also coupled to a pipe 300 . Thereafter, pipe 300 is coupled to a series of valves 310 , and each of valves 310 is coupled to one of the PEMs 250 . The output of the PEMs 250 is connected between bus line 150 and a circuit breaker 320 . As stated above, super capacitors 170 and the power distribution unit 160 of the facility are also connected to bus line 150 . The other side of circuit breakers 320 is connected to a bus line 330 . There are two switches connected to bus line 330 . Switch 340 is coupled to bus line 330 on one side and bus line 150 on the other side. Switch 350 is coupled to bus line 330 on one side and bus line 360 on the other side. Unlike bus line 150 , bus line 360 is only connected to power distribution unit 160 of the facility.
The power system of the present invention also comprises a number of sensing and control mechanisms (not expressly shown) for determining which fuel source to activate and which power source to engage. As is known, the sensing mechanisms may be separate devices or may be integral to the valves, bus lines, and/or devices being monitored. Likewise, the control mechanism may be a separate device, such as a programmable logic controller, or may be part of one of the components already described, such as the microturbine generators 10 . It is also possible that the sensing and control mechanisms may be combined into a solitary mechanism that may be a stand-alone unit or may be combined with one of the components already described.
The operation of the power system may be understood by referring to FIG. 2 . It should be noted that the present invention is represented in FIG. 2 by functional blocks. Thus, sensing/control mechanism 370 is shown as one unit when in fact the sensing and control devices actually may be several devices as discussed previously. Of course, all of the sensing and control devices actually may be placed together in a separate unit, such as a programmable logic controller, as shown in FIG. 2 .
In operation, the sensing/control mechanism 370 initially causes valves 380 (which include valves 40 and 90 shown in FIG. 1 ) to allow natural gas to flow from the utility source to the microturbine generators 390 and to prevent the flow of propane to microturbine generators 390 . Sensing/control mechanism 370 also initiates operation of the microturbine generators 390 . In addition, sensing/control mechanism 370 also causes valves 400 (which include valves 310 shown in FIG. 1 ) to prevent the flow of hydrogen to the PEMs 410 and causes the PEMs 410 to remain off. In this manner, microturbine generators 390 produce AC power using utility-supplied natural gas. The AC current produced by the microturbine generators passes through switch 420 to rectifiers 430 where it is converted to DC current. Thereafter, the DC current from rectifiers 430 is provided to the telecommunications facility and to super capacitors 440 . As is well known, when they first receive DC current, super capacitors 440 charge to the level of the DC power provided.
If sensing/control mechanism 370 determines that there is an interruption in the utility-supplied natural gas, then it will cause valves 380 to prevent the flow of natural gas and allow the flow of hydrogen to microturbine generators 390 . Switch 420 remains in the same position as before and valves 400 continue to prevent the flow of hydrogen to PEMs 410 . In this configuration, microturbine generators 390 continue to generate AC power but now their fuel is propane.
If the sensing/control mechanism 370 determines that both fuel sources for microturbine generators 390 have failed or that there is some other disturbance in the microturbine-supplied power which causes that power to become inadequate, then sensing/control mechanism 370 will cause valves 380 to close and deactivate the microturbine generators 390 . Sensing/control mechanism 370 will set switch 420 so that rectifiers 430 receive AC power from the electric utility. In addition, sensing/control mechanism 370 will keep valves 400 closed and PEMs 410 deactivated.
If sensing/control mechanism 370 determines that the electric utility has failed or the power it supplies has become inadequate and the microturbine generators 390 remain deactivated, such as due to a lack of fuel or a malfunction, then sensing/control mechanism 370 will cause valves 400 to open which allows hydrogen to flow to PEMs 410 . Thereafter, the control mechanism will activate PEMs 410 . In this manner the PEMs 410 provides DC power to the telecommunications facility and to super capacitors 440 .
In each of the above scenarios, super capacitors 440 provide electrical power during the time it takes for the control mechanism to switch from one power source to another. Thus, super capacitor 440 must have a discharge time greater than the longest time required to switch between power sources. One super capacitor that is suitable for this invention is manufactured by Maxwell Technologies located in San Diego, Calif.
Referring now to FIG. 3 , significant portions of the present invention may be enclosed in a modular, weatherproof container, indicated by the numeral 450 , that is transportable by truck or rail. For example, all of the components shown in FIG. 1 , except tank 60 and vault 270 with the components contained therein, may be pre-assembled and pre-wired with the sensing/control mechanism(s) and then placed in container 450 before being shipped to a facility. Once at the facility, propane storage tank 460 and hydrogen storage vault 470 are provided and coupled to container 450 . Once utility-supplied natural gas and electricity lines have been coupled to container 450 and the output of container 450 is coupled to the telecommunications facility 480 , then the unit may be activated.
As discussed, the power system described above initially employs microturbine generators to provide electrical power for a telecommunications facility. The microturbine generators are compact, efficient (both in terms of space and fuel) and reliable. By relying on microturbine generators as the main source of power, the system avoids both the reliability problems and environmental hazards inherent in internal combustion generators and the costs and environmental concerns associated with commercial electrical power. The power system also provides redundant sources of power, specifically from a commercial electrical utility and a number of proton exchange membranes, and therefore is uninterruptible. Finally, the system provides a number of super capacitors to provide electrical power during the time it takes to switch between power sources. By employing super capacitors and proton exchange membranes, the power system avoids the use of batteries thereby saving significant cost and space.
It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, all matter shown in the accompanying drawings or described hereinabove is to be interpreted as illustrative and not limiting. Accordingly, the scope of the present invention is defined by the appended claims rather than the foregoing description. | Disclosed is a method of supplying DC power to equipment using proton exchange membranes (PEMs). PEMs run on hydrogen to produce DC electrical power. In the disclosed embodiment these PEMs are used as an alternative source of power to AC sources. One of these other sources is generated by an array of gas turbines. Another source is provided by a commercial utility. AC from these sources is converted using rectifiers. Capacitors are used to bridge when switching between energy sources. | 8 |
TECHNICAL FIELD
The present disclosure relates to heating and cooling equipment, and more specifically to a valve package for heating and cooling equipment that prevents attached supply and return lines from being damaged during shipping.
BACKGROUND OF THE INVENTION
Heating and cooling equipment is typically assembled in the field from basic components such as ductwork and conduits, because assemblies can be easily damaged during shipping. As such, the cost savings that might be realized from pre-assembling such equipment is offset by the additional cost that is needed to repair assemblies that are damaged during shipment.
SUMMARY OF THE INVENTION
A heating, ventilating and air conditioning (HVAC) fan powered or non-fan powered assembly that includes a duct and a coil assembly coupled to the duct is provided. A supply line and return line are connected to the coil assembly, such as to provide heated or chilled water. The HVAC assembly could have either one set or two sets of supply and return lines. A first hanger assembly that includes a hinged frame, a hinge, a screw, a threaded hole, and a support hole encircles the supply line, and a second hanger assembly that includes a hinged frame, a hinge, a screw, a threaded hole, and a support hole encircles the return line. A support bracket is connected to the duct and has a first raised channel with a hole and second raised channel with a hole. A first threaded connector is connected to the threaded hole of the first hanger assembly and the first hole in the raised channel of the support bracket and threaded into a square nut located under support bracket channel between the support bracket and duct. A second threaded connector is connected to the threaded hole of the second hanger assembly and the second hole in the raised channel of the support bracket and threaded into a square nut located under support bracket channel between the support bracket and duct.
Other systems, methods, features, and advantages of the present disclosure will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present disclosure, and be protected by the accompanying claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
Aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views, and in which:
FIG. 1 is a diagram of a heating, ventilating and air conditioning (HVAC) assembly with a valve package in accordance with an exemplary embodiment of the present disclosure;
FIG. 2 is a diagram of a support in accordance with an exemplary embodiment of the present disclosure; and
FIG. 3 is a side view showing a support in accordance with an exemplary embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
In the description that follows, like parts are marked throughout the specification and drawings with the same reference numerals. The drawing figures might not be to scale and certain components can be shown in generalized or schematic form and identified by commercial designations in the interest of clarity and conciseness.
FIG. 1 is a diagram of a heating, ventilating and air conditioning non-fan powered (HVAC) assembly 100 with a valve package in accordance with an exemplary embodiment of the present disclosure. HVAC assembly 100 includes an inlet assembly 102 , which is installed in duct 112 . Duct 112 is coupled to coil housing 110 , which can contain a suitable arrangement of tubing coils to allow a heat exchange medium to be supplied to air flowing through duct 112 , as supplied by inlet assembly 102 .
HVAC assembly 100 includes manual and automated valve assemblies that are fed by supply line 104 and return line 106 , which can be suitable metal or non-metallic conduits that carry a suitable heat exchange medium, such as water. Supply line end 114 and return line end 116 are expanded and sealed, which simplifies forming a connection to the heated or chilled water supply and return pipes by eliminating the need for a coupling and by reducing the number of joints that require brazing. In addition, supply line end 114 and return line end 116 allows HVAC assembly to be shipped with a positive or negative pressure inside of the sealed pipes, and Schrader valve 118 can be used to determine whether the positive or negative pressure has been maintained during shipping, so as to be able to detect whether any leaks or other damage might be present.
The heat exchange medium is provided to coil housing 110 by supply line 104 , circulates through the coils contained within coil housing 110 where it heats or cools air from duct 112 and inlet assembly 102 , and returns through return line 106 , where it can be heated or cooled, respectively. In this manner, a heated heat exchange medium can be used to heat air from duct 112 (in which case the heat exchange medium is cooled) and a chilled heat exchange medium can be used to cool air from duct 112 (in which case the heat exchange medium is heated). In addition, although a single set of supply lines is shown, two sets of supply lines can be used, such as where one set is used for heating and a second set is used for cooling. In this exemplary embodiment, two sets of coils can also be provided, or suitable valve connections can be used to switch between the heating supply lines and the cooling supply lines, but in any configuration, support 108 can be used to prevent the supply lines from being damaged during shipment.
In order to allow supply line 104 , return line 106 and the associated valves and actuators to be pre-installed onto coil housing 110 and the associated coils, it is necessary to provide support to supply line 104 and return line 106 in a manner that facilitates shipping while preventing shipping-related damage. Prior solutions have utilized a handle structure that also functions as a support for the associated duct, but such handle structures can contribute to shipping-related damage by facilitating use of supply line 104 and return line in a manner for which they were not designed. In order to prevent such use, the present disclosure provides support 108 , which can be contained within shrink wrap or other materials that can also cover supply line 104 , return line 106 and the associated valves and actuators. In this manner, personnel are not provided with a handle or other means for grasping supply line 104 or return line 106 during shipping or installation, and damage to supply line 104 , return line 106 , the associated valves or actuators or coils contained within coil housing 110 can be prevented. Support 108 utilizes duct 112 for support, and does not support duct 112 , which allows support 108 to be smaller and less expensive than prior solutions that utilize a handle structure that also functions as a support for the associated duct.
FIG. 2 is a diagram of support 108 in accordance with an exemplary embodiment of the present disclosure. Support 108 includes hangers 202 and 210 , which can be fabricated from copper or other suitable materials. Hanger 210 encloses supply line 104 and hanger 202 encloses return line 106 , so as to provide a firm support for supply line 104 and return line 106 without providing an area that can be readily grasped, so as to prevent misuse or mishandling of support 108 during shipping or installation.
Support 108 includes lateral supports 204 and 208 , which are coupled to hangers 202 and 210 , respectively. In one exemplary embodiment, lateral supports 204 and 208 can be all-thread connectors, which can be screwed into a threaded hole in each of hangers 202 and 210 , respectively, or which can be brazed, welded, riveted or otherwise suitably attached. Lateral supports 204 and 208 are also coupled to support bracket 206 , such as by being inserted into holes in a raised channel of support bracket 206 and screwed into squared threaded nuts 220 and 222 , respectively, located in the raised channel of support bracket 206 located between support bracket 206 and duct 112 , or by being brazed, welded, riveted or otherwise suitably attached to support bracket 206 . In one exemplary embodiment, the use of all thread connectors with coordinated threads on hangers 202 and 210 and support bracket 206 can allow the tension between supply line 104 , return line 106 and support bracket 206 to be adjusted, so as to provide a firm support for supply line 104 and return line 106 without providing too much lateral force, which can cause supply line 104 , return line 106 or the connection of supply line 104 and return line 106 to coil housing 110 or the coils contained within coil housing 110 to be damaged.
Support bracket 206 includes installation holes 212 , which allow support bracket 206 to be bolted, riveted or otherwise attached to duct 112 at a suitable location. Likewise, support bracket 206 can be brazed, welded or otherwise suitably connected to duct 112 or other suitable structures.
FIG. 3 is a side view showing support 108 in accordance with an exemplary embodiment of the present disclosure. In this exemplary embodiment, hangers 202 and 210 can each include a hinged frame 214 , having a hinge 216 and associated screw 218 . Hangers 202 and 210 can be attached to supply line 104 return line 106 at a suitable location by closing hinged frame 214 around supply line 104 or return line 106 , and then by installing screw 218 into hinged frame 214 or otherwise connecting the mating ends of hinged frame 214 opposite hinge 216 , such as welding, brazing or with a bolt. In this manner, lateral supports 204 and 208 can be installed in hangers 202 and 210 and support 206 before hangers 202 and 210 are secured to supply line 104 and return line 106 , where suitable.
In operation, support 108 allows supply line 104 and return line 106 to be installed on duct 112 and coil housing 110 in a manner that allows supply line 104 and return line 106 to be encased in packaging or otherwise protected from being used to move the assembly that includes duct 112 and coil housing 110 , so as to protect supply line 104 and return line 106 from being damaged or from causing damage to duct 112 and coil housing 110 during shipment and installation. Support 108 thus allows complex HVAC assemblies to be manufactured in a single location and shipped to diverse installations without creating an incentive for workers to improperly handle the assembly in a manner that can damage the components of the assembly, which can require subsequent and expensive rework or replacement.
It should be emphasized that the above-described embodiments are merely examples of possible implementations. Many variations and modifications may be made to the above-described embodiments without departing from the principles of the present disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims. | A heating, ventilating and air conditioning (HVAC) assembly that includes a duct and a coil assembly coupled to the duct. A supply line and return line are connected to the coil assembly. A first hanger assembly encircles the supply line, and a second hanger assembly encircles the return line. A support bracket has a first raised channel with a hole and second raised channel with a hole. A first threaded connector is secured using a square nut located in under the raised channel of the bracket, and a second threaded connector is connected to the threaded hole of the second hanger assembly and the second hole in a raised channel of a bracket and secured using a square nut located in under the raised channel of the bracket. | 5 |
FIELD OF THE INVENTION
The present invention relates to a device for intermittent application of particles of a powdered developer to the recording surface of a magnetographic printer.
BACKGROUND OF THE INVENTION
Magnetographic printing machines are known which in response to the reception of electrical signals from a control unit make it possible to form images, for instance images of characters, on a printing substrate, typically a sheet or strip of paper. In these printers, which are similar to those described and shown in U.S. Pat. Nos. 3,161,544 and 4,072,957, printing of the images is attained by first forming a latent magnetic image, based on the signals received, on the surface of a magnetic recording element. The recording element is coated with a film of magnetic material and is generally in the form of a rotating drum or an endless belt. The latent magnetic image is then developed, or in other words made visible, with the aid of a powdered developer comprising particles of thermoplastic resin enclosing magnetic particles and pigments, which is attracted only by the regions of the recording element on which the latent image has been recorded. The developer then forms an image in powder on the surface of the element, and this powder image is then transferred to the printing substrate.
In order to permit the formation of the latent magnetic image on the surface of the recording substrate, these machines are provided with a recording device known as a transducer, which includes one or more magnetic recording heads into proximity with which the recording element is displaced. Each of these heads generates a magnetic field, whenever it is excited for a brief moment by an electric current of suitable intensity, creating magnetized domains of small dimensions on the surface of the recording element. These domains are virtually punctiform and are generally known as magnetized points.
A set of these magnetized points comprises the latent magnetic image. The portion of the surface of the recording element that passes before each head is conventionally known as the data recording track. The recording element generally includes a plurality of tracks, which may be subjected to recording either individually, in the course of successive recording operations, or simultaneously in the course of a single operation.
Magnetographic printing machines have already been made in which the transducer includes as many magnetic heads as there are tracks on the recording element. The heads are disposed side by side and are aligned along a direction transverse to the direction of displacement of the recording element. Since in these machines each track is associated with each of the transducer heads, respectively, recording of a latent image on the recording element is accomplished in the course of a single displacement revolution of this element along its endless orbit. Accordingly, these machines are capable of functioning at a high printing speed, which may for example be as high as a hundred pages per minute. Nevertheless, for certain applications, such high speed is not always necessary, so that a less-powerful magnetographic printer, that is also less expensive, equipped with a transducer that includes a number of magnetic heads notably less than the number of tracks of the recording element, may be sufficient. Such a magnetographic printing machine is known from U.S. Pat. No. 4,072,957, where the transducer includes only a single magnetic head, which is mounted in such a way that it can be displaced along a magnetic recording drum in the direction parallel to the axis of rotation of the drum.
In this known machine, recording of a latent magnetic image is performed track by track. Recording of the data in a track located facing the head is performed in the course of one complete revolution of the drum. At the end of this revolution, the head has been displaced so that it is facing the following track and allows recording of this following track in its turn. Under these conditions, the recording of the latent image on the drum is performed in as many revolutions of the drum as there are tracks on the drum. The development of the latent image, that is, the depositing of particles of developer onto the drum, is not undertaken until the formation of the image on the drum is completed. This operation is performed by means of an applicator device of a known type, which in the machine described in the aforementioned U.S. Pat. No. 4,072,957 includes a magnetic cylinder mounted on a shaft parallel to the axis of rotation of the drum. This cylinder, placed in proximity with the surface of the drum, is disposed in such a way as to be in contact with the developer particles contained in a reservoir placed beneath the drum. Thus when the magnetic cylinder revolves, the developer particles, which are driven to rotate by this cylinder, are moved to the vicinity of the surface of the drum and upon being attracted by the magnetized points on the surface are deposited on the portions of the surface on which the latent image has been formed. The particles thus deposited then travel past a transfer roller, which is normally pressed against the surface of the drum, and are thus transferred to a sheet of paper that at that moment is engaged between the drum and the transfer roller.
In this applicator device, the magnetic cylinder is not driven to rotate continuously but rather only for one revolution of the drum, following the formation of a latent image on the drum. Thus, during the periods of formation of latent images when no sheet of paper is engaged between the drum and the transfer roller, developer particles are prevented from being deposited on the drum and so do not soil the transfer roller. This applicator device, which functions intermittently and makes it possible to apply developer particles to the drum without causing clouds of particles capable of causing pollution inside the machine; however, it is still not completely satisfactory, because the drum is located a very slight distance away from the magnetic cylinder, and when the particles travel past the cylinder, the magnetized points that have been formed on the drum are necessarily exposed to the action of the magnetic flux generated by the cylinder, with the risk that they will be greatly altered or even erased.
Certainly, this disadvantage could be overcome by using an applicator device described in French Patent No. 2.408.462, which includes both a reservoir disposed below the recording element and containing developer particles and also a transport element arranged to place these particles in the vicinity of the surface of the recording element. The applicator device also includes a fixed deflector, interposed between the surface and the transport element to gather the particles transported by the transport element and arranged so that with this surface it forms a substantially prismatic spout, in which the gathered particles accumulate. The accumulated particles finally come into contact with the surface and are entrained by it in the direction of the apex of the prism comprising the spout, and the particles driven beyond this apex remain applied only to the magnetized points formed on the surface.
This applicator device, which causes no alteration whatever of the magnetized points and generates no pollution whatever inside the machine, nevertheless has the disadvantage of not assuring good development of the latent images when the transport element with which it is provided is driven intermittently rather than continuously.
OBJECT AND SUMMARY OF THE INVENTION
The present invention overcomes these disadvantages and proposes a device, mounted in a magnetographic printer in which the recording of each latent image is accomplished in the course of a plurality of successive displacement revolutions of the recording element along its endless orbit, which makes it possible to apply developer particles intermittently to the surface of the recording element, without causing pollution or disturbing the latent images that have been formed on the recording element.
More precisely, the present invention relates to a device for intermittent application of particles of a powdered developer to the recording surface of a magnetographic printer, in which the surface is driven by displacement along a predetermined closed orbit that makes it possible for it to move via a transfer station, where the developer that has been deposited on the surface is transferred to a printing substrate. The applicator device includes a device designed to apply developer particles permanently to the recording surface, and is characterized in that the recording surface cooperates with a device for recording latent images, arranged to form a latent image on this surface in the course of a plurality of successive displacement revolutions of the surface. The applicator device further includes a particle eliminator device disposed along the orbit, downstream of the point of application of the particles to the surface by the applicator device, between this application point and the transfer station; the eliminator device is arranged to pull away the particles of developer located on the surface, except during the last of the successive displacement revolutions of the surface.
The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of exemplary embodiments, taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a magnetographic printing machine equipped with a particle applicator device according to the invention;
FIG. 2 is a view showing the structure of the recording device, and the control devices for actuating the particle applicator device with which the machine shown in FIG. 1 is equipped;
FIG. 3 is a sectional view showing in detail the embodiment of part of the applicator device of the machine shown in FIG. 1;
FIG. 3A is a view on a large scale intended to show the profile of the actuation shaft of the squeegee that is part of the applicator device shown in FIG. 3; and
FIG. 4 is a diagram of the control circuit used for controlling the positioning of the squeegee belonging to the applicator device in FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The printing machine schematic shown in FIG. 1 is a machine that prints sheets of paper that are drawn in succession and continuously from a supply magazine 10.
This machine includes a recording element, which in the example described comprises a drum 11 provided with a magnetic recording surface 12. The drum 11, which is mounted such that it can rotate about a horizontal axis 13, is driven to rotate in the direction indicated by the arrow F by an electric motor (not shown). The recording of information on the drum is accomplished by a recording device 14, the structure of which will be described hereinafter. It is assumed that this device includes a plurality of magnetic heads. Each of these heads, each time it is excited for a brief moment by an electric current, generates a variable magnetic field, the effect of which is to create virtually punctiform magnetized zones 15 on the cylindrical surface 12 of the drum that moves past the heads. A set of these zones comprises a latent magnetic image corresponding to an image to be printed. The magnetized zones then travel past an applicator device 16 disposed beneath the drum 11, which makes it possible to apply particles of a powdered developer, contained in a reservoir 17, to the cylindrical surface of the drum. The structure of this applicator device will also be described in detail hereinafter. In principle, the particles of developer that are thus applied to the drum by the device do not adhere anywhere except to the magnetized zones of the drum, and so they form an image in powder on the surface 12 of the drum. A retouching device 18 past which the image travels makes it possible to remove any developer particles that have adhere anywhere besides to the magnetized zones of the drum, as well as particles that are present in excessive quantity on these zones. It should be noted here that the developer thus deposited on the surface 12 of the drum comprises fine particles of thermoplastic resin containing magnetic particles and pigments; this resin is capable of melting when it is exposed to a heat source, which causes it to be affixed to a sheet of paper to which the developer has been transferred. After that, the developer particles that remain on the drum 11 after moving past the retouching device 18 are normally transferred in virtual totality to a sheet of paper 19, which after it has been removed from the magazine 10 is pressed by a transfer roller 20 against the surface of the drum 11. The region H where the roller 20 comes into contact with the surface of the drum whenever a sheet is not engaged between the roller nd the drum comprises the transfer station. It is at this station that the transfer of the powdered image that has been formed on the surface of the drum 11 to a sheet of paper engaged between the drum 11 and the roller 20 takes place. The developer particles that still remain on the surface of the drum once the transfer has been completed are then lifted by a cleaning device 21. The magnetized zones that have travelled past the cleaning device 21 then travel past an erasing device 22, which makes it possible for the portions of the drum 11 that have thus been demagnetized by this last device to be capable of re-magnetization when they once again travel past the recording device 14.
The structure of the recording device with which the machine shown in FIG. 1 is equipped is shown in FIG. 2. Turning now to FIG. 2, it can be seen that the shaft 13 about which the drum 11 rotates is supported at its ends by two vertical support plates 30 and 31 that are integrally joined to one another by means of a transverse connecting plate 32. The plates 30 and 31 also support a guide bar 33 disposed parallel to the shaft 13 of the drum 11. A carriage 34, mounted to slide on the bar 33, may be displaced in increments along a direction parallel to the shaft 13 of the drum by means of a threaded rod 35 that is integral with the drive shaft of an electric motor 36, which in turn is fixed to the vertical plate 30. Magnetic heads T1, T2, T3, . . . , Tn are disposed at regular intervals on the carriage 34, being placed in such a manner that they are located in the immediate proximity of the surface 12 of the drum -1.
When the motor 36 is excited, the magnetic heads, driven by the carriage 34, are simultaneously displaced in a direction parallel to the shaft 13 of the drum 11. The set comprising the carriage 34 and the magnetic heads T1, T2, T3, . . . , Tn can thus be displaced between two limit positions, one of which, LG, is shown in solid lines in FIG. 2 and the other, LD, is shown in dot-dash lines, also in FIG. 2. The portion of the surface of the drum 11 that travels past each of these heads when the carriage 34 is immobilized is conventionally known as a track. In FIG. 2, these tracks, which are circular, have been shown as dashed lines and identified by reference symbols such as P11, P12, . . . , P16, P21, . . . , P26, P31, . . . , Pn1, . . . , Pn6. For the sake of clarity in the drawing, the tracks have been shown in FIG. 2 in positions spaced relatively far apart from one another. However, it should be noted that in reality these tracks are quite close to one another; in the example described, the distance separating two adjoining tracks is on the order of 100 m. For recording information on the drum 11, these tracks are used in groups of 6 tracks, and each of the groups is associated respectively with each of the magnetic heads of the recording device 14. Thus the six tracks P11-P16 are intended to receive the information recorded by means of the head T1. Similarly, the six tracks P21-P26 are intended to receive the information recorded by means of the head T2, and so forth for the following groups of tracks. The heads T1, T2, T3, . . . , Tn are positioned on the carriage 34 in such a manner that when the carriage is immobilized in its limit position LG (on the left in FIG. 2), each of these heads is located facing the first track of the group with which it is associated. Thus in this position, the head T1 is located facing the track P11, the head T2 is located facing the track P21, and so forth, and the final head Tn faces the track Pn1. In the course of the same revolution of the drum 11, it is thus possible to record information simultaneously on tracks P11, P21, P31, . . . , Pn1. A clock disk D, affixed to the shaft 13 of the drum 11, is provided with an aperature, which upon each revolution of the drum allows a beam of light emitted by a light source L and sent toward a photoelectric cell PH to pass through for a brief instant. Each time this aperature allows the beam of light to pass through, or in other words each time the drum 11 has completed one revolution, the cell PH delivers an electrical signal to an electrical control circuit of a known type (not shown), which is arranged accordingly to control the instantaneous excitation of the motor 36, and consequently the very rapid displacement of the carriage 34 by one increment. The signal sent by this cell PH when the recording of the tracks P11, P21, P31, . . . , Pn1 is completed has the effect of moving the heads T1, T2, T3, . . . , Tn to face the tracks P12, P22, P32, . . . , Pn2, respectively. Thus in the course of a second revolution of the drum 11, information can be simultaneously recorded on tracks P12, P22, P32, . . . , Pn2. The electrical signal sent by the cell PH at the end of this second revolution causes the displacement of the carriage 34 once again by one increment, which moves the heads T1, T2, T3, . . . , Tn to face the tracks P13, P23, P33, . . . , Pn3; these tracks are those that in FIG. 2 are located immediately to the right of the tracks P12, P22, P32, . . . , Pn2. In the course of a third revolution of the drum, information can then be simultaneously recorded on tracks P13, P23, P33, . . . , Pn3.
The recording of information on the following tracks is accomplished in the same manner as described above; the carriage 34 is displaced by on increment in the direction of its limit position LD at the end of each of the rotations of the drum 11. It will accordingly be understood that with the recording device shown in FIG. 2, six complete cyles of rotation of the drum are required for recording a latent magnetic image on the drum. Naturally, in the course of the first five of these six revolutions, the erasing device 22 is invalidated, so that portions of the latent image that have already been recorded on the drum will not be erased. The erasing device is not reactivated until the powdered image corresponding to the latent image has been transferred to a sheet of paper. Beginning at the instant when the erasing device 22 has been reactivated, a new latent image can be recorded on the drum 11; this recording is effected either by displacing the carriage 3 incrementally beginning at its limit position LD in the direction of its limit position LG, or by first putting the carriage into its limit position LG and then displacing it incrementally in the direction of its limit position LD.
Referring to FIGS. 1 and 3, the structure of the device for applying particles that permits forming the powdered image corresponding to the latent image recorded on the drum in the course of six successive revolutions of the drum will now be described. As can be seen in FIG. 1, the applicator device includes on the one hand a transport element 23 that picks up developer particles in the reservoir 17 so as to place them in the vicinity of the surface 12 of the drum, and on the other hand includes a fixed deflector 24 disposed between the transport element 23 and the drum 11 for gathering the particles transported by the element 23 and applying them to the surface of the drum.
In the example described, the transport element 23 comprises a magnetic cylinder the axis of rotation 25 of which is parallel to the shaft 13 of the drum 11 and can rotate in two bearings (not shown), with which the side faces 26 and 27 of the reservoir 17 are respectively provided.
The deflector 24, which is shown on a large scale in FIG. 3, is a part made of a nonmagnetic material and fixed to the two side faces of the reservoir 17. This part has one plane face 40 limited by a first and second edge 41 and 42, which are parallel to the axes 13 and 25. The deflector 24 is disposed such that on the one hand, its first edge 41 is located in the immediate proximity of the surface 12 of the drum and on the other hand, if the generatrix of the drum where the plane P of the face 40 intersects the surface 12 of the drum is designated as G, this plane P forms an angle A with the plane normal to G at the surface of the drum, the size of the angle being less than 45°. The distance by which this generatrix G is separated from the first edge 41 of the deflector is always very small. In the example described, this distance is substantially equal to 1 mm. In the example described, the width of the face 40 is on the order of 1 cm.
The transport element 23 has a direction of rotation, indicated by the arrow R, such that it drives the developer particles toward the face 40 of the deflector. The second edge 42 of the deflector is located virtually in contact with the surface of the transport element, such that the particles that are driven by this transport element are for the most part prevented from moving onward by the deflector 24, so that they accumulate in a spout 43 of substantially prismatic shape defined by the cylindrical surface 12 of the drum and the face 40 of the deflector 24. The direction of rotation F of the drum 11 is such that, when the quantity of particles accumulated in the spout 43 is sufficient to reach the first edge 41 of the deflector, the particles in proximity with the surface 12 of the drum are driven in the direction of the generatrix G, which arbitrarily comprises the apex of the spout 43. Some of the particles are then applied to the magnetized zones 15 of the drum. The particles thus driven by the drum are not prevented from moving onward by the deflector 24, because the deflector does not touch the surface of the drum, so that it consequently leaves a narrow opening between its first edge 41 and the drum, the width of the opening nevertheless being sufficient to permit developer particles driven by the drum to exit from the spout 43. The developer particles applied to the magnetized zones of the drum and exiting from the spout 43 continue to adhere to these zones and thus make the image that is to be printed visible, while the particles that emerge from the spout 43 without being retained on the drum drop back into the reservoir 17 Since the distance separating the edge 41 of the deflector and the surface 12 of the drum is quite short, the number of particles that also emerge from the spout 43 is relatively low, such that the particles which are not retained by the drum and hence drop back into the reservoir 17 are not very numerous and so do not form clouds of particles capable of polluting the machine.
According to the invention, the applicator device 16 also includes a squeegee 45, as shown in FIG. 1, which is placed between the deflector 24 and the transfer station H and is actuated by an electromagnet EA in such a manner as to be put into either a first position, in which it is in contact with the surface 12 of the drum and hence stops the travel of the developer particles which, emerging from the spout 43, remain pressed against this surface, or a second position, in which it is spaced apart from the surface and thus allows the particles that have been deposited on it to move on as the drum rotates.
The particles which are stopped by the squeegee 45 when it is in its first position finally drop back into the reservoir 17. However, to prevent some of the particles from sliding between the squeegee and the drum and thus continuing to adhere to the surface of the drum, the squeegee must be pressed against this surface with a sufficient force, the value of which also depends on the size of the particles and on the force that holds the particles on the surface of the drum.
In an advantageous embodiment which is shown in FIG. 3, the squeegee is in the form of a flexible blade including on the one hand a fixed portion 46, intended to permit the blade to be attached firmly to a fixed transverse plate 47 that is part of the reservoir 17, and on the other hand a free portion 48 terminated by an edge 49 that is parallel to the axes 13 and 25 and is pressed against the surface 12 of the drum; this edge thus comes to contact the surface along a generatrix K of the drum. The flexible blade 45 is positioned such that its terminal portion, which is near the edge 49, forms an angle t, the value of which is between 10° and 45°, with the half-tangent T to this surface 12 at the point of contact K and oriented in the direction of displacement of the drum.
To assure that practically none of the particles that have been stopped by the blade will slide between the blade and the surface of the drum, the blade must be pressed against the surface with a sufficient force. For the type of particles used in the example described, it has been found that the force P exerted per unit of length on the edge 49 of the blade in contact with the drum must be equal to at least 2.5 N/dm. If b* is the length, a the width and e the thickness of the free portion 48 of the blade (this length b corresponding to the length of the edge 49 of the blade), then it is known that when the blade is subjected to a flexion such that the edge 49 of the blade is displaced by a distance f with respect to its original position, the force P that is exerted per unit of length on the edge 49 can be expressed as follows: ##EQU1##
E is the value of the modulus of elasticity of the material comprising the blade. It can thus be seen that if a material having sufficient elastic properties is selected for the blade, the values for the width a, the thickness e and the flexion f that must be adopted to obtain a force P the value of which is equal to at least 2.5 N/dm can be determined.
In practice, it is arranged that the amplitude of the flexion f undergone by the flexible blade is equal to at least one-half the width a of the blade; this arrangement permits the flexible blade, if it is made of one of the materials conventionally selected for elastic blades, to remain within the range of elastic deformation. However, the hardness of the material used to make the flexible blade must not be very great, so as not to risk deterioration of the surface of the drum against which the blade is pressed. It has been found that in order for the flexible blade to remain within the limit of elastic deformation and not to cause any degradation of the surface of the drum, the material used to make the blade must have a modulus of elasticity E at least equal to 300 daN/mm 2 and a hardness equal to no more than 600 Vickers. The flexible blade may for example be a blade of polyethylene terephthalate, conventionally known as Mylar (registered trademark), which has a modulus of elasticity equal to virtually 480 daN/mm 2 ; the free portion of this blade has a width a practically equal to 8 mm, and a thickness e practically equal to 0.2 mm. The force P exerted per unit of length on the edge 49 of the blade, when the blade undergoes a flexion f equal to one-half the width a of the blade or in this case 4 mm, accordingly has the following value: ##EQU2##
The flexible blade can also be a blade of stainless steel having a modulus of elasticity equal to virtually 25,000 daN/mm 2 , the free portion of this blade having a width a practically equal to 8 mm and a thickness e practically equal to 0.05 mm. The force P exerted per unit of length on the edge 49 of the blade, when the blade undergoes a flexion f equal to one-half the width a of the blade or in this case 4 mm, accordingly has the following value: ##EQU3##
In order that the flexible blade will not undergo excessively rapid wear because of its friction on the surface of the drum, the force with which the blade is pressed against the surface must not be excessively high. Experiments have shown that to obtain moderate wear of the blade, the force P exerted per unit of length on the edge 49 of the blade must not in practice exceed the value of 20 N/dm.
As can be seen in FIG. 3, the applicator device 16 also includes an actuating device making it possible to move the squeegee 45 away from the surface 12 of the drum and thus to allow the particles that have been applied to remain on this surface, with the aid of the deflector 24.
This actuation device is embodied by a rod 50 disposed parallel to the axes 13 and 25 and capable of pivoting in two bearings (not shown) fixed to the side faces 26 and 27 of the reservoir 17, and a lever 51 mounted on one of the ends of the rod 50, the arm of the lever being pivoted at the end of a sliding rod 52 integral with the movable armature of an electromagnet EA, which in turm is fixed to one of the side faces of the reservoir 17. When the electromagnet EA is not excited, the lever 51 occupies a first position, its position of repose, which is shown in dashed lines in FIG. 3. On the other hand, when the electromagnet EA is excited, the lever 51 occupies a second position or working position shown in dot-dash lines in FIG. 3. In the exemplary embodiment shown in FIG. 3, in which the squeegee 45 comprises a flexible blade, the rod 50 is machined in such a way that in its middle portion, over a length equal at least to the length of the blade, it has a plane face 53, which as seen in FIG. 3A passes through the axis 54 of the rod and is limited by two edges 55 and 56. This rod 50 is positioned such that its middle portion, which is accordingly of semi-cylindrical shape, is located between the free portion 48 of the blade 45 and the surface 12 of the drum, and such that when the lever 51 is in its position of repose, the edge 55 of this middle portion is located as close as possible to this free portion 48, without contacting it, as can be seen in FIG. 3A. Under these conditions, this middle portion of the rod 50, when the lever 51 is in the position of repose, does not threaten to change the value of the force with which the edge 49 of the blade 45 is pressed against the surface of the drum.
If the electromagnet EA is now excited, the lever 51 assumes its working position and pivots the rod 50 by an angle w in the direction indicated by the arrow in FIG. 3A.
In this case, the middle portion of the rod occupies a position that as shown in dot-dash lines in FIG. 3A forms an angle w with the original position, and the edge 55 of this middle portion, now pressed against the free portion 48 of the blade 45, causes this free portion to deflect to an increasing extent and thus move away from the surface 12 of the drum.
Turning now to FIG. 4, the control circuit for exciting the electromagnet EA will now be described. This circuit includes manual control contacts and relay contacts provided for use under the conditions that will now be described. In FIG. 4, each relay contact is identified by the same reference numeral as that of the coil it controls, but is preceded by the letter C. A contact, normally closed when the relay coil that it controls is not excited, is represented in this drawing figure by a black triangle. The relays shown in this drawing figure are normally supplied with direct current between two terminals + and -; the negative terminal (-) is connected to ground.
In order to describe the function of the circuit shown in FIG. 4, it is assumed that each of the heads of the recording device has completed recording information on the first five of the six tracks with which it is associated, and this recording has been performed in the course of five successive revolutions of the drum 11. In the course of the fifth revolution the magnetic heads T1, T2, T3, . . . , Tn have been placed facing the tracks P15, P25, P35, . . . , Pn5, respectively, so that the electrical signal that at the end of the fifth revolution appears at the output of the cell PH causes the displacement of the carriage 34 by one increment toward the right. The effect of this displacement is first to move the heads T1, T2, T3, . . . , Tn to face the tracks P16, P26, P36, . . . , Pn6, respectively and thus to allow these tracks to be recorded in the course of a sixth revolution of the drum 11, and on the other hand depresses a contact KD, which as shown in FIG. 2 is disposed so as to be actuated by the carriage 34 when the carriage is put in its limit position LD. As will be understood with reference to FIG. 4, depression of the contact KD causes a positive voltage to be applied to the input of a drifter amplifier AD; this input is in effect connected to the positive terminal via the contact KD.
The drifter amplifier is designed to furnish a single positive pulse to its output each time its input is connected to a positive potential. The pulse that appears at the output of this drifter amplifier AD is applied to the input of a time-lag element R1, which in response to receiving this pulse furnishes a delayed pulse to its output. The time lag of this element R1 is arranged such that this delayed pulse appears at the output of this element only when the portions of the drum surface that move past the heads T1, T2, T3, . . . , Tn at the instant when these heads have been moved to face the tracks P16, P26, P36, . . . , Pn6 are at the point of passing beneath the blade 45. The delayed pulse that then appears at the output of the element R1 is applied first to the input of a second time-lag element R2 and second to the electromagnet EA and to a relay B02
The relay B02, when excited, then closes its contact CB02 and completes a holding circuit for itself and for the electromagnet EA, via a normally closed contact CB01 and the contact CB02. The electromagnet EA when excited actuates the rod 52, thus moving the lever 51 to the working position, with the effect of moving the blade 45 away from the surface 12 of the drum. Under these conditions, this blade, which until now has pulled away the developer particles that on emerging from the spout 43 remained applied to the surface of the drum, now allows these particles to remain on the surface, such that the particles can reach the transfer station H, where they are then transferred to a sheet of paper 19 that at that moment is engaged between the drum 11 and the transfer roller 20. The time lag of the element R2 is arranged such that in response to an electrical pulse applied to its input, this element furnishes a delayed pulse at its output at the end of a time substantially equal to the time that the drum takes to accomplish one revolution. More precisely, this delayed pulse appears at the output of R2 at the moment when the powder image corresponding to the latent image formed in the course of six successive revolutions of the drum has completely passed before the blade 45. This delayed pulse is applied to a relay B01, which upon being excited for a short moment instantaneously opens its contact CB01. The opening of the contact CB01 has the effect of de-exciting the B02 and the electromagnet EA. Consequently, the de-excited relay B02 opens its holding contact CB02, while the electromagnet EA ceases to hold the blade 45 spaced apart from the surface of the drum.
Beginning at that instant, the developer particles that after emerging from the spout 43 remain applied to the surface of the drum are prevented from passing on by the blade 45 and then drop back into the reservoir 17.
The printing machine shown in FIG. 1 may be designed such that recording of a latent image on the drum takes place only when the carriage 34 is displaced incrementally from its limit position LG in the direction of its limit position LD. In this case, when the carriage 34 has arrived at its limit position LD at the end of its incremental displacement, then as soon as the recording of information on tracks P16, P26, P36, . . . , Pn6 has been completed, the carriage is rapidly returned to its limit position LG, to permit recording of a new latent image on the drum; the excitation of the heads of the recording device 14 is interrupted for the entire duration of the return motion of the carriage.
The machine shown in FIG. 1 may also be designed such that recording of a latent image on the drum takes place when the carriage 34 is displaced incrementally from either its limit position LG or its limit position LD. In this case, when the carriage 34 has arrived at its limit position LD at the end of its incremental displacement, then as soon as recording of the information on tracks P16, P26, . . . , Pn6 has been completed, the carriage is moved incrementally to its limit position LG, while a new latent image is formed on the drum. During the first five of the six revolutions of the drum required for forming this new image, the electromagnet EA is not excited, so that none of the developer particles that emerge from the spout 43 can arrive at the transfer station H. Once the carriage 34 reaches its limit position LG in the consequence of its incremental displacement and thus places the heads facing tracks P11, P21, . . . , Pn1, the electromagnet EA is excited, at the instant when the portions of the surface of the drum that pass beneath these heads at the instant when the carriage arrives at its position LG are on the point of passing beneath the blade 45. The excitation of the electromagnet at this instant can be advantageously triggered by a contact KG, which as shown in FIG. 2 is disposed in such a manner as to be actuated by the carriage 34 at the moment the carriage reaches its limit position LG; the contact KG is mounted such that it bypasses the terminals of the contact KD, as shown in FIG. 4.
Definitively, regardless of the mode adopted for forming the latent images on the drum, provided that the formation of each of the images is performed in the course of a plurality of successive revolutions of the drum (that is, at least two revolutions), it is understood that the formation of the powdered image corresponding to the latent image is undertaken only in the course of the last of these revolutions; the powdered image is transferred immediately after that to a sheet of paper. Under these conditions, the transfer roller 20 is not threatened with being spotted by developer particles during the periods when no sheet of paper is engaged between the roller and the drum 11. | The invention relates to a device for intermittently applying particles of a powdered developer to the recording surface of a magnetographic printer. This device includes a reservoir (17) containing developer particles, a transport element (23) for placing these particles in the vicinity of the surface of a magnetic drum (11), a deflector (24) disposed between this transport element and the drum to apply the particles to the drum surface, and a squeegee (45) disposed between the deflector and the transfer station (H), and actuated by an electromagnet (EA) for selectively pulling away the particles that have been deposited on the drum surface. The invention is applicable to magnetographic printers. | 8 |
CROSS REFERENCE TO RELATED APPLICATION(S)
This is a continuation of application Ser. No. 09/438,253 filed on Nov. 12, 1999, now U.S. Pat. No. 6,664,969 which is hereby incorporated by reference herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a method and apparatus for remotely accessing, interacting and monitoring a computer system independent of the operating system, and more particularly to remotely displaying graphics-mode display data of the accessed computer system.
2. Description of Related Art
Advances in computing technology have caused a shift away from centralized mainframe computing to distributed computing using multiple personal computers (PCs) connected to a network. The network typically includes one or more server class personal computers to handle file, print and application services, which are common to all the connected PCs. Therefore, the server becomes an important resource which the entire network depends upon.
Oftentimes, businesses may require more than one server. Networks may demand isolation for security reasons. Networks may be logically subdivided for performance or practical reasons. In particular, networks may be in different geographic locations. However, oftentimes the maintenance and management of the servers falls onto a single group or person, called a network administrator. In these cases where the managed server is in an inconvenient location, it is desirable for the network administrator to be able to monitor the health of the managed server without traveling to its location.
In the past, the local network administrator operating from a remote management computer could telephonically connect into the operating system of a managed server to monitor its health using a conventional communications package such as PC Anywhere or ProComm. This method required a third communications computer to be attached to the network. Typically, a connection would first be established from the remote management computer to the communications computer attached to the network of the server. If the server was operating, the network administrator would be prompted for a login password to access network resources, including the server. If the server was down, only the communications computer could be accessed (providing that PC had its own modem). After the administrator logged into the network, a server console utility, such as RCONSOLE, could be executed to gain access to the server. Because many times the server would be down, this method had limited usefulness. Additionally, only limited information was provided, since the server would have to be operating before the server console utility would operate.
Network administrators also have used products such as Compaq's Insight Manager. This software product is loaded by the operating system to allow users to connect to the operating system through a dedicated modem using (remote access service) RAS/PPP (point to point) protocols. This method also allows insight into the operating system, but only after the server is operating.
To help in this regard, an accessory known as Compaq Server Manager R was developed. This accessory was essentially a personal computer system on an add-in board adapted to interact with the host server. Server manager R included a processor, memory, modem and software to operate independently of the server to which it was installed. To monitor the server from a remote location, the network administrator would dial into the server manager R board and establish a communications link. If a connection was established, the processor of server manager R would periodically acquire access to an expansion bus of the server to read the contents of the server video memory. The processor would then send the contents ***[text or graphics]*** to the local computer via the communications link. A separate power supply was provided to the server manager R board so that it would operate even while the server was booting or powered down. Although the functionality provided by the server manager R board was desired, because it was essentially a second computer, the high cost of this solution limited its success.
Later, a more integrated approach was taken with a device known as the integrated remote console (IRC) device. This device would connect to a conventional peripheral component interconnect (PCI) bus to monitor video activity. As PCI transactions were passed to a video controller also attached to the PCI bus, the IRC device would snoop the video transactions for the purpose of encoding the screen activity and sending the encoded data to a remote computer. IRC worked best with text-mode operating systems. If the server was running a graphical operating system, such as Microsoft Windows, the IRC device would cease to transmit information when the graphics mode was entered upon boot-up. Thus, although the IRC device was very useful for text-mode operating systems and to monitor graphical operating systems prior to entrance into graphics mode, a more complete solution was desired.
SUMMARY OF THE INVENTION
In one embodiment of the present invention, a managed server includes a video graphics controller having a frame buffer. The frame buffer may be periodically read to determine if the contents of the frame buffer has changed. Changes are transmitted to a remote console in communication with the managed server.
The frame buffer may be divided into a number of blocks with each block having a unique number based on its contents. The unique numbers may be stored in a buffer. As the blocks are periodically read, new unique values are calculated and compared to the previously calculated unique values to determine if the blocks have changed. The changed blocks are transmitted to the remote console via a communications link.
Each pixel contained in the frame buffer may be condensed into a smaller 6-bit value before calculating the unique value and transmitting to the remote console. Furthermore, the blocks may be compressed by using a run length-encoding algorithm. If two more blocks are similar, the first block is transmitted followed by a command indicating the number of times to repeat the block.
Instead of reading each block of the frame buffer, a fraction of the frame buffer may be read, such as every fourth block. Each pass may read a different fraction of the frame buffer until the entire frame buffer has been read. If changes are detected during a pass, the blocks surrounding the changed block may be “marked” for accelerated reading (i.e. read immediately or on the next pass). The “marks” are cleared once the blocks have been checked.
The blocks of the frame buffer comprise rows and columns. Periodically, such as at the end of each row, the video graphics controller is checked for configuration changes. Possible changes include changes to screen resolution, color depth and color mode. If changes are detected, commands are developed to communicate the changes to the remote console. Changes for a pointing device, including position, shape and size are handled similarly.
BRIEF DESCRIPTION OF THE DRAWINGS
The following drawings form part of the present specification and are included to further demonstrate certain aspects of the present invention. The invention may be better understood by reference to one or more of these drawings in combination with the detailed description of specific embodiments presented herein.
FIG. 1 is a connection diagram of a managed server and a remote management console according to a preferred embodiment;
FIG. 2 is a block diagram of the managed server according to the preferred embodiment;
FIG. 3 is a block diagram of the remote management board of FIG. 2 according to the preferred embodiment;
FIG. 4 is a block diagram of the managed server according to an alternative embodiment;
FIG. 5 is a block diagram of the reading, color converting and hashing processes according to the preferred embodiment;
FIG. 6 is a block diagram of the compressing and transmitting processes according to the preferred embodiment;
FIGS. 7A-C are flow diagrams illustrating the processes of FIGS. 5 and 6 ;
FIGS. 8A-C are flow diagrams illustrating flushing the compression buffer;
FIG. 9 is a flow diagram illustrating the block compression process according to the preferred embodiment;
FIGS. 10A-C are flow diagrams illustrating the processes of FIGS. 5 and 6 according to the preferred embodiment; and
FIGS. 11A-B are block diagrams illustrating pixel block sampling and marking methods according to the preferred embodiment.
DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
The following patents or patent applications are hereby incorporated by reference:
U.S. Pat. No. 5,898,861, entitled “Transparent Keyboard Hot Plug” by Theodore F. Emerson, Jeoff M. Krontz and Dayang Dai;
U.S. Pat. No. 5,790,895, entitled “Modem Sharing” by Theodore F. Emerson and Jeoff M. Krontz; and
U.S. patent application Ser. No. 08/733,254, entitled “Video Eavesdropping and Reverse Assembly to Transmit Video Action to a Remote Console” by Theodore F. Emerson, Peter J. Michaels and Jeoff M. Krontz, filed Oct. 18, 1996.
Referring first to FIG. 1 , there is illustrated a managed server S connected to a remote console (“C”) by a network N. The managed server S includes a central processing unit (“CPU”) 2 housing processing, memory, communications, interface, and other circuitry as described more fully below, and may be connected to a monitor 4 . The remote console C also includes a CPU 6 and a monitor 8 . The managed server S includes special circuitry and software for capturing, analyzing, compressing and transmitting video activity to the remote console C independent of an operating system (“OS”). The special circuitry and software operate without regard to the existence or type of OS present on the managed server S. Therefore, the present invention is useful for accessing, interacting and monitoring the managed server S from the remote console C even before its OS has been loaded. More specifically, the video displayed on monitor 4 is capable of being viewed on monitor 8 independent of the OS.
The network N can be any sort of network capable of transmitting data between two devices. Without limitation, some examples of networks include: a local area network, a wide area network, a hardwired point-to-point connection, a point-to-point connection over a telecommunications line, a wireless connection, and an internet connection.
Although the managed server S shown is preferably of an International Business Machines. (IBM) PC variety, the principles of the present invention are equally applicable to other computer platforms or architectures, such as those manufactured by IBM, Apple, Sun and Hewlett Packard. Additionally, the managed server S could be one architecture and the remote console C could be another. For example, the managed server S could be a x86 architecture machine computer running Microsoft Windows NT OS and the remote console C could be a Sun workstation running Solaris OS.
In the operation of the present invention, video data is captured, analyzed, compressed and transmitted to the remote console C by special circuitry and software in the managed server S. The remote console C includes special software for receiving and interpreting the transmitted data in order to reproduce on its own monitor 8 the video data displayed on the managed server monitor 4 . The transmitted video data is encoded with special commands to permit the remote console C to interpret the data stream.
Now referring to FIG. 2 , there is illustrated a block diagram of the managed server S according to the preferred embodiment. To provide sufficient processing power, the managed server S includes one or more processors 10 , such as a Pentium II Xeon processor manufactured by Intel Corporation. Each processor 10 may include a special non-maskable interrupt, called the system management interrupt (“SMI”), which causes the processor to operate in a special system management mode (“SMM”) independent of the operating system. This functionality is fully explained in literature available from Intel.
The processor 10 is coupled to a north bridge 12 , such as an Intel 82451NX Memory and I/O Bridge Controller (MIOC). The north bridge includes a memory controller for accessing a main memory 14 (e.g. dynamic random access memory (“DRAM”)), and a peripheral component interconnect (“PCI”) controller for interacting with a PCI bus 16 . Thus, the north bridge 12 provides the data port and buffering for data transferred between the processor 10 , memory 14 , and PCI bus 16 .
In the managed server S, the PCI bus 16 couples the north bridge 12 to a south bridge 18 and one or more PCI slots 20 for receiving expansion cards (not shown). The south bridge 18 is an integrated multifunctional component, such as the Intel: 82371 (a.k.a. PIX4), that includes a number of functions, such as, an enhanced direct memory access (“DMA”) controller; interrupt controller; timer; integrated drive electronics (“IDE”) controller for providing an IDE bus 22 ; a universal serial bus (“USB”) host controller for providing a universal serial bus 24 ; an industry standard architecture (“ISA”) bus controller for providing an ISA bus 26 and ACPI compliant power management logic. The IDE bus 22 supports up to four IDE devices, such as a hard disk drive 28 and a compact disk read only memory (“CD-ROM”) 30 . The universal serial bus 24 is connected to a pair of USB connectors 32 for communicating with USB devices (not shown).
The ISA bus 26 couples the south bridge 18 to a multifunction input/output (I/O) controller 34 and a basic input/output system (BIOS) ROM 36 . The multifunction I/O controller 34 , such as a Standard Microsystems Corporation FDC37C68x, typically includes a number of functions, such as a floppy disk drive controller for connecting to a floppy disk drive 42 ; a keyboard controller 38 for connecting to a keyboard and a pointing device; a serial communications controller for providing at least one serial port 44 ; and a parallel port interface for providing at least one parallel port 46 . Alternative multifunction input/output (I/O) controllers are manufactured by National Semiconductor and WinBond.
Further attached to the PCI bus 16 via one of the PCI slots 20 is a remote management board 50 . The remote management board 50 connects to the keyboard controller 38 , the network N, a keyboard 52 and a mouse 54 to provide functionality for accessing, interacting and monitoring the managed server S from the remote console C as will be more fully described below.
The functions described above may alternatively be implemented in separate integrated circuits or combined differently than described above without departing from the concept of the present invention.
Turning now to FIG. 3 , there is illustrated a block diagram of the remote management board 50 . Coupled to the PCI bus 16 is a processor 100 , such as an Intel i960RP. The Processor 100 includes a PCI-to-PCI bridge unit for bridging PCI bus 16 (hereinafter primary PCI bus 16 ) to a secondary PCI bus 102 . Alternatively, a separate processor and bridge could be used. The processor 100 also includes a secondary PCI bus arbitration unit, an integrated memory controller and three direct memory access (“DMA”) channels. The processor 100 operates independently of the processor 10 , and therefore, includes a memory controller for accessing memory (e.g. read only memory 106 and random access memory 108 ) over a local bus 104 in order to boot its own operating system, such as Wind River System's IxWorks RTOS. One or more communications devices are also connected to the local bus 104 , such as a network interface controller (“NIC”) 110 and a modem 112 . Other communications devices can be used as required by the network type.
The secondary PCI bus 102 is seen by the processor 10 as a logical extension of the primary PCI bus 16 . Further attached to the secondary PCI bus 102 is a video graphics controller 114 a and a remote management controller 116 a . The video graphics controller 114 a is an integrated video graphics controller, such as an ATI technologies Rage IIC or XL, that supports a wide variety of memory configurations, color depths and resolutions. Connected to the video graphics controller 114 a is a frame buffer 118 a (e.g. synchronous DRAM) for storing video graphics images written by the processor 10 for display on the monitor 4 .
The remote management controller 116 a includes circuitry for snooping configuration transactions between the processor 10 and the video graphics controller 114 a to determine configuration and mode information, such as whether the video graphics controller is in text or graphics mode. The remote management controller 116 a also includes circuitry to route keystrokes to the keyboard controller 38 from either the local keyboard 52 or from the remote console C (via the modem 112 a or NIC 110 ). This keyboard functionality is more fully explained in U.S. Pat. No. 5,898,861, entitled “Transparent Keyboard Hot Plug.”
In the operation of the remote management board 50 , the processor 100 may periodically read the video graphics data from the frame buffer 114 a in order to determine whether the data has changed. If the data has changed, the processor 100 will compress the video graphics data and transmit the data to the remote console C via one of the communications devices (i.e. modem 112 a or NIC 110 ). The remote console C will decompress and decode the data stream and display it at the remote console C for viewing by a user.
Now referring to FIG. 4 , there is illustrated a first alternative embodiment of managed server S offering a more integrated and less expensive solution than that described in FIGS. 2 and 3 . Since many of the components are the same as in FIG. 2 , only the differences will be discussed.
Attached to the PCI bus 16 is the remote management controller 116 b and the video graphics controller 114 b . The remote management controller 116 b is connected to the keyboard controller 38 and the keyboard 52 for routing keystrokes based on whether the remote console C is operational. Modem 112 b is connected to the ISA bus 26 in a conventional manner for use by standard communications programs. However, in this embodiment, the modem 112 b may be claimed by the remote management controller for exclusive use with the remote console C. Further details on modem sharing can be found in U.S. Pat. No. 5,790,895, entitled “Modem Sharing.” Although only a modem is shown, it is understood that any type of communications device could be used.
In this alternative embodiment, an independent processor, such as the processor 100 is not provided. Instead, the system management mode of the processor 10 is utilized to provide a “virtual” processor. The remote management controller 116 b is configured to periodically interrupt the processor 10 with a system management interrupt, thereby causing processor 10 to enter system management mode and function as a “virtual” processor.
When functioning as a “virtual” processor, the processor 10 will read the frame buffer 118 b in order to determine whether the video graphics data has changed. If the data has changed, the processor 10 will compress the video graphics data and transmit the data to the remote console C via a communications device (i.e. modem 112 b ).
Thus in this first alternative embodiment, processor overhead is sacrificed for a better-integrated solution. A second alternative embodiment involves using the “virtual” processor 10 for special functions and the processor 100 for the remaining processing. For example, if a communications device was not provided on the remote management board 50 but instead was attached to the ISA bus 26 or PCI bus 16 , the system management mode of processor 10 can be used to handle communications between the managed server S and the remote console C. As another variation, the processor 10 can be configured to trap on writes to the frame buffer 118 b to assist in determining when video graphics data has changed. As a further variation, if the video graphic controller were located on an accelerated graphics port (“AGP”), the processor 10 could be configured to trap on all writes to the frame buffer 118 b to assist in determining when the video graphics data has changed.
For purposes of simplicity, the remaining description will correspond with the preferred embodiment, but it is understood that the processes can be adapted according to the first and second alternative embodiments.
Reading and Analyzing
Now turning to FIG. 5 , there is illustrated a flow diagram of the reading and analyzing processes according to the preferred embodiment of the present invention. Analyzing video graphics data for change starts with dividing the video graphics data of the frame buffer 118 a/b into manageable blocks 200 , such as 16×16 pixel blocks. For example, a 1024×768 display resolution would result in 48 rows and 64 columns for a total of 3072 blocks. Initially, each of the 3072 blocks is transmitted to the remote console C. Thereafter, a given block is only transmitted if it has changed as compared to a previously transmitted block.
Generally, changes in a given block's data are determined by comparing the block's previously transmitted data to the block's current data. This determination is simplified in the preferred embodiment by comparing hash codes calculated for each block 200 . A hash code is a unique number mathematically calculated by performing a hashing algorithm 204 , such as a 16-bit cyclic redundancy check or other algorithm resulting in a unique number. The first time the block 200 is hashed the unique number is stored in a hash code table 202 formed in memory 108 . Thereafter, each time the block is read and hashed another unique number is calculated. If the newly calculated number matches the number stored in the hash table 202 , the block 200 has not changed. If the numbers don't match, the block 200 has changed and is transmitted to the remote console C.
The process is further simplified and data transmission is more efficient if the pixel values are condensed into a smaller number, such as 6-bits, before performing the hashing algorithm. For this purpose a color converting algorithm 206 is provided, as described in Table I for developing a 6-bit, zero-padded, color pixel block 208 in memory 108 . For color values 8-bits or less a color lookup table is used and for pixel values greater than 8-bits a mathematical calculation is applied to produce a 6-bit value. For example, a 24-bit color value of 0xd5aad5h will result in a 6-bit value of 0x00101010b. The color lookup tables are based on the color lookup tables provided with the video graphics controller 114 a/b.
Bit shifting the full color values may be used an alternative to the above color condensing method. Although using the above-described color condensing technique is preferred, it is understood that full color values could be used with proper transmission bandwidth without changing the principles of the present invention.
It is noted that if the first alternate embodiment is employed, the 6-bit color code table 208 and the hash code table 202 would be formed in system management memory of the “virtual” processor 10 .
TABLE I
INPUT
COLOR CONVERSION
OUTPUT
1 bit color
color lookup table
6-bit RGB color value
2 bit color
4-bit color
8-bit color
15-bit color
R*3/31, G*3/31, B*3/31
6-bit RGB color value
16-bit color
R*3/31, G*3/63, B*3/31
6-bit RGB color value
24-bit color
R*3/255, G*3/255, B*3/255
6-bit RGB color value
Compressing and Transmitting
Referring now to FIG. 6 , there is illustrated a flow diagram of the compression and transmission processes according to the preferred embodiment of the present invention. A pixel block 200 is first converted to a 6-bit color pixel block 208 , as noted above. Then the 6-bit color pixel block 208 may be compressed by a compression function 210 and temporarily stored in a transmit buffer 212 . At least at the end of each row, a transmit packet 214 is developed having a conventional header and footer as required by the particular network transport scheme. For example, a transmission control protocol/internet protocol (“TCP/IP”) header and footer may be appended to the data for transmission over a local or wide area network to the remote console C. In the development of the transmit packet 214 , the video graphics controller is checked for configuration changes and the mouse is checked for positioning changes. Any changes are also appended to the transmission packet 214 . Video graphics changes may include: changes in resolution, mode, and color depth. Mouse changes may include: positioning, and cursor shape and size. For example, if the resolution of the video graphics controller was changed, the change would be appended to the transmission packet 214 and the change would take effect at the remote console C beginning with the next row.
Compressing the data is accomplished using run length encoding (RLE) techniques. The image compression algorithm 210 simply looks for long runs of the same pixel value and encodes it into a single copy of the value and a number representing the number of times that value repeats. Since each pixel block 200 is represented by a unique number (hash code) the same encoding can be used to look for long runs of the same pixel block 200 . A repeated block count 216 tracks the number of times a block is repeated. A repeated byte count 218 tracks the number of times a byte is repeated either within a block or across blocks. A repeated data buffer 220 holds the repeated byte as it is compared to subsequent bytes.
Other graphics or multimedia compression techniques could be used instead of the RLE compression function 210 , such as motion picture expert group (MPEG) encoding, joint photographic experts group (JPEG) encoding, and graphics interchange format (GIF) encoding. Additionally, these alternative compression techniques may operate better on full-color values instead of the 6-bit condensed color values created by the color converter 206 .
Data Transmission Scheme
To access, interact and monitor the managed server S, the remote console C initiates a telnet session with the remote management board 50 . If the managed server S is operating in a text display mode, the remote management board 50 will send a text data stream using standard telnet formatted commands to the remote console C, as described in U.S. patent application Ser. No. 08/733,254, entitled “Video Eavesdropping and Reverse Assembly to Transmit Video Action to a Remote Console.” If the managed server S is operating in a graphics display mode, the remote management board 50 will encode the graphics data using one of two types of special commands: an american national standards institute (“ANSI”) escape sequence formated command or a special telnet formated command.
The special commands are interpreted by software running on the remote console C. The remote console C communicates its ability to interpret the special commands before the remote management board 50 will send graphics data. If the remote console is a conventional telnet client, the graphics data will not be sent, but the remote management board 50 will still send text mode data. Thus, even if the special client software is not available at a remote console, any telnet session is usable for text mode exchanges.
Software running on the remote console is configured to interpret the special commands and escape codes as described below. A command and data typically follow the telnet escape code to complete a data stream. The special telnet commands are defined below in Table II.
TABLE II
COMMAND
USAGE
DESCRIPTION
Move
0xff 0xe5 X Y
Moves the pen to a new x-y coordinate. X and Y are
8-bit values representing the row and column to
place the pen.
Repeat8
B 0xff 0xe6 R8
Repeats a byte of data B up to 255 times. B and R8 are
8-bit values. R8 specifies the number of repeats.
Repeat16
B 0xff 0xe7 R16
Repeats a byte of data B up to 65535 times. B is
an 8-bit value and R16 is a 16-bit value. R16
specifies the number of repeats.
RepeatBlk8
0xff 0xe8 B8
Repeats the previous block up to 255 times. B8
is an 8-bit number specifying the number of
repeats.
RepeatBlk16
0xff 0xe9 B16
Repeats the previous block up to 65535 times.
B16 is an 16-bit number specifying the number
of repeats.
Special ANSI escape codes are sent only if the client used by the remote console C is ANSI compliant. The special ANSI escape codes are listed in Table III.
TABLE III
COMMAND
USAGE
DESCRIPTION
Graphics mode
esc] W ; H ; B g
Enables graphics mode at the remote console.
W is the screen width encoded in ASCII. For
example, 640-pixel width would be 545248h. H
is the screen height encoded in ASCII. B is a
ASCII character specifying the number of bits
per pixel color (i.e. 2 or 6). Lowercase g is the
command.
Text mode
esc] G
Enables text mode. Uppercase g is the
command.
Pointer Position
esc] X ; Y h
Provides an absolute address of the mouse
pointer relative to the top left corner of the
screen. X is an ASCII encoded set of numbers
representing the number of pixel positions to the
right. Y is an ASCII encoded set of numbers
representing the number of pixel positions down
from the top. Lowercase h is the command.
Pointer Shape
esc] M C1 C2 D
Specifies the shape of the pointer. Uppercase m
is the command. C1 and C2 are 6-bit, binary, 0-
padded numbers representing a color value. D is
a 1024 byte data stream representing a 64 × 64
pixel pointer image. Each 2-bit pixel value
indicates one of four ways the pixel should be
developed: using C1, using C1, XOR with
screen or transparent.
Operational Description
Turning now to FIGS. 7A-C , there is illustrated a flow chart of the methods related to reading, analyzing, compressing and transmitting video graphics data to the remote console C. According to the preferred embodiment, most of these steps are performed by the processor 100 , but alternative embodiments may use the processor 10 , as noted above.
Configuration cycles to the registers of the video graphics controller 114 a are captured by the remote management controller 116 a . Hence, the configuration of the video graphics controller, including resolution, color depth and color mode are readily available to the processor 100 .
When the remote console C initiates a communications link with the remote management board 50 , the processor is alerted to start sending video graphics data to the remote console C.
The process starts at a step 300 where the processor 100 reads one or more video graphics blocks 200 from the frame buffer 118 a . Because the processor 100 and the video controller 114 a are on a secondary PCI bus 102 , the read cycles do not significantly impact the overall operational efficiency of the managed server S. The processor 100 converts the native color values into 6-bit color values and stores the video graphics block 200 in the 6-bit color pixel block 208 located in local RAM memory 108 . At a step 302 , the processor 100 hashes the 6-bit color pixel block 208 to generate a unique number or hashing code. The 16-bit hashing algorithm 204 is preferred since it runs faster than a 32-bit hashing algorithm, but a 32-bit hashing algorithm may be used to increase accuracy.
If processing the first screen of data (i.e. first pass), the process branches at step 304 to step 306 where the hash code is stored in the hash code table 202 . Next, if processing the first pixel block 200 of a row that has changed, the process branches from step 308 to step 310 where the pixel block 200 is compressed using the compression algorithm 210 , explained more fully with reference to FIG. 9 . If not processing the first changed pixel block 200 of a row, the process branches from step 308 to step 311 where the process again branches to step 308 if the previously positioned block did not change. For example, if a block was skipped after one or more changed blocks. Otherwise, if the previously positioned block did change, the process branches to step 312 where the hash code corresponding to the current block is compared to the previous block. For example, if processing pixel block (0,1), the hash code of pixel block (0,1) is compared to the hash code of pixel block (0,0) stored in the hash code table 202 .
If the hash codes are equal, processing branches from step 314 to step 316 . If processing the first screen of data, the process branches at step 316 to step 318 where a second more detailed comparison is performed. This more detailed comparison is performed to assure that the pixel blocks are indeed equal. It is especially important on this first pass to assure that good data is transmitted. Alternatively, a more accurate hashing code, such as a 32-bit algorithm, could be utilized to avoid this second check. If the bytes of both pixel blocks match, then processing continues from step 320 to step 322 where the byte compression pipeline is flushed to move any previously accumulated “byte repeats” into the transmit buffer 212 . At step 324 , the repeated block count 216 is incremented to start a count of repeated blocks.
Referring back to step 314 , if the hash codes are not equal, processing branches from step 314 to step 326 where the block compression pipeline is flushed to move any previously accumulated “block repeats” into the transmit buffer 212 . Next, the new pixel block 200 is compressed using the compression algorithm 210 .
Referring back to step 304 , if not processing the first screen of data (i.e. first pass), the process branches from step 304 to step 328 where the hash code generated for the current block is compared to the hash code value stored in the hash code table 202 corresponding to the current block location. If the hash codes are not equal, the process branches from step 330 to step 306 (discussed above). If the hash codes are equal, the process branches from step 330 to step 332 where the block is skipped, meaning that the video graphics data has not changed for this pixel block 200 . Next, the compression pipeline is flushed to move any previously accumulated “block repeats” into the transmit buffer 212 and to assure that the byte repeat counter is cleared.
Now referring to FIG. 7C , processing continues from steps 324 , 310 or 334 to step 336 to check for an end of row condition. If not at the row end, processing branches from step 336 to step 338 where the process moves to the next block and continues at step 300 . If at the row end, processing branches from step 336 to step 340 to flush the compression pipeline including the byte and block repeat counters. Next, processing continues at step 342 where the transmit buffer is developed into a transmit packet and transmitted to the remove console C via the modem 112 a or NIC 110 . Next, mouse and video configuration changes are identified. If no changes are detected, processing branches from step 346 to step 338 . If changes are detected, processing branches from step 346 to step 348 to determine if a text mode has been entered. If so, processing terminates. If not so, processing branches from step 348 to step 350 where the mouse and/or video configuration changes are transmitted to the remote console C and processing returns to step 338 to process another row. Although the mouse and video configuration changes are transmitted in a separate packet from the data, it is understood that they could be transmitted in a combined packet.
Now turning to FIGS. 8A-C , there is illustrated three variations of flushing the compression pipeline. FIG. 8A illustrates a general flush routine. At a step 400 , the process branches to step 402 if the block repeat count 216 is greater than zero. At step 402 , a repeat block command is formed and written to the transmit buffer 212 . Next at step 404 , the repeat block count is cleared to ‘0’ in preparation for the next repeated block.
If at step 400 , the block repeat count 216 is zero the process branches to step 406 . At step 406 , the process branches to step 408 if the byte repeat count is greater than four. At step 408 , a repeat byte command is formed based on the repeated byte in the repeated data buffer 220 and the repeat byte count 218 . The repeat byte command is written to the transmit buffer 212 . For example, if the repeated byte count is 5 for a data byte 0x45, the value 0x45ffe605h would be written to the transmit buffer 212 to communicate that a string of six bytes were compressed. If, at step 406 , the byte repeat count is less than or equal to four the process branches to step 410 where the repeated byte in the repeated data buffer 220 is written to the transmit buffer 212 according to the count. If the count is zero nothing is written. Unless the byte count is greater than four, it is a more efficient use of resources to simply replicate the repeated byte the number of times indicated by the repeated byte count 218 . For example, if the repeated byte count is three for the data byte 0x45, the value 0x45454545h would be written to the transmit buffer 212 to communicate the four bytes.
After steps 408 or 410 , the repeated byte count is cleared to ‘0’ in step 412 in preparation for the next repeated byte.
FIG. 8B illustrates a flush byte compression pipeline routine. At step 420 , the process branches to step 422 if the byte repeat count is greater than four. At step 422 , a repeat byte command is formed based on the repeated byte in the repeated data buffer 220 and the repeat byte count 218 . The repeat byte command is written to the transmit buffer 212 . If, at step 420 , the byte repeat count is less than or equal to four the process branches to step 424 where the repeated byte in the repeated data buffer 220 is written to the transmit buffer 212 according to the count. If the count is zero nothing is written. After steps 422 or 424 , the repeated byte count is cleared to ‘0’ in step 426 in preparation for the next repeated byte.
FIG. 8C illustrated a flush block compression pipeline routine. At a step 430 , the process branches terminates and returns to the calling routine if the block count is equal to zero. Otherwise, the process continues to step 432 , where a repeat block command is formed and written to the transmit buffer 212 . Next at step 434 , the repeat block count is cleared.
Now turning to FIG. 9 , there is illustrated the compress block routine called in step 310 . At a step 450 , if the repeated data buffer 220 is empty, the process branches to step 452 to read the first data byte and write it to the repeated data buffer 220 . Otherwise, the process branches to step 454 to read the next data byte. Next, at step 456 , the next data byte is compared to the data byte in the repeated data buffer 220 . If the bytes are not equal, the process branches from step 458 to step 460 where the flush byte compression pipeline is called. After returning from the flush byte compression pipeline routine, at step 462 the next data byte (read at step 454 ) is written to the repeated data buffer 220 .
If at step 458 , the bytes are equal, the process branches from step 458 to step 464 where the repeat byte count 218 is incremented. From steps 462 and 464 , the process loops back to step 450 if not at the end of the 6-bit color pixel block 208 . If at the end of a block, the routine returns to the calling process.
Referring now to FIGS. 10A-C , there is illustrated the methods related to reading, analyzing, compressing and transmitting video graphics data to the remote console C according to the preferred embodiment of the present invention. Generally, the process is similar that described in FIGS. 7A-B , except that instead of reading every pixel block 200 sequentially, the screen is sampled for changing data based on a pattern or count. For example, every second, third, fourth (as indicated by ‘X’), etc., pixel block 200 can be read as illustrated in FIG. 11A . The sampling rotates every pass of the screen so that every pixel block 200 is eventually read. For example, if sampling every fourth pixel block, it would take four passes of the screen to read every pixel block of the screen.
Once a changed pixel block 200 is located, the surrounding pixel blocks 200 may be marked for accelerated checking based on the likelihood that the surrounding pixel blocks 200 would also change. One example of marking surrounding pixels blocks is illustrated in FIG. 11B . A changed pixel block 200 was located at row 4 , column 4 . The surrounding pixel blocks are marked (as indicated by ‘M’) in a proximity table 222 so that they will be checked next rather than wait for the next sampling. This results in changed data being passed to the remote console C faster than the method described in FIGS. 7A-B . It is noted that the marked pixel block above and left of the current block will not be read until the next pass.
At a step 500 , the process branches to step 502 if processing the first screen of data (i.e. first pass). At step 502 , a pixel block 200 is read and converted to 6-bit color. Next, at step 504 , the process hashes the 6-bit color pixel block 208 to generated a unique number or hashing code.
If not processing the first screen of data, the process branches at step 500 to step 506 . At step 506 , the process branches to step 508 if the pixel block 200 is not marked in the proximity table 222 for accelerated reading. At step 508 , the process branches to step 510 to move to the next pixel block 200 if the pixel block 200 is not designated for reading on this pass.
Designating pixel blocks 200 for sampling can be accomplished with row and column modulo counters. For example, if every fourth block is to sampled, on a first pass every ‘0’ block will be read according to the column modulo-4 counter. On the second pass every ‘1’ block will be read. A second modulo-4 counter can control the offset according to the row. FIG. 11A illustrates the resulting pattern. Other patterns can be designed according to the types of images that are displayed. For example, instead of reading rows from top to bottom, a diagonal or circular scheme could be developed.
Thus, if the pixel block 200 is not a surrounding “marked” block or a block designated for sampling, the process branches from step 508 to step 510 to move to the next block. Otherwise, the process branches to step 512 from steps 506 and 508 to read the pixel block 200 and convert to 6-bit color. Next, at step 514 , the process hashes the 6-bit color pixel block 208 to generated a unique number or hashing code. When a block is hashed, its corresponding bit in the proximity table 222 is cleared. At step 516 the hash code generated for the current block is compared to the hash code value stored in the hash code table 202 corresponding to the current block location. If the hash codes are equal, the process branches from step 518 to step 520 where the block is skipped and the block is unmarked, meaning that the video graphics data has not changed for this pixel block 200 . Next at step 522 , the compression pipeline is flushed to move any previously accumulated “block repeats” into the transmit buffer 212 and assure that the repeated byte count is cleared.
If at step 518 the hash codes are not equal, the process branches from step 518 to step 524 to mark the current block and surrounding blocks as illustrated in FIG. 11B .
The process continues from steps 524 and 504 to step 526 where the calculated hash code is stored in the hash code table 202 . Next, if processing the first pixel block 200 of a row that has changed, the process branches from step 528 to step 530 where the pixel block 200 is compressed using the compression algorithm 210 , explained more fully with reference to FIG. 9 . If not processing the first changed pixel block 200 of a row, the process branches from step 528 to step 531 where the process again branches to step 530 if the previously positioned block did not change. For example, if a block was skipped after one or more changed blocks were processed. Otherwise, if the previously positioned block did change, the process branches to step 532 where the hash code corresponding to the current block is compared to the previously positioned block. For example, if processing pixel block (0,1), the hash code of pixel block (0,1) is compared to the hash code of pixel block (0,0) stored in the hash code table 202 .
If the hash codes are equal, processing branches from step 534 to step 536 . If processing the first screen of data, the process branches at step 536 to step 538 where a second more detailed comparison is performed. This more detailed comparison is performed to assure that the pixel blocks are indeed equal. It is especially important on this first pass to assure that good data is transmitted. Alternatively, a more accurate hashing code, such as a 32-bit algorithm, could be utilized to avoid this second check. If the bytes of both pixel blocks match, then processing continues from step 540 to step 542 where the byte compression pipeline is flushed to move any previously accumulated “byte repeats” into the transmit buffer 212 . At step 544 , the repeated block count 216 is incremented to start a count of repeated blocks.
Referring back to step 534 , if the hash codes are not equal, processing branches from step 534 to step 546 where the block compression pipeline is flushed to move any previously accumulated “block repeats” into the transmit buffer 212 . Next, the new pixel block 200 is compressed using the compression algorithm 210 .
Now referring to FIG. 10C , processing continues from steps 544 , 530 or 522 to step 548 to check for an end of row condition. If not at the row end, processing branches from step 548 to step 510 where the process moves to the next block and continues at step 500 . If at the row end, processing branches from step 548 to step 550 to clear the marked pixel blocks on the current row. Additionally, the second “column” modulo is decremented to offset the next row of sampled pixel blocks by one block as illustrated in FIG. 11A . Next, processing continues to step 552 where the repeated byte and block data is flushed into the transmit buffer 212 . Next, processing continues at step 554 where the transmit buffer is developed into a transmit packet and transmitted to the remove console C via the modem 112 a or NIC 110 . Next, mouse and video configuration changes are identified. If no changes are detected, processing branches from step 558 to step 548 . If changes are detected, processing branches from step 558 to step 560 to determine if a text mode has been entered. If so, processing terminates. If not so, processing branches from step 560 to step 562 where the mouse and/or video configuration changes are transmitted to the remote console C.
Thus, there has been described and illustrated herein, a method and apparatus for reading, analyzing, compressing and transmitting video graphics data to a remote console C. However, those skilled in the art should recognize that many modifications and variations in the size, shape, materials, components, circuit elements, wiring connections and contacts besides those specifically mentioned may be made in the techniques described herein without departing substantially from the concept of the present invention. Accordingly, it should be clearly understood that the form of the invention described herein is exemplary only and is not intended as a limitation on the scope of the invention. | A method and apparatus for updating video graphics changes of a managed server to a remote console independent of an operating system. The screen (e.g. frame buffer) of the managed server is divided into a number of blocks. Each block is periodically monitored for changes by calculating a hash code and storing the code in a hash code table. When the hash code changes, the block is transmitted to the remote console. Color condensing may be performed on the color values of the block before the hash codes are calculated and before transmission. Compression is performed on each block and across blocks to reduce bandwidth requirements on transmission. Periodically, the configuration of a video graphics controller and a pointing device of the managed server are checked for changes, such as changes to resolution, color depth and mouse movement. If changes are found, the changes are transmitted to the remote console. The method and apparatus may be performed by a separate processor as part of a remote management board, a “virtual” processor by causing the processor of the managed server to enter a system management mode, or a combination of the two. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a fallable type pole supporting device suitable for mounting a fallable pole having a position confirming flag on an upper end thereof, such as used when traveling forests, wasteland, etc. in an off-road vehicle, or for mounting a pole-like member such as an antenna.
2. Description of Relevant Art
A confirming flag for a vehicle, in which a pole having a flag at an upper portion thereof is mounted at its lower portion on a vehicle body, has been heretofore known.
As disclosed in Japanese Utility Model Application Laid-Open Publication No. 52-7600, a known confirming flag of this kind comprises a pole, a piece of flag-cloth attached to an upper portion of the pole, and fittings for the vehicle body mounted to a lower portion of the pole.
In the aforesaid publication, in the event the pole engages an obstacle, a shock is absorbed by elastic deformation of the pole, and therefore, a great force acts on the fittings at the lower portion of the pole. Thus, it was necessary to provide a sufficient rigidity of the mounting fittings to withstand such great force. In this regard, however, there was an inconvenience that when the pole is once disengaged from the mounting fittings, a connecting state relative to the vehicle body disappears, and as a result, the pole will be lose during traveling.
SUMMARY OF THE INVENTION
The present invention has been accomplished in order to solve the aforesaid problems.
It is an object of the present invention to provide a fallable type pole supporting device for a vehicle which can be elastically deformed without exerting a great force on a mounting portion of the vehicle body even if a pole supported by the device engages an obstacle during traveling.
Another object of the invention is to provide such a device which prevents the pole from becoming fully disengaged from the vehicle body.
For achieving the aforesaid objects, the device of the present invention is characterized in that a wire extending in a longitudinal direction of a pole is fixed to a mounting side end of a pole member, a resilient member is disposed between an extreme end of said wire and said mounting side end of the pole member, said pole member and the longitudinal direction of the wire are normally maintained in a straight line by a resilient force in an axial direction of said resilient member, the mounting side end of said pole member is tiltably supported by the resilient member, and said pole member is secured to a base body through said wire.
With the arrangement as described above, when the pole as mounted on an off road vehicle engages an obstacle, the pole is flexed and tilted. In this state, the longitudinal direction of the wire is deviated from the longitudinal direction of the pole member. Therefore, in order to absorb such deviation and restore it to a straight line with the pole, the wire is pulled back by the resilient force in an axial direction of the resilient member, and the pole member is again stood upright from its tilted state.
Moreover, since the pole member is secured to the vehicle body by the wire, even if the pole member is significantly tilted, such as in a vehicle rollover, the pole member will not be disengaged from the vehicle body.
Other objects, advantages and salient features of the present invention will be understood from the following detailed description which, when taken into conjunction with the annexed drawings, discloses preferred embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view showing one preferred embodiment of a fallable pole supporting device according to the present invention.
FIG. 2 is a sectional view similar to FIG. 1, but showing a state where the pole of FIG. 1 is tilted.
FIG. 3 is a sectional view showing a further preferred embodiment of a fallable type pole supporting device according to the present invention.
FIG. 4 is a perspective view showing a fallable type pole supporting device according to FIGS. 1 or 3 mounted on a buggy type off road vehicle.
FIGS. 5 and 6 are respective explanatory views showing another preferred embodiment of a fallable type pole supporting device according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Embodiments of the present invention will be described in detail with reference to the drawings.
Referring to FIGS. 1 and 2, the reference numerals designate the following: 1 a fallable type flag pole; 2, 3 upper and lower spring seats, respectively; 4 a return spring; 5 a mounting plate mounted on the upper spring seat 2; 6 an annular pedestal provided on the mounting plate 5; 7 a tilting member tiltably provided on the pedestal 6; 8 a flexible pole provided on the tilting member 7; 9 a wire or cable mounted integrally with the pole 8; 10 a fixed element secured to one end of the wire 9; 11 a washer; and 12 a rubber boot having one end adhered to the mounting plate 5 surrounding the tilting member 7.
Each of the upper and lower spring seats 2 and 3 is in the form of a plate. The lower spring seat 3 is provided in its central portion with a hole 3a into which the washer 11 is fitted, and the upper spring seat 2 is provided in its central portion with a hole 2a through which the wire 9 extends.
One end of the mounting plate 5 is mounted on a part of a frame of the vehicle, and the other end of the mounting plate 5 is formed with a hole 5a through which the wire 9 also extends. The mounting plate is also formed with a plurality of small holes (one of which is shown at 5b) in which projections on the bottom surface of the pedestal 6 are fitted, and with a plurality of small recesses (one of which is shown at 5c) in which projections on the bottom surface of the rubber boot 12 are fitted.
The pedestal 6 is constructed in the form of a seat in which the upper surface allows the tilting member 7 to be seated, while the plurality of projections on the bottom surface of the pedestal are fitted in and mounted to the plurality of the small holes 5b in the mounting plate 5.
The tilting member 7 has a convex portion 7a tiltably fitted in the upper surface of the pedestal 6, and a concave portion 7b which cooperates with a convex portion 6a of the pedestal 6 for facilitating tilting movement of a tilting member. Also, one end of the pole 8 and one end of the wire 9 mounted integrally with the pole 8 are provided in an opening defined along the center line of the tilting member 7. The pole 8 is preferably formed of resin, but can be formed of metal or other appropriate materials. One end of the wire 9 is integrally molded at the lower end of the pole 8, and a flag is detachably mounted on the upper end of the pole 8.
In assembling the fallable flag pole 1, the return spring 4 is provided between the upper and lower spring seats 2 and 3, the tilting member 7 is placed on the pedestal 6, and the extreme end of the wire 9 is projected downwardly out of the hole 3a of the lower spring seat 3. In this state, the washer 11 is passed through the extreme end of the wire, the spring 4 is compressed to an extent and the fixed element 10 is fixed to the extreme end of the wire.
As thus assembled, the pole 8 is maintained straight since the wire 9 is strongly pulled by the resilient force of the return spring 4.
When the pole 8 engages an obstacle during traveling (with the mounting plate 5 mounted on the vehicle) the pole 8 is flexed and tilted as shown in FIG. 2, the upper surface of the pedestal 6 is pressed by the tilting member 7 which tilts with the pole 8, and the wire 9 is pulled thereby further compressing the spring 4. Therefore, a distance between the upper and lower spring seats 2 and 3 is narrowed against the resilient force of the return spring 4. Then, when the pole passes out of engagement with the obstacle, the wire 9 is pulled back by the resilient force of the return spring 4, the convex portion 7a of the tilting member 7 is fitted back into the seating surface of the pedestal 6 and the pole 8 is again stood upright.
FIG. 3 shows a second embodiment, in which reference numeral 31 designates a fallable flag pole, and 4, 7, 8, 10 and 11 are elements similar to those of the first embodiment. Additional reference numerals designate the following: 32 and 33 upper and lower springs seats, respectively; 34 a wire, 35 a rubber boot, 36 a stopper shaft welded to the spring seat 32; 37 a flat washer, 38 a bolt, 39 fittings, 40 a bolt, and 41 a nut.
The upper spring seat 32 is provided with a hole 32a through which the wire 34 extends. An upper peripheral edge of spring seat 32 defining the hole 32a projects upwardly to define a seat surface 32b. The convex portion 7a of the tilting member 7 is fitted in the hole 32a and the seat surface 32b so that the former may be tiltably seated. One end of an arm 32c formed integrally with the upper spring seat 32 is provided with a mounting hole through which the bolt 40 passes. One end of the stopper shaft 36 is welded to the lower surface of the upper seat 32 in the vicinity of the hole 32a, and the other end of the shaft 36 is bored with a female thread 36a meshed with the bolt 38.
The lower spring seat 33 is in the form of a plate. The lower spring seat 33 is provided in its central portion with a hole 33a into which the washer 11 is fitted and a hole 33b for guiding the stopper shaft 36 is provided in the vicinity of the hole 33a.
In assembling the fallable type flag pole 31, the return spring 4 is provided between the upper and lower spring seats 32 and 33, the tilting member 7 is provided on the upper spring seat 32, the spring 4 is compressed to an extent, and the extreme end of the wire 34 is projected out of the hole 33a of the lower spring seat 33. In this state, the extreme end of the wire 34 passes through the washer 11, and the fixed element 10 is fixed to the wire and fitted in the guide hole 33a of the lower spring seat 33, and the bolt 38 is meshed with the threaded portion 36a through the flat washer 37.
As thus assembled, the pole 8 is maintained straight since the wire 34 is strongly pulled by the resilient force of the return spring 4.
In the fallable flag pole 31 for the vehicle, one end of the arm 32c formed integrally with the upper spring seat 32 is mounted on one end of the fittings 39 by means of bolt 40 and nut 41, while an opposite end of the fittings is welded or otherwise fixed to the frame of the vehicle. When the pole 8 engages an obstacle during the travel of the vehicle, the pole 8 is flexed and tilted, the convex portion 7a of the tilting member 7 presses the seat surface 32b of the upper spring seat 32, the wire 34 is pulled, and the distance between the upper and lower spring seats 32 and 33 is narrowed against the resilient force of the return spring 4. At this time, the lower spring seat 33 is guided by the stopper shaft 36. After the pole 8 is out of engagement with the obstacle, the wire 34 is pulled back by the resilient force of the return spring 4, the convex portion 7a of the tilting member 7 is fitted into the hole 32a of the upper spring seat 32, and the pole 8 is again stood upright.
In this embodiment, even if the wire 34 is broken or severed when the pole 8 is largely tilted, the lower spring seat 33 will be held by the plate washer 37 and bolt 38 provided on the stopper shaft 36. Accordingly, if the wire 34 is severed all components of the flag pole and supporting device will remain attached to the vehicle.
In the fallable flag pole, as shown in FIG. 4, one end of the arm 32c of the upper spring seat 32 (or of a mounting plate such as shown at 5 in FIG. 1) is mounted on the fittings 39 welded to the frame of the vehicle. During travel of the vehicle, the pole 8 is normally stood upright by the supporting device, and when the vehicle is moved into a garage the pole 8 may be bent against the resiliency of the spring 4 and maintained in such bent position by a mirror 41 or a catch device provided for such purpose. As shown in FIG. 4, the pole supporting device is mounted on the off-road vehicle at a higher level than the mirror or catch device, so that when the pole 8 is in the bent position it extends downwardly toward the mirror.
FIGS. 5 and 6 are respectively explanatory views showing another embodiment of a fallable type pole supporting device according to the present invention. In the drawings, reference numeral 51 designates a fallable type flag pole; 52 a tilting member provided on the pole 51; 53 a pedestal; 54 a plate spring; 55 a connecting rod; 56, 56 stoppers for the plate spring 54 secured to opposite ends of the connecting rod 55; 57 a stopper on the reset side for the plate spring 54 secured onto the connecting rod 55; and 58 mounting bed.
The plate spring 54 may be selectively invertedly formed into a concave shape or a convex shape in its central portion by applying an appropriate load to opposite sides thereof. The plate spring is sandwiched between the pedestal 53 and the mounting bed 58 at the peripheral edge thereof using the bolt and nut fasteners as shown, while fittings 39 have one end secured to the mounting bed 58 by the same fasteners, and an unshown end of the fittings 39 would be secured to the vehicle.
The connecting rod 55 connects the tilting member 52 and the flat spring 54 by the stoppers 56, 56.
In the state where the fallable flag pole 51 is stood upright, as shown in FIG. 5, the flat spring 54 is in the state where a concave portion is formed. The tilting member 52 is pulled downward by the connecting rod 55 and which is in turn urged downwardly by a pulling force of the spring 54 so that the tilting member is securely fitted into the concave portion of the pedestal 53 and the force of the spring prevents the tilting member from wobbling.
Where the pole 8 impinges upon an obstacle, the fallable flag pole 51 and the tilting member 52 are pulled out of the concave portion of the pedestal 58 due to the principle of lever and pivots freely on the stopper 56 together with the pole 8, as shown in FIG. 6. At this time, the plate spring 54 is pulled upward by the connecting rod 55 and changes from the state where a concave portion is formed to the state where a convex portion is formed.
It is contemplated that when a tilted pole 8 is automatically stood upright again by the force of the return spring 4 as described above in relation to FIGS. 1-4, the pole 8 may hit the vehicle frame. However, the fallable type flag pole 51 shown in the third embodiment does not automatically return to an upright position, and can be suitably reset by a rider from the state shown in FIG. 6 to the state shown in FIG. 5 by pushing the tilting member 52 down into the concave portion of the pedestal 53.
According to desirable aspects of the present invention, the presently preferred embodiments of which are described above, even if the pole member mounted on the vehicle engages an obstacle, the pole supporting device prevents a great force from acting on the mounting side of the vehicle body because the supporting device itself is elastically deformable, thereby minimizing stress of the pole and improving durability of the pole. Furthermore, since the pole member is fastened to the vehicle body by the wire member or the connecting rod, the pole member is prevented from being lost.
The supporting device of the present invention is able to achieve the above advantages not only with respect to the flag pole as described above, but also with respect to any rod member, such as an antenna.
Although there has been described what are at present considered to be the preferred embodiments of the present invention, it will be understood that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all aspects as illustrative, and not restrictive. The scope of the invention is indicated by the appended claims rather than the foregoing description. | The present invention discloses a fallable type pole supporting device comprising a wire extending in a longitudinal direction of a pole extended to a mounting side end of a pole member. A resilient member is disposed between an extreme end of the wire and a mounting side end of the pole member. The pole member and the longitudinal direction of the wire are maintained in a straight line by a resilient force in an axial direction of the resilient member. A lower mounting end of the pole member is tiltably maintained and the pole member is made engageable with a base body through said wire. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a motor drive circuit for a radio-controlled model, and more particularly to a motor drive circuit used for driving a motor of a model unit such as, for example, a model electric car.
A pulse stretcher circuit common to a servo IC which has been conventionally used for a motor controller amplifier is disclosed in Japanese Patent Publication No. 48352/1986 and constructed in such a manner as shown in FIG. 4.
More particularly, the conventional pulse stretcher circuit includes a first transistor 20 of which the emitter is grounded and a second transistor 21 of which the base is connected to the collector of the first transistor 20 and the emitter is grounded. A connection P between the collector of the first transistor 20 and the base of the second transistor 21 is grounded through a resistor R1 and a capacitor C1, and between the connection P and a power supply is connected a current source 22. Also, the pulse stretcher circuit includes a resistor connected between the collector of the second transistor 21 and the power supply.
In the pulse stretcher circuit constructed as described above, when a difference signal indicating the difference between a pulse signal fed from a receiver and a one-shot pulse formed within a motor controller is input to the first transistor 20, it stretches the difference signal over a period of time sufficient to cause a motor of a controlled mode to be actually driven, to thereby generate an output signal. More specifically, the variation of either the resistor R1 or the capacitor C1 permits the relationship between the difference signal and the output signal to be varied, so that the signal extended by the pulse stretcher circuit is subject to power amplification to drive the motor.
The pulse stretcher circuit described above employs the charge discharge characteristics of the capacitor to stretch the difference signal. Thus, the circuit permits the whole inclination of the input-output characteristics expressed when the pulse width of the difference signal is indicated on an X axis and the pulse width of the difference signal after it has been stretched is indicated on a Y axis to be freely varied. However, it fails to vary only the portion of the inclination within any specific range. For example, it fails to permit the pulse width of the difference signal to render only the portion of the inclination within a specific region steep or gentle.
This causes a manipulator to fail to sufficiently maintain a control region extending between an intermediate speed and a maximum speed which is most required during the controlling of a model electric car or the like, so that the conventional pulse stretcher circuit fails to exhibit satisfactory controllability when delicate controlling is required as in a race or the like.
SUMMARY OF THE INVENTION
The present invention has been made in view of the foregoing disadvantage of the prior art.
Accordingly, it is an object of the present invention to provide a motor drive circuit for a radio-controlled model which is capable of partially varying the inclination of the input-output characteristics as desired to facilitate the controlling of a model unit in a rotation region most required.
It is another object of the present invention to provide a motor drive circuit for a radio-controlled model which is capable of accomplishing the above-described object while significantly decreasing the manufacturing costs.
It is a further object of the present invention to provide a motor drive circuit for a radio-controlled model which is capable of accomplishing the above-described objects with a highly simplified circuit arrangement and without requiring a transmitter provided with any specific function.
In accordance with the present invention, there is provided a motor drive circuit for a radio-controlled model comprising a means for converting a signal corresponding to a control condition into a digital signal and subjecting the digital signal to weighing processing for every bit thereof to optionally vary the inclination of the input-output characteristics.
In the present invention constructed as described above, when a manipulator controls a transmitter, a signal generated from the transmitter in correspondence to the control condition is received by a receiver. The received signal is then converted into a digital signal and thereafter subject to weighing processing, resulting in any desired portion of the input-output characteristics being optionally varied as desired.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings; wherein:
FIG. 1 is a block diagram generally showing a model controlling device to which an embodiment of a motor drive circuit for a radio-controlled model according to the present invention may be applied;
FIG. 2 is a block diagram showing a pulse width conversion circuit;
FIG. 3 is a block diagram showing a circuit of a D/A converter; and
FIG. 4 is a circuit diagram showing a conventional pulse stretcher circuit common to a servo IC used for a motor controller amplifier.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Now, a motor drive circuit for a radio-controlled model according to the present invention will be described hereinafter with reference to FIGS. 1 to 3, wherein like reference numerals designate like or corresponding parts throughout.
FIG. 1 illustrates a model controlling device to which an embodiment of a motor drive circuit for a radio-controlled model according to the present invention may be applied. A motor drive circuit of the illustrated embodiment is adapted to control the drive of a motor of a model controlling device for controlling a model unit such as, for example, a model electric car or the like.
A model controlling device to which the embodiment is applied includes a transmitter 1, a receiver 2, a steering servo 3 and a motor controller 4. The motor controller 4 includes an internal one-shot circuit 5, a pulse width comparison circuit 6, a pulse width conversion circuit 7 and a power amplification circuit 8.
The transmitter 1 is adapted to generate a pulse train signal of a predetermined wavelength depending upon the operation of a stick by a manipulator, to thereby control a controlled unit in a desired direction.
The receiver 2 includes a wave detection circuit and a decoder and is so constructed that the wave detection circuit detects a signal fed from the transmitter 1 to demodulate various control signals of, for example, about 50 Hz and the decoder divides the control signals into signals for channels, that is, a signal for controlling a motor and that for operating a handle to feed the handle operating signal to the steering servo 3 and feed the motor controlling signal to the pulse width comparison circuit 6, resulting in being transmitted as pulse width information for every cycle of, for example, 14 to 22 msec.
The steering servo 3 produces a drive signal for operating the handle from various control signals fed from the receiver 2. The drive signal acts to control the inclination of the wheels of a controlled unit to a predetermined angle to control the direction of advance of the controlled unit such as right-turn, left-turn or the like.
The internal one-shot circuit 5 serves to feed a reference pulse set therein to the pulse width comparison circuit 6.
The pulse width comparison circuit 6 is adapted to compare a signal of about 50 Hz input thereto from the receiver 2 with the reference pulse produced in synchronism with the input signal and fed from the internal one-shot circuit 5 to prepare the difference therebetween, so that a signal corresponding to forward movement or rearward movement based on, for example, the trailing of the reference pulse may be output as a difference signal to the pulse width conversion circuit 7.
The pulse width conversion circuit 7 functions to convert a variation of the difference signal varied depending upon the width of a pulse input thereto from the pulse width comparison circuit 6. For this purpose,, the pulse width conversion circuit 7, as shown in FIG. 2, includes a pulse width/DC conversion circuit 9, an A/D conversion circuit 10, a D/A converter 11, a triangular wave oscillation circuit 12, and a comparison circuit 13.
The pulse width/DC conversion circuit 9 converts the pulse width (time) of the difference signal fed from the pulse width comparison circuit 6 into a DC voltage signal corresponding thereto to feed it to the A/D conversion circuit 10.
The A/D conversion circuit 10 acts to convert the DC voltage signal of an analog form fed from the pulse width/DC conversion circuit 9 into a digital signal of, for example, sixteen stages to deliver it to the D/A converter 11.
The D/A converter 11 includes a weighing circuit 11a and a current/voltage conversion circuit 11b. The weighing circuit 11a, as shown in FIG. 3, includes latch circuits 11aa and weighing resistors 11ab corresponding in number to the number of bits of a signal generated from the pulse width/DC conversion circuit 9. The so-constructed weighing circuit 11a is adapted to latch the digital signal of sixteen stages fed from the A/D conversion circuit 10 by means of the latch circuits 11aa, respectively, to thereby cause a variation of the difference signal varied out weighing processing of the digital signal for every bit of the digital signal.
The resistance of each of the weighing resistors 11ab is set so as to have a predetermined value depending upon a curve of input-output characteristics desired and currents flowing through the weighing resistors 11ab are added to each other and then fed to a non-invention input terminal of a differential-type amplifier constituting the current/voltage conversion circuit 11b.
The current/voltage conversion circuit 11b converts a value of a current fed from the weighing circuit 11a into a voltage value, which is then fed to a non-inversion input terminal of a comparator constituting the comparison circuit 13.
The triangular wave oscillation circuit 12 acts to produce a triangular wave of a predetermined frequency (for example, 5 kHz) depending upon an oscillation signal fed from an oscillator and feeds it to the non-inversion input terminal of the comparison circuit 13, which then compares a voltage signal fed from the current/voltage conversion circuit 11b with a voltage of the triangular wave fed from the triangular wave oscillation circuit 12 to feed, to the power amplification circuit 8, a signal of a pulse width corresponding to the output of the triangular wave obtained over a period of time during which the voltage signal from the current/voltage conversion circuit 11b is high as compared with the voltage of the triangular wave. The input signal from the receiver 2, as described above, has a frequency of about 50 Hz and the triangular wave has a frequency of about 5 kHz, resulting in the signal input to the power amplification circuit 8 having a high frequency of about 5 kHz. This permits a number of pulses to be used for drive the motor even when the difference signal has a small pulse width, so that fine driving may be accomplished while withstanding an inertia force of the motor.
The power amplification circuit 8 serves to amplify the signal fed from the comparison circuit 13 and feed a drive current to a DC motor 14 in order to ensure desired controlling of a model unit depending upon the output of the transmitter 1.
Now, the manner of operation of the motor drive circuit of the illustrated embodiment constructed as described above will be described hereinafter.
When a manipulator operates a stick of the transmitter 1, signals of a predetermined wavelength corresponding to the operation of the stick are output from the transmitter 1. The so-output signals are then received by the receiver 2, which divides the signals into a signal for controlling the motor and that for operating the handle. The handle operating signal is fed to the steering servo 3, which then moves wheels of a controlled unit to a predetermined angle depending upon the signal fed thereto.
The motor controlling signal is fed to the pulse width comparison circuit 6, which compares it with a reference signal fed from the internal one-shot circuit 5 to feed a difference signal corresponding to the forward movement or rearward movement of the controlled unit to the pulse width conversion circuit 7. The conversion circuit 7 converts the difference signal into a DC voltage corresponding to the pulse width of the difference signal and then converts it into a digital signal of sixteen stages, which is then fed to the D/A converter 11. The D/A converter 11 subjects the digital signal of sixteen stages to weighing processing for every bit of the digital signal by means of the weighing resistors 11ab, so that currents flowing through the weighing resistors 11ab are added together and then fed to the comparison circuit 13. The comparison circuit 13 carries out the comparison between a voltage signal from the current/voltage conversion circuit 11b and a triangular wave from the triangular wave oscillation circuit 12 to feed a signal of a pulse width corresponding to the output of the triangular wave obtained for a period of time during which the voltage signal is kept high as compared with the triangular wave to the power amplification circuit 8. The power amplification circuit 8 provides the DC motor 14 with a drive current depending upon the signal fed from the comparison circuit 13, so that the controlled or model unit may be controlled corresponding to the output of the transmitter.
Thus, in the illustrated embodiment, the pulse width conversion circuit 7 subjects the difference signal based on the digital signal corresponding to the output from the transmitter and subjected to A/D conversion to the weighing processing for every bit of the digital signal to carry out fine adjustment of the value of the current flowing through each of the weighing resistors 11ab, so that the currents flowing therethrough are added together and then converted to the voltage signal again. Then, the voltage signal is compared with the triangular wave to generate the PWM signal, to thereby control the driving of the DC motor 14. Thus, the inclination of the input-output characteristics can be optionally varied as desired by setting the resistance of each of the weighing resistors 11aa in correspondence to the input-output characteristics required. This results in the control region for controlling a model unit being sufficiently maintained, to thereby facilitate controlling of the model unit in a rotation region which is required most. Also, this permits the motor drive circuit of the illustrated embodiment to be free from a function of a conventional transmitter of high quality of carrying out pseudo-control of a motor by means of an exponential curve, so that the motor control device may effectively control a motor even when an inexpensive transmitter is used.
In the illustrated embodiment, the conversion of a signal converted into a DC voltage into a digital signal has been illustratively described in connection with the digital signal of sixteen stages. However, the number of stages of the digital signal may be varied depending upon the performance of a controlled unit, therefore, the digital signal is not limited to any specific number of stages. Also, the above description has been made in connection with the weighing resistors 11aa each having a resistance previously fixedly set in correspondence with the input-output characteristics. However, the weighing resistors each may comprise a variable resistor, which may be variably controlled depending upon the input-output characteristics.
As can be seen from the foregoing, the motor drive circuit of the present invention can vary any desired part of inclination of the input-output characteristics with a highly simplified circuit arrangement and without requiring a transmitter with any specific function as in the prior art, to thereby facilitate motor control in a rotation region most required when a model unit is controlled.
While a preferred embodiment of the invention has been described with a certain degree of particularity with reference to the drawings, obvious modifications and variations are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. | A motor drive circuit for a radio-controlled model capable of readily varying any desired part of inclination of the input-output characteristics with a highly simplified circuit arrangement. The motor drive circuit includes an element for converting a signal corresponding to control condition into a digital signal and subjecting the digital signal to weighing processing for every bit thereof. | 0 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The present application is a continuation of co-pending U.S. patent application Ser. No. 13/205,115, to Graves et al., entitled “OPTICAL SWITCH WITH POWER EQUALIZATION,” filed Aug. 8, 2011, which is a continuation of U.S. patent application Ser. No. 12/476,693, to Graves et al., entitled “OPTICAL SWITCH WITH POWER EQUALIZATION,” filed Jun. 2, 2009, which issued as U.S. Pat. No. 7,995,919 and which is a divisional of U.S. patent application Ser. No. 09/580,495, to Graves et al., entitled “OPTICAL SWITCH WITH POWER EQUALIZATION,” filed May 30, 2000, which issued as U.S. Pat. No. 7,542,675, all of which are assigned to the assignee of the present invention, and all of which are hereby incorporated by references herein in their entireties.
[0002] The present application is related in subject matter to U.S. Pat. No. 6,606,427 B1 to Graves et al., entitled “SWITCH FOR OPTICAL SIGNALS,” issued Aug. 12, 2003, assigned to the assignee of the present invention and hereby incorporated by reference herein in its entirety.
[0003] The present application is also related in subject matter to the U.S. Pat. No. 6,871,021 B2 to Graves et al., entitled “OPTICAL SWITCH WITH CONNECTION VERIFICATION,” issued Mar. 22, 2005, assigned to the assignee of the present invention and hereby incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0004] The present invention relates generally to systems used for switching optical wavelength channels in a wavelength division multiplexed (WDM) network and, more particularly, to optical 25 switches and cross-connects which are required to be equipped with power equalization functionality for controlling the power of individual carriers in a WDM signal.
BACKGROUND OF THE INVENTION
[0005] The principle of wavelength division multiplexing consists of transporting, on a single optical waveguide such as a fiber, a plurality of independent data signals which respectively modulate a plurality of optical carriers occupying distinct optical wavelengths. This allows for significant savings when it is desired to increase the capacity of a network that already has optical fiber in place but where the fiber was previously used for transporting only a single optical carrier occupying a single optical wavelength. Since an optical carrier is implicitly associated with an optical wavelength, the expressions “optical carrier” and “optical wavelength” will hereinafter be used interchangeably.
[0006] In a wavelength division multiplexed (WDM) network, each optical carrier is associated with its own source and destination nodes. Where multiple optical carriers have intersecting routes, these multiple optical carriers will occupy different wavelengths of light on the same fiber. When this type of multi-carrier signal travels along a long route, amplifiers will be required at every 80 kilometers or so in order to boost the signal's optical power.
[0007] On even longer routes, a multi-carrier optical signal may not just suffer severe attenuation but it may also become distorted due to effects such as chromatic dispersion, polarization mode dispersion, signal-to-noise ratio degradation resulting from noise contributions of multiple cascaded amplifiers, and non-linearities in the optical transmission medium or in the optical components traversed along the way.
[0008] Distortion of this nature is sometimes counteracted by inserting equipment in the optical path for providing dispersion compensation or banded gain equalization. In severe cases of distortion, an array of regenerators may need to be added. In its most basic form, a regenerator array detects the data on each incoming carrier and uses the detected digital data to re-modulate a fresh (usually re-shaped and re-synchronized) optical signal on the appropriate optical wavelength. Thus, a regenerator array requires, for each wavelength it is required to regenerate, an optical receiver, electronic re-shaping and re-timing circuitry and an optical source. For a dense wavelength division multiplexing (DWDM) system with typically 32 to 160 wavelengths per fiber, this leads to a very complex regenerator array.
[0009] In order to allow the flexible interconnection of optical carriers, an optical network must be equipped with a mechanism for providing switching functionality at the optical carrier level. Traditionally, an optical interconnect mechanism is implemented either as an optical patch panel or as an electrical switch (or cross-connect) with optical-to-electrical converters at its input and electrical-to-optical converters at its output.
[0010] A cross-connect differs from an switch in that for the case of a cross-connect, the connection map is usually provisioned from a central network management tool, either automatically or manually, whereas for the case of an optical switch, the connection map can be controlled in real time and may even be controlled by the traffic content through the switch, in which case the switch is said to be self-routing. In the interest of simplicity, and because a switch inherently encompasses a cross-connect as well as a switch in the strict sense of the term, references made to a switch in the remainder of the specification should be understood to mean a cross-connect or a switch, depending on the circumstances.
[0011] While an electrical switch provides adequate switching functionality for a low density of wavelength division multiplexing, i.e., to a small number of optical carriers per fiber, those skilled in the art will appreciate that as the density of a WDM optical network grows, it becomes prohibitively expensive (both pecuniarily and from the point of view of power consumption) to equip an electrical switch with sufficient optical-to-electrical and electrical-to-optical conversion resources to handle multiple incoming dense WDM signals arriving on their respective optical fibers.
[0012] To this end, the art has seen the development of the “photonic” switch (or cross-connect), which is the counterpart to the electrical switch (or cross-connect). In a photonic switch, switching is performed almost purely in the optical domain with only minimal recourse to optical-to-electrical or electrical-to-optical conversion. This advantageously results in significant reductions to the cost and complexity of the switching equipment.
[0013] A photonic switch can take on many generic forms, one of which is shown in FIG. 1 and more fully described in above-referenced co-pending U.S. patent application Ser. No. 09/511,065. The photonic switch 100 typically comprises N individual M-output wavelength division demultiplexing (WDD) devices 110 A - 110 N , where each WDD device is associated with a respective one of N input fibers 120 connected to a respective set of N amplifiers 125 . The photonic switch 100 also comprises N individual M-input wavelength division multiplexing (WDM) devices 130 A - 130 N , one WDM device for each of N output optical fibers 140 connected to a respective set of N amplifiers 145 .
[0014] The photonic switch 100 also comprises a photonic switch core 150 connected between the WDD devices 110 A - 110 N and the WDM devices 130 A - 130 N and a switch controller 160 connected to the photonic switch core 150 .
[0015] On the input side of the photonic switch 100 , each of the N WDD devices 110 A - 110 N accepts a respective input WDM signal on a respective one of the input optical fibers 120 . Each of the N WDD devices 110 A - 110 N then separates the respective input WDM signal on a per-wavelength basis into a plurality (M) of input individual optical carrier signals which are provided to an input side of the photonic switch core 150 along a respective plurality (M) of demuxed input optical paths 170 , which may consist of optical fibers, silica waveguides or other optical transmission media.
[0016] The photonic switch core 150 switches the input individual optical carrier signals, thereby to produce a plurality of switched individual optical carrier signals which are carried out of the photonic switch core 150 by a plurality of demuxed switched optical paths 180 . The switch controller 160 generates a connection map under external or locally generated stimulus, which connection map is provided to the photonic switch core 150 and defines the desired map of the optical channels from the input side to the output side of the photonic switch core 150 . External stimulus may be provided via a control link 165 .
[0017] At the output of the photonic switch core 150 , each of the WDM devices 130 A - 130 N receives a respective set of demuxed switched optical paths 180 and combines the switched individual optical carrier signals thereon into a single respective WDM signal that exits the photonic switch 100 along a respective one of the output optical fibers 140 .
[0018] In the illustrated embodiment, the photonic switch core 150 comprises a wavelength converting switch 190 and M optical switch matrices 150 A - 150 M , one for each of the M optical wavelengths in the system. Each optical switch matrix has a set number of input ports and output ports and can be a Micro-Electro-Mechanical System (MEMS) device as described in “Free-Space Micromachined Optical-Switching Technologies and Architectures” by Lih Y. Lin of AT&T Labs-Research during OFC99 Session W14-1 on Feb. 24, 1999. This article is incorporated by reference herein. Such a MEMS device comprises a set of mirrors that are arranged in geometrical relationship with the input and output ports such that incoming light from any input port can be diverted to any output port by erecting an appropriate one of the mirrors under control of the switch controller 160 .
[0019] In FIG. 1 , each of the optical switch matrices 150 A - 150 M has a total of K+N input ports and K+N output ports where, it is recalled, N is the number of WDD devices 110 A - 110 N and WDM devices 130 A - 130 N . For each of the optical switch matrices 150 A - 150 M , each of the N input ports will be connected to the like-wavelength output port of a respective one of the WDD devices 110 A - 110 N , while each of the N output ports will be connected to the like-wavelength input port of a respective one of the WDM devices 130 A - 130 N . This permits optical signals of a given wavelength entering a switch matrix 150 A - 150 M to be connected to the appropriate port of any of the exiting WDM devices 130 A - 130 N .
[0020] It is thus noted that each of the optical switch matrices 150 A - 150 M has K more input ports and K more output ports than are required to switch the N corresponding input individual optical carrier signals (one of which arrives from each of the N WDD devices 110 A - 110 N ). These additional ports are connected to the wavelength converting switch 190 , with two important consequences. Firstly, optical carrier signals arriving on demuxed input optical paths 170 can be redirected towards the wavelength converting switch 190 . Secondly, optical carrier signals arriving from the wavelength converting switch 190 can be output onto one of the demuxed switched optical paths 180 .
[0021] The net result is that a signal on an individual optical carrier is allowed to change wavelengths on its way through the photonic switch 100 by a process which involves optical reception, opto-electronic conversion, electrical switching of the converted electrical signal to an optical source at a desired wavelength and modulation of that source's optical output. The wavelength conversion process is particularly useful when an input wavelength is already in use along the fiber path leading to a destination WDM device.
[0022] It should further be noted that the wavelength converting switch 190 also accepts a plurality of “add carriers” on a plurality (R) of add paths 192 and outputs a plurality of “drop carriers” on a plurality (R) of drop paths 194 . Thus, it is seen that the wavelength converting switch 190 has a total of ((K×M)+R) inputs and a like number of outputs. Structurally, the wavelength converting switch 190 comprises a set of ((K×M)+R) electrical-to-optical converters, an electrical switch and a set of ((K×N)+R) optical-to-electrical converters that collectively function as a miniature version of an electrical switch for optical signals.
[0023] The term “wavelength converting switch” will hereinafter be used throughout the following, with the understanding that such a switch may have either purely wavelength conversion capabilities or both wavelength conversion and add/drop capabilities.
[0024] In operation, the photonic switch 100 of FIG. 1 provides purely optical switching at the optical switch matrices 150 A - 150 M and wavelength conversion (most commonly through the use of electrical switching) at the wavelength converting switch 190 . Control of which input individual optical carrier signals are redirected into the wavelength converting switch 190 is provided by the switch controller 160 . The switch controller 160 also provides control of the switching executed inside the wavelength converting switch 190 .
[0025] With the assistance of network-level control of the wavelengths used by the various sources in the network, it is usually possible to ensure that most wavelengths can transit directly across most nodes in the network without wavelength conversion, hence ensuring that the majority of optical carriers will be sent along the desired output optical fiber 140 directly by the optical switch matrices 150 A - 150 M without involving the wavelength converting switch 190 . As a result, it is usually possible to achieve a minimal blocking probability at the photonic switch 100 by selecting a relatively small value for K, i.e., by keeping most of the switching entirely in the optical domain.
[0026] The photonic switch described in part herein above and described in more detail in co-pending U.S. patent application Ser. No. 09/511,065 is an example of how developments in the field of optical switching are often stimulated by the need to accommodate the ever increasing optical wavelength density of WDM networks in general and WDM signals in particular.
[0027] In addition, the increase in density has driven up the cost associated with providing optical signal regeneration. This is largely due to the higher number of optical sources and receivers which must be provided at a regenerator site in order to handle the increased number of optical carriers per fiber, since each optical carrier has to be regenerated separately and independently. Consequently, those skilled in the art have begun to concentrate on lowering the cost of regeneration by trying to expand the reach between optical regeneration points in a dense WDM network.
[0028] The reach between optical regeneration points is limited by the build-up of degradation suffered by the optical carriers in the WDM signal which cannot be removed (and may actually be introduced) by current optical amplifiers. Specifically, the maximum reach attainable between first and second regeneration points is limited by factors such as:
launch power and pulse shape at the first regeneration point; receiver sensitivity at the second regeneration point; build-up of uncompensated chromatic dispersion and polarization mode dispersion along the route; accumulation of noise arising from cascades of intervening amplifiers; excessive flat gain or loss of intervening amplifiers, WDM/WDD elements, connectors, splices and fibers; wavelength-dependent gain or loss through intervening amplifiers, WDM/WDD elements, connectors, splices and fibers; and cross-modulation and inter-modulation effects.
[0036] Many of the above factors contribute to producing a non-flat optical power spectrum of the WDM signal, i.e., the individual optical carriers will experience different amounts of gain and loss as they propagate. The resulting WDM signal with a non-flat optical power spectrum will reduce the maximum reach because optical carriers having higher power may saturate the intervening optical amplifiers, while optical carriers having lower power may not be detected with sufficient accuracy by a far-end regenerator. Consequently, the power differential between high power carriers and low power carriers has to be minimize in order to maximize the reach between regenerators.
[0037] In attempting to solve this problem, it has been realized that for a conventional point-to-point WDM system, variations in the optical power of the component carriers of a WDM signal are often correlated between one optical carrier and its neighbours in the optical spectrum, due to having undergone a common, wavelength-dependent amplitude distortion process. Conventional spectrum flattening techniques take advantage of this realization to provide “band equalization” of the power spectrum at an intermediate component between two regenerators. This type of equalization technique is now described with reference to FIG. 2 .
[0038] Specifically, a band WDD device 4 may be used to separate an original WDM signal arriving on an input optical fiber 2 into a plurality of separate optical paths each consisting of a number of signals occupying mutually exclusive optical frequency bands. For simplicity of illustration, there are three groups of signals occupying three bands denoted A, B, C, but there may be five bands in a typical band equalization scenario. The three separated groups of signals are still WDM signals in their own right but have fewer carriers than the original WDM signal.
[0039] Each of the three signals in bands A, B, C passes through a respective one of a plurality of variable optical intensity controllers (VOICs) 6 , 8 , 10 . Each of the VOICs 6 , 8 , 10 could be an amplifier or an attenuator having a response which is controllable within the band of interest but is irrelevant elsewhere. The outputs of the three VOICs 6 , 8 , 10 are then recombined by a band WDM device 12 into a recombined WDM signal provided on an output optical fiber 14 .
[0040] In FIG. 2 , the optical power spectrum of the original WDM signal on the input optical fiber 2 is shown at 16 and, in this example, is seen to comprise a total of fifteen optical carriers, five in each of the three broad optical frequency bands A, B, C. The correlation among the power levels of neighbouring carriers in the input optical power spectrum 16 is apparent from the diagram.
[0041] In addition, it is seen that the overall peak-to-peak power level variation (shown at 18 ) of the input optical power spectrum 16 is significant. However, because of the correlation among the power levels of neighbouring carriers, it is possible to identify an average power level 19 A , 19 B , 19 c in each respective band such that the peak-to-peak power level variation with respect to that average power level in that band is reduced as compared to the overall peak-to-peak power level variation 18 .
[0042] In order to achieve band equalization, the gain (or attenuation) to be applied by each of the VOICs 6 , 8 and 10 is set to a value which complements the estimated average power level in the corresponding band in order to bring the average power level to a target level. Since the band equalization is usually a static technique, average power level estimates can be obtained at installation time. In the case of FIG. 2 , comparing the average power levels 19 A, 19 B and 19 C in bands A, B and C (which can be estimated at installation time), it is seen that VOIC 6 should be accorded a moderate gain, VOIC 8 should be accorded a high gain and VOIC 10 should be accorded a low gain.
[0043] After applying band equalization in the manner of FIG. 2 , the optical power spectrum (shown at 20 ) of the recombined WDM signal provided on the output optical fiber 14 is seen to have a significantly lower overall peak-to-peak power level variation (shown at 22 ) when compared to the overall peak-to-peak variation 18 in the original WDM signal.
[0044] However, it will be apparent that the band equalization approach does not completely remove peak-to-peak variations in the optical power spectrum of the original WDM signal. Rather, it provides a mechanism for reducing the level of variation and results in this level of reduction being traded off against implementational complexity by exploiting the correlation existing between adjacent carriers. Therefore, as seen in FIG. 2 , the resultant WDM signal travelling on the output optical fiber 14 still contains wavelength-dependent variations in its optical power spectrum 20 .
[0045] Furthermore, the band equalization technique illustrated in FIG. 2 does not account for wavelength-dependent power level variations which may have been introduced by the band demultiplexer 4 and the band multiplexer 12 . Although not explicitly shown in FIG. 2 , the optical power spectrum 20 of the output WDM signal could conceivably contain even more significant variations due to the compounded effects of the band demultiplexer 4 and the band multiplexer 12 .
[0046] A further cause of variance in the optical power spectrum of a WDM signal is the action of a photonic switch such as that shown in FIG. 1 . Specifically, because the connection map of the photonic switch is arbitrary, being driven by traffic connectivity considerations rather than optical link considerations. Thus, a particular output WDM signal emerging from the photonic switch will contain optical carriers that will likely have travelled along entirely different paths through the network. Each of these paths is associated with its own loss characteristics and therefore the various individual optical carrier optical signals that make up a WDM signal at the output of the photonic switch will have respective optical power level which are uncorrelated with one another.
[0047] The situation is illustrated in FIG. 3 , where a 3×3 photonic switch 300 is connected to three input optical fibers 40 , 42 , 44 and three output optical fibers 60 , 62 , 64 . The input optical power spectrum of the WDM signal on each of the input optical fibers 40 , 42 , 44 is shown at 50 , 52 , 54 , respectively. Each of these three input optical power spectra 50 , 52 , 54 occupies the same optical frequency range but has a distinct shape. In particular, the shape of each of the optical power spectra 50 , 52 , 54 displays a certain degree of correlation among the power levels of neighbouring carriers. For example, spectrum 50 has a monotonically decreasing shape, spectrum 52 has a bell shape and spectrum 54 is composed of relatively constant power levels.
[0048] Since any arbitrary connection map may be provided by the photonic switch 300 at a given instant in time, the correlations existing among the carrier power levels on a the input optical fibers 40 , 42 , 44 may not carry through to the output optical fibers 60 , 62 , 64 . Hence, the output optical spectra (shown at 70 , 72 , 74 ) will exhibit a poor correlation among individual carriers and will appear “randomized”. This effect may be compounded by differing losses experienced by the various signals as they transit the switch node components. Clearly, as a result of this lack of correlation among individual carriers, a band equalization technique such as that previously described with reference to FIG. 2 would be of little use if applied at the output or even at the input of the photonic switch 300 .
[0049] Those skilled in the art will also appreciate that in addition to being affected by spectral variations arising from the arbitrary connection map applied by a photonic switch, the optical power spectrum of an output WDM signal may be further distorted by wavelength-dependent losses induced by a WDM device positioned at the output of the switch and, to a certain extent, by path-dependent losses through the photonic switch core.
[0050] Hence, it will be appreciated that the optical power spectrum of the WDM signals exiting a photonic switch can be severely distorted and, worse still, the distortion has no predictable spectral shape. Moreover, the optical power spectrum of the WDM signals can change dramatically and suddenly with each change in the connection map. Clearly, such wavelength-dependent distortion presents a serious limitation on the reach between the photonic switch and the next regeneration point in the network and therefore it would be a tremendous advantage to provide spectral flattening at the photonic switch, without adding significant complexity to the design of the photonic switch itself.
SUMMARY OF THE INVENTION
[0051] The present invention is directed to providing each signal at the output of a photonic switch with a controllable (e.g., flat) optical power spectrum, while only slightly increasing the complexity of the switch design. The equalization system, or “equalizer”, of the present invention controllably adjusts the optical power of each individual optical signal passing through the photonic switch by placing a plurality of variable optical intensity controllers (VOICs) in each optical path prior to wavelength recombination. The VOICs can be variable optical amplifiers or variable optical attenuators. The VOICs are controlled by a controller which derives power estimates from individual optical carrier signals extracted from the WDM signals at the output of the photonic switch.
[0052] In this way, many advantages are achieved. Firstly, individual and independent control of the power on each optical channel is provided. Secondly, wavelength-dependent losses introduced by all the devices in the switch including the WDM devices at the output of the switch are accounted for. Thirdly, tapping the output WDM signals requires only one optical coupler for each output optical fiber, reducing the complexity of the equalization system. Fourthly, tapping the output WDM signals at the output of the switch has no effect on the system's noise floor.
[0053] In some embodiments of the invention, coarse equalization is provided for each multiplexed optical signal either at the input to the switch or at the output of the switch. This permits a reduction in the dynamic range over which the VOICs are required to operate, which advantageously allows the use of cheaper components.
[0054] In other embodiments of the invention, the controller in the equalizer will reduce the intensity of the individual optical signals that are effected by a forthcoming change in the connection map of the switch. The intensity is then gradually increased to a reference value once the new connection map is applied. This mapping procedure prevents existing carriers from being effected by sudden power level changes to other carriers sharing the same output optical fiber and optical amplifier chain.
[0055] In still other embodiments, the invention provides a calibration functionality. This can be achieved by evaluating the relative loss of each possible fiber/wavelength combination through the front end of the equalizer. In this way, spectral variations due to tolerances in the equalizer can be significantly reduced.
[0056] In a broad sense, the invention may be summarized as an optical intensity control system for use with an optical switch providing individual signal paths between a plurality of input ports and a plurality of output ports. The switch typically has a plurality of wavelength division multiplexers for combining sets of individual switched optical signals into multiplexed switched optical signals.
[0057] The intensity control system of the invention is equipped with a plurality of optical splitters, each being connectable to an output of a respective one of the wavelength division multiplexers and a plurality of variable optical intensity controllers (VOICs) for insertion into respective ones of the individual signal paths and for individually controlling the intensity of optical signals present in the respective ones of the individual signal paths in accordance with respective intensity control signals.
[0058] The intensity control system of the invention is further equipped with an equalizer connected to the splitters and to the VOICs, for producing an estimate of the optical power of each individual switched optical signal and generating the intensity control signals as a function of the estimates of optical power. This allows the optical powers of each of the carriers to be changed, resulting in a substantially equal power in each optical carrier.
[0059] The equalizer may have a front end circuit with a plurality of inputs for receiving the multiplexed switched optical signals, where the front end circuit is adapted to controllably isolate individual switched optical signals from the multiplexed switched optical signals. The equalizer also has an optical receiver unit connected to the front end circuit, for converting any isolated individual switched optical signals to electrical signals. The equalizer is further equipped with a power estimation unit connected to the optical receiver unit, for time-averaging the electrical signals, thereby to obtain respective estimates Of optical power. Finally, the equalizer has a processor connected to the power estimation unit and to the front end circuit, where the processor is adapted to cause the front end circuit to isolate selected individual switched optical signals and also to generate the intensity control signals from the estimates of optical power.
[0060] In some embodiments, front end circuit has wavelength-tunable optical bandpass filters connected to outputs of the optical splitters. The processor is then adapted to selectably tune the filters in order to cause individual switched optical signals to be selected on the basis of fiber origin and individual wavelength.
[0061] In other embodiments, the front end circuit is equipped with an optical switch matrix having a plurality of inputs respectively connected to the plurality of splitters and having a plurality of controllably erectable mirrors, as well as a wavelength division demultiplexer connected to an output of the switch matrix. In this case, the processor is adapted to selectably raise one mirror at a time on the optical switch matrix in order to cause selected individual switched optical signals to be isolated.
[0062] The front end circuit may alternatively comprise a first optical switch matrix having a plurality of inputs respectively connected to the plurality of splitters and having a plurality of controllably erectable mirrors, as well as a wavelength division demultiplexer connected to an output of the first switch matrix and at least one second optical switch matrix, where each second optical switch matrix has a plurality of inputs connected to the wavelength division demultiplexer and having a plurality of controllably erectable mirrors. The processor would then be adapted to selectably raise one mirror at a time on the first optical switch matrix and to raise one mirror at a time on the at least one second optical switch matrix in order to cause selected individual switched optical signals to be isolated.
[0063] In still other cases, the front end circuit has (1) a first optical switch matrix having a plurality of inputs respectively connected to the plurality of splitters and having a plurality of controllably erectable mirrors, (2) a wavelength division demultiplexer connected to an output of the first switch matrix, (3) at least one second optical switch matrix, each the second optical switch matrix having a plurality of inputs connected to the wavelength division demultiplexer and having a plurality of controllably erectable mirrors and (4) a coupler connected to an output of each second optical switch matrix.
[0064] The invention may also be broadly summarized as a method of generating control signals for adjusting the intensity of single-carrier optical signals travelling through an optical switch, wherein groups of individual switched optical signals are recombined into multiplexed switched optical signals at an output end of the switch. The method includes the steps of:
(a) controllably isolating individual switched optical signals from the multiplexed switched optical signals; (b) estimating the power of the individual switched optical signals isolated at step (a); and (c) generating the control signals as a function of the power estimates obtained at step (b) and a reference value.
[0068] The invention can also be broadly summarized as a switch for optical signals, which has wavelength division demultiplexers, wavelength division multiplexers, optical splitters connected to the multiplexer output port of a respective one of the wavelength division multiplexers, a switching core connected between the wavelength division demultiplexers and the wavelength division multiplexers, a plurality of variable optical intensity controllers (VOICs) positioned in respective ones of the optical paths, and an equalizer as described above, connected to the couplers and to the VOICs.
[0069] The switching core may comprise a plurality of core optical switching matrices, each core optical switch matrix being associated with a distinct optical wavelength. The switching core may further comprise a wavelength-converting inter-matrix switch connected to the core optical switching matrices, for receiving optical signals from the core optical switching matrices, converting each received optical signal to electrical form and transmitting each converted signal at a changed wavelength to the core optical switch matrix associated with the changed wavelength.
[0070] If optical switch matrices are used in the equalizer, at least one such optical switch matrix can be in a stacked relationship with respect to one or more core optical switch matrices to improve compactness.
[0071] The invention may also be summarized broadly as a method of calibrating power estimates received at a processor connected to an optical carrier selection circuit in an intensity control loop. The method includes the steps of:
[0072] obtaining a reference estimate of the optical power of a reference light source without the effect of the optical carrier selection circuit;
[0073] controlling the optical carrier selection circuit in order to obtain an estimate of the optical power of the reference light source for each of a plurality of possible optical paths through the optical carrier selection circuit;
[0074] generating a calibration factor for each path by evaluating a function of the difference between the corresponding received power estimate and the reference estimate; and
[0075] adjusting subsequent power estimates for each path by the corresponding calibration factor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0076] These and other aspects and features of the present invention will now become apparent to those of ordinary skill in the art upon review of the accompanying description of specific embodiments of the invention in conjunction with the following drawings, in which:
[0077] FIG. 1 , already described, shows a photonic switch in block diagram form;
[0078] FIG. 2 , already described, shows in block diagram form an implementation of a band equalization technique;
[0079] FIG. 3 , already described, shows the effects of a photonic switch on the power spectrum of a WDM signal at the output of the photonic switch;
[0080] FIG. 4 shows in block diagram form part of a photonic switch in accordance with an embodiment of the present invention;
[0081] FIGS. 5 through 9 show, in block diagram form, specific embodiments of an equalizer forming part of the photonic switch of FIG. 4 ;
[0082] FIG. 10 shows a message flow diagram between controllers inside and outside the equalizer under transient conditions;
[0083] FIG. 11 is a table illustrating a comparative summary of the component requirements of the embodiments of FIGS. 5 through 9 ;
[0084] FIG. 12 is a block diagram of an embodiment of the photonic switch of the invention which uses coarse intensity control at the input to the switch;
[0085] FIG. 12A shows a variation of the embodiment of FIG. 12 ;
[0086] FIG. 13 is block diagram of another embodiment of the photonic switch of the invention which uses coarse intensity control at the input to the switch;
[0087] FIG. 14 is a block diagram of an embodiment of the photonic switch of the invention which uses coarse intensity control at the output of the switch;
[0088] FIG. 15 is a block diagram of an embodiment of the photonic switch of the invention with calibration functionality; and
[0089] FIG. 16 shows the application of calibration functionality to the embodiment of FIG. 12A .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0090] With reference to FIG. 4 , there is shown a photonic switch 400 according to an embodiment of the present invention. The photonic switch 400 resembles the photonic switch 100 of FIG. 1 in that it retains the basic structure including the WDD devices 110 A - 110 N , the WDM devices 130 A - 130 N and the photonic switch core 150 .
[0091] The photonic switch 400 of the invention additionally comprises a plurality (M×N) of variable optical intensity controllers (VOICs) 410 respectively positioned in each of the demuxed switched optical paths 180 . Thus, each of the VOICs 410 is associated with a respective switched individual optical carrier signal that emerges from the photonic switch core 150 along a respective one of the demuxed switched optical paths 180 .
[0092] The VOICs 410 are used for providing intensity control in the form of either attenuation or amplification. Thus, each of the VOICs 410 can either be a variable optical attenuator or a variable optical amplifier, depending on the operational requirements of the invention. The range of intensity control (i.e., attenuation or gain) required of an individual VOIC is typically expected to be on the order of 8 decibels (dB) or less, although it is within the scope of the invention to provide a greater or smaller dynamic range of attenuation or gain.
[0093] It is convenient to view the VOICs 410 as forming an array of size M×N where, it is recalled, N is the number of WDM devices 130 A - 130 N and M is the number of wavelengths handled by each WDM device (which is also the number of optical switch matrices 150 A - 150 H in the photonic switch core 150 ). Typical values for M are 32 and above, while typical values for N are 4 and above. However, it should be understood that the invention is not subject to any limitation on M or N.
[0094] Each of the VOICs 410 has a control port for receiving a respective intensity control signal along a respective one of a plurality of intensity control lines generally indicated by the reference numeral 415 . Each such intensity control line carries an intensity control signal indicative of a desired amount of attenuation or gain to be applied by the respective VOIC. The intensity control line leading to the VOIC corresponding to the J th optical switch matrix 150 J and the K th WDM device 130 K can be denoted 415 J,K , where Jε{A, B, . . . , M} and Kε{A, B, . . . , N}.
[0095] With continued reference to FIG. 4 , the photonic switch 400 of the invention further comprises a plurality (N) of directional couplers 420 (also referred to as optical splitters), each of which intercepts the optical path of a respective one of the N output optical fibers 140 . It is noted that the number of couplers 420 is equal to the number of output optical fibers 140 , which is M times less than the total number of demuxed switched optical paths 180 .
[0096] It should be understood that the couplers (splitters) 420 could be placed after the amplifiers 145 (as shown) or in front of the amplifiers 145 , depending on the operational requirements of the invention. For instance, if it is important to allow openness so that 3 rd party amplifiers 145 can be used, then it is desirable to place the couplers 420 in front of the amplifiers 145 . However, such a configuration would not permit the power spectrum equalizer 500 to compensate for spectral gain variations introduced by the amplifiers 145 . Therefore, to compensate for such variations, it would be advantageous to place the couplers 420 after the amplifiers 145 .
[0097] Each of the N couplers 420 can be a standard component which is designed to tap a small, known amount of optical power from the respective output optical fiber 140 . A suitable amount of optical power tapped in this manner will be 10 dB to 13 dB below the optical power level on the respective output optical fiber 140 . This lowers the optical power level of the ongoing signal by only 0.22 dB to 0.46 dB, which loss can then be compensated for by increasing the gain of the respective amplifier (when the couplers 420 are placed in front of the amplifiers 145 ) or by increasing the gain (decreasing the attenuation) of the VOICs 410 associated with that amplifier.
[0098] The photonic switch 400 of the present invention further comprises a power spectrum equalization control system (hereinafter simply referred to as an “equalizer”) 500 which is placed between the couplers 420 and the VOICs 410 and which communicates with a switch controller 160 ′ via a control line 440 . The switch controller 160 ′ is similar to the switch controller 160 in FIG. 1 with additional special operational features that will be described later on. As with the switch controller 160 of FIG. 1 , the switch controller 160 ′ of FIG. 4 communicates with the outside world by a control link 165 .
[0099] The equalizer 500 is connected to each of the N couplers 420 by a respective one of a plurality of optical paths 425 A - 425 N , where optical path 425 A carries a tapped WDM optical signal from WDM device 130 A , optical path 425 B carries a tapped WDM optical signal from WDM device 130 B , and so on. The equalizer 500 is further connected to the control port of each of the M×N VOICs 410 by a respective one of the plurality of intensity control lines 415 .
[0100] The equalizer 500 may have a variety of internal configurations, some of which will be described in further detail later on. A feature common to each structure is the provision of suitable circuitry, software and/or control logic for:
receiving tapped optical signals from the couplers 420 along the optical paths 425 A - 425 N ; processing the tapped optical signals according to an algorithm (still to be described); and generating intensity control signals to be supplied to the M×N individual VOICs 410 via the M×N intensity control lines 415 .
[0104] Thus, the equalizer 500 controls the amount of gain or attenuation to be applied by each of the VOICs 410 . This is done with the aim of flattening the optical power spectrum of each output WDM signal.
[0105] Specific embodiments of the equalizer 500 are now described with reference to FIGS. 5 , 6 , 7 , 8 and 9 . In FIG. 5 , the equalizer 500 is seen to comprise N individual M-output WDD devices 510 A - 510 N , each of which is connected to a respective one of the couplers 420 via a respective one of the optical paths 425 A - 425 N . Each of the WDD devices 510 A - 510 N is designed to separate the received, coupled version of the respective output WDM signal into its M individual optical carrier components. Therefore, the M signals at the output of each of the WDD devices 510 A - 510 N correspond to the M switched individual optical carrier signals as combined by the respective one of the WDM devices 130 A - 130 N .
[0106] Each of the WDD devices 510 A - 510 N is connected to a respective set of M optical receivers. For notational convenience, the particular optical receiver associated with the switched individual optical carrier signal carried along one of the demuxed switched optical paths 180 from the J th optical switch matrix 150 J to the K th WDM device 130 K can be denoted 520 J,K . Thus, in FIG. 5 , WDD device 510 A is connected to optical receivers 520 A,A , 520 B,A , 520 M,A , WDD device 510 B is connected to optical receivers 520 A,B , 520 B,B , 520 M,B , etc., and WDD device 510 N is connected to optical receivers 520 A,N , 520 B,N , 520 M,N .
[0107] The optical receivers (collectively denoted by 520 ) each comprise circuitry such as a photodiode and a trans-impedance amplifier for converting into electrical form an optical signal present at its input. In the embodiment of FIG. 5 , the signal received at the input to a given optical receiver is always at the same wavelength, and therefore each of the optical receivers 520 can be a narrow-optical-bandwidth component tuned to the appropriate optical wavelength.
[0108] The M×N optical receivers 520 are respectively connected to a plurality (M×N) of power estimation modules. The individual power estimation module connected to optical receiver 520 J,K for a particular value of J and K can be denoted by 530 J,K . Thus, the power estimation module denoted by 530 A,A is connected to optical receiver 520 A,A , and so on.
[0109] Each of the power estimation modules (collectively denoted by 530 ) comprises circuitry, firmware or control logic for estimating the power of the optical signal from which the electrical signal received from the respective one of the optical receivers 520 was derived. Since optical power is directly proportional to optical intensity, suitable power estimation circuitry could include circuitry for measuring the average voltage of the received electrical signal, from which the optical power can be determined. Of course, those skilled in the art will be familiar with other methods of power estimation. Furthermore, sampling and digitizing operations can be performed either prior or subsequent to power estimation.
[0110] It will also be appreciated that as long as the digital signal on each optical wavelength has a duty cycle of approximately 50% (i.e., has an approximately equal number of zeroes and ones over a pre-determined integration interval), the receivers 520 and power estimation modules 530 can be low-speed components for measuring average power over such an integration interval.
[0111] With continued reference to FIG. 5 , the power estimate produced by each of the power estimation modules 530 is provided to a respective input of a controller 550 . In the embodiment of FIG. 5 , the controller 550 is equipped with a M×N-input multiplexer 552 which is connected to a processor 554 . The processor 554 selectively reads the power estimates through control of the multiplexer 552 via a control line.
[0112] The processor 554 comprises suitable circuitry, software and/or control logic for processing the power estimates received from the power estimation modules 530 and generating intensity control signals for transmittal to the VOICs 410 along the intensity control lines 415 . Operation of the processor 554 in accordance with an equalization algorithm will be described in further detail later on.
[0113] As shown in FIG. 5 , the processor 554 may be connected to the VOICs by a plurality (M×N) of latches 556 and an intervening demultiplexer 558 . Thus, the processor 554 may provide the intensity control signals one at a time to the demultiplexer 558 along a single signal line. Under control of the processor 554 , the demultiplexer 558 then sends the received intensity control signal to the appropriate one of the latches 556 , where the present value of the intensity control signal is held until further notice.
[0114] Another specific embodiment of the equalizer 500 is shown in FIG. 6 . In this case, the equalizer 500 comprises a plurality of wavelength-tunable optical bandpass filters 610 A - 610 N , each of which is connected to a respective one of the couplers 420 via a respective one of the optical paths 425 A - 425 N . A wavelength-tunable optical bandpass filter is a known component which passes a selectable optical frequency range of an input signal as a function of a control voltage or current supplied to the filter. Thus the need for WDD devices at the input to the equalizer 500 can be avoided, while reducing the total required number of optical receivers and power estimation modules.
[0115] Specifically, the output of each of the wavelength-tunable optical bandpass filters 610 A - 610 N is connected to a respective one of a plurality of optical receivers 620 A - 620 N , each of which is similar to one of the optical receivers 520 previously described with reference to FIG. 5 . However, because the signal input to any one of the N optical receivers 620 A - 620 N may occupy any one of the M possible wavelengths in the system, the optical receivers 620 A - 620 N must each be operable over a wider optical bandwidth, typically the entire WDM spectrum.
[0116] Each of the optical receivers 620 A - 620 N has an output which is connected to a respective one of a plurality of power estimation modules 530 A - 530 N , each of which is identical to any of the power estimation modules suitable for use in the equalizer of FIG. 5 . The power estimation modules 530 A - 530 N are connected to respective inputs of a controller 650 . In the embodiment of FIG. 6 , the controller 650 is equipped with an N-input multiplexer 652 which is connected to a processor 654 . The processor 654 selectively reads the power estimates through control of the multiplexer 652 via a control line.
[0117] The processor 654 comprises suitable circuitry, software and/or control logic for processing the power estimates received from the power estimation modules 630 and generating intensity control signals for transmittal to the VOICs 410 along the intensity control lines 415 . In addition, the controller 650 comprises a filter driver 656 for varying, under control of the processor 654 , the pass band of the wavelength-tunable optical bandpass filters 610 A - 610 N via a respective plurality of control lines 615 A - 615 N . Operation of the processor 654 in accordance with an equalization algorithm will be described in further detail later on.
[0118] The processor 654 may be connected to the VOICs by a plurality (M×N) of latches 556 and an intervening demultiplexer 556 . Thus, the processor 654 provides the intensity control signals one at a time to the demultiplexer. 558 along a single signal line. Under control of the processor 654 , the demultiplexer 558 then sends the received intensity control signal to the appropriate one of the latches 556 , where the present value of the intensity control signal is held until further notice.
[0119] Another specific embodiment of the equalizer 500 is shown in FIG. 7 , wherein the optical paths 425 A - 425 N lead to respective inputs of an N-input optical switch matrix 710 (e.g., a MEMS based optical switch matrix as described in the previously referenced article by Lih Y. Lin of AT&T Labs-Research) which can be identical to any one of the switch matrices 150 A - 150 M in FIG. 4 . In this case, only one of the output ports of the optical switch matrix 710 is used and this particular output port is connected to an M-output WDD device 510 . However, it is possible to decrease response and scanning times by using more than one output of the optical switch matrix 710 , with each such output being connected to its own WDD device.
[0120] Within the optical switch matrix 710 there is provided an arrangement of N controllably erectable mirrors 712 A - 712 N . The position of each mirror is either flat (in the plane of the optical switch matrix 710 ) or upright (perpendicular to the plane of the optical switch matrix 710 ), depending on the value of a control signal 714 . When a particular one of the mirrors 712 A - 712 N , say the pth mirror 712 p , is selected to be upright, then light arriving along the corresponding optical path 425 p from the corresponding one of the couplers 420 will be directed to the output of the optical switch matrix 710 and into the WDD device 510 .
[0121] The WDD device 510 is identical to the WDD devices 510 A - 510 N of FIG. 5 and thus is designed to separate the received optical signal (arriving from the optical switch matrix 710 ) into its M component wavelengths. The signals output by the WDD device 510 arrive at respective ones of a plurality of optical receivers 520 A - 520 M .
[0122] Since each of the optical receivers 520 A - 520 M is dedicated to processing signals having a fixed wavelength, each of the optical receivers 520 A - 520 M can have a narrower optical bandwidth than the receivers 620 A - 620 N in FIG. 6 . Thus, each of the optical receivers 520 A - 520 M can be identical to any of the optical receivers suitable for use in the equalizer of FIG. 5 and is accordingly designated by the same reference character. The number of such optical receivers in the embodiment of FIG. 7 is equal to the number of wavelengths (which is M).
[0123] Each of the optical receivers 520 A - 520 M is connected to a respective one of a plurality of power estimation modules 530 A - 530 M , each of which can be identical to any of the power estimation modules suitable for use in the embodiments of FIGS. 5 and 6 . The number of power estimation modules 530 in the embodiment of FIG. 7 is equal to the number of wavelengths (M). The power estimation modules 530 A - 530 M are connected to respective inputs of a controller 750 . In the embodiment of FIG. 7 , the controller 750 is equipped with an M-input multiplexer 752 which is connected to a processor 754 . The processor 754 selectively reads the power estimates through control of the multiplexer 752 via a control line.
[0124] The processor 754 comprises suitable circuitry, software and/or control logic for processing the power estimates received from the power estimation modules 530 A - 530 M and generating intensity control signals for transmittal to the VOICs 410 along the intensity control lines 415 . In addition, the controller 750 comprises a switch driver 758 for raising, under control of the processor 754 , a selected one of the mirrors 712 A - 712 N in the optical switch matrix 710 . Operation of the processor 754 in accordance with an equalization algorithm will be described in further detail later on.
[0125] As was described earlier with reference to FIGS. 5 and 6 , the processor 754 may be connected to a plurality (M×N) of latches 556 by a demultiplexer 558 . Thus, the processor 754 provides the intensity control signals one at a time to the demultiplexer 558 along a single signal line. Under control of the processor 754 , the demultiplexer 558 then sends the received intensity control signal to the appropriate one of the latches 556 , where the present value of the intensity control signal is held for the respective VOIC until further notice.
[0126] In FIG. 8 is shown yet another embodiment of the equalizer 500 of the present invention, representing an elegant simplification in the design. In this embodiment, there is provided a first N-input optical switch matrix 710 (identical to that of FIG. 7 ) which is connected to a WDD device 510 (identical to those of FIGS. 5 and 7 ). The elevation of a particular mirror in the optical switch matrix 710 is controlled by a control signal received along a control line 714 . The output of the optical switch matrix 710 contains a multi-wavelength optical signal which is split into its M optical carrier components by the WDD device 510 .
[0127] The WDD device 510 is connected to one or more additional N-input optical switch matrices 710 ′. Each of the optical switch matrices 710 ′ consists of an arrangement of controllably erectable mirrors whose position is either flat or upright as controlled by another control signal received along another control line 714 ′. Thus, only one output of each of the optical switch matrices 710 ′ is actually used.
[0128] Of course, in order to use only one N-input optical switch matrix 710 ′, then N (the number of input or output optical fibers) should be greater than or equal to M (the number of wavelengths in the system). Since in many cases this condition cannot be satisfied, it becomes necessary to provide a number of optical switch matrices 710 ′ equal to ceil(M÷N), where ceil(M÷N) represents the smallest integer value not less than the quotient of M and N.
[0129] The case where ceil(M÷N)=2 is shown in FIG. 8 , there being provided two optical switch matrices 710 ′ with the output of each optical switch matrix being coupled together at a coupler 810 . Alternatively, the coupler 810 can be omitted and the output of each of the switch matrices 710 ′ can be provided to a controller 850 via separate paths. In either case, by ensuring that only one of the mirrors on only one of the optical switch matrices 710 ′ is upright at any one time, the multiple optical switch matrices 710 ′ can be made to behave as a single M-input optical switch matrix.
[0130] An advantage of using multiple N-input optical switch matrices 710 ′ rather than one M-input optical switch matrix is that N-input optical switch matrices 710 ′ have the exact same dimensions as the optical switch matrices 150 A - 150 M in the photonic switch core 150 and can be fully integrated therewith. Thus, the optical switch matrices 710 , 710 ′ can be stacked or aligned with respect to the optical switch matrices 150 A - 150 M in the photonic switch core 150 , thereby improving compactness of the switch as a whole.
[0131] The output of the coupler 810 is connected to the optical receiver 620 which can be identical to any of the optical receivers previously described with reference to FIG. 6 , i.e., the optical receiver 620 must have a sufficiently wide optical bandwidth of operation to handle optical carrier signals occupying different wavelengths at different times. If the coupler 810 is dispensed with, then the output of each of the optical switch matrices 710 ′ could be connected to its own wide-optical-bandwidth optical receiver.
[0132] The optical receiver 620 is connected to a power estimation module 530 , which can be identical to any of the power estimation modules suitable for use in the embodiments of FIGS. 5 , 6 and 7 . If the coupler 810 is omitted from the design, then the number of optical receivers and power estimation modules would equal the number of optical switch matrices 710 ′, which is equal to ceil(M÷N).
[0133] The power estimation module 530 is connected to an input of a processor 854 in the controller 850 . The processor 854 comprises suitable circuitry, software and/or control logic for processing power estimates received from the power estimation module 530 and generating intensity control signals for transmittal to the VOICs 410 along the intensity control lines 415 . Moreover, the controller 850 comprises a switch driver 858 for raising, under control of the processor 854 , exactly one of the mirrors 712 A - 712 N in the optical switch matrix 710 and exactly one of the mirrors from among all those in the one or more optical switch matrices 710 ′ connected to the WDD device 510 . This allows the processor 854 to sequentially access the individual power estimates associated with various wavelength-fiber combinations. Operation of the processor 854 in accordance with an equalization algorithm will be described in further detail later on.
[0134] As was described previously with reference to FIGS. 5 through 7 , the processor 854 may be connected to a plurality (M×N) of latches 556 by a demultiplexer 558 . Thus, the processor 854 provides the intensity control signals one at a time to the demultiplexer 558 along a single signal line. Under control of the processor 854 , the demultiplexer 558 then sends the received intensity control signal to the appropriate one of the latches 556 , where the present value of the intensity control signal is held until further notice.
[0135] Still another embodiment of the equalizer 500 is depicted in FIG. 9 , wherein there is provided an N-input optical switch matrix 710 much like any of the previously described optical switch matrices suitable for use in the embodiments of FIGS. 7 and 8 . The selection of which of the mirrors 712 A - 712 N is to be raised is controlled via a control link 714 . An output of the optical switch matrix 710 is connected to a single wavelength-tunable optical bandpass filter 610 much like any of the filters 610 A - 610 N suitable for use with the embodiment of FIG. 6 . Again, the use of more than one output of the optical switch matrix 710 may reduce the response and scanning time associated with measuring the power of the switched individual optical carrier signals travelling through the photonic switch 400 .
[0136] The output of the wavelength-tunable optical bandpass filter 610 is connected to a processor 954 within a controller 950 via a wide-optical-bandwidth optical receiver 620 and a power estimation module 530 . The processor 954 is equipped with suitable circuitry, software and/or control logic for processing power estimates received from the power estimation module 530 and generating intensity control signals for transmittal to the VOICs 410 along the intensity control lines 415 .
[0137] Moreover, the controller 950 comprises a switch driver 958 for raising, under control of the processor 954 , exactly one of the mirrors 712 A - 712 N in the optical switch matrix 710 . In addition, the controller 950 comprises a filter driver 956 for varying, under control of the processor 954 , the pass band of the wavelength-tunable optical bandpass filter 610 via a control link 615 . This allows the processor 954 to sequentially access the individual power estimates associated with various wavelength-fiber combinations. Operation of the processor 954 in accordance with an equalization algorithm will be described in further detail later on.
[0138] As was described previously with reference to FIGS. 5 through 8 , the processor 954 may be connected to a plurality (M×N) of latches 556 by a demultiplexer 558 . Thus, the processor 954 provides the intensity control signals one at a time to the demultiplexer 558 along a single signal line. Under control of the processor 954 , the demultiplexer 558 then sends the received intensity control signal to the appropriate one of the latches 556 , where the present value of the intensity control signal is held until further notice.
[0139] FIG. 11 provides, in tabular form, a comparative summary of the various embodiments of the controller in FIGS. 5 through 9 in terms of the number of components (optical receivers, power estimation modules, optical switch matrices, WDD devices, wavelength-tunable optical bandpass filters) required in order to implement each embodiment. It is seen that the progression of embodiments from FIG. 5 through to FIG. 9 is increasingly intricate yet elegant. The utmost in simplicity and elegance is achieved in the embodiment of FIG. 9 where the equalizer 500 requires only one power estimation module 530 , one wavelength-tunable optical bandpass filter 610 , one wide-optical-bandwidth optical receiver 620 and one N-input switch matrix 710 .
[0140] As has been previously described (with reference to FIG. 8 , for example), the use of N-input optical switch matrices 710 , 710 ′ permits these switch matrices to be integrated into the structure of the photonic switch core 150 . Thus, in designing a card cage for housing the optical switch matrices 150 A - 150 M forming part of the optical switch core 150 , it is within the scope of the invention to provision additional slots not only for use with spare optical switch matrix cards but also for use with the optical switch matrix cards 710 , 710 ′ needed by the equalizer (e.g., 1 spare card for the embodiments of FIGS. 7 and 9 and ceil(M÷N) spare cards for the embodiment of FIG. 8 ).
[0141] Operation of the “equalization processor” is now described. The term “equalization processor” is hereinafter used to refer to any of the processors 554 , 654 , 754 , 854 , 954 previously described with reference to FIGS. 5 , 6 , 7 , 8 , 9 , respectively. In each case, the equalization processor runs an equalization algorithm for processing the power estimates received from the power estimation module(s) 530 and for interacting with the switch controller 160 ′ via the control line 440 .
[0142] The equalization algorithm has two modes of operation, the first mode being a so-called “scan mode”, which is executed under steady-state connection conditions, and the second mode being a so-called “directed mode”, which is entered upon interruption of the equalization controller while it is running in scan mode.
[0143] In scan mode, operation of the equalization controller basically consists of:
(1) cycling through all “valid” combinations of output optical fibers and wavelengths, and reading the power estimate associated with each such valid combination; and (2) adjusting, as a function of the power estimates, the intensity control signals being fed to the VOICs.
[0146] A “valid” combination referred to in (1) above means that an optically carrier modulated data signal is expected to be found on that particular wavelength and on that particular output optical fiber.
[0147] Typically, at any given instant, many combinations of output optical fiber and wavelength will be valid but some will not, i.e., it is expected that one or more wavelengths on one or more output optical fibers may not contain an optical carrier modulated data signal. Whether or not a particular combination is valid depends on the connection map and thus will be known to the switch controller 160 ′. The switch controller 160 ′ can therefore make available a list of valid combinations to the equalization processor. This list is then kept up to date in a manner to be described further on when discussing the “directed mode” of operation.
[0148] Having determined that a particular combination of wavelength and output optical fiber is indeed valid, the equalization processor, still in step (1) of scan mode, must read the power estimate corresponding to this combination. The manner in which this is achieved depends on the configuration of the controller as a whole. For example, let the equalization processor be required to access the power estimate associated with the J th wavelength on the K th output optical fiber.
[0149] In the embodiment of FIG. 5 , the equalization processor 554 would obtain the desired power estimate by reading the output of power estimation module 530 J,K , which is uniquely associated with the desired combination of wavelength and output optical fiber.
[0150] In the embodiment of FIG. 6 , the equalization processor 654 sends a message to the filter driver 656 , which then instructs the K th wavelength-tunable optical bandpass filter 610 K to pass light occupying the J th wavelength. The equalization processor 654 would then obtain the desired power estimate by reading the output of the K th power estimation module 530 K .
[0151] In the embodiment of FIG. 7 , the equalization processor 754 sends a message to the switch driver 758 , which then instructs the optical switch matrix 710 to raise the K th mirror 712 K . The equalization processor 754 would then obtain the desired power estimate by reading the output of the J th power estimation module 530 j .
[0152] In the embodiment of FIG. 8 (with the coupler 810 in place), the equalization processor 854 sends a message to the switch driver 858 , which then instructs the switch matrix 710 to raise only the K th mirror and also instructs the appropriate one of the optical switch matrices 710 ′ to raise only the J th mirror. The equalization processor 854 would then obtain the desired power estimate by reading the output of the power estimation module 530 .
[0153] Finally, in the embodiment of FIG. 9 , the equalization processor 954 sends a first message to the switch driver 958 , which then instructs optical switch matrix 710 to raise the K th mirror 712 K . The equalization processor 954 also sends a second message to the filter driver 956 , which instructs the wavelength-tunable optical bandpass filter 610 to pass light occupying the J th wavelength. The equalization processor 954 would then obtain the desired power estimate by reading the output of the power estimation module 530 .
[0154] Now having regard to step (2) above, namely the adjustment of the intensity control signals being fed to the VOICs 410 as a function of the power estimates, the scan mode of operation provides for at least two ways of performing this step.
[0155] In a preferred version of step (2) in scan mode operation, the received power estimate associated with a valid combination (e.g., the J th wavelength on the K th output optical fiber) is immediately compared to a pre-determined reference value, and the resulting difference is encoded as an intensity control signal that is fed to the demultiplexer 558 . The demultiplexer 558 is then controlled to send this intensity control signal to the appropriate one of the latches 556 , which is then used to drive the appropriate VOIC via the appropriate intensity control line 415 J,K .
[0156] This procedure is repeated for each valid combination of wavelength and output optical fiber. After a finite time, the output power level of each carrier on each output optical fiber will converge to the respective desired output power level.
[0157] In an alternate version of step (2) in scan mode of operation, all the power estimates associated with valid wavelengths on the K th output optical fiber are read, following which a reference output power level for the carriers on the K th output optical fiber is computed.
[0158] Next, the difference between the reference output power level and the power estimate associated with a particular valid wavelength (e.g., the J th wavelength) on that K th output optical fiber is fed as an intensity control signal to the demultiplexer 558 . The demultiplexer 558 is then controlled to send this intensity control signal to the appropriate one of the latches 556 , which is used to drive the appropriate VOIC via the appropriate intensity control line 415 J,K .
[0159] This procedure is repeated for each output optical fiber (i.e., for each value of K). After a finite time, the output power level of each carrier on each output optical fiber (i.e., for each set of J and K corresponding to a valid combination) will have converged to the appropriate reference output power level.
[0160] It will be appreciated that either version of the scan mode of operation described above provides gain flattening which advantageously compensates for unequal and uncorrelated power levels among the carriers which would otherwise have occurred due to the arbitrary connection map applied by the photonic switch core 150 under control of the switch controller 160 ′.
[0161] Furthermore, it is noted that the optical power of each carrier is estimated only after the carrier has already exited the respective one of the WDM devices 130 A - 130 N , located at the output of the photonic switch 400 . Thus, the power equalization provided by the present invention is also capable of compensating for wavelength-dependent losses introduced by the WDM devices 130 A - 130 N as well as for and path-dependent losses through the photonic switch core 150 .
[0162] Moreover, because only N couplers 420 are required and because each such coupler is associated with only one of the output optical fibers 140 , another advantage of the invention is that the requirements on the tolerance of the couplers 420 need not be severe. This is due to the fact that variations in the flat loss between couplers causes a constant amplitude error across all wavelengths existing on a given fiber and therefore does not affect the spectral flatness. Moreover, such errors in the flat loss can be compensated for in the line system amplifiers 145 , if the couplers 420 are placed in front of the amplifiers 145 and if the amount of compensation is within the amplifiers' dynamic range.
[0163] Having described the scan mode of operation, the need for a directed mode of operation arises in the situation where the controller 160 ′ is ready to instruct the photonic switch core 150 to apply a new connection map. That is to say, a directed mode of operation is required when (I) one or more combinations which were previously not valid are now considered to be valid or (II) when valid connections are re-arranged. The reason for this is that suddenly adding new carriers or rearranging existing carriers can result in the disruption of those carriers which remain in service unchanged, due to the possibility of the new or rearranged optical carriers causing a sudden change in the optical amplifier gain or causing non-linear optical effects.
[0164] Accordingly, as shown in FIG. 10 , the directed mode of operation is entered when an INTERRUPT message 1010 is received by the equalization processor from the switch controller 160 ′. The INTERRUPT message 1010 is indicative of the fact that a new connection map is about to be established by the switch controller 160 ′. Specifically, the INTERRUPT message 1010 contains the identity of (A) all the combinations which are currently not valid but which will become valid as a result of the upcoming change to the connection map; (B) all the combinations which are currently valid but which will become invalid as a result of the upcoming change to the connection map; and (C) all the combinations which are currently valid and which are about to be rearranged.
[0165] Upon receipt of the INTERRUPT message 1010 , the equalization processor enters an initialization routine 1020 , whereupon the equalization processor proceeds to read the power estimate associated with: (i) each presently invalid but soon-to-be valid combination of wavelength and output optical fiber; and (ii) each presently valid and soon-to-be rearranged combination of wavelength and output optical fiber. The equalization processor then confirms that there is no carrier present on the combinations identified under (i) above. For the purposes of the reading the power estimate of a particular invalid but soon-to-be valid combination, it is understood that the respective intensity control signal should be set to a reasonable value (i.e., not to minimum gain/maximum attenuation).
[0166] Next, the equalization processor enters a neutralization routine 1030 . Specifically, for each combination under (i) and (ii) above, the respective intensity control signal is ramped down to a value which provides minimum gain (or maximum attenuation, as appropriate). Setting the intensity to minimum gain/maximum attenuation is done in order to prevent the onset of disruptions to other carriers on the same output optical fiber upon adding the new or rearranged carrier, while the ramping down process mitigates the onset of disruptions to these other carriers during execution of the neutralization routine 1030 itself.
[0167] After having completed the neutralization routine 1030 , the equalization processor sends a PROCEED message 1040 to the switch controller 160 ′, authorizing it to proceed with the establishment of the new connection map. In response to receipt of the PROCEED message 1040 , the switch controller 160 ′ applies the new connection map at step 1050 and sends an ACKNOWLEDGE message 1060 back to the equalization processor. The ACKNOWLEDGE message 1060 indicates that the new connection map has been established.
[0168] In response to receipt of the ACKNOWLEDGE message 1060 , the equalization processor proceeds to execution of a ramping routine 1070 . The ramping routine 1070 consists of increasing the power level of each carrier that was neutralized in the neutralization routine 1030 , i.e., each carrier associated with (a) each previously invalid but now valid combination of wavelength and output optical fiber; and (b) each previously valid and now rearranged combination of wavelength and output optical fiber. This increase in power level can be effected by increasing the value of the intensity control signal for each VOIC associated with a previously neutralized carrier from its minimum gain/maximum loss value (previously set in the neutralization routine 1030 ) to a value which brings the corresponding individual optical carrier signal to the same optical power level as the other individual optical carrier signals sharing the same output optical fiber.
[0169] As the value of the intensity control signal is being changed, the power estimates received from the power estimation module(s) will change and should therefore be given time to converge to new values. Hence, it is desirable to raise or lower the value of the appropriate intensity control signal in a gradual fashion, e.g., by ramping. The result of this ramping process will be to reduces the risk of affecting those wavelengths that already carry high speed optical data signals and that are not allowed to be disturbed.
[0170] Finally, before exiting the directed mode of operation, the equalization processor executes an update routine 1080 , which consists of updating its list of valid and invalid combinations, based on the information in the INTERRUPT message 1010 . (It is recalled that this list is consulted by the equalization processor while running in scan mode.) The equalization processor subsequently returns to scan mode.
[0171] Thus, through operation of the equalization processor in directed mode and interaction of the equalization processor with the switch controller 160 ′, the present invention achieves the advantage of reducing disruptions to existing carriers due to changes in the connection map involving the addition or rearranging of one or more carriers on one of more output optical fibers.
[0172] Those skilled in the art will appreciate that many other embodiments are within the scope of the invention. For instance, instead of gradually decreasing and then increasing the power of each new or rearranged carrier, such carriers could be removed or introduced in an incremental fashion, i.e., in groups of one or two, etc. Thus, the neutralization routine 1030 could be represented by a process in which one intensity control signal at a time (or two intensity control signals at a time, etc.) is gradually or suddenly decreased to a minimum gain/maximum attenuation value.
[0173] Similarly, the ramping routine 1070 could be replaced by a procedure whereby the affected carriers are introduced one by one without the need for ramping but with a suitable delay between the introduction of each new carrier in order to allow the power estimates to converge to new values. The gradual introduction of carriers still reduces the risk of causing a hit on those wavelengths which already carry high speed optical data signals and which should not be disturbed.
[0174] FIG. 12 shows another variant of the photonic switch 400 of FIG. 4 which provides “coarse” intensity control at the input to each WDD device in the photonic switch 400 . Specifically, a tap coupler (splitter) 1220 and a VOIC 1210 intercept each input optical fiber 120 , between the respective amplifier 125 and the respective one of the WDD devices 110 A - 110 N .
[0175] Each VOIC 1210 applies relatively flat gain or attenuation which affects all wavelengths on the given input optical fiber 120 to substantially the same degree. Thus, each VOIC 1210 should be capable of operating over a wider optical bandwidth than required for any of the VOICs 410 . The amount of attenuation or gain to be applied by each VOIC 1210 is encoded by a respective intensity control signal arriving along a respective intensity control line 1250 from a plurality of latches 1256 . The latches 1256 are driven by a demultiplexer 1258 that is fed by a co-processor 1254 .
[0176] In the coarse equalization scheme of FIG. 12 , the amount of gain or attenuation to be applied by each VOIC 1210 is controlled such that the aggregate optical power of the optical signal on each input optical fiber 120 is approximately the same before entering the respective one of the WDD devices 110 A - 110 N . In order to measure this aggregate optical power, each tap coupler 1220 is connected by a respective optical path 1240 to a respective input of a common N-input optical switch matrix 1230 .
[0177] The optical switch matrix 1230 can be identical to the switch matrices 710 , 710 ′ described with respect to FIGS. 7-9 . It consists of a plurality of mirrors which can be controllably raised or lowered in order to let through the optical signal present on a selected one of the optical paths 1240 . Control of the raising and lowering of mirrors in the optical switch matrix 1230 is achieved by the co-processor 1254 via an intervening switch driver 1235 .
[0178] An output of the optical switch matrix 1230 is connected to an optical receiver 1260 , which comprises circuitry such as a photodiode and a trans-impedance amplifier for converting into electrical form the optical signal present at its input. In the embodiment of FIG. 12 , the signal received at the input to the optical receiver 1260 occupies multiple wavelengths and therefore the optical receiver 1260 must have a wide optical bandwidth of operation.
[0179] The output of the optical receiver 1260 is connected to a power estimation module 1270 which can be identical to any of the power estimation modules 530 suitable for use with the embodiments of FIGS. 5 through 9 . The output of the power estimation module 1270 is fed to the co-processor 1254 .
[0180] In operation, the co-processor 1254 (which can function independently of any of the processors 554 , 654 , 754 , 854 , 954 or can be integrated therewith) controls the raising and lowering of the mirrors in the optical switch matrix 1230 via the switch driver 1235 in order to obtain an aggregate power estimate, one input optical signal at a time, from the power estimation module 1270 . The co-processor 1254 then compares each received power estimate to a reference and the difference is applied to the appropriate VOIC 1210 through control of the demultiplexer 1258 and the appropriate one of the latches 1256 .
[0181] Thus, the co-processor 1254 strives to maintain all the aggregate input power levels at substantially the same value in a feed-forward fashion. In general, this coarse power level adjustment will produce a significant reduction in the spread among optical power levels on a particular output optical fiber 140 , with the consequence that the dynamic range of the VOICs 410 (which are controlled by processor 554 , 654 , 754 , 854 or 954 ) can be significantly reduced. This reduction in required dynamic range allows the use of less expensive VOICs 410 in each switched demuxed optical path 180 .
[0182] It is also within the scope of the invention to provide coarse power equalization at the input end in the manner of a true feedback loop as shown in FIG. 12A . For improved performance, the order of the tap couplers 1220 and the VOICs 1210 along each input of the optical fibers 120 can be reversed as shown. Greater disparities in the loss of the various VOICs 1210 can then be tolerated due to the power level measurements having been obtained via the tap couplers 1220 following (rather than before) application of intensity control by the VOICs 1210 . When designing the feedback loop, however, those skilled in the art will of course recognize that special attention must be paid to stability concerns.
[0183] Those skilled in the art will also appreciate that in FIGS. 12 and 12A , the optical switch matrix 1230 and its associated switch driver 1235 can be omitted without affecting the way in which the coarse equalization scheme works. Specifically, it is within the scope of the invention to provide separate sets of optical receivers 1260 and power estimation modules 1270 in each optical path 1240 . Any individual power estimate could then be accessed by the co-processor 1254 via a common intervening multiplexer (not shown).
[0184] Other coarse equalization schemes can be implemented. For example, the couplers 1220 , the optical switch matrix 1230 , the switch driver 1235 , the optical receiver 1260 and the power estimation module 1270 can be dispensed with while still providing coarse equalization at the input through the action of the VOICs 1210 . Such an embodiment is shown in FIG. 13 , where the co-processor ( 1254 in FIG. 12 ) and processor ( 554 , 654 , 754 , 854 , 954 in FIGS. 5-9 ) have been integrated into a single equalization processor 1354 in the equalizer 500 ′. As a result of the radical hardware simplification of the embodiment of FIG. 13 with respect to the embodiment of FIG. 12 , the algorithm being run by the equalization processor 1354 is slightly more complex.
[0185] Specifically, the equalization processor 1354 operates in scan mode until it is interrupted by the switch controller 160 ′, whereupon the equalization processor 1354 enters a directed mode of operation.
[0186] The actions performed by the equalization processor 1354 in directed mode, in respect of preparing for the appearance of a new or re-arranged carrier, remain unchanged from those described previously. However, it is the equalization processor's routine operation in scan mode which is slightly more complex because the equalization processor 1354 controls the amount of intensity variation applied by not one but both sets of VOICs 1210 and 410 . Specifically, in each pass through the algorithm in scan mode, the equalization processor 1354 does not compute the “fine” gain or attenuation to be applied by the VOICs 410 until it has computed the “coarse” gain or attenuation to be applied by the VOICs 1210 .
[0187] Since the power estimates available to the equalization processor 1354 are typically post-switching power estimates, and since the coarse intensity control is performed by the VOICs 1210 prior to switching, the controller 1354 must invert the connection map applied by the controller 160 ′ in order to determine the amount of coarse intensity control it should apply at the input in order to result in a reduction in the power spread on each output optical fiber 140 . Different ways of inverting a connection map will be known to those skilled in the art.
[0188] Practically, the equalization processor first determines the required gain for each individual demuxed switched optical path in the already described manner, and then determines how much of this gain or attenuation is common to all paths originating from the same input optical fiber. The common amount of intensity control is applied to the appropriate one of the VOICs 1210 and the remaining amount of intensity control for each demuxed switched optical path is applied to the appropriate VOIC 410 .
[0189] In this way, the dynamic range required to be handled by the VOICs 410 can be significantly reduced, because each VOIC will only have to supply a residual amount of gain or attenuation. Thus, the hardware requirements are reduced with respect to the embodiment of FIG. 12 , at the expense of a slight increase in computational complexity with respect to the controller 1254 .
[0190] Of course, a similar coarse equalization scheme can be applied at the output of the WDM devices 130 A - 130 N , prior to tapping by the couplers 420 . This embodiment is shown in FIG. 14 , where each of the output optical fibers 140 is intercepted by a respective one of a plurality of VOICs 1410 A - 1410 N placed between a respective one of the WDM devices 130 A - 130 N and the respective coupler 420 .
[0191] In the case of FIG. 14 , each of the VOICs 1410 A - 1410 N applies a coarse amount of intensity control to all the wavelengths of the associated output optical fiber 140 . Hence, the equalization processor 1454 in the equalizer 500 ″ would determine the amount of required intensity control which is common to all wavelengths sharing an output optical fiber, would apply the common amount of intensity control to the appropriate one of the VOICs 1410 A - 1410 N and would apply the amount of residual gain or attenuation to the appropriate VOICs 410 .
[0192] Again, the dynamic range required to be handled by the VOICs 410 can be significantly reduced, because each will only have to supply a residual amount of gain or attenuation. This can significantly reduce the aggregate cost of the VOICs 410 , at the expense of a slight increase in computational complexity with respect to the equalization processor 1454 in the equalizer 500 ″. In fact, this embodiment is even simpler than the embodiment of FIG. 12 or FIG. 13 because it does not require knowledge of the connection map through the photonic switch core 150 .
[0193] Further modifications and refinements of the above-described embodiments are within the scope of the invention. In particular, it is recalled that the embodiments of FIGS. 5 , 7 and 8 employ WDD devices 510 within the equalizer 500 and the embodiments of FIGS. 7 , 8 and 9 use one or more optical switch matrices 710 , 710 ′. Due to the wavelength-dependent loss characteristics of the WDD devices 510 and due to path-dependent loss characteristics of the optical switch matrices 710 , 710 ′, it should be apparent that power level variations may be introduced by these components, depending on the specific path taken by light travelling from the couplers 420 to the equalization controller 500 . Hence, losses inherent to the measurement process itself may distort the power estimates produced by the power estimation module(s) 530 .
[0194] A solution to this problem is provided in FIG. 15 , which illustrates an equalizer 1500 with a front end 1502 , an optical receiver bank 1504 , a power estimation module bank 1506 and an equalization controller 1510 which collectively encompass the embodiments previously described with reference to FIGS. 5 through 9 . Additionally, the equalizer 1500 is equipped with calibration functionality. Specifically, in order to enable the computation of the loss of each possible path from the output optical fibers 140 to the equalization controller 1510 , there is provided a calibration source 1520 for providing light of a desired wavelength and at a desired gain. The calibration source 1520 is fed by the equalization processor 1554 in the equalization controller 1510 .
[0195] At the output of the calibration source 1520 is provided an (N+1)-way splitter 1530 , which sends the incoming light from the calibration source 1520 along N+1 different optical fibers 1540 A - 1540 N , 1550 . Optical fibers 1540 A - 1540 N are coupled via a respective plurality of couplers 1560 A - 1560 N to the N optical paths 425 A - 425 N leading from the couplers 420 . Optical fiber 1550 leads directly to the controller 1510 via an attenuator 1570 , an optical receiver 1580 and a power estimation module 1590 . The attenuator 1570 provides a fixed attenuation to account for the loss through the (N+1)-way splitter 1530 .
[0196] In operation, the equalization processor 1554 operates in scan mode until the switch controller 160 ′ indicates that it is about to change the connection map through the photonic switch core 150 . Operation of the equalization processor 1554 in scan mode is virtually the same as previously described with reference to FIGS. 5 through 9 , with one main variation.
[0197] Specifically, after evaluating the difference between a desired power level and the estimated power of a signal associated with a particular combination of wavelength and output optical fiber, the equalization controller 1510 adjusts this difference by a “calibration factor” associated with the path of that signal from the associated one of the couplers 1560 A - 1560 N to the equalization controller 1510 through the front end 1502 .
[0198] The “calibration factor” associated with a path represents the inverse of the relative loss of that path. One way in which the equalization processor 1554 may determine the calibration factor of a particular path through the front end 1502 is as follows:
select a wavelength; instruct the calibration source 1520 to emit at that wavelength; instruct the front end 1502 to pass through the desired wavelength along the desired path; read from the power estimation module bank 1506 the power estimate corresponding to the desired wavelength arriving along the desired path; read the power estimate received from the power estimation module 1590 ; determine the difference between the two values and store the result as the calibration factor for that particular path.
[0205] The calibration factor of each path is not expected to change with time, since the properties of the components located between the couplers 1560 A - 1560 N are not expected to change. Thus, the calibration step can be performed during an initialization phase. Still, in order to apply the appropriate calibration factor, it is necessary for the equalization processor 1554 to maintain an updated mapping of which combination of output optical fiber and wavelength is associated with which path.
[0206] By adjusting the intensity control signals provided to the VOICs 420 by the above-introduced calibration factors, the present invention as embodied in FIG. 15 advantageously compensates for errors which may otherwise have been introduced by the measurement process. Of course, it should be understood that the calibration is accurate to the degree that the properties of the optical receiver 1580 and power estimation module 1590 approximate those of the components in the optical receiver bank 1504 and the power estimation module bank 1506 .
[0207] It should be appreciated that the calibration scheme of FIG. 15 can also be used in order to calibrate individual optical paths through either of the coarse equalization schemes previously described with reference to FIG. 12 or 12 A. The application of the calibration scheme of FIG. 15 to the coarse equalization scheme of FIG. 12A is shown in FIG. 16 , where the couplers 1560 A - 1560 N are connected to the optical paths 1240 leading from the tap couplers 1220 connected to the input optical fibers 120 . It is noted that the calibration source 1620 is a multi-colored light source which spans the same optical frequency range as any of the input WDM signals on the input optical fibers 120 .
[0208] The co-processor 1654 operates as previously described with reference to FIG. 12 . However, after evaluating the difference between a desired power level and the estimated power of an input WDM signal associated with a particular input optical fiber, the co-processor 1654 adjusts this difference by a “calibration factor” associated with that input optical fiber. This “calibration factor” represents the inverse of the relative loss of the path travelled by light coming from that input optical fiber through the associated one of the couplers 1560 A - 1560 N and through the optical switch matrix 1230 .
[0209] One way in which the co-processor 1654 may determine the calibration factor of a particular path through the optical switch matrix 1230 is as follows:
select an input optical fiber; instruct the calibration source 1620 to emit multi-colored light; instruct the optical switch matrix 1230 to pass through any light along the selected input optical fiber; read from the power estimation module 1270 the power estimate corresponding to the selected input optical fiber; read the power estimate received from the power estimation module 1590 ; determine the difference between the two values and store the result as the calibration factor for that particular input optical fiber.
[0216] The calibration factor associated with each input optical fiber is not expected to change with time, since the properties of the components located between the couplers 1560 A - 1560 N are not expected to change. Thus, the calibration step can be performed during an initialization phase.
[0217] It is seen that by adjusting the intensity control signals provided to the VOICs 1210 by these calibration factors, the present invention as embodied in FIG. 16 advantageously compensates for errors which may otherwise have been introduced during measurement of the intensity of each input WDM signal.
[0218] A further variation of the present invention involves placing the VOICs 410 at the input (rather than at the output) of the photonic switch core 150 . Knowledge of the connection map would then be required in order to determine which of the switched individual optical carrier signals are combined by which WDM devices 130 A - 130 N . Also, it may be desirable in such a scenario to account for the dB loss of each signal through the photonic switch core 150 , which loss would be constant so long as the connection map remains constant and would change as the connection map changes. Since this change is usually predictable to a good degree of accuracy, the equalization processor can adjust the intensity control signal supplied to each of the VOICs 410 by the respective known loss through the switch core 150 .
[0219] In other embodiments of the invention, the output of the optical receivers 520 could be connected to functional units other than a power equalization system, such as a path integrity analyzer described in the co-pending U.S. patent application to Graves et al., entitled “Optical Switch with Connection Verification” and filed on even date. Of course, this assumes that the optical receivers 520 have sufficient electrical bandwidth to meet the functional requirements of the path integrity analyzer.
[0220] While specific embodiments of the present invention have been described and illustrated, it will be apparent to those skilled in the art that still further modifications and variations can be made without departing from the scope of the invention as defined in the appended claims. | An optical intensity control system for use with an optical switch providing individual signal paths between input and output ports. The system has optical splitters connectable to output multiplexers of the switch and has variable optical intensity controllers (VOICs) for insertion into the individual signal paths to individually control the intensity of optical signals present in the signal paths via intensity control signals. An equalizer connected to the splitters and the VOICs produces an estimate of the optical power of each individual switched optical signal and generates the intensity control signals. The equalizer is adapted to controllably isolate individual switched optical signals. In this way, individual and independent control of the power on each optical channel is provided. | 7 |
FIELD OF THE INVENTION
[0001] The field of the invention relates to pharmaceutically applicable compounds and polymorphs being classed among the ziprasidone hydrobromide compound group known to have strong antipsychotic effect. Ziprasidone is an antipsychotic agent that is chemically 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one of Formula I.
[0000]
[0002] The field of the invention relates to new ziprasidone-hydrobromide compounds: ziprasidone-hydrobromide monohydrate, crystalline and amorphous ziprasidone-hydrobromide, ziprasidone-hydrobromide hemihydrate, ziprasidone-sesquihydrobromide hemiformiate.
[0003] The field of the invention also relates to five ziprasidone-hydrobromide polymorph forms pertaining to the ziprasidone hydrobromide group, Ziprasidone-hydrobromide Form I-V, and preparation processes thereof:
The field of the invention relates to Ziprasidone-hydrobromide Form I which is a crystalline modification of ziprasidone-hydrobromide monohydrate of Formula II. The field of the invention also relates to Ziprasidone-hydrobromide Form II which is a crystalline modification of ziprasidone-hydrobromide anhydrate of Formula III. The field of the invention also relates to Ziprasidone-hydrobromide Form III which is a crystalline modification of ziprasidone-hydrobromide hemihydrate of Formula IV. The field of the invention also relates to Ziprasidone-hydrobromide Form IV which is a crystalline modification of ziprasidone-sesquihydrobromide hemiformiate of Formula V. The field of the invention also relates to Ziprasidone-hydrobromide Form V which is amorphous modification of ziprasidone-hydrobromide of Formula III.
[0000]
[0000] The field of the invention also relates to some economical preparation methods that are suitable for industrial production of high purity ziprasidone hydrobromide modifications. In a generally applicable method ziprasidone base is dissolved in formic acid, aqueous or non-aqueous hydrogen bromide is added, and the product is precipitated with the aid of an antisolvent. The circumstances of this general process determine which Form is prepared.
BACKGROUND OF THE INVENTION
[0009] Ziprasidone, 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one of Formula I and pharmaceutically acceptable salts thereof are disclosed in U.S. Pat. No. 4,831,031 (European equivalent: EP 0 281 309) and are known as neuroleptic active ingredients. Furthermore, it is known from U.S. Pat. No. 6,245,766 that these actives have excellent efficacy for the treatment of psychiatric states and disorders arising from demencia, among others Alzheimer-type demencia, and bipolar disorders. There are no data in the literature referring to that ziprasidone hydrobromide really has been prepared. Although, in the PCT Publication No. WO 2006/034965 there is an indirect remark on the existence of—among others—hydrobromide addition salt, but there are not data on its preparation, or physical, chemical characteristics. According to this description the addition salts can be discomposed by hydrogen chloride, hydrogen bromide, methanesulphonic acid, preferably by hydrogen chloride, and in the latter case especially pure ziprasidone hydrochloride can be obtained. In the description there are examples for ziprasidone maleate, ziprasidone acetate, and ziprasidone hydrochloride anhydrate, however there is no example on the ziprasidone hydrobromide salt group.
[0010] As ziprasidone hydrobromide preparation methods have not been published in the literature, the ziprasidone hydrochloride preparation methods are taken as the technical anteriority as follows:
[0011] According to Example 16 of U.S. Pat. No. 4,831,031 ziprasidone hydrochloride is obtained if 5-(2-chloroethyl)-6-chloro-1,3-dihydro-2H-indol-2-one is reacted with 3-piperazinyl-1,2-benzisothiazol hydrochloride in the presence of sodium-carbonate and sodium-iodide in methyl isobutyl ketone boiling the mixture for 40 hours. Then the reaction mixture is filtered, evaporated, and the residue is purified with chromatography. The evaporated residue of chromatography is dissolved in dichloromethane, and after acidification by hydrochloric acidic diethyl ether, the precipitated crystals are filtered out, washed with ether and acetone.
[0012] The obtained product is declared as 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one hydrochloride hemi hydrate (ziprasidone hydrochloride hemihydrate).
[0013] This method is unusable for industrial production, however according to the procedure of European Patent No. EP 584 903 ziprasidone hydrochloride can be prepared at a high yield (80%) even in an industrial scale. In this procedure also the same components: 5-(2-chloroethyl)-6-chloro-1,3-dihydro-2H-indol-2-one and the hydrochloride salt of 3-piperazinyl-1,2-benzisothiazol are reacted with each other in the presence of sodium-carbonate, but in this case the solvent is simply water. Here the isolation is followed by a complicated clearing step.
[0014] European Patent No. EP 586 191 reveals a method according to which ziprasidone hydrochloride monohydrate is obtained in a reaction of the clean ziprasidone base with diluted aqueous hydrochloric acid solution.
[0015] The PCT Publication No. WO 2005/061493 reveals a preparation method of ziprasidone hydrochloride anhydrate. However, having reproduced this and similar other methods—for preparation ziprasidone hydrochloride anhydrate that would be stable in normal air conditions—only the unsuitability for industrial-scale application has been proved. Ziprasidone hydro-chloride anhydrate samples adsorbed water rapidly from air even if prepared in rigorously anhydrous circumstances.
[0016] These observations are in accordance with data of EP 586 191 (equivalent U.S. Pat. No. 5,338,846): that ziprasidone hydrochloride anhydrate (water content: 0.19%) can be prepared from ziprasidone hydrochloride monohydrate (water content: 3.9%) with drying for 28.5 hours (instead of 7 hours) at a temperature of 40-50° C. This application describes that ziprasidone hydrochloride anhydrate binds water depending on the relative humidity of air. For example at 31% relative humidity the water content of the product increased to 2.55% after 4 hours.
[0017] As in the practice only the monohydrate salt of the ziprasidone hydrochloride is relatively stable, and even the monohydrate can loose water, during the drying procedure generally a mixture of ziprasidone hydrochloride monohydrate and anhydrate is resulted. It is known that such a mixture does not provide an optimal base for a validated industrial production.
[0018] The occurrence of different crystal forms possesses different solid state properties, can have various stability, mechanical, physical properties like melting point, spectroscopic behaviours, their crystal habits and thermodynamic properties are different. These properties influence the applicability of the active ingredients for formulation purposes. Another important solid state feature is the solubility entailing therapeutic consequences. The discovery of new polymorphic forms of a pharmaceutically useful compound provides a new opportunity to improve the performance characteristics of a pharmaceutical product. It enlarges the repertoire of active materials for the formulation purposes. There is a need in the art for additional polymorphic forms of ziprasidone salts.
SUMMARY OF THE INVENTION
[0019] The present invention provides pharmaceutically applicable compounds and polymorphs belonging to the ziprasidone hydrobromide compound group with antipsychotic effect. The present invention provides hydrobromide polymorphs of 5-{2-[4-(1,2-benzisothiazol-3-yl) -1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one, ziprasidone of Formula I having neuroleptic activity.
[0000]
[0000] The invention discloses new ziprasidone hydrobromide compounds; ziprasidone hydrobromide monohydrate, crystalline and amorphous ziprasidone hydrobromide anhydrate, ziprasidone hydrobromide hemihydrate and ziprasidone sesquihydrobromide hemiformiate. The invention discloses the new polymorph modifications being classed among the ziprasidone hydrobromide compound group (Ziprasidone-hydrobromide Form I-V) and preparation methods thereof.
[0020] The new polymorphs show good stability, provide advantages in formulation, and with increasing diversity and choice range provide new possibilities to fulfill the demands of formulation and biological utilization.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Regarding the foregoing problems, the present invention has proceeded with extensive research.
[0022] During our experimental work we prepared different ziprasidone hydrobromide compounds and forms. It was found surprisingly that the stability of ziprasidone hydrobromide salt forms is regularly better than that of the similar ziprasidone hydrochloride forms. In suitable circumstances both the anhydrate and the monohydrate of ziprasidone hydrobromide can be prepared in stable forms, at normal humidity these products can easily be handled, meanwhile their water and active ingredient contents remain constant. The hemihydrate of ziprasidone hydrobromide can also be prepared reproducibly.
[0023] According to thermogravimetric (TG) and differential scanning calorimetric (DSC) investigations, during heating Ziprasidone-hydrobromide Form I (a ziprasidone hydrobromide monohydrate) loses water between 40-60° C., however after the heat-effect it readily takes back the water, and transforms back to monohydrate of the original crystal structure. If a Ziprasidone-hydrobromide Form I (monohydrate) sample or a Ziprasidone-hydrobromide Form II (anhydrate) sample is taken into a 100% relative humidity area at room temperature, their water content does not change significantly. The Ziprasidone-hydrobromide Form III (hemihydrate) sample was also stable in these circumstances.
[0024] Having revealed the advantageous characters of these modifications, we discovered further modifications of the ziprasidone-hydrobromide family. The new polymorph forms can provide new possibilities to enhance the performance characteristics of a pharmaceutical product. The up-to-date formulation technology requires the availability of the new polymorphs of the active ingredients. During our experiments we produced reproducibly Ziprasidone-hydrobromide Form IV (a ziprasidone sesquihydrobromide hemiformiate) and Ziprasidone-hydrobromide Form V (an amorphous modification of ziprasidone hydrobromide).
[0025] Our experiments proved that both ziprasidone hydrobromide monohydrate and ziprasidone hydrobromide anhydrate can be produced equally starting from homogeneous or heterogeneous reaction mixtures. According to a pharmaceutically advantageous solution ziprasidone base solution is reacted by aqueous or acetic acidic hydrogen bromide in such circumstances that promote the precipitation of the solid form. For the preparation of these polymorphs and for the dissolution of the ziprasidone base, formic acid is especially appropriate, however, the acetic acid (and the solutions of acetic acid in methanol, ethanol, tetrahydrofuran or ethyl acetate) can be utilized favorably, as well. For heterogeneous phase production a suspension can be formed using simple alcohols, advantageously with methanol or ethanol, with tetrahydrofuran or water, or other solvents containing tetrahydrofuran or water, more advantageously water.
[0026] The hydrogen bromide solution may be diluted favorably with water, acetic acid, alcohols, ethyl acetate, tetrahydrofuran, methyl isobuthyl keton.
[0027] Ziprasidone-hydrobromide Form I (ziprasidone hydrobromide monohydrate) can be prepared advantageously if a solution of ziprasidone base in a solvent of formic acid, acetic acid or including thereof is reacted with aqueous hydrogen bromide solution. The reaction is carried out advantageously at a room temperature or with a relatively short boiling, preferably for 0.5-3 hours. Then the mixture is cooled back to room temperature, after crystallisation the solid is filtered out, and dried. This product can be prepared from a suspension of ziprasidone base, as well, if a suspension, advantageously an alcoholic aqueous suspension of ziprasidone base is boiled for 0.5-3 hours. Then the mixture is cooled back to room temperature, the solid is filtered out, and dried. The product can also be produced in a similar manner if instead of ziprasidone base another ziprasidone hydrobromide salt is used, but in this case the hydrogen bromide is left out.
[0028] Ziprasidone-hydrobromide Form II (generally ziprasidone hydrobromide anhydrate) can be prepared advantageously, according to one aspect of the present invention, if an anhydrous solution, advantageously anhydrous formic acidic solution, of ziprasidone base is reacted with anhydrous hydrogen bromide solution, advantageously in anhydrous methanolic-glacial acetic acidic solution. The reaction is carried out advantageously at room temperature. After crystallization the solid is filtered out, and dried. According to another aspect of the present invention ziprasidone hydrobromide anhydrate can be prepared starting from an aqueous media if the water is removed from the reaction mixture in a long-lasting, advantageously in 8-20 hour's boiling. In these cases the ziprasidone base advantageously can be dissolved in formic or acetic acid, or in a solution including formic or acetic acid with methanol, ethanol, tetrahydrofuran or ethyl acetate. The reaction can be carried out in heterogeneous phases, as well. For this purpose suitable suspensions can be made with simple alcohols, advantageously with methanol or ethanol, or including thereof with other solvents, advantageously with methanol and tetrahydrofuran. The product can also be produced in a similar manner if instead of ziprasidone base another ziprasidone hydrobromide salt is used, but in this case the hydrogen bromide is left out. Ziprasidone-hydrobromide Form II can be especially advantageously produced from Ziprasidone-hydrobromide Form IV (generally ziprasidone sesquihydrobromide hemiformiate) with a short heating at a temperature between 180-200° C.
[0029] Ziprasidone-hydrobromide Form III (generally ziprasidone hydrobromide hemihydrate) can be prepared advantageously, according to one aspect of the present invention, if an anhydrous solution, advantageously anhydrous formic acidic solution, of ziprasidone base is reacted with anhydrous hydrogen bromide solution, advantageously in anhydrous methanolic-glacial acetic acidic solution. According to another aspect of the present invention ziprasidone hydrobromide hemihydrate can from Ziprasidone-hydrobromide Form I if the formic acidic solution of the latter in a very short time, advantageously in 1 min. is added to water of 5-10° C. temperature. Then the solid is filtered out immediately, and dried.
[0030] Ziprasidone-hydrobromide Form IV (generally ziprasidone sesquihydrobromide hemiformiate) can be prepared advantageously, according to one aspect of the present invention, if an aqueous hydrogen bromide solution containing other solvents, advantageously methyl isobutyl ketone, ethyl acetate or tetrahydrofuran is added in a relatively short time, advantageously in 15 min. into a formic acidic solution of ziprasidone base. Then the solid is filtered out, and dried.
[0031] Ziprasidone-hydrobromide Form V (generally amorphous ziprasidone hydrobromide) can be prepared advantageously, according to one aspect of the present invention, if a hydrogen bromide solution in glacial acetic acid containing methyl isobutyl ketone is added in very short time, advantageously in 1 min. into a formic acidic solution of ziprasidone base at 65-70° C., followed by a 16 hour's after-stirring, then the solid is filtered out, and dried.
[0032] In similar manners in different solvents other solvates and amorphous forms of ziprasidone hydrobromide can also be prepared.
[0033] From the compounds and polymorphs described above orally, rectally or parentally usable pharmaceutical forms, as tablets, capsules, aqueous and oily suspension or dispergable powder forms can be made with generally used non-toxic, pharmaceutically suitable diluting, carrier, binding, disperging or other auxiliary materials.
[0034] Recently polymorphism has become one of the most important fields of the pharmaceutical industry since it concerns almost all characteristics of the solid active ingredient, sometimes in a dramatic extent. For discovery, identification, and differentiation of the new ziprasidone hydrobromide polymorphs a lot of solid analytical and other instrumental investigation methods were used together in a complex way.
[0035] In our solid analytical methods the following instrumental circumstances were applied.
[0036] FT-IR Spectrophotometry Parameters:
[0000]
Instrument:
Thermo-Nicolet 6700
Phase (solvent):
KBr
Resolution:
4 cm −1
Scan number:
100
[0037] The baselines of the spectra were normalized to absorbance of 1.0. Regarding the resolution of 4 cm −1 , the variance of the wavenumber values is not more than ±4 cm −1 .
[0038] Powder X-ray Diffraction Parameters:
[0000]
Instrument:
PANanalytical X'Pert PRO
Radiation:
CuK α
Accelerating voltage:
40 kV
Anode current:
40 mA
Goniometer:
PW3050/60
Recording speed:
0.208°2θ/s
Sample holder:
Spinner PW3064
Revolving speed:
1 s −1
Variance of 2θ:
±0.2°
[0039] Thermogravimetry (TG) Parameters:
[0000]
Instrument:
TA Instruments TGA Q50
Heating rate:
10° C./min
Sample size:
~10 mg
Atmosphere:
60 ml/min Na
[0040] Differential Scanning Calorimetry (DSC) Parameters:
[0000]
Instrument:
TA Instruments DSC Q10
Heating rate:
10° C./min
Sample size:
~1.5-2.5 mg
Type of skillet:
opened
Atmosphere:
50 ml/min N 2
LIST OF FIGURES
[0041] FIG. 1 : FT_IR spectrum of Ziprasidone-hydrobromide Form I
[0042] FIG. 2 : FT_IR spectrum of Ziprasidone-hydrobromide Form II
[0043] FIG. 3 : FT_IR spectrum of Ziprasidone-hydrobromide Form III
[0044] FIG. 4 : FT_IR spectrum of Ziprasidone-hydrobromide Form IV
[0045] FIG. 5 : FT_IR spectrum of Ziprasidone-hydrobromide Form V
[0046] FIG. 6 : Powder X-ray diffraction diagram of Ziprasidone-hydrobromide Form I
[0047] FIG. 7 : Powder X-ray diffraction diagram of Ziprasidone-hydrobromide Form II
[0048] FIG. 8 : Powder X-ray diffraction diagram of Ziprasidone-hydrobromide Form III
[0049] FIG. 9 : Powder X-ray diffraction diagram of Ziprasidone-hydrobromide Form IV
[0050] FIG. 10 : Powder X-ray diffraction diagram of Ziprasidone-hydrobromide Form V
EXAMPLES
[0051] The present invention is illustrated by the following examples without limiting the scope.
[0052] The water contents were determined with Karl Fischer titrimetric and/or thermogravimetric method. The HBr and formic acid contents were determined by titrimetry, and with the aid of a 13 C-NMR method, respectively.
Example 1
Preparation of Ziprasidone-hydrobromide Form I
[0053] 12,0 g 5-{2-[4-(1,2-benzisothiazol-3-yl) -1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in 48.0 ml formic acid at room temperature. The homogeneous solution was stirred with 0.6 g charcoal and 0.6 g silica gel 60 (particle size 0.040-0.063 mm) for 30 min, then it was filtered. The clear filtered solution was added into a mixture of 6.0 ml aqueous 48% (w/v) hydrogen bromide solution and 100 ml distilled water at 25-30° C. temperature, followed by an hour's after-stirring. Then the solid was filtered out, washed first with a mixture of 6.0 ml formic acid and 6.0 ml distilled water and then with 10.0 ml tetrahydrofuran, and dried at a reduced pressure of 4-6 kPa for 4 hour. 13.8 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide monohydrate (ziprasidone-hydrobromide monohydrate) in a form of Ziprasidone-hydrobromide Form I was obtained.
[0054] Powder X-ray diffraction diagram of the product is shown in FIG. 6 , the characteristic 2θ values are: 10.834, 15.746, 17.486, 19.138, 20.383, 24.906 and 25.673 [°]. The water content determined by titrimetry with Karl Fischer method: 3.72%.
Example 2
Preparation of Ziprasidone-hydrobromide Form I
[0055] 3.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1 -piperazinyl]-ethyl}-6-chloro-1,3 -dihydro-2H-indol-2-one (ziprasidone base) was dissolved in 12.0 ml formic acid at room temperature. The homogeneous solution was stirred with 0.2 g charcoal and 0.2 g silica gel 60 (particle size 0.040-0.063 mm) for 30 min, then it was filtered. The clear filtered solution was added dropvise, with stirring, in one hour into a mixture of 3.0 ml aqueous 48% (w/v) hydrogen bromide solution and 27.0 ml isopropanol at 25-30° C. temperature, followed by 1 hour's after-stirring. Then the solid was filtered out, washed first with a mixture of 3.0 ml formic acid and 3.0 ml isopropanol and then with 3.0 ml isopropanol, and dried at a reduced pressure of 4-6 kPa for 4 hour.
[0056] 3.32 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide monohydrate (ziprasidone-hydrobromide monohydrate) in a form of Ziprasidone-hydrobromide Form I was obtained.
[0057] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 1.
Example 3
Preparation of Ziprasidone-hydrobromide Form I
[0058] 4.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in boiling mixture of 4.0 ml distilled water and 56.0 ml tetrahydrofuran. The homogeneous solution was stirred with 0.2 g charcoal and 0.2 g silica gel 60 (particle size 0.040-0.063 mm) for 5 min, then it was filtered. 2.0 ml aqueous 48% (w/v) hydrogen bromide solution was added dropvise into the clear filtered solution at a temperature of 60-65° C., followed by an hour's after-stirring. Then the solid was filtered out, washed with 3.0 ml tetrahydrofuran, and dried at a reduced pressure of 4-6 kPa for 4 hour.
[0059] 3.68 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide monohydrate (ziprasidone-hydrobromide monohydrate) in a form of Ziprasidone-hydrobromide Form I was obtained.
[0060] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 1. Water content determined by Karl Fischer method: 3.49%.
Example 4
Preparation of Ziprasidone-hydrobromide Form I
[0061] 25.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was suspended at room temperature in a mixture of 12.5 ml distilled water and 112.5 ml ethanol, and then 8.2 ml 48% (w/v) hydrogen bromide solution was added. The suspension was boiled for 2 hours, and then it was cooled to room temperature, filtered, washed twice with 20.0 ml portions of ethanol, and dried under an infrared lamp.
[0062] 30.1 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide monohydrate (ziprasidone-hydrobromide monohydrate) in a form of Ziprasidone-hydrobromide Form I was obtained. Water content determined by Karl Fischer method: 3.60%.
[0063] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 1.
Example 5
Preparation of Ziprasidone-hydrobromide Form I
[0064] 3.0 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one hydrobromide anhydrate (ziprasidone hydrobromide anhydrate) in form of Ziprasidone-hydrobromide Form II was dissolved in 12.0 ml formic acid at a temperature of 75-80° C. 36.0 ml distilled water was added dropvise into the homogeneous solution, with stirring, in 30 min, followed by 1 hour's after-stirring. Then the solid was filtered out, washed with a mixture of 3.0 ml distilled water and 3.0 ml methanol, and dried at a reduced pressure of 4-6 kPa for 4 hour.
[0065] 2.89 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl }-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide monohydrate (ziprasidone-hydrobromide monohydrate) in a form of Ziprasidone-hydrobromide Form I was obtained.
[0066] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 1.
Example 6
Preparation of Ziprasidone-hydrobromide Form II
[0067] 20.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in a mixture of 50.0 ml dimethylacetamid and 100.0 ml methanol at room temperature, and 20.0 ml aqueous 48% (w/v) hydrogen bromide was added into it. The formed suspension was boiled for 16 hour, and then was cooled back to room temperature. The solid was filtered out, washed with methanol, and dried under infrared lamp.
[0068] 23.2 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in a form of Ziprasidone-hydrobromide Form II was obtained.
[0069] The FT-IR spectrum of the product is shown in FIG. 2 . The characteristic bands are at: 3224, 2582, 1708, 1628, 1486, 973 and 905 cm −1 values.
[0070] Powder X-ray diffraction diagram of the product is shown in FIG. 7 , according to it the characteristic 20 values are: 7.014, 11.081, 17.759, 19.339, 23.283, 26.094 and 29.498 [°].
[0071] During the thermogravimetric investigation with heating up to 150° C. the mass loss was 0.87%.
Example 7
Preparation of Ziprasidone-hydrobromide Form II
[0072] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was suspended in 30.0 ml methanol at room temperature, then 2.0 ml glacial acetic acidic 33% (w/v) hydrogen bromide solution was added. After stirring the suspension for 16 hours at room temperature the solid was filtered, washed with methanol, and dried under an infrared lamp.
[0073] 2.39 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in the form of Ziprasidone-hydrobromide Form II was obtained.
[0074] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 6.
Example 8
Preparation of Ziprasidone-hydrobromide Form II
[0075] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was suspended in 30.0 ml methanol at room temperature, then 2.0 ml aqueous 48% (w/v) hydrogen bromide solution was added. After stirring the suspension for 16 hours at room temperature the solid was filtered, washed with methanol, and dried under an infrared lamp.
[0076] 2.39 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in a form of Ziprasidone-hydrobromide Form II was obtained.
[0077] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 6.
Example 9
Preparation of Ziprasidone-hydrobromide Form II
[0078] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was suspended in 20.0 ml tetrahydrofuran at room temperature, then with continuous stirring, 2.0 ml glacial acetic acidic 33% (w/v) hydrogen bromide solution was added. The suspension was stirred for 16 hours at a temperature of 60-65° C., after cooling back to room temperature the solid was filtered, washed with methanol, and dried under an infrared lamp.
[0079] 2.38 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in a form of Ziprasidone-hydrobromide Form II was obtained.
[0080] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 6.
[0081] During the thermogravimetric investigation with heating up to 150° C. the mass loss was 0.36%.
Example 10
Preparation of Ziprasidone-hydrobromide Form II
[0082] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in a boiling mixture of 20.0 ml ethanol and 10.0 ml glacial acetic acid, after cooling it was filtered to fiber-free, and 2.0 ml glacial acetic acidic 33% (w/v) hydrogen bromide solution was added into it. The formed suspension was boiled for 16 hour, and then was cooled back to room temperature. The solid was filtered out, washed with methanol, and dried under infrared lamp.
[0083] 2.12 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3 -dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in a form of Ziprasidone-hydrobromide Form II was obtained.
[0084] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 6.
[0085] During the thermogravimetric investigation with heating up to 150° C. the mass loss was 0.58%.
Example 11
Preparation of Ziprasidone-hydrobromide Form II
[0086] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one hydrobromide monohydrate (ziprasidone hydrobromide monohydrate) was dissolved in 6.0 ml formic acid at a temperature of 90-95° C. This solution was added dropvise, with stirring, in 1 min into 40.0 ml methyl tertiary-butyl ether at room temperature. The solid was filtered out from the formed suspension, was washed with methyl tertiary-butyl ether and dried under infrared lamp.
[0087] 1.87 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in a form of Ziprasidone-hydrobromide Form II was obtained.
[0088] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 6.
[0089] During the thermogravimetric investigation with heating up to 150° C. the loss was 0.63%.
Example 12
Preparation of Ziprasidone-hydrobromide Form II
[0090] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one hydrobromide hemihydrate (ziprasidone hydrobromide hemihydrate) in form of Ziprasidone-hydrobromide Form III was dissolved in 6.0 ml formic acid at a temperature of 90-95° C. This solution was added dropvise, with stirring, in 1 min into 20.0 ml methyl tertiary-butyl ether at a temperature of 5-10° C., followed by 30 min. after-stirring, and then the solid was filtered out, washed with 2.0 ml methyl tertiary-butyl ether, and dried at a reduced pressure of 4-6 kPa for 4 hour.
[0091] 1.85 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in a form of Ziprasidone-hydrobromide Form II was obtained.
[0092] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 6.
[0093] During the thermogravimetric investigation with heating up to 150° C. the mass loss was 0.69%.
Example 13
Preparation of Ziprasidone-hydrobromide Form II
[0094] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in a boiling mixture of 20.0 ml ethanol and 10.0 ml glacial acetic acid. The homogeneous solution was stirred with 0.2 g charcoal and 0.2 g silica gel 60 (particle size 0.040-0.063 mm) for 5 min, then it was filtered. 2.0 ml aqueous 48% (w/v) hydrogen bromide solution was added into the clear filtered solution, the formed suspension was boiled for 1 hour, then it was cooled back to room temperature, followed by an hour's after-stirring. Then the solid was filtered out, washed twice with 2.0 ml portions ethanol, and dried at a reduced pressure of 4-6 kPa for 4 hour.
[0095] 2.24 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in a form of Ziprasidone-hydrobromide Form II was obtained.
[0096] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 6.
[0097] During the thermogravimetric investigation with heating up to 150° C. the mass loss was 0.62%.
Example 14
Preparation of Ziprasidone-hydrobromide Form II
[0098] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in a boiling mixture of 63.0 ml tetrahydrofuran and 7.0 ml glacial acetic acid. The homogeneous solution was stirred with 0.2 g charcoal and 0.2 g silica gel 60 (particle size 0.040-0.063 mm) for 5 min, then it was filtered. 2.0 ml glacial acetic acidic 33% (w/v) hydrogen bromide solution was added into the clear filtered solution, the formed suspension was boiled for 1 hour, then it was cooled back to room temperature, followed by an hour's after-stirring. Then the solid was filtered out, washed twice with 2.0 ml portions of tetrahydrofuran, and dried at a reduced pressure of 4-6 kPa for 4 hour.
[0099] 2.30 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in a form of Ziprasidone-hydrobromide Form II was obtained.
[0100] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 6.
[0101] During the thermogravimetric investigation with heating up to 150° C. the mass loss was 0.62%.
Example 15
Preparation of Ziprasidone-hydrobromide Form II
[0102] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one sesquihydrobromide hemiformiate (sesquihydrobromide hemiformiate) in the form of Ziprasidone hydrobromide Form IV prepared according to Example 18 was heated to temperature in the range of 180-200° C., then it was cooled back to room temperature.
[0103] 1.69 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide anhydrate (ziprasidone-hydrobromide anhydrate) in a form of Ziprasidone-hydrobromide Form II was obtained. This product does not absorb water from the air in normal circumstances.
[0104] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 6.
Example 16
Preparation of Ziprasidone-hydrobromide Form III
[0105] 18.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in 72.0 ml formic acid at room temperature. The homogeneous solution was stirred with 1.2 g charcoal and 1.2 g silica gel 60 (particle size 0.040-0.063 mm) for 30 min, then it was filtered. A mixture of 6.0 ml aqueous 48% (w/v) hydrogen bromide solution and 64.0 ml distilled water was added dropvise, with stirring, into the clear filtered solution in 1 hour, followed by 1 hour's after-stirring. Then the solid was filtered out, washed first with a mixture of 10 ml distilled water and 10 ml formic acid then with 20.0 ml tetrahydrofuran, and dried at a reduced pressure of 4-6 kPa for 4 hour.
[0106] 20.9 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3 -dihydro-2H-indol-2-one-hydrobromide hemihydrate (ziprasidone-hydrobromide hemihydrate) in a form of Ziprasidone-hydrobromide Form III was obtained.
[0107] FT-IR spectrum of the product was shown in FIG. 3 . The characteristic bands are at: 3423, 3223, 2917, 1710, 1494, 972 and 741 cm −1 values.
[0108] Powder X-ray diffraction diagram of the product was shown in FIG. 8 , according to it the characteristic 20 values are: 6,986, 11,068, 17,468, 17,744, 19,319, 23,247 and 25,661 [°]
[0109] During the thermogravimetric investigation with heating up to 150° C. the mass loss was 1.67%.
Example 17
Preparation of Ziprasidone-hydrobromide Form III
[0110] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one hydrobromide monohydrate (ziprasidone hydrobromide monohydrate) in the form of Ziprasidone hydrobromide Form I was dissolved in 6.0 ml formic acid at a temperature of 90-95° C. This solution was added dropvise, with stirring, in 1 min into 20.0 ml distilled water at a temperature of 90-95° C. followed by 30 min after-stirring. The solid was filtered out, washed first with 2.0 ml distilled water, then with 2.0 ml methanol, and dried at a reduced pressure of 4-6 kPa for 4 hour.
[0111] 1.95 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one-hydrobromide hemihydrate (ziprasidone-hydrobromide hemihydrate) in a form of Ziprasidone-hydrobromide Form III was obtained.
[0112] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 16.
Example 18
Preparation of Ziprasidone-hydrobromide Form IV
[0113] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in 8.0 ml formic acid at room temperature. The homogeneous solution was stirred with 0.2 g charcoal and 0.2 g silica gel 60 (particle size 0.040-0.063 mm) for 30 min, then it was filtered. A mixture of 2.0 ml aqueous 48% (w/v) hydrogen bromide solution and 10.0 ml methyl-isobutyl ketone was added dropvise, with stirring, in 15 min into the clear filtered solution at a temperature of 25-30° C., followed by an overnight's after-stirring. Then the solid was filtered out, washed with 3.0 ml methyl-isobutyl ketone, and dried under infrared lamp.
[0114] 2.71 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one sesquihydrobromide hemiformiate (ziprasidone sesquihydrobromide hemi-formiate) in a form of Ziprasidone-hydrobromide Form IV was obtained.
[0115] FT-IR spectrum of the product was shown in FIG. 4 . The characteristic bands are at: 3423, 3223, 2917, 1710, 1494, 972 and 741 cm −1 values.
[0116] Powder X-ray diffraction diagram of the product is shown in FIG. 9 , according to it the characteristic 20 values are: 6,986, 11,068, 17,468, 17,744, 19,319,23,247 and 25,661 [°].
[0117] The water content determined with Karl Fischer method: 4.88 %(w/w). The molar contents of HBr and formic acid calculated to the ziprasidone base, and determined by a potentiometric titrimetric and an NMR method: 1.52 (m/m) and 0.62 (m/m), respectively.
Example 19
Preparation of Ziprasidone-hydrobromide Form IV
[0118] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in 10.0 ml formic acid at room temperature. The homogeneous solution was stirred with 0.2 g charcoal and 0.2 g silica gel 60 (particle size 0.040-0.063 mm) for 30 min, then it was filtered. A mixture of 2.0 ml glacial acetic acidic 33% (w/v) hydrogen bromide solution and 10.0 ml ethyl acetate was added dropvise, with stirring, in 15 min into the clear filtered solution at a temperature of 25-30° C., followed by an overnight's after-stirring. Then the solid was filtered out, washed with 3.0 ml ethyl acetate, and dried under infrared lamp.
[0119] 2.23 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one sesquihydrobromide hemiformiate (ziprasidone sesquihydrobromide hemi-formiate) in a form of Ziprasidone-hydrobromide Form IV was obtained.
[0120] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 18.
[0121] The water content determined with Karl Fischer method: 2.91% (w/w). The molar contents of HBr and formic acid calculated to the ziprasidone base, and determined by a potentiometric titrimetric and an NMR method: 1.56 (m/m) and 0.80 (m/m), respectively.
Example 20
Preparation of Ziprasidone-hydrobromide Form IV
[0122] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in 8.0 ml formic acid at room temperature. The homogeneous solution was stirred with 0.2 g charcoal and 0.2 g silica gel 60 (particle size 0.040-0.063 mm) for 30 min, then it was filtered. A mixture of 2.0 ml aqueous 48% (w/v) hydrogen bromide solution and 10.0 ml tetrahydrofuran was added dropvise into the clear filtered solution, with stirring at a temperature of 25-30° C. in 15 min, followed by an overnight's after-stirring. Then the solid was filtered out, washed with 3.0 ml tetrahydrofuran, and dried under infrared lamp.
[0123] 2.87 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one sesquihydrobromide hemiformiate (ziprasidone sesquihydrobromide hemi-formiate) in a form of Ziprasidone-hydrobromide Form IV was obtained.
[0124] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 18.
[0125] The water content determined with Karl Fischer method: 5.28% (w/w). The molar contents of HBr and formic acid calculated to the ziprasidone base, and determined by a potentiometric titrimetric and an NMR method: 1.67 (m/m) and 0.59 (m/m), respectively.
Example 21
Preparation of Ziprasidone-hydrobromide Form IV
[0126] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in 8.0 ml formic acid at room temperature. The homogeneous solution was stirred with 0.2 g charcoal and 0.2 g silica gel 60 (particle size 0.040-0.063 mm) for 30 min, then it was filtered. A mixture of 2.0 ml aqueous 48% (w/v) hydrogen bromide solution and 10.0 ml ethyl acetate was added dropvise into the clear filtered solution, with stirring at a temperature of 25-30° C. in 15 min, followed by an overnight's after-stirring. Then the solid was filtered out, washed with 3.0 ml ethyl acetate, and dried under infrared lamp.
[0127] 2.74 g crystalline 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one sesquihydrobromide hemiformiate (ziprasidone sesquihydrobromide hemi-formiate) in a form of Ziprasidone-hydrobromide Form IV was obtained.
[0128] The IR spectrum and the powder X-ray diffraction diagram of the product are basically the same as in Example 18.
[0129] The water content determined with Karl Fischer method: 4.02% (w/w). The molar contents of HBr and formic acid calculated to the ziprasidone base, and determined by a potentiometric titrimetric and an NMR method: 1.46 (m/m) and 0.57 (m/m), respectively.
Example 22
Preparation of Ziprasidone-hydrobromide Form V
[0130] 2.0 g 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one (ziprasidone base) was dissolved in 10.0 ml formic acid at room temperature. The homogeneous solution was stirred with 0.2 g charcoal and 0.2 g silica gel 60 (particle size 0.040-0.063 mm) for 30 min, then it was filtered. A mixture of 2.0 ml glacial acetic acidic 33% (w/v) hydrogen bromide solution and 10.0 ml methyl isobutyl ketone was added, with stirring, in 1 min into the clear filtered solution, at a temperature of 65-70° C., followed by an overnight's after-stirring. Then the solid was filtered out, washed with 3.0 ml methyl isobutyl ketone, and dried under infrared lamp.
[0131] 2.38 g amorphous 5-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one hydrobromide (ziprasidone hydrobromide) in a form of Ziprasidone-hydrobromide Form V was obtained.
[0132] FT-IR spectrum of the product is shown in FIG. 5 . The characteristic bands are at: 3410, 2808, 1723, 1156, 820, 770 and 736 cm −1 values.
[0133] Powder X-ray diffraction diagram of the product is shown in FIG. 10 , on which lacks of reflection maxima according to the characteristics of this product.
[0134] The water content determined by a Karl Fischer titrimetric method: 5.62%. | The present invention provides pharmaceutically applicable compounds and polymorphs belonging to the ziprasidone hydrobromide compound group with antipsychotic effect. The present invention provides hydrobromide polymorphs of 5-{-2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]-ethyl}-6-chloro-1,3-dihydro-2H-indol-2-one, ziprasidone of Formula (I) having neuroleptic activity. | 2 |
TECHNICAL FIELD
[0001] This invention relates to novel benzimidazolone compounds. These compounds have selective 5-HT 4 receptor agonistic activity. The present invention also relates to a pharmaceutical composition, a method of treatment and use comprising the above compounds for the treatment of disease conditions mediated by 5-HT 4 receptor activity.
BACKGROUND ART
[0002] In general, 5-HT 4 receptor agonists are found to be useful for the treatment of a variety of diseases such as gastroesophageal reflux disease, gastrointestinal disease, gastric motility disorder, non-ulcer dyspepsia, functional dyspepsia, irritable bowel syndrome (IBS), constipation, dyspepsia, esophagitis, gastroesophageral disease, nausea, central nervous system disease, Alzheimer's disease, cognitive disorder, emesis, migraine, neurological disease, pain, cardiovascular disorders, cardiac failure, heart arrhythmia, diabetes and apnea syndrome (See TiPs, 1992, 13, 141; Ford A. P. D. W. et al., Med. Res. Rev., 1993, 13, 633; Gullikson G. W. et al., Drug Dev. Res., 1992, 26, 405; Richard M. Eglen et al, TiPS, 1995, 16, 391; Bockaert J. Et al., CNS Drugs, 1, 6; Romanelli M. N. et al., Arzheim Forsch./Drug Res., 1993, 43, 913; Kaumann A. et al., Naunyn - Schmiedeberg's. 1991, 344, 150; and Romanelli M. N. et al., Arzheim Forsch./Drug Res., 1993, 43, 913). Also, Mosapride is known to be useful for the treatment of diabetes.
[0003] It would be desirable if there were provided 5-HT 4 receptor agonists which have more 5HT 4 receptor agonistic activities.
[0004] U.S. Pat. No. 5,223,511 discloses benzimidazole compounds as 5-HT 4 receptor antagonists. Especially, compounds represented by the following formula is disclosed:
[0005] WO93/18027 discloses benzimidazolone compounds as 5-HT 4 receptor antagonists. Especially, compounds represented by the following formula is disclosed:
[0006] WO99/17772 discloses benzimidazolone compounds as 5-HT 4 receptor agonists and/or antagonists. Especially, compounds represented by the following formula is disclosed:
[0007] WO94/00449 discloses benzimidazolone compounds as 5-HT 4 agonists or antagonists and/or 5-HT 3 antagonists. Especially, compounds represented by the following formula is disclosed:
[0008] There is a need to provide new 5-HT 4 agonists that are good drug candidates. In particular, preferred compounds should bind potently to the 5-HT 4 receptor whilst showing little affinity for other receptors and show functional activity as agonists. They should be well absorbed from the gastrointestinal tract, be metabolically stable and possess favorable pharmacokinetic properties. When targeted against receptors in the central nervous system they should cross the blood brain barrier freely and when targeted selectively against receptors in the peripheral nervous system they should not cross the blood brain barrier. They should be non-toxic and demonstrate few side-effects. Furthermore, the ideal drug candidate will exist in a physical form that is stable, non-hygroscopic and easily formulated.
BRIEF DISCLOSURE OF THE INVENTION
[0009] It has now surprisingly been found that compounds of this invention have strong selective 5-HT 4 agonistic activity, and thus are useful for the treatment of disease conditions mediated by 5-HT 4 activity such as gastroesophageal reflux disease, gastrointestinal disease, gastric motility disorder, non-ulcer dyspepsia, functional dyspepsia, irritable bowel syndrome (IBS), constipation, dyspepsia, esophagitis, gastroesophageral disease, nausea, central nervous system disease, Alzheimer's disease, cognitive disorder, emesis, migraine, neurological disease, pain, cardiovascular disorders, cardiac failure, heart arrhythmia, diabetes and apnea syndrome (especially caused by an opioid administration).
[0010] Further, the compounds of the present invention show a reduced QT prolongation by introducing a polar group into R 3 of the formula (I). QT prolongation is known to have a potential liability to produce fatal cardiac arrhythmias of Torsades de Pointes (TdP). The ability to prolong the cardiac action potential duration was identified as being due to an action at the HERG potassium channel. For example, drugs withdrawn from the market due to QT prolongation, such as Cisapride and Terfenadine, are known to be potent HERG potassium channel blocker (Expert Opinion of Pharmacotherapy.; 2, pp 947-973, 2000) Inhibitory activity at HERG channel was estimated from affinity for HERG type potassium channel was investigated by checking [ 3 H]dofetilide binding, which can predict inhibitory activity at HERG channel (Eur. J. Pharmacol., 430, pp 147-148, 2001).
[0011] The compounds of the present invention may show less toxicity, good absorption, distribution, good solubility, low protein binding affinity, less drug-drug interaction, and good metabolic stability.
[0012] The present invention provides a compound of the following formula (1) or a pharmaceutically acceptable salt thereof.
wherein
Het represents a heterocyclic group having one nitrogen atom, to which B binds directly, and from 4 to 7 carbon atoms, and said heterocyclic group being unsubstituted or substituted by 1 to 4 substituents independently selected from the group consisting of substituents α 1 ; A represents an alkylene group having from 1 to 4 carbon atoms; B represents a covalent bond or an alkylene group having from 1 to 5 carbon atoms, and said alkylene group being unsubstituted or substituted by an oxo group when R 3 represents a heterocyclic group; R 1 represents an isopropyl group or a cyclopentyl group; R 2 independently represents a halogen atom or an alkyl group having from 1 to 4 carbon atoms; m is 0, 1, 2, 3 or 4; and R 3 represents
(i) a cycloalkyl group having from 3 to 8 carbon atoms, and said cycloalkyl group being substituted by 1 to 5 substituents independently selected from the group consisting of substituents α 2 , or (ii) a heterocyclic group having from 3 to 8 atoms, and said heterocyclic group being unsubstituted or substituted by 1 to 5 substituents independently selected from the group consisting of substituents β,
said substituents α 1 are independently selected from a hydroxy group and an amino group; said substituents α 2 are independently selected from a hydroxy group, an amino group, a hydroxy-substituted alkyl group having from 1 to 4 carbon atoms, a carboxyl group and an alkoxy group having from 1 to 4 carbon atoms; and said substituents β are independently selected from a hydroxy group, a hydroxy-substituted alkyl group having from 1 to 4 carbon atoms, a carboxyl group, an amino group, an alkyl group having from 1 to 4 carbon atoms, an amino-substituted alkyl group having from 1 to 4 carbon atoms and a carbamoyl group.
[0024] The invention also provides a compound of the formula (I):
or a pharmaceutically acceptable salt thereof, wherein:
Het represents a heterocyclic group having one nitrogen atom, to which B binds directly, and from 4 to 7 carbon atoms, and said heterocyclic group being unsubstituted or substituted by 1 to 4 substituents independently selected from the group consisting of substituents α 1 ; A represents an alkylene group having from 1 to 4 carbon atoms; B represents a covalent bond or an alkylene group having from 1 to 5 carbon atoms, and said alkylene group being unsubstituted or substituted by an oxo group when R 3 represents a heterocyclic group; R 1 represents an isopropyl group or a cyclopentyl group; R 2 independently represents a halogen atom or an alkyl group having from 1 to 4 carbon atoms; m is 0, 1, 2, 3 or 4; and R 3 represents
(i) a cycloalkyl group having from 3 to 8 carbon atoms, and said cycloalkyl group being substituted by 1 to 5 substituents independently selected from the group consisting of substituents α 2 , or (ii) a heterocyclic group having from 3 to 8 atoms, and said heterocyclic group being unsubstituted or substituted by 1 to 5 substituents independently selected from the group consisting of substituents β,
said substituents α 1 are independently selected from a hydroxy group and an amino group; said substituents α 2 are independently selected from a hydroxy group, an amino group, a hydroxy-substituted alkyl group having from 1 to 4 carbon atoms, a carboxyl-substituted alkyl group having 1 to 4 carbon atoms, a carboxyl group and an alkoxy group having from 1 to 4 carbon atoms; and said substituents β are independently selected from a hydroxy group, a hydroxy-substituted alkyl group having from 1 to 4 carbon atoms, a carboxyl-substituted alkyl group having 1 to 4 carbon atoms, a carboxyl group, an amino group, an alkyl group having from 1 to 4 carbon atoms, an amino-substituted alkyl group having from 1 to 4 carbon atoms and a carbamoyl group.
[0036] Also, the present invention provides a pharmaceutical composition for the treatment of disease conditions mediated by 5-HT 4 receptor, in a mammalian subject, which comprises administering to said subject a therapeutically effective amount of a compound of formula (I) or pharmaceutically acceptable salts thereof.
[0037] Further, the present invention also provides a pharmaceutical composition for the treatment of diseases selected from gastroesophageal reflux disease, gastrointestinal disease, gastric motility disorder, non-ulcer dyspepsia, functional dyspepsia, irritable bowel syndrome (IBS), constipation, dyspepsia, esophagitis, gastroesophageral disease, nausea, central nervous system disease, Alzheimer's disease, cognitive disorder, emesis, migraine, neurological disease, pain, cardiovascular disorders, cardiac failure, heart arrhythmia, diabetes and apnea syndrome, or the like, which comprises a therapeutically effective amount of the benzimidazolone compound of formula (I) or its pharmaceutically acceptable salt together with a pharmaceutically acceptable carrier.
[0038] Also, the present invention provides a method of the treatment of a mammal, including a human, to treat a disease conditions mediated by 5-HT 4 receptor, in a mammalian subject, which comprises administering to said subject a therapeutically effective amount of a compound of formula (I) or pharmaceutically acceptable salts thereof. Further, the present invention provides a method for the treatment of the disease conditions as mentioned above. Furthermore, the present invention provides use of the compound of formula (I) or pharmaceutically acceptable salts thereof in the manufacture of a medicament for the treatment of disease conditions mediated by 5-HT 4 receptor activity, in a mammalian subject. The conditions mediated by 5-HT 4 receptor activity include those diseases or disorders described as above.
[0039] Also, the present invention provides a compound of the following formula (2-A′) or a salt thereof:
wherein
R a represents a hydrogen atom or a N-protecting group; Het represents a heterocyclic group having one nitrogen atom, to which B binds directly, and from 4 to 7 carbon atoms, and said heterocyclic group being unsubstituted or substituted by 1 to 4 substituents independently selected from the group consisting of substituents α 1 ; A represents an alkylene group having from 1 to 4 carbon atoms; B represents a covalent bond or an alkylene group having from 1 to 5 carbon atoms, and said alkylene group being unsubstituted or substituted by an oxo group when R 3 represents a heterocyclic group; R 3 represents
(i) a cycloalkyl group having from 3 to 8 carbon atoms, and said cycloalkyl group being substituted by 1 to 5 substituents independently selected from the group consisting of substituents α 2 , or (ii) a heterocyclic group having from 3 to 8 atoms, and said heterocyclic group being unsubstituted or substituted by 1 to 5 substituents independently selected from the group consisting of substituents β,
said substituents α 1 are independently selected from a hydroxy group and an amino group; said substituents α 2 are independently selected from a hydroxy group, an amino group, a hydroxy-substituted alkyl group having from 1 to 4 carbon atoms, a carboxyl group and an alkoxy group having from 1 to 4 carbon atoms; and said substituents β are independently selected from a hydroxy group, a hydroxy-substituted alkyl group having from 1 to 4 carbon atoms, a carboxyl group, an amino group, an alkyl group having from 1 to 4 carbon atoms, an amino-substituted alkyl group having from 1 to 4 carbon atoms and a carbamoyl group,
DETAILED DESCRIPTION OF THE INVENTION
[0050] As used herein, the term “heterocyclic” of “Het” means a heterocyclic group having one nitrogen atom and from 4 to 7 carbon atoms such as
[0051] As used herein, the term “alkylene” in “A” means straight or branched chain saturated radicals having 1 to 4 carbon atoms, including, but not limited to methylene, ethylene, n-propylene, isopropylene, n-butylene, isobutylene, sec-butylene, tert-butylene. The “alkylene” in “A” represents preferably a methylene group, an ethylene group or a propylene group; more preferably a methylene group or an ethylene group; most preferably a methylene group.
[0052] As used herein, the term “alkylene” in “B” means straight or branched chain saturated radicals having 1 to 5 carbon atoms, including, but not limited to methylene, ethylene, n-propylene, isopropylene, n-butylene, isobutylene, sec-butylene, tert-butylene, n-pentylene, isopentylene, sec-pentylene, tert-pentylene. The “alkylene” in “B” represents preferably an alkylene group having from 1 to 4 carbon atoms; more preferably an alkylene group having from 1 to 3 carbon atoms; much more preferably a methylene group or an ethylene group; further more preferably a methylene group.
[0053] As used herein, the term “halogen” in “R 2 ” means fluoro, chloro, bromo and iodo, preferably fluoro or chloro.
[0054] As used herein, the term “alkyl” in “R 2 ”; “alkyl” of “a hydroxy-substituted alkyl group” and “an alkoxy group having from 1 to 4 carbon atoms” in “substituents α 2 ”; “alkyl” in “substituents β”; and “alkyl” of “a hydroxy-substituted alkyl group” and “an amino-substituted alkyl group” in “substituents β” mean straight or branched chain saturated radicals having 1 to 4 carbon atoms, including, but not limited to methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, ten-butyl.
[0055] As used herein, the term “cycloalkyl” in “R 3 ” means cyclic alkyl group having 3 to 8 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and etc.
[0056] As used herein, the term “heterocyclic” of “R 3 ” means a heterocyclic ring which has one or more hetero atoms in the ring, preferably has 2 to 6 carbon atoms and 1 to 3 heteroatoms, including aziridinyl, azetidinyl, piperidinyl, morpholinyl(including morpholino), pyrrolidinyl, pyrazolidinyl, piperazinyl, tetrahydropyrazolyl, pyrazolinyl, tetrahydropyranyl and etc.
[0057] The term “treating”, as used herein, refers to reversing, alleviating, inhibiting the progress of, or preventing the disorder or condition to which such term applies, or one or more symptoms of such disorder or condition. The term “treatment” as used herein refers to the act of treating, as “treating” is defined immediately above.
[0058] A preferred compound of formula (I) of this invention is that wherein Het represents a heterocyclic group selected from
said heterocyclic group being unsubstituted or substituted by 1 to 3 substituents independently selected from the group consisting of substituents α 1 ; and
A represents an alkylene group having from 1 to 3 carbon atoms.
[0060] A more preferred compound of formula (I) of this invention is that wherein
Het represents a group of formula
and this group being unsubstituted or substituted by one substituent selected from the group consisting of substituents α 1 ;
A represents an alkylene group having from 1 to 2 carbon atoms; B represents an alkylene group having from 1 to 4 carbon atoms, and said alkylene group being unsubstituted or substituted by an oxo group when R 3 represents a heterocyclic group; R 2 independently represents a halogen atom or an alkyl group having from 1 to 2 carbon atoms; m is 0, 1 or 2; and R 3 represents
(i) a cycloalkyl group having from 4 to 7 carbon atoms, and said cycloalkyl group being substituted by 1 to 3 substituents independently selected from the group consisting of substituents α 2 , or (ii) a heterocyclic group having from 4 to 7 atoms, and said heterocyclic group being unsubstituted or substituted by 1 to 3 substituents independently selected from the group consisting of substituents β.
[0068] Also, a further preferred compound of formula (I) of this invention is the compound or its pharmaceutically acceptable salt wherein
Het represents a group of formula
and this group being unsubstituted or substituted by one substituent selected from the group consisting of substituents α 1 ;
A represents a methylene group; B represents an alkylene group having from 1 to 2 carbon atoms; R 1 represents an isopropyl group; R 2 independently represents a fluorine atom, a chlorine atom or a methyl; and R 3 represents
(i) a cycloalkyl group having from 5 to 7 carbon atoms, and said cycloalkyl group being substituted by 1 to 2 substituents independently selected from the group consisting of substituents α 2 , or (ii) a heterocyclic group having from 5 to 7 atoms, and said heterocyclic group being unsubstituted or substituted by 1 to 2 substituents independently selected from the group consisting of substituents β,
said substituents α 2 are independently selected from a hydroxy group, an amino group and an alkoxy group having from 1 to 2 carbon atoms; and said substituents β are independently selected from a hydroxy group, a hydroxy-substituted alkyl group having from 1 to 2 carbon atoms, a carboxyl group, an amino group, an amino-substituted alkyl group having from 1 to 2 carbon atoms and a carbamoyl group.
[0079] A further preferred compound of formula (I) of this invention is the compound or its pharmaceutically acceptable salt wherein
Het represents a group of formula
A represents a methylene group; B represents a methylene group; R 1 represents an isopropyl group; R 2 represents a fluorine atom; m is 0 or 1; and R 3 represents
(i) a cycloalkyl group having from 5 to 6 carbon atoms, and said cycloalkyl group being substituted by 1 to 2 substituents independently selected from the group consisting of substituents α 2 , or (ii) a heterocyclic group having from 5 to 6 atoms, and said heterocyclic group being unsubstituted or substituted by 1 to 2 substituents independently selected from the group consisting of substituents β,
said substituents α 2 are independently selected from a hydroxy group and an amino group; and said substituents β are independently selected from a hydroxy group and an amino group.
[0090] A further preferred compound of formula (I) of this invention is the compound or its pharmaceutically acceptable salt, wherein
Het represents a group of formula
A represents a methylene group; B represents a methylene group; R 1 represents an isopropyl group; R 2 represents a fluorine atom; m is 0; and R 3 represents
(i) a cyclohexyl group substituted by 1 to 2 substituents independently selected from a hydroxy group or an amino group, or (ii) a heterocyclic group having from 6 atoms, and said heterocyclic group being substituted by a hydroxy group or an amino group.
[0099] Most preferred compounds of formula (I) of this invention is the compound or its pharmaceutically acceptable salt, wherein
Het represents a group of formula
A represents a methylene group; B represents a methylene group; R 1 represents an isopropyl group; R 2 represents a fluorine atom; m is 0; and R 3 represents
(i) a cyclohexyl group substituted by 1 or 2 hydroxy group (especially dihydroxycyclohexyl), or (ii) a tetrahydropyran group substituted by 1 or 2 hydroxy group (especially hydroxytetrahydropyranyl).
[0108] In the compounds of formula (I) or the pharmaceutically acceptable salt, R 2 preferably represents a fluorine atom, a chlorine atom, a methyl group or an ethylene group; more preferably a fluorine atom, a chlorine atom, a methyl group; most preferably a fluorine atom.
[0109] In the compounds of formula (I) or the pharmaceutically acceptable salt, m is preferably 0, 1 or 2; more preferably 0 or 1; much more preferably 0.
[0110] Preferred individual compound of this invention is:
N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide; N-({1-[(trans-1,4-dihydroxyhexyl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide; N-({1-[(cis-1,4-dihydroxyhexyl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide; 6-fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide; 4-{[4-({[(3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)carbonyl]amino}methyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-carboxylic acid; 1-{[4-({[(3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)carbonyl]amino}methyl)piperidin-1-yl]methyl}cyclopentanecarboxylic acid; and 1-{[4-({[(3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)carbonyl]amino}methyl)piperidin-1-yl]methyl}cyclobutanecarboxylic acid;
or a pharmaceutically acceptable salt thereof.
[0118] A preferred compound of formula (2-A′) of this invention is that wherein
R a represents a hydrogen atom or a t-butoxycarbonyl group; Het represents a group of formula
A represents an methylene group; B represents an methylene group; and R 3 represents hydroxytetrahydropyranyl or dihydroxycyclohexyl.
General Synthesis
[0123] The compounds of the present invention may be prepared by a variety of processes well known for the preparation of compounds of this type, for example as shown in the following reaction Schemes. Unless otherwise indicated R 1 through R 3 and m in the following reaction Schemes and discussion are defined as above. The term “protecting group”, as used hereinafter, means a hydroxy or amino protecting group which is selected from typical hydroxy or amino protecting groups described in Protective Groups in Organic Synthesis edited by T. W. Greene et al. (John Wiley & Sons, 1991); All starting materials in the following general syntheses may be commercially available or obtained by conventional methods known to those skilled in the art.
[0124] The compound of formula (I), wherein Het is
is prepared by the following synthesis. And the compound of formula (I), wherein Het is other than
can be prepared by a similar manner or a method known to a skilled person.
[0125] In Steps 1a, 1b, 1d, 2a, 2c, 2e, 3a, 3c, 3d of the following schemes, each reaction is preferably carried out in the presence of a base. There is no particular restriction on the nature of the bases used, and any base commonly used in reactions of this type may equally be used here. The base employed includes, for example, alkali metal hydroxides, such as lithium hydroxide, sodium hydroxide and potassium hydroxide; alkali metal carbonates such as sodium carbonate and potassium carbonate; alkali metal hydrides such as sodium hydride, potassium hydride and lithium hydride; alkali metal alkoxides such as sodium methoxide, sodium ethoxide, potassium t-butoxide and lithium methoxide; alkyllithiums such as butyllithium and methyllithium; lithium amides such as lithium diethylamides, lithium diisopropylamide and lithium bis(trimethylsilyl)amide; alkali metal hydrogencarbonates such as sodium hydrogencarbonate and potassium hydrogencarbonate; and tertiary organic amines such as triethylamine, dimethylaniline, pyridine, 4-dimethylaminopyridine, 1,5-diazabicyclo[4.3.0]non-5-ene, 1,8-diazabicyclo [5.4.0]undec-7-ene and N,N-diisopropylethylamine.
[0000] Synthesis of Benzimidazolone (1-A):
[0126] The following reaction Schemes illustrate the preparation of benzimidazolone compounds of formula 1-A.
[0127] In the above formulae, Z represents ‘halo’, such as a chlorine, bromine or iodine atom.
[0000] Step 1a
[0128] In step 1a, an amine compound of formula 1-3 can be prepared by the reductive amination of the alkanone compound (having from 1 to 4 carbon atoms) with an amine compound of formula 1-1 in the presence or absence of a reducing agent or a metal agent in an inert solvent.
[0129] The reaction is normally and preferably effected in the presence of a solvent. There is no particular restriction on the nature of the solvent to be employed, provided that it has no adverse effect on the reaction or on the reagents involved and that it can dissolve the reagents, at least to some extent. Examples of suitable aqueous or non-aqueous organic solvents include: alcohols, such as methanol, ethanol or isopropanol; ethers, such as tetrahydrofuran (THF), dimethoxyethane or dioxane; acetonitrile; N,N′-dimethylformamide; dimethylsulfoxide; acetic acid; and halogenated hydrocarbon, such as dichloromethane, dichloroethane or chloroform.
[0130] The reaction can take place over a wide range of temperatures, and the precise reaction temperature is not critical to the invention. The preferred reaction temperature will depend upon such factors as the nature of the solvent, and the starting material or reagent used. However, in general, it is convenient to carry out the reaction with reducing agents at a temperature of from −78° C. to 100° C., more preferably from about −20° C. to 60° C. The time required for the reaction may also vary widely, depending on many factors, notably the reaction temperature and the nature of the reagents and solvent employed. However, provided that the reaction is effected under the preferred conditions outlined above, a period of 5 minutes to 1 week, more preferably 30 minutes to 24 hours, will usually suffice. In the case of the reaction with metal reagents, it is convenient to carry out the reaction at a temperature of from 20° C. to 100° C., preferably from about 20° C. to 60° C. for 10 minutes to 48 hours, preferably 30 minutes to 24 hours.
[0131] Suitable reducing reagents are those typically used in the reduction including, for example, sodium borohydride, sodium cyanoborohydride or sodium triacetoxyborohydride.
[0132] The combination of metal reagents and hydrogen gas can be also employed as reducing reagent. Example of suitable metal reagents include palladium-carbon, palladiumhydroxide-carbon, platinumoxide, platinum-carbon, ruthenium-carbon, rhodium-aluminumoxide and tris[triphenyphosphine]rhodiumchloride. The reduction with metal reagents may be carried out under hydrogen atmosphere at a pressure ranging from 1 to 100 atm, preferably from 1 to 10 atm.
[0133] This reduction can be carried out after formation of the corresponding enamine of the alkanone compound or imine of the alkanone compound in a reaction-inert solvent such as benzene, toluene, or xylene at a temperature in the range from 20 to 130° C. for 1 hour to 1 week.
[0134] Alternatively, the compound of formula 1-3 can be prepared by alkylation of the compound of formula 1-1 with an alkyl halide of formula of Z-R 1 wherein Z is halo (halo is chloro, bromo, or iodo) as essentially the same condition as below (Step 1d), preferably in the presence of a base.
[0000] Step 1b
[0135] In this step, a compound of formula 1-3 can be prepared by alkylation of a compound of formula 1-2 with compound of formula R 1 —NH 2 .
[0136] The reaction can take place over a wide range of temperatures, and the precise reaction temperature is not critical to the invention. The preferred reaction temperature will depend upon such factors as the nature of the solvent, and the starting material or reagent used. However, in general, it is convenient to carry out the reaction at a temperature of from 0° C. to 150° C., more preferably from 20° C. to 120° C. The time required for the reaction may also vary widely, depending on many factors, notably the reaction temperature and the nature of the reagents and solvent employed. However, provided that the reaction may be effected under the preferred conditions outlined above, a period of from 5 minutes to 48 hours, more preferably from 30 minutes to 24 hours, will usually suffice.
[0000] Step 1c
[0137] A compound of formula 1-4 can be prepared by reduction of a compound of fomula 1-3 with a suitable reducing agent, such as sodium borohydride (NaBH 4 ), lithium aluminumhydride (LAH), diborane, hydrogen and a metal catalyst, iron and hydrochoric acid, stannic chloride and hydrochoric acid, zinc and hydrochoric acid, formic acid, borane dimethylsulfide complex, borane-THF, (preferably hydrogen and a metal catalyst), usually in excess, in a reaction inert solvent such as methanol, ethanol, propanol, butanol, terahydrofuran (THF) (preferably methanol or ethanol), generally at temperature of −78° C. to 60° C., preferably from about 0° C. to 45° C. for 5 minutes to 24 hours, preferably 60 minutes to 12 hours.
[0000] Step 1d
[0138] In step 1d, an amine compound of formula 1-4 can be prepared by the reductive amination of the alkanone compound with an amine compound of formula 1-5 in a similar condition in step 1a.
[0139] Alternatively, a compound of formula 1-4 can be prepared by alkylation of a compound of formula 1-5 with compound of formula Z-R 1 .
[0140] The reaction can take place over a wide range of temperatures, and the precise reaction temperature is not critical to the invention. The preferred reaction temperature will depend upon such factors as the nature of the solvent, and the starting material or reagent used. However, in general, it is convenient to carry out the reaction at a temperature of from 0° C. to 120° C., more preferably from 0° C. to 70° C. The time required for the reaction may also vary widely, depending on many factors, notably the reaction temperature and the nature of the reagents and solvent employed. However, provided that the reaction may be effected under the preferred conditions outlined above, a period of from 5 minutes to 48 hours, more preferably from 30 minutes to 24 hours, will usually suffice.
[0000] Step 1e
[0141] A compound of formula 1-A can be prepared by cyclization of a compound of formula 1-4 with a suitable carbonylating agent such as carbonyldiimidazole, trichloromethyl chloroformate, triphosgene and urea (preferably carbonyldiimidazole), usually in excess, in a reaction inert solvent such as dimethoxyethane, dioxane, acetonitrile, N,N′-dimethylformamide, dimethylsulfoxide, dichloromethane, dichloroethane, chloroform, or terahydrofuran (THF) (preferably THF), generally at temperature of −78° C. to 120° C., preferably from about 20° C. to 100° C. for 5 minutes to 24 hours, preferably 60 minutes to 12 hours.
[0142] Alternatively, the compound of 1-A (wherein R 1 is isopropyl as shown in Scheme 1b) can be prepared from an alkenyl-benzimidazolone compound of formula 1-6 according to the following Scheme 1b in a reaction condition known to a skilled person.
Synthesis of Amine Moiety (2-A):
[0143] The following reaction Schemes illustrate the preparation of piperidine compounds of formula (2-A).
[0144] In the above formulae, PG represents a protecting group. The term “protecting group”, as used herein, means an amino protecting group which is selected from typical amino protecting groups described in Protective Groups in Organic Synthesis edited by T. W. Greene et al. (John Wiley & Sons, 1991). Typical amino protecting groups include benzyl, C 2 H 5 O(C═O)—, CH 3 (C═O)—, tert-butyldimethylsilyl (TBS), tert-butyldiphenylsilyl, benzyloxycarbonyl represented as Z and tert-buthoxycarbonyl represented as t-Boc or Boc.
[0145] A compound of formula 2-2 can be prepared by alkylation or reductive amination of a compound of formula 2-1 with a compound of formula alkyl-R 3 , halo-R 3 , or H(C═O)—R 3 in a similar condition to step 1a. When —B—R 3 represents 4-hydroxytetrahydropyranylmethyl, this alkylation can be done by using a 1,6-dioxaspiro[2.5]octane compound.
[0146] Then, this reaction is followed by deprotection to obtain a compound of formula 1-A. This deprotection may be carried out according to procedures known to those skilled in the art to give the compound of formula of 2-A.
[0147] Alternatively, the compound of formula (2-A) can be prepared from a piperidine compound of formula 2-3 according to the following Scheme 2b with a reaction condition known to a skilled person.
[0148] For example, in step 2c, the compound 2-4 may be prepared by alkylation or reductive amination in essentially the same condition as one described in step 2a of Scheme 2a. Then, the reduction in step 2d may be carried out in the presence of a reducing reagent such as LiAlH 4 in a reaction inert solvent such as THF. Suitable reaction temperature ranges from about −78° C. to about 100° C., preferably from about −30° C. to about 40° C.
[0149] The compound of formula (1-A) can be prepared from a piperidine compound of formula 2-5 according to the following Scheme 2c with a reaction condition known to a skilled person
[0150] For example, in step 2e, the compounds 2-6 may be prepared by alkylation or reductive amination in a similar condition to one described in step 2a of scheme 2a. Then, the reduction in step 2f may be carried out in the presence of a H 2 and a hydrogenation catalyst such as PtO 2 in a reaction inert solvent such as THF. Suitable reaction temperature ranges from about −78° C. to about 100° C., preferably from about −30° C. to about 40° C.
[0000] Synthesis of the Compound of Formula (I):
[0151] The following reaction Schemes illustrate the preparation of benzimidazolone compounds of formula I.
Step 3a:
[0152] A compound of formula 3-1 can be prepared by carbonylation of a compound of formula 1-A with a compound of formula 2-A in the presence of a suitable carbonylating agent such as carbonyldiimidazole, trichloromethyl chloroformate, triphosgene, 4-nitrophenyl chloroformate, or urea (preferably triphosgene), usually in excess, in a reaction inert solvent such as, dimethoxyethane, dioxane, acetonitrile, N,N′-dimethylformamide, dimethylsulfoxide, dichloromethane, dichloroethane, terahydrofuran (THF), benzene, toluene, or chloroform (preferably THF), generally at temperature of −78° C. to 120° C., preferably from about 0° C. to 90° C. for 5 minutes to 24 hours, preferably 60 minutes to 12 hours.
[0000] Step 3b:
[0153] A compound of formula 3-2 is prepared by deprotection of a compound of formula 3-1 with an acid such as hydrochloride,
[0000] Step 3c:
[0154] A compound of formula (Ia) can be prepared by alkylation or reductive amination in a similar condition to one described in step 2a of Scheme 2a.
[0155] Alternatively, the compound of formula (Ia) can be prepared from alkyl-benzimidazolone compounds according to the following Scheme 3b in a reaction condition known to a skilled person.
[0156] For example, in step 3d, the compound of formula 1-A can be reacted with a compound of formula 2-A in the presence of a carbonylating agent such as carbonyldiimidazole, trichloromethyl chloroformate, triphosgene, 4-nitrophenyl chloroformate, or urea (preferably triphosgene), usually in excess, in a reaction inert solvent such as dimethoxyethane, dioxane, acetonitrile, N,N′-dimethylformamide, dimethylsulfoxide, dichloromethane, dichloroethane, terahydrofuran (THF), benzene, toluene, or chloroform (preferably THF), generally at temperature of −78° C. to 120° C., preferably from about 0° C. to 90° C. for 5 minutes to 24 hours, preferably 60 minutes to 12 hours.
[0157] The compound of formula 7 can be prepared by using a reaction known to a skilled person. For example, the compound of formula 7 can be prepared from a compound of formula 3 according to the following Scheme 3c in a reaction condition known to a skilled person.
[0158] In the above Schemes from 1a to 3c, examples of suitable solvents include a mixture of any two or more of those solvents described in each Step.
[0159] The compounds of formula (I), and the intermediates above-mentioned preparation methods can be isolated and purified by conventional procedures, such as distillation, recrystallization or chromatographic purification.
[0160] The optically active compounds of this invention can be prepared by several methods. For example, the optically active compounds of this invention may be obtained by chromatographic separation, enzymatic resolution or fractional crystallization from the final compounds.
[0161] Several compounds of this invention possess an asymmetric center. Hence, the compounds can exist in separated (+)- and (−)-optically active forms, as well as in racemic one thereof. The present invention includes all such forms within its scope. Individual isomers can be obtained by known methods, such as optically selective reaction or chromatographic separation in the preparation of the final product or its intermediate.
[0162] The subject invention also includes isotopically-labelled compounds, which are identical to those recited in formula (I), but for the fact that one or more atoms are replaced by an atom having an atomic mass or mass number different from the atomic mass or mass number usually found in nature. Examples of isotopes that can be incorporated into compounds of the invention include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, fluorine and chlorine, such as 2 H, 3 H, 13 C, 14 C, 15 N, 18 O, 17 O, 31 P, 32 P, 35 S, 18 F, and 36 Cl, respectively. Compounds of the present invention, prodrugs thereof, pharmaceutically acceptable esters of said compounds and pharmaceutically acceptable salts of said compounds, of said esters or of said prodrugs which contain the aforementioned isotopes and/or other isotopes of other atoms are within the scope of this invention. Certain isotopically-labelled compounds of the present invention, for example those into which radioactive isotopes such as 3 H and 14 C are incorporated, are useful in drug and/or substrate tissue distribution assay. Tritiated, i.e., 3 H, and carbon-14, i.e., 14 C, isotopes are particularly preferred for their ease of presentation and detectability. Further, substitution with heavier isotopes such as deuterium, i.e., 2 H, can afford therapeutic advantage resulting from greater metabolic stability, for example increased in vivo half-life or reduced dosage requirement and, hence, may be preferred in some circumstances. Isotopically labeled compounds of formula (I) of this invention and prodrugs thereof can generally be prepared by carrying out the procedure disclosed in above-disclosed Schemes and/or Examples and Preparations below, by submitting a readily available isotopically labeled reagent for a non-isotopically labeled reagent.
[0163] The present invention includes salt forms of the compounds (I) as obtained.
[0164] Pharmaceutically acceptable salts of the compounds of formula (I) include the acid addition and base addition salts (including disalts) thereof.
[0165] Pharmaceutically acceptable non-toxic salts of compounds of formula (I) may be prepared by conventional techniques by, for example, contacting said compound with a stoichiometric amount of an appropriate alkali or alkaline earth metal (sodium, potassium, calcium and magnesium) hydroxide or alkoxide in water or an appropriate organic solvent such as ethanol, isopropanol, mixtures thereof, or the like.
[0166] The bases which are used to prepare the pharmaceutically acceptable base addition salts of the acidic compounds of this invention of formula (I) are those which form non-toxic base addition salts, i.e., salts containing pharmaceutically acceptable cations, such as adenine, arginine, cytosine, lysine, benethamine (i.e., N-benzyl-2-phenyletylamine), benzathine (i.e., N,N-dibenzylethylenediamine), choline, diolamine (i.e., diethanolamine), ethylenediamine, glucosamine, glycine, guanidine, guanine, meglumine (i.e., N-methylglucamine), nicotinamide, olamine (i.e., ethanolamine), ornithine, procaine, proline, pyridoxine, serine, tyrosine, valine and tromethamine (i.e., tris or tris(hydroxymethyl)aminomethane). The base addition salts can be prepared by conventional procedures.
[0167] Insofar as the certain compounds of this invention are basic compounds, they are capable of forming a wide variety of different salts with various inorganic and organic acids.
[0168] The acids which are used to prepare the pharmaceutically acceptable acid addition salts of the basic compounds of this invention of formula (I) are those which form non-toxic acid addition salts, i.e., salts containing pharmaceutically acceptable anions, such as the chloride, bromide, iodide, nitrate, sulfate or bisulfate, phosphate or acid phosphate, acetate, lactate, citrate or acid citrate, tartrate or bi-tartrate, succinate, malate, fumarate, gluconate, saccharate, benzoate, methanesulfonate, ethanesulfonate, benzenesulfonate, p-toluenesulfonate, adipate, aspartate camsylate, edisylate (i.e., 1,2-ethanedisulfonate), estolate (i.e., laurylsulfate), gluceptate (i.e., gluscoheptonate), gluconate, 3-hydroxy-2-naphthoate, xionofoate (i.e., 1-hydrroxy-2-naphthoate), isethionate, (i.e., 2-hydroxyethanesulfonate), mucate (i.e., galactarate), 2-naphsylate (i.e., naphthalenesulphonate, stearate, cholate, glucuronate, glutamate, hippurate, lactobionate, lysinate, maleate, mandelate, napadisylate, nicatinate, polygalacturonate, salicylate, sulphosalicylate, tannate, tryptophanate, borate, carbonate, oleate, phthalate and pamoate (i.e., 1.1′-methylene-bis-(2-hydroxy-3-naphthoate). Of these, we prefer edisylate (including hemi-edisylate) and hydrochloride. The acid addition salts can be prepared by conventional procedures.
[0169] For a review of on suitable salts see Berge et al., J. Pharm. Sci., 66, 1-19, 1977.
[0170] The present invention includes salt forms of the compounds of formula (2-A′) as obtained.
[0171] Compounds of formula (2-A′) may be capable of forming cations. Cations of compounds of formula (2-A′) may be prepared by conventional techniques by, for example, contacting said compound with a stoichiometric amount of an appropriate alkali or alkaline earth metal (sodium, potassium, calcium and magnesium) hydroxide or alkoxide in water or an appropriate organic solvent such as ethanol, isopropanol, mixtures thereof, or the like.
[0172] The bases used to prepare the base addition salts of the acidic compounds of formula (2-A′) are those which form base addition salts. Such base addition salts include pharmaceutically acceptable base addition salts as described above and salts containing cations, such as. triethylamine, pyridine and ammonia.
[0173] The compounds of formula (2-A′) are capable of forming a wide variety of different salts with various inorganic and organic acids.
[0174] The acids used to prepare the acid addition salts of the compound of formula (2-A′) are those which form acid addition salts. Such acid addition salts include pharmaceutically acceptable acid addition salts as described above and salts containing anions, such as cyanide.
[0175] Also included within the scope of this invention are bioprecursors (also called pro-drugs) of the compounds of the formula (I). A bioprecursor of a compound of the formula (I) is a chemical derivative thereof which is readily converted back into the parent compound of the formula (I) in biological systems. In particular, a bioprecursor of a compound of the formula (I) is converted back to the parent compound of the formula (I) after the bioprecursor has been administered to, and absorbed by, a mammalian subject, e.g., a human subject. For example, it is possible to make a bioprecursor of the compounds of formula (I) in which one or both of L and W include hydroxy groups by making an ester of the hydroxy group. When only one of L and W includes hydroxy group, only mono-ester is possible. When both L and W include hydroxy, mono- and di-esters (which can be the same or different) can be made. Typical esters are simple alkanoate esters, such as acetate, propionate, butyrate, etc. In addition, when L or W includes a hydroxy group, bioprecursors can be made by converting the hydroxy group to an acyloxymethyl derivative (e.g., a pivaloyloxymethyl derivative) by reaction with an acyloxymethyl halide (e.g., pivaloyloxymethyl chloride).
[0176] When the compounds of the formula (I) of this invention may form solvates such as hydrates, such solvates are included within the scope of this invention.
[0177] Compounds of formula (I) containing one or more asymmetric carbon atoms can exist as two or more stereoisomers. Where a compound of formula (I) contains an alkenyl or alkenylene group, geometric cis/trans (or Z/E) isomers are possible. Where the compound contains, for example, a keto or oxime group or an aromatic moiety, tautomeric isomerism (‘tautomerism’) can occur. It follows that a single compound may exhibit more than one type of isomerism.
[0178] Included within the scope of the present invention are all stereoisomers, geometric isomers and tautomeric forms of the compounds of formula (I), including compounds exhibiting more than one type of isomerism, and mixtures of one or more thereof. Also included are acid addition or base salts wherein the counterion is optically active, for example, D-lactate or L-lysine, or racemic, for example, DL-tartrate or DL-arginine.
[0179] Cis/trans isomers may be separated by conventional techniques well known to those skilled in the art, for example, chromatography and fractional crystallisation.
[0180] Conventional techniques for the preparation/isolation of individual enantiomers include chiral synthesis from a suitable optically pure precursor or resolution of the racemate (or the racemate of a salt or derivative) using, for example, chiral high pressure liquid chromatography (HPLC).
[0181] Alternatively, the racemate (or a racemic precursor) may be reacted with a suitable optically active compound, for example, an alcohol, or, in the case where the compound of formula (I) contains an acidic or basic moiety, an acid or base such as tartaric acid or 1-phenylethylamine. The resulting diastereomeric mixture may be separated by chromatography and/or fractional crystallization and one or both of the diastereoisomers converted to the corresponding pure enantiomer(s) by means well known to a skilled person.
[0182] Stereoisomeric conglomerates may be separated by conventional techniques known to those skilled in the art—see, for example, “Stereochemistry of Organic Compounds” by E L Eliel (Wiley, New York, 1994).
[0183] Compounds of the invention intended for pharmaceutical use may be administered as crystalline or amorphous products. They may be obtained, for example, as solid plugs, powders, or films by methods such as precipitation, crystallization, freeze drying, spray drying, or evaporative drying. Microwave or radio frequency drying may be used for this purpose.
[0184] They may be administered alone or in combination with one or more other compounds of the invention or in combination with one or more other drugs (or as any combination thereof). Generally, they will be administered as a formulation in association with one or more pharmaceutically acceptable excipients. The term “excipient” is used herein to describe any ingredient other than the compound(s) of the invention. The choice of excipient will to a large extent depend on factors such as the particular mode of administration, the effect of the excipient on solubility and stability, and the nature of the dosage form.
[0185] Pharmaceutical compositions suitable for the delivery of compounds of the present invention and methods for their preparation will be readily apparent to those skilled in the art. Such compositions and methods for their preparation may be found, for example, in ‘Remington's Pharmaceutical Sciences’, 19th Edition (Mack Publishing Company, 1995).
[0000] Oral Administration
[0186] The compounds of the invention may be administered orally. Oral administration may involve swallowing, so that the compound enters the gastrointestinal tract, or buccal or sublingual administration may be employed by which the compound enters the blood stream directly from the mouth.
[0187] Formulations suitable for oral administration include solid formulations such as tablets, capsules containing particulates, liquids, or powders, lozenges (including liquid-filled), chews, multi- and nano-particulates, gels, solid solution, liposome, films (including muco-adhesive), ovules, sprays and liquid formulations.
[0188] Liquid formulations include suspensions, solutions, syrups and elixirs. Such formulations may be employed as fillers in soft or hard capsules and typically comprise a carrier, for example, water, ethanol, polyethylene glycol, propylene glycol, methylcellulose, or a suitable oil, and one or more emulsifying agents and/or suspending agents. Liquid formulations may also be prepared by the reconstitution of a solid, for example, from a sachet.
[0189] The compounds of the invention may also be used in fast-dissolving, fast-disintegrating dosage forms such as those described in Expert Opinion in Therapeutic Patents, 11 (6), 981-986 by Liang and Chen (2001).
[0190] For tablet dosage forms, depending on dose, the drug may make up from 1 wt % to 80 wt % of the dosage form, more typically from 5 wt % to 60 wt % of the dosage form. In addition to the drug, tablets generally contain a disintegrant. Examples of disintegrants include sodium starch glycolate, sodium carboxymethyl cellulose, calcium carboxymethyl cellulose, croscarmellose sodium, crospovidone, polyvinylpyrrolidone, methyl cellulose, microcrystalline cellulose, lower alkyl-substituted hydroxypropyl cellulose, starch, pregelatinised starch and sodium alginate. Generally, the disintegrant will comprise from 1 wt % to 25 wt %, preferably from 5 wt % to 20 wt % of the dosage form.
[0191] Binders are generally used to impart cohesive qualities to a tablet formulation. Suitable binders include microcrystalline cellulose, gelatin, sugars, polyethylene glycol, natural and synthetic gums, polyvinylpyrrolidone, pregelatinised starch, hydroxypropyl cellulose and hydroxypropyl methylcellulose. Tablets may also contain diluents, such as lactose (monohydrate, spray-dried monohydrate, anhydrous and the like), mannitol, xylitol, dextrose, sucrose, sorbitol, microcrystalline cellulose, starch and dibasic calcium phosphate dihydrate.
[0192] Tablets may also optionally comprise surface active agents, such as sodium lauryl sulfate and polysorbate 80, and glidants such as silicon dioxide and talc. When present, surface active agents may comprise from 0.2 wt % to 5 wt % of the tablet, and glidants may comprise from 0.2 wt % to 1 wt % of the tablet.
[0193] Tablets also generally contain lubricants such as magnesium stearate, calcium stearate, zinc stearate, sodium stearyl fumarate, and mixtures of magnesium stearate with sodium lauryl sulphate. Lubricants generally comprise from 0.25 wt % to 10 wt %, preferably from 0.5 wt % to 3 wt % of the tablet.
[0194] Other possible ingredients include anti-oxidants, colourants, flavouring agents, preservatives and taste-masking agents.
[0195] Exemplary tablets contain up to about 80% drug, from about 10 wt % to about 90 wt % binder, from about 0 wt % to about 85 wt % diluent, from about 2 wt % to about 10 wt % disintegrant, and from about 0.25 wt % to about 10 wt % lubricant.
[0196] Tablet blends may be compressed directly or by roller to form tablets. Tablet blends or portions of blends may alternatively be wet-, dry-, or melt-granulated, melt congealed, or extruded before tabletting. The final formulation may comprise one or more layers and may be coated or uncoated; it may even be encapsulated.
[0197] The formulation of tablets is discussed in “Pharmaceutical Dosage Forms: Tablets, Vol. 1”, by H. Lieberman and L. Lachman, Marcel Dekker, N.Y., N.Y., 1980 (ISBN 0-8247-6918-X).
[0198] Solid formulations for oral administration may be formulated to be immediate and/or modified release. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release.
[0199] Suitable modified release formulations for the purposes of the invention are described in U.S. Pat. No. 6,106,864. Details of other suitable release technologies such as high energy dispersions and osmotic and coated particles are to be found in Verma et al, Pharmaceutical Technology On-line, 25(2), 1-14 (2001). The use of chewing gum to achieve controlled release is described in WO 00/35298.
[0000] Parenteral Administration
[0200] The compounds of the invention may also be administered directly into the blood stream, into muscle, or into an internal organ. Suitable means for parenteral administration include intravenous, intraarterial, intraperitoneal, intrathecal, intraventricular, intraurethral, intrasternal, intracranial, intramuscular and subcutaneous. Suitable devices for parenteral administration include needle (including microneedle) injectors, needle-free injectors and infusion techniques.
[0201] Parenteral formulations are typically aqueous solutions which may contain excipients such as salts, carbohydrates and buffering agents (preferably to a pH of from 3 to 9), but, for some applications, they may be more suitably formulated as a sterile non-aqueous solution or as a dried form to be used in conjunction with a suitable vehicle such as sterile, pyrogen-free water.
[0202] The preparation of parenteral formulations under sterile conditions, for example, by lyophilisation, may readily be accomplished using standard pharmaceutical techniques well known to those skilled in the art.
[0203] The solubility of compounds of formula (I) used in the preparation of parenteral solutions may be increased by the use of appropriate formulation techniques, such as the incorporation of solubility-enhancing agents.
[0204] Formulations for parenteral administration may be formulated to be immediate and/or modified release. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release. Thus compounds of the invention may be formulated as a solid, semi-solid, or thixotropic liquid for administration as an implanted depot providing modified release of the active compound. Examples of such formulations include drug-coated stents and PGLA micro spheres.
[0000] Topical Administration
[0205] The compounds of the invention may also be administered topically to the skin or mucosa, that is, dermally or transdermally. Typical formulations for this purpose include gels, hydrogels, lotions, solutions, creams, ointments, dusting powders, dressings, foams, films, skin patches, wafers, implants, sponges, fibres, bandages and microemulsions. Liposomes may also be used. Typical carriers include alcohol, water, mineral oil, liquid petrolatum, white petrolatum, glycerin, polyethylene glycol and propylene glycol. Penetration enhancers may be incorporated—see, for example, J Pharm Sci, 88 (10), 955-958 by Finnin and Morgan (October 1999).
[0206] Other means of topical administration include delivery by electroporation, iontophoresis, phonophoresis, sonophoresis and microneedle or needle-free (e.g. Powderject™, Bioject™, etc.) injection.
[0207] Formulations for topical administration may be formulated to be immediate and/or modified release. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release.
[0000] Inhaled/Intranasal Administration
[0208] The compounds of the invention can also be administered intranasally or by inhalation, typically in the form of a dry powder (either alone, as a mixture, for example, in a dry blend with lactose, or as a mixed component particle, for example, mixed with phospholipids, such as phosphatidylcholine) from a dry powder inhaler or as an aerosol spray from a pressurised container, pump, spray, atomiser (preferably an atomiser using electrohydrodynamics to produce a fine mist), or nebuliser, with or without the use of a suitable propellant, such as 1,1,1,2-tetrafluoroethane or 1,1,1,2,3,3,3-heptafluoropropane. For intranasal use, the powder may comprise a bioadhesive agent, for example, chitosan or cyclodextrin.
[0209] The pressurised container, pump, spray, atomizer, or nebuliser contains a solution or suspension of the compound(s) of the invention comprising, for example, ethanol, aqueous ethanol, or a suitable alternative agent for dispersing, solubilising, or extending release of the active, a propellant(s) as solvent and an optional surfactant, such as sorbitan trioleate, oleic acid, or an oligolactic acid.
[0210] Prior to use in a dry powder or suspension formulation, the drug product is micronised to a size suitable for delivery by inhalation (typically less than 5 microns). This may be achieved by any appropriate comminuting method, such as spiral jet milling, fluid bed jet milling, supercritical fluid processing to form nanoparticles, high pressure homogenisation, or spray drying.
[0211] Capsules (made, for example, from gelatin or HPMC), blisters and cartridges for use in an inhaler or insufflator may be formulated to contain a powder mix of the compound of the invention, a suitable powder base such as lactose or starch and a performance modifier such as l-leucine, mannitol, or magnesium stearate. The lactose may be anhydrous or in the form of the monohydrate, preferably the latter. Other suitable excipients include dextran, glucose, maltose, sorbitol, xylitol, fructose, sucrose and trehalose.
[0212] A suitable solution formulation for use in an atomiser using electrohydrodynamics to produce a fine mist may contain from 1 μg to 20 mg of the compound of the invention per actuation and the actuation volume may vary from 1 μl to 100 μl. A typical formulation may comprise a compound of formula (I), propylene glycol, sterile water, ethanol and sodium chloride. Alternative solvents which may be used instead of propylene glycol include glycerol and polyethylene glycol.
[0213] Suitable flavours, such as menthol and levomenthol, or sweeteners, such as saccharin or saccharin sodium, may be added to those formulations of the invention intended for inhaled/intranasal administration.
[0214] Formulations for inhaled/intranasal administration may be formulated to be immediate and/or modified release using, for example, poly(DL-lactic-coglycolic acid (PGLA). Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release.
[0215] In the case of dry powder inhalers and aerosols, the dosage unit is determined by means of a valve which delivers a metered amount. Units in accordance with the invention are typically arranged to administer a metered dose or “puff” containing from 1 to 100 μg of the compound of formula (I). The overall daily dose will typically be in the range 50 μg to 20 mg which may be administered in a single dose or, more usually, as divided doses throughout the day.
[0000] Rectal/Intravaginal Administration
[0216] The compounds of the invention may be administered rectally or vaginally, for example, in the form of a suppository, pessary, or enema. Cocoa butter is a traditional suppository base, but various alternatives may be used as appropriate.
[0217] Formulations for rectal/vaginal administration may be formulated to be immediate and/or modified release. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted and programmed release.
[0000] Ocular/Aural Administration
[0218] The compounds of the invention may also be administered directly to the eye or ear, typically in the form of drops of a micronised suspension or solution in isotonic, pH-adjusted, sterile saline. Other formulations suitable for ocular and aural administration include ointments, biodegradable (e.g. absorbable gel sponges, collagen) and non-biodegradable (e.g. silicone) implants, wafers, lenses and particulate or vesicular systems, such as niosomes or liposomes. A polymer such as crossed-linked polyacrylic acid, polyvinylalcohol, hyaluronic acid, a cellulosic polymer, for example, hydroxypropylmethylcellulose, hydroxyethylcellulose, or methyl cellulose, or a heteropolysaccharide polymer, for example, gelan gum, may be incorporated together with a preservative, such as benzalkonium chloride. Such formulations may also be delivered by iontophoresis.
[0219] Formulations for ocular/aural administration may be formulated to be immediate and/or modified release. Modified release formulations include delayed-, sustained-, pulsed-, controlled-, targeted, or programmed release.
[0000] Other Technologies
[0220] The compounds of the invention may be combined with soluble macromolecular entities, such as cyclodextrin and suitable derivatives thereof or polyethylene glycol-containing polymers, in order to improve their solubility, dissolution rate, taste-masking, bioavailability and/or stability for use in any of the aforementioned modes of administration.
[0221] Drug-cyclodextrin complexes, for example, are found to be generally useful for most dosage forms and administration routes. Both inclusion and non-inclusion complexes may be used. As an alternative to direct complexation with the drug, the cyclodextrin may be used as an auxiliary additive, i.e. as a carrier, diluent, or solubiliser. Most commonly used for these purposes are alpha-, beta- and gamma-cyclodextrins, examples of which may be found in International Patent Applications Nos. WO 91/11172, WO 94/02518 and WO 98/55148.
[0000] Kit-of-Parts
[0222] Inasmuch as it may desirable to administer a combination of active compounds, for example, for the purpose of treating a particular disease or condition, it is within the scope of the present invention that two or more pharmaceutical compositions, at least one of which contains a compound in accordance with the invention, may conveniently be combined in the form of a kit suitable for coadministration of the compositions.
[0223] Thus the kit of the invention comprises two or more separate pharmaceutical compositions, at least one of which contains a compound of formula (I) in accordance with the invention, and means for separately retaining said compositions, such as a container, divided bottle, or divided foil packet. An example of such a kit is the familiar blister pack used for the packaging of tablets, capsules and the like.
[0224] The kit of the invention is particularly suitable for administering different dosage forms, for example, oral and parenteral, for administering the separate compositions at different dosage intervals, or for titrating the separate compositions against one another. To assist compliance, the kit typically comprises directions for administration and may be provided with a so-called memory aid.
[0000] Dosage
[0225] For administration to human patients, the total daily dose of the compounds of the invention is typically in the range 0.05 mg to 100 mg depending, of course, on the mode of administration, preferred in the range 0.1 mg to 50 mg and more preferred in the range 0.5 mg to 20 mg. For example, oral administration may require a total daily dose of from 1 mg to 20 mg, while an intravenous dose may only require from 0.5 mg to 10 mg. The total daily dose may be administered in single or divided doses.
[0226] These dosages are based on an average human subject having a weight of about 65 kg to 70 kg. The physician will readily be able to determine doses for subjects whose weight falls outside this range, such as infants and the elderly.
[0227] For the avoidance of doubt, references herein to “treatment” include references to curative, palliative and prophylactic treatment.
[0228] A 5-HT 4 agonist of the present invention may be usefully combined with another pharmacologically active compound, or with two or more other pharmacologically active compounds, particularly in the treatment of gastroesophageal reflux disease. For example, a 5-HT 4 agonist, particularly a compound of the formula (I), or a pharmaceutically acceptable salt or solvate thereof, as defined above, may be administered simultaneously, sequentially or separately in combination with one or more agents selected from:
(i) histamine H 2 receptor antagonists, e.g. ranitidine, lafutidine, nizatidine, cimetidine, famotidine and roxatidine; (ii) proton pump inhibitors, e.g. omeprazole, esomeprazole, pantoprazole, rabeprazole, tenatoprazole, ilaprazole and lansoprazole; (iii) Acid pump antagonists, e.g. soraprazan, revaprazan(YH-1885), AZD-0865, CS-526, AU-2064 and YJA-20379-8; (iv) oral antacid mixtures, e.g. Maalox®, Aludrox® and Gaviscon®; (v) mucosal protective agents, e.g. polaprezinc, ecabet sodium, rebamipide, teprenone, cetraxate, sucralfate, chloropylline-copper and plaunotol; (vi) GABAB agonists, e.g. baclofen and AZD-3355; (vii) α2 agonists, e.g. clonidine, medetomidine, lofexidine, moxonidine, tizanidine, guanfacine, guanabnz, talipexole and dexmedetomidine; (viii) Xanthin derivatives, e.g. Theophylline, aminophylline and doxofylline; (ix) calcium channel blockers, e.g. aranidipine, lacidipine, falodipine, azelnidipine, clinidipine, lomerizine, diltiazem, gallopamil, efonidipine, nisoldipine, amlodipine, lercanidipine, bevantolol, nicardipine, isradipine, benidipine, verapamil, nitrendipine, barnidipine, propafenone, manidipine, bepridil, nifedipine, nilvadipine, nimodipine, nifedipine and fasudil; (x) benzodiazepine agonists, e.g. diazepam, zaleplon, zolpidem, haloxazolam, clonazepam, prazepam, quazepam, flutazolam, triazolam, lormetazepam, midazolam, tofisopam, clobazam, flunitrazepam and flutoprazepam; (xi) prostaglandin analogues, e.g. Prostaglandin, misoprostol, treprostinil, esoprostenol, latanoprost, iloprost, beraprost, enprostil, ibudilast and ozagrel; (xii) histamine H 3 agonists, e.g. R-alpha-methylhistamine and BP-294; (xiii) anti-gastric agents, e.g. Anti-gastrin vaccine, itriglumide and Z-360; (xiv) 5-HT 3 antagonists, e.g. dolasetron, palonosetron, alosetron, azasetron, ramosetron, mitrazapine, granisetron, tropisetron, E-3620, ondansetron and indisetron; (xv) tricyclic antidepressants, e.g. imipramine, amitriptyline, clomipramine, amoxapine and lofepramine; (xvi) GABA agonists, e.g. gabapentin, topiramate, cinolazepam, clonazepam, progabide, brotizolam, zopiclone, pregabalin and eszopiclone; (xvii) opioid analgesics, e.g. morphine, heroin, hydromorphone, oxymorphone, levorphanol, levallorphan, methadone, meperidine, fentanyl, cocaine, codeine, dihydrocodeine, oxycodone, hydrocodone, propoxyphene, nalmefene, nalorphine, naloxone, naltrexone, buprenorphine, butorphanol, nalbuphine and pentazocine; (xviii) somatostatin analogues, e.g. octreotide, AN-238 and PTR-3173; (xix) Cl Channel activator: e.g. lubiprostone; (xx) selective serotonin reuptake inhibitors, e.g. sertraline, escitalopram, fluoxetine, nefazodone, fluvoxamine, citalopram, milnacipran, paroxetine, venlafaxine, tramadol, sibutramine, duloxetine, desvenlafaxine and depocxetine; (xxi) anticholinergics, e.g. dicyclomine and hyoscyamine; (xxii) laxatives, e.g. Trifyba®, Fybogel®, Konsyl®, Isogel®, Regulan®, Celevac® and Normacol®; (xxiii) fiber products, e.g. Metamucil®; (xxiv) antispasmodics, e.g.: mebeverine; (xxv) dopamine antagonists, e.g. metoclopramide, domperidone and levosulpiride; (xxvi) cholinergics, e.g. neostigmine (xxvii) AChE inhibitor: galantamine, metrifonate, rivastigmine, itopride and donepezil; (xxviii) Tachykinin (NK) antagonists, particularly NK-3, NK-2 and NK-1 e.g. antagonists, nepadutant, saredutant, talnetant, (αR,9R)-7-[3,5-bis(trifluoromethyl)benzyl]-8,9,10,11-tetrahydro-9-methyl-5-(4-methylphenyl)-7H-[1,4]diazocino[2,1-g][1,7]naphthridine-6-13-dione (TAK-637), 5-[[(2R,3S)-2-[(1R)-1-[3,5-bis(trifluoromethyl)phenyl]ethoxy-3-(4-fluorophenyl)-4-morpholinyl]methyl]-1,2-dihydro-3H-1,2,4-triazol-3-one (MK-869), lanepitant, dapitant and 3-[[2-methoxy-5-(trifluoromethoxy)phenyl]methylamino]-2-phenyl-piperidine (2S,3S).
Method for Assessing Biological Activities:
[0257] The 5-HT 4 receptor binding affinities of the compounds of this invention are determined by the following procedures.
[0000] Membrane Preparation
[0258] Pig heads were supplied from an abattoir. Striatal tissues were dissected, weighed and homogenized in 15 volumes of 50 mM ice-cold HEPES (pH 7.5) in a Polytron homogenizer (30 sec at full speed). Suspension was centrifuged at 48,000 g and 4° C. for 15 min. The resulting pellet was resuspended in an appropriate volume of 50 mM ice-cold HEPES, dispensed into aliquots and stored at −80° C. until use.
[0259] Bovine heads were also supplied from an abattoir. Striatal tissues were dissected, weighed and homogenized in 20 volumes of 50 mM ice-cold Tris-HCl (pH 7.4) in a Polytron homogenizer (30 sec at full speed). Suspension was centrifuged at 20,000 g and 4° C. for 30 min. The resulting pellet was resuspended in 15 volumes of 50 mM ice-cold Tris-HCl, homegenized and centrifuged again in the same way. The final pellet was resuspended in an appropriate volume of 50 mM Tris-HCl, dispensed into aliquots and stored at −80° C. until use.
[0260] Cerebral cortical tissues were removed from male Sprague-Dawley (SD) rats (Japan SLC), weighed and placed in 10 volumes of 50 mM ice-cold Tris-HCl (pH 7.5). This was homogenized in a Polytron homogenizer (30 sec at full speed) and subsequently centrifuged at 48,000 g and 4° C. for 15 min. The resulting pellet was resuspended in 50 mM ice-cold Tris-HCl, homegenized and centrifuged again in the same way. The final pellet was resuspended in an appropriate volume of 50 mM Tris-HCl, dispensed into aliquots and stored at −80° C. until use.
[0261] The protein concentrations of homogenates were determined by Bradford method or BCA protein method (Pierce) with BSA as a standard.
[0000] Binding Assays
[0262] Affinity of compounds for pig or bovine 5-HT 4 and rat 5-HT 3 receptors were assessed with using radiolabeled specific ligands, GR 113808 ({1-[2-(methylsulfonyl)ethyl]-4-piperidinyl}[methyl-3H]-1H-indole-3-carboxylate) and BRL 43694 (1-Methyl-N-(9-[methyl-3H]-9-azabicyclo[3.3.1]non-3-yl)-1H-indazole-3-caboxamide). Compounds were incubated with 25-100 pM of [ 3 H]-GR 113808 (Amersham) and 0.6-1 mg protein of pig or bovine striatal membranes suspended in a final volume of 0.8-1 ml of 50 mM Tris-HCl (pH 7.5). Nonspecific binding was determined with 10-50 μM 5-HT. The binding of 0.3 nM [ 3 H]-BRL 43694 (NEN) was measured using 400 μg protein of rat cortical membranes suspended in a final volume of 500 μl of 50 mM Tris-HCl (pH 7.5). Nonspecific binding was determined with 10 μM 5-HT.
[0263] The plates were incubated at room temperature on a plate shaker for 30 min. The assays were stopped by rapid filtration using a Brandell cell harvester through Wallac-B filters pre-soaked in 0.2% poly(ethylenimine) at 4° C. for 60-90 min. The filters were washed three times with 1 ml of ice-cold 50 mM HEPES, and were dried in a microwave or at room temperature. They were bagged and heated with meltilex scintillant (Wallac) or soaked in BetaplateScint (Wallac). Receptor-bound radioactivity was quantified using Big-spot counter, Betaplate counter (Wallac) or LS counter (Packard).
[0000] Human 5-HT 4 Binding(1)
[0264] Human 5-HT 4(d) transfected HEK293 cells were prepared and grown in-house. The collected cells were suspended in 50 mM HEPES (pH 7.4 at 4° C.) supplemented with protease inhibitor cocktail (Boehringer, 1:1000 dilution) and homogenized using a hand held Polytron PT 1200 disruptor set at full power for 30 sec on ice. The homogenates were centrifuged at 40,000×g at 4° C. for 30 min. The pellets were then resuspended in 50 mM HEPES (pH 7.4 at 4° C.) and centrifuged once more in the same manner. The final pellets were resuspended in an appropriate volume of 50 mM HEPES (pH 7.4 at 25° C.), homogenized, aliquoted and stored at −80° C. until use. An aliquot of membrane fractions was used for protein concentration determination using BCA protein assay kit (PIERCE) and ARVOsx plate reader (Wallac).
[0265] For the binding experiments, 25 μl of test compounds were incubated with 25 μl of [ 3 H]-GR113808 (Amersham, final 0.2 nM) and 150 μl of membrane homogenate and WGA-SPA beads (Amersham) suspension solutions (10 μg protein and 1 mg SPA beads/well) for 60 minutes at room temperature. Nonspecific binding was determined by 1 μM GR113808 (Tocris) at the final concentration. Incubation was terminated by centrifugation at 1000 rpm. Receptor-bound radioactivity was quantified by counting with MicroBeta plate counter (Wallac).
[0266] All compounds prepared in the working examples as described below were tested by this method, and they showed Ki values from 0.3 nM to 30 nM with respect to inhibition of binding at the 5-HT 4 receptor.
[0000] Human 5-HT 4 Binding(2)
[0267] Human 5-HT 4(d) transfected HEK293 cells were prepared and grown in-house. The collected cells were suspended in 50 mM Tris buffer (pH 7.4 at 4° C.) supplemented with protease inhibitor cocktail (Boehringer, 1:1000 dilution) and homogenized using a hand held Polytron PT 1200 disruptor set at full power for 30 sec on ice. The homogenates were centrifuged at 40,000×g at 4° C. for 10 min. The pellets were then resuspended in 50 mM Tris buffer (pH 7.4 at 4° C.) and centrifuged once more in the same manner. The final pellets were resuspended in an appropriate volume of 50 mM Tris buffer (pH 7.4 at 25° C.) containing 10 mM MgCl 2 , homogenized, aliquoted and stored at −80° C. until use. An aliquot of membrane fractions was used for protein concentration determination using BCA protein assay kit (PIERCE) and ARVOsx plate reader (Wallac). For the binding experiments, 50 μl of test compounds were incubated with 50 μl of [ 3 H] 5-HT (Amersham, final 8.0 nM) and 400 μl of membrane homogenate (300 μg protein/tube) for 60 minutes at room temperature. Nonspecific binding was determined by 50 μM GR113808 (Tocris) at the final concentration. All incubations were terminated by rapid vacuum filtration over 0.2% PEI soaked glass fiber filter papers using BRANDEL harvester followed by three washes with 50 mM Tris buffer (pH 7.4 at 25° C.). Receptor-bound radioactivity was quantified by liquid scintillation counting using Packard LS counter.
[0268] All compounds of Examples showed 5HT 4 receptor affinity.
[0000] Functional Assay:
[0269] The presence of 5-HT 4 receptors in the rat oesophagus and the ability to demonstrate partial agonism in the TMM preparation are reported in the literature (See G. S. Baxter et al. Naunyn-Schmiedeberg's Arch Pharmacol (1991) 343: 439-446; M. Yukiko et al. JPET (1997) 283: 1000-1008; and J. J. Reeves et al. Br. J. Pharmacol. (1991) 103: 1067-1072). More specifically, partial agonist activity can be measured according to the following procedures.
[0270] Male SD rats (Charles River) weighing 250-350 g were stunned and then killed by cervical dislocation. The oesophagus was dissected from immediately proximal to the stomach (including piece of stomach to mark distal end) up to the level of the trachea and then placed in fresh Krebs' solution.
[0271] The outer skeletal muscle layer was removed in one go by peeling it away from the underlying smooth muscle layer using forceps (stomach to tracheal direction). The remaining inner tube of smooth muscle was known as the TMM. This was trimmed to 2 cm from the original ‘stomach-end’ and the rest discarded.
[0272] The TMMs were mounted as whole ‘open’ tubes in longitudinal orientation in 5 ml organ baths filled with warm (32° C.) aerated Krebs. Tissues were placed under an initial tension of 750 mg and allowed to equilibrate for 60 minutes. The tissues were re-tensioned twice at 15 minute intervals during the equilibration period. The pump flow rate was set to 2 ml/min during this time.
[0273] Following equilibration, the pump was switched off. The tissues were exposed to 1 μM carbachol and contracted and reached a steady contractile plateau within 15 minutes. Tissues were then subject to 1 μM 5-HT (this was to prime the tissues). The tissues relaxed in response to 5-HT fairly rapidly—within 1 minute. As soon as maximal relaxation has occurred and a measurement taken, the tissues were washed at maximum rate (66 ml/min) for at least 1 minute and until the original baseline (pre-carbachol and 5-HT) has returned (usually, the baseline drops below the original one following initial equilibration). The pump flow rate was reduced to 2 ml/min and the tissues left for 60 minutes.
[0274] A cumulative concentration-effect-curve (CEC) to 5-HT was constructed across the range 0.1 nM to 1 μM, in half-log unit increments (5-HT curve 1 for data analysis). Contact time between doses was 3 minutes or until plateau established. Tissues responded quicker as concentration of 5-HT in the bath increases. At the end of the curve, the tissues were washed (at maximum rate) as soon as possible to avoid desensitisation of receptors. Pump rate was reduced to 2 ml/min and the tissues left for 60 minutes.
[0275] A second CEC was carried out—either to 5-HT (for time control tissues), another 5-HT 4 agonist (standard) or a test compound (curve 2 for data analysis). Contact time varied for other 5-HT 4 agonists and test compounds and was tailored according to the tissues' individual responses to each particular agent. In tissues exposed to a test compound, a high concentration (1 μm) of a 5-HT 4 antagonist (SB 203,186: 1H-Indole-3-carboxylic acid, 2-(1-piperidinyl)ethyl ester, Tocris) was added to the bath following the last concentration of test compound. This was to see if any agonist-induced relaxation (if present) could be reversed. SB 203,186 reversed 5-HT induced relaxation, restoring the tissue's original degree of carbachol-induced tone.
[0276] Agonist activity of test compounds was confirmed by pre-incubating tissues with 100 nM standard 5HT 4 antagonist such as SB 203,186. SB 203,186 was added to the bath 5 minutes before the addition of carbachol prior to curve 2. Tissues must be ‘paired’ for data analysis i.e. the test compound in the absence of SB 203,186 in one tissue was compared with the test compound in the presence of SB 203,186 in a separate tissue. It was not possible to carry out a curve 3 i.e. 5-HT curve 1, followed by the test compound curve 2 (−SB 203,186), followed by the test compound curve 3 (+SB 203,186).
[0000] Agonist-Induced cAMP Elevation in Human 5-HT 4(d) Transfected HEK293 Cells
[0277] Human S-HT 4(d) transfected HEK293 cells were established in-house. The cells were grown at 37° C. and 5% CO 2 in DMEM supplemented with 10% FCS, 20 mM HEPES (pH 7.4), 200 μg/ml hygromycin B (Gibco), 100 units/ml penicillin and 100 μg/ml streptomycin.
[0278] The cells were grown to 60-80% confluence. On the previous day before treatment with compounds dialyzed FCS (Gibco) was substituted for normal and the cells were incubated overnight.
[0279] Compounds were prepared in 96-well plates (12.5 μl/well). The cells were harvested with PBS/1 mM EDTA, centrifuged and washed with PBS. At the beginning of the assay, cell pellet was resuspended in DMEM supplemented with 20 mM HEPES, 10 μM pargyline (Sigma) and 1 mM 3-isobutyl-1-methylxanthine (Sigma) at the concentration of 1.6×10 5 cells/ml and left for 15 minutes at room temperature. The reaction was initiated by addition of the cells into plates (12.5 μl/well). After incubation for 15 minutes at room temperature, 1% Triton X-100 was added to stop the reaction (25 μl/well) and the plates were left for 30 minutes at room temperature. Homogenous time-resolved fluorescence-based cAMP (Schering) detection was made according to the manufacturer's instruction. ARVOsx multilabel counter (Wallac) was used to measure HTRF (excitation 320 nm, emission 665 nm/620 nm, delay time 50 μs, window time 400 μs).
[0280] Data was analyzed based on the ratio of fluorescence intensity of each well at 620 nm and 665 nm followed by cAMP quantification using cAMP standard curve. Enhancement of cAMP production elicited by each compound was normalized to the amount of cAMP produced by 1000 nM serotonin (Sigma).
[0281] All compounds of Examples showed 5HT 4 receptor agonistic activity.
[0000] Human Dofetilide Binding
[0282] Human HERG transfected HEK293S cells were prepared and grown in-house. The collected cells were suspended in 50 mM Tris-HCl (pH 7.4 at 4° C.) and homogenized using a hand held Polytron PT 1200 disruptor set at full power for 20 sec on ice. The homogenates were centrifuged at 48,000×g at 4° C. for 20 min. The pellets were then resuspended, homogenized, and centrifuged once more in the same manner. The final pellets were resuspended in an appropriate volume of 50 mM Tris-HCl, 10 mM KCl, 1 mM MgCl 2 (pH 7.4 at 4° C.), homogenized, aliquoted and stored at −80° C. until use. An aliquot of membrane fractions was used for protein concentration determination using BCA protein assay kit (PIERCE) and ARVOsx plate reader (Wallac).
[0283] Binding assays were conducted in a total volume of 200 μl in 96-well plates. Twenty μl of test compounds were incubated with 20 μl of [ 3 H]-dofetilide (Amersham, final 5 nM) and 160 μl of membrane homogenate (25 μg protein) for 60 minutes at room temperature. Nonspecific binding was determined by 10 μM dofetilide at the final concentration. Incubation was terminated by rapid vacuum filtration over 0.5% presoaked GF/B Betaplate filter using Skatron cell harvester with 50 mM Tris-HCl, 10 mM KCl, 1 mM MgCl 2 , pH 7.4 at 4° C. The filters were dried, put into sample bags and filled with Betaplate Scint. Radioactivity bound to filter was counted with Wallac Betaplate counter.
[0000] I HERG Assay
[0284] HEK 293 cells which stably express the HERG potassium channel were used for electrophysiological study. The methodology for stable transfection of this channel in HEK cells can be found elsewhere (Z. Zhou et al., 1998, Biophysical journal, 74, pp 230-241). Before the day of experimentation, the cells were harvested from culture flasks and plated onto glass coverslips in a standard MEM medium with 10% FCS. The plated cells were stored in an incubator at 37° C. maintained in an atmosphere of 95% O 2 /5% CO 2 . Cells were studied between 15-28 hrs after harvest.
[0285] HERG currents were studied using standard patch clamp techniques in the whole-cell mode. During the experiment the cells were superfused with a standard external solution of the following composition (mM); NaCl, 130; KCl, 4; CaCl 2 , 2; MgCl 2 , 1; Glucose, 10; HEPES, 5; pH 7.4 with NaOH. Whole-cell recordings was made using a patch clamp amplifier and patch pipettes which have a resistance of 1-3 MOhm when filled with the standard internal solution of the following composition (mM); KCl, 130; MgATP, 5; MgCl 2 , 1.0; HEPES, 10; EGTA 5, pH 7.2 with KOH. Only those cells with access resistances below 15 MΩ and seal resistances >1 GΩ was accepted for further experimentation. Series resistance compensation was applied up to a maximum of 80%. No leak subtraction was done. However, acceptable access resistance depended on the size of the recorded currents and the level of series resistance compensation that can safely be used. Following the achievement of whole cell configuration and sufficient for cell dialysis with pipette solution (>5 min), a standard voltage protocol was applied to the cell to evoke membrane currents. The voltage protocol is as follows. The membrane was depolarized from a holding potential of −80 mV to +20 mV for 1000 ms. This was followed by a descending voltage ramp (rate 0.5 mV msec −1 ) back to the holding potential. The voltage protocol was applied to a cell continuously throughout the experiment every 4 seconds (0.25 Hz). The amplitude of the peak current elicited around −40 mV during the ramp was measured. Once stable evoked current responses were obtained in the external solution, vehicle (0.5% DMSO in the standard external solution) was applied for 10-20 min by a peristalic pump. Provided there were minimal changes in the amplitude of the evoked current response in the vehicle control condition, the test compound of either 0.3, 1, 3, 10 μM was applied for a 10 min period. The 10 min period included the time which supplying solution was passing through the tube from solution reservoir to the recording chamber via the pump. Exposing time of cells to the compound solution was more than 5 min after the drug concentration in the chamber well reached the attempting concentration. There reversibility. Finally, the cells was exposed to high dose of dofetilide (5 μM), a specific IKr blocker, to evaluate the insensitive endogenous current.
[0286] All experiments were performed at room temperature (23±1° C.). Evoked membrane currents were recorded on-line on a computer, filtered at 500-1 KHz (Bessel −3 dB) and sampled at 1-2 KHz using the patch clamp amplifier and a specific data analyzing software. Peak current amplitude, which occurred at around −40 mV, was measured off line on the computer.
[0287] The arithmetic mean of the ten values of amplitude was calculated under control conditions and in the presence of drug. Percent decrease of I N in each experiment was obtained by the normalized current value using the following formula: I N =(1−I D /I C )×100, where I D is the mean current value in the presence of drug and I C is the mean current value under control conditions. Separate experiments were performed for each drug concentration or time-matched control, and arithmetic mean in each experiment is defined as the result of the study.
[0000] Half-Life in Human Liver Microsomes (HLM)
[0288] Test compounds (1 μM) were incubated with 3.3 mM MgCl 2 and 0.78 mg/mL HLM (HL101) in 100 mM potassium phosphate buffer (pH 7.4) at 37° C. on the 96-deep well plate. The reaction mixture was split into two groups, a non-P450 and a P450 group. NADPH was only added to the reaction mixture of the P450 group. An aliquot of samples of P450 group was collected at 0, 10, 30, and 60 min time point, where 0 min time point indicated the time when NADPH was added into the reaction mixture of P450 group. An aliquot of samples of non-P450 group was collected at −10 and 65 min time point. Collected aliquots were extracted with acetonitrile solution containing an internal standard. The precipitated protein was spun down in centrifuge (2000 rpm, 15 min). The compound concentration in supernatant was measured by LC/MS/MS system.
[0289] The half-life value was obtained by plotting the natural logarithm of the peak area ratio of compounds/internal standard versus time. The slope of the line of best fit through the points yields the rate of metabolism (k). This was converted to a half-life value using following equations:
Half-life=ln 2/ k
Method of Gastric Emptying Model in Rats:
[0290] The effects of compounds on gastric emptying in rats were examined by the modified method of D. A. Droppleman et al. (J. Pharmacol. Methods 4, 227-230 (1980)). The test meal, non-fat caloric meal, was prepared according to the method of S. Ueki et al Arzneim.-Forsch./Drug Res. 49 (II), 618-625 (1999)). IGS-SD rats (Male, 7w, 230-270 g) were purchased from Charles River Japan (Atsugi). These rats were used in the experiments after one week acclimatization. In the experiments, rats were fasted 15 hrs before the experiments but allowed free access to water. Forty-five minutes prior to the start of the experiment, water was removed from the cage to prevent rats from taking water. Five minutes before the test meal administration, test compounds, cisapride or vehicle were dosed via an appropriate route to rats (n=8-10) in a volume of 0.1 ml per 100 g body weight. Cisapride (3 mg/kg) was used as a positive control for the experiment. Rats were given 3 ml of the test meal by gavage and were returned to the cages. Thirty minutes after the meal administration, rats were culled by CO 2 exposure. Following a midline laparotomy, the stomach is ligated at the lower esophageal sphincter (LES) and pylorus. Then the stomach was removed and weighed (A). After the stomach was opened and rinsed with 0.9% saline, it was blotted the face with the tissue to remove any excess liquid and weighed again (B). After avoiding the rats that had eaten feces or given artificial miss, gastric emptying rate for individual animals was calculated by the formula:
GE rate (%)=( A−B )/weight of the test meal.
Gastric Motility in Conscious Dogs:
[0291] The surgical operation in dogs was performed by the modified method of Z. Itoh et al. (Gastroenterol. Jpn., 12, 275-283 (1977)). The effects of test compounds on gastric motility in dogs were examined by the modified method of N. Toshida et al. (J. Pharmacol. Exp/Ther., 257, 781-787 (1991)).
[0292] An evaluation in the fasted state: Animals were chronically implanted with a strain gauge force transducer on the gastric body, and fasted overnight prior to the experiment. The gastric motility was continuously recorded by a telemetry system for 8 h after administration of the compound. To quantitate the change in gastrointestinal motility, the motor index was determined as the area under the contraction curves during each 2 h period divided by the peak height of interdigestive migrating contraction.
[0293] An evaluation in the postprandial state: Animals were chronically implanted with a strain gauge force transducer on the gastric body, and fasted overnight prior to the experiment. Postprandial motility was induced by feeding with solid meal (100 grams), and the compound was administered 2 h later. The gastric motility was continuously recorded by a telemetry system for 8 h after administration of the compound. The motor index was determined to quantitate the change in gastrointestinal motility as the area under the contraction curves during each 1 h period divided by the area under the contraction curves for 1 h before the compound administration.
[0294] The compounds of formula (I) of this invention can be administered via either the oral, parenteral or topical routes to mammals. In general, these compounds are most desirably administered to humans in doses ranging from 0.3 mg to 750 mg per day, preferably from 10 mg to 500 mg per day, although variations will necessarily occur depending upon the weight and condition of the subject being treated, the disease state being treated and the particular route of administration chosen. However, for example, a dosage level that is in the range of from 0.06 mg to 2 mg per kg of body weight per day is most desirably employed for treatment of inflammation.
[0295] The compounds of the present invention may be administered alone or in combination with pharmaceutically acceptable carriers or diluents by either of the above routes previously indicated, and such administration can be carried out in single or multiple doses. More particularly, the novel therapeutic agents of the invention can be administered in a wide variety of different dosage forms, i.e., they may be combined with various pharmaceutically acceptable inert carriers in the form of tablets, capsules, lozenges, troches, hard candies, powders, sprays, creams, salves, suppositories, jellies, gels, pastes, lotions, ointments, aqueous suspensions, injectable solutions, elixirs, syrups, and the like. Such carriers include solid diluents or fillers, sterile aqueous media and various non-toxic organic solvents, etc. Moreover, oral pharmaceutical compositions can be suitably sweetened and/or flavored. In general, the therapeutically-effective compounds of this invention are present in such dosage forms at concentration levels ranging 5% to 70% by weight, preferably 10% to 50% by weight.
[0296] For oral administration, tablets containing various excipients such as microcrystalline cellulose, sodium citrate, calcium carbonate, dipotassium phosphate and glycine may be employed along with various disintegrants such as starch and preferably corn, potato or tapioca starch, alginic acid and certain complex silicates, together with granulation binders like polyvinylpyrrolidone, sucrose, gelatin and acacia. Additionally, lubricating agents such as magnesium stearate, sodium lauryl sulfate and talc are often very useful for tabletting purposes. Solid compositions of a similar type may also be employed as fillers in gelatin capsules; preferred materials in this connection also include lactose or milk sugar as well as high molecular weight polyethylene glycols. When aqueous suspensions and/or elixirs are desired for oral administration, the active ingredient may be combined with various sweetening or flavoring agents, coloring matter or dyes, and, if so desired, emulsifying and/or suspending agents as well, together with such diluents as water, ethanol, propylene glycol, glycerin and various like combinations thereof.
[0297] For parenteral administration, solutions of a compound of the present invention in either sesame or peanut oil or in aqueous propylene glycol may be employed. The aqueous solutions should be suitably buffered (preferably pH>8) if necessary and the liquid diluent first rendered isotonic. These aqueous solutions are suitable for intravenous injection purposes. The oily solutions are suitable for intra-articular, intramuscular and subcutaneous injection purposes. The preparation of all these solutions under sterile conditions is readily accomplished by standard pharmaceutical techniques well known to those skilled in the art. Additionally, it is also possible to administer the compounds of the present invention topically when treating inflammatory conditions of the skin and this may preferably be done by way of creams, jellies, gels, pastes, ointments and the like, in accordance with standard pharmaceutical practice.
EXAMPLES
[0298] The invention is illustrated in the following non-limiting examples in which, unless stated otherwise: all operations were carried out at room or ambient temperature, that is, in the range of 18-25° C.; evaporation of solvent was carried out using a rotary evaporator under reduced pressure with a bath temperature of up to 60° C.; reactions were monitored by thin layer chromatography (tlc) and reaction times are given for illustration only; melting points (m.p.) given are uncorrected (polymorphism may result in different melting points); the structure and purity of all isolated compounds were assured by at least one of the following techniques: tlc (Merck silica gel 60 F 254 precoated TLC plates or Merck NH 2 F 254 , precoated HPTLC plates), mass spectrometry, nuclear magnetic resonance (NMR), infrared red absorption spectra (IR), microanalysis or powder X-ray diffraction (PXRD) pattern. Yields are given for illustrative purposes only. Flash column chromatography was carried out using Merck silica gel 60 (230-400 mesh ASTM) or Fuji Silysia Chromatorex® DU3050 (Amino Type, 30˜50 μm). Low-resolution mass spectral data (EI) were obtained on a Integrity (Waters) mass spectrometer or a Automass 120 (JEOL) mass spectrometer. Low-resolution mass spectral data (ESI) were obtained on a ZMD2 (Waters) mass spectrometer or a Quattro II (Micromass) mass spectrometer. NMR data was determined at 270 MHz (JEOL JNM-LA 270 spectrometer) or 300 MHz (JEOL JNM-LA300) using deuterated chloroform (99.8% D) or dimethylsulfoxide (99.9% D) as solvent unless indicated otherwise, relative to tetramethylsilane (TMS) as internal standard in parts per million (ppm); conventional abbreviations used are: s=singlet, d=doublet, t=triplet, q=quartet, m=multiplet, br.=broad, etc. IR spectra were measured by a Shimazu infrared spectrometer (IR-470). Optical rotations were measured using a JASCO DIP-370 Digital Polarimeter (Japan Spectroscopic CO, Ltd.). PXRD pattern was determined using a Rigaku RINT-TTR powder X-ray diffractometer fitted with an automatic sample changer, a 2 theta-theta goniometer, beam divergence slits, a secondary monochromator and a scintillation counter. The sample was prepared for analysis by packing the powder on to an aluminum sample holder. The specimen was rotated by 60.00 rpm and scanned by 4°/min. Chemical symbols have their usual meanings; b.p. (boiling point), m.p. (melting point), l (liter(s)), ml (milliliter(s)), g (gram(s)), mg (milligram(s)), mol (moles), mmol (millimoles), eq. (equivalent(s)).
Example 1
N-({1-[(4-Hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0299]
Step 1. tert-Butyl ({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)carbamate
[0300] To a stirred solution of tert-butyl (piperidin-4-ylmethyl)carbamate (22.3 g, 104 mmol) in methanol was added 1,6-dioxaspiro[2.5]octane (14.2 g, 124 mmol, Satyamurthy, Nagichettiar et al., Phosphorus Sulfur, 1984, 19, 113) at ambient temperature.
[0301] Then, the mixture was heated at 60° C. for 4 h. The volatile components were removed by evaporation and the resulting viscous oil was precipitated with a mixture of hexane and diethylether. The precipitate was collected by filtration and recrystallized with a mixture of hexane and 2-propanol to give title compound 14.2 g (42%) as a colorless powder.
[0302] MS (ESI) m/z: 329 (M+H + ).
[0303] m.p.: 104° C. 1 H-NMR (CDCl 3 ) δ: 1.23-1.31 (2H, m), 1.44 (9H, s), 1.51-1.69 (8H, m), 2.27-2.38 (4H, m), 2.83-2.88 (2H, m), 3.00 (2H, t, J=6.2 Hz), 3.70-3.85 (4H, m). Anal. Calcd. for C 17 H 32 N 2 O 4 : C, 62.17; H, 9.82; N, 8.53. Found: C, 62.07; H, 9.92; N, 8.58.
Step 2. 4-{[4-(Aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol
[0304] To a solution of tert-butyl ({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)carbamate (50.28 g, 153 mmol) in methanol was added 4N HCl in dioxane (200 mL, 800 mmol) at room temperature. After 4 h, the volatile materials were removed by evaporation. The resulting amorphous was precipitated with diethyl ether/methanol (5:1). The precipitate was collected and added to the ice cooled 6N NaOH aq. (200 mL) gradually. The mixture was extracted with dichloromethane/methanol (10:1) for 4 times. The combined organic phase was washed with brine, dried over MgSO 4 and concentrated to give 24.90 g (99%) of the title compound as pale brown amorphous.
[0305] MS (ESI) m/z: 229 (M+H + ).
[0306] 1 H-NMR (CDCl 3 ) δ: 1.19-1.28 (2H, m), 1.44-1.63 (8H, m), 1.65-1.71 (2H, m), 2.32 (2H, s), 2.35 (2H, t, J=11.0 Hz), 2.57 (2H, d, J=5.7 Hz), 2.85-2.90(2H, m), 3.70-3.81 (4H, m).
Step 3. N-({1-[(4-Hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0307] To a stirred mixture of 1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one ( J. Med. Chem. 1999, 42, 2870-2880) (23.0 g, 130 mmol) and triethylamine (54.6 mL, 392 mmol) in tetrahydrofuran (300 mL) was added triphosgen (38.8 g, 130 mmol) in tetrahydrofuran (200 mL) gradually at room temperature. Then, the mixture was heated at 80° C. for 4 h. After cooling, a solution of 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (step 2 of Example 1) (24.9 g, 109 mmol) and triethylamine (45 mL, 109 mmol) in tetrahydrofuran (500 mL) was added to the mixture. Then, the mixture was heated at 80° C. for 6 h. After cooling, sat. NaHCO 3 aq was added to the mixture. The mixture was extracted with ethyl acetate (500 mL×4). The extracts were washed with brine, dried over MgSO 4 and concentrated. The residue was chromatographed on a column of aminopropyl-silica gel eluting with hexane/ethyl acetate (3:1) to give 31.3 g (67%) of the title compound as a white solid. 1 H NMR (DMSO-d 6 ) δ 8.80 (1H, br t, J=6.0 Hz), 8.06 (1H, m), 7.41(1H, m), 7.19(1H, dt, J=1.5, 7.7 Hz), 7.12(1H, dt, J=1.3, 7.7 Hz), 4.64(1H, septet, J=7.0 Hz), 4.08 (1H, br s), 3.68-3.44 (4H, m), 3.19 (2H, t, J=6.0 Hz), 2.89 (2H, m), 2.20(2H, br s), 2.09(2H, m), 1.68-1.10(9H, m), 1.47(6H, d, J=7.0 Hz).
[0308] MS (ESI) m/z: 431 (M+H + ).
[0309] Anal. Calcd. for C 23 H 34 N 4 O 4 : C, 64.16; H, 7.96; N, 13.01. Found: C, 64.13; H, 7.97; N, 12.99.
[0000] Step 4. N-({1-[(4-Hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide hydrochloride
[0310] To a stirred solution of N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide (27.0 g, 62 mmol) in methanol (150 mL) was added 10% HCl-methanol (100 mL) at ambient temperature. After 30 min, the volatile materials were removed by evaporation. The resulting amorphous was precipitated by ethanol/diethylether. The precipitate was recrystallized from ethanol/diethylether (1:1) to give 26.5 g (90%) of title compound as a colorless powder.
[0311] 1 H-NMR (DMSO-d 6 ) δ: 1.49 (6H, d, J=6.9 Hz), 1.50-1.70 (4H, m), 1.76-1.91 (5H, m), 3.00-3.12 (3H, m), 3.15-3.45 (3H, m), 3.60-3.70 (6H, m), 4.61-4.69 (1H, m), 5.46-5.49 (1H, m), 7.13 (1H, t, J=7.8 Hz) 7.20 (1H, t, J=7.8 Hz), 7.42 (1H, d, J=7.9 Hz), 8.07 (1H, d, J=8.0 Hz), 8.86 (1H, m), 9.61-9.81(1H, m)
[0312] MS (ESI) m/z: 431 (M+H + ).
[0313] Anal. Calcd. for C23H35N4O4Cl: C, 59.15; H, 7.55; N, 2.00. Found: C, 58.81; H, 7.57; N, 11.85.
[0314] Alternative route to synthesize 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol is described below.
Step 1. Benzyl ({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)carbamate
[0315] A mixture of benzyl (piperidin-4-ylmethyl)carbamate (7.77 g, 31.3 mmol, Bose, D. Subhas et al., Tetrahedron Lett., 1990, 31, 6903) and 1,6-dioxaspiro[2.5]octane (4.29 g, 37.6 mmol, Satyamurthy, Nagichettiar et al., Phosphorus Sulfur, 1984, 19, 113) in methanol (93 mL) was stirred at room temperature for 20 h. Then the mixture was refluxed for 8 h. After cooling to room temperature, the solvent was removed in vacuo. The residue was chromatographed on a column of silica gel eluting with methanol/dichloromethane (1:20) to give 5.60 g (49%) of the title compound as a colorless oil.
Step 2. 4-{[4-(Aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol
[0316] A mixture of benzyl ({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)carbamate (5.60 g, 15.5 mmol, step 1) and palladium on activated carbon (10 wt. %, 1.20 g) in methanol (250 mL) was hydrogenated at room temperature for 20 h. Then, the mixture was filtered through a pad of Celite, and the filtrate was concentrated in vacuo to give 3.30 g (94%) of the title compound as slightly yellow oil.
[0317] Following is an another route to synthesize 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol.
[0000] Step 1. 1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidine-4-carboxamide
[0318] The mixture of trimethylsulfoxonium iodide (0.791 g, 3.52 mmol) and 2N—NaOH aq (1.76 mL, 3.52 mmol) in acetonitrile (1.62 mL) was stirred at 50° C. for 30 min. Then to the mixture was added tetrahydro-4H-pyran-4-one (0.324 g, 3.20 mmol) and the resulting mixture was stirred at 50° C. for 3 h. Sat. NaCl aq. (10 mL) was added to the reaction mixture at room temperature and organic layer was extracted with CH 2 Cl 2 (20 mL), dried over Na 2 SO 4 , filtered and concentrated. After removal of the solvent, MeOH (1.62 mL) and isonipecotamide (0.381 g, 2.88 mmol) were added to the residue, the mixture was stirred at 75° C. for 14 h under N 2 . The reaction mixture was concentrated and the residue was recrystallized from MeOH-acetonitrile to give 0.484 g (2.00 mmol) of title compound as a white solid. 1 H-NMR (300 MHz, DMSO-d 6 ) δ 7.19 (br s, 1H), 6.69 (br s, 1H), 4.10 (s, 1H), 3.70-3.50 (m, 4H), 2.95-2.85 (m, 2H), 2.20 (s, 2H), 2.15-1.85 (m, 3H), 1.65-1.50 (m, 6H), 1.40-1.25 (m, 2H).
[0000] Step 2. 4-{[4-(Aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol tosylate
[0319] To a stirred suspension of NaBH 4 (0.505 g, 13.2 g) in triethylene glycol dimethyl ether (12.8 mL) was added the solution 1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidine-4-carboxamide (0.640 g, 2.64 mmol) and AcOH (0.765 mL, 13.2 mmol) in triethylene glycol dimethyl ether (3.2 mL) dropwise at 80° C. under N 2 . The reaction mixture was quenched with 2N—HCl aq until pH value was <3, then the resulting mixture was stirred at room temperature for 1 h. To the mixture CH 2 Cl 2 (30 mL) and 2N—NaOH aq. was added until pH value of aqueous layer was >10. Organic layer was extracted with CH 2 Cl 2 for three times, and the combined organic layer was dried over Na 2 SO 4 , filtered and concentrated.
[0320] To the residual solution (title compound in triethylene glycol dimethyl ether) the solution of p-toluenesulfonic acid monohydrate (0.408 g, 2.11 mmol) in MeOH (1.28 mL) was added at 60° C., then the mixture was cooled to room temperature. Appeared solids were collected by suction and wash with hexane to give title compound (0.340 g, 0.849 mmol) as a white solid.
[0321] 1 H-NMR (300 MHz, DMSO-d 6 ) δ 7.61 (br s, 2H), 7.55-7.40 (m, 2H), 7.15-7.05 (m, 2H), 4.11 (br s, 1H), 3.70-3.45 (m, 4H), 2.95-2.85 (m, 2H), 2.68 (d, J=7.0, 2H), 2.29 (s, 3H), 2.22 (s, 2H), 2.07 (t, J=11.0, 2H), 1.65-1.45 (m, 4H), 1.55-1.35 (m, 1H), 1.40-1.25 (m, 2H), 1.30-1.10 (m, 2H).
Example 2
N-({1-[(4-Hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hemiedisylate
[0322]
[0323] To a stirred solution of N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methy]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide 1.51 g (3.51 mmol) in ethyl acetate (10 mL) and methanol (10 mL) was added a solution of 1,2-ethanedisulfonic acid dihydrate 397 mg (1.75 mmol) in methanol (5.0 mL) and the resulting suspension was stirred for 5 h at room temperatute. The mixture was filtered and the first crop was dried under vacuum for 5 h at 100° C. to give 1.78 g of crude product. 1.61 g of the crude product was dissolved in methanol (20 mL) and ethyl acetate (20 mL) was added to the solution. The resulting suspension was stirred for 2 h at room temperatute. The mixture was filtered and the crop was dried under vacuum for 4 h at 100° C. to give the titled compound 1.13 g (61%) as colorless crystals.
[0324] MS (ESI) m/z: 431 (M+H) + .
[0325] m.p.: 233° C.
[0326] IR (KBr) ν: 2866, 1738, 1683, 1558, 1373, 1217, 1028, 756 cm −1 .
[0327] 1 H NMR (DMSO-d 6 ) δ 8.96 (0.25H, br s), 8.85 (1H, br t, J=6.0 Hz), 8.61 (0.75H, br s), 8.06 (1H, m), 7.43 (1H, m), 7.21 (1H, dt, J=1.3, 7.7 Hz), 7.13 (1H, dt, J=1.2, 7.7 Hz), 5.26 (1H, br s), 4.65 (1H, septet, J=7.0 Hz), 3.74-2.92 (12H, m), 2.64 (2H, s), 2.00-1.35 (9H, m), 1.47 (6H, d, J=7.0 Hz).
[0328] Anal. calcd. for C 23 H 34 N 4 O 4 .0.5 C 2 H 6 O 6 S 2 : C, 54.84; H, 7.09; N, 10.66; S, 6.10.
[0329] Found: C, 54.50; H, 7.24; N, 10.60; S, 6.08.
[0330] PXRD pattern angle (2-Theta°): 10.2, 11.9, 16.3, 17.3, 17.6, 21.8, 24.2.
Example 3
3-Isopropyl-N-{[1-(2-morpholin-4-yl-2-oxoethyl)piperidin-4-yl]methyl}-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Monooxalate
[0331]
[0332] The tilted compound was prepared with the similar method shown in the Step 3 of Preperation 1 by using 4-(chloroacetyl)morpholine (B. G. Hazra; V. S. Pore; S. P. Maybhate, Org. Prep. Proced. Int., 1989, 21, 355-8).
[0333] MS (ESI) m/z: 440 (M+H) + .
[0334] m.p.: 194.2° C.
[0335] IR (KBr) ν: 3443, 2934, 1765, 1728, 1686, 1659, 1612, 1551 cm −1 .
[0336] 1 H-NMR (CDCl 3 ) (free base) δ: 9.00-8.88 (1H, m) 8.30-8.22 (1H, m), 7.23-7.12 (3H, m), 4.78-4.62 (1H, m), 3.66 (4H, s), 3.70-3.58 (4H, m), 3.32 (2H, t, J=6.3 Hz), 3.15 (2H, s), 2.94-2.84 (2H, m), 2.14-2.01 (2H, m), 1.86-1.23 (5H, m), 1.56 (6H, d, J=7.0 Hz).
[0337] 1 H-NMR (DMSO-d 6 ) (salt form) δ: 8.92-8.80 (1H, m) 8.07 (1H, d, J=7.7 Hz), 7.45 (1H, d, J=7.5 Hz), 7.26-7.06 (2H, m), 4.76-4.56 (1H, m), 4.10-2.60 (18H, m), 1.90-1.40 (3H, m), 1.49 (6H, d, J=6.9 Hz).
[0338] Anal. Calcd. for C 25 H 35 N 5 O 8 : C, 56.27; H, 6.61; N, 13.13. Found: C, 56.25; H, 6.82; N, 12.98.
Example 4
3-Isopropyl-N-{[1-(3-morpholin-4-yl-3-oxopropyl)piperidin-4-yl]methyl}-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Monooxalate
[0339]
[0340] A mixture of 3-isopropyl-2-oxo-N-(piperidin-4-ylmethyl)-2,3-dihydro-1H-benzimidazole-1-carboxamide (150 mg, 0.474 mmol) and 4-(3-chloro-propanoyl)-morpholine (G. Mattalia,; C. Serafini; U. Bucciarelli, Fannaco, Ed. Sci., 1976, 31, 457-67) (300 mg, 1.185 mmol) in 4.7 ml N,N-dimethylformamide was added triethylamine (0.23 ml, 1.659 mmol) and sodium iodide (178 ml, 1.185 mmol). The reaction mixture was stirred at 90° C. for 6 days. The reaction mixture was then concentrated by evaporation. The residue was diluted aqueous NaHCO 3 10 ml, extracted with dichloromethane 30 ml for three times. The combined extract was dried over MgSO 4 and concentrated. Preparative TLC (elutent: CH 2 Cl 2 /methanol=10/1) afforded a brown amorphous oil 130 mg (60%). The amorphous (130 mg) was dissolved in 3 ml methanol and acidified with a solution of 24 mg oxalic acid in 2 ml MeOH. The mixture was concentrated. Crystallization of the resulting residue with AcOEt-EtOH afforded a white amorphous 107 mg as the titled compound.
[0341] MS (ESI) m/z: 458 (M+H) + .
[0342] IR (KBr) ν: 3443, 2941, 1732, 1697, 1686, 1647, 1638, 1558 cm −1 .
[0343] 1 H-NMR (CDCl 3 ) (free base) δ: 9.06-8.94 (1H, br) 8.24-8.19 (1H, m), 7.26-7.10 (3H, m), 4.76-4.64 (1H, m), 3.75-2.80 (10H, m), 2.60-1.30 (13H, m), 1.56 (6H, d, J=7.0 Hz).
[0344] 1 H-NMR (CDCl 3 ) (salt form) δ: 9.10-9.00 (1H, m) 8.27-8.17 (1H, m), 7.33-7.12 (3H, m), 4.87-4.62 (1H, m), 3.78-2.65 (16H, m), 2.20-1.60 (7H, m), 1.56 (6H, d, J=6.9 Hz).
[0345] Anal. Calcd. for C 26 H 37 N 5 O 8 .0.9C 2 H 2 O 4 .1.3H 2 O: C, 51.21; H, 6.40; N, 10.74.
[0346] Found: C, 50.90; H, 6.26; N, 11.13.
Example 5
3-Isopropyl-N-{[1-(4-morpholin-4-yl-4-oxobutyl)piperidin-4-yl]methyl}-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide monooxalate
[0347]
[0348] The tilted compound was prepared with the similar method shown in the example 4 by using 4-(4-chloro-butyryl)-morpholine (Schlesinger; Prill; B. G. Hazra; J. Amer. Chem. Soc., 1956, 78, 6123-6124).
[0349] MS (ESI) m/z: 472 (M+H) + .
[0350] IR (KBr) ν: 3443, 1728, 1686, 1647-1616, 1551 cm −1 .
[0351] 1 H-NMR (CDCl 3 ) (free base) δ: 9.02-8.88 (1H, m) 8.31-8.20 (1H, m), 7.22-7.04 (3H, m), 4.80-4.60 (1H, m), 3.66-3.56 (8H, m), 3.40-3.22 (2H, m), 3.00-2.88 (2H, m), 2.50-2.30 (6H, m), 2.00-1.20 (7H, m), 1.57 (6H, d, J=7.1 Hz).
[0352] 1 H-NMR (DMSO-d 6 ) (salt form) δ: 8.93-8.79 (1H, m) 8.07 (1H, d, J=7.5 Hz), 7.44 (1H, d, J=7.5 Hz), 7.27-7.08 (2H, m), 4.75-4.58 (1H, m), 4.47-2.30 (18H, m), 1.90-0.90 (7H, m), 1.49 (6H, d, J=6.9 Hz).
[0353] Anal. Calcd. for C 27 H 39 N 5 O 8 : C, 57.74; H, 7.00; N, 12.47. Found: C, 57.52; H, 7.03; N, 12.32.
Example 6
N-({1-[(trans-1,4-Dihydroxyhexyl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0354]
Step 1. tert-Butyl(1-oxaspiro[2,5]oct-6-yloxy)diphenylsilane
[0355] To a stirred suspension of sodium hydride (60% in mineral oil, 441 mg, 11.0 mmol) in DMSO (7 ml) was added trimethylsulfoxonium iodide (2.53 g, 11.5 mmol) at room temperature, and the mixture was stirred at room temperature for 30 min. To this mixture was added a solution of 4-{[tert-butyl(diphenyl)silyl]oxy}cyclohexanone (Okamura, William H. et al., J. Org. Chem., 1993, 58, 600-610, 3.53 g, 10.0 mmol) in DMSO (35 ml) dropwise at room temperature, the mixture was stirred at room temperature for 2 h. Then the mixture was diluted with water (600 ml), and extracted with diethylether (200 ml×4). The combined organic layer was dried over magnesium sulfate, and concentrated in vacuo. The residue was chromatographed on a column of silica gel eluting with n-hexane/ethyl acetate (1:10), and then purified with PTLC eluting with n-hexane/ethyl acetate (1:15) to give 459 mg (13%, trans) and 390 mg (11%, cis) of the title compound as colorless oil respectively.
[0000] (trans)
[0356] 1 H-NMR (CDCl 3 ) δ: 7.70-7.66 (4H, m), 7.46-7.35 (6H, m), 4.03-3.97 (1H, m), 2.63 (2H, s), 2.07-1.63 (8H, m), 1.08 (9H, s).
[0000] (cis)
[0357] 1 H-NMR (CDCl 3 ) δ: 7.70-7.65 (4H, m), 7.46-7.35 (6H, m), 3.97-3.83 (1H, m), 2.58 (2H, s), 1.83-1.37 (8H, m), 1.07 (9H, s).
Step 2. N-{[1-({trans-4-[tert-Butyl(diphenyl)silyl]oxy-1-hydroxycyclohexyl}methyl)piperidin-4-yl]methyl}-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide.
[0358] A mixture of tert-butyl[(3R,6R)-1-oxaspiro[2.5]oct-6-yloxy]diphenylsilane (Step 1, trans-isomer, 283.0 mg, 0.772 mmol) and 3-isopropyl-2-oxo-N-(piperidin-4-ylmethyl)-2,3-dihydro-1H-benzimidazole-1-carboxamide (Preperation 1, step 2, 2.48 g, 0.0194 mol) in MeOH (4 ml) was heated at 50° C. with stirring for 2 days. After cooling, the reaction mixture was evaporated to remove the solvent, and residue was chromatographed on a column of silica gel eluting with ethyl acetate ln-hexane (1:10) then methanol/dichloromethane (1:20) to give 308.1 mg (58%) of the title compound as a colorless syrup.
[0359] MS (ESI) m/z: 683 (M+H) + .
[0360] 1 H-NMR (CDCl 3 ) δ: 8.93 (1H, m), 8.32-8.23 (1H, m), 7.72-7.60 (4H, m), 7.46-7.32 (6H, m), 7.22-7.10 (3H, m), 4.80-4.62 (1H, m), 3.96 (1H, m), 3.31 (2H, t, J=6.26 Hz), 2.92 (2H, d, J=10.88 Hz), 2.45-2.29 (4H, m), 1.85-1.65 (6H, m), 1.65-1.43 (9H, m, including 6H, d, J=7.09 Hz at 1.56 ppm), 1.43-1.25 (4H, m), 1.06 (9H, s).
Step 3. N-({1-[(trans-1,4-Dihydroxycyclohexyl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide hydrochloride
[0361] A mixture of tert-butyl N-{[1-({trans-4-[tert-butyl(diphenyl)silyl]oxy-1-hydroxycyclohexyl}methyl)piperidin-4-yl]methyl}-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide (234 mg, 0.343 mol) and HCl solution of MeOH (50 ml) was stirred at room temperature for 4 h. Then the solvent was removed in vacuo. The residue was basified with saturated aqueous NaHCO 3 (30 ml), extracted with CH 2 Cl 2 (30 ml×3 times) and the combined organic layer was dried over Na 2 SO 4 . Removal of the solvent gave a residue, which was chromatographed on a column of NH-silica gel eluting with ethyl acetate/n-hexane (1:1-2:1) to give 140.1 mg (92%) of the title compound as a colorless syrup.
[0362] MS (ESI) m/z: 445 (M+H) + .
[0363] 1 H NMR (CDCl 3 ) δ: 8.93 (1H, br t, J=5.87 Hz), 8.32-8.20 (1H, m), 7.25-7.03 (3H, m), 4.80-4.62 (1H, m), 3.94 (1H, m), 3.31 (2H, t, J=6.10 Hz), 2.89 (2H, br d, J=11.53 Hz), 2.36 (2H, s), 2.34 (2H, t, J=11.86 Hz), 2.00-1.85 (2H, m), 1.82-1.25 (18H, m, including 6H, d, J=7.09 Hz at 1.56 ppm).
[0364] 140.1 mg of this syrup was dissolved in HCl solution in MeOH (4 ml), concentrated, and dried in vacuo at 50° C. for 5 h to give 139.2 mg of title compound as a yellow amorphous solid.
[0365] MS (ESI) m/z: 445 (M+H) + .
[0366] 1 H NMR (DMSO-d 6 ) δ: 9.35-8.75 (1H, m), 8.86 (1H, t, J=6.59 Hz), 8.07 (1H, d, J=7.74 Hz), 7.44 (1H, d, J=7.58 Hz), 7.22 (1H, dt, J=1.15 Hz, 7.42 Hz), 7.14 (1H, dt, J=1.32 Hz, 7.74 Hz), 5.04 (1H, br s), 4.75-4.45 (1H, m), 3.70 (1H, br s), 3.59 (2H, d, J=11.70 Hz), 3.50-2.90 (8H, m), 1.90-1.57 (8H, m), 1.57-1.30 (10H, m, including 6H, d, J=6.92 Hz at 1.49 ppm)
[0367] IR(KBr): 3285, 2936, 2677, 1728, 1686, 1611, 1549, 1481, 1375, 1298, 1204, 1157, 1101, 1018, 762 cm −1
[0368] Anal. Calcd for C 24 H 36 N 4 O 4 —HCl-2H 2 O: C, 57.76; H, 7.88; N, 11.23. Found: C, 57.54; H, 7.90; N, 11.21.
[0369] PXRD pattern angle (2-Theta°): 8.3, 14.5, 17.7, 18.3, 19.1, 26.4, 27.5.
Example 7
N-({1-[(cis-1,4-Dihydroxyhexyl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0370]
Step 1. N-{[1-({cis-4-[tert-Butyl(diphenyl)silyl]oxy-1-hydroxycyclohexyl}methyl)piperidin-4-yl]methyl}-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide.
[0371] The title compound was prepared according to the procedure described of Step 2 in the Example 6 using tert-butyl[(3S,6S)-1-oxaspiro[2.5]oct-6-yloxy]diphenylsilane (Example 6, Step 1, cis-isomer, 311.0 mg, 0.848 mmol) instead of tert-butyl[(3R,6R)-1-oxaspiro[2.5]oct-6-yloxy]diphenylsilane.
[0372] MS (ESI) m/z: 683 (M+H) + .
[0373] 1 H-NMR (CDCl 3 ) δ: 8.91 (1H, t, J=5.87 Hz), 8.30-8.22 (1H, m), 7.72-7.63 (4H, m), 7.45-7.30 (6H, m), 7.20-7.10 (3H, m), 4.80-4.63 (1H, m), 3.59 (1H, m), 3.29 (2H, t, J=6.24 Hz), 2.83 (2H, d, J=11.74 Hz), 2.26 (2H, t, J=11.55 Hz), 2.18 (2H, s), 1.85-1.65 (4H, m), 1.65-1.50 (11H, m, including 6H, d, J=7.15 Hz at 1.56 ppm), 1.40-1.30 (2H, m), 1.15-1.00 (11H, m, including 9H, s, 1.05 ppm).
Step 2. N-({1-[(cis-1.4-Dihydroxycyclohexyl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0374] The title compound was prepared according to the procedure described of Step 3 in the Example 6 using N-{[1-({cis-4-[tert-butyl(diphenyl)silyl]oxy-1-hydroxycyclohexyl}methyl)piperidin-4-yl]methyl}-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide (295.0 mg, 0.432 mmol) instead of N-{[1-({trans-4-[diphenyl(trimethylsilyl)methoxy]-1-hydroxycyclohexyl}methyl)piperidin-4-yl]methyl}-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide.
[0375] MS (ESI) m/z: 445 (M+H) + .
[0376] 1 H NMR (CDCl 3 ) δ: 8.93 (1H, br t, J=5.60 Hz), 8.31-8.22 (1H, m), 7.25-7.10 (3H, m), 4.80-4.62 (1H, m), 3.63-3.49 (1H, m), 3.31 (2H, t, J=6.10 Hz), 2.89 (2H, br d, J=11.54 Hz), 2.33 (2H, dt, J=1.81 Hz, 11.70 Hz), 1.85-1.60 (16H, m, including 6H, d, J=7.09 Hz at 1.57 ppm), 1.45-1.18 (4H, m).
[0377] 165.7 mg of this syrup was dissolved in HCl solution in MeOH (4 ml), concentrated, and dried in vacuo at 50° C. for 5 h to give 164.7 mg of title compound as a yellow amorphous solid.
[0378] MS (ESI) m/z: 445 (M+H) + .
[0379] 1 H NMR (DMSO-d 6 ) δ: 9.30-8.90 (1H, m), 8.86 (1H, t, J=5.93 Hz), 8.07 (1H, d, J=7.58 Hz), 7.44 (1H, d, J=7.58 Hz), 7.22 (1H, dt, J=1.48 Hz, 7.75 Hz), 7.15 (1H, dt, J=1.15 Hz, 7.74 Hz), 4.75-4.58 (1H, m), 3.70-2.90 (11H, m), 1.90-1.67 (6H, m), 1.67-1.20 (12H, m, including 6H, d, J=6.92 Hz at 1.49 ppm).
[0380] IR(KBr): 3294, 2936, 2673, 1728, 1686, 1611, 1545, 1479, 1375, 1298, 1203, 1158, 1134, 1101, 1051, 762 cm −1
[0381] Anal. Calcd for C 24 H 36 N 4 O 4 —HCl-5H 2 O: C, 54.79; H, 8.05; N, 10.65. Found: C, 54.75; H, 7.88; N, 10.56.
Example 8
6-Fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0382]
Step 1. 6-Fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0383] The title compound was prepared according to the procedure described in Step 3 of Example 1 from 5-fluoro-1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one (I. Tapia et al., J. Med. Chem., 1999, 42, 2880.) and 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (step 2 of Example 1).
[0384] MS (ESI) m/z: 449 (M+H + ).
[0385] 1 H-NMR (CDCl 3 ) β: 1.12-1.70 (8H, m), 1.55 (6H, d, J=7.0 Hz), 1.74 (2H, brd, 12.8 Hz), 2.31 (2H, s), 2.35 (2H, brt, J=11.9 Hz), 2.88 (2H, brd, J=11.7 Hz), 3.30 (2H, t, J=6.2 Hz), 3.70-3.85 (4H, m), 4.62-4.75 (1H, m), 6.90 (1H, td, J=9.0, 2.4 Hz), 7.02-7.07 (1H, m), 8.05 (1H, dd, J=9.5, 2.6 Hz), 8.85-8.92 (1H, m).
[0000] Step 2. 6-Fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0386] The title compound was prepared according to the procedure described in Step 4 of Example 1 from 6-fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide (step 1 of Example 8).
[0387] MS (ESI) m/z: 449 (M+H + ).
[0388] 1 H-NMR (DMSO-d 6 ) δ: 1.46 (6H, d, J=6.9 Hz), 1.55-1.65 (4H, m), 1.70-1.91 (4H, m), 2.90-3.28 (8H, m), 3.50-3.67 (6H, m), 4.56-4.69 (1H, m), 5.30-5.37 (1H, m), 5.76 (1H, s), 7.08 (1H, td, J=9.0, 2.4 Hz), 7.44-7.49 (1H, m), 7.85 (1H, dd, J=9.5, 2.5 Hz), 8.81-8.85 (1H, m).
[0389] Anal. Calcd. for C 23 H 34 FN 4 O 4 Cl: C, 56.96; H, 7.07; N, 11.55. Found: C, 57.00; H, 7.20; N, 11.43.
[0390] PXRD pattern angle (2-Theta°): 10.0, 14.6, 16.2, 18.5, 23.2, 25.3, 27.3.
Example 9
5-fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0391]
Step 1. (5-fluoro-2-nitrophenyl)isopropylamine
[0392] To a stirred mixture of 2,4-difluoro-1-nitrobenzene (4.77 g, 30 mmol) and K2CO3 (4.14 g, 30 mmol) in THF (30 mL) was added isopropyl amine (1.77 g, 30 mmol) in THF (10 mL) at 0° C. After being stirred for 13 h, the insoluble materials were removed by pad of Celite and the filtrate was consentrated under reduced pressure to give title compound (5.25 g, 88%) as a pale yellow oil.
[0393] MS (ESI) m/z: 405 (M+H + ).
[0394] 1 H NMR (CDCl 3 ): δ 8.21 (1H, dd, J=9.3, 6.0 Hz), 6.48 (1H, dd, J=11.7, 2.6 Hz), 6.39-6.29 (1H, m), 3.81-3.66 (1H, m), 1.33 (6H, d, J=6.4 Hz)
[0000] Step 2. 6-fluoro-1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one
[0395] A mixture of (5-fluoro-2-nitrophenyl)isopropylamine (Step 1 of Example 9, 5.85 g, 30 mmol) and 10% Pd—C (600 mg) in MeOH was stirred under atmosphere of hydrogen gas at at room temperature for 12 h. The catalyst was filtered off on a pad of Celite, and the filtrate was evaporated under reduced pressure. To the residue was added 1,1′-carbonyldiimidazole (4.5 g, 28 mmol) and THF (100 μL) and then stirred at 100° C. for 10 h. After cooling, the volatile materials were removed under reduced pressure and the residue was partitioned between ethylacetate and H 2 O. After extraction with ethylacetate (3 times), the combined organic phase was washed with brine, dried over MgSO 4 and concentrated. The residue was chromatographed on a column of silica gel eluting with hexane/ethyl acetate (2:1) to give 3.47 g (60%) of the title compound as a white solid.
[0396] MS (ESI) m/z: 195 (M+H + ), 193 (M−H + ).
[0397] 1 H NMR (CDCl 3 ): δ 7.06-6.99 (1H, m), 6.90 (1H, dd, J=9.2, 2.4 Hz), 6.82-6.72 (1H, m), 4.83-4.62 (1H, m), 1.54 (6H, d, J=7.1 Hz)
[0000] Step 3. 5-fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0398] To a stirred mixture of 6-fluoro-1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one (Step 2 of Example 9, 0.58 g, 3 mmol) and p-nitrophenylchloroformate (0.66 g, 3.3 mmol) in dichloromethane (15 mL) was added triethylamine (1.25 mL, 9.0 mmol) at room temperature. After being stirred for 2 h, a solution of 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (Step 2 of Example 1, 0.75 g, 3.3 mmol) in dichloromethane (15 mL) was added to the mixture. After being stirred for 4 h, the mixture was diluted with ethyl acetate (100 mL). Then, the organic layer was washed with 0.5 N NaOH aq. (10 mL) for 5 times and brine, dried over MgSO 4 and concentrated. The residue was chromatographed on a column of aminopropyl-silica gel eluting with hexane/ethyl acetate (3:1) to give 0.97 g (79%) of the title compound as a white solid.
[0399] MS (ESI) m/z: 449 (M+H + ).
[0400] 1 H NMR (CDCl 3 ): δ 8.84-8.74 (1H, m), 8.21-8.11 (2H, m), 7.02-6.91 (2H, m), 4.68-4.56 (1H, m), 3.87-3.72 (4H, m), 3.34-3.25 (2H, m), 2.93-2.82 (2H, m), 2.42-2.25 (4H, m), 1.79-1.68 (2H, m), 1.67-1.29 (13H, m).
[0401] Anal. calcd. for C 23 H 33 N 4 O 4 F: C, 61.59; H, 7.42; N, 12.49. Found: C, 61.45; H, 7.33; N, 12.40.
Example 10
5,6-difluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0402]
Step 1. 4,5-difluoro-N-isopropyl-2-nitroaniline
[0403] 4,5-difluoro-2-nitroaniline (3.48 g, 20 mmol), 2,2-dimethoxypropane (11.9 mL, 100 mmol), and trifluoroacetic acid (1.6 mL, 21 mmol) were dissolved in toluene (40 mL) and stirred at room temperature for 1 h. A boron-pyridine complex (2.12 mL, 21 mmol) was slowly added. The reaction mixture was stirred for 20 h. The solvent was evaporated in vacuo, and the residue was taken up into water and extracted with dichloromethane. The organic extract was dried (Na 2 SO 4 ) and concentrated in vacuo. The residue was chromatographed on a column of aminopropyl-silica gel eluting with hexane/ethyl acetate (30:1) to give 2.42 g (56%) of the title compound as a bright orange solid.
[0404] 1 H NMR (CDCl 3 ): δ 8.05 (1H, dd, J=10.8, 8.6 Hz), 6.61 (1H, dd, J=12.6, 6.8 Hz), 3.77-3.62 (1H, m), 1.33 (6H, d, J=6.2 Hz).
[0000] Step 2. 5,6-difluoro-1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one
[0405] The title compound was prepared according to the procedure described in Step 2 of Example 9 from 4,5-difluoro-N-isopropyl-2-nitroaniline (Step 1 of Example 10).
[0406] MS (ESI) m/z: 213 (M+H + ), 211 (M+H + ).
[0407] 1 H NMR (CDCl 3 ): δ 7.00-6.89 (2H, m), 4.76-4.57 (1H, m), 3.86-3.69 (4H, m), 3.31 (2H, t, J=7.0 Hz), 2.95-2.82 (2H, m), 2.35 (2H, t, J=, 13.7 Hz), 2.31(2H, s), 1.67-1.25 (10H, m), 1.55 (6H, d, J=7.7 Hz).
[0000] Step 3. 5,6-difluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2.3-dihydro-1H-benzimidazole-1-carboxamide
[0408] The title compound was prepared according to the procedure described in Step 3 of Example 9 from 5,6-difluoro-1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one (Step 2 of Example 10) and 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (Step 2 of Example 1).
[0409] MS (ESI) m/z: 467 (M+H + ).
[0410] 1 H NMR (CDCl 3 ): δ 8.88-8.78 (1H, m), 8.25-8.15 (1H, m), 6.94-6.79 (2H, m), 4.73-4.57 (1H, m), 3.86-3.69 (4H, m), 3.31 (2H, t, J=7.0 Hz), 2.95-2.82 (2H, m), 2.35 (2H, t, J=, 13.7 Hz), 2.31 (2H, s), 1.67-1.25 (10H, m), 1.55 (6H, d, J=7.7 Hz).
[0000] Step 4. 5,6-difluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0411] A mixture of 5,6-difluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide (Step 3 of Example 10, 113 mg, 0.242 mmol) and 10% HCl-methanol (5 mL) was stirred for 1 h. Then, the volatile components were removed under reduced pressure and the residue was recrystallized from ethanol-diethyl ether to give 88 mg (72%) of the title compound as a colorless powder.
[0412] MS (ESI) m/z: 467 (M+H + ).
[0413] 1 H NMR (DMSO-d 6 ): δ 8.82-8.71 (1H, m), 8.08-7.93 (1H, m), 7.78-7.67 (1H, m), 5.35-5.26 (1H, m), 4.69-4.52 (1H, m), 3.70-3.51 (6H, m), 3.41-2.91 (7H, m), 1.94-1.53 (8H, m), 1.45 (6H, d, J=7.0 Hz).
[0414] Anal. calcd. for C 23 H 33 N 4 O 4 F 2 Cl.1H 2 O: C, 53.96; H, 6.69; N, 10.94. Found: C, 53.67; H, 6.64; N, 10.89.
Example 11
6-chloro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0415]
Step 1. 6-chloro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0416] The title compound was prepared according to the procedure described in Step 3 of Example 9 from 5-chloro-1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one (I. Tapia et al., J. Med. Chem., 42, 2880 (1999)) and 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (Step 2 of Example 1).
[0417] MS (ESI) m/z: 465 (M+H + ).
[0418] 1 H NMR (CDCl 3 ): δ 8.33-8.30 (1H, m), 7.19-7.14 (1H, m), 7.04-7.03 (1H, m), 4.73-4.57 (1H, m), 3.82-3.71 (4H, m), 3.31 (2H, t, J=6.4 Hz), 2.95-2.83 (2H, m), 2.41-2.29 (4H, m), 1.79-1.68 (2H, m), 1.67-1.25 (8H, m), 1.54 (6H, d, J=7.0 Hz).
[0000] Step 2. 6-chloro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide hydrochloride
[0419] The title compound was prepared according to the procedure described in Step 4 of Example 10 from 6-chloro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide (Step 1 of Example 11).
[0420] MS (ESI) m/z: 465 (M+H + ).
[0421] 1 H NMR (DMSO-d 6 ): δ 8.84-8.76 (1H, m), 8.10-8.07 (1H, m), 7.51-7.45 (1H, m), 7.32-7.25 (1H, m), 5.38-5.32 (1H, m), 4.73-4.56 (1H, m), 3.70-3.55 (6H, m), 3.41-2.91 (7H, m), 1.95-1.58 (8H, m), 1.48 (6H, d, J=7.7 Hz).
[0422] Anal. calcd. for C 23 H 34 N 4 O 4 Cl 2 ˜0.5H 2 O: C, 54.12; H, 6.91; N, 10.98. Found: C, 53.85; H, 6.90; N, 10.78.
Example 12
5-chloro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0423]
Step 1. 5-chloro-N-isopropyl-2-nitroaniline
[0424] The title compound was prepared according to the procedure described in Step 1 of Example 10 from 5-chloro-2-nitroaniline.
[0425] 1 H NMR (CDCl 3 ): δ 8.12 (1H, d, J=9.2 Hz), 6.84 (1H, d, J=2.0 Hz), 6.57 (1H, dd, J=9.2, 2.0 Hz), 3.81-3.71 (1H, m), 1.33 (6H, d, J=6.2 Hz)
[0000] Step 2. 6-chloro-1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one
[0426] A mixture of 5-chloro-N-isopropyl-2-nitroaniline (Step 1 of Example 12, 0.76 g, 3.54 mmol), iron (0.99 g, 17.7 mmol) and ammonium chloride (0.38 g, 7.08 mmol) was suspended in ethanol (27 mL) and H 2 O (9 mL). Then, the mixture was heated at 80° C. for 3 h. After cooling, the insoluble materials was filtered off on a pad of Celite, and the filtrate was evaporated under reduced pressure. To the residue was added N,N′-carbonyldiimidazole (CDI, 0.57 g, 3.50 mmol) and THF (10 mL) and then stirred at 100° C. for 10 h. After cooling, the volatile materials were removed under reduced pressure and the residue was partitioned between ethylacetate and H 2 O. After extraction with ethylacetate (3 times), the combined organic phase was washed with brine, dried over MgSO 4 and concentrated. The residue was chromatographed on a column of silica gel eluting with hexane/ethyl acetate (2:1) to give 0.30 g (40%) of the title compound as a white solid.
[0427] 1 H NMR (CDCl 3 ): δ 6.99-6.90 (2H, m), 6.84-6.74 (1H, m), 4.94-4.77 (1H, m), 1.64 (6H, d, J=7.0 Hz)
[0000] Step 3. 5-chloro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0428] The title compound was prepared according to the procedure described in Step 3 of Example 9 from 6-chloro-1-isopropyl-1,3-dihydro-2H-benzimidazol-2-one (Step 2 of Example 12) and 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (Step 2 of Example 1).
[0429] MS (ESI) m/z: 465 (M+H + ).
[0430] 1 H NMR (CDCl 3 ): δ 8.88-8.78 (1H, m), 8.21-8.14 (1H, m), 7.19-7.10 (2H, m), 4.73-4.56 (1H, m), 3.87-3.69 (4H, m), 3.30 (2H, t, J=6.2 Hz), 2.94-2.84 (2H, m), 2.41-2.27 (4H, m), 1.79-1.68 (2H, m), 1.67-1.25 (11H, m).
[0431] Anal. calcd. for C 23 H 33 N 4 O 4 Cl: C, 59.41; H, 7.15; N, 12.05. Found: C, 59.27; H, 7.10; N, 11.72.
Example 13
N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-5-methyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0432]
Step 1. N-isopropyl-5-methyl-2-nitroaniline
[0433] The title compound was prepared according to the procedure described in Step 1 of Example 9 from 2-fluoro-4-methyl-1-nitrobenzene.
[0434] 1 H NMR (CDCl 3 ): δ 8.12-8.01 (2H, m), 6.63 (1H, brs), 6.42 (1H, d, J=10.3 Hz), 3.94-3.72 (1H, m), 2.33 (3H, s), 1.32 (6H, d, J=6.4 Hz)
[0000] Step 2. 1-isopropyl-6-methyl-1,3-dihydro-2H-benzimidazol-2-one
[0435] The title compound was prepared according to the procedure described in Step 2 of Example 9 from N-isopropyl-5-methyl-2-nitroaniline (Step 1 of Example 13).
[0436] MS (ESI) m/z: 191 (M+H + ).
[0437] 1 H NMR (CDCl 3 ): δ 7.04-6.93 (2H, m), 6.90-6.80 (1H, m), 4.82-4.63 (1H, m), 2.40 (3H, s), 1.55 (6H, d, J=7.0 Hz).
[0000] Step 3. N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-5-methyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0438] The title compound was prepared according to the procedure described in Step 3 of Example 9 from 1-isopropyl-6-methyl-1,3-dihydro-2H-benzimidazol-2-one (Step 2 of Example 13) and 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (Step 2 of Example 1).
[0439] MS (ESI) m/z: 445 (M+H + ).
[0440] 1 H NMR (CDCl 3 ): δ 8.97-8.84 (1H, m), 8.10 (1H, d, J=8.8 Hz), 7.01-6.93 (2H, m), 4.76-4.58 (1H, m), 3.85-3.69 (4H, m), 3.30 (2H, t, J=6.4 Hz), 2.94-2.82 (2H, m), 2.41 (3H, s), 2.43-2.27 (4H, m), 1.80-1.68 (2H, m), 1.67-1.25 (11H, m).
[0441] Anal. calcd. for C 24 H 36 N 4 O 4 : C, 64.84; H, 8.16; N, 12.60. Found: C, 64.78; H, 8.29; N, 12.58.
Example 14
N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-4-methyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0442]
Step 1. N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-4-methyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0443] The title compound was prepared according to the procedure described in Step 3 of Example 9 from 1-isopropyl-7-methyl-1,3-dihydro-2H-benzimidazol-2-one (I. Tapia et al., J. Med. Chem., 42, 2880 (1999)) and 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (Step 2 of Example 1).
[0444] MS (ESI) m/z: 445 (M+H + ).
[0445] 1 H NMR (CDCl 3 ): δ9.11-8.97 (1H, m), 8.17 (1H, d, J=7.7 Hz), 7.10-6.88 (2H, m), 4.99-4.82 (1H, m), 3.91-3.69 (4H, m), 3.29 (2H, t, J=6.2 Hz), 2.94-2.82 (2H, m), 2.59 (3H, s), 2.43-2.27 (4H, m), 1.84-1.19 (7H, m), 1.62 (6H, d, J=6.8 Hz).
[0446] Anal. calcd. for C 24 H 36 N 4 O 4 : C, 64.84; H, 8.16; N, 12.60. Found: C, 64.73; H, 8.35; N, 12.56.
Example 15
N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-4,5-dimethyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0447]
Step 1. N-isopropyl-2,3-dimethyl-6-nitroaniline
[0448] The title compound was prepared according to the procedure described in Step 1 of Example 10 from 2,3-dimethyl-6-nitroaniline.
[0449] 1 H NMR (CDCl 3 ): δ 7.82 (1H, d, J=8.6 Hz), 6.79 (1H, d, J=8.4 Hz), 3.52-3.34 (1H, m), 2.30 (3H, s), 2.24 (3H, s), 1.11 (6H, d, J=6.2 Hz)
[0000] Step 2. 1-isopropyl-6,7-dimethyl-1,3-dihydro-2H-benzimidazol-2-one
[0450] The title compound was prepared according to the procedure described in Step 2 of Example 9 from N-isopropyl-2,3-dimethyl-6-nitroaniline (Step 1 of Example 15).
[0451] 1 H NMR (CDCl 3 ): δ 7.11 (1H, brs), 6.92-6.70 (1H, m), 5.00-4.82 (1H, m), 2.45 (3H, s), 2.32 (3H, s), 1.63 (6H, d, J=7.0 Hz).
[0000] Step 3. N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-4,5-dimethyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0452] To a stirred mixture of 1-isopropyl-6,7-dimethyl-1,3-dihydro-2H-benzimidazol-2-one (Step 2 of Example 15, 204 mg, 1 mmol) and p-nitrophenylchloroformate (220 mg, 1.1 mmol) in dichloromethane (7 mL) was added triethylamine (0.42 mL, 3.0 mmol) at room temperature. After being stirred for 2 h, a solution of 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (Step 2 of Example 1, 230 mg, 1.0 mmol) in dichloromethane (3 mL) was added to the mixture. After being stirred for 4 h, the mixture was diluted with ethyl acetate (50 mL). Then, the organic layer was washed with 0.5 N NaOH aq. (5 mL) for 5 times and brine, dried over MgSO 4 and concentrated. The residue was filtered through pad of aminopropyl-silica gel eluting with hexane/ethyl acetate (3:1) and the filtrate was concentrated. To the mixture was added 10% HCl-methanol (5 mL) was stirred for 1 h. Then, the volatile components were removed under reduced pressure and the residue was recrystallized from ethanol-diethyl ether to give 100 mg (20%) of the title compound as a colorless powder.
[0453] MS (ESI) m/z: 459 (M+H + ).
[0454] 1 H NMR (DMSO-d 6 ): δ 8.96-8.87 (1H, m), 7.84 (1H, d, J=8.3 Hz), 6.95 (1H, d, J=8.3 Hz), 5.34-5.21 (1H, m), 5.01-4.86 (1H, m), 3.69-3.53 (6H, m), 3.41-2.91 (7H, m), 2.45 (3H, s), 2.28 (3H, s), 1.87-1.70 (3H, m), 1.67-1.48 (5H, m), 1.52 (6H, d, J=6.6 Hz).
[0455] Anal. calcd. for C 25 H 39 N 4 O 4 Cl.0.5H 2 O: C, 59.57; H, 8.00; N, 11.12. Found: C, 59.53; H, 7.98; N, 11.10.
Example 16
6-fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-5-methyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide Hydrochloride
[0456]
Step 1. 4-fluoro-N-isopropyl-5-methyl-2-nitroaniline
[0457] The title compound was prepared according to the procedure described in Step 1 of Example 9 from 1,4-difluoro-2-methyl-5-nitrobenzene (T. Timothy et al., J. Med. Chem., 35, 2321 (1992)).
[0458] MS (ESI) m/z: 213 (M+H + ).
[0459] 1 H NMR (CDCl 3 ): δ 7.82 (1H, d, J=10.3 Hz), 6.64 (1H, d, J=6.4 Hz), 3.88-3.67 (1H, m), 2.30 (3H, s), 1.31 (6H, d, J=6.4 Hz)
[0000] Step 2. 5-fluoro-1-isopropyl-6-methyl-1,3-dihydro-2H-benzimidazol-2-one
[0460] The title compound was prepared according to the procedure described in Step 2 of Example 9 from 4-fluoro-N-isopropyl-5-methyl-2-nitroaniline (Step 1 of Example 16).
[0461] MS (ESI) m/z: 209 (M+H + ).
[0462] 1 H NMR (CDCl 3 ): δ 7.00-6.96 (1H, m), 6.92-6.90 (1H, m), 4.75-4.56 (1H, m), 2.31 (3H, s), 1.55 (6H, d, J=7.0 Hz).
[0000] Step 3. 6-fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-5-methyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0463] The title compound was prepared according to the procedure described in Step 3 of Example 9 from 5-fluoro-1-isopropyl-6-methyl-1,3-dihydro-2H-benzimidazol-2-one (Step 2 of Example 16) and 4-{[4-(aminomethyl)piperidin-1-yl]methyl}tetrahydro-2H-pyran-4-ol (Step 2 of Example 1).
[0464] MS (ESI) m/z: 463 (M+H + ).
[0465] 1 H NMR (CDCl 3 ): δ 8.92-8.83 (1H, m), 7.96 (1H, d, J=10.1 Hz), 6.91 (1H, d, J=6.2 Hz), 4.75-4.56 (1H, m), 3.85-3.70 (4H, m), 3.30 (2H, t, J=6.4 Hz), 2.94-2.82 (2H, m), 2.42-2.29 (7H, m), 1.84-1.19 (7H, m), 1.55 (6H, d, J=7.0 Hz).
[0000] Step 4. 6-fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-5-methyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide hydrochloride
[0466] The title compound was prepared according to the procedure described in Step 4 of Example 10 from 6-fluoro-N-({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)-3-isopropyl-5-methyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide (Step 3 of Example 16).
[0467] MS (ESI) m/z: 463 (M+H + ).
[0468] 1 H NMR (DMSO-d 6 ): 89.55-9.11 (1H, m), 8.89-8.74 (1H, m), 7.77 (1H, d, J=10.4 Hz), 7.40 (1H, d, J=6.6 Hz), 5.42-5.34 (1H, m), 4.70-4.56 (1H, m), 3.69-3.53 (6H, m), 3.52-2.91 (7H, m), 2.29 (3H, s), 1.87-1.70 (3H, m), 1.95-1.55 (8H, m), 1.48 (6H, d, J=6.8 Hz).
[0469] Anal. calcd. for C 24 H 36 N 4 O 4 FCl: C, 57.76; H, 7.27; N, 11.23. Found: C, 57.47; H, 7.40; N, 11.05.
[0000] Preparation 1.
[0470] Step 1. tert-Butyl 4-({[(3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)carbonyl]amino}methyl)piperidine-1-carboxylate
[0471] To a stirred solution of 1-isopropyl-1,3-dihydro-2H-benzimidazol-2one ( J. Med. Chem. 1999, 42, 2870-2880) (3.00 g, 17.02 mmol) and triethylamine (7.12 ml, 51.06 mmol) in 70 ml tetrahydrofuran was added triphosgen (5.15 g, 17.02 mmol) in 14 ml tetrahydrofuran at room temperature. The reaction mixture was refluxed for 19 hours. The mixture was then cooled to room temperature, tert-butyl 4-(aminomethyl)piperidine-1-carboxylate (J. Prugh, L. A. Birchenough and M. S. Egbertson, Synth. Commun., 1992, 22, 2357-60) (3.28 g, 15.32 mmol) in 10 ml tetrahydrofuran was added. The reaction mixture was refluxed for another 24 hours. Then cooled and basified with aqueous saturated NaHCO 3 50 ml, and extracted with ethyl acetate 100 ml for three times. The combined extract was washed with brine, dried over MgSO 4 and concentrated. Flash chromatography of the residue (elutent: hexane/ethyl acetate=5/1 to 1/2) afforded a colorless oil 3.99 g (62%) as the titled compound.
[0472] 1 H-NMR (CDCl 3 ) δ: 9.04-8.88 (1H, m), 8.83-8.20 (1H, m), 7.26-7.10 (3H, m), 4.80-4.60 (1H, m), 4.28-4.02 (2H, m), 3.32 (2H, t, J=6.1 Hz), 2.82-2.60 (2H, m), 1.94-1.10 (5H, m), 1.57 (6H, d, J=7.1 Hz), 1.45 (9H, s).
Step 2. 3-Isopropyl-2-oxo-N-(piperidin-4-ylmethyl)-2,3-dihydro-1H-benzimidazole-1-carboxamide
[0473] A solution of tert-butyl 4-({[(3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)carbonyl]amino}methyl)piperidine-1-carboxylate (3.992 g, 9.58 mmol) in 50 ml 10% hydrochloric acid in methanol and 10 ml concentrated hydrochloric acid was stirred at room temperature for 18 hours. The mixture was then concentrated and basified with aqueous Na 2 CO 3 , extracted with CHCl 3 100 ml for 3 times. The combined extract was dried and concentrated. Flash chromatography of the residue (NH-silica gel, elutent: CH 2 Cl 2 /methanol=100/1) afforded a colorless oil 2.272 g (75%) as the titled compound.
[0474] MS (ESI) m/z: 317 (M+H) + .
[0475] 1 H-NMR (CDCl 3 ) δ: 8.93 (1H, br), 8.32-8.22 (1H, m), 7.24-7.02 (3H, m), 4.80-4.61 (1H, m), 3.31 (2H, t, J=6.0 Hz), 3.20-3.05 (2H, m), 2.79-2.54 (2H, m), 1.84-1.52 (3H, m), 1.57 (6H, d, J=6.9 Hz), 1.36-1.13 (2H, m).
Step 3. N-{[1-(3-Hydroxy-3-methyl-2-oxobutyl)piperidin-4-yl]methyl}-3-isopropyl-2-oxo-2,3-dihydro-1H-benzimidazole-1-carboxamide, Monooxalate Salt
[0476] A mixture of 3-isopropyl-2-oxo-N-(piperidin-4-ylmethyl)-2,3-dihydro-1H-benzimidazole-1-carboxamide (250 mg, 0.790 mmol), 1-bromo-3-hydroxy-3-methylbutan-2-one (G. Bertram; A. Scherer; W. Steglich; W. Weber, Tetrahedron Lett., 1996, 37, 7955-7958) (181 mg, 1.343 mmol) and triethylamine (0.28 ml, 1.975 mmol) in 8 ml tetrahydrofuran was refluxed for 15 hours. Then cooled and diluted with 100 ml ethyl acetate and was washed with aqueous NaHCO 3 20 ml, brine, dried over MgSO 4 and concentrated. Flash chromatography of the residue (elutent: CH 2 Cl 2 /methanol=100/1 to 30/1) afforded a colorless oil 202 mg (61%). The oil (202 mg) was dissolved in 3 ml methanol and acidified with a solution of 44 mg oxalic acid in 1 ml MeOH. The mixture was concentrated. Recrystallization of the resulting solid with EtOH—AcOEt afforded a white solid 246 mg as the titled compound.
[0477] MS (ESI) m/z: 417 (M+H) + .
[0478] m.p.: 140.5° C.
[0479] IR (KBr) ν: 3404, 3306, 2980, 2941, 1728, 1690, 1612, 1541 cm −1 .
[0480] 1 H-NMR (CDCl 3 ) (free base) δ: 8.90 (1H, br) 8.30-8.20 (1H, m), 7.24-7.10 (3H, m), 4.78-4.61 (1H, m), 3.37 (2H, s), 3.33 (2H, t, J=6.3 Hz), 3.00-2.86 (2H, m), 2.22-2.06 (2H, m), 1.90-1.22 (5H, m), 1.57 (6H, d, J=7.0 Hz), 1.35 (6H, s).
[0481] 1 H-NMR (DMSO-d 6 ) (salt form) δ: 8.92-8.81 (1H, m) 8.07 (1H, dd, J=7.7, 6.8 Hz), 7.44 (1H, d, J=7.7 Hz), 7.28-7.10 (2H, m), 4.74-4.60 (1H, m), 4.36 (2H, by), 4.00-2.70 (6H, m), 1.90-1.44 (5H, m), 1.49 (6H, d, J=6.4 Hz), 1.24 (6H, s).
[0482] Anal. Calcd. for C 24 H 34 N 4 O 8 .0.3C 2 H 6 O.1H 2 O: C, 54.88; H, 7.08; N, 10.41. Found: C, 55.26; H, 7.18; N, 10.07.
[0483] All publications, including but not limited to, issued patents, patent applications, and journal articles, cited in this application are each herein incorporated by reference in their entirety.
[0484] Although the invention has been described above with reference to the disclosed embodiments, those skilled in the art will readily appreciate that the specific experiments detailed are only illustrative of the invention. It should be understood that various modifications can be made without departing from the spirit of the invention. Accordingly, the invention is limited only by the following claims. | This invention provides a compound of the formula (I):
or a pharmaceutically acceptable salt thereof, and compositions containing such compounds and the use of such compounds for the manufacture of medicament for gastroesophageal reflux disease, gastrointestinal disease, gastric motility disorder, non-ulcer dyspepsia, functional dyspepsia, irritable bowel syndrome (IBS), constipation, dyspepsia, esophagitis, gastroesophageral disease, nausea, central nervous system disease, Alzheimer's disease, cognitive disorder, emesis, migraine, neurological disease, pain, cardiovascular disorders, cardiac failure, heart arrhythmia, diabetes and apnea syndrome.
These compounds have 5-HT 4 receptor agonistic activity, and thus are useful for the treatment of gastroesophageal reflux disease, non-ulcer dyspepsia, functional dyspepsia, irritable bowel syndrome or the like in mammalian, especially humans. | 2 |
BACKGROUND
[0001] The invention relates generally to the field of tumor visualization. More particularly, the invention relates to the evaluation and selection of dyes for tumor visualization.
[0002] In operative procedures to remove tumors, the surgeon's ultimate goal consists of removing all of the cancerous tissue while sparing as much of the normal tissue as possible. A surgeon must make a visual assessment of the outer boundary of the tumor and then try to completely resect the tumor. A successful resection of the whole tumor generally results in a greater 5-year survival rate for patients than a partial resection. Various imaging techniques may be used preoperatively or intraoperatively in order to determine the extent of the tumor. However, these images may fail to identify the outer layer of the tumor. Thus, after resection of the tumor some tumor cells may remain. The continued presence of such tumor cells may be problematic to the extent that residual tumor cells can lead to a local recurrence and, thus, properly identifying and removing the tumor boundary is a key focus in surgery to remove a tumor.
[0003] As one might expect, factors that impact the likelihood of local recurrence include the skill of the surgeon performing the tumor resection and the information available to the surgeon. In particular, as suggested above, one reason why surgical treatment may fail in the early stages of cancer is because the entire tumor may not be removed (i.e., lack of clear margins). At present, the surgeon typically relies on visual inspection and palpitation during tumor resection. However it is often difficult to distinguish cancer tissue from normal tissue by sight and/or by touch.
[0004] Therefore, information that may be used to delineate the tumor boundary intra-operatively may improve the effectiveness of resection procedures and thereby diminish the probability of local tumor recurrence. Given the importance of correctly identifying the boundaries of tumors, there is a need to develop tools to help recognize and highlight the tumor boundary in a variety of clinical contexts.
BRIEF DESCRIPTION
[0005] The present disclosure relates to the automatic identification of tumor boundaries with in image or images and the quantification of characteristics of these boundaries. In one embodiment, user input is provided to locate a dye-stained tumor in an image and, based upon this input, automated routines are employed to identify the boundary of the tumor. Characteristics of the boundary (such as measures related to average intensity, variance, contrast, or breaks in the boundary) may then be automatically measured and quantified and used as a basis for comparing the performance of the dye to other dyes or for comparing the performance of the same dye in different clinical contexts. In some embodiments, an intensity level standardization may be performed to standardize the intensity levels in each image so that the comparison of boundary characteristics between images is more meaningful.
[0006] In one embodiment, a method is provided that includes the act of accessing an image of a subject. The subject is administered an agent labeled with a dye prior to generation of the image. A tumor labeled with the dye is selected from the image. A first routine is employed to detect some or all of the boundary of the tumor. A second routine is employed to measure one or more characteristics of the boundary.
[0007] In another embodiment, a method for selecting dyes is provided that includes the act of accessing a plurality of images of tumors. The tumors are each stained with a respective image-enhancing dye of a plurality of dyes prior to imaging. The plurality of images are processed to identify the respective tumor boundaries within each image. One or more routines are employed to calculate one or more quantitative characteristics of each tumor boundary. One or more of the plurality of dyes are selected based on the one or more quantitative characteristics.
[0008] In another embodiment, a method for processing infrared image data to identify a tumor's boundary is provided. The method includes the act of administering an agent labeled with a fluorescent dye to a subject. An infrared image of the subject is generated and a tumor is selected from the image. A first computer-implemented algorithm is executed to identify the tumor's boundary. A second computer-implemented algorithm is executed to generate one or more quantitative characteristics of the tumor boundary. The one or more quantitative characteristics are reviewed to assess the performance of the fluorescent dye.
[0009] In another embodiment, a method is provided that includes the act of receiving an input indicative of the location of a dye-enhanced tumor in an image. A first routine configured to determine the boundary of the tumor in the image is executed. A second routine configured to calculate one or more quantitative characteristics of the boundary of the tumor is executed. The one or more quantitative characteristics are stored or displayed.
[0010] In yet another embodiment, a system is provided. The system includes a display capable of displaying an image of a dye-enhanced tumor and an input device configured to receive an operator input indicative of the location of the dye-enhanced tumor in the image. the system also includes a storage or memory device storing routines for determine the boundary of the dye-enhanced tumor and for calculating one or more quantitative characteristics of the boundary. In addition, the system includes a processor configured to receiving the operator input, to execute the routines stored in the storage or memory device in view of the operator input, and to display the one or more quantitative characteristics on the display.
DRAWINGS
[0011] These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
[0012] FIG. 1 is a flow chart depicting acts for characterizing tumor boundaries according to one aspect of the present disclosure;
[0013] FIG. 2 is a screenshot illustrating the selection of a tumor and identification of the tumor's boundary according to one aspect of the present disclosure
[0014] FIG. 3 is a screenshot illustrating the identification of a tumor's boundary and display of quantitative characteristics associated with the boundary according to one aspect of the present disclosure;
[0015] FIG. 4 is a flow chart acts for selecting dyes according to one aspect of the present disclosure; and
[0016] FIG. 5 is a schematic representation of a processor-based system for executing routines used in implementing aspects of the present disclosure.
DETAILED DESCRIPTION
[0017] As used herein, the term dye or dyes includes (but is not limited to) organic or inorganic fluorophores, fluorescent nanoparticles, fluorescent beads as well as their derivatives and conjugates to other molecules/vectors. Further, a vector is a vehicle that is used to transport the dye to one or more desired locations and may be targeted actively or passively. The use of dyes such as these to aid in visualizing certain medical phenomena is established. For example, certain dyes may be utilized to differentially highlight certain tissue types or structures, such as tumors. Such dyes may take advantage of particular properties of the tissues being highlighted.
[0018] Various approaches exist for developing agent, such as dyes, to highlight tumor tissue. For example, one approach, known as active targeting, targets tumor specific molecular targets, e.g. receptors, proteases, etc. (active targeting). Another approach, known as passive targeting, targets tumor morphology, e.g., leaky vasculature. Agents, i.e., dyes, developed using these types of approaches may be used to differentially highlight tumor structures. Such dyes may then be utilized in invasive procedures to allow a surgeon to visualize the extent of the tumor and to better facilitate removal of all tumor cells.
[0019] However, different types of tumors, subjects, or procedures may benefit from different dyes, i.e., different circumstances may call for different dyes. The number of potential suitable dyes, however, is vast and present techniques utilize subjective assessment which is qualitative in nature to screen candidate dyes or use manual procedures to highlight areas of interest before quantification. The latter approach is also subjective as a person visually identifies area of interest for quantification. In addition, manual identification is also laborious and time consuming. Such subjective assessments are generally unsuitable for screening large numbers of candidate dyes and, further, do not facilitate making meaningful comparisons between the candidates dyes.
[0020] In addressing this issue, therefore, it may be desirable to provide a more quantitative assessment and to utilize automation where possible. With this in mind, reference is now made to FIG. 1 which depicts certain acts of one embodiment of such a method 10 . In the embodiment of the technique described in FIG. 1 , an operator accesses (block 20 ) an image 22 from a subject, such as a lab rat, administered a visualization agent, such as a suitable tumor specific dye, prior to the generation of the image 22 . For example, the subject may be injected with a compound or solution that includes a fluorescing dye that preferentially accumulates in angiogenic tissues, such as tumors. The subject may then be surgically opened to expose the likely tumor location and one or more images 22 generated of the site. In one embodiment, an infrared (IR) imager (such as a system suitable for near infrared (NIR) fluorescent intra-operative imaging) is used to obtain one or more images of the dye-stained tumor. Thus, the images 22 accessed by the operator may be IR, NIR, or other suitable images of one or more dye-stained tumors. Certain wavelengths, such as NIR wavelengths, may be useful where less autofluorescence of standard tissues is desired.
[0021] In one embodiment, an operator may visually inspect the image 22 to determine (block 24 ) if the image 22 depicts a tumor that is suitably or sufficiently labeled with dye. In such an embodiment, the operator may consider factors such as whether the dye highlights only the boundary of the tumor (i.e., the tumor margin), whether the dye extends beyond the tumor or tumor boundary to an unacceptable degree, as well as, other aspects of proper labeling. If the operator decides the depicted tumor is not suitably labeled, the operator may access a different image 22 . If the operator decides that the depicted tumor is suitably labeled, the operator may proceed to process the image 22 .
[0022] Once a suitable image 22 is identified, the operator may select (block 26 ) the dye-labeled tumor 28 in the displayed image 22 . For example, the operator may employ a mouse, touchpad, touchscreen, or other suitable point-and-select interface to select the tumor 28 , such as by “clicking” on the perceived center of the tumor using a mouse or other suitable selection input device. In other embodiments, selection of the tumor 28 may be automated or semi-automated, such as by employing thresholding or other algorithms that identify concentrations of the dye over a certain limit within the image 22 . In such embodiments, a tumor 28 may be tentatively identified based on the thresholding algorithms alone or potential tumors may be identified on the image 22 by the algorithm for further review and selection by an operator.
[0023] Once a tumor 28 is identified, one or more automated routines may be employed to detect (block 30 ) the boundary 32 of the tumor 28 . The routine 18 may detect the entire boundary 32 of the tumor 28 or only a portion of the boundary 32 , depending on the extent the dye highlights the boundary 32 of the tumor 28 . In one embodiment, this routine, as well as others discussed herein, is implemented using the IDL language and can be distributed using the IDL virtual machine.
[0024] In one embodiment, another automated routine may be employed to measure (block 34 ) one or more quantitative characteristics 36 of the boundary 32 . Examples of such boundary characteristics, as discussed in greater detail below, include average intensity, pixel intensity variance, number and relative length of boundary discontinuities, brightness ratio, average contrast, clearance rate, and so forth. The characteristics 36 of the boundary 32 may be reviewed or evaluated by an operator to evaluate or compare the efficacy of the dye in staining the tumor 28 . In addition, the characteristics 36 may be stored for later review or comparison. As will be appreciated, some of the steps depicted in the flow chart of FIG. 1 may be optional in various embodiments.
[0025] With the foregoing general discussion the following example is provided by way of illustration. Turning now to FIG. 2 , a screenshot 40 displaying an infrared image 22 is depicted. In this example, infrared image 22 depicts a tumor 28 within an organ 42 , such as the skin, kidney, spleen, liver, prostate, and so forth. If the image 22 is deemed to be unsuitable, such as due to insufficient staining of the tumor 28 , an operator may load a new image, such as using the “LOAD NEW” button 44 of the user input interface 46 . If, however, the image 22 is deemed suitable, the operator may select the tumor 28 from the image 22 , such as using a mouse, touchscreen, or other point-and-select device to select the center of the perceived tumor 28 . In one embodiment, the tumor selection process may be facilitated by the display of a circle 38 or other selection area that may be centered around a point selected by the operator or which may be moved by the operator to encompass the area deemed to show the tumor 28 . Alternatively, as noted above, automatic or semi-automatic processes may be employed, in lieu of operator input, to select the tumor 28 within the image 22 .
[0026] In certain embodiments, the image 22 may be processed prior to tumor selection and/or identification of the tumor boundary. For example, in one embodiment, the image 22 may be enhanced, such as by implementation of anisotropic smoothing and/or other pre-processing filters. In addition, in certain embodiments the image 22 may undergo contrast stretching and/or multi-stage binarization.
[0027] Once the tumor 28 is selected a computer-executed algorithm may automatically identify the tumor boundary 32 . In one embodiment, the tumor boundary 32 may be identified utilizing an intensity threshold. Pixels having an intensity greater than a set or threshold value may be determined to correspond to tumor tissue. In turn, those pixels determined to correspond to tumor tissue that have intensity values greater than a neighboring pixel in at least one direction may be determined to correspond to the boundary 32 of the tumor 28 . That is, those pixels which are stained (e.g., fluorescing) but which are adjacent to at least one other pixel that is not stained (e.g., non-fluorescing) above a certain threshold may be identified as corresponding to the boundary 32 of the tumor 28 .
[0028] In one embodiment, upon determination of the tumor boundary 32 , the circle 38 used to highlight the region having the tumor 28 may be warped to highlight the identified tumor boundary 32 , as depicted in the inset to FIG. 2 . For example, in one implementation, the tumor boundary 32 may be fitted using a generally annular or toroidal model, i.e., a doughnut or ring shaped model, which may be derived using the circle 38 used to highlight the region. Such an annular model may be suitable in implementations where the dye is generally expected to only highlight the peripheral region of the tumor, such as due to cellular death at the center of the tumor.
[0029] Turning now to the screenshot depicted in FIG. 3 , once the tumor boundary 32 is identified, a computer-executed algorithm may be employed to quantify one or more aspects of the tumor boundary 32 , such as by generating one or more boundary characteristics 36 , such as quantitative descriptors, of the tumor boundary 32 . An operator may review the boundary characteristics, such as to assess the performance of the fluorescent dye used in generating the specific image 22 under review, and/or the boundary characteristics may be stored for subsequent review or comparison.
[0030] In one embodiment, the algorithm employed may generate quantitative boundary characteristics 36 of one or more aspects of the tumor boundary 32 . For example, in one embodiment, a quantitative descriptor of the average brightness of the tumor boundary 32 may be measured by averaging the intensity values of those pixels determined to correspond to the tumor boundary 32 . Similarly, other measures of central tendency such as median and mode values, may be calculated based on the intensity values of those pixels determined to correspond to the tumor boundary 32 . These descriptors may then be stored or displayed for evaluation by a reviewer.
[0031] Other types of quantitative boundary characteristics 36 may also be calculated. For example, a quantitative descriptor of the variation of brightness of the tumor boundary 32 (e.g., the standard deviation of the pixel intensities for those pixels corresponding to the tumor boundary 32 ) may also be calculated. In addition, in some embodiments the quantitative boundary characteristics 36 may include the number of discontinuities or breaks 54 in the tumor boundary 32 , as well as, the length of each discontinuity 54 . For example, the length of each discontinuity 54 may be described by equation (1) as follows:
[0000]
L
disc
=
arc
length
of
the
discontinuity
*
100
360
%
(
1
)
[0000] where L disc , refers to the length of the discontinuity.
[0032] A further descriptor which may be quantified in certain embodiments is the squared average contrast. The squared average contrast may be described by equation (2) as follows:
[0000]
C
=
(
I
margin
I
background
)
2
(
2
)
[0000] where C refers to the squared average contrast, I margin refers to the average pixel intensity in the tumor boundary 32 , and I background refers to the average pixel intensity in the background region surrounding the tumor boundary 32 . In the depicted embodiment, the thickness of the background region used in quantifying and generating characteristics 36 such as the squared average contrast may be adjusted by the operator, such as via slider 58 of the user interface screen. Adjusting the amount or thickness of the region designated as background may vary the sensitivity and/or accuracy of the generated quantitative boundary characteristics 36 . In implementations where different dyes are ranked with respect to each other, it may be useful to keep the thickness of background region constant. In one embodiment, the background region thickness is set to a default of forty-one pixels.
[0033] Yet another boundary characteristic 36 that may be quantified in certain embodiments may be rotational contrast, i.e., the ratio of the rotational average of the tumor boundary pixel intensity to the rotational average of the background pixel intensities surrounding the tumor boundary 32 . In such an embodiment, the rotational average may be considered the average of the average brightness along the radius around 360 degrees. The rotational contrast may be described by equation (3) as follows:
[0000]
C
rotational
=
(
I
rot_margin
I
rot_background
)
2
(
3
)
[0000] Wherein C rotational refers to the rotational contrast, I rot — margin refers to the rotational average pixel intensity of the tumor boundary 32 , and I rot — background refers to the rotational average pixel intensity of the background region surrounding the tumor boundary 32 . Thus, in one such embodiment where rotational contrast is calculated, the tumor is modeled as a circular region and the highlighted region, i.e., the automatically identified boundary, is considered. In such an embodiment, higher values may be awarded to those dyes that partially illuminate the tumor, i.e., which are limited to the boundary region without highlighting the tumor interior. As will be appreciated, some or all of these quantitative descriptors, and/or different combinations of these descriptors, may be employed in different embodiments.
[0034] With the foregoing in mind, it should be appreciated that quantitative boundary characteristics 36 may be generated in a variety of contexts for different dyes, tumor types, points in time, lab animal types, and so forth. These quantitative descriptors may be used to select or grade dyes based on their suitability in different clinical contexts or to select dyes for further testing.
[0035] For example, in one embodiment, an operator may process a plurality of images as described herein. In such an embodiment, the operator may access (block 20 ) a plurality of images 22 , such as IR images, of tumors suitably stained with one or more fluorescent or other suitable dyes. The operator may exclude (block 24 ) those images which exhibit poor or unsuitable staining characteristics from further consideration. In one embodiment, the operator may process the remaining images to select (block 26 ) the respective tumors 28 within each image 22 . One or more automated routines may be executed to identify (block 30 ) the boundaries of each selected tumor 28 . As will be appreciated, the identification of tumor boundaries may occur in a batch processing of the images 22 or may be performed on each image 22 separately as the tumor 28 is selected. The identification of tumor boundaries may be performed contemporaneous with or subsequent to the execution of other routines to enhance the tumor boundaries, such as routines for implementing one or more anisotropic smoothing operations, contrast stretching, multi-stage binarization, and so forth.
[0036] One or more automated routines may be implemented to determine (block 34 ) characteristics 36 , such as quantitative measures, of each tumor boundary 32 . In certain embodiments, the quantitative descriptors may be standardized (block 80 ) or normalized for each tumor boundary 32 . For example, such standardization processes may account for variations in brightness and/or other image property differences. In one such embodiment, the operator may select a dark area in the respective image 22 . The routine calculating the boundary characteristics 36 may in turn use the intensity of the selected dark region (or an average of the intensity in the selected dark region) to normalize or otherwise adjust for differences in brightness between images 22 . In this way, differences in image brightness may be normalized by establishing a base darkness level for each image which may be used to scale other intensity levels in the respective image 22 .
[0037] In this manner, comparable quantitative boundary characteristics 36 may be generated for the respective tumor boundaries 32 observed in each processed image 22 . The boundary characteristics 36 may then be ranked (block 82 ), either automatically or by a reviewer, by one or more of the characteristics, allowing a reviewer to select (block 86 ) which dyes 84 performed best in different medical contexts, such as in different animal models, on different tumor types, based on clearance rate, and so forth. Selected dyes may then undergo further testing and/or may be selected for use in invasive procedures, such as in surgical procedures for tumor removal. In this way, a reviewer may select dyes based on quantitative measurements, as opposed to a subjective visual assessment. As will be appreciated, the order in which different steps illustrated in FIG. 4 may vary. For example, the depicted standardization step may be performed prior or subsequent to when depicted.
[0038] Referring now to FIG. 5 , a block diagram depicting a processor-based system 98 , such as a computer or workstation, for use in accordance with the present disclosure is provided. The depicted processor-based system 98 includes a microprocessor or CPU 100 capable of executing routines such as those described herein, i.e., routines for tumor boundary detection and computation of quantitative characteristics of such boundaries. Such routines, as well as image data to be processed by such routines and the output (i.e., results) of such routines, may be stored in a local or remote mass storage device 102 , such as a hard disk, solid state memory component, optical disk, and so forth. In addition, the processor based system. Further, the processor-based system 98 may access routines or image data for processing via a network connection 106 , such as a wired or wireless network connection. Such routines and/or image data may be temporarily stored in RAM 104 prior to processing by the CPU 100 .
[0039] Accessed or processed image data, as well as the boundary characteristics described herein, may be displayed on a display 108 for review by an operator. In addition, the processor-based system 98 may include one or more input devices 110 , such as a keyboard, mouse, touchscreen, touchpad, and so forth, allowing an operator to access image data, select images for processing, select tumors, within images, review results, and so forth. In this manner, an operator may review the outputs of the disclosed techniques and provide inputs to further operation of the disclosed techniques.
[0040] The identification of tumor boundaries and quantification of dyes used to highlight the tumor boundaries, as described herein, provides a useful tool to the medical and scientific community. For instance, with the methods outlined above a number of dyes can be analyzed and the data obtained stored to allow comparisons between the dyes to determine the best dyes in general and for specific tumor types. In addition, the efficacy of a dye can be shown over multiple tumor types. Possessing quantitative measurements introduces reliability and reproducibility in assessing the dyes, removing the subjectivity normally involved.
[0041] Another benefit of the methods is the automatic detection and marking of the tumor boundary, once the operator selects an area of interest, provides an invaluable tool in a dynamic environment such as a surgical setting. Applying these methods to imaging systems used in open surgery would improve the ability of the surgeon to remove the complete tumor while sparing as much of the normal tissue in the patient as possible.
[0042] Technical effects of the invention include the automated or semi-automated identification of tumor boundaries and the quantification of dye efficacy in staining the boundaries. Such measures may allow the analysis and comparison of multiple dyes in a quantitative, objective manner.
[0043] While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. | The present disclosure generally relates to systems and methods for identifying the boundaries of tumors and assessing quantitatively the ability of dyes to highlight a tumor's boundary. In accordance with these methods and systems, images are taken of subjects administered agents labeled with dyes. After accessing the images, tumors are selected and routines employed to both identify the boundaries of the tumors, as well as, to quantify various aspects of the tumor boundaries. From these quantifiable descriptors the performances of the various dyes to highlight the boundaries of tumors are evaluated. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present document is based on and claims priority to U.S. Provisional Application Ser. No.: 61/970864, filed Mar. 26, 2014, and U.S. Provisional Application Ser. No.: 62/036572, filed Aug. 12, 2014, which are incorporated herein by reference in their entirety.
BACKGROUND
[0002] In many hydrocarbon well applications, wellbores are drilled into a desired hydrocarbon-bearing formation via a variety of drilling systems. For example, drilling operations may be performed with drill strings including a variety of bottom hole assemblies constructed to drill a desired wellbore. In some applications, rotary steerable drilling systems may be used to control the trajectory of the wellbore being drilled. This facilitates the drilling of deviated, e.g. horizontal, wellbores. During drilling, stabilizers and other drilling components of the bottom hole assembly may be subjected to substantial abrasion. This abrasion can be detrimental to the life of the stabilizer or other bottom hole assembly components. Depending on the application, stabilizers may be used with steerable drilling systems to provide contact points with the wellbore wall to facilitate steering. Additionally, stabilizers known as string stabilizers may be used farther up the bottom hole assembly of the drill string to support tools, to reduce shock and vibration, and to reduce stick-slip.
SUMMARY
[0003] In general, a system and methodology are provided to facilitate the dependable, long-lasting use of a downhole component coupled into a drill string. In some embodiments, the downhole component may comprise a stabilizer having a plurality of blades extending outwardly from a body, e.g. sleeve. Various features of the downhole component enhance the usefulness and dependability of the downhole component. Examples of such features comprise uniquely shaped surfaces; materials with a desired hardness, toughness, and impact strength; and/or wear protection elements incorporated into the downhole component.
[0004] However, many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Certain embodiments of the disclosure will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements. It should be understood, however, that the accompanying figures illustrate the various implementations described herein and are not meant to limit the scope of various technologies described herein, and:
[0006] FIG. 1 is a side view of an example of a stabilizer, e.g. an abrasion resistant stabilizer, mounted in a drill string, according to an embodiment of the disclosure;
[0007] FIG. 2 is a cross-sectional view of an example of a stabilizer to illustrate mounting of the stabilizer on a collar of a drill string, according to an embodiment of the disclosure;
[0008] FIG. 3 is a side view of another example of a stabilizer, according to an embodiment of the disclosure;
[0009] FIG. 4 is a graphical representation illustrating plots of pull force versus taper angle for varying hole inclinations, according to an embodiment of the disclosure;
[0010] FIG. 5 is a side view of another example of a stabilizer, according to an embodiment of the disclosure;
[0011] FIG. 6 is an orthogonal view of an abrasion resistant sleeve which may be used with a variety of downhole components, including stabilizers, according to an embodiment of the disclosure;
[0012] FIG. 7 is an illustration of a drill string having a plurality of downhole components protected with abrasion resistant sleeves and/or other abrasion resistant features, according to an embodiment of the disclosure;
[0013] FIG. 8 is an illustration of another example of an abrasion resistant component in the form of a rotary valve system, according to an embodiment of the disclosure; and
[0014] FIG. 9 is an illustration of another example of an abrasion resistant component in the form of an impeller which may be used in a variety of downhole components, according to an embodiment of the disclosure.
DETAILED DESCRIPTION
[0015] In the following description, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.
[0016] With respect to certain embodiments of the present disclosure, a system and methodology are described for facilitating a drilling operation which employs a stabilizer or stabilizers on a drill string. The stabilizer (or stabilizers) comprises an end face or end faces having shallower slopes instead of steep slopes. Steep slopes can sometimes cause the bottom hole assembly to get stuck on a ledge or other obstruction along the wellbore. In some applications, shallower slopes may be employed on both leading and trailing faces. In other applications, a shallower slope may be employed on one of the faces. For example, the shallower slope may be located on a trailing face of the stabilizer to reduce the risk of hanging-up the bottom hole assembly on a ledge or other obstruction while tripping out of the hole. It should be noted the shallower slopes and/or the relatively shallower slope on the trailing face may be employed on a variety of parts, components or entire tools.
[0017] In some applications, the stabilizer may be constructed with a shallow sloped trailing face and a leading face having a steeper slope. The steeper leading face moves the crown (contact point) of the stabilizer forward toward the drill bit. By moving the crown of the stabilizer toward the drill bit, the dogleg capability of the drilling system may be substantially increased.
[0018] Referring generally to FIG. 1 , an example of a downhole component 10 in the form of a stabilizer mounted in a drilling system 12 is illustrated. However, downhole component 10 may comprise a variety of parts, components or entire tools. In this embodiment, drilling system 12 comprises a drill string 14 having a drill string collar 16 and a drill bit 18 . The stabilizer 10 is mounted on drill string collar 16 and comprises a body 20 , e.g. a tubular body, having an interior surface 22 and an exterior surface 24 . The interior surface 22 faces inwardly toward the drill string collar 16 and the exterior surface 24 faces in a radially outward direction. The stabilizer 10 further comprises a plurality of blades 26 which extend outwardly from exterior surface 24 . The blades 26 extend along at least a portion of the longitudinal length of body 20 and are separated circumferentially by flow channels 28 . In some applications, the blades 26 are arranged helically and thus provide generally helical flow channels 28 therebetween. The flow channels 28 allow flows of fluid to move longitudinally past the stabilizer 10 along drill string 14 .
[0019] The longitudinal ends of blades 26 establish a leading face 30 and a trailing face 32 . Generally, the leading face 30 is on the downhole end toward drill bit 18 and the trailing face 32 is on the uphole end of blades 26 . The leading face 30 is oriented at a leading end angle 34 with respect to exterior surface 24 , and trailing face 32 is oriented at a trailing end angle 36 with respect to exterior surface 24 . Depending on the application, the leading face 30 and/or trailing face 32 may have a shallow slope in the form of a relatively small leading end angle 34 and/or trailing end angle 36 , respectively. In the embodiment illustrated in FIG. 1 , the leading face 30 has a relatively steep taper, e.g. a leading end angle 34 of 70° or greater. In this embodiment, the trailing face 32 has a shallow taper, e.g. a trailing end angle 36 of 45° or less. In some applications, the shallow taper may comprise a trailing end angle 36 of 30° or less.
[0020] As illustrated, some embodiments may utilize a substantially shallower taper on the trailing face 32 relative to a steeper taper on the leading face 30 . Additionally, the leading face 30 and/or trailing face 32 may be constructed with the leading end angle 34 and the trailing end angle 36 , respectively, formed as compound angles. In other words, one or both of the leading end angle 34 and/or trailing end angle 36 may be formed with a plurality of differently angled slopes.
[0021] The stabilizer 10 may be mounted on drill string collar 16 of drilling system 12 via a variety of structures and techniques. An example of such a structure and technique is illustrated in FIG. 2 . In this embodiment, the interior surface 22 has an internal diameter profile 38 , e.g. an abutment, located to facilitate construction of a lengthened stabilizer body 20 . The profile 38 is oriented for engagement with a shoulder 40 of drill string collar 16 . Additionally, the stabilizer 10 may be threadably engaged with and tightened against shoulder 40 via a threaded region 42 on collar 16 and a corresponding threaded region 44 along the interior of body 20 . In this example, the drill string collar also may comprise a bit box 46 for engagement with drill bit 18 . The overall arrangement facilitates construction of a longer stabilizer 10 to accommodate the longer, shallower slopes of the face or faces 30 , 32 . For example, profile 38 acts against the collar shoulder 40 at an internal location which allows the stabilizer to be lengthened by enabling the blades 26 to extend over this internal location.
[0022] Referring generally to FIG. 3 , another embodiment of the stabilizer 10 is illustrated. In this embodiment, the leading face 30 and the trailing face 32 of blades 26 both have a relatively shallow slope. In other words, the leading end angle 34 and the trailing end angle 36 are relatively small. For example, the shallow slope of the leading face 30 and the trailing face 32 may have leading end angle 34 and trailing end angle 36 , respectively, of 45° or less. In some applications, the shallow taper may comprise both a leading end angle 34 and a trailing end angle 36 of 30° or less. In some applications, a shallower taper on the leading face 30 can limit steerability and dogleg capability. To increase dogleg capability, the slope taper at the leading face 30 may be steeper and the slope taper at the trailing face 32 may be relatively shallower.
[0023] As illustrated by the graph of FIG. 4 , the face taper angle has an effect on the force applied to the drill string, e.g. the pull force, to overcome friction associated with an obstruction, e.g. a ledge. FIG. 4 illustrates examples of pull force used to overcome friction for a variety of borehole inclinations and face taper angles. As illustrated, the pull force used to move stabilizer 10 past the obstruction decreases as the face taper angle decreases. FIG. 4 provides a graphical overview of this relationship for a variety of wellbore types.
[0024] Referring generally to FIG. 5 , another embodiment of the stabilizer 10 is illustrated. In this embodiment, cutting features 48 are added along the slopes, e.g. the shallow slopes, of leading face 30 and/or trailing face 32 . The cutting features 48 may comprise cutters, such as polycrystalline diamond (PDC) cutters, formed of hard material and positioned along the sloped faces 30 and/or 32 . The cutting features may be oriented to cut away obstructions, such as ledges resulting from washouts, encountered along the wellbore. In some applications, the cutting features may be applied to a non-magnetic stainless steel substrate.
[0025] According to other and/or additional aspects of the present disclosure, various downhole components 10 , e.g. stabilizers, other components, or entire tools, may be constructed in a manner providing resistance to abrasion in well related applications and non-well related applications. For example, the technique may provide increased abrasion resistance in a downhole component deployed in a drilling bottom hole assembly. In some applications, a sleeve is mounted to or constructed as part of the downhole component. The sleeve is formed of materials having suitable hardness, toughness and impact strength, such as materials comprising a tungsten carbide matrix. By way of example, the tungsten carbide matrix may comprise tungsten carbide particles in a suitable matrix, e.g. cobalt, and processed according to appropriate powder metallurgy techniques to form a metal matrix composite referred to herein as tungsten carbide matrix. In some applications, the sleeve may be formed primarily of tungsten carbide matrix.
[0026] In other applications, the sleeve may be formed of a suitable composite material with portions comprising the tungsten carbide mixture. By way of example, the portions of hard tungsten carbide mixture may be bonded to steel or to another material having suitable toughness and impact strength. However, various other materials and material combinations may be used to form the sleeve. The composition of the tungsten carbide matrix also may be adjusted to accommodate various loading effects, thermal effects, and/or other effects likely to be experienced by the sleeve in a given application. The sleeve also may employ a plurality of wear protection elements. Depending on the application, the wear protection elements may be used with or incorporated into a variety of other components. It should be noted the suitable composite material and the plurality of wear protection elements may be used in a variety of parts, components or entire tools.
[0027] In some embodiments, the abrasion resistant components facilitate drilling operations and may be in the form of a stabilizer (or stabilizers) having an abrasion resistant sleeve. One or more of the stabilizers may be employed at various positions along a drill string and in combination with various types of drill string components, such as bottom hole assembly components. In addition to their usefulness in stabilizers, the abrasion resistant sleeves and/or other abrasion resistant features may be used in combination with directional drilling components, measurement-while-drilling components, and logging-while-drilling components. However, the abrasion resistant sleeves and/or other abrasion resistant features also may be used with a variety of other components, such as bottom hole assembly components. Examples include wear bands, kicker plates, filters and screens, telemetry modulators, impellers, turbine blades, cutter blocks for hole enlargement tools, stabilizer blocks for variable gauge stabilizers, and/or other downhole components.
[0028] Depending on the parameters of a given application, the abrasion resistant sleeves may comprise a suitable material or materials, e.g. a composite material having portions formed of tungsten carbide matrix. In some applications, the entire abrasion resistant sleeve may be made of tungsten carbide matrix. The sleeve also may be provided with additional wear protection elements, such as polycrystalline diamond compacts and thermally stable polycrystalline components. The polycrystalline diamond compacts and the thermally stable polycrystalline components can be constructed in a variety of different shapes to provide additional, high abrasion resistance with respect to the sleeves or other components. The additional wear protection elements also may be positioned in optimized patterns or arrangements to help reduce the erosion and abrasive wear.
[0029] Referring again to FIG. 1 , the component 10 , e.g. stabilizer 10 , may be formed as an abrasion resistant component 10 . The abrasion resistant stabilizer 10 (or other component 10 ) may similarly be mounted on drill string collar 16 . As with embodiments described above, the abrasion resistant stabilizer 10 may comprise the plurality of blades 26 which extend outwardly from exterior surface 24 . Also, the abrasion resistant stabilizer 10 may be used in combination with drill bit 18 and/or in combination with other drill string components.
[0030] As illustrated in FIG. 6 , the abrasion resistant stabilizer 10 may comprise an abrasion resistant sleeve 50 . The abrasion resistant sleeve 50 may be constructed as the entire abrasion resistant stabilizer 10 , or the abrasion resistant sleeve 50 may be mounted to or incorporated into the stabilizer 10 . In this example, the abrasion resistant sleeve 50 is formed at least in part from tungsten carbide matrix and comprises a plurality of additional wear protection elements 52 . By way of example, the additional wear protection elements 52 may comprise polycrystalline diamond compacts and/or thermally stable polycrystalline components.
[0031] In this stabilizer example, sleeve 50 may be formed with stabilizer blades 26 and the wear protection elements 52 may be mounted on or incorporated into the stabilizer blades 26 . By way of example, the wear protection elements 52 may comprise polycrystalline diamond compact elements 54 and/or thermally stable polycrystalline elements 56 . The wear protection elements 52 may be mounted along a lead edge 58 progressing up along each stabilizer blade 26 and in an arrangement which reduces wear on the lead edge 58 . Additionally, the wear protection elements 52 may be arranged to reduce transversal wear patterns.
[0032] In the embodiment illustrated, the wear protection elements 52 comprise polycrystalline diamond compact elements 54 constructed as high rake cutters provided along the leading edges 58 . In some applications, the polycrystalline diamond compact elements 54 are arranged in rows along the leading edge 58 . In this example, the blades 26 also comprise thermally stable polycrystalline elements 56 positioned to provide additional wear protection. It should be noted, however, the wear protection elements 52 may be formed from a variety of hardened materials. The wear protection elements 52 also may have various shapes and may be arranged in different patterns depending on the environment, the application, and/or the type of abrasion resistant component 10 , e.g. stabilizer 10 . In some applications, sleeve 50 may comprise threaded regions 59 (or other suitable connector mechanisms) at its longitudinal ends to facilitate attachment to adjacent well string components.
[0033] Referring generally to FIG. 7 , other embodiments of abrasion resistant components 10 are illustrated. In this example, the abrasion resistant components 10 are assembled into drill string 14 deployed in a wellbore 60 . The abrasion resistant components 10 incorporate abrasion resistant sleeves 50 which provide the components with high abrasion resistance. Again, the abrasion resistant sleeves 50 may be formed in whole or in part of tungsten carbide matrix. In some applications, the abrasion resistant sleeves 50 may be used to protect antennas 62 of, for example, measurement-while-drilling components and/or logging-while-drilling components. The abrasion resistant sleeves 50 also may be used in conjunction with, e.g. as part of, stabilizers to form abrasion resistant stabilizer components 10 as described above. The abrasion resistant sleeves 50 in these embodiments may again comprise or be combined with a variety of the wear protection elements 52 formed of various hard materials. The wear protection elements 52 may be attached to sleeve 50 via suitable attachment mechanisms, such as threaded attachment mechanisms, weldments, independent fasteners, and/or other suitable attachment mechanisms.
[0034] As illustrated in FIG. 8 , the abrasion resistant component 10 also may comprise a variety of rotary valves 64 in which hardened, wear protection elements 52 are combined with various components of the valve 64 . In some downhole applications, the rotary valve 64 is combined with a torque impeller 66 , and the wear protection elements 52 may be mounted on or formed with impeller blades and/or other system components to provide a high resistance to abrasion from, for example, sand and other particulates.
[0035] As illustrated in FIG. 9 , for example, a variety of impellers 66 may incorporate wear protection elements 52 along impeller blades 68 and/or at other portions of the impeller 66 to provide resistance to abrasion. As discussed above, however, the abrasion resistant sleeves 50 and/or wear protection elements 52 may be used with many types of components to construct abrasion resistant components 10 . The abrasion resistant sleeves 50 and/or wear protection elements 52 may be combined with wear bands, kicker plates, filters and screens, telemetry modulators, turbine blades, cutter blocks for hole enlargement tools, stabilizer blocks for variable gauge stabilizers, and/or other downhole components.
[0036] Depending on the application, the wear resistant components 10 may have a variety of configurations comprising other and/or additional components. For example, the wear resistant components 10 may comprise a variety of rotary steerable system components such as pads, e.g. actuator pads, or kickers. In stabilizer applications, the shape and structure of the stabilizer body and stabilizer blades may vary in size and configuration depending on the parameters of a given application and environment. Similarly, a variety of materials may be used to construct the wear protection elements 52 . Additionally, the wear protection elements 52 may be combined with many types of abrasion resistant sleeves 50 and/or other types of abrasion resistant components in well applications and non-well applications. In some applications, the sleeve 50 may utilize features, e.g. tongue and groove features, to facilitate making-up the connection with adjacent components.
[0037] Although a few embodiments of the disclosure have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims. | A technique facilitates the dependable, long-lasting use of a downhole component coupled into a drill string. In some applications, the downhole component comprises a stabilizer having a plurality of blades extending outwardly from a body, e.g. sleeve. Various features of the downhole component enhance the usefulness and dependability of the downhole component. Examples of such features comprise uniquely shaped surfaces; materials with a desired hardness, toughness, and impact strength; and/or wear protection elements incorporated into the downhole component. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. provisional application Ser. No. 60/660,249, filed Mar. 10, 2005, entitled “System and Method for Multimodal Content Delivery in Interactive Response Systems,”, which is also incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to telecommunications in general, and, more particularly, to coordinating the delivery of multiple content streams from an interactive voice response system.
BACKGROUND OF THE INVENTION
Many enterprises employ an interactive voice response (IVR) system that handles calls from telecommunications terminals. An interactive voice response system typically presents a hierarchy of menus to the caller, and prompts the caller for input to navigate the menus and to supply information to the IVR system. For example, a caller might touch the “3” key of his terminal's keypad, or say the word “three”, to choose the third option in a menu. Similarly, a caller might specify his bank account number to the interactive voice response system by inputting the digits via the keypad, or by saying the digits. In many interactive voice response systems the caller can connect to a person in the enterprise by either selecting an appropriate menu option, or by entering the telephone extension associated with that person.
FIG. 1 depicts telecommunications system 100 in accordance with the prior art. Telecommunications system 100 comprises telecommunications network 105 , private branch exchange (PBX) 110 , and interactive voice response system 120 , interconnected as shown.
Telecommunications network 105 is a network such as the Public Switched Telephone Network [PSTN], the Internet, etc. that carries a call from a telecommunications terminal (e.g., a telephone, a personal digital assistant [PDA], etc.) to private branch exchange 110 . A call might be a conventional voice telephone call, a text-based instant messaging (IM) session, a Voice over Internet Protocol (VoIP) call, etc.
Private branch exchange (PBX) 110 receives incoming calls from telecommunications network 105 and directs the calls to interactive voice response (IVR) system 120 or to one of a plurality of telecommunications terminals within the enterprise, depending on how private branch exchange 110 is programmed or configured. For example, in an enterprise call center, private branch exchange 110 might comprise logic for routing calls to service agents' terminals based on criteria such as how busy various service agents have been in a recent time interval, the telephone number called, and so forth. In addition, private branch exchange 110 might be programmed or configured so that an incoming call is initially routed to interactive voice response (IVR) system 120 , and, based on caller input to IVR system 120 , subsequently redirected back to PBX 110 for routing to an appropriate telecommunications terminal within the enterprise. Private branch exchange (PBX) 110 also receives outbound signals from telecommunications terminals within the enterprise and from interactive voice response (IVR) system 120 , and transmits the signals on to telecommunications network 105 for delivery to a caller's terminal.
Interactive voice response (IVR) system 120 is a data-processing system that presents one or more menus to a caller and receives caller input (e.g., speech signals, keypad input, etc.), as described above, via private branch exchange 110 . Interactive voice response system (IVR) 120 is typically programmable and performs its tasks by executing one or more instances of an IVR system application. An IVR system application typically comprises one or more scripts that specify what speech is generated by interactive voice response system 120 , what input to collect from the caller, and what actions to take in response to caller input. For example, an IVR system application might comprise a top-level script that presents a main menu to the caller, and additional scripts that correspond to each of the menu options (e.g., a script for reviewing bank account balances, a script for making a transfer of funds between accounts, etc.).
A popular language for such scripts is the Voice extensible Markup Language (abbreviated VoiceXML or VXML). The Voice extensible Markup Language is an application of the eXtensible Markup Language, abbreviated XML, which enables the creation of customized tags for defining, transmitting, validating, and interpretation of data between two applications, organizations, etc. The Voice extensible Markup Language enables dialogs that feature synthesized speech, digitized audio, recognition of spoken and keyed input, recording of spoken input, and telephony. A primary objective of VXML is to bring the advantages of web-based development and content delivery to interactive voice response system applications.
FIG. 2 depicts an exemplary Voice extensible Markup Language (VXML) script (also known as a VXML document or page), in accordance with the prior art. The VXML script, when executed by interactive voice response system 120 , presents a menu with three options; the first option is for transferring the call to the sales department, the second option is for transferring the call to the marketing department, and the third option is for transferring the call to the customer support department. Audio content (in particular, synthesized speech) that corresponds to text between the <prompt> and </prompt> tags is generated by interactive voice response system 120 and transmitted to the caller.
SUMMARY OF THE INVENTION
As video displays become ubiquitous in telecommunications terminals, it can be advantageous to deliver video content to a telecommunications terminal during a call with an interactive voice response (IVR) system, in addition to audio content. For example, a user of a telecommunications terminal who is ordering apparel via an IVR system might receive a video content stream related to a particular item (e.g., depicting a model who is wearing the item, depicting the different available colors for the item, etc.). Furthermore, in some instances it might be desirable to deliver an audio content stream (e.g., music, news, etc.) to the user, perhaps during silent periods in the call, or perhaps as background audio throughout the entire call.
The illustrative embodiment of the present invention enables an IVR system to deliver content streams of various media types (e.g., video, audio, etc.) to telecommunications terminals via the addition of extensions to the Voice extensible Markup Language (VXML) standard. In addition, the illustrative embodiment provides VXML extensions that enable an IVR system script to specify the playback order, timing, and coordination of multiple content streams (e.g., whether an audio stream and a video stream should be played back concurrently or serially; whether a particular content stream should finish before playback of another content stream commences; whether a content stream that is currently playing should be stopped and supplanted with another content stream, etc.).
The illustrative embodiment comprises: (a) receiving a list of one or more identifiers at a thread of an interactive voice response system, (i) wherein each of the identifiers is associated with one of a plurality of content streams, (ii) wherein each of the content streams has one or more of a plurality of media types, (iii) wherein the list specifies a playback order for the content streams, and (iv) wherein the thread is associated with one of the media types T and with a call that involves the interactive voice response system and a telecommunications terminal; and (b) executing in the thread a command for initiating delivery of one of the content streams S to the telecommunications terminal, (i) wherein the content stream S has the media type T, and (ii) wherein the time τ at which delivery of the content stream S begins is based on the playback order.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts telecommunications system 100 in accordance with the prior art.
FIG. 2 depicts an exemplary Voice extensible Markup Language (VXML) script, in accordance with the prior art.
FIG. 3 depicts telecommunications system 300 in accordance with the illustrative embodiment of the present invention.
FIG. 4 depicts an exemplary Voice extensible Markup Language (VXML) script, in accordance with the illustrative embodiment of the present invention.
FIG. 5 depicts an audio/video channel timing diagram that corresponds to the VXML script of FIG. 4 , in accordance with the illustrative embodiment of the present invention.
FIG. 6 depicts a flowchart of the salient tasks of interactive voice response system 320 , as shown in FIG. 3 , in accordance with the illustrative embodiment of the present invention.
FIG. 7 depicts a flowchart of the salient tasks of a thread that is spawned at task 680 of FIG. 6 , in accordance with the illustrative embodiment of the present invention.
DETAILED DESCRIPTION
FIG. 3 depicts telecommunications system 300 in accordance with the illustrative embodiment of the present invention. Telecommunications system 300 comprises telecommunications network 105 , private branch exchange (PBX) 310 , interactive voice response system 320 , content server 330 , and content database 340 , interconnected as shown.
Private branch exchange (PBX) 310 provides all the functionality of private branch exchange (PBX) 110 of the prior art, and is also capable of receiving streamed content (e.g., audio, video, multimedia, etc.) from content server 330 , of forwarding streamed content on to telecommunications network 105 for delivery to a caller's terminal, and of transmitting signals related to streamed content to content server 330 . Furthermore, in addition to conventional telephony-based signaling and voice signals, private branch exchange 310 is also capable of transmitting and receiving Internet Protocol (IP) data packets, Session Initiation Protocol (SIP) messages, Voice over IP (VoIP) traffic, and stream-related messages (e.g., Real Time Streaming Protocol [RTSP] messages, etc.) to and from IVR system 320 . It will be clear to those skilled in the art, after reading this specification, how to make and use private branch exchange (PBX) 310 .
Interactive voice response system 320 provides all the functionality of interactive voice response system 120 of the prior art, and is also capable of transmitting commands to content server 330 (e.g., starting playback of a content stream, stopping playback of the content stream, queueing another content stream, etc.) and of receiving information from content server 330 (e.g., an indication that playback of a content stream has begun, an indication that playback of a content stream has completed, etc.). It will be clear to those skilled in the art, after reading this specification, how to make and use interactive voice response system 320 .
Content server 330 is capable of retrieving content from content database 340 , of buffering and delivering a content stream to a calling terminal via private branch exchange 310 , of receiving commands from interactive voice response (IVR) system 320 (e.g., to start playback of a content stream, to queue another content stream, etc.), of transmitting status information to interactive voice response (IVR) system 310 , and of generating content (e.g., dynamically generating a video of rendered text, etc.) in well-known fashion. It will be clear to those skilled in the art, after reading this specification, how to make and use content server 330 .
Content database 340 is capable of storing a plurality of multimedia content (e.g., video content, audio content, etc.) and of retrieving content in response to commands from content server 330 , in well-known fashion. It will be clear to those skilled in the art, after reading this specification, how to make and use content database 340 .
As will be appreciated by those skilled in the art, some embodiments of the present invention might employ an architecture for telecommunications system 300 that is different than that of the illustrative embodiment (e.g., IVR system 320 and content server 330 might reside on a common server, etc.). It will be clear to those skilled in the art, after reading this specification, how to make and use such alternative architectures.
FIG. 4 depicts an exemplary Voice Extensible Markup Language (VXML) script, in accordance with the illustrative embodiment of the present invention. The script is the same as the script of FIG. 2 of the prior art, with the addition of lines of code depicted in boldface. As shown in FIG. 4 , the script now contains prompts that are audio and video content streams, in addition to speech prompts. In particular, the menu presentation comprises, in addition to speech: a video representation of the menu choices, an animated logo (e.g., a corporate logo, etc.), and an audio jingle. Furthermore, when the user selects choice 1 (sales), interactive voice response (IVR) system 310 delivers an audiovisual stream “demo.3gp,” an animated chart (e.g., an animated pie chart, etc.), an audio stream “jingle2.mp3,”, and an audiovisual stream “trailer.3gp.”
As shown in FIG. 4 , the illustrative embodiment provides various extensions to the VXML standard. First, a prompt can specify its particular media type(s) (e.g., audio-only, video-only, audiovisual, etc.). Second, prompts that include video can include a Boolean persist attribute that indicates whether the video should remain active until the next video prompt is encountered in the application. When the persist attribute for a video prompt is true, the VXML interpreter will proceed to the next prompt once the video has started; conversely, when the persist attribute for a video prompt is false (or no persist attribute is specified, in accordance with the illustrative embodiment), the VXML interpreter will not proceed to the next prompt until the video prompt has finished. As will be appreciated by those skilled in the art, although in the illustrative embodiment a persist attribute of true results in the VXML interpreter waiting for the video prompt to finish before proceeding to any subsequent prompt (i.e., video or non-video), in some embodiments the VXML interpreter might proceed to a subsequent non-video prompt before the video prompt has finished.
The illustrative embodiment thus enables a script to specify the manner in which multiple prompts should be presented via the order in which the prompts are enumerated, via the values of the persist attributes, and via the order and duration of interlaced prompt types.
FIG. 5 depicts a timing diagram of the audio and video channels for a call that is handled by the VXML script of FIG. 4 , in accordance with the illustrative embodiment of the present invention. At the start of the call, the synthesized speech of the menu is played concurrently with a video version of the menu, and then audio stream jingle 1 is played concurrently with the video of animatedLogo. Subsequently, after the caller has selected an option from the menu, the script: plays the audio and video streams of source demo concurrently; presents an animated chart in place of the video portion of demo while the audio portion of demo is still playing; plays audio stream jingle 2 concurrently with the animated chart after playback of demo has finished; and plays the audio and video streams of source trailer concurrently after jingle 2 has finished.
FIG. 6 depicts a flowchart of the salient tasks of interactive voice response (IVR) system 320 , in accordance with the illustrative embodiment of the present invention. It will be clear to those skilled in the art which tasks depicted in FIG. 6 can be performed simultaneously or in a different order than that depicted.
At task 610 , an incoming call is received at interactive voice response system 320 , in well-known fashion.
At task 620 , interactive voice response (IVR) system 320 assigns an instance of an appropriate IVR system application to the incoming call, in well-known fashion. As will be appreciated by those skilled in the art, although in the illustrative embodiments an instance of an IVR system application handles one incoming call at a time, in some other embodiments of the present invention an application instance might handle a plurality of calls concurrently.
At task 630 , interactive voice response (IVR) system 320 begins executing the IVR application instance, in well-known fashion.
At task 640 , interactive voice response (IVR) system 320 checks whether the current command to be executed in the IVR application instance initiates delivery of a content stream S to the calling telecommunications terminal. If so, execution continues at task 660 , otherwise, execution proceeds to task 650 .
At task 650 , interactive voice response (IVR) system 320 checks whether the IVR application instance's execution has completed. If so, execution continues back at task 610 for the next incoming call; otherwise, execution proceeds to task 690 .
At task 660 , interactive voice response (IVR) system 320 constructs an ordered list L of content stream identifiers from the block of consecutive <prompt>s that starts at the current command. For example, in the script of FIG. 4 , the block of consecutive <prompt>s in the <menu> block might correspond to ordered list:
L =(menuVideo1, speech1, animatedLogo.gif, jingle1.mp3)
where
menuvideo 1 is an identifier that is dynamically generated by the VXML interpreter and corresponds to the “literal” video in the script that displays the menu options; speech 1 is an identifier that is dynamically generated by the VXML interpreter and corresponds to the “literal” speech in the script that welcomes the caller and enumerates the menu options; animatedLogo.gif is the filename of a video source; and jingle1.mp3 is the filename of an audio source.
Of course, might be only 1 prompt-> list of 1 element.
Similarly, the block of consecutive <prompt>s in the formSales <form> block might correspond to ordered list:
L =(demo.3gp. video, demo.3gp.audio, animatedchart.gif, jingle2.mp3, trailer.3gp. video, trailer.3gp. audio)
where
demo.3gp.video denotes the video portion of file demo.3gp; demo.3gp.audio denotes the audio portion of file demo.3gp; animatedChart.gif is the filename of a video source; jingle2.mp3 is the filename of an audio source; trailer.3gp.video denotes the video portion of file trailer.3gp; and trailer.3gp.audio denotes the audio portion of file trailer.3gp.
At task 670 , interactive voice response (IVR) system 320 removes from list L any content stream identifier whose media type is not supported by the telecommunications terminal.
At task 680 , interactive voice response (IVR) system 320 spawns a thread for each media type Tin list L. For example, in the script of FIG. 4 IVR system 320 would spawn a thread for audio and a thread for video for both instantiations of list L. Each thread is passed list L and the <prompt> attribute values for each content stream in L. As will be appreciated by those skilled in the art, information can be passed to threads in a variety of ways, such as via a memory pointer, via an operating system inter-thread communication mechanism, and so forth. The operation of the threads is described in detail below and with respect to FIG. 7 .
At task 690 , interactive voice response (IVR) system 320 continues the execution of the IVR application instance, in well-known fashion. After task 690 , execution continues back at task 640 .
FIG. 7 depicts a flowchart of the salient tasks of a thread that is spawned at task 680 of FIG. 6 , in accordance with the illustrative embodiment of the present invention. It will be clear to those skilled in the art which tasks depicted in FIG. 7 can be performed simultaneously or in a different order than that depicted.
At task 710 , the thread initializes ordered list L′ to the content stream identifiers in list L that have the same media type T as the thread.
At task 720 , the thread sets variable S to the first content stream in list L′ and removes S from list L′.
At task 730 , the thread initiates playback of content stream S over C T , the channel that corresponds to media type T.
At task 740 , the thread checks whether the call has terminated. If so, the thread terminates, otherwise, execution continues at task 750 .
At task 750 , the thread checks whether channel C T is idle. If so, the thread continues its execution at task 780 , otherwise execution proceeds to task 760 .
At task 760 , the thread determines whether the <prompt> attribute values indicate that the current content stream in channel C T should continue playing (e.g., the current content stream has its persist attribute equal to true and content streams of other media types are still playing, etc.). If so, execution continues back at task 740 , otherwise execution proceeds to task 770 .
As will be appreciated by those skilled in the art, some embodiments of the present invention might employ other attributes in addition to, or instead of, the persist attribute to specify the manner in which content streams are played. For example, a Boolean concurrency attribute for a particular content stream S might indicate whether other content streams that have a media type different than S can be played simultaneously with S. As another example, a Boolean supplant attribute for a particular content stream S might indicate whether S can supplant a currently-playing content stream of the same media type, perhaps even when the current stream has persist equal to true.
As will be further appreciated by those skilled in the art, some embodiments of the present invention might employ attribute values that are dynamically-evaluated conditions (e.g., supplant=(currentStream.timeleft( )<10), etc.), or might employ attributes that have data types other than Boolean (e.g., minTimePlayed=4, etc.). Furthermore, some embodiments of the present invention might employ another scripting language instead of, or in addition to, VXML (e.g., Speech Application Language Tags [SALT], etc.), and it will be clear to those skilled in the art, after reading this specification, how to make and use such embodiments.
At task 770 , the thread stops the current content stream of channel C T , in well-known fashion.
At task 780 , the thread checks whether ordered list L′ is empty. If so, the thread terminates, otherwise, execution continues back at task 720 .
It is to be understood that the above-described embodiments are merely illustrative of the present invention and that many variations of the above-described embodiments can be devised by those skilled in the art without departing from the scope of the invention. For example, in this Specification, numerous specific details are provided in order to provide a thorough description and understanding of the illustrative embodiments of the present invention. Those skilled in the art will recognize, however, that the invention can be practiced without one or more of those details, or with other methods, materials, components, etc.
Furthermore, in some instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the illustrative embodiments. It is understood that the various embodiments shown in the Figures are illustrative, and are not necessarily drawn to scale. Reference throughout the specification to “one embodiment” or “an embodiment” or “some embodiments” means that a particular feature, structure, material, or characteristic described in connection with the embodiment(s) is included in at least one embodiment of the present invention, but not necessarily all embodiments. Consequently, the appearances of the phrase “in one embodiment” “in an embodiment” or “in some embodiments” in various places throughout the Specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments. It is therefore intended that such variations be included within the scope of the following claims and their equivalents. | A method and apparatus are disclosed that enable an interactive voice response (IVR) system to deliver content streams of various media types (e.g., video, audio, etc.) to telecommunications terminals. The illustrative embodiment provides extensions to the Voice extensible Markup Language (VXML) standard that enable an IVR system script to specify the playback order, timing, and coordination of multiple content streams (e.g., whether an audio stream and a video stream should be played back concurrently or serially; whether a particular content stream should finish before playback of another content stream commences; whether a content stream that is currently playing should be stopped and supplanted with another content stream, etc.). | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to sewing machine and more particularly to a sewing machine having a machine body and a wireless controller provided independently of the machine body.
2. Description of Related Art
Conventionally, a wireless foot controller for a sewing machine having a pedal is known. The foot controller transmits an operating speed command, corresponding to an amount the pedal is depressed, to a control device provided in the machine body that adjusts the operating speed of the machine.
In such a foot controller, a battery is generally used as the power source. Accordingly, when the battery is at the end of its useful life, resulting in a reduction in output voltage, the transmission of the operating speed command becomes unstable, and finally, no longer occurs. As a result, the machine malfunctions by running continually and cannot be stopped and the speed cannot be changed because the signal cannot be transmitted. As a needle reciprocates during operation of the sewing machine, any malfunction, such as the runaway machine is very dangerous to an operator and could result in an accident.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a sewing machine, having a wireless controller, that can prevent an improper operation of a machine body of the sewing machine due to an erratic or lost power source for the wireless controller.
It is another object of the present invention to provide a sewing machine having a wireless controller that can inform an operator that the power source for the wireless controller has been consumed.
According to the invention, to achieve the above objects, there is provided a sewing machine comprising a machine body having receiving means for receiving operational information; control means for controlling the machine body according to the operational information received by the receiving means; a wireless controller provided independently of the machine body and having transmitting means for transmitting the operational information to the machine body; a power source for supplying an electric power to the wireless controller; detecting means for detecting an output condition of the power source; determining means for determining whether the power source has been consumed based on the output condition of the power source detected by the detecting means; and informing means for informing an operator that the power source has been consumed when the determining means determines that the power source has been consumed.
In the sewing machine of the present invention, the receiving means of the sewing machine receives the operational information transmitted by the transmitting means of the wireless controller. The control means of the sewing machine controls the sewing machine according to the operational information received by the receiving means. The power source supplies electric power to the wireless controller. The detecting means detects the output condition of the power source. The determining means determines whether the power source has been consumed based on the output condition of the power source detected by the detecting means. The informing means informs an operator that the power source has been consumed when the determining means determines that such is the case.
According to the sewing machine of the present invention, the operator is informed by the informing means that the power source for the wireless controller has been consumed or nearly so. Therefore, improper operation of the sewing machine due to consumption of the power source for the wireless controller is prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the invention will be described in detail with reference to the following figures wherein:
FIG. 1 is a schematic illustration of the sewing machine according to a preferred embodiment of the invention;
FIG. 2 is a block diagram illustrating the electrical structure of the foot controller of the sewing machine;
FIG. 3 is a block diagram illustrating the electrical structure of a machine body of the sewing machine;
FIG. 4 is a diagram illustrating transmission data transmitted from the foot controller;
FIG. 5 is a flowchart of the power source monitoring process executed in the foot controller;
FIG. 6 a flowchart of the operating speed commanding process executed in the foot controller; and
FIG. 7 is a flowchart of the processing of the received data for execution by the sewing machine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment will be described in which the invention is employed in a sewing machine having a foot controller.
As shown in FIG. 1, the sewing machine according to the preferred embodiment has a sewing machine 2 and a foot controller 3. The foot controller 3 is accommodated in a controller box (not shown) formed independently of the sewing machine 2. The foot controller 3 includes a control unit 10, a transmitter unit 20, a pedal unit 30, and a power unit 40. The pedal unit 30 generates a signal for adjusting the operating speed of the sewing machine 2. The control unit 10 creates information for operating the sewing machine 2 according to the signal generated by the pedal unit 30. The transmitter unit 20 transmits the information created by the control unit 10 to a control device 5 in the sewing machine 2. The power unit 40 supplies electric power to the control unit 10, the transmitter unit 20, and the pedal unit 30.
The control device 5 is incorporated in the body of the sewing machine 2. The control device 5 includes a control unit 50, a receiver unit 60, a display unit 70, and a drive unit 80. The control unit 50 controls the operation of the sewing machine. The receiver unit 60 receives the information transmitted from the foot controller 3. The display unit 70 displays an operating mode of the sewing machine 2 and other messages. The drive unit 80 drives a machine motor 81.
The foot controller 3 will now be described in detail with reference to FIG. 2. The control unit 10 includes a CPU 10b, a ROM 10c, a RAM 10d, a timer 10e, and an input/output port 10f which are interconnected to one another by a bus 10a. These elements are all known in the art. The control unit 10 further includes a multiplexer 10g and an A/D converter 10h which are connected to the input/output port 10f. The multiplexer 10g selects one of plural input signals. The A/D converter 10h converts an analog voltage signal input from the multiplexer 10g to a digital signal. The input/output port 10f is connected through a data transmission bus 12 to the transmitter unit 20. The multiplexer 10g is connected to the pedal unit 30 and the power unit 40.
The ROM 10c stores a program for executing initializing processing such as clearing of a memory area or allocation of the input/output port 10f and programs for executing a power source monitoring process and an operating speed commanding process which will be further described. The ROM 10c also stores data representing a first reference voltage VR1, a second reference voltage VR2, and a voltage reduction rate K, to be described below. The RAM 10d includes a work area WA for data defined by the execution of the initializing process. The work area WA temporarily stores data representing a voltage signal VS and a difference value ΔV which will be described. The timer 10e can set a plurality of periods of time to be measured, in which the measurement of the periods can be individually started. The multiplexer 10g selects one of the input signals from the pedal unit 30 and the power unit 40, according to a select signal from the input/output port 10f, and then outputs the signal selected to the A/D converter 10h.
The transmitter unit 20 includes an encoder 20a, an FM modulator circuit 20b and a transmitting antenna 20c. The encoder 20a converts parallel data, including operating speed and status data input from the control unit 10 through the data transmission bus 12, into a serial bit pulse modulated in pulse width. The FM modulator circuit 20b modulates the frequency of a carrier wave by the serial bit pulse from the encoder 20a and transmits the frequency-modulated carrier wave from the transmitting antenna 20c. In the transmitter unit 20, the operating speed and status data, input from the input/output port 10f in the control unit 10 through the data transmission bus 12, constitute transmission data and this transmission data is transmitted to the control device 5 in the sewing machine 2. In the transmission data, as shown in FIG. 4, bit pulse having a short pulse width is represented as a bit 0 and the bit pulse having a long pulse width is represented as a bit 1. The operating speed data (OSD) has a 7-bit length, and the status data (SD) has a 9-bit length. The leftmost two bits of the status data are allocated for a battery data (BD) relating to replacement of the battery 40a provided in the power unit 40. A start mode signal (SMS) representing a start of the transmission data and an end mode signal (EMS) representing an end of the transmission data are represented by pulses having a width greater than that of the bit 1.
The pedal unit 30 includes a pedal 30a provided on an operation wall surface of the control box and a variable resistor 30b. The variable resistor 30b outputs a voltage signal VSP, according to an amount the pedal 30a is depressed, to the multiplexer 10g in the control unit 10.
The power unit 40 includes a stabilizer circuit 40b as well as the battery 40a. The stabilizer circuit 40b is supplied with electric power from the battery 40a and supplies a constant voltage Vcc to the control unit 10, the transmitter unit 20 and the pedal unit 30 irrespective of fluctuations with power consumption of each unit 10, 20 and 30. An output voltage of the battery 40a is generated as a voltage signal VBT through voltage dividing resistors R1 and R2 to the multiplexer 10g in the control unit 10. Because the voltage dividing resistors R1 and R2 have a large resistance, little current flows. Further, the stabilizer circuit 40b employs a known three-terminal regulator constructed by C-MOS which is operable by a very small power. Accordingly, the power unit 40 itself consumes very little electric power.
The control device 5 in the body of the sewing machine 2 will now be described with reference to FIG. 3. The control unit 50 includes a CPU 50b, a ROM 50c, a RAM 50d, an input/output port 50e and a timer 50f which are interconnected to one another by a bus 50a. The input/output port 50e is connected through a data transmission bus 52 to the receiver unit 60. The input/output port 50e is also connected to the display unit 70 and the drive unit 80.
The ROM 50c stores programs for processing received data, a machine motor drive control process and a machine operation temporary stop process which will be described. The RAM 50d temporarily stores an operation stop flag F.
The receiver unit 60 includes a demodulator circuit 60a, a decoder 60b, and an antenna 60c. The demodulator circuit 60a receives a carrier wave transmitted from the foot controller 3, through the antenna 60c, and then demodulates the carrier wave to output a serial bit pulse to the decoder 60b. The decoder 60b converts the serial bit pulse into parallel data, and outputs the parallel data through the data transmission bus 52, to the input/output port 50e in the control unit 50.
The display unit 70 includes a display 70a and a display control circuit 70b. The display control circuit 70b controls the display 70a to display a machine operation mode and various messages such as a message of preparation for battery replacement or a message of urgent battery replacement, according to a display command signal from the control unit 50.
The drive unit 80 energizes the machine motor 81 according to a pulse signal input from the control unit 50.
The power source monitoring process executed in the control unit 10 of the foot controller 3 will now be described with reference to the flowchart of FIG. 5. The power source monitoring process is repeatedly executed by the CPU 10b at a given cycle (such as 20 or 30 minutes, for example) according to a measuring time set by the timer 10e. When the power source monitoring processing is started, the voltage signal VBT from the power unit 40 is read in step S10. In step S20, it is determined whether the level of the voltage signal VBT is equal to or lower than the first reference voltage VR1 stored in the ROM 10c (VBT≦VR1 ?). The first reference voltage VR1 is established at a voltage level that when the power consumption is zero, an output voltage of the battery 40a can be restored to a rated voltage range. In step S20, if it is determined that the level of the voltage signal VBT is higher than the first reference voltage VR1, the program jumps to step S80. In step S20, if it is determined that the level of the voltage signal VBT is equal to or lower than the first reference voltage VR1, the program proceeds to step S30.
In step S30, it is determined whether the level of the voltage signal VBT is equal to or lower than the second reference voltage VR2 stored in the ROM 10c (VBT≦VR2 ?). The second reference voltage VR2 is set at a voltage level lower than that of the first reference voltage VR1, and this voltage level is a minimum rated voltage level ensuring the operation of the foot controller 3. Accordingly, in step S30, it is determined whether a dead state of the battery 40a is nearing. In step S30, if the answer is YES, that is, if it is determined that the dead state of the battery 40a is nearing, the program jumps to step S90. In step S30, if the answer is NO, that is, if it is determined that some time remains until the battery 40a approaches the dead state, the program proceeds to step S40. In step S40, it is determined whether the level of the voltage signal VBT is lower than the level of the previous voltage signal VS stored in the work area WA of the RAM 10d in the previous processing (VBT<VS ?). In step S40, if it is determined that the level of the voltage signal VBT is equal to or higher than the level of the previous voltage signal VS, the program jumps to step S80. In step S40, if it is determined that the level of the voltage signal VBT is lower than the level of the previous voltage signal VS, the program proceeds to step S50.
In step S50, a level difference between the previous voltage signal VS and the present voltage signal VBT is calculated as the difference value ΔV (ΔV=VS-VBT) and the program then proceeds to step S60. The difference value ΔV corresponds to a voltage reduction rate. In step S60, it is determined whether the difference value ΔV is equal to or larger than the predetermined voltage reduction rate K stored in the ROM 10c. On this basis, it is determined whether the rate of consumption of the battery 40a is large. In step S60, if the answer is NO, that is, if it is determined that the rate of consumption of the battery 40a is small, the program goes to step S80. In step S60, if the answer is YES, that is, if it is determined that the degree of consumption of the battery 40a is large, the program proceeds to step S70. In step S70, battery replacement preparation data indicating that a time for replacing the battery 40a will come soon is set in the battery data that constitutes a part of the status data of the transmission data and that cycle of the power source monitoring process ends.
In the case where the program jumps from steps S20, S40 or S60 to step S80, the present voltage signal VBT is stored as the voltage signal data VS in a given portion of the work area WA of the RAM 10d and that cycle of the power source monitoring process ends.
In the case where it is determined in step S30 that the level of the voltage signal VBT is equal to or lower than the second reference voltage VR2, that is, it is determined that the dead state of the battery 40a is nearing, and the program jumps to step S90, an urgent replacement data indicating that urgent replacement of the battery 40a is required is set in the battery data and that cycle of the power source monitoring process ends.
The operating speed commanding process executed in the control unit 10 of the foot controller 3 will now be described with reference to the flowchart shown in FIG. 6. The operating speed commanding process is repeatedly executed by the CPU 10b at a given cycle according to a measuring time set by the timer 10e. However, the execution cycle of the operating speed commanding process is sufficiently shorter (a period of milliseconds, for example) than the execution cycle of the aforementioned power source monitoring process. When the execution timing of the operating speed commanding process coincides with the execution timing of the power source monitoring process, the operating speed commanding process is executed first followed by execution of the power source monitoring process.
When the operating speed commanding process is started, the voltage signal VSP from the pedal unit 30 is read in step S100. The voltage signal VSP is of a level corresponding to the amount of depression of the pedal 30a. Next, an operating speed data corresponding to the level of the voltage signal VSP is set in step S110. Finally, in step S120, a transmission data is formed from the operating speed data set in step S110 and added to the status data which includes the battery data set by the aforementioned power source monitoring process. Then, the transmission data is transferred to the transmitter unit 20 and that cycle of the operating speed commanding process ends.
During execution of the power source monitoring process and the operating speed commanding process by the CPU 10b, when the degree of consumption of the battery 40a is large, the transmission data is formed from the operating speed data and the status data including the battery replacement preparation data, while when the dead state of the battery 40a is nearing, the transmission data is formed from the operating speed data and the status data including the urgent replacement data. The transmission data transferred to the transmitter unit 20 is transmitted from the transmitter unit 20 to the control device 5 in the body of the sewing machine 2.
When the receiver unit 60 in the control device 5 of the sewing machine 2 receives the transmission data from the foot controller 3, the control unit 50 processes the received data. Processing of the received data will be described with reference to the flowchart shown in FIG. 7. When processing of the received data is started by the CPU 50b of the control unit 50, it is determined in step S200 whether the operation stop flag F, stored in the RAM 50d, is at a set state of 1. If the answer in step S200 is YES, the program goes to step S280. If the answer in step S200 is NO, the program proceeds to step S210. In step S210, it is determined whether the battery data received is the battery replacement preparation data. If the answer in step S210 is NO, the program goes to step S250. If the answer in step S210 is YES, the program proceeds to step S220.
In step S220, a display command of "prepare for battery replacement" is output to the display unit 70. As a result, the display 70a driven by the display control circuit 70b, displays a message of "prepare for battery replacement". In step S230, the operating speed of the sewing machine 2 is set according to the operating speed data received. In step S240, a machine motor drive control process is executed and processing of the received data ends. As a result, the machine motor 81 is driven by the drive unit 80 at the operating speed set above until the next transmission.
In the case that the answer in step S210 is NO, and the program goes to step S250, it is determined in step S250 whether the battery data received is the urgent replacement data. If the answer in step S250 is NO, that is, if the battery 40a is normal such that no replacement of the battery 40a is required, the above described processings of step S230 and step S240 are executed and processing of the received data ends. If the answer in step S250 is YES, the program proceeds to step S260. In step S260, the operation stop flag F is set to 1 and is stored into the RAM 50d. Then, in step S270, a display command of "urgently replace battery" is output to the display unit 70, and in step S275, a measuring time (for example, five seconds) is set by the timer 50f. Thus, processing of the received data ends. As a result, the display 70a is driven by the display control circuit 70b to display the message "urgently replace battery" for the set measuring time.
In the case where it is determined in step S200 that the operation stop flag F is set at 1, and the program goes to step S280, the operation stop flag F is reset. Then, in step S290, a display command of "temporary stop of machine operation" is output to the display unit 70. As a result, the display 70a is driven by the display control circuit 70b to display the message "temporary stop of machine operation". Then, in step S300, a machine operation temporary stop process, for safely temporarily stopping the operation of the sewing machine 2 is executed and the processing of received data process ends. As a result, the machine motor 81 is temporarily stopped by the drive unit 80. Thus, when the battery 40a is not replaced, in spite of the display of the message of "urgently replace battery" in step S270, but sewing machine operation is continued, the operation of the sewing machine 2 is temporarily stopped in step S300, at the next operating speed commanding process cycle after the expiration of the measuring time, so as to prevent a malfunction of the sewing machine 2 and ensure the safety of an operator.
As described above, in this preferred embodiment, when the voltage signal VBT of the battery 40a becomes equal to or lower than the first reference voltage VR1, and the voltage reduction rate is equal to or larger than the predetermined voltage reduction rate K, the message of "prepare for battery replacement" is displayed. Further, when the voltage signal VBT becomes equal to or lower than the second reference voltage VR2, the message of "urgently replace battery" is displayed. Therefore, the operator is exactly informed of the degree of urgency for replacement of the battery 40a.
Further, the message of "prepare for battery replacement" or "urgently replace battery" informing the operator that the battery 40a in the foot controller 3 has been nearly consumed or consumed is displayed on the display 70a of the sewing machine 2 which is easily seen by the operator rather than on the foot controller 3 which is located at the operator's foot. Therefore, the operator is surely informed of the time for replacement of the battery 40a.
Further, when the battery 40a is not replaced in spite of displaying of the message of "urgently replace battery", operation of the sewing machine 2 is automatically stopped temporarily. Therefore, improper or unsafe operation of the sewing machine 2 is prevented.
Further, as both the first reference voltage VR1 and the second reference voltage VR2 are predetermined, when the voltage signal VBT of the battery 40a becomes equal to or lower than the first reference voltage VR1, the rate of voltage reduction, that is, the output reduction rate of the battery 40a, is compared with the predetermined voltage reduction rate K. Accordingly, a time of battery replacement can be properly determined and the operator informed according to a fluctuation in an output reduction characteristic of the battery 40a due to a temperature change or a change in kind of battery 40a.
For instance, when the temperature is 0° C., or the battery 40a is a lithium battery or an alkaline-manganese is normally small. Accordingly, even when the voltage signal VBT of the battery 40a becomes equal to or lower than the first reference voltage VR1, a certain time still remains until the battery must be replaced. In contrast, when the temperature is 50° C., or the battery 40a is a silver oxide battery or a mercury battery, the rate of voltage reduction of the battery 40a is rapid. Accordingly, when the voltage signal VBT of the battery 40a becomes equal to or lower than the first reference voltage VR1, little time remains until the battery must be replaced. In these circumstances, by determining whether the battery 40a has been consumed according to the rate of voltage reduction of the battery 40a, i.e., the output reduction characteristic of the battery 40a, when the voltage signal VBT of the battery 40a becomes equal to or lower than the first reference voltage VR1, a time for displaying of the message of "prepare for battery replacement" can be properly decided.
The invention is not limited to the above-mentioned preferred embodiment, but various modifications may be made without departing from the scope of the present invention.
For instance, in the case where the power consumption of the foot controller 3 is temporarily increased to cause a reduction in the voltage signal VBT to the first reference voltage VR1 or less, a current detecting circuit may be provided as shown in FIG. 2 by the dashed line. In this case, when the consumed current detected by the current detecting circuit is equal to or more than a predetermined level, the execution of the power source monitoring process is deferred. After the consumed current becomes less than the predetermined level, and a time necessary for restoring the electromotive force and the output voltage of the battery 40a has elapsed, the execution of the power source monitoring process is restarted. With this structure, the time of battery replacement can be determined more accurately.
Further, a rechargeable battery may be used as well as a disposable battery as the battery 40a. | In a sewing machine having a remote battery powered foot pedal control, that communicates with the sewing machine proper via a wireless signal, a monitoring system that periodically monitors the status of the battery and provides that information from the foot pedal control, along with speed instructions, to the sewing machine proper. A display on the sewing machine informs the operator when battery change time is approaching and when replacement is urgently needed. If the battery is not replaced when replacement is urgent, the sewing machine ceases operations. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a tool for use in the installation of fiberglass insulation or rock wool in residential and commercial buildings, and more specifically a tool designed to insert such insulation in the roof rafters of previously constructed homes.
2. Description of the Prior Art
Fiberglass insulation and rock wool are the two most common types of insulation used on previously constructed homes. When they are installed the workmen must be constantly cutting and sizing the sheets of insulation. The insulation is usually supplied in the form of rolls. The installer will usually cut with a knife manageable lengths of the material. As the material is installed in the rafters the installer will usual note a witness mark for the previously installed section. This is because the next sheet of insulation is pushed inward to a length less the predetermined amount the units of insulation have been cut. This is to accommodate the slope and therefore shorter sections are required. At present there is no tool available to provide the installer an easy yet effective means for judging this distance and having a tool that will of itself accommodate these differences.
The prior art does disclose some patents that have anticipated the problems of installing these types of insulation. One such patent was issued to Schultz on Apr. 12, 1994. This was U.S. Pat. No. 5,301,378 which taught of a tool for installing fiberglass insulation. Although quite different in construction from the present invention, it was the only patent that addressed the subject.
Other patents such as U.S. Pat. No. 6,048,010, issued to Stocker on Apr. 11, 2000, teach of tools for manipulation of material sections to overhead heights.
None of the above inventions and Patents, taken either singly or in combination, are given to describe the instant invention as claimed.
SUMMARY OF THE INVENTION
Accordingly, the above problems and difficulties are obviated by the present invention which provides for an installation tool designed to be adaptable for differences in rafter heights or lengths. The present invention is designed to insert sheets of insulation, in previously constructed homes and buildings, between the roof rafters of difficult to reach places such as dormers. The insulation is cut into manageable size sheets for insertion into the roof and eaves of the building. The present invention is opened by rotating a handle thereby operating a cam slotted flange. A sheet of insulation is placed between a pair of gripping plates and the handle is rotated in a counterclockwise direction to securely grasp the sheet. The user need only to reverse the handle direction to release the sheet. As the sheets of insulation are installed, beginning at the furthermost point, a witness mark is noted on the handle of the tool. By precutting the insulation sheets the installer can coordinate the distance the sheets must be pushed into position, noting with a witness mark this distance on the handle. The handle of the tool is adjustable lengthwise and as previously mentioned can be marked in increments corresponding to the precut installation sheets. To insure that there be no appreciable gaps, an adjustable rod (not part of inventive concept) is applied to the top surface of each bay as it is filled, thereby allowing for an air space for venting and prevention of moisture traps.
The present invention can be dismantled slightly so that the handle portion can be removed from the cam operated gripping plates. This feature is especially useful wherein a tamper add-on can be affixed to the distal end of the handle section to aid in aligning the insulation material as they are installed.
Accordingly, it is a principal object of the invention to provide an installation tool that will grasp the insulation material that is to be pushed into position, while also allowing the installer to be able to know how far he must push by visually noting the witness marks on the handle.
It is another object of the invention to provide an installation tool that is very inexpensive since insulating one's home would be done so rarely that the tool would almost have to be considered a one application tool, however it must be built rugged enough for use by the professional installer of insulation.
It is an object of the invention to provide a tool that not only would be used to install the insulation material but which is adjustable in length.
It is another object of the invention to provide a tampering tool that could also be used to “tap” the insulation sections into position.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective elevation view of the present invention in an open position.
FIG. 2 is an elevation view of the post section removed from the sleeve section.
FIG. 3 is a perspective view of the handle portion affixed with a tampering block.
FIG. 4 is a top view of the grasping portion in an open position.
FIG. 5 is a top view of the grasping portion in a closed position.
FIG. 6 is a bottom view of the grasping portion in an open position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, the present invention is shown as it might appear when opened and ready to grasp a sheet of fiberglass insulation. The installation tool of the present invention 10 comprises a longitudinal axis and an elongated handle portion 11 integrally connected to a grasping portion 12 by means of a cam flange disk 13 .
As shown in FIG. 1, the handle portion 11 is comprised of a hollow sleeve section 14 having an outer surface fluted for easy handling. Sleeve section 14 is coaxial with the longitudinal axis of the tool 10 and preferably of a tubular shape and made of appropriate material such as plastic or lightweight metal. Sleeve section 14 having a plurality of equidistantly spaced openings 15 in the shell of the sleeve 14 . The handle portion 11 also comprising an elongated post member 16 which is interposed coaxial within the sleeve section 14 , such that it may slide within the axis of the sleeve 14 to thereby extend or shorten the length of the handle portion 11 . The post 16 having a proximal end 17 and a distal end 18 as shown in FIG. 2 . The post 16 further having at least one spring loaded button 19 which when properly aligned with one of the openings 15 of the sleeve section 14 will retain the post 16 at that position in the sleeve 14 . The distal end 18 of the post 16 having a rounded tip 20 which is friction fitted to a circular hole 28 in the cam flange disk 13 of the grasping portion 12 . This tip 20 may also be friction fitted to a tampering block 21 as illustrated in FIG. 3 . This creates a tool that can be used to “tap down” the fiberglass sheets to insure a smooth and tight fit.
The grasping portion 12 as illustrated in FIGS. 1, 4 - 6 , is comprised of a pair of angle iron shaped gripping plates, a first gripping plate 22 a and a second gripping plate 22 b , which are maintained in a parallel relationship to each other by the movement of the cam flange disk 13 . Two arc shaped slots 26 are defined in the cam flange disk 13 . Each of the gripping plates 22 a and 22 b , having lip sections 24 formed in their upper areas, are attached to the cam flange disk 13 by a connecting pin 30 . A pair of stabilizing strips, a first stabilizing strip 25 a and a second stabilizing strip 25 b , each having opposing ends: one end of the first stabilizing strip 25 a being rotationally attached to the first gripping plate 22 a by one of the connecting pins 30 , while one end of the second stabilizing strip 25 b being rotationally attached to the second gripping plate 22 b by the other connecting pin 30 ; the other end of the first stabilizing strip 25 a being in a sliding relationship with the opposing second gripping plate 22 b by a lug nut 23 slidingly transposing within an aperture 29 located in the lip section 24 of the second gripping plate 22 b , and the other end of the second stabilizing strip 25 b in a sliding relationship with the opposing first gripping plate 22 a by a lug nut 23 slidingly transposing within an aperture 29 located in the lip section 24 of the first gripping plate 22 a.
Upon the handle portion 11 being rotated, the gripping plates 22 a and 22 b are either opened or closed. When rotated in a counterclockwise direction, plates 22 a and 22 b are opened to define a receiving space 27 . When rotated in a clockwise rotation, they are therein closed. This is accomplished by the having the arc shaped slots 26 a and 26 b of the cam flange section 13 each rotate about a connecting pin 30 , whereby the gripping plates 22 a and 22 b are either forced open or closed. Providing the tool 10 a degree of structure and strength while being opened or closed is the function of the stabilizing strips 25 a and 25 b . One end of the first stabilizing strip 25 a being rotationally fastened at the center area of the lip section 24 of the plate 22 a by a connecting pin 30 and at the other end being fastened in a sliding relationship with the outer edge of the lip section 24 of the plate 22 b by means of a lug nut 23 , which is allowed to slide freely within the aperture 29 . Conversely, the other stabilizing strip 25 b , one end being rotationally fastened at the center area of the lip section 24 of plate 22 b by a connecting pin 30 and the other end being fastened at the outer edge of the lip section 24 of plate 22 a by means of a lug nut 23 which is allowed to slide freely within the aperture 29 . Thus as the plates 22 a and 22 b are opened or closed, the stabilizing strips 25 a and 25 b each rotate at one end about one of the corresponding connecting pins 30 , while the other ends slide within the corresponding apertures 29 a and 29 b . This prevents any “buckling” action between the plates 22 a and 22 b . Both the connecting pins 30 and the lug nuts 23 , have a nut and bolt type of structure. The bottom sections are juxtaposed against the surface of one of the strips 25 a or 25 b and resemble the head of a bolt while the upper sections have a nut type structure with an outer diameter larger than either of their respective cam flange slots 26 a or 26 b or the apertures 29 . Thereby, as they protrude through and are urged in a transverse motion, they are able to maintain the connections therein. Gripping plates 22 a and 22 b , stabilizing strips 25 a and 25 b , and cam flange section 13 are designed to be manufactured from a lightweight metal or plastic.
A very useful idea that can be employed when using the present invention 10 is to employ witness marks on the handle portion to indicate how far the insulation material needs to be inserted. Whether the application be in a roof, dormer or eave section of the house or building, the fiberglass material will need to be cut into predetermined sizes and then placed into their proper position.
The insulation tool 10 will need to be inexpensively manufactured, yet needs to be rugged enough and strong enough to handle the task. The best materials for construction will be very lightweight plastic for the handle portion 11 and lightweight metal for the grasping portion 12 .
Although only one use and embodiment of the present invention has been described in detail hereinabove, all improvements and modifications to this invention within the scope or equivalents of the claims are covered by this invention. | A tool for installing fiberglass insulation. The tool having a handle with a telescopically movable post for extending its length. The tool having a grasping portion for holding the insulation. The grasping potion comprising of a pair of gripping plates, each with a stabilizing strip attached thereto. A cam flange section integral with the tops of the plates and having a pair of arc shaped slots for sliding engagement with the plates. Rotation of the handle causing the plates to either open or close. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a hermetic compressor, and more particularly, to a discharge valve of a hermetic compressor which is installed in a cylinder head and discharges a compressed refrigerant.
2. Description of the Related Art
Generally, a hermetic compressor is employed in equipment using a refrigerant, such as an air conditioner, and a refrigerator, for compressing the refrigerant.
As shown in FIG. 1, a general conventional hermetic compressor comprises a stator 1 , a rotor 2 rotating inside the stator 1 , a crank shaft 3 revolving with the rotor 2 , a piston 5 connected to the crank shaft 3 . A connecting rod 4 , reciprocates linearly with the revolution of the crankshaft 3 . A cylinder 6 forms a compressive chamber 6 B, together with the piston 5 , and a valve assembly 7 assembled into a cylinder head 6 A for controlling the discharge and a suction of the refrigerant.
The valve assembly 7 consists of an intake valve, which opens during an intake stroke when the piston 5 moves to the bottom dead center and closes during a discharge stroke when the piston moves to the top dead center, and a discharge valve, which opens during the discharge stroke and closes during the intake stroke.
Referring to FIG. 2, the discharge valve 10 includes a valve plate 11 , a reed valve 13 , a stopper 14 , and a keeper 16 .
The valve plate 11 has an intake hole 8 for refrigerant intake into the chamber 6 B (FIG. 1) and a discharge hole 12 for discharging refrigerant. The discharging hole 12 is formed in a recess 11 A of the discharge plate 11 .
Within the recess 11 A are consecutively piled on and installed in sequences the reed valve 13 for opening/closing the discharge hole 12 , the stopper 14 for controlling the degree of opening of the reed valve 13 , and the keeper 16 for preventing the reed valve 13 and the stopper 14 from separation from the discharge plate 11 .
The operation of the conventional hermetic compressor comprising the same structure as that described above is explained hereafter.
When the rotor 2 rotates by the mutual operation of the rotor 2 and the stator 1 , the crank shaft 3 assembled together with the rotor 2 revolves. When the crank shaft 3 rotates, the refrigerant is drawn into and discharged as the piston 5 reciprocates rectilinearly inside the cylinder 6 by the reciprocal action of the connecting rod 4 eccentrically assembled at the end of the crank shaft 3 .
For the start of a discharge stroke, the piston 5 moves to the bottom dead center and inside the compressive chamber 6 B forms a vacuum. Accordingly, the intake valve (not shown) of the intake hole 8 opens by the refrigerant pressure which displaces the valve toward the vacuum and the refrigerant flows into the compressive chamber 6 B. At this point, the reed valve 13 (FIG. 2) keeps the discharge hole 12 closed. With the piston 5 at the bottom dead center, the piston 5 moves back to the top dead center and thereby the discharge stroke compresses the refrigerant and discharges it through the discharge hole 12 and into a discharge tube 9 (FIG. 1 ). During the discharge stroke, the intake valve closes off the intake hole 8 by means of the pressure of the compressed refrigerant whereby the compressed refrigerant is discharged through the discharge hole 12 by the same pressure pushing up the reed valve 13 and the stopper 14 .
In addition, when the piston 5 reaches the top dead center, it begins its movement back again to the bottom dead center, the reed valve, which was moved up and open, falls down and closes the discharge hole 12 and continuous suction and discharge of the refrigerant proceed as the intake valve of the intake hole 8 opens.
Accordingly, the hermetic compressor continues the refrigerating cycle of refrigerant intake, compressing the refrigerant and discharging the compressed refrigerant in accordance with the above described process.
However, in the above discharge valve 10 , in order for the refrigerant to be discharged during the discharge stroke the discharge hole 12 should be opened by the actions of lifting the reed valve 13 and the stopper 14 . In other words, since the force produced by the discharge pressure of the refrigerant should be higher than the total closing force due to the elasticity of the reed valve 13 and the stopper 14 in order for the discharge hole 12 to remain open. Opening of discharge hole 12 allows the refrigerant to discharge, mere and a higher refrigerant pressure than the pressure required for operation of the pressurization of the refrigerant will be required in compressive chamber 6 B. When the cylinder 6 is over pressurized, more power is needed to rotate the rotor 2 , thereby resulting in the operation of the hermetic compressor in a less efficient state.
Additionally, it is also problematic in that the compressor makes loud noises due to the beating or impulse sounds made by the reed valve 13 hitting the top of the discharge hole 12 due to the elastic closing force of the reed valve 13 and the stopper 14 combination, and in the action of the piston 5 occurring at the time of the intake stroke.
SUMMARY OF THE INVENTION
The present invention has been made to overcome the above-mentioned problems of the prior art, and accordingly, it is an object of the present invention to provide a discharge valve for a hermetic compressor that is quiet and effective as a result of the cylinder not being over-pressurized by compressing and discharging the refrigerant against the weight of the valve itself during the discharge stroke.
Another object of the present invention is to provide a discharge apparatus of a hermetic compressor that is simple in shape, simple to process and assemble by being comprised of a small number of structural elements.
In order to achieve the above objects, according to the present invention a discharge valve of a hermetic compressor is installed in a cylinder head which opens and closes according to the reciprocal movement of a piston moving within the cylinder head, for discharging compressed refrigerant. The discharge valve of the hermetic compressor includes a valve plate disposed on the cylinder head of the hermetic compressor providing intake and discharge of refrigerant according to reciprocal movement of the piston. The discharge valve has a discharge hole formed therein through which refrigerant is discharged, a disc valve disposed above the discharge hole of the valve plate, being raised or lowered by the reciprocal movement of the piston, and a stopper disposed adjacent the disc valve and separated from the discharge hole, for guiding the raising and lowering of the disc valve and also for limiting the height to which the disc valve may be raised to a predetermined range. Alternatively, a hermetic compressor having a cylinder head and a piston for providing sequentially intake and discharge of a refrigerant during an intake/discharge cycle, adjacent to a discharge valve, the discharge valve may comprise a valve plate disposed on the cylinder head including a discharge hole formed therein for discharge of the refrigerant, a disc valve disposed adjacent the discharge hole of the valve plate, so as to cover the discharge hole during a portion of the intake/discharge cycle depending on the pressure developed within the cylinder head by the piston, and a stopper, adjacent to the disc valve and spaced from the discharge hole, including guides for guiding the orientation of the disc valve and a stopper portion for limiting to a predetermined range the reciprocal motion of the disc valve between the disc hole and the stopper portion.
Preferably, the stopper is connected to the valve plate with a space therebetween by a plurality of guiding pins that are standing upright around the discharge hole of the valve plate, to thereby guide the disc valve by point-contact between the disc valve and the guiding pins.
In another embodiment, the stopper is connected to the valve plate with a space therebetween due to supporting members extending downward from two ends of the stopper, for guiding the disc valve by line-contact of the supporting member and an edge of the disc valve. The stopper is connected to the valve plate with a space therebetween due to a supporting member extending downward from one end of the stopper, and has a plurality of guiding pins protruding from the other end of the stopper toward the valve plate for guiding the disc valve.
The stopper preferably comprises at least three guiding pins, one end of each guiding pin being connected to a circumference of the discharge hole of the valve plate in a vertical manner, while on the other end of each guiding pin is formed an extended end for limiting the height to which the disc valve may be raised.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforementioned objects and characteristics of the present invention will be made more apparent by describing a preferred embodiment of the present invention in greater detail with reference to the accompanying drawings, in which:
FIG. 1 is a sectional side view showing a general conventional hermetic compressor;
FIG. 2 is an exploded perspective of a conventional discharge valve;
FIG. 3 is an exploded perspective showing the first embodiment of a discharge valve of the hermetic compressor in accordance with the present invention;
FIG. 4A is a sectional view showing the disc valve of FIG. 3 being guided by three guiding pins;
FIG. 4B is a sectional view showing the disc valve of FIG. 3 being guided by two guiding pins;
FIG. 5A is a cross-sectional view showing the discharge valve of FIG. 3 in a closed position;
FIG. 5B is a cross-sectional view showing the discharge valve of FIG. 3 in an open position;
FIG. 6 is a cross-sectional view showing a second embodiment of the hermetic compressor according to the present invention;
FIG. 7 is a cross-sectional view showing a third embodiment of the hermetic compressor according to the present invention;
FIG. 8 is a perspective view showing a fourth embodiment of the hermetic compressor according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, a preferred embodiment of the present invention will be described in greater detail with reference to the accompanying drawings.
Referring to FIGS. 3 to 5 B, the discharge valve 100 of a hermetic compressor according to the first embodiment of the present invention includes a valve plate 101 , a disc valve 103 , a stopper 105 and a number of guiding pins 107 .
The valve plate is disposed on the cylinder head and has a discharge hole 102 for discharging a refrigerant and an intake hole 8 (FIG. 2) for refrigerant intake into the compression chamber. It is preferable that a seating portion 102 a is formed at the top of the discharge hole 102 , as shown, for the disc valve 103 to effectively close the discharge hole 102 .
Being located at the top of the discharge hole 102 , the disc valve 103 , which is used for closing the discharge hole 102 , helps the refrigerant to be compressed by closing the discharge hole with its own weight at the time of the discharge stroke and helps the refrigerant to be discharged as the disc valve 103 is raised by the pressure when the compressive force inside the cylinder exceeds the disc valve weight. Preferably the disc valve 103 is shaped and dimensioned to be bigger than the diameter of the discharge hole 102 so that it can close the discharge hole 102 and may take the shape of a disc, although it is preferred that the shape corresponds to the shape of the discharge hole 102 .
The stopper 105 is disposed on the top of the discharge valve 103 of the discharge hole 102 and restricts the height the disc valve 103 can be raised when the disc valve 103 is raised by the pressure of the refrigerant during the discharge stroke. Additionally, the middle of the stopper has a through hole 105 A communicating with the discharge hole 102 for smooth flow of the discharged refrigerant.
Each guiding pin 107 , having a cylindrical shape, fastens the stopper to the valve plate 105 so that the stopper can be attached at a predetermined distance from the valve plate 105 . The guiding pins 107 guide the disc valve 103 during the raising and lowering movements. The method of fastening the guiding pins 107 to the valve plate 101 can take various forms, including welding, but riveting 108 , as shown in FIGS. 5A and 5B, is preferable. In addition, for the guiding pin 107 to guide the raising and lowering movement stably and by engaging the disc 103 in point-contact, at least three guiding pins 107 are needed, as shown in FIG. 4 A. Undoubtedly, in the case of the alternative shape of the disc valve 103 ′ being as that shown in FIG. 4B, two guiding pins 107 only can stably guide the raising and lowering movement of the disc valve 103 ′.
The movement of the discharge valve in the first embodiment having the above described structure is described below.
Referring now to FIGS. 5A and 5B, when the piston moves to the bottom dead center during the intake stroke, the discharge valve is opened by the force of the fluid pressure acting on the discharge valve, not met by a counterforce because of the vacuum formed in the cylinder, and the refrigerant is drawn into the cylinder. At the same time, the disc valve 103 drops down by the force of the pressure of the fluid acting against disc valve 103 , causing it to move toward the vacuum and as a result of the weight of the disc valve 103 being attracted downwardly by gravity to close the discharge hole 102 , as shown in FIG. 5 A.
When the piston reaches the bottom dead center, it starts to compress the refrigerant while moving back to the top dead center. If the compressive pressure force developed by the piston on the disc valve 103 exceeds the weight of the disc valve 103 , the disc valve 103 will lift along the guiding pins 107 . As the disc valve 103 is lifted, its movement is stopped by the stopper 105 , as shown in FIG. 5B, and the compressed refrigerant being discharged through the discharge hole 102 is discharged through the space between the disc valve 103 and the valve plate 101 and finally out through the discharge tube 9 (FIG. 1 ).
During the discharge stroke, since the piston moves back to the bottom dead center and starts the intake stroke when it reaches the top dead center, intake and discharge of the refrigerant continue.
As the disc valve 103 is guided by the three guiding pins and engages them in point-contact during the discharge and intake stroke, it can stably open and close the discharge hole 102 .
The discharge valve 110 of the hermetic compressor according to a second embodiment of the present invention, shown in FIG. 6, is essentially identical to the hermetic compressor 100 , according to the first embodiment, except for having supporting members connected to the lower part of the stopper, instead of a connection provided by the guiding pins 107 . The supporting members help the stopper keep its predetermined distance and also to guide the disc valve 103 . In FIG. 6, the supporting members 112 are fastened to the valve plate 101 by the rivets 113 , but the method for fastening the supporting members 112 can take various forms, including welding. Cantilevered sections of the supporting members 112 form a stopper 111 that define a through hole 111 a provided at the stopper.
The movement of the discharge valve 110 according to the second embodiment is identical to that of the first embodiment except that the disc valve 103 is guided by line-contact with the inner surface of the supporting members 112 and the remaining operation steps therefore will not be described in detail. It should be noted that the cross-section view shown in FIG. 6 is taken through two oppositely disposed supporting members 112 , separated by fluid communication operatures (not shown), that support the stopper 111 in the form of a collar or annular ring.
Additionally, the discharge valve according to a third embodiment of the present invention is shown in FIG. 7 .
The discharge valve 120 according to the third embodiment is comprised of a valve plate 101 having a discharge hole 102 , a disc valve 103 opening and closing the discharge hole 102 according to the reciprocating movement of a piston, and a canti-levered stopper 121 restricting the height to which the disc valve 103 may be raised.
One end of the stopper 121 is fastened at a predetermined distance from the valve plate 101 by the supporting members 122 which extend toward the valve plate 101 by the cantilevered section. The fastening means for the supporting members 112 can include welding, as well as riveting 124 , which is shown in FIG. 7 .
In addition, the other end of the stopper has a number of guiding pins 123 that can guide the disc valve 103 . The guiding pins 123 protrude toward the valve plate 101 and the inner space of the circle formed by the guiding pins 123 defines a through hole 121 a.
The detailed description of the third embodiment having the above structure will be omitted as it is identical to the first embodiment except that the guiding pins 123 only function for guiding the disc valve 103 and the supporting members 122 of the stopper 121 limit the height to which the disc valve 103 may be raised.
Referring to FIG. 8, the discharge valve 130 hermetic compressor according to a fourth embodiment of the present invention has an identical structure to that of the first embodiment 100 except that the stopper is provided by the guiding pins 131 having extended end portions 131 a.
In the fourth embodiment 130 , the height to which the disc valve 103 may be raised is determined by the height of the extended end portion of the guiding pins 131 measured from the surface of the valve plate 101 , and the raising and lowering movements of the disc valve 103 are guided by the contact with guiding pins. Two guiding pins 131 may be sufficient but three are preferable.
According to the discharge valve of the hermetic compressor according to the present invention, as described above, the weight of the disc valve 103 only is applied in opening and closing the discharge hole 102 and the piston will not be over pressurized at the time of discharge since the elastic closing force of the reed valve 13 and the stopper 14 combination, as in the conventional compressor, are not utilized in the present invention.
In addition, at the time of the intake stroke when the disc valve 103 closes the discharge hole 102 , the noise is reduced as the beating sounds are reduced because the top of the discharge hole 102 is beaten only by the intake force and the weight of the disc valve 103 .
Also, the ease of manufacture and assembly and reliability of the products increase in comparison to the conventional discharge valve as the discharge valve simply comprises the disc valve 103 and the stopper 105 .
As described above, according to the discharge valve of the hermetic compressor of the present invention, the efficiency of the hermetic compressor can be improved as the disc valve 103 opens and closes the discharge valve by its own weight and the piston will not be over pressurized at the time of the discharge.
Additionally, the noises made by the beating sounds from the discharge hole are reduced as the discharge hole is opened and closed by the weight of the disc valve 103 and the force of intake motion only.
In addition, the ease of manufacture and assembly and reliability of the products increase as the shape of the discharge valve is simplified to a disc shape and a number of structural elements are eliminated.
Although the preferred embodiments of the present invention have been described, it will be understood by those skilled in the art that the present invention should not be limited to the described preferred embodiments. Various changes and modifications can be made while utilizing the present invention, meanwhile remaining within the spirit and scope of the present invention, as defined by the appended claims. | A discharge valve of a hermetic compressor includes a valve plate disposed on a cylinder head that draws in and discharges refrigerant according to reciprocal movement of a piston, and the discharge valve having a discharge hole formed therein through which refrigerant is discharged, a disc valve disposed adjacent the discharge hole of the valve plate, the disc valve being raised or lowered by the reciprocal movement of the piston and disc valve weight, and a stopper disposed above the disc valve, for guiding the raising and lowering of the disc valve and also for limiting the height to which the disc valve may be raised. The compressor is not subject to overload or over pressurization that may otherwise result from an elastic closing force operating in the valve, and as a result, compression efficiency is increased, while noise is decreased. | 5 |
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